From 7611d5d9e741edaea473a5db4a0f6cba39d4227e Mon Sep 17 00:00:00 2001 From: Steven Luong Date: Thu, 30 Jan 2020 15:18:45 -0800 Subject: virtio: vhost gso is broken in some topology Recent modification added a call to vnet_gso_header_offset_parser in the beginning of vhost_user_handle_tx_offload. The former routine may set tcp or udp->checksum to 0. While it is appropriate to set it to 0 for the GSO packet, it is broken and causes checksum error if the aformentiooned routine is called by a non-GSO packet. The fix is to not call vhost_user_handle_tx_offload if the buffer does not indicate checksum offload is needed. Type: fix Signed-off-by: Steven Luong Change-Id: I6e699d7a40b7887ff149cd8f77e8f0fa9374ef19 (cherry picked from commit 564e1672917e205d7ae79525bb937df18f8d764b) --- src/vnet/devices/virtio/vhost_user_output.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/src/vnet/devices/virtio/vhost_user_output.c b/src/vnet/devices/virtio/vhost_user_output.c index a47583d64fa..c1b8fe1a92a 100644 --- a/src/vnet/devices/virtio/vhost_user_output.c +++ b/src/vnet/devices/virtio/vhost_user_output.c @@ -307,6 +307,7 @@ VNET_DEVICE_CLASS_TX_FN (vhost_user_device_class) (vlib_main_t * vm, u8 retry = 8; u16 copy_len; u16 tx_headers_len; + u32 or_flags; if (PREDICT_FALSE (!vui->admin_up)) { @@ -400,8 +401,13 @@ retry: hdr->hdr.gso_type = VIRTIO_NET_HDR_GSO_NONE; hdr->num_buffers = 1; //This is local, no need to check - /* Guest supports csum offload? */ - if (vui->features & (1ULL << FEAT_VIRTIO_NET_F_GUEST_CSUM)) + or_flags = (b0->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM) || + (b0->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM) || + (b0->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM); + + /* Guest supports csum offload and buffer requires checksum offload? */ + if (or_flags + && (vui->features & (1ULL << FEAT_VIRTIO_NET_F_GUEST_CSUM))) vhost_user_handle_tx_offload (vui, b0, &hdr->hdr); // Prepare a copy order executed later for the header -- cgit 1.2.3-korg