Skip to content

Comments

dummy change#2

Closed
shashim-quic wants to merge 1 commit intoqualcomm-linux:tech/bsp/pinctrlfrom
shashim-quic:for-pinctrl
Closed

dummy change#2
shashim-quic wants to merge 1 commit intoqualcomm-linux:tech/bsp/pinctrlfrom
shashim-quic:for-pinctrl

Conversation

@shashim-quic
Copy link
Collaborator

This is a dummy PR

Signed-off-by: Shiraz Hashim <quic_shashim@quicinc.com>
@shashim-quic shashim-quic deleted the for-pinctrl branch April 22, 2025 14:43
shashim-quic pushed a commit that referenced this pull request Apr 24, 2025
The ieee80211 skb control block key (set when skb was queued) could have
been removed before ieee80211_tx_dequeue() call. ieee80211_tx_dequeue()
already called ieee80211_tx_h_select_key() to get the current key, but
the latter do not update the key in skb control block in case it is
NULL. Because some drivers actually use this key in their TX callbacks
(e.g. ath1{1,2}k_mac_op_tx()) this could lead to the use after free
below:

  BUG: KASAN: slab-use-after-free in ath11k_mac_op_tx+0x590/0x61c
  Read of size 4 at addr ffffff803083c248 by task kworker/u16:4/1440

  CPU: 3 UID: 0 PID: 1440 Comm: kworker/u16:4 Not tainted 6.13.0-ge128f627f404 #2
  Hardware name: HW (DT)
  Workqueue: bat_events batadv_send_outstanding_bcast_packet
  Call trace:
   show_stack+0x14/0x1c (C)
   dump_stack_lvl+0x58/0x74
   print_report+0x164/0x4c0
   kasan_report+0xac/0xe8
   __asan_report_load4_noabort+0x1c/0x24
   ath11k_mac_op_tx+0x590/0x61c
   ieee80211_handle_wake_tx_queue+0x12c/0x1c8
   ieee80211_queue_skb+0xdcc/0x1b4c
   ieee80211_tx+0x1ec/0x2bc
   ieee80211_xmit+0x224/0x324
   __ieee80211_subif_start_xmit+0x85c/0xcf8
   ieee80211_subif_start_xmit+0xc0/0xec4
   dev_hard_start_xmit+0xf4/0x28c
   __dev_queue_xmit+0x6ac/0x318c
   batadv_send_skb_packet+0x38c/0x4b0
   batadv_send_outstanding_bcast_packet+0x110/0x328
   process_one_work+0x578/0xc10
   worker_thread+0x4bc/0xc7c
   kthread+0x2f8/0x380
   ret_from_fork+0x10/0x20

  Allocated by task 1906:
   kasan_save_stack+0x28/0x4c
   kasan_save_track+0x1c/0x40
   kasan_save_alloc_info+0x3c/0x4c
   __kasan_kmalloc+0xac/0xb0
   __kmalloc_noprof+0x1b4/0x380
   ieee80211_key_alloc+0x3c/0xb64
   ieee80211_add_key+0x1b4/0x71c
   nl80211_new_key+0x2b4/0x5d8
   genl_family_rcv_msg_doit+0x198/0x240
  <...>

  Freed by task 1494:
   kasan_save_stack+0x28/0x4c
   kasan_save_track+0x1c/0x40
   kasan_save_free_info+0x48/0x94
   __kasan_slab_free+0x48/0x60
   kfree+0xc8/0x31c
   kfree_sensitive+0x70/0x80
   ieee80211_key_free_common+0x10c/0x174
   ieee80211_free_keys+0x188/0x46c
   ieee80211_stop_mesh+0x70/0x2cc
   ieee80211_leave_mesh+0x1c/0x60
   cfg80211_leave_mesh+0xe0/0x280
   cfg80211_leave+0x1e0/0x244
  <...>

Reset SKB control block key before calling ieee80211_tx_h_select_key()
to avoid that.

Fixes: bb42f2d ("mac80211: Move reorder-sensitive TX handlers to after TXQ dequeue")
Signed-off-by: Remi Pommarel <repk@triplefau.lt>
Link: https://patch.msgid.link/06aa507b853ca385ceded81c18b0a6dd0f081bc8.1742833382.git.repk@triplefau.lt
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
shashim-quic pushed a commit that referenced this pull request Apr 24, 2025
SMC consists of two sockets: smc_sock and kernel TCP socket.

Currently, there are two ways of creating the sockets, and syzbot reported
a lockdep splat [0] for the newer way introduced by commit d25a92c
("net/smc: Introduce IPPROTO_SMC").

  socket(AF_SMC             , SOCK_STREAM, SMCPROTO_SMC or SMCPROTO_SMC6)
  socket(AF_INET or AF_INET6, SOCK_STREAM, IPPROTO_SMC)

When a socket is allocated, sock_lock_init() sets a lockdep lock class to
sk->sk_lock.slock based on its protocol family.  In the IPPROTO_SMC case,
AF_INET or AF_INET6 lock class is assigned to smc_sock.

The repro sets IPV6_JOIN_ANYCAST for IPv6 UDP and SMC socket and exercises
smc_switch_to_fallback() for IPPROTO_SMC.

  1. smc_switch_to_fallback() is called under lock_sock() and holds
     smc->clcsock_release_lock.

      sk_lock-AF_INET6 -> &smc->clcsock_release_lock
      (sk_lock-AF_SMC)

  2. Setting IPV6_JOIN_ANYCAST to SMC holds smc->clcsock_release_lock
     and calls setsockopt() for the kernel TCP socket, which holds RTNL
     and the kernel socket's lock_sock().

      &smc->clcsock_release_lock -> rtnl_mutex (-> k-sk_lock-AF_INET6)

  3. Setting IPV6_JOIN_ANYCAST to UDP holds RTNL and lock_sock().

      rtnl_mutex -> sk_lock-AF_INET6

Then, lockdep detects a false-positive circular locking,

  .-> sk_lock-AF_INET6 -> &smc->clcsock_release_lock -> rtnl_mutex -.
  `-----------------------------------------------------------------'

but IPPROTO_SMC should have the same locking rule as AF_SMC.

      sk_lock-AF_SMC   -> &smc->clcsock_release_lock -> rtnl_mutex -> k-sk_lock-AF_INET6

Let's set the same lock class for smc_sock.

Given AF_SMC uses the same lock class for SMCPROTO_SMC and SMCPROTO_SMC6,
we do not need to separate the class for AF_INET and AF_INET6.

[0]:
WARNING: possible circular locking dependency detected
6.14.0-rc3-syzkaller-00267-gff202c5028a1 #0 Not tainted

syz.4.1528/11571 is trying to acquire lock:
ffffffff8fef8de8 (rtnl_mutex){+.+.}-{4:4}, at: ipv6_sock_ac_close+0xd9/0x110 net/ipv6/anycast.c:220

but task is already holding lock:
ffff888027f596a8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_clcsock_release+0x75/0xe0 net/smc/smc_close.c:30

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

 -> #2 (&smc->clcsock_release_lock){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
       smc_switch_to_fallback+0x2d/0xa00 net/smc/af_smc.c:903
       smc_sendmsg+0x13d/0x520 net/smc/af_smc.c:2781
       sock_sendmsg_nosec net/socket.c:718 [inline]
       __sock_sendmsg net/socket.c:733 [inline]
       ____sys_sendmsg+0xaaf/0xc90 net/socket.c:2573
       ___sys_sendmsg+0x135/0x1e0 net/socket.c:2627
       __sys_sendmsg+0x16e/0x220 net/socket.c:2659
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

 -> #1 (sk_lock-AF_INET6){+.+.}-{0:0}:
       lock_sock_nested+0x3a/0xf0 net/core/sock.c:3645
       lock_sock include/net/sock.h:1624 [inline]
       sockopt_lock_sock net/core/sock.c:1133 [inline]
       sockopt_lock_sock+0x54/0x70 net/core/sock.c:1124
       do_ipv6_setsockopt+0x2160/0x4520 net/ipv6/ipv6_sockglue.c:567
       ipv6_setsockopt+0xcb/0x170 net/ipv6/ipv6_sockglue.c:993
       udpv6_setsockopt+0x7d/0xd0 net/ipv6/udp.c:1850
       do_sock_setsockopt+0x222/0x480 net/socket.c:2303
       __sys_setsockopt+0x1a0/0x230 net/socket.c:2328
       __do_sys_setsockopt net/socket.c:2334 [inline]
       __se_sys_setsockopt net/socket.c:2331 [inline]
       __x64_sys_setsockopt+0xbd/0x160 net/socket.c:2331
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

 -> #0 (rtnl_mutex){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain kernel/locking/lockdep.c:3906 [inline]
       __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
       lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
       ipv6_sock_ac_close+0xd9/0x110 net/ipv6/anycast.c:220
       inet6_release+0x47/0x70 net/ipv6/af_inet6.c:485
       __sock_release net/socket.c:647 [inline]
       sock_release+0x8e/0x1d0 net/socket.c:675
       smc_clcsock_release+0xb7/0xe0 net/smc/smc_close.c:34
       __smc_release+0x5c2/0x880 net/smc/af_smc.c:301
       smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344
       __sock_release+0xb0/0x270 net/socket.c:647
       sock_close+0x1c/0x30 net/socket.c:1398
       __fput+0x3ff/0xb70 fs/file_table.c:464
       task_work_run+0x14e/0x250 kernel/task_work.c:227
       resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
       exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
       exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
       __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
       syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
       do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  rtnl_mutex --> sk_lock-AF_INET6 --> &smc->clcsock_release_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&smc->clcsock_release_lock);
                               lock(sk_lock-AF_INET6);
                               lock(&smc->clcsock_release_lock);
  lock(rtnl_mutex);

 *** DEADLOCK ***

2 locks held by syz.4.1528/11571:
 #0: ffff888077e88208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
 #0: ffff888077e88208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release+0x86/0x270 net/socket.c:646
 #1: ffff888027f596a8 (&smc->clcsock_release_lock){+.+.}-{4:4}, at: smc_clcsock_release+0x75/0xe0 net/smc/smc_close.c:30

stack backtrace:
CPU: 0 UID: 0 PID: 11571 Comm: syz.4.1528 Not tainted 6.14.0-rc3-syzkaller-00267-gff202c5028a1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_circular_bug+0x490/0x760 kernel/locking/lockdep.c:2076
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain kernel/locking/lockdep.c:3906 [inline]
 __lock_acquire+0x249e/0x3c40 kernel/locking/lockdep.c:5228
 lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5851
 __mutex_lock_common kernel/locking/mutex.c:585 [inline]
 __mutex_lock+0x19b/0xb10 kernel/locking/mutex.c:730
 ipv6_sock_ac_close+0xd9/0x110 net/ipv6/anycast.c:220
 inet6_release+0x47/0x70 net/ipv6/af_inet6.c:485
 __sock_release net/socket.c:647 [inline]
 sock_release+0x8e/0x1d0 net/socket.c:675
 smc_clcsock_release+0xb7/0xe0 net/smc/smc_close.c:34
 __smc_release+0x5c2/0x880 net/smc/af_smc.c:301
 smc_release+0x1fc/0x5f0 net/smc/af_smc.c:344
 __sock_release+0xb0/0x270 net/socket.c:647
 sock_close+0x1c/0x30 net/socket.c:1398
 __fput+0x3ff/0xb70 fs/file_table.c:464
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x27b/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b4b38d169
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe4efd22d8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00000000000b14a3 RCX: 00007f8b4b38d169
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f8b4b5a7ba0 R08: 0000000000000001 R09: 000000114efd25cf
R10: 00007f8b4b200000 R11: 0000000000000246 R12: 00007f8b4b5a5fac
R13: 00007f8b4b5a5fa0 R14: ffffffffffffffff R15: 00007ffe4efd23f0
 </TASK>

Fixes: d25a92c ("net/smc: Introduce IPPROTO_SMC")
Reported-by: syzbot+be6f4b383534d88989f7@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=be6f4b383534d88989f7
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Link: https://patch.msgid.link/20250407170332.26959-1-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
shashim-quic pushed a commit that referenced this pull request Apr 24, 2025
Ido Schimmel says:

====================
fib_rules: Fix iif / oif matching on L3 master device

Patch #1 fixes a recently reported regression regarding FIB rules that
match on iif / oif being a VRF device.

Patch #2 adds test cases to the FIB rules selftest.
====================

Link: https://patch.msgid.link/20250414172022.242991-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
shashim-quic pushed a commit that referenced this pull request Apr 24, 2025
Communicating with the hypervisor using the shared GHCB page requires
clearing the C bit in the mapping of that page. When executing in the
context of the EFI boot services, the page tables are owned by the
firmware, and this manipulation is not possible.

So switch to a different API for accepting memory in SEV-SNP guests, one
which is actually supported at the point during boot where the EFI stub
may need to accept memory, but the SEV-SNP init code has not executed
yet.

For simplicity, also switch the memory acceptance carried out by the
decompressor when not booting via EFI - this only involves the
allocation for the decompressed kernel, and is generally only called
after kexec, as normal boot will jump straight into the kernel from the
EFI stub.

Fixes: 6c32117 ("x86/sev: Add SNP-specific unaccepted memory support")
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Co-developed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Cc: Dionna Amalie Glaze <dionnaglaze@google.com>
Cc: Kevin Loughlin <kevinloughlin@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-efi@vger.kernel.org
Link: https://lore.kernel.org/r/20250404082921.2767593-8-ardb+git@google.com # discussion thread #1
Link: https://lore.kernel.org/r/20250410132850.3708703-2-ardb+git@google.com # discussion thread #2
Link: https://lore.kernel.org/r/20250417202120.1002102-2-ardb+git@google.com # final submission
shashim-quic pushed a commit that referenced this pull request May 16, 2025
There is a potential deadlock if we do report zones in an IO context, detailed
in below lockdep report. When one process do a report zones and another process
freezes the block device, the report zones side cannot allocate a tag because
the freeze is already started. This can thus result in new block group creation
to hang forever, blocking the write path.

Thankfully, a new block group should be created on empty zones. So, reporting
the zones is not necessary and we can set the write pointer = 0 and load the
zone capacity from the block layer using bdev_zone_capacity() helper.

 ======================================================
 WARNING: possible circular locking dependency detected
 6.14.0-rc1 #252 Not tainted
 ------------------------------------------------------
 modprobe/1110 is trying to acquire lock:
 ffff888100ac83e0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0x38f/0xb60

 but task is already holding lock:
 ffff8881205b6f20 (&q->q_usage_counter(queue)#16){++++}-{0:0}, at: sd_remove+0x85/0x130

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #3 (&q->q_usage_counter(queue)#16){++++}-{0:0}:
        blk_queue_enter+0x3d9/0x500
        blk_mq_alloc_request+0x47d/0x8e0
        scsi_execute_cmd+0x14f/0xb80
        sd_zbc_do_report_zones+0x1c1/0x470
        sd_zbc_report_zones+0x362/0xd60
        blkdev_report_zones+0x1b1/0x2e0
        btrfs_get_dev_zones+0x215/0x7e0 [btrfs]
        btrfs_load_block_group_zone_info+0x6d2/0x2c10 [btrfs]
        btrfs_make_block_group+0x36b/0x870 [btrfs]
        btrfs_create_chunk+0x147d/0x2320 [btrfs]
        btrfs_chunk_alloc+0x2ce/0xcf0 [btrfs]
        start_transaction+0xce6/0x1620 [btrfs]
        btrfs_uuid_scan_kthread+0x4ee/0x5b0 [btrfs]
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #2 (&fs_info->dev_replace.rwsem){++++}-{4:4}:
        down_read+0x9b/0x470
        btrfs_map_block+0x2ce/0x2ce0 [btrfs]
        btrfs_submit_chunk+0x2d4/0x16c0 [btrfs]
        btrfs_submit_bbio+0x16/0x30 [btrfs]
        btree_write_cache_pages+0xb5a/0xf90 [btrfs]
        do_writepages+0x17f/0x7b0
        __writeback_single_inode+0x114/0xb00
        writeback_sb_inodes+0x52b/0xe00
        wb_writeback+0x1a7/0x800
        wb_workfn+0x12a/0xbd0
        process_one_work+0x85a/0x1460
        worker_thread+0x5e2/0xfc0
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #1 (&fs_info->zoned_meta_io_lock){+.+.}-{4:4}:
        __mutex_lock+0x1aa/0x1360
        btree_write_cache_pages+0x252/0xf90 [btrfs]
        do_writepages+0x17f/0x7b0
        __writeback_single_inode+0x114/0xb00
        writeback_sb_inodes+0x52b/0xe00
        wb_writeback+0x1a7/0x800
        wb_workfn+0x12a/0xbd0
        process_one_work+0x85a/0x1460
        worker_thread+0x5e2/0xfc0
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}:
        __lock_acquire+0x2f52/0x5ea0
        lock_acquire+0x1b1/0x540
        __flush_work+0x3ac/0xb60
        wb_shutdown+0x15b/0x1f0
        bdi_unregister+0x172/0x5b0
        del_gendisk+0x841/0xa20
        sd_remove+0x85/0x130
        device_release_driver_internal+0x368/0x520
        bus_remove_device+0x1f1/0x3f0
        device_del+0x3bd/0x9c0
        __scsi_remove_device+0x272/0x340
        scsi_forget_host+0xf7/0x170
        scsi_remove_host+0xd2/0x2a0
        sdebug_driver_remove+0x52/0x2f0 [scsi_debug]
        device_release_driver_internal+0x368/0x520
        bus_remove_device+0x1f1/0x3f0
        device_del+0x3bd/0x9c0
        device_unregister+0x13/0xa0
        sdebug_do_remove_host+0x1fb/0x290 [scsi_debug]
        scsi_debug_exit+0x17/0x70 [scsi_debug]
        __do_sys_delete_module.isra.0+0x321/0x520
        do_syscall_64+0x93/0x180
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   (work_completion)(&(&wb->dwork)->work) --> &fs_info->dev_replace.rwsem --> &q->q_usage_counter(queue)#16

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&q->q_usage_counter(queue)#16);
                                lock(&fs_info->dev_replace.rwsem);
                                lock(&q->q_usage_counter(queue)#16);
   lock((work_completion)(&(&wb->dwork)->work));

  *** DEADLOCK ***

 5 locks held by modprobe/1110:
  #0: ffff88811f7bc108 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520
  #1: ffff8881022ee0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x20/0x2a0
  #2: ffff88811b4c4378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520
  #3: ffff8881205b6f20 (&q->q_usage_counter(queue)#16){++++}-{0:0}, at: sd_remove+0x85/0x130
  #4: ffffffffa3284360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xda/0xb60

 stack backtrace:
 CPU: 0 UID: 0 PID: 1110 Comm: modprobe Not tainted 6.14.0-rc1 #252
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6a/0x90
  print_circular_bug.cold+0x1e0/0x274
  check_noncircular+0x306/0x3f0
  ? __pfx_check_noncircular+0x10/0x10
  ? mark_lock+0xf5/0x1650
  ? __pfx_check_irq_usage+0x10/0x10
  ? lockdep_lock+0xca/0x1c0
  ? __pfx_lockdep_lock+0x10/0x10
  __lock_acquire+0x2f52/0x5ea0
  ? __pfx___lock_acquire+0x10/0x10
  ? __pfx_mark_lock+0x10/0x10
  lock_acquire+0x1b1/0x540
  ? __flush_work+0x38f/0xb60
  ? __pfx_lock_acquire+0x10/0x10
  ? __pfx_lock_release+0x10/0x10
  ? mark_held_locks+0x94/0xe0
  ? __flush_work+0x38f/0xb60
  __flush_work+0x3ac/0xb60
  ? __flush_work+0x38f/0xb60
  ? __pfx_mark_lock+0x10/0x10
  ? __pfx___flush_work+0x10/0x10
  ? __pfx_wq_barrier_func+0x10/0x10
  ? __pfx___might_resched+0x10/0x10
  ? mark_held_locks+0x94/0xe0
  wb_shutdown+0x15b/0x1f0
  bdi_unregister+0x172/0x5b0
  ? __pfx_bdi_unregister+0x10/0x10
  ? up_write+0x1ba/0x510
  del_gendisk+0x841/0xa20
  ? __pfx_del_gendisk+0x10/0x10
  ? _raw_spin_unlock_irqrestore+0x35/0x60
  ? __pm_runtime_resume+0x79/0x110
  sd_remove+0x85/0x130
  device_release_driver_internal+0x368/0x520
  ? kobject_put+0x5d/0x4a0
  bus_remove_device+0x1f1/0x3f0
  device_del+0x3bd/0x9c0
  ? __pfx_device_del+0x10/0x10
  __scsi_remove_device+0x272/0x340
  scsi_forget_host+0xf7/0x170
  scsi_remove_host+0xd2/0x2a0
  sdebug_driver_remove+0x52/0x2f0 [scsi_debug]
  ? kernfs_remove_by_name_ns+0xc0/0xf0
  device_release_driver_internal+0x368/0x520
  ? kobject_put+0x5d/0x4a0
  bus_remove_device+0x1f1/0x3f0
  device_del+0x3bd/0x9c0
  ? __pfx_device_del+0x10/0x10
  ? __pfx___mutex_unlock_slowpath+0x10/0x10
  device_unregister+0x13/0xa0
  sdebug_do_remove_host+0x1fb/0x290 [scsi_debug]
  scsi_debug_exit+0x17/0x70 [scsi_debug]
  __do_sys_delete_module.isra.0+0x321/0x520
  ? __pfx___do_sys_delete_module.isra.0+0x10/0x10
  ? __pfx_slab_free_after_rcu_debug+0x10/0x10
  ? kasan_save_stack+0x2c/0x50
  ? kasan_record_aux_stack+0xa3/0xb0
  ? __call_rcu_common.constprop.0+0xc4/0xfb0
  ? kmem_cache_free+0x3a0/0x590
  ? __x64_sys_close+0x78/0xd0
  do_syscall_64+0x93/0x180
  ? lock_is_held_type+0xd5/0x130
  ? __call_rcu_common.constprop.0+0x3c0/0xfb0
  ? lockdep_hardirqs_on+0x78/0x100
  ? __call_rcu_common.constprop.0+0x3c0/0xfb0
  ? __pfx___call_rcu_common.constprop.0+0x10/0x10
  ? kmem_cache_free+0x3a0/0x590
  ? lockdep_hardirqs_on_prepare+0x16d/0x400
  ? do_syscall_64+0x9f/0x180
  ? lockdep_hardirqs_on+0x78/0x100
  ? do_syscall_64+0x9f/0x180
  ? __pfx___x64_sys_openat+0x10/0x10
  ? lockdep_hardirqs_on_prepare+0x16d/0x400
  ? do_syscall_64+0x9f/0x180
  ? lockdep_hardirqs_on+0x78/0x100
  ? do_syscall_64+0x9f/0x180
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7f436712b68b
 RSP: 002b:00007ffe9f1a8658 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
 RAX: ffffffffffffffda RBX: 00005559b367fd80 RCX: 00007f436712b68b
 RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00005559b367fde8
 RBP: 00007ffe9f1a8680 R08: 1999999999999999 R09: 0000000000000000
 R10: 00007f43671a5fe0 R11: 0000000000000206 R12: 0000000000000000
 R13: 00007ffe9f1a86b0 R14: 0000000000000000 R15: 0000000000000000
  </TASK>

Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
CC: <stable@vger.kernel.org> # 6.13+
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
shashim-quic pushed a commit that referenced this pull request May 16, 2025
[BUG]
There is a bug report that a syzbot reproducer can lead to the following
busy inode at unmount time:

  BTRFS info (device loop1): last unmount of filesystem 1680000e-3c1e-4c46-84b6-56bd3909af50
  VFS: Busy inodes after unmount of loop1 (btrfs)
  ------------[ cut here ]------------
  kernel BUG at fs/super.c:650!
  Oops: invalid opcode: 0000 [#1] SMP KASAN NOPTI
  CPU: 0 UID: 0 PID: 48168 Comm: syz-executor Not tainted 6.15.0-rc2-00471-g119009db2674 #2 PREEMPT(full)
  Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
  RIP: 0010:generic_shutdown_super+0x2e9/0x390 fs/super.c:650
  Call Trace:
   <TASK>
   kill_anon_super+0x3a/0x60 fs/super.c:1237
   btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2099
   deactivate_locked_super+0xbe/0x1a0 fs/super.c:473
   deactivate_super fs/super.c:506 [inline]
   deactivate_super+0xe2/0x100 fs/super.c:502
   cleanup_mnt+0x21f/0x440 fs/namespace.c:1435
   task_work_run+0x14d/0x240 kernel/task_work.c:227
   resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
   exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
   exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
   __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
   syscall_exit_to_user_mode+0x269/0x290 kernel/entry/common.c:218
   do_syscall_64+0xd4/0x250 arch/x86/entry/syscall_64.c:100
   entry_SYSCALL_64_after_hwframe+0x77/0x7f
   </TASK>

[CAUSE]
When btrfs_alloc_path() failed, btrfs_iget() directly returned without
releasing the inode already allocated by btrfs_iget_locked().

This results the above busy inode and trigger the kernel BUG.

[FIX]
Fix it by calling iget_failed() if btrfs_alloc_path() failed.

If we hit error inside btrfs_read_locked_inode(), it will properly call
iget_failed(), so nothing to worry about.

Although the iget_failed() cleanup inside btrfs_read_locked_inode() is a
break of the normal error handling scheme, let's fix the obvious bug
and backport first, then rework the error handling later.

Reported-by: Penglei Jiang <superman.xpt@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/20250421102425.44431-1-superman.xpt@gmail.com/
Fixes: 7c855e1 ("btrfs: remove conditional path allocation in btrfs_read_locked_inode()")
CC: stable@vger.kernel.org # 6.13+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Penglei Jiang <superman.xpt@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
shashim-quic pushed a commit that referenced this pull request May 16, 2025
…ux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.15, round #2

 - Single fix for broken usage of 'multi-MIDR' infrastructure in PI
   code, adding an open-coded erratum check for everyone's favorite pile
   of sand: Cavium ThunderX
shashim-quic pushed a commit that referenced this pull request May 19, 2025
…unload

Kernel panic occurs when a devmem TCP socket is closed after NIC module
is unloaded.

This is Devmem TCP unregistration scenarios. number is an order.
(a)netlink socket close    (b)pp destroy    (c)uninstall    result
1                          2                3               OK
1                          3                2               (d)Impossible
2                          1                3               OK
3                          1                2               (e)Kernel panic
2                          3                1               (d)Impossible
3                          2                1               (d)Impossible

(a) netdev_nl_sock_priv_destroy() is called when devmem TCP socket is
    closed.
(b) page_pool_destroy() is called when the interface is down.
(c) mp_ops->uninstall() is called when an interface is unregistered.
(d) There is no scenario in mp_ops->uninstall() is called before
    page_pool_destroy().
    Because unregister_netdevice_many_notify() closes interfaces first
    and then calls mp_ops->uninstall().
(e) netdev_nl_sock_priv_destroy() accesses struct net_device to acquire
    netdev_lock().
    But if the interface module has already been removed, net_device
    pointer is invalid, so it causes kernel panic.

In summary, there are only 3 possible scenarios.
 A. sk close -> pp destroy -> uninstall.
 B. pp destroy -> sk close -> uninstall.
 C. pp destroy -> uninstall -> sk close.

Case C is a kernel panic scenario.

In order to fix this problem, It makes mp_dmabuf_devmem_uninstall() set
binding->dev to NULL.
It indicates an bound net_device was unregistered.

It makes netdev_nl_sock_priv_destroy() do not acquire netdev_lock()
if binding->dev is NULL.

