Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pc, pci: features, fixes, cleanups

virtio-pmem support.
libvhost user mq support.
A bunch of fixes all over the place.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Thu 04 Jul 2019 22:00:49 BST
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (22 commits)
  docs: avoid vhost-user-net specifics in multiqueue section
  libvhost-user: implement VHOST_USER_PROTOCOL_F_MQ
  libvhost-user: support many virtqueues
  libvhost-user: add vmsg_set_reply_u64() helper
  pc: Move compat_apic_id_mode variable to PCMachineClass
  virtio: Don't change "started" flag on virtio_vmstate_change()
  virtio: Make sure we get correct state of device on handle_aio_output()
  virtio: Set "start_on_kick" on virtio_set_features()
  virtio: Set "start_on_kick" for legacy devices
  virtio: add "use-started" property
  virtio-pci: fix missing device properties
  pc: Support for virtio-pmem-pci
  numa: Handle virtio-pmem in NUMA stats
  hmp: Handle virtio-pmem when printing memory device infos
  virtio-pci: Proxy for virtio-pmem
  virtio-pmem: sync linux headers
  virtio-pci: Allow to specify additional interfaces for the base type
  virtio-pmem: add virtio device
  pcie: minor cleanups for slot control/status
  pcie: work around for racy guest init
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

17 files changed, 556 insertions, 70 deletions

diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 9cb6133..85bc401 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -191,7 +191,7 @@ static void vhost_user_blk_stop(VirtIODevice *vdev)
 static void vhost_user_blk_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostUserBlk *s = VHOST_USER_BLK(vdev);
-    bool should_start = vdev->started;
+    bool should_start = virtio_device_started(vdev, status);
     int ret;
 
     if (!vdev->vm_running) {
@@ -317,7 +317,7 @@ static int vhost_user_blk_connect(DeviceState *dev)
     }
 
     /* restore vhost state */
-    if (vdev->started) {
+    if (virtio_device_started(vdev, vdev->status)) {
         ret = vhost_user_blk_start(vdev);
         if (ret < 0) {
             error_report("vhost-user-blk: vhost start failed: %s",
diff --git a/hw/core/machine.c b/hw/core/machine.c
index ea5a01a..ea84bd6 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -30,6 +30,7 @@ GlobalProperty hw_compat_4_0[] = {
     { "bochs-display",  "edid", "false" },
     { "virtio-vga",     "edid", "false" },
     { "virtio-gpu-pci", "edid", "false" },
+    { "virtio-device", "use-started", "false" },
 };
 const size_t hw_compat_4_0_len = G_N_ELEMENTS(hw_compat_4_0);
 
diff --git a/hw/core/numa.c b/hw/core/numa.c
index 76c447f..66119d1 100644
--- a/hw/core/numa.c
+++ b/hw/core/numa.c
@@ -533,6 +533,7 @@ static void numa_stat_memory_devices(NumaNodeMem node_mem[])
     MemoryDeviceInfoList *info_list = qmp_memory_device_list();
     MemoryDeviceInfoList *info;
     PCDIMMDeviceInfo     *pcdimm_info;
+    VirtioPMEMDeviceInfo *vpi;
 
     for (info = info_list; info; info = info->next) {
         MemoryDeviceInfo *value = info->value;
@@ -540,22 +541,21 @@ static void numa_stat_memory_devices(NumaNodeMem node_mem[])
         if (value) {
             switch (value->type) {
             case MEMORY_DEVICE_INFO_KIND_DIMM:
-                pcdimm_info = value->u.dimm.data;
-                break;
-
             case MEMORY_DEVICE_INFO_KIND_NVDIMM:
-                pcdimm_info = value->u.nvdimm.data;
-                break;
-
-            default:
-                pcdimm_info = NULL;
-                break;
-            }
-
-            if (pcdimm_info) {
+                pcdimm_info = value->type == MEMORY_DEVICE_INFO_KIND_DIMM ?
+                              value->u.dimm.data : value->u.nvdimm.data;
                 node_mem[pcdimm_info->node].node_mem += pcdimm_info->size;
                 node_mem[pcdimm_info->node].node_plugged_mem +=
                     pcdimm_info->size;
+                break;
+            case MEMORY_DEVICE_INFO_KIND_VIRTIO_PMEM:
+                vpi = value->u.virtio_pmem.data;
+                /* TODO: once we support numa, assign to right node */
+                node_mem[0].node_mem += vpi->size;
+                node_mem[0].node_plugged_mem += vpi->size;
+                break;
+            default:
+                g_assert_not_reached();
             }
         }
     }
diff --git a/hw/i386/Kconfig b/hw/i386/Kconfig
index 9817888..4ddf2a9 100644
--- a/hw/i386/Kconfig
+++ b/hw/i386/Kconfig
@@ -30,6 +30,7 @@ config PC
     # For ACPI builder:
     select SERIAL_ISA
     select ACPI_VMGENID
+    select VIRTIO_PMEM_SUPPORTED
 
 config PC_PCI
     bool
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index e96360b..b380bd7 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -79,6 +79,8 @@
 #include "hw/i386/intel_iommu.h"
 #include "hw/net/ne2000-isa.h"
 #include "standard-headers/asm-x86/bootparam.h"
+#include "hw/virtio/virtio-pmem-pci.h"
+#include "hw/mem/memory-device.h"
 
 /* debug PC/ISA interrupts */
 //#define DEBUG_IRQ
@@ -913,14 +915,6 @@ bool e820_get_entry(int idx, uint32_t type, uint64_t *address, uint64_t *length)
     return false;
 }
 
