#6532 NORM Never A: SD Card Corruption

[Zarro Boogs per Child]

#6532: SD Card Corruption
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 Reporter:  haralds    |       Owner:  rsmith        
     Type:  defect     |      Status:  new           
 Priority:  normal     |   Milestone:  Never Assigned
Component:  linuxbios  |     Version:                
 Keywords:             |    Verified:  0             
 Blocking:             |   Blockedby:                
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 It looks like some of the versions of current update.1 candidates and
 joyrides have serious problems with flash drives and SD cards. This
 especially effects ext 3 use.

 I first blamed cards, but even the good ones get clobbered.

 Some additional info:
 - As somebody else remarked, some of this appears to depend to some degree
 on the response time of the card or USB flash stick/adapter. Some cards I
 have do not work at all, but are fine in cameras an on OS X/WIN32.
 - Problem go from just corrupting the boot or super block to a whole range
 of blocks not being written to flash resulting in an unrecoverable disk.
 - This appears to be more of an issue with Joyride and update.1 candidate
 builds than the shipping version (656.)

 I seemed to have less trouble, when running from the SD card directly.
 Booting and running from NAND seemed to create the issue with external
 cards.

 I also noticed that power management did not seem to work/was disabled on
 651/656 (this is documented) and when running from the SD card on other
 builds. It was enabled in a number of experimental builds running from
 NAND. Could it be the power management is interfering with the SD/USB
 flash writes?

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Ticket URL: <http://dev.laptop.org/ticket/6532>
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