On Thu, Feb 13, 2020 at 11:10:15AM +0100, Ilya Maximets wrote: > On 2/13/20 12:44 AM, Flavio Leitner wrote: > > On Wed, Feb 12, 2020 at 04:31:09PM -0300, Flavio Leitner wrote: > >> On Wed, Feb 12, 2020 at 04:26:46PM +0100, Ilya Maximets wrote: > >>> On 2/10/20 8:18 PM, Flavio Leitner wrote: > >>>> Disable ECN and UFO since this is not supported yet. Also, disable > >>>> all other features when userspace_tso is not enabled. > >>> > >>> Disabling UFO saves us from receiving of a big unfragmented > >>> UDP packets, but UDP packets will still have bad checksums > >>> and will be dropped by the kernel on receive side. > >>> So, this is only part of a fix. > >> > >> Yes, this patch is not intended to fix the UDP checksum problem. > >> Unless you see a way to do that with changing the flags below. > > > > BTW, why do you think there is a problem with UDP checksum? > > We set VIRTIO_NET_HDR_F_NEEDS_CSUM which should be all it is needed. > > At least we're sending UDP packets on a wire without > requesting Tx UDP checksum offloading from HW NICs.
Packets from virtual machines relies on DPDK vhost library, and as far as I can see, it does set PKT_TX_UDP_CKSUM properly. Now for packets coming from the kernel, then netdev_linux_parse_vnet_hdr() will set that as well. Packets from userspace to kernel are properly translated by netdev_linux_prepend_vnet_hdr(). -- fbl _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
