On 7/21/25 9:23 AM, Akihiko Odaki wrote:
> On 2025/07/18 17:52, Paolo Abeni wrote:
>> Extend the VirtioDeviceFeatures struct with an additional u64
>> to track unknown features in the 64-127 bit range and decode
>> the full virtio features spaces for vhost and virtio devices.
>>
>> Also add entries for the soon-to-be-supported virtio net GSO over
>> UDP features.
>>
>> Signed-off-by: Paolo Abeni <pab...@redhat.com>
>> ---
>> v2 -> v3:
>> - unknown-dev-features-dword2 -> unknown-dev-features2
>> - _array -> _ex
>> - fixed typos in entries description
>>
>> v1 -> v2:
>> - uint128_t -> uint64_t[]
>> ---
>> hw/virtio/virtio-hmp-cmds.c | 3 +-
>> hw/virtio/virtio-qmp.c | 89 ++++++++++++++++++++++++++-----------
>> hw/virtio/virtio-qmp.h | 3 +-
>> qapi/virtio.json | 8 +++-
>> 4 files changed, 73 insertions(+), 30 deletions(-)
>>
>> diff --git a/hw/virtio/virtio-hmp-cmds.c b/hw/virtio/virtio-hmp-cmds.c
>> index 7d8677bcf0..1daae482d3 100644
>> --- a/hw/virtio/virtio-hmp-cmds.c
>> +++ b/hw/virtio/virtio-hmp-cmds.c
>> @@ -74,7 +74,8 @@ static void hmp_virtio_dump_features(Monitor *mon,
>> }
>>
>> if (features->has_unknown_dev_features) {
>> - monitor_printf(mon, " unknown-features(0x%016"PRIx64")\n",
>> + monitor_printf(mon, "
>> unknown-features(0x%016"PRIx64"%016"PRIx64")\n",
>> + features->unknown_dev_features2,
>> features->unknown_dev_features);
>> }
>> }
>> diff --git a/hw/virtio/virtio-qmp.c b/hw/virtio/virtio-qmp.c
>> index 3b6377cf0d..03c6163cf4 100644
>> --- a/hw/virtio/virtio-qmp.c
>> +++ b/hw/virtio/virtio-qmp.c
>> @@ -325,6 +325,20 @@ static const qmp_virtio_feature_map_t
>> virtio_net_feature_map[] = {
>> FEATURE_ENTRY(VHOST_USER_F_PROTOCOL_FEATURES, \
>> "VHOST_USER_F_PROTOCOL_FEATURES: Vhost-user protocol features "
>> "negotiation supported"),
>> + FEATURE_ENTRY(VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO, \
>> + "VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO: Driver can receive GSO over
>> "
>> + "UDP tunnel packets"),
>> + FEATURE_ENTRY(VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO_CSUM, \
>> + "VIRTIO_NET_F_GUEST_UDP_TUNNEL_GSO: Driver can receive GSO over
>> "
>> + "UDP tunnel packets requiring checksum offload for the outer "
>> + "header"),
>> + FEATURE_ENTRY(VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO, \
>> + "VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO: Device can receive GSO over "
>> + "UDP tunnel packets"),
>> + FEATURE_ENTRY(VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO_CSUM, \
>> + "VIRTIO_NET_F_HOST_UDP_TUNNEL_GSO: Device can receive GSO over "
>> + "UDP tunnel packets requiring checksum offload for the outer "
>> + "header"),
>> { -1, "" }
>> };
>> #endif
>> @@ -510,6 +524,24 @@ static const qmp_virtio_feature_map_t
>> virtio_gpio_feature_map[] = {
>> list; \
>> })
>>
>> +#define CONVERT_FEATURES_EX(type, map, bitmap) \
>> + ({ \
>> + type *list = NULL; \
>> + type *node; \
>> + for (i = 0; map[i].virtio_bit != -1; i++) { \
>> + bit = map[i].virtio_bit; \
>> + if (!virtio_has_feature_ex(bitmap, bit)) { \
>> + continue; \
>> + } \
>> + node = g_new0(type, 1); \
>> + node->value = g_strdup(map[i].feature_desc); \
>> + node->next = list; \
>> + list = node; \
>> + virtio_clear_feature_ex(bitmap, bit); \
>> + } \
>> + list; \
>> + })
>> +
>> VirtioDeviceStatus *qmp_decode_status(uint8_t bitmap)
>> {
>> VirtioDeviceStatus *status;
>> @@ -545,109 +577,112 @@ VhostDeviceProtocols *qmp_decode_protocols(uint64_t
>> bitmap)
>> return vhu_protocols;
>> }
>>
>> -VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t
>> bitmap)
>> +VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id,
>> + const uint64_t *bmap)
>> {
>> + uint64_t bitmap[VIRTIO_FEATURES_DWORDS];
>> VirtioDeviceFeatures *features;
>> uint64_t bit;
>> int i;
>>
>> + virtio_features_copy(bitmap, bmap);
>> features = g_new0(VirtioDeviceFeatures, 1);
>> features->has_dev_features = true;
>>
>> /* transport features */
>> - features->transports = CONVERT_FEATURES(strList, virtio_transport_map,
>> 0,
>> - bitmap);
>> + features->transports = CONVERT_FEATURES_EX(strList,
>> virtio_transport_map,
>> + bitmap);
>>
>> /* device features */
>> switch (device_id) {
>> #ifdef CONFIG_VIRTIO_SERIAL
>> case VIRTIO_ID_CONSOLE:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_serial_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_serial_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_BLK
>> case VIRTIO_ID_BLOCK:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_blk_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_blk_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_GPU
>> case VIRTIO_ID_GPU:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_gpu_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_gpu_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_NET
>> case VIRTIO_ID_NET:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_net_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_net_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_SCSI
>> case VIRTIO_ID_SCSI:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_scsi_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_scsi_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_BALLOON
>> case VIRTIO_ID_BALLOON:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_balloon_feature_map, 0,
>> bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_balloon_feature_map,
>> bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_IOMMU
>> case VIRTIO_ID_IOMMU:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_iommu_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_iommu_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_INPUT
>> case VIRTIO_ID_INPUT:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_input_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_input_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VHOST_USER_FS
>> case VIRTIO_ID_FS:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_fs_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_fs_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VHOST_VSOCK
>> case VIRTIO_ID_VSOCK:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_vsock_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_vsock_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_CRYPTO
>> case VIRTIO_ID_CRYPTO:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_crypto_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_crypto_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_MEM
>> case VIRTIO_ID_MEM:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_mem_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_mem_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_I2C_ADAPTER
>> case VIRTIO_ID_I2C_ADAPTER:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_i2c_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_i2c_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VIRTIO_RNG
>> case VIRTIO_ID_RNG:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_rng_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_rng_feature_map, bitmap);
>> break;
>> #endif
>> #ifdef CONFIG_VHOST_USER_GPIO
>> case VIRTIO_ID_GPIO:
>> features->dev_features =
>> - CONVERT_FEATURES(strList, virtio_gpio_feature_map, 0, bitmap);
>> + CONVERT_FEATURES_EX(strList, virtio_gpio_feature_map, bitmap);
>> break;
>> #endif
>> /* No features */
>> @@ -680,9 +715,10 @@ VirtioDeviceFeatures *qmp_decode_features(uint16_t
>> device_id, uint64_t bitmap)
>> g_assert_not_reached();
>> }
>>
>> - features->has_unknown_dev_features = bitmap != 0;
>> + features->has_unknown_dev_features = !virtio_features_empty(bitmap);
>> if (features->has_unknown_dev_features) {
>> - features->unknown_dev_features = bitmap;
>> + features->unknown_dev_features = bitmap[0];
>> + features->unknown_dev_features2 = bitmap[1];
>> }
>>
>> return features;
>> @@ -743,11 +779,11 @@ VirtioStatus *qmp_x_query_virtio_status(const char
>> *path, Error **errp)
>> status->device_id = vdev->device_id;
>> status->vhost_started = vdev->vhost_started;
>> status->guest_features = qmp_decode_features(vdev->device_id,
>> - vdev->guest_features);
>> + vdev->guest_features_ex);
>> status->host_features = qmp_decode_features(vdev->device_id,
>> - vdev->host_features);
>> + vdev->host_features_ex);
>> status->backend_features = qmp_decode_features(vdev->device_id,
>> - vdev->backend_features);
>> + vdev->backend_features_ex);
>>
>> switch (vdev->device_endian) {
>> case VIRTIO_DEVICE_ENDIAN_LITTLE:
>> @@ -785,11 +821,12 @@ VirtioStatus *qmp_x_query_virtio_status(const char
>> *path, Error **errp)
>> status->vhost_dev->nvqs = hdev->nvqs;
>> status->vhost_dev->vq_index = hdev->vq_index;
>> status->vhost_dev->features =
>> - qmp_decode_features(vdev->device_id, hdev->features);
>> + qmp_decode_features(vdev->device_id, hdev->features_ex);
>> status->vhost_dev->acked_features =
>> - qmp_decode_features(vdev->device_id, hdev->acked_features);
>> + qmp_decode_features(vdev->device_id, hdev->acked_features_ex);
>> status->vhost_dev->backend_features =
>> - qmp_decode_features(vdev->device_id, hdev->backend_features);
>> + qmp_decode_features(vdev->device_id, hdev->backend_features_ex);
>> +
>> status->vhost_dev->protocol_features =
>> qmp_decode_protocols(hdev->protocol_features);
>> status->vhost_dev->max_queues = hdev->max_queues;
>> diff --git a/hw/virtio/virtio-qmp.h b/hw/virtio/virtio-qmp.h
>> index 245a446a56..e0a1e49035 100644
>> --- a/hw/virtio/virtio-qmp.h
>> +++ b/hw/virtio/virtio-qmp.h
>> @@ -18,6 +18,7 @@
>> VirtIODevice *qmp_find_virtio_device(const char *path);
>> VirtioDeviceStatus *qmp_decode_status(uint8_t bitmap);
>> VhostDeviceProtocols *qmp_decode_protocols(uint64_t bitmap);
>> -VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id, uint64_t
>> bitmap);
>> +VirtioDeviceFeatures *qmp_decode_features(uint16_t device_id,
>> + const uint64_t *bitmap);
>>
>> #endif
>> diff --git a/qapi/virtio.json b/qapi/virtio.json
>> index 9d652fe4a8..f2e2dd6e97 100644
>> --- a/qapi/virtio.json
>> +++ b/qapi/virtio.json
>> @@ -490,14 +490,18 @@
>> # unique features)
>> #
>> # @unknown-dev-features: Virtio device features bitmap that have not
>> -# been decoded
>> +# been decoded (bits 0-63)
>> +#
>> +# @unknown-dev-features2: Virtio device features bitmap that have not
>> +# been decoded (bits 64-127)
>
> This documentation should contain "(since 10.1)" as described in:
> docs/devel/qapi-code-gen.rst
Just to be pedant, since there is a little ambiguity between the
examples in docs/devel/qapi-code-gen.rst and the actual code e.g. in
qapi/qom.json, I'll use:
# @unknown-dev-features2: Virtio device features bitmap that have not
# been decoded (bits 64-127) (since 10.2)
/P
