#10009 NORM Not Tri: OFW page fault while looping runin test

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#10009: OFW page fault while looping runin test
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           Reporter:  pgf                  |       Owner:  wmb at firmworks.com                 
               Type:  defect               |      Status:  assigned                          
           Priority:  normal               |   Milestone:  Not Triaged                       
          Component:  ofw - open firmware  |     Version:  Development source as of this date
         Resolution:                       |    Keywords:                                    
        Next_action:  never set            |    Verified:  0                                 
Deployment_affected:                       |   Blockedby:                                    
           Blocking:                       |  
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Changes (by wmb at firmworks.com):

  * status:  new => assigned


Comment:

 We have duplicated this problem many times.  The symptom is always that a
 set of pages that should be mapped via the page tables is not mapped,
 despite evidence that the mmu "map" method was duly called for those
 pages.

 The mapping in question is for the SPI FLASH, mapped for the purpose of
 reading icon images from dropin modules.

 In some cases, the "translations" entry for those pages is present, in
 other cases it is not.  When the translations entry is present, the page
 fault occurs at virtual address ffe6xxxx (supposed to map to fff6xxxx).
 When it is not present, the fault is at VA ffe1.0000 (supposed to map to
 PA fff10000).

 Attempts to reproduce by repetitive OFW "bye"s have failed, but doing the
 runin tests on a 3-minute cycle then reboot do reproduce it.

 Using EC version 1.9.22, which has a longer reset time, does not fix the
 problem.

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Ticket URL: <http://dev.laptop.org/ticket/10009#comment:1>
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