Black screen/blinking cursor

[mdimura]

I ran commands as suggested in Quick start on linux mint Rebecca KDE (ubuntu 14.04). As a result I have black screen with white cursor blinking. Logs attached. syslog: http://pastebin.com/H7WLMw5k Xorg.0.log: http://pastebin.com/pdHVnU4y Xorg.failsafe.log: http://pastebin.com/VFmMQ4zc

[ustuehler]

This line in Xorg.0.log means that the nouveau driver was unable to initialize DRM. The X server then uses fbdev as a fallback driver:

[173979.952] (EE) [drm] failed to open device

I have never tested this with an nvidia card, but I found this trouble shooting guide for the nouveau driver. Can you go through that?

Here's an example of the loaded modules with an intel card:

$ lsmod | grep drm
drm_kms_helper         55071  1 i915
drm                   303102  7 i915,drm_kms_helper

[mdimura]

I am using Nvidia proprietary drivers. Tried adding as suggested at http://unix.stackexchange.com/questions/18003/linux-lxc-deploying-images-with-tiniest-possible-x11

mknod -m 666 /dev/nvidia0 c 195 0
mknod -m 666 /dev/nvidiactl c 195 255

But it did not help - still get (EE) [drm] failed to open device message. drm seem to be loaded in container:

# lsmod | grep drm
drm                   302817  2 nvidia

[ustuehler]

Since /dev is a tmpfs, these device nodes don't persist across restarts of the container. Please pull and rebuild/reinstall the lxc-desktop package. I've updated the hook script to clone those devices if they exist on the host, each time the container starts.

[mdimura]

Sure, I should have mentioned, I put the mknod commands in the init script, did not help, however. I also tried removing the container, updating the lxc-desktop and creating the container anew - the same result: black screen, blinking _ cursor. If I attach to the container - devices are populated as expected.

# ls /dev/nv*
/dev/nvidia0  /dev/nvidiactl
# lsmod | grep drm
drm                   302817  2 nvidia

[ustuehler]

Try adding something like the following to /etc/lightdm/lightdm.conf inside the container and then post the resulting trace file:

[SeatDefaults]
xserver-command=strace -o /var/tmp/X.trace -f X

I would like to know what the nouveau driver is trying to do to initialize DRM. Maybe there's an additional device node missing.

[ustuehler]

I am using Nvidia proprietary drivers.

From the original Xorg.0.log that you attached, it doesn't look like you do:

[173979.325] (WW) Warning, couldn't open module nvidia

Perhaps the nvidia package isn't installed in the LXC container?

[mdimura]

Yes, this may be the reason. I did not realise in the beginning, that "ubuntu-desktop" is a 12.04 container. Installing proper nvidia drivers in the 12.04 container seems difficult.

[ustuehler]

Perhaps it is possible to just copy the driver module from /usr/lib/xorg/modules/drivers on your host?

[mdimura]

Tried copying the module from the host, driver seems to load, but the problem persists. Xorg.0.log