Re: [Intel-gfx] [PATCH] drm/i915: fix i915 running as dom0 under Xen

From: Chris Wilson
Date: Thu Feb 02 2017 - 05:55:58 EST


On Thu, Feb 02, 2017 at 11:48:21AM +0100, Daniel Vetter wrote:
> On Thu, Feb 02, 2017 at 10:47:11AM +0100, Juergen Gross wrote:
> > Commit 920cf4194954ec ("drm/i915: Introduce an internal allocator for
> > disposable private objects") introduced a regression for the kernel
> > running as Xen dom0: when switching to graphics mode a GPU HANG
> > occurred.
> >
> > Reason seems to be a missing adaption similar to that done in
> > commit 7453c549f5f648 ("swiotlb: Export swiotlb_max_segment to users")
> > to i915_gem_object_get_pages_internal().
> >
> > So limit the maximum page order to be used according to the maximum
> > swiotlb segment size instead to the complete swiotlb size.
> >
> > Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
> Fixes: 920cf4194954 ("drm/i915: Introduce an internal allocator for disposable private objects")
> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxxxxxxxx>
> Cc: Daniel Vetter <daniel.vetter@xxxxxxxxx>
> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>
> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx
> Cc: <drm-intel-fixes@xxxxxxxxxxxxxxxxxxxxx> # v4.10-rc1+
>
> We have a nice script for these :-)

Pffifle. 7453c549f5f648 allowed Xen to change it and silently conflicted
with those that already used the previous limits, which didn't land in
our tree until v4.10-rc3.
-Chris

--
Chris Wilson, Intel Open Source Technology Centre