On Sun, Dec 14, 2014 at 12:58:31PM +0100, Heinz Diehl wrote:

Hi,

since kernel 3.18 I'm no longer able to run X on my machine. While 3.17.6 is fine, 3.18 leaves me with a black screen when starting X. Booting into runlevel 1/3 is fine.

I did a "git bisect", and the offending commit is this one:

[root@kiera linux-git]# git bisect bad 83f45fc360c8e16a330474860ebda872d1384c8c is the first bad commit commit 83f45fc360c8e16a330474860ebda872d1384c8c Author: Daniel Vetter daniel.vetter@ffwll.ch Date: Wed Aug 6 09:10:18 2014 +0200

drm: Don't grab an fb reference for the idr

[....]

I double-checked, and 3.18 is fine with this commit reverted.

My machine is an Asus U45JC laptop, and the CPU is an Intel i450M (Ironlake). Please contact me if I can help in any way (I'm subscribed to lkml, but not to other X or kernel related lists).

Can you please boot with drm.debug=0xf on both good and bad kernels and then grab dmesg from each?

To make sure we don't forget this please file the above summary plus dmesg files as a new bug against dri -> drm(intel) on bugs.freedesktop.org. Please add "[ilk bisected]" to the bug summary so it shows up in all the right searches for us.

Thanks, Daniel