-/* Enables contiguous-apic-ID mode, for compatibility */
-static bool compat_apic_id_mode;
-
-void enable_compat_apic_id_mode(void)
-{
-    compat_apic_id_mode = true;
-}
-
 /* Calculates initial APIC ID for a specific CPU index
  *
  * Currently we need to be able to calculate the APIC ID from the CPU index
@@ -928,13 +922,15 @@ void enable_compat_apic_id_mode(void)
  * no concept of "CPU index", and the NUMA tables on fw_cfg need the APIC ID of
  * all CPUs up to max_cpus.
  */
-static uint32_t x86_cpu_apic_id_from_index(unsigned int cpu_index)
+static uint32_t x86_cpu_apic_id_from_index(PCMachineState *pcms,
+                                           unsigned int cpu_index)
 {
+    PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
     uint32_t correct_id;
     static bool warned;
 
     correct_id = x86_apicid_from_cpu_idx(smp_cores, smp_threads, cpu_index);
-    if (compat_apic_id_mode) {
+    if (pcmc->compat_apic_id_mode) {
         if (cpu_index != correct_id && !warned && !qtest_enabled()) {
             error_report("APIC IDs set in compatibility mode, "
                          "CPU topology won't match the configuration");
@@ -1533,7 +1529,8 @@ static void pc_new_cpu(const char *typename, int64_t apic_id, Error **errp)
 void pc_hot_add_cpu(const int64_t id, Error **errp)
 {
     MachineState *ms = MACHINE(qdev_get_machine());
-    int64_t apic_id = x86_cpu_apic_id_from_index(id);
+    PCMachineState *pcms = PC_MACHINE(ms);
+    int64_t apic_id = x86_cpu_apic_id_from_index(pcms, id);
     Error *local_err = NULL;
 
     if (id < 0) {
@@ -1569,7 +1566,7 @@ void pc_cpus_init(PCMachineState *pcms)
      *
      * This is used for FW_CFG_MAX_CPUS. See comments on bochs_bios_init().
      */
-    pcms->apic_id_limit = x86_cpu_apic_id_from_index(max_cpus - 1) + 1;
+    pcms->apic_id_limit = x86_cpu_apic_id_from_index(pcms, max_cpus - 1) + 1;
     possible_cpus = mc->possible_cpu_arch_ids(ms);
     for (i = 0; i < smp_cpus; i++) {
         pc_new_cpu(possible_cpus->cpus[i].type, possible_cpus->cpus[i].arch_id,
@@ -2395,6 +2392,65 @@ static void pc_cpu_pre_plug(HotplugHandler *hotplug_dev,
     numa_cpu_pre_plug(cpu_slot, dev, errp);
 }
 
+static void pc_virtio_pmem_pci_pre_plug(HotplugHandler *hotplug_dev,
+                                        DeviceState *dev, Error **errp)
+{
+    HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
+    Error *local_err = NULL;
+
+    if (!hotplug_dev2) {
+        /*
+         * Without a bus hotplug handler, we cannot control the plug/unplug
+         * order. This should never be the case on x86, however better add
+         * a safety net.
+         */
+        error_setg(errp, "virtio-pmem-pci not supported on this bus.");
+        return;
+    }
+    /*
+     * First, see if we can plug this memory device at all. If that
+     * succeeds, branch of to the actual hotplug handler.
+     */
+    memory_device_pre_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev), NULL,
+                           &local_err);
+    if (!local_err) {
+        hotplug_handler_pre_plug(hotplug_dev2, dev, &local_err);
+    }
+    error_propagate(errp, local_err);
+}
+
+static void pc_virtio_pmem_pci_plug(HotplugHandler *hotplug_dev,
+                                    DeviceState *dev, Error **errp)
+{
+    HotplugHandler *hotplug_dev2 = qdev_get_bus_hotplug_handler(dev);
+    Error *local_err = NULL;
+
+    /*
+     * Plug the memory device first and then branch off to the actual
+     * hotplug handler. If that one fails, we can easily undo the memory
+     * device bits.
+     */
+    memory_device_plug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
+    hotplug_handler_plug(hotplug_dev2, dev, &local_err);
+    if (local_err) {
+        memory_device_unplug(MEMORY_DEVICE(dev), MACHINE(hotplug_dev));
+    }
+    error_propagate(errp, local_err);
+}
+
+static void pc_virtio_pmem_pci_unplug_request(HotplugHandler *hotplug_dev,
+                                              DeviceState *dev, Error **errp)
+{
+    /* We don't support virtio pmem hot unplug */
+    error_setg(errp, "virtio pmem device unplug not supported.");
+}
+
+static void pc_virtio_pmem_pci_unplug(HotplugHandler *hotplug_dev,
+                                      DeviceState *dev, Error **errp)
+{
+    /* We don't support virtio pmem hot unplug */
+}
+
 static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
                                           DeviceState *dev, Error **errp)
 {
@@ -2402,6 +2458,8 @@ static void pc_machine_device_pre_plug_cb(HotplugHandler *hotplug_dev,
         pc_memory_pre_plug(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_pre_plug(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI)) {
+        pc_virtio_pmem_pci_pre_plug(hotplug_dev, dev, errp);
     }
 }
 
@@ -2412,6 +2470,8 @@ static void pc_machine_device_plug_cb(HotplugHandler *hotplug_dev,
         pc_memory_plug(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_plug(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI)) {
+        pc_virtio_pmem_pci_plug(hotplug_dev, dev, errp);
     }
 }
 
