GPU hang on ThinkPad T420 with drm-kmod on 12.0-RELEASE

[Kevin Zheng]

On 1/3/19 11:44 PM, Kevin Oberman wrote:
> I am running on 12.0-STABLE r342382 on my T500 with Sandy Bridge. Other 
> than screen size, I believe that it is identical with the T420. Are you 
> sure that yours is ivy Bridge? Maybe later T420schanged processors?

No, you're right; T420 is Sandy Bridge (CPUID=0x206a7). Not that this 
makes much of a difference here.

> I just discovered that it is essential that I run with the modesetting 
> driver, not xf86-video-intel. Are you running modesetting? Using he 
> older driver triggered several issues for me.I also am running mesa 
> 18.3.1 which is currently under test (and will hopefully be in ports 
> soon). You can find the patches to 18.2.8 and then to 18.2.8  is covered 
> inbug 230298 <https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=230298> 
> and 18.3.1 in bug 233034 
> <https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=233034>. Patches must 
> be applied in sequence and with the -E option.

Yes, I'm running the KMS driver, not the old driver.

> I have now been running on the system for over a day with no issues, but 
> I need to give it more time before I pronounce it satisfactory. I also 
> use Firefox, but I will give chromium a shot now and see if there is a 
> problem.

So have I; normal use doesn't shake the GPU hang out. I see the crash 
occasionally when running Chromium and reasonably frequently when I run 
games/supertuxkart. Unfortunately I don't have any more info right now. 
I can try the updated Mesa.

-- 
Kevin Zheng
kevinz5000 at gmail.com | kevinz at berkeley.edu | PGP: 0xC22E1090