Re: [PATCH] powerpc/hotplug-mem: Fix aa_index match bug for hotplug

From: Michael Ellerman
Date: Tue May 30 2017 - 07:43:00 EST


Michael Bringmann <mwb@xxxxxxxxxxxxxxxxxx> writes:

> When adding or removing memory, the aa_index (affinity value) for the
> memblock must also be converted to match the endianness of the rest
> of the 'ibm,dynamic-memory' property. Otherwise, subsequent retrieval
> of the attribute will likely lead to non-existent nodes, followed by
> using the default node in the code inappropriately.
>
> Signed-off-by: Michael Bringmann <mwb@xxxxxxxxxxxxxxxxxx>
>
> diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
> index e104c71..1fb162b 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -124,6 +124,7 @@ static struct property *dlpar_clone_drconf_property(struct device_node *dn)
> for (i = 0; i < num_lmbs; i++) {
> lmbs[i].base_addr = be64_to_cpu(lmbs[i].base_addr);
> lmbs[i].drc_index = be32_to_cpu(lmbs[i].drc_index);
> + lmbs[i].aa_index = be32_to_cpu(lmbs[i].aa_index);
> lmbs[i].flags = be32_to_cpu(lmbs[i].flags);
> }
>

AFAICS this code was added in commit 5f97b2a0d176 ("powerpc/pseries:
Implement memory hotplug add in the kernel").

So this should probably be marked:

Fixes: 5f97b2a0d176 ("powerpc/pseries: Implement memory hotplug add in the kernel")

And it seems like a bug we'd want fixed in stable, so:

Cc: stable@xxxxxxxxxxxxxxx # v4.1+


Am I right?

cheers