KVM: do not allow setting properties at runtime

Only allow accelerator properties to be set when the
accelerator is being created.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 12 insertions, 1 deletions

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 4e0168e88b..54c0860979 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -2017,7 +2017,6 @@ static int kvm_init(MachineState *ms)
     QTAILQ_INIT(&s->kvm_sw_breakpoints);
 #endif
     QLIST_INIT(&s->kvm_parked_vcpus);
-    s->vmfd = -1;
     s->fd = qemu_open_old("/dev/kvm", O_RDWR);
     if (s->fd == -1) {
         fprintf(stderr, "Could not access KVM kernel module: %m\n");
@@ -3112,6 +3111,11 @@ static void kvm_set_kvm_shadow_mem(Object *obj, Visitor *v,
     KVMState *s = KVM_STATE(obj);
     int64_t value;
 
+    if (s->fd != -1) {
+        error_setg(errp, "Cannot set properties after the accelerator has been initialized");
+        return;
+    }
+
     if (!visit_type_int(v, name, &value, errp)) {
         return;
     }
@@ -3126,6 +3130,11 @@ static void kvm_set_kernel_irqchip(Object *obj, Visitor *v,
     KVMState *s = KVM_STATE(obj);
     OnOffSplit mode;
 
+    if (s->fd != -1) {
+        error_setg(errp, "Cannot set properties after the accelerator has been initialized");
+        return;
+    }
+
     if (!visit_type_OnOffSplit(v, name, &mode, errp)) {
         return;
     }
@@ -3172,6 +3181,8 @@ static void kvm_accel_instance_init(Object *obj)
 {
     KVMState *s = KVM_STATE(obj);
 
+    s->fd = -1;
+    s->vmfd = -1;
     s->kvm_shadow_mem = -1;
     s->kernel_irqchip_allowed = true;
     s->kernel_irqchip_split = ON_OFF_AUTO_AUTO;