Herbert Xu wrote: > Hi Dave: > > [NET]: Allow forwarding of ip_summed except CHECKSUM_COMPLETE > > Right now Xen has a horrible hack that lets it forward packets with > partial checksums. One of the reasons that CHECKSUM_PARTIAL and > CHECKSUM_COMPLETE were added is so that we can get rid of this hack > (where it creates two extra bits in the skbuff to essentially mirror > ip_summed without being destroyed by the forwarding code). > > I had forgotten that I've already gone through all the deivce drivers > last time around to make sure that they're looking at ip_summed == > CHECKSUM_PARTIAL rather than ip_summed != 0 on transmit. In any case, > I've now done that again so it should definitely be safe. > > Unfortunately nobody has yet added any code to update CHECKSUM_COMPLETE > values on forward so we I'm setting that to CHECKSUM_NONE. This should > be safe to remove for bridging but I'd like to check that code path > first. > > So here is the patch that lets us get rid of the hack by preserving > ip_summed (mostly) on forwarded packets.
Just wondering, how does Xen know whether a packet will be forwarded? The input path doesn't seem to deal with CHECKSUM_PARTIAL correctly, ip_defrag for example resets them to CHECKSUM_NONE, so further checks will fail, others seem to either ignore them or handle them together with CHECKSUM_NONE. - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
