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Date: Fri, 31 Aug 2018 13:26:39 +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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 Benjamin Herrenschmidt <benh@au1.ibm.com>
Subject: Re: [PATCH 2/2] sched/topology: Expose numa_mask set/clear functions
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On Fri, Aug 31, 2018 at 01:12:53PM +0200, Peter Zijlstra wrote:
> NAK, not until you've fixed every cpu_to_node() user in the kernel to
> deal with that mask changing.

Also, what happens if userspace reads that information; uses libnuma and
then you go and shift the world underneath their feet?

> This is absolutely insane.