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Date: Mon, 19 May 2008 16:35:05 +0300
From: Avi Kivity <avi@qumranet.com>
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To: Ingo Molnar <mingo@elte.hu>
CC: Andrew Morton <akpm@osdl.org>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Make LIST_POISON less deadly
References: <1211125094-32167-1-git-send-email-avi@qumranet.com> <20080519130151.GE13546@elte.hu> <48317E2B.2030304@qumranet.com> <20080519132250.GA20793@elte.hu>
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Ingo Molnar wrote:
> * Avi Kivity <avi@qumranet.com> wrote:
>
>   
>>> i'd suggest to add an ARCH_ILLEGAL_POINTER define instead, which 
>>> defaults to zero and gets added to pointer-ish poison values. That 
>>> makes it both simpler and also it does not need any include/asm 
>>> changes because ARCH_ILLEGAL_POINTER can be set from the Kconfig 
>>> space.
>>>       
>> Right.
>>
>> How much unmapped space do we have on i386 or other archs?  The deltas 
>> added to ARCH_ILLEGAL_POINTER will have to be limited to that.
>>     
>
> can we get away with having the offset default to zero, and all poison 
> values remain unchanged if that? Then 64-bit x86 could just set the 
> offset to 2^63 and we wont have to worry about 32-bit x86 at all ...
>
> i.e. start small with this and only have an effect on 64-bit x86.
>   

Sure, will post an updated patch.

-- 
error compiling committee.c: too many arguments to function