This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
Home Products Support Community News


Re: [Xen-devel] Re: [PATCH] Fix __XEN_INTERFACE_VERSION__ old config bre

On 7 Apr 2006, at 08:48, Magnus Damm wrote:

Does this lead to a kernel that actually works (e.g., can you sgut it
down without crashing)? I doubt it.

I use a kernel config without CONFIG_XEN_INTERFACE_VERSION, and
building and running dom0 on x86 (in qemu) seems ok to me.

I tried 'xm save' on such a domU and that doesn't work. The reason is that the kernel tree expects to be calling the new sched_op hypercall, but because the interface version gets defined to zero, it actually calls the old sched_op hypercall which takes different arguments. I also tried rebooting such a domU and that doesn't work (the guest is killed but not restarted) -- again because the old and new sched_op hypercall take their arguments in different ways.

These problems are somewhat hidden I suppose, since you can boot and run happily with the domain for the most part, but it illustrates that if a guest is defining an obviously interface version we should fail the build, not build some inconsistent combination of guest kernel and hypervisor interface!

 -- Keir

Xen-devel mailing list