Vladimír Kriška, if you would like a fix integrated into Ubuntu, then yes, you would want to follow the instructions previously requested of you.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to xorg in Ubuntu. https://bugs.launchpad.net/bugs/1403275 Title: i915 display driver causes crash back to login window Status in xorg package in Ubuntu: Incomplete Bug description: I've just installed Ubuntu 14.04 server on Dell Latitude E7440 and then installed Cinnamon 2.4.5 on top of it. The laptop has an external monitor connected through Display Port and a docking station. On the first day the system worked perfectly. On the second day, the system booted to the login screen (leaving the external screen empty but otherwise seemed to be under X11's control), it then let me type my username and password but then X exits, shows a bit of VT1 with errors then gets back to the login page. I found the following error in /var/log/kern.log: [drm:intel_dp_complete_link_train] ERROR failed to train DP, aborting I found a page which claims to solve this error for 12.04 in the second comment in https://www.libreoffice.org/bugzilla/show_bug.cgi?id=73694#c2. I found that the file linux- source-3.13.0/drivers/gpu/drm/i915/intel_dp.c, which is included in the tar file /usr/src/linux-source-3.13.0.tar.bz2 (also copied in /usr/src/linux-source-3.13.0/linux-source-3.13.0.tar.bz2), from the kernel source package "linux-source-3.13.0", contains the pre-patch lines mentioned in the fix above. Would you please consider including this fix in the Ubuntu kernel? Thanks, --Amos For completeness, the patch pointed to from the link above is: Link: https://www.libreoffice.org/bugzilla/attachment.cgi?id=92231 diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 8f17f8fbd0b1..5631cfb874db 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -847,8 +847,8 @@ intel_dp_compute_config(struct intel_encoder *encoder, mode_rate = intel_dp_link_required(adjusted_mode->crtc_clock, bpp); - for (clock = 0; clock <= max_clock; clock++) { - for (lane_count = 1; lane_count <= max_lane_count; lane_count <<= 1) { + for (lane_count = 1; lane_count <= max_lane_count; lane_count <<= 1) { + for (clock = 0; clock <= max_clock; clock++) { link_clock = drm_dp_bw_code_to_link_rate(bws[clock]); link_avail = intel_dp_max_data_rate(link_clock, lane_count); ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: xorg 1:7.7+1ubuntu8 ProcVersionSignature: Ubuntu 3.13.0-43.72-generic 3.13.11.11 Uname: Linux 3.13.0-43-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.6 Architecture: amd64 CurrentDesktop: X-Cinnamon Date: Wed Dec 17 12:57:10 2014 InstallationDate: Installed on 2014-12-15 (1 days ago) InstallationMedia: Ubuntu-Server 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.3) SourcePackage: xorg Symptom: display Title: Xorg crash UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1403275/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
