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Re: The impact to change page size to 16k for cache alias

To: 林建安 <colin@realtek.com.tw>
Subject: Re: The impact to change page size to 16k for cache alias
From: Zhang Le <r0bertz@gentoo.org>
Date: Mon, 30 Mar 2009 16:24:15 +0800
Cc: Ralf Baechle <ralf@linux-mips.org>, linux-mips@linux-mips.org
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On 12:06 Mon 30 Mar     , 林建安 wrote:
>
> Hi all,
> We are willing to use 16k page size to avoid cache alias problem.
> The Linux version we use is 2.6.12. If we just upgrade mm system to 
> support 16k page size, what else problems will happen?
> There is already one thing we know that applications of ELF format  
> applications should be transformed to be 16k alignment.
> Another one, we think, highly suspected to be problematic is that many  
> drivers will be ok for 4k page size but fails for 16k.
> That is because 4k page size had been seemed to be natural for a very 
> long long time.
> Any other problem that shall happen for 16k page size?

Linux on Loongson 2E and 2F uses 16k page size to avoid cache alias problem, 
too.
However, I haven't encountered any problem on Linux kernel itself due to 16k 
page
size.

Anyway, I am not 100% familiar with Loongson patches, so I am not sure whether
the page size problem is already been taken care of in the patch. If you are
interested to find out yourself, you can get the whole source here:
http://repo.or.cz/w/linux-2.6/linux-loongson.git

Zhang, Le
http://zhangle.is-a-geek.org

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