The scratch page is directly visible in the users address space, and while this is forced as CACHE_LLC, by the kernel, we still have to contend with things like "Bypass-LLC" MOCS. So just flush no matter what. Signed-off-by: Matthew Auld <matthew.auld@xxxxxxxxx> Cc: Thomas Hellström <thomas.hellstrom@xxxxxxxxxxxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Ramalingam C <ramalingam.c@xxxxxxxxx> --- drivers/gpu/drm/i915/gt/intel_gtt.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/gpu/drm/i915/gt/intel_gtt.c b/drivers/gpu/drm/i915/gt/intel_gtt.c index 67d14afa6623..b6c088423319 100644 --- a/drivers/gpu/drm/i915/gt/intel_gtt.c +++ b/drivers/gpu/drm/i915/gt/intel_gtt.c @@ -273,6 +273,7 @@ static void poison_scratch_page(struct drm_i915_gem_object *scratch) val = POISON_FREE; memset(vaddr, val, scratch->base.size); + clflush_cache_range(vaddr, scratch->base.size); } int setup_scratch_page(struct i915_address_space *vm) -- 2.26.3