[v6.1] INFO: task hung in flush_old_commits

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3b29299e5f60 Linux 6.1.22
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=144f8bb9c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=bbb9a1f6f7f5a1d9
dashboard link: https://syzkaller.appspot.com/bug?extid=1402b2dbcd2d308b6f11
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2affbd06cbfd/disk-3b29299e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/8b22d1baf827/vmlinux-3b29299e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/d5e3891c88bf/Image-3b29299e.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1402b2...@syzkaller.appspotmail.com

INFO: task kworker/0:0:24770 blocked for more than 143 seconds.
Not tainted 6.1.22-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:0 state:D stack:0 pid:24770 ppid:2 flags:0x00000008
Workqueue: events_long flush_old_commits
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
reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
reiserfs_sync_fs fs/reiserfs/super.c:76 [inline]
flush_old_commits+0x1b0/0x2b8 fs/reiserfs/super.c:111
process_one_work+0x7ac/0x1404 kernel/workqueue.c:2289
worker_thread+0x8e4/0xfec kernel/workqueue.c:2436
kthread+0x24c/0x2d4 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860
INFO: task syz-executor.3:4144 blocked for more than 143 seconds.
Not tainted 6.1.22-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:0 pid:4144 ppid:4368 flags:0x00000001
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
reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
reiserfs_setattr+0x46c/0x101c fs/reiserfs/inode.c:3284
notify_change+0xc24/0xec0 fs/attr.c:482
do_truncate+0x1c0/0x28c fs/open.c:65
handle_truncate fs/namei.c:3216 [inline]
do_open fs/namei.c:3561 [inline]
path_openat+0x1fa0/0x2548 fs/namei.c:3714
do_filp_open+0x1bc/0x3cc fs/namei.c:3741
do_sys_openat2+0x128/0x3d8 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1337
__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:581
INFO: task syz-executor.3:4148 blocked for more than 143 seconds.
Not tainted 6.1.22-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:0 pid:4148 ppid:4368 flags:0x00000001
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
rwsem_down_write_slowpath+0xc80/0x156c kernel/locking/rwsem.c:1189
__down_write_common kernel/locking/rwsem.c:1314 [inline]
__down_write kernel/locking/rwsem.c:1323 [inline]
down_write+0x84/0x88 kernel/locking/rwsem.c:1574
inode_lock include/linux/fs.h:756 [inline]
do_truncate+0x1ac/0x28c fs/open.c:63
handle_truncate fs/namei.c:3216 [inline]
do_open fs/namei.c:3561 [inline]
path_openat+0x1fa0/0x2548 fs/namei.c:3714
do_filp_open+0x1bc/0x3cc fs/namei.c:3741
do_sys_openat2+0x128/0x3d8 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1337
__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:581
INFO: task syz-executor.3:4153 blocked for more than 143 seconds.
Not tainted 6.1.22-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:0 pid:4153 ppid:4368 flags:0x00000001
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
rwsem_down_write_slowpath+0xc80/0x156c kernel/locking/rwsem.c:1189
__down_write_common kernel/locking/rwsem.c:1314 [inline]
__down_write kernel/locking/rwsem.c:1323 [inline]
down_write+0x84/0x88 kernel/locking/rwsem.c:1574
inode_lock include/linux/fs.h:756 [inline]
generic_file_write_iter+0x88/0x2b4 mm/filemap.c:3911
call_write_iter include/linux/fs.h:2205 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x610/0x914 fs/read_write.c:584
ksys_write+0x15c/0x26c fs/read_write.c:637
__do_sys_write fs/read_write.c:649 [inline]
__se_sys_write fs/read_write.c:646 [inline]
__arm64_sys_write+0x7c/0x90 fs/read_write.c:646
__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:581
INFO: task syz-executor.3:4156 blocked for more than 143 seconds.
Not tainted 6.1.22-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:0 pid:4156 ppid:4368 flags:0x00000001
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
rwsem_down_write_slowpath+0xc80/0x156c kernel/locking/rwsem.c:1189
__down_write_common kernel/locking/rwsem.c:1314 [inline]
__down_write kernel/locking/rwsem.c:1323 [inline]
down_write+0x84/0x88 kernel/locking/rwsem.c:1574
inode_lock include/linux/fs.h:756 [inline]
do_truncate+0x1ac/0x28c fs/open.c:63
handle_truncate fs/namei.c:3216 [inline]
do_open fs/namei.c:3561 [inline]
path_openat+0x1fa0/0x2548 fs/namei.c:3714
do_filp_open+0x1bc/0x3cc fs/namei.c:3741
do_sys_openat2+0x128/0x3d8 fs/open.c:1310
do_sys_open fs/open.c:1326 [inline]
__do_sys_openat fs/open.c:1342 [inline]
__se_sys_openat fs/open.c:1337 [inline]
__arm64_sys_openat+0x1f0/0x240 fs/open.c:1337
__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:581