A new binding->lock is added to protect a dev of a binding.
So, lock ordering is like below.
 priv->lock
 netdev_lock(dev)
 binding->lock

Tests:
Scenario A:
    ./ncdevmem -s 192.168.1.4 -c 192.168.1.2 -f $interface -l -p 8000 \
        -v 7 -t 1 -q 1 &
    pid=$!
    sleep 10
    kill $pid
    ip link set $interface down
    modprobe -rv $module

Scenario B:
    ./ncdevmem -s 192.168.1.4 -c 192.168.1.2 -f $interface -l -p 8000 \
        -v 7 -t 1 -q 1 &
    pid=$!
    sleep 10
    ip link set $interface down
    kill $pid
    modprobe -rv $module

Scenario C:
    ./ncdevmem -s 192.168.1.4 -c 192.168.1.2 -f $interface -l -p 8000 \
        -v 7 -t 1 -q 1 &
    pid=$!
    sleep 10
    modprobe -rv $module
    sleep 5
    kill $pid

Splat looks like:
Oops: general protection fault, probably for non-canonical address 0xdffffc001fffa9f7: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
KASAN: probably user-memory-access in range [0x00000000fffd4fb8-0x00000000fffd4fbf]
CPU: 0 UID: 0 PID: 2041 Comm: ncdevmem Tainted: G    B   W           6.15.0-rc1+ #2 PREEMPT(undef)  0947ec89efa0fd68838b78e36aa1617e97ff5d7f
Tainted: [B]=BAD_PAGE, [W]=WARN
RIP: 0010:__mutex_lock (./include/linux/sched.h:2244 kernel/locking/mutex.c:400 kernel/locking/mutex.c:443 kernel/locking/mutex.c:605 kernel/locking/mutex.c:746)
Code: ea 03 80 3c 02 00 0f 85 4f 13 00 00 49 8b 1e 48 83 e3 f8 74 6a 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 34 48 89 fa 48 c1 ea 03 <0f> b6 f
RSP: 0018:ffff88826f7ef730 EFLAGS: 00010203
RAX: dffffc0000000000 RBX: 00000000fffd4f88 RCX: ffffffffaa9bc811
RDX: 000000001fffa9f7 RSI: 0000000000000008 RDI: 00000000fffd4fbc
RBP: ffff88826f7ef8b0 R08: 0000000000000000 R09: ffffed103e6aa1a4
R10: 0000000000000007 R11: ffff88826f7ef442 R12: fffffbfff669f65e
R13: ffff88812a830040 R14: ffff8881f3550d20 R15: 00000000fffd4f88
FS:  0000000000000000(0000) GS:ffff888866c05000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563bed0cb288 CR3: 00000001a7c98000 CR4: 00000000007506f0
PKRU: 55555554
Call Trace:
<TASK>
 ...
 netdev_nl_sock_priv_destroy (net/core/netdev-genl.c:953 (discriminator 3))
 genl_release (net/netlink/genetlink.c:653 net/netlink/genetlink.c:694 net/netlink/genetlink.c:705)
 ...
 netlink_release (net/netlink/af_netlink.c:737)
 ...
 __sock_release (net/socket.c:647)
 sock_close (net/socket.c:1393)

Fixes: 1d22d30 ("net: drop rtnl_lock for queue_mgmt operations")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250514154028.1062909-1-ap420073@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
shashim-quic pushed a commit that referenced this pull request Jun 10, 2025
Add a compile-time check that `*$ptr` is of the type of `$type->$($f)*`.
Rename those placeholders for clarity.

Given the incorrect usage:

> diff --git a/rust/kernel/rbtree.rs b/rust/kernel/rbtree.rs
> index 8d978c8..6a7089149878 100644
> --- a/rust/kernel/rbtree.rs
> +++ b/rust/kernel/rbtree.rs
> @@ -329,7 +329,7 @@ fn raw_entry(&mut self, key: &K) -> RawEntry<'_, K, V> {
>          while !(*child_field_of_parent).is_null() {
>              let curr = *child_field_of_parent;
>              // SAFETY: All links fields we create are in a `Node<K, V>`.
> -            let node = unsafe { container_of!(curr, Node<K, V>, links) };
> +            let node = unsafe { container_of!(curr, Node<K, V>, key) };
>
>              // SAFETY: `node` is a non-null node so it is valid by the type invariants.
>              match key.cmp(unsafe { &(*node).key }) {

this patch produces the compilation error:

> error[E0308]: mismatched types
>    --> rust/kernel/lib.rs:220:45
>     |
> 220 |         $crate::assert_same_type(field_ptr, (&raw const (*container_ptr).$($fields)*).cast_mut());
>     |         ------------------------ ---------  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `*mut rb_node`, found `*mut K`
>     |         |                        |
>     |         |                        expected all arguments to be this `*mut bindings::rb_node` type because they need to match the type of this parameter
>     |         arguments to this function are incorrect
>     |
>    ::: rust/kernel/rbtree.rs:270:6
>     |
> 270 | impl<K, V> RBTree<K, V>
>     |      - found this type parameter
> ...
> 332 |             let node = unsafe { container_of!(curr, Node<K, V>, key) };
>     |                                 ------------------------------------ in this macro invocation
>     |
>     = note: expected raw pointer `*mut bindings::rb_node`
>                found raw pointer `*mut K`
> note: function defined here
>    --> rust/kernel/lib.rs:227:8
>     |
> 227 | pub fn assert_same_type<T>(_: T, _: T) {}
>     |        ^^^^^^^^^^^^^^^^ -  ----  ---- this parameter needs to match the `*mut bindings::rb_node` type of parameter #1
>     |                         |  |
>     |                         |  parameter #2 needs to match the `*mut bindings::rb_node` type of this parameter
>     |                         parameter #1 and parameter #2 both reference this parameter `T`
>     = note: this error originates in the macro `container_of` (in Nightly builds, run with -Z macro-backtrace for more info)

[ We decided to go with a variation of v1 [1] that became v4, since it
  seems like the obvious approach, the error messages seem good enough
  and the debug performance should be fine, given the kernel is always
  built with -O2.

  In the future, we may want to make the helper non-hidden, with
  proper documentation, for others to use.

  [1] https://lore.kernel.org/rust-for-linux/CANiq72kQWNfSV0KK6qs6oJt+aGdgY=hXg=wJcmK3zYcokY1LNw@mail.gmail.com/

    - Miguel ]

Suggested-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/all/CAH5fLgh6gmqGBhPMi2SKn7mCmMWfOSiS0WP5wBuGPYh9ZTAiww@mail.gmail.com/
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Link: https://lore.kernel.org/r/20250529-b4-container-of-type-check-v4-1-bf3a7ad73cec@gmail.com
[ Added intra-doc link. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Komal-Bajaj pushed a commit that referenced this pull request Jun 18, 2025
…/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.16, take #2

- Rework of system register accessors for system registers that are
  directly writen to memory, so that sanitisation of the in-memory
  value happens at the correct time (after the read, or before the
  write). For convenience, RMW-style accessors are also provided.

- Multiple fixes for the so-called "arch-timer-edge-cases' selftest,
  which was always broken.
Komal-Bajaj pushed a commit that referenced this pull request Jun 23, 2025
As-per the SBI specification, an SBI remote fence operation applies
to the entire address space if either:
1) start_addr and size are both 0
2) size is equal to 2^XLEN-1

>From the above, only #1 is checked by SBI SFENCE calls so fix the
size parameter check in SBI SFENCE calls to cover #2 as well.

Fixes: 13acfec ("RISC-V: KVM: Add remote HFENCE functions based on VCPU requests")
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Link: https://lore.kernel.org/r/20250605061458.196003-2-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Komal-Bajaj pushed a commit that referenced this pull request Jun 23, 2025
This patch fixes an issue seen in a large-scale deployment under heavy
incoming pkts where the aRFS flow wrongly matches a flow and reprograms the
NIC with wrong settings. That mis-steering causes RX-path latency spikes
and noisy neighbor effects when many connections collide on the same
hash (some of our production servers have 20-30K connections).

set_rps_cpu() calls ndo_rx_flow_steer() with flow_id that is calculated by
hashing the skb sized by the per rx-queue table size. This results in
multiple connections (even across different rx-queues) getting the same
hash value. The driver steer function modifies the wrong flow to use this
rx-queue, e.g.: Flow#1 is first added:
    Flow#1:  <ip1, port1, ip2, port2>, Hash 'h', q#10

Later when a new flow needs to be added:
	    Flow#2:  <ip3, port3, ip4, port4>, Hash 'h', q#20

The driver finds the hash 'h' from Flow#1 and updates it to use q#20. This
results in both flows getting un-optimized - packets for Flow#1 goes to
q#20, and then reprogrammed back to q#10 later and so on; and Flow #2
programming is never done as Flow#1 is matched first for all misses. Many
flows may wrongly share the same hash and reprogram rules of the original
flow each with their own q#.

Tested on two 144-core servers with 16K netperf sessions for 180s. Netperf
clients are pinned to cores 0-71 sequentially (so that wrong packets on q#s
72-143 can be measured). IRQs are set 1:1 for queues -> CPUs, enable XPS,
enable aRFS (global value is 144 * rps_flow_cnt).

Test notes about results from ice_rx_flow_steer():
---------------------------------------------------
1. "Skip:" counter increments here:
    if (fltr_info->q_index == rxq_idx ||
	arfs_entry->fltr_state != ICE_ARFS_ACTIVE)
	    goto out;
2. "Add:" counter increments here:
    ret = arfs_entry->fltr_info.fltr_id;
    INIT_HLIST_NODE(&arfs_entry->list_entry);
3. "Update:" counter increments here:
    /* update the queue to forward to on an already existing flow */

Runtime comparison: original code vs with the patch for different
rps_flow_cnt values.

+-------------------------------+--------------+--------------+
| rps_flow_cnt                  |      512     |    2048      |
+-------------------------------+--------------+--------------+
| Ratio of Pkts on Good:Bad q's | 214 vs 822K  | 1.1M vs 980K |
| Avoid wrong aRFS programming  | 0 vs 310K    | 0 vs 30K     |
| CPU User                      | 216 vs 183   | 216 vs 206   |
| CPU System                    | 1441 vs 1171 | 1447 vs 1320 |
| CPU Softirq                   | 1245 vs 920  | 1238 vs 961  |
| CPU Total                     | 29 vs 22.7   | 29 vs 24.9   |
| aRFS Update                   | 533K vs 59   | 521K vs 32   |
| aRFS Skip                     | 82M vs 77M   | 7.2M vs 4.5M |
+-------------------------------+--------------+--------------+

A separate TCP_STREAM and TCP_RR with 1,4,8,16,64,128,256,512 connections
showed no performance degradation.

Some points on the patch/aRFS behavior:
1. Enabling full tuple matching ensures flows are always correctly matched,
   even with smaller hash sizes.
2. 5-6% drop in CPU utilization as the packets arrive at the correct CPUs
   and fewer calls to driver for programming on misses.
3. Larger hash tables reduces mis-steering due to more unique flow hashes,
   but still has clashes. However, with larger per-device rps_flow_cnt, old
   flows take more time to expire and new aRFS flows cannot be added if h/w
   limits are reached (rps_may_expire_flow() succeeds when 10*rps_flow_cnt
   pkts have been processed by this cpu that are not part of the flow).

Fixes: 28bf267 ("ice: Implement aRFS")
Signed-off-by: Krishna Kumar <krikku@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rinitha S <sx.rinitha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Komal-Bajaj pushed a commit that referenced this pull request Jun 23, 2025
syzkaller reported a null-ptr-deref in sock_omalloc() while allocating
a CALIPSO option.  [0]

The NULL is of struct sock, which was fetched by sk_to_full_sk() in
calipso_req_setattr().

Since commit a1a5344 ("tcp: avoid two atomic ops for syncookies"),
reqsk->rsk_listener could be NULL when SYN Cookie is returned to its
client, as hinted by the leading SYN Cookie log.

Here are 3 options to fix the bug:

  1) Return 0 in calipso_req_setattr()
  2) Return an error in calipso_req_setattr()
  3) Alaways set rsk_listener

1) is no go as it bypasses LSM, but 2) effectively disables SYN Cookie
for CALIPSO.  3) is also no go as there have been many efforts to reduce
atomic ops and make TCP robust against DDoS.  See also commit 3b24d85
("tcp/dccp: do not touch listener sk_refcnt under synflood").

As of the blamed commit, SYN Cookie already did not need refcounting,
and no one has stumbled on the bug for 9 years, so no CALIPSO user will
care about SYN Cookie.

Let's return an error in calipso_req_setattr() and calipso_req_delattr()
in the SYN Cookie case.

This can be reproduced by [1] on Fedora and now connect() of nc times out.

[0]:
TCP: request_sock_TCPv6: Possible SYN flooding on port [::]:20002. Sending cookies.
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037]
CPU: 3 UID: 0 PID: 12262 Comm: syz.1.2611 Not tainted 6.14.0 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
RIP: 0010:read_pnet include/net/net_namespace.h:406 [inline]
RIP: 0010:sock_net include/net/sock.h:655 [inline]
RIP: 0010:sock_kmalloc+0x35/0x170 net/core/sock.c:2806
Code: 89 d5 41 54 55 89 f5 53 48 89 fb e8 25 e3 c6 fd e8 f0 91 e3 00 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 26 01 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8b
RSP: 0018:ffff88811af89038 EFLAGS: 00010216
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff888105266400
RDX: 0000000000000006 RSI: ffff88800c890000 RDI: 0000000000000030
RBP: 0000000000000050 R08: 0000000000000000 R09: ffff88810526640e
R10: ffffed1020a4cc81 R11: ffff88810526640f R12: 0000000000000000
R13: 0000000000000820 R14: ffff888105266400 R15: 0000000000000050
FS:  00007f0653a07640(0000) GS:ffff88811af80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f863ba096f4 CR3: 00000000163c0005 CR4: 0000000000770ef0
PKRU: 80000000
Call Trace:
 <IRQ>
 ipv6_renew_options+0x279/0x950 net/ipv6/exthdrs.c:1288
 calipso_req_setattr+0x181/0x340 net/ipv6/calipso.c:1204
 calipso_req_setattr+0x56/0x80 net/netlabel/netlabel_calipso.c:597
 netlbl_req_setattr+0x18a/0x440 net/netlabel/netlabel_kapi.c:1249
 selinux_netlbl_inet_conn_request+0x1fb/0x320 security/selinux/netlabel.c:342
 selinux_inet_conn_request+0x1eb/0x2c0 security/selinux/hooks.c:5551
 security_inet_conn_request+0x50/0xa0 security/security.c:4945
 tcp_v6_route_req+0x22c/0x550 net/ipv6/tcp_ipv6.c:825
 tcp_conn_request+0xec8/0x2b70 net/ipv4/tcp_input.c:7275
 tcp_v6_conn_request+0x1e3/0x440 net/ipv6/tcp_ipv6.c:1328
 tcp_rcv_state_process+0xafa/0x52b0 net/ipv4/tcp_input.c:6781
 tcp_v6_do_rcv+0x8a6/0x1a40 net/ipv6/tcp_ipv6.c:1667
 tcp_v6_rcv+0x505e/0x5b50 net/ipv6/tcp_ipv6.c:1904
 ip6_protocol_deliver_rcu+0x17c/0x1da0 net/ipv6/ip6_input.c:436
 ip6_input_finish+0x103/0x180 net/ipv6/ip6_input.c:480
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ip6_input+0x13c/0x6b0 net/ipv6/ip6_input.c:491
 dst_input include/net/dst.h:469 [inline]
 ip6_rcv_finish net/ipv6/ip6_input.c:79 [inline]
 ip6_rcv_finish+0xb6/0x490 net/ipv6/ip6_input.c:69
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ipv6_rcv+0xf9/0x490 net/ipv6/ip6_input.c:309
 __netif_receive_skb_one_core+0x12e/0x1f0 net/core/dev.c:5896
 __netif_receive_skb+0x1d/0x170 net/core/dev.c:6009
 process_backlog+0x41e/0x13b0 net/core/dev.c:6357
 __napi_poll+0xbd/0x710 net/core/dev.c:7191
 napi_poll net/core/dev.c:7260 [inline]
 net_rx_action+0x9de/0xde0 net/core/dev.c:7382
 handle_softirqs+0x19a/0x770 kernel/softirq.c:561
 do_softirq.part.0+0x36/0x70 kernel/softirq.c:462
 </IRQ>
 <TASK>
 do_softirq arch/x86/include/asm/preempt.h:26 [inline]
 __local_bh_enable_ip+0xf1/0x110 kernel/softirq.c:389
 local_bh_enable include/linux/bottom_half.h:33 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:919 [inline]
 __dev_queue_xmit+0xc2a/0x3c40 net/core/dev.c:4679
 dev_queue_xmit include/linux/netdevice.h:3313 [inline]
 neigh_hh_output include/net/neighbour.h:523 [inline]
 neigh_output include/net/neighbour.h:537 [inline]
 ip6_finish_output2+0xd69/0x1f80 net/ipv6/ip6_output.c:141
 __ip6_finish_output net/ipv6/ip6_output.c:215 [inline]
 ip6_finish_output+0x5dc/0xd60 net/ipv6/ip6_output.c:226
 NF_HOOK_COND include/linux/netfilter.h:303 [inline]
 ip6_output+0x24b/0x8d0 net/ipv6/ip6_output.c:247
 dst_output include/net/dst.h:459 [inline]
 NF_HOOK include/linux/netfilter.h:314 [inline]
 NF_HOOK include/linux/netfilter.h:308 [inline]
 ip6_xmit+0xbbc/0x20d0 net/ipv6/ip6_output.c:366
 inet6_csk_xmit+0x39a/0x720 net/ipv6/inet6_connection_sock.c:135
 __tcp_transmit_skb+0x1a7b/0x3b40 net/ipv4/tcp_output.c:1471
 tcp_transmit_skb net/ipv4/tcp_output.c:1489 [inline]
 tcp_send_syn_data net/ipv4/tcp_output.c:4059 [inline]
 tcp_connect+0x1c0c/0x4510 net/ipv4/tcp_output.c:4148
 tcp_v6_connect+0x156c/0x2080 net/ipv6/tcp_ipv6.c:333
 __inet_stream_connect+0x3a7/0xed0 net/ipv4/af_inet.c:677
 tcp_sendmsg_fastopen+0x3e2/0x710 net/ipv4/tcp.c:1039
 tcp_sendmsg_locked+0x1e82/0x3570 net/ipv4/tcp.c:1091
 tcp_sendmsg+0x2f/0x50 net/ipv4/tcp.c:1358
 inet6_sendmsg+0xb9/0x150 net/ipv6/af_inet6.c:659
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg+0xf4/0x2a0 net/socket.c:733
 __sys_sendto+0x29a/0x390 net/socket.c:2187
 __do_sys_sendto net/socket.c:2194 [inline]
 __se_sys_sendto net/socket.c:2190 [inline]
 __x64_sys_sendto+0xe1/0x1c0 net/socket.c:2190
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc3/0x1d0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f06553c47ed
Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0653a06fc8 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f0655605fa0 RCX: 00007f06553c47ed
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00007f065545db38 R08: 0000200000000140 R09: 000000000000001c
R10: f7384d4ea84b01bd R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0655605fac R14: 00007f0655606038 R15: 00007f06539e7000
 </TASK>
Modules linked in:

[1]:
dnf install -y selinux-policy-targeted policycoreutils netlabel_tools procps-ng nmap-ncat
mount -t selinuxfs none /sys/fs/selinux
load_policy
netlabelctl calipso add pass doi:1
netlabelctl map del default
netlabelctl map add default address:::1 protocol:calipso,1
sysctl net.ipv4.tcp_syncookies=2
nc -l ::1 80 &
nc ::1 80

Fixes: e1adea9 ("calipso: Allow request sockets to be relabelled by the lsm.")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Reported-by: John Cheung <john.cs.hey@gmail.com>
Closes: https://lore.kernel.org/netdev/CAP=Rh=MvfhrGADy+-WJiftV2_WzMH4VEhEFmeT28qY+4yxNu4w@mail.gmail.com/
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Link: https://patch.msgid.link/20250617224125.17299-1-kuni1840@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Komal-Bajaj pushed a commit that referenced this pull request Jul 1, 2025
The WARN_ON_ONCE is introduced on truncate_folio_batch_exceptionals() to
capture whether the filesystem has removed all DAX entries or not.

And the fix has been applied on the filesystem xfs and ext4 by the commit
0e2f80a ("fs/dax: ensure all pages are idle prior to filesystem
unmount").

Apply the missed fix on filesystem fuse to fix the runtime warning:

[    2.011450] ------------[ cut here ]------------
[    2.011873] WARNING: CPU: 0 PID: 145 at mm/truncate.c:89 truncate_folio_batch_exceptionals+0x272/0x2b0
[    2.012468] Modules linked in:
[    2.012718] CPU: 0 UID: 1000 PID: 145 Comm: weston Not tainted 6.16.0-rc2-WSL2-STABLE #2 PREEMPT(undef)
[    2.013292] RIP: 0010:truncate_folio_batch_exceptionals+0x272/0x2b0
[    2.013704] Code: 48 63 d0 41 29 c5 48 8d 1c d5 00 00 00 00 4e 8d 6c 2a 01 49 c1 e5 03 eb 09 48 83 c3 08 49 39 dd 74 83 41 f6 44 1c 08 01 74 ef <0f> 0b 49 8b 34 1e 48 89 ef e8 10 a2 17 00 eb df 48 8b 7d 00 e8 35
[    2.014845] RSP: 0018:ffffa47ec33f3b10 EFLAGS: 00010202
[    2.015279] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[    2.015884] RDX: 0000000000000000 RSI: ffffa47ec33f3ca0 RDI: ffff98aa44f3fa80
[    2.016377] RBP: ffff98aa44f3fbf0 R08: ffffa47ec33f3ba8 R09: 0000000000000000
[    2.016942] R10: 0000000000000001 R11: 0000000000000000 R12: ffffa47ec33f3ca0
[    2.017437] R13: 0000000000000008 R14: ffffa47ec33f3ba8 R15: 0000000000000000
[    2.017972] FS:  000079ce006afa40(0000) GS:ffff98aade441000(0000) knlGS:0000000000000000
[    2.018510] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    2.018987] CR2: 000079ce03e74000 CR3: 000000010784f006 CR4: 0000000000372eb0
[    2.019518] Call Trace:
[    2.019729]  <TASK>
[    2.019901]  truncate_inode_pages_range+0xd8/0x400
[    2.020280]  ? timerqueue_add+0x66/0xb0
[    2.020574]  ? get_nohz_timer_target+0x2a/0x140
[    2.020904]  ? timerqueue_add+0x66/0xb0
[    2.021231]  ? timerqueue_del+0x2e/0x50
[    2.021646]  ? __remove_hrtimer+0x39/0x90
[    2.022017]  ? srso_alias_untrain_ret+0x1/0x10
[    2.022497]  ? psi_group_change+0x136/0x350
[    2.023046]  ? _raw_spin_unlock+0xe/0x30
[    2.023514]  ? finish_task_switch.isra.0+0x8d/0x280
[    2.024068]  ? __schedule+0x532/0xbd0
[    2.024551]  fuse_evict_inode+0x29/0x190
[    2.025131]  evict+0x100/0x270
[    2.025641]  ? _atomic_dec_and_lock+0x39/0x50
[    2.026316]  ? __pfx_generic_delete_inode+0x10/0x10
[    2.026843]  __dentry_kill+0x71/0x180
[    2.027335]  dput+0xeb/0x1b0
[    2.027725]  __fput+0x136/0x2b0
[    2.028054]  __x64_sys_close+0x3d/0x80
[    2.028469]  do_syscall_64+0x6d/0x1b0
[    2.028832]  ? clear_bhb_loop+0x30/0x80
[    2.029182]  ? clear_bhb_loop+0x30/0x80
[    2.029533]  ? clear_bhb_loop+0x30/0x80
[    2.029902]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[    2.030423] RIP: 0033:0x79ce03d0d067
[    2.030820] Code: b8 ff ff ff ff e9 3e ff ff ff 66 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 41 c3 48 83 ec 18 89 7c 24 0c e8 c3 a7 f8 ff
[    2.032354] RSP: 002b:00007ffef0498948 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
[    2.032939] RAX: ffffffffffffffda RBX: 00007ffef0498960 RCX: 000079ce03d0d067
[    2.033612] RDX: 0000000000000003 RSI: 0000000000001000 RDI: 000000000000000d
[    2.034289] RBP: 00007ffef0498a30 R08: 000000000000000d R09: 0000000000000000
[    2.034944] R10: 00007ffef0498978 R11: 0000000000000246 R12: 0000000000000001
[    2.035610] R13: 00007ffef0498960 R14: 000079ce03e09ce0 R15: 0000000000000003
[    2.036301]  </TASK>
[    2.036532] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20250621171507.3770-1-haiyuewa@163.com
Fixes: bde708f ("fs/dax: always remove DAX page-cache entries when breaking layouts")
Signed-off-by: Haiyue Wang <haiyuewa@163.com>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Komal-Bajaj pushed a commit that referenced this pull request Jul 1, 2025
Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order
and prevent the following deadlock from happening

======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc3-build2+ #1301 Tainted: G S      W
------------------------------------------------------
cifsd/6055 is trying to acquire lock:
ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200

but task is already holding lock:
ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&ret_buf->chan_lock){+.+.}-{3:3}:
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_setup_session+0x81/0x4b0
       cifs_get_smb_ses+0x771/0x900
       cifs_mount_get_session+0x7e/0x170
       cifs_mount+0x92/0x2d0
       cifs_smb3_do_mount+0x161/0x460
       smb3_get_tree+0x55/0x90
       vfs_get_tree+0x46/0x180
       do_new_mount+0x1b0/0x2e0
       path_mount+0x6ee/0x740
       do_mount+0x98/0xe0
       __do_sys_mount+0x148/0x180
       do_syscall_64+0xa4/0x260
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #1 (&ret_buf->ses_lock){+.+.}-{3:3}:
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_match_super+0x101/0x320
       sget+0xab/0x270
       cifs_smb3_do_mount+0x1e0/0x460
       smb3_get_tree+0x55/0x90
       vfs_get_tree+0x46/0x180
       do_new_mount+0x1b0/0x2e0
       path_mount+0x6ee/0x740
       do_mount+0x98/0xe0
       __do_sys_mount+0x148/0x180
       do_syscall_64+0xa4/0x260
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #0 (&tcp_ses->srv_lock){+.+.}-{3:3}:
       check_noncircular+0x95/0xc0
       check_prev_add+0x115/0x2f0
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_signal_cifsd_for_reconnect+0x134/0x200
       __cifs_reconnect+0x8f/0x500
       cifs_handle_standard+0x112/0x280
       cifs_demultiplex_thread+0x64d/0xbc0
       kthread+0x2f7/0x310
       ret_from_fork+0x2a/0x230
       ret_from_fork_asm+0x1a/0x30

other info that might help us debug this:

Chain exists of:
  &tcp_ses->srv_lock --> &ret_buf->ses_lock --> &ret_buf->chan_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ret_buf->chan_lock);
                               lock(&ret_buf->ses_lock);
                               lock(&ret_buf->chan_lock);
  lock(&tcp_ses->srv_lock);

 *** DEADLOCK ***

3 locks held by cifsd/6055:
 #0: ffffffff857de398 (&cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200
 #1: ffff888119c64060 (&ret_buf->ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200
 #2: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

Cc: linux-cifs@vger.kernel.org
Reported-by: David Howells <dhowells@redhat.com>
Fixes: d7d7a66 ("cifs: avoid use of global locks for high contention data")
Reviewed-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
sgaud-quic pushed a commit that referenced this pull request Jul 7, 2025
The issue arises when kzalloc() is invoked while holding umem_mutex or
any other lock acquired under umem_mutex. This is problematic because
kzalloc() can trigger fs_reclaim_aqcuire(), which may, in turn, invoke
mmu_notifier_invalidate_range_start(). This function can lead to
mlx5_ib_invalidate_range(), which attempts to acquire umem_mutex again,
resulting in a deadlock.

