29 files changed, 1660 insertions, 650 deletions

diff --git a/hw/acpi/aml-build.c b/hw/acpi/aml-build.c
index 3681ec6e3d..2cb7b991ef 100644
--- a/hw/acpi/aml-build.c
+++ b/hw/acpi/aml-build.c
@@ -26,6 +26,7 @@
 #include "qemu/bitops.h"
 #include "sysemu/numa.h"
 #include "hw/boards.h"
+#include "hw/acpi/tpm.h"
 
 static GArray *build_alloc_array(void)
 {
@@ -1865,9 +1866,9 @@ void build_fadt(GArray *tbl, BIOSLinker *linker, const AcpiFadtData *f,
     }
 
     /* SLEEP_CONTROL_REG */
-    build_append_gas(tbl, AML_AS_SYSTEM_MEMORY, 0 , 0, 0, 0);
+    build_append_gas_from_struct(tbl, &f->sleep_ctl);
     /* SLEEP_STATUS_REG */
-    build_append_gas(tbl, AML_AS_SYSTEM_MEMORY, 0 , 0, 0, 0);
+    build_append_gas_from_struct(tbl, &f->sleep_sts);
 
     /* TODO: extra fields need to be added to support revisions above rev5 */
     assert(f->rev == 5);
@@ -1877,6 +1878,50 @@ build_hdr:
                  "FACP", tbl->len - fadt_start, f->rev, oem_id, oem_table_id);
 }
 
+void build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog)
+{
+    Acpi20TPM2 *tpm2_ptr = acpi_data_push(table_data, sizeof(AcpiTableHeader));
+    unsigned log_addr_size = sizeof(tpm2_ptr->log_area_start_address);
+    unsigned log_addr_offset =
+        (char *)&tpm2_ptr->log_area_start_address - table_data->data;
+    uint8_t start_method_params[12] = {};
+    TPMIf *tpmif = tpm_find();
+
+    /* platform class */
+    build_append_int_noprefix(table_data, TPM2_ACPI_CLASS_CLIENT, 2);
+    /* reserved */
+    build_append_int_noprefix(table_data, 0, 2);
+    if (TPM_IS_TIS_ISA(tpmif) || TPM_IS_TIS_SYSBUS(tpmif)) {
+        /* address of control area */
+        build_append_int_noprefix(table_data, 0, 8);
+        /* start method */
+        build_append_int_noprefix(table_data, TPM2_START_METHOD_MMIO, 4);
+    } else if (TPM_IS_CRB(tpmif)) {
+        build_append_int_noprefix(table_data, TPM_CRB_ADDR_CTRL, 8);
+        build_append_int_noprefix(table_data, TPM2_START_METHOD_CRB, 4);
+    } else {
+        g_warn_if_reached();
+    }
+
+    /* platform specific parameters */
+    g_array_append_vals(table_data, &start_method_params, 12);
+
+    /* log area minimum length */
+    build_append_int_noprefix(table_data, TPM_LOG_AREA_MINIMUM_SIZE, 4);
+
+    acpi_data_push(tcpalog, TPM_LOG_AREA_MINIMUM_SIZE);
+    bios_linker_loader_alloc(linker, ACPI_BUILD_TPMLOG_FILE, tcpalog, 1,
+                             false);
+
+    /* log area start address to be filled by Guest linker */
+    build_append_int_noprefix(table_data, 0, 8);
+    bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
+                                   log_addr_offset, log_addr_size,
+                                   ACPI_BUILD_TPMLOG_FILE, 0);
+    build_header(linker, table_data,
+                 (void *)tpm2_ptr, "TPM2", sizeof(*tpm2_ptr), 4, NULL, NULL);
+}
+
 /* ACPI 5.0: 6.4.3.8.2 Serial Bus Connection Descriptors */
 static Aml *aml_serial_bus_device(uint8_t serial_bus_type, uint8_t flags,
                                   uint16_t type_flags,
diff --git a/hw/acpi/generic_event_device.c b/hw/acpi/generic_event_device.c
index b1cbdd86b6..1cb34111e5 100644
--- a/hw/acpi/generic_event_device.c
+++ b/hw/acpi/generic_event_device.c
@@ -142,7 +142,7 @@ void build_ged_aml(Aml *table, const char *name, HotplugHandler *hotplug_dev,
 }
 
 /* Memory read by the GED _EVT AML dynamic method */
-static uint64_t ged_read(void *opaque, hwaddr addr, unsigned size)
+static uint64_t ged_evt_read(void *opaque, hwaddr addr, unsigned size)
 {
     uint64_t val = 0;
     GEDState *ged_st = opaque;
@@ -161,14 +161,14 @@ static uint64_t ged_read(void *opaque, hwaddr addr, unsigned size)
 }
 
 /* Nothing is expected to be written to the GED memory region */
-static void ged_write(void *opaque, hwaddr addr, uint64_t data,
-                      unsigned int size)
+static void ged_evt_write(void *opaque, hwaddr addr, uint64_t data,
+                          unsigned int size)
 {
 }
 
-static const MemoryRegionOps ged_ops = {
-    .read = ged_read,
-    .write = ged_write,
+static const MemoryRegionOps ged_evt_ops = {
+    .read = ged_evt_read,
+    .write = ged_evt_write,
     .endianness = DEVICE_LITTLE_ENDIAN,
     .valid = {
         .min_access_size = 4,
@@ -287,9 +287,9 @@ static void acpi_ged_initfn(Object *obj)
     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
     GEDState *ged_st = &s->ged_state;
 
-    memory_region_init_io(&ged_st->io, obj, &ged_ops, ged_st,
+    memory_region_init_io(&ged_st->evt, obj, &ged_evt_ops, ged_st,
                           TYPE_ACPI_GED, ACPI_GED_EVT_SEL_LEN);
-    sysbus_init_mmio(sbd, &ged_st->io);
+    sysbus_init_mmio(sbd, &ged_st->evt);
 
     sysbus_init_irq(sbd, &s->irq);
 
diff --git a/hw/acpi/nvdimm.c b/hw/acpi/nvdimm.c
index 9316d12b70..8f7cc16add 100644
--- a/hw/acpi/nvdimm.c
+++ b/hw/acpi/nvdimm.c
@@ -28,6 +28,7 @@
 
 #include "qemu/osdep.h"
 #include "qemu/uuid.h"
+#include "qapi/error.h"
 #include "hw/acpi/acpi.h"
 #include "hw/acpi/aml-build.h"
 #include "hw/acpi/bios-linker-loader.h"
@@ -1334,6 +1335,28 @@ static void nvdimm_build_ssdt(GArray *table_offsets, GArray *table_data,
     free_aml_allocator();
 }
 
+void nvdimm_build_srat(GArray *table_data)
+{
+    GSList *device_list = nvdimm_get_device_list();
+
+    for (; device_list; device_list = device_list->next) {
+        AcpiSratMemoryAffinity *numamem = NULL;
+        DeviceState *dev = device_list->data;
+        Object *obj = OBJECT(dev);
+        uint64_t addr, size;
+        int node;
+
+        node = object_property_get_int(obj, PC_DIMM_NODE_PROP, &error_abort);
+        addr = object_property_get_uint(obj, PC_DIMM_ADDR_PROP, &error_abort);
+        size = object_property_get_uint(obj, PC_DIMM_SIZE_PROP, &error_abort);
+
+        numamem = acpi_data_push(table_data, sizeof *numamem);
+        build_srat_memory(numamem, addr, size, node,
+                          MEM_AFFINITY_ENABLED | MEM_AFFINITY_NON_VOLATILE);
+    }
+    g_slist_free(device_list);
+}
+
 void nvdimm_build_acpi(GArray *table_offsets, GArray *table_data,
                        BIOSLinker *linker, NVDIMMState *state,
                        uint32_t ram_slots)
diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
index 1b0a584c7b..ca31f70f7f 100644
--- a/hw/arm/virt-acpi-build.c
+++ b/hw/arm/virt-acpi-build.c
@@ -41,12 +41,14 @@
 #include "hw/acpi/pci.h"
 #include "hw/acpi/memory_hotplug.h"
 #include "hw/acpi/generic_event_device.h"
+#include "hw/acpi/tpm.h"
 #include "hw/pci/pcie_host.h"
 #include "hw/pci/pci.h"
 #include "hw/arm/virt.h"
 #include "hw/mem/nvdimm.h"
 #include "sysemu/numa.h"
 #include "sysemu/reset.h"
+#include "sysemu/tpm.h"
 #include "kvm_arm.h"
 #include "migration/vmstate.h"
 #include "hw/acpi/ghes.h"
@@ -539,6 +541,10 @@ build_srat(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
         }
     }
 
+    if (ms->nvdimms_state->is_enabled) {
+        nvdimm_build_srat(table_data);
+    }
+
     if (ms->device_memory) {
         numamem = acpi_data_push(table_data, sizeof *numamem);
         build_srat_memory(numamem, ms->device_memory->base,
@@ -844,6 +850,11 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables)
         build_iort(tables_blob, tables->linker, vms);
     }
 
+    if (tpm_get_version(tpm_find()) == TPM_VERSION_2_0) {
+        acpi_add_table(table_offsets, tables_blob);
+        build_tpm2(tables_blob, tables->linker, tables->tcpalog);
+    }
+
     /* XSDT is pointed to by RSDP */
     xsdt = tables_blob->len;
     build_xsdt(tables_blob, tables->linker, table_offsets, NULL, NULL);
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index 9d8c0b3909..76838e76d3 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -349,6 +349,19 @@ static void vhost_user_blk_disconnect(DeviceState *dev)
     vhost_dev_cleanup(&s->dev);
 }
 
+static void vhost_user_blk_event(void *opaque, QEMUChrEvent event);
+
+static void vhost_user_blk_chr_closed_bh(void *opaque)
+{
+    DeviceState *dev = opaque;
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserBlk *s = VHOST_USER_BLK(vdev);
+
+    vhost_user_blk_disconnect(dev);
+    qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, vhost_user_blk_event,
+            NULL, opaque, NULL, true);
+}
+
 static void vhost_user_blk_event(void *opaque, QEMUChrEvent event)
 {
     DeviceState *dev = opaque;
@@ -363,7 +376,30 @@ static void vhost_user_blk_event(void *opaque, QEMUChrEvent event)
         }
         break;
     case CHR_EVENT_CLOSED:
-        vhost_user_blk_disconnect(dev);
+        /*
+         * A close event may happen during a read/write, but vhost
+         * code assumes the vhost_dev remains setup, so delay the
+         * stop & clear. There are two possible paths to hit this
+         * disconnect event:
+         * 1. When VM is in the RUN_STATE_PRELAUNCH state. The
+         * vhost_user_blk_device_realize() is a caller.
+         * 2. In tha main loop phase after VM start.
+         *
+         * For p2 the disconnect event will be delayed. We can't
+         * do the same for p1, because we are not running the loop
+         * at this moment. So just skip this step and perform
+         * disconnect in the caller function.
+         *
+         * TODO: maybe it is a good idea to make the same fix
+         * for other vhost-user devices.
+         */
+        if (runstate_is_running()) {
+            AioContext *ctx = qemu_get_current_aio_context();
+
+            qemu_chr_fe_set_handlers(&s->chardev, NULL, NULL, NULL, NULL,
+                    NULL, NULL, false);
+            aio_bh_schedule_oneshot(ctx, vhost_user_blk_chr_closed_bh, opaque);
+        }
         break;
     case CHR_EVENT_BREAK:
     case CHR_EVENT_MUX_IN:
diff --git a/hw/char/parallel.c b/hw/char/parallel.c
index 8dd67d1375..c0f34bf924 100644
--- a/hw/char/parallel.c
+++ b/hw/char/parallel.c
@@ -28,6 +28,7 @@
 #include "qemu/module.h"
 #include "chardev/char-parallel.h"
 #include "chardev/char-fe.h"
+#include "hw/acpi/aml-build.h"
 #include "hw/irq.h"
 #include "hw/isa/isa.h"
 #include "hw/qdev-properties.h"
@@ -568,6 +569,25 @@ static void parallel_isa_realizefn(DeviceState *dev, Error **errp)
                              s, "parallel");
 }
 
+static void parallel_isa_build_aml(ISADevice *isadev, Aml *scope)
+{
+    ISAParallelState *isa = ISA_PARALLEL(isadev);
+    Aml *dev;
+    Aml *crs;
+
+    crs = aml_resource_template();
+    aml_append(crs, aml_io(AML_DECODE16, isa->iobase, isa->iobase, 0x08, 0x08));
+    aml_append(crs, aml_irq_no_flags(isa->isairq));
+
+    dev = aml_device("LPT%d", isa->index + 1);
+    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0400")));
+    aml_append(dev, aml_name_decl("_UID", aml_int(isa->index + 1)));
+    aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
+    aml_append(dev, aml_name_decl("_CRS", crs));
+
+    aml_append(scope, dev);
+}
+
 /* Memory mapped interface */
 static uint64_t parallel_mm_readfn(void *opaque, hwaddr addr, unsigned size)
 {
@@ -624,9 +644,11 @@ static Property parallel_isa_properties[] = {
 static void parallel_isa_class_initfn(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    ISADeviceClass *isa = ISA_DEVICE_CLASS(klass);
 
     dc->realize = parallel_isa_realizefn;
     dc->vmsd = &vmstate_parallel_isa;
+    isa->build_aml = parallel_isa_build_aml;
     device_class_set_props(dc, parallel_isa_properties);
     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 }
diff --git a/hw/char/serial-isa.c b/hw/char/serial-isa.c
index f9b6eed783..165e320e65 100644
--- a/hw/char/serial-isa.c
+++ b/hw/char/serial-isa.c
@@ -27,6 +27,7 @@
 #include "qapi/error.h"
 #include "qemu/module.h"
 #include "sysemu/sysemu.h"
+#include "hw/acpi/aml-build.h"
 #include "hw/char/serial.h"
 #include "hw/isa/isa.h"
 #include "hw/qdev-properties.h"
@@ -81,6 +82,25 @@ static void serial_isa_realizefn(DeviceState *dev, Error **errp)
     isa_register_ioport(isadev, &s->io, isa->iobase);
 }
 
+static void serial_isa_build_aml(ISADevice *isadev, Aml *scope)
+{
+    ISASerialState *isa = ISA_SERIAL(isadev);
+    Aml *dev;
+    Aml *crs;
+
+    crs = aml_resource_template();
+    aml_append(crs, aml_io(AML_DECODE16, isa->iobase, isa->iobase, 0x00, 0x08));
+    aml_append(crs, aml_irq_no_flags(isa->isairq));
+
+    dev = aml_device("COM%d", isa->index + 1);
+    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0501")));
+    aml_append(dev, aml_name_decl("_UID", aml_int(isa->index + 1)));
+    aml_append(dev, aml_name_decl("_STA", aml_int(0xf)));
+    aml_append(dev, aml_name_decl("_CRS", crs));
+
+    aml_append(scope, dev);
+}
+
 static const VMStateDescription vmstate_isa_serial = {
     .name = "serial",
     .version_id = 3,
@@ -103,9 +123,11 @@ static Property serial_isa_properties[] = {
 static void serial_isa_class_initfn(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    ISADeviceClass *isa = ISA_DEVICE_CLASS(klass);
 
     dc->realize = serial_isa_realizefn;
     dc->vmsd = &vmstate_isa_serial;
+    isa->build_aml = serial_isa_build_aml;
     device_class_set_props(dc, serial_isa_properties);
     set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
 }
diff --git a/hw/core/machine.c b/hw/core/machine.c
index bb3a7b18b1..9eca7d8c9b 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -28,7 +28,9 @@
 #include "hw/mem/nvdimm.h"
 #include "migration/vmstate.h"
 
