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Date: Thu, 11 Aug 2016 17:44:46 +0800
From: Xishi Qiu <qiuxishi@huawei.com>
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To: Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will.deacon@arm.com>
CC: Linux MM <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>,
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Subject: arm64: why set SECTION_SIZE_BITS to 1G size?
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Hi everyone:
arm64:
SECTION_SIZE_BITS 30 -----1G

The memory hotplug(add_memory -->check_hotplug_memory_range) 
must be aligned with section.So I can not add mem with 64M ...
Can I modify the SECTION_SIZE_BITS to 26?

Thanks,
Xishi Qiu