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Date: Fri, 24 Dec 2004 15:32:34 -0800 (PST)
From: Linus Torvalds <torvalds@osdl.org>
To: Andrea Arcangeli <andrea@suse.de>
cc: Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Thomas Gleixner <tglx@linutronix.de>, Andrew Morton <akpm@osdl.org>
Subject: Re: VM fixes [4/4]
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On Fri, 24 Dec 2004, Andrea Arcangeli wrote:
>
>  /*
> + * All archs should support atomic ops with
> + * 1 byte granularity.
> + */
> +	unsigned char memdie;

This simply fundamentally isn't true, last I looked.

At least older alphas do _not_ support atomic byte accesses, and if you
want atomic accesses you need to either use the defined smp-atomic
functions (ie things like the bit set operations), or you need to use 
"int", which afaik all architectures _do_ support atomic accesses to. 

		Linus