audit: type=1400 audit(2000000899.159:80115): avc:  denied  { map } for  pid=30795 comm="modprobe" path="/lib/x86_64-linux-gnu/libc-2.13.so" dev="sda1" ino=2784 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1
BUG: workqueue lockup - pool cpus=0 node=0 flags=0x1 nice=0 stuck for 147s!
Showing busy workqueues and worker pools:
workqueue events: flags=0x0
  pwq 2: cpus=1 node=0 flags=0x1 nice=0 active=8/256
    in-flight: 9552:key_garbage_collector
    pending: free_user_ns, free_user_ns, free_user_ns, free_user_ns, free_user_ns, free_user_ns, free_user_ns
  pwq 0: cpus=0 node=0 flags=0x1 nice=0 active=5/256
    in-flight: 25693:linkwatch_event
    pending: wait_rcu_exp_gp, vmstat_shepherd, vmpressure_work_fn, free_obj_work
workqueue events_unbound: flags=0x2
  pwq 4: cpus=0-1 flags=0x4 nice=0 active=5/512
    in-flight: 27489:call_usermodehelper_exec_work, 11882:call_usermodehelper_exec_work, 11876:call_usermodehelper_exec_work, 27496:call_usermodehelper_exec_work, 11870:call_usermodehelper_exec_work

======================================================
WARNING: possible circular locking dependency detected
4.14.115+ #64 Not tainted
------------------------------------------------------
ksoftirqd/0/7 is trying to acquire lock:
 (console_owner){-.-.}, at: [<00000000c6550117>] log_next kernel/printk/printk.c:492 [inline]
 (console_owner){-.-.}, at: [<00000000c6550117>] console_unlock+0x28e/0xc60 kernel/printk/printk.c:2378

but task is already holding lock:
 (&pool->lock/1){..-.}, at: [<00000000974931dc>] show_workqueue_state kernel/workqueue.c:4518 [inline]
 (&pool->lock/1){..-.}, at: [<00000000974931dc>] show_workqueue_state.cold+0x22f/0xe95 kernel/workqueue.c:4491

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #3 (&pool->lock/1){..-.}:

-> #2 (&(&port->lock)->rlock){-.-.}:

-> #1 (&port_lock_key){-.-.}:

-> #0 (console_owner){-.-.}:

other info that might help us debug this:

Chain exists of:
  console_owner --> &(&port->lock)->rlock --> &pool->lock/1

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&pool->lock/1);
                               lock(&(&port->lock)->rlock);
                               lock(&pool->lock/1);
  lock(console_owner);

 *** DEADLOCK ***

4 locks held by ksoftirqd/0/7:
 #0:  (kernel/workqueue.c:5442){+.-.}, at: [<00000000cd788502>] lockdep_copy_map include/linux/lockdep.h:174 [inline]
 #0:  (kernel/workqueue.c:5442){+.-.}, at: [<00000000cd788502>] call_timer_fn+0xc6/0x680 kernel/time/timer.c:1269
 #1:  (rcu_read_lock_sched){....}, at: [<00000000fea3d0f3>] show_workqueue_state+0x0/0x100 kernel/workqueue.c:4390
 #2:  (&pool->lock/1){..-.}, at: [<00000000974931dc>] show_workqueue_state kernel/workqueue.c:4518 [inline]
 #2:  (&pool->lock/1){..-.}, at: [<00000000974931dc>] show_workqueue_state.cold+0x22f/0xe95 kernel/workqueue.c:4491
 #3:  (console_lock){+.+.}, at: [<00000000822bac7b>] console_trylock_spinning kernel/printk/printk.c:1644 [inline]
 #3:  (console_lock){+.+.}, at: [<00000000822bac7b>] vprintk_emit+0x11a/0x330 kernel/printk/printk.c:1916

stack backtrace:
CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 4.14.115+ #64
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x10e lib/dump_stack.c:53
 print_circular_bug.isra.0.cold+0x2dc/0x425 kernel/locking/lockdep.c:1258
workqueue events_power_efficient: flags=0x80
  pwq 0: cpus=0 node=0 flags=0x1 nice=0 active=1/256
    pending: neigh_periodic_work
workqueue mm_percpu_wq: flags=0x8
  pwq 0: cpus=0 node=0 flags=0x1 nice=0 active=2/256 MAYDAY
    pending: vmstat_update, drain_local_pages_wq BAR(31183)
workqueue netns: flags=0xe000a
  pwq 4: cpus=0-1 flags=0x4 nice=0 active=1/1
    in-flight: 32291:cleanup_net
workqueue ipv6_addrconf: flags=0x40008
  pwq 0: cpus=0 node=0 flags=0x1 nice=0 active=1/1
    in-flight: 73(RESCUER):addrconf_verify_work
pool 0: cpus=0 node=0 flags=0x1 nice=0 hung=148s workers=2 manager: 22
pool 2: cpus=1 node=0 flags=0x1 nice=0 hung=0s workers=4 manager: 30773 idle: 29580 8077
pool 4: cpus=0-1 flags=0x4 nice=0 hung=29s workers=12 idle: 11874 27446 27469 9561 9510 32323
INFO: task kworker/0:0:25693 blocked for more than 140 seconds.
      Not tainted 4.14.115+ #64
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:0     D28672 25693      2 0x80000000
Workqueue: events linkwatch_event
Call Trace:
 schedule+0x92/0x1c0 kernel/sched/core.c:3498
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3556
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x559/0x1430 kernel/locking/mutex.c:893
 linkwatch_event+0xa/0x50 net/core/link_watch.c:236