drm/i915/buddy: sanity check the size

Ensure we check that the size is compatible with the requested
page_size. For tiny objects that are automatically annotated with
TTM_PL_FLAG_CONTIGUOUS(since they fit within a single page), we
currently end up silently overriding the min_page_size, which ends up
hiding bugs elsewhere.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Nirmoy Das <nirmoy.das@linux.intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220420181613.70033-2-matthew.auld@intel.com

diff --git a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
index 8e4e3f7..a510954 100644 (file)
--- a/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
+++ b/drivers/gpu/drm/i915/i915_ttm_buddy_manager.c
@@ -70,6 +70,7 @@ static int i915_ttm_buddy_man_alloc(struct ttm_resource_manager *man,
                min_page_size = bo->page_alignment << PAGE_SHIFT;
 
        GEM_BUG_ON(min_page_size < mm->chunk_size);
+       GEM_BUG_ON(!IS_ALIGNED(size, min_page_size));
 
        if (place->fpfn + bman_res->base.num_pages != place->lpfn &&
            place->flags & TTM_PL_FLAG_CONTIGUOUS) {