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Date: Fri, 31 Aug 2018 14:06:36 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
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 linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
 Andre Wild <wild@linux.vnet.ibm.com>,
 Benjamin Herrenschmidt <benh@au1.ibm.com>
Subject: Re: [PATCH] sched/topology: Use Identity node only if required
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On Fri, Aug 31, 2018 at 04:56:18PM +0530, Srikar Dronamraju wrote:
> This was the same in my previous posting too. Before the topology update
> happened, all the cpus would be in SMT, DIE. The topology updates can be
> disabled using a kernel parameter topology_updates=off. Its documented under
> https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html as
> 
>       topology_updates= [KNL, PPC, NUMA] Format: {off} Specify if the kernel
>       should ignore (off) topology updates sent by the hypervisor to this
>       LPAR.
> 
> and is not something new in powerpc.

Doesn't mean it isn't utterly broken.