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authorStefan Hajnoczi <stefanha@redhat.com>2023-10-05 09:01:01 -0400
committerStefan Hajnoczi <stefanha@redhat.com>2023-10-05 09:01:01 -0400
commit2f3913f4b2ad74baeb5a6f1d36efbd9ecdf1057d (patch)
tree2a77273973037c80a25b88dfa80bfc24baf7de52 /hw
parent800af0aae1cfa456701c5fa1ef273ce47585179c (diff)
parentce0f3b032a960726c0dddfb4f81f223215179f26 (diff)
downloadfocaccia-qemu-2f3913f4b2ad74baeb5a6f1d36efbd9ecdf1057d.tar.gz
focaccia-qemu-2f3913f4b2ad74baeb5a6f1d36efbd9ecdf1057d.zip
Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging
virtio,pci: features, cleanups

vdpa:
      shadow vq vlan support
      net migration with cvq
cxl:
     support emulating 4 HDM decoders
     serial number extended capability
virtio:
      hared dma-buf

Fixes, cleanups all over the place.

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

* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (53 commits)
  libvhost-user: handle shared_object msg
  vhost-user: add shared_object msg
  hw/display: introduce virtio-dmabuf
  util/uuid: add a hash function
  virtio: remove unused next argument from virtqueue_split_read_next_desc()
  virtio: remove unnecessary thread fence while reading next descriptor
  virtio: use shadow_avail_idx while checking number of heads
  libvhost-user.c: add assertion to vu_message_read_default
  pcie_sriov: unregister_vfs(): fix error path
  hw/i386/pc: improve physical address space bound check for 32-bit x86 systems
  amd_iommu: Fix APIC address check
  vdpa net: follow VirtIO initialization properly at cvq isolation probing
  vdpa net: stop probing if cannot set features
  vdpa net: fix error message setting virtio status
  hw/pci-bridge/cxl-upstream: Add serial number extended capability support
  hw/cxl: Support 4 HDM decoders at all levels of topology
  hw/cxl: Fix and use same calculation for HDM decoder block size everywhere
  hw/cxl: Add utility functions decoder interleave ways and target count.
  hw/cxl: Push cxl_decoder_count_enc() and cxl_decode_ig() into .c
  vdpa net: zero vhost_vdpa iova_tree pointer at cleanup
  ...

Conflicts:
  hw/core/machine.c
  Context conflict with commit 314e0a84cd5d ("hw/core: remove needless
  includes") because it removed an adjacent #include.
Diffstat (limited to 'hw')
-rw-r--r--hw/acpi/acpi-x86-stub.c6
-rw-r--r--hw/acpi/core.c9
-rw-r--r--hw/acpi/cpu.c9
-rw-r--r--hw/acpi/hmat.c1
-rw-r--r--hw/acpi/hmat.h3
-rw-r--r--hw/acpi/memory_hotplug.c1
-rw-r--r--hw/acpi/piix4.c5
-rw-r--r--hw/acpi/trace-events10
-rw-r--r--hw/core/machine.c5
-rw-r--r--hw/cxl/cxl-component-utils.c92
-rw-r--r--hw/cxl/cxl-host.c67
-rw-r--r--hw/display/meson.build1
-rw-r--r--hw/display/virtio-dmabuf.c138
-rw-r--r--hw/i386/acpi-build.c13
-rw-r--r--hw/i386/acpi-common.c5
-rw-r--r--hw/i386/acpi-common.h3
-rw-r--r--hw/i386/acpi-microvm.c3
-rw-r--r--hw/i386/amd_iommu.c9
-rw-r--r--hw/i386/amd_iommu.h2
-rw-r--r--hw/i386/generic_event_device_x86.c36
-rw-r--r--hw/i386/meson.build1
-rw-r--r--hw/i386/microvm.c2
-rw-r--r--hw/i386/pc.c32
-rw-r--r--hw/i386/pc_piix.c4
-rw-r--r--hw/i386/pc_q35.c2
-rw-r--r--hw/isa/lpc_ich9.c16
-rw-r--r--hw/mem/cxl_type3.c102
-rw-r--r--hw/net/virtio-net.c6
-rw-r--r--hw/pci-bridge/cxl_upstream.c15
-rw-r--r--hw/pci/pci.c2
-rw-r--r--hw/pci/pci_bridge.c14
-rw-r--r--hw/pci/pcie_sriov.c9
-rw-r--r--hw/scsi/vhost-user-scsi.c4
-rw-r--r--hw/virtio/meson.build28
-rw-r--r--hw/virtio/trace-events2
-rw-r--r--hw/virtio/vdpa-dev.c3
-rw-r--r--hw/virtio/vhost-shadow-virtqueue.c36
-rw-r--r--hw/virtio/vhost-shadow-virtqueue.h2
-rw-r--r--hw/virtio/vhost-user-device-pci.c71
-rw-r--r--hw/virtio/vhost-user-device.c380
-rw-r--r--hw/virtio/vhost-user-gpio.c7
-rw-r--r--hw/virtio/vhost-user.c188
-rw-r--r--hw/virtio/vhost-vdpa.c66
-rw-r--r--hw/virtio/virtio-qmp.c139
-rw-r--r--hw/virtio/virtio-qmp.h7
-rw-r--r--hw/virtio/virtio.c64
46 files changed, 1250 insertions, 370 deletions
diff --git a/hw/acpi/acpi-x86-stub.c b/hw/acpi/acpi-x86-stub.c
index d0d399d26b..9662a594ad 100644
--- a/hw/acpi/acpi-x86-stub.c
+++ b/hw/acpi/acpi-x86-stub.c
@@ -1,12 +1,6 @@
 #include "qemu/osdep.h"
-#include "hw/i386/pc.h"
 #include "hw/i386/acpi-build.h"
 
-void pc_madt_cpu_entry(int uid, const CPUArchIdList *apic_ids,
-                       GArray *entry, bool force_enabled)
-{
-}
-
 Object *acpi_get_i386_pci_host(void)
 {
        return NULL;
diff --git a/hw/acpi/core.c b/hw/acpi/core.c
index 00b1e79a30..ec5e127d17 100644
--- a/hw/acpi/core.c
+++ b/hw/acpi/core.c
@@ -32,6 +32,7 @@
 #include "qemu/module.h"
 #include "qemu/option.h"
 #include "sysemu/runstate.h"
+#include "trace.h"
 
 struct acpi_table_header {
     uint16_t _length;         /* our length, not actual part of the hdr */
@@ -688,9 +689,11 @@ void acpi_gpe_ioport_writeb(ACPIREGS *ar, uint32_t addr, uint32_t val)
 
     cur = acpi_gpe_ioport_get_ptr(ar, addr);
     if (addr < ar->gpe.len / 2) {
+        trace_acpi_gpe_sts_ioport_writeb(addr, val);
         /* GPE_STS */
         *cur = (*cur) & ~val;
     } else if (addr < ar->gpe.len) {
+        trace_acpi_gpe_en_ioport_writeb(addr - (ar->gpe.len / 2), val);
         /* GPE_EN */
         *cur = val;
     } else {
@@ -709,6 +712,12 @@ uint32_t acpi_gpe_ioport_readb(ACPIREGS *ar, uint32_t addr)
         val = *cur;
     }
 
+    if (addr < ar->gpe.len / 2) {
+        trace_acpi_gpe_sts_ioport_readb(addr, val);
+    } else {
+        trace_acpi_gpe_en_ioport_readb(addr - (ar->gpe.len / 2), val);
+    }
+
     return val;
 }
 
diff --git a/hw/acpi/cpu.c b/hw/acpi/cpu.c
index 19c154d78f..011d2c6c2d 100644
--- a/hw/acpi/cpu.c
+++ b/hw/acpi/cpu.c
@@ -1,6 +1,7 @@
 #include "qemu/osdep.h"
 #include "migration/vmstate.h"
 #include "hw/acpi/cpu.h"
+#include "hw/core/cpu.h"
 #include "qapi/error.h"
 #include "qapi/qapi-events-acpi.h"
 #include "trace.h"
@@ -338,7 +339,7 @@ const VMStateDescription vmstate_cpu_hotplug = {
 #define CPU_FW_EJECT_EVENT "CEJF"
 
 void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
-                    hwaddr io_base,
+                    build_madt_cpu_fn build_madt_cpu, hwaddr io_base,
                     const char *res_root,
                     const char *event_handler_method)
 {
@@ -353,8 +354,6 @@ void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
     MachineClass *mc = MACHINE_GET_CLASS(machine);
     const CPUArchIdList *arch_ids = mc->possible_cpu_arch_ids(machine);
     char *cphp_res_path = g_strdup_printf("%s." CPUHP_RES_DEVICE, res_root);
-    Object *obj = object_resolve_path_type("", TYPE_ACPI_DEVICE_IF, NULL);
-    AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(obj);
 
     cpu_ctrl_dev = aml_device("%s", cphp_res_path);
     {
@@ -664,9 +663,7 @@ void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
             aml_append(dev, method);
 
             /* build _MAT object */
-            assert(adevc && adevc->madt_cpu);
-            adevc->madt_cpu(i, arch_ids, madt_buf,
-                            true); /* set enabled flag */
+            build_madt_cpu(i, arch_ids, madt_buf, true); /* set enabled flag */
             aml_append(dev, aml_name_decl("_MAT",
                 aml_buffer(madt_buf->len, (uint8_t *)madt_buf->data)));
             g_array_free(madt_buf, true);
diff --git a/hw/acpi/hmat.c b/hw/acpi/hmat.c
index 2d5e199ba9..3042d223c8 100644
--- a/hw/acpi/hmat.c
+++ b/hw/acpi/hmat.c
@@ -27,6 +27,7 @@
 #include "qemu/osdep.h"
 #include "qemu/units.h"
 #include "sysemu/numa.h"
+#include "hw/acpi/aml-build.h"
 #include "hw/acpi/hmat.h"
 
 /*
diff --git a/hw/acpi/hmat.h b/hw/acpi/hmat.h
index b57f0e7e80..fd989cb661 100644
--- a/hw/acpi/hmat.h
+++ b/hw/acpi/hmat.h
@@ -27,7 +27,8 @@
 #ifndef HMAT_H
 #define HMAT_H
 
-#include "hw/acpi/aml-build.h"
+#include "hw/acpi/bios-linker-loader.h"
+#include "sysemu/numa.h"
 
 /*
  * ACPI 6.3: 5.2.27.3 Memory Proximity Domain Attributes Structure,
diff --git a/hw/acpi/memory_hotplug.c b/hw/acpi/memory_hotplug.c
index d926f4f77d..0b883df813 100644
--- a/hw/acpi/memory_hotplug.c
+++ b/hw/acpi/memory_hotplug.c
@@ -1,6 +1,7 @@
 #include "qemu/osdep.h"
 #include "hw/acpi/memory_hotplug.h"
 #include "hw/mem/pc-dimm.h"
+#include "hw/boards.h"
 #include "hw/qdev-core.h"
 #include "migration/vmstate.h"
 #include "trace.h"
diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c
index 63d2113b86..dd523d2e4c 100644
--- a/hw/acpi/piix4.c
+++ b/hw/acpi/piix4.c
@@ -20,7 +20,6 @@
  */
 
 #include "qemu/osdep.h"
-#include "hw/i386/pc.h"
 #include "hw/irq.h"
 #include "hw/isa/apm.h"
 #include "hw/i2c/pm_smbus.h"
@@ -43,7 +42,6 @@
 #include "hw/acpi/acpi_dev_interface.h"
 #include "migration/vmstate.h"
 #include "hw/core/cpu.h"
-#include "trace.h"
 #include "qom/object.h"
 
 #define GPE_BASE 0xafe0
@@ -518,7 +516,6 @@ static uint64_t gpe_readb(void *opaque, hwaddr addr, unsigned width)
     PIIX4PMState *s = opaque;
     uint32_t val = acpi_gpe_ioport_readb(&s->ar, addr);
 
-    trace_piix4_gpe_readb(addr, width, val);
     return val;
 }
 
@@ -527,7 +524,6 @@ static void gpe_writeb(void *opaque, hwaddr addr, uint64_t val,
 {
     PIIX4PMState *s = opaque;
 
-    trace_piix4_gpe_writeb(addr, width, val);
     acpi_gpe_ioport_writeb(&s->ar, addr, val);
     acpi_update_sci(&s->ar, s->irq);
 }
@@ -654,7 +650,6 @@ static void piix4_pm_class_init(ObjectClass *klass, void *data)
     hc->is_hotpluggable_bus = piix4_is_hotpluggable_bus;
     adevc->ospm_status = piix4_ospm_status;
     adevc->send_event = piix4_send_gpe;
-    adevc->madt_cpu = pc_madt_cpu_entry;
 }
 
 static const TypeInfo piix4_pm_info = {
diff --git a/hw/acpi/trace-events b/hw/acpi/trace-events
index 78e0a8670e..edc93e703c 100644
--- a/hw/acpi/trace-events
+++ b/hw/acpi/trace-events
@@ -17,6 +17,12 @@ mhp_acpi_clear_remove_evt(uint32_t slot) "slot[0x%"PRIx32"] clear remove event"
 mhp_acpi_pc_dimm_deleted(uint32_t slot) "slot[0x%"PRIx32"] pc-dimm deleted"
 mhp_acpi_pc_dimm_delete_failed(uint32_t slot) "slot[0x%"PRIx32"] pc-dimm delete failed"
 
+# core.c
+acpi_gpe_en_ioport_readb(uint32_t addr, uint8_t val) "addr: 0x%" PRIx32 " ==> 0x%02" PRIx8
+acpi_gpe_en_ioport_writeb(uint32_t addr, uint8_t val) "addr: 0x%" PRIx32 " <== 0x%02" PRIx8
+acpi_gpe_sts_ioport_readb(uint32_t addr, uint8_t val) "addr: 0x%" PRIx32 " ==> 0x%02" PRIx8
+acpi_gpe_sts_ioport_writeb(uint32_t addr, uint8_t val) "addr: 0x%" PRIx32 " <== 0x%02" PRIx8
+
 # cpu.c
 cpuhp_acpi_invalid_idx_selected(uint32_t idx) "0x%"PRIx32
 cpuhp_acpi_read_flags(uint32_t idx, uint8_t flags) "idx[0x%"PRIx32"] flags: 0x%"PRIx8
@@ -48,10 +54,6 @@ acpi_pci_sel_read(uint32_t val) "%" PRIu32
 acpi_pci_ej_write(uint64_t addr, uint64_t data) "0x%" PRIx64 " <== %" PRIu64
 acpi_pci_sel_write(uint64_t addr, uint64_t data) "0x%" PRIx64 " <== %" PRIu64
 
