#11220 NORM 1.75-so: Probe ext4 corruption

[Zarro Boogs per Child]

#11220: Probe ext4 corruption
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 Reporter:  martin.langhoff  |                 Owner:  martin.langhoff
     Type:  task             |                Status:  new            
 Priority:  normal           |             Milestone:  1.75-software  
Component:  distro           |               Version:  not specified  
 Keywords:                   |           Next_action:  never set      
 Verified:  0                |   Deployment_affected:                 
Blockedby:                   |              Blocking:                 
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 We've seen Jon Nettleton hit some disk corruption repeatedly on his
 development/test machine. Diagnosis of the prob led us to #11210 but it is
 unclear whether that is the issue.

 This is one of our current risks -- it is a concern because we need to
 know real soon whether this is a hw issue (related to the eMMC parts) or
 not. We have hit corruption issues with ext4 in the past (#9513) and fell
 back to ext3. It is not clear however that ext4 is suspect: the whole
 11.2.0 dev cycle was done under ext4 and no disk corruption incidents were
 reported AFAIK.

 Jon seemed to hit it while:

 * developing, compiling,
 * using an ext SD card in the slot,
 * running a patched kernel and xorg
 * presumably crashing a lot

 We need to consider action around this

 * try to force the error -- I'll set up a test rig for this, applying
 unclean shutdowns on a couple of SKU198 units
 * keep our eyes open for disk corruption reports, specially in builds
 including the new gfx code
 * be prepared to switch back to ext3

-- 
Ticket URL: <http://dev.laptop.org/ticket/11220>
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