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To: "M. Warner Losh" <imp@bsdimp.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 23 Aug 2008 10:01:55 CST."
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Date: Sat, 23 Aug 2008 17:15:38 +0000
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Cc: freebsd-usb@freebsd.org
Subject: Re: usb4bsd patch review 
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In message <20080823.100155.1310242209.imp@bsdimp.com>, "M. Warner Losh" writes
:

>While this may be a good idea, I'm hesitant about races that it may
>introduce.  This is the classic point of attack: do something between
>steps of a formerly atomic operation that was made non-atomic.  I
>can't think of anything off the top of my head, but I'm still
>concerned.

We have ways of closing the race if need be, but they're all slightly
kludgy, but I am not overly concerned about those races as long as
the default is to not give access.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.