-# piix4.c
-piix4_gpe_readb(uint64_t addr, unsigned width, uint64_t val) "addr: 0x%" PRIx64 " width: %d ==> 0x%" PRIx64
-piix4_gpe_writeb(uint64_t addr, unsigned width, uint64_t val) "addr: 0x%" PRIx64 " width: %d <== 0x%" PRIx64
-
 # tco.c
 tco_timer_reload(int ticks, int msec) "ticks=%d (%d ms)"
 tco_timer_expired(int timeouts_no, bool strap, bool no_reboot) "timeouts_no=%d no_reboot=%d/%d"
diff --git a/hw/core/machine.c b/hw/core/machine.c
index 281ef0dccd..cfd1edfe20 100644
--- a/hw/core/machine.c
+++ b/hw/core/machine.c
@@ -24,6 +24,7 @@
 #include "sysemu/runstate.h"
 #include "sysemu/xen.h"
 #include "sysemu/qtest.h"
+#include "hw/pci/pci_bridge.h"
 #include "hw/mem/nvdimm.h"
 #include "migration/global_state.h"
 #include "exec/confidential-guest-support.h"
@@ -31,7 +32,9 @@
 #include "hw/virtio/virtio-net.h"
 #include "audio/audio.h"
 
-GlobalProperty hw_compat_8_1[] = {};
+GlobalProperty hw_compat_8_1[] = {
+    { TYPE_PCI_BRIDGE, "x-pci-express-writeable-slt-bug", "true" },
+};
 const size_t hw_compat_8_1_len = G_N_ELEMENTS(hw_compat_8_1);
 
 GlobalProperty hw_compat_8_0[] = {
diff --git a/hw/cxl/cxl-component-utils.c b/hw/cxl/cxl-component-utils.c
index 378f1082ce..f3bbf0fd13 100644
--- a/hw/cxl/cxl-component-utils.c
+++ b/hw/cxl/cxl-component-utils.c
@@ -13,6 +13,54 @@
 #include "hw/pci/pci.h"
 #include "hw/cxl/cxl.h"
 
+/* CXL r3.0 Section 8.2.4.19.1 CXL HDM Decoder Capability Register */
+int cxl_decoder_count_enc(int count)
+{
+    switch (count) {
+    case 1: return 0x0;
+    case 2: return 0x1;
+    case 4: return 0x2;
+    case 6: return 0x3;
+    case 8: return 0x4;
+    case 10: return 0x5;
+    /* Switches and Host Bridges may have more than 10 decoders */
+    case 12: return 0x6;
+    case 14: return 0x7;
+    case 16: return 0x8;
+    case 20: return 0x9;
+    case 24: return 0xa;
+    case 28: return 0xb;
+    case 32: return 0xc;
+    }
+    return 0;
+}
+
+int cxl_decoder_count_dec(int enc_cnt)
+{
+    switch (enc_cnt) {
+    case 0x0: return 1;
+    case 0x1: return 2;
+    case 0x2: return 4;
+    case 0x3: return 6;
+    case 0x4: return 8;
+    case 0x5: return 10;
+    /* Switches and Host Bridges may have more than 10 decoders */
+    case 0x6: return 12;
+    case 0x7: return 14;
+    case 0x8: return 16;
+    case 0x9: return 20;
+    case 0xa: return 24;
+    case 0xb: return 28;
+    case 0xc: return 32;
+    }
+    return 0;
+}
+
+hwaddr cxl_decode_ig(int ig)
+{
+    return 1ULL << (ig + 8);
+}
+
 static uint64_t cxl_cache_mem_read_reg(void *opaque, hwaddr offset,
                                        unsigned size)
 {
@@ -42,6 +90,9 @@ static void dumb_hdm_handler(CXLComponentState *cxl_cstate, hwaddr offset,
 
     switch (offset) {
     case A_CXL_HDM_DECODER0_CTRL:
+    case A_CXL_HDM_DECODER1_CTRL:
+    case A_CXL_HDM_DECODER2_CTRL:
+    case A_CXL_HDM_DECODER3_CTRL:
         should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT);
         should_uncommit = !should_commit;
         break;
@@ -81,7 +132,7 @@ static void cxl_cache_mem_write_reg(void *opaque, hwaddr offset, uint64_t value,
     }
 
     if (offset >= A_CXL_HDM_DECODER_CAPABILITY &&
-        offset <= A_CXL_HDM_DECODER0_TARGET_LIST_HI) {
+        offset <= A_CXL_HDM_DECODER3_TARGET_LIST_HI) {
         dumb_hdm_handler(cxl_cstate, offset, value);
     } else {
         cregs->cache_mem_registers[offset / sizeof(*cregs->cache_mem_registers)] = value;
@@ -161,7 +212,8 @@ static void ras_init_common(uint32_t *reg_state, uint32_t *write_msk)
 static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk,
                             enum reg_type type)
 {
-    int decoder_count = 1;
+    int decoder_count = CXL_HDM_DECODER_COUNT;
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     int i;
 
     ARRAY_FIELD_DP32(reg_state, CXL_HDM_DECODER_CAPABILITY, DECODER_COUNT,
@@ -174,19 +226,21 @@ static void hdm_init_common(uint32_t *reg_state, uint32_t *write_msk,
                      HDM_DECODER_ENABLE, 0);
     write_msk[R_CXL_HDM_DECODER_GLOBAL_CONTROL] = 0x3;
     for (i = 0; i < decoder_count; i++) {
-        write_msk[R_CXL_HDM_DECODER0_BASE_LO + i * 0x20] = 0xf0000000;
-        write_msk[R_CXL_HDM_DECODER0_BASE_HI + i * 0x20] = 0xffffffff;
-        write_msk[R_CXL_HDM_DECODER0_SIZE_LO + i * 0x20] = 0xf0000000;
-        write_msk[R_CXL_HDM_DECODER0_SIZE_HI + i * 0x20] = 0xffffffff;
-        write_msk[R_CXL_HDM_DECODER0_CTRL + i * 0x20] = 0x13ff;
+        write_msk[R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc] = 0xf0000000;
+        write_msk[R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc] = 0xffffffff;
+        write_msk[R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc] = 0xf0000000;
+        write_msk[R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc] = 0xffffffff;
+        write_msk[R_CXL_HDM_DECODER0_CTRL + i * hdm_inc] = 0x13ff;
         if (type == CXL2_DEVICE ||
             type == CXL2_TYPE3_DEVICE ||
             type == CXL2_LOGICAL_DEVICE) {
-            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * 0x20] = 0xf0000000;
+            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * hdm_inc] =
+                0xf0000000;
         } else {
-            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * 0x20] = 0xffffffff;
+            write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_LO + i * hdm_inc] =
+                0xffffffff;
         }
-        write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_HI + i * 0x20] = 0xffffffff;
+        write_msk[R_CXL_HDM_DECODER0_TARGET_LIST_HI + i * hdm_inc] = 0xffffffff;
     }
 }
 
@@ -375,6 +429,7 @@ void cxl_component_create_dvsec(CXLComponentState *cxl,
     cxl->dvsec_offset += length;
 }
 
+/* CXL r3.0 Section 8.2.4.19.7 CXL HDM Decoder n Control Register */
 uint8_t cxl_interleave_ways_enc(int iw, Error **errp)
 {
     switch (iw) {
@@ -392,6 +447,23 @@ uint8_t cxl_interleave_ways_enc(int iw, Error **errp)
     }
 }
 
+int cxl_interleave_ways_dec(uint8_t iw_enc, Error **errp)
+{
+    switch (iw_enc) {
+    case 0x0: return 1;
+    case 0x1: return 2;
+    case 0x2: return 4;
+    case 0x3: return 8;
+    case 0x4: return 16;
+    case 0x8: return 3;
+    case 0x9: return 6;
+    case 0xa: return 12;
+    default:
+        error_setg(errp, "Encoded interleave ways: %d not supported", iw_enc);
+        return 0;
+    }
+}
+
 uint8_t cxl_interleave_granularity_enc(uint64_t gran, Error **errp)
 {
     switch (gran) {
diff --git a/hw/cxl/cxl-host.c b/hw/cxl/cxl-host.c
index f0920da956..2aa776c79c 100644
--- a/hw/cxl/cxl-host.c
+++ b/hw/cxl/cxl-host.c
@@ -97,33 +97,58 @@ void cxl_fmws_link_targets(CXLState *cxl_state, Error **errp)
     }
 }
 
-/* TODO: support, multiple hdm decoders */
 static bool cxl_hdm_find_target(uint32_t *cache_mem, hwaddr addr,
                                 uint8_t *target)
 {
-    uint32_t ctrl;
-    uint32_t ig_enc;
-    uint32_t iw_enc;
-    uint32_t target_idx;
-
-    ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL];
-    if (!FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED)) {
-        return false;
-    }
-
-    ig_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IG);
-    iw_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IW);
-    target_idx = (addr / cxl_decode_ig(ig_enc)) % (1 << iw_enc);
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
+    unsigned int hdm_count;
+    bool found = false;
+    int i;
+    uint32_t cap;
+
+    cap = ldl_le_p(cache_mem + R_CXL_HDM_DECODER_CAPABILITY);
+    hdm_count = cxl_decoder_count_dec(FIELD_EX32(cap,
+                                                 CXL_HDM_DECODER_CAPABILITY,
+                                                 DECODER_COUNT));
+    for (i = 0; i < hdm_count; i++) {
+        uint32_t ctrl, ig_enc, iw_enc, target_idx;
+        uint32_t low, high;
+        uint64_t base, size;
+
+        low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc);
+        high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc);
+        base = (low & 0xf0000000) | ((uint64_t)high << 32);
+        low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc);
+        high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc);
+        size = (low & 0xf0000000) | ((uint64_t)high << 32);
+        if (addr < base || addr >= base + size) {
+            continue;
+        }
 
-    if (target_idx < 4) {
-        *target = extract32(cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_LO],
-                            target_idx * 8, 8);
-    } else {
-        *target = extract32(cache_mem[R_CXL_HDM_DECODER0_TARGET_LIST_HI],
-                            (target_idx - 4) * 8, 8);
+        ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + i * hdm_inc);
+        if (!FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED)) {
+            return false;
+        }
+        found = true;
+        ig_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IG);
+        iw_enc = FIELD_EX32(ctrl, CXL_HDM_DECODER0_CTRL, IW);
+        target_idx = (addr / cxl_decode_ig(ig_enc)) % (1 << iw_enc);
+
+        if (target_idx < 4) {
+            uint32_t val = ldl_le_p(cache_mem +
+                                    R_CXL_HDM_DECODER0_TARGET_LIST_LO +
+                                    i * hdm_inc);
+            *target = extract32(val, target_idx * 8, 8);
+        } else {
+            uint32_t val = ldl_le_p(cache_mem +
+                                    R_CXL_HDM_DECODER0_TARGET_LIST_HI +
+                                    i * hdm_inc);
+            *target = extract32(val, (target_idx - 4) * 8, 8);
+        }
+        break;
     }
 
-    return true;
+    return found;
 }
 
 static PCIDevice *cxl_cfmws_find_device(CXLFixedWindow *fw, hwaddr addr)
diff --git a/hw/display/meson.build b/hw/display/meson.build
index 413ba4ab24..05619c6968 100644
--- a/hw/display/meson.build
+++ b/hw/display/meson.build
@@ -37,6 +37,7 @@ system_ss.add(when: 'CONFIG_MACFB', if_true: files('macfb.c'))
 system_ss.add(when: 'CONFIG_NEXTCUBE', if_true: files('next-fb.c'))
 
 system_ss.add(when: 'CONFIG_VGA', if_true: files('vga.c'))
+system_ss.add(when: 'CONFIG_VIRTIO', if_true: files('virtio-dmabuf.c'))
 
 if (config_all_devices.has_key('CONFIG_VGA_CIRRUS') or
     config_all_devices.has_key('CONFIG_VGA_PCI') or
diff --git a/hw/display/virtio-dmabuf.c b/hw/display/virtio-dmabuf.c
new file mode 100644
index 0000000000..4a8e430f3d
--- /dev/null
+++ b/hw/display/virtio-dmabuf.c
@@ -0,0 +1,138 @@
+/*
+ * Virtio Shared dma-buf
+ *
+ * Copyright Red Hat, Inc. 2023
+ *
+ * Authors:
+ *     Albert Esteve <aesteve@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/virtio/virtio-dmabuf.h"
+
+
+static GMutex lock;
+static GHashTable *resource_uuids;
+
+/*
+ * uuid_equal_func: wrapper for UUID is_equal function to
+ * satisfy g_hash_table_new expected parameters signatures.
+ */
+static int uuid_equal_func(const void *lhv, const void *rhv)
+{
+    return qemu_uuid_is_equal(lhv, rhv);
+}
+
+static bool virtio_add_resource(QemuUUID *uuid, VirtioSharedObject *value)
+{
+    bool result = false;
+
+    g_mutex_lock(&lock);
+    if (resource_uuids == NULL) {
+        resource_uuids = g_hash_table_new_full(qemu_uuid_hash,
+                                               uuid_equal_func,
+                                               NULL,
+                                               g_free);
+    }
+    if (g_hash_table_lookup(resource_uuids, uuid) == NULL) {
+        result = g_hash_table_insert(resource_uuids, uuid, value);
+    }
+    g_mutex_unlock(&lock);
+
+    return result;
+}
+
+bool virtio_add_dmabuf(QemuUUID *uuid, int udmabuf_fd)
+{
+    bool result;
+    VirtioSharedObject *vso;
+    if (udmabuf_fd < 0) {
+        return false;
+    }
+    vso = g_new(VirtioSharedObject, 1);
+    vso->type = TYPE_DMABUF;
+    vso->value = GINT_TO_POINTER(udmabuf_fd);
+    result = virtio_add_resource(uuid, vso);
+
+    return result;
+}
+
+bool virtio_add_vhost_device(QemuUUID *uuid, struct vhost_dev *dev)
+{
+    bool result;
+    VirtioSharedObject *vso;
+    if (dev == NULL) {
+        return false;
+    }
+    vso = g_new(VirtioSharedObject, 1);
+    vso->type = TYPE_VHOST_DEV;
+    vso->value = dev;
+    result = virtio_add_resource(uuid, vso);
+
+    return result;
+}
+
+bool virtio_remove_resource(const QemuUUID *uuid)
+{
+    bool result;
+    g_mutex_lock(&lock);
+    result = g_hash_table_remove(resource_uuids, uuid);
+    g_mutex_unlock(&lock);
+
+    return result;
+}
+
+static VirtioSharedObject *get_shared_object(const QemuUUID *uuid)
+{
+    gpointer lookup_res = NULL;
+
+    g_mutex_lock(&lock);
+    if (resource_uuids != NULL) {
+        lookup_res = g_hash_table_lookup(resource_uuids, uuid);
+    }
+    g_mutex_unlock(&lock);
+
+    return (VirtioSharedObject *) lookup_res;
+}
+
+int virtio_lookup_dmabuf(const QemuUUID *uuid)
+{
+    VirtioSharedObject *vso = get_shared_object(uuid);
+    if (vso == NULL) {
+        return -1;
+    }
+    assert(vso->type == TYPE_DMABUF);
+    return GPOINTER_TO_INT(vso->value);
+}
+
+struct vhost_dev *virtio_lookup_vhost_device(const QemuUUID *uuid)
+{
+    VirtioSharedObject *vso = get_shared_object(uuid);
+    if (vso == NULL) {
+        return NULL;
+    }
+    assert(vso->type == TYPE_VHOST_DEV);
+    return (struct vhost_dev *) vso->value;
+}
+
+SharedObjectType virtio_object_type(const QemuUUID *uuid)
+{
+    VirtioSharedObject *vso = get_shared_object(uuid);
+    if (vso == NULL) {
+        return TYPE_INVALID;
+    }
+    return vso->type;
+}
+
+void virtio_free_resources(void)
+{
+    g_mutex_lock(&lock);
+    g_hash_table_destroy(resource_uuids);
+    /* Reference count shall be 0 after the implicit unref on destroy */
+    resource_uuids = NULL;
+    g_mutex_unlock(&lock);
+}
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 95199c8900..3f2b27cf75 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -1495,14 +1495,14 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
             aml_append(crs,
                 aml_io(
                        AML_DECODE16,
-                       ACPI_PORT_SMI_CMD,
-                       ACPI_PORT_SMI_CMD,
+                       pm->fadt.smi_cmd,
+                       pm->fadt.smi_cmd,
                        1,
                        2)
             );
             aml_append(dev, aml_name_decl("_CRS", crs));
             aml_append(dev, aml_operation_region("SMIR", AML_SYSTEM_IO,
-                aml_int(ACPI_PORT_SMI_CMD), 2));
+                aml_int(pm->fadt.smi_cmd), 2));
             field = aml_field("SMIR", AML_BYTE_ACC, AML_NOLOCK,
                               AML_WRITE_AS_ZEROS);
             aml_append(field, aml_named_field("SMIC", 8));
@@ -1549,8 +1549,8 @@ build_dsdt(GArray *table_data, BIOSLinker *linker,
             .smi_path = pm->smi_on_cpuhp ? "\\_SB.PCI0.SMI0.SMIC" : NULL,
             .fw_unplugs_cpu = pm->smi_on_cpu_unplug,
         };
-        build_cpus_aml(dsdt, machine, opts, pm->cpu_hp_io_base,
-                       "\\_SB.PCI0", "\\_GPE._E02");
+        build_cpus_aml(dsdt, machine, opts, pc_madt_cpu_entry,
+                       pm->cpu_hp_io_base, "\\_SB.PCI0", "\\_GPE._E02");
     }
 
