[Bug 57926] [Sandybridge Mobile (GT2+)] [Regression] Stretched output on LVDS1 after undocking external monitors during suspend

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=57926

Thilo-Alexander Ginkel <thilo at ginkel.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEEDINFO                    |NEW

--- Comment #7 from Thilo-Alexander Ginkel <thilo at ginkel.com> ---
Hm... Strange as it may sound I am not able to fix the issue by reverting to an
older kernel version. So far I tried 3.2.x (current Ubuntu Kernel), 3.0.55 and
3.1.4.

So while I am certain that this worked in the past it may not be related to the
kernel version.

BTW, the register dump attached is already based on the bad state.

Fortunately, during testing I figured out that it is possible to simplify the
reproduction steps:

Suspend/resume is not required. Undocking is not required. Just make sure to:
1. Boot with the external displays attached
2. Run the following sequence:
   xrandr -d :0.0 --output LVDS1 --off --output HDMI3 --mode 1600x1200 \
     --primary --auto
   sleep 5
   xrandr -d :0.0 --output HDMI2 --mode 1600x1200 --right-of HDMI3 --auto
   xrandr -d :0.0 --output HDMI2 --off
   sleep 5
   xrandr -d :0.0 --output LVDS1 --mode 1600x900 --auto
   sleep 5
   xrandr -d :0.0 --output HDMI3 --off

=> The display will show up stretched.

What will, however, reliably prevent the issue is to boot with the external
monitors being detached and only attaching them after boot. Would a register
dump captured for this scenario help to figure out what's different?

Just in case it helps I have captured a kernel log with drm.debug=0x06 set.

Any ideas?

-- 
You are receiving this mail because:
You are the QA Contact for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20121207/72d06f4a/attachment-0001.html>