From 7024f80efcce8122fe8db3e0b4c096eb199333eb Mon Sep 17 00:00:00 2001 From: Matthew Auld Date: Tue, 4 Oct 2022 14:19:16 +0100 Subject: [PATCH] drm/i915: check memory is mappable in read_from_page MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On small-bar systems we could be given something non-mappable here, which leads to nasty oops. Make this nicer by checking if the resource is mappable or not, and return an error otherwise. v2: drop GEM_BUG_ON(flags & I915_BO_ALLOC_GPU_ONLY) Signed-off-by: Matthew Auld Cc: Jianshui Yu Cc: Ville Syrjälä Cc: Nirmoy Das Reviewed-by: Nirmoy Das Link: https://patchwork.freedesktop.org/patch/msgid/20221004131916.233474-5-matthew.auld@intel.com --- drivers/gpu/drm/i915/gem/i915_gem_object.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c index 369006c5317f..62495d5d0038 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_object.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c @@ -444,6 +444,16 @@ i915_gem_object_read_from_page_iomap(struct drm_i915_gem_object *obj, u64 offset io_mapping_unmap(src_map); } +static bool object_has_mappable_iomem(struct drm_i915_gem_object *obj) +{ + GEM_BUG_ON(!i915_gem_object_has_iomem(obj)); + + if (IS_DGFX(to_i915(obj->base.dev))) + return i915_ttm_resource_mappable(i915_gem_to_ttm(obj)->resource); + + return true; +} + /** * i915_gem_object_read_from_page - read data from the page of a GEM object * @obj: GEM object to read from @@ -466,7 +476,7 @@ int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, if (i915_gem_object_has_struct_page(obj)) i915_gem_object_read_from_page_kmap(obj, offset, dst, size); - else if (i915_gem_object_has_iomem(obj)) + else if (i915_gem_object_has_iomem(obj) && object_has_mappable_iomem(obj)) i915_gem_object_read_from_page_iomap(obj, offset, dst, size); else return -ENODEV;