Re: [PATCH 1/3] KVM paravirt_ops infrastructure

Rusty Russell
2007-05-31T11:12:31Z

On Thu, 2007-05-31 at 12:40 +0200, Andi Kleen wrote:
> On Thursday 31 May 2007 12:11:16 Ingo Molnar wrote:
> >
> > * Andi Kleen <ak-l3A5Bk7waGM@public.gmane.org> wrote:
> >
> > >
> > > > > + if (wrmsr_safe(MSR_KVM_API_MAGIC, __pa(para_state), 0)) {
> > > > > + printk(KERN_INFO "KVM guest: WRMSR probe failed.\n");
> > > > > + return -ENOENT;
> > > > > + }
> > > >
> > > > How about printk(KERN_INFO "I am not a KVM guest\n");?
> > >
> > > Actually paravirt probes that fail should be silent; similar like
> > > drivers that don't find their hardware should do the same. Otherwise
> > > if there are later distro kernels with various of those compiled in
> > > the boot log would become quite noisy
> >
> > yeah. I suspect printing that it's executing in native mode is OK.
>
> But only a single printk for that please

Which already exists in paravirt.c:

static void __init default_banner(void)
{
printk(KERN_INFO "Booting paravirtualized kernel on %s\n",
paravirt_ops.name);
}
...
static int __init print_banner(void)
{
paravirt_ops.banner();
return 0;
}
core_initcall(print_banner);

Hmm, this will predate your kvm initcall tho, and making that a
pure_initcall is pretty gross...

Cheers,
Rusty.