diff options
| author | Mostafa Saleh <smostafa@google.com> | 2026-01-02 23:53:52 +0300 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2026-01-08 00:22:33 +0300 |
| commit | 5ac66ed8417fa43f64edbabc5fbac18d2bca9437 (patch) | |
| tree | cf7195c93dc5f2b060c50bc358326e546fcf271a | |
| parent | 2026159372bb6ff5e18e63272473eb4549b0779e (diff) | |
| download | linux-5ac66ed8417fa43f64edbabc5fbac18d2bca9437.tar.xz | |
iommu/arm-smmu-v3: Remove IAS
The driver only supports AArch64 page tables where OAS == IAS.
Remove the extra IAS tracking for AArch32 as this feature was
never implemented and that was creating BAD_STEs for SMMUv3
with stage-2 and OAS < 40.
Further discussion on this in:
https://lore.kernel.org/linux-iommu/20251130194506.593700-1-smostafa@google.com/
Reported-by: Tomasz Nowicki <tnowicki@google.com>
Fixes: f0c453dbcce7 ("iommu/arm-smmu: Ensure IAS is set correctly for AArch32-capable SMMUs")
Signed-off-by: Mostafa Saleh <smostafa@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 18 | ||||
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 2 |
2 files changed, 5 insertions, 15 deletions
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 7a6aea3b61c1..62bdc4d39101 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2562,7 +2562,7 @@ static int arm_smmu_domain_finalise(struct arm_smmu_domain *smmu_domain, ARM_SMMU_FEAT_VAX) ? 52 : 48; pgtbl_cfg.ias = min_t(unsigned long, ias, VA_BITS); - pgtbl_cfg.oas = smmu->ias; + pgtbl_cfg.oas = smmu->oas; if (enable_dirty) pgtbl_cfg.quirks |= IO_PGTABLE_QUIRK_ARM_HD; fmt = ARM_64_LPAE_S1; @@ -2572,7 +2572,7 @@ static int arm_smmu_domain_finalise(struct arm_smmu_domain *smmu_domain, case ARM_SMMU_DOMAIN_S2: if (enable_dirty) return -EOPNOTSUPP; - pgtbl_cfg.ias = smmu->ias; + pgtbl_cfg.ias = smmu->oas; pgtbl_cfg.oas = smmu->oas; fmt = ARM_64_LPAE_S2; finalise_stage_fn = arm_smmu_domain_finalise_s2; @@ -4406,13 +4406,7 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) } /* We only support the AArch64 table format at present */ - switch (FIELD_GET(IDR0_TTF, reg)) { - case IDR0_TTF_AARCH32_64: - smmu->ias = 40; - fallthrough; - case IDR0_TTF_AARCH64: - break; - default: + if (!(FIELD_GET(IDR0_TTF, reg) & IDR0_TTF_AARCH64)) { dev_err(smmu->dev, "AArch64 table format not supported!\n"); return -ENXIO; } @@ -4525,8 +4519,6 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) dev_warn(smmu->dev, "failed to set DMA mask for table walker\n"); - smmu->ias = max(smmu->ias, smmu->oas); - if ((smmu->features & ARM_SMMU_FEAT_TRANS_S1) && (smmu->features & ARM_SMMU_FEAT_TRANS_S2)) smmu->features |= ARM_SMMU_FEAT_NESTING; @@ -4536,8 +4528,8 @@ static int arm_smmu_device_hw_probe(struct arm_smmu_device *smmu) if (arm_smmu_sva_supported(smmu)) smmu->features |= ARM_SMMU_FEAT_SVA; - dev_info(smmu->dev, "ias %lu-bit, oas %lu-bit (features 0x%08x)\n", - smmu->ias, smmu->oas, smmu->features); + dev_info(smmu->dev, "oas %lu-bit (features 0x%08x)\n", + smmu->oas, smmu->features); return 0; } diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index ae23aacc3840..0a5bb57dbdfe 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -43,7 +43,6 @@ struct arm_vsmmu; #define IDR0_COHACC (1 << 4) #define IDR0_TTF GENMASK(3, 2) #define IDR0_TTF_AARCH64 2 -#define IDR0_TTF_AARCH32_64 3 #define IDR0_S1P (1 << 1) #define IDR0_S2P (1 << 0) @@ -784,7 +783,6 @@ struct arm_smmu_device { int gerr_irq; int combined_irq; - unsigned long ias; /* IPA */ unsigned long oas; /* PA */ unsigned long pgsize_bitmap; |