From: Christian Borntraeger <borntrae...@de.ibm.com>
The unpack facility is an indication that diagnose 308 subcodes 8-10
are available to the guest. That means, that the guest can put itself
into protected mode.
Once it is in protected mode, the hardware stops any attempt of VM
introspection by the hypervisor.
Some features are currently not supported in protected mode:
* Passthrough devices
* Migration
* Huge page backings
Signed-off-by: Christian Borntraeger <borntrae...@de.ibm.com>
Reviewed-by: David Hildenbrand <da...@redhat.com>
---
target/s390x/gen-features.c | 1 +
target/s390x/kvm.c | 5 +++++
2 files changed, 6 insertions(+)
diff --git a/target/s390x/gen-features.c b/target/s390x/gen-features.c
index 6278845b12b8dee8..8ddeebc54419a3e2 100644
--- a/target/s390x/gen-features.c
+++ b/target/s390x/gen-features.c
@@ -562,6 +562,7 @@ static uint16_t full_GEN15_GA1[] = {
S390_FEAT_GROUP_MSA_EXT_9,
S390_FEAT_GROUP_MSA_EXT_9_PCKMO,
S390_FEAT_ETOKEN,
+ S390_FEAT_UNPACK,
};
/* Default features (in order of release)
diff --git a/target/s390x/kvm.c b/target/s390x/kvm.c
index ff6027036ec2f14a..e11e895a3d9038bb 100644
--- a/target/s390x/kvm.c
+++ b/target/s390x/kvm.c
@@ -2403,6 +2403,11 @@ void kvm_s390_get_host_cpu_model(S390CPUModel *model,
Error **errp)
clear_bit(S390_FEAT_BPB, model->features);
}
+ /* we do have the IPL enhancements */
+ if (cap_protected) {
+ set_bit(S390_FEAT_UNPACK, model->features);
+ }
+
/* We emulate a zPCI bus and AEN, therefore we don't need HW support */
set_bit(S390_FEAT_ZPCI, model->features);
set_bit(S390_FEAT_ADAPTER_EVENT_NOTIFICATION, model->features);
--
2.25.1
