Re: [PATCH v9 05/22] KVM: s390: vsie: simulate VCPU SIE entry/exit

[Tony Krowiak]

On 08/14/2018 04:50 AM, Cornelia Huck wrote:
> On Mon, 13 Aug 2018 17:48:02 -0400
> Tony Krowiak <akrowiak@xxxxxxxxxxxxxxxxxx> wrote:
>
> > From: David Hildenbrand <david@xxxxxxxxxx>
> >
> > VCPU requests and VCPU blocking right now don't take care of the vSIE
> > (as it was not necessary until now). But we want to have VCPU requests
> > that will also be handled before running the vSIE again.
> >
> > So let's simulate a SIE entry when entering the vSIE loop and check
> > for PROG_ flags. The existing infrastructure (e.g. exit_sie()) will then
> > detect that the SIE (in form of the vSIE execution loop) is running and
> > properly kick the vSIE CPU, resulting in it leaving the vSIE loop and
> > therefore the vSIE interception handler, allowing it to handle VCPU
> > requests.
> >
> > E.g. if we want to modify the crycb of the VCPU and make sure that any
> > masks also get applied to the VSIE crycb shadow (which uses masks from the
> > VCPU crycb), we will need a way to hinder the vSIE from running and make
> > sure to process the updated crycb before reentering the vSIE again.
> >
> > Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
> > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
> > Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
> > ---
> >   arch/s390/kvm/kvm-s390.c |    9 ++++++++-
> >   arch/s390/kvm/kvm-s390.h |    1 +
> >   arch/s390/kvm/vsie.c     |   20 ++++++++++++++++++--
> >   3 files changed, 27 insertions(+), 3 deletions(-)
> I think that is the RFC version of David's patch, not the v1? Again,
> not really relevant for reviewing, but I hope that you test the final
> version.

Will do.

>