[F][PATCH 0/2] Fixes for memory corruption and a deadlock in i915

[Seth Forshee]

On Tue, Apr 07, 2020 at 03:27:38PM -0700, Sultan Alsawaf wrote:
> In 5.4, i915 suffers from a mutex deadlock that occurs when kswapd runs i915's
> shrinker to free memory. This was fixed in 5.5, but the 5.5 fix is too invasive
> to backport (see the commit message for details).
> 
> Another bug, memory corruption caused by a race in i915, affects 5.4+ and has
> not been fixed by upstream. On 5.4, this crash causes a kernel panic, but on
> 5.5+ the memory corruption from the race doesn't cause an immediate panic.
> 
> The attached fixes for these bugs were submitted to LKML [1][2] and will
> hopefully be addressed soon. In the meantime, let's pick them into Focal to fix
> the crashes by release time.
> 
> Note that the attached "drm/i915: Synchronize active and retire callbacks"
> patch varies from the upstream submission for it because it is the backport of
> the fix to 5.4.
> 
> [1] https://lore.kernel.org/stable/20200407203222.2493-1-sultan@kerneltoast.com
> [2] https://lore.kernel.org/stable/20200407064007.7599-1-sultan@kerneltoast.com

I haven't had time to review these properly, but one comment up front.
These patches are not (yet) upstream, so they need to be marked as
sauce.

Seth