INFO: task syz-executor:14726 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21832 pid:14726 tgid:14726 ppid:1      task_flags:0x400140 flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x9a/0x270
 wait_for_completion+0x2bf/0x5d0
 kthread_stop+0x194/0x5c0
 bch2_copygc_stop+0x4b/0x120
 __bch2_fs_read_only+0x47/0x5b0
 bch2_fs_read_only+0x42a/0xb00
 __bch2_fs_stop+0x100/0x900
 generic_shutdown_super+0x135/0x2c0
 bch2_kill_sb+0x41/0x50
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2dbb38ff17
RSP: 002b:00007fff7bfe6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f2dbb411c05 RCX: 00007f2dbb38ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff7bfe60e0
RBP: 00007fff7bfe60e0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff7bfe7170
R13: 00007f2dbb411c05 R14: 000000000005d284 R15: 00007fff7bfe71b0
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
1 lock held by khungtaskd/35:
 #0: ffffffff8e139f20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u11:0/54:
1 lock held by dhcpcd/5595:
 #0: ffffffff8f538c48 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x323/0x1b50
2 locks held by getty/5681:
 #0: ffff88810dfb20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900026782f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by syz-executor/14726:
 #0: ffff88802439e0e0 (&type->s_umount_key#91){++++}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffff88812ec00278 (&c->state_lock){++++}-{4:4}, at: __bch2_fs_stop+0xf8/0x900
9 locks held by syz-executor/18539:
 #0: ffff888020f42428 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x211/0xb30
 #1: ffff88802403f088 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1e0/0x4f0
 #2: ffff8881082e2a58 (kn->active#48){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x203/0x4f0
 #3: ffffffff8edaf688 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x360
 #4: ffff888123ae00e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb6/0x800
 #5: ffff888123ae2250 (&devlink->lock_key#15){+.+.}-{4:4}, at: nsim_drv_remove+0x50/0x160
 #6: ffffffff8f538c48 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0xe5/0x670
 #7: ffff888127e10d30 (&dev_instance_lock_key#20){+.+.}-{4:4}, at: unregister_netdevice_many_notify+0xdf5/0x1ff0
 #8: ffffffff8e13f9b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730
3 locks held by syz.3.2152/18672:
5 locks held by syz.1.2153/18705:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 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+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 18705 Comm: syz.1.2153 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:asm_sysvec_apic_timer_interrupt+0x0/0x20
Code: 56 ac 79 0a e9 61 06 00 00 90 f3 0f 1e fa 0f 1f 00 fc 6a ff e8 11 05 00 00 48 89 c4 48 89 e7 e8 66 ab 79 0a e9 41 06 00 00 90 <f3> 0f 1e fa 0f 1f 00 fc 6a ff e8 f1 04 00 00 48 89 c4 48 89 e7 e8
RSP: 0018:ffffc900067ded78 EFLAGS: 00000046
RAX: ffffffff81a02717 RBX: ffffffff81a025d4 RCX: 0000000000080000
RDX: ffffc9002a802000 RSI: 000000000007ffff RDI: ffffffff8e12e1c0
RBP: ffffc900067deeb0 R08: ffffffff8fa39037 R09: 1ffffffff1f47206
R10: dffffc0000000000 R11: fffffbfff1f47207 R12: dffffc0000000000
R13: 1ffff92000cfbdb8 R14: 0000000000000200 R15: 000000000000002f
FS:  00007f3b549f66c0(0000) GS:ffff8881a3c18000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b4a7ff000 CR3: 00000000344a8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
RIP: 0010:vprintk_emit+0x58f/0x7a0
Code: 85 32 01 00 00 e8 11 87 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 00 87 1f 00 eb 06 e8 f9 86 1f 00 fb 48 c7 c7 c0 e1 12 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 b9 35
RSP: 0018:ffffc900067deda0 EFLAGS: 00000246
 _printk+0xcf/0x120
 set_capacity_and_notify+0x208/0x2d0
 loop_set_size+0x44/0xb0
 loop_configure+0x9f4/0xe50
 lo_ioctl+0x810/0x1c10
 blkdev_ioctl+0x5a8/0x6d0
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3b53b8e7eb
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007f3b549f5dc0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f3b53b8e7eb
RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000004424
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f3b549f5ef0 R14: 00007f3b549f5eb0 R15: 00007f3b49800000
 </TASK>
