Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Enable the R5900 floating-point unit (FPU) #3

Open
frno7 opened this issue Mar 2, 2019 · 0 comments
Open

Enable the R5900 floating-point unit (FPU) #3

frno7 opened this issue Mar 2, 2019 · 0 comments
Labels
enhancement New feature or request

Comments

@frno7
Copy link
Owner

frno7 commented Mar 2, 2019

The R5900 floating-point unit (FPU) is not compliant with the IEEE 754 standard. To comply with the o32 and n32 Linux ABIs, the FPU is therefore emulated in software by the Linux kernel. This emulation is accurate but very slow. One suggestion is to introduce a new ELF ABI annotation that switches the floating-point environment between IEEE 754 emulation and the R5900 FPU in hardware.

In particular, with the R5900 FPU

  • NaN (not a number) and plus/minus infinities are not supported;
  • exception mechanisms are not fully supported;
  • denormalized numbers are not supported;
  • rounding towards nearest and plus/minus infinities are not supported;
  • computed results usually differs in the least significant bit;
  • saturating instructions can differ more than the least significant bit.

Since only rounding towards zero is supported, the two least significant bits of FCR31 are hardwired to 01.

Finally, the R5900 FPU has some anomalies in the instruction set; not all opcode encodings are standard and some opcodes are extra. The output of the command grep 'FP_.*EE' binutils/opcodes/mips-opc.c with EE in the membership field are extra, and those with EE in the exclusions field are missing. See [PATCH] Support for MIPS R5900 (Sony Playstation 2).

A good start to this issue is to setup a small FPU test suite, with the critical parts of the tests written in MIPS assembly. The tests can answer the question of what is, and isn’t, working with the current FPU emulation for the o32 ABI. They can also be used to measure progress, including benchmarking, when improving tooling and the kernel for complete FPU support.

See also R5900 QEMU #5.

@frno7 frno7 added the enhancement New feature or request label Mar 2, 2019
frno7 pushed a commit that referenced this issue Apr 19, 2019
commit 9f0bbf3 upstream.

Because there may be random garbage beyond a string's null terminator,
it's not correct to copy the the complete character array for use as a
hist trigger key.  This results in multiple histogram entries for the
'same' string key.

So, in the case of a string key, use strncpy instead of memcpy to
avoid copying in the extra bytes.

Before, using the gdbus entries in the following hist trigger as an
example:

  # echo 'hist:key=comm' > /sys/kernel/debug/tracing/events/sched/sched_waking/trigger
  # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist

  ...

  { comm: ImgDecoder #4                      } hitcount:        203
  { comm: gmain                              } hitcount:        213
  { comm: gmain                              } hitcount:        216
  { comm: StreamTrans #73                    } hitcount:        221
  { comm: mozStorage #3                      } hitcount:        230
  { comm: gdbus                              } hitcount:        233
  { comm: StyleThread#5                      } hitcount:        253
  { comm: gdbus                              } hitcount:        256
  { comm: gdbus                              } hitcount:        260
  { comm: StyleThread#4                      } hitcount:        271

  ...

  # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist | egrep gdbus | wc -l
  51

After:

  # cat /sys/kernel/debug/tracing/events/sched/sched_waking/hist | egrep gdbus | wc -l
  1

Link: http://lkml.kernel.org/r/50c35ae1267d64eee975b8125e151e600071d4dc.1549309756.git.tom.zanussi@linux.intel.com

Cc: Namhyung Kim <namhyung@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 79e577c ("tracing: Support string type key properly")
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
commit 1cec3f2 upstream.

This fixes a longstanding lockdep warning triggered by
fstests/btrfs/011.

Circular locking dependency check reports warning[1], that's because the
btrfs_scrub_dev() calls the stack #0 below with, the fs_info::scrub_lock
held. The test case leading to this warning:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /btrfs
  $ btrfs scrub start -B /btrfs

In fact we have fs_info::scrub_workers_refcnt to track if the init and destroy
of the scrub workers are needed. So once we have incremented and decremented
the fs_info::scrub_workers_refcnt value in the thread, its ok to drop the
scrub_lock, and then actually do the btrfs_destroy_workqueue() part. So this
patch drops the scrub_lock before calling btrfs_destroy_workqueue().

  [359.258534] ======================================================
  [359.260305] WARNING: possible circular locking dependency detected
  [359.261938] 5.0.0-rc6-default torvalds#461 Not tainted
  [359.263135] ------------------------------------------------------
  [359.264672] btrfs/20975 is trying to acquire lock:
  [359.265927] 00000000d4d32bea ((wq_completion)"%s-%s""btrfs", name){+.+.}, at: flush_workqueue+0x87/0x540
  [359.268416]
  [359.268416] but task is already holding lock:
  [359.270061] 0000000053ea26a6 (&fs_info->scrub_lock){+.+.}, at: btrfs_scrub_dev+0x322/0x590 [btrfs]
  [359.272418]
  [359.272418] which lock already depends on the new lock.
  [359.272418]
  [359.274692]
  [359.274692] the existing dependency chain (in reverse order) is:
  [359.276671]
  [359.276671] -> #3 (&fs_info->scrub_lock){+.+.}:
  [359.278187]        __mutex_lock+0x86/0x9c0
  [359.279086]        btrfs_scrub_pause+0x31/0x100 [btrfs]
  [359.280421]        btrfs_commit_transaction+0x1e4/0x9e0 [btrfs]
  [359.281931]        close_ctree+0x30b/0x350 [btrfs]
  [359.283208]        generic_shutdown_super+0x64/0x100
  [359.284516]        kill_anon_super+0x14/0x30
  [359.285658]        btrfs_kill_super+0x12/0xa0 [btrfs]
  [359.286964]        deactivate_locked_super+0x29/0x60
  [359.288242]        cleanup_mnt+0x3b/0x70
  [359.289310]        task_work_run+0x98/0xc0
  [359.290428]        exit_to_usermode_loop+0x83/0x90
  [359.291445]        do_syscall_64+0x15b/0x180
  [359.292598]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [359.294011]
  [359.294011] -> #2 (sb_internal#2){.+.+}:
  [359.295432]        __sb_start_write+0x113/0x1d0
  [359.296394]        start_transaction+0x369/0x500 [btrfs]
  [359.297471]        btrfs_finish_ordered_io+0x2aa/0x7c0 [btrfs]
  [359.298629]        normal_work_helper+0xcd/0x530 [btrfs]
  [359.299698]        process_one_work+0x246/0x610
  [359.300898]        worker_thread+0x3c/0x390
  [359.302020]        kthread+0x116/0x130
  [359.303053]        ret_from_fork+0x24/0x30
  [359.304152]
  [359.304152] -> #1 ((work_completion)(&work->normal_work)){+.+.}:
  [359.306100]        process_one_work+0x21f/0x610
  [359.307302]        worker_thread+0x3c/0x390
  [359.308465]        kthread+0x116/0x130
  [359.309357]        ret_from_fork+0x24/0x30
  [359.310229]
  [359.310229] -> #0 ((wq_completion)"%s-%s""btrfs", name){+.+.}:
  [359.311812]        lock_acquire+0x90/0x180
  [359.312929]        flush_workqueue+0xaa/0x540
  [359.313845]        drain_workqueue+0xa1/0x180
  [359.314761]        destroy_workqueue+0x17/0x240
  [359.315754]        btrfs_destroy_workqueue+0x57/0x200 [btrfs]
  [359.317245]        scrub_workers_put+0x2c/0x60 [btrfs]
  [359.318585]        btrfs_scrub_dev+0x336/0x590 [btrfs]
  [359.319944]        btrfs_dev_replace_by_ioctl.cold.19+0x179/0x1bb [btrfs]
  [359.321622]        btrfs_ioctl+0x28a4/0x2e40 [btrfs]
  [359.322908]        do_vfs_ioctl+0xa2/0x6d0
  [359.324021]        ksys_ioctl+0x3a/0x70
  [359.325066]        __x64_sys_ioctl+0x16/0x20
  [359.326236]        do_syscall_64+0x54/0x180
  [359.327379]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [359.328772]
  [359.328772] other info that might help us debug this:
  [359.328772]
  [359.330990] Chain exists of:
  [359.330990]   (wq_completion)"%s-%s""btrfs", name --> sb_internal#2 --> &fs_info->scrub_lock
  [359.330990]
  [359.334376]  Possible unsafe locking scenario:
  [359.334376]
  [359.336020]        CPU0                    CPU1
  [359.337070]        ----                    ----
  [359.337821]   lock(&fs_info->scrub_lock);
  [359.338506]                                lock(sb_internal#2);
  [359.339506]                                lock(&fs_info->scrub_lock);
  [359.341461]   lock((wq_completion)"%s-%s""btrfs", name);
  [359.342437]
  [359.342437]  *** DEADLOCK ***
  [359.342437]
  [359.343745] 1 lock held by btrfs/20975:
  [359.344788]  #0: 0000000053ea26a6 (&fs_info->scrub_lock){+.+.}, at: btrfs_scrub_dev+0x322/0x590 [btrfs]
  [359.346778]
  [359.346778] stack backtrace:
  [359.347897] CPU: 0 PID: 20975 Comm: btrfs Not tainted 5.0.0-rc6-default torvalds#461
  [359.348983] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626cc-prebuilt.qemu-project.org 04/01/2014
  [359.350501] Call Trace:
  [359.350931]  dump_stack+0x67/0x90
  [359.351676]  print_circular_bug.isra.37.cold.56+0x15c/0x195
  [359.353569]  check_prev_add.constprop.44+0x4f9/0x750
  [359.354849]  ? check_prev_add.constprop.44+0x286/0x750
  [359.356505]  __lock_acquire+0xb84/0xf10
  [359.357505]  lock_acquire+0x90/0x180
  [359.358271]  ? flush_workqueue+0x87/0x540
  [359.359098]  flush_workqueue+0xaa/0x540
  [359.359912]  ? flush_workqueue+0x87/0x540
  [359.360740]  ? drain_workqueue+0x1e/0x180
  [359.361565]  ? drain_workqueue+0xa1/0x180
  [359.362391]  drain_workqueue+0xa1/0x180
  [359.363193]  destroy_workqueue+0x17/0x240
  [359.364539]  btrfs_destroy_workqueue+0x57/0x200 [btrfs]
  [359.365673]  scrub_workers_put+0x2c/0x60 [btrfs]
  [359.366618]  btrfs_scrub_dev+0x336/0x590 [btrfs]
  [359.367594]  ? start_transaction+0xa1/0x500 [btrfs]
  [359.368679]  btrfs_dev_replace_by_ioctl.cold.19+0x179/0x1bb [btrfs]
  [359.369545]  btrfs_ioctl+0x28a4/0x2e40 [btrfs]
  [359.370186]  ? __lock_acquire+0x263/0xf10
  [359.370777]  ? kvm_clock_read+0x14/0x30
  [359.371392]  ? kvm_sched_clock_read+0x5/0x10
  [359.372248]  ? sched_clock+0x5/0x10
  [359.372786]  ? sched_clock_cpu+0xc/0xc0
  [359.373662]  ? do_vfs_ioctl+0xa2/0x6d0
  [359.374552]  do_vfs_ioctl+0xa2/0x6d0
  [359.375378]  ? do_sigaction+0xff/0x250
  [359.376233]  ksys_ioctl+0x3a/0x70
  [359.376954]  __x64_sys_ioctl+0x16/0x20
  [359.377772]  do_syscall_64+0x54/0x180
  [359.378841]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [359.380422] RIP: 0033:0x7f5429296a97

Backporting to older kernels: scrub_nocow_workers must be freed the same
way as the others.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ update changelog ]
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
commit 9951379 upstream.

Some users see panics like the following when performing fstrim on a
bcached volume:

[  529.803060] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[  530.183928] #PF error: [normal kernel read fault]
[  530.412392] PGD 8000001f42163067 P4D 8000001f42163067 PUD 1f42168067 PMD 0
[  530.750887] Oops: 0000 [#1] SMP PTI
[  530.920869] CPU: 10 PID: 4167 Comm: fstrim Kdump: loaded Not tainted 5.0.0-rc1+ #3
[  531.290204] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 12/27/2015
[  531.693137] RIP: 0010:blk_queue_split+0x148/0x620
[  531.922205] Code: 60 38 89 55 a0 45 31 db 45 31 f6 45 31 c9 31 ff 89 4d 98 85 db 0f 84 7f 04 00 00 44 8b 6d 98 4c 89 ee 48 c1 e6 04 49 03 70 78 <8b> 46 08 44 8b 56 0c 48
8b 16 44 29 e0 39 d8 48 89 55 a8 0f 47 c3
[  532.838634] RSP: 0018:ffffb9b708df39b0 EFLAGS: 00010246
[  533.093571] RAX: 00000000ffffffff RBX: 0000000000046000 RCX: 0000000000000000
[  533.441865] RDX: 0000000000000200 RSI: 0000000000000000 RDI: 0000000000000000
[  533.789922] RBP: ffffb9b708df3a48 R08: ffff940d3b3fdd20 R09: 0000000000000000
[  534.137512] R10: ffffb9b708df3958 R11: 0000000000000000 R12: 0000000000000000
[  534.485329] R13: 0000000000000000 R14: 0000000000000000 R15: ffff940d39212020
[  534.833319] FS:  00007efec26e3840(0000) GS:ffff940d1f480000(0000) knlGS:0000000000000000
[  535.224098] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  535.504318] CR2: 0000000000000008 CR3: 0000001f4e256004 CR4: 00000000001606e0
[  535.851759] Call Trace:
[  535.970308]  ? mempool_alloc_slab+0x15/0x20
[  536.174152]  ? bch_data_insert+0x42/0xd0 [bcache]
[  536.403399]  blk_mq_make_request+0x97/0x4f0
[  536.607036]  generic_make_request+0x1e2/0x410
[  536.819164]  submit_bio+0x73/0x150
[  536.980168]  ? submit_bio+0x73/0x150
[  537.149731]  ? bio_associate_blkg_from_css+0x3b/0x60
[  537.391595]  ? _cond_resched+0x1a/0x50
[  537.573774]  submit_bio_wait+0x59/0x90
[  537.756105]  blkdev_issue_discard+0x80/0xd0
[  537.959590]  ext4_trim_fs+0x4a9/0x9e0
[  538.137636]  ? ext4_trim_fs+0x4a9/0x9e0
[  538.324087]  ext4_ioctl+0xea4/0x1530
[  538.497712]  ? _copy_to_user+0x2a/0x40
[  538.679632]  do_vfs_ioctl+0xa6/0x600
[  538.853127]  ? __do_sys_newfstat+0x44/0x70
[  539.051951]  ksys_ioctl+0x6d/0x80
[  539.212785]  __x64_sys_ioctl+0x1a/0x20
[  539.394918]  do_syscall_64+0x5a/0x110
[  539.568674]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

We have observed it where both:
1) LVM/devmapper is involved (bcache backing device is LVM volume) and
2) writeback cache is involved (bcache cache_mode is writeback)

On one machine, we can reliably reproduce it with:

 # echo writeback > /sys/block/bcache0/bcache/cache_mode
   (not sure whether above line is required)
 # mount /dev/bcache0 /test
 # for i in {0..10}; do
	file="$(mktemp /test/zero.XXX)"
	dd if=/dev/zero of="$file" bs=1M count=256
	sync
	rm $file
    done
  # fstrim -v /test

Observing this with tracepoints on, we see the following writes:

fstrim-18019 [022] .... 91107.302026: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 4260112 + 196352 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302050: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 4456464 + 262144 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302075: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 4718608 + 81920 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302094: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 5324816 + 180224 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302121: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 5505040 + 262144 hit 0 bypass 1
fstrim-18019 [022] .... 91107.302145: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 5767184 + 81920 hit 0 bypass 1
fstrim-18019 [022] .... 91107.308777: bcache_write: 73f95583-561c-408f-a93a-4cbd2498f5c8 inode 0  DS 6373392 + 180224 hit 1 bypass 0
<crash>

Note the final one has different hit/bypass flags.

