[syzbot] [bcachefs?] INFO: task hung in bch2_fallocate_dispatch

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 56fb6f92854f Merge tag 'drm-next-2024-05-25' of https://gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1566f392980000
kernel config: https://syzkaller.appspot.com/x/.config?x=34e05c35ec964e75
dashboard link: https://syzkaller.appspot.com/bug?extid=0527f53d2da9f65d41cb
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/99e44ece48d2/disk-56fb6f92.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2997a3e91a46/vmlinux-56fb6f92.xz
kernel image: https://storage.googleapis.com/syzbot-assets/3f788e8712a0/bzImage-56fb6f92.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0527f5...@syzkaller.appspotmail.com

INFO: task syz-executor.1:11146 blocked for more than 143 seconds.
Not tainted 6.9.0-syzkaller-12277-g56fb6f92854f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1 state:D stack:26640 pid:11146 tgid:11124 ppid:10161 flags:0x00000006
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_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
__down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
inode_lock include/linux/fs.h:791 [inline]
bch2_fallocate_dispatch+0x295/0x3810 fs/bcachefs/fs-io.c:774
vfs_fallocate+0x564/0x6c0 fs/open.c:330
do_vfs_ioctl+0x2592/0x2e50 fs/ioctl.c:886


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