RE: [RFC PATCH 00/42] Sharing KVM TDP to IOMMU

Tian, Kevin
2023-12-05T06:30:36Z

> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Monday, December 4, 2023 11:08 PM
>
> On Sat, Dec 02, 2023 at 05:12:11PM +0800, Yan Zhao wrote:
> > - How to map MSI page on arm platform demands discussions.
>
> Yes, the recurring problem :(
>
> Probably the same approach as nesting would work for a hack - map the
> ITS page into the fixed reserved slot and tell the guest not to touch
> it and to identity map it.
>

yes logically it should follow what is planned for nesting.

just that kvm needs to involve more iommu specific knowledge e.g.
iommu_get_msi_cookie() to reserve the slot.