From 8cf65dabf2f14aee2aced27eb268524279105b2d Mon Sep 17 00:00:00 2001
From: Peter Krempa <pkrempa@redhat.com>
Date: Thu, 29 Oct 2015 15:49:26 +0100
Subject: [PATCH] qemu: cpu hotplug: Fix error handling logic

The cpu hotplug helper functions used negative error handling in a part
of them, although some code that was added later didn't properly set the
error codes in some cases. This would cause improper error messages in
cases where we couldn't modify the numa cpu mask and a few other cases.

Fix the logic by converting it to the regularly used pattern.
---
 src/qemu/qemu_driver.c | 33 ++++++++++++---------------------
 1 file changed, 12 insertions(+), 21 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 1e606a62f..bbd43f494 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4721,10 +4721,6 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,
         vcpus++;
     }
 
-    /* hotplug succeeded */
-
-    ret = 0;
-
     /* After hotplugging the CPUs we need to re-detect threads corresponding
      * to the virtual CPUs. Some older versions don't provide the thread ID
      * or don't have the "info cpus" command (and they don't support multiple
@@ -4732,12 +4728,12 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,
      * fatal */
     if ((ncpupids = qemuMonitorGetCPUInfo(priv->mon, &cpupids)) <= 0) {
         virResetLastError();
+        ret = 0;
         goto exit_monitor;
     }
-    if (qemuDomainObjExitMonitor(driver, vm) < 0) {
-        ret = -1;
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
         goto cleanup;
-    }
 
     if (ncpupids != vcpus) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
@@ -4745,7 +4741,6 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,
                          "got %d, wanted %d"),
                        ncpupids, vcpus);
         vcpus = oldvcpus;
-        ret = -1;
         goto cleanup;
     }
 
@@ -4771,15 +4766,12 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,
         if (vm->def->cpumask) {
             if (qemuDomainHotplugAddPin(vm->def->cpumask, i,
                                         &vm->def->cputune.vcpupin,
-                                        &vm->def->cputune.nvcpupin) < 0) {
-                ret = -1;
+                                        &vm->def->cputune.nvcpupin) < 0)
                 goto cleanup;
-            }
+
             if (qemuDomainHotplugPinThread(vm->def->cpumask, i, cpupids[i],
-                                           cgroup_vcpu) < 0) {
-                ret = -1;
+                                           cgroup_vcpu) < 0)
                 goto cleanup;
-            }
         }
         virCgroupFree(&cgroup_vcpu);
 
@@ -4794,6 +4786,8 @@ qemuDomainHotplugAddVcpu(virQEMUDriverPtr driver,
     priv->vcpupids = cpupids;
     cpupids = NULL;
 
+    ret = 0;
+
  cleanup:
     VIR_FREE(cpupids);
     VIR_FREE(mem_mask);
@@ -4841,8 +4835,6 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver,
         vcpus--;
     }
 
-    ret = 0;
-
     /* After hotplugging the CPUs we need to re-detect threads corresponding
      * to the virtual CPUs. Some older versions don't provide the thread ID
      * or don't have the "info cpus" command (and they don't support multiple
@@ -4850,19 +4842,17 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver,
      * fatal */
     if ((ncpupids = qemuMonitorGetCPUInfo(priv->mon, &cpupids)) <= 0) {
         virResetLastError();
+        ret = 0;
         goto exit_monitor;
     }
-    if (qemuDomainObjExitMonitor(driver, vm) < 0) {
-        ret = -1;
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
         goto cleanup;
-    }
 
     /* check if hotunplug has failed */
     if (ncpupids == oldvcpus) {
         virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
                        _("qemu didn't unplug the vCPUs properly"));
         vcpus = oldvcpus;
-        ret = -1;
         goto cleanup;
     }
 
@@ -4872,7 +4862,6 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver,
                          "got %d, wanted %d"),
                        ncpupids, vcpus);
         vcpus = oldvcpus;
-        ret = -1;
         goto cleanup;
     }
 
@@ -4892,6 +4881,8 @@ qemuDomainHotplugDelVcpu(virQEMUDriverPtr driver,
     priv->vcpupids = cpupids;
     cpupids = NULL;
 
+    ret = 0;
+
  cleanup:
     VIR_FREE(cpupids);
     if (virDomainObjIsActive(vm) &&
-- 
2.39.5