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Date: Wed, 11 Aug 2004 18:30:29 -0400 (EDT)
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
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To: Andre Oppermann <andre@FreeBSD.ORG>
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Subject: Re: cvs commit: src/sys/netinet ip_divert.c raw_ip.ctcp_hostcache.c 
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<<On Wed, 11 Aug 2004 20:09:24 +0200, Andre Oppermann <andre@FreeBSD.ORG> said:

> In all cases the zone is used as kmalloc replacement.  It always
> initializes a newly allocated object.  It always unlinks the object
> from any lists before it uma_zfree's it.  All such operations are
> covered by mutexes, no concurrent access should happen.  If there
> is any use-after-free then it is a bug that needs to be fixed.

No, it is an intentional design choice, not a bug.  Lock-free
synchronization is good, particularly when you're copying out a giant
wodge of PCBs to userland (or doing anything else that might take a
really long time).  Locks should not be held during this process.

-GAWollman