Messages in this thread | | | Date | Fri, 17 Dec 2021 12:13:28 -0500 | Subject | Re: [PATCH 16/32] KVM: s390: expose the guest zPCI interpretation facility | From | Matthew Rosato <> |
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On 12/17/21 11:58 AM, Christian Borntraeger wrote: > > > Am 17.12.21 um 16:19 schrieb Matthew Rosato: >> On 12/17/21 10:05 AM, Christian Borntraeger wrote: >>> >>> >>> Am 07.12.21 um 21:57 schrieb Matthew Rosato: >>>> This facility will be used to enable interpretive execution of zPCI >>>> instructions. >>>> >>>> Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com> >>>> --- >>>> arch/s390/kvm/kvm-s390.c | 4 ++++ >>>> 1 file changed, 4 insertions(+) >>>> >>>> diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c >>>> index c8fe9b7c2395..09991d05c871 100644 >>>> --- a/arch/s390/kvm/kvm-s390.c >>>> +++ b/arch/s390/kvm/kvm-s390.c >>>> @@ -2751,6 +2751,10 @@ int kvm_arch_init_vm(struct kvm *kvm, >>>> unsigned long type) >>>> set_kvm_facility(kvm->arch.model.fac_mask, 147); >>>> set_kvm_facility(kvm->arch.model.fac_list, 147); >>>> } >>>> + if (sclp.has_zpci_interp && test_facility(69)) { >>>> + set_kvm_facility(kvm->arch.model.fac_mask, 69); >>>> + set_kvm_facility(kvm->arch.model.fac_list, 69); >>>> + } >>> >>> >>> Do we need the setting of these stfle bits somewhere? I think QEMU >>> sets them as well for the guest. > We only need this when the kernel >>> probes for this (test_kvm_facility) >>> But then the question is, shouldnt >>> we then simply check for sclp bits in those places? >>> See also patch 19. We need to build it in a way that allows VSIE >>> support later on. >>> >> >> Right, so this currently sets the facility bits but we don't set the >> associated guest SCLP bits. I guess since we are not enabling for >> VSIE now it would make sense to not set either. >> >> So then just to confirm we are on the same page: I will drop these >> patches 16-18 and leave the kvm facilities unset until we wish to >> enable VSIE. And then also make sure we are checking sclp bits (e.g. >> patch 19). OK? > > Right drop these patches and change patch 19. When we later enable VSIE > we need QEMU to set the sclp bits. Not sure, does this work as of today > or do we need additional vsie changes (I would assume so)?
No, we will need some additional work to be able to enable for VSIE (e.g. adapter interrupt source ID)
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