From: Chris Wilson chris@chris-wilson.co.uk
commit ba2ebf605d5f32a9be0f7b05d3174bbc501b83fe upstream.
Let's not try and use PAT attributes for I915_MAP_WC if the CPU doesn't support PAT.
Fixes: 6056e50033d9 ("drm/i915/gem: Support discontiguous lmem object maps") Signed-off-by: Chris Wilson chris@chris-wilson.co.uk Reviewed-by: Matthew Auld matthew.auld@intel.com Cc: stable@vger.kernel.org # v5.6+ Link: https://patchwork.freedesktop.org/patch/msgid/20200915091417.4086-2-chris@ch... (cherry picked from commit 121ba69ffddc60df11da56f6d5b29bdb45c8eb80) Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/gpu/drm/i915/gem/i915_gem_pages.c | 4 ++++ 1 file changed, 4 insertions(+)
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c @@ -254,6 +254,10 @@ static void *i915_gem_object_map(struct if (!i915_gem_object_has_struct_page(obj) && type != I915_MAP_WC) return NULL;
+ if (GEM_WARN_ON(type == I915_MAP_WC && + !static_cpu_has(X86_FEATURE_PAT))) + return NULL; + /* A single page can always be kmapped */ if (n_pte == 1 && type == I915_MAP_WB) { struct page *page = sg_page(sgt->sgl);