diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c
index 30492ec..60f9ff9 100644
--- a/hw/9pfs/virtio-9p-device.c
+++ b/hw/9pfs/virtio-9p-device.c
@@ -21,7 +21,7 @@
 #include "virtio-9p-coth.h"
 #include "hw/virtio/virtio-access.h"
 
-static uint32_t virtio_9p_get_features(VirtIODevice *vdev, uint32_t features)
+static uint64_t virtio_9p_get_features(VirtIODevice *vdev, uint64_t features)
 {
     virtio_add_feature(&features, VIRTIO_9P_MOUNT_TAG);
     return features;
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index e6afe97..cd539aa 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -718,7 +718,7 @@ static void virtio_blk_set_config(VirtIODevice *vdev, const uint8_t *config)
     aio_context_release(blk_get_aio_context(s->blk));
 }
 
-static uint32_t virtio_blk_get_features(VirtIODevice *vdev, uint32_t features)
+static uint64_t virtio_blk_get_features(VirtIODevice *vdev, uint64_t features)
 {
     VirtIOBlock *s = VIRTIO_BLK(vdev);
 
diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
index 6e2ad82..95be9fc 100644
--- a/hw/char/virtio-serial-bus.c
+++ b/hw/char/virtio-serial-bus.c
@@ -498,7 +498,7 @@ static void handle_input(VirtIODevice *vdev, VirtQueue *vq)
     }
 }
 
-static uint32_t get_features(VirtIODevice *vdev, uint32_t features)
+static uint64_t get_features(VirtIODevice *vdev, uint64_t features)
 {
     VirtIOSerial *vser;
 
diff --git a/hw/input/virtio-input.c b/hw/input/virtio-input.c
index e615c5c..c4f4b3c 100644
--- a/hw/input/virtio-input.c
+++ b/hw/input/virtio-input.c
@@ -166,7 +166,7 @@ static void virtio_input_set_config(VirtIODevice *vdev,
     virtio_notify_config(vdev);
 }
 
-static uint32_t virtio_input_get_features(VirtIODevice *vdev, uint32_t f)
+static uint64_t virtio_input_get_features(VirtIODevice *vdev, uint64_t f)
 {
     return f;
 }
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 3af6faf..b21ef6b 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -435,7 +435,7 @@ static void virtio_net_set_queues(VirtIONet *n)
 
 static void virtio_net_set_multiqueue(VirtIONet *n, int multiqueue);
 
-static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
+static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features)
 {
     VirtIONet *n = VIRTIO_NET(vdev);
     NetClientState *nc = qemu_get_queue(n->nic);
@@ -468,9 +468,9 @@ static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features)
     return vhost_net_get_features(get_vhost_net(nc->peer), features);
 }
 
-static uint32_t virtio_net_bad_features(VirtIODevice *vdev)
+static uint64_t virtio_net_bad_features(VirtIODevice *vdev)
 {
-    uint32_t features = 0;
+    uint64_t features = 0;
 
     /* Linux kernel 2.6.25.  It understood MAC (as everyone must),
      * but also these: */
@@ -1032,10 +1032,12 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t
             if (i == 0)
                 return -1;
             error_report("virtio-net unexpected empty queue: "
-                    "i %zd mergeable %d offset %zd, size %zd, "
-                    "guest hdr len %zd, host hdr len %zd guest features 0x%x",
-                    i, n->mergeable_rx_bufs, offset, size,
-                    n->guest_hdr_len, n->host_hdr_len, vdev->guest_features);
+                         "i %zd mergeable %d offset %zd, size %zd, "
+                         "guest hdr len %zd, host hdr len %zd "
+                         "guest features 0x%" PRIx64,
+                         i, n->mergeable_rx_bufs, offset, size,
+                         n->guest_hdr_len, n->host_hdr_len,
+                         vdev->guest_features);
             exit(1);
         }
 
@@ -1549,7 +1551,7 @@ static void virtio_net_guest_notifier_mask(VirtIODevice *vdev, int idx,
                              vdev, idx, mask);
 }
 
-static void virtio_net_set_config_size(VirtIONet *n, uint32_t host_features)
+static void virtio_net_set_config_size(VirtIONet *n, uint64_t host_features)
 {
     int i, config_size = 0;
     virtio_add_feature(&host_features, VIRTIO_NET_F_MAC);
diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
index 335f442..9c76486 100644
--- a/hw/scsi/vhost-scsi.c
+++ b/hw/scsi/vhost-scsi.c
@@ -151,8 +151,8 @@ static void vhost_scsi_stop(VHostSCSI *s)
     vhost_dev_disable_notifiers(&s->dev, vdev);
 }
 