The problematic flow:
             CPU0                      |              CPU1
---------------------------------------|------------------------------------------------
mlx5_ib_dereg_mr()                     |
 → revoke_mr()                         |
   → mutex_lock(&umem_odp->umem_mutex) |
                                       | mlx5_mkey_cache_init()
                                       |  → mutex_lock(&dev->cache.rb_lock)
                                       |  → mlx5r_cache_create_ent_locked()
                                       |    → kzalloc(GFP_KERNEL)
                                       |      → fs_reclaim()
                                       |        → mmu_notifier_invalidate_range_start()
                                       |          → mlx5_ib_invalidate_range()
                                       |            → mutex_lock(&umem_odp->umem_mutex)
   → cache_ent_find_and_store()        |
     → mutex_lock(&dev->cache.rb_lock) |

Additionally, when kzalloc() is called from within
cache_ent_find_and_store(), we encounter the same deadlock due to
re-acquisition of umem_mutex.

Solve by releasing umem_mutex in dereg_mr() after umr_revoke_mr()
and before acquiring rb_lock. This ensures that we don't hold
umem_mutex while performing memory allocations that could trigger
the reclaim path.

This change prevents the deadlock by ensuring proper lock ordering and
avoiding holding locks during memory allocation operations that could
trigger the reclaim path.

The following lockdep warning demonstrates the deadlock:

 python3/20557 is trying to acquire lock:
 ffff888387542128 (&umem_odp->umem_mutex){+.+.}-{4:4}, at:
 mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]

 but task is already holding lock:
 ffffffff82f6b840 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at:
 unmap_vmas+0x7b/0x1a0

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> #3 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}:
       fs_reclaim_acquire+0x60/0xd0
       mem_cgroup_css_alloc+0x6f/0x9b0
       cgroup_init_subsys+0xa4/0x240
       cgroup_init+0x1c8/0x510
       start_kernel+0x747/0x760
       x86_64_start_reservations+0x25/0x30
       x86_64_start_kernel+0x73/0x80
       common_startup_64+0x129/0x138

 -> #2 (fs_reclaim){+.+.}-{0:0}:
       fs_reclaim_acquire+0x91/0xd0
       __kmalloc_cache_noprof+0x4d/0x4c0
       mlx5r_cache_create_ent_locked+0x75/0x620 [mlx5_ib]
       mlx5_mkey_cache_init+0x186/0x360 [mlx5_ib]
       mlx5_ib_stage_post_ib_reg_umr_init+0x3c/0x60 [mlx5_ib]
       __mlx5_ib_add+0x4b/0x190 [mlx5_ib]
       mlx5r_probe+0xd9/0x320 [mlx5_ib]
       auxiliary_bus_probe+0x42/0x70
       really_probe+0xdb/0x360
       __driver_probe_device+0x8f/0x130
       driver_probe_device+0x1f/0xb0
       __driver_attach+0xd4/0x1f0
       bus_for_each_dev+0x79/0xd0
       bus_add_driver+0xf0/0x200
       driver_register+0x6e/0xc0
       __auxiliary_driver_register+0x6a/0xc0
       do_one_initcall+0x5e/0x390
       do_init_module+0x88/0x240
       init_module_from_file+0x85/0xc0
       idempotent_init_module+0x104/0x300
       __x64_sys_finit_module+0x68/0xc0
       do_syscall_64+0x6d/0x140
       entry_SYSCALL_64_after_hwframe+0x4b/0x53

 -> #1 (&dev->cache.rb_lock){+.+.}-{4:4}:
       __mutex_lock+0x98/0xf10
       __mlx5_ib_dereg_mr+0x6f2/0x890 [mlx5_ib]
       mlx5_ib_dereg_mr+0x21/0x110 [mlx5_ib]
       ib_dereg_mr_user+0x85/0x1f0 [ib_core]
       uverbs_free_mr+0x19/0x30 [ib_uverbs]
       destroy_hw_idr_uobject+0x21/0x80 [ib_uverbs]
       uverbs_destroy_uobject+0x60/0x3d0 [ib_uverbs]
       uobj_destroy+0x57/0xa0 [ib_uverbs]
       ib_uverbs_cmd_verbs+0x4d5/0x1210 [ib_uverbs]
       ib_uverbs_ioctl+0x129/0x230 [ib_uverbs]
       __x64_sys_ioctl+0x596/0xaa0
       do_syscall_64+0x6d/0x140
       entry_SYSCALL_64_after_hwframe+0x4b/0x53

 -> #0 (&umem_odp->umem_mutex){+.+.}-{4:4}:
       __lock_acquire+0x1826/0x2f00
       lock_acquire+0xd3/0x2e0
       __mutex_lock+0x98/0xf10
       mlx5_ib_invalidate_range+0x5b/0x550 [mlx5_ib]
       __mmu_notifier_invalidate_range_start+0x18e/0x1f0
       unmap_vmas+0x182/0x1a0
       exit_mmap+0xf3/0x4a0
       mmput+0x3a/0x100
       do_exit+0x2b9/0xa90
       do_group_exit+0x32/0xa0
       get_signal+0xc32/0xcb0
       arch_do_signal_or_restart+0x29/0x1d0
       syscall_exit_to_user_mode+0x105/0x1d0
       do_syscall_64+0x79/0x140
       entry_SYSCALL_64_after_hwframe+0x4b/0x53

 Chain exists of:
 &dev->cache.rb_lock --> mmu_notifier_invalidate_range_start -->
 &umem_odp->umem_mutex

 Possible unsafe locking scenario:

       CPU0                        CPU1
       ----                        ----
   lock(&umem_odp->umem_mutex);
                                lock(mmu_notifier_invalidate_range_start);
                                lock(&umem_odp->umem_mutex);
   lock(&dev->cache.rb_lock);

 *** DEADLOCK ***

Fixes: abb604a ("RDMA/mlx5: Fix a race for an ODP MR which leads to CQE with error")
Signed-off-by: Or Har-Toov <ohartoov@nvidia.com>
Reviewed-by: Michael Guralnik <michaelgur@nvidia.com>
Link: https://patch.msgid.link/3c8f225a8a9fade647d19b014df1172544643e4a.1750061612.git.leon@kernel.org
Signed-off-by: Leon Romanovsky <leon@kernel.org>
sgaud-quic pushed a commit that referenced this pull request Jul 7, 2025
When I run the NVME over TCP test in virtme-ng, I get the following
"suspicious RCU usage" warning in nvme_mpath_add_sysfs_link():

'''
[    5.024557][   T44] nvmet: Created nvm controller 1 for subsystem nqn.2025-06.org.nvmexpress.mptcp for NQN nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77.
[    5.027401][  T183] nvme nvme0: creating 2 I/O queues.
[    5.029017][  T183] nvme nvme0: mapped 2/0/0 default/read/poll queues.
[    5.032587][  T183] nvme nvme0: new ctrl: NQN "nqn.2025-06.org.nvmexpress.mptcp", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77
[    5.042214][   T25]
[    5.042440][   T25] =============================
[    5.042579][   T25] WARNING: suspicious RCU usage
[    5.042705][   T25] 6.16.0-rc3+ #23 Not tainted
[    5.042812][   T25] -----------------------------
[    5.042934][   T25] drivers/nvme/host/multipath.c:1203 RCU-list traversed in non-reader section!!
[    5.043111][   T25]
[    5.043111][   T25] other info that might help us debug this:
[    5.043111][   T25]
[    5.043341][   T25]
[    5.043341][   T25] rcu_scheduler_active = 2, debug_locks = 1
[    5.043502][   T25] 3 locks held by kworker/u9:0/25:
[    5.043615][   T25]  #0: ffff888008730948 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x7ed/0x1350
[    5.043830][   T25]  #1: ffffc900001afd40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0xcf3/0x1350
[    5.044084][   T25]  #2: ffff888013ee0020 (&head->srcu){.+.+}-{0:0}, at: nvme_mpath_add_sysfs_link.part.0+0xb4/0x3a0
[    5.044300][   T25]
[    5.044300][   T25] stack backtrace:
[    5.044439][   T25] CPU: 0 UID: 0 PID: 25 Comm: kworker/u9:0 Not tainted 6.16.0-rc3+ #23 PREEMPT(full)
[    5.044441][   T25] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    5.044442][   T25] Workqueue: async async_run_entry_fn
[    5.044445][   T25] Call Trace:
[    5.044446][   T25]  <TASK>
[    5.044449][   T25]  dump_stack_lvl+0x6f/0xb0
[    5.044453][   T25]  lockdep_rcu_suspicious.cold+0x4f/0xb1
[    5.044457][   T25]  nvme_mpath_add_sysfs_link.part.0+0x2fb/0x3a0
[    5.044459][   T25]  ? queue_work_on+0x90/0xf0
[    5.044461][   T25]  ? lockdep_hardirqs_on+0x78/0x110
[    5.044466][   T25]  nvme_mpath_set_live+0x1e9/0x4f0
[    5.044470][   T25]  nvme_mpath_add_disk+0x240/0x2f0
[    5.044472][   T25]  ? __pfx_nvme_mpath_add_disk+0x10/0x10
[    5.044475][   T25]  ? add_disk_fwnode+0x361/0x580
[    5.044480][   T25]  nvme_alloc_ns+0x81c/0x17c0
[    5.044483][   T25]  ? kasan_quarantine_put+0x104/0x240
[    5.044487][   T25]  ? __pfx_nvme_alloc_ns+0x10/0x10
[    5.044495][   T25]  ? __pfx_nvme_find_get_ns+0x10/0x10
[    5.044496][   T25]  ? rcu_read_lock_any_held+0x45/0xa0
[    5.044498][   T25]  ? validate_chain+0x232/0x4f0
[    5.044503][   T25]  nvme_scan_ns+0x4c8/0x810
[    5.044506][   T25]  ? __pfx_nvme_scan_ns+0x10/0x10
[    5.044508][   T25]  ? find_held_lock+0x2b/0x80
[    5.044512][   T25]  ? ktime_get+0x16d/0x220
[    5.044517][   T25]  ? kvm_clock_get_cycles+0x18/0x30
[    5.044520][   T25]  ? __pfx_nvme_scan_ns_async+0x10/0x10
[    5.044522][   T25]  async_run_entry_fn+0x97/0x560
[    5.044523][   T25]  ? rcu_is_watching+0x12/0xc0
[    5.044526][   T25]  process_one_work+0xd3c/0x1350
[    5.044532][   T25]  ? __pfx_process_one_work+0x10/0x10
[    5.044536][   T25]  ? assign_work+0x16c/0x240
[    5.044539][   T25]  worker_thread+0x4da/0xd50
[    5.044545][   T25]  ? __pfx_worker_thread+0x10/0x10
[    5.044546][   T25]  kthread+0x356/0x5c0
[    5.044548][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044549][   T25]  ? ret_from_fork+0x1b/0x2e0
[    5.044552][   T25]  ? __lock_release.isra.0+0x5d/0x180
[    5.044553][   T25]  ? ret_from_fork+0x1b/0x2e0
[    5.044555][   T25]  ? rcu_is_watching+0x12/0xc0
[    5.044557][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044559][   T25]  ret_from_fork+0x218/0x2e0
[    5.044561][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044562][   T25]  ret_from_fork_asm+0x1a/0x30
[    5.044570][   T25]  </TASK>
'''

This patch uses sleepable RCU version of helper list_for_each_entry_srcu()
instead of list_for_each_entry_rcu() to fix it.

Fixes: 4dbd2b2 ("nvme-multipath: Add visibility for round-robin io-policy")
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
sgaud-quic pushed a commit that referenced this pull request Jul 7, 2025
With VIRTCHNL2_CAP_MACFILTER enabled, the following warning is generated
on module load:

[  324.701677] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:578
[  324.701684] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1582, name: NetworkManager
[  324.701689] preempt_count: 201, expected: 0
[  324.701693] RCU nest depth: 0, expected: 0
[  324.701697] 2 locks held by NetworkManager/1582:
[  324.701702]  #0: ffffffff9f7be770 (rtnl_mutex){....}-{3:3}, at: rtnl_newlink+0x791/0x21e0
[  324.701730]  #1: ff1100216c380368 (_xmit_ETHER){....}-{2:2}, at: __dev_open+0x3f0/0x870
[  324.701749] Preemption disabled at:
[  324.701752] [<ffffffff9cd23b9d>] __dev_open+0x3dd/0x870
[  324.701765] CPU: 30 UID: 0 PID: 1582 Comm: NetworkManager Not tainted 6.15.0-rc5+ #2 PREEMPT(voluntary)
[  324.701771] Hardware name: Intel Corporation M50FCP2SBSTD/M50FCP2SBSTD, BIOS SE5C741.86B.01.01.0001.2211140926 11/14/2022
[  324.701774] Call Trace:
[  324.701777]  <TASK>
[  324.701779]  dump_stack_lvl+0x5d/0x80
[  324.701788]  ? __dev_open+0x3dd/0x870
[  324.701793]  __might_resched.cold+0x1ef/0x23d
<..>
[  324.701818]  __mutex_lock+0x113/0x1b80
<..>
[  324.701917]  idpf_ctlq_clean_sq+0xad/0x4b0 [idpf]
[  324.701935]  ? kasan_save_track+0x14/0x30
[  324.701941]  idpf_mb_clean+0x143/0x380 [idpf]
<..>
[  324.701991]  idpf_send_mb_msg+0x111/0x720 [idpf]
[  324.702009]  idpf_vc_xn_exec+0x4cc/0x990 [idpf]
[  324.702021]  ? rcu_is_watching+0x12/0xc0
[  324.702035]  idpf_add_del_mac_filters+0x3ed/0xb50 [idpf]
<..>
[  324.702122]  __hw_addr_sync_dev+0x1cf/0x300
[  324.702126]  ? find_held_lock+0x32/0x90
[  324.702134]  idpf_set_rx_mode+0x317/0x390 [idpf]
[  324.702152]  __dev_open+0x3f8/0x870
[  324.702159]  ? __pfx___dev_open+0x10/0x10
[  324.702174]  __dev_change_flags+0x443/0x650
<..>
[  324.702208]  netif_change_flags+0x80/0x160
[  324.702218]  do_setlink.isra.0+0x16a0/0x3960
<..>
[  324.702349]  rtnl_newlink+0x12fd/0x21e0

The sequence is as follows:
	rtnl_newlink()->
	__dev_change_flags()->
	__dev_open()->
	dev_set_rx_mode() - >  # disables BH and grabs "dev->addr_list_lock"
	idpf_set_rx_mode() ->  # proceed only if VIRTCHNL2_CAP_MACFILTER is ON
	__dev_uc_sync() ->
	idpf_add_mac_filter ->
	idpf_add_del_mac_filters ->
	idpf_send_mb_msg() ->
	idpf_mb_clean() ->
	idpf_ctlq_clean_sq()   # mutex_lock(cq_lock)

Fix by converting cq_lock to a spinlock. All operations under the new
lock are safe except freeing the DMA memory, which may use vunmap(). Fix
by requesting a contiguous physical memory for the DMA mapping.

Fixes: a251eee ("idpf: add SRIOV support and other ndo_ops")
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Ahmed Zaki <ahmed.zaki@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Samuel Salin <Samuel.salin@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
sgaud-quic pushed a commit that referenced this pull request Jul 14, 2025
…-flight

Reject migration of SEV{-ES} state if either the source or destination VM
is actively creating a vCPU, i.e. if kvm_vm_ioctl_create_vcpu() is in the
section between incrementing created_vcpus and online_vcpus.  The bulk of
vCPU creation runs _outside_ of kvm->lock to allow creating multiple vCPUs
in parallel, and so sev_info.es_active can get toggled from false=>true in
the destination VM after (or during) svm_vcpu_create(), resulting in an
SEV{-ES} VM effectively having a non-SEV{-ES} vCPU.

The issue manifests most visibly as a crash when trying to free a vCPU's
NULL VMSA page in an SEV-ES VM, but any number of things can go wrong.

  BUG: unable to handle page fault for address: ffffebde00000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] SMP KASAN NOPTI
  CPU: 227 UID: 0 PID: 64063 Comm: syz.5.60023 Tainted: G     U     O        6.15.0-smp-DEV #2 NONE
  Tainted: [U]=USER, [O]=OOT_MODULE
  Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.52.0-0 10/28/2024
  RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline]
  RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline]
  RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
  RIP: 0010:PageHead include/linux/page-flags.h:866 [inline]
  RIP: 0010:___free_pages+0x3e/0x120 mm/page_alloc.c:5067
  Code: <49> f7 06 40 00 00 00 75 05 45 31 ff eb 0c 66 90 4c 89 f0 4c 39 f0
  RSP: 0018:ffff8984551978d0 EFLAGS: 00010246
  RAX: 0000777f80000001 RBX: 0000000000000000 RCX: ffffffff918aeb98
  RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffebde00000000
  RBP: 0000000000000000 R08: ffffebde00000007 R09: 1ffffd7bc0000000
  R10: dffffc0000000000 R11: fffff97bc0000001 R12: dffffc0000000000
  R13: ffff8983e19751a8 R14: ffffebde00000000 R15: 1ffffd7bc0000000
  FS:  0000000000000000(0000) GS:ffff89ee661d3000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffebde00000000 CR3: 000000793ceaa000 CR4: 0000000000350ef0
  DR0: 0000000000000000 DR1: 0000000000000b5f DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   sev_free_vcpu+0x413/0x630 arch/x86/kvm/svm/sev.c:3169
   svm_vcpu_free+0x13a/0x2a0 arch/x86/kvm/svm/svm.c:1515
   kvm_arch_vcpu_destroy+0x6a/0x1d0 arch/x86/kvm/x86.c:12396
   kvm_vcpu_destroy virt/kvm/kvm_main.c:470 [inline]
   kvm_destroy_vcpus+0xd1/0x300 virt/kvm/kvm_main.c:490
   kvm_arch_destroy_vm+0x636/0x820 arch/x86/kvm/x86.c:12895
   kvm_put_kvm+0xb8e/0xfb0 virt/kvm/kvm_main.c:1310
   kvm_vm_release+0x48/0x60 virt/kvm/kvm_main.c:1369
   __fput+0x3e4/0x9e0 fs/file_table.c:465
   task_work_run+0x1a9/0x220 kernel/task_work.c:227
   exit_task_work include/linux/task_work.h:40 [inline]
   do_exit+0x7f0/0x25b0 kernel/exit.c:953
   do_group_exit+0x203/0x2d0 kernel/exit.c:1102
   get_signal+0x1357/0x1480 kernel/signal.c:3034
   arch_do_signal_or_restart+0x40/0x690 arch/x86/kernel/signal.c:337
   exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
   exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
   __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
   syscall_exit_to_user_mode+0x67/0xb0 kernel/entry/common.c:218
   do_syscall_64+0x7c/0x150 arch/x86/entry/syscall_64.c:100
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f87a898e969
   </TASK>
  Modules linked in: gq(O)
  gsmi: Log Shutdown Reason 0x03
  CR2: ffffebde00000000
  ---[ end trace 0000000000000000 ]---

Deliberately don't check for a NULL VMSA when freeing the vCPU, as crashing
the host is likely desirable due to the VMSA being consumed by hardware.
E.g. if KVM manages to allow VMRUN on the vCPU, hardware may read/write a
bogus VMSA page.  Accessing PFN 0 is "fine"-ish now that it's sequestered
away thanks to L1TF, but panicking in this scenario is preferable to
potentially running with corrupted state.

Reported-by: Alexander Potapenko <glider@google.com>
Tested-by: Alexander Potapenko <glider@google.com>
Fixes: 0b020f5 ("KVM: SEV: Add support for SEV-ES intra host migration")
Fixes: b566393 ("KVM: SEV: Add support for SEV intra host migration")
Cc: stable@vger.kernel.org
Cc: James Houghton <jthoughton@google.com>
Cc: Peter Gonda <pgonda@google.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Tested-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: James Houghton <jthoughton@google.com>
Link: https://lore.kernel.org/r/20250602224459.41505-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
sgaud-quic pushed a commit that referenced this pull request Jul 21, 2025
If the PHY driver uses another PHY internally (e.g. in case of eUSB2,
repeaters are represented as PHYs), then it would trigger the following
lockdep splat because all PHYs use a single static lockdep key and thus
lockdep can not identify whether there is a dependency or not and
reports a false positive.

Make PHY subsystem use dynamic lockdep keys, assigning each driver a
separate key. This way lockdep can correctly identify dependency graph
between mutexes.

 ============================================
 WARNING: possible recursive locking detected
 6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 Not tainted
 --------------------------------------------
 kworker/u51:0/78 is trying to acquire lock:
 ffff0008116554f0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c

 but task is already holding lock:
 ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&phy->mutex);
   lock(&phy->mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 4 locks held by kworker/u51:0/78:
  #0: ffff000800010948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x18c/0x5ec
  #1: ffff80008036bdb0 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x1b4/0x5ec
  #2: ffff0008094ac8f8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x38/0x188
  #3: ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c

 stack backtrace:
 CPU: 0 UID: 0 PID: 78 Comm: kworker/u51:0 Not tainted 6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 PREEMPT
 Hardware name: Qualcomm CRD, BIOS 6.0.240904.BOOT.MXF.2.4-00528.1-HAMOA-1 09/ 4/2024
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  show_stack+0x18/0x24 (C)
  dump_stack_lvl+0x90/0xd0
  dump_stack+0x18/0x24
  print_deadlock_bug+0x258/0x348
  __lock_acquire+0x10fc/0x1f84
  lock_acquire+0x1c8/0x338
  __mutex_lock+0xb8/0x59c
  mutex_lock_nested+0x24/0x30
  phy_init+0x4c/0x12c
  snps_eusb2_hsphy_init+0x54/0x1a0
  phy_init+0xe0/0x12c
  dwc3_core_init+0x450/0x10b4
  dwc3_core_probe+0xce4/0x15fc
  dwc3_probe+0x64/0xb0
  platform_probe+0x68/0xc4
  really_probe+0xbc/0x298
  __driver_probe_device+0x78/0x12c
  driver_probe_device+0x3c/0x160
  __device_attach_driver+0xb8/0x138
  bus_for_each_drv+0x84/0xe0
  __device_attach+0x9c/0x188
  device_initial_probe+0x14/0x20
  bus_probe_device+0xac/0xb0
  deferred_probe_work_func+0x8c/0xc8
  process_one_work+0x208/0x5ec
  worker_thread+0x1c0/0x368
  kthread+0x14c/0x20c
  ret_from_fork+0x10/0x20

Fixes: 3584f63 ("phy: qcom: phy-qcom-snps-eusb2: Add support for eUSB2 repeater")
Fixes: e246355 ("phy: amlogic: Add Amlogic AXG PCIE PHY Driver")
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Reviewed-by: Abel Vesa <abel.vesa@linaro.org>
Reported-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/lkml/ZnpoAVGJMG4Zu-Jw@hovoldconsulting.com/
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20250605-phy-subinit-v3-1-1e1e849e10cd@oss.qualcomm.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
sgaud-quic pushed a commit that referenced this pull request Jul 21, 2025
If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP
is enabled for dm-bufio. However, when bufio tries to evict buffers, there
is a chance to trigger scheduling in spin_lock_bh, the following warning
is hit:

BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
4 locks held by kworker/2:2/123:
 #0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970
 #1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970
 #2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710
 #3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 #305 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: dm_bufio_cache do_global_cleanup
Call Trace:
 <TASK>
 dump_stack_lvl+0x53/0x70
 __might_resched+0x360/0x4e0
 do_global_cleanup+0x2f5/0x710
 process_one_work+0x7db/0x1970
 worker_thread+0x518/0xea0
 kthread+0x359/0x690
 ret_from_fork+0xf3/0x1b0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

That can be reproduced by:

  veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb
  SIZE=$(blockdev --getsz /dev/vda)
  dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet"
  mount /dev/dm-0 /mnt -o ro
  echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes
  [read files in /mnt]

Cc: stable@vger.kernel.org	# v6.4+
Fixes: 450e8de ("dm bufio: improve concurrent IO performance")
Signed-off-by: Wang Shuai <wangshuai12@xiaomi.com>
Signed-off-by: Sheng Yong <shengyong1@xiaomi.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
sgaud-quic pushed a commit that referenced this pull request Jul 21, 2025
This reverts commit 7796c97.

This patch broke Dragonboard 845c (sdm845). I see:

    Unexpected kernel BRK exception at EL1
    Internal error: BRK handler: 00000000f20003e8 [#1]  SMP
    pc : qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom]
    lr : snd_soc_dai_set_channel_map+0x34/0x78
    Call trace:
     qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom] (P)
     sdm845_dai_init+0x18c/0x2e0 [snd_soc_sdm845]
     snd_soc_link_init+0x28/0x6c
     snd_soc_bind_card+0x5f4/0xb0c
     snd_soc_register_card+0x148/0x1a4
     devm_snd_soc_register_card+0x50/0xb0
     sdm845_snd_platform_probe+0x124/0x148 [snd_soc_sdm845]
     platform_probe+0x6c/0xd0
     really_probe+0xc0/0x2a4
     __driver_probe_device+0x7c/0x130
     driver_probe_device+0x40/0x118
     __device_attach_driver+0xc4/0x108
     bus_for_each_drv+0x8c/0xf0
     __device_attach+0xa4/0x198
     device_initial_probe+0x18/0x28
     bus_probe_device+0xb8/0xbc
     deferred_probe_work_func+0xac/0xfc
     process_one_work+0x244/0x658
     worker_thread+0x1b4/0x360
     kthread+0x148/0x228
     ret_from_fork+0x10/0x20
    Kernel panic - not syncing: BRK handler: Fatal exception

Dan has also reported following issues with the original patch
https://lore.kernel.org/all/33fe8fe7-719a-405a-9ed2-d9f816ce1d57@sabinyo.mountain/

Bug #1:
The zeroeth element of ctrl->pconfig[] is supposed to be unused.  We
start counting at 1.  However this code sets ctrl->pconfig[0].ch_mask = 128.

Bug #2:
There are SLIM_MAX_TX_PORTS (16) elements in tx_ch[] array but only
QCOM_SDW_MAX_PORTS + 1 (15) in the ctrl->pconfig[] array so it corrupts
memory like Yongqin Liu pointed out.

Bug 3:
Like Jie Gan pointed out, it erases all the tx information with the rx
information.

Cc: stable@vger.kernel.org # v6.15+
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Acked-by: Srinivas Kandagatla <srini@kernel.org>
Link: https://lore.kernel.org/r/20250709174949.8541-1-amit.pundir@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
sgaud-quic pushed a commit that referenced this pull request Jul 21, 2025
 into HEAD

KVM/riscv fixes for 6.16, take #2

- Disable vstimecmp before exiting to user-space
- Move HGEI[E|P] CSR access to IMSIC virtualization
shashim-quic pushed a commit that referenced this pull request Aug 11, 2025
…git/rostedt/linux-ktest

Pull ktest updates from Steven Rostedt:

 - Add new -D option that allows to override variables and options

   For example:

     ./ktest.pl -DPATCH_START:=HEAD~1 -DOUTPUT_DIR=/work/build/urgent config

   The above sets the variable "PATCH_START" to HEAD~1 and the
   OUTPUT_DIR option to "/work/build/urgent".

   This is useful because currently the only way to make a slight change
   to a config file is by modifying that config file. For one time
   changes, this can be annoying. Having a way to do a one time override
   from the command line simplifies the workflow.

   Temp variables (PATCH_START) will override every temp variable in the
   config file, whereas options will act like a normal OVERRIDE option
   and will only affect the session they define.

      -DBUILD_OUTPUT=/work/git/linux.git

   Replaces the default BUILD_OUTPUT option.

      '-DBUILD_OUTPUT[2]=/work/git/linux.git'

   Only replaces the BUILD_OUTPUT variable for test #2.