     if (pcms->memhp_io_base && nr_mem) {
@@ -2547,8 +2547,7 @@ void acpi_build(AcpiBuildTables *tables, MachineState *machine)
 
     acpi_add_table(table_offsets, tables_blob);
     acpi_build_madt(tables_blob, tables->linker, x86ms,
-                    ACPI_DEVICE_IF(x86ms->acpi_dev), x86ms->oem_id,
-                    x86ms->oem_table_id);
+                    x86ms->oem_id, x86ms->oem_table_id);
 
 #ifdef CONFIG_ACPI_ERST
     {
diff --git a/hw/i386/acpi-common.c b/hw/i386/acpi-common.c
index 8a0932fe84..43dc23f7e0 100644
--- a/hw/i386/acpi-common.c
+++ b/hw/i386/acpi-common.c
@@ -94,14 +94,13 @@ build_xrupt_override(GArray *entry, uint8_t src, uint32_t gsi, uint16_t flags)
  * 5.2.8 Multiple APIC Description Table
  */
 void acpi_build_madt(GArray *table_data, BIOSLinker *linker,
-                     X86MachineState *x86ms, AcpiDeviceIf *adev,
+                     X86MachineState *x86ms,
                      const char *oem_id, const char *oem_table_id)
 {
     int i;
     bool x2apic_mode = false;
     MachineClass *mc = MACHINE_GET_CLASS(x86ms);
     const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(MACHINE(x86ms));
-    AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_GET_CLASS(adev);
     AcpiTable table = { .sig = "APIC", .rev = 3, .oem_id = oem_id,
                         .oem_table_id = oem_table_id };
 
@@ -111,7 +110,7 @@ void acpi_build_madt(GArray *table_data, BIOSLinker *linker,
     build_append_int_noprefix(table_data, 1 /* PCAT_COMPAT */, 4); /* Flags */
 
     for (i = 0; i < apic_ids->len; i++) {
-        adevc->madt_cpu(i, apic_ids, table_data, false);
+        pc_madt_cpu_entry(i, apic_ids, table_data, false);
         if (apic_ids->cpus[i].arch_id > 254) {
             x2apic_mode = true;
         }
diff --git a/hw/i386/acpi-common.h b/hw/i386/acpi-common.h
index a68825acf5..b3c56ee014 100644
--- a/hw/i386/acpi-common.h
+++ b/hw/i386/acpi-common.h
@@ -1,7 +1,6 @@
 #ifndef HW_I386_ACPI_COMMON_H
 #define HW_I386_ACPI_COMMON_H
 
-#include "hw/acpi/acpi_dev_interface.h"
 #include "hw/acpi/bios-linker-loader.h"
 #include "hw/i386/x86.h"
 
@@ -9,7 +8,7 @@
 #define ACPI_BUILD_IOAPIC_ID 0x0
 
 void acpi_build_madt(GArray *table_data, BIOSLinker *linker,
-                     X86MachineState *x86ms, AcpiDeviceIf *adev,
+                     X86MachineState *x86ms,
                      const char *oem_id, const char *oem_table_id);
 
 #endif
diff --git a/hw/i386/acpi-microvm.c b/hw/i386/acpi-microvm.c
index a075360d85..fec22d85c1 100644
--- a/hw/i386/acpi-microvm.c
+++ b/hw/i386/acpi-microvm.c
@@ -214,8 +214,7 @@ static void acpi_build_microvm(AcpiBuildTables *tables,
 
     acpi_add_table(table_offsets, tables_blob);
     acpi_build_madt(tables_blob, tables->linker, X86_MACHINE(machine),
-                    ACPI_DEVICE_IF(x86ms->acpi_dev), x86ms->oem_id,
-                    x86ms->oem_table_id);
+                    x86ms->oem_id, x86ms->oem_table_id);
 
 #ifdef CONFIG_ACPI_ERST
     {
diff --git a/hw/i386/amd_iommu.c b/hw/i386/amd_iommu.c
index c98a3c6e11..8d0f2f99dd 100644
--- a/hw/i386/amd_iommu.c
+++ b/hw/i386/amd_iommu.c
@@ -1246,13 +1246,8 @@ static int amdvi_int_remap_msi(AMDVIState *iommu,
         return -AMDVI_IR_ERR;
     }
 
-    if (origin->address & AMDVI_MSI_ADDR_HI_MASK) {
-        trace_amdvi_err("MSI address high 32 bits non-zero when "
-                        "Interrupt Remapping enabled.");
-        return -AMDVI_IR_ERR;
-    }
-
-    if ((origin->address & AMDVI_MSI_ADDR_LO_MASK) != APIC_DEFAULT_ADDRESS) {
+    if (origin->address < AMDVI_INT_ADDR_FIRST ||
+        origin->address + sizeof(origin->data) > AMDVI_INT_ADDR_LAST + 1) {
         trace_amdvi_err("MSI is not from IOAPIC.");
         return -AMDVI_IR_ERR;
     }
diff --git a/hw/i386/amd_iommu.h b/hw/i386/amd_iommu.h
index 6da893ee57..c5065a3e27 100644
--- a/hw/i386/amd_iommu.h
+++ b/hw/i386/amd_iommu.h
@@ -210,8 +210,6 @@
 #define AMDVI_INT_ADDR_FIRST    0xfee00000
 #define AMDVI_INT_ADDR_LAST     0xfeefffff
 #define AMDVI_INT_ADDR_SIZE     (AMDVI_INT_ADDR_LAST - AMDVI_INT_ADDR_FIRST + 1)
-#define AMDVI_MSI_ADDR_HI_MASK  (0xffffffff00000000ULL)
-#define AMDVI_MSI_ADDR_LO_MASK  (0x00000000ffffffffULL)
 
 /* SB IOAPIC is always on this device in AMD systems */
 #define AMDVI_IOAPIC_SB_DEVID   PCI_BUILD_BDF(0, PCI_DEVFN(0x14, 0))
diff --git a/hw/i386/generic_event_device_x86.c b/hw/i386/generic_event_device_x86.c
deleted file mode 100644
index e26fb02a2e..0000000000
--- a/hw/i386/generic_event_device_x86.c
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * x86 variant of the generic event device for hw reduced acpi
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms and conditions of the GNU General Public License,
- * version 2 or later, as published by the Free Software Foundation.
- */
-
-#include "qemu/osdep.h"
-#include "hw/acpi/generic_event_device.h"
-#include "hw/i386/pc.h"
-
-static void acpi_ged_x86_class_init(ObjectClass *class, void *data)
-{
-    AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_CLASS(class);
-
-    adevc->madt_cpu = pc_madt_cpu_entry;
-}
-
-static const TypeInfo acpi_ged_x86_info = {
-    .name          = TYPE_ACPI_GED_X86,
-    .parent        = TYPE_ACPI_GED,
-    .class_init    = acpi_ged_x86_class_init,
-    .interfaces = (InterfaceInfo[]) {
-        { TYPE_HOTPLUG_HANDLER },
-        { TYPE_ACPI_DEVICE_IF },
-        { }
-    }
-};
-
-static void acpi_ged_x86_register_types(void)
-{
-    type_register_static(&acpi_ged_x86_info);
-}
-
-type_init(acpi_ged_x86_register_types)
diff --git a/hw/i386/meson.build b/hw/i386/meson.build
index cfdbfdcbcb..ff879069c9 100644
--- a/hw/i386/meson.build
+++ b/hw/i386/meson.build
@@ -20,7 +20,6 @@ i386_ss.add(when: 'CONFIG_SGX', if_true: files('sgx-epc.c','sgx.c'),
                                 if_false: files('sgx-stub.c'))
 
 i386_ss.add(when: 'CONFIG_ACPI', if_true: files('acpi-common.c'))
-i386_ss.add(when: 'CONFIG_ACPI_HW_REDUCED', if_true: files('generic_event_device_x86.c'))
 i386_ss.add(when: 'CONFIG_PC', if_true: files(
   'pc.c',
   'pc_sysfw.c',
diff --git a/hw/i386/microvm.c b/hw/i386/microvm.c
index 8deeb62774..b9c93039e2 100644
--- a/hw/i386/microvm.c
+++ b/hw/i386/microvm.c
@@ -204,7 +204,7 @@ static void microvm_devices_init(MicrovmMachineState *mms)
 
     /* Optional and legacy devices */
     if (x86_machine_is_acpi_enabled(x86ms)) {
-        DeviceState *dev = qdev_new(TYPE_ACPI_GED_X86);
+        DeviceState *dev = qdev_new(TYPE_ACPI_GED);
         qdev_prop_set_uint32(dev, "ged-event", ACPI_GED_PWR_DOWN_EVT);
         sysbus_mmio_map(SYS_BUS_DEVICE(dev), 0, GED_MMIO_BASE);
         /* sysbus_mmio_map(SYS_BUS_DEVICE(dev), 1, GED_MMIO_BASE_MEMHP); */
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index ec01d74482..aad7e8ccd1 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -814,13 +814,39 @@ static uint64_t pc_get_cxl_range_end(PCMachineState *pcms)
 static hwaddr pc_max_used_gpa(PCMachineState *pcms, uint64_t pci_hole64_size)
 {
     X86CPU *cpu = X86_CPU(first_cpu);
+    PCMachineClass *pcmc = PC_MACHINE_GET_CLASS(pcms);
+    MachineState *ms = MACHINE(pcms);
 
-    /* 32-bit systems don't have hole64 thus return max CPU address */
-    if (cpu->phys_bits <= 32) {
+    if (cpu->env.features[FEAT_8000_0001_EDX] & CPUID_EXT2_LM) {
+        /* 64-bit systems */
+        return pc_pci_hole64_start() + pci_hole64_size - 1;
+    }
+
+    /* 32-bit systems */
+    if (pcmc->broken_32bit_mem_addr_check) {
+        /* old value for compatibility reasons */
         return ((hwaddr)1 << cpu->phys_bits) - 1;
     }
 
-    return pc_pci_hole64_start() + pci_hole64_size - 1;
+    /*
+     * 32-bit systems don't have hole64 but they might have a region for
+     * memory devices. Even if additional hotplugged memory devices might
+     * not be usable by most guest OSes, we need to still consider them for
+     * calculating the highest possible GPA so that we can properly report
+     * if someone configures them on a CPU that cannot possibly address them.
+     */
+    if (pcmc->has_reserved_memory &&
+        (ms->ram_size < ms->maxram_size)) {
+        hwaddr devmem_start;
+        ram_addr_t devmem_size;
+
+        pc_get_device_memory_range(pcms, &devmem_start, &devmem_size);
+        devmem_start += devmem_size;
+        return devmem_start - 1;
+    }
+
+    /* configuration without any memory hotplug */
+    return pc_above_4g_end(pcms) - 1;
 }
 
 /*
diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index ff8654ecda..e36a3262b2 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -496,9 +496,13 @@ DEFINE_I440FX_MACHINE(v8_2, "pc-i440fx-8.2", NULL,
 
 static void pc_i440fx_8_1_machine_options(MachineClass *m)
 {
+    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
+
     pc_i440fx_8_2_machine_options(m);
     m->alias = NULL;
     m->is_default = false;
+    pcmc->broken_32bit_mem_addr_check = true;
+
     compat_props_add(m->compat_props, hw_compat_8_1, hw_compat_8_1_len);
     compat_props_add(m->compat_props, pc_compat_8_1, pc_compat_8_1_len);
 }
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 2dd1158b70..a7386f2ca2 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -394,8 +394,10 @@ DEFINE_Q35_MACHINE(v8_2, "pc-q35-8.2", NULL,
 
 static void pc_q35_8_1_machine_options(MachineClass *m)
 {
+    PCMachineClass *pcmc = PC_MACHINE_CLASS(m);
     pc_q35_8_2_machine_options(m);
     m->alias = NULL;
+    pcmc->broken_32bit_mem_addr_check = true;
     compat_props_add(m->compat_props, hw_compat_8_1, hw_compat_8_1_len);
     compat_props_add(m->compat_props, pc_compat_8_1, pc_compat_8_1_len);
 }
diff --git a/hw/isa/lpc_ich9.c b/hw/isa/lpc_ich9.c
index 9c47a2f6c7..3f59980aa0 100644
--- a/hw/isa/lpc_ich9.c
+++ b/hw/isa/lpc_ich9.c
@@ -304,6 +304,21 @@ static PCIINTxRoute ich9_route_intx_pin_to_irq(void *opaque, int pirq_pin)
             route.irq = -1;
         }
     } else {
+        /*
+         * Strictly speaking, this is wrong. The PIRQ should be routed
+         * to *both* the I/O APIC and the PIC, on different pins. The
+         * I/O APIC has a fixed mapping to IRQ16-23, while the PIC is
+         * routed according to the PIRQx_ROUT configuration. But QEMU
+         * doesn't (yet) cope with the concept of pin numbers differing
+         * between PIC and I/O APIC, and neither does the in-kernel KVM
+         * irqchip support. So we route to the I/O APIC *only* if the
+         * routing to the PIC is disabled in the PIRQx_ROUT settings.
+         *
+         * This seems to work even if we boot a Linux guest with 'noapic'
+         * to make it use the legacy PIC, and then kexec directly into a
+         * new kernel which uses the I/O APIC. The new kernel explicitly
+         * disables the PIRQ routing even though it doesn't need to care.
+         */
         route.irq = ich9_pirq_to_gsi(pirq_pin);
     }
 
