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Subject: Re: offlining cpus breakage
From: Michael Ellerman <michael@ellerman.id.au>
To: Alexey Kardashevskiy <aik@ozlabs.ru>
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Date: Fri, 16 Jan 2015 14:04:42 +1100
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Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>, "Shreyas
 B. Prabhu" <shreyas@linux.vnet.ibm.com>,
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On Fri, 2015-01-16 at 13:28 +1300, Alexey Kardashevskiy wrote:
> On 01/16/2015 02:22 AM, Preeti U Murthy wrote:
> > Hi Alexey,
> > 
> > Can you let me know if the following patch fixes the issue for you ?
> > It did for us on one of our machines that we were investigating on.
> 
> This fixes the issue for me as well, thanks!
> 
> Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>	

OK, that's great.

But, I really don't think we can ask upstream to merge this patch to generic
code when we don't have a good explanation for why it's necessary. At least I'm
not going to ask anyone to do that :)

So Pretti can you either write a 100% convincing explanation of why this patch
is correct in the general case, or (preferably) do some more investigating to
work out what Alexey's bug actually is.

cheers