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

[Kai Krakow]

Keith Packard <keithp at keithp.com> schrieb:

> You almost certainly don't need IOMMU/VT-d support though; that
> virtualizes devices for DMA by the guest OS, which generally no-one
> does.
> 
> The BIOS manual for the Z68 board mentions two configuration options,
> 
> CPU Configuration:
>     Intel Virtualization Technology

This exists...

> North Bridge Configuration:
>     VT-d

This doesn't...

> I'd love to see tests with these in the three possible combinations:
> 
>         VT enabled, VT-d enabled
>         VT enabled, VT-d disabled
>         VT disabled, VT-d disabled

Since there's only VT in my BIOS, I tested both settings, and both failed. I 
can only reliably boot with RC6 disabled. Otherwise it reproducably hangs on 
a black screen either just before the boot splash or it never shows the boot 
splash from initramfs (but works, I see HD activity) and then hangs on 
loading the next boot splash from real_root. The monitor goes into idle when 
this happens. But usually the system gets past this and later fails to start 
or log in to X. The screen goes crazy (flickering or colorful stripes 
running down the left side of the screen) when this happens. System freezes 
completely, e.g. if I had HD activity the LED stays on forever, hw reset 
button dead.

> Meanwhile, I'll get a patch ready for 3.2 which disables RC6 again.

If I should provide more info to identify my system, please tell me.

Regards,
Kai