9944bddf80
vhost_new_device might be called in different threads at the same time. thread 1(config thread) rte_vhost_driver_start ->vhost_user_start_client ->vhost_user_add_connection -> vhost_new_device thread 2(vhost-events) vhost_user_read_cb ->vhost_user_msg_handler (return value < 0) -> vhost_user_start_client -> vhost_new_device So there could be a case that a same vid has been allocated twice, or some vid might be lost in DPDK lib however still held by the upper applications. Another place where race would happen is at the func *vhost_destroy_device*, but after a detailed investigation, the race does not exist as long as no two devices have the same vid: Calling vhost_destroy_devices in different threads with different vids is actually safe. Fixes: a277c7159876 ("vhost: refactor code structure") Cc: stable@dpdk.org Reported-by: Peng He <hepeng.0320@bytedance.com> Signed-off-by: Fei Chen <chenwei.0515@bytedance.com> Reviewed-by: Zhihong Wang <wangzhihong.wzh@bytedance.com> Reviewed-by: Chenbo Xia <chenbo.xia@intel.com>