From 45e00e36718902d81bdaebb37b3a8244e685bc48 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V (Arm)" Date: Tue, 8 Apr 2025 09:03:51 +0530 Subject: [PATCH] iommu/arm-smmu-v3: Add missing S2FWB feature detection Commit 67e4fe398513 ("iommu/arm-smmu-v3: Use S2FWB for NESTED domains") introduced S2FWB usage but omitted the corresponding feature detection. As a result, vIOMMU allocation fails on FVP in arm_vsmmu_alloc(), due to the following check: if (!arm_smmu_master_canwbs(master) && !(smmu->features & ARM_SMMU_FEAT_S2FWB)) return ERR_PTR(-EOPNOTSUPP); This patch adds the missing detection logic to prevent allocation failure when S2FWB is supported. Fixes: 67e4fe398513 ("iommu/arm-smmu-v3: Use S2FWB for NESTED domains") Signed-off-by: Aneesh Kumar K.V (Arm) Reviewed-by: Jason Gunthorpe Reviewed-by: Nicolin Chen Reviewed-by: Pranjal Shrivastava Link: https://lore.kernel.org/r/20250408033351.1012411-1-aneesh.kumar@kernel.org Signed-off-by: Will Deacon --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index b4c21aaed126..5467f85dd463 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -4429,6 +4429,8 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) reg = readl_relaxed(smmu->base + ARM_SMMU_IDR3); if (FIELD_GET(IDR3_RIL, reg)) smmu->features |= ARM_SMMU_FEAT_RANGE_INV; + if (FIELD_GET(IDR3_FWB, reg)) + smmu->features |= ARM_SMMU_FEAT_S2FWB; /* IDR5 */ reg = readl_relaxed(smmu->base + ARM_SMMU_IDR5); -- 2.50.1