On Tue, Nov 13, 2018 at 10:01 AM Willem de Bruijn <willemdebruijn.ker...@gmail.com> wrote: > > On Mon, Nov 12, 2018 at 2:49 PM Cong Wang <xiyou.wangc...@gmail.com> wrote: > > > > Currently netdev_rx_csum_fault() only shows a device name, > > we need more information about the skb for debugging csum > > failures. > > > > Sample output: > > > > ens3: hw csum failure > > dev features: 0x0000000000014b89 > > skb len=84 data_len=0 pkt_type=0 gso_size=0 gso_type=0 nr_frags=0 > > ip_summed=0 csum=0 csum_complete_sw=0 csum_valid=0 csum_level=0 > > Recent issues were protocol dependent, including whether vlan headers > were present. Perhaps also print skb vlan fields and even the first N > bytes of data to inspect protocol headers? Also skb_iif, esp. if this > differs from dev->ifindex.
Pawel's case seems to be vlan related, however, as I mentioned, my case is neither vlan nor RXFCS related. Ideally, we should dump the whole packet in order to verify the correctness of the checksum. :) It is not easy to do so given how complex an skb is now. This is why I only select a few skb fields to dump. I am pretty sure this can't cover all cases, you can always add more for your need in the future. Thanks.
