Hi, Thanks for finding these bugs! I'll post an updated version soon (2 patches with no separate Kconfig patches, one LRO and one eHEA patch). See comments below.
Thanks, Jan-Bernd On Monday 30 July 2007 22:32, Andrew Gallatin wrote: > I was working on testing the myri10ge patch, and I ran into a few > problems. I've attached a patch to inet_lro.c to fix some of them, > and a patch to myri10ge.c to show how to use the page based > interface. Both patches are signed off by Andrew Gallatin > <[EMAIL PROTECTED]> > > First, the LRO_MAX_PG_HLEN is still a problem. Minimally sized 60 > byte frames still cause problems in lro_gen_skb due to skb->len > going negative. Fixed in the attached patch. It may be simpler > to just drop LRO_MAX_PG_HLEN to ETH_ZLEN, but I'm not sure if > that is enough. Are there "smart" NICs which might chop off padding > themselves? I'd tend to stick to an explicit check as implemented in your patch for now > > Second, you still need to set skb->ip_summed = CHECKSUM_UNNECESSARY > when modified packets are flushed, else the stack will see bad > checksums for packets from CHECKSUM_COMPLETE drivers using the > skb interface. Fixed in the attached patch. I thought about it... As we do update the TCP checksum for aggregated packets we could add a second ip_summed field in the net_lro_mgr struct used for aggregated packets to support HW that does not have any checksum helper functionality. These drivers could set this ip_summed field to CHECKSUM_NONE, and thus leave the checksum check to the stack. I'm not sure if these old devices benefit a lot from LRO. So what do you think? > > Fourth, I did some traffic sniffing to try to figure out what's going > on above, and saw tcpdump complain about bad checksums. Have you tried > running tcpdump -s 65535 -vvv? Have you also seen bad checksums? > I seem to see this for both page- and skb-based versions of the driver. > Hmmm, can't confirm that. For our skb-based version I see correct checksums for aggregated packets and for the page-based version as well. I used: (tcpdump -i ethX -s 0 -w dump.bin) in combination with ethereal. Don't see problems as well with your tcpdump command. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
