On Mon, 4 Oct 2021 21:38:04 +0200 Christian Schoenebeck <qemu_...@crudebyte.com> wrote:
> Refactor VIRTQUEUE_MAX_SIZE to effectively become a runtime > variable per virtio user. > > Reasons: > > (1) VIRTQUEUE_MAX_SIZE should reflect the absolute theoretical > maximum queue size possible. Which is actually the maximum > queue size allowed by the virtio protocol. The appropriate > value for VIRTQUEUE_MAX_SIZE would therefore be 32768: > > > https://docs.oasis-open.org/virtio/virtio/v1.1/cs01/virtio-v1.1-cs01.html#x1-240006 > > Apparently VIRTQUEUE_MAX_SIZE was instead defined with a > more or less arbitrary value of 1024 in the past, which > limits the maximum transfer size with virtio to 4M > (more precise: 1024 * PAGE_SIZE, with the latter typically > being 4k). > > (2) Additionally the current value of 1024 poses a hidden limit, > invisible to guest, which causes a system hang with the > following QEMU error if guest tries to exceed it: > > virtio: too many write descriptors in indirect table > > (3) Unfortunately not all virtio users in QEMU would currently > work correctly with the new value of 32768. > > So let's turn this hard coded global value into a runtime > variable as a first step in this commit, configurable for each > virtio user by passing a corresponding value with virtio_init() > call. > > Signed-off-by: Christian Schoenebeck <qemu_...@crudebyte.com> > --- Reviewed-by: Greg Kurz <gr...@kaod.org> > hw/9pfs/virtio-9p-device.c | 3 ++- > hw/block/vhost-user-blk.c | 2 +- > hw/block/virtio-blk.c | 3 ++- > hw/char/virtio-serial-bus.c | 2 +- > hw/display/virtio-gpu-base.c | 2 +- > hw/input/virtio-input.c | 2 +- > hw/net/virtio-net.c | 15 ++++++++------- > hw/scsi/virtio-scsi.c | 2 +- > hw/virtio/vhost-user-fs.c | 2 +- > hw/virtio/vhost-user-i2c.c | 3 ++- > hw/virtio/vhost-vsock-common.c | 2 +- > hw/virtio/virtio-balloon.c | 4 ++-- > hw/virtio/virtio-crypto.c | 3 ++- > hw/virtio/virtio-iommu.c | 2 +- > hw/virtio/virtio-mem.c | 2 +- > hw/virtio/virtio-pmem.c | 2 +- > hw/virtio/virtio-rng.c | 2 +- > hw/virtio/virtio.c | 35 +++++++++++++++++++++++----------- > include/hw/virtio/virtio.h | 5 ++++- > 19 files changed, 57 insertions(+), 36 deletions(-) > > diff --git a/hw/9pfs/virtio-9p-device.c b/hw/9pfs/virtio-9p-device.c > index 54ee93b71f..cd5d95dd51 100644 > --- a/hw/9pfs/virtio-9p-device.c > +++ b/hw/9pfs/virtio-9p-device.c > @@ -216,7 +216,8 @@ static void virtio_9p_device_realize(DeviceState *dev, > Error **errp) > } > > v->config_size = sizeof(struct virtio_9p_config) + strlen(s->fsconf.tag); > - virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size); > + virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, v->config_size, > + VIRTQUEUE_MAX_SIZE); > v->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output); > } > > diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c > index ba13cb87e5..336f56705c 100644 > --- a/hw/block/vhost-user-blk.c > +++ b/hw/block/vhost-user-blk.c > @@ -491,7 +491,7 @@ static void vhost_user_blk_device_realize(DeviceState > *dev, Error **errp) > } > > virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, > - sizeof(struct virtio_blk_config)); > + sizeof(struct virtio_blk_config), VIRTQUEUE_MAX_SIZE); > > s->virtqs = g_new(VirtQueue *, s->num_queues); > for (i = 0; i < s->num_queues; i++) { > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c > index f139cd7cc9..9c0f46815c 100644 > --- a/hw/block/virtio-blk.c > +++ b/hw/block/virtio-blk.c > @@ -1213,7 +1213,8 @@ static void virtio_blk_device_realize(DeviceState *dev, > Error **errp) > > virtio_blk_set_config_size(s, s->host_features); > > - virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size); > + virtio_init(vdev, "virtio-blk", VIRTIO_ID_BLOCK, s->config_size, > + VIRTQUEUE_MAX_SIZE); > > s->blk = conf->conf.blk; > s->rq = NULL; > diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c > index f01ec2137c..9ad9111115 100644 > --- a/hw/char/virtio-serial-bus.c > +++ b/hw/char/virtio-serial-bus.c > @@ -1045,7 +1045,7 @@ static void virtio_serial_device_realize(DeviceState > *dev, Error **errp) > config_size = offsetof(struct virtio_console_config, emerg_wr); > } > virtio_init(vdev, "virtio-serial", VIRTIO_ID_CONSOLE, > - config_size); > + config_size, VIRTQUEUE_MAX_SIZE); > > /* Spawn a new virtio-serial bus on which the ports will ride as devices > */ > qbus_init(&vser->bus, sizeof(vser->bus), TYPE_VIRTIO_SERIAL_BUS, > diff --git a/hw/display/virtio-gpu-base.c b/hw/display/virtio-gpu-base.c > index c8da4806e0..20b06a7adf 100644 > --- a/hw/display/virtio-gpu-base.c > +++ b/hw/display/virtio-gpu-base.c > @@ -171,7 +171,7 @@ virtio_gpu_base_device_realize(DeviceState *qdev, > > g->virtio_config.num_scanouts = cpu_to_le32(g->conf.max_outputs); > virtio_init(VIRTIO_DEVICE(g), "virtio-gpu", VIRTIO_ID_GPU, > - sizeof(struct virtio_gpu_config)); > + sizeof(struct virtio_gpu_config), VIRTQUEUE_MAX_SIZE); > > if (virtio_gpu_virgl_enabled(g->conf)) { > /* use larger control queue in 3d mode */ > diff --git a/hw/input/virtio-input.c b/hw/input/virtio-input.c > index 54bcb46c74..345eb2cce7 100644 > --- a/hw/input/virtio-input.c > +++ b/hw/input/virtio-input.c > @@ -258,7 +258,7 @@ static void virtio_input_device_realize(DeviceState *dev, > Error **errp) > assert(vinput->cfg_size <= sizeof(virtio_input_config)); > > virtio_init(vdev, "virtio-input", VIRTIO_ID_INPUT, > - vinput->cfg_size); > + vinput->cfg_size, VIRTQUEUE_MAX_SIZE); > vinput->evt = virtio_add_queue(vdev, 64, virtio_input_handle_evt); > vinput->sts = virtio_add_queue(vdev, 64, virtio_input_handle_sts); > } > diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c > index f205331dcf..f74b5f6268 100644 > --- a/hw/net/virtio-net.c > +++ b/hw/net/virtio-net.c > @@ -1746,9 +1746,9 @@ static ssize_t virtio_net_receive_rcu(NetClientState > *nc, const uint8_t *buf, > VirtIONet *n = qemu_get_nic_opaque(nc); > VirtIONetQueue *q = virtio_net_get_subqueue(nc); > VirtIODevice *vdev = VIRTIO_DEVICE(n); > - VirtQueueElement *elems[VIRTQUEUE_MAX_SIZE]; > - size_t lens[VIRTQUEUE_MAX_SIZE]; > - struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE]; > + VirtQueueElement *elems[vdev->queue_max_size]; > + size_t lens[vdev->queue_max_size]; > + struct iovec mhdr_sg[vdev->queue_max_size]; > struct virtio_net_hdr_mrg_rxbuf mhdr; > unsigned mhdr_cnt = 0; > size_t offset, i, guest_offset, j; > @@ -1783,7 +1783,7 @@ static ssize_t virtio_net_receive_rcu(NetClientState > *nc, const uint8_t *buf, > > total = 0; > > - if (i == VIRTQUEUE_MAX_SIZE) { > + if (i == vdev->queue_max_size) { > virtio_error(vdev, "virtio-net unexpected long buffer chain"); > err = size; > goto err; > @@ -2532,7 +2532,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q) > for (;;) { > ssize_t ret; > unsigned int out_num; > - struct iovec sg[VIRTQUEUE_MAX_SIZE], sg2[VIRTQUEUE_MAX_SIZE + 1], > *out_sg; > + struct iovec sg[vdev->queue_max_size], sg2[vdev->queue_max_size + > 1], *out_sg; > struct virtio_net_hdr_mrg_rxbuf mhdr; > > elem = virtqueue_pop(q->tx_vq, sizeof(VirtQueueElement)); > @@ -2564,7 +2564,7 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q) > out_num = iov_copy(&sg2[1], ARRAY_SIZE(sg2) - 1, > out_sg, out_num, > n->guest_hdr_len, -1); > - if (out_num == VIRTQUEUE_MAX_SIZE) { > + if (out_num == vdev->queue_max_size) { > goto drop; > } > out_num += 