[syzbot] [bcachefs?] INFO: task hung in bch2_copygc_stop

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e0cce98fe279 Merge tag 'tpmdd-next-6.10-rc2' of git://git...
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1783e2fc980000
kernel config: https://syzkaller.appspot.com/x/.config?x=47d282ddffae809f
dashboard link: https://syzkaller.appspot.com/bug?extid=c6fd966ebbdea1e8ff08
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/830865207351/disk-e0cce98f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2b2afbee0859/vmlinux-e0cce98f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a2eaac9c0eb1/bzImage-e0cce98f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+c6fd96...@syzkaller.appspotmail.com

INFO: task syz-executor.0:28112 blocked for more than 143 seconds.
Not tainted 6.10.0-rc1-syzkaller-00021-ge0cce98fe279 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0 state:D stack:20592 pid:28112 tgid:28112 ppid:1 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x1796/0x49d0 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_timeout+0xb0/0x310 kernel/time/timer.c:2557
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x355/0x620 kernel/sched/completion.c:148
kthread_stop+0x19e/0x630 kernel/kthread.c:710
bch2_copygc_stop+0x4f/0x150 fs/bcachefs/movinggc.c:399
__bch2_fs_read_only+0x47/0x430 fs/bcachefs/super.c:266
bch2_fs_read_only+0xb52/0x1210 fs/bcachefs/super.c:356
__bch2_fs_stop+0x105/0x540 fs/bcachefs/super.c:613
generic_shutdown_super+0x136/0x2d0 fs/super.c:642
bch2_kill_sb+0x41/0x50 fs/bcachefs/fs.c:2026
deactivate_locked_super+0xc4/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1267
task_work_run+0x24f/0x310 kernel/task_work.c:180
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x168/0x370 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89


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