diff --git a/drivers/gpu/drm/radeon/radeon_ttm.c b/drivers/gpu/drm/radeon/radeon_ttm.c
index 7e3eb8e80095..7a10b3852970 100644
--- a/drivers/gpu/drm/radeon/radeon_ttm.c
+++ b/drivers/gpu/drm/radeon/radeon_ttm.c
@@ -502,6 +502,8 @@ static int radeon_ttm_io_mem_reserve(struct ttm_bo_device *bdev, struct ttm_mem_
 			mem->bus.addr =
 				ioremap_nocache(mem->bus.base + mem->bus.offset,
 						mem->bus.size);
+		if (!mem->bus.addr)
+			return -ENOMEM;
 
 		/*
 		 * Alpha: Use just the bus offset plus