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| author | Lu Baolu <baolu.lu@linux.intel.com> | 2023-11-22 11:26:03 +0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2023-11-27 11:07:51 +0100 |
| commit | 0f5432a9b839847dcfe9fa369d72e3d646102ddf (patch) | |
| tree | cb0c12860a622c6794190d764a0edd5fe3adc5db | |
| parent | e645c20e8e9cde549bc233435d3c1338e1cd27fe (diff) | |
| download | lwn-0f5432a9b839847dcfe9fa369d72e3d646102ddf.tar.gz lwn-0f5432a9b839847dcfe9fa369d72e3d646102ddf.zip | |
iommu/vt-d: Omit devTLB invalidation requests when TES=0
The latest VT-d spec indicates that when remapping hardware is disabled
(TES=0 in Global Status Register), upstream ATS Invalidation Completion
requests are treated as UR (Unsupported Request).
Consequently, the spec recommends in section 4.3 Handling of Device-TLB
Invalidations that software refrain from submitting any Device-TLB
invalidation requests when address remapping hardware is disabled.
Verify address remapping hardware is enabled prior to submitting Device-
TLB invalidation requests.
Fixes: 792fb43ce2c9 ("iommu/vt-d: Enable Intel IOMMU scalable mode by default")
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20231114011036.70142-2-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/intel/dmar.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/iommu/intel/dmar.c b/drivers/iommu/intel/dmar.c index a3414afe11b0..23cb80d62a9a 100644 --- a/drivers/iommu/intel/dmar.c +++ b/drivers/iommu/intel/dmar.c @@ -1522,6 +1522,15 @@ void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid, { struct qi_desc desc; + /* + * VT-d spec, section 4.3: + * + * Software is recommended to not submit any Device-TLB invalidation + * requests while address remapping hardware is disabled. + */ + if (!(iommu->gcmd & DMA_GCMD_TE)) + return; + if (mask) { addr |= (1ULL << (VTD_PAGE_SHIFT + mask - 1)) - 1; desc.qw1 = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE; @@ -1587,6 +1596,15 @@ void qi_flush_dev_iotlb_pasid(struct intel_iommu *iommu, u16 sid, u16 pfsid, unsigned long mask = 1UL << (VTD_PAGE_SHIFT + size_order - 1); struct qi_desc desc = {.qw1 = 0, .qw2 = 0, .qw3 = 0}; + /* + * VT-d spec, section 4.3: + * + * Software is recommended to not submit any Device-TLB invalidation + * requests while address remapping hardware is disabled. + */ + if (!(iommu->gcmd & DMA_GCMD_TE)) + return; + desc.qw0 = QI_DEV_EIOTLB_PASID(pasid) | QI_DEV_EIOTLB_SID(sid) | QI_DEV_EIOTLB_QDEP(qdep) | QI_DEIOTLB_TYPE | QI_DEV_IOTLB_PFSID(pfsid); |