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To: Poul-Henning Kamp <phk@critter.dk.tfs.com>
cc: Luigi Rizzo <luigi@labinfo.iet.unipi.it>, swallace@ece.uci.edu,
        current@FreeBSD.ORG
Subject: Re: exec bug 
In-reply-to: Your message of "Sun, 26 Jan 1997 17:48:48 +0100."
             <7583.854297328@critter.dk.tfs.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Sun, 26 Jan 1997 13:32:18 -0800
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>In message <199701261336.FAA06928@root.com>, David Greenman writes:
>
>>   ...and just how do you tell the exec code that a page fault that occured
>>while it was accessing the image header was "fatal"? The only mechanism we
>>have for this is signals, and that doesn't work when you're executing in the
>>kernel like this.
>
>Wouldn't it make sense for the image activator to do a couple of probes
>first to see that the data is actually available ?  that way it could
>fail intelligently ?

   The problem is that determining page residency might be too high of an
overhead, but maybe not. See my last reply to Bruce.

-DG

David Greenman
Core-team/Principal Architect, The FreeBSD Project