@@ -2422,6 +2482,8 @@ static void pc_machine_device_unplug_request_cb(HotplugHandler *hotplug_dev,
         pc_memory_unplug_request(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_unplug_request_cb(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI)) {
+        pc_virtio_pmem_pci_unplug_request(hotplug_dev, dev, errp);
     } else {
         error_setg(errp, "acpi: device unplug request for not supported device"
                    " type: %s", object_get_typename(OBJECT(dev)));
@@ -2435,6 +2497,8 @@ static void pc_machine_device_unplug_cb(HotplugHandler *hotplug_dev,
         pc_memory_unplug(hotplug_dev, dev, errp);
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
         pc_cpu_unplug_cb(hotplug_dev, dev, errp);
+    } else if (object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI)) {
+        pc_virtio_pmem_pci_unplug(hotplug_dev, dev, errp);
     } else {
         error_setg(errp, "acpi: device unplug for not supported device"
                    " type: %s", object_get_typename(OBJECT(dev)));
@@ -2445,7 +2509,8 @@ static HotplugHandler *pc_get_hotplug_handler(MachineState *machine,
                                              DeviceState *dev)
 {
     if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM) ||
-        object_dynamic_cast(OBJECT(dev), TYPE_CPU)) {
+        object_dynamic_cast(OBJECT(dev), TYPE_CPU) ||
+        object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_PMEM_PCI)) {
         return HOTPLUG_HANDLER(machine);
     }
 
@@ -2660,6 +2725,7 @@ static int64_t pc_get_default_cpu_node_id(const MachineState *ms, int idx)
 
 static const CPUArchIdList *pc_possible_cpu_arch_ids(MachineState *ms)
 {
+    PCMachineState *pcms = PC_MACHINE(ms);
     int i;
 
     if (ms->possible_cpus) {
@@ -2679,7 +2745,7 @@ static const CPUArchIdList *pc_possible_cpu_arch_ids(MachineState *ms)
 
         ms->possible_cpus->cpus[i].type = ms->cpu_type;
         ms->possible_cpus->cpus[i].vcpus_count = 1;
-        ms->possible_cpus->cpus[i].arch_id = x86_cpu_apic_id_from_index(i);
+        ms->possible_cpus->cpus[i].arch_id = x86_cpu_apic_id_from_index(pcms, i);
         x86_topo_ids_from_apicid(ms->possible_cpus->cpus[i].arch_id,
                                  smp_cores, smp_threads, &topo);
         ms->possible_cpus->cpus[i].props.has_socket_id = true;
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index c07c4a5..f29de58 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -358,7 +358,6 @@ static void pc_compat_1_4_fn(MachineState *machine)
 static void pc_compat_1_3(MachineState *machine)
 {
     pc_compat_1_4_fn(machine);
-    enable_compat_apic_id_mode();
 }
 
 /* PC compat function for pc-0.14 to pc-1.2 */
@@ -708,6 +707,7 @@ DEFINE_I440FX_MACHINE(v1_4, "pc-i440fx-1.4", pc_compat_1_4_fn,
 
 static void pc_i440fx_1_3_machine_options(MachineClass *m)
 {
+    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
     static GlobalProperty compat[] = {
         PC_CPU_MODEL_IDS("1.3.0")
         { "usb-tablet", "usb_version", "1" },
@@ -718,6 +718,7 @@ static void pc_i440fx_1_3_machine_options(MachineClass *m)
 
     pc_i440fx_1_4_machine_options(m);
     m->hw_version = "1.3.0";
+    pcmc->compat_apic_id_mode = true;
     compat_props_add(m->compat_props, compat, G_N_ELEMENTS(compat));
 }
 
diff --git a/hw/pci-bridge/pcie_root_port.c b/hw/pci-bridge/pcie_root_port.c
index 92f253c..09019ca 100644
--- a/hw/pci-bridge/pcie_root_port.c
+++ b/hw/pci-bridge/pcie_root_port.c
@@ -31,10 +31,13 @@ static void rp_write_config(PCIDevice *d, uint32_t address,
 {
     uint32_t root_cmd =
         pci_get_long(d->config + d->exp.aer_cap + PCI_ERR_ROOT_COMMAND);
+    uint16_t slt_ctl, slt_sta;
+
+    pcie_cap_slot_get(d, &slt_ctl, &slt_sta);
 
     pci_bridge_write_config(d, address, val, len);
     rp_aer_vector_update(d);
-    pcie_cap_slot_write_config(d, address, val, len);
+    pcie_cap_slot_write_config(d, slt_ctl, slt_sta, address, val, len);
     pcie_aer_write_config(d, address, val, len);
     pcie_aer_root_write_config(d, address, val, len, root_cmd);
 }
diff --git a/hw/pci-bridge/xio3130_downstream.c b/hw/pci-bridge/xio3130_downstream.c
index 264e37d..899b0fd 100644
--- a/hw/pci-bridge/xio3130_downstream.c
+++ b/hw/pci-bridge/xio3130_downstream.c
@@ -41,9 +41,12 @@
 static void xio3130_downstream_write_config(PCIDevice *d, uint32_t address,
                                          uint32_t val, int len)
 {
+    uint16_t slt_ctl, slt_sta;
+
+    pcie_cap_slot_get(d, &slt_sta, &slt_ctl);
     pci_bridge_write_config(d, address, val, len);
     pcie_cap_flr_write_config(d, address, val, len);
-    pcie_cap_slot_write_config(d, address, val, len);
+    pcie_cap_slot_write_config(d, slt_ctl, slt_sta, address, val, len);
     pcie_aer_write_config(d, address, val, len);
 }
 