-static uint32_t vhost_scsi_get_features(VirtIODevice *vdev,
-                                        uint32_t features)
+static uint64_t vhost_scsi_get_features(VirtIODevice *vdev,
+                                        uint64_t features)
 {
     VHostSCSI *s = VHOST_SCSI(vdev);
 
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
index e242fef..36ae66e 100644
--- a/hw/scsi/virtio-scsi.c
+++ b/hw/scsi/virtio-scsi.c
@@ -628,8 +628,8 @@ static void virtio_scsi_set_config(VirtIODevice *vdev,
     vs->cdb_size = virtio_ldl_p(vdev, &scsiconf->cdb_size);
 }
 
-static uint32_t virtio_scsi_get_features(VirtIODevice *vdev,
-                                         uint32_t requested_features)
+static uint64_t virtio_scsi_get_features(VirtIODevice *vdev,
+                                         uint64_t requested_features)
 {
     VirtIOSCSI *s = VIRTIO_SCSI(vdev);
 
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index 484c3c3..734f35b 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -310,7 +310,7 @@ static void virtio_balloon_set_config(VirtIODevice *vdev,
     trace_virtio_balloon_set_config(dev->actual, oldactual);
 }
 
-static uint32_t virtio_balloon_get_features(VirtIODevice *vdev, uint32_t f)
+static uint64_t virtio_balloon_get_features(VirtIODevice *vdev, uint64_t f)
 {
     f |= (1 << VIRTIO_BALLOON_F_STATS_VQ);
     return f;
diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c
index 06e7178..420c39f 100644
--- a/hw/virtio/virtio-rng.c
+++ b/hw/virtio/virtio-rng.c
@@ -99,7 +99,7 @@ static void handle_input(VirtIODevice *vdev, VirtQueue *vq)
     virtio_rng_process(vrng);
 }
 
-static uint32_t get_features(VirtIODevice *vdev, uint32_t f)
+static uint64_t get_features(VirtIODevice *vdev, uint64_t f)
 {
     return f;
 }
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 96d9c6a..5b9b480 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -893,6 +893,13 @@ static bool virtio_device_endian_needed(void *opaque)
     return vdev->device_endian != virtio_default_endian();
 }
 
+static bool virtio_64bit_features_needed(void *opaque)
+{
+    VirtIODevice *vdev = opaque;
+
+    return (vdev->host_features >> 32) != 0;
+}
+
 static const VMStateDescription vmstate_virtio_device_endian = {
     .name = "virtio/device_endian",
     .version_id = 1,
@@ -903,6 +910,16 @@ static const VMStateDescription vmstate_virtio_device_endian = {
     }
 };
 
+static const VMStateDescription vmstate_virtio_64bit_features = {
+    .name = "virtio/64bit_features",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(guest_features, VirtIODevice),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 static const VMStateDescription vmstate_virtio = {
     .name = "virtio",
     .version_id = 1,
@@ -916,6 +933,10 @@ static const VMStateDescription vmstate_virtio = {
             .vmsd = &vmstate_virtio_device_endian,
             .needed = &virtio_device_endian_needed
         },
+        {
+            .vmsd = &vmstate_virtio_64bit_features,
+            .needed = &virtio_64bit_features_needed
+        },
         { 0 }
     }
 };
@@ -925,6 +946,7 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f)
     BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
     VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
     VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev);
+    uint32_t guest_features_lo = (vdev->guest_features & 0xffffffff);
     int i;
 
     if (k->save_config) {
@@ -934,7 +956,7 @@ void virtio_save(VirtIODevice *vdev, QEMUFile *f)
     qemu_put_8s(f, &vdev->status);
     qemu_put_8s(f, &vdev->isr);
     qemu_put_be16s(f, &vdev->queue_sel);
-    qemu_put_be32s(f, &vdev->guest_features);
+    qemu_put_be32s(f, &guest_features_lo);
     qemu_put_be32(f, vdev->config_len);
     qemu_put_buffer(f, vdev->config, vdev->config_len);
 
