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To: Charles Henrich <henrich@crh.cl.msu.edu>
Cc: jgreco@brasil.moneng.mei.com, freebsd-hackers@freebsd.org,
        dyson@freebsd.org
Subject: Re: CVSup
In-reply-to: <199610091424.KAA04600@crh.cl.msu.edu>
Date: Wed, 09 Oct 1996 19:16:18 -0700
From: John Polstra <jdp@polstra.com>
Sender: owner-hackers@freebsd.org
X-Loop: FreeBSD.org
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> It appears to run (spiffy little tool!) but I billions (okay hundreds :) of:
> 
> fatal process exception: page fault, fault VA = 0x4d9a98
> fatal process exception: page fault, fault VA = 0x3e080c
> fatal process exception: page fault, fault VA = 0x4db3c0
> fatal process exception: page fault, fault VA = 0x3663c0
> ...
> Any hints out there?

I poked around some.  This message comes from src/sys/i386/i386/trap.c:

    #ifdef DEBUG
	    eva = rcr2();
	    if (type <= MAX_TRAP_MSG) { 
		    uprintf("fatal process exception: %s",
			    trap_msg[type]); 
		    if ((type == T_PAGEFLT) || (type == T_PROTFLT))
			    uprintf(", fault VA = 0x%x", eva);
		    uprintf("\n");  
	    }
    #endif

I think you're only seeing it because you built your kernel with -DDEBUG.
Probably the condition has been happening all along, due to the
VM-synchronized garbage collector that I mentioned in my last message.
But the message hasn't been seen, because most people don't build their
kernels with -DDEBUG.

Perhaps the kernel message should be suppressed, if the process
has a handler installed for the corresponding signal.

John
--
   John Polstra                                       jdp@polstra.com
   John D. Polstra & Co., Inc.                Seattle, Washington USA
   "Self-knowledge is always bad news."                 -- John Barth