Re: [Xen-users] Integrating xen into existing kernel build processes

[Ralph Passgang <ralph@xxxxxxxxxxxxx>]

Hi,

you are using debian, so I would suggest the following to compile a xen3 
kernel:

put the following line in your /etc/apt/sources.list
"deb http://packages.debianbase.de/sarge/i386/xen3 ./"
(replace sarge with etch/sid if you are not using sarge(stable))

then run:
"apt-get update && apt-get install linux-patch-xen"

then you can donload a vanilla 2.6.12 kernel, for example with this line:
"wget ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-2.6.12.tar.bz2";
unpack the archive and chdir in it, then you can apply the xen-kernel patch 
with the following command:
"/usr/src/kernel-patch/i386/apply/xen"
this will patch the vanilla 2.6.12 kernel to a 2.6.12.6-xen kernel.
Now you can change the configuration of the kernel (if you like) with:
"make ARCH=xen menuconfig"
after that you can compile and package it with the following comand:
"make-kpkg --revision myversion1 --append_to_version .6-xen --arch xen 
kernel_image".
After this is completed you can install the new xen-kernel deb. You have to 
create a initrd yourself, because the make-kpkg doesn't handle that for xen 
kernel-packages. The initrd can be created with:
"mkinitrd -o /boot/xen-modules-2.6.12.6-xen 2.6.12.6-xen"

But that is just the reuired steps for the kernel package, if you want to 
install xen3 on your debian box you should also make this:
"apt-get install xen bridge-utils"
(bridge-utils is only needed if you want to use a bridged network and not a 
routed one)

Last but not least you need an entry in your /boot/grub/menu.lst to boot xen3. 
THe following lines should do the trick:
"title           Xen 3 - Kernel 2.6.12-xen0
root            (hd0,6)
kernel          /boot/xen.gz
module          /boot/vmlinuz-2.6.12.6-xen root=/dev/hda7 ro
module          /boot/modules-2.6.12.6-xen
savedefault
boot"
(you may have to change "(hd0,6)" and "hda7" to your root-device.)

Hope this helped :)

--Ralph

Am Donnerstag, 5. Januar 2006 10:17 schrieb Marc Haber:
> Hi,
>
> I have an elaborate procedure to build new kernels and out-of-tree
> modules in differently patched versions and configurations. This
> procedure is based on Debians kernel build procedures, using
> kernel-package, which can automatically apply and back out patches
> delivered in a kind of specialized format as Debian packages. Now, I
> would like to introduce Xen 3.x into that game.
>
> I do not have practical experience with Xen yet, and I am far away
> from being a kernel hacker.
>
> Since Xen uses its own kernel build mechanism, a few questions have
> surfaced, and I'd appreciate if somebody could take the time to answer.
>
>
>
> (1)
> In the Xen sources, there is a sparsely populated kernel tree, and a
> set of patches. The build process downloads a linux 2.6.12 from
> kernel.org and builds a symlink farm to connect the sparse tree and the
> pristine upstream tree to each other before invoking the actual build.
>
> (1a)
> Did I correctly understand this?
>
> (1b)
> Where do the patches play in that game? Are they applied to the
> pristine upstream tree, or to the resulting link farm?
>
> (1c)
> How does the build process determine that 2.6.12 is the kernel versio
> that should be built?
> Is it the setting in buildconfigs/mk.linux-2.6-*?
>
> (1d)
> What is the recommended way to generate a linux-2.6.12-xen.tar.bz2
> kernel tree?
>
>
>
> (2)
> The sparse tree is around 4 MB large, and contains both new files and
> files that already exist in the pristine upstream tree.
>
> (2a)
> Do I see correctly that some upstream files are completely replaced by
> the ones that come from the sparse xen tree?
>
> (2b)
> Why was this method of distribution chosen over a more conservative
> kernel patch?
>
> (2c)
> Do I see correctly that the patch is so invasive that the chance to
> successfully xenize a more current kernel like 2.6.14 or even .15
> without both intimate knowledge of Xen and the kernel is quite near zero?
>
>
>
> (3)
> How do I protect my Xenized kernel against the
> local-privilege-escalation-exploit-of-the-week which keep surfacing
> too often these days?
>
> (3a)
> Is there (unofficial?) support of later kernels for Xen 3.x without
> having to resort to unstable or testing Xen versions?
>
> (3b)
> Is there (unofficial?) security support for the xenized 2.6.12 kernel
> that is built by the Xen 3.x stable build process?
>
> (3c)
> Or do I have to sift through the lkml myself, deciding which patches
> are security relevant or not?
>
> (3d)
> How do other people address the issue of kernel security with Xen?
>
>
>
> Thanks for your consideration, I'd appreciate answers, pointers to
> docs, and maybe even discussion.
>
> Greetings
> Marc

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users