[CentOS] Strange Xen problem

Mon Mar 24 22:12:30 UTC 2008
Louis Lagendijk <louis at lagendijk.xs4all.nl>

I have a strange problem when using Centos:
When using a Xen kernel (it does not matter whether a guest is started
or not) networking fails is flakey.
ssl connections fail, ping reports a 
wrong data byte #50 .....

I am using a Sun quad ethernet card, but when I tried the gigabit
Ethernet on the motherboard, I do not get the error reports from ping,
but many missing replies instead.
The behaviour is somewhat intermittent. But now I am using a non-Xen
kernel I have no problems. there is nothing logged in /var/log/messages.

I had to patch the kernel due to some missing initialisation in the sun
hme driver, but as said above there are errors on other cards as well.
I am probably overlooking something obvious, but hours of googling have
not given any results.

Any hints anybody?

Louis