compile PF in a DomU kernel?

[Philip <subs%christiantena.net@localhost>]

Hello

I need to be able to use PF in a DomU kernel, but after some time trying
and failing my understanding is that LKM doesn't work in a DomU, and I
suppose modules have to be loaded with the kernel by Dom0 and all that?
In fact when I tried the DomU hung and I had to mount the image file and
change the rc.conf back before I could boot it.

I'm not a xen expert at all as you can probably see.....

I'm thanking that the easiest thing to do is to compile a new DomU
kernel with PF support built in, so that LKM isn't needed.

Can anyone give me some guidance?  I have compiled Netbsd kernels before
but not xen ones.

I am running Netbsd 5.0.1 as both Dom0 and DomU and I'm using xen3.
It's all prebuilt binary i386 packages.
I think my domu is the one from
http://ftp.netbsd.org/pub/NetBSD/NetBSD-5.0.1/i386/binary/kernel/netbsd-XEN3_DOMU.gz

I have read http://www.netbsd.org/docs/kernel/ and I'm guess that I use
the conf file from cd /usr/src/sys/arch/<ARCH>/conf with conf=xen, keep
everything the same but just add "options       PFIL_HOOKS      # pfil(9) packet
filter hooks" as it says at http://www.netbsd.org/docs/network/pf.html
or are there some other tricks?

or maybe there's some other way that's easier...

thanks for any help, Philip