Re: [syzbot] [ext4?] WARNING: locking bug in ext4_move_extents

[Boqun Feng <boqun.feng@gmail.com>]

On Sun, Jun 04, 2023 at 08:53:02PM -0700, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    9561de3a55be Linux 6.4-rc5
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=14df9d7d280000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=7474de833c217bf4
> dashboard link: https://syzkaller.appspot.com/bug?extid=7f4a6f7f7051474e40ad
> compiler:       Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> Downloadable assets:
> disk image: https://storage.googleapis.com/syzbot-assets/661f38eebc53/disk-9561de3a.raw.xz
> vmlinux: https://storage.googleapis.com/syzbot-assets/d6c5afef083c/vmlinux-9561de3a.xz
> kernel image: https://storage.googleapis.com/syzbot-assets/7506eac4fc9d/bzImage-9561de3a.xz
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+7f4a6f7f7051474e40ad@syzkaller.appspotmail.com
> 
> ------------[ cut here ]------------
> Looking for class "&ei->i_data_sem" with key init_once.__key.780, but found a different class "&ei->i_data_sem" with the same key
> WARNING: CPU: 0 PID: 15140 at kernel/locking/lockdep.c:941 look_up_lock_class+0xc2/0x140 kernel/locking/lockdep.c:938
> Modules linked in:
> CPU: 0 PID: 15140 Comm: syz-executor.2 Not tainted 6.4.0-rc5-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/25/2023
> RIP: 0010:look_up_lock_class+0xc2/0x140 kernel/locking/lockdep.c:938
> Code: 8b 16 48 c7 c0 60 91 1e 90 48 39 c2 74 46 f6 05 5d 02 92 03 01 75 3d c6 05 54 02 92 03 01 48 c7 c7 a0 ae ea 8a e8 de 8a a3 f6 <0f> 0b eb 26 e8 f5 d0 80 f9 48 c7 c7 e0 ad ea 8a 89 de e8 37 ca fd
> RSP: 0018:ffffc9000356f410 EFLAGS: 00010046
> RAX: 9c96f62a5d44cf00 RBX: ffffffff9009a460 RCX: 0000000000040000
> RDX: ffffc9000cf9f000 RSI: 0000000000004e87 RDI: 0000000000004e88
> RBP: ffffc9000356f518 R08: ffffffff81530142 R09: ffffed1017305163
> R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
> R13: 1ffff920006ade90 R14: ffff888074763488 R15: ffffffff91cac681
> FS:  00007fe07ba3e700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000001b2d523000 CR3: 0000000021c7c000 CR4: 00000000003506f0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
>  <TASK>
>  register_lock_class+0x104/0x990 kernel/locking/lockdep.c:1290
>  __lock_acquire+0xd3/0x2070 kernel/locking/lockdep.c:4965
>  lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5705
>  down_write_nested+0x3d/0x50 kernel/locking/rwsem.c:1689
>  ext4_move_extents+0x37d/0xe40 fs/ext4/move_extent.c:621
>  __ext4_ioctl fs/ext4/ioctl.c:1352 [inline]
>  ext4_ioctl+0x3870/0x5b60 fs/ext4/ioctl.c:1608
>  vfs_ioctl fs/ioctl.c:51 [inline]
>  __do_sys_ioctl fs/ioctl.c:870 [inline]
>  __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
>  do_syscall_x64 arch/x86/entry/common.c:50 [inline]
>  do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
>  entry_SYSCALL_64_after_hwframe+0x63/0xcd
> RIP: 0033:0x7fe07ac8c169
> Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
> RSP: 002b:00007fe07ba3e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
> RAX: ffffffffffffffda RBX: 00007fe07adac120 RCX: 00007fe07ac8c169
> RDX: 0000000020000280 RSI: 00000000c028660f RDI: 0000000000000007
> RBP: 00007fe07ace7ca1 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007ffe5c49953f R14: 00007fe07ba3e300 R15: 0000000000022000
>  </TASK>
> 
> 
> ---
> This report is generated by a bot. It may contain errors.
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> 
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> 
> If the bug is already fixed, let syzbot know by replying with:
> #syz fix: exact-commit-title
> 
> If you want to change bug's subsystems, reply with:
> #syz set subsystems: new-subsystem
> (See the list of subsystem names on the web dashboard)
> 
> If the bug is a duplicate of another bug, reply with:
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> 
> If you want to undo deduplication, reply with:
> #syz undup

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/boqun/linux.git lockdep-for-tip