@@ -1011,11 +1033,6 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
     }
     qemu_get_be32s(f, &features);
 
-    if (virtio_set_features(vdev, features) < 0) {
-        error_report("Features 0x%x unsupported. Allowed features: 0x%x",
-                     features, vdev->host_features);
-        return -1;
-    }
     config_len = qemu_get_be32(f);
 
     /*
@@ -1081,6 +1098,28 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f, int version_id)
         vdev->device_endian = virtio_default_endian();
     }
 
+    if (virtio_64bit_features_needed(vdev)) {
+        /*
+         * Subsection load filled vdev->guest_features.  Run them
+         * through virtio_set_features to sanity-check them against
+         * host_features.
+         */
+        uint64_t features64 = vdev->guest_features;
+        if (virtio_set_features(vdev, features64) < 0) {
+            error_report("Features 0x%" PRIx64 " unsupported. "
+                         "Allowed features: 0x%" PRIx64,
+                         features64, vdev->host_features);
+            return -1;
+        }
+    } else {
+        if (virtio_set_features(vdev, features) < 0) {
+            error_report("Features 0x%x unsupported. "
+                         "Allowed features: 0x%" PRIx64,
+                         features, vdev->host_features);
+            return -1;
+        }
+    }
+
     for (i = 0; i < num; i++) {
         if (vdev->vq[i].pa) {
             uint16_t nheads;
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index f1f9ca5..9e26c32 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -73,8 +73,8 @@ struct VirtIODevice
     uint8_t status;
     uint8_t isr;
     uint16_t queue_sel;
-    uint32_t guest_features;
-    uint32_t host_features;
+    uint64_t guest_features;
+    uint64_t host_features;
     size_t config_len;
     void *config;
     uint16_t config_vector;
@@ -96,8 +96,8 @@ typedef struct VirtioDeviceClass {
     /* This is what a VirtioDevice must implement */
     DeviceRealize realize;
     DeviceUnrealize unrealize;
-    uint32_t (*get_features)(VirtIODevice *vdev, uint32_t requested_features);
-    uint32_t (*bad_features)(VirtIODevice *vdev);
+    uint64_t (*get_features)(VirtIODevice *vdev, uint64_t requested_features);
+    uint64_t (*bad_features)(VirtIODevice *vdev);
     void (*set_features)(VirtIODevice *vdev, uint32_t val);
     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
@@ -194,10 +194,10 @@ typedef struct VirtIOSCSIConf VirtIOSCSIConf;
 typedef struct VirtIORNGConf VirtIORNGConf;
 
 #define DEFINE_VIRTIO_COMMON_FEATURES(_state, _field) \
-	DEFINE_PROP_BIT("indirect_desc", _state, _field, \
-			VIRTIO_RING_F_INDIRECT_DESC, true), \
-	DEFINE_PROP_BIT("event_idx", _state, _field, \
-			VIRTIO_RING_F_EVENT_IDX, true)
+	DEFINE_PROP_BIT64("indirect_desc", _state, _field, \
+			  VIRTIO_RING_F_INDIRECT_DESC, true), \
+	DEFINE_PROP_BIT64("event_idx", _state, _field, \
+			  VIRTIO_RING_F_EVENT_IDX, true)
 
 hwaddr virtio_queue_get_desc_addr(VirtIODevice *vdev, int n);
 hwaddr virtio_queue_get_avail_addr(VirtIODevice *vdev, int n);
@@ -224,21 +224,21 @@ void virtio_irq(VirtQueue *vq);
 VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
 VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
 
-static inline void virtio_add_feature(uint32_t *features, unsigned int fbit)
+static inline void virtio_add_feature(uint64_t *features, unsigned int fbit)
 {
-    assert(fbit < 32);
+    assert(fbit < 64);
     *features |= (1 << fbit);
 }
 
-static inline void virtio_clear_feature(uint32_t *features, unsigned int fbit)
+static inline void virtio_clear_feature(uint64_t *features, unsigned int fbit)
 {
-    assert(fbit < 32);
+    assert(fbit < 64);
     *features &= ~(1 << fbit);
 }
 
-static inline bool __virtio_has_feature(uint32_t features, unsigned int fbit)
+static inline bool __virtio_has_feature(uint64_t features, unsigned int fbit)
 {
-    assert(fbit < 32);
+    assert(fbit < 64);
     return !!(features & (1 << fbit));
 }
 
