aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/kvm/vsie.c
diff options
context:
space:
mode:
authorChristian Borntraeger <borntraeger@de.ibm.com>2018-01-17 14:44:34 +0100
committerRadim Krčmář <rkrcmar@redhat.com>2018-01-20 17:30:47 +0100
commit35b3fde6203b932b2b1a5b53b3d8808abc9c4f60 (patch)
tree872a70372b05ddf324c5cc943efedf0ddd722b96 /arch/s390/kvm/vsie.c
parentMerge tag 'kvm-ppc-cve-4.15-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc (diff)
downloadlinux-dev-35b3fde6203b932b2b1a5b53b3d8808abc9c4f60.tar.xz
linux-dev-35b3fde6203b932b2b1a5b53b3d8808abc9c4f60.zip
KVM: s390: wire up bpb feature
The new firmware interfaces for branch prediction behaviour changes are transparently available for the guest. Nevertheless, there is new state attached that should be migrated and properly resetted. Provide a mechanism for handling reset, migration and VSIE. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> [Changed capability number to 152. - Radim] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/s390/kvm/vsie.c')
-rw-r--r--arch/s390/kvm/vsie.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 5d6ae0326d9e..751348348477 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -223,6 +223,12 @@ static void unshadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
memcpy(scb_o->gcr, scb_s->gcr, 128);
scb_o->pp = scb_s->pp;
+ /* branch prediction */
+ if (test_kvm_facility(vcpu->kvm, 82)) {
+ scb_o->fpf &= ~FPF_BPBC;
+ scb_o->fpf |= scb_s->fpf & FPF_BPBC;
+ }
+
/* interrupt intercept */
switch (scb_s->icptcode) {
case ICPT_PROGI:
@@ -265,6 +271,7 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
scb_s->ecb3 = 0;
scb_s->ecd = 0;
scb_s->fac = 0;
+ scb_s->fpf = 0;
rc = prepare_cpuflags(vcpu, vsie_page);
if (rc)
@@ -324,6 +331,9 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
prefix_unmapped(vsie_page);
scb_s->ecb |= scb_o->ecb & ECB_TE;
}
+ /* branch prediction */
+ if (test_kvm_facility(vcpu->kvm, 82))
+ scb_s->fpf |= scb_o->fpf & FPF_BPBC;
/* SIMD */
if (test_kvm_facility(vcpu->kvm, 129)) {
scb_s->eca |= scb_o->eca & ECA_VX;