On Wed, 19 Sep 2018 12:56:53 -0400
Collin Walling <walling@xxxxxxxxxxxxx> wrote:
> On 09/19/2018 05:37 AM, Cornelia Huck wrote:
> > On Fri, 31 Aug 2018 12:51:18 -0400
> > Collin Walling <walling@xxxxxxxxxxxxx> wrote:
> >
> >> The diagnose 318 instruction is a privileged instruction that must be
> >> interpreted by SIE and handled via KVM.
> >>
> >> The control program name and version codes (CPNC and CPVC) set by this
> >> instruction are saved to the kvm->arch struct. The CPNC is also set in
> >> the SIE control block of all VCPUs. The new kvm_s390_set_misc interface
> >> is introduced for migration.
> >>
> >> Signed-off-by: Collin Walling <walling@xxxxxxxxxxxxx>
> >> Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
> >> ---
> >> arch/s390/include/asm/kvm_host.h | 6 ++-
> >> arch/s390/include/uapi/asm/kvm.h | 5 ++
> >> arch/s390/kvm/diag.c | 16 ++++++
> >> arch/s390/kvm/kvm-s390.c | 90 ++++++++++++++++++++++++++++++++++
> >> arch/s390/kvm/kvm-s390.h | 1 +
> >> tools/arch/s390/include/uapi/asm/kvm.h | 1 +
> >> 6 files changed, 118 insertions(+), 1 deletion(-)
> >>
> >
> >> @@ -2568,6 +2655,9 @@ void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
> >> vcpu->arch.sie_block->epoch = vcpu->kvm->arch.epoch;
> >> vcpu->arch.sie_block->epdx = vcpu->kvm->arch.epdx;
> >> preempt_enable();
> >> +
> >> + vcpu->arch.sie_block->cpnc = vcpu->kvm->arch.cpnc;
> >
> > Any reason why you set this _after_ the preempt_enable()?
> >
>
> I didn't consider setting this value as time-critical as the TOD-Clock values. I guess
> it doesn't hurt to throw the cpnc in there, too?
_postcreate is probably not time-critical at all... just keep setting
up all of the fields in one place?
>
> >> +
> >> mutex_unlock(&vcpu->kvm->lock);
> >> if (!kvm_is_ucontrol(vcpu->kvm)) {
> >> vcpu->arch.gmap = vcpu->kvm->arch.gmap;
> >
>
>
