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scx: Remove unnecessary pr_err on ops.prep_enable() failure path #18

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When ops.prep_enable() returns an error code that is propagated through scx_ops_prepare_task(), we currently issue a pr_err from scx_ops_enable(). It seems wrong for a BPF prog to be able to cause the kernel to issue a pr_err message, and we already capture the error in an ops_sanitizer_err() call in scx_ops_prepare_task(). Let's remove it.

When ops.prep_enable() returns an error code that is propagated through
scx_ops_prepare_task(), we currently issue a pr_err from
scx_ops_enable(). It seems wrong for a BPF prog to be able to cause the
kernel to issue a pr_err message, and we already capture the error in an
ops_sanitizer_err() call in scx_ops_prepare_task(). Let's remove it.

Signed-off-by: David Vernet <void@manifault.com>
@Byte-Lab Byte-Lab requested a review from htejun June 10, 2023 04:07
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Tabling this for now -- we don't print the task name on the ops_sanitize_err() path. We can improve sanitize error messaging and generate a custom message in the init path later.

@Byte-Lab Byte-Lab closed this Jun 10, 2023
@Byte-Lab Byte-Lab deleted the remove_prerr branch June 10, 2023 04:26
htejun pushed a commit that referenced this pull request Nov 5, 2023
The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Byte-Lab pushed a commit that referenced this pull request Nov 7, 2023
Andrii Nakryiko says:

====================
BPF register bounds logic and testing improvements

This patch set adds a big set of manual and auto-generated test cases
validating BPF verifier's register bounds tracking and deduction logic. See
details in the last patch.

We start with building a tester that validates existing <range> vs <scalar>
verifier logic for range bounds. To make all this work, BPF verifier's logic
needed a bunch of improvements to handle some cases that previously were not
covered. This had no implications as to correctness of verifier logic, but it
was incomplete enough to cause significant disagreements with alternative
implementation of register bounds logic that tests in this patch set
implement. So we need BPF verifier logic improvements to make all the tests
pass. This is what we do in patches #3 through #9.

The end goal of this work, though, is to extend BPF verifier range state
tracking such as to allow to derive new range bounds when comparing non-const
registers. There is some more investigative work required to investigate and
fix existing potential issues with range tracking as part of ALU/ALU64
operations, so <range> x <range> part of v5 patch set ([0]) is dropped until
these issues are sorted out.

For now, we include preparatory refactorings and clean ups, that set up BPF
verifier code base to extend the logic to <range> vs <range> logic in
subsequent patch set. Patches #10-#16 perform preliminary refactorings without
functionally changing anything. But they do clean up check_cond_jmp_op() logic
and generalize a bunch of other pieces in is_branch_taken() logic.

  [0] https://patchwork.kernel.org/project/netdevbpf/list/?series=797178&state=*

v5->v6:
  - dropped <range> vs <range> patches (original patches #18 through #23) to
    add more register range sanity checks and fix preexisting issues;
  - comments improvements, addressing other feedback on first 17 patches
    (Eduard, Alexei);
v4->v5:
  - added entirety of verifier reg bounds tracking changes, now handling
    <range> vs <range> cases (Alexei);
  - added way more comments trying to explain why deductions added are
    correct, hopefully they are useful and clarify things a bit (Daniel,
    Shung-Hsi);
  - added two preliminary selftests fixes necessary for RELEASE=1 build to
    work again, it keeps breaking.
v3->v4:
  - improvements to reg_bounds tester (progress report, split 32-bit and
    64-bit ranges, fix various verbosity output issues, etc);
v2->v3:
  - fix a subtle little-endianness assumption inside parge_reg_state() (CI);
v1->v2:
  - fix compilation when building selftests with llvm-16 toolchain (CI).
====================

Link: https://lore.kernel.org/r/20231102033759.2541186-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Byte-Lab pushed a commit that referenced this pull request Jan 8, 2024
When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn
Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com>
Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn>
Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
htejun pushed a commit that referenced this pull request Mar 29, 2024
sg_init_one() relies on linearly mapped low memory for the safe
utilization of virt_to_page().  Otherwise, we trigger a kernel BUG,

kernel BUG at include/linux/scatterlist.h:187!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
Modules linked in:
CPU: 0 PID: 2997 Comm: syz-executor198 Not tainted 6.8.0-syzkaller #0
Hardware name: ARM-Versatile Express
PC is at sg_set_buf include/linux/scatterlist.h:187 [inline]
PC is at sg_init_one+0x9c/0xa8 lib/scatterlist.c:143
LR is at sg_init_table+0x2c/0x40 lib/scatterlist.c:128
Backtrace:
[<807e16ac>] (sg_init_one) from [<804c1824>] (zswap_decompress+0xbc/0x208 mm/zswap.c:1089)
 r7:83471c80 r6:def6d08c r5:844847d0 r4:ff7e7ef4
[<804c1768>] (zswap_decompress) from [<804c4468>] (zswap_load+0x15c/0x198 mm/zswap.c:1637)
 r9:8446eb80 r8:8446eb80 r7:8446eb84 r6:def6d08c r5:00000001 r4:844847d0
[<804c430c>] (zswap_load) from [<804b9644>] (swap_read_folio+0xa8/0x498 mm/page_io.c:518)
 r9:844ac800 r8:835e6c00 r7:00000000 r6:df955d4c r5:00000001 r4:def6d08c
[<804b959c>] (swap_read_folio) from [<804bb064>] (swap_cluster_readahead+0x1c4/0x34c mm/swap_state.c:684)
 r10:00000000 r9:00000007 r8:df955d4b r7:00000000 r6:00000000 r5:00100cca
 r4:00000001
[<804baea0>] (swap_cluster_readahead) from [<804bb3b8>] (swapin_readahead+0x68/0x4a8 mm/swap_state.c:904)
 r10:df955eb8 r9:00000000 r8:00100cca r7:84476480 r6:00000001 r5:00000000
 r4:00000001
[<804bb350>] (swapin_readahead) from [<8047cde0>] (do_swap_page+0x200/0xcc4 mm/memory.c:4046)
 r10:00000040 r9:00000000 r8:844ac800 r7:84476480 r6:00000001 r5:00000000
 r4:df955eb8
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (handle_pte_fault mm/memory.c:5301 [inline])
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (__handle_mm_fault mm/memory.c:5439 [inline])
[<8047cbe0>] (do_swap_page) from [<8047e6c4>] (handle_mm_fault+0x3d8/0x12b8 mm/memory.c:5604)
 r10:00000040 r9:842b3900 r8:7eb0d000 r7:84476480 r6:7eb0d000 r5:835e6c00
 r4:00000254
[<8047e2ec>] (handle_mm_fault) from [<80215d28>] (do_page_fault+0x148/0x3a8 arch/arm/mm/fault.c:326)
 r10:00000007 r9:842b3900 r8:7eb0d000 r7:00000207 r6:00000254 r5:7eb0d9b4
 r4:df955fb0
[<80215be0>] (do_page_fault) from [<80216170>] (do_DataAbort+0x38/0xa8 arch/arm/mm/fault.c:558)
 r10:7eb0da7c r9:00000000 r8:80215be0 r7:df955fb0 r6:7eb0d9b4 r5:00000207
 r4:8261d0e0
[<80216138>] (do_DataAbort) from [<80200e3c>] (__dabt_usr+0x5c/0x60 arch/arm/kernel/entry-armv.S:427)
Exception stack(0xdf955fb0 to 0xdf955ff8)
5fa0:                                     00000000 00000000 22d5f800 0008d158
5fc0: 00000000 7eb0d9a4 00000000 00000109 00000000 00000000 7eb0da7c 7eb0da3c
5fe0: 00000000 7eb0d9a0 00000001 00066bd4 00000010 ffffffff
 r8:824a9044 r7:835e6c00 r6:ffffffff r5:00000010 r4:00066bd4
Code: 1a000004 e1822003 e8860094 e89da8f0 (e7f001f2)
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	1a000004 	bne	0x18
   4:	e1822003 	orr	r2, r2, r3
   8:	e8860094 	stm	r6, {r2, r4, r7}
   c:	e89da8f0 	ldm	sp, {r4, r5, r6, r7, fp, sp, pc}
* 10:	e7f001f2 	udf	#18 <-- trapping instruction

Consequently, we have two choices: either employ kmap_to_page() alongside
sg_set_page(), or resort to copying high memory contents to a temporary
buffer residing in low memory.  However, considering the introduction of
the WARN_ON_ONCE in commit ef6e06b ("highmem: fix kmap_to_page() for
kmap_local_page() addresses"), which specifically addresses high memory
concerns, it appears that memcpy remains the sole viable option.

