> Since backend and frontend message are synchronous in the same thread, > there will be a probability of message deadlock. > Consider each driver to determine whether to wait for response. > > Fixes: d90cf7d111ac ("vhost: support host notifier") > Cc: maxime.coquelin@redhat.com > Signed-off-by: Rma Ma > --- > v2 - fix format error in commit message > v3 - add --in-reply-to > --- Hi Maxime, This patch helps to fix vhost-user message deadlock, could you help review it? Thanks. Best wishes, Rma ________________________________ 发件人: Rma Ma 发送时间: 2023年7月4日 10:52 收件人: dpdk-dev 抄送: Maxime Coquelin ; Chenbo Xia ; Rma Ma 主题: [PATCH v3] vhost: add notify reply ops to fix message deadlock Since backend and frontend message are synchronous in the same thread, there will be a probability of message deadlock. Consider each driver to determine whether to wait for response. Fixes: d90cf7d111ac ("vhost: support host notifier") Cc: maxime.coquelin@redhat.com Signed-off-by: Rma Ma --- v2 - fix format error in commit message v3 - add --in-reply-to --- lib/vhost/vdpa_driver.h | 3 +++ lib/vhost/vhost_user.c | 23 ++++++++++++++++++----- 2 files changed, 21 insertions(+), 5 deletions(-) diff --git a/lib/vhost/vdpa_driver.h b/lib/vhost/vdpa_driver.h index 8db4ab9f4d..3d2ea3c90e 100644 --- a/lib/vhost/vdpa_driver.h +++ b/lib/vhost/vdpa_driver.h @@ -81,6 +81,9 @@ struct rte_vdpa_dev_ops { /** get device type: net device, blk device... */ int (*get_dev_type)(struct rte_vdpa_device *dev, uint32_t *type); + + /** Get the notify reply flag */ + int (*get_notify_reply_flag)(int vid, bool *need_reply); }; /** diff --git a/lib/vhost/vhost_user.c b/lib/vhost/vhost_user.c index 901a80bbaa..aa61992939 100644 --- a/lib/vhost/vhost_user.c +++ b/lib/vhost/vhost_user.c @@ -3365,13 +3365,14 @@ rte_vhost_backend_config_change(int vid, bool need_reply) static int vhost_user_backend_set_vring_host_notifier(struct virtio_net *dev, int index, int fd, uint64_t offset, - uint64_t size) + uint64_t size, + bool need_reply) { int ret; struct vhu_msg_context ctx = { .msg = { .request.backend = VHOST_USER_BACKEND_VRING_HOST_NOTIFIER_MSG, - .flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY, + .flags = VHOST_USER_VERSION, .size = sizeof(ctx.msg.payload.area), .payload.area = { .u64 = index & VHOST_USER_VRING_IDX_MASK, @@ -3388,7 +3389,13 @@ static int vhost_user_backend_set_vring_host_notifier(struct virtio_net *dev, ctx.fd_num = 1; } - ret = send_vhost_backend_message_process_reply(dev, &ctx); + if (!need_reply) + ret = send_vhost_backend_message(dev, &ctx); + else { + ctx.msg.flags |= VHOST_USER_NEED_REPLY; + ret = send_vhost_backend_message_process_reply(dev, &ctx); + } + if (ret < 0) VHOST_LOG_CONFIG(dev->ifname, ERR, "failed to set host notifier (%d)\n", ret); @@ -3402,6 +3409,7 @@ int rte_vhost_host_notifier_ctrl(int vid, uint16_t qid, bool enable) int vfio_device_fd, ret = 0; uint64_t offset, size; unsigned int i, q_start, q_last; + bool need_reply; dev = get_device(vid); if (!dev) @@ -3440,6 +3448,11 @@ int rte_vhost_host_notifier_ctrl(int vid, uint16_t qid, bool enable) if (vfio_device_fd < 0) return -ENOTSUP; + if (vdpa_dev->ops->get_notify_reply_flag == NULL) + need_reply = true; + else + vdpa_dev->ops->get_notify_reply_flag(vid, &need_reply); + if (enable) { for (i = q_start; i <= q_last; i++) { if (vdpa_dev->ops->get_notify_area(vid, i, &offset, @@ -3449,7 +3462,7 @@ int rte_vhost_host_notifier_ctrl(int vid, uint16_t qid, bool enable) } if (vhost_user_backend_set_vring_host_notifier(dev, i, - vfio_device_fd, offset, size) < 0) { + vfio_device_fd, offset, size, need_reply) < 0) { ret = -EFAULT; goto disable; } @@ -3458,7 +3471,7 @@ int rte_vhost_host_notifier_ctrl(int vid, uint16_t qid, bool enable) disable: for (i = q_start; i <= q_last; i++) { vhost_user_backend_set_vring_host_notifier(dev, i, -1, - 0, 0); + 0, 0, need_reply); } } -- 2.17.1