From mboxrd@z Thu Jan  1 00:00:00 1970
From: Neil Brown <neilb@suse.de>
Subject: Re: [PATCH] md linear: Protecting mddev with rcu locks to avoid races in
Date: Wed, 17 Jun 2009 20:01:17 +1000
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In-Reply-To: message from Sujit Karataparambil on Wednesday June 17
Sender: linux-raid-owner@vger.kernel.org
To: Sujit Karataparambil <sjt.kar@gmail.com>
Cc: SandeepKsinha <sandeepksinha@gmail.com>, Linux RAID <linux-raid@vger.kernel.org>
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On Wednesday June 17, sjt.kar@gmail.com wrote:
> Sorry what your patch claims is that the raid array can change the number of
> array's otherwise there is no need for an rcu.
> 
> > What makes you think that md is static when you array itself can grow.
> > md contains information pertaining to the array it holds.
> 
> This is what I saying my the md is built statically on top of the raid.

md/linear allows an array to grow while it is only.  You can add a
drive to a 'linear' array and it will become larger to include that
drive.  So the array is not completely static.

NeilBrown