Subject: Re: sysctl questions
To: FUKAUMI Naoki <fun@naobsd.org>
From: Christian Limpach <chris@pin.lu>
List: port-xen
Date: 05/08/2004 19:44:29
Hi,

On Sun, May 09, 2004 at 12:34:05AM +0900, FUKAUMI Naoki wrote:
> % sysctl machdep
> sysctl: machdep.diskinfo: sysctl() failed with Bad address
> 
> Is this a bug?

I get this on NetBSD/i386 as well.

> machdep.fpu_present = 1
> machdep.osfxsr = 0
> machdep.sse = 0
> machdep.sse2 = 0
> 
> Can I use SSE/SSE2 cpu features on NetBSD/xen?

I've disabled FXSAVE/FXRESTOR because npx.c uses a different dna
routine in that case.  The npxdna_xmm routine needs to be fixed
first before you can use FXSAVE/FXRESTOR.  And detecting SSE/SSE2
is conditional on the presence of FXSR.  Also I'm not sure if/how
you can enable SSE/SSE2 if Xen doesn't enable it for you anyway.

> machdep.domain0.diskcookie.wd0 = 768
> machdep.domain0.diskcookie.cd0 = 5632
> 
> What is this?

These are the "cookies" Xen uses to identify disks.  They are
usually hidden within the kernel because only the block device
driver needs to know the cookie when requesting a transfer
from Xen.  In domain0 the above sysctl nodes are created so
that the domain tools can create virtual block devices.

    christian