-GlobalProperty hw_compat_5_0[] = {};
+GlobalProperty hw_compat_5_0[] = {
+    { "virtio-balloon-device", "page-poison", "false" },
+};
 const size_t hw_compat_5_0_len = G_N_ELEMENTS(hw_compat_5_0);
 
 GlobalProperty hw_compat_4_2[] = {
diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
index 8ce1b26533..6abc74551a 100644
--- a/hw/i386/Makefile.objs
+++ b/hw/i386/Makefile.objs
@@ -16,4 +16,5 @@ obj-$(CONFIG_VMMOUSE) += vmmouse.o
 obj-$(CONFIG_PC) += port92.o
 
 obj-y += kvmvapic.o
+obj-$(CONFIG_ACPI) += acpi-common.o
 obj-$(CONFIG_PC) += acpi-build.o
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 2e15f6848e..473cbdfffd 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -24,6 +24,7 @@
 #include "qapi/error.h"
 #include "qapi/qmp/qnum.h"
 #include "acpi-build.h"
+#include "acpi-common.h"
 #include "qemu/bitmap.h"
 #include "qemu/error-report.h"
 #include "hw/pci/pci.h"
@@ -89,9 +90,6 @@
 #define ACPI_BUILD_DPRINTF(fmt, ...)
 #endif
 
-/* Default IOAPIC ID */
-#define ACPI_BUILD_IOAPIC_ID 0x0
-
 typedef struct AcpiPmInfo {
     bool s3_disabled;
     bool s4_disabled;
@@ -327,125 +325,6 @@ build_facs(GArray *table_data)
     facs->length = cpu_to_le32(sizeof(*facs));
 }
 
-void pc_madt_cpu_entry(AcpiDeviceIf *adev, int uid,
-                       const CPUArchIdList *apic_ids, GArray *entry)
-{
-    uint32_t apic_id = apic_ids->cpus[uid].arch_id;
-
-    /* ACPI spec says that LAPIC entry for non present
-     * CPU may be omitted from MADT or it must be marked
-     * as disabled. However omitting non present CPU from
-     * MADT breaks hotplug on linux. So possible CPUs
-     * should be put in MADT but kept disabled.
-     */
-    if (apic_id < 255) {
-        AcpiMadtProcessorApic *apic = acpi_data_push(entry, sizeof *apic);
-
-        apic->type = ACPI_APIC_PROCESSOR;
-        apic->length = sizeof(*apic);
-        apic->processor_id = uid;
-        apic->local_apic_id = apic_id;
-        if (apic_ids->cpus[uid].cpu != NULL) {
-            apic->flags = cpu_to_le32(1);
-        } else {
-            apic->flags = cpu_to_le32(0);
-        }
-    } else {
-        AcpiMadtProcessorX2Apic *apic = acpi_data_push(entry, sizeof *apic);
-
-        apic->type = ACPI_APIC_LOCAL_X2APIC;
-        apic->length = sizeof(*apic);
-        apic->uid = cpu_to_le32(uid);
-        apic->x2apic_id = cpu_to_le32(apic_id);
-        if (apic_ids->cpus[uid].cpu != NULL) {
-            apic->flags = cpu_to_le32(1);
-        } else {
-            apic->flags = cpu_to_le32(0);
-        }
-    }
-}
-
-static void
-build_madt(GArray *table_data, BIOSLinker *linker, PCMachineState *pcms)
-{
-    MachineClass *mc = MACHINE_GET_CLASS(pcms);
-    X86MachineState *x86ms = X86_MACHINE(pcms);
-    const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(MACHINE(pcms));
-    int madt_start = table_data->len;
-    AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(pcms->acpi_dev);
-    AcpiDeviceIf *adev = ACPI_DEVICE_IF(pcms->acpi_dev);
-    bool x2apic_mode = false;
-
-    AcpiMultipleApicTable *madt;
-    AcpiMadtIoApic *io_apic;
-    AcpiMadtIntsrcovr *intsrcovr;
-    int i;
-
-    madt = acpi_data_push(table_data, sizeof *madt);
-    madt->local_apic_address = cpu_to_le32(APIC_DEFAULT_ADDRESS);
-    madt->flags = cpu_to_le32(1);
-
-    for (i = 0; i < apic_ids->len; i++) {
-        adevc->madt_cpu(adev, i, apic_ids, table_data);
-        if (apic_ids->cpus[i].arch_id > 254) {
-            x2apic_mode = true;
-        }
-    }
-
-    io_apic = acpi_data_push(table_data, sizeof *io_apic);
-    io_apic->type = ACPI_APIC_IO;
-    io_apic->length = sizeof(*io_apic);
-    io_apic->io_apic_id = ACPI_BUILD_IOAPIC_ID;
-    io_apic->address = cpu_to_le32(IO_APIC_DEFAULT_ADDRESS);
-    io_apic->interrupt = cpu_to_le32(0);
-
-    if (x86ms->apic_xrupt_override) {
-        intsrcovr = acpi_data_push(table_data, sizeof *intsrcovr);
-        intsrcovr->type   = ACPI_APIC_XRUPT_OVERRIDE;
-        intsrcovr->length = sizeof(*intsrcovr);
-        intsrcovr->source = 0;
-        intsrcovr->gsi    = cpu_to_le32(2);
-        intsrcovr->flags  = cpu_to_le16(0); /* conforms to bus specifications */
-    }
-    for (i = 1; i < 16; i++) {
-#define ACPI_BUILD_PCI_IRQS ((1<<5) | (1<<9) | (1<<10) | (1<<11))
-        if (!(ACPI_BUILD_PCI_IRQS & (1 << i))) {
-            /* No need for a INT source override structure. */
-            continue;
-        }
-        intsrcovr = acpi_data_push(table_data, sizeof *intsrcovr);
-        intsrcovr->type   = ACPI_APIC_XRUPT_OVERRIDE;
-        intsrcovr->length = sizeof(*intsrcovr);
-        intsrcovr->source = i;
-        intsrcovr->gsi    = cpu_to_le32(i);
-        intsrcovr->flags  = cpu_to_le16(0xd); /* active high, level triggered */
-    }
-
-    if (x2apic_mode) {
-        AcpiMadtLocalX2ApicNmi *local_nmi;
-
-        local_nmi = acpi_data_push(table_data, sizeof *local_nmi);
-        local_nmi->type   = ACPI_APIC_LOCAL_X2APIC_NMI;
-        local_nmi->length = sizeof(*local_nmi);
-        local_nmi->uid    = 0xFFFFFFFF; /* all processors */
-        local_nmi->flags  = cpu_to_le16(0);
-        local_nmi->lint   = 1; /* ACPI_LINT1 */
-    } else {
-        AcpiMadtLocalNmi *local_nmi;
-
-        local_nmi = acpi_data_push(table_data, sizeof *local_nmi);
-        local_nmi->type         = ACPI_APIC_LOCAL_NMI;
-        local_nmi->length       = sizeof(*local_nmi);
-        local_nmi->processor_id = 0xff; /* all processors */
-        local_nmi->flags        = cpu_to_le16(0);
-        local_nmi->lint         = 1; /* ACPI_LINT1 */
-    }
-
-    build_header(linker, table_data,
-                 (void *)(table_data->data + madt_start), "APIC",
-                 table_data->len - madt_start, 1, NULL, NULL);
-}
-
 static void build_append_pcihp_notify_entry(Aml *method, int slot)
 {
     Aml *if_ctx;
@@ -1137,22 +1016,6 @@ static Aml *build_fdc_device_aml(ISADevice *fdc)
     return dev;
 }
 
-static Aml *build_rtc_device_aml(void)
-{
-    Aml *dev;
-    Aml *crs;
-
-    dev = aml_device("RTC");
-    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0B00")));
-    crs = aml_resource_template();
-    aml_append(crs, aml_io(AML_DECODE16, 0x0070, 0x0070, 0x10, 0x02));
-    aml_append(crs, aml_irq_no_flags(8));
-    aml_append(crs, aml_io(AML_DECODE16, 0x0072, 0x0072, 0x02, 0x06));
-    aml_append(dev, aml_name_decl("_CRS", crs));
-
-    return dev;
-}
-
 static Aml *build_kbd_device_aml(void)
 {
     Aml *dev;
@@ -1189,87 +1052,6 @@ static Aml *build_mouse_device_aml(void)
     return dev;
 }
 
-static Aml *build_lpt_device_aml(void)
-{
-    Aml *dev;
-    Aml *crs;
-    Aml *method;
-    Aml *if_ctx;
-    Aml *else_ctx;
-    Aml *zero = aml_int(0);
-    Aml *is_present = aml_local(0);
-
-    dev = aml_device("LPT");
-    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0400")));
-
-    method = aml_method("_STA", 0, AML_NOTSERIALIZED);
-    aml_append(method, aml_store(aml_name("LPEN"), is_present));
-    if_ctx = aml_if(aml_equal(is_present, zero));
-    {
-        aml_append(if_ctx, aml_return(aml_int(0x00)));
-    }
-    aml_append(method, if_ctx);
-    else_ctx = aml_else();
-    {
-        aml_append(else_ctx, aml_return(aml_int(0x0f)));
-    }
-    aml_append(method, else_ctx);
-    aml_append(dev, method);
-
-    crs = aml_resource_template();
-    aml_append(crs, aml_io(AML_DECODE16, 0x0378, 0x0378, 0x08, 0x08));
-    aml_append(crs, aml_irq_no_flags(7));
-    aml_append(dev, aml_name_decl("_CRS", crs));
-
-    return dev;
-}
-
-static Aml *build_com_device_aml(uint8_t uid)
-{
-    Aml *dev;
-    Aml *crs;
-    Aml *method;
-    Aml *if_ctx;
-    Aml *else_ctx;
-    Aml *zero = aml_int(0);
-    Aml *is_present = aml_local(0);
-    const char *enabled_field = "CAEN";
-    uint8_t irq = 4;
-    uint16_t io_port = 0x03F8;
-
-    assert(uid == 1 || uid == 2);
-    if (uid == 2) {
-        enabled_field = "CBEN";
-        irq = 3;
-        io_port = 0x02F8;
-    }
-
-    dev = aml_device("COM%d", uid);
-    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0501")));
-    aml_append(dev, aml_name_decl("_UID", aml_int(uid)));
-
-    method = aml_method("_STA", 0, AML_NOTSERIALIZED);
-    aml_append(method, aml_store(aml_name("%s", enabled_field), is_present));
-    if_ctx = aml_if(aml_equal(is_present, zero));
-    {
-        aml_append(if_ctx, aml_return(aml_int(0x00)));
-    }
-    aml_append(method, if_ctx);
-    else_ctx = aml_else();
-    {
-        aml_append(else_ctx, aml_return(aml_int(0x0f)));
-    }
-    aml_append(method, else_ctx);
-    aml_append(dev, method);
-
-    crs = aml_resource_template();
-    aml_append(crs, aml_io(AML_DECODE16, io_port, io_port, 0x00, 0x08));
-    aml_append(crs, aml_irq_no_flags(irq));
-    aml_append(dev, aml_name_decl("_CRS", crs));
-
-    return dev;
-}
-
 static void build_isa_devices_aml(Aml *table)
 {
     ISADevice *fdc = pc_find_fdc0();
@@ -1278,15 +1060,11 @@ static void build_isa_devices_aml(Aml *table)
     Aml *scope = aml_scope("_SB.PCI0.ISA");
     Object *obj = object_resolve_path_type("", TYPE_ISA_BUS, &ambiguous);
 
-    aml_append(scope, build_rtc_device_aml());
     aml_append(scope, build_kbd_device_aml());
     aml_append(scope, build_mouse_device_aml());
     if (fdc) {
         aml_append(scope, build_fdc_device_aml(fdc));
     }
-    aml_append(scope, build_lpt_device_aml());
-    aml_append(scope, build_com_device_aml(1));
-    aml_append(scope, build_com_device_aml(2));
 
     if (ambiguous) {
         error_report("Multiple ISA busses, unable to define IPMI ACPI data");
@@ -2295,36 +2073,6 @@ build_tpm_tcpa(GArray *table_data, BIOSLinker *linker, GArray *tcpalog)
                  (void *)tcpa, "TCPA", sizeof(*tcpa), 2, NULL, NULL);
 }
 
-static void
-build_tpm2(GArray *table_data, BIOSLinker *linker, GArray *tcpalog)
-{
-    Acpi20TPM2 *tpm2_ptr = acpi_data_push(table_data, sizeof *tpm2_ptr);
-    unsigned log_addr_size = sizeof(tpm2_ptr->log_area_start_address);
-    unsigned log_addr_offset =
-        (char *)&tpm2_ptr->log_area_start_address - table_data->data;
-
-    tpm2_ptr->platform_class = cpu_to_le16(TPM2_ACPI_CLASS_CLIENT);
-    if (TPM_IS_TIS_ISA(tpm_find())) {
-        tpm2_ptr->control_area_address = cpu_to_le64(0);
-        tpm2_ptr->start_method = cpu_to_le32(TPM2_START_METHOD_MMIO);
-    } else if (TPM_IS_CRB(tpm_find())) {
-        tpm2_ptr->control_area_address = cpu_to_le64(TPM_CRB_ADDR_CTRL);
-        tpm2_ptr->start_method = cpu_to_le32(TPM2_START_METHOD_CRB);
-    } else {
-        g_warn_if_reached();
-    }
-
-    tpm2_ptr->log_area_minimum_length =
-        cpu_to_le32(TPM_LOG_AREA_MINIMUM_SIZE);
-
-    /* log area start address to be filled by Guest linker */
-    bios_linker_loader_add_pointer(linker, ACPI_BUILD_TABLE_FILE,
-                                   log_addr_offset, log_addr_size,
-                                   ACPI_BUILD_TPMLOG_FILE, 0);
-    build_header(linker, table_data,
-                 (void *)tpm2_ptr, "TPM2", sizeof(*tpm2_ptr), 4, NULL, NULL);
-}
-
 #define HOLE_640K_START  (640 * KiB)
 #define HOLE_640K_END   (1 * MiB)
 
