From: Ilya Maximets Date: Thu, 17 Oct 2019 15:00:19 +0000 (+0200) Subject: vhost: disable host TSO for linear buffers without extbuf X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=70c7747689082abba6452803b6e23e6aed649ace;p=dpdk.git vhost: disable host TSO for linear buffers without extbuf If linear buffers requested and external buffers are not, vhost will not be able to receive any buffer that doesn't fit in a single mbuf. Moreover, if such a buffer will appear in a vring it will never be dequeued and the whole vring will become dead breaking the network connection. Disable segmentation offloading from the host side to avoid having such a big buffers. Fixes: c3ff0ac70acb ("vhost: improve performance by supporting large buffer") Signed-off-by: Ilya Maximets Reviewed-by: Maxime Coquelin --- diff --git a/lib/librte_vhost/socket.c b/lib/librte_vhost/socket.c index 2d3d208049..a34bc7f9a3 100644 --- a/lib/librte_vhost/socket.c +++ b/lib/librte_vhost/socket.c @@ -933,6 +933,24 @@ rte_vhost_driver_register(const char *path, uint64_t flags) ~(1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT); } + /* + * We'll not be able to receive a buffer from guest in linear mode + * without external buffer if it will not fit in a single mbuf, which is + * likely if segmentation offloading enabled. + */ + if (vsocket->linearbuf && !vsocket->extbuf) { + uint64_t seg_offload_features = + (1ULL << VIRTIO_NET_F_HOST_TSO4) | + (1ULL << VIRTIO_NET_F_HOST_TSO6) | + (1ULL << VIRTIO_NET_F_HOST_UFO); + + RTE_LOG(INFO, VHOST_CONFIG, + "Linear buffers requested without external buffers, " + "disabling host segmentation offloading support\n"); + vsocket->supported_features &= ~seg_offload_features; + vsocket->features &= ~seg_offload_features; + } + if (!(flags & RTE_VHOST_USER_IOMMU_SUPPORT)) { vsocket->supported_features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM); vsocket->features &= ~(1ULL << VIRTIO_F_IOMMU_PLATFORM);