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Subject: Re: PATCH: [2.4.21-pre3] Fix for SMP race condition in IDE code
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Ross Biro <rossb@google.com>
Cc: Andre Hedrick <andre@linux-ide.org>,
       Marcelo Tosatti <marcelo@conectiva.com.br>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Fri, 2003-01-10 at 18:12, Ross Biro wrote:
> There is a race condition in all versions of the IDE code that I've 
> looked at including 2.4.18 and 2.4.21-pre3. Basically on an SMP system 
> if mutiple IDE channels are on the same interrupt and 1 channel sends 
> has an interrupt pending on 1 processor while the other processor is 
> calling ide_set_handler, then the interrupt can be mistaken for command 
> completion on both channels, and a command can be completed before it is 
> even issued.

Thanks Ross. I'll go over this in some detail. 
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