Enabling AP-passthrough(AP-pt) for PV-guest via using the new CPU
features for PV-AP-pt of kvm.
As usual QEMU first checks which CPU features are available and then
sets them if available and selected by user. An additional check is done
to verify that PV-AP can only be enabled if "regular" AP-pt is enabled
as well. Note that KVM itself does not enforce this restriction.
If regular AP-pt is enabled and kvm/firmware supports PV-AP-pt it is
also turned on by default.
Signed-off-by: Steffen Eiden <sei...@linux.ibm.com>
---
target/s390x/cpu_features.h | 1 +
target/s390x/cpu_features_def.h.inc | 4 ++
target/s390x/cpu_models.c | 2 +
target/s390x/gen-features.c | 4 ++
target/s390x/kvm/kvm.c | 73 +++++++++++++++++++++++++++++
5 files changed, 84 insertions(+)
diff --git a/target/s390x/cpu_features.h b/target/s390x/cpu_features.h
index 87463f064d..40928c60e9 100644
--- a/target/s390x/cpu_features.h
+++ b/target/s390x/cpu_features.h
@@ -43,6 +43,7 @@ typedef enum {
S390_FEAT_TYPE_KDSA,
S390_FEAT_TYPE_SORTL,
S390_FEAT_TYPE_DFLTCC,
+ S390_FEAT_TYPE_UV_CALL,
} S390FeatType;
/* Definition of a CPU feature */
diff --git a/target/s390x/cpu_features_def.h.inc
b/target/s390x/cpu_features_def.h.inc
index e3cfe63735..4b659d4064 100644
--- a/target/s390x/cpu_features_def.h.inc
+++ b/target/s390x/cpu_features_def.h.inc
@@ -379,3 +379,7 @@ DEF_FEAT(DEFLATE_GHDT, "dfltcc-gdht", DFLTCC, 1, "DFLTCC
GDHT")
DEF_FEAT(DEFLATE_CMPR, "dfltcc-cmpr", DFLTCC, 2, "DFLTCC CMPR")
DEF_FEAT(DEFLATE_XPND, "dfltcc-xpnd", DFLTCC, 4, "DFLTCC XPND")
DEF_FEAT(DEFLATE_F0, "dfltcc-f0", DFLTCC, 192, "DFLTCC format 0
parameter-block")
+
+/* Features exposed via the UV-CALL instruction */
+DEF_FEAT(UV_CALL_AP, "appv", UV_CALL, 4, "AP instructions installed for secure
guests")
+DEF_FEAT(UV_CALL_AP_INTR, "appvi", UV_CALL, 5, "AP instructions interpretion
for secure guests")
diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
index ae8880e81d..6d703b3c55 100644
--- a/target/s390x/cpu_models.c
+++ b/target/s390x/cpu_models.c
@@ -483,6 +483,8 @@ static void check_consistency(const S390CPUModel *model)
{ S390_FEAT_DIAG_318, S390_FEAT_EXTENDED_LENGTH_SCCB },
{ S390_FEAT_NNPA, S390_FEAT_VECTOR },
{ S390_FEAT_RDP, S390_FEAT_LOCAL_TLB_CLEARING },
+ { S390_FEAT_UV_CALL_AP, S390_FEAT_AP },
+ { S390_FEAT_UV_CALL_AP_INTR, S390_FEAT_UV_CALL_AP },
};
int i;
diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
index 1e3b7c0dc9..0220864d89 100644
--- a/target/s390x/gen-features.c
+++ b/target/s390x/gen-features.c
@@ -576,6 +576,8 @@ static uint16_t full_GEN16_GA1[] = {
S390_FEAT_RDP,
S390_FEAT_PAI,
S390_FEAT_PAIE,
+ S390_FEAT_UV_CALL_AP,
+ S390_FEAT_UV_CALL_AP_INTR,
};
@@ -671,6 +673,8 @@ static uint16_t default_GEN16_GA1[] = {
S390_FEAT_RDP,
S390_FEAT_PAI,
S390_FEAT_PAIE,