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index 88c30ff..a6beb56 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -383,7 +383,7 @@ static void pcie_cap_slot_event(PCIDevice *dev, PCIExpressHotPlugEvent event)
 {
     /* Minor optimization: if nothing changed - no event is needed. */
     if (pci_word_test_and_set_mask(dev->config + dev->exp.exp_cap +
-                                   PCI_EXP_SLTSTA, event)) {
+                                   PCI_EXP_SLTSTA, event) == event) {
         return;
     }
     hotplug_event_notify(dev);
@@ -594,7 +594,16 @@ void pcie_cap_slot_reset(PCIDevice *dev)
     hotplug_event_update_event_status(dev);
 }
 
+void pcie_cap_slot_get(PCIDevice *dev, uint16_t *slt_ctl, uint16_t *slt_sta)
+{
+    uint32_t pos = dev->exp.exp_cap;
+    uint8_t *exp_cap = dev->config + pos;
+    *slt_ctl = pci_get_word(exp_cap + PCI_EXP_SLTCTL);
+    *slt_sta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
+}
+
 void pcie_cap_slot_write_config(PCIDevice *dev,
+                                uint16_t old_slt_ctl, uint16_t old_slt_sta,
                                 uint32_t addr, uint32_t val, int len)
 {
     uint32_t pos = dev->exp.exp_cap;
@@ -602,6 +611,25 @@ void pcie_cap_slot_write_config(PCIDevice *dev,
     uint16_t sltsta = pci_get_word(exp_cap + PCI_EXP_SLTSTA);
 
     if (ranges_overlap(addr, len, pos + PCI_EXP_SLTSTA, 2)) {
+        /*
+         * Guests tend to clears all bits during init.
+         * If they clear bits that weren't set this is racy and will lose events:
+         * not a big problem for manual button presses, but a problem for us.
+         * As a work-around, detect this and revert status to what it was
+         * before the write.
+         *
+         * Note: in theory this can be detected as a duplicate button press
+         * which cancels the previous press. Does not seem to happen in
+         * practice as guests seem to only have this bug during init.
+         */
+#define PCIE_SLOT_EVENTS (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD | \
+                          PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC | \
+                          PCI_EXP_SLTSTA_CC)
+
+        if (val & ~old_slt_sta & PCIE_SLOT_EVENTS) {
+            sltsta = (sltsta & ~PCIE_SLOT_EVENTS) | (old_slt_sta & PCIE_SLOT_EVENTS);
+            pci_set_word(exp_cap + PCI_EXP_SLTSTA, sltsta);
+        }
         hotplug_event_clear(dev);
     }
 
@@ -619,11 +647,17 @@ void pcie_cap_slot_write_config(PCIDevice *dev,
     }
 
     /*
-     * If the slot is polulated, power indicator is off and power
+     * If the slot is populated, power indicator is off and power
      * controller is off, it is safe to detach the devices.
+     *
+     * Note: don't detach if condition was already true:
+     * this is a work around for guests that overwrite
+     * control of powered off slots before powering them on.
      */
     if ((sltsta & PCI_EXP_SLTSTA_PDS) && (val & PCI_EXP_SLTCTL_PCC) &&
-        ((val & PCI_EXP_SLTCTL_PIC_OFF) == PCI_EXP_SLTCTL_PIC_OFF)) {
+        (val & PCI_EXP_SLTCTL_PIC_OFF) == PCI_EXP_SLTCTL_PIC_OFF &&
+        (!(old_slt_ctl & PCI_EXP_SLTCTL_PCC) ||
+        (old_slt_ctl & PCI_EXP_SLTCTL_PIC_OFF) != PCI_EXP_SLTCTL_PIC_OFF)) {
         PCIBus *sec_bus = pci_bridge_get_sec_bus(PCI_BRIDGE(dev));
         pci_for_each_device(sec_bus, pci_bus_num(sec_bus),
                             pcie_unplug_device, NULL);
diff --git a/hw/virtio/Kconfig b/hw/virtio/Kconfig
index e0452de..3724ff8 100644
--- a/hw/virtio/Kconfig
+++ b/hw/virtio/Kconfig
@@ -29,3 +29,13 @@ config VIRTIO_CRYPTO
     bool
     default y
     depends on VIRTIO
+
+config VIRTIO_PMEM_SUPPORTED
+    bool
+
+config VIRTIO_PMEM
+    bool
+    default y
+    depends on VIRTIO
+    depends on VIRTIO_PMEM_SUPPORTED
+    select MEM_DEVICE
diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index 5570ea8..964ce78 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -12,6 +12,8 @@ common-obj-$(CONFIG_VIRTIO_MMIO) += virtio-mmio.o
 obj-$(CONFIG_VIRTIO_BALLOON) += virtio-balloon.o
 obj-$(CONFIG_VIRTIO_CRYPTO) += virtio-crypto.o
 obj-$(call land,$(CONFIG_VIRTIO_CRYPTO),$(CONFIG_VIRTIO_PCI)) += virtio-crypto-pci.o
+obj-$(CONFIG_VIRTIO_PMEM) += virtio-pmem.o
+common-obj-$(call land,$(CONFIG_VIRTIO_PMEM),$(CONFIG_VIRTIO_PCI)) += virtio-pmem-pci.o
 obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock.o
 
 ifeq ($(CONFIG_VIRTIO_PCI),y)
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index e6d5467..ce928f2 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1913,13 +1913,6 @@ static void virtio_pci_generic_class_init(ObjectClass *klass, void *data)
     dc->props = virtio_pci_generic_properties;
 }
 
