https://bugzilla.kernel.org/show_bug.cgi?id=87791
--- Comment #4 from Michel Dänzer michel@daenzer.net --- (In reply to aCaB from comment #3)
I understand mesa may be sending crap to the kernel space but that doesn't sound like a good reason to deref a NULL.
AFAICT that should be fixed by the changes to radeon_ttm.c in https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=5... .