Comment 3 for bug 1390923

Created attachment 109158
Xorg.0.log with SNA option

Bug description:

Resume from suspend on Intel GM965/GL960 (GMA X3100) with DDX SNA fails and causes a reboot, but resume works fine if the non-default UXA DDX acceleration option is used.

System environment:

-- chipset: Intel GM965/GL960 (GMA X3100)
-- system architecture: 32-bit (i686)
-- xf86-video-intel: 2:2.99.910-0ubuntu1.1
-- xserver: 2:1.15.1-0ubuntu2.1
-- kernel: 3.13.0-39
-- Linux distribution: Mint 17 Quiana, Cinnamon, 32-bit
-- Machine or mobo model: Acer Extensa 5220, model: 5220-051G08Mi MS2205
-- Display connector: standard laptop lcd

Reproducing steps:

- trigger bug with Option "AccelMethod" "sna"and resume from suspend often causes reboot
- avoid bug with with Option "AccelMethod" "uxa" and resume from suspend seems reliable (no reboot noticed yet after several tests)

Example config to test with
/etc/X11/xorg.conf.d/20-intel.conf
  Section "Device"
     Identifier "Intel Graphics"
     Driver "intel"
     #Option "AccelMethod" "uxa"
     Option "AccelMethod" "sna"
  EndSection

Probability: Very frequent. I'd say only 1 in 10 resume attempts (with Option "AccelMethod" "sna") worked and the rest failed and caused a reboot.

Attempted to follow the guide here: https://01.org/linuxgraphics/documentation/how-debug-suspend-resume-issues-0
- resume from S3 suspend to RAM without mdm (display manager) running appeared to work fine, e.g. 'echo mem > /sys/power/state'
- the default suspend via menu GUI in Cinnamon often caused the resume bug to surface
- S4 hibernation worked fine and didn't seem to trigger the bug
- given the system reboots, unable to login via another terminal or ssh and cannot capture dmesg after, etc
- have not had time to try use intel_reg_dumper or intel_gpu_dump output

Found several similar bug reports for Intel 965 / X3100 type laptops and Intel drivers in Ubuntu 14.04 and or Kernel 3.13. My suspicion is newer Intel video drivers have caused a number of regressions in the latest Kernels, especially with older Intel Chipsets. These are similar bugs, but there fixes don't appear to work in my case:
- [TOSHIBA Satellite U400] suspend/resume failure: https://bugs.launchpad.net/ubuntu/+source/linux-meta/+bug/1290787
- [965gm regression v3.13] TOSHIBA Satellite U400 intel GM965/GL960 suspend/resume failure kernel 3.14 rc7, rc6, 3.13: https://bugs.freedesktop.org/show_bug.cgi?id=76520
- [Dell Inspiron 1525] Cannot resume from suspend: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1331654

Logged bug specific to Mint here, but realised this is quite probably an upstream bug and probably not specific to Mint: https://bugs.launchpad.net/ubuntu/+bug/1390923