Re: [PATCH 3/6] lguest suppress IDE probing

Rusty Russell
2007-06-06T01:11:41Z

On Tue, 2007-06-05 at 17:07 +0100, Alan Cox wrote:
> On Wed, 06 Jun 2007 00:58:03 +1000
> Rusty Russell <rusty@rustcorp.com.au> wrote:
>
> > The IDE probe is the slowest part of boot: by suppressing it we cut
> > boot from from 3 seconds to half a second.
>
> NAK NAK NAK NAK NAK

Hi Alan!

> > AFAICT, the commandline is the easiest way to suppress the probing.
>
> Gaa ... Rusty surely you have more taste than that.

Indeed, but it got attention 8)

> See include/asm-foo/ide.h
>
> Add an lguest check to go with the pci check and for the lguest case just
> say "no controllers"

Actually, Jeremy suggested claiming the entire IO space. That works for
Xen domU too, and makes some amount of sense.

> Better yet just don't compile in the old IDE stuff, lguest doesn't have a
> PCI or ISA bus anyway.

Sure, but the "run the same kernel as guest and host" is a really nice
feature.

> Alternatively make the IDE I/O space return 0xFF and it'll skip them
> anyway.

Hmm, every "in" should be returning 0xFFs, but I still get the delay and
the probing. Xen domU gets it too.

Thanks!
Rusty.