-/* Used when the generic type and the base type is the same */
-static void virtio_pci_generic_base_class_init(ObjectClass *klass, void *data)
-{
-    virtio_pci_base_class_init(klass, data);
-    virtio_pci_generic_class_init(klass, NULL);
-}
-
 static void virtio_pci_transitional_instance_init(Object *obj)
 {
     VirtIOPCIProxy *proxy = VIRTIO_PCI(obj);
@@ -1938,15 +1931,15 @@ static void virtio_pci_non_transitional_instance_init(Object *obj)
 
 void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t)
 {
+    char *base_name = NULL;
     TypeInfo base_type_info = {
         .name          = t->base_name,
         .parent        = t->parent ? t->parent : TYPE_VIRTIO_PCI,
         .instance_size = t->instance_size,
         .instance_init = t->instance_init,
         .class_size    = t->class_size,
-        .class_init    = virtio_pci_base_class_init,
-        .class_data    = (void *)t,
         .abstract      = true,
+        .interfaces    = t->interfaces,
     };
     TypeInfo generic_type_info = {
         .name = t->generic_name,
@@ -1961,13 +1954,20 @@ void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t)
 
     if (!base_type_info.name) {
         /* No base type -> register a single generic device type */
-        base_type_info.name = t->generic_name;
-        base_type_info.class_init = virtio_pci_generic_base_class_init;
-        base_type_info.interfaces = generic_type_info.interfaces;
-        base_type_info.abstract = false;
-        generic_type_info.name = NULL;
+        /* use intermediate %s-base-type to add generic device props */
+        base_name = g_strdup_printf("%s-base-type", t->generic_name);
+        base_type_info.name = base_name;
+        base_type_info.class_init = virtio_pci_generic_class_init;
+
+        generic_type_info.parent = base_name;
+        generic_type_info.class_init = virtio_pci_base_class_init;
+        generic_type_info.class_data = (void *)t;
+
         assert(!t->non_transitional_name);
         assert(!t->transitional_name);
+    } else {
+        base_type_info.class_init = virtio_pci_base_class_init;
+        base_type_info.class_data = (void *)t;
     }
 
     type_register(&base_type_info);
@@ -2005,6 +2005,7 @@ void virtio_pci_types_register(const VirtioPCIDeviceTypeInfo *t)
         };
         type_register(&transitional_type_info);
     }
+    g_free(base_name);
 }
 
 /* virtio-pci-bus */
diff --git a/hw/virtio/virtio-pci.h b/hw/virtio/virtio-pci.h
index bfea289..619d909 100644
--- a/hw/virtio/virtio-pci.h
+++ b/hw/virtio/virtio-pci.h
@@ -252,6 +252,7 @@ typedef struct VirtioPCIDeviceTypeInfo {
     size_t class_size;
     void (*instance_init)(Object *obj);
     void (*class_init)(ObjectClass *klass, void *data);
+    InterfaceInfo *interfaces;
 } VirtioPCIDeviceTypeInfo;
 