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffff800015754a30 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
#0: ffff800015755230 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
#0: ffff800015754860 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:305
2 locks held by getty/3995:
#0: ffff0000d40a7098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
#1: ffff80001ca102f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1210 drivers/tty/n_tty.c:2177
1 lock held by syz-fuzzer/4459:
4 locks held by kworker/0:0/24770:
#0: ffff0000c0021538 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2262
#1:
ffff80001f577c20 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2264
#2: ffff0000c98700e0 (&type->s_umount_key#67){++++}-{3:3}, at: flush_old_commits+0xcc/0x2b8 fs/reiserfs/super.c:97
#3: ffff0000cf9a7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
4 locks held by kworker/0:3/2770:
#0: ffff0000c0021538 ((wq_completion)events_long){+.+.}-{0:0}, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2262
#1: ffff80002c0e7c20 ((work_completion)(&(&sbi->old_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2264
#2: ffff00014074c0e0 (&type->s_umount_key#67){++++}-{3:3}, at: flush_old_commits+0xcc/0x2b8 fs/reiserfs/super.c:97
#3: ffff0000da22c090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
3 locks held by syz-executor.3/4122:
3 locks held by syz-executor.3/4144:
#0: ffff0000c9870460 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
#2: ffff0000cf9a7090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
2 locks held by syz-executor.3/4148:
#0: ffff0000c9870460 (sb_writers#20){.+.+}-{0:0}
, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1:
ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
3 locks held by syz-executor.3/4153:
#0: ffff0000d5f81268 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xd8/0x104 fs/file.c:1047
#1: ffff0000c9870460 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x244/0x914 fs/read_write.c:580
#2: ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#2: ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: generic_file_write_iter+0x88/0x2b4 mm/filemap.c:3911
2 locks held by syz-executor.3/4156:
#0: ffff0000c9870460 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff0000dfe74520 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
3 locks held by syz-executor.1/5072:
3 locks held by syz-executor.1/5092:
#0: ffff00014074c460 (sb_writers
#20){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
#2: ffff0000da22c090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
2 locks held by syz-executor.1/5095:
#0: ffff00014074c460 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
2 locks held by syz-executor.1/5099:
#0: ffff00014074c460 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x44/0x9c fs/namespace.c:393
#1: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#1: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: do_truncate+0x1ac/0x28c fs/open.c:63
3 locks held by syz-executor.1/5100:
#0: ffff0000d1a019e8 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xd8/0x104 fs/file.c:1047
#1: ffff00014074c460 (sb_writers#20){.+.+}-{0:0}, at: vfs_write+0x244/0x914 fs/read_write.c:580
#2: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:756 [inline]
#2: ffff000156905260 (&sb->s_type->i_mutex_key#27){+.+.}-{3:3}, at: generic_file_write_iter+0x88/0x2b4 mm/filemap.c:3911

=============================================



---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: fa74641fb6b9 Linux 6.1.29
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=179ced0e280000
kernel config: https://syzkaller.appspot.com/x/.config?x=7454aa89ac475d7b

dashboard link: https://syzkaller.appspot.com/bug?extid=1402b2dbcd2d308b6f11
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=124491d9280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1672afce280000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/53e4da6b145c/disk-fa74641f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/adeb1a2cfa86/vmlinux-fa74641f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c976f1155d08/Image-fa74641f.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/e44d96baf4b4/mount_1.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+1402b2...@syzkaller.appspotmail.com

INFO: task kworker/0:0:7 blocked for more than 143 seconds.
Not tainted 6.1.29-syzkaller #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:kworker/0:0 state:D stack:0 pid:7 ppid:2 flags:0x00000008

Workqueue: events_long flush_old_commits

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
reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27
reiserfs_sync_fs fs/reiserfs/super.c:76 [inline]
flush_old_commits+0x1b0/0x2b8 fs/reiserfs/super.c:111
process_one_work+0x7ac/0x1404 kernel/workqueue.c:2289
worker_thread+0x8e4/0xfec kernel/workqueue.c:2436

kthread+0x250/0x2d8 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:860

Showing all locks held in the system:

4 locks held by kworker/0:0/7:
#0:
ffff0000c0021538
(
(wq_completion)events_long

){+.+.}-{0:0}
, at: process_one_work+0x664/0x1404 kernel/workqueue.c:2262
#1:

ffff800019b47c20
(
(work_completion)(&(&sbi->old_work)->work)

){+.+.}-{0:0}
, at: process_one_work+0x6a8/0x1404 kernel/workqueue.c:2264
#2:

ffff0000d537e0e0 (
&type->s_umount_key
#39

){++++}-{3:3}
, at: flush_old_commits+0xcc/0x2b8 fs/reiserfs/super.c:97
#3:

ffff0000d58ed090
(
&sbi->lock

){+.+.}-{3:3}
, at: reiserfs_write_lock+0x7c/0xe8 fs/reiserfs/lock.c:27

1 lock held by rcu_tasks_kthre/12:
#0:

ffff800015774ef0
(
rcu_tasks.tasks_gp_mutex

){+.+.}-{3:3}
, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
#0:

ffff8000157756f0
(
rcu_tasks_trace.tasks_gp_mutex

){+.+.}-{3:3}
, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
#0:

ffff800015774d20
(
rcu_read_lock

){....}-{1:2}
, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:305

2 locks held by getty/3976:
#0:
ffff0000d0cce098
(
&tty->ldisc_sem

){++++}-{0:0}
, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
#1:

ffff80001ca202f0
(
&ldata->atomic_read_lock

){+.+.}-{3:3}
, at: n_tty_read+0x414/0x1210 drivers/tty/n_tty.c:2177

6 locks held by syz-executor930/4253:

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