[XEN PATCH v4 0/5] x86/iommu: Drop IOMMU support when cx16 isn't supported

[Teddy Astie <teddy.astie@xxxxxxxxxx>]

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. Also disable
interrupt remapping that also relies on cx16.

Teddy Astie (5):
  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
  VT-d: Disable intrerrupt remapping if cx16 is not supported
  AMD-Vi: Disable intrerrupt remapping if cx16 is not supported

 xen/drivers/passthrough/amd/iommu_intr.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      | 70 +++++-----------
 xen/drivers/passthrough/vtd/iommu.c         | 92 +++++++--------------
 xen/drivers/passthrough/vtd/vtd.h           |  5 +-
 6 files changed, 77 insertions(+), 144 deletions(-)

-- 
2.44.0



Teddy Astie | Vates XCP-ng Intern

XCP-ng & Xen Orchestra - Vates solutions

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