Front-end message requests which need reply should set NEED_REPLY_MASK in flag, and response from slave need clear NEED_REPLY_MASK flag.
--- hw/virtio/vhost-user.c | 2 +- subprojects/libvhost-user/libvhost-user.c | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 00561daa06..edf2271e0a 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -1082,7 +1082,7 @@ static int vhost_user_get_u64(struct vhost_dev *dev, int request, uint64_t *u64) int ret; VhostUserMsg msg = { .hdr.request = request, - .hdr.flags = VHOST_USER_VERSION, + .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK, }; if (vhost_user_per_device_request(request) && dev->vq_index != 0) { diff --git a/subprojects/libvhost-user/libvhost-user.c b/subprojects/libvhost-user/libvhost-user.c index 9c630c2170..40f665bd7f 100644 --- a/subprojects/libvhost-user/libvhost-user.c +++ b/subprojects/libvhost-user/libvhost-user.c @@ -667,6 +667,7 @@ vu_send_reply(VuDev *dev, int conn_fd, VhostUserMsg *vmsg) { /* Set the version in the flags when sending the reply */ vmsg->flags &= ~VHOST_USER_VERSION_MASK; + vmsg->flags &= ~VHOST_USER_NEED_REPLY_MASK; vmsg->flags |= VHOST_USER_VERSION; vmsg->flags |= VHOST_USER_REPLY_MASK; -- 2.34.1