lib/intel_memory_region: verify item.length

If the regions query fails then the error will be encoded in the
item.length, while the ioctl will still return success.

Reported-by: Ville Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/i915/intel_memory_region.c b/lib/i915/intel_memory_region.c
index 144ae12c..e1e210f2 100644
--- a/lib/i915/intel_memory_region.c
+++ b/lib/i915/intel_memory_region.c
@@ -119,6 +119,13 @@ struct drm_i915_query_memory_regions *gem_get_query_memory_regions(int fd)
 	memset(&item, 0, sizeof(item));
 	item.query_id = DRM_I915_QUERY_MEMORY_REGIONS;
 	i915_query_items(fd, &item, 1);
+	/*
+	 * Any DRM_I915_QUERY_MEMORY_REGIONS specific errors are encoded in the
+	 * item.length, even though the ioctl might still return success.
+	 */
+	igt_assert_f(item.length > 0,
+		     "DRM_I915_QUERY_MEMORY_REGIONS failed with %d\n",
+		     item.length);
 
 	query_info = calloc(1, item.length);