#10680 HIGH Gen2: XO-1.75 A2 has CPU faults when heavily loaded (was: XO-1.75 A2 has CPU faults when simultaneously using WLAN and SD)

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#10680: XO-1.75 A2 has CPU faults when heavily loaded
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           Reporter:  wad       |       Owner:  wad          
               Type:  defect    |      Status:  assigned     
           Priority:  high      |   Milestone:  Gen2         
          Component:  hardware  |     Version:  1.75-A2      
         Resolution:            |    Keywords:  XO-1.75, XO-3
        Next_action:  diagnose  |    Verified:  0            
Deployment_affected:            |   Blockedby:               
           Blocking:            |  
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Comment(by wad):

 The "full" test that I've been running is:

 - Start the laptop, and after Linux boots login to Gnome

 - Establish a WiFi network connection

 - Install the NAND tests and memtester if they aren't already (see above)

 - Get and install the nettest and jpegtest functions:

  wget dev.laptop.org/~wad/nettest

  wget dev.laptop.org/~wad/jpegtest

  chmod a+x *test

 - Open a terminal (Applications -> System -> Terminal) and run:

  sudo memtester 100M

 - Open another terminal (<CTL><SHIFT>N) and run:

  sudo /nand/test.sh

 - Open another terminal and run:

  ./jpegtest

 - If you have a good network connection, or have modified the script (see
 below), open another terminal and run:

  ./nettest

 On laptops with their Vmain voltage set properly, none of these test
 processes should generate any errors, with the possible exception of the
 eMMC test scripts...  None of these processes should quit with a
 segmentation or illegal instruction fault, and there should be no kernel
 crashes.

 You should modify the nettest script to use a file (any file, preferably
 in the 1 to 10 MB size range) from a server local to you.  Just edit the
 TESTFILE string to point to the new file.  If you don't, nettest will
 continuously download a 10MB from OLPC's servers, pausing for 2 seconds
 between downloads!

 If the network interface loses association during the test, nettest will
 start generating errors.  This is not necessarily a problem with the
 hardware, but can reflect NetworkManager's behavior in a hostile RF
 environment.  If you can reassociate and restart the test without
 rebooting, and there aren't any dire error messages in /var/log/messages,
 then it isn't the problem this ticket is tracking.

 Likewise, you will find it necessary to edit /etc/X11/xorg.conf to change
 the fourth line turning on the ShadowFB to:

    Option   "ShadowFB"    "false"

 If you don't, X will crash (#10686).  Even if you are using the virtual
 terminals (<CTL><ALT>Group, etc.), X crashing will still cause the network
 connection to be dropped.

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Ticket URL: <http://dev.laptop.org/ticket/10680#comment:6>
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