 /* Register virtio-pci type(s).  @t must be static. */
diff --git a/hw/virtio/virtio-pmem-pci.c b/hw/virtio/virtio-pmem-pci.c
new file mode 100644
index 0000000..8b2d0db
--- /dev/null
+++ b/hw/virtio/virtio-pmem-pci.c
@@ -0,0 +1,131 @@
+/*
+ * Virtio PMEM PCI device
+ *
+ * Copyright (C) 2018-2019 Red Hat, Inc.
+ *
+ * Authors:
+ *  Pankaj Gupta <pagupta@redhat.com>
+ *  David Hildenbrand <david@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include "virtio-pmem-pci.h"
+#include "hw/mem/memory-device.h"
+#include "qapi/error.h"
+
+static void virtio_pmem_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
+{
+    VirtIOPMEMPCI *pmem_pci = VIRTIO_PMEM_PCI(vpci_dev);
+    DeviceState *vdev = DEVICE(&pmem_pci->vdev);
+
+    qdev_set_parent_bus(vdev, BUS(&vpci_dev->bus));
+    object_property_set_bool(OBJECT(vdev), true, "realized", errp);
+}
+
+static void virtio_pmem_pci_set_addr(MemoryDeviceState *md, uint64_t addr,
+                                     Error **errp)
+{
+    object_property_set_uint(OBJECT(md), addr, VIRTIO_PMEM_ADDR_PROP, errp);
+}
+
+static uint64_t virtio_pmem_pci_get_addr(const MemoryDeviceState *md)
+{
+    return object_property_get_uint(OBJECT(md), VIRTIO_PMEM_ADDR_PROP,
+                                    &error_abort);
+}
+
+static MemoryRegion *virtio_pmem_pci_get_memory_region(MemoryDeviceState *md,
+                                                       Error **errp)
+{
+    VirtIOPMEMPCI *pci_pmem = VIRTIO_PMEM_PCI(md);
+    VirtIOPMEM *pmem = VIRTIO_PMEM(&pci_pmem->vdev);
+    VirtIOPMEMClass *vpc = VIRTIO_PMEM_GET_CLASS(pmem);
+
+    return vpc->get_memory_region(pmem, errp);
+}
+
+static uint64_t virtio_pmem_pci_get_plugged_size(const MemoryDeviceState *md,
+                                                 Error **errp)
+{
+    VirtIOPMEMPCI *pci_pmem = VIRTIO_PMEM_PCI(md);
+    VirtIOPMEM *pmem = VIRTIO_PMEM(&pci_pmem->vdev);
+    VirtIOPMEMClass *vpc = VIRTIO_PMEM_GET_CLASS(pmem);
+    MemoryRegion *mr = vpc->get_memory_region(pmem, errp);
+
+    /* the plugged size corresponds to the region size */
+    return mr ? 0 : memory_region_size(mr);
+}
+
+static void virtio_pmem_pci_fill_device_info(const MemoryDeviceState *md,
+                                             MemoryDeviceInfo *info)
+{
+    VirtioPMEMDeviceInfo *vi = g_new0(VirtioPMEMDeviceInfo, 1);
+    VirtIOPMEMPCI *pci_pmem = VIRTIO_PMEM_PCI(md);
+    VirtIOPMEM *pmem = VIRTIO_PMEM(&pci_pmem->vdev);
+    VirtIOPMEMClass *vpc = VIRTIO_PMEM_GET_CLASS(pmem);
+    DeviceState *dev = DEVICE(md);
+
+    if (dev->id) {
+        vi->has_id = true;
+        vi->id = g_strdup(dev->id);
+    }
+
+    /* let the real device handle everything else */
+    vpc->fill_device_info(pmem, vi);
+
+    info->u.virtio_pmem.data = vi;
+    info->type = MEMORY_DEVICE_INFO_KIND_VIRTIO_PMEM;
+}
+
+static void virtio_pmem_pci_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtioPCIClass *k = VIRTIO_PCI_CLASS(klass);
+    PCIDeviceClass *pcidev_k = PCI_DEVICE_CLASS(klass);
+    MemoryDeviceClass *mdc = MEMORY_DEVICE_CLASS(klass);
+
+    k->realize = virtio_pmem_pci_realize;
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+    pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+    pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_PMEM;
+    pcidev_k->revision = VIRTIO_PCI_ABI_VERSION;
+    pcidev_k->class_id = PCI_CLASS_OTHERS;
+
+    mdc->get_addr = virtio_pmem_pci_get_addr;
+    mdc->set_addr = virtio_pmem_pci_set_addr;
+    mdc->get_plugged_size = virtio_pmem_pci_get_plugged_size;
+    mdc->get_memory_region = virtio_pmem_pci_get_memory_region;
+    mdc->fill_device_info = virtio_pmem_pci_fill_device_info;
+}
+
+static void virtio_pmem_pci_instance_init(Object *obj)
+{
+    VirtIOPMEMPCI *dev = VIRTIO_PMEM_PCI(obj);
+
+    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+                                TYPE_VIRTIO_PMEM);
+}
+
+static const VirtioPCIDeviceTypeInfo virtio_pmem_pci_info = {
+    .base_name             = TYPE_VIRTIO_PMEM_PCI,
+    .generic_name          = "virtio-pmem-pci",
+    .transitional_name     = "virtio-pmem-pci-transitional",
+    .non_transitional_name = "virtio-pmem-pci-non-transitional",
+    .instance_size = sizeof(VirtIOPMEMPCI),
+    .instance_init = virtio_pmem_pci_instance_init,
+    .class_init    = virtio_pmem_pci_class_init,
+    .interfaces = (InterfaceInfo[]) {
+        { TYPE_MEMORY_DEVICE },
+        { }
+    },
+};
+
+static void virtio_pmem_pci_register_types(void)
+{
+    virtio_pci_types_register(&virtio_pmem_pci_info);
+}
+type_init(virtio_pmem_pci_register_types)
diff --git a/hw/virtio/virtio-pmem-pci.h b/hw/virtio/virtio-pmem-pci.h
new file mode 100644
index 0000000..616abef
--- /dev/null
+++ b/hw/virtio/virtio-pmem-pci.h
@@ -0,0 +1,34 @@
+/*
+ * Virtio PMEM PCI device
+ *
+ * Copyright (C) 2018-2019 Red Hat, Inc.
+ *
+ * Authors:
+ *  Pankaj Gupta <pagupta@redhat.com>
+ *  David Hildenbrand <david@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef QEMU_VIRTIO_PMEM_PCI_H
+#define QEMU_VIRTIO_PMEM_PCI_H
+
+#include "hw/virtio/virtio-pci.h"
+#include "hw/virtio/virtio-pmem.h"
+
+typedef struct VirtIOPMEMPCI VirtIOPMEMPCI;
+
+/*
+ * virtio-pmem-pci: This extends VirtioPCIProxy.
+ */
+#define TYPE_VIRTIO_PMEM_PCI "virtio-pmem-pci-base"
+#define VIRTIO_PMEM_PCI(obj) \
+        OBJECT_CHECK(VirtIOPMEMPCI, (obj), TYPE_VIRTIO_PMEM_PCI)
+
+struct VirtIOPMEMPCI {
+    VirtIOPCIProxy parent_obj;
+    VirtIOPMEM vdev;
+};
+
+#endif /* QEMU_VIRTIO_PMEM_PCI_H */
diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c
new file mode 100644
index 0000000..adbfb60
--- /dev/null
+++ b/hw/virtio/virtio-pmem.c
@@ -0,0 +1,189 @@
+/*
+ * Virtio PMEM device
+ *
+ * Copyright (C) 2018-2019 Red Hat, Inc.
+ *
+ * Authors:
+ *  Pankaj Gupta <pagupta@redhat.com>
+ *  David Hildenbrand <david@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "hw/virtio/virtio-pmem.h"
