#12466 NORM 4-firmw: SKU295 one-off hang in Open Firmware after Linux reboot

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#12466: SKU295 one-off hang in Open Firmware after Linux reboot
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           Reporter:  Quozl                |       Owner:  Quozl               
               Type:  defect               |      Status:  assigned            
           Priority:  normal               |   Milestone:  4-firmware          
          Component:  ofw - open firmware  |     Version:  Development firmware
         Resolution:                       |    Keywords:                      
        Next_action:  test in build        |    Verified:  0                   
Deployment_affected:                       |   Blockedby:                      
           Blocking:                       |  
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Changes (by Quozl):

  * owner:  wmb at firmworks.com => Quozl
  * status:  new => assigned
  * next_action:  diagnose => test in build


Comment:

 The cause was corruption of heap when an allocation occurs, and the
 allocator is interrupted by an alarm handler which also makes an
 allocation.  The allocator is apparently not re-entrant, and the results
 are either the same address returned to both callers, or corruption of the
 linked list.

 http://dev.laptop.org/~quozl/q7b14ja.rom has a potential fix, which:
  * allocates from heap during driver open rather than during an alarm
 handler, for the /ap-sp, /keyboard, and /usb/keyboard drivers,
  * turns on the storage LED during the keyboard alarm handler,
  * enters the debugger if a key is pressed on the serial port while the
 SDHCI driver is waiting for a command to complete.

-- 
Ticket URL: <http://dev.laptop.org/ticket/12466#comment:2>
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