INFO: task syz.3.2120:12088 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.2120      state:D stack:28056 pid:12088 tgid:12087 ppid:7337   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 bdev_open+0xe0/0xd30
 blkdev_open+0x457/0x600
 do_dentry_open+0x953/0x13f0
 vfs_open+0x3b/0x340
 path_openat+0x2ee5/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f659ad8d510
RSP: 002b:00007f6598ff5b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000002400 RCX: 00007f659ad8d510
RDX: 0000000000002400 RSI: 00007f6598ff5c10 RDI: 00000000ffffff9c
RBP: 00007f6598ff5c10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f659afd6038 R14: 00007f659afd5fa0 R15: 00007fff1af3cd78
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e33d660 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
6 locks held by kworker/0:3/2324:
1 lock held by klogd/5284:
2 locks held by getty/5673:
 #0: ffff88810fc580a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000290e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by sshd/5828:
1 lock held by udevd/5845:
 #0: ffff888022533358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/5851:
 #0: ffff888107d54358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/5854:
 #0: ffff888107d55358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
3 locks held by kworker/u8:4/5875:
1 lock held by udevd/5956:
 #0: ffff8880219ef358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/5957:
 #0: ffff888022537358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
3 locks held by kworker/0:8/5973:
1 lock held by udevd/6399:
 #0: ffff88802236b358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/9364:
 #0: ffff88802236f358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/10138:
 #0: ffff888022433358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
6 locks held by kworker/0:1/10452:
 #0: ffff888104bef148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000913fba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff888023b7b198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff88803303b198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #4: ffff888038238160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #5: ffffffff8e1e2ab0 (umhelper_sem){++++}-{4:4}, at: usermodehelper_read_trylock+0xf0/0x2b0
1 lock held by udevd/10760:
 #0: ffff8880219eb358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/11401:
 #0: ffff888022513358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by udevd/11402:
 #0: ffff888022517358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
4 locks held by udevd/11404:
 #0: ffff888029f71790 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb7/0xe20
 #1: ffff888106e2a088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x5c/0x420
 #2: ffff888027669b48 (kn->active#30){++++}-{0:0}, at: kernfs_seq_start+0xb2/0x420
 #3: ffff88803303b198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0
1 lock held by syz.3.2120/12088:
 #0: ffff8880219eb358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.4.2259/12502:
 #0: ffff8880219ef358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz-executor/12688:
 #0: ffffffff8e3430f8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730
1 lock held by syz.7.2667/13708:
 #0: ffff888022533358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.8.2846/14260:
 #0: ffff888023b7b198 (&dev->mutex){....}-{4:4}, at: usbdev_open+0x16e/0x760
1 lock held by syz.5.2903/14438:
 #0: ffffffff8f7452c8 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 34 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full) 
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+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 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: 14434 Comm: syz.9.2902 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:unwind_next_frame+0x374/0x2390
Code: ea 48 01 d2 48 01 f2 48 bd 00 00 00 00 00 fc ff df 0f 84 37 01 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 6d 19 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f
RSP: 0018:ffffc900074bf538 EFLAGS: 00000a03
RAX: 0000000000000000 RBX: ffffffff8fdb0fa0 RCX: ffffffff8fdb0fa8
RDX: ffffffff9058bb12 RSI: ffffffff9058bb12 RDI: ffffffff8c0381a0
RBP: dffffc0000000000 R08: 0000000000000006 R09: ffffffff8173bd25
R10: ffffc900074bf658 R11: ffffffff81ac44a0 R12: ffffffff9058bb16
R13: ffffffff9058bb17 R14: ffffc900074bf608 R15: ffffffff8fdb0fa4
FS:  00007f75787ee6c0(0000) GS:ffff8880b83e0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556c52195150 CR3: 0000000027216000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 save_stack+0xf5/0x1f0
 __reset_page_owner+0x71/0x1f0
 __free_frozen_pages+0xbc4/0xd30
 vfree+0x25a/0x400
 kcov_close+0x28/0x50
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0xa0/0x790
 exit_to_user_mode_loop+0x75/0x130
 do_syscall_64+0x2bd/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f757a5c1465
Code: Unable to access opcode bytes at 0x7f757a5c143b.
RSP: 002b:00007f75787ebf50 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 0000000000000003 RCX: 00007f757a5c1465
RDX: 00007f75787ebf90 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 000000000000001a R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f75787ebfe8
R13: 0000200000000100 R14: 00007f757a7d5fa0 R15: 00007ffea57d7d78
 </TASK>