 - If an option contains itself, just drop it instead of going into an
   infinite loop and failing to parse (it doesn't crash, it detects the
   recursion after 100 iterations anyway).

   Some configs may define a variable with the same name as the option:

      ADD_CONFIG := $(ADD_CONFIG)

   But if the option doesn't exist, it the above will fail to parse. In
   these cases, just ignore evaluating the option inside the definition
   of another option if it has the same name.

 - Display the BUILD_DIR and OUTPUT_DIR options at the start of every
   test

   It is useful to know which kernel source and what destination a test
   is using when it starts, in case a mistake is made. This makes it
   easier to abort the test if the wrong source or destination is being
   used instead of waiting until the test completes.

 - Add new PATCHCHECK_SKIP option

   When testing a series of commits that also includes changes to the
   Linux tools directory, it is useless to test the changes in tools as
   they may not affect the kernel itself. Doing tests on the kernel for
   changes that do not affect the kernel is a waste of time.

   Add a PATCHCHECK_SKIP that takes a series of shas that will be
   skipped while doing the individual commit tests.

* tag 'ktest-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-ktest:
  ktest.pl: Add new PATCHCHECK_SKIP option to skip testing individual commits
  ktest.pl: Always display BUILD_DIR and OUTPUT_DIR at the start of tests
  ktest.pl: Prevent recursion of default variable options
  ktest.pl: Have -D option work without a space
  ktest.pl: Allow command option -D to override temp variables
  ktest.pl: Add -D option to override options
shashim-quic pushed a commit that referenced this pull request Aug 22, 2025
With KASAN enabled, it is possible to get a slab out of bounds
during mount to ksmbd due to missing check in parse_server_interfaces()
(see below):

 BUG: KASAN: slab-out-of-bounds in
 parse_server_interfaces+0x14ee/0x1880 [cifs]
 Read of size 4 at addr ffff8881433dba98 by task mount/9827

 CPU: 5 UID: 0 PID: 9827 Comm: mount Tainted: G
 OE       6.16.0-rc2-kasan #2 PREEMPT(voluntary)
 Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
 Hardware name: Dell Inc. Precision Tower 3620/0MWYPT,
 BIOS 2.13.1 06/14/2019
 Call Trace:
  <TASK>
 dump_stack_lvl+0x9f/0xf0
 print_report+0xd1/0x670
 __virt_addr_valid+0x22c/0x430
 ? parse_server_interfaces+0x14ee/0x1880 [cifs]
 ? kasan_complete_mode_report_info+0x2a/0x1f0
 ? parse_server_interfaces+0x14ee/0x1880 [cifs]
   kasan_report+0xd6/0x110
   parse_server_interfaces+0x14ee/0x1880 [cifs]
   __asan_report_load_n_noabort+0x13/0x20
   parse_server_interfaces+0x14ee/0x1880 [cifs]
 ? __pfx_parse_server_interfaces+0x10/0x10 [cifs]
 ? trace_hardirqs_on+0x51/0x60
 SMB3_request_interfaces+0x1ad/0x3f0 [cifs]
 ? __pfx_SMB3_request_interfaces+0x10/0x10 [cifs]
 ? SMB2_tcon+0x23c/0x15d0 [cifs]
 smb3_qfs_tcon+0x173/0x2b0 [cifs]
 ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs]
 ? cifs_get_tcon+0x105d/0x2120 [cifs]
 ? do_raw_spin_unlock+0x5d/0x200
 ? cifs_get_tcon+0x105d/0x2120 [cifs]
 ? __pfx_smb3_qfs_tcon+0x10/0x10 [cifs]
 cifs_mount_get_tcon+0x369/0xb90 [cifs]
 ? dfs_cache_find+0xe7/0x150 [cifs]
 dfs_mount_share+0x985/0x2970 [cifs]
 ? check_path.constprop.0+0x28/0x50
 ? save_trace+0x54/0x370
 ? __pfx_dfs_mount_share+0x10/0x10 [cifs]
 ? __lock_acquire+0xb82/0x2ba0
 ? __kasan_check_write+0x18/0x20
 cifs_mount+0xbc/0x9e0 [cifs]
 ? __pfx_cifs_mount+0x10/0x10 [cifs]
 ? do_raw_spin_unlock+0x5d/0x200
 ? cifs_setup_cifs_sb+0x29d/0x810 [cifs]
 cifs_smb3_do_mount+0x263/0x1990 [cifs]

Reported-by: Namjae Jeon <linkinjeon@kernel.org>
Tested-by: Namjae Jeon <linkinjeon@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Steve French <stfrench@microsoft.com>
shashim-quic pushed a commit that referenced this pull request Aug 25, 2025
The commit under the Fixes tag added a netdev_assert_locked() in
bnxt_free_ntp_fltrs().  The lock should be held during normal run-time
but the assert will be triggered (see below) during bnxt_remove_one()
which should not need the lock.  The netdev is already unregistered by
then.  Fix it by calling netdev_assert_locked_or_invisible() which will
not assert if the netdev is unregistered.

WARNING: CPU: 5 PID: 2241 at ./include/net/netdev_lock.h:17 bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en]
Modules linked in: rpcrdma rdma_cm iw_cm ib_cm configfs ib_core bnxt_en(-) bridge stp llc x86_pkg_temp_thermal xfs tg3 [last unloaded: bnxt_re]
CPU: 5 UID: 0 PID: 2241 Comm: rmmod Tainted: G S      W           6.16.0 #2 PREEMPT(voluntary)
Tainted: [S]=CPU_OUT_OF_SPEC, [W]=WARN
Hardware name: Dell Inc. PowerEdge R730/072T6D, BIOS 2.4.3 01/17/2017
RIP: 0010:bnxt_free_ntp_fltrs+0xf8/0x100 [bnxt_en]
Code: 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc 48 8b 47 60 be ff ff ff ff 48 8d b8 28 0c 00 00 e8 d0 cf 41 c3 85 c0 0f 85 2e ff ff ff <0f> 0b e9 27 ff ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffa92082387da0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff9e5b593d8000 RCX: 0000000000000001
RDX: 0000000000000001 RSI: ffffffff83dc9a70 RDI: ffffffff83e1a1cf
RBP: ffff9e5b593d8c80 R08: 0000000000000000 R09: ffffffff8373a2b3
R10: 000000008100009f R11: 0000000000000001 R12: 0000000000000001
R13: ffffffffc01c4478 R14: dead000000000122 R15: dead000000000100
FS:  00007f3a8a52c740(0000) GS:ffff9e631ad1c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055bb289419c8 CR3: 000000011274e001 CR4: 00000000003706f0
Call Trace:
 <TASK>
 bnxt_remove_one+0x57/0x180 [bnxt_en]
 pci_device_remove+0x39/0xc0
 device_release_driver_internal+0xa5/0x130
 driver_detach+0x42/0x90
 bus_remove_driver+0x61/0xc0
 pci_unregister_driver+0x38/0x90
 bnxt_exit+0xc/0x7d0 [bnxt_en]

Fixes: 004b500 ("eth: bnxt: remove most dependencies on RTNL")
Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20250816183850.4125033-1-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
shashim-quic pushed a commit that referenced this pull request Aug 25, 2025
Commit 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service
routine to a threaded IRQ handler") introduced an IRQ lock inversion
issue. Fix this lock inversion by changing the spin_lock_irq() calls into
spin_lock_irqsave() calls in code that can be called either from
interrupt context or from thread context. This patch fixes the following
lockdep complaint:

WARNING: possible irq lock inversion dependency detected
6.12.30-android16-5-maybe-dirty-4k #1 Tainted: G        W  OE
--------------------------------------------------------
kworker/u28:0/12 just changed the state of lock:
ffffff881e29dd60 (&hba->clk_gating.lock){-...}-{2:2}, at: ufshcd_release_scsi_cmd+0x60/0x110
but this lock took another, HARDIRQ-unsafe lock in the past:
 (shost->host_lock){+.+.}-{2:2}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(shost->host_lock);
                               local_irq_disable();
                               lock(&hba->clk_gating.lock);
                               lock(shost->host_lock);
  <Interrupt>
    lock(&hba->clk_gating.lock);

 *** DEADLOCK ***

4 locks held by kworker/u28:0/12:
 #0: ffffff8800ac6158 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c
 #1: ffffffc085c93d70 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c
 #2: ffffff881e29c0e0 (&shost->scan_mutex){+.+.}-{3:3}, at: __scsi_add_device+0x74/0x120
 #3: ffffff881960ea00 (&hwq->cq_lock){-...}-{2:2}, at: ufshcd_mcq_poll_cqe_lock+0x28/0x104

the shortest dependencies between 2nd lock and 1st lock:
 -> (shost->host_lock){+.+.}-{2:2} {
    HARDIRQ-ON-W at:
                      lock_acquire+0x134/0x2b4
                      _raw_spin_lock+0x48/0x64
                      ufshcd_sl_intr+0x4c/0xa08
                      ufshcd_threaded_intr+0x70/0x12c
                      irq_thread_fn+0x48/0xa8
                      irq_thread+0x130/0x1ec
                      kthread+0x110/0x134
                      ret_from_fork+0x10/0x20
    SOFTIRQ-ON-W at:
                      lock_acquire+0x134/0x2b4
                      _raw_spin_lock+0x48/0x64
                      ufshcd_sl_intr+0x4c/0xa08
                      ufshcd_threaded_intr+0x70/0x12c
                      irq_thread_fn+0x48/0xa8
                      irq_thread+0x130/0x1ec
                      kthread+0x110/0x134
                      ret_from_fork+0x10/0x20
    INITIAL USE at:
                     lock_acquire+0x134/0x2b4
                     _raw_spin_lock+0x48/0x64
                     ufshcd_sl_intr+0x4c/0xa08
                     ufshcd_threaded_intr+0x70/0x12c
                     irq_thread_fn+0x48/0xa8
                     irq_thread+0x130/0x1ec
                     kthread+0x110/0x134
                     ret_from_fork+0x10/0x20
  }
  ... key      at: [<ffffffc085ba1a98>] scsi_host_alloc.__key+0x0/0x10
  ... acquired at:
   _raw_spin_lock_irqsave+0x5c/0x80
   __ufshcd_release+0x78/0x118
   ufshcd_send_uic_cmd+0xe4/0x118
   ufshcd_dme_set_attr+0x88/0x1c8
   ufs_google_phy_initialization+0x68/0x418 [ufs]
   ufs_google_link_startup_notify+0x78/0x27c [ufs]
   ufshcd_link_startup+0x84/0x720
   ufshcd_init+0xf3c/0x1330
   ufshcd_pltfrm_init+0x728/0x7d8
   ufs_google_probe+0x30/0x84 [ufs]
   platform_probe+0xa0/0xe0
   really_probe+0x114/0x454
   __driver_probe_device+0xa4/0x160
   driver_probe_device+0x44/0x23c
   __driver_attach_async_helper+0x60/0xd4
   async_run_entry_fn+0x4c/0x17c
   process_one_work+0x26c/0x65c
   worker_thread+0x33c/0x498
   kthread+0x110/0x134
   ret_from_fork+0x10/0x20

-> (&hba->clk_gating.lock){-...}-{2:2} {
   IN-HARDIRQ-W at:
                    lock_acquire+0x134/0x2b4
                    _raw_spin_lock_irqsave+0x5c/0x80
                    ufshcd_release_scsi_cmd+0x60/0x110
                    ufshcd_compl_one_cqe+0x2c0/0x3f4
                    ufshcd_mcq_poll_cqe_lock+0xb0/0x104
                    ufs_google_mcq_intr+0x80/0xa0 [ufs]
                    __handle_irq_event_percpu+0x104/0x32c
                    handle_irq_event+0x40/0x9c
                    handle_fasteoi_irq+0x170/0x2e8
                    generic_handle_domain_irq+0x58/0x80
                    gic_handle_irq+0x48/0x104
                    call_on_irq_stack+0x3c/0x50
                    do_interrupt_handler+0x7c/0xd8
                    el1_interrupt+0x34/0x58
                    el1h_64_irq_handler+0x18/0x24
                    el1h_64_irq+0x68/0x6c
                    _raw_spin_unlock_irqrestore+0x3c/0x6c
                    debug_object_assert_init+0x16c/0x21c
                    __mod_timer+0x4c/0x48c
                    schedule_timeout+0xd4/0x16c
                    io_schedule_timeout+0x48/0x70
                    do_wait_for_common+0x100/0x194
                    wait_for_completion_io_timeout+0x48/0x6c
                    blk_execute_rq+0x124/0x17c
                    scsi_execute_cmd+0x18c/0x3f8
                    scsi_probe_and_add_lun+0x204/0xd74
                    __scsi_add_device+0xbc/0x120
                    ufshcd_async_scan+0x80/0x3c0
                    async_run_entry_fn+0x4c/0x17c
                    process_one_work+0x26c/0x65c
                    worker_thread+0x33c/0x498
                    kthread+0x110/0x134
                    ret_from_fork+0x10/0x20
   INITIAL USE at:
                   lock_acquire+0x134/0x2b4
                   _raw_spin_lock_irqsave+0x5c/0x80
                   ufshcd_hold+0x34/0x14c
                   ufshcd_send_uic_cmd+0x28/0x118
                   ufshcd_dme_set_attr+0x88/0x1c8
                   ufs_google_phy_initialization+0x68/0x418 [ufs]
                   ufs_google_link_startup_notify+0x78/0x27c [ufs]
                   ufshcd_link_startup+0x84/0x720
                   ufshcd_init+0xf3c/0x1330
                   ufshcd_pltfrm_init+0x728/0x7d8
                   ufs_google_probe+0x30/0x84 [ufs]
                   platform_probe+0xa0/0xe0
                   really_probe+0x114/0x454
                   __driver_probe_device+0xa4/0x160
                   driver_probe_device+0x44/0x23c
                   __driver_attach_async_helper+0x60/0xd4
                   async_run_entry_fn+0x4c/0x17c
                   process_one_work+0x26c/0x65c
                   worker_thread+0x33c/0x498
                   kthread+0x110/0x134
                   ret_from_fork+0x10/0x20
 }
 ... key      at: [<ffffffc085ba6fe8>] ufshcd_init.__key+0x0/0x10
 ... acquired at:
   mark_lock+0x1c4/0x224
   __lock_acquire+0x438/0x2e1c
   lock_acquire+0x134/0x2b4
   _raw_spin_lock_irqsave+0x5c/0x80
   ufshcd_release_scsi_cmd+0x60/0x110
   ufshcd_compl_one_cqe+0x2c0/0x3f4
   ufshcd_mcq_poll_cqe_lock+0xb0/0x104
   ufs_google_mcq_intr+0x80/0xa0 [ufs]
   __handle_irq_event_percpu+0x104/0x32c
   handle_irq_event+0x40/0x9c
   handle_fasteoi_irq+0x170/0x2e8
   generic_handle_domain_irq+0x58/0x80
   gic_handle_irq+0x48/0x104
   call_on_irq_stack+0x3c/0x50
   do_interrupt_handler+0x7c/0xd8
   el1_interrupt+0x34/0x58
   el1h_64_irq_handler+0x18/0x24
   el1h_64_irq+0x68/0x6c
   _raw_spin_unlock_irqrestore+0x3c/0x6c
   debug_object_assert_init+0x16c/0x21c
   __mod_timer+0x4c/0x48c
   schedule_timeout+0xd4/0x16c
   io_schedule_timeout+0x48/0x70
   do_wait_for_common+0x100/0x194
   wait_for_completion_io_timeout+0x48/0x6c
   blk_execute_rq+0x124/0x17c
   scsi_execute_cmd+0x18c/0x3f8
   scsi_probe_and_add_lun+0x204/0xd74
   __scsi_add_device+0xbc/0x120
   ufshcd_async_scan+0x80/0x3c0
   async_run_entry_fn+0x4c/0x17c
   process_one_work+0x26c/0x65c
   worker_thread+0x33c/0x498
   kthread+0x110/0x134
   ret_from_fork+0x10/0x20

stack backtrace:
CPU: 6 UID: 0 PID: 12 Comm: kworker/u28:0 Tainted: G        W  OE      6.12.30-android16-5-maybe-dirty-4k #1 ccd4020fe444bdf629efc3b86df6be920b8df7d0
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Spacecraft board based on MALIBU (DT)
Workqueue: async async_run_entry_fn
Call trace:
 dump_backtrace+0xfc/0x17c
 show_stack+0x18/0x28
 dump_stack_lvl+0x40/0xa0
 dump_stack+0x18/0x24
 print_irq_inversion_bug+0x2fc/0x304
 mark_lock_irq+0x388/0x4fc
 mark_lock+0x1c4/0x224
 __lock_acquire+0x438/0x2e1c
 lock_acquire+0x134/0x2b4
 _raw_spin_lock_irqsave+0x5c/0x80
 ufshcd_release_scsi_cmd+0x60/0x110
 ufshcd_compl_one_cqe+0x2c0/0x3f4
 ufshcd_mcq_poll_cqe_lock+0xb0/0x104
 ufs_google_mcq_intr+0x80/0xa0 [ufs dd6f385554e109da094ab91d5f7be18625a2222a]
 __handle_irq_event_percpu+0x104/0x32c
 handle_irq_event+0x40/0x9c
 handle_fasteoi_irq+0x170/0x2e8
 generic_handle_domain_irq+0x58/0x80
 gic_handle_irq+0x48/0x104
 call_on_irq_stack+0x3c/0x50
 do_interrupt_handler+0x7c/0xd8
 el1_interrupt+0x34/0x58
 el1h_64_irq_handler+0x18/0x24
 el1h_64_irq+0x68/0x6c
 _raw_spin_unlock_irqrestore+0x3c/0x6c
 debug_object_assert_init+0x16c/0x21c
 __mod_timer+0x4c/0x48c
 schedule_timeout+0xd4/0x16c
 io_schedule_timeout+0x48/0x70
 do_wait_for_common+0x100/0x194
 wait_for_completion_io_timeout+0x48/0x6c
 blk_execute_rq+0x124/0x17c
 scsi_execute_cmd+0x18c/0x3f8
 scsi_probe_and_add_lun+0x204/0xd74
 __scsi_add_device+0xbc/0x120
 ufshcd_async_scan+0x80/0x3c0
 async_run_entry_fn+0x4c/0x17c
 process_one_work+0x26c/0x65c
 worker_thread+0x33c/0x498
 kthread+0x110/0x134
 ret_from_fork+0x10/0x20

Cc: Neil Armstrong <neil.armstrong@linaro.org>
Cc: André Draszik <andre.draszik@linaro.org>
Reviewed-by: Peter Wang <peter.wang@mediatek.com>
Fixes: 3c7ac40 ("scsi: ufs: core: Delegate the interrupt service routine to a threaded IRQ handler")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20250815155842.472867-2-bvanassche@acm.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
sgaud-quic pushed a commit that referenced this pull request Jan 31, 2026
Jamal Hadi Salim says:

====================
net/sched: teql: Enforce hierarchy placement

GangMin Kim <km.kim1503@gmail.com> managed to create a UAF on qfq by inserting
teql as a child qdisc and exploiting a qlen sync issue.
teql is not intended to be used as a child qdisc. Lets enforce that rule in
patch #1. Although patch #1 fixes the issue, we prevent another potential qlen
exploit in qfq in patch #2 by enforcing the child's active status is not
determined by inspecting the qlen. In patch #3 we add a tdc test case.
====================

Link: https://patch.msgid.link/20260114160243.913069-1-jhs@mojatatu.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
sgaud-quic pushed a commit that referenced this pull request Jan 31, 2026
Patch series "mm/hugetlb: fixes for PMD table sharing (incl.  using
mmu_gather)", v3.

One functional fix, one performance regression fix, and two related
comment fixes.

I cleaned up my prototype I recently shared [1] for the performance fix,
deferring most of the cleanups I had in the prototype to a later point. 
While doing that I identified the other things.

The goal of this patch set is to be backported to stable trees "fairly"
easily. At least patch #1 and #4.

Patch #1 fixes hugetlb_pmd_shared() not detecting any sharing
Patch #2 + #3 are simple comment fixes that patch #4 interacts with.
Patch #4 is a fix for the reported performance regression due to excessive
IPI broadcasts during fork()+exit().

The last patch is all about TLB flushes, IPIs and mmu_gather.
Read: complicated

There are plenty of cleanups in the future to be had + one reasonable
optimization on x86. But that's all out of scope for this series.

Runtime tested, with a focus on fixing the performance regression using
the original reproducer [2] on x86.


This patch (of 4):

We switched from (wrongly) using the page count to an independent shared
count.  Now, shared page tables have a refcount of 1 (excluding
speculative references) and instead use ptdesc->pt_share_count to identify
sharing.

We didn't convert hugetlb_pmd_shared(), so right now, we would never
detect a shared PMD table as such, because sharing/unsharing no longer
touches the refcount of a PMD table.

Page migration, like mbind() or migrate_pages() would allow for migrating
folios mapped into such shared PMD tables, even though the folios are not
exclusive.  In smaps we would account them as "private" although they are
"shared", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the
pagemap interface.

Fix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared().

Link: https://lkml.kernel.org/r/20251223214037.580860-1-david@kernel.org
Link: https://lkml.kernel.org/r/20251223214037.580860-2-david@kernel.org
Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [1]
Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [2]
Fixes: 59d9094 ("mm: hugetlb: independent PMD page table shared count")
Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Tested-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Uschakow, Stanislav" <suschako@amazon.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
sgaud-quic pushed a commit that referenced this pull request Jan 31, 2026
…itives

The "valid" readout delay between the two reads of the watchdog is larger
than the valid delta between the resulting watchdog and clocksource
intervals, which results in false positive watchdog results.

Assume TSC is the clocksource and HPET is the watchdog and both have a
uncertainty margin of 250us (default). The watchdog readout does:

  1) wdnow = read(HPET);
  2) csnow = read(TSC);
  3) wdend = read(HPET);

The valid window for the delta between #1 and #3 is calculated by the
uncertainty margins of the watchdog and the clocksource:

   m = 2 * watchdog.uncertainty_margin + cs.uncertainty margin;

which results in 750us for the TSC/HPET case.

The actual interval comparison uses a smaller margin:

   m = watchdog.uncertainty_margin + cs.uncertainty margin;

which results in 500us for the TSC/HPET case.

That means the following scenario will trigger the watchdog:

 Watchdog cycle N:

 1)       wdnow[N] = read(HPET);
 2)       csnow[N] = read(TSC);
 3)       wdend[N] = read(HPET);

Assume the delay between #1 and #2 is 100us and the delay between #1 and

 Watchdog cycle N + 1:

 4)       wdnow[N + 1] = read(HPET);
 5)       csnow[N + 1] = read(TSC);
 6)       wdend[N + 1] = read(HPET);

If the delay between #4 and #6 is within the 750us margin then any delay
between #4 and #5 which is larger than 600us will fail the interval check
and mark the TSC unstable because the intervals are calculated against the
previous value:

    wd_int = wdnow[N + 1] - wdnow[N];
    cs_int = csnow[N + 1] - csnow[N];

Putting the above delays in place this results in:

    cs_int = (wdnow[N + 1] + 610us) - (wdnow[N] + 100us);
 -> cs_int = wd_int + 510us;

which is obviously larger than the allowed 500us margin and results in
marking TSC unstable.

Fix this by using the same margin as the interval comparison. If the delay
between two watchdog reads is larger than that, then the readout was either
disturbed by interconnect congestion, NMIs or SMIs.

Fixes: 4ac1dd3 ("clocksource: Set cs_watchdog_read() checks based on .uncertainty_margin")
Reported-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/lkml/20250602223251.496591-1-daniel@quora.org/
Link: https://patch.msgid.link/87bjjxc9dq.ffs@tglx
sgaud-quic pushed a commit that referenced this pull request Feb 3, 2026
…alled from deferred_grow_zone()

Commit 3acb913 ("mm/mm_init: use deferred_init_memmap_chunk() in
deferred_grow_zone()") made deferred_grow_zone() call
deferred_init_memmap_chunk() within a pgdat_resize_lock() critical section
with irqs disabled.  It did check for irqs_disabled() in
deferred_init_memmap_chunk() to avoid calling cond_resched().  For a
PREEMPT_RT kernel build, however, spin_lock_irqsave() does not disable
interrupt but rcu_read_lock() is called.  This leads to the following bug
report.

  BUG: sleeping function called from invalid context at mm/mm_init.c:2091
  in_atomic(): 0, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
  preempt_count: 0, expected: 0
  RCU nest depth: 1, expected: 0
  3 locks held by swapper/0/1:
   #0: ffff80008471b7a0 (sched_domains_mutex){+.+.}-{4:4}, at: sched_domains_mutex_lock+0x28/0x40
   #1: ffff003bdfffef48 (&pgdat->node_size_lock){+.+.}-{3:3}, at: deferred_grow_zone+0x140/0x278
   #2: ffff800084acf600 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1b4/0x408
  CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Tainted: G        W           6.19.0-rc6-test #1 PREEMPT_{RT,(full)
}
  Tainted: [W]=WARN
  Call trace:
   show_stack+0x20/0x38 (C)
   dump_stack_lvl+0xdc/0xf8
   dump_stack+0x1c/0x28
   __might_resched+0x384/0x530
   deferred_init_memmap_chunk+0x560/0x688
   deferred_grow_zone+0x190/0x278
   _deferred_grow_zone+0x18/0x30
   get_page_from_freelist+0x780/0xf78
   __alloc_frozen_pages_noprof+0x1dc/0x348
   alloc_slab_page+0x30/0x110
   allocate_slab+0x98/0x2a0
   new_slab+0x4c/0x80
   ___slab_alloc+0x5a4/0x770
   __slab_alloc.constprop.0+0x88/0x1e0
   __kmalloc_node_noprof+0x2c0/0x598
   __sdt_alloc+0x3b8/0x728
   build_sched_domains+0xe0/0x1260
   sched_init_domains+0x14c/0x1c8
   sched_init_smp+0x9c/0x1d0
   kernel_init_freeable+0x218/0x358
   kernel_init+0x28/0x208
   ret_from_fork+0x10/0x20

Fix it adding a new argument to deferred_init_memmap_chunk() to explicitly
tell it if cond_resched() is allowed or not instead of relying on some
current state information which may vary depending on the exact kernel
configuration options that are enabled.

