Re: [PATCH v3 1/5] iommu: Return -EMEDIUMTYPE for incompatible domain and device/group

From: Baolu Lu
Date: Thu Jun 23 2022 - 21:36:03 EST


On 2022/6/24 04:00, Nicolin Chen wrote:
diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c
index e1cb51b9866c..5386d889429d 100644
--- a/drivers/iommu/mtk_iommu_v1.c
+++ b/drivers/iommu/mtk_iommu_v1.c
@@ -304,7 +304,7 @@ static int mtk_iommu_v1_attach_device(struct iommu_domain *domain, struct device
/* Only allow the domain created internally. */
mtk_mapping = data->mapping;
if (mtk_mapping->domain != domain)
- return 0;
+ return -EMEDIUMTYPE;
if (!data->m4u_dom) {
data->m4u_dom = dom;

This change looks odd. It turns the return value from success to
failure. Is it a bug? If so, it should go through a separated fix patch.

Best regards,
baolu