1; > @@ -3364,7 +3364,8 @@ static void virtio_net_device_realize(DeviceState *dev, > Error **errp) > } > > virtio_net_set_config_size(n, n->host_features); > - virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size); > + virtio_init(vdev, "virtio-net", VIRTIO_ID_NET, n->config_size, > + VIRTQUEUE_MAX_SIZE); > > /* > * We set a lower limit on RX queue size to what it always was. > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c > index 51fd09522a..5e5e657e1d 100644 > --- a/hw/scsi/virtio-scsi.c > +++ b/hw/scsi/virtio-scsi.c > @@ -973,7 +973,7 @@ void virtio_scsi_common_realize(DeviceState *dev, > int i; > > virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI, > - sizeof(VirtIOSCSIConfig)); > + sizeof(VirtIOSCSIConfig), VIRTQUEUE_MAX_SIZE); > > if (s->conf.num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) { > s->conf.num_queues = 1; > diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c > index c595957983..ae1672d667 100644 > --- a/hw/virtio/vhost-user-fs.c > +++ b/hw/virtio/vhost-user-fs.c > @@ -220,7 +220,7 @@ static void vuf_device_realize(DeviceState *dev, Error > **errp) > } > > virtio_init(vdev, "vhost-user-fs", VIRTIO_ID_FS, > - sizeof(struct virtio_fs_config)); > + sizeof(struct virtio_fs_config), VIRTQUEUE_MAX_SIZE); > > /* Hiprio queue */ > fs->hiprio_vq = virtio_add_queue(vdev, fs->conf.queue_size, > vuf_handle_output); > diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c > index d172632bb0..eeb1d8853a 100644 > --- a/hw/virtio/vhost-user-i2c.c > +++ b/hw/virtio/vhost-user-i2c.c > @@ -220,7 +220,8 @@ static void vu_i2c_device_realize(DeviceState *dev, Error > **errp) > return; > } > > - virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0); > + virtio_init(vdev, "vhost-user-i2c", VIRTIO_ID_I2C_ADAPTER, 0, > + VIRTQUEUE_MAX_SIZE); > > i2c->vhost_dev.nvqs = 1; > i2c->vq = virtio_add_queue(vdev, 4, vu_i2c_handle_output); > diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c > index 4ad6e234ad..a81fa884a8 100644 > --- a/hw/virtio/vhost-vsock-common.c > +++ b/hw/virtio/vhost-vsock-common.c > @@ -201,7 +201,7 @@ void vhost_vsock_common_realize(VirtIODevice *vdev, const > char *name) > VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev); > > virtio_init(vdev, name, VIRTIO_ID_VSOCK, > - sizeof(struct virtio_vsock_config)); > + sizeof(struct virtio_vsock_config), VIRTQUEUE_MAX_SIZE); > > /* Receive and transmit queues belong to vhost */ > vvc->recv_vq = virtio_add_queue(vdev, VHOST_VSOCK_QUEUE_SIZE, > diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c > index 5a69dce35d..067c73223d 100644 > --- a/hw/virtio/virtio-balloon.c > +++ b/hw/virtio/virtio-balloon.c > @@ -886,7 +886,7 @@ static void virtio_balloon_device_realize(DeviceState > *dev, Error **errp) > int ret; > > virtio_init(vdev, "virtio-balloon", VIRTIO_ID_BALLOON, > - virtio_balloon_config_size(s)); > + virtio_balloon_config_size(s), VIRTQUEUE_MAX_SIZE); > > ret = qemu_add_balloon_handler(virtio_balloon_to_target, > virtio_balloon_stat, s); > @@ -909,7 +909,7 @@ static void virtio_balloon_device_realize(DeviceState > *dev, Error **errp) > s->svq = virtio_add_queue(vdev, 128, virtio_balloon_receive_stats); > > if (virtio_has_feature(s->host_features, > VIRTIO_BALLOON_F_FREE_PAGE_HINT)) { > - s->free_page_vq = virtio_add_queue(vdev, VIRTQUEUE_MAX_SIZE, > + s->free_page_vq = virtio_add_queue(vdev, vdev->queue_max_size, > > virtio_balloon_handle_free_page_vq); > precopy_add_notifier(&s->free_page_hint_notify); > > diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c > index 54f9bbb789..1e70d4d2a8 100644 > --- a/hw/virtio/virtio-crypto.c > +++ b/hw/virtio/virtio-crypto.c > @@ -810,7 +810,8 @@ static void virtio_crypto_device_realize(DeviceState > *dev, Error **errp) > return; > } > > - virtio_init(vdev, "virtio-crypto", VIRTIO_ID_CRYPTO, > vcrypto->config_size); > + virtio_init(vdev, "virtio-crypto", VIRTIO_ID_CRYPTO, > vcrypto->config_size, > + VIRTQUEUE_MAX_SIZE); > vcrypto->curr_queues = 1; > vcrypto->vqs = g_malloc0(sizeof(VirtIOCryptoQueue) * > vcrypto->max_queues); > for (i = 0; i < vcrypto->max_queues; i++) { > diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c > index 1b23e8e18c..ca360e74eb 100644 > --- a/hw/virtio/virtio-iommu.c > +++ b/hw/virtio/virtio-iommu.c > @@ -974,7 +974,7 @@ static void virtio_iommu_device_realize(DeviceState *dev, > Error **errp) > VirtIOIOMMU *s = VIRTIO_IOMMU(dev); > > virtio_init(vdev, "virtio-iommu", VIRTIO_ID_IOMMU, > - sizeof(struct virtio_iommu_config)); > + sizeof(struct virtio_iommu_config), VIRTQUEUE_MAX_SIZE); > > memset(s->iommu_pcibus_by_bus_num, 0, > sizeof(s->iommu_pcibus_by_bus_num)); > > diff --git a/hw/virtio/virtio-mem.c b/hw/virtio/virtio-mem.c > index df91e454b2..1d9d01b871 100644 > --- a/hw/virtio/virtio-mem.c > +++ b/hw/virtio/virtio-mem.c > @@ -738,7 +738,7 @@ static void virtio_mem_device_realize(DeviceState *dev, > Error **errp) > vmem->bitmap = bitmap_new(vmem->bitmap_size); > > virtio_init(vdev, TYPE_VIRTIO_MEM, VIRTIO_ID_MEM, > - sizeof(struct virtio_mem_config)); > + sizeof(struct virtio_mem_config), VIRTQUEUE_MAX_SIZE); > vmem->vq = virtio_add_queue(vdev, 128, virtio_mem_handle_request); > > host_memory_backend_set_mapped(vmem->memdev, true); > diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c > index d1aeb90a31..82b54b00c5 100644 > --- a/hw/virtio/virtio-pmem.c > +++ b/hw/virtio/virtio-pmem.c > @@ -124,7 +124,7 @@ static void virtio_pmem_realize(DeviceState *dev, Error > **errp) > > host_memory_backend_set_mapped(pmem->memdev, true); > virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM, > - sizeof(struct virtio_pmem_config)); > + sizeof(struct virtio_pmem_config), VIRTQUEUE_MAX_SIZE); > pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush); > } > > diff --git a/hw/virtio/virtio-rng.c b/hw/virtio/virtio-rng.c > index cc8e9f775d..0e91d60106 100644 > --- a/hw/virtio/virtio-rng.c > +++ b/hw/virtio/virtio-rng.c > @@ -215,7 +215,7 @@ static void virtio_rng_device_realize(DeviceState *dev, > Error **errp) > return; > } > > - virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0); > + virtio_init(vdev, "virtio-rng", VIRTIO_ID_RNG, 0, VIRTQUEUE_MAX_SIZE); > > vrng->vq = virtio_add_queue(vdev, 8, handle_input); > vrng->quota_remaining = vrng->conf.max_bytes; > diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c > index 240759ff0b..60e094d96a 100644 > --- a/hw/virtio/virtio.c > +++ b/hw/virtio/virtio.c > @@ -1419,8 +1419,8 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t > sz) > VirtIODevice *vdev = vq->vdev; > VirtQueueElement *elem = NULL; > unsigned out_num, in_num, elem_entries; > - hwaddr addr[VIRTQUEUE_MAX_SIZE]; > - struct iovec iov[VIRTQUEUE_MAX_SIZE]; > + hwaddr addr[vdev->queue_max_size]; > + struct iovec iov[vdev->queue_max_size]; > VRingDesc desc; > int rc; > > @@ -1492,7 +1492,7 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t > sz) > if (desc.flags & VRING_DESC_F_WRITE) { > map_ok = virtqueue_map_desc(vdev, &in_num, addr + out_num, > iov + out_num, > - VIRTQUEUE_MAX_SIZE - out_num, true, > + vdev->queue_max_size - out_num, true, > desc.addr, desc.len); > } else { > if (in_num) { > @@ -1500,7 +1500,7 @@ static void *virtqueue_split_pop(VirtQueue *vq, size_t > sz) > goto err_undo_map; > } > map_ok = virtqueue_map_desc(vdev, &out_num, addr, iov, > - VIRTQUEUE_MAX_SIZE, false, > + vdev->queue_max_size, false, > desc.addr, desc.len); > } > if (!map_ok) { > @@ -1556,8 +1556,8 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t > sz) > VirtIODevice *vdev = vq->vdev; > VirtQueueElement *elem = NULL; > unsigned out_num, in_num, elem_entries; > - hwaddr addr[VIRTQUEUE_MAX_SIZE]; > - struct iovec iov[VIRTQUEUE_MAX_SIZE]; > + hwaddr addr[vdev->queue_max_size]; > + struct iovec iov[vdev->queue_max_size]; > VRingPackedDesc desc; > uint16_t id; > int rc; > @@ -1620,7 +1620,7 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t > sz) > if (desc.flags & VRING_DESC_F_WRITE) { > map_ok = virtqueue_map_desc(vdev, &in_num, addr + out_num, > iov + out_num, > - VIRTQUEUE_MAX_SIZE - out_num, true, > + vdev->queue_max_size - out_num, true, > desc.addr, desc.len); > } else { > if (in_num) { > @@ -1628,7 +1628,7 @@ static void *virtqueue_packed_pop(VirtQueue *vq, size_t > sz) > goto err_undo_map; > } > map_ok = virtqueue_map_desc(vdev, &out_num, addr, iov, > - VIRTQUEUE_MAX_SIZE, false, > + vdev->queue_max_size, false, > desc.addr, desc.len); > } > if (!map_ok) { > @@ -2249,7 +2249,7 @@ void virtio_queue_set_num(VirtIODevice *vdev, int n, > int num) > * nonexistent states, or to set it to an invalid size. > */ > if (!!num != !!vdev->vq[n].vring.num || > - num > VIRTQUEUE_MAX_SIZE || > + num > vdev->queue_max_size || > num < 0) { > return; > } > @@ -2400,7 +2400,7 @@ VirtQueue *virtio_add_queue(VirtIODevice *vdev, int > queue_size, > break; > } > > - if (i == VIRTIO_QUEUE_MAX || queue_size > VIRTQUEUE_MAX_SIZE) > + if (i == VIRTIO_QUEUE_MAX || queue_size > vdev->queue_max_size) > abort(); > > vdev->vq[i].vring.num = queue_size; > @@ -3239,13 +3239,25 @@ void virtio_instance_init_common(Object *proxy_obj, > void *data, > } > > void virtio_init(VirtIODevice *vdev, const char *name, > - uint16_t device_id, size_t config_size) > + uint16_t device_id, size_t config_size, > + uint16_t queue_max_size) > { > BusState *qbus = qdev_get_parent_bus(DEVICE(vdev)); > VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus); > int i; > int nvectors = k->query_nvectors ? k->query_nvectors(qbus->parent) : 0; > > + if (queue_max_size > VIRTQUEUE_MAX_SIZE || > + !is_power_of_2(queue_max_size)) > + { > + error_report( > + "virtio: invalid queue_max_size (= %" PRIu16 "), must be a " > + "power of 2 and between 1 ... %d.", > + queue_max_size, VIRTQUEUE_MAX_SIZE > + ); > + abort(); > + } > + > if (nvectors) { > vdev->vector_queues = > g_malloc0(sizeof(*vdev->vector_queues) * nvectors); > @@ -3258,6 +3270,7 @@ void virtio_init(VirtIODevice *vdev, const char *name, > qatomic_set(&vdev->isr, 0); > vdev->queue_sel = 0; > vdev->config_vector = VIRTIO_NO_VECTOR; > + vdev->queue_max_size = queue_max_size; > vdev->vq = g_malloc0(sizeof(VirtQueue) * VIRTIO_QUEUE_MAX); > vdev->vm_running = runstate_is_running(); > vdev->broken = false; > diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h > index 8bab9cfb75..a37d1f7d52 100644 > --- a/include/hw/virtio/virtio.h > +++ b/include/hw/virtio/virtio.h > @@ -89,6 +89,7 @@ struct VirtIODevice > size_t config_len; > void *config; > uint16_t config_vector; > + uint16_t queue_max_size; > uint32_t generation; > int nvectors; > VirtQueue *vq; > @@ -166,7 +167,9 @@ void virtio_instance_init_common(Object *proxy_obj, void > *data, > size_t vdev_size, const char *vdev_name); > > void virtio_init(VirtIODevice *vdev, const char *name, > - uint16_t device_id, size_t config_size); > + uint16_t device_id, size_t config_size, > + uint16_t queue_max_size); > + > void virtio_cleanup(VirtIODevice *vdev); > > void virtio_error(VirtIODevice *vdev, const char *fmt, ...) GCC_FMT_ATTR(2, > 3);