This is because in should_writeback(), we were hitting a case where
the partial stripe condition was returning true and so
should_writeback() was returning true early.

If that hadn't been the case, it would have hit the would_skip test, and
as would_skip == s->iop.bypass == true, should_writeback() would have
returned false.

Looking at the git history from 'commit 72c2706 ("bcache: Write out
full stripes")', it looks like the idea was to optimise for raid5/6:

       * If a stripe is already dirty, force writes to that stripe to
	 writeback mode - to help build up full stripes of dirty data

To fix this issue, make sure that should_writeback() on a discard op
never returns true.

More details of debugging:
https://www.spinics.net/lists/linux-bcache/msg06996.html

Previous reports:
 - https://bugzilla.kernel.org/show_bug.cgi?id=201051
 - https://bugzilla.kernel.org/show_bug.cgi?id=196103
 - https://www.spinics.net/lists/linux-bcache/msg06885.html

(Coly Li: minor modification to follow maximum 75 chars per line rule)

Cc: Kent Overstreet <koverstreet@google.com>
Cc: stable@vger.kernel.org
Fixes: 72c2706 ("bcache: Write out full stripes")
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
…FCP devices

commit 242ec14 upstream.

Suppose more than one non-NPIV FCP device is active on the same channel.
Send I/O to storage and have some of the pending I/O run into a SCSI
command timeout, e.g. due to bit errors on the fibre. Now the error
situation stops. However, we saw FCP requests continue to timeout in the
channel. The abort will be successful, but the subsequent TUR fails.
Scsi_eh starts. The LUN reset fails. The target reset fails.  The host
reset only did an FCP device recovery. However, for non-NPIV FCP devices,
this does not close and reopen ports on the SAN-side if other non-NPIV FCP
device(s) share the same open ports.

In order to resolve the continuing FCP request timeouts, we need to
explicitly close and reopen ports on the SAN-side.

This was missing since the beginning of zfcp in v2.6.0 history commit
ea127f9 ("[PATCH] s390 (7/7): zfcp host adapter.").

Note: The FSF requests for forced port reopen could run into FSF request
timeouts due to other reasons. This would trigger an internal FCP device
recovery. Pending forced port reopen recoveries would get dismissed. So
some ports might not get fully reopened during this host reset handler.
However, subsequent I/O would trigger the above described escalation and
eventually all ports would be forced reopen to resolve any continuing FCP
request timeouts due to earlier bit errors.

Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 1da177e ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org> #3.0+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
commit 23da958 upstream.

Syzkaller reports:

kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN PTI
CPU: 1 PID: 5373 Comm: syz-executor.0 Not tainted 5.0.0-rc8+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:put_links+0x101/0x440 fs/proc/proc_sysctl.c:1599
Code: 00 0f 85 3a 03 00 00 48 8b 43 38 48 89 44 24 20 48 83 c0 38 48 89 c2 48 89 44 24 28 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 fe 02 00 00 48 8b 74 24 20 48 c7 c7 60 2a 9d 91
RSP: 0018:ffff8881d828f238 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8881e01b1140 RCX: ffffffff8ee98267
RDX: 0000000000000007 RSI: ffffc90001479000 RDI: ffff8881e01b1178
RBP: dffffc0000000000 R08: ffffed103ee27259 R09: ffffed103ee27259
R10: 0000000000000001 R11: ffffed103ee27258 R12: fffffffffffffff4
R13: 0000000000000006 R14: ffff8881f59838c0 R15: dffffc0000000000
FS:  00007f072254f700(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff8b286668 CR3: 00000001f0542002 CR4: 00000000007606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 drop_sysctl_table+0x152/0x9f0 fs/proc/proc_sysctl.c:1629
 get_subdir fs/proc/proc_sysctl.c:1022 [inline]
 __register_sysctl_table+0xd65/0x1090 fs/proc/proc_sysctl.c:1335
 br_netfilter_init+0xbc/0x1000 [br_netfilter]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f072254ec58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 00007f072254ec70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f072254f6bc
R13: 00000000004bcefa R14: 00000000006f6fb0 R15: 0000000000000004
Modules linked in: br_netfilter(+) dvb_usb_dibusb_mc_common dib3000mc dibx000_common dvb_usb_dibusb_common dvb_usb_dw2102 dvb_usb classmate_laptop palmas_regulator cn videobuf2_v4l2 v4l2_common snd_soc_bd28623 mptbase snd_usb_usx2y snd_usbmidi_lib snd_rawmidi wmi libnvdimm lockd sunrpc grace rc_kworld_pc150u rc_core rtc_da9063 sha1_ssse3 i2c_cros_ec_tunnel adxl34x_spi adxl34x nfnetlink lib80211 i5500_temp dvb_as102 dvb_core videobuf2_common videodev media videobuf2_vmalloc videobuf2_memops udc_core lnbp22 leds_lp3952 hid_roccat_ryos s1d13xxxfb mtd vport_geneve openvswitch nf_conncount nf_nat_ipv6 nsh geneve udp_tunnel ip6_udp_tunnel snd_soc_mt6351 sis_agp phylink snd_soc_adau1761_spi snd_soc_adau1761 snd_soc_adau17x1 snd_soc_core snd_pcm_dmaengine ac97_bus snd_compress snd_soc_adau_utils snd_soc_sigmadsp_regmap snd_soc_sigmadsp raid_class hid_roccat_konepure hid_roccat_common hid_roccat c2port_duramar2150 core mdio_bcm_unimac iptable_security iptable_raw iptable_mangle
 iptable_nat nf_nat_ipv4 nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bpfilter ip6_vti ip_vti ip_gre ipip sit tunnel4 ip_tunnel hsr veth netdevsim devlink vxcan batman_adv cfg80211 rfkill chnl_net caif nlmon dummy team bonding vcan bridge stp llc ip6_gre gre ip6_tunnel tunnel6 tun crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel joydev mousedev ide_pci_generic piix aesni_intel aes_x86_64 ide_core crypto_simd atkbd cryptd glue_helper serio_raw ata_generic pata_acpi i2c_piix4 floppy sch_fq_codel ip_tables x_tables ipv6 [last unloaded: lm73]
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace 770020de38961fd0 ]---

A new dir entry can be created in get_subdir and its 'header->parent' is
set to NULL.  Only after insert_header success, it will be set to 'dir',
otherwise 'header->parent' is set to NULL and drop_sysctl_table is called.
However in err handling path of get_subdir, drop_sysctl_table also be
called on 'new->header' regardless its value of parent pointer.  Then
put_links is called, which triggers NULL-ptr deref when access member of
header->parent.

In fact we have multiple error paths which call drop_sysctl_table() there,
upon failure on insert_links() we also call drop_sysctl_table().And even
in the successful case on __register_sysctl_table() we still always call
drop_sysctl_table().This patch fix it.

Link: http://lkml.kernel.org/r/20190314085527.13244-1-yuehaibing@huawei.com
Fixes: 0e47c99 ("sysctl: Replace root_list with links between sysctl_table_sets")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reported-by: Hulk Robot <hulkci@huawei.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>    [3.4+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
[ Upstream commit aadcef6 ]

As Jiqun Li reported in bugzilla:

https://bugzilla.kernel.org/show_bug.cgi?id=202883

sometimes, dead lock when make system call SYS_getdents64 with fsync() is
called by another process.

monkey running on android9.0

1.  task 9785 held sbi->cp_rwsem and waiting lock_page()
2.  task 10349 held mm_sem and waiting sbi->cp_rwsem
3. task 9709 held lock_page() and waiting mm_sem

so this is a dead lock scenario.

task stack is show by crash tools as following

crash_arm64> bt ffffffc03c354080
PID: 9785   TASK: ffffffc03c354080  CPU: 1   COMMAND: "RxIoScheduler-3"
>> #7 [ffffffc01b50fac0] __lock_page at ffffff80081b11e8

crash-arm64> bt 10349
PID: 10349  TASK: ffffffc018b83080  CPU: 1   COMMAND: "BUGLY_ASYNC_UPL"
>> #3 [ffffffc01f8cfa40] rwsem_down_read_failed at ffffff8008a93afc
     PC: 00000033  LR: 00000000  SP: 00000000  PSTATE: ffffffffffffffff

crash-arm64> bt 9709
PID: 9709   TASK: ffffffc03e7f3080  CPU: 1   COMMAND: "IntentService[A"
>> #3 [ffffffc001e67850] rwsem_down_read_failed at ffffff8008a93afc
>> #8 [ffffffc001e67b80] el1_ia at ffffff8008084fc4
     PC: ffffff8008274114  [compat_filldir64+120]
     LR: ffffff80083584d4  [f2fs_fill_dentries+448]
     SP: ffffffc001e67b80  PSTATE: 80400145
    X29: ffffffc001e67b80  X28: 0000000000000000  X27: 000000000000001a
    X26: 00000000000093d7  X25: ffffffc070d52480  X24: 0000000000000008
    X23: 0000000000000028  X22: 00000000d43dfd60  X21: ffffffc001e67e90
    X20: 0000000000000011  X19: ffffff80093a4000  X18: 0000000000000000
    X17: 0000000000000000  X16: 0000000000000000  X15: 0000000000000000
    X14: ffffffffffffffff  X13: 0000000000000008  X12: 0101010101010101
    X11: 7f7f7f7f7f7f7f7f  X10: 6a6a6a6a6a6a6a6a   X9: 7f7f7f7f7f7f7f7f
     X8: 0000000080808000   X7: ffffff800827409c   X6: 0000000080808000
     X5: 0000000000000008   X4: 00000000000093d7   X3: 000000000000001a
     X2: 0000000000000011   X1: ffffffc070d52480   X0: 0000000000800238
>> #9 [ffffffc001e67be0] f2fs_fill_dentries at ffffff80083584d0
     PC: 0000003c  LR: 00000000  SP: 00000000  PSTATE: 000000d9
    X12: f48a02ff X11: d4678960 X10: d43dfc00  X9: d4678ae4
     X8: 00000058  X7: d4678994  X6: d43de800  X5: 000000d9
     X4: d43dfc0c  X3: d43dfc10  X2: d46799c8  X1: 00000000
     X0: 00001068

Below potential deadlock will happen between three threads:
Thread A		Thread B		Thread C
- f2fs_do_sync_file
 - f2fs_write_checkpoint
  - down_write(&sbi->node_change) -- 1)
			- do_page_fault
			 - down_write(&mm->mmap_sem) -- 2)
			  - do_wp_page
			   - f2fs_vm_page_mkwrite
						- getdents64
						 - f2fs_read_inline_dir
						  - lock_page -- 3)
  - f2fs_sync_node_pages
   - lock_page -- 3)
			    - __do_map_lock
			     - down_read(&sbi->node_change) -- 1)
						  - f2fs_fill_dentries
						   - dir_emit
						    - compat_filldir64
						     - do_page_fault
						      - down_read(&mm->mmap_sem) -- 2)

Since f2fs_readdir is protected by inode.i_rwsem, there should not be
any updates in inode page, we're safe to lookup dents in inode page
without its lock held, so taking off the lock to improve concurrency
of readdir and avoid potential deadlock.

Reported-by: Jiqun Li <jiqun.li@unisoc.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
…sion logic

[ Upstream commit c3b81a5 ]

When the prefix suppresion/enabling logic was added, I forgot to add an
extra %, which ended up chopping off the strings:

Before:

  # perf trace -e *mmsg --map-dump syscalls
  [299] = 1,
  [307] = 1,
  DNS Res~ver #3/14587 sendmmsg(106<socket:[3462393]>, 0x7f252b0fcaf0, 2, MSG_) = 2
  chronyd/1053 recvmmsg(4, 0x558542ca5740, 4, MSG_, NULL) = 1
  DNS Res~ver #2/14445 sendmmsg(106<socket:[3461475]>, 0x7f252ab09af0, 2, MSG_) = 2
  DNS Res~ver #2/14444 sendmmsg(146<socket:[3457863]>, 0x7f2521a7aaf0, 2, MSG_) = 2
  DNS Res~ver #2/14445 sendmmsg(106<socket:[3461475]>, 0x7f252ab09af0, 2, MSG_) = 2
  DNS Res~ver #3/14587 sendmmsg(148<socket:[3460636]>, 0x7f252b0fcaf0, 2, MSG_) = 2
  DNS Res~ver #2/14444 sendmmsg(146<socket:[3457863]>, 0x7f2521a7aaf0, 2, MSG_) = 2
  ^C#

After:

  # perf trace -e *mmsg --map-dump syscalls
  [299] = 1,
  [307] = 1,
  NetworkManager/17467 sendmmsg(22<socket:[3466493]>, 0x7f28927f9bb0, 2, MSG_NOSIGNAL) = 2
  pool/17478 sendmmsg(10<socket:[3466523]>, 0x7f2769f95e90, 2, MSG_NOSIGNAL) = 2
  DNS Res~ver #3/14587 sendmmsg(121<socket:[3466132]>, 0x7f252b0fcaf0, 2, MSG_NOSIGNAL) = 2
  chronyd/1053 recvmmsg(4, 0x558542ca5740, 4, MSG_DONTWAIT, NULL) = 1
  Socket Thread/17433 sendmmsg(121<socket:[3460903]>, 0x7f252668baf0, 2, MSG_NOSIGNAL) = 2
  ^C#

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: c65c83f ("perf trace: Allow asking for not suppressing common string prefixes")
Link: https://lkml.kernel.org/n/tip-t2eu1rqx710k6jr4814mlzg7@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
[ Upstream commit 0510748 ]

