Re: [PATCH 3/3] arm, arm64: KVM: handle potential incoherency of readonly memslots

Laszlo Ersek
2014-11-22T10:27:26Z

On 11/22/14 11:18, Christoffer Dall wrote:
> On Fri, Nov 21, 2014 at 05:50:43PM -0800, Mario Smarduch wrote:

>> But virtio writes to guest memory directly and that appears to
>> work just fine. I read that code sometime back, and will need to revisit.
>>
> In any case, that's a QEMU implementation issue and nothing the kernel
> needs to be concerned with.

(Let's call it "qemu implementation detail" -- there's no "issue". The
reason virtio works is not by incident, it has a known cause. As
confirmed by Peter, there's no problem with the virtio buffers because
the guest doesn't mark them as uncacheable, so *all* accesses go through
the dcache.)

Thanks
Laszlo