* Lars Eggert <[EMAIL PROTECTED]> [020221 11:18] wrote: > Hi, > > I'm looking at a packet trace taken of an xl card under 4.5, and I see > bad IP and TCP/UDP checksums. The release notes state that checksumming > maybe offloaded to the NIC now, but I'd still expect them to be correct > in a packet trace! > > More specifically, the IP checksum is always zero, while the TCP and UDP > checksums are non-zero but bad. However, netstat shows no packets > arriving with bad checksums, so I assume that they get mangled somewhere > in the kernel after inbound processing. (And the machine works fine on a > network; I found this by accident.) > > Any clues?
I'm not 100% on this, but bpf may be queueing the packet without doing a deep copy of it? Another thing may be that the card performs the checksum but uses the checksum area as a scratch area? -- -Alfred Perlstein [[EMAIL PROTECTED]] 'Instead of asking why a piece of software is using "1970s technology," start asking why software is ignoring 30 years of accumulated wisdom.' Tax deductible donations for FreeBSD: http://www.freebsdfoundation.org/ To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-net" in the body of the message
