qemu: Add support for hot/cold-(un)plug of shmem devices

This is needed in order to migrate a domain with shmem devices as that
is not allowed to migrate.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

src/qemu/qemu_driver.c

@@ -7612,6 +7612,15 @@ qemuDomainAttachDeviceLive(virDomainObjPtr vm,
         dev->data.memory = NULL;
         break;
 
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainAttachShmemDevice(driver, vm,
+                                          dev->data.shmem);
+        if (ret < 0) {
+            alias = dev->data.shmem->info.alias;
+            dev->data.shmem = NULL;
+        }
+        break;
+
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_FS:
     case VIR_DOMAIN_DEVICE_INPUT:
@@ -7623,7 +7632,6 @@ qemuDomainAttachDeviceLive(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_TPM:
     case VIR_DOMAIN_DEVICE_PANIC:
     case VIR_DOMAIN_DEVICE_IOMMU:
@@ -7701,6 +7709,9 @@ qemuDomainDetachDeviceLive(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_MEMORY:
         ret = qemuDomainDetachMemoryDevice(driver, vm, dev->data.memory);
         break;
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainDetachShmemDevice(driver, vm, dev->data.shmem);
+        break;
 
     case VIR_DOMAIN_DEVICE_FS:
     case VIR_DOMAIN_DEVICE_INPUT:
@@ -7712,7 +7723,6 @@ qemuDomainDetachDeviceLive(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_REDIRDEV:
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_TPM:
@@ -7859,6 +7869,7 @@ qemuDomainAttachDeviceConfig(virDomainDefPtr vmdef,
     virDomainControllerDefPtr controller;
     virDomainFSDefPtr fs;
     virDomainRedirdevDefPtr redirdev;
+    virDomainShmemDefPtr shmem;
 
     switch ((virDomainDeviceType) dev->type) {
     case VIR_DOMAIN_DEVICE_DISK:
@@ -7983,6 +7994,18 @@ qemuDomainAttachDeviceConfig(virDomainDefPtr vmdef,
         dev->data.redirdev = NULL;
         break;
 
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        shmem = dev->data.shmem;
+        if (virDomainShmemDefFind(vmdef, shmem) >= 0) {
+            virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                           _("device is already in the domain configuration"));
+            return -1;
+        }
+        if (virDomainShmemDefInsert(vmdef, shmem) < 0)
+            return -1;
+        dev->data.shmem = NULL;
+        break;
+
     case VIR_DOMAIN_DEVICE_INPUT:
     case VIR_DOMAIN_DEVICE_SOUND:
     case VIR_DOMAIN_DEVICE_VIDEO:
@@ -7992,7 +8015,6 @@ qemuDomainAttachDeviceConfig(virDomainDefPtr vmdef,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_TPM:
     case VIR_DOMAIN_DEVICE_PANIC:
@@ -8139,6 +8161,16 @@ qemuDomainDetachDeviceConfig(virDomainDefPtr vmdef,
         virDomainRedirdevDefFree(virDomainRedirdevDefRemove(vmdef, idx));
         break;
 
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        if ((idx = virDomainShmemDefFind(vmdef, dev->data.shmem)) < 0) {
+            virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+                           _("matching shmem device was not found"));
+            return -1;
+        }
+
+        virDomainShmemDefFree(virDomainShmemDefRemove(vmdef, idx));
+        break;
+
 
     case VIR_DOMAIN_DEVICE_INPUT:
     case VIR_DOMAIN_DEVICE_SOUND:
@@ -8149,7 +8181,6 @@ qemuDomainDetachDeviceConfig(virDomainDefPtr vmdef,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_TPM:
     case VIR_DOMAIN_DEVICE_PANIC:

src/qemu/qemu_hotplug.c

@@ -2471,6 +2471,131 @@ qemuDomainAttachHostDevice(virConnectPtr conn,
     return -1;
 }
 
