This is a note to let you know that I've just added the patch titled
iommu/vt-d: Disable PCI ATS in legacy passthrough mode
to the 6.6-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
iommu-vt-d-disable-pci-ats-in-legacy-passthrough-mod.patch
and it can be found in the queue-6.6 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6bfd72bd25cdd0cdf20f7fcc8876b8b238ba844a
Author: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Date: Wed Nov 22 11:26:04 2023 +0800
iommu/vt-d: Disable PCI ATS in legacy passthrough mode
[ Upstream commit da37dddcf4caf015c400a930301d2ee27a7a15fb ]
When IOMMU hardware operates in legacy mode, the TT field of the context
entry determines the translation type, with three supported types (Section
9.3 Context Entry):
- DMA translation without device TLB support
- DMA translation with device TLB support
- Passthrough mode with translated and translation requests blocked
Device TLB support is absent when hardware is configured in passthrough
mode.
Disable the PCI ATS feature when IOMMU is configured for passthrough
translation type in legacy (non-scalable) mode.
Fixes: 0faa19a1515f ("iommu/vt-d: Decouple PASID & PRI enabling from SVA")
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Link: https://lore.kernel.org/r/20231114011036.70142-3-baolu.lu@xxxxxxxxxxxxxxx
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 8e878c3beec5c..18fa71aadc903 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2487,7 +2487,8 @@ static int dmar_domain_attach_device(struct dmar_domain *domain,
return ret;
}
- iommu_enable_pci_caps(info);
+ if (sm_supported(info->iommu) || !domain_type_is_si(info->domain))
+ iommu_enable_pci_caps(info);
return 0;
}
