s390x/kvm: enable AP instruction interpretation for guest

Let's use the KVM_SET_DEVICE_ATTR ioctl to enable hardware
interpretation of AP instructions executed on the guest.
If the S390_FEAT_AP feature is switched on for the guest,
AP instructions must be interpreted by default; otherwise,
they will be intercepted.

This attribute setting may be overridden by a device. For example,
a device may want to provide AP instructions to the guest (i.e.,
S390_FEAT_AP turned on), but it may want to emulate them. In this
case, the AP instructions executed on the guest must be
intercepted; so when the device is realized, it must disable
interpretation.

Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Tested-by: Pierre Morel <pmorel@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20181010170309.12045-4-akrowiak@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
master
Tony Krowiak 2018-10-10 13:03:05 -04:00 committed by Cornelia Huck
parent c5cd17afdd
commit 1d7db85b61
1 changed files with 19 additions and 0 deletions

View File

@ -2299,11 +2299,26 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model, Error **errp)
error_setg(errp, "KVM: host CPU model could not be identified");
return;
}
/* for now, we can only provide the AP feature with HW support */
if (kvm_vm_check_attr(kvm_state, KVM_S390_VM_CRYPTO,
KVM_S390_VM_CRYPTO_ENABLE_APIE)) {
set_bit(S390_FEAT_AP, model->features);
}
/* strip of features that are not part of the maximum model */
bitmap_and(model->features, model->features, model->def->full_feat,
S390_FEAT_MAX);
}
static void kvm_s390_configure_apie(bool interpret)
{
uint64_t attr = interpret ? KVM_S390_VM_CRYPTO_ENABLE_APIE :
KVM_S390_VM_CRYPTO_DISABLE_APIE;
if (kvm_vm_check_attr(kvm_state, KVM_S390_VM_CRYPTO, attr)) {
kvm_s390_set_attr(attr);
}
}
void kvm_s390_apply_cpu_model(const S390CPUModel *model, Error **errp)
{
struct kvm_s390_vm_cpu_processor prop = {
@ -2353,6 +2368,10 @@ void kvm_s390_apply_cpu_model(const S390CPUModel *model, Error **errp)
if (test_bit(S390_FEAT_CMM, model->features)) {
kvm_s390_enable_cmma();
}
if (test_bit(S390_FEAT_AP, model->features)) {
kvm_s390_configure_apie(true);
}
}
void kvm_s390_restart_interrupt(S390CPU *cpu)