XFS: Assertion failed: !rwsem_is_locked(&inode->i_rwsem)

During some xfstest runs on next-20180615 I hit the following with DAX + generic/388:

================================================
WARNING: lock held when returning to user space! 4.17.0-next-20180615-00001-gf09d99951966 #2 Not tainted
------------------------------------------------
fsstress/6598 is leaving the kernel with locks still held!
2 locks held by fsstress/6598:
#0: 00000000d8f89e14 (&sb->s_type->i_mutex_key#13){++++}, at: xfs_ilock+0x211/0x310 #1: 000000005cc93137 (&(&ip->i_mmaplock)->mr_lock){++++}, at: xfs_ilock+0x1eb/0x310
XFS: Assertion failed: !rwsem_is_locked(&inode->i_rwsem), file: fs/xfs/xfs_super.c, line: 966

------------[ cut here ]------------
kernel BUG at fs/xfs/xfs_message.c:102!
invalid opcode: 0000 [#1] PREEMPT SMP PTI
CPU: 5 PID: 6609 Comm: umount Not tainted 4.17.0-next-20180615-00001-gf09d99951966 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
RIP: 0010:assfail+0x2d/0x30
Code: 00 00 55 48 89 f1 41 89 d0 48 c7 c6 40 f1 59 82 48 89 fa 31 ff 48 89 e5 e8 50 f9 ff ff 80 3d 11 dc 37 01 00 75 04 0f 0b 5d c3 <0f> 0b 90 0f 1f 44 00 00 55 48 63 f6 49 89 f9 ba 01 00 00 00 41 b8
RSP: 0018:ffffc9000404bd28 EFLAGS: 00010202
RAX: 0000000000000000 RBX: ffff8800b65c4cc0 RCX: 0000000000000000
RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff825320e6
RBP: ffffc9000404bd28 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: f000000000000000 R12: ffff8800b65c4a40
R13: ffffffff822644e0 R14: ffffffff8258431b R15: ffff8801049331c0
FS:  00007f0bdbc8bfc0(0000) GS:ffff880114e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ff8b3060c8 CR3: 000000010ec9c000 CR4: 00000000000006e0
Call Trace:
 xfs_fs_destroy_inode+0x22a/0x300
 destroy_inode+0x3e/0x60
 evict+0x141/0x1a0
 dispose_list+0x56/0x80
 evict_inodes+0x15a/0x1b0
 generic_shutdown_super+0x44/0x120
 kill_block_super+0x27/0x50
 deactivate_locked_super+0x48/0x80
 deactivate_super+0x40/0x60
 cleanup_mnt+0x3f/0x80
 __cleanup_mnt+0x12/0x20
 task_work_run+0x8f/0xc0
 exit_to_usermode_loop+0xc2/0xd0
 do_syscall_64+0x211/0x220
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f0bdace21a7
Code: ad 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d c9 ac 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffefd64f788 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 000055ff8b2fc2d0 RCX: 00007f0bdace21a7
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 000055ff8b304960
RBP: 000055ff8b304960 R08: 0000000000000000 R09: 000055ff8b2fc010
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0bdba76184
R13: 0000000000000000 R14: 000055ff8b2fc4b0 R15: 0000000000000000
Modules linked in: nd_pmem dax_pmem device_dax nd_btt nfit libnvdimm
---[ end trace f46cb40cc37c4976 ]---

Message from syslogd@amonkhet-5 at Jun 18 13:50:34 ...
kernel:XFS: Assertion failed: !rwsem_is_locked(&inode->i_rwsem), file: fs/xfs/xfs_super.c, line: 966

I've run the test a bunch more times since then and haven't been able to reproduce the issue. I'm hoping that the above might be enough to be useful.

Thanks,
- Ross

What errors occurred before this? generic/388 is testing all sorts of error paths by randomly shutting down the filesystem, so it'e entirely possible that we've leaked those locks (XFS_IOLOCK and XFS_MMAPLOCK) on some rarely travelled error path. The prior errors might help identify that path.

As this is just a follow on issue at unmount where we expect the inode to be unlocked before tearing it down - it's just a messenger, not the smoking gun...

Cheers,

Dave.

Dave Chinner
[email protected]

Here is the full output from another reproduction:

Shell:

 FSTYP         -- xfs (debug)
 PLATFORM      -- Linux/x86_64 amonkhet-7 4.17.0-next-20180615
 MKFS_OPTIONS  -- -f -bsize=4096 /dev/pmem0p2

MOUNT_OPTIONS -- -o dax -o context=system_u:object_r:root_t:s0 /dev/pmem0p2 /mnt/xfstests_scratch

generic/388 71s ...
Message from syslogd@amonkhet-7 at Jun 19 10:19:18 ...
kernel:XFS: Assertion failed: !rwsem_is_locked(&inode->i_rwsem), file: fs/xfs/xfs_super.c, line: 966

