INFO: task syz.0.7556:31274 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.7556      state:D stack:28184 pid:31274 tgid:31272 ppid:25657  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7fe/0x1300
 bdev_open+0xe0/0xd30
 blkdev_open+0x470/0x610
 do_dentry_open+0x7ce/0x1420
 vfs_open+0x3b/0x340
 path_openat+0x3486/0x3e20
 do_filp_open+0x22d/0x490
 do_sys_openat2+0x12f/0x220
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ffa3275b58e
RSP: 002b:00007ffa33703b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ffa337046c0 RCX: 00007ffa3275b58e
RDX: 0000000000008000 RSI: 00007ffa33703c00 RDI: ffffffffffffff9c
RBP: 00007ffa33703c00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: cccccccccccccccd
R13: 00007ffa32a16128 R14: 00007ffa32a16090 R15: 00007ffd08160b48
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e35a360 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5652:
 #0: ffff88811554c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by sshd/5811:
3 locks held by kworker/1:5/5897:
 #0: ffff888100075948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc900056c7bc0 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
 #2: ffff88816cda3240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x202/0x3d0
2 locks held by kworker/0:7/8764:
 #0: ffff888100075948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc90003cd7bc0 (key_gc_work){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
1 lock held by syz.8.7099/29869:
 #0: ffffffff8e360c78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770
1 lock held by udevd/30725:
 #0: ffff88810a8d0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.0.7556/31274:
 #0: ffff88810a8d0358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.2.7657/31546:
 #0: ffff88810a8d0358 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x27e/0x470
2 locks held by kworker/u10:9/1577:
 #0: ffff888168b59148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc900050c7bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
2 locks held by kworker/u10:19/1583:
 #0: ffff888168b59148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0
 #1: ffffc90005137bc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0
1 lock held by dhcpcd/3757:
 #0: ffff888104bae260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0
1 lock held by dhcpcd/3758:
 #0: ffff88811139e260 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcd0

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xf90/0xfe0
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3657 Comm: syz.7.8873 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:rcu_is_watching+0x3a/0xb0
Code: e8 4b c2 d0 09 89 c3 83 f8 08 73 65 49 bf 00 00 00 00 00 fc ff df 4c 8d 34 dd d0 ed d7 8d 4c 89 f0 48 c1 e8 03 42 80 3c 38 00 <74> 08 4c 89 f7 e8 dc 9e 81 00 48 c7 c3 d8 f6 d0 92 49 03 1e 48 89
RSP: 0018:ffffc90005f3f498 EFLAGS: 00000246
RAX: 1ffffffff1bafdba RBX: 0000000000000000 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8be74be0 RDI: ffffffff8be74ba0
RBP: ffffffff8174c105 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90005f3f678 R11: ffffffff81ae5d00 R12: 0000000000000002
R13: ffffffff8e35a360 R14: ffffffff8dd7edd0 R15: dffffc0000000000
FS:  00005555838a1500(0000) GS:ffff88818e324000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fff115f9b58 CR3: 0000000114cd8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0x5f/0x330
 unwind_next_frame+0xc2/0x23c0
 arch_stack_walk+0x11b/0x150
 stack_trace_save+0xa9/0x100
 save_stack+0x122/0x230
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xbb9/0xd10
 vfree+0x25a/0x400
 kcov_close+0x28/0x50
 __fput+0x44f/0xa70
 task_work_run+0x1d9/0x270
 do_exit+0x69b/0x2310
 do_group_exit+0x21b/0x2d0
 get_signal+0x1284/0x1330
 arch_do_signal_or_restart+0xbc/0x830
 exit_to_user_mode_loop+0x86/0x480
 do_syscall_64+0x2b7/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fab0399acb9
Code: Unable to access opcode bytes at 0x7fab0399ac8f.
RSP: 002b:00007ffe10d1a048 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffdfc RBX: 00000000001114aa RCX: 00007fab0399acb9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fab03c15fac
RBP: 0000000000000bea R08: 3fffffffffffffff R09: 0000000000000000
R10: 00007ffe10d1a150 R11: 0000000000000246 R12: 00007ffe10d1a170
R13: 00007fab03c15fac R14: 0000000000112094 R15: 00007ffe10d1a150
 </TASK>