@@ -876,7 +891,6 @@ static void ich9_lpc_class_init(ObjectClass *klass, void *data)
     hc->is_hotpluggable_bus = ich9_pm_is_hotpluggable_bus;
     adevc->ospm_status = ich9_pm_ospm_status;
     adevc->send_event = ich9_send_gpe;
-    adevc->madt_cpu = pc_madt_cpu_entry;
     amldevc->build_dev_aml = build_ich9_isa_aml;
 }
 
diff --git a/hw/mem/cxl_type3.c b/hw/mem/cxl_type3.c
index 4cdcb3f7e7..c02be4ce45 100644
--- a/hw/mem/cxl_type3.c
+++ b/hw/mem/cxl_type3.c
@@ -388,34 +388,32 @@ static void build_dvsecs(CXLType3Dev *ct3d)
 
 static void hdm_decoder_commit(CXLType3Dev *ct3d, int which)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     ComponentRegisters *cregs = &ct3d->cxl_cstate.crb;
     uint32_t *cache_mem = cregs->cache_mem_registers;
     uint32_t ctrl;
 
-    assert(which == 0);
-
-    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL);
+    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc);
     /* TODO: Sanity checks that the decoder is possible */
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, ERR, 0);
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED, 1);
 
-    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL, ctrl);
+    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc, ctrl);
 }
 
 static void hdm_decoder_uncommit(CXLType3Dev *ct3d, int which)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     ComponentRegisters *cregs = &ct3d->cxl_cstate.crb;
     uint32_t *cache_mem = cregs->cache_mem_registers;
     uint32_t ctrl;
 
-    assert(which == 0);
-
-    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL);
+    ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc);
 
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, ERR, 0);
     ctrl = FIELD_DP32(ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED, 0);
 
-    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL, ctrl);
+    stl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + which * hdm_inc, ctrl);
 }
 
 static int ct3d_qmp_uncor_err_to_cxl(CxlUncorErrorType qmp_err)
@@ -498,6 +496,21 @@ static void ct3d_reg_write(void *opaque, hwaddr offset, uint64_t value,
         should_uncommit = !should_commit;
         which_hdm = 0;
         break;
+    case A_CXL_HDM_DECODER1_CTRL:
+        should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT);
+        should_uncommit = !should_commit;
+        which_hdm = 1;
+        break;
+    case A_CXL_HDM_DECODER2_CTRL:
+        should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT);
+        should_uncommit = !should_commit;
+        which_hdm = 2;
+        break;
+    case A_CXL_HDM_DECODER3_CTRL:
+        should_commit = FIELD_EX32(value, CXL_HDM_DECODER0_CTRL, COMMIT);
+        should_uncommit = !should_commit;
+        which_hdm = 3;
+        break;
     case A_CXL_RAS_UNC_ERR_STATUS:
     {
         uint32_t capctrl = ldl_le_p(cache_mem + R_CXL_RAS_ERR_CAP_CTRL);
@@ -769,36 +782,63 @@ static void ct3_exit(PCIDevice *pci_dev)
     }
 }
 
-/* TODO: Support multiple HDM decoders and DPA skip */
 static bool cxl_type3_dpa(CXLType3Dev *ct3d, hwaddr host_addr, uint64_t *dpa)
 {
+    int hdm_inc = R_CXL_HDM_DECODER1_BASE_LO - R_CXL_HDM_DECODER0_BASE_LO;
     uint32_t *cache_mem = ct3d->cxl_cstate.crb.cache_mem_registers;
-    uint64_t decoder_base, decoder_size, hpa_offset;
-    uint32_t hdm0_ctrl;
-    int ig, iw;
+    unsigned int hdm_count;
+    uint32_t cap;
+    uint64_t dpa_base = 0;
+    int i;
 
-    decoder_base = (((uint64_t)cache_mem[R_CXL_HDM_DECODER0_BASE_HI] << 32) |
-                    cache_mem[R_CXL_HDM_DECODER0_BASE_LO]);
-    if ((uint64_t)host_addr < decoder_base) {
-        return false;
-    }
+    cap = ldl_le_p(cache_mem + R_CXL_HDM_DECODER_CAPABILITY);
+    hdm_count = cxl_decoder_count_dec(FIELD_EX32(cap,
+                                                 CXL_HDM_DECODER_CAPABILITY,
+                                                 DECODER_COUNT));
+
+    for (i = 0; i < hdm_count; i++) {
+        uint64_t decoder_base, decoder_size, hpa_offset, skip;
+        uint32_t hdm_ctrl, low, high;
+        int ig, iw;
+
+        low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_BASE_LO + i * hdm_inc);
+        high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_BASE_HI + i * hdm_inc);
+        decoder_base = ((uint64_t)high << 32) | (low & 0xf0000000);
+
+        low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_SIZE_LO + i * hdm_inc);
+        high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_SIZE_HI + i * hdm_inc);
+        decoder_size = ((uint64_t)high << 32) | (low & 0xf0000000);
+
+        low = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_DPA_SKIP_LO +
+                       i * hdm_inc);
+        high = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_DPA_SKIP_HI +
+                        i * hdm_inc);
+        skip = ((uint64_t)high << 32) | (low & 0xf0000000);
+        dpa_base += skip;
+
+        hpa_offset = (uint64_t)host_addr - decoder_base;
+
+        hdm_ctrl = ldl_le_p(cache_mem + R_CXL_HDM_DECODER0_CTRL + i * hdm_inc);
+        iw = FIELD_EX32(hdm_ctrl, CXL_HDM_DECODER0_CTRL, IW);
+        ig = FIELD_EX32(hdm_ctrl, CXL_HDM_DECODER0_CTRL, IG);
+        if (!FIELD_EX32(hdm_ctrl, CXL_HDM_DECODER0_CTRL, COMMITTED)) {
+            return false;
+        }
+        if (((uint64_t)host_addr < decoder_base) ||
+            (hpa_offset >= decoder_size)) {
+            dpa_base += decoder_size /
+                cxl_interleave_ways_dec(iw, &error_fatal);
+            continue;
+        }
 
-    hpa_offset = (uint64_t)host_addr - decoder_base;
+        *dpa = dpa_base +
+            ((MAKE_64BIT_MASK(0, 8 + ig) & hpa_offset) |
+             ((MAKE_64BIT_MASK(8 + ig + iw, 64 - 8 - ig - iw) & hpa_offset)
+              >> iw));
 
-    decoder_size = ((uint64_t)cache_mem[R_CXL_HDM_DECODER0_SIZE_HI] << 32) |
-        cache_mem[R_CXL_HDM_DECODER0_SIZE_LO];
-    if (hpa_offset >= decoder_size) {
-        return false;
+        return true;
     }
-
-    hdm0_ctrl = cache_mem[R_CXL_HDM_DECODER0_CTRL];
-    iw = FIELD_EX32(hdm0_ctrl, CXL_HDM_DECODER0_CTRL, IW);
-    ig = FIELD_EX32(hdm0_ctrl, CXL_HDM_DECODER0_CTRL, IG);
-
-    *dpa = (MAKE_64BIT_MASK(0, 8 + ig) & hpa_offset) |
-        ((MAKE_64BIT_MASK(8 + ig + iw, 64 - 8 - ig - iw) & hpa_offset) >> iw);
-
-    return true;
+    return false;
 }
 
 static int cxl_type3_hpa_to_as_and_dpa(CXLType3Dev *ct3d,
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 5a0201c423..29e33ea5ed 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -49,8 +49,6 @@
 
 #define VIRTIO_NET_VM_VERSION    11
 
-#define MAX_VLAN    (1 << 12)   /* Per 802.1Q definition */
-
 /* previously fixed value */
 #define VIRTIO_NET_RX_QUEUE_DEFAULT_SIZE 256
 #define VIRTIO_NET_TX_QUEUE_DEFAULT_SIZE 256
@@ -1029,9 +1027,7 @@ static void virtio_net_set_features(VirtIODevice *vdev, uint64_t features)
         vhost_net_save_acked_features(nc->peer);
     }
 
-    if (virtio_has_feature(features, VIRTIO_NET_F_CTRL_VLAN)) {
-        memset(n->vlans, 0, MAX_VLAN >> 3);
-    } else {
+    if (!virtio_has_feature(features, VIRTIO_NET_F_CTRL_VLAN)) {
         memset(n->vlans, 0xff, MAX_VLAN >> 3);
     }
 
diff --git a/hw/pci-bridge/cxl_upstream.c b/hw/pci-bridge/cxl_upstream.c
index 2b9cf0cc97..a57806fb31 100644
--- a/hw/pci-bridge/cxl_upstream.c
+++ b/hw/pci-bridge/cxl_upstream.c
@@ -14,14 +14,21 @@
 #include "hw/pci/msi.h"
 #include "hw/pci/pcie.h"
 #include "hw/pci/pcie_port.h"
+/*
+ * Null value of all Fs suggested by IEEE RA guidelines for use of
+ * EU, OUI and CID
+ */
+#define UI64_NULL (~0ULL)
 
 #define CXL_UPSTREAM_PORT_MSI_NR_VECTOR 2
 
 #define CXL_UPSTREAM_PORT_MSI_OFFSET 0x70
 #define CXL_UPSTREAM_PORT_PCIE_CAP_OFFSET 0x90
 #define CXL_UPSTREAM_PORT_AER_OFFSET 0x100
-#define CXL_UPSTREAM_PORT_DVSEC_OFFSET \
+#define CXL_UPSTREAM_PORT_SN_OFFSET \
     (CXL_UPSTREAM_PORT_AER_OFFSET + PCI_ERR_SIZEOF)
+#define CXL_UPSTREAM_PORT_DVSEC_OFFSET \
+    (CXL_UPSTREAM_PORT_SN_OFFSET + PCI_EXT_CAP_DSN_SIZEOF)
 
 typedef struct CXLUpstreamPort {
     /*< private >*/
@@ -30,6 +37,7 @@ typedef struct CXLUpstreamPort {
     /*< public >*/
     CXLComponentState cxl_cstate;
     DOECap doe_cdat;
+    uint64_t sn;
 } CXLUpstreamPort;
 
 CXLComponentState *cxl_usp_to_cstate(CXLUpstreamPort *usp)
@@ -326,7 +334,9 @@ static void cxl_usp_realize(PCIDevice *d, Error **errp)
     if (rc) {
         goto err_cap;
     }
-
+    if (usp->sn != UI64_NULL) {
+        pcie_dev_ser_num_init(d, CXL_UPSTREAM_PORT_SN_OFFSET, usp->sn);
+    }
     cxl_cstate->dvsec_offset = CXL_UPSTREAM_PORT_DVSEC_OFFSET;
     cxl_cstate->pdev = d;
     build_dvsecs(cxl_cstate);
@@ -366,6 +376,7 @@ static void cxl_usp_exitfn(PCIDevice *d)
 }
 
 static Property cxl_upstream_props[] = {
+    DEFINE_PROP_UINT64("sn", CXLUpstreamPort, sn, UI64_NULL),
     DEFINE_PROP_STRING("cdat", CXLUpstreamPort, cxl_cstate.cdat.filename),
     DEFINE_PROP_END_OF_LIST()
 };
diff --git a/hw/pci/pci.c b/hw/pci/pci.c
index 881d774fb6..b0d21bf43a 100644
--- a/hw/pci/pci.c
+++ b/hw/pci/pci.c
@@ -893,7 +893,7 @@ static void pci_init_w1cmask(PCIDevice *dev)
 static void pci_init_mask_bridge(PCIDevice *d)
 {
     /* PCI_PRIMARY_BUS, PCI_SECONDARY_BUS, PCI_SUBORDINATE_BUS and
-       PCI_SEC_LETENCY_TIMER */
+       PCI_SEC_LATENCY_TIMER */
     memset(d->wmask + PCI_PRIMARY_BUS, 0xff, 4);
 
     /* base and limit */
diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index e7b9345615..6a4e38856d 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -38,6 +38,7 @@
 #include "qapi/error.h"
 #include "hw/acpi/acpi_aml_interface.h"
 #include "hw/acpi/pci.h"
+#include "hw/qdev-properties.h"
 
 /* PCI bridge subsystem vendor ID helper functions */
 #define PCI_SSVID_SIZEOF        8
@@ -385,6 +386,11 @@ void pci_bridge_initfn(PCIDevice *dev, const char *typename)
     pci_bridge_region_init(br);
     QLIST_INIT(&sec_bus->child);
     QLIST_INSERT_HEAD(&parent->child, sec_bus, sibling);
+
+    /* For express secondary buses, secondary latency timer is RO 0 */
+    if (pci_bus_is_express(sec_bus) && !br->pcie_writeable_slt_bug) {
+        dev->wmask[PCI_SEC_LATENCY_TIMER] = 0;
+    }
 }
 
 /* default qdev clean up function for PCI-to-PCI bridge */
@@ -466,10 +472,18 @@ int pci_bridge_qemu_reserve_cap_init(PCIDevice *dev, int cap_offset,
     return 0;
 }
 
+static Property pci_bridge_properties[] = {
+    DEFINE_PROP_BOOL("x-pci-express-writeable-slt-bug", PCIBridge,
+                     pcie_writeable_slt_bug, false),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
 static void pci_bridge_class_init(ObjectClass *klass, void *data)
 {
     AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(klass);
+    DeviceClass *k = DEVICE_CLASS(klass);
 
+    device_class_set_props(k, pci_bridge_properties);
     adevc->build_dev_aml = build_pci_bridge_aml;
 }
 
diff --git a/hw/pci/pcie_sriov.c b/hw/pci/pcie_sriov.c
index 76a3b6917e..5ef8950940 100644
--- a/hw/pci/pcie_sriov.c
+++ b/hw/pci/pcie_sriov.c
@@ -196,19 +196,16 @@ static void register_vfs(PCIDevice *dev)
 
 static void unregister_vfs(PCIDevice *dev)
 {
-    Error *local_err = NULL;
     uint16_t num_vfs = dev->exp.sriov_pf.num_vfs;
     uint16_t i;
 
     trace_sriov_unregister_vfs(dev->name, PCI_SLOT(dev->devfn),
                                PCI_FUNC(dev->devfn), num_vfs);
     for (i = 0; i < num_vfs; i++) {
+        Error *err = NULL;
         PCIDevice *vf = dev->exp.sriov_pf.vf[i];
-        object_property_set_bool(OBJECT(vf), "realized", false, &local_err);
-        if (local_err) {
-            fprintf(stderr, "Failed to unplug: %s\n",
-                    error_get_pretty(local_err));
-            error_free(local_err);
+        if (!object_property_set_bool(OBJECT(vf), "realized", false, &err)) {
+            error_reportf_err(err, "Failed to unplug: ");
         }
         object_unparent(OBJECT(vf));
         object_unref(OBJECT(vf));
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index ee99b19e7a..df6b66cc1a 100644
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -39,10 +39,6 @@ static const int user_feature_bits[] = {
     VHOST_INVALID_FEATURE_BIT
 };
 
