Subject: Re: 32/64bit -- Re: Ultra5?
To: Toru Nishimura <nisimura@itc.aist-nara.ac.jp>
From: Eduardo E. Horvath <eeh@one-o.com>
List: port-sparc64
Date: 03/12/2000 18:02:07
Whoah! Someone else!
> I'm new to port-sparc64, and have little knowledge of past progress of
> NetBSD/sparc64.
>
> > But remember the most important rule: do not mix 32-bit and 64-bit
> > kernels and userlands. A 64-bit kernel may limp along for a short
> > time on a 32-bit userland before it dies, but a 32-bit kernel will
> > immediately fail on a 64-bit userland.
>
> What's the issue in NetBSD/sparc64 of 32bit userland support by 64bit
> kernel? Is it a technical difficulty or lack of imformation?
It's a technical problem. You need to run with COMPAT_NETBSD32 to
have it work at all. There are some system calls (mostly sysv IPC and
sysctl) that must be completely reimplemented in COMPAT_NETBSD32.
Then there are a suprizing number of programs that are kernel memory
grovellers, like ps. How is a 32-bit application going to map in and
make any sense of 64-bit kernel datastructures? I don't know. Want
to work on it?
=========================================================================
Eduardo Horvath eeh@netbsd.org
"I need to find a pithy new quote." -- me