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Date: Mon, 29 Jun 2020 14:58:40 +0000 (UTC)
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To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Subject: Re: [PATCH v5 3/3] mm/page_alloc: Keep memoryless cpuless node 0
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On Wed, 24 Jun 2020, Srikar Dronamraju wrote:

> Currently Linux kernel with CONFIG_NUMA on a system with multiple
> possible nodes, marks node 0 as online at boot.  However in practice,
> there are systems which have node 0 as memoryless and cpuless.

Maybe add something to explain why you are not simply mapping the
existing memory to NUMA node 0 which is after all just a numbering scheme
used by the kernel and can be used arbitrarily?

This could be seen more as a bug in the arch code during the setup of NUMA
nodes. The two nodes are created by the firmwware / bootstrap code after
all. Just do not do it?