+#include "hw/virtio/virtio-access.h"
+#include "standard-headers/linux/virtio_ids.h"
+#include "standard-headers/linux/virtio_pmem.h"
+#include "block/aio.h"
+#include "block/thread-pool.h"
+
+typedef struct VirtIODeviceRequest {
+    VirtQueueElement elem;
+    int fd;
+    VirtIOPMEM *pmem;
+    VirtIODevice *vdev;
+    struct virtio_pmem_req req;
+    struct virtio_pmem_resp resp;
+} VirtIODeviceRequest;
+
+static int worker_cb(void *opaque)
+{
+    VirtIODeviceRequest *req_data = opaque;
+    int err = 0;
+
+    /* flush raw backing image */
+    err = fsync(req_data->fd);
+    if (err != 0) {
+        err = 1;
+    }
+
+    virtio_stw_p(req_data->vdev, &req_data->resp.ret, err);
+
+    return 0;
+}
+
+static void done_cb(void *opaque, int ret)
+{
+    VirtIODeviceRequest *req_data = opaque;
+    int len = iov_from_buf(req_data->elem.in_sg, req_data->elem.in_num, 0,
+                              &req_data->resp, sizeof(struct virtio_pmem_resp));
+
+    /* Callbacks are serialized, so no need to use atomic ops. */
+    virtqueue_push(req_data->pmem->rq_vq, &req_data->elem, len);
+    virtio_notify((VirtIODevice *)req_data->pmem, req_data->pmem->rq_vq);
+    g_free(req_data);
+}
+
+static void virtio_pmem_flush(VirtIODevice *vdev, VirtQueue *vq)
+{
+    VirtIODeviceRequest *req_data;
+    VirtIOPMEM *pmem = VIRTIO_PMEM(vdev);
+    HostMemoryBackend *backend = MEMORY_BACKEND(pmem->memdev);
+    ThreadPool *pool = aio_get_thread_pool(qemu_get_aio_context());
+
+    req_data = virtqueue_pop(vq, sizeof(VirtIODeviceRequest));
+    if (!req_data) {
+        virtio_error(vdev, "virtio-pmem missing request data");
+        return;
+    }
+
+    if (req_data->elem.out_num < 1 || req_data->elem.in_num < 1) {
+        virtio_error(vdev, "virtio-pmem request not proper");
+        g_free(req_data);
+        return;
+    }
+    req_data->fd   = memory_region_get_fd(&backend->mr);
+    req_data->pmem = pmem;
+    req_data->vdev = vdev;
+    thread_pool_submit_aio(pool, worker_cb, req_data, done_cb, req_data);
+}
+
+static void virtio_pmem_get_config(VirtIODevice *vdev, uint8_t *config)
+{
+    VirtIOPMEM *pmem = VIRTIO_PMEM(vdev);
+    struct virtio_pmem_config *pmemcfg = (struct virtio_pmem_config *) config;
+
+    virtio_stq_p(vdev, &pmemcfg->start, pmem->start);
+    virtio_stq_p(vdev, &pmemcfg->size, memory_region_size(&pmem->memdev->mr));
+}
+
+static uint64_t virtio_pmem_get_features(VirtIODevice *vdev, uint64_t features,
+                                        Error **errp)
+{
+    return features;
+}
+
+static void virtio_pmem_realize(DeviceState *dev, Error **errp)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VirtIOPMEM *pmem = VIRTIO_PMEM(dev);
+
+    if (!pmem->memdev) {
+        error_setg(errp, "virtio-pmem memdev not set");
+        return;
+    }
+
+    if (host_memory_backend_is_mapped(pmem->memdev)) {
+        char *path = object_get_canonical_path_component(OBJECT(pmem->memdev));
+        error_setg(errp, "can't use already busy memdev: %s", path);
+        g_free(path);
+        return;
+    }
+
+    host_memory_backend_set_mapped(pmem->memdev, true);
+    virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM,
+                sizeof(struct virtio_pmem_config));
+    pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush);
+}
+
+static void virtio_pmem_unrealize(DeviceState *dev, Error **errp)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VirtIOPMEM *pmem = VIRTIO_PMEM(dev);
+
+    host_memory_backend_set_mapped(pmem->memdev, false);
+    virtio_cleanup(vdev);
+}
+
+static void virtio_pmem_fill_device_info(const VirtIOPMEM *pmem,
+                                         VirtioPMEMDeviceInfo *vi)
+{
+    vi->memaddr = pmem->start;
+    vi->size = pmem->memdev ? memory_region_size(&pmem->memdev->mr) : 0;
+    vi->memdev = object_get_canonical_path(OBJECT(pmem->memdev));
+}
+
+static MemoryRegion *virtio_pmem_get_memory_region(VirtIOPMEM *pmem,
+                                                   Error **errp)
+{
+    if (!pmem->memdev) {
+        error_setg(errp, "'%s' property must be set", VIRTIO_PMEM_MEMDEV_PROP);
+        return NULL;
+    }
+
+    return &pmem->memdev->mr;
+}
+
+static Property virtio_pmem_properties[] = {
+    DEFINE_PROP_UINT64(VIRTIO_PMEM_ADDR_PROP, VirtIOPMEM, start, 0),
+    DEFINE_PROP_LINK(VIRTIO_PMEM_MEMDEV_PROP, VirtIOPMEM, memdev,
+                     TYPE_MEMORY_BACKEND, HostMemoryBackend *),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtio_pmem_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+    VirtIOPMEMClass *vpc = VIRTIO_PMEM_CLASS(klass);
+
+    dc->props = virtio_pmem_properties;
+
+    vdc->realize = virtio_pmem_realize;
+    vdc->unrealize = virtio_pmem_unrealize;
+    vdc->get_config = virtio_pmem_get_config;
+    vdc->get_features = virtio_pmem_get_features;
+
+    vpc->fill_device_info = virtio_pmem_fill_device_info;
+    vpc->get_memory_region = virtio_pmem_get_memory_region;
+}
+
+static TypeInfo virtio_pmem_info = {
+    .name          = TYPE_VIRTIO_PMEM,
+    .parent        = TYPE_VIRTIO_DEVICE,
+    .class_size    = sizeof(VirtIOPMEMClass),
+    .class_init    = virtio_pmem_class_init,
+    .instance_size = sizeof(VirtIOPMEM),
+};
+
+static void virtio_register_types(void)
+{
+    type_register_static(&virtio_pmem_info);
+}
+
+type_init(virtio_register_types)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index e1e90fc..18f9f4c 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -1162,9 +1162,10 @@ int virtio_set_status(VirtIODevice *vdev, uint8_t val)
             }
         }
     }
-    vdev->started = val & VIRTIO_CONFIG_S_DRIVER_OK;
-    if (unlikely(vdev->start_on_kick && vdev->started)) {
-        vdev->start_on_kick = false;
+
+    if ((vdev->status & VIRTIO_CONFIG_S_DRIVER_OK) !=
+        (val & VIRTIO_CONFIG_S_DRIVER_OK)) {
+        virtio_set_started(vdev, val & VIRTIO_CONFIG_S_DRIVER_OK);
     }
 