@@ -2428,6 +2176,11 @@ build_srat(GArray *table_data, BIOSLinker *linker, MachineState *machine)
                               MEM_AFFINITY_ENABLED);
         }
     }
+
+    if (machine->nvdimms_state->is_enabled) {
+        nvdimm_build_srat(table_data);
+    }
+
     slots = (table_data->len - numa_start) / sizeof *numamem;
     for (; slots < pcms->numa_nodes + 2; slots++) {
         numamem = acpi_data_push(table_data, sizeof *numamem);
@@ -2834,7 +2587,8 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
     aml_len += tables_blob->len - fadt;
 
     acpi_add_table(table_offsets, tables_blob);
-    build_madt(tables_blob, tables->linker, pcms);
+    acpi_build_madt(tables_blob, tables->linker, x86ms,
+                    ACPI_DEVICE_IF(pcms->acpi_dev), true);
 
     vmgenid_dev = find_vmgenid_dev();
     if (vmgenid_dev) {
@@ -2848,10 +2602,10 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
         build_hpet(tables_blob, tables->linker);
     }
     if (misc.tpm_version != TPM_VERSION_UNSPEC) {
-        acpi_add_table(table_offsets, tables_blob);
-        build_tpm_tcpa(tables_blob, tables->linker, tables->tcpalog);
-
-        if (misc.tpm_version == TPM_VERSION_2_0) {
+        if (misc.tpm_version == TPM_VERSION_1_2) {
+            acpi_add_table(table_offsets, tables_blob);
+            build_tpm_tcpa(tables_blob, tables->linker, tables->tcpalog);
+        } else { /* TPM_VERSION_2_0 */
             acpi_add_table(table_offsets, tables_blob);
             build_tpm2(tables_blob, tables->linker, tables->tcpalog);
         }
diff --git a/hw/i386/acpi-common.c b/hw/i386/acpi-common.c
new file mode 100644
index 0000000000..ab9b00581a
--- /dev/null
+++ b/hw/i386/acpi-common.c
@@ -0,0 +1,156 @@
+/* Support for generating ACPI tables and passing them to Guests
+ *
+ * Copyright (C) 2008-2010  Kevin O'Connor <kevin@koconnor.net>
+ * Copyright (C) 2006 Fabrice Bellard
+ * Copyright (C) 2013 Red Hat Inc
+ *
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+
+#include "exec/memory.h"
+#include "hw/acpi/acpi.h"
+#include "hw/acpi/aml-build.h"
+#include "hw/acpi/utils.h"
+#include "hw/i386/pc.h"
+#include "target/i386/cpu.h"
+
+#include "acpi-build.h"
+#include "acpi-common.h"
+
+void pc_madt_cpu_entry(AcpiDeviceIf *adev, int uid,
+                       const CPUArchIdList *apic_ids, GArray *entry)
+{
+    uint32_t apic_id = apic_ids->cpus[uid].arch_id;
+
+    /* ACPI spec says that LAPIC entry for non present
+     * CPU may be omitted from MADT or it must be marked
+     * as disabled. However omitting non present CPU from
+     * MADT breaks hotplug on linux. So possible CPUs
+     * should be put in MADT but kept disabled.
+     */
+    if (apic_id < 255) {
+        AcpiMadtProcessorApic *apic = acpi_data_push(entry, sizeof *apic);
+
+        apic->type = ACPI_APIC_PROCESSOR;
+        apic->length = sizeof(*apic);
+        apic->processor_id = uid;
+        apic->local_apic_id = apic_id;
+        if (apic_ids->cpus[uid].cpu != NULL) {
+            apic->flags = cpu_to_le32(1);
+        } else {
+            apic->flags = cpu_to_le32(0);
+        }
+    } else {
+        AcpiMadtProcessorX2Apic *apic = acpi_data_push(entry, sizeof *apic);
+
+        apic->type = ACPI_APIC_LOCAL_X2APIC;
+        apic->length = sizeof(*apic);
+        apic->uid = cpu_to_le32(uid);
+        apic->x2apic_id = cpu_to_le32(apic_id);
+        if (apic_ids->cpus[uid].cpu != NULL) {
+            apic->flags = cpu_to_le32(1);
+        } else {
+            apic->flags = cpu_to_le32(0);
+        }
+    }
+}
+
+void acpi_build_madt(GArray *table_data, BIOSLinker *linker,
+                     X86MachineState *x86ms, AcpiDeviceIf *adev,
+                     bool has_pci)
+{
+    MachineClass *mc = MACHINE_GET_CLASS(x86ms);
+    const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(MACHINE(x86ms));
+    int madt_start = table_data->len;
+    AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(adev);
+    bool x2apic_mode = false;
+
+    AcpiMultipleApicTable *madt;
+    AcpiMadtIoApic *io_apic;
+    AcpiMadtIntsrcovr *intsrcovr;
+    int i;
+
+    madt = acpi_data_push(table_data, sizeof *madt);
+    madt->local_apic_address = cpu_to_le32(APIC_DEFAULT_ADDRESS);
+    madt->flags = cpu_to_le32(1);
+
+    for (i = 0; i < apic_ids->len; i++) {
+        adevc->madt_cpu(adev, i, apic_ids, table_data);
+        if (apic_ids->cpus[i].arch_id > 254) {
+            x2apic_mode = true;
+        }
+    }
+
+    io_apic = acpi_data_push(table_data, sizeof *io_apic);
+    io_apic->type = ACPI_APIC_IO;
+    io_apic->length = sizeof(*io_apic);
+    io_apic->io_apic_id = ACPI_BUILD_IOAPIC_ID;
+    io_apic->address = cpu_to_le32(IO_APIC_DEFAULT_ADDRESS);
+    io_apic->interrupt = cpu_to_le32(0);
+
+    if (x86ms->apic_xrupt_override) {
+        intsrcovr = acpi_data_push(table_data, sizeof *intsrcovr);
+        intsrcovr->type   = ACPI_APIC_XRUPT_OVERRIDE;
+        intsrcovr->length = sizeof(*intsrcovr);
+        intsrcovr->source = 0;
+        intsrcovr->gsi    = cpu_to_le32(2);
+        intsrcovr->flags  = cpu_to_le16(0); /* conforms to bus specifications */
+    }
+
+    if (has_pci) {
+        for (i = 1; i < 16; i++) {
+#define ACPI_BUILD_PCI_IRQS ((1<<5) | (1<<9) | (1<<10) | (1<<11))
+            if (!(ACPI_BUILD_PCI_IRQS & (1 << i))) {
+                /* No need for a INT source override structure. */
+                continue;
+            }
+            intsrcovr = acpi_data_push(table_data, sizeof *intsrcovr);
+            intsrcovr->type   = ACPI_APIC_XRUPT_OVERRIDE;
+            intsrcovr->length = sizeof(*intsrcovr);
+            intsrcovr->source = i;
+            intsrcovr->gsi    = cpu_to_le32(i);
+            intsrcovr->flags  = cpu_to_le16(0xd); /* active high, level triggered */
+        }
+    }
+
+    if (x2apic_mode) {
+        AcpiMadtLocalX2ApicNmi *local_nmi;
+
+        local_nmi = acpi_data_push(table_data, sizeof *local_nmi);
+        local_nmi->type   = ACPI_APIC_LOCAL_X2APIC_NMI;
+        local_nmi->length = sizeof(*local_nmi);
+        local_nmi->uid    = 0xFFFFFFFF; /* all processors */
+        local_nmi->flags  = cpu_to_le16(0);
+        local_nmi->lint   = 1; /* ACPI_LINT1 */
+    } else {
+        AcpiMadtLocalNmi *local_nmi;
+
+        local_nmi = acpi_data_push(table_data, sizeof *local_nmi);
+        local_nmi->type         = ACPI_APIC_LOCAL_NMI;
+        local_nmi->length       = sizeof(*local_nmi);
+        local_nmi->processor_id = 0xff; /* all processors */
+        local_nmi->flags        = cpu_to_le16(0);
+        local_nmi->lint         = 1; /* ACPI_LINT1 */
+    }
+
+    build_header(linker, table_data,
+                 (void *)(table_data->data + madt_start), "APIC",
+                 table_data->len - madt_start, 1, NULL, NULL);
+}
+
diff --git a/hw/i386/acpi-common.h b/hw/i386/acpi-common.h
new file mode 100644
index 0000000000..9cac18dddf
--- /dev/null
+++ b/hw/i386/acpi-common.h
@@ -0,0 +1,15 @@
+#ifndef HW_I386_ACPI_COMMON_H
+#define HW_I386_ACPI_COMMON_H
+#include "include/hw/acpi/acpi_dev_interface.h"
+
+#include "include/hw/acpi/bios-linker-loader.h"
+#include "include/hw/i386/x86.h"
+
+/* Default IOAPIC ID */
+#define ACPI_BUILD_IOAPIC_ID 0x0
+
+void acpi_build_madt(GArray *table_data, BIOSLinker *linker,
+                     X86MachineState *x86ms, AcpiDeviceIf *adev,
+                     bool has_pci);
+
+#endif
diff --git a/hw/pci-host/i440fx.c b/hw/pci-host/i440fx.c
index 0adbd77553..aefb416c8f 100644
--- a/hw/pci-host/i440fx.c
+++ b/hw/pci-host/i440fx.c
@@ -23,6 +23,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/units.h"
 #include "qemu/range.h"
 #include "hw/i386/pc.h"
 #include "hw/pci/pci.h"
@@ -301,7 +302,7 @@ PCIBus *i440fx_init(const char *host_type, const char *pci_type,
     memory_region_set_enabled(&f->smram_region, true);
 
     /* smram, as seen by SMM CPUs */
-    memory_region_init(&f->smram, OBJECT(d), "smram", 1ull << 32);
+    memory_region_init(&f->smram, OBJECT(d), "smram", 4 * GiB);
     memory_region_set_enabled(&f->smram, true);
     memory_region_init_alias(&f->low_smram, OBJECT(d), "smram-low",
                              f->ram_memory, 0xa0000, 0x20000);
diff --git a/hw/pci-host/prep.c b/hw/pci-host/prep.c
index 1a02e9a670..88e2fc66a9 100644
--- a/hw/pci-host/prep.c
+++ b/hw/pci-host/prep.c
@@ -294,7 +294,7 @@ static void raven_pcihost_initfn(Object *obj)
                              &s->pci_memory, &s->pci_io, 0, TYPE_PCI_BUS);
 
     /* Bus master address space */
-    memory_region_init(&s->bm, obj, "bm-raven", UINT32_MAX);
+    memory_region_init(&s->bm, obj, "bm-raven", 4 * GiB);
     memory_region_init_alias(&s->bm_pci_memory_alias, obj, "bm-pci-memory",
                              &s->pci_memory, 0,
                              memory_region_size(&s->pci_memory));
diff --git a/hw/pci-host/q35.c b/hw/pci-host/q35.c
index 352aeecfa7..b788f17b2c 100644
--- a/hw/pci-host/q35.c
+++ b/hw/pci-host/q35.c
@@ -589,7 +589,7 @@ static void mch_realize(PCIDevice *d, Error **errp)
     memory_region_set_enabled(&mch->open_high_smram, false);
 
     /* smram, as seen by SMM CPUs */
-    memory_region_init(&mch->smram, OBJECT(mch), "smram", 1ull << 32);
+    memory_region_init(&mch->smram, OBJECT(mch), "smram", 4 * GiB);
     memory_region_set_enabled(&mch->smram, true);
     memory_region_init_alias(&mch->low_smram, OBJECT(mch), "smram-low",
                              mch->ram_memory, MCH_HOST_BRIDGE_SMRAM_C_BASE,
diff --git a/hw/pci-host/versatile.c b/hw/pci-host/versatile.c
index cfb9a78ea6..8ddfb8772a 100644
--- a/hw/pci-host/versatile.c
+++ b/hw/pci-host/versatile.c
@@ -8,6 +8,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/units.h"
 #include "hw/sysbus.h"
 #include "migration/vmstate.h"
 #include "hw/irq.h"
@@ -399,8 +400,8 @@ static void pci_vpb_realize(DeviceState *dev, Error **errp)
     pci_map_irq_fn mapfn;
     int i;
 
-    memory_region_init(&s->pci_io_space, OBJECT(s), "pci_io", 1ULL << 32);
-    memory_region_init(&s->pci_mem_space, OBJECT(s), "pci_mem", 1ULL << 32);
+    memory_region_init(&s->pci_io_space, OBJECT(s), "pci_io", 4 * GiB);
+    memory_region_init(&s->pci_mem_space, OBJECT(s), "pci_mem", 4 * GiB);
 
     pci_root_bus_new_inplace(&s->pci_bus, sizeof(s->pci_bus), dev, "pci",
                              &s->pci_mem_space, &s->pci_io_space,
diff --git a/hw/pci/msix.c b/hw/pci/msix.c
index 29187898f2..e6a5559038 100644
--- a/hw/pci/msix.c
+++ b/hw/pci/msix.c
@@ -199,6 +199,9 @@ static const MemoryRegionOps msix_table_mmio_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
     .valid = {
         .min_access_size = 4,
+        .max_access_size = 8,
+    },
+    .impl = {
         .max_access_size = 4,
     },
 };
@@ -227,6 +230,9 @@ static const MemoryRegionOps msix_pba_mmio_ops = {
     .endianness = DEVICE_LITTLE_ENDIAN,
     .valid = {
         .min_access_size = 4,
+        .max_access_size = 8,
+    },
+    .impl = {
         .max_access_size = 4,
     },
 };
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 70c66965f5..a60cf3ae3b 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -1381,6 +1381,8 @@ uint32_t pci_default_read_config(PCIDevice *d,
 {
     uint32_t val = 0;
 
+    assert(address + len <= pci_config_size(d));
+
     if (pci_is_express_downstream_port(d) &&
         ranges_overlap(address, len, d->exp.exp_cap + PCI_EXP_LNKSTA, 2)) {
         pcie_sync_bridge_lnk(d);
@@ -1394,6 +1396,8 @@ void pci_default_write_config(PCIDevice *d, uint32_t addr, uint32_t val_in, int
     int i, was_irq_disabled = pci_irq_disabled(d);
     uint32_t val = val_in;
 
+    assert(addr + l <= pci_config_size(d));
+
     for (i = 0; i < l; val >>= 8, ++i) {
         uint8_t wmask = d->wmask[addr + i];
         uint8_t w1cmask = d->w1cmask[addr + i];
@@ -1772,6 +1776,7 @@ static PciDeviceInfo *qmp_query_pci_device(PCIDevice *dev, PCIBus *bus,
     info->regions = qmp_query_pci_regions(dev);
     info->qdev_id = g_strdup(dev->qdev.id ? dev->qdev.id : "");
 
+    info->irq_pin = dev->config[PCI_INTERRUPT_PIN];
     if (dev->config[PCI_INTERRUPT_PIN] != 0) {
         info->has_irq = true;
         info->irq = dev->config[PCI_INTERRUPT_LINE];
@@ -1887,7 +1892,18 @@ PCIDevice *pci_nic_init_nofail(NICInfo *nd, PCIBus *rootbus,
         if (test_bit(DEVICE_CATEGORY_NETWORK, dc->categories) &&
             dc->user_creatable) {
             const char *name = object_class_get_name(list->data);
-            g_ptr_array_add(pci_nic_models, (gpointer)name);
+            /*
+             * A network device might also be something else than a NIC, see
+             * e.g. the "rocker" device. Thus we have to look for the "netdev"
+             * property, too. Unfortunately, some devices like virtio-net only
+             * create this property during instance_init, so we have to create
+             * a temporary instance here to be able to check it.
+             */
+            Object *obj = object_new_with_class(OBJECT_CLASS(dc));
+            if (object_property_find(obj, "netdev", NULL)) {
+                g_ptr_array_add(pci_nic_models, (gpointer)name);
+            }
+            object_unref(obj);
         }
         next = list->next;
         g_slist_free_1(list);
diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index 97967d12eb..3789c17edc 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -30,6 +30,7 @@
  */
 
 #include "qemu/osdep.h"
+#include "qemu/units.h"
 #include "hw/pci/pci_bridge.h"
 #include "hw/pci/pci_bus.h"
 #include "qemu/module.h"
@@ -381,7 +382,7 @@ void pci_bridge_initfn(PCIDevice *dev, const char *typename)
     memory_region_init(&br->address_space_mem, OBJECT(br), "pci_bridge_pci", UINT64_MAX);
     sec_bus->address_space_io = &br->address_space_io;
     memory_region_init(&br->address_space_io, OBJECT(br), "pci_bridge_io",
-                       UINT32_MAX);
+                       4 * GiB);
     br->windows = pci_bridge_region_init(br);
     QLIST_INIT(&sec_bus->child);
     QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
@@ -422,14 +423,14 @@ int pci_bridge_qemu_reserve_cap_init(PCIDevice *dev, int cap_offset,
     }
 
     if (res_reserve.mem_non_pref != (uint64_t)-1 &&
-        res_reserve.mem_non_pref >= (1ULL << 32)) {
+        res_reserve.mem_non_pref >= 4 * GiB) {
         error_setg(errp,
                    "PCI resource reserve cap: mem-reserve must be less than 4G");
         return -EINVAL;
     }
 
     if (res_reserve.mem_pref_32 != (uint64_t)-1 &&
-        res_reserve.mem_pref_32 >= (1ULL << 32)) {
+        res_reserve.mem_pref_32 >= 4 * GiB) {
         error_setg(errp,
                    "PCI resource reserve cap: pref32-reserve  must be less than 4G");
         return -EINVAL;
diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c
index f50e10b8fb..5b9c022d91 100644
--- a/hw/pci/pcie.c
+++ b/hw/pci/pcie.c
@@ -407,6 +407,17 @@ static void pcie_cap_slot_plug_common(PCIDevice *hotplug_dev, DeviceState *dev,
 void pcie_cap_slot_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
                                Error **errp)
 {
+    PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
+    uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
+    uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP);
+
+    /* Check if hot-plug is disabled on the slot */
+    if (dev->hotplugged && (sltcap & PCI_EXP_SLTCAP_HPC) == 0) {
+        error_setg(errp, "Hot-plug failed: unsupported by the port device '%s'",
+                         DEVICE(hotplug_pdev)->id);
+        return;
+    }
+
     pcie_cap_slot_plug_common(PCI_DEVICE(hotplug_dev), dev, errp);
 }
 
