Subject: Re: kernel: alignment fault trap on sparc
To: Eduardo Horvath <>
From: Manuel Bouyer <>
List: tech-kern
Date: 06/07/2004 19:57:25
On Sat, Jun 05, 2004 at 07:16:25PM +0000, Eduardo Horvath wrote:
> > No idea how this instruction could cause an alignment trap.
> sethi %hi(0xf02e3000), %l6 cannot generate an alignment fault.  Only loads or 
> stores or possibly some sort of branches can generate alignment faults.
> You can try disassembling a few instructions surrounding the one that allegedly
> caused the trap and see if one of them was the real culprit.  

How can I do that ? I didn't find anything in ddb to do disassembly, but I
probably missed something.

> Otherwise, it could be that the instruction in the instruction cache does not
> match the contents in memory,

Software bug ? we have had cache issues on sun4c in the past ...

> or your CPU is getting old and flakey.  I've seen
> this happen a lot with old machines.

I didn't have much problems with sparc yet. And this box started doing this
right after the upgrade, it was solid under 1.6.2.

Anyway I've set up a SS2 to try to reproduce this.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference