Re: [PATCH] device probe: add self triggered delayed work request

[Shamir Rabinovitch]

Hi Qing,

I suspect there is potential dead-lock with this patch:

cpu0                                                    cpu1

driver_deferred_probe_add                               deferred_probe_work_func
 ...                                                     
mutex_unlock(&deferred_probe_mutex)
 mutex_lock(&deferred_probe_mutex)                        bus_probe_device(dev)
  ...                                                      device return 
-EPROBE_DEFER
  ...                                                       
driver_deferred_probe_add
  ...                                                        
mutex_lock(&deferred_probe_mutex)
  ...                                                         <deadlock!>
  cancel_delayed_work(&deferred_probe_trigger_work)
   <work will never end - deadlock!>

Please confirm if this scenario is possible.

BR, Shamir Rabinovitch