Messages in this thread | | | Date | Wed, 15 Jun 2022 13:39:01 +0200 | From | Juergen Gross <> | Subject | Re: [PATCH] xen: don't require virtio with grants for non-PV guests |
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On 15.06.22 13:28, Christoph Hellwig wrote: > On Wed, Jun 15, 2022 at 01:26:27PM +0200, Juergen Gross wrote: >> On 15.06.22 13:24, Christoph Hellwig wrote: >>> I don't think this command line mess is a good idea. Instead the >>> brand new grant devices need to be properly advertised in the device >>> tree, and any device that isn't a grant device doesn't need >>> VIRTIO_F_ACCESS_PLATFORM. No need for a command line or user >>> intervention. >> >> And on x86? > > ACPI tables or whatever mechanism you otherwise use to advertise grant > based DMA. But that is irrelevant for now, as the code in mainline > only supports DT on arm/arm64 anyay.
No, it doesn't. I'm working on a qemu patch series enabling the qemu based backends to support grants with virtio. The code is working fine on x86, too (apart from the fact that the backends aren't ready yet).
I'd be fine to just drop the command line parameter, but I think a guest admin should be able to specify that he doesn't want the backend to be able to map arbitrary memory of the guest in order to add another line of defense.
Juergen [unhandled content-type:application/pgp-keys][unhandled content-type:application/pgp-signature] | |