We were crashing when processing a negative fd:

  Program received signal SIGSEGV, Segmentation fault.
  0x0000000000609bbf in syscall_arg__scnprintf_ioctl_cmd (bf=0x1172eca "", size=2038, arg=0x7fffffff8360) at trace/beauty/ioctl.c:182
  182			if (file->dev_maj == USB_DEVICE_MAJOR)
  Missing separate debuginfos, use: dnf debuginfo-install bzip2-libs-1.0.6-28.fc29.x86_64 elfutils-libelf-0.174-5.fc29.x86_64 elfutils-libs-0.174-5.fc29.x86_64 glib2-2.58.3-1.fc29.x86_64 libbabeltrace-1.5.6-1.fc29.x86_64 libunwind-1.2.1-6.fc29.x86_64 libuuid-2.32.1-1.fc29.x86_64 libxcrypt-4.4.3-2.fc29.x86_64 numactl-libs-2.0.12-1.fc29.x86_64 openssl-libs-1.1.1a-1.fc29.x86_64 pcre-8.42-6.fc29.x86_64 perl-libs-5.28.1-427.fc29.x86_64 popt-1.16-15.fc29.x86_64 python2-libs-2.7.15-11.fc29.x86_64 slang-2.3.2-4.fc29.x86_64 xz-libs-5.2.4-3.fc29.x86_64
  (gdb) bt
  #0  0x0000000000609bbf in syscall_arg__scnprintf_ioctl_cmd (bf=0x1172eca "", size=2038, arg=0x7fffffff8360) at trace/beauty/ioctl.c:182
  #1  0x000000000048e295 in syscall__scnprintf_val (sc=0x123b500, bf=0x1172eca "", size=2038, arg=0x7fffffff8360, val=21519)
      at builtin-trace.c:1594
  #2  0x000000000048e60d in syscall__scnprintf_args (sc=0x123b500, bf=0x1172ec6 "-1, ", size=2042, args=0x7ffff6a7c034 "\377\377\377\377",
      augmented_args=0x7ffff6a7c064, augmented_args_size=4, trace=0x7fffffffa8d0, thread=0x1175cd0) at builtin-trace.c:1661
  #3  0x000000000048f04e in trace__sys_enter (trace=0x7fffffffa8d0, evsel=0xb260b0, event=0x7ffff6a7bfe8, sample=0x7fffffff84f0)
      at builtin-trace.c:1880
  #4  0x00000000004915a4 in trace__handle_event (trace=0x7fffffffa8d0, event=0x7ffff6a7bfe8, sample=0x7fffffff84f0) at builtin-trace.c:2590
  #5  0x0000000000491eed in __trace__deliver_event (trace=0x7fffffffa8d0, event=0x7ffff6a7bfe8) at builtin-trace.c:2818
  #6  0x0000000000492030 in trace__deliver_event (trace=0x7fffffffa8d0, event=0x7ffff6a7bfe8) at builtin-trace.c:2845
  #7  0x0000000000492896 in trace__run (trace=0x7fffffffa8d0, argc=0, argv=0x7fffffffdb58) at builtin-trace.c:3040
  #8  0x000000000049603a in cmd_trace (argc=0, argv=0x7fffffffdb58) at builtin-trace.c:3952
  #9  0x00000000004d5103 in main (argc=1, argv=0x7fffffffdb58) at perf.c:474
  (gdb) p fd
  $1 = -1
  (gdb) p file
  $7 = (struct file *) 0xfffffffffffffff0
  (gdb) p ((struct thread_trace *)arg->thread)->files.table + fd
  $8 = (struct file *) 0xfffffffffffffff0
  (gdb)

Check for that and return NULL instead.

This problem was introduced recently, the other codepaths leading to
thread_trace__files_entry() check for negative fds, like thread__fd_path(),
but we need to do it at thread_trace__files_entry() as more users are now
calling it directly.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Fixes: 2d47338 ("perf trace beauty: Export function to get the files for a thread")
Link: https://lkml.kernel.org/n/tip-oq7bvaaf07gsd4yqty3107u2@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 19, 2019
[ Upstream commit 2ec1ed2 ]

When a bpf program is uploaded, the driver computes the number of
xdp tx queues resulting in the allocation of additional qsets.
Starting from commit '2ecbe4f4a027 ("net: thunderx: replace global
nicvf_rx_mode_wq work queue for all VFs to private for each of them")'
the driver runs link state polling for each VF resulting in the
following NULL pointer dereference:

[   56.169256] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000020
[   56.178032] Mem abort info:
[   56.180834]   ESR = 0x96000005
[   56.183877]   Exception class = DABT (current EL), IL = 32 bits
[   56.189792]   SET = 0, FnV = 0
[   56.192834]   EA = 0, S1PTW = 0
[   56.195963] Data abort info:
[   56.198831]   ISV = 0, ISS = 0x00000005
[   56.202662]   CM = 0, WnR = 0
[   56.205619] user pgtable: 64k pages, 48-bit VAs, pgdp = 0000000021f0c7a0
[   56.212315] [0000000000000020] pgd=0000000000000000, pud=0000000000000000
[   56.219094] Internal error: Oops: 96000005 [#1] SMP
[   56.260459] CPU: 39 PID: 2034 Comm: ip Not tainted 5.1.0-rc3+ #3
[   56.266452] Hardware name: GIGABYTE R120-T33/MT30-GS1, BIOS T49 02/02/2018
[   56.273315] pstate: 80000005 (Nzcv daif -PAN -UAO)
[   56.278098] pc : __ll_sc___cmpxchg_case_acq_64+0x4/0x20
[   56.283312] lr : mutex_lock+0x2c/0x50
[   56.286962] sp : ffff0000219af1b0
[   56.290264] x29: ffff0000219af1b0 x28: ffff800f64de49a0
[   56.295565] x27: 0000000000000000 x26: 0000000000000015
[   56.300865] x25: 0000000000000000 x24: 0000000000000000
[   56.306165] x23: 0000000000000000 x22: ffff000011117000
[   56.311465] x21: ffff800f64dfc080 x20: 0000000000000020
[   56.316766] x19: 0000000000000020 x18: 0000000000000001
[   56.322066] x17: 0000000000000000 x16: ffff800f2e077080
[   56.327367] x15: 0000000000000004 x14: 0000000000000000
[   56.332667] x13: ffff000010964438 x12: 0000000000000002
[   56.337967] x11: 0000000000000000 x10: 0000000000000c70
[   56.343268] x9 : ffff0000219af120 x8 : ffff800f2e077d50
[   56.348568] x7 : 0000000000000027 x6 : 000000062a9d6a84
[   56.353869] x5 : 0000000000000000 x4 : ffff800f2e077480
[   56.359169] x3 : 0000000000000008 x2 : ffff800f2e077080
[   56.364469] x1 : 0000000000000000 x0 : 0000000000000020
[   56.369770] Process ip (pid: 2034, stack limit = 0x00000000c862da3a)
[   56.376110] Call trace:
[   56.378546]  __ll_sc___cmpxchg_case_acq_64+0x4/0x20
[   56.383414]  drain_workqueue+0x34/0x198
[   56.387247]  nicvf_open+0x48/0x9e8 [nicvf]
[   56.391334]  nicvf_open+0x898/0x9e8 [nicvf]
[   56.395507]  nicvf_xdp+0x1bc/0x238 [nicvf]
[   56.399595]  dev_xdp_install+0x68/0x90
[   56.403333]  dev_change_xdp_fd+0xc8/0x240
[   56.407333]  do_setlink+0x8e0/0xbe8
[   56.410810]  __rtnl_newlink+0x5b8/0x6d8
[   56.414634]  rtnl_newlink+0x54/0x80
[   56.418112]  rtnetlink_rcv_msg+0x22c/0x2f8
[   56.422199]  netlink_rcv_skb+0x60/0x120
[   56.426023]  rtnetlink_rcv+0x28/0x38
[   56.429587]  netlink_unicast+0x1c8/0x258
[   56.433498]  netlink_sendmsg+0x1b4/0x350
[   56.437410]  sock_sendmsg+0x4c/0x68
[   56.440887]  ___sys_sendmsg+0x240/0x280
[   56.444711]  __sys_sendmsg+0x68/0xb0
[   56.448275]  __arm64_sys_sendmsg+0x2c/0x38
[   56.452361]  el0_svc_handler+0x9c/0x128
[   56.456186]  el0_svc+0x8/0xc
[   56.459056] Code: 35ffff91 2a1003e0 d65f03c0 f9800011 (c85ffc10)
[   56.465166] ---[ end trace 4a57fdc27b0a572c ]---
[   56.469772] Kernel panic - not syncing: Fatal exception

Fix it by checking nicvf_rx_mode_wq pointer in nicvf_open and nicvf_stop

Fixes: 2ecbe4f ("net: thunderx: replace global nicvf_rx_mode_wq work queue for all VFs to private for each of them")
Fixes: 2c632ad ("net: thunderx: move link state polling function to VF")
Reported-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Tested-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
…_map

[ Upstream commit 39df730 ]

Detected via gcc's ASan:

  Direct leak of 2048 byte(s) in 64 object(s) allocated from:
    6     #0 0x7f606512e370 in __interceptor_realloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee370)
    7     #1 0x556b0f1d7ddd in thread_map__realloc util/thread_map.c:43
    8     #2 0x556b0f1d84c7 in thread_map__new_by_tid util/thread_map.c:85
    9     #3 0x556b0f0e045e in is_event_supported util/parse-events.c:2250
   10     #4 0x556b0f0e1aa1 in print_hwcache_events util/parse-events.c:2382
   11     #5 0x556b0f0e3231 in print_events util/parse-events.c:2514
   12     #6 0x556b0ee0a66e in cmd_list /home/changbin/work/linux/tools/perf/builtin-list.c:58
   13     #7 0x556b0f01e0ae in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
   14     #8 0x556b0f01e859 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
   15     #9 0x556b0f01edc8 in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
   16     #10 0x556b0f01f71f in main /home/changbin/work/linux/tools/perf/perf.c:520
   17     #11 0x7f6062ccf09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 8989605 ("perf tools: Do not put a variable sized type not at the end of a struct")
Link: http://lkml.kernel.org/r/20190316080556.3075-3-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
[ Upstream commit 54569ba ]

Detected with gcc's ASan:

  Direct leak of 66 byte(s) in 5 object(s) allocated from:
      #0 0x7ff3b1f32070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
      #1 0x560c8761034d in collect_config util/config.c:597
      #2 0x560c8760d9cb in get_value util/config.c:169
      #3 0x560c8760dfd7 in perf_parse_file util/config.c:285
      #4 0x560c8760e0d2 in perf_config_from_file util/config.c:476
      #5 0x560c876108fd in perf_config_set__init util/config.c:661
      #6 0x560c87610c72 in perf_config_set__new util/config.c:709
      #7 0x560c87610d2f in perf_config__init util/config.c:718
      #8 0x560c87610e5d in perf_config util/config.c:730
      #9 0x560c875ddea0 in main /home/changbin/work/linux/tools/perf/perf.c:442
      #10 0x7ff3afb8609a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Fixes: 20105ca ("perf config: Introduce perf_config_set class")
Link: http://lkml.kernel.org/r/20190316080556.3075-6-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
[ Upstream commit 8bde851 ]

Detected with gcc's ASan:

  Direct leak of 4356 byte(s) in 120 object(s) allocated from:
      #0 0x7ff1a2b5a070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
      #1 0x55719aef4814 in build_id_cache__origname util/build-id.c:215
      #2 0x55719af649b6 in print_sdt_events util/parse-events.c:2339
      #3 0x55719af66272 in print_events util/parse-events.c:2542
      #4 0x55719ad1ecaa in cmd_list /home/changbin/work/linux/tools/perf/builtin-list.c:58
      #5 0x55719aec745d in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #6 0x55719aec7d1a in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #7 0x55719aec8184 in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #8 0x55719aeca41a in main /home/changbin/work/linux/tools/perf/perf.c:520
      #9 0x7ff1a07ae09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 40218da ("perf list: Show SDT and pre-cached events")
Link: http://lkml.kernel.org/r/20190316080556.3075-7-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
[ Upstream commit 1e5b0cf ]

The array str[] should have six elements.

  =================================================================
  ==4322==ERROR: AddressSanitizer: global-buffer-overflow on address 0x56463844e300 at pc 0x564637e7ad0d bp 0x7f30c8c89d10 sp 0x7f30c8c89d00
  READ of size 8 at 0x56463844e300 thread T9
      #0 0x564637e7ad0c in __ordered_events__flush util/ordered-events.c:316
      #1 0x564637e7b0e4 in ordered_events__flush util/ordered-events.c:338
      #2 0x564637c6a57d in process_thread /home/changbin/work/linux/tools/perf/builtin-top.c:1073
      #3 0x7f30d173a163 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x8163)
      #4 0x7f30cfffbdee in __clone (/lib/x86_64-linux-gnu/libc.so.6+0x11adee)

  0x56463844e300 is located 32 bytes to the left of global variable 'flags' defined in 'util/trace-event-parse.c:229:26' (0x56463844e320) of size 192
  0x56463844e300 is located 0 bytes to the right of global variable 'str' defined in 'util/ordered-events.c:268:28' (0x56463844e2e0) of size 32
  SUMMARY: AddressSanitizer: global-buffer-overflow util/ordered-events.c:316 in __ordered_events__flush
  Shadow bytes around the buggy address:
    0x0ac947081c10: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081c20: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081c30: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081c40: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081c50: 00 00 00 00 00 00 00 00 f9 f9 f9 f9 00 00 00 00
  =>0x0ac947081c60:[f9]f9 f9 f9 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081c70: 00 00 00 00 00 00 00 00 00 00 00 00 f9 f9 f9 f9
    0x0ac947081c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081c90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081ca0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    0x0ac947081cb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  Shadow byte legend (one shadow byte represents 8 application bytes):
    Addressable:           00
    Partially addressable: 01 02 03 04 05 06 07
    Heap left redzone:       fa
    Freed heap region:       fd
    Stack left redzone:      f1
    Stack mid redzone:       f2
    Stack right redzone:     f3
    Stack after return:      f5
    Stack use after scope:   f8
    Global redzone:          f9
    Global init order:       f6
    Poisoned by user:        f7
    Container overflow:      fc
    Array cookie:            ac
    Intra object redzone:    bb
    ASan internal:           fe
    Left alloca redzone:     ca
    Right alloca redzone:    cb
  Thread T9 created by T0 here:
      #0 0x7f30d179de5f in __interceptor_pthread_create (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x4ae5f)
      #1 0x564637c6b954 in __cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1253
      #2 0x564637c7173c in cmd_top /home/changbin/work/linux/tools/perf/builtin-top.c:1642
      #3 0x564637d85038 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #4 0x564637d85577 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #5 0x564637d8597b in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #6 0x564637d860e9 in main /home/changbin/work/linux/tools/perf/perf.c:520
      #7 0x7f30cff0509a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Fixes: 16c66bc ("perf top: Add processing thread")
Fixes: 68ca5d0 ("perf ordered_events: Add ordered_events__flush_time interface")
Link: http://lkml.kernel.org/r/20190316080556.3075-13-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
[ Upstream commit 42dfa45 ]

Using gcc's ASan, Changbin reports:

  =================================================================
  ==7494==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 48 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      #1 0x5625e5330a5e in zalloc util/util.h:23
      #2 0x5625e5330a9b in perf_counts__new util/counts.c:10
      #3 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47
      #4 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505
      #5 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347
      #6 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47
      #7 0x5625e51528e6 in run_test tests/builtin-test.c:358
      #8 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      #9 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      #10 0x5625e515572f in cmd_test tests/builtin-test.c:722
      #11 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #12 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #13 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #14 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      #15 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  Indirect leak of 72 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      #1 0x5625e532560d in zalloc util/util.h:23
      #2 0x5625e532566b in xyarray__new util/xyarray.c:10
      #3 0x5625e5330aba in perf_counts__new util/counts.c:15
      #4 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47
      #5 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505
      #6 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347
      #7 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47
      #8 0x5625e51528e6 in run_test tests/builtin-test.c:358
      #9 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      #10 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      #11 0x5625e515572f in cmd_test tests/builtin-test.c:722
      #12 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #13 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #14 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #15 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      #16 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

His patch took care of evsel->prev_raw_counts, but the above backtraces
are about evsel->counts, so fix that instead.

