On Sat, 31 Aug 2024 00:43:11 +0000 Mina Almasry wrote: > +The socket must be flow steered to the dmabuf bound RX queue:: > + > + ethtool -N eth1 flow-type tcp4 ... queue 15, nit: tailing comma here > +Devmem payloads are inaccessible to the kernel processing the packets. This > +results in a few quirks for payloads of devmem skbs: > + > +- Loopback is not functional. Loopback relies on copying the payload, which is > + not possible with devmem skbs. > + > +- Software checksum calculation fails. Speaking of which, I think we need to add readability check to skb_checksum_help(). Shouldn't the check in __skb_checksum() have a WARN_ON_ONCE() around it? It's impossible to return an error from there. > +- TCP Dump and bpf can't access devmem packet payloads. > + > + > +Testing > +======= > + > +More realistic example code can be found in the kernel source under > +tools/testing/selftests/net/ncdevmem.c looks like HTML output wraps the file path, maybe quote it as ``tools/testing/selftests/net/ncdevmem.c`` ?