diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index f16518b020..181820f02a 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1289,7 +1289,7 @@ virDomainDefSetVcpusMax(virDomainDefPtr def,
                         unsigned int maxvcpus)
 {
     if (maxvcpus < def->vcpus)
-        def->vcpus = maxvcpus;
+        virDomainDefSetVcpus(def, maxvcpus);
 
     def->maxvcpus = maxvcpus;
 
@@ -1311,6 +1311,16 @@ virDomainDefGetVcpusMax(const virDomainDef *def)
 }
 
 
+int
+virDomainDefSetVcpus(virDomainDefPtr def,
+                     unsigned int vcpus)
+{
+    def->vcpus = vcpus;
+
+    return 0;
+}
+
+
 virDomainDiskDefPtr
 virDomainDiskDefNew(virDomainXMLOptionPtr xmlopt)
 {
@@ -14402,6 +14412,7 @@ virDomainVcpuParse(virDomainDefPtr def,
     int n;
     char *tmp = NULL;
     unsigned int maxvcpus;
+    unsigned int vcpus;
     int ret = -1;
 
     if ((n = virXPathUInt("string(./vcpu[1])", ctxt, &maxvcpus)) < 0) {
@@ -14417,16 +14428,19 @@ virDomainVcpuParse(virDomainDefPtr def,
     if (virDomainDefSetVcpusMax(def, maxvcpus) < 0)
         goto cleanup;
 
-    if ((n = virXPathUInt("string(./vcpu[1]/@current)", ctxt, &def->vcpus)) < 0) {
+    if ((n = virXPathUInt("string(./vcpu[1]/@current)", ctxt, &vcpus)) < 0) {
         if (n == -2) {
             virReportError(VIR_ERR_XML_ERROR, "%s",
                            _("current vcpus count must be an integer"));
             goto cleanup;
         }
 
-        def->vcpus = maxvcpus;
+        vcpus = maxvcpus;
     }
 
+    if (virDomainDefSetVcpus(def, vcpus) < 0)
+        goto cleanup;
+
     if (maxvcpus < def->vcpus) {
         virReportError(VIR_ERR_INTERNAL_ERROR,
                        _("maxvcpus must not be less than current vcpus "
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index cbdb417b98..e1d5054e99 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -2346,6 +2346,7 @@ struct _virDomainDef {
 int virDomainDefSetVcpusMax(virDomainDefPtr def, unsigned int vcpus);
 bool virDomainDefHasVcpusOffline(const virDomainDef *def);
 unsigned int virDomainDefGetVcpusMax(const virDomainDef *def);
+int virDomainDefSetVcpus(virDomainDefPtr def, unsigned int vcpus);
 
 unsigned long long virDomainDefGetMemoryInitial(const virDomainDef *def);
 void virDomainDefSetMemoryTotal(virDomainDefPtr def, unsigned long long size);
diff --git a/src/hyperv/hyperv_driver.c b/src/hyperv/hyperv_driver.c
index 699435ceb2..6ce3522175 100644
--- a/src/hyperv/hyperv_driver.c
+++ b/src/hyperv/hyperv_driver.c
@@ -877,7 +877,10 @@ hypervDomainGetXMLDesc(virDomainPtr domain, unsigned int flags)
                                 processorSettingData->data->VirtualQuantity) < 0)
         goto cleanup;
 
-    def->vcpus = processorSettingData->data->VirtualQuantity;
+    if (virDomainDefSetVcpus(def,
+                             processorSettingData->data->VirtualQuantity) < 0)
+        goto cleanup;
+
     def->os.type = VIR_DOMAIN_OSTYPE_HVM;
 
     /* FIXME: devices section is totally missing */
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index a164798bbf..7726eb3d82 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -232,6 +232,7 @@ virDomainDefParseString;
 virDomainDefPostParse;
 virDomainDefSetMemoryInitial;
 virDomainDefSetMemoryTotal;
+virDomainDefSetVcpus;
 virDomainDefSetVcpusMax;
 virDomainDeleteConfig;
 virDomainDeviceAddressIsValid;
diff --git a/src/libxl/libxl_driver.c b/src/libxl/libxl_driver.c
index 77d290afc1..b5e8a7a9c4 100644
--- a/src/libxl/libxl_driver.c
+++ b/src/libxl/libxl_driver.c
@@ -555,7 +555,8 @@ libxlAddDom0(libxlDriverPrivatePtr driver)
     if (virDomainDefSetVcpusMax(vm->def, d_info.vcpu_max_id + 1))
         goto cleanup;
 
-    vm->def->vcpus = d_info.vcpu_online;
+    if (virDomainDefSetVcpus(vm->def, d_info.vcpu_online) < 0)
+        goto cleanup;
     vm->def->mem.cur_balloon = d_info.current_memkb;
     virDomainDefSetMemoryTotal(vm->def, d_info.max_memkb);
 
@@ -2191,7 +2192,8 @@ libxlDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
         break;
 
     case VIR_DOMAIN_VCPU_CONFIG:
-        def->vcpus = nvcpus;
+        if (virDomainDefSetVcpus(def, nvcpus) < 0)
+            goto cleanup;
         break;
 
     case VIR_DOMAIN_VCPU_LIVE:
@@ -2201,7 +2203,8 @@ libxlDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
                              " with libxenlight"), vm->def->id);
             goto endjob;
         }
-        vm->def->vcpus = nvcpus;
+        if (virDomainDefSetVcpus(vm->def, nvcpus) < 0)
+            goto endjob;
         break;
 
     case VIR_DOMAIN_VCPU_LIVE | VIR_DOMAIN_VCPU_CONFIG:
@@ -2211,8 +2214,9 @@ libxlDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
                              " with libxenlight"), vm->def->id);
             goto endjob;
         }
-        vm->def->vcpus = nvcpus;
-        def->vcpus = nvcpus;
+        if (virDomainDefSetVcpus(vm->def, nvcpus) < 0 ||
+            virDomainDefSetVcpus(def, nvcpus) < 0)
+            goto endjob;
         break;
     }
 
diff --git a/src/lxc/lxc_native.c b/src/lxc/lxc_native.c
index e67a5ad02d..78f9c6789b 100644
--- a/src/lxc/lxc_native.c
+++ b/src/lxc/lxc_native.c
@@ -1024,7 +1024,8 @@ lxcParseConfigString(const char *config,
     if (virDomainDefSetVcpusMax(vmdef, 1) < 0)
         goto error;
 
-    vmdef->vcpus = 1;
+    if (virDomainDefSetVcpus(vmdef, 1) < 0)
+        goto error;
 
     vmdef->nfss = 0;
     vmdef->os.type = VIR_DOMAIN_OSTYPE_EXE;
diff --git a/src/openvz/openvz_conf.c b/src/openvz/openvz_conf.c
index 6629105eb0..e32dd6f3af 100644
--- a/src/openvz/openvz_conf.c
+++ b/src/openvz/openvz_conf.c
@@ -585,7 +585,8 @@ int openvzLoadDomains(struct openvz_driver *driver)
         if (virDomainDefSetVcpusMax(def, vcpus) < 0)
             goto cleanup;
 
-        def->vcpus = vcpus;
+        if (virDomainDefSetVcpus(def, vcpus) < 0)
+            goto cleanup;
 
         /* XXX load rest of VM config data .... */
 
diff --git a/src/openvz/openvz_driver.c b/src/openvz/openvz_driver.c
index 5e55033fde..2a9e6acb90 100644
--- a/src/openvz/openvz_driver.c
+++ b/src/openvz/openvz_driver.c
@@ -1371,7 +1371,9 @@ static int openvzDomainSetVcpusInternal(virDomainObjPtr vm,
     if (virDomainDefSetVcpusMax(vm->def, nvcpus) < 0)
         return -1;
 
-    vm->def->vcpus = nvcpus;
+    if (virDomainDefSetVcpus(vm->def, nvcpus) < 0)
+        return -1;
+
     return 0;
 }
 
diff --git a/src/phyp/phyp_driver.c b/src/phyp/phyp_driver.c
index b60e5ba39d..3d086e3f69 100644
--- a/src/phyp/phyp_driver.c
+++ b/src/phyp/phyp_driver.c
@@ -3298,7 +3298,8 @@ phypDomainGetXMLDesc(virDomainPtr dom, unsigned int flags)
     if (virDomainDefSetVcpusMax(&def, vcpus) < 0)
         goto err;
 
-    def.vcpus = vcpus;
+    if (virDomainDefSetVcpus(&def, vcpus) < 0)
+        goto err;
 
     return virDomainDefFormat(&def,
                               virDomainDefFormatConvertXMLFlags(flags));
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index 837f94578b..c188aa3514 100644
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -12712,6 +12712,7 @@ qemuParseCommandLineSmp(virDomainDefPtr dom,
     unsigned int cores = 0;
     unsigned int threads = 0;
     unsigned int maxcpus = 0;
+    unsigned int vcpus = 0;
     size_t i;
     int nkws;
     char **kws;
@@ -12726,9 +12727,8 @@ qemuParseCommandLineSmp(virDomainDefPtr dom,
     for (i = 0; i < nkws; i++) {
         if (vals[i] == NULL) {
             if (i > 0 ||
-                virStrToLong_i(kws[i], &end, 10, &n) < 0 || *end != '\0')
+                virStrToLong_ui(kws[i], &end, 10, &vcpus) < 0 || *end != '\0')
                 goto syntax;
-            dom->vcpus = n;
         } else {
             if (virStrToLong_i(vals[i], &end, 10, &n) < 0 || *end != '\0')
                 goto syntax;
@@ -12746,11 +12746,14 @@ qemuParseCommandLineSmp(virDomainDefPtr dom,
     }
 
     if (maxcpus == 0)
-        maxcpus = dom->vcpus;
+        maxcpus = vcpus;
 
     if (virDomainDefSetVcpusMax(dom, maxcpus) < 0)
         goto error;
 
+    if (virDomainDefSetVcpus(dom, vcpus) < 0)
+        goto error;
+
     if (sockets && cores && threads) {
         virCPUDefPtr cpu;
 
@@ -12865,7 +12868,8 @@ qemuParseCommandLine(virCapsPtr qemuCaps,
     virDomainDefSetMemoryTotal(def, def->mem.cur_balloon);
     if (virDomainDefSetVcpusMax(def, 1) < 0)
         goto error;
-    def->vcpus = 1;
+    if (virDomainDefSetVcpus(def, 1) < 0)
+        goto error;
     def->clock.offset = VIR_DOMAIN_CLOCK_OFFSET_UTC;
 
     def->onReboot = VIR_DOMAIN_LIFECYCLE_RESTART;
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 6013443071..f07d7a7050 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4835,8 +4835,9 @@ qemuDomainHotplugVcpus(virQEMUDriverPtr driver,
  cleanup:
     VIR_FREE(cpupids);
     VIR_FREE(mem_mask);
-    if (virDomainObjIsActive(vm))
-        vm->def->vcpus = vcpus;
+    if (virDomainObjIsActive(vm) &&
+        virDomainDefSetVcpus(vm->def, vcpus) < 0)
+        ret = -1;
     virDomainAuditVcpu(vm, oldvcpus, nvcpus, "update", rc == 1);
     if (cgroup_vcpu)
         virCgroupFree(&cgroup_vcpu);
@@ -4982,7 +4983,8 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
                 if (virDomainDefSetVcpusMax(persistentDef, nvcpus) < 0)
                     goto endjob;
             } else {
-                persistentDef->vcpus = nvcpus;
+                if (virDomainDefSetVcpus(persistentDef, nvcpus) < 0)
+                    goto endjob;
             }
 
             if (virDomainSaveConfig(cfg->configDir, persistentDef) < 0)
diff --git a/src/test/test_driver.c b/src/test/test_driver.c
index cb6ad7634f..56d8ef22da 100644
--- a/src/test/test_driver.c
+++ b/src/test/test_driver.c
@@ -2375,15 +2375,17 @@ testDomainSetVcpusFlags(virDomainPtr domain, unsigned int nrCpus,
         goto cleanup;
     }
 
-    if (def)
-        def->vcpus = nrCpus;
+    if (def &&
+        virDomainDefSetVcpus(def, nrCpus) < 0)
+        goto cleanup;
 
     if (persistentDef) {
         if (flags & VIR_DOMAIN_VCPU_MAXIMUM) {
             if (virDomainDefSetVcpusMax(persistentDef, nrCpus) < 0)
                 goto cleanup;
         } else {
-            persistentDef->vcpus = nrCpus;
+            if (virDomainDefSetVcpus(persistentDef, nrCpus) < 0)
+                goto cleanup;
         }
     }
 
diff --git a/src/vbox/vbox_common.c b/src/vbox/vbox_common.c
index 61f6476a33..cf4de2db74 100644
--- a/src/vbox/vbox_common.c
+++ b/src/vbox/vbox_common.c
@@ -3910,7 +3910,8 @@ static char *vboxDomainGetXMLDesc(virDomainPtr dom, unsigned int flags)
     if (virDomainDefSetVcpusMax(def, CPUCount) < 0)
         goto cleanup;
 
-    def->vcpus = CPUCount;
+    if (virDomainDefSetVcpus(def, CPUCount) < 0)
+        goto cleanup;
 
     /* Skip cpumasklen, cpumask, onReboot, onPoweroff, onCrash */
 
@@ -6067,7 +6068,8 @@ static char *vboxDomainSnapshotGetXMLDesc(virDomainSnapshotPtr snapshot,
         if (virDomainDefSetVcpusMax(def->dom, CPUCount) < 0)
             goto cleanup;
 
-        def->dom->vcpus = CPUCount;
+        if (virDomainDefSetVcpus(def->dom, CPUCount) < 0)
+            goto cleanup;
 
         if (vboxSnapshotGetReadWriteDisks(def, snapshot) < 0)
             VIR_DEBUG("Could not get read write disks for snapshot");
diff --git a/src/vmx/vmx.c b/src/vmx/vmx.c
index 74b04e2d0b..f948356351 100644
--- a/src/vmx/vmx.c
+++ b/src/vmx/vmx.c
@@ -1461,7 +1461,8 @@ virVMXParseConfig(virVMXContext *ctx,
     if (virDomainDefSetVcpusMax(def, numvcpus) < 0)
         goto cleanup;
 
-    def->vcpus = numvcpus;
+    if (virDomainDefSetVcpus(def, numvcpus) < 0)
+        goto cleanup;
 
     /* vmx:sched.cpu.affinity -> def:cpumask */
     /* NOTE: maps to VirtualMachine:config.cpuAffinity.affinitySet */
diff --git a/src/vz/vz_sdk.c b/src/vz/vz_sdk.c
index 6c61c12700..c26c0bfd0d 100644
--- a/src/vz/vz_sdk.c
+++ b/src/vz/vz_sdk.c
@@ -1153,7 +1153,8 @@ prlsdkConvertCpuInfo(PRL_HANDLE sdkdom,
     if (virDomainDefSetVcpusMax(def, cpuCount) < 0)
         goto cleanup;
 
-    def->vcpus = cpuCount;
+    if (virDomainDefSetVcpus(def, cpuCount) < 0)
+        goto cleanup;
 
     pret = PrlVmCfg_GetCpuMask(sdkdom, NULL, &buflen);
     prlsdkCheckRetGoto(pret, cleanup);
diff --git a/src/xen/xm_internal.c b/src/xen/xm_internal.c
index f9191acb75..83444238c2 100644
--- a/src/xen/xm_internal.c
+++ b/src/xen/xm_internal.c
@@ -708,7 +708,8 @@ xenXMDomainSetVcpusFlags(virConnectPtr conn,
         if (virDomainDefSetVcpusMax(entry->def, vcpus) < 0)
             goto cleanup;
     } else {
-        entry->def->vcpus = vcpus;
+        if (virDomainDefSetVcpus(entry->def, vcpus) < 0)
+            goto cleanup;
     }
 
     /* If this fails, should we try to undo our changes to the
diff --git a/src/xenapi/xenapi_driver.c b/src/xenapi/xenapi_driver.c
index fa66bb19c6..e4e99360f1 100644
--- a/src/xenapi/xenapi_driver.c
+++ b/src/xenapi/xenapi_driver.c
@@ -1505,7 +1505,8 @@ xenapiDomainGetXMLDesc(virDomainPtr dom, unsigned int flags)
     if (virDomainDefSetVcpusMax(defPtr, vcpus) < 0)
         goto error;
 
-    defPtr->vcpus = vcpus;
+    if (virDomainDefSetVcpus(defPtr, vcpus) < 0)
+        goto error;
 
     enum xen_on_normal_exit action;
     if (xen_vm_get_actions_after_shutdown(session, &action, vm))
diff --git a/src/xenconfig/xen_common.c b/src/xenconfig/xen_common.c
index 39c8a795e1..66bd4472f7 100644
--- a/src/xenconfig/xen_common.c
+++ b/src/xenconfig/xen_common.c
@@ -508,7 +508,10 @@ xenParseCPUFeatures(virConfPtr conf, virDomainDefPtr def)
     if (xenConfigGetULong(conf, "vcpu_avail", &count, -1) < 0)
         return -1;
 
-    def->vcpus = MIN(count_one_bits_l(count), virDomainDefGetVcpusMax(def));
+    if (virDomainDefSetVcpus(def, MIN(count_one_bits_l(count),
+                                      virDomainDefGetVcpusMax(def))) < 0)
+        return -1;
+
     if (xenConfigGetString(conf, "cpus", &str, NULL) < 0)
         return -1;
 
diff --git a/src/xenconfig/xen_sxpr.c b/src/xenconfig/xen_sxpr.c
index b251525a1e..484a0949b0 100644
--- a/src/xenconfig/xen_sxpr.c
+++ b/src/xenconfig/xen_sxpr.c
@@ -1092,6 +1092,7 @@ xenParseSxpr(const struct sexpr *root,
     const char *tmp;
     virDomainDefPtr def;
     int hvm = 0, vmlocaltime;
+    unsigned int vcpus;
 
     if (!(def = virDomainDefNew()))
         goto error;
@@ -1175,9 +1176,13 @@ xenParseSxpr(const struct sexpr *root,
 
     if (virDomainDefSetVcpusMax(def, sexpr_int(root, "domain/vcpus")) < 0)
         goto error;
-    def->vcpus = count_one_bits_l(sexpr_u64(root, "domain/vcpu_avail"));
-    if (!def->vcpus || virDomainDefGetVcpusMax(def) < def->vcpus)
-        def->vcpus = virDomainDefGetVcpusMax(def);
+
+    vcpus = count_one_bits_l(sexpr_u64(root, "domain/vcpu_avail"));
+    if (!vcpus || virDomainDefGetVcpusMax(def) < vcpus)
+        vcpus = virDomainDefGetVcpusMax(def);
+
+    if (virDomainDefSetVcpus(def, vcpus) < 0)
+        goto error;
 
     tmp = sexpr_node(root, "domain/on_poweroff");
     if (tmp != NULL) {