[syzbot] [kernel?] WARNING in __vhost_task_wake

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: ae2d20002576 Add linux-next specific files for 20250917
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=149ec534580000
kernel config: https://syzkaller.appspot.com/x/.config?x=7dcbc33245a844f3
dashboard link: https://syzkaller.appspot.com/bug?extid=a1a3cefd6148c781117c
compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7c34033bfd08/disk-ae2d2000.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/5b001294bb15/vmlinux-ae2d2000.xz
kernel image: https://storage.googleapis.com/syzbot-assets/83d50ef44860/bzImage-ae2d2000.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a1a3ce...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: kernel/vhost_task.c:97 at __vhost_task_wake+0xbb/0xd0 kernel/vhost_task.c:97, CPU#1: syz.3.28/6112
Modules linked in:
CPU: 1 UID: 0 PID: 6112 Comm: syz.3.28 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__vhost_task_wake+0xbb/0xd0 kernel/vhost_task.c:97
Code: 38 00 74 08 48 89 df e8 93 81 95 00 48 8b 3b 5b 41 5e 41 5f e9 a6 45 01 00 e8 31 ef 30 00 90 0f 0b 90 eb 8b e8 26 ef 30 00 90 <0f> 0b 90 5b 41 5e 41 5f e9 18 47 f7 09 cc 0f 1f 80 00 00 00 00 90
RSP: 0018:ffffc9000b127a20 EFLAGS: 00010293
RAX: ffffffff818eed7a RBX: ffff8880563ff400 RCX: ffff88807e13bc80
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffffc9000b127af0 R08: ffff8880563ff477 R09: 1ffff1100ac7fe8e
R10: dffffc0000000000 R11: ffffed100ac7fe8f R12: 1ffff92001624f4c
R13: dffffc0000000000 R14: 0000000000000002 R15: dffffc0000000000
FS: 000055556f6ab500(0000) GS:ffff888125ae1000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9324bff000 CR3: 0000000028336000 CR4: 00000000003526f0
Call Trace:
<TASK>
vhost_worker_queue+0x194/0x260 drivers/vhost/vhost.c:253
__vhost_worker_flush+0x134/0x1e0 drivers/vhost/vhost.c:290
vhost_worker_flush drivers/vhost/vhost.c:303 [inline]
vhost_dev_flush drivers/vhost/vhost.c:313 [inline]
vhost_dev_stop+0x282/0x320 drivers/vhost/vhost.c:1178
vhost_vsock_dev_release+0x203/0x3f0 drivers/vhost/vsock.c:751
__fput+0x44c/0xa70 fs/file_table.c:468
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6e0278eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffe017861a8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007f6e029d7da0 RCX: 00007f6e0278eba9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f6e029d7da0 R08: 0000000000013868 R09: 0000001a0178649f
R10: 00007f6e029d7cb0 R11: 0000000000000246 R12: 000000000001c379
R13: 00007f6e029d6090 R14: ffffffffffffffff R15: 00007ffe017862c0
</TASK>


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