@@ -415,7 +426,6 @@ void pcie_cap_slot_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
 {
     PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev);
     uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap;
-    uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP);
     PCIDevice *pci_dev = PCI_DEVICE(dev);
 
     /* Don't send event when device is enabled during qemu machine creation:
@@ -431,13 +441,6 @@ void pcie_cap_slot_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev,
         return;
     }
 
-    /* Check if hot-plug is disabled on the slot */
-    if ((sltcap & PCI_EXP_SLTCAP_HPC) == 0) {
-        error_setg(errp, "Hot-plug failed: unsupported by the port device '%s'",
-                         DEVICE(hotplug_pdev)->id);
-        return;
-    }
-
     /* To enable multifunction hot-plug, we just ensure the function
      * 0 added last. When function 0 is added, we set the sltsta and
      * inform OS via event notification.
diff --git a/hw/rtc/mc146818rtc.c b/hw/rtc/mc146818rtc.c
index 9c30cbdcd7..1e9fa0f33f 100644
--- a/hw/rtc/mc146818rtc.c
+++ b/hw/rtc/mc146818rtc.c
@@ -27,6 +27,7 @@
 #include "qemu/cutils.h"
 #include "qemu/module.h"
 #include "qemu/bcd.h"
+#include "hw/acpi/aml-build.h"
 #include "hw/irq.h"
 #include "hw/qdev-properties.h"
 #include "qemu/timer.h"
@@ -1007,13 +1008,36 @@ static void rtc_resetdev(DeviceState *d)
     }
 }
 
+static void rtc_build_aml(ISADevice *isadev, Aml *scope)
+{
+    Aml *dev;
+    Aml *crs;
+
+    /*
+     * Reserving 8 io ports here, following what physical hardware
+     * does, even though qemu only responds to the first two ports.
+     */
+    crs = aml_resource_template();
+    aml_append(crs, aml_io(AML_DECODE16, RTC_ISA_BASE, RTC_ISA_BASE,
+                           0x01, 0x08));
+    aml_append(crs, aml_irq_no_flags(RTC_ISA_IRQ));
+
+    dev = aml_device("RTC");
+    aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0B00")));
+    aml_append(dev, aml_name_decl("_CRS", crs));
+
+    aml_append(scope, dev);
+}
+
 static void rtc_class_initfn(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
+    ISADeviceClass *isa = ISA_DEVICE_CLASS(klass);
 
     dc->realize = rtc_realizefn;
     dc->reset = rtc_resetdev;
     dc->vmsd = &vmstate_rtc;
+    isa->build_aml = rtc_build_aml;
     device_class_set_props(dc, mc146818rtc_properties);
 }
 
diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index 4e4d39a0a4..13e75f171f 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -17,10 +17,12 @@ obj-$(CONFIG_VIRTIO_PMEM) += virtio-pmem.o
 common-obj-$(call land,$(CONFIG_VIRTIO_PMEM),$(CONFIG_VIRTIO_PCI)) += virtio-pmem-pci.o
 obj-$(call land,$(CONFIG_VHOST_USER_FS),$(CONFIG_VIRTIO_PCI)) += vhost-user-fs-pci.o
 obj-$(CONFIG_VIRTIO_IOMMU) += virtio-iommu.o
-obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock.o
+obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock-common.o vhost-vsock.o
+obj-$(CONFIG_VHOST_USER_VSOCK) += vhost-vsock-common.o vhost-user-vsock.o
 
 ifeq ($(CONFIG_VIRTIO_PCI),y)
 obj-$(CONFIG_VHOST_VSOCK) += vhost-vsock-pci.o
+obj-$(CONFIG_VHOST_USER_VSOCK) += vhost-user-vsock-pci.o
 obj-$(CONFIG_VHOST_USER_BLK) += vhost-user-blk-pci.o
 obj-$(CONFIG_VHOST_USER_INPUT) += vhost-user-input-pci.o
 obj-$(CONFIG_VHOST_USER_SCSI) += vhost-user-scsi-pci.o
diff --git a/hw/virtio/vhost-user-vsock-pci.c b/hw/virtio/vhost-user-vsock-pci.c
new file mode 100644
index 0000000000..0a6847e6fc
--- /dev/null
+++ b/hw/virtio/vhost-user-vsock-pci.c
@@ -0,0 +1,84 @@
+/*
+ * Vhost-user vsock PCI Bindings
+ *
+ * Copyright 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include "virtio-pci.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/vhost-user-vsock.h"
+
+typedef struct VHostUserVSockPCI VHostUserVSockPCI;
+
+/*
+ * vhost-user-vsock-pci: This extends VirtioPCIProxy.
+ */
+#define TYPE_VHOST_USER_VSOCK_PCI "vhost-user-vsock-pci-base"
+#define VHOST_USER_VSOCK_PCI(obj) \
+        OBJECT_CHECK(VHostUserVSockPCI, (obj), TYPE_VHOST_USER_VSOCK_PCI)
+
+struct VHostUserVSockPCI {
+    VirtIOPCIProxy parent_obj;
+    VHostUserVSock vdev;
+};
+
+/* vhost-user-vsock-pci */
+
+static Property vhost_user_vsock_pci_properties[] = {
+    DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors, 3),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vhost_user_vsock_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
+{
+    VHostUserVSockPCI *dev = VHOST_USER_VSOCK_PCI(vpci_dev);
+    DeviceState *vdev = DEVICE(&dev->vdev);
+
+    qdev_set_parent_bus(vdev, BUS(&vpci_dev->bus));
+    object_property_set_bool(OBJECT(vdev), true, "realized", errp);
+}
+
+static void vhost_user_vsock_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);
+    k->realize = vhost_user_vsock_pci_realize;
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+    device_class_set_props(dc, vhost_user_vsock_pci_properties);
+    pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+    pcidev_k->device_id = PCI_DEVICE_ID_VIRTIO_VSOCK;
+    pcidev_k->revision = 0x00;
+    pcidev_k->class_id = PCI_CLASS_COMMUNICATION_OTHER;
+}
+
+static void vhost_user_vsock_pci_instance_init(Object *obj)
+{
+    VHostUserVSockPCI *dev = VHOST_USER_VSOCK_PCI(obj);
+
+    virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
+                                TYPE_VHOST_USER_VSOCK);
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_user_vsock_pci_info = {
+    .base_name             = TYPE_VHOST_USER_VSOCK_PCI,
+    .generic_name          = "vhost-user-vsock-pci",
+    .transitional_name     = "vhost-user-vsock-pci-transitional",
+    .non_transitional_name = "vhost-user-vsock-pci-non-transitional",
+    .instance_size = sizeof(VHostUserVSockPCI),
+    .instance_init = vhost_user_vsock_pci_instance_init,
+    .class_init    = vhost_user_vsock_pci_class_init,
+};
+
+static void virtio_pci_vhost_register(void)
+{
+    virtio_pci_types_register(&vhost_user_vsock_pci_info);
+}
+
+type_init(virtio_pci_vhost_register)
diff --git a/hw/virtio/vhost-user-vsock.c b/hw/virtio/vhost-user-vsock.c
new file mode 100644
index 0000000000..3534a39d62
--- /dev/null
+++ b/hw/virtio/vhost-user-vsock.c
@@ -0,0 +1,181 @@
+/*
+ * Vhost-user vsock virtio device
+ *
+ * Copyright 2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include "qapi/error.h"
+#include "qemu/error-report.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/vhost-user-vsock.h"
+
+static const int user_feature_bits[] = {
+    VIRTIO_F_VERSION_1,
+    VIRTIO_RING_F_INDIRECT_DESC,
+    VIRTIO_RING_F_EVENT_IDX,
+    VIRTIO_F_NOTIFY_ON_EMPTY,
+    VHOST_INVALID_FEATURE_BIT
+};
+
+static void vuv_get_config(VirtIODevice *vdev, uint8_t *config)
+{
+    VHostUserVSock *vsock = VHOST_USER_VSOCK(vdev);
+
+    memcpy(config, &vsock->vsockcfg, sizeof(struct virtio_vsock_config));
+}
+
+static int vuv_handle_config_change(struct vhost_dev *dev)
+{
+    VHostUserVSock *vsock = VHOST_USER_VSOCK(dev->vdev);
+    int ret = vhost_dev_get_config(dev, (uint8_t *)&vsock->vsockcfg,
+                                   sizeof(struct virtio_vsock_config));
+    if (ret < 0) {
+        error_report("get config space failed");
+        return -1;
+    }
+
+    virtio_notify_config(dev->vdev);
+
+    return 0;
+}
+
+const VhostDevConfigOps vsock_ops = {
+    .vhost_dev_config_notifier = vuv_handle_config_change,
+};
+
+static void vuv_set_status(VirtIODevice *vdev, uint8_t status)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+    bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
+
+    if (!vdev->vm_running) {
+        should_start = false;
+    }
+
+    if (vvc->vhost_dev.started == should_start) {
+        return;
+    }
+
+    if (should_start) {
+        int ret = vhost_vsock_common_start(vdev);
+        if (ret < 0) {
+            return;
+        }
+    } else {
+        vhost_vsock_common_stop(vdev);
+    }
+}
+
+static uint64_t vuv_get_features(VirtIODevice *vdev,
+                                 uint64_t features,
+                                 Error **errp)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+
+    return vhost_get_features(&vvc->vhost_dev, user_feature_bits, features);
+}
+
+static const VMStateDescription vuv_vmstate = {
+    .name = "vhost-user-vsock",
+    .unmigratable = 1,
+};
+
+static void vuv_device_realize(DeviceState *dev, Error **errp)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev);
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserVSock *vsock = VHOST_USER_VSOCK(dev);
+    int ret;
+
+    if (!vsock->conf.chardev.chr) {
+        error_setg(errp, "missing chardev");
+        return;
+    }
+
+    if (!vhost_user_init(&vsock->vhost_user, &vsock->conf.chardev, errp)) {
+        return;
+    }
+
+    vhost_vsock_common_realize(vdev, "vhost-user-vsock");
+
+    vhost_dev_set_config_notifier(&vvc->vhost_dev, &vsock_ops);
+
+    ret = vhost_dev_init(&vvc->vhost_dev, &vsock->vhost_user,
+                         VHOST_BACKEND_TYPE_USER, 0);
+    if (ret < 0) {
+        error_setg_errno(errp, -ret, "vhost_dev_init failed");
+        goto err_virtio;
+    }
+
+    ret = vhost_dev_get_config(&vvc->vhost_dev, (uint8_t *)&vsock->vsockcfg,
+                               sizeof(struct virtio_vsock_config));
+    if (ret < 0) {
+        error_setg_errno(errp, -ret, "get config space failed");
+        goto err_vhost_dev;
+    }
+
+    return;
+
+err_vhost_dev:
+    vhost_dev_cleanup(&vvc->vhost_dev);
+err_virtio:
+    vhost_vsock_common_unrealize(vdev);
+    vhost_user_cleanup(&vsock->vhost_user);
+    return;
+}
+
+static void vuv_device_unrealize(DeviceState *dev)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev);
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserVSock *vsock = VHOST_USER_VSOCK(dev);
+
+    /* This will stop vhost backend if appropriate. */
+    vuv_set_status(vdev, 0);
+
+    vhost_dev_cleanup(&vvc->vhost_dev);
+
+    vhost_vsock_common_unrealize(vdev);
+
+    vhost_user_cleanup(&vsock->vhost_user);
+
+}
+
+static Property vuv_properties[] = {
+    DEFINE_PROP_CHR("chardev", VHostUserVSock, conf.chardev),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vuv_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+    device_class_set_props(dc, vuv_properties);
+    dc->vmsd = &vuv_vmstate;
+    vdc->realize = vuv_device_realize;
+    vdc->unrealize = vuv_device_unrealize;
+    vdc->get_features = vuv_get_features;
+    vdc->get_config = vuv_get_config;
+    vdc->set_status = vuv_set_status;
+}
+
+static const TypeInfo vuv_info = {
+    .name = TYPE_VHOST_USER_VSOCK,
+    .parent = TYPE_VHOST_VSOCK_COMMON,
+    .instance_size = sizeof(VHostUserVSock),
+    .class_init = vuv_class_init,
+};
+
+static void vuv_register_types(void)
+{
+    type_register_static(&vuv_info);
+}
+
+type_init(vuv_register_types)
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index ec21e8fbe8..4d6cd4e58a 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -35,11 +35,29 @@
 #include <linux/userfaultfd.h>
 #endif
 
-#define VHOST_MEMORY_MAX_NREGIONS    8
+#define VHOST_MEMORY_BASELINE_NREGIONS    8
 #define VHOST_USER_F_PROTOCOL_FEATURES 30
 #define VHOST_USER_SLAVE_MAX_FDS     8
 
 /*
+ * Set maximum number of RAM slots supported to
+ * the maximum number supported by the target
+ * hardware plaform.
+ */
+#if defined(TARGET_X86) || defined(TARGET_X86_64) || \
+    defined(TARGET_ARM) || defined(TARGET_ARM_64)
+#include "hw/acpi/acpi.h"
+#define VHOST_USER_MAX_RAM_SLOTS ACPI_MAX_RAM_SLOTS
+
+#elif defined(TARGET_PPC) || defined(TARGET_PPC_64)
+#include "hw/ppc/spapr.h"
+#define VHOST_USER_MAX_RAM_SLOTS SPAPR_MAX_RAM_SLOTS
+
+#else
+#define VHOST_USER_MAX_RAM_SLOTS 512
+#endif
+
+/*
  * Maximum size of virtio device config space
  */
 #define VHOST_USER_MAX_CONFIG_SIZE 256
@@ -59,6 +77,8 @@ enum VhostUserProtocolFeature {
     VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
     VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
     VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
+    /* Feature 14 reserved for VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS. */
+    VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
     VHOST_USER_PROTOCOL_F_MAX
 };
 
@@ -100,6 +120,10 @@ typedef enum VhostUserRequest {
     VHOST_USER_SET_INFLIGHT_FD = 32,
     VHOST_USER_GPU_SET_SOCKET = 33,
     VHOST_USER_RESET_DEVICE = 34,
+    /* Message number 35 reserved for VHOST_USER_VRING_KICK. */
+    VHOST_USER_GET_MAX_MEM_SLOTS = 36,
+    VHOST_USER_ADD_MEM_REG = 37,
+    VHOST_USER_REM_MEM_REG = 38,
     VHOST_USER_MAX
 } VhostUserRequest;
 
@@ -121,9 +145,14 @@ typedef struct VhostUserMemoryRegion {
 typedef struct VhostUserMemory {
     uint32_t nregions;
     uint32_t padding;
-    VhostUserMemoryRegion regions[VHOST_MEMORY_MAX_NREGIONS];
+    VhostUserMemoryRegion regions[VHOST_MEMORY_BASELINE_NREGIONS];
 } VhostUserMemory;
 