+
+int
+qemuDomainAttachShmemDevice(virQEMUDriverPtr driver,
+                            virDomainObjPtr vm,
+                            virDomainShmemDefPtr shmem)
+{
+    int ret = -1;
+    char *shmstr = NULL;
+    char *charAlias = NULL;
+    char *memAlias = NULL;
+    bool release_backing = false;
+    bool release_address = true;
+    virErrorPtr orig_err = NULL;
+    virJSONValuePtr props = NULL;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+
+    switch ((virDomainShmemModel)shmem->model) {
+    case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_PLAIN:
+    case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_DOORBELL:
+        break;
+
+    case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM:
+        virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
+                       _("live attach of shmem model '%s' is not supported"),
+                       virDomainShmemModelTypeToString(shmem->model));
+        /* fall-through */
+    case VIR_DOMAIN_SHMEM_MODEL_LAST:
+        return -1;
+    }
+
+    if (qemuAssignDeviceShmemAlias(vm->def, shmem, -1) < 0)
+        return -1;
+
+    if (qemuDomainPrepareShmemChardev(shmem) < 0)
+        return -1;
+
+    if (VIR_REALLOC_N(vm->def->shmems, vm->def->nshmems + 1) < 0)
+        return -1;
+
+    if ((shmem->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE ||
+         shmem->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI) &&
+         (virDomainPCIAddressEnsureAddr(priv->pciaddrs, &shmem->info) < 0))
+        return -1;
+
+    if (!(shmstr = qemuBuildShmemDevStr(vm->def, shmem, priv->qemuCaps)))
+        goto cleanup;
+
+    if (shmem->server.enabled) {
+        if (virAsprintf(&charAlias, "char%s", shmem->info.alias) < 0)
+            goto cleanup;
+    } else {
+        if (!(props = qemuBuildShmemBackendMemProps(shmem)))
+            goto cleanup;
+
+        if (virAsprintf(&memAlias, "shmmem-%s", shmem->info.alias) < 0)
+            goto cleanup;
+    }
+
+    qemuDomainObjEnterMonitor(driver, vm);
+
+    if (shmem->server.enabled) {
+        if (qemuMonitorAttachCharDev(priv->mon, charAlias,
+                                     &shmem->server.chr) < 0)
+            goto exit_monitor;
+    } else {
+        if (qemuMonitorAddObject(priv->mon, "memory-backend-file",
+                                 memAlias, props) < 0) {
+            props = NULL;
+            goto exit_monitor;
+        }
+        props = NULL;
+    }
+
+    release_backing = true;
+
+    if (qemuMonitorAddDevice(priv->mon, shmstr) < 0)
+        goto exit_monitor;
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0) {
+        release_address = false;
+        goto cleanup;
+    }
+
+    /* Doing a copy here just so the pointer doesn't get nullified
+     * because we need it in the audit function */
+    VIR_APPEND_ELEMENT_COPY_INPLACE(vm->def->shmems, vm->def->nshmems, shmem);
+
+    ret = 0;
+    release_address = false;
+
+ audit:
+    virDomainAuditShmem(vm, shmem, "attach", ret == 0);
+
+ cleanup:
+    if (release_address)
+        qemuDomainReleaseDeviceAddress(vm, &shmem->info, NULL);
+
+    virJSONValueFree(props);
+    VIR_FREE(memAlias);
+    VIR_FREE(charAlias);
+    VIR_FREE(shmstr);
+
+    return ret;
+
+ exit_monitor:
+    orig_err = virSaveLastError();
+    if (release_backing) {
+        if (shmem->server.enabled)
+            ignore_value(qemuMonitorDetachCharDev(priv->mon, charAlias));
+        else
+            ignore_value(qemuMonitorDelObject(priv->mon, memAlias));
+    }
+
+    if (orig_err) {
+        virSetError(orig_err);
+        virFreeError(orig_err);
+    }
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        release_address = false;
+
+    goto audit;
+}
+
+
 static int
 qemuDomainChangeNetBridge(virDomainObjPtr vm,
                           virDomainNetDefPtr olddev,
@@ -3787,6 +3912,62 @@ qemuDomainRemoveRNGDevice(virQEMUDriverPtr driver,
 }
 
