[libvirt] [PATCH 4/5] qemu: hotplug: Add validation for coldplug of individual vcpus

[Peter Krempa]

Validate that users don't try to disable vcpu 0 and reject attempt to
modify a vcpu to the state it is currently in.
---
 src/qemu/qemu_hotplug.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index 5488b1dd4..18a8df33a 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -5875,6 +5875,37 @@ qemuDomainFilterHotplugVcpuEntities(virDomainDefPtr def,
 }


+static int
+qemuDomainVcpuValidateConfig(virDomainDefPtr def,
+                             virBitmapPtr map,
+                             bool state)
+{
+    virDomainVcpuDefPtr vcpu;
+    ssize_t next = -1;
+
+    /* vcpu 0 can't be disabled */
+    if (!state && virBitmapIsBitSet(map, 0)) {
+        virReportError(VIR_ERR_INVALID_ARG, "%s",
+                       _("vCPU '0' must be enabled"));
+        return -1;
+    }
+
+    /* make sure that all selected vcpus are in the correct state */
+    while ((next = virBitmapNextSetBit(map, next)) >= 0) {
+        if (!(vcpu = virDomainDefGetVcpu(def, next)))
+            continue;
+
+        if (vcpu->online == state) {
+            virReportError(VIR_ERR_INVALID_ARG,
+                           _("vcpu '%zd' is already in requested state"), next);
+            return -1;
+        }
+    }
+
+    return 0;
+}
+
+
 int
 qemuDomainSetVcpuInternal(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,
@@ -5909,6 +5940,11 @@ qemuDomainSetVcpuInternal(virQEMUDriverPtr driver,
         }
     }

+    if (persistentDef) {
+        if (qemuDomainVcpuValidateConfig(persistentDef, map, state) < 0)
+            goto cleanup;
+    }
+
     if (livevcpus &&
         qemuDomainSetVcpusLive(driver, cfg, vm, livevcpus, state) < 0)
         goto cleanup;
-- 
2.12.2