diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 6f7f4114afcf..3db8e499d4c5 100644
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -67,7 +67,6 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname,
 		return ret;
 
 	mem_phys = r.start;
-	mem_size = resource_size(&r);
 
 	/* Request the MDT file for the firmware */
 	fw = adreno_request_fw(to_adreno_gpu(gpu), fwname);
@@ -83,6 +82,13 @@ static int zap_shader_load_mdt(struct msm_gpu *gpu, const char *fwname,
 		goto out;
 	}
 
+	if (mem_size > resource_size(&r)) {
+		DRM_DEV_ERROR(dev,
+			"memory region is too small to load the MDT\n");
+		ret = -E2BIG;
+		goto out;
+	}
+
 	/* Allocate memory for the firmware image */
 	mem_region = memremap(mem_phys, mem_size,  MEMREMAP_WC);
 	if (!mem_region) {