+ S390_FEAT_UV_CALL_AP,
+ S390_FEAT_UV_CALL_AP_INTR,
};
/* QEMU (CPU model) features */
diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c
index bd62a7f606..cf11bfb0fa 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -2301,6 +2301,39 @@ static bool ap_available(void)
return kvm_vm_check_attr(kvm_state, KVM_S390_VM_CRYPTO,
KVM_S390_VM_CRYPTO_ENABLE_APIE);
}
+static bool uv_feat_supported(void)
+{
+ return kvm_vm_check_attr(
+ kvm_state, KVM_S390_VM_CPU_MODEL,
KVM_S390_VM_CPU_PROCESSOR_UV_FEAT_GUEST);
+}
+
+static int query_uv_feat_guest(S390FeatBitmap features)
+{
+ struct kvm_s390_vm_cpu_uv_feat prop = {};
+ struct kvm_device_attr attr = {
+ .group = KVM_S390_VM_CPU_MODEL,
+ .attr = KVM_S390_VM_CPU_MACHINE_UV_FEAT_GUEST,
+ .addr = (uint64_t) &prop,
+ };
+ int rc;
+
+ if (!uv_feat_supported())
+ return 0;
+
+ rc = kvm_vm_ioctl(kvm_state, KVM_GET_DEVICE_ATTR, &attr);
+ if (rc) {
+ return rc;
+ }
+
+ if (ap_available()) {
+ if (prop.ap)
+ set_bit(S390_FEAT_UV_CALL_AP, features);
+ if (prop.ap_intr)
+ set_bit(S390_FEAT_UV_CALL_AP_INTR, features);
+ }
+ return 0;
+}
+
static int kvm_to_feat[][2] = {
{ KVM_S390_VM_CPU_FEAT_ESOP, S390_FEAT_ESOP },
{ KVM_S390_VM_CPU_FEAT_SIEF2, S390_FEAT_SIE_F2 },
@@ -2495,11 +2528,44 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model,
Error **errp)
set_bit(S390_FEAT_DIAG_318, model->features);
}
+ /* Test for Ultravisor features that influence secure guest behavior */
+ query_uv_feat_guest(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 bool ap_enabled(const S390FeatBitmap features)
+{
+ return test_bit(S390_FEAT_AP, features);
+}
+
+static int configure_uv_feat_guest(const S390FeatBitmap features, bool
interpret)
+{
+
+ struct kvm_s390_vm_cpu_uv_feat uv_feat = {};
+ struct kvm_device_attr attribute = {
+ .group = KVM_S390_VM_CPU_MODEL,
+ .attr = KVM_S390_VM_CPU_PROCESSOR_UV_FEAT_GUEST,
+ .addr = (__u64)&uv_feat,
+ };
+
+ if (!uv_feat_supported())
+ return 0;
+
+ if (ap_enabled(features)) {
+ if (test_bit(S390_FEAT_UV_CALL_AP, features)) {
+ uv_feat.ap = 1;
+ }
+ if (test_bit(S390_FEAT_UV_CALL_AP_INTR, features) && interpret) {
+ uv_feat.ap_intr = 1;
+ }
+ }
+
+ return kvm_vm_ioctl(kvm_state, KVM_SET_DEVICE_ATTR, &attribute);
+}
+
static void kvm_s390_configure_apie(bool interpret)
{
uint64_t attr = interpret ? KVM_S390_VM_CRYPTO_ENABLE_APIE :
@@ -2563,6 +2629,13 @@ void kvm_s390_apply_cpu_model(const S390CPUModel *model,
Error **errp)
if (ap_enabled(model->features)) {
kvm_s390_configure_apie(true);
}
+
+ /* configure uv features for the guest indicated via query / test_bit*/
+ rc = configure_uv_feat_guest(model->features, true);
+ if (rc) {
+ error_setg(errp, "KVM: Error configuring CPU UV features %d", rc);
+ return;
+ }
}
void kvm_s390_restart_interrupt(S390CPU *cpu)
--
2.40.1
