[v6.6] WARNING in blkdev_flush_mapping

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: aa0e49877a2e Linux 6.6.148
git tree: linux-6.6.y
console output: https://syzkaller.appspot.com/x/log.txt?x=117893b9580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f0bc3d90c30838b5
dashboard link: https://syzkaller.appspot.com/bug?extid=ffcc586d4c44d8a17e46
compiler: Debian clang version 22.1.8 (++20260613092233+e80beda6e255-1~exp1~20260613092250.77), Debian LLD 22.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f83b390cfc1f/disk-aa0e4987.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/1d4bdb338edd/vmlinux-aa0e4987.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3f57c1d51ee3/bzImage-aa0e4987.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+ffcc58...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 1 PID: 5965 at block/bdev.c:643 blkdev_flush_mapping+0xac/0x290 block/bdev.c:643
Modules linked in:
CPU: 1 PID: 5965 Comm: syz.0.24 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:blkdev_flush_mapping+0xac/0x290 block/bdev.c:643
Code: 42 80 3c 28 00 74 08 4c 89 f7 e8 af d0 cd fd 49 8b 3e 48 ba ff ff ff ff ff ff ff 7f 31 f6 e8 cb 5d a3 fd eb 11 e8 24 4e 75 fd <0f> 0b 48 85 db 75 9f e8 18 4e 75 fd 48 89 1c 24 4c 8d b3 80 00 00
RSP: 0018:ffffc9000b3afcb8 EFLAGS: 00010293
RAX: ffffffff8412235c RBX: ffff888020290000 RCX: ffff88802dd75a00
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: 0000000000000002 R08: ffff88802029003b R09: 1ffff11004052007
R10: dffffc0000000000 R11: ffffed1004052008 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffff888020290134 R15: ffff888020290038
FS: 000055557753f500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc813311e8 CR3: 000000002d018000 CR4: 00000000003506e0
Call Trace:
<TASK>
blkdev_put_whole block/bdev.c:676 [inline]
blkdev_put+0x49a/0x7a0 block/bdev.c:954
blkdev_release+0x84/0x90 block/fops.c:604
__fput+0x221/0x940 fs/file_table.c:418
task_work_run+0x1d4/0x260 kernel/task_work.c:245
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7feebdb9e019
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffeccc686c8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffeccc687b0 RCX: 00007feebdb9e019
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000016168 R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b2cd20000 R11: 0000000000000246 R12: 00007ffeccc687f0
R13: 00007feebde25fac R14: 00000000000162ae R15: 00007feebde25fa0
</TASK>


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