Re: [PATCH 2/4] x86: always initialize xen-swiotlb when xen-pcifront is enabling

[Christoph Hellwig <hch@xxxxxx>]

On Mon, May 22, 2023 at 10:37:09AM +0200, Juergen Gross wrote:
> In normal cases PCI passthrough in PV guests requires to start the guest
> with e820_host=1. So it should be rather easy to limit allocating the
> 64MB in PV guests to the cases where the memory map has non-RAM regions
> especially in the first 1MB of the memory.
>
> This will cover even hotplug cases. The only case not covered would be a
> guest started with e820_host=1 even if no PCI passthrough was planned.
> But this should be rather rare (at least I hope so).

So is this an ACK for the patch and can we go ahead with it?

(I'd still like to merge swiotlb-xen into swiotlb eventually, but it's
probably not going to happen this merge window)