Commit a4fdd9762272 ("iommu: Use flush queue capability") hid the IOMMU_DOMAIN_DMA_FQ domain type from domain allocation. A check was introduced in iommu_dma_init_domain() to fall back if not supported, but this check runs too late: by that point, devices have been attached to the IOMMU, and apple-dart's attach_dev() callback does not expect IOMMU_DOMAIN_DMA_FQ domains. Change the logic so the IOMMU_DOMAIN_DMA codepath is the default, instead of explicitly enumerating all types. Fixes an apple-dart regression in v6.5. Cc: regressions@xxxxxxxxxxxxxxx Cc: stable@xxxxxxxxxxxxxxx Suggested-by: Robin Murphy <robin.murphy@xxxxxxx> Fixes: a4fdd9762272 ("iommu: Use flush queue capability") Signed-off-by: Hector Martin <marcan@xxxxxxxxx> --- Changes in v2: - Fixed the issue in apple-dart instead of the iommu core, per Robin's suggestion. - Link to v1: https://lore.kernel.org/r/20230922-iommu-type-regression-v1-1-1ed3825b2c38@xxxxxxxxx --- drivers/iommu/apple-dart.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c index 2082081402d3..0b8927508427 100644 --- a/drivers/iommu/apple-dart.c +++ b/drivers/iommu/apple-dart.c @@ -671,8 +671,7 @@ static int apple_dart_attach_dev(struct iommu_domain *domain, return ret; switch (domain->type) { - case IOMMU_DOMAIN_DMA: - case IOMMU_DOMAIN_UNMANAGED: + default: ret = apple_dart_domain_add_streams(dart_domain, cfg); if (ret) return ret; --- base-commit: ce9ecca0238b140b88f43859b211c9fdfd8e5b70 change-id: 20230922-iommu-type-regression-25b4f43df770 Best regards, -- Hector Martin <marcan@xxxxxxxxx>