-enum VhostUserProtocolFeature {
-    VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
-};
-
 static void vhost_user_scsi_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostUserSCSI *s = (VHostUserSCSI *)vdev;
diff --git a/hw/virtio/meson.build b/hw/virtio/meson.build
index 13e7c6c272..c0055a7832 100644
--- a/hw/virtio/meson.build
+++ b/hw/virtio/meson.build
@@ -1,27 +1,31 @@
-softmmu_virtio_ss = ss.source_set()
-softmmu_virtio_ss.add(files('virtio-bus.c'))
-softmmu_virtio_ss.add(when: 'CONFIG_VIRTIO_PCI', if_true: files('virtio-pci.c'))
-softmmu_virtio_ss.add(when: 'CONFIG_VIRTIO_MMIO', if_true: files('virtio-mmio.c'))
-softmmu_virtio_ss.add(when: 'CONFIG_VIRTIO_CRYPTO', if_true: files('virtio-crypto.c'))
-softmmu_virtio_ss.add(when: 'CONFIG_VHOST_VSOCK_COMMON', if_true: files('vhost-vsock-common.c'))
-softmmu_virtio_ss.add(when: 'CONFIG_VIRTIO_IOMMU', if_true: files('virtio-iommu.c'))
-softmmu_virtio_ss.add(when: 'CONFIG_VHOST_VDPA_DEV', if_true: files('vdpa-dev.c'))
+system_virtio_ss = ss.source_set()
+system_virtio_ss.add(files('virtio-bus.c'))
+system_virtio_ss.add(when: 'CONFIG_VIRTIO_PCI', if_true: files('virtio-pci.c'))
+system_virtio_ss.add(when: 'CONFIG_VIRTIO_MMIO', if_true: files('virtio-mmio.c'))
+system_virtio_ss.add(when: 'CONFIG_VIRTIO_CRYPTO', if_true: files('virtio-crypto.c'))
+system_virtio_ss.add(when: 'CONFIG_VHOST_VSOCK_COMMON', if_true: files('vhost-vsock-common.c'))
+system_virtio_ss.add(when: 'CONFIG_VIRTIO_IOMMU', if_true: files('virtio-iommu.c'))
+system_virtio_ss.add(when: 'CONFIG_VHOST_VDPA_DEV', if_true: files('vdpa-dev.c'))
 
 specific_virtio_ss = ss.source_set()
 specific_virtio_ss.add(files('virtio.c'))
 specific_virtio_ss.add(files('virtio-config-io.c', 'virtio-qmp.c'))
 
 if have_vhost
-  softmmu_virtio_ss.add(files('vhost.c'))
+  system_virtio_ss.add(files('vhost.c'))
   specific_virtio_ss.add(files('vhost-backend.c', 'vhost-iova-tree.c'))
   if have_vhost_user
+    # fixme - this really should be generic
     specific_virtio_ss.add(files('vhost-user.c'))
+    system_virtio_ss.add(files('vhost-user-device.c'))
+    system_virtio_ss.add(when: 'CONFIG_VIRTIO_PCI', if_true: files('vhost-user-device-pci.c'))
   endif
   if have_vhost_vdpa
-    specific_virtio_ss.add(files('vhost-vdpa.c', 'vhost-shadow-virtqueue.c'))
+    system_virtio_ss.add(files('vhost-vdpa.c'))
+    specific_virtio_ss.add(files('vhost-shadow-virtqueue.c'))
   endif
 else
-  softmmu_virtio_ss.add(files('vhost-stub.c'))
+  system_virtio_ss.add(files('vhost-stub.c'))
 endif
 
 specific_virtio_ss.add(when: 'CONFIG_VIRTIO_BALLOON', if_true: files('virtio-balloon.c'))
@@ -67,7 +71,7 @@ virtio_pci_ss.add(when: 'CONFIG_VIRTIO_MD', if_true: files('virtio-md-pci.c'))
 
 specific_virtio_ss.add_all(when: 'CONFIG_VIRTIO_PCI', if_true: virtio_pci_ss)
 
-system_ss.add_all(when: 'CONFIG_VIRTIO', if_true: softmmu_virtio_ss)
+system_ss.add_all(when: 'CONFIG_VIRTIO', if_true: system_virtio_ss)
 system_ss.add(when: 'CONFIG_VIRTIO', if_false: files('vhost-stub.c'))
 system_ss.add(when: 'CONFIG_VIRTIO', if_false: files('virtio-stub.c'))
 system_ss.add(when: 'CONFIG_ALL', if_true: files('vhost-stub.c'))
diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
index 7109cf1a3b..1cb9027d1e 100644
--- a/hw/virtio/trace-events
+++ b/hw/virtio/trace-events
@@ -48,7 +48,7 @@ vhost_vdpa_set_features(void *dev, uint64_t features) "dev: %p features: 0x%"PRI
 vhost_vdpa_get_device_id(void *dev, uint32_t device_id) "dev: %p device_id %"PRIu32
 vhost_vdpa_reset_device(void *dev) "dev: %p"
 vhost_vdpa_get_vq_index(void *dev, int idx, int vq_idx) "dev: %p idx: %d vq idx: %d"
-vhost_vdpa_set_vring_ready(void *dev) "dev: %p"
+vhost_vdpa_set_vring_ready(void *dev, unsigned i, int r) "dev: %p, idx: %u, r: %d"
 vhost_vdpa_dump_config(void *dev, const char *line) "dev: %p %s"
 vhost_vdpa_set_config(void *dev, uint32_t offset, uint32_t size, uint32_t flags) "dev: %p offset: %"PRIu32" size: %"PRIu32" flags: 0x%"PRIx32
 vhost_vdpa_get_config(void *dev, void *config, uint32_t config_len) "dev: %p config: %p config_len: %"PRIu32
diff --git a/hw/virtio/vdpa-dev.c b/hw/virtio/vdpa-dev.c
index 363b625243..f22d5d5bc0 100644
--- a/hw/virtio/vdpa-dev.c
+++ b/hw/virtio/vdpa-dev.c
@@ -255,6 +255,9 @@ static int vhost_vdpa_device_start(VirtIODevice *vdev, Error **errp)
         error_setg_errno(errp, -ret, "Error starting vhost");
         goto err_guest_notifiers;
     }
+    for (i = 0; i < s->dev.nvqs; ++i) {
+        vhost_vdpa_set_vring_ready(&s->vdpa, i);
+    }
     s->started = true;
 
     /*
diff --git a/hw/virtio/vhost-shadow-virtqueue.c b/hw/virtio/vhost-shadow-virtqueue.c
index 49e5aed931..e731b1d2ea 100644
--- a/hw/virtio/vhost-shadow-virtqueue.c
+++ b/hw/virtio/vhost-shadow-virtqueue.c
@@ -514,29 +514,37 @@ static void vhost_svq_flush(VhostShadowVirtqueue *svq,
 }
 
 /**
- * Poll the SVQ for one device used buffer.
+ * Poll the SVQ to wait for the device to use the specified number
+ * of elements and return the total length written by the device.
  *
  * This function race with main event loop SVQ polling, so extra
  * synchronization is needed.
  *
- * Return the length written by the device.
+ * @svq: The svq
+ * @num: The number of elements that need to be used
  */
-size_t vhost_svq_poll(VhostShadowVirtqueue *svq)
+size_t vhost_svq_poll(VhostShadowVirtqueue *svq, size_t num)
 {
-    int64_t start_us = g_get_monotonic_time();
-    uint32_t len = 0;
+    size_t len = 0;
+    uint32_t r;
 
-    do {
-        if (vhost_svq_more_used(svq)) {
-            break;
-        }
+    while (num--) {
+        int64_t start_us = g_get_monotonic_time();
 
-        if (unlikely(g_get_monotonic_time() - start_us > 10e6)) {
-            return 0;
-        }
-    } while (true);
+        do {
+            if (vhost_svq_more_used(svq)) {
+                break;
+            }
+
+            if (unlikely(g_get_monotonic_time() - start_us > 10e6)) {
+                return len;
+            }
+        } while (true);
+
+        vhost_svq_get_buf(svq, &r);
+        len += r;
+    }
 
-    vhost_svq_get_buf(svq, &len);
     return len;
 }
 
diff --git a/hw/virtio/vhost-shadow-virtqueue.h b/hw/virtio/vhost-shadow-virtqueue.h
index 6efe051a70..5bce67837b 100644
--- a/hw/virtio/vhost-shadow-virtqueue.h
+++ b/hw/virtio/vhost-shadow-virtqueue.h
@@ -119,7 +119,7 @@ void vhost_svq_push_elem(VhostShadowVirtqueue *svq,
 int vhost_svq_add(VhostShadowVirtqueue *svq, const struct iovec *out_sg,
                   size_t out_num, const struct iovec *in_sg, size_t in_num,
                   VirtQueueElement *elem);
-size_t vhost_svq_poll(VhostShadowVirtqueue *svq);
+size_t vhost_svq_poll(VhostShadowVirtqueue *svq, size_t num);
 
 void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick_fd);
 void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd);
diff --git a/hw/virtio/vhost-user-device-pci.c b/hw/virtio/vhost-user-device-pci.c
new file mode 100644
index 0000000000..41f9b7905b
--- /dev/null
+++ b/hw/virtio/vhost-user-device-pci.c
@@ -0,0 +1,71 @@
+/*
+ * Vhost-user generic virtio device PCI glue
+ *
+ * Copyright (c) 2023 Linaro Ltd
+ * Author: Alex Bennée <alex.bennee@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/vhost-user-device.h"
+#include "hw/virtio/virtio-pci.h"
+
+struct VHostUserDevicePCI {
+    VirtIOPCIProxy parent_obj;
+    VHostUserBase vub;
+};
+
+typedef struct VHostUserDevicePCI VHostUserDevicePCI;
+
+#define TYPE_VHOST_USER_DEVICE_PCI "vhost-user-device-pci-base"
+
+DECLARE_INSTANCE_CHECKER(VHostUserDevicePCI,
+                         VHOST_USER_DEVICE_PCI,
+                         TYPE_VHOST_USER_DEVICE_PCI)
+
+static void vhost_user_device_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
+{
+    VHostUserDevicePCI *dev = VHOST_USER_DEVICE_PCI(vpci_dev);
+    DeviceState *vdev = DEVICE(&dev->vub);
+
+    vpci_dev->nvectors = 1;
+    qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
+}
+
+static void vhost_user_device_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_device_pci_realize;
+    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+    pcidev_k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
+    pcidev_k->device_id = 0; /* Set by virtio-pci based on virtio id */
+    pcidev_k->revision = 0x00;
+    pcidev_k->class_id = PCI_CLASS_COMMUNICATION_OTHER;
+}
+
+static void vhost_user_device_pci_instance_init(Object *obj)
+{
+    VHostUserDevicePCI *dev = VHOST_USER_DEVICE_PCI(obj);
+
+    virtio_instance_init_common(obj, &dev->vub, sizeof(dev->vub),
+                                TYPE_VHOST_USER_DEVICE);
+}
+
+static const VirtioPCIDeviceTypeInfo vhost_user_device_pci_info = {
+    .base_name = TYPE_VHOST_USER_DEVICE_PCI,
+    .non_transitional_name = "vhost-user-device-pci",
+    .instance_size = sizeof(VHostUserDevicePCI),
+    .instance_init = vhost_user_device_pci_instance_init,
+    .class_init = vhost_user_device_pci_class_init,
+};
+
+static void vhost_user_device_pci_register(void)
+{
+    virtio_pci_types_register(&vhost_user_device_pci_info);
+}
+
+type_init(vhost_user_device_pci_register);
diff --git a/hw/virtio/vhost-user-device.c b/hw/virtio/vhost-user-device.c
new file mode 100644
index 0000000000..2b028cae08
--- /dev/null
+++ b/hw/virtio/vhost-user-device.c
@@ -0,0 +1,380 @@
+/*
+ * Generic vhost-user stub. This can be used to connect to any
+ * vhost-user backend. All configuration details must be handled by
+ * the vhost-user daemon itself
+ *
+ * Copyright (c) 2023 Linaro Ltd
+ * Author: Alex Bennée <alex.bennee@linaro.org>
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/qdev-properties.h"
+#include "hw/virtio/virtio-bus.h"
+#include "hw/virtio/vhost-user-device.h"
+#include "qemu/error-report.h"
+
+static void vub_start(VirtIODevice *vdev)
+{
+    BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
+    VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+    int ret, i;
+
+    if (!k->set_guest_notifiers) {
+        error_report("binding does not support guest notifiers");
+        return;
+    }
+
+    ret = vhost_dev_enable_notifiers(&vub->vhost_dev, vdev);
+    if (ret < 0) {
+        error_report("Error enabling host notifiers: %d", -ret);
+        return;
+    }
+
+    ret = k->set_guest_notifiers(qbus->parent, vub->vhost_dev.nvqs, true);
+    if (ret < 0) {
+        error_report("Error binding guest notifier: %d", -ret);
+        goto err_host_notifiers;
+    }
+
+    vub->vhost_dev.acked_features = vdev->guest_features;
+
+    ret = vhost_dev_start(&vub->vhost_dev, vdev, true);
+    if (ret < 0) {
+        error_report("Error starting vhost-user-device: %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 < vub->vhost_dev.nvqs; i++) {
+        vhost_virtqueue_mask(&vub->vhost_dev, vdev, i, false);
+    }
+
+    return;
+
+err_guest_notifiers:
+    k->set_guest_notifiers(qbus->parent, vub->vhost_dev.nvqs, false);
+err_host_notifiers:
+    vhost_dev_disable_notifiers(&vub->vhost_dev, vdev);
+}
+
+static void vub_stop(VirtIODevice *vdev)
+{
+    VHostUserBase *vub = VHOST_USER_BASE(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(&vub->vhost_dev, vdev, true);
+
+    ret = k->set_guest_notifiers(qbus->parent, vub->vhost_dev.nvqs, false);
+    if (ret < 0) {
+        error_report("vhost guest notifier cleanup failed: %d", ret);
+        return;
+    }
+
+    vhost_dev_disable_notifiers(&vub->vhost_dev, vdev);
+}
+
+static void vub_set_status(VirtIODevice *vdev, uint8_t status)
+{
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+    bool should_start = virtio_device_should_start(vdev, status);
+
+    if (vhost_dev_is_started(&vub->vhost_dev) == should_start) {
+        return;
+    }
+
+    if (should_start) {
+        vub_start(vdev);
+    } else {
+        vub_stop(vdev);
+    }
+}
+
+/*
+ * For an implementation where everything is delegated to the backend
+ * we don't do anything other than return the full feature set offered
+ * by the daemon (module the reserved feature bit).
+ */
+static uint64_t vub_get_features(VirtIODevice *vdev,
+                                 uint64_t requested_features, Error **errp)
+{
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+    /* This should be set when the vhost connection initialises */
+    g_assert(vub->vhost_dev.features);
+    return vub->vhost_dev.features & ~(1ULL << VHOST_USER_F_PROTOCOL_FEATURES);
+}
+
+/*
+ * To handle VirtIO config we need to know the size of the config
+ * space. We don't cache the config but re-fetch it from the guest
+ * every time in case something has changed.
+ */
+static void vub_get_config(VirtIODevice *vdev, uint8_t *config)
+{
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+    Error *local_err = NULL;
+
+    /*
+     * There will have been a warning during vhost_dev_init, but lets
+     * assert here as nothing will go right now.
+     */
+    g_assert(vub->config_size && vub->vhost_user.supports_config == true);
+
+    if (vhost_dev_get_config(&vub->vhost_dev, config,
+                             vub->config_size, &local_err)) {
+        error_report_err(local_err);
+    }
+}
+
+/*
+ * When the daemon signals an update to the config we just need to
+ * signal the guest as we re-read the config on demand above.
+ */
+static int vub_config_notifier(struct vhost_dev *dev)
+{
+    virtio_notify_config(dev->vdev);
+    return 0;
+}
+
+const VhostDevConfigOps vub_config_ops = {
+    .vhost_dev_config_notifier = vub_config_notifier,
+};
+
+static void vub_handle_output(VirtIODevice *vdev, VirtQueue *vq)
+{
+    /*
+     * Not normally called; it's the daemon that handles the queue;
+     * however virtio's cleanup path can call this.
+     */
+}
+
+static void do_vhost_user_cleanup(VirtIODevice *vdev, VHostUserBase *vub)
+{
+    vhost_user_cleanup(&vub->vhost_user);
+
+    for (int i = 0; i < vub->num_vqs; i++) {
+        VirtQueue *vq = g_ptr_array_index(vub->vqs, i);
+        virtio_delete_queue(vq);
+    }
+
+    virtio_cleanup(vdev);
+}
+
+static int vub_connect(DeviceState *dev)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+    struct vhost_dev *vhost_dev = &vub->vhost_dev;
+
+    if (vub->connected) {
+        return 0;
+    }
+    vub->connected = true;
+
+    /*
+     * If we support VHOST_USER_GET_CONFIG we must enable the notifier
+     * so we can ping the guest when it updates.
+     */
+    if (vub->vhost_user.supports_config) {
+        vhost_dev_set_config_notifier(vhost_dev, &vub_config_ops);
+    }
+
+    /* restore vhost state */
+    if (virtio_device_started(vdev, vdev->status)) {
+        vub_start(vdev);
+    }
+
+    return 0;
+}
+
+static void vub_disconnect(DeviceState *dev)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+
+    if (!vub->connected) {
+        return;
+    }
+    vub->connected = false;
+
+    if (vhost_dev_is_started(&vub->vhost_dev)) {
+        vub_stop(vdev);
+    }
+}
+
+static void vub_event(void *opaque, QEMUChrEvent event)
+{
+    DeviceState *dev = opaque;
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserBase *vub = VHOST_USER_BASE(vdev);
+
+    switch (event) {
+    case CHR_EVENT_OPENED:
+        if (vub_connect(dev) < 0) {
+            qemu_chr_fe_disconnect(&vub->chardev);
+            return;
+        }
+        break;
+    case CHR_EVENT_CLOSED:
+        vub_disconnect(dev);
+        break;
+    case CHR_EVENT_BREAK:
+    case CHR_EVENT_MUX_IN:
+    case CHR_EVENT_MUX_OUT:
+        /* Ignore */
+        break;
+    }
+}
+
+static void vub_device_realize(DeviceState *dev, Error **errp)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserBase *vub = VHOST_USER_BASE(dev);
+    int ret;
+
+    if (!vub->chardev.chr) {
+        error_setg(errp, "vhost-user-device: missing chardev");
+        return;
+    }
+
+    if (!vub->virtio_id) {
+        error_setg(errp, "vhost-user-device: need to define device id");
+        return;
+    }
+
+    if (!vub->num_vqs) {
+        vub->num_vqs = 1; /* reasonable default? */
+    }
+
+    /*
+     * We can't handle config requests unless we know the size of the
+     * config region, specialisations of the vhost-user-device will be
+     * able to set this.
+     */
+    if (vub->config_size) {
+        vub->vhost_user.supports_config = true;
+    }
+
+    if (!vhost_user_init(&vub->vhost_user, &vub->chardev, errp)) {
+        return;
+    }
+
+    virtio_init(vdev, vub->virtio_id, vub->config_size);
+
+    /*
+     * Disable guest notifiers, by default all notifications will be via the
+     * asynchronous vhost-user socket.
+     */
+    vdev->use_guest_notifier_mask = false;
+
+    /* Allocate queues */
+    vub->vqs = g_ptr_array_sized_new(vub->num_vqs);
+    for (int i = 0; i < vub->num_vqs; i++) {
+        g_ptr_array_add(vub->vqs,
+                        virtio_add_queue(vdev, 4, vub_handle_output));
+    }
+
+    vub->vhost_dev.nvqs = vub->num_vqs;
+    vub->vhost_dev.vqs = g_new0(struct vhost_virtqueue, vub->vhost_dev.nvqs);
+
+    /* connect to backend */
+    ret = vhost_dev_init(&vub->vhost_dev, &vub->vhost_user,
+                         VHOST_BACKEND_TYPE_USER, 0, errp);
+
+    if (ret < 0) {
+        do_vhost_user_cleanup(vdev, vub);
+    }
+
+    qemu_chr_fe_set_handlers(&vub->chardev, NULL, NULL, vub_event, NULL,
+                             dev, NULL, true);
+}
+
+static void vub_device_unrealize(DeviceState *dev)
+{
+    VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+    VHostUserBase *vub = VHOST_USER_BASE(dev);
+    struct vhost_virtqueue *vhost_vqs = vub->vhost_dev.vqs;
+
+    /* This will stop vhost backend if appropriate. */
+    vub_set_status(vdev, 0);
+    vhost_dev_cleanup(&vub->vhost_dev);
+    g_free(vhost_vqs);
+    do_vhost_user_cleanup(vdev, vub);
+}
+
+static void vub_class_init(ObjectClass *klass, void *data)
+{
+    VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
+
+    vdc->realize = vub_device_realize;
+    vdc->unrealize = vub_device_unrealize;
+    vdc->get_features = vub_get_features;
+    vdc->get_config = vub_get_config;
+    vdc->set_status = vub_set_status;
+}
+
+static const TypeInfo vub_info = {
+    .name = TYPE_VHOST_USER_BASE,
+    .parent = TYPE_VIRTIO_DEVICE,
+    .instance_size = sizeof(VHostUserBase),
+    .class_init = vub_class_init,
+    .class_size = sizeof(VHostUserBaseClass),
+    .abstract = true
+};
+
+
+/*
+ * The following is a concrete implementation of the base class which
+ * allows the user to define the key parameters via the command line.
+ */
+
+static const VMStateDescription vud_vmstate = {
+    .name = "vhost-user-device",
+    .unmigratable = 1,
+};
+
+static Property vud_properties[] = {
+    DEFINE_PROP_CHR("chardev", VHostUserBase, chardev),
+    DEFINE_PROP_UINT16("virtio-id", VHostUserBase, virtio_id, 0),
+    DEFINE_PROP_UINT32("num_vqs", VHostUserBase, num_vqs, 1),
+    DEFINE_PROP_UINT32("config_size", VHostUserBase, config_size, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void vud_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    device_class_set_props(dc, vud_properties);
+    dc->vmsd = &vud_vmstate;
+    set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
+}
+
+static const TypeInfo vud_info = {
+    .name = TYPE_VHOST_USER_DEVICE,
+    .parent = TYPE_VHOST_USER_BASE,
+    .instance_size = sizeof(VHostUserBase),
+    .class_init = vud_class_init,
+    .class_size = sizeof(VHostUserBaseClass),
+};
+
+static void vu_register_types(void)
+{
+    type_register_static(&vub_info);
+    type_register_static(&vud_info);
+}
+
+type_init(vu_register_types)
diff --git a/hw/virtio/vhost-user-gpio.c b/hw/virtio/vhost-user-gpio.c
index 3b013f2d0f..3d7fae3984 100644
--- a/hw/virtio/vhost-user-gpio.c
+++ b/hw/virtio/vhost-user-gpio.c
@@ -205,6 +205,12 @@ static void vu_gpio_guest_notifier_mask(VirtIODevice *vdev, int idx, bool mask)
     vhost_virtqueue_mask(&gpio->vhost_dev, vdev, idx, mask);
 }
 
+static struct vhost_dev *vu_gpio_get_vhost(VirtIODevice *vdev)
+{
+    VHostUserGPIO *gpio = VHOST_USER_GPIO(vdev);
+    return &gpio->vhost_dev;
+}
+
 static void do_vhost_user_cleanup(VirtIODevice *vdev, VHostUserGPIO *gpio)
 {
     virtio_delete_queue(gpio->command_vq);
@@ -413,6 +419,7 @@ static void vu_gpio_class_init(ObjectClass *klass, void *data)
     vdc->get_config = vu_gpio_get_config;
     vdc->set_status = vu_gpio_set_status;
     vdc->guest_notifier_mask = vu_gpio_guest_notifier_mask;
+    vdc->get_vhost = vu_gpio_get_vhost;
 }
 
 static const TypeInfo vu_gpio_info = {
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 8dcf049d42..3766b415f8 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -10,6 +10,7 @@
 
 #include "qemu/osdep.h"
 #include "qapi/error.h"
+#include "hw/virtio/virtio-dmabuf.h"
 #include "hw/virtio/vhost.h"
 #include "hw/virtio/virtio-crypto.h"
 #include "hw/virtio/vhost-user.h"
@@ -21,6 +22,7 @@
 #include "sysemu/kvm.h"
 #include "qemu/error-report.h"
 #include "qemu/main-loop.h"
+#include "qemu/uuid.h"
 #include "qemu/sockets.h"
 #include "sysemu/runstate.h"
 #include "sysemu/cryptodev.h"
@@ -56,27 +58,6 @@
  */
 #define VHOST_USER_MAX_CONFIG_SIZE 256
 
-enum VhostUserProtocolFeature {
-    VHOST_USER_PROTOCOL_F_MQ = 0,
-    VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
-    VHOST_USER_PROTOCOL_F_RARP = 2,
-    VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
-    VHOST_USER_PROTOCOL_F_NET_MTU = 4,
-    VHOST_USER_PROTOCOL_F_BACKEND_REQ = 5,
-    VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
-    VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
-    VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
-    VHOST_USER_PROTOCOL_F_CONFIG = 9,
-    VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD = 10,
-    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_STATUS = 16,
-    VHOST_USER_PROTOCOL_F_MAX
-};
-
 #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
 
 typedef enum VhostUserRequest {
@@ -121,6 +102,7 @@ typedef enum VhostUserRequest {
     VHOST_USER_REM_MEM_REG = 38,
     VHOST_USER_SET_STATUS = 39,
     VHOST_USER_GET_STATUS = 40,
+    VHOST_USER_GET_SHARED_OBJECT = 41,
     VHOST_USER_MAX
 } VhostUserRequest;
 
@@ -129,6 +111,9 @@ typedef enum VhostUserBackendRequest {
     VHOST_USER_BACKEND_IOTLB_MSG = 1,
     VHOST_USER_BACKEND_CONFIG_CHANGE_MSG = 2,
     VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG = 3,
+    VHOST_USER_BACKEND_SHARED_OBJECT_ADD = 6,
+    VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE = 7,
+    VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP = 8,
     VHOST_USER_BACKEND_MAX
 }  VhostUserBackendRequest;
 
@@ -202,6 +187,10 @@ typedef struct VhostUserInflight {
     uint16_t queue_size;
 } VhostUserInflight;
 
+typedef struct VhostUserShared {
+    unsigned char uuid[16];
+} VhostUserShared;
+
 typedef struct {
     VhostUserRequest request;
 
@@ -226,6 +215,7 @@ typedef union {
         VhostUserCryptoSession session;
         VhostUserVringArea area;
         VhostUserInflight inflight;
+        VhostUserShared object;
 } VhostUserPayload;
 
 typedef struct VhostUserMsg {
@@ -1601,6 +1591,139 @@ static int vhost_user_backend_handle_vring_host_notifier(struct vhost_dev *dev,
     return 0;
 }
 
