Re: [RFC PATCH 1/5] x86/xen: disable swiotlb for xen pvh

[Jan Beulich]

On 12.03.2023 13:01, Huang Rui wrote:
> Xen PVH is the paravirtualized mode and takes advantage of hardware
> virtualization support when possible. It will using the hardware IOMMU
> support instead of xen-swiotlb, so disable swiotlb if current domain is
> Xen PVH.

But the kernel has no way (yet) to drive the IOMMU, so how can it get
away without resorting to swiotlb in certain cases (like I/O to an
address-restricted device)?

Jan