There are two kernel image formats - vmlinuz is just a gzip compressed ELF file, whereas bzImage is a more complicated format where the gzip compressed ELF image is part of the payload. Xen has long used the vmlinuz format. Our other kernels use the bzImage format. The kernel-xen package is being removed in Fedora 10 and kernel-PAE.i686/kernel.x86_64 are now the kernels used for booting Xen DomU. However, these packages ship a bzImage format kernel, and RHEL5 Xen's libxc does not have support for booting such images. Support was added to upstream xen in April: http://lists.xensource.com/archives/html/xen-devel/2008-04/msg00525.html And we're including that patch now in F-8, F-9 and F-10. The patch is fairly simple and self-contained. It hasn't caused any regressions that we know of yet.
Created attachment 312973 [details] xen-3.1.0-bzimage.patch
I tested this patch out on an i386 box. Basically, inside the guest I checked out the latest LKML sources and did "make ; make install" (which installs the bzImage). I then attempted to boot the kernel. Before this patch, I got "invalid format" when trying to boot. After this patch, the newly built kernel started to boot (although it crashed and burned later on for other, unrelated reasons). Chris Lalancette
* Mon Aug 18 2008 Mark McLoughlin <markmc> - 3.0.3-70.el5 - Support booting bzImage xen pv_ops kernels (e.g. Fedora 10) (rhbz #457199)
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2009-0118.html