[v6.1] INFO: task hung in exfat_sync_fs

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 32c9cdbe383c Linux 6.1.60
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=13156b85680000
kernel config: https://syzkaller.appspot.com/x/.config?x=c022d971b9287d2b
dashboard link: https://syzkaller.appspot.com/bug?extid=0d1cb0a990ed164d3874
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a490a5ba6b9d/disk-32c9cdbe.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/2c65d1af9e04/vmlinux-32c9cdbe.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d262499bca4d/Image-32c9cdbe.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0d1cb0...@syzkaller.appspotmail.com

INFO: task syz-executor.4:5416 blocked for more than 143 seconds.
Not tainted 6.1.60-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:0 pid:5416 ppid:4266 flags:0x0000000d
Call trace:
__switch_to+0x320/0x754 arch/arm64/kernel/process.c:553
context_switch kernel/sched/core.c:5241 [inline]
__schedule+0xee4/0x1c98 kernel/sched/core.c:6554
schedule+0xc4/0x170 kernel/sched/core.c:6630
schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6689
__mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
exfat_sync_fs+0x6c/0x108 fs/exfat/super.c:65
sync_fs_one_sb+0xd8/0x120 fs/sync.c:84
iterate_supers+0x124/0x1dc fs/super.c:746
ksys_sync+0xd4/0x1cc fs/sync.c:104
__arm64_sys_sync+0x14/0x24 fs/sync.c:113
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffff8000159e4d70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
#0: ffff8000159e5570 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/28:
#0: ffff8000159e4ba0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:305
3 locks held by kworker/0:3/3806:
#0: ffff0000c0020d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265
#1: ffff800020297c20 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267
#2: ffff800015894510 (umhelper_sem){++++}-{3:3}, at: usermodehelper_read_lock_wait+0x138/0x244 kernel/umh.c:250
2 locks held by getty/3981:
#0: ffff0000d606c098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
#1: ffff80001bcb02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1214 drivers/tty/n_tty.c:2188
2 locks held by syz-executor.0/4269:
3 locks held by syz-executor.1/29010:
3 locks held by syz-executor.5/29080:
5 locks held by kworker/1:17/29919:
#0: ffff0000c4668d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265
#1: ffff800030587c20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267
#2: ffff0000d17aa190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:836 [inline]
#2: ffff0000d17aa190 (&dev->mutex){....}-{3:3}, at: hub_event+0x1ac/0x4360 drivers/usb/core/hub.c:5758
#3: ffff0000d5653190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:836 [inline]
#3: ffff0000d5653190 (&dev->mutex){....}-{3:3}, at: usb_disconnect+0xec/0x7b0 drivers/usb/core/hub.c:2237
#4: ffff0000c46fb118 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:836 [inline]
#4: ffff0000c46fb118 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1080 [inline]
#4: ffff0000c46fb118 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xbc/0x724 drivers/base/dd.c:1283
2 locks held by kworker/u4:1/3912:
#0: ffff0000c0029138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265
#1: ffff800021e17c20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267
2 locks held by kworker/u4:2/4724:
#0: ffff0000c0029138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2265
#1: ffff8000304c7c20 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2267
2 locks held by syz-executor.4/5416:
#0: ffff0001227620e0 (&type->s_umount_key#93){++++}-{3:3}, at: iterate_supers+0xb0/0x1dc fs/super.c:744
#1: ffff0001247020e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_sync_fs+0x6c/0x108 fs/exfat/super.c:65
1 lock held by udevd/5465:
#0: ffff0001b4596598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:537 [inline]
#0: ffff0001b4596598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1354 [inline]
#0: ffff0001b4596598 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1644 [inline]
#0: ffff0001b4596598 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2c4/0x1c98 kernel/sched/core.c:6471
1 lock held by syz-executor.2/8422:
1 lock held by modprobe/8423:
1 lock held by syz-executor.3/8427:
1 lock held by syz-executor.5/8425:
#0: ffff0001b4576598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:537 [inline]
#0: ffff0001b4576598 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock kernel/sched/sched.h:1354 [inline]
#0: ffff0001b4576598 (&rq->__lock){-.-.}-{2:2}, at: rq_lock kernel/sched/sched.h:1644 [inline]
#0: ffff0001b4576598 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0x2c4/0x1c98 kernel/sched/core.c:6471
2 locks held by syz-executor.5/8428:
2 locks held by modprobe/8426:
1 lock held by syz-executor.1/8430:

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