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From: Michael Ellerman <mpe@ellerman.id.au>
To: Michael Bringmann <mwb@linux.vnet.ibm.com>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
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        Rashmica Gupta <rashmicy@gmail.com>, Ingo Molnar <mingo@kernel.org>,
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Subject: Re: [PATCH V6 1/2] powerpc/hotplug: Ensure enough nodes avail for operations
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Michael Bringmann <mwb@linux.vnet.ibm.com> writes:

> powerpc/hotplug: On systems like PowerPC which allow 'hot-add' of CPU
> or memory resources, it may occur that the new resources are to be
> inserted into nodes that were not used for these resources at bootup.
> In the kernel, any node that is used must be defined and initialized
> at boot.  In order to meet both needs, this patch adds a new kernel
> command line option (numnodes=<int>) for use by the PowerPC architecture-

Sorry, that's a hack.

I thought you were going to use firmware properties to find the set of
possible nodes. Did that not work?

cheers