Kernel Bug Tracker – Bug 58021
[BISECTED] nouveau, nv50: External VGA not detected anymore
Last modified: 2013-06-20 07:40:23 UTC
Created attachment 101211 [details]
dmesg for last good commit
I have a lenove thinkpad T61p with a NVIDIA Corporation G84GLM [Quadro FX 570M].
When connecting my external VGA monitor my monitor is no more detected properly:
> cat /sys/class/drm/card0-VGA-1/status
gives now "disconnected"
Last good commit is
drm/nv50/disp: call into core to handle dac/sor power state changes
First bad commit is
drm/nv50/disp: call into core for dac load detection
The responsible function is
nv50_dac_detect in drivers/gpu/drm/nouveau/nv50_dac.c (moved to drivers/gpu/drm/nouveau/nv50_display.c in more recent kernels).
Also tried a 3.9.1 kernel. The problem still remains.
However, replacing nv50_dac_detect with the corresponding version from the last good commit fixed the problem (tried a 3.8.10 kernel).
Created attachment 101221 [details]
dmesg for first bad commit
I seem to have much of the same problem.
I am running a Dell desktop with NVIDA Quadro NVS 295 graphic card and two identical Dell monitors attache via DisplayPort.
I run Fedora 18 with all latest updates and using Nouveau drivers.
Starting with Kernel 3.8.11 it boots OK and both monitors works as expected.
Starting with Kernel 3.9.2, 3.9.3 or 3.9.4 boots and when trying to display anything on monitor two it gets into problems.
It boots until its tries to start the Xorg server and then monitor 2 starts flickering on and off. Monitor 1 stays with the boot logo of fedora.
Also during boot when booting I only have the boot logo of fedora on monitor 1 when running kernel 3.9.x while I have it on both screens when running kernel 3.8.11
I am able to hit CTRL+f2 to get a text login.
I will attache my dmesg output for both kernels.
Created attachment 102831 [details]
Dmesg using kernel 3.8.11
Created attachment 102841 [details]
Dmesg using kernel 3.9.4 (bad)
I don't that this is related to this bug. Here the monitor stays blank as soon as the nouveau driver is loaded.
For more info:
Solved in https://bugs.freedesktop.org/show_bug.cgi?id=64904