#10748 HIGH 11.2.0-: libertas crashes kernel in resume (was: Kernel hang in 11.2.0 os13)

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#10748: libertas crashes kernel in resume
---------------------------------+------------------------------------------
           Reporter:  greenfeld  |       Owner:  buytenh                          
               Type:  defect     |      Status:  new                              
           Priority:  high       |   Milestone:  11.2.0-M4                        
          Component:  kernel     |     Version:  Development build as of this date
         Resolution:             |    Keywords:                                   
        Next_action:  diagnose   |    Verified:  0                                
Deployment_affected:             |   Blockedby:                                   
           Blocking:             |  
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Comment(by dsd):

 Diagnosis so far:

 this crash is libertas-related, coming out of resume. Possibly related to
 wlan wakeup rather than other source (but we only have 1 log so far). also
 this line is suspect:

 {{{
 [ 5120.057540] libertas: EVENT: unknown event id 1
 }}}

 then we soon have a command timeout:

 {{{
 [ 5123.790089] libertas: command 0x000b timed out
 }}}

 one immediate suspicion is that this command was submitted before suspend,
 and the system wakes from resume waiting for a response. we know from
 previous experience that libertas isn't happy about this.

 command 0xb is CMD_802_11_GET_LOG triggered by the get_wireless_stats
 handler

 Enabling libertas debug would tell us more about when the command was
 submitted. unfortunately this was left out of current kernels, so i've
 enabled it for the next build.

 After that, we get command timeouts and while the system should then
 continue happily (perhaps without wireless) we get a kernel crash due to
 memory corruption - apparently theres a separate bug in libertas's command
 error handling code.

-- 
Ticket URL: <http://dev.laptop.org/ticket/10748#comment:2>
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