INFO: task kworker/u4:0:8 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/u4:0 state:D stack:24088 pid: 8 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>
INFO: task kworker/u4:8:13127 blocked for more than 144 seconds.
Not tainted 5.16.0-rc1-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:8 state:D stack:24304 pid:13127 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:
2 locks held by kworker/u4:0/8:
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
#1: ffffc90000cd7db0 ((work_completion)(&nbd->remove_work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
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
3 locks held by kworker/u4:2/44:
3 locks held by kworker/u4:4/290:
1 lock held by systemd-udevd/2968:
1 lock held by in:imklog/6227:
#0: ffff888077e80d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990
1 lock held by syz-executor.4/9454:
#0: ffff88801ab83360 (&lo->lo_mutex){+.+.}-{3:3}, at: __loop_clr_fd+0x7a/0x1070 drivers/block/loop.c:1106
2 locks held by kworker/0:9/10735:
2 locks held by kworker/u4:8/13127:
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:635 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:662 [inline]
#0: ffff8881472e2138 ((wq_completion)nbd-del){+.+.}-{0:0}, at: process_one_work+0x896/0x1690 kernel/workqueue.c:2269
#1: ffffc9000387fdb0 ((work_completion)(&nbd->remove_work)){+.+.}-{0:0}, at: process_one_work+0x8ca/0x1690 kernel/workqueue.c:2273
4 locks held by kworker/0:18/23431:
2 locks held by agetty/4154:
#0: ffff88801a4d4098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252
#1: ffffc90002bb32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113
1 lock held by syz-executor.1/4603:
#0: ffffffff8bbf7f28 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x23/0xf0 kernel/trace/trace_event_perf.c:241
1 lock held by syz-executor.0/4619:
=============================================
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: 23431 Comm: kworker/0:18 Not tainted 5.16.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_power_efficient gc_worker
RIP: 0010:mark_lock+0x6/0x17b0 kernel/locking/lockdep.c:4566
Code: ff c3 66 90 be 00 00 02 00 48 c7 c7 e0 a6 2b 8f e8 df b3 7b 02 48 98 c3 66 66 2e 0f 1f 84 00 00 00 00 00 90 41 57 41 56 41 55 <41> 54 41 89 d4 48 ba 00 00 00 00 00 fc ff df 55 53 48 81 ec 18 01
RSP: 0018:ffffc9000be67c10 EFLAGS: 00000002
RAX: 0000000000000004 RBX: 0000000000000000 RCX: 1ffffffff1b228e9
RDX: 0000000000000002 RSI: ffff888022dfe160 RDI: ffff888022dfd700
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff817e2bc8 R11: 0000000000000000 R12: ffff888022dfd700
R13: dffffc0000000000 R14: ffff888022dfe160 R15: 0000000000002ec7
FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002021b030 CR3: 000000003b038000 CR4: 0000000000350ef0
DR0: 0080ffff00000000 DR1: 0080ffff00000000 DR2: 0080ffff00000000
DR3: 0080ffff00000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
mark_held_locks+0x9f/0xe0 kernel/locking/lockdep.c:4206
__trace_hardirqs_on_caller kernel/locking/lockdep.c:4224 [inline]
lockdep_hardirqs_on_prepare kernel/locking/lockdep.c:4292 [inline]
lockdep_hardirqs_on_prepare+0x135/0x400 kernel/locking/lockdep.c:4244
trace_hardirqs_on+0x5b/0x1c0 kernel/trace/trace_preemptirq.c:49
seqcount_lockdep_reader_access include/linux/seqlock.h:105 [inline]
nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:326 [inline]
gc_worker+0xb4f/0x1030 net/netfilter/nf_conntrack_core.c:1441
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: ff c3 inc %ebx
2: 66 90 xchg %ax,%ax
4: be 00 00 02 00 mov $0x20000,%esi
9: 48 c7 c7 e0 a6 2b 8f mov $0xffffffff8f2ba6e0,%rdi
10: e8 df b3 7b 02 callq 0x27bb3f4
15: 48 98 cltq
17: c3 retq
18: 66 66 2e 0f 1f 84 00 data16 nopw %cs:0x0(%rax,%rax,1)
1f: 00 00 00 00
23: 90 nop
24: 41 57 push %r15
26: 41 56 push %r14
28: 41 55 push %r13
* 2a: 41 54 push %r12 <-- trapping instruction
2c: 41 89 d4 mov %edx,%r12d
2f: 48 ba 00 00 00 00 00 movabs $0xdffffc0000000000,%rdx
36: fc ff df
39: 55 push %rbp
3a: 53 push %rbx
3b: 48 rex.W
3c: 81 .byte 0x81
3d: ec in (%dx),%al
3e: 18 01 sbb %al,(%rcx)