On Tue, Jun 26, 2012 at 03:08:32PM -0400, Giacomo Comes wrote: > I have a dell latitude E6420 with Sandybridge Mobile (GT2). > Since I got it (about one year ago), it has been a nightmare to run linux on it. > At the beginning I installed openSUSE 11.4 (kernel 2.6.37.6) and the laptop > would freeze almost immediately. After that I waited for newer kernels in order to > see if things would improve. They did improve indeed and finally with kernel 3.0 > I was able to run linux (openSUSE 11.4) without laptop freeze or screen issue. > Unfortunately, the only kernel that works with my laptop is 3.0. Newer kernel > (3.1, 3.2, 3.3 and 3.4) do not work. > This is what happen if I run kernel 2.6.39, 3.1, 3.2, 3.3 and 3.4: > The laptop boot and does the boot process fine. At the end of the boot process X > starts and here the problem appears (about 50% of the times): > the screen goes black on the left side (about 2/3 of the whole screen) with white > stripes to the right side (the remaining 1/3). > The laptop is not dead: I can remotely login or I can perform a clean shutdown > if I press the power button, but the screen is totally dead. > Another strange issue is that after a bad boot (with the black screen) at the > next reboot the screen will start to flicker. The flickering will last some time > and it will become less intense as the time goes until it will disappear completely. > The funny thing is that the intensity of flicker depends on how long I keep the > black screen. If, after the boot process, the black screen appears and I reboot > the laptop immediately, then the flicked is moderate and it disappear after > 1 or 2 minutes. If I keep the black screen for 1 minute or more, then after the > reboot the flicker is very intense and it takes much more to fade. > > Right now I run openSUSE 12.1 on the laptop, but I had to perform the following > trick: because openSUSE 12.1 ships with kernel 3.1, in order to make openSUSE run on my > laptop I have the options: > 1) downgrade to kernel 3.0 (I use 3.0.7) > 2) recompile the openSUSE kernel 3.1 replacing the directory drivers/gpu/drm/i915 > with the content of the same directory from kernel 3.0 source tree. > > I choose the second option as I can run the latest openSUSE kernel with patches > and fixes. > > I have searched google to see if other users have my same problem and > I have found few references to a problem similar to mine: > > http://lists.freedesktop.org/archives/intel-gfx/2011-March/009822.html > http://www.gossamer-threads.com/lists/linux/kernel/1474140 > https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/794474 > > But in none there is a mention on how to fix the problem. > > Is there any chance to improve the intel kernel driver to make it work > for my laptop as it was in kernel 3.0? Sure, we're always working to fix odd bugs ;-) > I can provide any information/testing as needed. A few things for you to do, pretty much random order: - Can you try out the latest drm-intel-next-queued branch from the drm-intel git repo at: http://cgit.freedesktop.org/~danvet/drm-intel This is the basic step to ensure that we haven't fixed your bug already in the latest code. - Please attach xrandr --verbos and full dmesg when booting with drm.debug=0xe (take a working kernel, doesn't matter that much). - If you can, please bisect which commit exactly introduced the regression betwen 3.0 and 3.1. That usually helps a _lot_ in tracking down these bugs. Yours, Daniel -- Daniel Vetter Mail: daniel at ffwll.ch Mobile: +41 (0)79 365 57 48