Reported-by: Changbin Du <changbin.du@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/n/tip-hd1x13g59f0nuhe4anxhsmfp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
…_event_on_all_cpus test

[ Upstream commit 93faa52 ]

  =================================================================
  ==7497==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 40 byte(s) in 1 object(s) allocated from:
      #0 0x7f0333a88f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
      #1 0x5625e5326213 in cpu_map__trim_new util/cpumap.c:45
      #2 0x5625e5326703 in cpu_map__read util/cpumap.c:103
      #3 0x5625e53267ef in cpu_map__read_all_cpu_map util/cpumap.c:120
      #4 0x5625e5326915 in cpu_map__new util/cpumap.c:135
      #5 0x5625e517b355 in test__openat_syscall_event_on_all_cpus tests/openat-syscall-all-cpus.c:36
      #6 0x5625e51528e6 in run_test tests/builtin-test.c:358
      #7 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      #8 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      #9 0x5625e515572f in cmd_test tests/builtin-test.c:722
      #10 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #11 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #12 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #13 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      #14 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: f30a79b ("perf tools: Add reference counting for cpu_map object")
Link: http://lkml.kernel.org/r/20190316080556.3075-15-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
[ Upstream commit f97a899 ]

  =================================================================
  ==7506==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 13 byte(s) in 3 object(s) allocated from:
      #0 0x7f03339d6070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
      #1 0x5625e53aaef0 in expr__find_other util/expr.y:221
      #2 0x5625e51bcd3f in test__expr tests/expr.c:52
      #3 0x5625e51528e6 in run_test tests/builtin-test.c:358
      #4 0x5625e5152baf in test_and_print tests/builtin-test.c:388
      #5 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
      #6 0x5625e515572f in cmd_test tests/builtin-test.c:722
      #7 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #8 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #9 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #10 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
      #11 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 0751673 ("perf tools: Add a simple expression parser for JSON")
Link: http://lkml.kernel.org/r/20190316080556.3075-16-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Apr 28, 2019
[ Upstream commit d982b33 ]

  =================================================================
  ==20875==ERROR: LeakSanitizer: detected memory leaks

  Direct leak of 1160 byte(s) in 1 object(s) allocated from:
      #0 0x7f1b6fc84138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
      #1 0x55bd50005599 in zalloc util/util.h:23
      #2 0x55bd500068f5 in perf_evsel__newtp_idx util/evsel.c:327
      #3 0x55bd4ff810fc in perf_evsel__newtp /home/work/linux/tools/perf/util/evsel.h:216
      #4 0x55bd4ff81608 in test__perf_evsel__tp_sched_test tests/evsel-tp-sched.c:69
      #5 0x55bd4ff528e6 in run_test tests/builtin-test.c:358
      #6 0x55bd4ff52baf in test_and_print tests/builtin-test.c:388
      #7 0x55bd4ff543fe in __cmd_test tests/builtin-test.c:583
      #8 0x55bd4ff5572f in cmd_test tests/builtin-test.c:722
      #9 0x55bd4ffc4087 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
      #10 0x55bd4ffc45c6 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
      #11 0x55bd4ffc49ca in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
      #12 0x55bd4ffc5138 in main /home/changbin/work/linux/tools/perf/perf.c:520
      #13 0x7f1b6e34809a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)

  Indirect leak of 19 byte(s) in 1 object(s) allocated from:
      #0 0x7f1b6fc83f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
      #1 0x7f1b6e3ac30f in vasprintf (/lib/x86_64-linux-gnu/libc.so.6+0x8830f)

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 6a6cd11 ("perf test: Add test for the sched tracepoint format fields")
Link: http://lkml.kernel.org/r/20190316080556.3075-17-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue May 10, 2019
commit 08b7c2f upstream.

If `vmk80xx_auto_attach()` returns an error, the core comedi module code
will call `vmk80xx_detach()` to clean up.  If `vmk80xx_auto_attach()`
successfully allocated the comedi device private data,
`vmk80xx_detach()` assumes that a `struct semaphore limit_sem` contained
in the private data has been initialized and uses it.  Unfortunately,
there are a couple of places where `vmk80xx_auto_attach()` can return an
error after allocating the device private data but before initializing
the semaphore, so this assumption is invalid.  Fix it by initializing
the semaphore just after allocating the private data in
`vmk80xx_auto_attach()` before any other errors can be returned.

I believe this was the cause of the following syzbot crash report
<https://syzkaller.appspot.com/bug?extid=54c2f58f15fe6876b6ad>:

usb 1-1: config 0 has no interface number 0
usb 1-1: New USB device found, idVendor=10cf, idProduct=8068, bcdDevice=e6.8d
usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
usb 1-1: config 0 descriptor??
vmk80xx 1-1:0.117: driver 'vmk80xx' failed to auto-configure device.
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.1.0-rc4-319354-g9a33b36 #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe8/0x16e lib/dump_stack.c:113
 assign_lock_key kernel/locking/lockdep.c:786 [inline]
 register_lock_class+0x11b8/0x1250 kernel/locking/lockdep.c:1095
 __lock_acquire+0xfb/0x37c0 kernel/locking/lockdep.c:3582
 lock_acquire+0x10d/0x2f0 kernel/locking/lockdep.c:4211
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x44/0x60 kernel/locking/spinlock.c:152
 down+0x12/0x80 kernel/locking/semaphore.c:58
 vmk80xx_detach+0x59/0x100 drivers/staging/comedi/drivers/vmk80xx.c:829
 comedi_device_detach+0xed/0x800 drivers/staging/comedi/drivers.c:204
 comedi_device_cleanup.part.0+0x68/0x140 drivers/staging/comedi/comedi_fops.c:156
 comedi_device_cleanup drivers/staging/comedi/comedi_fops.c:187 [inline]
 comedi_free_board_dev.part.0+0x16/0x90 drivers/staging/comedi/comedi_fops.c:190
 comedi_free_board_dev drivers/staging/comedi/comedi_fops.c:189 [inline]
 comedi_release_hardware_device+0x111/0x140 drivers/staging/comedi/comedi_fops.c:2880
 comedi_auto_config.cold+0x124/0x1b0 drivers/staging/comedi/drivers.c:1068
 usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
 really_probe+0x2da/0xb10 drivers/base/dd.c:509
 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
 __device_attach+0x223/0x3a0 drivers/base/dd.c:844
 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
 device_add+0xad2/0x16e0 drivers/base/core.c:2106
 usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021
 generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
 usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
 really_probe+0x2da/0xb10 drivers/base/dd.c:509
 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
 __device_attach+0x223/0x3a0 drivers/base/dd.c:844
 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
 device_add+0xad2/0x16e0 drivers/base/core.c:2106
 usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432
 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
 kthread+0x313/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Reported-by: syzbot+54c2f58f15fe6876b6ad@syzkaller.appspotmail.com
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue May 10, 2019
commit 660cf4c upstream.

If `ni6501_auto_attach()` returns an error, the core comedi module code
will call `ni6501_detach()` to clean up.  If `ni6501_auto_attach()`
successfully allocated the comedi device private data, `ni6501_detach()`
assumes that a `struct mutex mut` contained in the private data has been
initialized and uses it.  Unfortunately, there are a couple of places
where `ni6501_auto_attach()` can return an error after allocating the
device private data but before initializing the mutex, so this
assumption is invalid.  Fix it by initializing the mutex just after
allocating the private data in `ni6501_auto_attach()` before any other
errors can be retturned.  Also move the call to `usb_set_intfdata()`
just to keep the code a bit neater (either position for the call is
fine).

I believe this was the cause of the following syzbot crash report
<https://syzkaller.appspot.com/bug?extid=cf4f2b6c24aff0a3edf6>:

usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
usb 1-1: config 0 descriptor??
usb 1-1: string descriptor 0 read error: -71
comedi comedi0: Wrong number of endpoints
ni6501 1-1:0.233: driver 'ni6501' failed to auto-configure device.
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 0 PID: 585 Comm: kworker/0:3 Not tainted 5.1.0-rc4-319354-g9a33b36 #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: usb_hub_wq hub_event
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xe8/0x16e lib/dump_stack.c:113
 assign_lock_key kernel/locking/lockdep.c:786 [inline]
 register_lock_class+0x11b8/0x1250 kernel/locking/lockdep.c:1095
 __lock_acquire+0xfb/0x37c0 kernel/locking/lockdep.c:3582
 lock_acquire+0x10d/0x2f0 kernel/locking/lockdep.c:4211
 __mutex_lock_common kernel/locking/mutex.c:925 [inline]
 __mutex_lock+0xfe/0x12b0 kernel/locking/mutex.c:1072
 ni6501_detach+0x5b/0x110 drivers/staging/comedi/drivers/ni_usb6501.c:567
 comedi_device_detach+0xed/0x800 drivers/staging/comedi/drivers.c:204
 comedi_device_cleanup.part.0+0x68/0x140 drivers/staging/comedi/comedi_fops.c:156
 comedi_device_cleanup drivers/staging/comedi/comedi_fops.c:187 [inline]
 comedi_free_board_dev.part.0+0x16/0x90 drivers/staging/comedi/comedi_fops.c:190
 comedi_free_board_dev drivers/staging/comedi/comedi_fops.c:189 [inline]
 comedi_release_hardware_device+0x111/0x140 drivers/staging/comedi/comedi_fops.c:2880
 comedi_auto_config.cold+0x124/0x1b0 drivers/staging/comedi/drivers.c:1068
 usb_probe_interface+0x31d/0x820 drivers/usb/core/driver.c:361
 really_probe+0x2da/0xb10 drivers/base/dd.c:509
 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
 __device_attach+0x223/0x3a0 drivers/base/dd.c:844
 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
 device_add+0xad2/0x16e0 drivers/base/core.c:2106
 usb_set_configuration+0xdf7/0x1740 drivers/usb/core/message.c:2021
 generic_probe+0xa2/0xda drivers/usb/core/generic.c:210
 usb_probe_device+0xc0/0x150 drivers/usb/core/driver.c:266
 really_probe+0x2da/0xb10 drivers/base/dd.c:509
 driver_probe_device+0x21d/0x350 drivers/base/dd.c:671
 __device_attach_driver+0x1d8/0x290 drivers/base/dd.c:778
 bus_for_each_drv+0x163/0x1e0 drivers/base/bus.c:454
 __device_attach+0x223/0x3a0 drivers/base/dd.c:844
 bus_probe_device+0x1f1/0x2a0 drivers/base/bus.c:514
 device_add+0xad2/0x16e0 drivers/base/core.c:2106
 usb_new_device.cold+0x537/0xccf drivers/usb/core/hub.c:2534
 hub_port_connect drivers/usb/core/hub.c:5089 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5204 [inline]
 port_event drivers/usb/core/hub.c:5350 [inline]
 hub_event+0x138e/0x3b00 drivers/usb/core/hub.c:5432
 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
 kthread+0x313/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Reported-by: syzbot+cf4f2b6c24aff0a3edf6@syzkaller.appspotmail.com
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue May 10, 2019
commit bafdf85 upstream.

Move ieee80211_tx_status_ext() outside of status_list lock section
in order to avoid locking dependency and possible deadlock reposed by
LOCKDEP in below warning.

Also do mt76_tx_status_lock() just before it's needed.

[  440.224832] WARNING: possible circular locking dependency detected
[  440.224833] 5.1.0-rc2+ #22 Not tainted
[  440.224834] ------------------------------------------------------
[  440.224835] kworker/u16:28/2362 is trying to acquire lock:
[  440.224836] 0000000089b8cacf (&(&q->lock)->rlock#2){+.-.}, at: mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.224842]
               but task is already holding lock:
[  440.224842] 000000002cfedc59 (&(&sta->lock)->rlock){+.-.}, at: ieee80211_stop_tx_ba_cb+0x32/0x1f0 [mac80211]
[  440.224863]
               which lock already depends on the new lock.