     if (k->set_status) {
@@ -1214,8 +1215,7 @@ void virtio_reset(void *opaque)
         k->reset(vdev);
     }
 
-    vdev->start_on_kick = (virtio_host_has_feature(vdev, VIRTIO_F_VERSION_1) &&
-                          !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1));
+    vdev->start_on_kick = false;
     vdev->started = false;
     vdev->broken = false;
     vdev->guest_features = 0;
@@ -1536,8 +1536,7 @@ static bool virtio_queue_notify_aio_vq(VirtQueue *vq)
         ret = vq->handle_aio_output(vdev, vq);
 
         if (unlikely(vdev->start_on_kick)) {
-            vdev->started = true;
-            vdev->start_on_kick = false;
+            virtio_set_started(vdev, true);
         }
     }
 
@@ -1557,8 +1556,7 @@ static void virtio_queue_notify_vq(VirtQueue *vq)
         vq->handle_output(vdev, vq);
 
         if (unlikely(vdev->start_on_kick)) {
-            vdev->started = true;
-            vdev->start_on_kick = false;
+            virtio_set_started(vdev, true);
         }
     }
 }
@@ -1576,11 +1574,10 @@ void virtio_queue_notify(VirtIODevice *vdev, int n)
         event_notifier_set(&vq->host_notifier);
     } else if (vq->handle_output) {
         vq->handle_output(vdev, vq);
-    }
 
-    if (unlikely(vdev->start_on_kick)) {
-        vdev->started = true;
-        vdev->start_on_kick = false;
+        if (unlikely(vdev->start_on_kick)) {
+            virtio_set_started(vdev, true);
+        }
     }
 }
 
@@ -2069,14 +2066,21 @@ int virtio_set_features(VirtIODevice *vdev, uint64_t val)
         return -EINVAL;
     }
     ret = virtio_set_features_nocheck(vdev, val);
-    if (!ret && virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) {
-        /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches.  */
-        int i;
-        for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
-            if (vdev->vq[i].vring.num != 0) {
-                virtio_init_region_cache(vdev, i);
+    if (!ret) {
+        if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) {
+            /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches.  */
+            int i;
+            for (i = 0; i < VIRTIO_QUEUE_MAX; i++) {
+                if (vdev->vq[i].vring.num != 0) {
+                    virtio_init_region_cache(vdev, i);
+                }
             }
         }
+
+        if (!virtio_device_started(vdev, vdev->status) &&
+            !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+            vdev->start_on_kick = true;
+        }
     }
     return ret;
 }
@@ -2228,6 +2232,11 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
         }
     }
 
+    if (!virtio_device_started(vdev, vdev->status) &&
+        !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) {
+        vdev->start_on_kick = true;
+    }
+
     rcu_read_lock();
     for (i = 0; i < num; i++) {
         if (vdev->vq[i].vring.desc) {
@@ -2291,7 +2300,7 @@ static void virtio_vmstate_change(void *opaque, int running, RunState state)
     VirtIODevice *vdev = opaque;
     BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
-    bool backend_run = running && vdev->started;
+    bool backend_run = running && virtio_device_started(vdev, vdev->status);
     vdev->vm_running = running;
 
     if (backend_run) {
@@ -2330,8 +2339,7 @@ void virtio_init(VirtIODevice *vdev, const char *name,
             g_malloc0(sizeof(*vdev->vector_queues) * nvectors);
     }
 
-    vdev->start_on_kick = (virtio_host_has_feature(vdev, VIRTIO_F_VERSION_1) &&
-                          !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1));
+    vdev->start_on_kick = false;
     vdev->started = false;
     vdev->device_id = device_id;
     vdev->status = 0;
@@ -2669,6 +2677,7 @@ static void virtio_device_instance_finalize(Object *obj)
 
 static Property virtio_properties[] = {
     DEFINE_VIRTIO_COMMON_FEATURES(VirtIODevice, host_features),
+    DEFINE_PROP_BOOL("use-started", VirtIODevice, use_started, true),
     DEFINE_PROP_END_OF_LIST(),
 };