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To: Jeremie Le Hen <jeremie@le-hen.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Mon, 24 Jan 2005 14:45:46 +0100."
             <20050124134546.GB59685@obiwan.tataz.chchile.org> 
Date: Tue, 25 Jan 2005 10:37:06 +0100
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Subject: Re: cvs commit: src/sys/dev/md md.c 
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In message <20050124134546.GB59685@obiwan.tataz.chchile.org>, Jeremie Le Hen writes:

>While talking about WITNESS, I checked my kernel config and remembered
>that FULL_PREEMPTION is on.  The panic disappeared when I turned off
>the latter : I managed to create up to about 16 md(4) devices.  I know
>this should not be enabled for users, but I'm interested in "exposing
>race conditions" as said in the comment.

Well, you clearly did :-)

I suggest you send a summary of what you have found to jhb@freebsd.org,
he's working on the FULL_PREEMPTION stuff.

-- 
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.