From: Jiri Slaby <jirislaby@gmail.com>
Subject: Re: [RFC 1/1] mm: add virt to phys debug
Date: Tue, 06 May 2008 23:54:38 +0200
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References: <Pine.LNX.4.64.0804281322510.31163@schroedinger.engr.sgi.com> <1209669740-10493-1-git-send-email-jirislaby@gmail.com> <Pine.LNX.4.64.0805011310390.9288@schroedinger.engr.sgi.com>
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Cc: linux-mm@kvack.org, Ingo Molnar <mingo@elte.hu>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Jeremy Fitzhardinge <jeremy@goop.org>, pageexec@freemail.hu,
	Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
	herbert@gondor.apana.org.au, penberg@cs.helsinki.fi,
	akpm@linux-foundation.org, linux-ext4@vger.kernel.org,
	paulmck@linux.vnet.ibm.com, rjw@sisk.pl, zdenek.kabelac@gmail.com,
	David Miller <davem@davemloft.net>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	linux-kernel@vger.kernel.org, Andi Kleen <andi@firstfloor.org>
To: Christoph Lameter <clameter@sgi.com>
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On 05/01/2008 10:18 PM, Christoph Lameter wrote:
> On Thu, 1 May 2008, Jiri Slaby wrote:
>> Add some (configurable) expensive sanity checking to catch wrong address
>> translations on x86.
>>
>> - create linux/mmdebug.h file to be able include this file in
>>   asm headers to not get unsolvable loops in header files
>> - __phys_addr on x86_32 became a function in ioremap.c since
>>   PAGE_OFFSET and is_vmalloc_addr is undefined if declared in
>>   page_32.h (again circular dependencies)
>> - add __phys_addr_const for initializing doublefault_tss.__cr3
> 
> Hmmm.. We could use include/linux/bounds.h to make 
> VMALLOC_START/VMALLOC_END (or whatever you need for checking the memory 
> boundaries) a cpp constant which may allow the use in page_32.h without 
> circular dependencies.

I like the idea, I'll get back with a patch in few days (sorry, too busy). 
Anyway bounds.h should be include/asm/ thing though.