Re: WARNING in io_disable_sqo_submit

[Pavel Begunkov]

On 15/01/2021 23:08, syzbot wrote:
> Hello,
> 
> syzbot found the following issue on:
> 
> HEAD commit:    7c53f6b6 Linux 5.11-rc3
> git tree:       upstream
> console output: https://syzkaller.appspot.com/x/log.txt?x=12a76f70d00000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=c60c9ff9cc916cbc
> dashboard link: https://syzkaller.appspot.com/bug?extid=2f5d1785dc624932da78
> compiler:       gcc (GCC) 10.1.0-syz 20200507
> 
> Unfortunately, I don't have any reproducer for this issue yet.
> 
> IMPORTANT: if you fix the issue, please add the following tag to the commit:
> Reported-by: syzbot+2f5d1785dc624932da78@xxxxxxxxxxxxxxxxxxxxxxxxx
> 
> ------------[ cut here ]------------
> WARNING: CPU: 1 PID: 9094 at fs/io_uring.c:8884 io_disable_sqo_submit+0x106/0x130 fs/io_uring.c:8884

This one is a false positive warn_once, I'll fix it up


> Modules linked in:
> CPU: 1 PID: 9094 Comm: syz-executor.5 Not tainted 5.11.0-rc3-syzkaller #0
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> RIP: 0010:io_disable_sqo_submit+0x106/0x130 fs/io_uring.c:8884
> Code: b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 1d 83 8b 14 01 00 00 01 48 89 ef 5b 5d e9 ef bc 23 07 e8 5a e5 9a ff <0f> 0b e9 35 ff ff ff e8 3e a1 dd ff eb dc e8 67 a1 dd ff e9 65 ff
> RSP: 0018:ffffc9000188fea0 EFLAGS: 00010212
> RAX: 0000000000000044 RBX: ffff888079dbe000 RCX: ffffc90013b54000
> RDX: 0000000000040000 RSI: ffffffff81d7e466 RDI: ffff888079dbe0d0
> RBP: ffff8880201c0c80 R08: 0000000000000000 R09: 00000000278d0001
> R10: ffffffff81d7e705 R11: 0000000000000001 R12: ffff888079dbe000
> R13: ffff8880278d0001 R14: ffff888079dbe040 R15: ffff888079dbe0d0
> FS:  00007fe461a71700(0000) GS:ffff8880b9f00000(0000) knlGS:0000000000000000
> CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 0000000000000080 CR3: 0000000011fd1000 CR4: 0000000000350ee0
> Call Trace:
>  io_uring_flush+0x28b/0x3a0 fs/io_uring.c:9099
>  filp_close+0xb4/0x170 fs/open.c:1280
>  close_fd+0x5c/0x80 fs/file.c:626
>  __do_sys_close fs/open.c:1299 [inline]
>  __se_sys_close fs/open.c:1297 [inline]
>  __x64_sys_close+0x2f/0xa0 fs/open.c:1297
>  do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> RIP: 0033:0x45e219
> Code: 0d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 db b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007fe461a70c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
> RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000045e219
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
> RBP: 000000000119bfb0 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 000000000119bf8c
> R13: 00007ffc626b58ff R14: 00007fe461a719c0 R15: 000000000119bf8c

-- 
Pavel Begunkov