A Fedora 7 dom0 I have crashes with null pointer dereferences in tcp_tso_segment. After upgrading to F8 this is still happening. This seems to stem from traffic shaping in a busy domU fedora mirror server. Poking around it looks like this bug http://lists.openwall.net/netdev/2007/02/09/16 Well, they fixed that by twiddling net/ipv4/netfilter/ipt_REJECT.c but I think something in my Xen enviro with a combination of a busy bridge and traffic control rules is still tripping up on net/ipv4/tcp.c line 2241 "skb = skb->next;" from what I can decypher.

I've whined about this bug on fedora-xen list.

Some links on catching a crash dump from a misbehaving kernel:

• http://fedoraproject.org/wiki/FC6KdumpKexecHowTo
• http://www.redhatmagazine.com/2007/08/15/a-quick-overview-of-linux-kerne...

Update

I finally just opened a bug with the oops output and didn't bother with getting a crash dump. I don't expect a fix for this because Fedora has decided to rebase to the current kernel. In the meantime I've disabled tc on the domU and will put a tc box in front of it if necessary.