From owner-freebsd-current  Wed Dec 24 23:52:58 1997
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To: Julian Elischer <julian@whistle.com>
cc: Gary Palmer <gjp@erols.com>, current@freebsd.org
Subject: Re: crash (in networking code?) 
In-reply-to: Your message of "Wed, 24 Dec 1997 23:44:54 PST."
             <Pine.BSF.3.95.971224234205.17456E-100000@current1.whistle.com> 
From: David Greenman <dg@root.com>
Reply-To: dg@root.com
Date: Wed, 24 Dec 1997 23:54:07 -0800
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>>    The problem might be fixed with the attached diff. I have also committed
>> this in rev 1.37 of in_pcb.c.
>> 
>> -DG
>Is the aim of this change, to move the MALLOC out of the splnet()
>region?

   No. The purpose is to do the potentially blocking malloc first.

>I would have thought this was safe.  What is the failure mode? (I am not
>saying it's not a problem, just that I don't understand it..) 

   The cached PCB pointer (inp) becomes stale if malloc blocks.

-DG

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