Re: [patch 14/21] Xen-paravirt: Add XEN config options and disable unsupported config options.

Andrew Morton
2007-02-16T07:07:17Z

On Thu, 15 Feb 2007 22:14:45 -0800 Dan Hecht <dhecht@vmware.com> wrote:

> > config PREEMPT
> > bool "Preemptible Kernel (Low-Latency Desktop)"
> > + depends on !XEN
> > help
> > This option reduces the latency of the kernel by making
> > all kernel code (that is not executing in a critical section)
> >

Oh, so that's why it doesn't break when CONFIG_PREEMPT=y. In which case
that preempt_disable() I spotted is wrong-and-unneeded.

Why doesn't Xen work with preemption??

> I hate to sound like a broken record, but this really isn't the right
> way to do this. If you are going to inhibit config settings when Xen
> support is compiled, then it should be:
>
> config XEN
> depends on !KEXEC && !DOUBLEFAULT && HZ_100 && !PREEMPT
>

Agree.