From fb292bfc9be936dade7eef7ec5762de1201983d8 Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Tue, 14 Jul 2026 13:55:05 -0700 Subject: [PATCH] iommu/tegra241-cmdqv: Require exactly one Stream ID for a vSID tegra241_vintf_init_vsid() maps a guest vSID to a single physical Stream ID taken from master->streams[0], and only warns when the device does not have exactly one stream. A device with several streams gets only its first one mapped, so a guest vSID invalidation cannot reach the others' ATC and IOTLB entries; a device with none makes master->streams a ZERO_SIZE_PTR, read out of bounds. Reject the mapping with -EOPNOTSUPP if master->num_streams is not one. Fixes: 4dc0d12474f9 ("iommu/tegra241-cmdqv: Add user-space use support") Assisted-by: Claude:claude-opus-4-8 Signed-off-by: Nicolin Chen Signed-off-by: Will Deacon --- drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c index ad69641dce0f..269a06fcca27 100644 --- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c +++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c @@ -1260,7 +1260,8 @@ static int tegra241_vintf_init_vsid(struct iommufd_vdevice *vdev) if (virt_sid > FIELD_MAX(VINTF_SID_MATCH_VIRT_SID)) return -EINVAL; - WARN_ON_ONCE(master->num_streams != 1); + if (master->num_streams != 1) + return -EOPNOTSUPP; /* Find an empty pair of SID_REPLACE and SID_MATCH */ sidx = ida_alloc_max(&vintf->sids, vintf->cmdqv->num_sids_per_vintf - 1,