Subject: Re: fp disabled trap, IPC
To: None <port-sparc@netbsd.org>
From: Matt <matt@vertrauen.org>
List: port-sparc
Date: 05/24/2001 00:18:39
On Tue, May 22, 2001 at 09:22:06PM -0500, John Towler wrote:
> 
> I have a number of times encountered kernel panics along the lines of
> the following while running NetBSD 1.{4.[23],5,5.1}.  
> 
> 
> Trap type 0x4:	pc= 0xf000ab94
> 		npc=0xf0000ab98
> 		psr=4010c2<EF,S,PS>
> 
> kernel: fp disabled trap stopped in sh 
> 	at special_fp_store+0x18: std %f2, [%o0+0x8]
> 
> 
> This one was encountered running NetBSD-1.4.3 (11-02/4-2000 snapshot)
> whilst doing a make build in the background of the 12-4 src tree.
> 
> or
> 
>  Panic: fp exception, FPU disabled
> 			or EF bit set to 0, but FPU disabled 
> 
> with a system crash and it drops you into the PROM. 
> 
> 
> Is this kind of thing specific to my box, (the IPC is old, perhaps a
> hardware problem?) or does this happen to others?  What do I need to
> understand about how NetBSD intends things to be done to solve this
> problem.  The src tree is not so very small, where ought I to begin
> looking to see how this fpu-disabled-trap is set up and such so that I
> can better recover from the possible sources of this type of problem.

According to the hardware docs, the IPC has a FPU. Look at the sparc
arch spec on www.sparc.com, d/l the v8 spec, look for EF, and PSR. This
should give you a little insight on whats happening. Look in
/usr/src/sys/arch/sparc/sparc/trap.c I think....