 
+static int
+qemuDomainRemoveShmemDevice(virQEMUDriverPtr driver,
+                            virDomainObjPtr vm,
+                            virDomainShmemDefPtr shmem)
+{
+    int rc;
+    int ret = -1;
+    ssize_t idx = -1;
+    char *charAlias = NULL;
+    char *memAlias = NULL;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+    virObjectEventPtr event = NULL;
+
+    VIR_DEBUG("Removing shmem device %s from domain %p %s",
+              shmem->info.alias, vm, vm->def->name);
+
+    if (shmem->server.enabled) {
+        if (virAsprintf(&charAlias, "char%s", shmem->info.alias) < 0)
+            return -1;
+    } else {
+        if (virAsprintf(&memAlias, "shmmem-%s", shmem->info.alias) < 0)
+            return -1;
+    }
+
+    qemuDomainObjEnterMonitor(driver, vm);
+
+    if (shmem->server.enabled)
+        rc = qemuMonitorDetachCharDev(priv->mon, charAlias);
+    else
+        rc = qemuMonitorDelObject(priv->mon, memAlias);
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
+
+    virDomainAuditShmem(vm, shmem, "detach", rc == 0);
+
+    if (rc < 0)
+        goto cleanup;
+
+    event = virDomainEventDeviceRemovedNewFromObj(vm, shmem->info.alias);
+    qemuDomainEventQueue(driver, event);
+
+    if ((idx = virDomainShmemDefFind(vm->def, shmem)) >= 0)
+        virDomainShmemDefRemove(vm->def, idx);
+    qemuDomainReleaseDeviceAddress(vm, &shmem->info, NULL);
+    virDomainShmemDefFree(shmem);
+
+    ret = 0;
+ cleanup:
+    VIR_FREE(charAlias);
+    VIR_FREE(memAlias);
+
+    return ret;
+}
+
+
 int
 qemuDomainRemoveDevice(virQEMUDriverPtr driver,
                        virDomainObjPtr vm,
@@ -3818,6 +3999,10 @@ qemuDomainRemoveDevice(virQEMUDriverPtr driver,
         ret = qemuDomainRemoveMemoryDevice(driver, vm, dev->data.memory);
         break;
 
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainRemoveShmemDevice(driver, vm, dev->data.shmem);
+        break;
+
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_LEASE:
     case VIR_DOMAIN_DEVICE_FS:
@@ -3831,7 +4016,6 @@ qemuDomainRemoveDevice(virQEMUDriverPtr driver,
     case VIR_DOMAIN_DEVICE_SMARTCARD:
     case VIR_DOMAIN_DEVICE_MEMBALLOON:
     case VIR_DOMAIN_DEVICE_NVRAM:
-    case VIR_DOMAIN_DEVICE_SHMEM:
     case VIR_DOMAIN_DEVICE_TPM:
     case VIR_DOMAIN_DEVICE_PANIC:
     case VIR_DOMAIN_DEVICE_IOMMU:
@@ -4406,6 +4590,59 @@ int qemuDomainDetachHostDevice(virQEMUDriverPtr driver,
         return qemuDomainDetachThisHostDevice(driver, vm, detach);
 }
 
+
+int
+qemuDomainDetachShmemDevice(virQEMUDriverPtr driver,
+                            virDomainObjPtr vm,
+                            virDomainShmemDefPtr dev)
+{
+    int ret = -1;
+    ssize_t idx = -1;
+    virDomainShmemDefPtr shmem = NULL;
+    qemuDomainObjPrivatePtr priv = vm->privateData;
+
+    if ((idx = virDomainShmemDefFind(vm->def, dev)) < 0) {
+        virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+                       _("device not present in domain configuration"));
+        return -1;
+    }
+
+    shmem = vm->def->shmems[idx];
+
+    switch ((virDomainShmemModel)shmem->model) {
+    case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_PLAIN:
+    case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM_DOORBELL:
+        break;
+
+    case VIR_DOMAIN_SHMEM_MODEL_IVSHMEM:
+        virReportError(VIR_ERR_OPERATION_UNSUPPORTED,
+                       _("live detach of shmem model '%s' is not supported"),
+                       virDomainShmemModelTypeToString(shmem->model));
+        /* fall-through */
+    case VIR_DOMAIN_SHMEM_MODEL_LAST:
+        return -1;
+    }
+
+    qemuDomainMarkDeviceForRemoval(vm, &shmem->info);
+    qemuDomainObjEnterMonitor(driver, vm);
+
+    ret = qemuMonitorDelDevice(priv->mon, shmem->info.alias);
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
+
+    if (ret == 0) {
+        if ((ret = qemuDomainWaitForDeviceRemoval(vm)) == 1) {
+            qemuDomainReleaseDeviceAddress(vm, &shmem->info, NULL);
+            ret = qemuDomainRemoveShmemDevice(driver, vm, shmem);
+        }
+    }
+    qemuDomainResetDeviceRemoval(vm);
+
+    return ret;
+}
+
+
 int
 qemuDomainDetachNetDevice(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,

src/qemu/qemu_hotplug.h

@@ -51,6 +51,9 @@ int qemuDomainAttachHostDevice(virConnectPtr conn,
                                virQEMUDriverPtr driver,
                                virDomainObjPtr vm,
                                virDomainHostdevDefPtr hostdev);
+int qemuDomainAttachShmemDevice(virQEMUDriverPtr driver,
+                                virDomainObjPtr vm,
+                                virDomainShmemDefPtr shmem);
 int qemuDomainFindGraphicsIndex(virDomainDefPtr def,
                                 virDomainGraphicsDefPtr dev);
 int qemuDomainAttachMemory(virQEMUDriverPtr driver,
@@ -87,6 +90,9 @@ int qemuDomainDetachNetDevice(virQEMUDriverPtr driver,
 int qemuDomainDetachHostDevice(virQEMUDriverPtr driver,
                                virDomainObjPtr vm,
                                virDomainDeviceDefPtr dev);
+int qemuDomainDetachShmemDevice(virQEMUDriverPtr driver,
+                                virDomainObjPtr vm,
+                                virDomainShmemDefPtr dev);
 int qemuDomainAttachLease(virQEMUDriverPtr driver,
                           virDomainObjPtr vm,
                           virDomainLeaseDefPtr lease);

tests/qemuhotplugtest.c

@@ -74,6 +74,8 @@ qemuHotplugCreateObjects(virDomainXMLOptionPtr xmlopt,
     virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_VIRTIO_SCSI);
     virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_DEVICE_USB_STORAGE);
     virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_VIRTIO_CCW);
+    virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_DEVICE_IVSHMEM_PLAIN);
+    virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_DEVICE_IVSHMEM_DOORBELL);
     if (event)
         virQEMUCapsSet(priv->qemuCaps, QEMU_CAPS_DEVICE_DEL_EVENT);
 
@@ -120,6 +122,9 @@ testQemuHotplugAttach(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_CHR:
         ret = qemuDomainAttachChrDevice(NULL, &driver, vm, dev->data.chr);
         break;
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainAttachShmemDevice(&driver, vm, dev->data.shmem);
+        break;
     default:
         VIR_TEST_VERBOSE("device type '%s' cannot be attached\n",
                 virDomainDeviceTypeToString(dev->type));
@@ -142,6 +147,9 @@ testQemuHotplugDetach(virDomainObjPtr vm,
     case VIR_DOMAIN_DEVICE_CHR:
         ret = qemuDomainDetachChrDevice(&driver, vm, dev->data.chr);
         break;
+    case VIR_DOMAIN_DEVICE_SHMEM:
+        ret = qemuDomainDetachShmemDevice(&driver, vm, dev->data.shmem);
+        break;
     default:
         VIR_TEST_VERBOSE("device type '%s' cannot be detached\n",
                 virDomainDeviceTypeToString(dev->type));
@@ -561,6 +569,19 @@ mymain(void)
                    "human-monitor-command", HMP("OK\\r\\n"),
                    "device_add", QMP_OK);
 
+    DO_TEST_ATTACH("base-live", "ivshmem-plain", false, true,
+                   "object-add", QMP_OK,
+                   "device_add", QMP_OK);
+    DO_TEST_ATTACH("base-live", "ivshmem-doorbell", false, true,
+                   "chardev-add", QMP_OK,
+                   "device_add", QMP_OK);
+    DO_TEST_DETACH("base-live+ivshmem-plain", "ivshmem-doorbell-detach", false, true,
+                   "device_del", QMP_OK,
+                   "chardev-remove", QMP_OK);
+    DO_TEST_DETACH("base-live", "ivshmem-plain-detach", false, false,
+                   "device_del", QMP_OK,
+                   "object-del", QMP_OK);
+
     qemuTestDriverFree(&driver);
     return (ret == 0) ? EXIT_SUCCESS : EXIT_FAILURE;
 }

tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-doorbell-detach.xml

+<shmem name='shmem1'>
+  <model type='ivshmem-doorbell'/>
+  <server path='/var/lib/libvirt/shmem-shmem1-sock'/>
+  <msi ioeventfd='on'/>
+  <alias name='shmem1'/>
+  <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
+</shmem>

tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-doorbell.xml

+<shmem name='shmem1'>
+  <model type='ivshmem-doorbell'/>
+  <server/>
+</shmem>

tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-plain-detach.xml

+<shmem name='shmem0'>
+  <model type='ivshmem-plain'/>
+  <size unit='M'>4</size>
+  <alias name='shmem0'/>
+  <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
+</shmem>

tests/qemuhotplugtestdevices/qemuhotplug-ivshmem-plain.xml

+<shmem name='shmem0'>
+  <model type='ivshmem-plain'/>
+</shmem>

tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-doorbell-detach.xml

+qemuhotplug-base-live+ivshmem-plain.xml
\ No newline at end of file

tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-doorbell.xml

+<domain type='kvm' id='7'>
+  <name>hotplug</name>
+  <uuid>d091ea82-29e6-2e34-3005-f02617b36e87</uuid>
+  <memory unit='KiB'>4194304</memory>
+  <currentMemory unit='KiB'>4194304</currentMemory>
+  <vcpu placement='static'>4</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <devices>
+    <emulator>/usr/libexec/qemu-kvm</emulator>
+    <controller type='usb' index='0'>
+      <alias name='usb'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+    </controller>
+    <controller type='ide' index='0'>
+      <alias name='ide'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+    </controller>
+    <controller type='scsi' index='0' model='virtio-scsi'>
+      <alias name='scsi0'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'>
+      <alias name='pci'/>
+    </controller>
+    <controller type='virtio-serial' index='0'>
+      <alias name='virtio-serial0'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
+    </controller>
+    <input type='mouse' bus='ps2'>
+      <alias name='input0'/>
+    </input>
+    <input type='keyboard' bus='ps2'>
+      <alias name='input1'/>
+    </input>
+    <memballoon model='none'>
+      <alias name='balloon0'/>
+    </memballoon>
+    <shmem name='shmem0'>
+      <model type='ivshmem-plain'/>
+      <size unit='M'>4</size>
+      <alias name='shmem0'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
+    </shmem>
+    <shmem name='shmem1'>
+      <model type='ivshmem-doorbell'/>
+      <server path='/var/lib/libvirt/shmem-shmem1-sock'/>
+      <msi ioeventfd='on'/>
+      <alias name='shmem1'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
+    </shmem>
+  </devices>
+  <seclabel type='none' model='none'/>
+</domain>

tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-plain-detach.xml

+qemuhotplug-base-live.xml
\ No newline at end of file

tests/qemuhotplugtestdomains/qemuhotplug-base-live+ivshmem-plain.xml

+<domain type='kvm' id='7'>
+  <name>hotplug</name>
+  <uuid>d091ea82-29e6-2e34-3005-f02617b36e87</uuid>
+  <memory unit='KiB'>4194304</memory>
+  <currentMemory unit='KiB'>4194304</currentMemory>
+  <vcpu placement='static'>4</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc'>hvm</type>
+    <boot dev='hd'/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>restart</on_reboot>
+  <on_crash>restart</on_crash>
+  <devices>
+    <emulator>/usr/libexec/qemu-kvm</emulator>
+    <controller type='usb' index='0'>
+      <alias name='usb'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+    </controller>
+    <controller type='ide' index='0'>
+      <alias name='ide'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+    </controller>
+    <controller type='scsi' index='0' model='virtio-scsi'>
+      <alias name='scsi0'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
+    </controller>
+    <controller type='pci' index='0' model='pci-root'>
+      <alias name='pci'/>
+    </controller>
+    <controller type='virtio-serial' index='0'>
+      <alias name='virtio-serial0'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
+    </controller>
+    <input type='mouse' bus='ps2'>
+      <alias name='input0'/>
+    </input>
+    <input type='keyboard' bus='ps2'>
+      <alias name='input1'/>
+    </input>
+    <memballoon model='none'>
+      <alias name='balloon0'/>
+    </memballoon>
+    <shmem name='shmem0'>
+      <model type='ivshmem-plain'/>
+      <size unit='M'>4</size>
+      <alias name='shmem0'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
+    </shmem>
+  </devices>
+  <seclabel type='none' model='none'/>
+</domain>