[Intel-gfx] [PATCH v3 0/2] Don't use stolen memory or BAR mappings for ring buffers

[John.C.Harrison@Intel.com]

From: John Harrison <John.C.Harrison@Intel.com>

Instruction from hardware arch is that stolen memory and BAR mappings
are unsafe for use as ring buffers. There can be issues with cache
aliasing due to the CPU access going to memory via the BAR. So, don't
do it.

v2: Dont use BAR mappings either.
Make conditional on LLC so as not to change platforms that don't need
to change (Daniele).
Add 'Fixes' tags (Tvrtko).
v3: Fix dumb typo.

Signed-off-by: John Harrison <John.C.Harrison@Intel.com>


John Harrison (2):
  drm/i915: Don't use stolen memory for ring buffers with LLC
  drm/i915: Don't use BAR mappings for ring buffers with LLC

 drivers/gpu/drm/i915/gt/intel_ring.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

-- 
2.39.1