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Date: Mon, 30 Jul 2012 12:23:05 +0200
From: Heiko Carstens <heiko.carstens@de.ibm.com>
To: Wen Congyang <wency@cn.fujitsu.com>
Subject: Re: [RFC PATCH v5 12/19] memory-hotplug: introduce new function
 arch_remove_memory()
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Cc: linux-s390@vger.kernel.org, linux-ia64@vger.kernel.org,
 linux-acpi@vger.kernel.org, len.brown@intel.com, linux-sh@vger.kernel.org,
 linux-kernel@vger.kernel.org, cmetcalf@tilera.com, linux-mm@kvack.org,
 Yasuaki ISIMATU <isimatu.yasuaki@jp.fujitsu.com>, paulus@samba.org,
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On Fri, Jul 27, 2012 at 06:32:15PM +0800, Wen Congyang wrote:
> We don't call __add_pages() directly in the function add_memory()
> because some other architecture related things need to be done
> before or after calling __add_pages(). So we should introduce
> a new function arch_remove_memory() to revert the things
> done in arch_add_memory().
> 
> Note: the function for s390 is not implemented(I don't know how to
> implement it for s390).

There is no hardware or firmware interface which could trigger a
hot memory remove on s390. So there is nothing that needs to be
implemented.