Dmesg:
run fstests generic/388 at 2018-06-19 10:18:29
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Ending clean mount
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Ending clean mount
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_to_bp: xfs_trans_read_buf() returned error -5.
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0
XFS (pmem0p2): xfs_do_force_shutdown(0x1) called from line 222 of file fs/xfs/libxfs/xfs_defer.c. Return address = ffffffff8152d0f5 XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_do_force_shutdown(0x1) called from line 222 of file fs/xfs/libxfs/xfs_defer.c. Return address = ffffffff8152d0f5 XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): Unmounting Filesystem
XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
XFS (pmem0p2): Mounting V5 Filesystem
XFS (pmem0p2): Starting recovery (logdev: internal)
XFS (pmem0p2): Ending recovery (logdev: internal)
XFS (pmem0p2): xfs_imap_lookup: xfs_ialloc_read_agi() returned error -5, agno 0

================================================
WARNING: lock held when returning to user space!
4.17.0-next-20180615 #1 Not tainted
------------------------------------------------
fsstress/20108 is leaving the kernel with locks still held!
2 locks held by fsstress/20108:
#0: 00000000250ceb4d (&sb->s_type->i_mutex_key#13){++++}, at: xfs_ilock+0x211/0x310 #1: 000000003caf8c3b (&(&ip->i_mmaplock)->mr_lock){++++}, at: xfs_ilock+0x1eb/0x310
XFS: Assertion failed: !rwsem_is_locked(&inode->i_rwsem), file: fs/xfs/xfs_super.c, line: 966

 ------------[ cut here ]------------
 kernel BUG at fs/xfs/xfs_message.c:102!
 invalid opcode: 0000 [#1] PREEMPT SMP PTI
 CPU: 4 PID: 20148 Comm: umount Not tainted 4.17.0-next-20180615 #1
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014
 RIP: 0010:assfail+0x2d/0x30
 Code: 00 00 55 48 89 f1 41 89 d0 48 c7 c6 e8 f0 59 82 48 89 fa 31 ff 48 89 e5 e8 50 f9 ff ff 80 3d 11 dc 37 01 00 75 04 0f 0b 5d c3 <0f> 0b 90 0f 1f 44 00 00 55 48 63 f6 49 89 f9 ba 01 00 00 00 41 b8 
 RSP: 0018:ffffc90001253d28 EFLAGS: 00010202
 RAX: 0000000000000000 RBX: ffff8800b2d20940 RCX: 0000000000000000
 RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff825320a6
 RBP: ffffc90001253d28 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: f000000000000000 R12: ffff8800b2d206c0
 R13: ffffffff822644a0 R14: ffffffff825842c3 R15: ffff8800b2d216c0
 FS:  00007fb3326a9fc0(0000) GS:ffff880114c00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00005589e96bdb58 CR3: 0000000035aca000 CR4: 00000000000006e0
 Call Trace:
  xfs_fs_destroy_inode+0x22a/0x300
  destroy_inode+0x3e/0x60
  evict+0x141/0x1a0
  dispose_list+0x56/0x80
  evict_inodes+0x15a/0x1b0
  generic_shutdown_super+0x44/0x120
  kill_block_super+0x27/0x50
  deactivate_locked_super+0x48/0x80
  deactivate_super+0x40/0x60
  cleanup_mnt+0x3f/0x80
  __cleanup_mnt+0x12/0x20
  task_work_run+0x8f/0xc0
  exit_to_usermode_loop+0xc2/0xd0
  do_syscall_64+0x211/0x220
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 RIP: 0033:0x7fb3317001a7
 Code: ad 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d c9 ac 2b 00 f7 d8 64 89 01 48 
 RSP: 002b:00007ffdaace4b08 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
 RAX: 0000000000000000 RBX: 00005636e2b472d0 RCX: 00007fb3317001a7
 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 00005636e2b4f960
 RBP: 00005636e2b4f960 R08: 0000000000000000 R09: 00005636e2b47010
 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb332494184
 R13: 0000000000000000 R14: 00005636e2b474b0 R15: 0000000000000000
 Modules linked in: nd_pmem nd_btt dax_pmem device_dax nfit libnvdimm
 ---[ end trace 89eff31b76d71280 ]---
 RIP: 0010:assfail+0x2d/0x30
 Code: 00 00 55 48 89 f1 41 89 d0 48 c7 c6 e8 f0 59 82 48 89 fa 31 ff 48 89 e5 e8 50 f9 ff ff 80 3d 11 dc 37 01 00 75 04 0f 0b 5d c3 <0f> 0b 90 0f 1f 44 00 00 55 48 63 f6 49 89 f9 ba 01 00 00 00 41 b8 
 RSP: 0018:ffffc90001253d28 EFLAGS: 00010202
 RAX: 0000000000000000 RBX: ffff8800b2d20940 RCX: 0000000000000000
 RDX: 00000000ffffffc0 RSI: 000000000000000a RDI: ffffffff825320a6
 RBP: ffffc90001253d28 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: f000000000000000 R12: ffff8800b2d206c0
 R13: ffffffff822644a0 R14: ffffffff825842c3 R15: ffff8800b2d216c0
 FS:  00007fb3326a9fc0(0000) GS:ffff880114c00000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00005589e96bdb58 CR3: 0000000035aca000 CR4: 00000000000006e0

- Ross

....

Ok, nothing extra to go on there. can you get lockdep to dump the stack or oops so we at least know what syscall was being run when this is detected?

Cheers,

Dave.

Dave Chinner
[email protected]

Well, I can't seem to reproduce this reliably anymore. :(

I did reproduce it once with the debug you requested, and the syscall that wsa being run when we found the lock imbalance was __x64_sys_ioctl, for whatever that's worth.