The "ret" variable is declared as ssize_t and it can hold negative error codes but the "rk_obj->base.size" variable is type size_t. This means that when we compare them, they are both type promoted to size_t and the negative error code becomes a high unsigned value and is treated as success. Add a cast to fix this. Fixes: 38f993b7c59e ("drm/rockchip: Do not use DMA mapping API if attached to IOMMU domain") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- drivers/gpu/drm/rockchip/rockchip_drm_gem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c index b8f8b45ebf59..93ed841f5dce 100644 --- a/drivers/gpu/drm/rockchip/rockchip_drm_gem.c +++ b/drivers/gpu/drm/rockchip/rockchip_drm_gem.c @@ -40,7 +40,7 @@ static int rockchip_gem_iommu_map(struct rockchip_gem_object *rk_obj) ret = iommu_map_sgtable(private->domain, rk_obj->dma_addr, rk_obj->sgt, prot); - if (ret < rk_obj->base.size) { + if (ret < (ssize_t)rk_obj->base.size) { DRM_ERROR("failed to map buffer: size=%zd request_size=%zd\n", ret, rk_obj->base.size); ret = -ENOMEM; -- 2.39.2