Link: https://lkml.kernel.org/r/20260122184343.546627-1-longman@redhat.com
Fixes: 3acb913 ("mm/mm_init: use deferred_init_memmap_chunk() in deferred_grow_zone()")
Signed-off-by: Waiman Long <longman@redhat.com>
Suggested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: David Hildenbrand <david@kernel.org>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: <stable@vger.kernrl.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
sgaud-quic pushed a commit that referenced this pull request Feb 3, 2026
There was a lockdep warning in sprd_gpio:

[    6.258269][T329@C6] [ BUG: Invalid wait context ]
[    6.258270][T329@C6] 6.18.0-android17-0-g30527ad7aaae-ab00009-4k #1 Tainted: G        W  OE
[    6.258272][T329@C6] -----------------------------
[    6.258273][T329@C6] modprobe/329 is trying to lock:
[    6.258275][T329@C6] ffffff8081c91690 (&sprd_gpio->lock){....}-{3:3}, at: sprd_gpio_irq_unmask+0x4c/0xa4 [gpio_sprd]
[    6.258282][T329@C6] other info that might help us debug this:
[    6.258283][T329@C6] context-{5:5}
[    6.258285][T329@C6] 3 locks held by modprobe/329:
[    6.258286][T329@C6]  #0: ffffff808baca108 (&dev->mutex){....}-{4:4}, at: __driver_attach+0xc4/0x204
[    6.258295][T329@C6]  #1: ffffff80965e7240 (request_class#4){+.+.}-{4:4}, at: __setup_irq+0x1cc/0x82c
[    6.258304][T329@C6]  #2: ffffff80965e70c8 (lock_class#4){....}-{2:2}, at: __setup_irq+0x21c/0x82c
[    6.258313][T329@C6] stack backtrace:
[    6.258314][T329@C6] CPU: 6 UID: 0 PID: 329 Comm: modprobe Tainted: G        W  OE       6.18.0-android17-0-g30527ad7aaae-ab00009-4k #1 PREEMPT  3ad5b0f45741a16e5838da790706e16ceb6717df
[    6.258316][T329@C6] Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
[    6.258317][T329@C6] Hardware name: Unisoc UMS9632-base Board (DT)
[    6.258318][T329@C6] Call trace:
[    6.258318][T329@C6]  show_stack+0x20/0x30 (C)
[    6.258321][T329@C6]  __dump_stack+0x28/0x3c
[    6.258324][T329@C6]  dump_stack_lvl+0xac/0xf0
[    6.258326][T329@C6]  dump_stack+0x18/0x3c
[    6.258329][T329@C6]  __lock_acquire+0x824/0x2c28
[    6.258331][T329@C6]  lock_acquire+0x148/0x2cc
[    6.258333][T329@C6]  _raw_spin_lock_irqsave+0x6c/0xb4
[    6.258334][T329@C6]  sprd_gpio_irq_unmask+0x4c/0xa4 [gpio_sprd 814535e93c6d8e0853c45c02eab0fa88a9da6487]
[    6.258337][T329@C6]  irq_startup+0x238/0x350
[    6.258340][T329@C6]  __setup_irq+0x504/0x82c
[    6.258342][T329@C6]  request_threaded_irq+0x118/0x184
[    6.258344][T329@C6]  devm_request_threaded_irq+0x94/0x120
[    6.258347][T329@C6]  sc8546_init_irq+0x114/0x170 [sc8546_charger 223586ccafc27439f7db4f95b0c8e6e882349a99]
[    6.258352][T329@C6]  sc8546_charger_probe+0x53c/0x5a0 [sc8546_charger 223586ccafc27439f7db4f95b0c8e6e882349a99]
[    6.258358][T329@C6]  i2c_device_probe+0x2c8/0x350
[    6.258361][T329@C6]  really_probe+0x1a8/0x46c
[    6.258363][T329@C6]  __driver_probe_device+0xa4/0x10c
[    6.258366][T329@C6]  driver_probe_device+0x44/0x1b4
[    6.258369][T329@C6]  __driver_attach+0xd0/0x204
[    6.258371][T329@C6]  bus_for_each_dev+0x10c/0x168
[    6.258373][T329@C6]  driver_attach+0x2c/0x3c
[    6.258376][T329@C6]  bus_add_driver+0x154/0x29c
[    6.258378][T329@C6]  driver_register+0x70/0x10c
[    6.258381][T329@C6]  i2c_register_driver+0x48/0xc8
[    6.258384][T329@C6]  init_module+0x28/0xfd8 [sc8546_charger 223586ccafc27439f7db4f95b0c8e6e882349a99]
[    6.258389][T329@C6]  do_one_initcall+0x128/0x42c
[    6.258392][T329@C6]  do_init_module+0x60/0x254
[    6.258395][T329@C6]  load_module+0x1054/0x1220
[    6.258397][T329@C6]  __arm64_sys_finit_module+0x240/0x35c
[    6.258400][T329@C6]  invoke_syscall+0x60/0xec
[    6.258402][T329@C6]  el0_svc_common+0xb0/0xe4
[    6.258405][T329@C6]  do_el0_svc+0x24/0x30
[    6.258407][T329@C6]  el0_svc+0x54/0x1c4
[    6.258409][T329@C6]  el0t_64_sync_handler+0x68/0xdc
[    6.258411][T329@C6]  el0t_64_sync+0x1c4/0x1c8

This is because the spin_lock would change to rt_mutex in PREEMPT_RT,
however the sprd_gpio->lock would use in hard-irq, this is unsafe.

So change the spin_lock_t to raw_spin_lock_t to use the spinlock
in hard-irq.

Signed-off-by: Xuewen Yan <xuewen.yan@unisoc.com>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20260126094209.9855-1-xuewen.yan@unisoc.com
[Bartosz: tweaked the commit message]
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
sgaud-quic pushed a commit that referenced this pull request Feb 3, 2026
Since the commit 25c6a5a ("net: phy: micrel: Dynamically control
external clock of KSZ PHY"), the clock of Micrel PHY has been enabled
by phy_driver::resume() and disabled by phy_driver::suspend(). However,
devm_clk_get_optional_enabled() is used in kszphy_probe(), so the clock
will automatically be disabled when the device is unbound from the bus.
Therefore, this could cause the clock to be disabled twice, resulting
in clk driver warnings.

For example, this issue can be reproduced on i.MX6ULL platform, and we
can see the following logs when removing the FEC MAC drivers.

$ echo 2188000.ethernet > /sys/bus/platform/drivers/fec/unbind
$ echo 20b4000.ethernet > /sys/bus/platform/drivers/fec/unbind
[  109.758207] ------------[ cut here ]------------
[  109.758240] WARNING: drivers/clk/clk.c:1188 at clk_core_disable+0xb4/0xd0, CPU#0: sh/639
[  109.771011] enet2_ref already disabled
[  109.793359] Call trace:
[  109.822006]  clk_core_disable from clk_disable+0x28/0x34
[  109.827340]  clk_disable from clk_disable_unprepare+0xc/0x18
[  109.833029]  clk_disable_unprepare from devm_clk_release+0x1c/0x28
[  109.839241]  devm_clk_release from devres_release_all+0x98/0x100
[  109.845278]  devres_release_all from device_unbind_cleanup+0xc/0x70
[  109.851571]  device_unbind_cleanup from device_release_driver_internal+0x1a4/0x1f4
[  109.859170]  device_release_driver_internal from bus_remove_device+0xbc/0xe4
[  109.866243]  bus_remove_device from device_del+0x140/0x458
[  109.871757]  device_del from phy_mdio_device_remove+0xc/0x24
[  109.877452]  phy_mdio_device_remove from mdiobus_unregister+0x40/0xac
[  109.883918]  mdiobus_unregister from fec_enet_mii_remove+0x40/0x78
[  109.890125]  fec_enet_mii_remove from fec_drv_remove+0x4c/0x158
[  109.896076]  fec_drv_remove from device_release_driver_internal+0x17c/0x1f4
[  109.962748] WARNING: drivers/clk/clk.c:1047 at clk_core_unprepare+0xfc/0x13c, CPU#0: sh/639
[  109.975805] enet2_ref already unprepared
[  110.002866] Call trace:
[  110.031758]  clk_core_unprepare from clk_unprepare+0x24/0x2c
[  110.037440]  clk_unprepare from devm_clk_release+0x1c/0x28
[  110.042957]  devm_clk_release from devres_release_all+0x98/0x100
[  110.048989]  devres_release_all from device_unbind_cleanup+0xc/0x70
[  110.055280]  device_unbind_cleanup from device_release_driver_internal+0x1a4/0x1f4
[  110.062877]  device_release_driver_internal from bus_remove_device+0xbc/0xe4
[  110.069950]  bus_remove_device from device_del+0x140/0x458
[  110.075469]  device_del from phy_mdio_device_remove+0xc/0x24
[  110.081165]  phy_mdio_device_remove from mdiobus_unregister+0x40/0xac
[  110.087632]  mdiobus_unregister from fec_enet_mii_remove+0x40/0x78
[  110.093836]  fec_enet_mii_remove from fec_drv_remove+0x4c/0x158
[  110.099782]  fec_drv_remove from device_release_driver_internal+0x17c/0x1f4

After analyzing the process of removing the FEC driver, as shown below,
it can be seen that the clock was disabled twice by the PHY driver.

fec_drv_remove()
  --> fec_enet_close()
    --> phy_stop()
      --> phy_suspend()
        --> kszphy_suspend() #1 The clock is disabled
  --> fec_enet_mii_remove()
    --> mdiobus_unregister()
      --> phy_mdio_device_remove()
        --> device_del()
          --> devm_clk_release() #2 The clock is disabled again

Therefore, devm_clk_get_optional() is used to fix the above issue. And
to avoid the issue mentioned by the commit 9853294 ("net: phy:
micrel: use devm_clk_get_optional_enabled for the rmii-ref clock"), the
clock is enabled by clk_prepare_enable() to get the correct clock rate.

Fixes: 25c6a5a ("net: phy: micrel: Dynamically control external clock of KSZ PHY")
Signed-off-by: Wei Fang <wei.fang@nxp.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20260126081544.983517-1-wei.fang@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
zhuhangtian pushed a commit to zhuhangtian/kernel-topics that referenced this pull request Feb 4, 2026
In ath12k_mac_op_link_sta_statistics(), the atomic context scope
introduced by dp_lock also covers firmware stats request. Since that
request could block, below issue is hit:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:575
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6866, name: iw
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
3 locks held by iw/6866:
 #0:[...]
 qualcomm-linux#1:[...]
 qualcomm-linux#2: ffff9748f43230c8 (&dp->dp_lock){+.-.}-{3:3}, at:
ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Preemption disabled at:
[<ffffffffc0349656>] ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Call Trace:
 <TASK>
 show_stack
 dump_stack_lvl
 dump_stack
 __might_resched.cold
 __might_sleep
 __mutex_lock
 mutex_lock_nested
 ath12k_mac_get_fw_stats
 ath12k_mac_op_link_sta_statistics
 </TASK>

Since firmware stats request doesn't require protection from dp_lock, move
it outside to fix this issue.

While moving, also refine that code hunk to make function parameters get
populated when really necessary.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20251119-ath12k-ng-sleep-in-atomic-v1-1-5d1a726597db@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
zhuhangtian pushed a commit to zhuhangtian/kernel-topics that referenced this pull request Feb 4, 2026
In ath12k_mac_op_link_sta_statistics(), the atomic context scope
introduced by dp_lock also covers firmware stats request. Since that
request could block, below issue is hit:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:575
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6866, name: iw
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
3 locks held by iw/6866:
 #0:[...]
 qualcomm-linux#1:[...]
 qualcomm-linux#2: ffff9748f43230c8 (&dp->dp_lock){+.-.}-{3:3}, at:
ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Preemption disabled at:
[<ffffffffc0349656>] ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Call Trace:
 <TASK>
 show_stack
 dump_stack_lvl
 dump_stack
 __might_resched.cold
 __might_sleep
 __mutex_lock
 mutex_lock_nested
 ath12k_mac_get_fw_stats
 ath12k_mac_op_link_sta_statistics
 </TASK>

Since firmware stats request doesn't require protection from dp_lock, move
it outside to fix this issue.

While moving, also refine that code hunk to make function parameters get
populated when really necessary.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20251119-ath12k-ng-sleep-in-atomic-v1-1-5d1a726597db@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
miaoqing-quic pushed a commit that referenced this pull request Feb 4, 2026
In ath12k_mac_op_link_sta_statistics(), the atomic context scope
introduced by dp_lock also covers firmware stats request. Since that
request could block, below issue is hit:

BUG: sleeping function called from invalid context at kernel/locking/mutex.c:575
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 6866, name: iw
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
3 locks held by iw/6866:
 #0:[...]
 #1:[...]
 #2: ffff9748f43230c8 (&dp->dp_lock){+.-.}-{3:3}, at:
ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Preemption disabled at:
[<ffffffffc0349656>] ath12k_mac_op_link_sta_statistics+0xc6/0x380 [ath12k]
Call Trace:
 <TASK>
 show_stack
 dump_stack_lvl
 dump_stack
 __might_resched.cold
 __might_sleep
 __mutex_lock
 mutex_lock_nested
 ath12k_mac_get_fw_stats
 ath12k_mac_op_link_sta_statistics
 </TASK>

Since firmware stats request doesn't require protection from dp_lock, move
it outside to fix this issue.

While moving, also refine that code hunk to make function parameters get
populated when really necessary.

Tested-on: WCN7850 hw2.0 PCI WLAN.HMT.1.1.c5-00302-QCAHMTSWPL_V1.0_V2.0_SILICONZ-1.115823.3

Signed-off-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Reviewed-by: Vasanthakumar Thiagarajan <vasanthakumar.thiagarajan@oss.qualcomm.com>
Link: https://patch.msgid.link/20251119-ath12k-ng-sleep-in-atomic-v1-1-5d1a726597db@oss.qualcomm.com
Signed-off-by: Jeff Johnson <jeff.johnson@oss.qualcomm.com>
abelvesa pushed a commit that referenced this pull request Feb 17, 2026
Patch series "mm/hugetlb: fixes for PMD table sharing (incl.  using
mmu_gather)", v3.

One functional fix, one performance regression fix, and two related
comment fixes.

I cleaned up my prototype I recently shared [1] for the performance fix,
deferring most of the cleanups I had in the prototype to a later point. 
While doing that I identified the other things.

The goal of this patch set is to be backported to stable trees "fairly"
easily. At least patch #1 and #4.

Patch #1 fixes hugetlb_pmd_shared() not detecting any sharing
Patch #2 + #3 are simple comment fixes that patch #4 interacts with.
Patch #4 is a fix for the reported performance regression due to excessive
IPI broadcasts during fork()+exit().

The last patch is all about TLB flushes, IPIs and mmu_gather.
Read: complicated

There are plenty of cleanups in the future to be had + one reasonable
optimization on x86. But that's all out of scope for this series.

Runtime tested, with a focus on fixing the performance regression using
the original reproducer [2] on x86.


This patch (of 4):

We switched from (wrongly) using the page count to an independent shared
count.  Now, shared page tables have a refcount of 1 (excluding
speculative references) and instead use ptdesc->pt_share_count to identify
sharing.

We didn't convert hugetlb_pmd_shared(), so right now, we would never
detect a shared PMD table as such, because sharing/unsharing no longer
touches the refcount of a PMD table.

Page migration, like mbind() or migrate_pages() would allow for migrating
folios mapped into such shared PMD tables, even though the folios are not
exclusive.  In smaps we would account them as "private" although they are
"shared", and we would be wrongly setting the PM_MMAP_EXCLUSIVE in the
pagemap interface.

Fix it by properly using ptdesc_pmd_is_shared() in hugetlb_pmd_shared().

Link: https://lkml.kernel.org/r/20251223214037.580860-1-david@kernel.org
Link: https://lkml.kernel.org/r/20251223214037.580860-2-david@kernel.org
Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [1]
Link: https://lore.kernel.org/all/8cab934d-4a56-44aa-b641-bfd7e23bd673@kernel.org/ [2]
Fixes: 59d9094 ("mm: hugetlb: independent PMD page table shared count")
Signed-off-by: David Hildenbrand (Red Hat) <david@kernel.org>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Lance Yang <lance.yang@linux.dev>
Tested-by: Lance Yang <lance.yang@linux.dev>
Reviewed-by: Harry Yoo <harry.yoo@oracle.com>
Tested-by: Laurence Oberman <loberman@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Oscar Salvador <osalvador@suse.de>
Cc: Liu Shixin <liushixin2@huawei.com>
Cc: Uschakow, Stanislav" <suschako@amazon.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
abelvesa pushed a commit that referenced this pull request Feb 17, 2026
Patch series "kallsyms: Prevent invalid access when showing module
buildid", v3.

We have seen nested crashes in __sprint_symbol(), see below.  They seem to
be caused by an invalid pointer to "buildid".  This patchset cleans up
kallsyms code related to module buildid and fixes this invalid access when
printing backtraces.

I made an audit of __sprint_symbol() and found several situations
when the buildid might be wrong:

  + bpf_address_lookup() does not set @modbuildid

  + ftrace_mod_address_lookup() does not set @modbuildid

  + __sprint_symbol() does not take rcu_read_lock and
    the related struct module might get removed before
    mod->build_id is printed.

This patchset solves these problems:

  + 1st, 2nd patches are preparatory
  + 3rd, 4th, 6th patches fix the above problems
  + 5th patch cleans up a suspicious initialization code.

This is the backtrace, we have seen. But it is not really important.
The problems fixed by the patchset are obvious:

  crash64> bt [62/2029]
  PID: 136151 TASK: ffff9f6c981d4000 CPU: 367 COMMAND: "btrfs"
  #0 [ffffbdb687635c28] machine_kexec at ffffffffb4c845b3
  #1 [ffffbdb687635c80] __crash_kexec at ffffffffb4d86a6a
  #2 [ffffbdb687635d08] hex_string at ffffffffb51b3b61
  #3 [ffffbdb687635d40] crash_kexec at ffffffffb4d87964
  #4 [ffffbdb687635d50] oops_end at ffffffffb4c41fc8
  #5 [ffffbdb687635d70] do_trap at ffffffffb4c3e49a
  #6 [ffffbdb687635db8] do_error_trap at ffffffffb4c3e6a4
  #7 [ffffbdb687635df8] exc_stack_segment at ffffffffb5666b33
  #8 [ffffbdb687635e20] asm_exc_stack_segment at ffffffffb5800cf9
  ...


This patch (of 7)

The function kallsyms_lookup_buildid() initializes the given @namebuf by
clearing the first and the last byte.  It is not clear why.

The 1st byte makes sense because some callers ignore the return code and
expect that the buffer contains a valid string, for example:

  - function_stat_show()
    - kallsyms_lookup()
      - kallsyms_lookup_buildid()

The initialization of the last byte does not make much sense because it
can later be overwritten.  Fortunately, it seems that all called functions
behave correctly:

  -  kallsyms_expand_symbol() explicitly adds the trailing '\0'
     at the end of the function.

  - All *__address_lookup() functions either use the safe strscpy()
    or they do not touch the buffer at all.

Document the reason for clearing the first byte.  And remove the useless
initialization of the last byte.

Link: https://lkml.kernel.org/r/20251128135920.217303-2-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkman <daniel@iogearbox.net>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Kees Cook <kees@kernel.org>
Cc: Luis Chamberalin <mcgrof@kernel.org>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Petr Pavlu <petr.pavlu@suse.com>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Daniel Gomez <da.gomez@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
abelvesa pushed a commit that referenced this pull request Feb 17, 2026
…ked_inode()

In btrfs_read_locked_inode() we are calling btrfs_init_file_extent_tree()
while holding a path with a read locked leaf from a subvolume tree, and
btrfs_init_file_extent_tree() may do a GFP_KERNEL allocation, which can
trigger reclaim.

This can create a circular lock dependency which lockdep warns about with
the following splat:

   [6.1433] ======================================================
   [6.1574] WARNING: possible circular locking dependency detected
   [6.1583] 6.18.0+ #4 Tainted: G     U
   [6.1591] ------------------------------------------------------
   [6.1599] kswapd0/117 is trying to acquire lock:
   [6.1606] ffff8d9b6333c5b8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1625]
            but task is already holding lock:
   [6.1633] ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
   [6.1646]
            which lock already depends on the new lock.

   [6.1657]
            the existing dependency chain (in reverse order) is:
   [6.1667]
            -> #2 (fs_reclaim){+.+.}-{0:0}:
   [6.1677]        fs_reclaim_acquire+0x9d/0xd0
   [6.1685]        __kmalloc_cache_noprof+0x59/0x750
   [6.1694]        btrfs_init_file_extent_tree+0x90/0x100
   [6.1702]        btrfs_read_locked_inode+0xc3/0x6b0
   [6.1710]        btrfs_iget+0xbb/0xf0
   [6.1716]        btrfs_lookup_dentry+0x3c5/0x8e0
   [6.1724]        btrfs_lookup+0x12/0x30
   [6.1731]        lookup_open.isra.0+0x1aa/0x6a0
   [6.1739]        path_openat+0x5f7/0xc60
   [6.1746]        do_filp_open+0xd6/0x180
   [6.1753]        do_sys_openat2+0x8b/0xe0
   [6.1760]        __x64_sys_openat+0x54/0xa0
   [6.1768]        do_syscall_64+0x97/0x3e0
   [6.1776]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [6.1784]
            -> #1 (btrfs-tree-00){++++}-{3:3}:
   [6.1794]        lock_release+0x127/0x2a0
   [6.1801]        up_read+0x1b/0x30
   [6.1808]        btrfs_search_slot+0x8e0/0xff0
   [6.1817]        btrfs_lookup_inode+0x52/0xd0
   [6.1825]        __btrfs_update_delayed_inode+0x73/0x520
   [6.1833]        btrfs_commit_inode_delayed_inode+0x11a/0x120
   [6.1842]        btrfs_log_inode+0x608/0x1aa0
   [6.1849]        btrfs_log_inode_parent+0x249/0xf80
   [6.1857]        btrfs_log_dentry_safe+0x3e/0x60
   [6.1865]        btrfs_sync_file+0x431/0x690
   [6.1872]        do_fsync+0x39/0x80
   [6.1879]        __x64_sys_fsync+0x13/0x20
   [6.1887]        do_syscall_64+0x97/0x3e0
   [6.1894]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [6.1903]
            -> #0 (&delayed_node->mutex){+.+.}-{3:3}:
   [6.1913]        __lock_acquire+0x15e9/0x2820
   [6.1920]        lock_acquire+0xc9/0x2d0
   [6.1927]        __mutex_lock+0xcc/0x10a0
   [6.1934]        __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1944]        btrfs_evict_inode+0x20b/0x4b0
   [6.1952]        evict+0x15a/0x2f0
   [6.1958]        prune_icache_sb+0x91/0xd0
   [6.1966]        super_cache_scan+0x150/0x1d0
   [6.1974]        do_shrink_slab+0x155/0x6f0
   [6.1981]        shrink_slab+0x48e/0x890
   [6.1988]        shrink_one+0x11a/0x1f0
   [6.1995]        shrink_node+0xbfd/0x1320
   [6.1002]        balance_pgdat+0x67f/0xc60
   [6.1321]        kswapd+0x1dc/0x3e0
   [6.1643]        kthread+0xff/0x240
   [6.1965]        ret_from_fork+0x223/0x280
   [6.1287]        ret_from_fork_asm+0x1a/0x30
   [6.1616]
            other info that might help us debug this:

   [6.1561] Chain exists of:
              &delayed_node->mutex --> btrfs-tree-00 --> fs_reclaim

   [6.1503]  Possible unsafe locking scenario:

   [6.1110]        CPU0                    CPU1
   [6.1411]        ----                    ----
   [6.1707]   lock(fs_reclaim);
   [6.1998]                                lock(btrfs-tree-00);
   [6.1291]                                lock(fs_reclaim);
   [6.1581]   lock(&delayed_node->mutex);
   [6.1874]
             *** DEADLOCK ***

   [6.1716] 2 locks held by kswapd0/117:
   [6.1999]  #0: ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
   [6.1294]  #1: ffff8d998344b0e0 (&type->s_umount_key#40){++++}- {3:3}, at: super_cache_scan+0x37/0x1d0
   [6.1596]
            stack backtrace:
   [6.1183] CPU: 11 UID: 0 PID: 117 Comm: kswapd0 Tainted: G     U 6.18.0+ #4 PREEMPT(lazy)
   [6.1185] Tainted: [U]=USER
   [6.1186] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
   [6.1187] Call Trace:
   [6.1187]  <TASK>
   [6.1189]  dump_stack_lvl+0x6e/0xa0
   [6.1192]  print_circular_bug.cold+0x17a/0x1c0
   [6.1194]  check_noncircular+0x175/0x190
   [6.1197]  __lock_acquire+0x15e9/0x2820
   [6.1200]  lock_acquire+0xc9/0x2d0
   [6.1201]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1204]  __mutex_lock+0xcc/0x10a0
   [6.1206]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1208]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1211]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1213]  __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1215]  btrfs_evict_inode+0x20b/0x4b0
   [6.1217]  ? lock_acquire+0xc9/0x2d0
   [6.1220]  evict+0x15a/0x2f0
   [6.1222]  prune_icache_sb+0x91/0xd0
   [6.1224]  super_cache_scan+0x150/0x1d0
   [6.1226]  do_shrink_slab+0x155/0x6f0
   [6.1228]  shrink_slab+0x48e/0x890
   [6.1229]  ? shrink_slab+0x2d2/0x890
   [6.1231]  shrink_one+0x11a/0x1f0
   [6.1234]  shrink_node+0xbfd/0x1320
   [6.1236]  ? shrink_node+0xa2d/0x1320
   [6.1236]  ? shrink_node+0xbd3/0x1320
   [6.1239]  ? balance_pgdat+0x67f/0xc60
   [6.1239]  balance_pgdat+0x67f/0xc60
   [6.1241]  ? finish_task_switch.isra.0+0xc4/0x2a0
   [6.1246]  kswapd+0x1dc/0x3e0
   [6.1247]  ? __pfx_autoremove_wake_function+0x10/0x10
   [6.1249]  ? __pfx_kswapd+0x10/0x10
   [6.1250]  kthread+0xff/0x240
   [6.1251]  ? __pfx_kthread+0x10/0x10
   [6.1253]  ret_from_fork+0x223/0x280
   [6.1255]  ? __pfx_kthread+0x10/0x10
   [6.1257]  ret_from_fork_asm+0x1a/0x30
   [6.1260]  </TASK>

This is because:

1) The fsync task is holding an inode's delayed node mutex (for a
   directory) while calling __btrfs_update_delayed_inode() and that needs
   to do a search on the subvolume's btree (therefore read lock some
   extent buffers);

2) The lookup task, at btrfs_lookup(), triggered reclaim with the
   GFP_KERNEL allocation done by btrfs_init_file_extent_tree() while
   holding a read lock on a subvolume leaf;

3) The reclaim triggered kswapd which is doing inode eviction for the
   directory inode the fsync task is using as an argument to
   btrfs_commit_inode_delayed_inode() - but in that call chain we are
   trying to read lock the same leaf that the lookup task is holding
   while calling btrfs_init_file_extent_tree() and doing the GFP_KERNEL
   allocation.

Fix this by calling btrfs_init_file_extent_tree() after we don't need the
path anymore and release it in btrfs_read_locked_inode().

Reported-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://lore.kernel.org/linux-btrfs/6e55113a22347c3925458a5d840a18401a38b276.camel@linux.intel.com/
Fixes: 8679d26 ("btrfs: initialize inode::file_extent_tree after i_mode has been set")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
sgaud-quic pushed a commit that referenced this pull request Feb 23, 2026
On the THUNDEROBOT ZERO laptop, the second NVMe slot and the discrete
NVIDIA GPU are both controlled by power-resource PXP. Due to the SSDT table
bug (lack of reference), PXP will be shut dow as an "unused" power resource
during initialization, making the NVMe slot #2 + NVIDIA both inaccessible.

This issue was introduced by commit a1224f3 ("ACPI: PM: Check
states of power resources during initialization"). Here are test
results on the three consecutive commits:

(bad again!) a1224f3 ACPI: PM: Check states of power resources during initialization
(good) bc28368 ACPI: PM: Do not turn off power resources in unknown state
(bad) 519d819 Linux 5.15-rc6

On commit bc28368 ("ACPI: PM: Do not turn off power resources in
unknown state") this was not an issue because the power resource state
left UNKNOWN thus being ignored.

See also commit 9b04d99 ("ACPI: PM: Do not turn of unused power
resources on the Toshiba Click Mini") which is another almost identical
case to this one.

Fixes: a1224f3 ("ACPI: PM: Check states of power resources during initialization")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221087
Signed-off-by: Zhai Can <bczhc0@126.com>
Link: https://patch.msgid.link/20260214161452.2849346-1-bczhc0@126.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
sgaud-quic pushed a commit that referenced this pull request Feb 23, 2026
With PREEMPT_RT as potential configuration option, spinlock_t is now
considered as a sleeping lock, and thus might cause issues when used in
an atomic context. But even with PREEMPT_RT as potential configuration
option, raw_spinlock_t remains as a true spinning lock/atomic context.
This creates potential issues with the s390 debug/tracing feature. The
functions to trace errors are called in various contexts, including
under lock of raw_spinlock_t, and thus the used spinlock_t in each debug
area is in violation of the locking semantics.

