[Call for testers] DRM device-independent code update to Linux 3.8 (take #2)

[Jakob Alvermark]

On 26 mar 2015, at 22:00, Jakob Alvermark wrote:

> On Tue, March 24, 2015 00:29, Hans Petter Selasky wrote:
>> Hi,
>> 
>> 
>> Without the attached kernel patch(es), Xorg starts consuming alot of CPU
>> and becomes very unresponsive and unusable.
>> 
>> Using ktrace reveals that X-org is issuing DRM_IOCTL_MODE_GETCONNECTOR
>> over and over again with no apparent reason. It doesn't happen when using a
>> simple window manager like blackbox. I was not able to use XFCE4 (9-stable
>> userland) with 11-current kernel at all, after the latest DRM2 kernel
>> updates. It worked fine before the update.
>> 
>> I'm not sure what is causing it. Going through the new DRM2 code
>> revealed that a mode sorting function did not take all parameters like
>> interlaced or not into account, causing the mode list to be reshuffelled
>> every time a new mode scan was done. Not sure if Xorg cares about this
>> though.
> 
> I got the same problem with XFCE4, Xorg at 100% CPU.
> 
> Applied the patch and it works again.

Interestingly, xrandr now lists a lot more available modes than before the DRM code update.
I thought it was my cheap TV that only supported 1080i, but it turns out that now I can use 1080p at 60Hz!

Jakob