Re: arm64: why set SECTION_SIZE_BITS to 1G size?

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From	Catalin Marinas <catalin.marinas@arm.com>
Newsgroups	linux.kernel
Subject	Re: arm64: why set SECTION_SIZE_BITS to 1G size?
Date	Thu, 11 Aug 2016 12:10:03 +0200
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On Thu, Aug 11, 2016 at 05:44:46PM +0800, Xishi Qiu wrote:
> 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?

There was a patch to reduce this to 27:

http://lkml.kernel.org/g/1465821119-3384-1-git-send-email-jszhang@marvell.com

Also some discussions in this thread on a different patch:

http://lkml.iu.edu/hypermail/linux/kernel/1604.1/03036.html

Does your system really have such small alignment memory blocks?

-- 
Catalin

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arm64: why set SECTION_SIZE_BITS to 1G size? Xishi Qiu <qiuxishi@huawei.com> - 2016-08-11 11:50 +0200
  Re: arm64: why set SECTION_SIZE_BITS to 1G size? Catalin Marinas <catalin.marinas@arm.com> - 2016-08-11 12:10 +0200

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