+typedef struct VhostUserMemRegMsg {
+    uint32_t padding;
+    VhostUserMemoryRegion region;
+} VhostUserMemRegMsg;
+
 typedef struct VhostUserLog {
     uint64_t mmap_size;
     uint64_t mmap_offset;
@@ -182,6 +211,7 @@ typedef union {
         struct vhost_vring_state state;
         struct vhost_vring_addr addr;
         VhostUserMemory memory;
+        VhostUserMemRegMsg mem_reg;
         VhostUserLog log;
         struct vhost_iotlb_msg iotlb;
         VhostUserConfig config;
@@ -210,7 +240,7 @@ struct vhost_user {
     int slave_fd;
     NotifierWithReturn postcopy_notifier;
     struct PostCopyFD  postcopy_fd;
-    uint64_t           postcopy_client_bases[VHOST_MEMORY_MAX_NREGIONS];
+    uint64_t           postcopy_client_bases[VHOST_USER_MAX_RAM_SLOTS];
     /* Length of the region_rb and region_rb_offset arrays */
     size_t             region_rb_len;
     /* RAMBlock associated with a given region */
@@ -222,6 +252,16 @@ struct vhost_user {
 
     /* True once we've entered postcopy_listen */
     bool               postcopy_listen;
+
+    /* Our current regions */
+    int num_shadow_regions;
+    struct vhost_memory_region shadow_regions[VHOST_USER_MAX_RAM_SLOTS];
+};
+
+struct scrub_regions {
+    struct vhost_memory_region *region;
+    int reg_idx;
+    int fd_idx;
 };
 
 static bool ioeventfd_enabled(void)
@@ -370,7 +410,7 @@ int vhost_user_gpu_set_socket(struct vhost_dev *dev, int fd)
 static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
                                    struct vhost_log *log)
 {
-    int fds[VHOST_MEMORY_MAX_NREGIONS];
+    int fds[VHOST_USER_MAX_RAM_SLOTS];
     size_t fd_num = 0;
     bool shmfd = virtio_has_feature(dev->protocol_features,
                                     VHOST_USER_PROTOCOL_F_LOG_SHMFD);
@@ -407,6 +447,27 @@ static int vhost_user_set_log_base(struct vhost_dev *dev, uint64_t base,
     return 0;
 }
 
+static MemoryRegion *vhost_user_get_mr_data(uint64_t addr, ram_addr_t *offset,
+                                            int *fd)
+{
+    MemoryRegion *mr;
+
+    assert((uintptr_t)addr == addr);
+    mr = memory_region_from_host((void *)(uintptr_t)addr, offset);
+    *fd = memory_region_get_fd(mr);
+
+    return mr;
+}
+
+static void vhost_user_fill_msg_region(VhostUserMemoryRegion *dst,
+                                       struct vhost_memory_region *src)
+{
+    assert(src != NULL && dst != NULL);
+    dst->userspace_addr = src->userspace_addr;
+    dst->memory_size = src->memory_size;
+    dst->guest_phys_addr = src->guest_phys_addr;
+}
+
 static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u,
                                              struct vhost_dev *dev,
                                              VhostUserMsg *msg,
@@ -417,19 +478,17 @@ static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u,
     ram_addr_t offset;
     MemoryRegion *mr;
     struct vhost_memory_region *reg;
+    VhostUserMemoryRegion region_buffer;
 
     msg->hdr.request = VHOST_USER_SET_MEM_TABLE;
 
     for (i = 0; i < dev->mem->nregions; ++i) {
         reg = dev->mem->regions + i;
 
-        assert((uintptr_t)reg->userspace_addr == reg->userspace_addr);
-        mr = memory_region_from_host((void *)(uintptr_t)reg->userspace_addr,
-                                     &offset);
-        fd = memory_region_get_fd(mr);
+        mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
         if (fd > 0) {
             if (track_ramblocks) {
-                assert(*fd_num < VHOST_MEMORY_MAX_NREGIONS);
+                assert(*fd_num < VHOST_MEMORY_BASELINE_NREGIONS);
                 trace_vhost_user_set_mem_table_withfd(*fd_num, mr->name,
                                                       reg->memory_size,
                                                       reg->guest_phys_addr,
@@ -437,16 +496,12 @@ static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u,
                                                       offset);
                 u->region_rb_offset[i] = offset;
                 u->region_rb[i] = mr->ram_block;
-            } else if (*fd_num == VHOST_MEMORY_MAX_NREGIONS) {
+            } else if (*fd_num == VHOST_MEMORY_BASELINE_NREGIONS) {
                 error_report("Failed preparing vhost-user memory table msg");
                 return -1;
             }
-            msg->payload.memory.regions[*fd_num].userspace_addr =
-                reg->userspace_addr;
-            msg->payload.memory.regions[*fd_num].memory_size =
-                reg->memory_size;
-            msg->payload.memory.regions[*fd_num].guest_phys_addr =
-                reg->guest_phys_addr;
+            vhost_user_fill_msg_region(&region_buffer, reg);
+            msg->payload.memory.regions[*fd_num] = region_buffer;
             msg->payload.memory.regions[*fd_num].mmap_offset = offset;
             fds[(*fd_num)++] = fd;
         } else if (track_ramblocks) {
@@ -470,11 +525,335 @@ static int vhost_user_fill_set_mem_table_msg(struct vhost_user *u,
     return 1;
 }
 
+static inline bool reg_equal(struct vhost_memory_region *shadow_reg,
+                             struct vhost_memory_region *vdev_reg)
+{
+    return shadow_reg->guest_phys_addr == vdev_reg->guest_phys_addr &&
+        shadow_reg->userspace_addr == vdev_reg->userspace_addr &&
+        shadow_reg->memory_size == vdev_reg->memory_size;
+}
+
+static void scrub_shadow_regions(struct vhost_dev *dev,
+                                 struct scrub_regions *add_reg,
+                                 int *nr_add_reg,
+                                 struct scrub_regions *rem_reg,
+                                 int *nr_rem_reg, uint64_t *shadow_pcb,
+                                 bool track_ramblocks)
+{
+    struct vhost_user *u = dev->opaque;
+    bool found[VHOST_USER_MAX_RAM_SLOTS] = {};
+    struct vhost_memory_region *reg, *shadow_reg;
+    int i, j, fd, add_idx = 0, rm_idx = 0, fd_num = 0;
+    ram_addr_t offset;
+    MemoryRegion *mr;
+    bool matching;
+
+    /*
+     * Find memory regions present in our shadow state which are not in
+     * the device's current memory state.
+     *
+     * Mark regions in both the shadow and device state as "found".
+     */
+    for (i = 0; i < u->num_shadow_regions; i++) {
+        shadow_reg = &u->shadow_regions[i];
+        matching = false;
+
+        for (j = 0; j < dev->mem->nregions; j++) {
+            reg = &dev->mem->regions[j];
+
+            mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
+
+            if (reg_equal(shadow_reg, reg)) {
+                matching = true;
+                found[j] = true;
+                if (track_ramblocks) {
+                    /*
+                     * Reset postcopy client bases, region_rb, and
+                     * region_rb_offset in case regions are removed.
+                     */
+                    if (fd > 0) {
+                        u->region_rb_offset[j] = offset;
+                        u->region_rb[j] = mr->ram_block;
+                        shadow_pcb[j] = u->postcopy_client_bases[i];
+                    } else {
+                        u->region_rb_offset[j] = 0;
+                        u->region_rb[j] = NULL;
+                    }
+                }
+                break;
+            }
+        }
+
+        /*
+         * If the region was not found in the current device memory state
+         * create an entry for it in the removed list.
+         */
+        if (!matching) {
+            rem_reg[rm_idx].region = shadow_reg;
+            rem_reg[rm_idx++].reg_idx = i;
+        }
+    }
+
+    /*
+     * For regions not marked "found", create entries in the added list.
+     *
+     * Note their indexes in the device memory state and the indexes of their
+     * file descriptors.
+     */
+    for (i = 0; i < dev->mem->nregions; i++) {
+        reg = &dev->mem->regions[i];
+        mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
+        if (fd > 0) {
+            ++fd_num;
+        }
+
+        /*
+         * If the region was in both the shadow and device state we don't
+         * need to send a VHOST_USER_ADD_MEM_REG message for it.
+         */
+        if (found[i]) {
+            continue;
+        }
+
+        add_reg[add_idx].region = reg;
+        add_reg[add_idx].reg_idx = i;
+        add_reg[add_idx++].fd_idx = fd_num;
+    }
+    *nr_rem_reg = rm_idx;
+    *nr_add_reg = add_idx;
+
+    return;
+}
+
+static int send_remove_regions(struct vhost_dev *dev,
+                               struct scrub_regions *remove_reg,
+                               int nr_rem_reg, VhostUserMsg *msg,
+                               bool reply_supported)
+{
+    struct vhost_user *u = dev->opaque;
+    struct vhost_memory_region *shadow_reg;
+    int i, fd, shadow_reg_idx, ret;
+    ram_addr_t offset;
+    VhostUserMemoryRegion region_buffer;
+
+    /*
+     * The regions in remove_reg appear in the same order they do in the
+     * shadow table. Therefore we can minimize memory copies by iterating
+     * through remove_reg backwards.
+     */
+    for (i = nr_rem_reg - 1; i >= 0; i--) {
+        shadow_reg = remove_reg[i].region;
+        shadow_reg_idx = remove_reg[i].reg_idx;
+
+        vhost_user_get_mr_data(shadow_reg->userspace_addr, &offset, &fd);
+
+        if (fd > 0) {
+            msg->hdr.request = VHOST_USER_REM_MEM_REG;
+            vhost_user_fill_msg_region(&region_buffer, shadow_reg);
+            msg->payload.mem_reg.region = region_buffer;
+
+            if (vhost_user_write(dev, msg, &fd, 1) < 0) {
+                return -1;
+            }
+
+            if (reply_supported) {
+                ret = process_message_reply(dev, msg);
+                if (ret) {
+                    return ret;
+                }
+            }
+        }
+
+        /*
+         * At this point we know the backend has unmapped the region. It is now
+         * safe to remove it from the shadow table.
+         */
+        memmove(&u->shadow_regions[shadow_reg_idx],
+                &u->shadow_regions[shadow_reg_idx + 1],
+                sizeof(struct vhost_memory_region) *
+                (u->num_shadow_regions - shadow_reg_idx));
+        u->num_shadow_regions--;
+    }
+
+    return 0;
+}
+
+static int send_add_regions(struct vhost_dev *dev,
+                            struct scrub_regions *add_reg, int nr_add_reg,
+                            VhostUserMsg *msg, uint64_t *shadow_pcb,
+                            bool reply_supported, bool track_ramblocks)
+{
+    struct vhost_user *u = dev->opaque;
+    int i, fd, ret, reg_idx, reg_fd_idx;
+    struct vhost_memory_region *reg;
+    MemoryRegion *mr;
+    ram_addr_t offset;
+    VhostUserMsg msg_reply;
+    VhostUserMemoryRegion region_buffer;
+
+    for (i = 0; i < nr_add_reg; i++) {
+        reg = add_reg[i].region;
+        reg_idx = add_reg[i].reg_idx;
+        reg_fd_idx = add_reg[i].fd_idx;
+
+        mr = vhost_user_get_mr_data(reg->userspace_addr, &offset, &fd);
+
+        if (fd > 0) {
+            if (track_ramblocks) {
+                trace_vhost_user_set_mem_table_withfd(reg_fd_idx, mr->name,
+                                                      reg->memory_size,
+                                                      reg->guest_phys_addr,
+                                                      reg->userspace_addr,
+                                                      offset);
+                u->region_rb_offset[reg_idx] = offset;
+                u->region_rb[reg_idx] = mr->ram_block;
+            }
+            msg->hdr.request = VHOST_USER_ADD_MEM_REG;
+            vhost_user_fill_msg_region(&region_buffer, reg);
+            msg->payload.mem_reg.region = region_buffer;
+            msg->payload.mem_reg.region.mmap_offset = offset;
+
+            if (vhost_user_write(dev, msg, &fd, 1) < 0) {
+                return -1;
+            }
+
+            if (track_ramblocks) {
+                uint64_t reply_gpa;
+
+                if (vhost_user_read(dev, &msg_reply) < 0) {
+                    return -1;
+                }
+
+                reply_gpa = msg_reply.payload.mem_reg.region.guest_phys_addr;
+
+                if (msg_reply.hdr.request != VHOST_USER_ADD_MEM_REG) {
+                    error_report("%s: Received unexpected msg type."
+                                 "Expected %d received %d", __func__,
+                                 VHOST_USER_ADD_MEM_REG,
+                                 msg_reply.hdr.request);
+                    return -1;
+                }
+
+                /*
+                 * We're using the same structure, just reusing one of the
+                 * fields, so it should be the same size.
+                 */
+                if (msg_reply.hdr.size != msg->hdr.size) {
+                    error_report("%s: Unexpected size for postcopy reply "
+                                 "%d vs %d", __func__, msg_reply.hdr.size,
+                                 msg->hdr.size);
+                    return -1;
+                }
+
+                /* Get the postcopy client base from the backend's reply. */
+                if (reply_gpa == dev->mem->regions[reg_idx].guest_phys_addr) {
+                    shadow_pcb[reg_idx] =
+                        msg_reply.payload.mem_reg.region.userspace_addr;
+                    trace_vhost_user_set_mem_table_postcopy(
+                        msg_reply.payload.mem_reg.region.userspace_addr,
+                        msg->payload.mem_reg.region.userspace_addr,
+                        reg_fd_idx, reg_idx);
+                } else {
+                    error_report("%s: invalid postcopy reply for region. "
+                                 "Got guest physical address %" PRIX64 ", expected "
+                                 "%" PRIX64, __func__, reply_gpa,
+                                 dev->mem->regions[reg_idx].guest_phys_addr);
+                    return -1;
+                }
+            } else if (reply_supported) {
+                ret = process_message_reply(dev, msg);
+                if (ret) {
+                    return ret;
+                }
+            }
+        } else if (track_ramblocks) {
+            u->region_rb_offset[reg_idx] = 0;
+            u->region_rb[reg_idx] = NULL;
+        }
+
+        /*
+         * At this point, we know the backend has mapped in the new
+         * region, if the region has a valid file descriptor.
+         *
+         * The region should now be added to the shadow table.
+         */
+        u->shadow_regions[u->num_shadow_regions].guest_phys_addr =
+            reg->guest_phys_addr;
+        u->shadow_regions[u->num_shadow_regions].userspace_addr =
+            reg->userspace_addr;
+        u->shadow_regions[u->num_shadow_regions].memory_size =
+            reg->memory_size;
+        u->num_shadow_regions++;
+    }
+
+    return 0;
+}
+
+static int vhost_user_add_remove_regions(struct vhost_dev *dev,
+                                         VhostUserMsg *msg,
+                                         bool reply_supported,
+                                         bool track_ramblocks)
+{
+    struct vhost_user *u = dev->opaque;
+    struct scrub_regions add_reg[VHOST_USER_MAX_RAM_SLOTS];
+    struct scrub_regions rem_reg[VHOST_USER_MAX_RAM_SLOTS];
+    uint64_t shadow_pcb[VHOST_USER_MAX_RAM_SLOTS] = {};
+    int nr_add_reg, nr_rem_reg;
+
+    msg->hdr.size = sizeof(msg->payload.mem_reg.padding) +
+        sizeof(VhostUserMemoryRegion);
+
+    /* Find the regions which need to be removed or added. */
+    scrub_shadow_regions(dev, add_reg, &nr_add_reg, rem_reg, &nr_rem_reg,
+                         shadow_pcb, track_ramblocks);
+
+    if (nr_rem_reg && send_remove_regions(dev, rem_reg, nr_rem_reg, msg,
+                reply_supported) < 0)
+    {
+        goto err;
+    }
+
+    if (nr_add_reg && send_add_regions(dev, add_reg, nr_add_reg, msg,
+                shadow_pcb, reply_supported, track_ramblocks) < 0)
+    {
+        goto err;
+    }
+
+    if (track_ramblocks) {
+        memcpy(u->postcopy_client_bases, shadow_pcb,
+               sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
+        /*
+         * Now we've registered this with the postcopy code, we ack to the
+         * client, because now we're in the position to be able to deal with
+         * any faults it generates.
+         */
+        /* TODO: Use this for failure cases as well with a bad value. */
+        msg->hdr.size = sizeof(msg->payload.u64);
+        msg->payload.u64 = 0; /* OK */
+
+        if (vhost_user_write(dev, msg, NULL, 0) < 0) {
+            return -1;
+        }
+    }
+
+    return 0;
+
+err:
+    if (track_ramblocks) {
+        memcpy(u->postcopy_client_bases, shadow_pcb,
+               sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
+    }
+
+    return -1;
+}
+
 static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev,
-                                             struct vhost_memory *mem)
+                                             struct vhost_memory *mem,
+                                             bool reply_supported,
+                                             bool config_mem_slots)
 {
     struct vhost_user *u = dev->opaque;
-    int fds[VHOST_MEMORY_MAX_NREGIONS];
+    int fds[VHOST_MEMORY_BASELINE_NREGIONS];
     size_t fd_num = 0;
     VhostUserMsg msg_reply;
     int region_i, msg_i;
@@ -494,71 +873,84 @@ static int vhost_user_set_mem_table_postcopy(struct vhost_dev *dev,
         u->region_rb_len = dev->mem->nregions;
     }
 