+static int
+vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev,
+                                            VhostUserShared *object)
+{
+    QemuUUID uuid;
+
+    memcpy(uuid.data, object->uuid, sizeof(object->uuid));
+    return virtio_add_vhost_device(&uuid, dev);
+}
+
+static int
+vhost_user_backend_handle_shared_object_remove(VhostUserShared *object)
+{
+    QemuUUID uuid;
+
+    memcpy(uuid.data, object->uuid, sizeof(object->uuid));
+    return virtio_remove_resource(&uuid);
+}
+
+static bool vhost_user_send_resp(QIOChannel *ioc, VhostUserHeader *hdr,
+                                 VhostUserPayload *payload, Error **errp)
+{
+    struct iovec iov[] = {
+        { .iov_base = hdr,      .iov_len = VHOST_USER_HDR_SIZE },
+        { .iov_base = payload,  .iov_len = hdr->size },
+    };
+
+    hdr->flags &= ~VHOST_USER_NEED_REPLY_MASK;
+    hdr->flags |= VHOST_USER_REPLY_MASK;
+
+    return !qio_channel_writev_all(ioc, iov, ARRAY_SIZE(iov), errp);
+}
+
+static bool
+vhost_user_backend_send_dmabuf_fd(QIOChannel *ioc, VhostUserHeader *hdr,
+                                  VhostUserPayload *payload, Error **errp)
+{
+    hdr->size = sizeof(payload->u64);
+    return vhost_user_send_resp(ioc, hdr, payload, errp);
+}
+
+int vhost_user_get_shared_object(struct vhost_dev *dev, unsigned char *uuid,
+                                 int *dmabuf_fd)
+{
+    struct vhost_user *u = dev->opaque;
+    CharBackend *chr = u->user->chr;
+    int ret;
+    VhostUserMsg msg = {
+        .hdr.request = VHOST_USER_GET_SHARED_OBJECT,
+        .hdr.flags = VHOST_USER_VERSION,
+    };
+    memcpy(msg.payload.object.uuid, uuid, sizeof(msg.payload.object.uuid));
+
+    ret = vhost_user_write(dev, &msg, NULL, 0);
+    if (ret < 0) {
+        return ret;
+    }
+
+    ret = vhost_user_read(dev, &msg);
+    if (ret < 0) {
+        return ret;
+    }
+
+    if (msg.hdr.request != VHOST_USER_GET_SHARED_OBJECT) {
+        error_report("Received unexpected msg type. "
+                     "Expected %d received %d",
+                     VHOST_USER_GET_SHARED_OBJECT, msg.hdr.request);
+        return -EPROTO;
+    }
+
+    *dmabuf_fd = qemu_chr_fe_get_msgfd(chr);
+    if (*dmabuf_fd < 0) {
+        error_report("Failed to get dmabuf fd");
+        return -EIO;
+    }
+
+    return 0;
+}
+
+static int
+vhost_user_backend_handle_shared_object_lookup(struct vhost_user *u,
+                                               QIOChannel *ioc,
+                                               VhostUserHeader *hdr,
+                                               VhostUserPayload *payload)
+{
+    QemuUUID uuid;
+    CharBackend *chr = u->user->chr;
+    Error *local_err = NULL;
+    int dmabuf_fd = -1;
+    int fd_num = 0;
+
+    memcpy(uuid.data, payload->object.uuid, sizeof(payload->object.uuid));
+
+    payload->u64 = 0;
+    switch (virtio_object_type(&uuid)) {
+    case TYPE_DMABUF:
+        dmabuf_fd = virtio_lookup_dmabuf(&uuid);
+        break;
+    case TYPE_VHOST_DEV:
+    {
+        struct vhost_dev *dev = virtio_lookup_vhost_device(&uuid);
+        if (dev == NULL) {
+            payload->u64 = -EINVAL;
+            break;
+        }
+        int ret = vhost_user_get_shared_object(dev, uuid.data, &dmabuf_fd);
+        if (ret < 0) {
+            payload->u64 = ret;
+        }
+        break;
+    }
+    case TYPE_INVALID:
+        payload->u64 = -EINVAL;
+        break;
+    }
+
+    if (dmabuf_fd != -1) {
+        fd_num++;
+    }
+
+    if (qemu_chr_fe_set_msgfds(chr, &dmabuf_fd, fd_num) < 0) {
+        error_report("Failed to set msg fds.");
+        payload->u64 = -EINVAL;
+    }
+
+    if (!vhost_user_backend_send_dmabuf_fd(ioc, hdr, payload, &local_err)) {
+        error_report_err(local_err);
+        return -EINVAL;
+    }
+
+    return 0;
+}
+
 static void close_backend_channel(struct vhost_user *u)
 {
     g_source_destroy(u->backend_src);
@@ -1658,6 +1781,16 @@ static gboolean backend_read(QIOChannel *ioc, GIOCondition condition,
         ret = vhost_user_backend_handle_vring_host_notifier(dev, &payload.area,
                                                           fd ? fd[0] : -1);
         break;
+    case VHOST_USER_BACKEND_SHARED_OBJECT_ADD:
+        ret = vhost_user_backend_handle_shared_object_add(dev, &payload.object);
+        break;
+    case VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE:
+        ret = vhost_user_backend_handle_shared_object_remove(&payload.object);
+        break;
+    case VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP:
+        ret = vhost_user_backend_handle_shared_object_lookup(dev->opaque, ioc,
+                                                             &hdr, &payload);
+        break;
     default:
         error_report("Received unexpected msg type: %d.", hdr.request);
         ret = -EINVAL;
@@ -1668,21 +1801,10 @@ static gboolean backend_read(QIOChannel *ioc, GIOCondition condition,
      * directly in their request handlers.
      */
     if (hdr.flags & VHOST_USER_NEED_REPLY_MASK) {
-        struct iovec iovec[2];
-
-
-        hdr.flags &= ~VHOST_USER_NEED_REPLY_MASK;
-        hdr.flags |= VHOST_USER_REPLY_MASK;
-
         payload.u64 = !!ret;
         hdr.size = sizeof(payload.u64);
 
-        iovec[0].iov_base = &hdr;
-        iovec[0].iov_len = VHOST_USER_HDR_SIZE;
-        iovec[1].iov_base = &payload;
-        iovec[1].iov_len = hdr.size;
-
-        if (qio_channel_writev_all(ioc, iovec, ARRAY_SIZE(iovec), &local_err)) {
+        if (!vhost_user_send_resp(ioc, &hdr, &payload, &local_err)) {
             error_report_err(local_err);
             goto err;
         }
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 42f2a4bae9..89ff02a999 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -14,6 +14,7 @@
 #include <linux/vfio.h>
 #include <sys/eventfd.h>
 #include <sys/ioctl.h>
+#include "exec/target_page.h"
 #include "hw/virtio/vhost.h"
 #include "hw/virtio/vhost-backend.h"
 #include "hw/virtio/virtio-net.h"
@@ -23,7 +24,6 @@
 #include "migration/blocker.h"
 #include "qemu/cutils.h"
 #include "qemu/main-loop.h"
-#include "cpu.h"
 #include "trace.h"
 #include "qapi/error.h"
 
@@ -31,18 +31,20 @@
  * Return one past the end of the end of section. Be careful with uint64_t
  * conversions!
  */
-static Int128 vhost_vdpa_section_end(const MemoryRegionSection *section)
+static Int128 vhost_vdpa_section_end(const MemoryRegionSection *section,
+                                     int page_mask)
 {
     Int128 llend = int128_make64(section->offset_within_address_space);
     llend = int128_add(llend, section->size);
-    llend = int128_and(llend, int128_exts64(TARGET_PAGE_MASK));
+    llend = int128_and(llend, int128_exts64(page_mask));
 
     return llend;
 }
 
 static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
                                                 uint64_t iova_min,
-                                                uint64_t iova_max)
+                                                uint64_t iova_max,
+                                                int page_mask)
 {
     Int128 llend;
 
@@ -68,7 +70,7 @@ static bool vhost_vdpa_listener_skipped_section(MemoryRegionSection *section,
      */
 
     if (!memory_region_is_iommu(section->mr)) {
-        llend = vhost_vdpa_section_end(section);
+        llend = vhost_vdpa_section_end(section, page_mask);
         if (int128_gt(llend, int128_make64(iova_max))) {
             error_report("RAM section out of device range (max=0x%" PRIx64
                          ", end addr=0x%" PRIx64 ")",
@@ -311,9 +313,11 @@ static void vhost_vdpa_listener_region_add(MemoryListener *listener,
     Int128 llend, llsize;
     void *vaddr;
     int ret;
+    int page_size = qemu_target_page_size();
+    int page_mask = -page_size;
 
     if (vhost_vdpa_listener_skipped_section(section, v->iova_range.first,
-                                            v->iova_range.last)) {
+                                            v->iova_range.last, page_mask)) {
         return;
     }
     if (memory_region_is_iommu(section->mr)) {
@@ -321,16 +325,16 @@ static void vhost_vdpa_listener_region_add(MemoryListener *listener,
         return;
     }
 
-    if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
-                 (section->offset_within_region & ~TARGET_PAGE_MASK))) {
+    if (unlikely((section->offset_within_address_space & ~page_mask) !=
+                 (section->offset_within_region & ~page_mask))) {
         trace_vhost_vdpa_listener_region_add_unaligned(v, section->mr->name,
-                       section->offset_within_address_space & ~TARGET_PAGE_MASK,
-                       section->offset_within_region & ~TARGET_PAGE_MASK);
+                       section->offset_within_address_space & ~page_mask,
+                       section->offset_within_region & ~page_mask);
         return;
     }
 
-    iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
-    llend = vhost_vdpa_section_end(section);
+    iova = ROUND_UP(section->offset_within_address_space, page_size);
+    llend = vhost_vdpa_section_end(section, page_mask);
     if (int128_ge(int128_make64(iova), llend)) {
         return;
     }
@@ -396,25 +400,27 @@ static void vhost_vdpa_listener_region_del(MemoryListener *listener,
     hwaddr iova;
     Int128 llend, llsize;
     int ret;
+    int page_size = qemu_target_page_size();
+    int page_mask = -page_size;
 
     if (vhost_vdpa_listener_skipped_section(section, v->iova_range.first,
-                                            v->iova_range.last)) {
+                                            v->iova_range.last, page_mask)) {
         return;
     }
     if (memory_region_is_iommu(section->mr)) {
         vhost_vdpa_iommu_region_del(listener, section);
     }
 
-    if (unlikely((section->offset_within_address_space & ~TARGET_PAGE_MASK) !=
-                 (section->offset_within_region & ~TARGET_PAGE_MASK))) {
+    if (unlikely((section->offset_within_address_space & ~page_mask) !=
+                 (section->offset_within_region & ~page_mask))) {
         trace_vhost_vdpa_listener_region_del_unaligned(v, section->mr->name,
-                       section->offset_within_address_space & ~TARGET_PAGE_MASK,
-                       section->offset_within_region & ~TARGET_PAGE_MASK);
+                       section->offset_within_address_space & ~page_mask,
+                       section->offset_within_region & ~page_mask);
         return;
     }
 
-    iova = TARGET_PAGE_ALIGN(section->offset_within_address_space);
-    llend = vhost_vdpa_section_end(section);
+    iova = ROUND_UP(section->offset_within_address_space, page_size);
+    llend = vhost_vdpa_section_end(section, page_mask);
 
     trace_vhost_vdpa_listener_region_del(v, iova,
         int128_get64(int128_sub(llend, int128_one())));
@@ -876,18 +882,17 @@ static int vhost_vdpa_get_vq_index(struct vhost_dev *dev, int idx)
     return idx;
 }
 
-static int vhost_vdpa_set_vring_ready(struct vhost_dev *dev)
+int vhost_vdpa_set_vring_ready(struct vhost_vdpa *v, unsigned idx)
 {
-    int i;
-    trace_vhost_vdpa_set_vring_ready(dev);
-    for (i = 0; i < dev->nvqs; ++i) {
-        struct vhost_vring_state state = {
-            .index = dev->vq_index + i,
-            .num = 1,
-        };
-        vhost_vdpa_call(dev, VHOST_VDPA_SET_VRING_ENABLE, &state);
-    }
-    return 0;
+    struct vhost_dev *dev = v->dev;
+    struct vhost_vring_state state = {
+        .index = idx,
+        .num = 1,
+    };
+    int r = vhost_vdpa_call(dev, VHOST_VDPA_SET_VRING_ENABLE, &state);
+
+    trace_vhost_vdpa_set_vring_ready(dev, idx, r);
+    return r;
 }
 
 static int vhost_vdpa_set_config_call(struct vhost_dev *dev,
@@ -1298,7 +1303,6 @@ static int vhost_vdpa_dev_start(struct vhost_dev *dev, bool started)
         if (unlikely(!ok)) {
             return -1;
         }
-        vhost_vdpa_set_vring_ready(dev);
     } else {
         vhost_vdpa_suspend(dev);
         vhost_vdpa_svqs_stop(dev);
diff --git a/hw/virtio/virtio-qmp.c b/hw/virtio/virtio-qmp.c
index 7515b0947b..1dd96ed20f 100644
--- a/hw/virtio/virtio-qmp.c
+++ b/hw/virtio/virtio-qmp.c
@@ -17,6 +17,7 @@
 #include "qapi/qapi-commands-qom.h"
 #include "qapi/qmp/qobject.h"
 #include "qapi/qmp/qjson.h"
+#include "hw/virtio/vhost-user.h"
 
 #include "standard-headers/linux/virtio_ids.h"
 #include "standard-headers/linux/vhost_types.h"
@@ -30,32 +31,13 @@
 #include "standard-headers/linux/virtio_iommu.h"
 #include "standard-headers/linux/virtio_mem.h"
 #include "standard-headers/linux/virtio_vsock.h"
+#include "standard-headers/linux/virtio_gpio.h"
 
 #include CONFIG_DEVICES
 
 #define FEATURE_ENTRY(name, desc) (qmp_virtio_feature_map_t) \
     { .virtio_bit = name, .feature_desc = desc }
 
-enum VhostUserProtocolFeature {
-    VHOST_USER_PROTOCOL_F_MQ = 0,
-    VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
-    VHOST_USER_PROTOCOL_F_RARP = 2,
-    VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
-    VHOST_USER_PROTOCOL_F_NET_MTU = 4,
-    VHOST_USER_PROTOCOL_F_BACKEND_REQ = 5,
-    VHOST_USER_PROTOCOL_F_CROSS_ENDIAN = 6,
-    VHOST_USER_PROTOCOL_F_CRYPTO_SESSION = 7,
-    VHOST_USER_PROTOCOL_F_PAGEFAULT = 8,
-    VHOST_USER_PROTOCOL_F_CONFIG = 9,
-    VHOST_USER_PROTOCOL_F_BACKEND_SEND_FD = 10,
-    VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11,
-    VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD = 12,
-    VHOST_USER_PROTOCOL_F_RESET_DEVICE = 13,
-    VHOST_USER_PROTOCOL_F_INBAND_NOTIFICATIONS = 14,
-    VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS = 15,
-    VHOST_USER_PROTOCOL_F_MAX
-};
-
 /* Virtio transport features mapping */
 static const qmp_virtio_feature_map_t virtio_transport_map[] = {
     /* Virtio device transport features */
@@ -136,6 +118,9 @@ static const qmp_virtio_feature_map_t vhost_user_protocol_map[] = {
     FEATURE_ENTRY(VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS, \
             "VHOST_USER_PROTOCOL_F_CONFIGURE_MEM_SLOTS: Configuration for "
             "memory slots supported"),
+    FEATURE_ENTRY(VHOST_USER_PROTOCOL_F_STATUS, \
+            "VHOST_USER_PROTOCOL_F_STATUS: Querying and notifying back-end "
+            "device status supported"),
     { -1, "" }
 };
 
@@ -178,6 +163,8 @@ static const qmp_virtio_feature_map_t virtio_blk_feature_map[] = {
             "VIRTIO_BLK_F_DISCARD: Discard command supported"),
     FEATURE_ENTRY(VIRTIO_BLK_F_WRITE_ZEROES, \
             "VIRTIO_BLK_F_WRITE_ZEROES: Write zeroes command supported"),
+    FEATURE_ENTRY(VIRTIO_BLK_F_SECURE_ERASE, \
+            "VIRTIO_BLK_F_SECURE_ERASE: Secure erase supported"),
     FEATURE_ENTRY(VIRTIO_BLK_F_ZONED, \
             "VIRTIO_BLK_F_ZONED: Zoned block devices"),
 #ifndef VIRTIO_BLK_NO_LEGACY
@@ -301,6 +288,14 @@ static const qmp_virtio_feature_map_t virtio_net_feature_map[] = {
     FEATURE_ENTRY(VIRTIO_NET_F_CTRL_MAC_ADDR, \
             "VIRTIO_NET_F_CTRL_MAC_ADDR: MAC address set through control "
             "channel"),
+    FEATURE_ENTRY(VIRTIO_NET_F_NOTF_COAL, \
+            "VIRTIO_NET_F_NOTF_COAL: Device supports coalescing notifications"),
+    FEATURE_ENTRY(VIRTIO_NET_F_GUEST_USO4, \
+            "VIRTIO_NET_F_GUEST_USO4: Driver can receive USOv4"),
+    FEATURE_ENTRY(VIRTIO_NET_F_GUEST_USO6, \
+            "VIRTIO_NET_F_GUEST_USO4: Driver can receive USOv6"),
+    FEATURE_ENTRY(VIRTIO_NET_F_HOST_USO, \
+            "VIRTIO_NET_F_HOST_USO: Device can receive USO"),
     FEATURE_ENTRY(VIRTIO_NET_F_HASH_REPORT, \
             "VIRTIO_NET_F_HASH_REPORT: Hash reporting supported"),
     FEATURE_ENTRY(VIRTIO_NET_F_RSS, \
@@ -471,6 +466,18 @@ static const qmp_virtio_feature_map_t virtio_rng_feature_map[] = {
 };
 #endif
 
