diff --git a/Documentation/topics/dpdk/vhost-user.rst b/Documentation/topics/dpdk/vhost-user.rst index 4bc5aef59d8..f53ff3fc708 100644 --- a/Documentation/topics/dpdk/vhost-user.rst +++ b/Documentation/topics/dpdk/vhost-user.rst @@ -556,6 +556,11 @@ shown with:: vhost-user Dequeue Zero Copy (experimental) ------------------------------------------- +.. warning:: + + vhost-user Dequeue Zero Copy is deprecated in OVS and will be removed in + the next release. + Normally when dequeuing a packet from a vHost User device, a memcpy operation must be used to copy that packet from guest address space to host address space. This memcpy can be removed by enabling dequeue zero-copy like so:: diff --git a/NEWS b/NEWS index 43dde98a3d5..d2b8b6630a4 100644 --- a/NEWS +++ b/NEWS @@ -18,6 +18,8 @@ v2.14.0 - xx xxx xxxx CVE-2020-10726, this DPDK version is strongly recommended to be used. * New 'ovs-appctl dpdk/log-list' and 'ovs-appctl dpdk/log-set' commands to list and change log levels in DPDK components. + * Vhost-user Dequeue zero-copy support is deprecated and will be removed + in the next release. - Linux datapath: * Support for kernel versions up to 5.5.x. - AF_XDP: diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c index b940b1ac25b..18c4adcc773 100644 --- a/lib/netdev-dpdk.c +++ b/lib/netdev-dpdk.c @@ -5085,6 +5085,8 @@ netdev_dpdk_vhost_client_reconfigure(struct netdev *netdev) dev->up.name, dev->vhost_id); if (zc_enabled) { VLOG_INFO("Zero copy enabled for vHost port %s", dev->up.name); + VLOG_WARN("Zero copy support is deprecated and will be " + "removed in the next OVS release."); } }