Hi Andrew,

On Thu, Nov 24, 2016 at 06:57:17PM +0900, AKASHI Takahiro wrote:

Add memblock_cap_memory_range() which will remove all the memblock regions
except the memory range specified in the arguments. In addition, rework is
done on memblock_mem_limit_remove_map() to re-implement it using
memblock_cap_memory_range().

This function, like memblock_mem_limit_remove_map(), will not remove
memblocks with MEMMAP_NOMAP attribute as they may be mapped and accessed
later as "device memory."
See the commit a571d4eb55d8 ("mm/memblock.c: add new infrastructure to
address the mem limit issue").

This function is used, in a succeeding patch in the series of arm64 kdump
suuport, to limit the range of usable memory, or System RAM, on crash dump
kernel.
(Please note that "mem=" parameter is of little use for this purpose.)

Signed-off-by: AKASHI Takahiro <redacted>
Reviewed-by: Will Deacon <redacted>
Cc: linux-mm at kvack.org
Cc: Andrew Morton <akpm@linux-foundation.org>
---
 include/linux/memblock.h |  1 +
 mm/memblock.c            | 44 +++++++++++++++++++++++++++++---------------
 2 files changed, 30 insertions(+), 15 deletions(-)

Are you OK with this patch to go in via the arm64 tree (together with
the other patches in this series)?

Thanks.

-- 
Catalin