[  440.224863]
               the existing dependency chain (in reverse order) is:
[  440.224864]
               -> #3 (&(&sta->lock)->rlock){+.-.}:
[  440.224869]        _raw_spin_lock_bh+0x34/0x40
[  440.224880]        ieee80211_start_tx_ba_session+0xe4/0x3d0 [mac80211]
[  440.224894]        minstrel_ht_get_rate+0x45c/0x510 [mac80211]
[  440.224906]        rate_control_get_rate+0xc1/0x140 [mac80211]
[  440.224918]        ieee80211_tx_h_rate_ctrl+0x195/0x3c0 [mac80211]
[  440.224930]        ieee80211_xmit_fast+0x26d/0xa50 [mac80211]
[  440.224942]        __ieee80211_subif_start_xmit+0xfc/0x310 [mac80211]
[  440.224954]        ieee80211_subif_start_xmit+0x38/0x390 [mac80211]
[  440.224956]        dev_hard_start_xmit+0xb8/0x300
[  440.224957]        __dev_queue_xmit+0x7d4/0xbb0
[  440.224968]        ip6_finish_output2+0x246/0x860 [ipv6]
[  440.224978]        mld_sendpack+0x1bd/0x360 [ipv6]
[  440.224987]        mld_ifc_timer_expire+0x1a4/0x2f0 [ipv6]
[  440.224989]        call_timer_fn+0x89/0x2a0
[  440.224990]        run_timer_softirq+0x1bd/0x4d0
[  440.224992]        __do_softirq+0xdb/0x47c
[  440.224994]        irq_exit+0xfa/0x100
[  440.224996]        smp_apic_timer_interrupt+0x9a/0x220
[  440.224997]        apic_timer_interrupt+0xf/0x20
[  440.224999]        cpuidle_enter_state+0xc1/0x470
[  440.225000]        do_idle+0x21a/0x260
[  440.225001]        cpu_startup_entry+0x19/0x20
[  440.225004]        start_secondary+0x135/0x170
[  440.225006]        secondary_startup_64+0xa4/0xb0
[  440.225007]
               -> #2 (&(&sta->rate_ctrl_lock)->rlock){+.-.}:
[  440.225009]        _raw_spin_lock_bh+0x34/0x40
[  440.225022]        rate_control_tx_status+0x4f/0xb0 [mac80211]
[  440.225031]        ieee80211_tx_status_ext+0x142/0x1a0 [mac80211]
[  440.225035]        mt76x02_send_tx_status+0x2e4/0x340 [mt76x02_lib]
[  440.225037]        mt76x02_tx_status_data+0x31/0x40 [mt76x02_lib]
[  440.225040]        mt76u_tx_status_data+0x51/0xa0 [mt76_usb]
[  440.225042]        process_one_work+0x237/0x5d0
[  440.225043]        worker_thread+0x3c/0x390
[  440.225045]        kthread+0x11d/0x140
[  440.225046]        ret_from_fork+0x3a/0x50
[  440.225047]
               -> #1 (&(&list->lock)->rlock#8){+.-.}:
[  440.225049]        _raw_spin_lock_bh+0x34/0x40
[  440.225052]        mt76_tx_status_skb_add+0x51/0x100 [mt76]
[  440.225054]        mt76x02u_tx_prepare_skb+0xbd/0x116 [mt76x02_usb]
[  440.225056]        mt76u_tx_queue_skb+0x5f/0x180 [mt76_usb]
[  440.225058]        mt76_tx+0x93/0x190 [mt76]
[  440.225070]        ieee80211_tx_frags+0x148/0x210 [mac80211]
[  440.225081]        __ieee80211_tx+0x75/0x1b0 [mac80211]
[  440.225092]        ieee80211_tx+0xde/0x110 [mac80211]
[  440.225105]        __ieee80211_tx_skb_tid_band+0x72/0x90 [mac80211]
[  440.225122]        ieee80211_send_auth+0x1f3/0x360 [mac80211]
[  440.225141]        ieee80211_auth.cold.40+0x6c/0x100 [mac80211]
[  440.225156]        ieee80211_mgd_auth.cold.50+0x132/0x15f [mac80211]
[  440.225171]        cfg80211_mlme_auth+0x149/0x360 [cfg80211]
[  440.225181]        nl80211_authenticate+0x273/0x2e0 [cfg80211]
[  440.225183]        genl_family_rcv_msg+0x196/0x3a0
[  440.225184]        genl_rcv_msg+0x47/0x8e
[  440.225185]        netlink_rcv_skb+0x3a/0xf0
[  440.225187]        genl_rcv+0x24/0x40
[  440.225188]        netlink_unicast+0x16d/0x210
[  440.225189]        netlink_sendmsg+0x204/0x3b0
[  440.225191]        sock_sendmsg+0x36/0x40
[  440.225193]        ___sys_sendmsg+0x259/0x2b0
[  440.225194]        __sys_sendmsg+0x47/0x80
[  440.225196]        do_syscall_64+0x60/0x1f0
[  440.225197]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  440.225198]
               -> #0 (&(&q->lock)->rlock#2){+.-.}:
[  440.225200]        lock_acquire+0xb9/0x1a0
[  440.225202]        _raw_spin_lock_bh+0x34/0x40
[  440.225204]        mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225215]        ieee80211_agg_start_txq+0xe8/0x2b0 [mac80211]
[  440.225225]        ieee80211_stop_tx_ba_cb+0xb8/0x1f0 [mac80211]
[  440.225235]        ieee80211_ba_session_work+0x1c1/0x2f0 [mac80211]
[  440.225236]        process_one_work+0x237/0x5d0
[  440.225237]        worker_thread+0x3c/0x390
[  440.225239]        kthread+0x11d/0x140
[  440.225240]        ret_from_fork+0x3a/0x50
[  440.225240]
               other info that might help us debug this:

[  440.225241] Chain exists of:
                 &(&q->lock)->rlock#2 --> &(&sta->rate_ctrl_lock)->rlock --> &(&sta->lock)->rlock

[  440.225243]  Possible unsafe locking scenario:

[  440.225244]        CPU0                    CPU1
[  440.225244]        ----                    ----
[  440.225245]   lock(&(&sta->lock)->rlock);
[  440.225245]                                lock(&(&sta->rate_ctrl_lock)->rlock);
[  440.225246]                                lock(&(&sta->lock)->rlock);
[  440.225247]   lock(&(&q->lock)->rlock#2);
[  440.225248]
                *** DEADLOCK ***

[  440.225249] 5 locks held by kworker/u16:28/2362:
[  440.225250]  #0: 0000000048fcd291 ((wq_completion)phy0){+.+.}, at: process_one_work+0x1b5/0x5d0
[  440.225252]  #1: 00000000f1c6828f ((work_completion)(&sta->ampdu_mlme.work)){+.+.}, at: process_one_work+0x1b5/0x5d0
[  440.225254]  #2: 00000000433d2b2c (&sta->ampdu_mlme.mtx){+.+.}, at: ieee80211_ba_session_work+0x5c/0x2f0 [mac80211]
[  440.225265]  #3: 000000002cfedc59 (&(&sta->lock)->rlock){+.-.}, at: ieee80211_stop_tx_ba_cb+0x32/0x1f0 [mac80211]
[  440.225276]  #4: 000000009d7b9a44 (rcu_read_lock){....}, at: ieee80211_agg_start_txq+0x33/0x2b0 [mac80211]
[  440.225286]
               stack backtrace:
[  440.225288] CPU: 2 PID: 2362 Comm: kworker/u16:28 Not tainted 5.1.0-rc2+ #22
[  440.225289] Hardware name: LENOVO 20KGS23S0P/20KGS23S0P, BIOS N23ET55W (1.30 ) 08/31/2018
[  440.225300] Workqueue: phy0 ieee80211_ba_session_work [mac80211]
[  440.225301] Call Trace:
[  440.225304]  dump_stack+0x85/0xc0
[  440.225306]  print_circular_bug.isra.38.cold.58+0x15c/0x195
[  440.225307]  check_prev_add.constprop.48+0x5f0/0xc00
[  440.225309]  ? check_prev_add.constprop.48+0x39d/0xc00
[  440.225311]  ? __lock_acquire+0x41d/0x1100
[  440.225312]  __lock_acquire+0xd98/0x1100
[  440.225313]  ? __lock_acquire+0x41d/0x1100
[  440.225315]  lock_acquire+0xb9/0x1a0
[  440.225317]  ? mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225319]  _raw_spin_lock_bh+0x34/0x40
[  440.225321]  ? mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225323]  mt76_wake_tx_queue+0x4c/0xb0 [mt76]
[  440.225334]  ieee80211_agg_start_txq+0xe8/0x2b0 [mac80211]
[  440.225344]  ieee80211_stop_tx_ba_cb+0xb8/0x1f0 [mac80211]
[  440.225354]  ieee80211_ba_session_work+0x1c1/0x2f0 [mac80211]
[  440.225356]  process_one_work+0x237/0x5d0
[  440.225358]  worker_thread+0x3c/0x390
[  440.225359]  ? wq_calc_node_cpumask+0x70/0x70
[  440.225360]  kthread+0x11d/0x140
[  440.225362]  ? kthread_create_on_node+0x40/0x40
[  440.225363]  ret_from_fork+0x3a/0x50

Cc: stable@vger.kernel.org
Fixes: 88046b2 ("mt76: add support for reporting tx status with skb")
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue May 20, 2019
…mory

[ Upstream commit a6ecfb1 ]

When halting a guest, QEMU flushes the virtual ITS caches, which
amounts to writing to the various tables that the guest has allocated.

When doing this, we fail to take the srcu lock, and the kernel
shouts loudly if running a lockdep kernel:

[   69.680416] =============================
[   69.680819] WARNING: suspicious RCU usage
[   69.681526] 5.1.0-rc1-00008-g600025238f51-dirty #18 Not tainted
[   69.682096] -----------------------------
[   69.682501] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage!
[   69.683225]
[   69.683225] other info that might help us debug this:
[   69.683225]
[   69.683975]
[   69.683975] rcu_scheduler_active = 2, debug_locks = 1
[   69.684598] 6 locks held by qemu-system-aar/4097:
[   69.685059]  #0: 0000000034196013 (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0
[   69.686087]  #1: 00000000f2ed935e (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0
[   69.686919]  #2: 000000005e71ea54 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.687698]  #3: 00000000c17e548d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.688475]  #4: 00000000ba386017 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.689978]  #5: 00000000c2c3c335 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[   69.690729]
[   69.690729] stack backtrace:
[   69.691151] CPU: 2 PID: 4097 Comm: qemu-system-aar Not tainted 5.1.0-rc1-00008-g600025238f51-dirty #18
[   69.691984] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019
[   69.692831] Call trace:
[   69.694072]  lockdep_rcu_suspicious+0xcc/0x110
[   69.694490]  gfn_to_memslot+0x174/0x190
[   69.694853]  kvm_write_guest+0x50/0xb0
[   69.695209]  vgic_its_save_tables_v0+0x248/0x330
[   69.695639]  vgic_its_set_attr+0x298/0x3a0
[   69.696024]  kvm_device_ioctl_attr+0x9c/0xd8
[   69.696424]  kvm_device_ioctl+0x8c/0xf8
[   69.696788]  do_vfs_ioctl+0xc8/0x960
[   69.697128]  ksys_ioctl+0x8c/0xa0
[   69.697445]  __arm64_sys_ioctl+0x28/0x38
[   69.697817]  el0_svc_common+0xd8/0x138
[   69.698173]  el0_svc_handler+0x38/0x78
[   69.698528]  el0_svc+0x8/0xc

The fix is to obviously take the srcu lock, just like we do on the
read side of things since bf30824. One wonders why this wasn't
fixed at the same time, but hey...

Fixes: bf30824 ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
frno7 pushed a commit that referenced this issue May 20, 2019
[ Upstream commit 7494cec ]

Calling kvm_is_visible_gfn() implies that we're parsing the memslots,
and doing this without the srcu lock is frown upon:

[12704.164532] =============================
[12704.164544] WARNING: suspicious RCU usage
[12704.164560] 5.1.0-rc1-00008-g600025238f51-dirty #16 Tainted: G        W
[12704.164573] -----------------------------
[12704.164589] ./include/linux/kvm_host.h:605 suspicious rcu_dereference_check() usage!
[12704.164602] other info that might help us debug this:
[12704.164616] rcu_scheduler_active = 2, debug_locks = 1
[12704.164631] 6 locks held by qemu-system-aar/13968:
[12704.164644]  #0: 000000007ebdae4f (&kvm->lock){+.+.}, at: vgic_its_set_attr+0x244/0x3a0
[12704.164691]  #1: 000000007d751022 (&its->its_lock){+.+.}, at: vgic_its_set_attr+0x250/0x3a0
[12704.164726]  #2: 00000000219d2706 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164761]  #3: 00000000a760aecd (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164794]  #4: 000000000ef8e31d (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164827]  #5: 000000007a872093 (&vcpu->mutex){+.+.}, at: lock_all_vcpus+0x64/0xd0
[12704.164861] stack backtrace:
[12704.164878] CPU: 2 PID: 13968 Comm: qemu-system-aar Tainted: G        W         5.1.0-rc1-00008-g600025238f51-dirty #16
[12704.164887] Hardware name: rockchip evb_rk3399/evb_rk3399, BIOS 2019.04-rc3-00124-g2feec69fb1 03/15/2019
[12704.164896] Call trace:
[12704.164910]  dump_backtrace+0x0/0x138
[12704.164920]  show_stack+0x24/0x30
[12704.164934]  dump_stack+0xbc/0x104
[12704.164946]  lockdep_rcu_suspicious+0xcc/0x110
[12704.164958]  gfn_to_memslot+0x174/0x190
[12704.164969]  kvm_is_visible_gfn+0x28/0x70
[12704.164980]  vgic_its_check_id.isra.0+0xec/0x1e8
[12704.164991]  vgic_its_save_tables_v0+0x1ac/0x330
[12704.165001]  vgic_its_set_attr+0x298/0x3a0
[12704.165012]  kvm_device_ioctl_attr+0x9c/0xd8
[12704.165022]  kvm_device_ioctl+0x8c/0xf8
[12704.165035]  do_vfs_ioctl+0xc8/0x960
[12704.165045]  ksys_ioctl+0x8c/0xa0
[12704.165055]  __arm64_sys_ioctl+0x28/0x38
[12704.165067]  el0_svc_common+0xd8/0x138
[12704.165078]  el0_svc_handler+0x38/0x78
[12704.165089]  el0_svc+0x8/0xc

Make sure the lock is taken when doing this.

Fixes: bf30824 ("KVM: arm/arm64: VGIC/ITS: protect kvm_read_guest() calls with SRCU lock")
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sasha Levin (Microsoft) <sashal@kernel.org>
frno7 pushed a commit that referenced this issue May 20, 2019
[ Upstream commit 1b8f21b ]

In NVMe's error handler, follows the typical steps of tearing down
hardware for recovering controller:

1) stop blk_mq hw queues
2) stop the real hw queues
3) cancel in-flight requests via
	blk_mq_tagset_busy_iter(tags, cancel_request, ...)
cancel_request():
	mark the request as abort
	blk_mq_complete_request(req);
4) destroy real hw queues

However, there may be race between #3 and #4, because blk_mq_complete_request()
may run q->mq_ops->complete(rq) remotelly and asynchronously, and
->complete(rq) may be run after #4.

This patch introduces blk_mq_complete_request_sync() for fixing the
above race.

Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: James Smart <james.smart@broadcom.com>
Cc: linux-nvme@lists.infradead.org
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue May 20, 2019
[ Upstream commit b9abbdf ]

By calling maps__insert() we assume to get 2 references on the map,
which we relese within maps__remove call.

