All hardware that supports VT-d/AMD-Vi that exists also supports cx16 (aside specifically crafted virtual machines).
Some IOMMU code paths in Xen consider cases where VT-d/AMD-Vi is supported while cx16 isn't, those paths may be bugged and are barely tested, dead code in practice. Disable IOMMU in case we have IOMMU hardware but no cx16, then cleanup no-cx16 handling logic from VT-d and AMD-Vi drivers. Teddy Changed in v2: * Added cleanup no-cx16 code for x2APIC * Fixed commit and code formatting * Added missing Suggested-by note Changed in v3: * Use -ENODEV instead of -ENOSYS. Teddy Astie (3): VT-d: Disable IOMMU if cx16 isn't supported AMD-Vi: Disable IOMMU if cx16 isn't supported VT-d: Cleanup MAP_SINGLE_DEVICE and related code xen/arch/x86/apic.c | 6 ++ xen/drivers/passthrough/amd/iommu_map.c | 42 ++++------ xen/drivers/passthrough/amd/pci_amd_iommu.c | 6 ++ xen/drivers/passthrough/vtd/intremap.c | 65 ++++----------- xen/drivers/passthrough/vtd/iommu.c | 92 +++++++-------------- xen/drivers/passthrough/vtd/vtd.h | 5 +- 6 files changed, 71 insertions(+), 145 deletions(-) -- 2.44.0 Teddy Astie | Vates XCP-ng Intern XCP-ng & Xen Orchestra - Vates solutions web: https://vates.tech
