Re: 3.5 regression on i915

[Chris Wilson]

On Sat, 6 Oct 2012 09:59:56 +0200, Willy Tarreau <w@xxxxxx> wrote:
> On Sat, Oct 06, 2012 at 03:43:56AM -0400, Dave Airlie wrote:
> > On Sat, Oct 6, 2012 at 3:27 AM, Willy Tarreau <w@xxxxxx> wrote:
> > > On Sat, Oct 06, 2012 at 01:58:45AM +0200, Willy Tarreau wrote:
> > >> On Sat, Oct 06, 2012 at 09:48:57AM +1000, Dave Airlie wrote:
> > >> > Any reason you don't have KMS, you'll keep hitting these non-kms bugs
> > >> > since it has no users anymore really.
> > >> >
> > >> > Granted they'll get fixed, but I suspect its a losing battle over time.
> > >>
> > >> Well, back in old times every time I tried to enable it, I only ran into
> > >> problems so I got used to disable it, which made sense since it didn't
> > >> bring me any benefit.
> > >
> > > OK I found why in the end. When I enable KMS, my X server fails to start
> > > and segfaults in intel_drv.so. So I think that the comment in Kconfig
> > > below is quite appropriate :
> > 
> > Okay are you running a really old userspace? just wondering what could
> > cause this.
> 
> yes, my Xorg is 1.4.2 and xf86-video-intel is 2.7.1.
> 
> I have additional information, I retested with 3.4.12 with and without KMS :
> 
>    3.4.12, no KMS : X works fine
>    3.4.12, KMS    : X works fine but some garbage follows the mouse pointer
>                     on the external display
>    3.5.x   no KMS : kernel BUG
>    3.5.x   KMS    : X server segfaults in intel driver
> 
> So in fact, both the KMS/non-KMS confs have regressed in 3.5 on this setup.
> 
> It is possible that the commit which removed the list of pinned inactive
> objects (1b50247a) has uncovered another long-time bug.

More likely X is segfaulting for another reason altogether. Can you
please attach the stacktrace (with symbols!) and see if another
bisection is required?
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre
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