confidential guest support: Rework the "memory-encryption" property

Currently the "memory-encryption" property is only looked at once we
get to kvm_init().  Although protection of guest memory from the
hypervisor isn't something that could really ever work with TCG, it's
not conceptually tied to the KVM accelerator.

In addition, the way the string property is resolved to an object is
almost identical to how a QOM link property is handled.

So, create a new "confidential-guest-support" link property which sets
this QOM interface link directly in the machine.  For compatibility we
keep the "memory-encryption" property, but now implemented in terms of
the new property.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>

1 files changed, 3 insertions, 2 deletions

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 3526e88b6c..88a6b8c19e 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -2184,8 +2184,9 @@ static int kvm_init(MachineState *ms)
      * if memory encryption object is specified then initialize the memory
      * encryption context.
      */
-    if (ms->memory_encryption) {
-        ret = sev_guest_init(ms->memory_encryption);
+    if (ms->cgs) {
+        /* FIXME handle mechanisms other than SEV */
+        ret = sev_kvm_init(ms->cgs);
         if (ret < 0) {
             goto err;
         }