Here are two examples involving failing PCI Read accesses that are
traced while holding `pci_lock` in `drivers/pci/access.c`:

=============================
[ BUG: Invalid wait context ]
6.19.0-devel #18 Not tainted
-----------------------------
bash/3833 is trying to lock:
0000027790baee30 (&rc->lock){-.-.}-{3:3}, at: debug_event_common+0xfc/0x300
other info that might help us debug this:
context-{5:5}
5 locks held by bash/3833:
 #0: 0000027efbb29450 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x7c/0xf0
 #1: 00000277f0504a90 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x13e/0x260
 #2: 00000277beed8c18 (kn->active#339){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x164/0x260
 #3: 00000277e9859190 (&dev->mutex){....}-{4:4}, at: pci_dev_lock+0x2e/0x40
 #4: 00000383068a7708 (pci_lock){....}-{2:2}, at: pci_bus_read_config_dword+0x4a/0xb0
stack backtrace:
CPU: 6 UID: 0 PID: 3833 Comm: bash Kdump: loaded Not tainted 6.19.0-devel #18 PREEMPTLAZY
Hardware name: IBM 9175 ME1 701 (LPAR)
Call Trace:
 [<00000383048afec2>] dump_stack_lvl+0xa2/0xe8
 [<00000383049ba166>] __lock_acquire+0x816/0x1660
 [<00000383049bb1fa>] lock_acquire+0x24a/0x370
 [<00000383059e3860>] _raw_spin_lock_irqsave+0x70/0xc0
 [<00000383048bbb6c>] debug_event_common+0xfc/0x300
 [<0000038304900b0a>] __zpci_load+0x17a/0x1f0
 [<00000383048fad88>] pci_read+0x88/0xd0
 [<00000383054cbce0>] pci_bus_read_config_dword+0x70/0xb0
 [<00000383054d55e4>] pci_dev_wait+0x174/0x290
 [<00000383054d5a3e>] __pci_reset_function_locked+0xfe/0x170
 [<00000383054d9b30>] pci_reset_function+0xd0/0x100
 [<00000383054ee21a>] reset_store+0x5a/0x80
 [<0000038304e98758>] kernfs_fop_write_iter+0x1e8/0x260
 [<0000038304d995da>] new_sync_write+0x13a/0x180
 [<0000038304d9c5d0>] vfs_write+0x200/0x330
 [<0000038304d9c88c>] ksys_write+0x7c/0xf0
 [<00000383059cfa80>] __do_syscall+0x210/0x500
 [<00000383059e4c06>] system_call+0x6e/0x90
INFO: lockdep is turned off.

=============================
[ BUG: Invalid wait context ]
6.19.0-devel #3 Not tainted
-----------------------------
bash/6861 is trying to lock:
0000009da05c7430 (&rc->lock){-.-.}-{3:3}, at: debug_event_common+0xfc/0x300
other info that might help us debug this:
context-{5:5}
5 locks held by bash/6861:
 #0: 000000acff404450 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x7c/0xf0
 #1: 000000acff41c490 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x13e/0x260
 #2: 0000009da36937d8 (kn->active#75){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x164/0x260
 #3: 0000009dd15250d0 (&zdev->state_lock){+.+.}-{4:4}, at: enable_slot+0x2e/0xc0
 #4: 000001a19682f708 (pci_lock){....}-{2:2}, at: pci_bus_read_config_byte+0x42/0xa0
stack backtrace:
CPU: 16 UID: 0 PID: 6861 Comm: bash Kdump: loaded Not tainted 6.19.0-devel #3 PREEMPTLAZY
Hardware name: IBM 9175 ME1 701 (LPAR)
Call Trace:
 [<000001a194837ec2>] dump_stack_lvl+0xa2/0xe8
 [<000001a194942166>] __lock_acquire+0x816/0x1660
 [<000001a1949431fa>] lock_acquire+0x24a/0x370
 [<000001a19596b810>] _raw_spin_lock_irqsave+0x70/0xc0
 [<000001a194843b6c>] debug_event_common+0xfc/0x300
 [<000001a194888b0a>] __zpci_load+0x17a/0x1f0
 [<000001a194882d88>] pci_read+0x88/0xd0
 [<000001a195453b88>] pci_bus_read_config_byte+0x68/0xa0
 [<000001a195457bc2>] pci_setup_device+0x62/0xad0
 [<000001a195458e70>] pci_scan_single_device+0x90/0xe0
 [<000001a19488a0f6>] zpci_bus_scan_device+0x46/0x80
 [<000001a19547f958>] enable_slot+0x98/0xc0
 [<000001a19547f134>] power_write_file+0xc4/0x110
 [<000001a194e20758>] kernfs_fop_write_iter+0x1e8/0x260
 [<000001a194d215da>] new_sync_write+0x13a/0x180
 [<000001a194d245d0>] vfs_write+0x200/0x330
 [<000001a194d2488c>] ksys_write+0x7c/0xf0
 [<000001a195957a30>] __do_syscall+0x210/0x500
 [<000001a19596cbb6>] system_call+0x6e/0x90
INFO: lockdep is turned off.

Since it is desired to keep it possible to create trace records in most
situations, including this particular case (failing PCI config space
accesses are relevant), convert the used spinlock_t in `struct
debug_info` to raw_spinlock_t.

The impact is small, as the debug area lock only protects bounded memory
access without external dependencies, apart from one function
debug_set_size() where kfree() is implicitly called with the lock held.
Move debug_info_free() out of this lock, to keep remove this external
dependency.

Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
sgaud-quic pushed a commit that referenced this pull request Feb 23, 2026
The io_zcrx_put_niov_uref() function uses a non-atomic
check-then-decrement pattern (atomic_read followed by separate
atomic_dec) to manipulate user_refs. This is serialized against other
callers by rq_lock, but io_zcrx_scrub() modifies the same counter with
atomic_xchg() WITHOUT holding rq_lock.

On SMP systems, the following race exists:

  CPU0 (refill, holds rq_lock)          CPU1 (scrub, no rq_lock)
  put_niov_uref:
    atomic_read(uref) - 1
    // window opens
                                        atomic_xchg(uref, 0) - 1
                                        return_niov_freelist(niov) [PUSH #1]
    // window closes
    atomic_dec(uref) - wraps to -1
    returns true
    return_niov(niov)
    return_niov_freelist(niov)           [PUSH #2: DOUBLE-FREE]

The same niov is pushed to the freelist twice, causing free_count to
exceed nr_iovs. Subsequent freelist pushes then perform an out-of-bounds
write (a u32 value) past the kvmalloc'd freelist array into the adjacent
slab object.

Fix this by replacing the non-atomic read-then-dec in
io_zcrx_put_niov_uref() with an atomic_try_cmpxchg loop that atomically
tests and decrements user_refs. This makes the operation safe against
concurrent atomic_xchg from scrub without requiring scrub to acquire
rq_lock.

Fixes: 34a3e60 ("io_uring/zcrx: implement zerocopy receive pp memory provider")
Cc: stable@vger.kernel.org
Signed-off-by: Kai Aizen <kai@snailsploit.com>
[pavel: removed a warning and a comment]
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
sgaud-quic pushed a commit that referenced this pull request Feb 23, 2026
The ALB RX path may access rx_hashtbl concurrently with bond
teardown. During rapid bond up/down cycles, rlb_deinitialize()
frees rx_hashtbl while RX handlers are still running, leading
to a null pointer dereference detected by KASAN.

However, the root cause is that rlb_arp_recv() can still be accessed
after setting recv_probe to NULL, which is actually a use-after-free
(UAF) issue. That is the reason for using the referenced commit in the
Fixes tag.

[  214.174138] Oops: general protection fault, probably for non-canonical address 0xdffffc000000001d: 0000 [#1] SMP KASAN PTI
[  214.186478] KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef]
[  214.194933] CPU: 30 UID: 0 PID: 2375 Comm: ping Kdump: loaded Not tainted 6.19.0-rc8+ #2 PREEMPT(voluntary)
[  214.205907] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.14.0 01/14/2022
[  214.214357] RIP: 0010:rlb_arp_recv+0x505/0xab0 [bonding]
[  214.220320] Code: 0f 85 2b 05 00 00 48 b8 00 00 00 00 00 fc ff df 40 0f b6 ed 48 c1 e5 06 49 03 ad 78 01 00 00 48 8d 7d 28 48 89 fa 48 c1 ea 03 <0f> b6
 04 02 84 c0 74 06 0f 8e 12 05 00 00 80 7d 28 00 0f 84 8c 00
[  214.241280] RSP: 0018:ffffc900073d8870 EFLAGS: 00010206
[  214.247116] RAX: dffffc0000000000 RBX: ffff888168556822 RCX: ffff88816855681e
[  214.255082] RDX: 000000000000001d RSI: dffffc0000000000 RDI: 00000000000000e8
[  214.263048] RBP: 00000000000000c0 R08: 0000000000000002 R09: ffffed11192021c8
[  214.271013] R10: ffff8888c9010e43 R11: 0000000000000001 R12: 1ffff92000e7b119
[  214.278978] R13: ffff8888c9010e00 R14: ffff888168556822 R15: ffff888168556810
[  214.286943] FS:  00007f85d2d9cb80(0000) GS:ffff88886ccb3000(0000) knlGS:0000000000000000
[  214.295966] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  214.302380] CR2: 00007f0d047b5e34 CR3: 00000008a1c2e002 CR4: 00000000001726f0
[  214.310347] Call Trace:
[  214.313070]  <IRQ>
[  214.315318]  ? __pfx_rlb_arp_recv+0x10/0x10 [bonding]
[  214.320975]  bond_handle_frame+0x166/0xb60 [bonding]
[  214.326537]  ? __pfx_bond_handle_frame+0x10/0x10 [bonding]
[  214.332680]  __netif_receive_skb_core.constprop.0+0x576/0x2710
[  214.339199]  ? __pfx_arp_process+0x10/0x10
[  214.343775]  ? sched_balance_find_src_group+0x98/0x630
[  214.349513]  ? __pfx___netif_receive_skb_core.constprop.0+0x10/0x10
[  214.356513]  ? arp_rcv+0x307/0x690
[  214.360311]  ? __pfx_arp_rcv+0x10/0x10
[  214.364499]  ? __lock_acquire+0x58c/0xbd0
[  214.368975]  __netif_receive_skb_one_core+0xae/0x1b0
[  214.374518]  ? __pfx___netif_receive_skb_one_core+0x10/0x10
[  214.380743]  ? lock_acquire+0x10b/0x140
[  214.385026]  process_backlog+0x3f1/0x13a0
[  214.389502]  ? process_backlog+0x3aa/0x13a0
[  214.394174]  __napi_poll.constprop.0+0x9f/0x370
[  214.399233]  net_rx_action+0x8c1/0xe60
[  214.403423]  ? __pfx_net_rx_action+0x10/0x10
[  214.408193]  ? lock_acquire.part.0+0xbd/0x260
[  214.413058]  ? sched_clock_cpu+0x6c/0x540
[  214.417540]  ? mark_held_locks+0x40/0x70
[  214.421920]  handle_softirqs+0x1fd/0x860
[  214.426302]  ? __pfx_handle_softirqs+0x10/0x10
[  214.431264]  ? __neigh_event_send+0x2d6/0xf50
[  214.436131]  do_softirq+0xb1/0xf0
[  214.439830]  </IRQ>

The issue is reproducible by repeatedly running
ip link set bond0 up/down while receiving ARP messages, where
rlb_arp_recv() can race with rlb_deinitialize() and dereference
a freed rx_hashtbl entry.

Fix this by setting recv_probe to NULL and then calling
synchronize_net() to wait for any concurrent RX processing to finish.
This ensures that no RX handler can access rx_hashtbl after it is freed
in bond_alb_deinitialize().

Reported-by: Liang Li <liali@redhat.com>
Fixes: 3aba891 ("bonding: move processing of recv handlers into handle_frame()")
Reviewed-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Jay Vosburgh <jv@jvosburgh.net>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/20260218060919.101574-1-liuhangbin@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
Jakub reported an MPTCP deadlock at fallback time:

 WARNING: possible recursive locking detected
 6.18.0-rc7-virtme #1 Not tainted
 --------------------------------------------
 mptcp_connect/20858 is trying to acquire lock:
 ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280

 but task is already holding lock:
 ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&msk->fallback_lock);
   lock(&msk->fallback_lock);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 3 locks held by mptcp_connect/20858:
  #0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0
  #1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0
  #2: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0

 stack backtrace:
 CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full)
 Hardware name: Bochs, BIOS Bochs 01/01/2011
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6f/0xa0
  print_deadlock_bug.cold+0xc0/0xcd
  validate_chain+0x2ff/0x5f0
  __lock_acquire+0x34c/0x740
  lock_acquire.part.0+0xbc/0x260
  _raw_spin_lock_bh+0x38/0x50
  __mptcp_try_fallback+0xd8/0x280
  mptcp_sendmsg_frag+0x16c2/0x3050
  __mptcp_retrans+0x421/0xaa0
  mptcp_release_cb+0x5aa/0xa70
  release_sock+0xab/0x1d0
  mptcp_sendmsg+0xd5b/0x1bc0
  sock_write_iter+0x281/0x4d0
  new_sync_write+0x3c5/0x6f0
  vfs_write+0x65e/0xbb0
  ksys_write+0x17e/0x200
  do_syscall_64+0xbb/0xfd0
  entry_SYSCALL_64_after_hwframe+0x4b/0x53
 RIP: 0033:0x7fa5627cbc5e
 Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa
 RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e
 RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005
 RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920
 R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c

The packet scheduler could attempt a reinjection after receiving an
MP_FAIL and before the infinite map has been transmitted, causing a
deadlock since MPTCP needs to do the reinjection atomically from WRT
fallback.

Address the issue explicitly avoiding the reinjection in the critical
scenario. Note that this is the only fallback critical section that
could potentially send packets and hit the double-lock.

Reported-by: Jakub Kicinski <kuba@kernel.org>
Closes: https://netdev-ctrl.bots.linux.dev/logs/vmksft/mptcp-dbg/results/412720/1-mptcp-join-sh/stderr
Fixes: f8a1d9b ("mptcp: make fallback action and fallback decision atomic")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20251205-net-mptcp-misc-fixes-6-19-rc1-v1-4-9e4781a6c1b8@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
The IPv4 code path in __ip_vs_get_out_rt() calls dst_link_failure()
without ensuring skb->dev is set, leading to a NULL pointer dereference
in fib_compute_spec_dst() when ipv4_link_failure() attempts to send
ICMP destination unreachable messages.

The issue emerged after commit ed0de45 ("ipv4: recompile ip options
in ipv4_link_failure") started calling __ip_options_compile() from
ipv4_link_failure(). This code path eventually calls fib_compute_spec_dst()
which dereferences skb->dev. An attempt was made to fix the NULL skb->dev
dereference in commit 0113d9c ("ipv4: fix null-deref in
ipv4_link_failure"), but it only addressed the immediate dev_net(skb->dev)
dereference by using a fallback device. The fix was incomplete because
fib_compute_spec_dst() later in the call chain still accesses skb->dev
directly, which remains NULL when IPVS calls dst_link_failure().

The crash occurs when:
1. IPVS processes a packet in NAT mode with a misconfigured destination
2. Route lookup fails in __ip_vs_get_out_rt() before establishing a route
3. The error path calls dst_link_failure(skb) with skb->dev == NULL
4. ipv4_link_failure() → ipv4_send_dest_unreach() →
   __ip_options_compile() → fib_compute_spec_dst()
5. fib_compute_spec_dst() dereferences NULL skb->dev

Apply the same fix used for IPv6 in commit 326bf17 ("ipvs: fix
ipv6 route unreach panic"): set skb->dev from skb_dst(skb)->dev before
calling dst_link_failure().

KASAN: null-ptr-deref in range [0x0000000000000328-0x000000000000032f]
CPU: 1 PID: 12732 Comm: syz.1.3469 Not tainted 6.6.114 #2
RIP: 0010:__in_dev_get_rcu include/linux/inetdevice.h:233
RIP: 0010:fib_compute_spec_dst+0x17a/0x9f0 net/ipv4/fib_frontend.c:285
Call Trace:
  <TASK>
  spec_dst_fill net/ipv4/ip_options.c:232
  spec_dst_fill net/ipv4/ip_options.c:229
  __ip_options_compile+0x13a1/0x17d0 net/ipv4/ip_options.c:330
  ipv4_send_dest_unreach net/ipv4/route.c:1252
  ipv4_link_failure+0x702/0xb80 net/ipv4/route.c:1265
  dst_link_failure include/net/dst.h:437
  __ip_vs_get_out_rt+0x15fd/0x19e0 net/netfilter/ipvs/ip_vs_xmit.c:412
  ip_vs_nat_xmit+0x1d8/0xc80 net/netfilter/ipvs/ip_vs_xmit.c:764

Fixes: ed0de45 ("ipv4: recompile ip options in ipv4_link_failure")
Signed-off-by: Slavin Liu <slavin452@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Florian Westphal <fw@strlen.de>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
Fix a loop scenario of ethx:egress->ethx:egress

Example setup to reproduce:
tc qdisc add dev ethx root handle 1: drr
tc filter add dev ethx parent 1: protocol ip prio 1 matchall \
         action mirred egress redirect dev ethx

Now ping out of ethx and you get a deadlock:

[  116.892898][  T307] ============================================
[  116.893182][  T307] WARNING: possible recursive locking detected
[  116.893418][  T307] 6.18.0-rc6-01205-ge05021a829b8-dirty #204 Not tainted
[  116.893682][  T307] --------------------------------------------
[  116.893926][  T307] ping/307 is trying to acquire lock:
[  116.894133][  T307] ffff88800c122908 (&sch->root_lock_key){+...}-{3:3}, at: __dev_queue_xmit+0x2210/0x3b50
[  116.894517][  T307]
[  116.894517][  T307] but task is already holding lock:
[  116.894836][  T307] ffff88800c122908 (&sch->root_lock_key){+...}-{3:3}, at: __dev_queue_xmit+0x2210/0x3b50
[  116.895252][  T307]
[  116.895252][  T307] other info that might help us debug this:
[  116.895608][  T307]  Possible unsafe locking scenario:
[  116.895608][  T307]
[  116.895901][  T307]        CPU0
[  116.896057][  T307]        ----
[  116.896200][  T307]   lock(&sch->root_lock_key);
[  116.896392][  T307]   lock(&sch->root_lock_key);
[  116.896605][  T307]
[  116.896605][  T307]  *** DEADLOCK ***
[  116.896605][  T307]
[  116.896864][  T307]  May be due to missing lock nesting notation
[  116.896864][  T307]
[  116.897123][  T307] 6 locks held by ping/307:
[  116.897302][  T307]  #0: ffff88800b4b0250 (sk_lock-AF_INET){+.+.}-{0:0}, at: raw_sendmsg+0xb20/0x2cf0
[  116.897808][  T307]  #1: ffffffff88c839c0 (rcu_read_lock){....}-{1:3}, at: ip_output+0xa9/0x600
[  116.898138][  T307]  #2: ffffffff88c839c0 (rcu_read_lock){....}-{1:3}, at: ip_finish_output2+0x2c6/0x1ee0
[  116.898459][  T307]  #3: ffffffff88c83960 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x200/0x3b50
[  116.898782][  T307]  #4: ffff88800c122908 (&sch->root_lock_key){+...}-{3:3}, at: __dev_queue_xmit+0x2210/0x3b50
[  116.899132][  T307]  #5: ffffffff88c83960 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x200/0x3b50
[  116.899442][  T307]
[  116.899442][  T307] stack backtrace:
[  116.899667][  T307] CPU: 2 UID: 0 PID: 307 Comm: ping Not tainted 6.18.0-rc6-01205-ge05021a829b8-dirty #204 PREEMPT(voluntary)
[  116.899672][  T307] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  116.899675][  T307] Call Trace:
[  116.899678][  T307]  <TASK>
[  116.899680][  T307]  dump_stack_lvl+0x6f/0xb0
[  116.899688][  T307]  print_deadlock_bug.cold+0xc0/0xdc
[  116.899695][  T307]  __lock_acquire+0x11f7/0x1be0
[  116.899704][  T307]  lock_acquire+0x162/0x300
[  116.899707][  T307]  ? __dev_queue_xmit+0x2210/0x3b50
[  116.899713][  T307]  ? srso_alias_return_thunk+0x5/0xfbef5
[  116.899717][  T307]  ? stack_trace_save+0x93/0xd0
[  116.899723][  T307]  _raw_spin_lock+0x30/0x40
[  116.899728][  T307]  ? __dev_queue_xmit+0x2210/0x3b50
[  116.899731][  T307]  __dev_queue_xmit+0x2210/0x3b50

Fixes: 178ca30 ("Revert "net/sched: Fix mirred deadlock on device recursion"")
Tested-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20251210162255.1057663-1-jhs@mojatatu.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
A race condition was found in sg_proc_debug_helper(). It was observed on
a system using an IBM LTO-9 SAS Tape Drive (ULTRIUM-TD9) and monitoring
/proc/scsi/sg/debug every second. A very large elapsed time would
sometimes appear. This is caused by two race conditions.

We reproduced the issue with an IBM ULTRIUM-HH9 tape drive on an x86_64
architecture. A patched kernel was built, and the race condition could
not be observed anymore after the application of this patch. A
reproducer C program utilising the scsi_debug module was also built by
Changhui Zhong and can be viewed here:

https://github.com/MichaelRabek/linux-tests/blob/master/drivers/scsi/sg/sg_race_trigger.c

The first race happens between the reading of hp->duration in
sg_proc_debug_helper() and request completion in sg_rq_end_io().  The
hp->duration member variable may hold either of two types of
information:

 #1 - The start time of the request. This value is present while
      the request is not yet finished.

 #2 - The total execution time of the request (end_time - start_time).

If sg_proc_debug_helper() executes *after* the value of hp->duration was
changed from #1 to #2, but *before* srp->done is set to 1 in
sg_rq_end_io(), a fresh timestamp is taken in the else branch, and the
elapsed time (value type #2) is subtracted from a timestamp, which
cannot yield a valid elapsed time (which is a type #2 value as well).

To fix this issue, the value of hp->duration must change under the
protection of the sfp->rq_list_lock in sg_rq_end_io().  Since
sg_proc_debug_helper() takes this read lock, the change to srp->done and
srp->header.duration will happen atomically from the perspective of
sg_proc_debug_helper() and the race condition is thus eliminated.

The second race condition happens between sg_proc_debug_helper() and
sg_new_write(). Even though hp->duration is set to the current time
stamp in sg_add_request() under the write lock's protection, it gets
overwritten by a call to get_sg_io_hdr(), which calls copy_from_user()
to copy struct sg_io_hdr from userspace into kernel space. hp->duration
is set to the start time again in sg_common_write(). If
sg_proc_debug_helper() is called between these two calls, an arbitrary
value set by userspace (usually zero) is used to compute the elapsed
time.

To fix this issue, hp->duration must be set to the current timestamp
again after get_sg_io_hdr() returns successfully. A small race window
still exists between get_sg_io_hdr() and setting hp->duration, but this
window is only a few instructions wide and does not result in observable
issues in practice, as confirmed by testing.

Additionally, we fix the format specifier from %d to %u for printing
unsigned int values in sg_proc_debug_helper().

Signed-off-by: Michal Rábek <mrabek@redhat.com>
Suggested-by: Tomas Henzl <thenzl@redhat.com>
Tested-by: Changhui Zhong <czhong@redhat.com>
Reviewed-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: John Meneghini <jmeneghi@redhat.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Link: https://patch.msgid.link/20251212160900.64924-1-mrabek@redhat.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
When a page is freed it coalesces with a buddy into a higher order page
while possible.  When the buddy page migrate type differs, it is expected
to be updated to match the one of the page being freed.

However, only the first pageblock of the buddy page is updated, while the
rest of the pageblocks are left unchanged.

That causes warnings in later expand() and other code paths (like below),
since an inconsistency between migration type of the list containing the
page and the page-owned pageblocks migration types is introduced.

[  308.986589] ------------[ cut here ]------------
[  308.987227] page type is 0, passed migratetype is 1 (nr=256)
[  308.987275] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:812 expand+0x23c/0x270
[  308.987293] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.987439] Unloaded tainted modules: hmac_s390(E):2
[  308.987650] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G            E       6.18.0-gcc-bpf-debug #431 PREEMPT
[  308.987657] Tainted: [E]=UNSIGNED_MODULE
[  308.987661] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.987666] Krnl PSW : 0404f00180000000 00000349976fa600 (expand+0x240/0x270)
[  308.987676]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.987682] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.987688]            0000000000000005 0000034980000005 000002be803ac000 0000023efe6c8300
[  308.987692]            0000000000000008 0000034998d57290 000002be00000100 0000023e00000008
[  308.987696]            0000000000000000 0000000000000000 00000349976fa5fc 000002c99b1eb6f0
[  308.987708] Krnl Code: 00000349976fa5f0: c020008a02f2	larl	%r2,000003499883abd4
                          00000349976fa5f6: c0e5ffe3f4b5	brasl	%r14,0000034997378f60
                         #00000349976fa5fc: af000000		mc	0,0
                         >00000349976fa600: a7f4ff4c		brc	15,00000349976fa498
                          00000349976fa604: b9040026		lgr	%r2,%r6
                          00000349976fa608: c0300088317f	larl	%r3,0000034998800906
                          00000349976fa60e: c0e5fffdb6e1	brasl	%r14,00000349976b13d0
                          00000349976fa614: af000000		mc	0,0
[  308.987734] Call Trace:
[  308.987738]  [<00000349976fa600>] expand+0x240/0x270
[  308.987744] ([<00000349976fa5fc>] expand+0x23c/0x270)
[  308.987749]  [<00000349976ff95e>] rmqueue_bulk+0x71e/0x940
[  308.987754]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.987759]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.987763]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.987768]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.987774]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.987781]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.987786]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.987791]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.987799]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.987804]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.987809]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.987813]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.987822]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.987830]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.987838] 3 locks held by mempig_verify/5224:
[  308.987842]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.987859]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.987871]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.987886] Last Breaking-Event-Address:
[  308.987890]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.987897] irq event stamp: 52330356
[  308.987901] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.987907] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.987913] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.987922] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.987929] ---[ end trace 0000000000000000 ]---
[  308.987936] ------------[ cut here ]------------
[  308.987940] page type is 0, passed migratetype is 1 (nr=256)
[  308.987951] WARNING: CPU: 1 PID: 5224 at mm/page_alloc.c:860 __del_page_from_free_list+0x1be/0x1e0
[  308.987960] Modules linked in: algif_hash(E) af_alg(E) nft_fib_inet(E) nft_fib_ipv4(E) nft_fib_ipv6(E) nft_fib(E) nft_reject_inet(E) nf_reject_ipv4(E) nf_reject_ipv6(E) nft_reject(E) nft_ct(E) nft_chain_nat(E) nf_nat(E) nf_conntrack(E) nf_defrag_ipv6(E) nf_defrag_ipv4(E) nf_tables(E) s390_trng(E) vfio_ccw(E) mdev(E) vfio_iommu_type1(E) vfio(E) sch_fq_codel(E) drm(E) i2c_core(E) drm_panel_orientation_quirks(E) loop(E) nfnetlink(E) vsock_loopback(E) vmw_vsock_virtio_transport_common(E) vsock(E) ctcm(E) fsm(E) diag288_wdt(E) watchdog(E) zfcp(E) scsi_transport_fc(E) ghash_s390(E) prng(E) aes_s390(E) des_generic(E) des_s390(E) libdes(E) sha3_512_s390(E) sha3_256_s390(E) sha_common(E) paes_s390(E) crypto_engine(E) pkey_cca(E) pkey_ep11(E) zcrypt(E) rng_core(E) pkey_pckmo(E) pkey(E) autofs4(E)
[  308.988070] Unloaded tainted modules: hmac_s390(E):2
[  308.988087] CPU: 1 UID: 0 PID: 5224 Comm: mempig_verify Kdump: loaded Tainted: G        W   E       6.18.0-gcc-bpf-debug #431 PREEMPT
[  308.988095] Tainted: [W]=WARN, [E]=UNSIGNED_MODULE
[  308.988100] Hardware name: IBM 3906 M04 704 (z/VM 7.3.0)
[  308.988105] Krnl PSW : 0404f00180000000 00000349976f9e32 (__del_page_from_free_list+0x1c2/0x1e0)
[  308.988118]            R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:3 CC:3 PM:0 RI:0 EA:3
[  308.988127] Krnl GPRS: 0000034980000004 0000000000000005 0000000000000030 000003499a0e6d88
[  308.988133]            0000000000000005 0000034980000005 0000034998d57290 0000023efe6c8300
[  308.988139]            0000000000000001 0000000000000008 000002be00000100 000002be803ac000
[  308.988144]            0000000000000000 0000000000000001 00000349976f9e2e 000002c99b1eb728
[  308.988153] Krnl Code: 00000349976f9e22: c020008a06d9	larl	%r2,000003499883abd4
                          00000349976f9e28: c0e5ffe3f89c	brasl	%r14,0000034997378f60
                         #00000349976f9e2e: af000000		mc	0,0
                         >00000349976f9e32: a7f4ff4e		brc	15,00000349976f9cce
                          00000349976f9e36: b904002b		lgr	%r2,%r11
                          00000349976f9e3a: c030008a06e7	larl	%r3,000003499883ac08
                          00000349976f9e40: c0e5fffdbac8	brasl	%r14,00000349976b13d0
                          00000349976f9e46: af000000		mc	0,0
[  308.988184] Call Trace:
[  308.988188]  [<00000349976f9e32>] __del_page_from_free_list+0x1c2/0x1e0
[  308.988195] ([<00000349976f9e2e>] __del_page_from_free_list+0x1be/0x1e0)
[  308.988202]  [<00000349976ff946>] rmqueue_bulk+0x706/0x940
[  308.988208]  [<00000349976ffd7e>] __rmqueue_pcplist+0x1fe/0x2a0
[  308.988214]  [<0000034997700966>] rmqueue.isra.0+0xb46/0xf40
[  308.988221]  [<0000034997703ec8>] get_page_from_freelist+0x198/0x8d0
[  308.988227]  [<0000034997706fa8>] __alloc_frozen_pages_noprof+0x198/0x400
[  308.988233]  [<00000349977536f8>] alloc_pages_mpol+0xb8/0x220
[  308.988240]  [<0000034997753bf6>] folio_alloc_mpol_noprof+0x26/0xc0
[  308.988247]  [<0000034997753e4c>] vma_alloc_folio_noprof+0x6c/0xa0
[  308.988253]  [<0000034997775b22>] vma_alloc_anon_folio_pmd+0x42/0x240
[  308.988260]  [<000003499777bfea>] __do_huge_pmd_anonymous_page+0x3a/0x210
[  308.988267]  [<00000349976cb08e>] __handle_mm_fault+0x4de/0x500
[  308.988273]  [<00000349976cb14c>] handle_mm_fault+0x9c/0x3a0
[  308.988279]  [<000003499734d70e>] do_exception+0x1de/0x540
[  308.988286]  [<0000034998387390>] __do_pgm_check+0x130/0x220
[  308.988293]  [<000003499839a934>] pgm_check_handler+0x114/0x160
[  308.988300] 3 locks held by mempig_verify/5224:
[  308.988305]  #0: 0000023ea44c1e08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0xb2/0x2a0
[  308.988322]  #1: 0000023ee4d41b18 (&pcp->lock){+.+.}-{2:2}, at: rmqueue.isra.0+0xad6/0xf40
[  308.988334]  #2: 0000023efe6c8998 (&zone->lock){..-.}-{2:2}, at: rmqueue_bulk+0x5a/0x940
[  308.988346] Last Breaking-Event-Address:
[  308.988350]  [<0000034997379096>] __warn_printk+0x136/0x140
[  308.988356] irq event stamp: 52330356
[  308.988360] hardirqs last  enabled at (52330355): [<000003499838742e>] __do_pgm_check+0x1ce/0x220
[  308.988366] hardirqs last disabled at (52330356): [<000003499839932e>] _raw_spin_lock_irqsave+0x9e/0xe0
[  308.988373] softirqs last  enabled at (52329882): [<0000034997383786>] handle_softirqs+0x2c6/0x530
[  308.988380] softirqs last disabled at (52329859): [<0000034997382f86>] __irq_exit_rcu+0x126/0x140
[  308.988388] ---[ end trace 0000000000000000 ]---

Link: https://lkml.kernel.org/r/20251215081002.3353900A9c-agordeev@linux.ibm.com
Link: https://lkml.kernel.org/r/20251212151457.3898073Add-agordeev@linux.ibm.com
Fixes: e6cf9e1 ("mm: page_alloc: fix up block types when merging compatible blocks")
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Closes: https://lore.kernel.org/linux-mm/87wmalyktd.fsf@linux.ibm.com/
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Cc: Marc Hartmayer <mhartmay@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
When running the Rust maple tree kunit tests with lockdep, you may trigger
a warning that looks like this:

	lib/maple_tree.c:780 suspicious rcu_dereference_check() usage!

	other info that might help us debug this:

	rcu_scheduler_active = 2, debug_locks = 1
	no locks held by kunit_try_catch/344.

	stack backtrace:
	CPU: 3 UID: 0 PID: 344 Comm: kunit_try_catch Tainted: G                 N  6.19.0-rc1+ #2 NONE
	Tainted: [N]=TEST
	Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014
	Call Trace:
	 <TASK>
	 dump_stack_lvl+0x71/0x90
	 lockdep_rcu_suspicious+0x150/0x190
	 mas_start+0x104/0x150
	 mas_find+0x179/0x240
	 _RINvNtCs5QSdWC790r4_4core3ptr13drop_in_placeINtNtCs1cdwasc6FUb_6kernel10maple_tree9MapleTreeINtNtNtBL_5alloc4kbox3BoxlNtNtB1x_9allocator7KmallocEEECsgxAQYCfdR72_25doctests_kernel_generated+0xaf/0x130
	 rust_doctest_kernel_maple_tree_rs_0+0x600/0x6b0
	 ? lock_release+0xeb/0x2a0
	 ? kunit_try_catch_run+0x210/0x210
	 kunit_try_run_case+0x74/0x160
	 ? kunit_try_catch_run+0x210/0x210
	 kunit_generic_run_threadfn_adapter+0x12/0x30
	 kthread+0x21c/0x230
	 ? __do_trace_sched_kthread_stop_ret+0x40/0x40
	 ret_from_fork+0x16c/0x270
	 ? __do_trace_sched_kthread_stop_ret+0x40/0x40
	 ret_from_fork_asm+0x11/0x20
	 </TASK>

This is because the destructor of maple tree calls mas_find() without
taking rcu_read_lock() or the spinlock.  Doing that is actually ok in this
case since the destructor has exclusive access to the entire maple tree,
but it triggers a lockdep warning.  To fix that, take the rcu read lock.

In the future, it's possible that memory reclaim could gain a feature
where it reallocates entries in maple trees even if no user-code is
touching it.  If that feature is added, then this use of rcu read lock
would become load-bearing, so I did not make it conditional on lockdep.

We have to repeatedly take and release rcu because the destructor of T
might perform operations that sleep.

Link: https://lkml.kernel.org/r/20251217-maple-drop-rcu-v1-1-702af063573f@google.com
Fixes: da939ef ("rust: maple_tree: add MapleTree")
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reported-by: Andreas Hindborg <a.hindborg@kernel.org>
Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/x/topic/x/near/564215108
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Cc: Andrew Ballance <andrewjballance@gmail.com>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Danilo Krummrich <dakr@kernel.org>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Trevor Gross <tmgross@umich.edu>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
… to macb_open()

In the non-RT kernel, local_bh_disable() merely disables preemption,
whereas it maps to an actual spin lock in the RT kernel. Consequently,
when attempting to refill RX buffers via netdev_alloc_skb() in
macb_mac_link_up(), a deadlock scenario arises as follows:

   WARNING: possible circular locking dependency detected
   6.18.0-08691-g2061f18ad76e #39 Not tainted
   ------------------------------------------------------
   kworker/0:0/8 is trying to acquire lock:
   ffff00080369bbe0 (&bp->lock){+.+.}-{3:3}, at: macb_start_xmit+0x808/0xb7c

   but task is already holding lock:
   ffff000803698e58 (&queue->tx_ptr_lock){+...}-{3:3}, at: macb_start_xmit
   +0x148/0xb7c

   which lock already depends on the new lock.

   the existing dependency chain (in reverse order) is:

   -> #3 (&queue->tx_ptr_lock){+...}-{3:3}:
          rt_spin_lock+0x50/0x1f0
          macb_start_xmit+0x148/0xb7c
          dev_hard_start_xmit+0x94/0x284
          sch_direct_xmit+0x8c/0x37c
          __dev_queue_xmit+0x708/0x1120
          neigh_resolve_output+0x148/0x28c
          ip6_finish_output2+0x2c0/0xb2c
          __ip6_finish_output+0x114/0x308
          ip6_output+0xc4/0x4a4
          mld_sendpack+0x220/0x68c
          mld_ifc_work+0x2a8/0x4f4
          process_one_work+0x20c/0x5f8
          worker_thread+0x1b0/0x35c
          kthread+0x144/0x200
          ret_from_fork+0x10/0x20

   -> #2 (_xmit_ETHER#2){+...}-{3:3}:
          rt_spin_lock+0x50/0x1f0
          sch_direct_xmit+0x11c/0x37c
          __dev_queue_xmit+0x708/0x1120
          neigh_resolve_output+0x148/0x28c
          ip6_finish_output2+0x2c0/0xb2c
          __ip6_finish_output+0x114/0x308
          ip6_output+0xc4/0x4a4
          mld_sendpack+0x220/0x68c
          mld_ifc_work+0x2a8/0x4f4
          process_one_work+0x20c/0x5f8
          worker_thread+0x1b0/0x35c
          kthread+0x144/0x200
          ret_from_fork+0x10/0x20

   -> #1 ((softirq_ctrl.lock)){+.+.}-{3:3}:
          lock_release+0x250/0x348
          __local_bh_enable_ip+0x7c/0x240
          __netdev_alloc_skb+0x1b4/0x1d8
          gem_rx_refill+0xdc/0x240
          gem_init_rings+0xb4/0x108
          macb_mac_link_up+0x9c/0x2b4
          phylink_resolve+0x170/0x614
          process_one_work+0x20c/0x5f8
          worker_thread+0x1b0/0x35c
          kthread+0x144/0x200
          ret_from_fork+0x10/0x20

   -> #0 (&bp->lock){+.+.}-{3:3}:
          __lock_acquire+0x15a8/0x2084
          lock_acquire+0x1cc/0x350
          rt_spin_lock+0x50/0x1f0
          macb_start_xmit+0x808/0xb7c
          dev_hard_start_xmit+0x94/0x284
          sch_direct_xmit+0x8c/0x37c
          __dev_queue_xmit+0x708/0x1120
          neigh_resolve_output+0x148/0x28c
          ip6_finish_output2+0x2c0/0xb2c
          __ip6_finish_output+0x114/0x308
          ip6_output+0xc4/0x4a4
          mld_sendpack+0x220/0x68c
          mld_ifc_work+0x2a8/0x4f4
          process_one_work+0x20c/0x5f8
          worker_thread+0x1b0/0x35c
          kthread+0x144/0x200
          ret_from_fork+0x10/0x20

   other info that might help us debug this:

   Chain exists of:
     &bp->lock --> _xmit_ETHER#2 --> &queue->tx_ptr_lock

    Possible unsafe locking scenario:

          CPU0                    CPU1
          ----                    ----
     lock(&queue->tx_ptr_lock);
                                  lock(_xmit_ETHER#2);
                                  lock(&queue->tx_ptr_lock);
     lock(&bp->lock);

    *** DEADLOCK ***

   Call trace:
    show_stack+0x18/0x24 (C)
    dump_stack_lvl+0xa0/0xf0
    dump_stack+0x18/0x24
    print_circular_bug+0x28c/0x370
    check_noncircular+0x198/0x1ac
    __lock_acquire+0x15a8/0x2084
    lock_acquire+0x1cc/0x350
    rt_spin_lock+0x50/0x1f0
    macb_start_xmit+0x808/0xb7c
    dev_hard_start_xmit+0x94/0x284
    sch_direct_xmit+0x8c/0x37c
    __dev_queue_xmit+0x708/0x1120
    neigh_resolve_output+0x148/0x28c
    ip6_finish_output2+0x2c0/0xb2c
    __ip6_finish_output+0x114/0x308
    ip6_output+0xc4/0x4a4
    mld_sendpack+0x220/0x68c
    mld_ifc_work+0x2a8/0x4f4
    process_one_work+0x20c/0x5f8
    worker_thread+0x1b0/0x35c
    kthread+0x144/0x200
    ret_from_fork+0x10/0x20

Notably, invoking the mog_init_rings() callback upon link establishment
is unnecessary. Instead, we can exclusively call mog_init_rings() within
the ndo_open() callback. This adjustment resolves the deadlock issue.
Furthermore, since MACB_CAPS_MACB_IS_EMAC cases do not use mog_init_rings()
when opening the network interface via at91ether_open(), moving
mog_init_rings() to macb_open() also eliminates the MACB_CAPS_MACB_IS_EMAC
check.

Fixes: 633e98a ("net: macb: use resolved link config in mac_link_up()")
Cc: stable@vger.kernel.org
Suggested-by: Kevin Hao <kexin.hao@windriver.com>
Signed-off-by: Xiaolei Wang <xiaolei.wang@windriver.com>
Link: https://patch.msgid.link/20251222015624.1994551-1-xiaolei.wang@windriver.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
ctx->tcxt_list holds the tasks using this ring, and it's currently
protected by the normal ctx->uring_lock. However, this can cause a
circular locking issue, as reported by syzbot, where cancelations off
exec end up needing to remove an entry from this list:

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L
------------------------------------------------------
syz.0.9999/12287 is trying to acquire lock:
ffff88805851c0a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179

but task is already holding lock:
ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: prepare_bprm_creds fs/exec.c:1360 [inline]
ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xb9/0x1400 fs/exec.c:1733

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&sig->cred_guard_mutex){+.+.}-{4:4}:
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
       proc_pid_attr_write+0x547/0x630 fs/proc/base.c:2837
       vfs_write+0x27e/0xb30 fs/read_write.c:684
       ksys_write+0x145/0x250 fs/read_write.c:738
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (sb_writers#3){.+.+}-{0:0}:
       percpu_down_read_internal include/linux/percpu-rwsem.h:53 [inline]
       percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
       __sb_start_write include/linux/fs/super.h:19 [inline]
       sb_start_write+0x4d/0x1c0 include/linux/fs/super.h:125
       mnt_want_write+0x41/0x90 fs/namespace.c:499
       open_last_lookups fs/namei.c:4529 [inline]
       path_openat+0xadd/0x3dd0 fs/namei.c:4784
       do_filp_open+0x1fa/0x410 fs/namei.c:4814
       io_openat2+0x3e0/0x5c0 io_uring/openclose.c:143
       __io_issue_sqe+0x181/0x4b0 io_uring/io_uring.c:1792
       io_issue_sqe+0x165/0x1060 io_uring/io_uring.c:1815
       io_queue_sqe io_uring/io_uring.c:2042 [inline]
       io_submit_sqe io_uring/io_uring.c:2320 [inline]
       io_submit_sqes+0xbf4/0x2140 io_uring/io_uring.c:2434
       __do_sys_io_uring_enter io_uring/io_uring.c:3280 [inline]
       __se_sys_io_uring_enter+0x2e0/0x2b60 io_uring/io_uring.c:3219
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&ctx->uring_lock){+.+.}-{4:4}:
       check_prev_add kernel/locking/lockdep.c:3165 [inline]
       check_prevs_add kernel/locking/lockdep.c:3284 [inline]
       validate_chain kernel/locking/lockdep.c:3908 [inline]
       __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
       lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
       __mutex_lock_common kernel/locking/mutex.c:614 [inline]
       __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
       io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
       io_uring_clean_tctx+0xd4/0x1a0 io_uring/tctx.c:195
       io_uring_cancel_generic+0x6ca/0x7d0 io_uring/cancel.c:646
       io_uring_task_cancel include/linux/io_uring.h:24 [inline]
       begin_new_exec+0x10ed/0x2440 fs/exec.c:1131
       load_elf_binary+0x9f8/0x2d70 fs/binfmt_elf.c:1010
       search_binary_handler fs/exec.c:1669 [inline]
       exec_binprm fs/exec.c:1701 [inline]
       bprm_execve+0x92e/0x1400 fs/exec.c:1753
       do_execveat_common+0x510/0x6a0 fs/exec.c:1859
       do_execve fs/exec.c:1933 [inline]
       __do_sys_execve fs/exec.c:2009 [inline]
       __se_sys_execve fs/exec.c:2004 [inline]
       __x64_sys_execve+0x94/0xb0 fs/exec.c:2004
       do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
       do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &ctx->uring_lock --> sb_writers#3 --> &sig->cred_guard_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sig->cred_guard_mutex);
                               lock(sb_writers#3);
                               lock(&sig->cred_guard_mutex);
  lock(&ctx->uring_lock);

 *** DEADLOCK ***

1 lock held by syz.0.9999/12287:
 #0: ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: prepare_bprm_creds fs/exec.c:1360 [inline]
 #0: ffff88802db5a2e0 (&sig->cred_guard_mutex){+.+.}-{4:4}, at: bprm_execve+0xb9/0x1400 fs/exec.c:1733

stack backtrace:
CPU: 0 UID: 0 PID: 12287 Comm: syz.0.9999 Tainted: G             L      syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_circular_bug+0x2e2/0x300 kernel/locking/lockdep.c:2043
 check_noncircular+0x12e/0x150 kernel/locking/lockdep.c:2175
 check_prev_add kernel/locking/lockdep.c:3165 [inline]
 check_prevs_add kernel/locking/lockdep.c:3284 [inline]
 validate_chain kernel/locking/lockdep.c:3908 [inline]
 __lock_acquire+0x15a6/0x2cf0 kernel/locking/lockdep.c:5237
 lock_acquire+0x107/0x340 kernel/locking/lockdep.c:5868
 __mutex_lock_common kernel/locking/mutex.c:614 [inline]
 __mutex_lock+0x187/0x1350 kernel/locking/mutex.c:776
 io_uring_del_tctx_node+0xf0/0x2c0 io_uring/tctx.c:179
 io_uring_clean_tctx+0xd4/0x1a0 io_uring/tctx.c:195
 io_uring_cancel_generic+0x6ca/0x7d0 io_uring/cancel.c:646
 io_uring_task_cancel include/linux/io_uring.h:24 [inline]
 begin_new_exec+0x10ed/0x2440 fs/exec.c:1131
 load_elf_binary+0x9f8/0x2d70 fs/binfmt_elf.c:1010
 search_binary_handler fs/exec.c:1669 [inline]
 exec_binprm fs/exec.c:1701 [inline]
 bprm_execve+0x92e/0x1400 fs/exec.c:1753
 do_execveat_common+0x510/0x6a0 fs/exec.c:1859
 do_execve fs/exec.c:1933 [inline]
 __do_sys_execve fs/exec.c:2009 [inline]
 __se_sys_execve fs/exec.c:2004 [inline]
 __x64_sys_execve+0x94/0xb0 fs/exec.c:2004
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff3a8b8f749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff3a9a97038 EFLAGS: 00000246 ORIG_RAX: 000000000000003b
RAX: ffffffffffffffda RBX: 00007ff3a8de5fa0 RCX: 00007ff3a8b8f749
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000400
RBP: 00007ff3a8c13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff3a8de6038 R14: 00007ff3a8de5fa0 R15: 00007ff3a8f0fa28
 </TASK>

Add a separate lock just for the tctx_list, tctx_lock. This can nest
under ->uring_lock, where necessary, and be used separately for list
manipulation. For the cancelation off exec side, this removes the
need to grab ->uring_lock, hence fixing the circular locking
dependency.

Reported-by: syzbot+b0e3b77ffaa8a4067ce5@syzkaller.appspotmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
After rename exchanging (either with the rename exchange operation or
regular renames in multiple non-atomic steps) two inodes and at least
one of them is a directory, we can end up with a log tree that contains
only of the inodes and after a power failure that can result in an attempt
to delete the other inode when it should not because it was not deleted
before the power failure. In some case that delete attempt fails when
the target inode is a directory that contains a subvolume inside it, since
the log replay code is not prepared to deal with directory entries that
point to root items (only inode items).

1) We have directories "dir1" (inode A) and "dir2" (inode B) under the
   same parent directory;

2) We have a file (inode C) under directory "dir1" (inode A);

3) We have a subvolume inside directory "dir2" (inode B);

4) All these inodes were persisted in a past transaction and we are
   currently at transaction N;

5) We rename the file (inode C), so at btrfs_log_new_name() we update
   inode C's last_unlink_trans to N;

6) We get a rename exchange for "dir1" (inode A) and "dir2" (inode B),
   so after the exchange "dir1" is inode B and "dir2" is inode A.
   During the rename exchange we call btrfs_log_new_name() for inodes
   A and B, but because they are directories, we don't update their
   last_unlink_trans to N;

7) An fsync against the file (inode C) is done, and because its inode
   has a last_unlink_trans with a value of N we log its parent directory
   (inode A) (through btrfs_log_all_parents(), called from
   btrfs_log_inode_parent()).

8) So we end up with inode B not logged, which now has the old name
   of inode A. At copy_inode_items_to_log(), when logging inode A, we
   did not check if we had any conflicting inode to log because inode
   A has a generation lower than the current transaction (created in
   a past transaction);

9) After a power failure, when replaying the log tree, since we find that
   inode A has a new name that conflicts with the name of inode B in the
   fs tree, we attempt to delete inode B... this is wrong since that
   directory was never deleted before the power failure, and because there
   is a subvolume inside that directory, attempting to delete it will fail
   since replay_dir_deletes() and btrfs_unlink_inode() are not prepared
   to deal with dir items that point to roots instead of inodes.

   When that happens the mount fails and we get a stack trace like the
   following:

   [87.2314] BTRFS info (device dm-0): start tree-log replay
   [87.2318] BTRFS critical (device dm-0): failed to delete reference to subvol, root 5 inode 256 parent 259
   [87.2332] ------------[ cut here ]------------
   [87.2338] BTRFS: Transaction aborted (error -2)
   [87.2346] WARNING: CPU: 1 PID: 638968 at fs/btrfs/inode.c:4345 __btrfs_unlink_inode+0x416/0x440 [btrfs]
   [87.2368] Modules linked in: btrfs loop dm_thin_pool (...)
   [87.2470] CPU: 1 UID: 0 PID: 638968 Comm: mount Tainted: G        W           6.18.0-rc7-btrfs-next-218+ #2 PREEMPT(full)
   [87.2489] Tainted: [W]=WARN
   [87.2494] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
   [87.2514] RIP: 0010:__btrfs_unlink_inode+0x416/0x440 [btrfs]
   [87.2538] Code: c0 89 04 24 (...)
   [87.2568] RSP: 0018:ffffc0e741f4b9b8 EFLAGS: 00010286
   [87.2574] RAX: 0000000000000000 RBX: ffff9d3ec8a6cf60 RCX: 0000000000000000
   [87.2582] RDX: 0000000000000002 RSI: ffffffff84ab45a1 RDI: 00000000ffffffff
   [87.2591] RBP: ffff9d3ec8a6ef20 R08: 0000000000000000 R09: ffffc0e741f4b840
   [87.2599] R10: ffff9d45dc1fffa8 R11: 0000000000000003 R12: ffff9d3ee26d77e0
   [87.2608] R13: ffffc0e741f4ba98 R14: ffff9d4458040800 R15: ffff9d44b6b7ca10
   [87.2618] FS:  00007f7b9603a840(0000) GS:ffff9d4658982000(0000) knlGS:0000000000000000
   [87.2629] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
   [87.2637] CR2: 00007ffc9ec33b98 CR3: 000000011273e003 CR4: 0000000000370ef0
   [87.2648] Call Trace:
   [87.2651]  <TASK>
   [87.2654]  btrfs_unlink_inode+0x15/0x40 [btrfs]
   [87.2661]  unlink_inode_for_log_replay+0x27/0xf0 [btrfs]
   [87.2669]  check_item_in_log+0x1ea/0x2c0 [btrfs]
   [87.2676]  replay_dir_deletes+0x16b/0x380 [btrfs]
   [87.2684]  fixup_inode_link_count+0x34b/0x370 [btrfs]
   [87.2696]  fixup_inode_link_counts+0x41/0x160 [btrfs]
   [87.2703]  btrfs_recover_log_trees+0x1ff/0x7c0 [btrfs]
   [87.2711]  ? __pfx_replay_one_buffer+0x10/0x10 [btrfs]
   [87.2719]  open_ctree+0x10bb/0x15f0 [btrfs]
   [87.2726]  btrfs_get_tree.cold+0xb/0x16c [btrfs]
   [87.2734]  ? fscontext_read+0x15c/0x180
   [87.2740]  ? rw_verify_area+0x50/0x180
   [87.2746]  vfs_get_tree+0x25/0xd0
   [87.2750]  vfs_cmd_create+0x59/0xe0
   [87.2755]  __do_sys_fsconfig+0x4f6/0x6b0
   [87.2760]  do_syscall_64+0x50/0x1220
   [87.2764]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [87.2770] RIP: 0033:0x7f7b9625f4aa
   [87.2775] Code: 73 01 c3 48 (...)
   [87.2803] RSP: 002b:00007ffc9ec35b08 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
   [87.2817] RAX: ffffffffffffffda RBX: 0000558bfa91ac20 RCX: 00007f7b9625f4aa
   [87.2829] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
   [87.2842] RBP: 0000558bfa91b120 R08: 0000000000000000 R09: 0000000000000000
   [87.2854] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
   [87.2864] R13: 00007f7b963f1580 R14: 00007f7b963f326c R15: 00007f7b963d8a23
   [87.2877]  </TASK>
   [87.2882] ---[ end trace 0000000000000000 ]---
   [87.2891] BTRFS: error (device dm-0 state A) in __btrfs_unlink_inode:4345: errno=-2 No such entry
   [87.2904] BTRFS: error (device dm-0 state EAO) in do_abort_log_replay:191: errno=-2 No such entry
   [87.2915] BTRFS critical (device dm-0 state EAO): log tree (for root 5) leaf currently being processed (slot 7 key (258 12 257)):
   [87.2929] BTRFS info (device dm-0 state EAO): leaf 30736384 gen 10 total ptrs 7 free space 15712 owner 18446744073709551610
   [87.2929] BTRFS info (device dm-0 state EAO): refs 3 lock_owner 0 current 638968
   [87.2929]      item 0 key (257 INODE_ITEM 0) itemoff 16123 itemsize 160
   [87.2929]              inode generation 9 transid 10 size 0 nbytes 0
   [87.2929]              block group 0 mode 40755 links 1 uid 0 gid 0
   [87.2929]              rdev 0 sequence 7 flags 0x0
   [87.2929]              atime 1765464494.678070921
   [87.2929]              ctime 1765464494.686606513
   [87.2929]              mtime 1765464494.686606513
   [87.2929]              otime 1765464494.678070921
   [87.2929]      item 1 key (257 INODE_REF 256) itemoff 16109 itemsize 14
   [87.2929]              index 4 name_len 4
   [87.2929]      item 2 key (257 DIR_LOG_INDEX 2) itemoff 16101 itemsize 8
   [87.2929]              dir log end 2
   [87.2929]      item 3 key (257 DIR_LOG_INDEX 3) itemoff 16093 itemsize 8
   [87.2929]              dir log end 18446744073709551615
   [87.2930]      item 4 key (257 DIR_INDEX 3) itemoff 16060 itemsize 33
   [87.2930]              location key (258 1 0) type 1
   [87.2930]              transid 10 data_len 0 name_len 3
   [87.2930]      item 5 key (258 INODE_ITEM 0) itemoff 15900 itemsize 160
   [87.2930]              inode generation 9 transid 10 size 0 nbytes 0
   [87.2930]              block group 0 mode 100644 links 1 uid 0 gid 0
   [87.2930]              rdev 0 sequence 2 flags 0x0
   [87.2930]              atime 1765464494.678456467
   [87.2930]              ctime 1765464494.686606513
   [87.2930]              mtime 1765464494.678456467
   [87.2930]              otime 1765464494.678456467
   [87.2930]      item 6 key (258 INODE_REF 257) itemoff 15887 itemsize 13
   [87.2930]              index 3 name_len 3
   [87.2930] BTRFS critical (device dm-0 state EAO): log replay failed in unlink_inode_for_log_replay:1045 for root 5, stage 3, with error -2: failed to unlink inode 256 parent dir 259 name subvol root 5
   [87.2963] BTRFS: error (device dm-0 state EAO) in btrfs_recover_log_trees:7743: errno=-2 No such entry
   [87.2981] BTRFS: error (device dm-0 state EAO) in btrfs_replay_log:2083: errno=-2 No such entry (Failed to recover log tr

So fix this by changing copy_inode_items_to_log() to always detect if
there are conflicting inodes for the ref/extref of the inode being logged
even if the inode was created in a past transaction.

A test case for fstests will follow soon.

CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
…te in qfq_reset

`qfq_class->leaf_qdisc->q.qlen > 0` does not imply that the class
itself is active.

Two qfq_class objects may point to the same leaf_qdisc. This happens
when:

1. one QFQ qdisc is attached to the dev as the root qdisc, and

2. another QFQ qdisc is temporarily referenced (e.g., via qdisc_get()
/ qdisc_put()) and is pending to be destroyed, as in function
tc_new_tfilter.

When packets are enqueued through the root QFQ qdisc, the shared
leaf_qdisc->q.qlen increases. At the same time, the second QFQ
qdisc triggers qdisc_put and qdisc_destroy: the qdisc enters
qfq_reset() with its own q->q.qlen == 0, but its class's leaf
qdisc->q.qlen > 0. Therefore, the qfq_reset would wrongly deactivate
an inactive aggregate and trigger a null-deref in qfq_deactivate_agg:

[    0.903172] BUG: kernel NULL pointer dereference, address: 0000000000000000
[    0.903571] #PF: supervisor write access in kernel mode
[    0.903860] #PF: error_code(0x0002) - not-present page
[    0.904177] PGD 10299b067 P4D 10299b067 PUD 10299c067 PMD 0
[    0.904502] Oops: Oops: 0002 [#1] SMP NOPTI
[    0.904737] CPU: 0 UID: 0 PID: 135 Comm: exploit Not tainted 6.19.0-rc3+ #2 NONE
[    0.905157] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.17.0-0-gb52ca86e094d-prebuilt.qemu.org 04/01/2014
[    0.905754] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2))
[    0.906046] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0

Code starting with the faulting instruction
===========================================
   0:	0f 84 4d 01 00 00    	je     0x153
   6:	48 89 70 18          	mov    %rsi,0x18(%rax)
   a:	8b 4b 10             	mov    0x10(%rbx),%ecx
   d:	48 c7 c2 ff ff ff ff 	mov    $0xffffffffffffffff,%rdx
  14:	48 8b 78 08          	mov    0x8(%rax),%rdi
  18:	48 d3 e2             	shl    %cl,%rdx
  1b:	48 21 f2             	and    %rsi,%rdx
  1e:	48 2b 13             	sub    (%rbx),%rdx
  21:	48 8b 30             	mov    (%rax),%rsi
  24:	48 d3 ea             	shr    %cl,%rdx
  27:	8b 4b 18             	mov    0x18(%rbx),%ecx
	...
[    0.907095] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246
[    0.907368] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000
[    0.907723] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    0.908100] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000
[    0.908451] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000
[    0.908804] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880
[    0.909179] FS:  000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000
[    0.909572] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.909857] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0
[    0.910247] PKRU: 55555554
[    0.910391] Call Trace:
[    0.910527]  <TASK>
[    0.910638]  qfq_reset_qdisc (net/sched/sch_qfq.c:357 net/sched/sch_qfq.c:1485)
[    0.910826]  qdisc_reset (include/linux/skbuff.h:2195 include/linux/skbuff.h:2501 include/linux/skbuff.h:3424 include/linux/skbuff.h:3430 net/sched/sch_generic.c:1036)
[    0.911040]  __qdisc_destroy (net/sched/sch_generic.c:1076)
[    0.911236]  tc_new_tfilter (net/sched/cls_api.c:2447)
[    0.911447]  rtnetlink_rcv_msg (net/core/rtnetlink.c:6958)
[    0.911663]  ? __pfx_rtnetlink_rcv_msg (net/core/rtnetlink.c:6861)
[    0.911894]  netlink_rcv_skb (net/netlink/af_netlink.c:2550)
[    0.912100]  netlink_unicast (net/netlink/af_netlink.c:1319 net/netlink/af_netlink.c:1344)
[    0.912296]  ? __alloc_skb (net/core/skbuff.c:706)
[    0.912484]  netlink_sendmsg (net/netlink/af_netlink.c:1894)
[    0.912682]  sock_write_iter (net/socket.c:727 (discriminator 1) net/socket.c:742 (discriminator 1) net/socket.c:1195 (discriminator 1))
[    0.912880]  vfs_write (fs/read_write.c:593 fs/read_write.c:686)
[    0.913077]  ksys_write (fs/read_write.c:738)
[    0.913252]  do_syscall_64 (arch/x86/entry/syscall_64.c:63 (discriminator 1) arch/x86/entry/syscall_64.c:94 (discriminator 1))
[    0.913438]  entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:131)
[    0.913687] RIP: 0033:0x424c34
[    0.913844] Code: 89 02 48 c7 c0 ff ff ff ff eb bd 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 80 3d 2d 44 09 00 00 74 13 b8 01 00 00 00 0f 05 9

Code starting with the faulting instruction
===========================================
   0:	89 02                	mov    %eax,(%rdx)
   2:	48 c7 c0 ff ff ff ff 	mov    $0xffffffffffffffff,%rax
   9:	eb bd                	jmp    0xffffffffffffffc8
   b:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  12:	00 00 00
  15:	90                   	nop
  16:	f3 0f 1e fa          	endbr64
  1a:	80 3d 2d 44 09 00 00 	cmpb   $0x0,0x9442d(%rip)        # 0x9444e
  21:	74 13                	je     0x36
  23:	b8 01 00 00 00       	mov    $0x1,%eax
  28:	0f 05                	syscall
  2a:	09                   	.byte 0x9
[    0.914807] RSP: 002b:00007ffea1938b78 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[    0.915197] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 0000000000424c34
[    0.915556] RDX: 000000000000003c RSI: 000000002af378c0 RDI: 0000000000000003
[    0.915912] RBP: 00007ffea1938bc0 R08: 00000000004b8820 R09: 0000000000000000
[    0.916297] R10: 0000000000000001 R11: 0000000000000202 R12: 00007ffea1938d28
[    0.916652] R13: 00007ffea1938d38 R14: 00000000004b3828 R15: 0000000000000001
[    0.917039]  </TASK>
[    0.917158] Modules linked in:
[    0.917316] CR2: 0000000000000000
[    0.917484] ---[ end trace 0000000000000000 ]---
[    0.917717] RIP: 0010:qfq_deactivate_agg (include/linux/list.h:992 (discriminator 2) include/linux/list.h:1006 (discriminator 2) net/sched/sch_qfq.c:1367 (discriminator 2) net/sched/sch_qfq.c:1393 (discriminator 2))
[    0.917978] Code: 0f 84 4d 01 00 00 48 89 70 18 8b 4b 10 48 c7 c2 ff ff ff ff 48 8b 78 08 48 d3 e2 48 21 f2 48 2b 13 48 8b 30 48 d3 ea 8b 4b 18 0

Code starting with the faulting instruction
===========================================
   0:	0f 84 4d 01 00 00    	je     0x153
   6:	48 89 70 18          	mov    %rsi,0x18(%rax)
   a:	8b 4b 10             	mov    0x10(%rbx),%ecx
   d:	48 c7 c2 ff ff ff ff 	mov    $0xffffffffffffffff,%rdx
  14:	48 8b 78 08          	mov    0x8(%rax),%rdi
  18:	48 d3 e2             	shl    %cl,%rdx
  1b:	48 21 f2             	and    %rsi,%rdx
  1e:	48 2b 13             	sub    (%rbx),%rdx
  21:	48 8b 30             	mov    (%rax),%rsi
  24:	48 d3 ea             	shr    %cl,%rdx
  27:	8b 4b 18             	mov    0x18(%rbx),%ecx
	...
[    0.918902] RSP: 0018:ffffc900004a39a0 EFLAGS: 00010246
[    0.919198] RAX: ffff8881043a0880 RBX: ffff888102953340 RCX: 0000000000000000
[    0.919559] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    0.919908] RBP: ffff888102952180 R08: 0000000000000000 R09: 0000000000000000
[    0.920289] R10: ffff8881043a0000 R11: 0000000000000000 R12: ffff888102952000
[    0.920648] R13: ffff888102952180 R14: ffff8881043a0ad8 R15: ffff8881043a0880
[    0.921014] FS:  000000002a1a0380(0000) GS:ffff888196d8d000(0000) knlGS:0000000000000000
[    0.921424] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.921710] CR2: 0000000000000000 CR3: 0000000102993002 CR4: 0000000000772ef0
[    0.922097] PKRU: 55555554
[    0.922240] Kernel panic - not syncing: Fatal exception
[    0.922590] Kernel Offset: disabled

Fixes: 0545a30 ("pkt_sched: QFQ - quick fair queue scheduler")
Signed-off-by: Xiang Mei <xmei5@asu.edu>
Link: https://patch.msgid.link/20260106034100.1780779-1-xmei5@asu.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
The GPIO controller is configured as non-sleeping but it uses generic
pinctrl helpers which use a mutex for synchronization.

This can cause the following lockdep splat with shared GPIOs enabled on
boards which have multiple devices using the same GPIO:

BUG: sleeping function called from invalid context at
kernel/locking/mutex.c:591
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 12, name:
kworker/u16:0
preempt_count: 1, expected: 0
RCU nest depth: 0, expected: 0
6 locks held by kworker/u16:0/12:
  #0: ffff0001f0018d48 ((wq_completion)events_unbound#2){+.+.}-{0:0},
at: process_one_work+0x18c/0x604
  #1: ffff8000842dbdf0 (deferred_probe_work){+.+.}-{0:0}, at:
process_one_work+0x1b4/0x604
  #2: ffff0001f18498f8 (&dev->mutex){....}-{4:4}, at:
__device_attach+0x38/0x1b0
  #3: ffff0001f75f1e90 (&gdev->srcu){.+.?}-{0:0}, at:
gpiod_direction_output_raw_commit+0x0/0x360
  #4: ffff0001f46e3db8 (&shared_desc->spinlock){....}-{3:3}, at:
gpio_shared_proxy_direction_output+0xd0/0x144 [gpio_shared_proxy]
  #5: ffff0001f180ee90 (&gdev->srcu){.+.?}-{0:0}, at:
gpiod_direction_output_raw_commit+0x0/0x360
irq event stamp: 81450
hardirqs last  enabled at (81449): [<ffff8000813acba4>]
_raw_spin_unlock_irqrestore+0x74/0x78
hardirqs last disabled at (81450): [<ffff8000813abfb8>]
_raw_spin_lock_irqsave+0x84/0x88
softirqs last  enabled at (79616): [<ffff8000811455fc>]
__alloc_skb+0x17c/0x1e8
softirqs last disabled at (79614): [<ffff8000811455fc>]
__alloc_skb+0x17c/0x1e8
CPU: 2 UID: 0 PID: 12 Comm: kworker/u16:0 Not tainted
6.19.0-rc4-next-20260105+ #11975 PREEMPT
Hardware name: Hardkernel ODROID-M1 (DT)
Workqueue: events_unbound deferred_probe_work_func
Call trace:
  show_stack+0x18/0x24 (C)
  dump_stack_lvl+0x90/0xd0
  dump_stack+0x18/0x24
  __might_resched+0x144/0x248
  __might_sleep+0x48/0x98
  __mutex_lock+0x5c/0x894
  mutex_lock_nested+0x24/0x30
  pinctrl_get_device_gpio_range+0x44/0x128
  pinctrl_gpio_direction+0x3c/0xe0
  pinctrl_gpio_direction_output+0x14/0x20
  rockchip_gpio_direction_output+0xb8/0x19c
  gpiochip_direction_output+0x38/0x94
  gpiod_direction_output_raw_commit+0x1d8/0x360
  gpiod_direction_output_nonotify+0x7c/0x230
  gpiod_direction_output+0x34/0xf8
  gpio_shared_proxy_direction_output+0xec/0x144 [gpio_shared_proxy]
  gpiochip_direction_output+0x38/0x94
  gpiod_direction_output_raw_commit+0x1d8/0x360
  gpiod_direction_output_nonotify+0x7c/0x230
  gpiod_configure_flags+0xbc/0x480
  gpiod_find_and_request+0x1a0/0x574
  gpiod_get_index+0x58/0x84
  devm_gpiod_get_index+0x20/0xb4
  devm_gpiod_get_optional+0x18/0x30
  rockchip_pcie_probe+0x98/0x380
  platform_probe+0x5c/0xac
  really_probe+0xbc/0x298

Fixes: 936ee26 ("gpio/rockchip: add driver for rockchip gpio")
Cc: stable@vger.kernel.org
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Closes: https://lore.kernel.org/all/d035fc29-3b03-4cd6-b8ec-001f93540bc6@samsung.com/
Acked-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20260106090011.21603-1-bartosz.golaszewski@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
…ked_inode()

In btrfs_read_locked_inode() we are calling btrfs_init_file_extent_tree()
while holding a path with a read locked leaf from a subvolume tree, and
btrfs_init_file_extent_tree() may do a GFP_KERNEL allocation, which can
trigger reclaim.

This can create a circular lock dependency which lockdep warns about with
the following splat:

   [6.1433] ======================================================
   [6.1574] WARNING: possible circular locking dependency detected
   [6.1583] 6.18.0+ #4 Tainted: G     U
   [6.1591] ------------------------------------------------------
   [6.1599] kswapd0/117 is trying to acquire lock:
   [6.1606] ffff8d9b6333c5b8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1625]
            but task is already holding lock:
   [6.1633] ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
   [6.1646]
            which lock already depends on the new lock.

   [6.1657]
            the existing dependency chain (in reverse order) is:
   [6.1667]
            -> #2 (fs_reclaim){+.+.}-{0:0}:
   [6.1677]        fs_reclaim_acquire+0x9d/0xd0
   [6.1685]        __kmalloc_cache_noprof+0x59/0x750
   [6.1694]        btrfs_init_file_extent_tree+0x90/0x100
   [6.1702]        btrfs_read_locked_inode+0xc3/0x6b0
   [6.1710]        btrfs_iget+0xbb/0xf0
   [6.1716]        btrfs_lookup_dentry+0x3c5/0x8e0
   [6.1724]        btrfs_lookup+0x12/0x30
   [6.1731]        lookup_open.isra.0+0x1aa/0x6a0
   [6.1739]        path_openat+0x5f7/0xc60
   [6.1746]        do_filp_open+0xd6/0x180
   [6.1753]        do_sys_openat2+0x8b/0xe0
   [6.1760]        __x64_sys_openat+0x54/0xa0
   [6.1768]        do_syscall_64+0x97/0x3e0
   [6.1776]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [6.1784]
            -> #1 (btrfs-tree-00){++++}-{3:3}:
   [6.1794]        lock_release+0x127/0x2a0
   [6.1801]        up_read+0x1b/0x30
   [6.1808]        btrfs_search_slot+0x8e0/0xff0
   [6.1817]        btrfs_lookup_inode+0x52/0xd0
   [6.1825]        __btrfs_update_delayed_inode+0x73/0x520
   [6.1833]        btrfs_commit_inode_delayed_inode+0x11a/0x120
   [6.1842]        btrfs_log_inode+0x608/0x1aa0
   [6.1849]        btrfs_log_inode_parent+0x249/0xf80
   [6.1857]        btrfs_log_dentry_safe+0x3e/0x60
   [6.1865]        btrfs_sync_file+0x431/0x690
   [6.1872]        do_fsync+0x39/0x80
   [6.1879]        __x64_sys_fsync+0x13/0x20
   [6.1887]        do_syscall_64+0x97/0x3e0
   [6.1894]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
   [6.1903]
            -> #0 (&delayed_node->mutex){+.+.}-{3:3}:
   [6.1913]        __lock_acquire+0x15e9/0x2820
   [6.1920]        lock_acquire+0xc9/0x2d0
   [6.1927]        __mutex_lock+0xcc/0x10a0
   [6.1934]        __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1944]        btrfs_evict_inode+0x20b/0x4b0
   [6.1952]        evict+0x15a/0x2f0
   [6.1958]        prune_icache_sb+0x91/0xd0
   [6.1966]        super_cache_scan+0x150/0x1d0
   [6.1974]        do_shrink_slab+0x155/0x6f0
   [6.1981]        shrink_slab+0x48e/0x890
   [6.1988]        shrink_one+0x11a/0x1f0
   [6.1995]        shrink_node+0xbfd/0x1320
   [6.1002]        balance_pgdat+0x67f/0xc60
   [6.1321]        kswapd+0x1dc/0x3e0
   [6.1643]        kthread+0xff/0x240
   [6.1965]        ret_from_fork+0x223/0x280
   [6.1287]        ret_from_fork_asm+0x1a/0x30
   [6.1616]
            other info that might help us debug this:

   [6.1561] Chain exists of:
              &delayed_node->mutex --> btrfs-tree-00 --> fs_reclaim

   [6.1503]  Possible unsafe locking scenario:

   [6.1110]        CPU0                    CPU1
   [6.1411]        ----                    ----
   [6.1707]   lock(fs_reclaim);
   [6.1998]                                lock(btrfs-tree-00);
   [6.1291]                                lock(fs_reclaim);
   [6.1581]   lock(&delayed_node->mutex);
   [6.1874]
             *** DEADLOCK ***

   [6.1716] 2 locks held by kswapd0/117:
   [6.1999]  #0: ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
   [6.1294]  #1: ffff8d998344b0e0 (&type->s_umount_key#40){++++}- {3:3}, at: super_cache_scan+0x37/0x1d0
   [6.1596]
            stack backtrace:
   [6.1183] CPU: 11 UID: 0 PID: 117 Comm: kswapd0 Tainted: G     U 6.18.0+ #4 PREEMPT(lazy)
   [6.1185] Tainted: [U]=USER
   [6.1186] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
   [6.1187] Call Trace:
   [6.1187]  <TASK>
   [6.1189]  dump_stack_lvl+0x6e/0xa0
   [6.1192]  print_circular_bug.cold+0x17a/0x1c0
   [6.1194]  check_noncircular+0x175/0x190
   [6.1197]  __lock_acquire+0x15e9/0x2820
   [6.1200]  lock_acquire+0xc9/0x2d0
   [6.1201]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1204]  __mutex_lock+0xcc/0x10a0
   [6.1206]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1208]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1211]  ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1213]  __btrfs_release_delayed_node.part.0+0x39/0x2f0
   [6.1215]  btrfs_evict_inode+0x20b/0x4b0
   [6.1217]  ? lock_acquire+0xc9/0x2d0
   [6.1220]  evict+0x15a/0x2f0
   [6.1222]  prune_icache_sb+0x91/0xd0
   [6.1224]  super_cache_scan+0x150/0x1d0
   [6.1226]  do_shrink_slab+0x155/0x6f0
   [6.1228]  shrink_slab+0x48e/0x890
   [6.1229]  ? shrink_slab+0x2d2/0x890
   [6.1231]  shrink_one+0x11a/0x1f0
   [6.1234]  shrink_node+0xbfd/0x1320
   [6.1236]  ? shrink_node+0xa2d/0x1320
   [6.1236]  ? shrink_node+0xbd3/0x1320
   [6.1239]  ? balance_pgdat+0x67f/0xc60
   [6.1239]  balance_pgdat+0x67f/0xc60
   [6.1241]  ? finish_task_switch.isra.0+0xc4/0x2a0
   [6.1246]  kswapd+0x1dc/0x3e0
   [6.1247]  ? __pfx_autoremove_wake_function+0x10/0x10
   [6.1249]  ? __pfx_kswapd+0x10/0x10
   [6.1250]  kthread+0xff/0x240
   [6.1251]  ? __pfx_kthread+0x10/0x10
   [6.1253]  ret_from_fork+0x223/0x280
   [6.1255]  ? __pfx_kthread+0x10/0x10
   [6.1257]  ret_from_fork_asm+0x1a/0x30
   [6.1260]  </TASK>

This is because:

1) The fsync task is holding an inode's delayed node mutex (for a
   directory) while calling __btrfs_update_delayed_inode() and that needs
   to do a search on the subvolume's btree (therefore read lock some
   extent buffers);

2) The lookup task, at btrfs_lookup(), triggered reclaim with the
   GFP_KERNEL allocation done by btrfs_init_file_extent_tree() while
   holding a read lock on a subvolume leaf;

3) The reclaim triggered kswapd which is doing inode eviction for the
   directory inode the fsync task is using as an argument to
   btrfs_commit_inode_delayed_inode() - but in that call chain we are
   trying to read lock the same leaf that the lookup task is holding
   while calling btrfs_init_file_extent_tree() and doing the GFP_KERNEL
   allocation.

Fix this by calling btrfs_init_file_extent_tree() after we don't need the
path anymore and release it in btrfs_read_locked_inode().

Reported-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://lore.kernel.org/linux-btrfs/6e55113a22347c3925458a5d840a18401a38b276.camel@linux.intel.com/
Fixes: 8679d26 ("btrfs: initialize inode::file_extent_tree after i_mode has been set")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
When forward-porting Rust Binder to 6.18, I neglected to take commit
fb56fdf ("mm/list_lru: split the lock to per-cgroup scope") into
account, and apparently I did not end up running the shrinker callback
when I sanity tested the driver before submission. This leads to crashes
like the following:

	============================================
	WARNING: possible recursive locking detected
	6.18.0-mainline-maybe-dirty #1 Tainted: G          IO
	--------------------------------------------
	kswapd0/68 is trying to acquire lock:
	ffff956000fa18b0 (&l->lock){+.+.}-{2:2}, at: lock_list_lru_of_memcg+0x128/0x230

	but task is already holding lock:
	ffff956000fa18b0 (&l->lock){+.+.}-{2:2}, at: rust_helper_spin_lock+0xd/0x20

	other info that might help us debug this:
	 Possible unsafe locking scenario:

	       CPU0
	       ----
	  lock(&l->lock);
	  lock(&l->lock);

	 *** DEADLOCK ***

	 May be due to missing lock nesting notation

	3 locks held by kswapd0/68:
	 #0: ffffffff90d2e260 (fs_reclaim){+.+.}-{0:0}, at: kswapd+0x597/0x1160
	 #1: ffff956000fa18b0 (&l->lock){+.+.}-{2:2}, at: rust_helper_spin_lock+0xd/0x20
	 #2: ffffffff90cf3680 (rcu_read_lock){....}-{1:2}, at: lock_list_lru_of_memcg+0x2d/0x230

To fix this, remove the spin_lock() call from rust_shrink_free_page().

Cc: stable <stable@kernel.org>
Fixes: eafedbc ("rust_binder: add Rust Binder driver")
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20251202-binder-shrink-unspin-v1-1-263efb9ad625@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
krishnachaitanya-linux pushed a commit that referenced this pull request Feb 24, 2026
During device unmapping (triggered by module unload or explicit unmap),
a refcount underflow occurs causing a use-after-free warning:

  [14747.574913] ------------[ cut here ]------------
  [14747.574916] refcount_t: underflow; use-after-free.
  [14747.574917] WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x55/0x90, CPU#9: kworker/9:1/378
  [14747.574924] Modules linked in: rnbd_client(-) rtrs_client rnbd_server rtrs_server rtrs_core ...
  [14747.574998] CPU: 9 UID: 0 PID: 378 Comm: kworker/9:1 Tainted: G           O     N  6.19.0-rc3lblk-fnext+ #42 PREEMPT(voluntary)
  [14747.575005] Workqueue: rnbd_clt_wq unmap_device_work [rnbd_client]
  [14747.575010] RIP: 0010:refcount_warn_saturate+0x55/0x90
  [14747.575037]  Call Trace:
  [14747.575038]   <TASK>
  [14747.575038]   rnbd_clt_unmap_device+0x170/0x1d0 [rnbd_client]
  [14747.575044]   process_one_work+0x211/0x600
  [14747.575052]   worker_thread+0x184/0x330
  [14747.575055]   ? __pfx_worker_thread+0x10/0x10
  [14747.575058]   kthread+0x10d/0x250
  [14747.575062]   ? __pfx_kthread+0x10/0x10
  [14747.575066]   ret_from_fork+0x319/0x390
  [14747.575069]   ? __pfx_kthread+0x10/0x10
  [14747.575072]   ret_from_fork_asm+0x1a/0x30
  [14747.575083]   </TASK>
  [14747.575096] ---[ end trace 0000000000000000 ]---

Befor this patch :-

The bug is a double kobject_put() on dev->kobj during device cleanup.

Kobject Lifecycle:
  kobject_init_and_add()  sets kobj.kref = 1  (initialization)
  kobject_put()           sets kobj.kref = 0  (should be called once)

* Before this patch:

rnbd_clt_unmap_device()
  rnbd_destroy_sysfs()
    kobject_del(&dev->kobj)                   [remove from sysfs]
    kobject_put(&dev->kobj)                   PUT #1 (WRONG!)
      kref: 1 to 0
      rnbd_dev_release()
        kfree(dev)                            [DEVICE FREED!]

  rnbd_destroy_gen_disk()                     [use-after-free!]

  rnbd_clt_put_dev()
    refcount_dec_and_test(&dev->refcount)
    kobject_put(&dev->kobj)                   PUT #2 (UNDERFLOW!)
      kref: 0 to -1                           [WARNING!]

The first kobject_put() in rnbd_destroy_sysfs() prematurely frees the
device via rnbd_dev_release(), then the second kobject_put() in
rnbd_clt_put_dev() causes refcount underflow.

* After this patch :-

Remove kobject_put() from rnbd_destroy_sysfs(). This function should
only remove sysfs visibility (kobject_del), not manage object lifetime.

Call Graph (FIXED):

rnbd_clt_unmap_device()
  rnbd_destroy_sysfs()
    kobject_del(&dev->kobj)                   [remove from sysfs only]
                                              [kref unchanged: 1]

  rnbd_destroy_gen_disk()                     [device still valid]

  rnbd_clt_put_dev()
    refcount_dec_and_test(&dev->refcount)
    kobject_put(&dev->kobj)                   ONLY PUT (CORRECT!)
      kref: 1 to 0                            [BALANCED]
      rnbd_dev_release()
        kfree(dev)                            [CLEAN DESTRUCTION]

This follows the kernel pattern where sysfs removal (kobject_del) is
separate from object destruction (kobject_put).

Fixes: 581cf83 ("block: rnbd: add .release to rnbd_dev_ktype")
Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant