From 133be0a9e27dc28dacba4b651b8633f1a85eead9 Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: Fri, 5 Aug 2016 14:48:27 +0200
Subject: [PATCH] qemu: domain: Prepare for VCPUs vanishing while libvirt is
 not running

Similarly to devices the guest may allow unplug of the VCPU if libvirt
is down. To avoid problems, refresh the vcpu state on reconnect. Don't
mess with the vcpu state otherwise.
---
 src/qemu/qemu_domain.c  | 9 ++++++++-
 src/qemu/qemu_domain.h  | 3 ++-
 src/qemu/qemu_driver.c  | 4 ++--
 src/qemu/qemu_process.c | 7 +++++--
 4 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index f0ae84e09d..d4f472ba28 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -5764,16 +5764,20 @@ qemuDomainSupportsNewVcpuHotplug(virDomainObjPtr vm)
  * @driver: qemu driver data
  * @vm: domain object
  * @asyncJob: current asynchronous job type
+ * @state: refresh vcpu state
  *
  * Updates vCPU information private data of @vm. Due to historical reasons this
  * function returns success even if some data were not reported by qemu.
  *
+ * If @state is true, the vcpu state is refreshed as reported by the monitor.
+ *
  * Returns 0 on success and -1 on fatal error.
  */
 int
 qemuDomainRefreshVcpuInfo(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,
-                          int asyncJob)
+                          int asyncJob,
+                          bool state)
 {
     virDomainVcpuDefPtr vcpu;
     qemuDomainVcpuPrivatePtr vcpupriv;
@@ -5841,6 +5845,9 @@ qemuDomainRefreshVcpuInfo(virQEMUDriverPtr driver,
         VIR_FREE(vcpupriv->alias);
         VIR_STEAL_PTR(vcpupriv->alias, info[i].alias);
         vcpupriv->enable_id = info[i].id;
+
+        if (hotplug && state)
+            vcpu->online = !!info[i].qom_path;
     }
 
     ret = 0;
diff --git a/src/qemu/qemu_domain.h b/src/qemu/qemu_domain.h
index c95acdfa6d..b4b3daef36 100644
--- a/src/qemu/qemu_domain.h
+++ b/src/qemu/qemu_domain.h
@@ -660,7 +660,8 @@ pid_t qemuDomainGetVcpuPid(virDomainObjPtr vm, unsigned int vcpuid);
 int qemuDomainValidateVcpuInfo(virDomainObjPtr vm);
 int qemuDomainRefreshVcpuInfo(virQEMUDriverPtr driver,
                               virDomainObjPtr vm,
-                              int asyncJob);
+                              int asyncJob,
+                              bool state);
 
 bool qemuDomainSupportsNicdev(virDomainDefPtr def,
                               virDomainNetDefPtr net);
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index a0ac2ef7f5..8ff95f6681 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4640,7 +4640,7 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,
 
     vcpuinfo->online = true;
 
-    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)
+    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE, false) < 0)
         goto cleanup;
 
     if (qemuDomainValidateVcpuInfo(vm) < 0)
@@ -4689,7 +4689,7 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver,
         goto cleanup;
     }
 
-    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)
+    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE, false) < 0)
         goto cleanup;
 
     if (qemuDomainValidateVcpuInfo(vm) < 0) {
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c
index 907da3045a..3cf9d8cd97 100644
--- a/src/qemu/qemu_process.c
+++ b/src/qemu/qemu_process.c
@@ -3354,6 +3354,9 @@ qemuProcessReconnect(void *opaque)
     ignore_value(virSecurityManagerCheckAllLabel(driver->securityManager,
                                                  obj->def));
 
+    if (qemuDomainRefreshVcpuInfo(driver, obj, QEMU_ASYNC_JOB_NONE, true) < 0)
+        goto error;
+
     if (virSecurityManagerReserveLabel(driver->securityManager, obj->def, obj->pid) < 0)
         goto error;
 
@@ -5234,7 +5237,7 @@ qemuProcessLaunch(virConnectPtr conn,
         goto cleanup;
 
     VIR_DEBUG("Refreshing VCPU info");
-    if (qemuDomainRefreshVcpuInfo(driver, vm, asyncJob) < 0)
+    if (qemuDomainRefreshVcpuInfo(driver, vm, asyncJob, false) < 0)
         goto cleanup;
 
     if (qemuDomainValidateVcpuInfo(vm) < 0)
@@ -6029,7 +6032,7 @@ int qemuProcessAttach(virConnectPtr conn ATTRIBUTE_UNUSED,
     }
 
     VIR_DEBUG("Detecting VCPU PIDs");
-    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE) < 0)
+    if (qemuDomainRefreshVcpuInfo(driver, vm, QEMU_ASYNC_JOB_NONE, false) < 0)
         goto error;
 
     if (qemuDomainValidateVcpuInfo(vm) < 0)