+/* virtio/vhost-gpio features mapping */
+#ifdef CONFIG_VHOST_USER_GPIO
+static const qmp_virtio_feature_map_t virtio_gpio_feature_map[] = {
+    FEATURE_ENTRY(VIRTIO_GPIO_F_IRQ, \
+            "VIRTIO_GPIO_F_IRQ: Device supports interrupts on GPIO lines"),
+    FEATURE_ENTRY(VHOST_USER_F_PROTOCOL_FEATURES, \
+            "VHOST_USER_F_PROTOCOL_FEATURES: Vhost-user protocol features "
+            "negotiation supported"),
+    { -1, "" }
+};
+#endif
+
 #define CONVERT_FEATURES(type, map, is_status, bitmap)   \
     ({                                                   \
         type *list = NULL;                               \
@@ -628,6 +635,12 @@ VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t bitmap)
             CONVERT_FEATURES(strList, virtio_rng_feature_map, 0, bitmap);
         break;
 #endif
+#ifdef CONFIG_VHOST_USER_GPIO
+    case VIRTIO_ID_GPIO:
+        features->dev_features =
+            CONVERT_FEATURES(strList, virtio_gpio_feature_map, 0, bitmap);
+        break;
+#endif
     /* No features */
     case VIRTIO_ID_9P:
     case VIRTIO_ID_PMEM:
@@ -653,7 +666,6 @@ VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t bitmap)
     case VIRTIO_ID_DMABUF:
     case VIRTIO_ID_PARAM_SERV:
     case VIRTIO_ID_AUDIO_POLICY:
-    case VIRTIO_ID_GPIO:
         break;
     default:
         g_assert_not_reached();
@@ -667,70 +679,43 @@ VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t bitmap)
     return features;
 }
 
+static int query_dev_child(Object *child, void *opaque)
+{
+    VirtioInfoList **vdevs = opaque;
+    Object *dev = object_dynamic_cast(child, TYPE_VIRTIO_DEVICE);
+    if (dev != NULL && DEVICE(dev)->realized) {
+        VirtIODevice *vdev = VIRTIO_DEVICE(dev);
+        VirtioInfo *info = g_new(VirtioInfo, 1);
+
+        /* Get canonical path & name of device */
+        info->path = object_get_canonical_path(dev);
+        info->name = g_strdup(vdev->name);
+        QAPI_LIST_PREPEND(*vdevs, info);
+    }
+    return 0;
+}
+
 VirtioInfoList *qmp_x_query_virtio(Error **errp)
 {
-    VirtioInfoList *list = NULL;
-    VirtioInfo *node;
-    VirtIODevice *vdev;
+    VirtioInfoList *vdevs = NULL;
 
-    QTAILQ_FOREACH(vdev, &virtio_list, next) {
-        DeviceState *dev = DEVICE(vdev);
-        Error *err = NULL;
-        QObject *obj = qmp_qom_get(dev->canonical_path, "realized", &err);
-
-        if (err == NULL) {
-            GString *is_realized = qobject_to_json_pretty(obj, true);
-            /* virtio device is NOT realized, remove it from list */
-            if (!strncmp(is_realized->str, "false", 4)) {
-                QTAILQ_REMOVE(&virtio_list, vdev, next);
-            } else {
-                node = g_new(VirtioInfo, 1);
-                node->path = g_strdup(dev->canonical_path);
-                node->name = g_strdup(vdev->name);
-                QAPI_LIST_PREPEND(list, node);
-            }
-           g_string_free(is_realized, true);
-        }
-        qobject_unref(obj);
+    /* Query the QOM composition tree recursively for virtio devices */
+    object_child_foreach_recursive(object_get_root(), query_dev_child, &vdevs);
+    if (vdevs == NULL) {
+        error_setg(errp, "No virtio devices found");
     }
-
-    return list;
+    return vdevs;
 }
 
 VirtIODevice *qmp_find_virtio_device(const char *path)
 {
-    VirtIODevice *vdev;
-
-    QTAILQ_FOREACH(vdev, &virtio_list, next) {
-        DeviceState *dev = DEVICE(vdev);
-
-        if (strcmp(dev->canonical_path, path) != 0) {
-            continue;
-        }
-
-        Error *err = NULL;
-        QObject *obj = qmp_qom_get(dev->canonical_path, "realized", &err);
-        if (err == NULL) {
-            GString *is_realized = qobject_to_json_pretty(obj, true);
-            /* virtio device is NOT realized, remove it from list */
-            if (!strncmp(is_realized->str, "false", 4)) {
-                g_string_free(is_realized, true);
-                qobject_unref(obj);
-                QTAILQ_REMOVE(&virtio_list, vdev, next);
-                return NULL;
-            }
-            g_string_free(is_realized, true);
-        } else {
-            /* virtio device doesn't exist in QOM tree */
-            QTAILQ_REMOVE(&virtio_list, vdev, next);
-            qobject_unref(obj);
-            return NULL;
-        }
-        /* device exists in QOM tree & is realized */
-        qobject_unref(obj);
-        return vdev;
+    /* Verify the canonical path is a realized virtio device */
+    Object *dev = object_dynamic_cast(object_resolve_path(path, NULL),
+                                      TYPE_VIRTIO_DEVICE);
+    if (!dev || !DEVICE(dev)->realized) {
+        return NULL;
     }
-    return NULL;
+    return VIRTIO_DEVICE(dev);
 }
 
 VirtioStatus *qmp_x_query_virtio_status(const char *path, Error **errp)
@@ -740,7 +725,7 @@ VirtioStatus *qmp_x_query_virtio_status(const char *path, Error **errp)
 
     vdev = qmp_find_virtio_device(path);
     if (vdev == NULL) {
-        error_setg(errp, "Path %s is not a VirtIODevice", path);
+        error_setg(errp, "Path %s is not a realized VirtIODevice", path);
         return NULL;
     }
 
diff --git a/hw/virtio/virtio-qmp.h b/hw/virtio/virtio-qmp.h
index 8af5f5e65a..245a446a56 100644
--- a/hw/virtio/virtio-qmp.h
+++ b/hw/virtio/virtio-qmp.h
@@ -15,13 +15,6 @@
 #include "hw/virtio/virtio.h"
 #include "hw/virtio/vhost.h"
 
-#include "qemu/queue.h"
-
-typedef QTAILQ_HEAD(QmpVirtIODeviceList, VirtIODevice) QmpVirtIODeviceList;
-
-/* QAPI list of realized VirtIODevices */
-extern QmpVirtIODeviceList virtio_list;
-
 VirtIODevice *qmp_find_virtio_device(const char *path);
 VirtioDeviceStatus *qmp_decode_status(uint8_t bitmap);
 VhostDeviceProtocols *qmp_decode_protocols(uint64_t bitmap);
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 4577f3f5b3..6facd64fbc 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -45,8 +45,6 @@
 #include "standard-headers/linux/virtio_mem.h"
 #include "standard-headers/linux/virtio_vsock.h"
 
-QmpVirtIODeviceList virtio_list;
-
 /*
  * Maximum size of virtio device config space
  */
@@ -999,7 +997,12 @@ void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
 /* Called within rcu_read_lock().  */
 static int virtqueue_num_heads(VirtQueue *vq, unsigned int idx)
 {
-    uint16_t num_heads = vring_avail_idx(vq) - idx;
+    uint16_t avail_idx, num_heads;
+
+    /* Use shadow index whenever possible. */
+    avail_idx = (vq->shadow_avail_idx != idx) ? vq->shadow_avail_idx
+                                              : vring_avail_idx(vq);
+    num_heads = avail_idx - idx;
 
     /* Check it isn't doing very strange things with descriptor numbers. */
     if (num_heads > vq->vring.num) {
@@ -1007,8 +1010,15 @@ static int virtqueue_num_heads(VirtQueue *vq, unsigned int idx)
                      idx, vq->shadow_avail_idx);
         return -EINVAL;
     }
-    /* On success, callers read a descriptor at vq->last_avail_idx.
-     * Make sure descriptor read does not bypass avail index read. */
+    /*
+     * On success, callers read a descriptor at vq->last_avail_idx.
+     * Make sure descriptor read does not bypass avail index read.
+     *
+     * This is necessary even if we are using a shadow index, since
+     * the shadow index could have been initialized by calling
+     * vring_avail_idx() outside of this function, i.e., by a guest
+     * memory read not accompanied by a barrier.
+     */
     if (num_heads) {
         smp_rmb();
     }
@@ -1039,9 +1049,10 @@ enum {
     VIRTQUEUE_READ_DESC_MORE = 1,   /* more buffers in chain */
 };
 
+/* Reads the 'desc->next' descriptor into '*desc'. */
 static int virtqueue_split_read_next_desc(VirtIODevice *vdev, VRingDesc *desc,
                                           MemoryRegionCache *desc_cache,
-                                          unsigned int max, unsigned int *next)
+                                          unsigned int max)
 {
     /* If this descriptor says it doesn't chain, we're done. */
     if (!(desc->flags & VRING_DESC_F_NEXT)) {
@@ -1049,16 +1060,12 @@ static int virtqueue_split_read_next_desc(VirtIODevice *vdev, VRingDesc *desc,
     }
 
     /* Check they're not leading us off end of descriptors. */
-    *next = desc->next;
-    /* Make sure compiler knows to grab that: we don't want it changing! */
-    smp_wmb();
-
-    if (*next >= max) {
-        virtio_error(vdev, "Desc next is %u", *next);
+    if (desc->next >= max) {
+        virtio_error(vdev, "Desc next is %u", desc->next);
         return VIRTQUEUE_READ_DESC_ERROR;
     }
 
-    vring_split_desc_read(vdev, desc, desc_cache, *next);
+    vring_split_desc_read(vdev, desc, desc_cache, desc->next);
     return VIRTQUEUE_READ_DESC_MORE;
 }
 
@@ -1071,10 +1078,12 @@ static void virtqueue_split_get_avail_bytes(VirtQueue *vq,
     VirtIODevice *vdev = vq->vdev;
     unsigned int idx;
     unsigned int total_bufs, in_total, out_total;
-    MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
+    MemoryRegionCache indirect_desc_cache;
     int64_t len = 0;
     int rc;
 
+    address_space_cache_init_empty(&indirect_desc_cache);
+
     idx = vq->last_avail_idx;
     total_bufs = in_total = out_total = 0;
 
@@ -1136,7 +1145,7 @@ static void virtqueue_split_get_avail_bytes(VirtQueue *vq,
                 goto done;
             }
 
-            rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i);
+            rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max);
         } while (rc == VIRTQUEUE_READ_DESC_MORE);
 
         if (rc == VIRTQUEUE_READ_DESC_ERROR) {
@@ -1207,12 +1216,14 @@ static void virtqueue_packed_get_avail_bytes(VirtQueue *vq,
     VirtIODevice *vdev = vq->vdev;
     unsigned int idx;
     unsigned int total_bufs, in_total, out_total;
+    MemoryRegionCache indirect_desc_cache;
     MemoryRegionCache *desc_cache;
-    MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
     int64_t len = 0;
     VRingPackedDesc desc;
     bool wrap_counter;
 
+    address_space_cache_init_empty(&indirect_desc_cache);
+
     idx = vq->last_avail_idx;
     wrap_counter = vq->last_avail_wrap_counter;
     total_bufs = in_total = out_total = 0;
@@ -1487,7 +1498,7 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t sz)
 {
     unsigned int i, head, max;
     VRingMemoryRegionCaches *caches;
-    MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
+    MemoryRegionCache indirect_desc_cache;
     MemoryRegionCache *desc_cache;
     int64_t len;
     VirtIODevice *vdev = vq->vdev;
@@ -1498,6 +1509,8 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t sz)
     VRingDesc desc;
     int rc;
 
+    address_space_cache_init_empty(&indirect_desc_cache);
+
     RCU_READ_LOCK_GUARD();
     if (virtio_queue_empty_rcu(vq)) {
         goto done;
@@ -1587,7 +1600,7 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t sz)
             goto err_undo_map;
         }
 
-        rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max, &i);
+        rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max);
     } while (rc == VIRTQUEUE_READ_DESC_MORE);
 
     if (rc == VIRTQUEUE_READ_DESC_ERROR) {
@@ -1624,7 +1637,7 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz)
 {
     unsigned int i, max;
     VRingMemoryRegionCaches *caches;
-    MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
+    MemoryRegionCache indirect_desc_cache;
     MemoryRegionCache *desc_cache;
     int64_t len;
     VirtIODevice *vdev = vq->vdev;
@@ -1636,6 +1649,8 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t sz)
     uint16_t id;
     int rc;
 
+    address_space_cache_init_empty(&indirect_desc_cache);
+
     RCU_READ_LOCK_GUARD();
     if (virtio_queue_packed_empty_rcu(vq)) {
         goto done;
@@ -3651,7 +3666,6 @@ static void virtio_device_realize(DeviceState *dev, Error **errp)
     vdev->listener.commit = virtio_memory_listener_commit;
     vdev->listener.name = "virtio";
     memory_listener_register(&vdev->listener, vdev->dma_as);
-    QTAILQ_INSERT_TAIL(&virtio_list, vdev, next);
 }
 
 static void virtio_device_unrealize(DeviceState *dev)
@@ -3666,7 +3680,6 @@ static void virtio_device_unrealize(DeviceState *dev)
         vdc->unrealize(dev);
     }
 
-    QTAILQ_REMOVE(&virtio_list, vdev, next);
     g_free(vdev->bus_name);
     vdev->bus_name = NULL;
 }
@@ -3840,8 +3853,6 @@ static void virtio_device_class_init(ObjectClass *klass, void *data)
     vdc->stop_ioeventfd = virtio_device_stop_ioeventfd_impl;
 
     vdc->legacy_features |= VIRTIO_LEGACY_FEATURES;
-
-    QTAILQ_INIT(&virtio_list);
 }
 
 bool virtio_device_ioeventfd_enabled(VirtIODevice *vdev)
@@ -3970,13 +3981,15 @@ VirtioQueueElement *qmp_x_query_virtio_queue_element(const char *path,
     } else {
         unsigned int head, i, max;
         VRingMemoryRegionCaches *caches;
-        MemoryRegionCache indirect_desc_cache = MEMORY_REGION_CACHE_INVALID;
+        MemoryRegionCache indirect_desc_cache;
         MemoryRegionCache *desc_cache;
         VRingDesc desc;
         VirtioRingDescList *list = NULL;
         VirtioRingDescList *node;
         int rc; int ndescs;
 
+        address_space_cache_init_empty(&indirect_desc_cache);
+
         RCU_READ_LOCK_GUARD();
 
         max = vq->vring.num;
@@ -4041,8 +4054,7 @@ VirtioQueueElement *qmp_x_query_virtio_queue_element(const char *path,
             list = node;
 
             ndescs++;
-            rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache,
-                                                max, &i);
+            rc = virtqueue_split_read_next_desc(vdev, &desc, desc_cache, max);
         } while (rc == VIRTQUEUE_READ_DESC_MORE);
         element->descs = list;
 done: