[syzbot] [hfs?] INFO: task hung in worker_thread (6)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 33a647c659ff Add linux-next specific files for 20260129
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=15aa1644580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1b94612779ae7173
dashboard link: https://syzkaller.appspot.com/bug?extid=fa1cc3e4b001b79309ec
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16cc1c52580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17849588580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9d0ce0a8fecd/disk-33a647c6.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4369620c4390/vmlinux-33a647c6.xz
kernel image: https://storage.googleapis.com/syzbot-assets/18ae695e8dfc/bzImage-33a647c6.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/20bb3c39107f/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+fa1cc3...@syzkaller.appspotmail.com

INFO: task kworker/u8:5:78 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:5 state:D stack:23136 pid:78 tgid:78 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x1539/0x5080 kernel/sched/core.c:6907
process_scheduled_works kernel/workqueue.c:3362 [inline]
worker_thread+0xb46/0x1140 kernel/workqueue.c:3443
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
1 lock held by khungtaskd/30:
#0:
ffffffff8e7601a0
(
){....}-{1:3}
ffff8880206a0148
(
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254
, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u8:3/49:
#0:
ffff8880206a0148
(
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254
#1:
ffffc90000ba7c40
((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255
#2: ffff88802b4f00e0 (&type->s_umount_key#55){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff88802b4f20b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u8:5/78:
#0: ffff8880206a0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254
#1: ffffc900025cfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x15a0 kernel/workqueue.c:3255
#2: ffff8880348a80e0 (&type->s_umount_key#55){.+.+}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff8880361ee0b0 (&tree->tree_lock){+.+.}-{4:4}, at: hfsplus_find_init+0x168/0x2d0 fs/hfsplus/bfind.c:28
4 locks held by kworker/u8:6/1143:
#0: ffff8880206a0148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x855/0x15a0 kernel/workqueue.c:3254


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