(sorry for the formatting)

On Thu, 7 Feb 2019, 11:37 Roger Pau Monné, <roger.pau@citrix.com> wrote:

> On Thu, Feb 07, 2019 at 11:42:16AM +0200, Andrii Anisov wrote:
> > Hello All,
> >
> > On 06.02.19 23:03, Stefano Stabellini wrote:
> > > That's great. Could you or Roger take care of cleaning up the patch and
> > > properly submitting it to the list?
> >
> > I can take it for cleaning up.
> >
> > > And also double check that it won't
> > > break any guests (at least the ones we know about: Linux and Windows on
> > > x86).
> >
> > I'm not sure I could properly check it for x86. For sure can't do that
> for windows guest.
>
> I've been thinking about this with other Citrix folks, and I'm not
> sure the proposed patch is a good solution. It's not possible for us
> to know whether there's a kernel somewhere relying on changing the
> virtual address of the runtime state area without issuing a new
> hypercall.
>
> If such kernel existed by making this change we would introduce random
> memory corruption to that kernel, which would be very hard to track
> and considered a regression.
>
> I think the best way to move forward is to pick my patch and introduce
> a new hypercall that instead of a virtual address takes a guest
> physical address. Will you be OK with this Andrii
>

In that case I would prefer if we don't keep the runstate mapped.

Cheers,