However if there's already same map name, we currently don't bump the
reference and can crash, like:

  Program received signal SIGABRT, Aborted.
  0x00007ffff75e60f5 in raise () from /lib64/libc.so.6

  (gdb) bt
  #0  0x00007ffff75e60f5 in raise () from /lib64/libc.so.6
  #1  0x00007ffff75d0895 in abort () from /lib64/libc.so.6
  #2  0x00007ffff75d0769 in __assert_fail_base.cold () from /lib64/libc.so.6
  #3  0x00007ffff75de596 in __assert_fail () from /lib64/libc.so.6
  #4  0x00000000004fc006 in refcount_sub_and_test (i=1, r=0x1224e88) at tools/include/linux/refcount.h:131
  #5  refcount_dec_and_test (r=0x1224e88) at tools/include/linux/refcount.h:148
  #6  map__put (map=0x1224df0) at util/map.c:299
  #7  0x00000000004fdb95 in __maps__remove (map=0x1224df0, maps=0xb17d80) at util/map.c:953
  #8  maps__remove (maps=0xb17d80, map=0x1224df0) at util/map.c:959
  #9  0x00000000004f7d8a in map_groups__remove (map=<optimized out>, mg=<optimized out>) at util/map_groups.h:65
  #10 machine__process_ksymbol_unregister (sample=<optimized out>, event=0x7ffff7279670, machine=<optimized out>) at util/machine.c:728
  #11 machine__process_ksymbol (machine=<optimized out>, event=0x7ffff7279670, sample=<optimized out>) at util/machine.c:741
  #12 0x00000000004fffbb in perf_session__deliver_event (session=0xb11390, event=0x7ffff7279670, tool=0x7fffffffc7b0, file_offset=13936) at util/session.c:1362
  #13 0x00000000005039bb in do_flush (show_progress=false, oe=0xb17e80) at util/ordered-events.c:243
  #14 __ordered_events__flush (oe=0xb17e80, how=OE_FLUSH__ROUND, timestamp=<optimized out>) at util/ordered-events.c:322
  #15 0x00000000005005e4 in perf_session__process_user_event (session=session@entry=0xb11390, event=event@entry=0x7ffff72a4af8,
  ...

Add the map to the list and getting the reference event if we find the
map with same name.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Fixes: 1e62856 ("perf symbols: Fix slowness due to -ffunction-section")
Link: http://lkml.kernel.org/r/20190416160127.30203-10-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Jun 21, 2019
commit dea37a9 upstream.

Syzkaller report this:

BUG: KASAN: use-after-free in sysfs_remove_file_ns+0x5f/0x70 fs/sysfs/file.c:468
Read of size 8 at addr ffff8881f59a6b70 by task syz-executor.0/8363

CPU: 0 PID: 8363 Comm: syz-executor.0 Not tainted 5.0.0-rc8+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xfa/0x1ce lib/dump_stack.c:113
 print_address_description+0x65/0x270 mm/kasan/report.c:187
 kasan_report+0x149/0x18d mm/kasan/report.c:317
 sysfs_remove_file_ns+0x5f/0x70 fs/sysfs/file.c:468
 sysfs_remove_file include/linux/sysfs.h:519 [inline]
 driver_remove_file+0x40/0x50 drivers/base/driver.c:122
 usb_remove_newid_files drivers/usb/core/driver.c:212 [inline]
 usb_deregister+0x12a/0x3b0 drivers/usb/core/driver.c:1005
 cpia2_exit+0xa/0x16 [cpia2]
 __do_sys_delete_module kernel/module.c:1018 [inline]
 __se_sys_delete_module kernel/module.c:961 [inline]
 __x64_sys_delete_module+0x3dc/0x5e0 kernel/module.c:961
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f86f3754c58 EFLAGS: 00000246 ORIG_RAX: 00000000000000b0
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000300
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f86f37556bc
R13: 00000000004bcca9 R14: 00000000006f6b48 R15: 00000000ffffffff

Allocated by task 8363:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:495
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 bus_add_driver+0xc0/0x610 drivers/base/bus.c:651
 driver_register+0x1bb/0x3f0 drivers/base/driver.c:170
 usb_register_driver+0x267/0x520 drivers/usb/core/driver.c:965
 0xffffffffc1b4817c
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 8363:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:457
 slab_free_hook mm/slub.c:1430 [inline]
 slab_free_freelist_hook mm/slub.c:1457 [inline]
 slab_free mm/slub.c:3005 [inline]
 kfree+0xe1/0x270 mm/slub.c:3957
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:67 [inline]
 kobject_put+0x146/0x240 lib/kobject.c:708
 bus_remove_driver+0x10e/0x220 drivers/base/bus.c:732
 driver_unregister+0x6c/0xa0 drivers/base/driver.c:197
 usb_register_driver+0x341/0x520 drivers/usb/core/driver.c:980
 0xffffffffc1b4817c
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881f59a6b40
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 48 bytes inside of
 256-byte region [ffff8881f59a6b40, ffff8881f59a6c40)
The buggy address belongs to the page:
page:ffffea0007d66980 count:1 mapcount:0 mapping:ffff8881f6c02e00 index:0x0
flags: 0x2fffc0000000200(slab)
raw: 02fffc0000000200 dead000000000100 dead000000000200 ffff8881f6c02e00
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881f59a6a00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881f59a6a80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc
>ffff8881f59a6b00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                             ^
 ffff8881f59a6b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881f59a6c00: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc

cpia2_init does not check return value of cpia2_init, if it failed
in usb_register_driver, there is already cleanup using driver_unregister.
No need call cpia2_usb_cleanup on module exit.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Jun 21, 2019
commit 56cd26b upstream.

Syzkaller report this:

BUG: KASAN: use-after-free in sysfs_remove_file_ns+0x5f/0x70 fs/sysfs/file.c:468
Read of size 8 at addr ffff8881dc7ae030 by task syz-executor.0/6249

CPU: 1 PID: 6249 Comm: syz-executor.0 Not tainted 5.0.0-rc8+ #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xfa/0x1ce lib/dump_stack.c:113
 print_address_description+0x65/0x270 mm/kasan/report.c:187
 kasan_report+0x149/0x18d mm/kasan/report.c:317
 ? 0xffffffffc1728000
 sysfs_remove_file_ns+0x5f/0x70 fs/sysfs/file.c:468
 sysfs_remove_file include/linux/sysfs.h:519 [inline]
 driver_remove_file+0x40/0x50 drivers/base/driver.c:122
 remove_bind_files drivers/base/bus.c:585 [inline]
 bus_remove_driver+0x186/0x220 drivers/base/bus.c:725
 driver_unregister+0x6c/0xa0 drivers/base/driver.c:197
 serial_ir_init_module+0x169/0x1000 [serial_ir]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x462e99
Code: f7 d8 64 89 02 b8 ff ff ff ff c3 66 0f 1f 44 00 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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9450132c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
RAX: ffffffffffffffda RBX: 000000000073bf00 RCX: 0000000000462e99
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00007f9450132c70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f94501336bc
R13: 00000000004bcefa R14: 00000000006f6fb0 R15: 0000000000000004

Allocated by task 6249:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_kmalloc.constprop.3+0xa0/0xd0 mm/kasan/common.c:495
 kmalloc include/linux/slab.h:545 [inline]
 kzalloc include/linux/slab.h:740 [inline]
 bus_add_driver+0xc0/0x610 drivers/base/bus.c:651
 driver_register+0x1bb/0x3f0 drivers/base/driver.c:170
 serial_ir_init_module+0xe8/0x1000 [serial_ir]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 6249:
 set_track mm/kasan/common.c:85 [inline]
 __kasan_slab_free+0x130/0x180 mm/kasan/common.c:457
 slab_free_hook mm/slub.c:1430 [inline]
 slab_free_freelist_hook mm/slub.c:1457 [inline]
 slab_free mm/slub.c:3005 [inline]
 kfree+0xe1/0x270 mm/slub.c:3957
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:67 [inline]
 kobject_put+0x146/0x240 lib/kobject.c:708
 bus_remove_driver+0x10e/0x220 drivers/base/bus.c:732
 driver_unregister+0x6c/0xa0 drivers/base/driver.c:197
 serial_ir_init_module+0x14c/0x1000 [serial_ir]
 do_one_initcall+0xfa/0x5ca init/main.c:887
 do_init_module+0x204/0x5f6 kernel/module.c:3460
 load_module+0x66b2/0x8570 kernel/module.c:3808
 __do_sys_finit_module+0x238/0x2a0 kernel/module.c:3902
 do_syscall_64+0x147/0x600 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8881dc7ae000
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 48 bytes inside of
 256-byte region [ffff8881dc7ae000, ffff8881dc7ae100)
The buggy address belongs to the page:
page:ffffea000771eb80 count:1 mapcount:0 mapping:ffff8881f6c02e00 index:0x0
flags: 0x2fffc0000000200(slab)
raw: 02fffc0000000200 ffffea0007d14800 0000000400000002 ffff8881f6c02e00
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881dc7adf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881dc7adf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881dc7ae000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8881dc7ae080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881dc7ae100: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00

There are already cleanup handlings in serial_ir_init error path,
no need to call serial_ir_exit do it again in serial_ir_init_module,
otherwise will trigger a use-after-free issue.

Fixes: fa5dc29 ("[media] lirc_serial: move out of staging and rename to serial_ir")

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Jun 21, 2019
[ Upstream commit f80c5da ]

This commit makes the kernel not send the next queued HCI command until
a command complete arrives for the last HCI command sent to the
controller. This change avoids a problem with some buggy controllers
(seen on two SKUs of QCA9377) that send an extra command complete event
for the previous command after the kernel had already sent a new HCI
command to the controller.

The problem was reproduced when starting an active scanning procedure,
where an extra command complete event arrives for the LE_SET_RANDOM_ADDR
command. When this happends the kernel ends up not processing the
command complete for the following commmand, LE_SET_SCAN_PARAM, and
ultimately behaving as if a passive scanning procedure was being
performed, when in fact controller is performing an active scanning
procedure. This makes it impossible to discover BLE devices as no device
found events are sent to userspace.

This problem is reproducible on 100% of the attempts on the affected
controllers. The extra command complete event can be seen at timestamp
27.420131 on the btmon logs bellow.

Bluetooth monitor ver 5.50
= Note: Linux version 5.0.0+ (x86_64)                                  0.352340
= Note: Bluetooth subsystem version 2.22                               0.352343
= New Index: 80:C5:F2:8F:87:84 (Primary,USB,hci0)               [hci0] 0.352344
= Open Index: 80:C5:F2:8F:87:84                                 [hci0] 0.352345
= Index Info: 80:C5:F2:8F:87:84 (Qualcomm)                      [hci0] 0.352346
@ MGMT Open: bluetoothd (privileged) version 1.14             {0x0001} 0.352347
@ MGMT Open: btmon (privileged) version 1.14                  {0x0002} 0.352366
@ MGMT Open: btmgmt (privileged) version 1.14                {0x0003} 27.302164
@ MGMT Command: Start Discovery (0x0023) plen 1       {0x0003} [hci0] 27.302310
        Address type: 0x06
          LE Public
          LE Random
< HCI Command: LE Set Random Address (0x08|0x0005) plen 6   #1 [hci0] 27.302496
        Address: 15:60:F2:91:B2:24 (Non-Resolvable)
> HCI Event: Command Complete (0x0e) plen 4                 #2 [hci0] 27.419117
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7  #3 [hci0] 27.419244
        Type: Active (0x01)
        Interval: 11.250 msec (0x0012)
        Window: 11.250 msec (0x0012)
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #4 [hci0] 27.420131
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2      #5 [hci0] 27.420259
        Scanning: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4                 #6 [hci0] 27.420969
      LE Set Scan Parameters (0x08|0x000b) ncmd 1
        Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #7 [hci0] 27.421983
      LE Set Scan Enable (0x08|0x000c) ncmd 1
        Status: Success (0x00)
@ MGMT Event: Command Complete (0x0001) plen 4        {0x0003} [hci0] 27.422059
      Start Discovery (0x0023) plen 1
        Status: Success (0x00)
        Address type: 0x06
          LE Public
          LE Random
@ MGMT Event: Discovering (0x0013) plen 2             {0x0003} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0002} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0001} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)

Signed-off-by: João Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Jun 21, 2019
[ Upstream commit 41a91c6 ]

dwc3_gadget_suspend() is called under dwc->lock spinlock. In such context
calling synchronize_irq() is not allowed. Move the problematic call out
of the protected block to fix the following kernel BUG during system
suspend:

BUG: sleeping function called from invalid context at kernel/irq/manage.c:112
in_atomic(): 1, irqs_disabled(): 128, pid: 1601, name: rtcwake
6 locks held by rtcwake/1601:
 #0: f70ac2a2 (sb_writers#7){.+.+}, at: vfs_write+0x130/0x16c
 #1: b5fe1270 (&of->mutex){+.+.}, at: kernfs_fop_write+0xc0/0x1e4
 #2: 7e597705 (kn->count#60){.+.+}, at: kernfs_fop_write+0xc8/0x1e4
 #3: 8b3527d0 (system_transition_mutex){+.+.}, at: pm_suspend+0xc4/0xc04
 #4: fc7f1c42 (&dev->mutex){....}, at: __device_suspend+0xd8/0x74c
 #5: 4b36507e (&(&dwc->lock)->rlock){....}, at: dwc3_gadget_suspend+0x24/0x3c
irq event stamp: 11252
hardirqs last  enabled at (11251): [<c09c54a4>] _raw_spin_unlock_irqrestore+0x6c/0x74
hardirqs last disabled at (11252): [<c09c4d44>] _raw_spin_lock_irqsave+0x1c/0x5c
softirqs last  enabled at (9744): [<c0102564>] __do_softirq+0x3a4/0x66c
softirqs last disabled at (9737): [<c0128528>] irq_exit+0x140/0x168
Preemption disabled at:
[<00000000>]   (null)
CPU: 7 PID: 1601 Comm: rtcwake Not tainted
5.0.0-rc3-next-20190122-00039-ga3f4ee4f8a52 #5252
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
[<c01110f0>] (unwind_backtrace) from [<c010d120>] (show_stack+0x10/0x14)
[<c010d120>] (show_stack) from [<c09a4d04>] (dump_stack+0x90/0xc8)
[<c09a4d04>] (dump_stack) from [<c014c700>] (___might_sleep+0x22c/0x2c8)
[<c014c700>] (___might_sleep) from [<c0189d68>] (synchronize_irq+0x28/0x84)
[<c0189d68>] (synchronize_irq) from [<c05cbbf8>] (dwc3_gadget_suspend+0x34/0x3c)
[<c05cbbf8>] (dwc3_gadget_suspend) from [<c05bd020>] (dwc3_suspend_common+0x154/0x410)
[<c05bd020>] (dwc3_suspend_common) from [<c05bd34c>] (dwc3_suspend+0x14/0x2c)
[<c05bd34c>] (dwc3_suspend) from [<c051c730>] (platform_pm_suspend+0x2c/0x54)
[<c051c730>] (platform_pm_suspend) from [<c05285d4>] (dpm_run_callback+0xa4/0x3dc)
[<c05285d4>] (dpm_run_callback) from [<c0528a40>] (__device_suspend+0x134/0x74c)
[<c0528a40>] (__device_suspend) from [<c052c508>] (dpm_suspend+0x174/0x588)
[<c052c508>] (dpm_suspend) from [<c0182134>] (suspend_devices_and_enter+0xc0/0xe74)
[<c0182134>] (suspend_devices_and_enter) from [<c0183658>] (pm_suspend+0x770/0xc04)
[<c0183658>] (pm_suspend) from [<c0180ddc>] (state_store+0x6c/0xcc)
[<c0180ddc>] (state_store) from [<c09a9a70>] (kobj_attr_store+0x14/0x20)
[<c09a9a70>] (kobj_attr_store) from [<c02d6800>] (sysfs_kf_write+0x4c/0x50)
[<c02d6800>] (sysfs_kf_write) from [<c02d594c>] (kernfs_fop_write+0xfc/0x1e4)
[<c02d594c>] (kernfs_fop_write) from [<c02593d8>] (__vfs_write+0x2c/0x160)
[<c02593d8>] (__vfs_write) from [<c0259694>] (vfs_write+0xa4/0x16c)
[<c0259694>] (vfs_write) from [<c0259870>] (ksys_write+0x40/0x8c)
[<c0259870>] (ksys_write) from [<c0101000>] (ret_fast_syscall+0x0/0x28)
Exception stack(0xed55ffa8 to 0xed55fff0)
...

