Bug#500281: xserver-xorg-video-savage: freezes the entire system with some OpenGL screensavers

[Brice Goglin <Brice.Goglin@ens-lyon.org>]

Francesco Poli wrote:
> Nonetheless, the test was not completely error free.  Indeed, some
> worrying entries were logged to /var/log/kern.log:
>
>
> [  582.975686] Xorg:5396 conflicting memory types 90000000-95000000 uncached-minus<->write-combining
> [  582.975700] reserve_memtype failed 0x90000000-0x95000000, track uncached-minus, req uncached-minus
> [  643.989097] atunnel:5735 conflicting memory types 90000000-95000000 uncached-minus<->write-combining
> [  643.989123] reserve_memtype failed 0x90000000-0x95000000, track uncached-minus, req uncached-minus
> [  653.768420] atunnel:5737 conflicting memory types 90000000-95000000 uncached-minus<->write-combining
> [  653.768446] reserve_memtype failed 0x90000000-0x95000000, track uncached-minus, req uncached-minus
> [  686.813969] atunnel:5756 conflicting memory types 90000000-95000000 uncached-minus<->write-combining
> [  686.813997] reserve_memtype failed 0x90000000-0x95000000, track uncached-minus, req uncached-minus
>
>
> As a consequence, I am *not* sure that the bug can be safely considered
> as fixed...
>   

This looks like a kernel problem to me. It's probably the Xserver asking
the kernel to set some memory range as WC but the kernel PAT code fails
to do so for some reason, it sets UC- minus instead (things should be
slower then). Which kernel are you using ?

Brice