Re: vanilla kernels hang randomly under Fedora 10 on system with Radeon card

[Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>]

On Tuesday 02 December 2008, Dave Airlie wrote:
> On Tue, Dec 2, 2008 at 8:42 AM, Bartlomiej Zolnierkiewicz
> <bzolnier@gmail.com> wrote:
> >
> > Hi,
> >
> > After Fedora 9 -> Fedora 10 upgrade vanilla kernels which previously
> > worked fine (next-20081128 and next-20081121) started to hang randomly
> > on my Pentium M / 855PM / RV350 laptop.  Since (surprisingly) stock
> > Fedora kernel (2.6.27.5-117.fc10.i686) was not affected I got the idea
> > that either userspace changes uncovered some kernel regression or some
> > Fedora specific patch must be fixing the issue.  Unfortunately vanilla
> > 2.6.27 also freezed so after the usual pain caused by hitting bunch of
> > unrelated problems [1] it turned out that drm-modesetting-radeon.patch
> > is the magic patch and CONFIG_DRM_RADEON_KMS is the magic change.  With
> > the patch and enabling the option next-20081128 works stable again...
> >
> > Since the following error gets logged by kernel:
> >
> > [drm:drm_buffer_object_validate] *ERROR* Failed moving buffer. cef578c0 1444 4000027 10000a0
> > [drm:drm_buffer_object_validate] *ERROR* Out of aperture space or DRM memory quota.
> >
> > and it also seems that system is more responsive now (it was kind of
> > sluggish previously) my draft theory is that F9 -> F10 triggered some
> > AGP memory management bug and CONFIG_DRM_RADEON_KMS happens to fix it
> > but I'll leave figuring this up to the more knowledgeable people... ;)
> 
> Well KMS is a purely Fedora thing, and enabling it completely avoids
> the old driver codepaths so
> while it might fix it, its more by accident than design.
> 
> I'm trying to track down the rv3xx hangs with hpa at the moment as he
> sees them also, something in
>  the 2.6.26->2.6.27 timeframe. I'm hoping running the 2.6.26 drm on
> the 2.6.27 will help narrow it down.
> 
> Bisecting 2.6.26->2.6.27 might also help.

It could be a different issue.  I tried 2.6.26, 2.6.25 and 2.6.24
and they all hang (they all worked fine with Fedora 9)...

I will try some older kernels but I start thinking that the xorg's ati
driver update is the main cause (xorg-x11-drv-ati-6.8.0-19.fc9.i386.rpm
-> xorg-x11-drv-ati-6.9.0-54.fc10.i386.rpm).

Thanks,
Bart