Fixes: 01c1088 ("usb: dwc3: gadget: synchronize_irq dwc irq in suspend")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Jun 21, 2019
…cm_qla2xxx_close_session()

[ Upstream commit d4023db ]

This patch avoids that lockdep reports the following warning:

=====================================================
WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
5.1.0-rc1-dbg+ #11 Tainted: G        W
-----------------------------------------------------
rmdir/1478 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
00000000e7ac4607 (&(&k->k_lock)->rlock){+.+.}, at: klist_next+0x43/0x1d0

and this task is already holding:
00000000cf0baf5e (&(&ha->tgt.sess_lock)->rlock){-...}, at: tcm_qla2xxx_close_session+0x57/0xb0 [tcm_qla2xxx]
which would create a new lock dependency:
 (&(&ha->tgt.sess_lock)->rlock){-...} -> (&(&k->k_lock)->rlock){+.+.}

but this new dependency connects a HARDIRQ-irq-safe lock:
 (&(&ha->tgt.sess_lock)->rlock){-...}

... which became HARDIRQ-irq-safe at:
  lock_acquire+0xe3/0x200
  _raw_spin_lock_irqsave+0x3d/0x60
  qla2x00_fcport_event_handler+0x1f3d/0x22b0 [qla2xxx]
  qla2x00_async_login_sp_done+0x1dc/0x1f0 [qla2xxx]
  qla24xx_process_response_queue+0xa37/0x10e0 [qla2xxx]
  qla24xx_msix_rsp_q+0x79/0xf0 [qla2xxx]
  __handle_irq_event_percpu+0x79/0x3c0
  handle_irq_event_percpu+0x70/0xf0
  handle_irq_event+0x5a/0x8b
  handle_edge_irq+0x12c/0x310
  handle_irq+0x192/0x20a
  do_IRQ+0x73/0x160
  ret_from_intr+0x0/0x1d
  default_idle+0x23/0x1f0
  arch_cpu_idle+0x15/0x20
  default_idle_call+0x35/0x40
  do_idle+0x2bb/0x2e0
  cpu_startup_entry+0x1d/0x20
  start_secondary+0x24d/0x2d0
  secondary_startup_64+0xa4/0xb0

to a HARDIRQ-irq-unsafe lock:
 (&(&k->k_lock)->rlock){+.+.}

... which became HARDIRQ-irq-unsafe at:
...
  lock_acquire+0xe3/0x200
  _raw_spin_lock+0x32/0x50
  klist_add_tail+0x33/0xb0
  device_add+0x7f4/0xb60
  device_create_groups_vargs+0x11c/0x150
  device_create_with_groups+0x89/0xb0
  vtconsole_class_init+0xb2/0x124
  do_one_initcall+0xc5/0x3ce
  kernel_init_freeable+0x295/0x32e
  kernel_init+0x11/0x11b
  ret_from_fork+0x3a/0x50

other info that might help us debug this:

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&k->k_lock)->rlock);
                               local_irq_disable();
                               lock(&(&ha->tgt.sess_lock)->rlock);
                               lock(&(&k->k_lock)->rlock);
  <Interrupt>
    lock(&(&ha->tgt.sess_lock)->rlock);

 *** DEADLOCK ***

4 locks held by rmdir/1478:
 #0: 000000002c7f1ba4 (sb_writers#10){.+.+}, at: mnt_want_write+0x32/0x70
 #1: 00000000c85eb147 (&default_group_class[depth - 1]#2/1){+.+.}, at: do_rmdir+0x217/0x2d0
 #2: 000000002b164d6f (&sb->s_type->i_mutex_key#13){++++}, at: vfs_rmdir+0x7e/0x1d0
 #3: 00000000cf0baf5e (&(&ha->tgt.sess_lock)->rlock){-...}, at: tcm_qla2xxx_close_session+0x57/0xb0 [tcm_qla2xxx]

the dependencies between HARDIRQ-irq-safe lock and the holding lock:
-> (&(&ha->tgt.sess_lock)->rlock){-...} ops: 127 {
   IN-HARDIRQ-W at:
                    lock_acquire+0xe3/0x200
                    _raw_spin_lock_irqsave+0x3d/0x60
                    qla2x00_fcport_event_handler+0x1f3d/0x22b0 [qla2xxx]
                    qla2x00_async_login_sp_done+0x1dc/0x1f0 [qla2xxx]
                    qla24xx_process_response_queue+0xa37/0x10e0 [qla2xxx]
                    qla24xx_msix_rsp_q+0x79/0xf0 [qla2xxx]
                    __handle_irq_event_percpu+0x79/0x3c0
                    handle_irq_event_percpu+0x70/0xf0
                    handle_irq_event+0x5a/0x8b
                    handle_edge_irq+0x12c/0x310
                    handle_irq+0x192/0x20a
                    do_IRQ+0x73/0x160
                    ret_from_intr+0x0/0x1d
                    default_idle+0x23/0x1f0
                    arch_cpu_idle+0x15/0x20
                    default_idle_call+0x35/0x40
                    do_idle+0x2bb/0x2e0
                    cpu_startup_entry+0x1d/0x20
                    start_secondary+0x24d/0x2d0
                    secondary_startup_64+0xa4/0xb0
   INITIAL USE at:
                   lock_acquire+0xe3/0x200
                   _raw_spin_lock_irqsave+0x3d/0x60
                   qla2x00_loop_resync+0xb3d/0x2690 [qla2xxx]
                   qla2x00_do_dpc+0xcee/0xf30 [qla2xxx]
                   kthread+0x1d2/0x1f0
                   ret_from_fork+0x3a/0x50
 }
 ... key      at: [<ffffffffa125f700>] __key.62804+0x0/0xfffffffffff7e900 [qla2xxx]
 ... acquired at:
   __lock_acquire+0x11ed/0x1b60
   lock_acquire+0xe3/0x200
   _raw_spin_lock_irqsave+0x3d/0x60
   klist_next+0x43/0x1d0
   device_for_each_child+0x96/0x110
   scsi_target_block+0x3c/0x40 [scsi_mod]
   fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc]
   qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx]
   qlt_unreg_sess+0x104/0x2c0 [qla2xxx]
   tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx]
   target_shutdown_sessions+0x17b/0x190 [target_core_mod]
   core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod]
   target_fabric_nacl_base_release+0x25/0x30 [target_core_mod]
   config_item_release+0x9f/0x120 [configfs]
   config_item_put+0x29/0x2b [configfs]
   configfs_rmdir+0x3d2/0x520 [configfs]
   vfs_rmdir+0xb3/0x1d0
   do_rmdir+0x25c/0x2d0
   __x64_sys_rmdir+0x24/0x30
   do_syscall_64+0x77/0x220
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

the dependencies between the lock to be acquired
 and HARDIRQ-irq-unsafe lock:
-> (&(&k->k_lock)->rlock){+.+.} ops: 14568 {
   HARDIRQ-ON-W at:
                    lock_acquire+0xe3/0x200
                    _raw_spin_lock+0x32/0x50
                    klist_add_tail+0x33/0xb0
                    device_add+0x7f4/0xb60
                    device_create_groups_vargs+0x11c/0x150
                    device_create_with_groups+0x89/0xb0
                    vtconsole_class_init+0xb2/0x124
                    do_one_initcall+0xc5/0x3ce
                    kernel_init_freeable+0x295/0x32e
                    kernel_init+0x11/0x11b
                    ret_from_fork+0x3a/0x50
   SOFTIRQ-ON-W at:
                    lock_acquire+0xe3/0x200
                    _raw_spin_lock+0x32/0x50
                    klist_add_tail+0x33/0xb0
                    device_add+0x7f4/0xb60
                    device_create_groups_vargs+0x11c/0x150
                    device_create_with_groups+0x89/0xb0
                    vtconsole_class_init+0xb2/0x124
                    do_one_initcall+0xc5/0x3ce
                    kernel_init_freeable+0x295/0x32e
                    kernel_init+0x11/0x11b
                    ret_from_fork+0x3a/0x50
   INITIAL USE at:
                   lock_acquire+0xe3/0x200
                   _raw_spin_lock+0x32/0x50
                   klist_add_tail+0x33/0xb0
                   device_add+0x7f4/0xb60
                   device_create_groups_vargs+0x11c/0x150
                   device_create_with_groups+0x89/0xb0
                   vtconsole_class_init+0xb2/0x124
                   do_one_initcall+0xc5/0x3ce
                   kernel_init_freeable+0x295/0x32e
                   kernel_init+0x11/0x11b
                   ret_from_fork+0x3a/0x50
 }
 ... key      at: [<ffffffff83f3d900>] __key.15805+0x0/0x40
 ... acquired at:
   __lock_acquire+0x11ed/0x1b60
   lock_acquire+0xe3/0x200
   _raw_spin_lock_irqsave+0x3d/0x60
   klist_next+0x43/0x1d0
   device_for_each_child+0x96/0x110
   scsi_target_block+0x3c/0x40 [scsi_mod]
   fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc]
   qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx]
   qlt_unreg_sess+0x104/0x2c0 [qla2xxx]
   tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx]
   target_shutdown_sessions+0x17b/0x190 [target_core_mod]
   core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod]
   target_fabric_nacl_base_release+0x25/0x30 [target_core_mod]
   config_item_release+0x9f/0x120 [configfs]
   config_item_put+0x29/0x2b [configfs]
   configfs_rmdir+0x3d2/0x520 [configfs]
   vfs_rmdir+0xb3/0x1d0
   do_rmdir+0x25c/0x2d0
   __x64_sys_rmdir+0x24/0x30
   do_syscall_64+0x77/0x220
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

stack backtrace:
CPU: 7 PID: 1478 Comm: rmdir Tainted: G        W         5.1.0-rc1-dbg+ #11
Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
Call Trace:
 dump_stack+0x86/0xca
 check_usage.cold.59+0x473/0x563
 check_prev_add.constprop.43+0x1f1/0x1170
 __lock_acquire+0x11ed/0x1b60
 lock_acquire+0xe3/0x200
 _raw_spin_lock_irqsave+0x3d/0x60
 klist_next+0x43/0x1d0
 device_for_each_child+0x96/0x110
 scsi_target_block+0x3c/0x40 [scsi_mod]
 fc_remote_port_delete+0xe7/0x1c0 [scsi_transport_fc]
 qla2x00_mark_device_lost+0x4d3/0x500 [qla2xxx]
 qlt_unreg_sess+0x104/0x2c0 [qla2xxx]
 tcm_qla2xxx_close_session+0xa2/0xb0 [tcm_qla2xxx]
 target_shutdown_sessions+0x17b/0x190 [target_core_mod]
 core_tpg_del_initiator_node_acl+0xf3/0x1f0 [target_core_mod]
 target_fabric_nacl_base_release+0x25/0x30 [target_core_mod]
 config_item_release+0x9f/0x120 [configfs]
 config_item_put+0x29/0x2b [configfs]
 configfs_rmdir+0x3d2/0x520 [configfs]
 vfs_rmdir+0xb3/0x1d0
 do_rmdir+0x25c/0x2d0
 __x64_sys_rmdir+0x24/0x30
 do_syscall_64+0x77/0x220
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Cc: Himanshu Madhani <hmadhani@marvell.com>
Cc: Giridhar Malavali <gmalavali@marvell.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Jun 21, 2019
[ Upstream commit ff612ba ]

We've been seeing the following sporadically throughout our fleet

panic: kernel BUG at fs/btrfs/relocation.c:4584!
netversion: 5.0-0
Backtrace:
 #0 [ffffc90003adb880] machine_kexec at ffffffff81041da8
 #1 [ffffc90003adb8c8] __crash_kexec at ffffffff8110396c
 #2 [ffffc90003adb988] crash_kexec at ffffffff811048ad
 #3 [ffffc90003adb9a0] oops_end at ffffffff8101c19a
 #4 [ffffc90003adb9c0] do_trap at ffffffff81019114
 #5 [ffffc90003adba00] do_error_trap at ffffffff810195d0
 #6 [ffffc90003adbab0] invalid_op at ffffffff81a00a9b
    [exception RIP: btrfs_reloc_cow_block+692]
    RIP: ffffffff8143b614  RSP: ffffc90003adbb68  RFLAGS: 00010246
    RAX: fffffffffffffff7  RBX: ffff8806b9c32000  RCX: ffff8806aad00690
    RDX: ffff880850b295e0  RSI: ffff8806b9c32000  RDI: ffff88084f205bd0
    RBP: ffff880849415000   R8: ffffc90003adbbe0   R9: ffff88085ac90000
    R10: ffff8805f7369140  R11: 0000000000000000  R12: ffff880850b295e0
    R13: ffff88084f205bd0  R14: 0000000000000000  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #7 [ffffc90003adbbb0] __btrfs_cow_block at ffffffff813bf1cd
 #8 [ffffc90003adbc28] btrfs_cow_block at ffffffff813bf4b3
 #9 [ffffc90003adbc78] btrfs_search_slot at ffffffff813c2e6c

The way relocation moves data extents is by creating a reloc inode and
preallocating extents in this inode and then copying the data into these
preallocated extents.  Once we've done this for all of our extents,
we'll write out these dirty pages, which marks the extent written, and
goes into btrfs_reloc_cow_block().  From here we get our current
reloc_control, which _should_ match the reloc_control for the current
block group we're relocating.

