For now DPDK assumes that callfd, kickfd and last_idx are being set just once during vring initialization and device cannot be running while DPDK receives SET_VRING_KICK, SET_VRING_CALL and SET_VRING_BASE messages. However, that assumption is wrong. For Vhost SCSI messages might arrive at any point of time, possibly multiple times, one after another.
QEMU issues SET_VRING_CALL once during device initialization, then again during device start. The second message will close previous callfd, which is still being used by the user-implementation of vhost device. This results in writing to invalid (closed) callfd. Other messages like SET_FEATURES, SET_VRING_ADDR etc also will change internal state of VQ or device. To prevent race condition device should also be stopped before updateing vring data. Signed-off-by: Dariusz Stojaczyk <dariuszx.stojac...@intel.com> Signed-off-by: Pawel Wodkowski <pawelx.wodkow...@intel.com> Signed-off-by: Tomasz Kulasek <tomaszx.kula...@intel.com> --- lib/librte_vhost/vhost_user.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index 65ee33919..3895e6edd 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -172,6 +172,10 @@ vhost_user_set_features(struct virtio_net *dev, uint64_t features) if (dev->notify_ops->features_changed) dev->notify_ops->features_changed(dev->vid, features); + else { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } } dev->features = features; @@ -487,6 +491,12 @@ vhost_user_set_vring_addr(struct virtio_net **pdev, VhostUserMsg *msg) if (dev->mem == NULL) return -1; + /* Remove from the data plane. */ + if (dev->flags & VIRTIO_DEV_RUNNING) { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } + /* addr->index refers to the queue index. The txq 1, rxq is 0. */ vq = dev->virtqueue[msg->payload.addr.index]; @@ -517,6 +527,12 @@ static int vhost_user_set_vring_base(struct virtio_net *dev, VhostUserMsg *msg) { + /* Remove from the data plane. */ + if (dev->flags & VIRTIO_DEV_RUNNING) { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } + dev->virtqueue[msg->payload.state.index]->last_used_idx = msg->payload.state.num; dev->virtqueue[msg->payload.state.index]->last_avail_idx = @@ -796,6 +812,12 @@ vhost_user_set_vring_call(struct virtio_net *dev, struct VhostUserMsg *pmsg) struct vhost_vring_file file; struct vhost_virtqueue *vq; + /* Remove from the data plane. */ + if (dev->flags & VIRTIO_DEV_RUNNING) { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } + file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK) file.fd = VIRTIO_INVALID_EVENTFD; @@ -818,6 +840,12 @@ vhost_user_set_vring_kick(struct virtio_net **pdev, struct VhostUserMsg *pmsg) struct vhost_virtqueue *vq; struct virtio_net *dev = *pdev; + /* Remove from the data plane. */ + if (dev->flags & VIRTIO_DEV_RUNNING) { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } + file.index = pmsg->payload.u64 & VHOST_USER_VRING_IDX_MASK; if (pmsg->payload.u64 & VHOST_USER_VRING_NOFD_MASK) file.fd = VIRTIO_INVALID_EVENTFD; @@ -959,6 +987,12 @@ vhost_user_set_protocol_features(struct virtio_net *dev, if (protocol_features & ~VHOST_USER_PROTOCOL_FEATURES) return; + /* Remove from the data plane. */ + if (dev->flags & VIRTIO_DEV_RUNNING) { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } + dev->protocol_features = protocol_features; } @@ -981,6 +1015,12 @@ vhost_user_set_log_base(struct virtio_net *dev, struct VhostUserMsg *msg) return -1; } + /* Remove from the data plane. */ + if (dev->flags & VIRTIO_DEV_RUNNING) { + dev->flags &= ~VIRTIO_DEV_RUNNING; + dev->notify_ops->destroy_device(dev->vid); + } + size = msg->payload.log.mmap_size; off = msg->payload.log.mmap_offset; RTE_LOG(INFO, VHOST_CONFIG, -- 2.14.1