Link: https://lkml.kernel.org/r/20240318234706.95347-1-21cnbao@gmail.com
Fixes: 270700d ("mm/zswap: remove the memcpy if acomp is not sleepable")
Signed-off-by: Barry Song <v-songbaohua@oppo.com>
Reported-by: syzbot+adbc983a1588b7805de3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000bbb3d80613f243a6@google.com/
Tested-by: syzbot+adbc983a1588b7805de3@syzkaller.appspotmail.com
Acked-by: Yosry Ahmed <yosryahmed@google.com>
Reviewed-by: Nhat Pham <nphamcs@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
arighi pushed a commit to arighi/sched_ext that referenced this pull request Jun 7, 2024
BugLink: https://bugs.launchpad.net/bugs/2068087

[ Upstream commit f8bbc07 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 sched-ext#1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 sched-ext#2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 sched-ext#3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 sched-ext#4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 sched-ext#5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 sched-ext#6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 sched-ext#7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 sched-ext#8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 sched-ext#9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 sched-ext#10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 sched-ext#11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 sched-ext#12 [ffffa65531497b68] printk at ffffffff89318306
 sched-ext#13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 sched-ext#14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 sched-ext#15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 sched-ext#16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 sched-ext#17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 sched-ext#18 [ffffa65531497f10] kthread at ffffffff892d2e72
 sched-ext#19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
htejun pushed a commit that referenced this pull request Jun 17, 2024
…rnel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

Patch #1 skips transaction if object type provides no .update interface.

Patch #2 skips NETDEV_CHANGENAME which is unused.

Patch #3 enables conntrack to handle Multicast Router Advertisements and
	 Multicast Router Solicitations from the Multicast Router Discovery
	 protocol (RFC4286) as untracked opposed to invalid packets.
	 From Linus Luessing.

Patch #4 updates DCCP conntracker to mark invalid as invalid, instead of
	 dropping them, from Jason Xing.

Patch #5 uses NF_DROP instead of -NF_DROP since NF_DROP is 0,
	 also from Jason.

Patch #6 removes reference in netfilter's sysctl documentation on pickup
	 entries which were already removed by Florian Westphal.

Patch #7 removes check for IPS_OFFLOAD flag to disable early drop which
	 allows to evict entries from the conntrack table,
	 also from Florian.

Patches #8 to #16 updates nf_tables pipapo set backend to allocate
	 the datastructure copy on-demand from preparation phase,
	 to better deal with OOM situations where .commit step is too late
	 to fail. Series from Florian Westphal.

Patch #17 adds a selftest with packetdrill to cover conntrack TCP state
	 transitions, also from Florian.

Patch #18 use GFP_KERNEL to clone elements from control plane to avoid
	 quick atomic reserves exhaustion with large sets, reporter refers
	 to million entries magnitude.

* tag 'nf-next-24-05-12' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: allow clone callbacks to sleep
  selftests: netfilter: add packetdrill based conntrack tests
  netfilter: nft_set_pipapo: remove dirty flag
  netfilter: nft_set_pipapo: move cloning of match info to insert/removal path
  netfilter: nft_set_pipapo: prepare pipapo_get helper for on-demand clone
  netfilter: nft_set_pipapo: merge deactivate helper into caller
  netfilter: nft_set_pipapo: prepare walk function for on-demand clone
  netfilter: nft_set_pipapo: prepare destroy function for on-demand clone
  netfilter: nft_set_pipapo: make pipapo_clone helper return NULL
  netfilter: nft_set_pipapo: move prove_locking helper around
  netfilter: conntrack: remove flowtable early-drop test
  netfilter: conntrack: documentation: remove reference to non-existent sysctl
  netfilter: use NF_DROP instead of -NF_DROP
  netfilter: conntrack: dccp: try not to drop skb in conntrack
  netfilter: conntrack: fix ct-state for ICMPv6 Multicast Router Discovery
  netfilter: nf_tables: remove NETDEV_CHANGENAME from netdev chain event handler
  netfilter: nf_tables: skip transaction if update object is not implemented
====================

Link: https://lore.kernel.org/r/20240512161436.168973-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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