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To: Nathan Fontenot <nfont@linux.vnet.ibm.com>, linuxppc-dev@lists.ozlabs.org
From: Michael Ellerman <patch-notifications@ellerman.id.au>
Subject: Re: [RESEND,
 V2] powerpc/numa: Invalidate numa_cpu_lookup_table on cpu remove
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Date: Fri,  9 Feb 2018 15:00:33 +1100 (AEDT)
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On Fri, 2018-01-26 at 19:41:59 UTC, Nathan Fontenot wrote:
> When DLPAR removing a CPU, the unmapping of the cpu from a node in
> unmap_cpu_from_node() should also invalidate the CPUs entry in the
> numa_cpu_lookup_table. There is not a guarantee that on a subsequent
> DLPAR add of the CPU the associativity will be the same and thus
> could be in a different node. Invalidating the entry in the
> numa_cpu_lookup_table causes the associativity to be read from the
> device tree at the time of the add.
> 
> The current behavior of not invalidating the CPUs entry in the
> numa_cpu_lookup_table can result in scenarios where the the topology
> layout of CPUs in the partition does not match the device tree
> or the topology reported by the HMC.
> 
> Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
> Reviewed-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/1d9a090783bef19fe8cdec878620d2

cheers