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Re: [PATCH] cleanup hardcoding __pa/__va macros etc. (take-2)

To: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Subject: Re: [PATCH] cleanup hardcoding __pa/__va macros etc. (take-2)
From: girish <girishvg@gmail.com>
Date: Wed, 27 Sep 2006 00:20:30 +0900
Cc: "linux-mips@linux-mips.org" <linux-mips@linux-mips.org>, girish <girishvg@gmail.com>
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Thread-topic: [PATCH] cleanup hardcoding __pa/__va macros etc. (take-2)
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>> The idea is to differentiate the Kseg0/Kseg1 segments in the physical area.
>> Beyond these areas lies the mapped area (or the HIGHMEM). What complicates
>> this matter further is their overlapping nature. The __pa()/__va() treated
>> all addresses mapped into PAGE_OFFSET (8000_0000) area. The effort is to
>> correctly differentiate these areas.
> 
> Yes, __va() and __pa() are used to convert an physical address from/to
> an kernel logical address (i.e. low unmapped virtual address).
> 
> I think passing another sort of addresses to them is simply wrong.

Agreed. 

But, then again treating all addresses as above PAGE_OFFSET is also wrong :)
I looked at it just as a work around. These macros are called from so many
other places that if an access is made at say 4000_0000 the kernel will oops
telling it was C000_0000 access error. Now that confused me a lot! With this
change now kernel oops on 4000_0000 :)

Anyway, you may ignore __pa/__va macros.

Could you please look into other changes I proposed?


> 
> P.S.
> Please do not reply to git-commits@linux-mips.org.

I am sorry. It was a stupid mistake in creating address book entry.



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