Don't ignore guest CPU selection when unsupported by HV

When qemu libvirt driver doesn't support guest CPU selection with given
qemu binary, guests requiring specific CPU should fail to start instead
of being silently supplied with a default CPU.

diff --git a/src/qemu/qemu_conf.c b/src/qemu/qemu_conf.c
index 538784a83d39e93967f9bdd4dfe468cad6ed5b05..f56a7ef55cab63c52136db5545bbd0ce8039adb2 100644 (file)
--- a/src/qemu/qemu_conf.c
+++ b/src/qemu/qemu_conf.c
@@ -3249,9 +3249,16 @@ qemuBuildCpuArgStr(const struct qemud_driver *driver,
     virBuffer buf = VIR_BUFFER_INITIALIZER;
     int i;
 
-    if (def->cpu && def->cpu->model
-        && qemudProbeCPUModels(emulator, ut->machine, &ncpus, &cpus) < 0)
-        goto cleanup;
+    if (def->cpu && def->cpu->model) {
+        if (qemudProbeCPUModels(emulator, ut->machine, &ncpus, &cpus) < 0)
+            goto cleanup;
+
+        if (!ncpus || !host) {
+            qemuReportError(VIR_ERR_NO_SUPPORT, "%s",
+                            _("CPU specification not supported by hypervisor"));
+            goto cleanup;
+        }
+    }
 
     if (ncpus > 0 && host) {
         virCPUCompareResult cmp;