INFO: task kworker/u4:7:9543 blocked for more than 143 seconds.
Not tainted 5.16.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:7 state:D stack:23888 pid: 9543 ppid: 2 flags:0x00004000
Workqueue: nbd-del nbd_dev_remove_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:4972 [inline]
__schedule+0xa9a/0x4940 kernel/sched/core.c:6253
schedule+0xd2/0x260 kernel/sched/core.c:6326
blk_mq_freeze_queue_wait+0x112/0x160 block/blk-mq.c:178
del_gendisk+0x598/0x860 block/genhd.c:623
nbd_dev_remove+0x3c/0xf0 drivers/block/nbd.c:252
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8bb83a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458
1 lock held by systemd-udevd/2969:
1 lock held by in:imklog/6214:
#0: ffff88801d5ee5f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
2 locks held by rs:main Q:Reg/6215:
#0: ffff8880b9d39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478
#1: ffff8880b9d279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x3a6/0x490 kernel/sched/psi.c:880
1 lock held by syz-executor.0/6541:
#0: ffff88807e25c460 (sb_writers#5){.+.+}-{0:0}, at: do_unlinkat+0x17f/0x650 fs/namei.c:4146
2 locks held by kworker/u4:7/9543:
#0: ffff88801a8bf938 ((wq_completion)nbd-del){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff88801a8bf938 ((wq_completion)nbd-del){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff88801a8bf938 ((wq_completion)nbd-del){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff88801a8bf938 ((wq_completion)nbd-del){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
#0: ffff88801a8bf938 ((wq_completion)nbd-del){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
#0: ffff88801a8bf938 ((wq_completion)nbd-del){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
#1: ffffc9000435fdb0 ((work_completion)(&nbd->remove_work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
2 locks held by kworker/u4:0/9795:
1 lock held by syz-executor.3/3184:
#0: ffff8880b9c39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478
1 lock held by syz-executor.3/3210:
#0: ffffffff8c8109c8 (ubi_devices_mutex){+.+.}-{3:3}, at: ctrl_cdev_ioctl+0x2db/0x390 drivers/mtd/ubi/cdev.c:1042
1 lock held by syz-executor.5/3197:
1 lock held by syz-executor.4/3212:
1 lock held by syz-executor.2/3217:
#0:
ffffffff8c8109c8
(
ubi_devices_mutex
){+.+.}-{3:3}
, at: ctrl_cdev_ioctl+0x2db/0x390 drivers/mtd/ubi/cdev.c:1042
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xc1d/0xf50 kernel/hung_task.c:295
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 9795 Comm: kworker/u4:0 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_release kernel/locking/lockdep.c:5325 [inline]
RIP: 0010:lock_release+0x25f/0x720 kernel/locking/lockdep.c:5657
Code: 00 00 48 8d 7b 22 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 01 38 d0 7c 08 84 d2 <0f> 85 47 04 00 00 66 f7 43 22 f0 ff 74 36 48 8d 7b 20 48 b8 00 00
RSP: 0018:ffffc9000291fbc8 EFLAGS: 00000046
RAX: 0000000000000003 RBX: ffff88802396e1b0 RCX: ffffc9000291fc18
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88802396e1d2
RBP: 1ffff92000523f7b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8bb83a60
R13: 0000000000000003 R14: ffff88802396e158 R15: ffff88802396d700
FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2131cb8080 CR3: 0000000022241000 CR4: 0000000000350ef0
Call Trace:
<TASK>
rcu_lock_release include/linux/rcupdate.h:273 [inline]
rcu_read_unlock include/linux/rcupdate.h:721 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:416 [inline]
batadv_nc_worker+0x86b/0xfa0 net/batman-adv/network-coding.c:723
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 48 8d 7b 22 lea 0x22(%rbx),%rdi
6: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax
d: fc ff df
10: 48 89 fa mov %rdi,%rdx
13: 48 c1 ea 03 shr $0x3,%rdx
17: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx
1b: 48 89 f8 mov %rdi,%rax
1e: 83 e0 07 and $0x7,%eax
21: 83 c0 01 add $0x1,%eax
24: 38 d0 cmp %dl,%al
26: 7c 08 jl 0x30
28: 84 d2 test %dl,%dl
* 2a: 0f 85 47 04 00 00 jne 0x477 <-- trapping instruction
30: 66 f7 43 22 f0 ff testw $0xfff0,0x22(%rbx)
36: 74 36 je 0x6e
38: 48 8d 7b 20 lea 0x20(%rbx),%rdi
3c: 48 rex.W
3d: b8 .byte 0xb8