From mboxrd@z Thu Jan  1 00:00:00 1970
From: NeilBrown <neilb@suse.de>
Subject: Re: debian software raid1
Date: Wed, 20 Apr 2011 22:40:14 +1000
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To: Asdo <asdo@shiftmail.org>
Cc: Iordan Iordanov <iordan@cdf.toronto.edu>, Mathias =?ISO-8859-1?B?QnVy?= =?ISO-8859-1?B?6W4=?= <mathias.buren@gmail.com>, b2 <b2@playtime.bg>, linux-raid@vger.kernel.org
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On Wed, 20 Apr 2011 12:28:45 +0200 Asdo <asdo@shiftmail.org> wrote:

> On 04/20/11 00:51, NeilBrown wrote:
> > If there was such a deadlock, it would be a serious bug.   I don't believe
> > such a bug exists (but hey - I keep finding bugs in this code, when I'm not
> > busy writing new bugs, so I guess it could crash you machine and kill your
> > cat).
> >
> 
> I am aware that raids 0,1,10 do not copy the buffer so I don't think 
> there is risk of deadlock...
> 
> Raids 456 do copy the buffer... but the destination buffers are 
> preallocated, right?

Correct - destination buffers - when used - are preallocated.

If this were not the case you would get deadlocks in normal usage without
having to wait for suspend/resume to trigger them.

NeilBrown