[Intel-gfx] [PATCH xf86-video-intel] sna: Fix double-free crashes.

[Alexei Podtelezhnikov]

>> Fix double-free crashes.
>> See https://bugzilla.redhat.com/show_bug.cgi?id=1808767
> 
> It should be impossible to get here, so this is just papering over a
> bug.

You sound certain that locking is airtight and pthread.so just happened to be there. The crashes are quite random but seem to need memory shortage. Please also try while I am working on a full debug.