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Date: Wed, 9 Jan 2013 14:49:05 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Tang Chen <tangchen@cn.fujitsu.com>
Subject: Re: [PATCH v6 04/15] memory-hotplug: remove /sys/firmware/memmap/X
 sysfs
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On Wed, 9 Jan 2013 17:32:28 +0800
Tang Chen <tangchen@cn.fujitsu.com> wrote:

> When (hot)adding memory into system, /sys/firmware/memmap/X/{end, start, type}
> sysfs files are created. But there is no code to remove these files. The patch
> implements the function to remove them.
> 
> Note: The code does not free firmware_map_entry which is allocated by bootmem.
>       So the patch makes memory leak. But I think the memory leak size is
>       very samll. And it does not affect the system.

Well that's bad.  Can we remember the address of that memory and then
reuse the storage if/when the memory is re-added?  That at least puts an upper
bound on the leak.