[Intel-gfx] system freeze with kernel 3.2-rc7

[Ben Widawsky]

On Mon, Dec 26, 2011 at 01:43:37AM +0100, Kai Krakow wrote:
> Hello!
> 
> I found my system freeze mostly during starting up X and KDE. Sometimes it 
> works for some minutes, sometimes it freezes immediatly. When the freeze 
> happens, everything is dead (even the reset button does not work, I need to 
> power cycle).
> 
> I was using libdrm-2.4.27 before, system freeze showed some colorful lines 
> running down at the left side of the screen after turning black, then some 
> blue flicker in the top 10% of the the screen. System no longer reacts, 
> network is dead too.
> 
> Now, using libdrm-2.4.29, the system freeze shows other effects: Screen does 
> not turn black but starts to flicker and occassionally moves some 
> centimeters to the right (wrapping the right-most part to the left) for a 
> very short time, then jumping back with some distortions. The rest is the 
> same: Complete freeze, even reset button stops working.
> 
> Before finding out about the libdrm difference, I tried other intel xorg 
> driver versions to no avail, I tried with SNA support and without. No 
> difference. I'm now back to intel xorg driver 2.17.0.
> 
> I read about the semaphores feature, turned it off: No change. Sometimes the 
> system even freezes before displaying the framebuffer splash.
> 
> I didn't have such issues with early 3.2 rcs (afair), and not with 3.1 
> kernels. After some digging through google I've found you enabled RC6 in 
> 3.2. I disabled it now, and my system runs wonderfully.
> 
> Do you need any specs? I'd be happy to send these. The system is a Z68 Pro 
> board with Sandybridge i5-2500K processor, 8 GB of RAM and UEFI firmware. 
> Looks like RC6 is not ready for roll-out, at least on some mainboards.
> 
> Regards,
> Kai

Can you please try this kernel:
git://people.freedesktop.org/~bwidawsk/drm-intel context-support

You probably need to manually enable rc6. We were given some hint that
we may not be setting up contexts properly. The above branch should
create a default context (amongst other stuff which won't happen in this
case).

Thanks.
Ben