However if we get an ENOSPC in this path at some point we'll bail out,
never initiating writeback on this inode.  Not a huge deal, unless we
happen to be doing relocation on a different block group, and this block
group is now rc->stage == UPDATE_DATA_PTRS.  This trips the BUG_ON() in
btrfs_reloc_cow_block(), because we expect to be done modifying the data
inode.  We are in fact done modifying the metadata for the data inode
we're currently using, but not the one from the failed block group, and
thus we BUG_ON().

(This happens when writeback finishes for extents from the previous
group, when we are at btrfs_finish_ordered_io() which updates the data
reloc tree (inode item, drops/adds extent items, etc).)

Fix this by writing out the reloc data inode always, and then breaking
out of the loop after that point to keep from tripping this BUG_ON()
later.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
[ add note from Filipe ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
frno7 pushed a commit that referenced this issue Jul 17, 2019
commit c952b35 upstream.

bpf/btf write_* functions need ff->ph->env.

With this missing, pipe-mode (perf record -o -)  would crash like:

Program terminated with signal SIGSEGV, Segmentation fault.

This patch assign proper ph value to ff.

Committer testing:

  (gdb) run record -o -
  Starting program: /root/bin/perf record -o -
  PERFILE2
  <SNIP start of perf.data headers>
  Thread 1 "perf" received signal SIGSEGV, Segmentation fault.
  __do_write_buf (size=4, buf=0x160, ff=0x7fffffff8f80) at util/header.c:126
  126		memcpy(ff->buf + ff->offset, buf, size);
  (gdb) bt
  #0  __do_write_buf (size=4, buf=0x160, ff=0x7fffffff8f80) at util/header.c:126
  #1  do_write (ff=ff@entry=0x7fffffff8f80, buf=buf@entry=0x160, size=4) at util/header.c:137
  #2  0x00000000004eddba in write_bpf_prog_info (ff=0x7fffffff8f80, evlist=<optimized out>) at util/header.c:912
  #3  0x00000000004f69d7 in perf_event__synthesize_features (tool=tool@entry=0x97cc00 <record>, session=session@entry=0x7fffe9c6d010,
      evlist=0x7fffe9cae010, process=process@entry=0x4435d0 <process_synthesized_event>) at util/header.c:3695
  #4  0x0000000000443c79 in record__synthesize (tail=tail@entry=false, rec=0x97cc00 <record>) at builtin-record.c:1214
  #5  0x0000000000444ec9 in __cmd_record (rec=0x97cc00 <record>, argv=<optimized out>, argc=0) at builtin-record.c:1435
  #6  cmd_record (argc=0, argv=<optimized out>) at builtin-record.c:2450
  #7  0x00000000004ae3e9 in run_builtin (p=p@entry=0x98e058 <commands+216>, argc=argc@entry=3, argv=0x7fffffffd670) at perf.c:304
  #8  0x000000000042eded in handle_internal_command (argv=<optimized out>, argc=<optimized out>) at perf.c:356
  #9  run_argv (argcp=<optimized out>, argv=<optimized out>) at perf.c:400
  #10 main (argc=3, argv=<optimized out>) at perf.c:522
  (gdb)

After the patch the SEGSEGV is gone.

Reported-by: David Carrillo Cisneros <davidca@fb.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: kernel-team@fb.com
Cc: stable@vger.kernel.org # v5.1+
Fixes: 606f972 ("perf bpf: Save bpf_prog_info information as headers to perf.data")
Link: http://lkml.kernel.org/r/20190620010453.4118689-1-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
frno7 pushed a commit that referenced this issue Sep 1, 2019
Revert the commit bd293d0. The proper
fix has been made available with commit d0a255e ("loop: set
PF_MEMALLOC_NOIO for the worker thread").

Note that the fix offered by commit bd293d0 doesn't really prevent
the deadlock from occuring - if we look at the stacktrace reported by
Junxiao Bi, we see that it hangs in bit_wait_io and not on the mutex -
i.e. it has already successfully taken the mutex. Changing the mutex
from mutex_lock to mutex_trylock won't help with deadlocks that happen
afterwards.

PID: 474    TASK: ffff8813e11f4600  CPU: 10  COMMAND: "kswapd0"
   #0 [ffff8813dedfb938] __schedule at ffffffff8173f405
   #1 [ffff8813dedfb990] schedule at ffffffff8173fa27
   #2 [ffff8813dedfb9b0] schedule_timeout at ffffffff81742fec
   #3 [ffff8813dedfba60] io_schedule_timeout at ffffffff8173f186
   #4 [ffff8813dedfbaa0] bit_wait_io at ffffffff8174034f
   #5 [ffff8813dedfbac0] __wait_on_bit at ffffffff8173fec8
   #6 [ffff8813dedfbb10] out_of_line_wait_on_bit at ffffffff8173ff81
   #7 [ffff8813dedfbb90] __make_buffer_clean at ffffffffa038736f [dm_bufio]
   #8 [ffff8813dedfbbb0] __try_evict_buffer at ffffffffa0387bb8 [dm_bufio]
   #9 [ffff8813dedfbbd0] dm_bufio_shrink_scan at ffffffffa0387cc3 [dm_bufio]
  #10 [ffff8813dedfbc40] shrink_slab at ffffffff811a87ce
  #11 [ffff8813dedfbd30] shrink_zone at ffffffff811ad778
  #12 [ffff8813dedfbdc0] kswapd at ffffffff811ae92f
  #13 [ffff8813dedfbec0] kthread at ffffffff810a8428
  #14 [ffff8813dedfbf50] ret_from_fork at ffffffff81745242

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org
Fixes: bd293d0 ("dm bufio: fix deadlock with loop device")
Depends-on: d0a255e ("loop: set PF_MEMALLOC_NOIO for the worker thread")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
frno7 pushed a commit that referenced this issue Sep 1, 2019
reply_cache_stats uses wrong parameter as seq file private structure and
thus causes the following kernel crash when users read
/proc/fs/nfsd/reply_cache_stats

BUG: kernel NULL pointer dereference, address: 00000000000001f9
PGD 0 P4D 0
Oops: 0000 [#3] SMP PTI
CPU: 6 PID: 1502 Comm: cat Tainted: G      D           5.3.0-rc3+ #1
Hardware name: Intel Corporation Broadwell Client platform/Basking Ridge, BIOS BDW-E2R1.86C.0118.R01.1503110618 03/11/2015
RIP: 0010:nfsd_reply_cache_stats_show+0x3b/0x2d0
Code: 41 54 49 89 f4 48 89 fe 48 c7 c7 b3 10 33 88 53 bb e8 03 00 00 e8 88 82 d1 ff bf 58 89 41 00 e8 eb c5 85 00 48 83 eb 01 75 f0 <41> 8b 94 24 f8 01 00 00 48 c7 c6 be 10 33 88 4c 89 ef bb e8 03 00
RSP: 0018:ffffaa520106fe08 EFLAGS: 00010246
RAX: 000000cfe1a77123 RBX: 0000000000000000 RCX: 0000000000291b46
RDX: 000000cf00000000 RSI: 0000000000000006 RDI: 0000000000291b28
RBP: ffffaa520106fe20 R08: 0000000000000006 R09: 000000cfe17e55dd
R10: ffffa424e47c0000 R11: 000000000000030b R12: 0000000000000001
R13: ffffa424e5697000 R14: 0000000000000001 R15: ffffa424e5697000
FS:  00007f805735f580(0000) GS:ffffa424f8f80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000001f9 CR3: 00000000655ce005 CR4: 00000000003606e0
Call Trace:
 seq_read+0x194/0x3e0
 __vfs_read+0x1b/0x40
 vfs_read+0x95/0x140
 ksys_read+0x61/0xe0
 __x64_sys_read+0x1a/0x20
 do_syscall_64+0x4d/0x120
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f805728b861
Code: fe ff ff 50 48 8d 3d 86 b4 09 00 e8 79 e0 01 00 66 0f 1f 84 00 00 00 00 00 48 8d 05 d9 19 0d 00 8b 00 85 c0 75 13 31 c0 0f 05 <48> 3d 00 f0 ff ff 77 57 c3 66 0f 1f 44 00 00 48 83 ec 28 48 89 54
RSP: 002b:00007ffea1ce3c38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000020000 RCX: 00007f805728b861
RDX: 0000000000020000 RSI: 00007f8057183000 RDI: 0000000000000003
RBP: 00007f8057183000 R08: 00007f8057182010 R09: 0000000000000000
R10: 0000000000000022 R11: 0000000000000246 R12: 0000559a60e8ff10
R13: 0000000000000003 R14: 0000000000020000 R15: 0000000000020000
Modules linked in:
CR2: 00000000000001f9
---[ end trace 01613595153f0cba ]---
RIP: 0010:nfsd_reply_cache_stats_show+0x3b/0x2d0
Code: 41 54 49 89 f4 48 89 fe 48 c7 c7 b3 10 33 88 53 bb e8 03 00 00 e8 88 82 d1 ff bf 58 89 41 00 e8 eb c5 85 00 48 83 eb 01 75 f0 <41> 8b 94 24 f8 01 00 00 48 c7 c6 be 10 33 88 4c 89 ef bb e8 03 00
RSP: 0018:ffffaa52004b3e08 EFLAGS: 00010246
RAX: 0000002bab45a7c6 RBX: 0000000000000000 RCX: 0000000000291b4c
RDX: 0000002b00000000 RSI: 0000000000000004 RDI: 0000000000291b28
RBP: ffffaa52004b3e20 R08: 0000000000000004 R09: 0000002bab1c8c7a
R10: ffffa424e5500000 R11: 00000000000002a9 R12: 0000000000000001
R13: ffffa424e4475000 R14: 0000000000000001 R15: ffffa424e4475000
FS:  00007f805735f580(0000) GS:ffffa424f8f80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000001f9 CR3: 00000000655ce005 CR4: 00000000003606e0
Killed

Fixes: 3ba7583 ("nfsd4: drc containerization")
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
frno7 pushed a commit that referenced this issue Sep 1, 2019
…s_blob()

Calling ceph_buffer_put() in __ceph_build_xattrs_blob() may result in
freeing the i_xattrs.blob buffer while holding the i_ceph_lock.  This can
be fixed by having this function returning the old blob buffer and have
the callers of this function freeing it when the lock is released.

The following backtrace was triggered by fstests generic/117.

  BUG: sleeping function called from invalid context at mm/vmalloc.c:2283
  in_atomic(): 1, irqs_disabled(): 0, pid: 649, name: fsstress
  4 locks held by fsstress/649:
   #0: 00000000a7478e7e (&type->s_umount_key#19){++++}, at: iterate_supers+0x77/0xf0
   #1: 00000000f8de1423 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: ceph_check_caps+0x7b/0xc60
   #2: 00000000562f2b27 (&s->s_mutex){+.+.}, at: ceph_check_caps+0x3bd/0xc60
   #3: 00000000f83ce16a (&mdsc->snap_rwsem){++++}, at: ceph_check_caps+0x3ed/0xc60
  CPU: 1 PID: 649 Comm: fsstress Not tainted 5.2.0+ torvalds#439
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014
  Call Trace:
   dump_stack+0x67/0x90
   ___might_sleep.cold+0x9f/0xb1
   vfree+0x4b/0x60
   ceph_buffer_release+0x1b/0x60
   __ceph_build_xattrs_blob+0x12b/0x170
   __send_cap+0x302/0x540
   ? __lock_acquire+0x23c/0x1e40
   ? __mark_caps_flushing+0x15c/0x280
   ? _raw_spin_unlock+0x24/0x30
   ceph_check_caps+0x5f0/0xc60
   ceph_flush_dirty_caps+0x7c/0x150
   ? __ia32_sys_fdatasync+0x20/0x20
   ceph_sync_fs+0x5a/0x130
   iterate_supers+0x8f/0xf0
   ksys_sync+0x4f/0xb0
   __ia32_sys_sync+0xa/0x10
   do_syscall_64+0x50/0x1c0
   entry_SYSCALL_64_after_hwframe+0x49/0xbe
  RIP: 0033:0x7fc6409ab617

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
frno7 pushed a commit that referenced this issue Sep 1, 2019
Calling ceph_buffer_put() in fill_inode() may result in freeing the
i_xattrs.blob buffer while holding the i_ceph_lock.  This can be fixed by
postponing the call until later, when the lock is released.

The following backtrace was triggered by fstests generic/070.

  BUG: sleeping function called from invalid context at mm/vmalloc.c:2283
  in_atomic(): 1, irqs_disabled(): 0, pid: 3852, name: kworker/0:4
  6 locks held by kworker/0:4/3852:
   #0: 000000004270f6bb ((wq_completion)ceph-msgr){+.+.}, at: process_one_work+0x1b8/0x5f0
   #1: 00000000eb420803 ((work_completion)(&(&con->work)->work)){+.+.}, at: process_one_work+0x1b8/0x5f0
   #2: 00000000be1c53a4 (&s->s_mutex){+.+.}, at: dispatch+0x288/0x1476
   #3: 00000000559cb958 (&mdsc->snap_rwsem){++++}, at: dispatch+0x2eb/0x1476
   #4: 000000000d5ebbae (&req->r_fill_mutex){+.+.}, at: dispatch+0x2fc/0x1476
   #5: 00000000a83d0514 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: fill_inode.isra.0+0xf8/0xf70
  CPU: 0 PID: 3852 Comm: kworker/0:4 Not tainted 5.2.0+ torvalds#441
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014
  Workqueue: ceph-msgr ceph_con_workfn
  Call Trace:
   dump_stack+0x67/0x90
   ___might_sleep.cold+0x9f/0xb1
   vfree+0x4b/0x60
   ceph_buffer_release+0x1b/0x60
   fill_inode.isra.0+0xa9b/0xf70
   ceph_fill_trace+0x13b/0xc70
   ? dispatch+0x2eb/0x1476
   dispatch+0x320/0x1476
   ? __mutex_unlock_slowpath+0x4d/0x2a0
   ceph_con_workfn+0xc97/0x2ec0
   ? process_one_work+0x1b8/0x5f0
   process_one_work+0x244/0x5f0
   worker_thread+0x4d/0x3e0
   kthread+0x105/0x140
   ? process_one_work+0x5f0/0x5f0
   ? kthread_park+0x90/0x90
   ret_from_fork+0x3a/0x50

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
enhancement New feature or request
Projects
None yet
Development

No branches or pull requests

1 participant