Re: [PATCH v1 ppc-for-5.0 2/2] ppc/spapr: Support reboot of secure pseries guest

[Bharata B Rao <bharata@linux.ibm.com>]

On Tue, Dec 10, 2019 at 02:28:51PM +1100, David Gibson wrote:
> On Mon, Dec 09, 2019 at 12:30:12PM +0530, Bharata B Rao wrote:
> > A pseries guest can be run as a secure guest on Ultravisor-enabled
> > POWER platforms. When such a secure guest is reset, we need to
> > release/reset a few resources both on ultravisor and hypervisor side.
> > This is achieved by invoking this new ioctl KVM_PPC_SVM_OFF from the
> > machine reset path.
> > 
> > As part of this ioctl, the secure guest is essentially transitioned
> > back to normal mode so that it can reboot like a regular guest and
> > become secure again.
> > 
> > This ioctl has no effect when invoked for a normal guest.
> > 
> > Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
> > ---
> >  hw/ppc/spapr.c       | 1 +
> >  target/ppc/kvm.c     | 7 +++++++
> >  target/ppc/kvm_ppc.h | 6 ++++++
> >  3 files changed, 14 insertions(+)
> > 
> > diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
> > index f11422fc41..4c7ad3400d 100644
> > --- a/hw/ppc/spapr.c
> > +++ b/hw/ppc/spapr.c
> > @@ -1597,6 +1597,7 @@ static void spapr_machine_reset(MachineState *machine)
> >      void *fdt;
> >      int rc;
> >  
> > +    kvmppc_svm_off();
> 
> If you're going to have this return an error value, you should really
> check it here.

I could, by spapr_machine_reset() and the callers don't propagate the
errors up. So may be I could print a warning instead when ioctl fails?

Regards,
Bharata.