-    if (vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
+    if (config_mem_slots) {
+        if (vhost_user_add_remove_regions(dev, &msg, reply_supported,
                                           true) < 0) {
-        return -1;
-    }
+            return -1;
+        }
+    } else {
+        if (vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
+                                              true) < 0) {
+            return -1;
+        }
 
-    if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
-        return -1;
-    }
+        if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
+            return -1;
+        }
 
-    if (vhost_user_read(dev, &msg_reply) < 0) {
-        return -1;
-    }
+        if (vhost_user_read(dev, &msg_reply) < 0) {
+            return -1;
+        }
 
-    if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) {
-        error_report("%s: Received unexpected msg type."
-                     "Expected %d received %d", __func__,
-                     VHOST_USER_SET_MEM_TABLE, msg_reply.hdr.request);
-        return -1;
-    }
-    /* We're using the same structure, just reusing one of the
-     * fields, so it should be the same size.
-     */
-    if (msg_reply.hdr.size != msg.hdr.size) {
-        error_report("%s: Unexpected size for postcopy reply "
-                     "%d vs %d", __func__, msg_reply.hdr.size, msg.hdr.size);
-        return -1;
-    }
-
-    memset(u->postcopy_client_bases, 0,
-           sizeof(uint64_t) * VHOST_MEMORY_MAX_NREGIONS);
-
-    /* They're in the same order as the regions that were sent
-     * but some of the regions were skipped (above) if they
-     * didn't have fd's
-    */
-    for (msg_i = 0, region_i = 0;
-         region_i < dev->mem->nregions;
-        region_i++) {
-        if (msg_i < fd_num &&
-            msg_reply.payload.memory.regions[msg_i].guest_phys_addr ==
-            dev->mem->regions[region_i].guest_phys_addr) {
-            u->postcopy_client_bases[region_i] =
-                msg_reply.payload.memory.regions[msg_i].userspace_addr;
-            trace_vhost_user_set_mem_table_postcopy(
-                msg_reply.payload.memory.regions[msg_i].userspace_addr,
-                msg.payload.memory.regions[msg_i].userspace_addr,
-                msg_i, region_i);
-            msg_i++;
+        if (msg_reply.hdr.request != VHOST_USER_SET_MEM_TABLE) {
+            error_report("%s: Received unexpected msg type."
+                         "Expected %d received %d", __func__,
+                         VHOST_USER_SET_MEM_TABLE, msg_reply.hdr.request);
+            return -1;
+        }
+
+        /*
+         * We're using the same structure, just reusing one of the
+         * fields, so it should be the same size.
+         */
+        if (msg_reply.hdr.size != msg.hdr.size) {
+            error_report("%s: Unexpected size for postcopy reply "
+                         "%d vs %d", __func__, msg_reply.hdr.size,
+                         msg.hdr.size);
+            return -1;
+        }
+
+        memset(u->postcopy_client_bases, 0,
+               sizeof(uint64_t) * VHOST_USER_MAX_RAM_SLOTS);
+
+        /*
+         * They're in the same order as the regions that were sent
+         * but some of the regions were skipped (above) if they
+         * didn't have fd's
+         */
+        for (msg_i = 0, region_i = 0;
+             region_i < dev->mem->nregions;
+             region_i++) {
+            if (msg_i < fd_num &&
+                msg_reply.payload.memory.regions[msg_i].guest_phys_addr ==
+                dev->mem->regions[region_i].guest_phys_addr) {
+                u->postcopy_client_bases[region_i] =
+                    msg_reply.payload.memory.regions[msg_i].userspace_addr;
+                trace_vhost_user_set_mem_table_postcopy(
+                    msg_reply.payload.memory.regions[msg_i].userspace_addr,
+                    msg.payload.memory.regions[msg_i].userspace_addr,
+                    msg_i, region_i);
+                msg_i++;
+            }
+        }
+        if (msg_i != fd_num) {
+            error_report("%s: postcopy reply not fully consumed "
+                         "%d vs %zd",
+                         __func__, msg_i, fd_num);
+            return -1;
+        }
+
+        /*
+         * Now we've registered this with the postcopy code, we ack to the
+         * client, because now we're in the position to be able to deal
+         * with any faults it generates.
+         */
+        /* TODO: Use this for failure cases as well with a bad value. */
+        msg.hdr.size = sizeof(msg.payload.u64);
+        msg.payload.u64 = 0; /* OK */
+        if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
+            return -1;
         }
-    }
-    if (msg_i != fd_num) {
-        error_report("%s: postcopy reply not fully consumed "
-                     "%d vs %zd",
-                     __func__, msg_i, fd_num);
-        return -1;
-    }
-    /* Now we've registered this with the postcopy code, we ack to the client,
-     * because now we're in the position to be able to deal with any faults
-     * it generates.
-     */
-    /* TODO: Use this for failure cases as well with a bad value */
-    msg.hdr.size = sizeof(msg.payload.u64);
-    msg.payload.u64 = 0; /* OK */
-    if (vhost_user_write(dev, &msg, NULL, 0) < 0) {
-        return -1;
     }
 
     return 0;
@@ -568,17 +960,22 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev,
                                     struct vhost_memory *mem)
 {
     struct vhost_user *u = dev->opaque;
-    int fds[VHOST_MEMORY_MAX_NREGIONS];
+    int fds[VHOST_MEMORY_BASELINE_NREGIONS];
     size_t fd_num = 0;
     bool do_postcopy = u->postcopy_listen && u->postcopy_fd.handler;
     bool reply_supported = virtio_has_feature(dev->protocol_features,
                                               VHOST_USER_PROTOCOL_F_REPLY_ACK);
+    bool config_mem_slots =
+        virtio_has_feature(dev->protocol_features,
+                           VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS);
 
     if (do_postcopy) {
-        /* Postcopy has enough differences that it's best done in it's own
+        /*
+         * Postcopy has enough differences that it's best done in it's own
          * version
          */
-        return vhost_user_set_mem_table_postcopy(dev, mem);
+        return vhost_user_set_mem_table_postcopy(dev, mem, reply_supported,
+                                                 config_mem_slots);
     }
 
     VhostUserMsg msg = {
@@ -589,17 +986,23 @@ static int vhost_user_set_mem_table(struct vhost_dev *dev,
         msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK;
     }
 
-    if (vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
+    if (config_mem_slots) {
+        if (vhost_user_add_remove_regions(dev, &msg, reply_supported,
                                           false) < 0) {
-        return -1;
-    }
-
-    if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
-        return -1;
-    }
+            return -1;
+        }
+    } else {
+        if (vhost_user_fill_set_mem_table_msg(u, dev, &msg, fds, &fd_num,
+                                              false) < 0) {
+            return -1;
+        }
+        if (vhost_user_write(dev, &msg, fds, fd_num) < 0) {
+            return -1;
+        }
 
-    if (reply_supported) {
-        return process_message_reply(dev, &msg);
+        if (reply_supported) {
+            return process_message_reply(dev, &msg);
+        }
     }
 
     return 0;
@@ -764,7 +1167,7 @@ static int vhost_set_vring_file(struct vhost_dev *dev,
                                 VhostUserRequest request,
                                 struct vhost_vring_file *file)
 {
-    int fds[VHOST_MEMORY_MAX_NREGIONS];
+    int fds[VHOST_USER_MAX_RAM_SLOTS];
     size_t fd_num = 0;
     VhostUserMsg msg = {
         .hdr.request = request,
@@ -880,6 +1283,23 @@ static int vhost_user_set_owner(struct vhost_dev *dev)
     return 0;
 }
 
+static int vhost_user_get_max_memslots(struct vhost_dev *dev,
+                                       uint64_t *max_memslots)
+{
+    uint64_t backend_max_memslots;
+    int err;
+
+    err = vhost_user_get_u64(dev, VHOST_USER_GET_MAX_MEM_SLOTS,
+                             &backend_max_memslots);
+    if (err < 0) {
+        return err;
+    }
+
+    *max_memslots = backend_max_memslots;
+
+    return 0;
+}
+
 static int vhost_user_reset_device(struct vhost_dev *dev)
 {
     VhostUserMsg msg = {
@@ -1377,7 +1797,7 @@ static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
 
 static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
 {
-    uint64_t features, protocol_features;
+    uint64_t features, protocol_features, ram_slots;
     struct vhost_user *u;
     int err;
 
@@ -1439,6 +1859,27 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
                          "slave-req protocol features.");
             return -1;
         }
+
+        /* get max memory regions if backend supports configurable RAM slots */
+        if (!virtio_has_feature(dev->protocol_features,
+                                VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS)) {
+            u->user->memory_slots = VHOST_MEMORY_BASELINE_NREGIONS;
+        } else {
+            err = vhost_user_get_max_memslots(dev, &ram_slots);
+            if (err < 0) {
+                return err;
+            }
+
+            if (ram_slots < u->user->memory_slots) {
+                error_report("The backend specified a max ram slots limit "
+                             "of %" PRIu64", when the prior validated limit was %d. "
+                             "This limit should never decrease.", ram_slots,
+                             u->user->memory_slots);
+                return -1;
+            }
+
+            u->user->memory_slots = MIN(ram_slots, VHOST_USER_MAX_RAM_SLOTS);
+        }
     }
 
     if (dev->migration_blocker == NULL &&
@@ -1504,7 +1945,9 @@ static int vhost_user_get_vq_index(struct vhost_dev *dev, int idx)
 
 static int vhost_user_memslots_limit(struct vhost_dev *dev)
 {
-    return VHOST_MEMORY_MAX_NREGIONS;
+    struct vhost_user *u = dev->opaque;
+
+    return u->user->memory_slots;
 }
 
 static bool vhost_user_requires_shm_log(struct vhost_dev *dev)
@@ -1545,13 +1988,9 @@ static bool vhost_user_can_merge(struct vhost_dev *dev,
 {
     ram_addr_t offset;
     int mfd, rfd;
-    MemoryRegion *mr;
-
-    mr = memory_region_from_host((void *)(uintptr_t)start1, &offset);
-    mfd = memory_region_get_fd(mr);
 
-    mr = memory_region_from_host((void *)(uintptr_t)start2, &offset);
-    rfd = memory_region_get_fd(mr);
+    (void)vhost_user_get_mr_data(start1, &offset, &mfd);
+    (void)vhost_user_get_mr_data(start2, &offset, &rfd);
 
     return mfd == rfd;
 }
@@ -1893,6 +2332,7 @@ bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp)
         return false;
     }
     user->chr = chr;
+    user->memory_slots = 0;
     return true;
 }
 
diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c
new file mode 100644
index 0000000000..5b2ebf3496
--- /dev/null
+++ b/hw/virtio/vhost-vsock-common.c
@@ -0,0 +1,258 @@
+/*
+ * Parent class for vhost-vsock devices
+ *
+ * Copyright 2015-2020 Red Hat, Inc.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * (at your option) any later version.  See the COPYING file in the
+ * top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "standard-headers/linux/virtio_vsock.h"
+#include "qapi/error.h"
+#include "hw/virtio/virtio-access.h"
+#include "qemu/error-report.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/vhost-vsock.h"
+#include "qemu/iov.h"
+#include "monitor/monitor.h"
+
+int vhost_vsock_common_start(VirtIODevice *vdev)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    int ret;
+    int i;
+
+    if (!k->set_guest_notifiers) {
+        error_report("binding does not support guest notifiers");
+        return -ENOSYS;
+    }
+
+    ret = vhost_dev_enable_notifiers(&vvc->vhost_dev, vdev);
+    if (ret < 0) {
+        error_report("Error enabling host notifiers: %d", -ret);
+        return ret;
+    }
+
+    ret = k->set_guest_notifiers(qbus->parent, vvc->vhost_dev.nvqs, true);
+    if (ret < 0) {
+        error_report("Error binding guest notifier: %d", -ret);
+        goto err_host_notifiers;
+    }
+
+    vvc->vhost_dev.acked_features = vdev->guest_features;
+    ret = vhost_dev_start(&vvc->vhost_dev, vdev);
+    if (ret < 0) {
+        error_report("Error starting vhost: %d", -ret);
+        goto err_guest_notifiers;
+    }
+
+    /*
+     * guest_notifier_mask/pending not used yet, so just unmask
+     * everything here.  virtio-pci will do the right thing by
+     * enabling/disabling irqfd.
+     */
+    for (i = 0; i < vvc->vhost_dev.nvqs; i++) {
+        vhost_virtqueue_mask(&vvc->vhost_dev, vdev, i, false);
+    }
+
+    return 0;
+
+err_guest_notifiers:
+    k->set_guest_notifiers(qbus->parent, vvc->vhost_dev.nvqs, false);
+err_host_notifiers:
+    vhost_dev_disable_notifiers(&vvc->vhost_dev, vdev);
+    return ret;
+}
+
+void vhost_vsock_common_stop(VirtIODevice *vdev)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    int ret;
+
+    if (!k->set_guest_notifiers) {
+        return;
+    }
+
+    vhost_dev_stop(&vvc->vhost_dev, vdev);
+
+    ret = k->set_guest_notifiers(qbus->parent, vvc->vhost_dev.nvqs, false);
+    if (ret < 0) {
+        error_report("vhost guest notifier cleanup failed: %d", ret);
+        return;
+    }
+
+    vhost_dev_disable_notifiers(&vvc->vhost_dev, vdev);
+}
+
+
+static void vhost_vsock_common_handle_output(VirtIODevice *vdev, VirtQueue *vq)
+{
+    /* Do nothing */
+}
+
+static void vhost_vsock_common_guest_notifier_mask(VirtIODevice *vdev, int idx,
+                                            bool mask)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+
+    vhost_virtqueue_mask(&vvc->vhost_dev, vdev, idx, mask);
+}
+
+static bool vhost_vsock_common_guest_notifier_pending(VirtIODevice *vdev,
+                                               int idx)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+
+    return vhost_virtqueue_pending(&vvc->vhost_dev, idx);
+}
+
+static void vhost_vsock_common_send_transport_reset(VHostVSockCommon *vvc)
+{
+    VirtQueueElement *elem;
+    VirtQueue *vq = vvc->event_vq;
+    struct virtio_vsock_event event = {
+        .id = cpu_to_le32(VIRTIO_VSOCK_EVENT_TRANSPORT_RESET),
+    };
+
+    elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
+    if (!elem) {
+        error_report("vhost-vsock missed transport reset event");
+        return;
+    }
+
+    if (elem->out_num) {
+        error_report("invalid vhost-vsock event virtqueue element with "
+                     "out buffers");
+        goto out;
+    }
+
+    if (iov_from_buf(elem->in_sg, elem->in_num, 0,
+                     &event, sizeof(event)) != sizeof(event)) {
+        error_report("vhost-vsock event virtqueue element is too short");
+        goto out;
+    }
+
+    virtqueue_push(vq, elem, sizeof(event));
+    virtio_notify(VIRTIO_DEVICE(vvc), vq);
+
+out:
+    g_free(elem);
+}
+
+static void vhost_vsock_common_post_load_timer_cleanup(VHostVSockCommon *vvc)
+{
+    if (!vvc->post_load_timer) {
+        return;
+    }
+
+    timer_del(vvc->post_load_timer);
+    timer_free(vvc->post_load_timer);
+    vvc->post_load_timer = NULL;
+}
+
+static void vhost_vsock_common_post_load_timer_cb(void *opaque)
+{
+    VHostVSockCommon *vvc = opaque;
+
+    vhost_vsock_common_post_load_timer_cleanup(vvc);
+    vhost_vsock_common_send_transport_reset(vvc);
+}
+
+int vhost_vsock_common_pre_save(void *opaque)
+{
+    VHostVSockCommon *vvc = opaque;
+
+    /*
+     * At this point, backend must be stopped, otherwise
+     * it might keep writing to memory.
+     */
+    assert(!vvc->vhost_dev.started);
+
+    return 0;
+}
+
+int vhost_vsock_common_post_load(void *opaque, int version_id)
+{
+    VHostVSockCommon *vvc = opaque;
+    VirtIODevice *vdev = VIRTIO_DEVICE(vvc);
+
+    if (virtio_queue_get_addr(vdev, 2)) {
+        /*
+         * Defer transport reset event to a vm clock timer so that virtqueue
+         * changes happen after migration has completed.
+         */
+        assert(!vvc->post_load_timer);
+        vvc->post_load_timer =
+            timer_new_ns(QEMU_CLOCK_VIRTUAL,
+                         vhost_vsock_common_post_load_timer_cb,
+                         vvc);
+        timer_mod(vvc->post_load_timer, 1);
+    }
+    return 0;
+}
+
+void vhost_vsock_common_realize(VirtIODevice *vdev, const char *name)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+
+    virtio_init(vdev, name, VIRTIO_ID_VSOCK,
+                sizeof(struct virtio_vsock_config));
+
+    /* Receive and transmit queues belong to vhost */
+    vvc->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
+                                      vhost_vsock_common_handle_output);
+    vvc->trans_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
+                                       vhost_vsock_common_handle_output);
+
+    /* The event queue belongs to QEMU */
+    vvc->event_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
+                                       vhost_vsock_common_handle_output);
+
+    vvc->vhost_dev.nvqs = ARRAY_SIZE(vvc->vhost_vqs);
+    vvc->vhost_dev.vqs = vvc->vhost_vqs;
+
+    vvc->post_load_timer = NULL;
+}
+
+void vhost_vsock_common_unrealize(VirtIODevice *vdev)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+
+    vhost_vsock_common_post_load_timer_cleanup(vvc);
+
+    virtio_delete_queue(vvc->recv_vq);
+    virtio_delete_queue(vvc->trans_vq);
+    virtio_delete_queue(vvc->event_vq);
+    virtio_cleanup(vdev);
+}
+
+static void vhost_vsock_common_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
+    vdc->guest_notifier_mask = vhost_vsock_common_guest_notifier_mask;
+    vdc->guest_notifier_pending = vhost_vsock_common_guest_notifier_pending;
+}
+
+static const TypeInfo vhost_vsock_common_info = {
+    .name = TYPE_VHOST_VSOCK_COMMON,
+    .parent = TYPE_VIRTIO_DEVICE,
+    .instance_size = sizeof(VHostVSockCommon),
+    .class_init = vhost_vsock_common_class_init,
+    .abstract = true,
+};
+
+static void vhost_vsock_common_register_types(void)
+{
+    type_register_static(&vhost_vsock_common_info);
+}
+
+type_init(vhost_vsock_common_register_types)
diff --git a/hw/virtio/vhost-vsock.c b/hw/virtio/vhost-vsock.c
index 4a228f5168..c8f0699b4f 100644
--- a/hw/virtio/vhost-vsock.c
+++ b/hw/virtio/vhost-vsock.c
@@ -12,24 +12,14 @@
  */
 
 #include "qemu/osdep.h"
-#include <sys/ioctl.h>
 #include "standard-headers/linux/virtio_vsock.h"
 #include "qapi/error.h"
-#include "hw/virtio/virtio-bus.h"
 #include "hw/virtio/virtio-access.h"
 #include "qemu/error-report.h"
 #include "hw/qdev-properties.h"
 #include "hw/virtio/vhost-vsock.h"
-#include "qemu/iov.h"
-#include "qemu/module.h"
 #include "monitor/monitor.h"
 
-enum {
-    VHOST_VSOCK_SAVEVM_VERSION = 0,
-
-    VHOST_VSOCK_QUEUE_SIZE = 128,
-};
-
 static void vhost_vsock_get_config(VirtIODevice *vdev, uint8_t *config)
 {
     VHostVSock *vsock = VHOST_VSOCK(vdev);
@@ -39,16 +29,18 @@ static void vhost_vsock_get_config(VirtIODevice *vdev, uint8_t *config)
     memcpy(config, &vsockcfg, sizeof(vsockcfg));
 }
 
-static int vhost_vsock_set_guest_cid(VHostVSock *vsock)
+static int vhost_vsock_set_guest_cid(VirtIODevice *vdev)
 {
-    const VhostOps *vhost_ops = vsock->vhost_dev.vhost_ops;
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+    VHostVSock *vsock = VHOST_VSOCK(vdev);
+    const VhostOps *vhost_ops = vvc->vhost_dev.vhost_ops;
     int ret;
 
     if (!vhost_ops->vhost_vsock_set_guest_cid) {
         return -ENOSYS;
     }
 
-    ret = vhost_ops->vhost_vsock_set_guest_cid(&vsock->vhost_dev,
+    ret = vhost_ops->vhost_vsock_set_guest_cid(&vvc->vhost_dev,
                                                vsock->conf.guest_cid);
     if (ret < 0) {
         return -errno;
@@ -56,123 +48,58 @@ static int vhost_vsock_set_guest_cid(VHostVSock *vsock)
     return 0;
 }
 
-static int vhost_vsock_set_running(VHostVSock *vsock, int start)
+static int vhost_vsock_set_running(VirtIODevice *vdev, int start)
 {
-    const VhostOps *vhost_ops = vsock->vhost_dev.vhost_ops;
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+    const VhostOps *vhost_ops = vvc->vhost_dev.vhost_ops;
     int ret;
 
     if (!vhost_ops->vhost_vsock_set_running) {
         return -ENOSYS;
     }
 
-    ret = vhost_ops->vhost_vsock_set_running(&vsock->vhost_dev, start);
+    ret = vhost_ops->vhost_vsock_set_running(&vvc->vhost_dev, start);
     if (ret < 0) {
         return -errno;
     }
     return 0;
 }
 
-static void vhost_vsock_start(VirtIODevice *vdev)
-{
-    VHostVSock *vsock = VHOST_VSOCK(vdev);
-    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
-    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
-    int ret;
-    int i;
-
-    if (!k->set_guest_notifiers) {
-        error_report("binding does not support guest notifiers");
-        return;
-    }
-
-    ret = vhost_dev_enable_notifiers(&vsock->vhost_dev, vdev);
-    if (ret < 0) {
-        error_report("Error enabling host notifiers: %d", -ret);
-        return;
-    }
-
-    ret = k->set_guest_notifiers(qbus->parent, vsock->vhost_dev.nvqs, true);
-    if (ret < 0) {
-        error_report("Error binding guest notifier: %d", -ret);
-        goto err_host_notifiers;
-    }
-
-    vsock->vhost_dev.acked_features = vdev->guest_features;
-    ret = vhost_dev_start(&vsock->vhost_dev, vdev);
-    if (ret < 0) {
-        error_report("Error starting vhost: %d", -ret);
-        goto err_guest_notifiers;
-    }
-
-    ret = vhost_vsock_set_running(vsock, 1);
-    if (ret < 0) {
-        error_report("Error starting vhost vsock: %d", -ret);
-        goto err_dev_start;
-    }
-
-    /* guest_notifier_mask/pending not used yet, so just unmask
-     * everything here.  virtio-pci will do the right thing by
-     * enabling/disabling irqfd.
-     */
-    for (i = 0; i < vsock->vhost_dev.nvqs; i++) {
-        vhost_virtqueue_mask(&vsock->vhost_dev, vdev, i, false);
-    }
-
-    return;
-
-err_dev_start:
-    vhost_dev_stop(&vsock->vhost_dev, vdev);
-err_guest_notifiers:
-    k->set_guest_notifiers(qbus->parent, vsock->vhost_dev.nvqs, false);
-err_host_notifiers:
-    vhost_dev_disable_notifiers(&vsock->vhost_dev, vdev);
-}
-
-static void vhost_vsock_stop(VirtIODevice *vdev)
-{
-    VHostVSock *vsock = VHOST_VSOCK(vdev);
-    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
-    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
-    int ret;
-
-    if (!k->set_guest_notifiers) {
-        return;
-    }
-
-    ret = vhost_vsock_set_running(vsock, 0);
-    if (ret < 0) {
-        error_report("vhost vsock set running failed: %d", ret);
-        return;
-    }
-
-    vhost_dev_stop(&vsock->vhost_dev, vdev);
-
-    ret = k->set_guest_notifiers(qbus->parent, vsock->vhost_dev.nvqs, false);
-    if (ret < 0) {
-        error_report("vhost guest notifier cleanup failed: %d", ret);
-        return;
-    }
-
-    vhost_dev_disable_notifiers(&vsock->vhost_dev, vdev);
-}
 
 static void vhost_vsock_set_status(VirtIODevice *vdev, uint8_t status)
 {
-    VHostVSock *vsock = VHOST_VSOCK(vdev);
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
     bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
+    int ret;
 
     if (!vdev->vm_running) {
         should_start = false;
     }
 
-    if (vsock->vhost_dev.started == should_start) {
+    if (vvc->vhost_dev.started == should_start) {
         return;
     }
 
     if (should_start) {
-        vhost_vsock_start(vdev);
+        ret = vhost_vsock_common_start(vdev);
+        if (ret < 0) {
+            return;
+        }
+
+        ret = vhost_vsock_set_running(vdev, 1);
+        if (ret < 0) {
+            vhost_vsock_common_stop(vdev);
+            error_report("Error starting vhost vsock: %d", -ret);
+            return;
+        }
     } else {
-        vhost_vsock_stop(vdev);
+        ret = vhost_vsock_set_running(vdev, 0);
+        if (ret < 0) {
+            error_report("vhost vsock set running failed: %d", ret);
+            return;
+        }
+
+        vhost_vsock_common_stop(vdev);
     }
 }
 
@@ -184,108 +111,6 @@ static uint64_t vhost_vsock_get_features(VirtIODevice *vdev,
     return requested_features;
 }
 
-static void vhost_vsock_handle_output(VirtIODevice *vdev, VirtQueue *vq)
-{
-    /* Do nothing */
-}
-
-static void vhost_vsock_guest_notifier_mask(VirtIODevice *vdev, int idx,
-                                            bool mask)
-{
-    VHostVSock *vsock = VHOST_VSOCK(vdev);
-
-    vhost_virtqueue_mask(&vsock->vhost_dev, vdev, idx, mask);
-}
-
-static bool vhost_vsock_guest_notifier_pending(VirtIODevice *vdev, int idx)
-{
-    VHostVSock *vsock = VHOST_VSOCK(vdev);
-
-    return vhost_virtqueue_pending(&vsock->vhost_dev, idx);
-}
-
-static void vhost_vsock_send_transport_reset(VHostVSock *vsock)
-{
-    VirtQueueElement *elem;
-    VirtQueue *vq = vsock->event_vq;
-    struct virtio_vsock_event event = {
-        .id = cpu_to_le32(VIRTIO_VSOCK_EVENT_TRANSPORT_RESET),
-    };
-
-    elem = virtqueue_pop(vq, sizeof(VirtQueueElement));
-    if (!elem) {
-        error_report("vhost-vsock missed transport reset event");
-        return;
-    }
-
-    if (elem->out_num) {
-        error_report("invalid vhost-vsock event virtqueue element with "
-                     "out buffers");
-        goto out;
-    }
-
-    if (iov_from_buf(elem->in_sg, elem->in_num, 0,
-                     &event, sizeof(event)) != sizeof(event)) {
-        error_report("vhost-vsock event virtqueue element is too short");
-        goto out;
-    }
-
-    virtqueue_push(vq, elem, sizeof(event));
-    virtio_notify(VIRTIO_DEVICE(vsock), vq);
-
-out:
-    g_free(elem);
-}
-
-static void vhost_vsock_post_load_timer_cleanup(VHostVSock *vsock)
-{
-    if (!vsock->post_load_timer) {
-        return;
-    }
-
-    timer_del(vsock->post_load_timer);
-    timer_free(vsock->post_load_timer);
-    vsock->post_load_timer = NULL;
-}
-
-static void vhost_vsock_post_load_timer_cb(void *opaque)
-{
-    VHostVSock *vsock = opaque;
-
-    vhost_vsock_post_load_timer_cleanup(vsock);
-    vhost_vsock_send_transport_reset(vsock);
-}
-
-static int vhost_vsock_pre_save(void *opaque)
-{
-    VHostVSock *vsock = opaque;
-
-    /* At this point, backend must be stopped, otherwise
-     * it might keep writing to memory. */
-    assert(!vsock->vhost_dev.started);
-
-    return 0;
-}
-
-static int vhost_vsock_post_load(void *opaque, int version_id)
-{
-    VHostVSock *vsock = opaque;
-    VirtIODevice *vdev = VIRTIO_DEVICE(vsock);
-
-    if (virtio_queue_get_addr(vdev, 2)) {
-        /* Defer transport reset event to a vm clock timer so that virtqueue
-         * changes happen after migration has completed.
-         */
-        assert(!vsock->post_load_timer);
-        vsock->post_load_timer =
-            timer_new_ns(QEMU_CLOCK_VIRTUAL,
-                         vhost_vsock_post_load_timer_cb,
-                         vsock);
-        timer_mod(vsock->post_load_timer, 1);
-    }
-    return 0;
-}
-
 static const VMStateDescription vmstate_virtio_vhost_vsock = {
     .name = "virtio-vhost_vsock",
     .minimum_version_id = VHOST_VSOCK_SAVEVM_VERSION,
@@ -294,12 +119,13 @@ static const VMStateDescription vmstate_virtio_vhost_vsock = {
         VMSTATE_VIRTIO_DEVICE,
         VMSTATE_END_OF_LIST()
     },
-    .pre_save = vhost_vsock_pre_save,
-    .post_load = vhost_vsock_post_load,
+    .pre_save = vhost_vsock_common_pre_save,
+    .post_load = vhost_vsock_common_post_load,
 };
 
 static void vhost_vsock_device_realize(DeviceState *dev, Error **errp)
 {
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev);
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     VHostVSock *vsock = VHOST_VSOCK(dev);
     int vhostfd;
@@ -331,46 +157,29 @@ static void vhost_vsock_device_realize(DeviceState *dev, Error **errp)
         }
     }
 
