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Date: Wed, 9 Apr 2008 12:08:12 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Davide Libenzi <davidel@xmailserver.org>
Cc: linux-kernel@vger.kernel.org, zach.brown@oracle.com,
       jroberson@chesapeake.net
Subject: Re: [patch] eventfd/kaio integration fix
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On Wed, 9 Apr 2008 11:45:47 -0700 (PDT)
Davide Libenzi <davidel@xmailserver.org> wrote:

> Jeff Roberson discovered a race when using kaio eventfd based 
> notifications. This patch fixes the race by moving the notification inside 
> the spinlocked section of kaio.

Missing information.

What are the consequences of this race, when it occurs?

> The operation is safe since eventfd 
> spinlock and kaio one are unrelated.

Yes, it's safe from that perspective.

However with this patch applied, we will no longer run eventfd_signal() if
kiocbIsCancelled(iocb).  Convincing is needed, please?