Re: [PATCH/RFC 7/9] Virtual network guest device driver

Eric Van Hensbergen
2007-05-22T12:49:51Z

On 5/22/07, Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org> wrote:
> Anthony Liguori wrote:
> >>
> >> In a PV environment why not just pass an initial cookie/hash/whatever
> >> as a command-line argument/register/memory-space to the underlying
> >> kernel?
> >>
> >
> > You can't pass a command line argument to Windows (at least, not easily
> > AFAIK). You could get away with an MSR/CPUID flag but then you're
> > relying on uniqueness which isn't guaranteed.
> >
>
> In the general case, you can't pass a command line argument to Linux
> either. kvm doesn't boot Linux; it boots the bios, which boots the boot
> sector, which boots grub, which boots Linux. Relying on the user to
> edit the command line in grub is wrong.
>

I didn't think we were talking about the general case, I thought we
were discussing the PV case. In the PV case, having bios/bootloader
is unnecessary overhead. To that same end, I don't see Windows in the
PV case unless they magically want to to coordinate PV standards with
us, in which case we certainly can negotiate a more sane discovery
mechanism.

-eric