-    virtio_init(vdev, "vhost-vsock", VIRTIO_ID_VSOCK,
-                sizeof(struct virtio_vsock_config));
-
-    /* Receive and transmit queues belong to vhost */
-    vsock->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
-                                      vhost_vsock_handle_output);
-    vsock->trans_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
-                                       vhost_vsock_handle_output);
+    vhost_vsock_common_realize(vdev, "vhost-vsock");
 
-    /* The event queue belongs to QEMU */
-    vsock->event_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE,
-                                       vhost_vsock_handle_output);
-
-    vsock->vhost_dev.nvqs = ARRAY_SIZE(vsock->vhost_vqs);
-    vsock->vhost_dev.vqs = vsock->vhost_vqs;
-    ret = vhost_dev_init(&vsock->vhost_dev, (void *)(uintptr_t)vhostfd,
+    ret = vhost_dev_init(&vvc->vhost_dev, (void *)(uintptr_t)vhostfd,
                          VHOST_BACKEND_TYPE_KERNEL, 0);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "vhost-vsock: vhost_dev_init failed");
         goto err_virtio;
     }
 
-    ret = vhost_vsock_set_guest_cid(vsock);
+    ret = vhost_vsock_set_guest_cid(vdev);
     if (ret < 0) {
         error_setg_errno(errp, -ret, "vhost-vsock: unable to set guest cid");
         goto err_vhost_dev;
     }
 
-    vsock->post_load_timer = NULL;
     return;
 
 err_vhost_dev:
-    vhost_dev_cleanup(&vsock->vhost_dev);
+    vhost_dev_cleanup(&vvc->vhost_dev);
     /* vhost_dev_cleanup() closes the vhostfd passed to vhost_dev_init() */
     vhostfd = -1;
 err_virtio:
-    virtio_delete_queue(vsock->recv_vq);
-    virtio_delete_queue(vsock->trans_vq);
-    virtio_delete_queue(vsock->event_vq);
-    virtio_cleanup(vdev);
+    vhost_vsock_common_unrealize(vdev);
     if (vhostfd >= 0) {
         close(vhostfd);
     }
@@ -379,19 +188,14 @@ err_virtio:
 
 static void vhost_vsock_device_unrealize(DeviceState *dev)
 {
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(dev);
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
-    VHostVSock *vsock = VHOST_VSOCK(dev);
-
-    vhost_vsock_post_load_timer_cleanup(vsock);
 
     /* This will stop vhost backend if appropriate. */
     vhost_vsock_set_status(vdev, 0);
 
-    vhost_dev_cleanup(&vsock->vhost_dev);
-    virtio_delete_queue(vsock->recv_vq);
-    virtio_delete_queue(vsock->trans_vq);
-    virtio_delete_queue(vsock->event_vq);
-    virtio_cleanup(vdev);
+    vhost_dev_cleanup(&vvc->vhost_dev);
+    vhost_vsock_common_unrealize(vdev);
 }
 
 static Property vhost_vsock_properties[] = {
@@ -407,19 +211,16 @@ static void vhost_vsock_class_init(ObjectClass *klass, void *data)
 
     device_class_set_props(dc, vhost_vsock_properties);
     dc->vmsd = &vmstate_virtio_vhost_vsock;
-    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
     vdc->realize = vhost_vsock_device_realize;
     vdc->unrealize = vhost_vsock_device_unrealize;
     vdc->get_features = vhost_vsock_get_features;
     vdc->get_config = vhost_vsock_get_config;
     vdc->set_status = vhost_vsock_set_status;
-    vdc->guest_notifier_mask = vhost_vsock_guest_notifier_mask;
-    vdc->guest_notifier_pending = vhost_vsock_guest_notifier_pending;
 }
 
 static const TypeInfo vhost_vsock_info = {
     .name = TYPE_VHOST_VSOCK,
-    .parent = TYPE_VIRTIO_DEVICE,
+    .parent = TYPE_VHOST_VSOCK_COMMON,
     .instance_size = sizeof(VHostVSock),
     .class_init = vhost_vsock_class_init,
 };
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index 065cd450f1..10507b2a43 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -321,6 +321,67 @@ static void balloon_stats_set_poll_interval(Object *obj, Visitor *v,
     balloon_stats_change_timer(s, 0);
 }
 
+static void virtio_balloon_handle_report(VirtIODevice *vdev, VirtQueue *vq)
+{
+    VirtIOBalloon *dev = VIRTIO_BALLOON(vdev);
+    VirtQueueElement *elem;
+
+    while ((elem = virtqueue_pop(vq, sizeof(VirtQueueElement)))) {
+        unsigned int i;
+
+        /*
+         * When we discard the page it has the effect of removing the page
+         * from the hypervisor itself and causing it to be zeroed when it
+         * is returned to us. So we must not discard the page if it is
+         * accessible by another device or process, or if the guest is
+         * expecting it to retain a non-zero value.
+         */
+        if (qemu_balloon_is_inhibited() || dev->poison_val) {
+            goto skip_element;
+        }
+
+        for (i = 0; i < elem->in_num; i++) {
+            void *addr = elem->in_sg[i].iov_base;
+            size_t size = elem->in_sg[i].iov_len;
+            ram_addr_t ram_offset;
+            RAMBlock *rb;
+
+            /*
+             * There is no need to check the memory section to see if
+             * it is ram/readonly/romd like there is for handle_output
+             * below. If the region is not meant to be written to then
+             * address_space_map will have allocated a bounce buffer
+             * and it will be freed in address_space_unmap and trigger
+             * and unassigned_mem_write before failing to copy over the
+             * buffer. If more than one bad descriptor is provided it
+             * will return NULL after the first bounce buffer and fail
+             * to map any resources.
+             */
+            rb = qemu_ram_block_from_host(addr, false, &ram_offset);
+            if (!rb) {
+                trace_virtio_balloon_bad_addr(elem->in_addr[i]);
+                continue;
+            }
+
+            /*
+             * For now we will simply ignore unaligned memory regions, or
+             * regions that overrun the end of the RAMBlock.
+             */
+            if (!QEMU_IS_ALIGNED(ram_offset | size, qemu_ram_pagesize(rb)) ||
+                (ram_offset + size) > qemu_ram_get_used_length(rb)) {
+                continue;
+            }
+
+            ram_block_discard_range(rb, ram_offset, size);
+        }
+
+skip_element:
+        virtqueue_push(vq, elem, 0);
+        virtio_notify(vdev, vq);
+        g_free(elem);
+    }
+}
+
 static void virtio_balloon_handle_output(VirtIODevice *vdev, VirtQueue *vq)
 {
     VirtIOBalloon *s = VIRTIO_BALLOON(vdev);
@@ -634,6 +695,7 @@ static void virtio_balloon_get_config(VirtIODevice *vdev, uint8_t *config_data)
 
     config.num_pages = cpu_to_le32(dev->num_pages);
     config.actual = cpu_to_le32(dev->actual);
+    config.poison_val = cpu_to_le32(dev->poison_val);
 
     if (dev->free_page_report_status == FREE_PAGE_REPORT_S_REQUESTED) {
         config.free_page_report_cmd_id =
@@ -683,6 +745,14 @@ static ram_addr_t get_current_ram_size(void)
     return size;
 }
 
+static bool virtio_balloon_page_poison_support(void *opaque)
+{
+    VirtIOBalloon *s = opaque;
+    VirtIODevice *vdev = VIRTIO_DEVICE(s);
+
+    return virtio_vdev_has_feature(vdev, VIRTIO_BALLOON_F_PAGE_POISON);
+}
+
 static void virtio_balloon_set_config(VirtIODevice *vdev,
                                       const uint8_t *config_data)
 {
@@ -697,6 +767,10 @@ static void virtio_balloon_set_config(VirtIODevice *vdev,
         qapi_event_send_balloon_change(vm_ram_size -
                         ((ram_addr_t) dev->actual << VIRTIO_BALLOON_PFN_SHIFT));
     }
+    dev->poison_val = 0;
+    if (virtio_balloon_page_poison_support(dev)) {
+        dev->poison_val = le32_to_cpu(config.poison_val);
+    }
     trace_virtio_balloon_set_config(dev->actual, oldactual);
 }
 
@@ -755,6 +829,17 @@ static const VMStateDescription vmstate_virtio_balloon_free_page_report = {
     }
 };
 
+static const VMStateDescription vmstate_virtio_balloon_page_poison = {
+    .name = "vitio-balloon-device/page-poison",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .needed = virtio_balloon_page_poison_support,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(poison_val, VirtIOBalloon),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 static const VMStateDescription vmstate_virtio_balloon_device = {
     .name = "virtio-balloon-device",
     .version_id = 1,
@@ -767,6 +852,7 @@ static const VMStateDescription vmstate_virtio_balloon_device = {
     },
     .subsections = (const VMStateDescription * []) {
         &vmstate_virtio_balloon_free_page_report,
+        &vmstate_virtio_balloon_page_poison,
         NULL
     }
 };
@@ -789,6 +875,13 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp)
         return;
     }
 
+    if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_FREE_PAGE_HINT) &&
+        !s->iothread) {
+        error_setg(errp, "'free-page-hint' requires 'iothread' to be set");
+        virtio_cleanup(vdev);
+        return;
+    }
+
     s->ivq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output);
     s->dvq = virtio_add_queue(vdev, 128, virtio_balloon_handle_output);
     s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats);
@@ -797,25 +890,18 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp)
                            VIRTIO_BALLOON_F_FREE_PAGE_HINT)) {
         s->free_page_vq = virtio_add_queue(vdev, VIRTQUEUE_MAX_SIZE,
                                            virtio_balloon_handle_free_page_vq);
-        s->free_page_report_status = FREE_PAGE_REPORT_S_STOP;
-        s->free_page_report_cmd_id =
-                           VIRTIO_BALLOON_FREE_PAGE_REPORT_CMD_ID_MIN;
-        s->free_page_report_notify.notify =
-                                       virtio_balloon_free_page_report_notify;
         precopy_add_notifier(&s->free_page_report_notify);
-        if (s->iothread) {
-            object_ref(OBJECT(s->iothread));
-            s->free_page_bh = aio_bh_new(iothread_get_aio_context(s->iothread),
-                                       virtio_ballloon_get_free_page_hints, s);
-            qemu_mutex_init(&s->free_page_lock);
-            qemu_cond_init(&s->free_page_cond);
-            s->block_iothread = false;
-        } else {
-            /* Simply disable this feature if the iothread wasn't created. */
-            s->host_features &= ~(1 << VIRTIO_BALLOON_F_FREE_PAGE_HINT);
-            virtio_error(vdev, "iothread is missing");
-        }
+
+        object_ref(OBJECT(s->iothread));
+        s->free_page_bh = aio_bh_new(iothread_get_aio_context(s->iothread),
+                                     virtio_ballloon_get_free_page_hints, s);
     }
+
+    if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_REPORTING)) {
+        s->reporting_vq = virtio_add_queue(vdev, 32,
+                                           virtio_balloon_handle_report);
+    }
+
     reset_stats(s);
 }
 
@@ -824,8 +910,9 @@ static void virtio_balloon_device_unrealize(DeviceState *dev)
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     VirtIOBalloon *s = VIRTIO_BALLOON(dev);
 
-    if (virtio_balloon_free_page_support(s)) {
+    if (s->free_page_bh) {
         qemu_bh_delete(s->free_page_bh);
+        object_unref(OBJECT(s->iothread));
         virtio_balloon_free_page_stop(s);
         precopy_remove_notifier(&s->free_page_report_notify);
     }
@@ -838,6 +925,9 @@ static void virtio_balloon_device_unrealize(DeviceState *dev)
     if (s->free_page_vq) {
         virtio_delete_queue(s->free_page_vq);
     }
+    if (s->reporting_vq) {
+        virtio_delete_queue(s->reporting_vq);
+    }
     virtio_cleanup(vdev);
 }
 
@@ -854,6 +944,8 @@ static void virtio_balloon_device_reset(VirtIODevice *vdev)
         g_free(s->stats_vq_elem);
         s->stats_vq_elem = NULL;
     }
+
+    s->poison_val = 0;
 }
 
 static void virtio_balloon_set_status(VirtIODevice *vdev, uint8_t status)
@@ -892,6 +984,11 @@ static void virtio_balloon_instance_init(Object *obj)
 {
     VirtIOBalloon *s = VIRTIO_BALLOON(obj);
 
+    qemu_mutex_init(&s->free_page_lock);
+    qemu_cond_init(&s->free_page_cond);
+    s->free_page_report_cmd_id = VIRTIO_BALLOON_FREE_PAGE_REPORT_CMD_ID_MIN;
+    s->free_page_report_notify.notify = virtio_balloon_free_page_report_notify;
+
     object_property_add(obj, "guest-stats", "guest statistics",
                         balloon_stats_get_all, NULL, NULL, s);
 
@@ -916,6 +1013,10 @@ static Property virtio_balloon_properties[] = {
                     VIRTIO_BALLOON_F_DEFLATE_ON_OOM, false),
     DEFINE_PROP_BIT("free-page-hint", VirtIOBalloon, host_features,
                     VIRTIO_BALLOON_F_FREE_PAGE_HINT, false),
+    DEFINE_PROP_BIT("page-poison", VirtIOBalloon, host_features,
+                    VIRTIO_BALLOON_F_PAGE_POISON, true),
+    DEFINE_PROP_BIT("free-page-reporting", VirtIOBalloon, host_features,
+                    VIRTIO_BALLOON_F_REPORTING, false),
     /* QEMU 4.0 accidentally changed the config size even when free-page-hint
      * is disabled, resulting in QEMU 3.1 migration incompatibility.  This
      * property retains this quirk for QEMU 4.1 machine types.
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index d028c17c24..7bc8c1c056 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -1273,16 +1273,20 @@ static void virtio_pci_common_write(void *opaque, hwaddr addr,
         virtio_queue_set_vector(vdev, vdev->queue_sel, val);
         break;
     case VIRTIO_PCI_COMMON_Q_ENABLE:
-        virtio_queue_set_num(vdev, vdev->queue_sel,
-                             proxy->vqs[vdev->queue_sel].num);
-        virtio_queue_set_rings(vdev, vdev->queue_sel,
+        if (val == 1) {
+            virtio_queue_set_num(vdev, vdev->queue_sel,
+                                 proxy->vqs[vdev->queue_sel].num);
+            virtio_queue_set_rings(vdev, vdev->queue_sel,
                        ((uint64_t)proxy->vqs[vdev->queue_sel].desc[1]) << 32 |
                        proxy->vqs[vdev->queue_sel].desc[0],
                        ((uint64_t)proxy->vqs[vdev->queue_sel].avail[1]) << 32 |
                        proxy->vqs[vdev->queue_sel].avail[0],
                        ((uint64_t)proxy->vqs[vdev->queue_sel].used[1]) << 32 |
                        proxy->vqs[vdev->queue_sel].used[0]);
-        proxy->vqs[vdev->queue_sel].enabled = 1;
+            proxy->vqs[vdev->queue_sel].enabled = 1;
+        } else {
+            virtio_error(vdev, "wrong value for queue_enable %"PRIx64, val);
+        }
         break;
     case VIRTIO_PCI_COMMON_Q_DESCLO:
         proxy->vqs[vdev->queue_sel].desc[0] = val;