Subject: Re: "-mcpu=21264a" for kernel compile?
To: Michael Kukat <>
From: Tobias Nygren <>
List: port-alpha
Date: 12/12/2004 12:15:16
On Sun, 12 Dec 2004 12:01:19 +0100 (CET)
Michael Kukat <> wrote:

> Hi !
> On Sun, 12 Dec 2004, Hiroshi Hakoyama wrote:
> > Can I use the flag "-mcpu=21264a" safely for kernel compile?
> > /usr/pkg/bin/cpuflags provides this flag for my box, UP1000. I am not
> > sure, but a kernel compiled without "-mcpu=21264a" seems to be more
> > stable on the box.
> I use -mcpu=ev56 on my Miata since a while, i even compiled the whole 2.0
> userland with this. No problems so far. Just try it :)
> > When I tried to compile a GENERIC kernel (# ./ tools
> > kernel=GENERIC), a kernel of NetBSD 2.0 compiled with "-mcpu=21264a" on
> > UP1000  showed following kernel panic. This kernel panic may be related
> > to send-pr #27139 (I also used "-mcpu=21264a" for kernel compile).
> If you get into trouble with those optimizations, just try the next lower
> level. As said, EV56 works fine here.
> ...Michael

Hi all,

I tried a 2.0 -mcpu=21164pc kernel yesterday. It seems everything works ok,
except when an unaligned access occurs in userland and machdep.unaligned_fix=1.
Then after the exception handling the kernel will crash. (repeatable by trying
to run for instance chat/centericq).
I'll try to find out wether or not this is pca56 specific.