From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Machek <pavel@ucw.cz>
Date: Mon, 27 Oct 2003 09:52:59 +0000
Subject: Re: [PATCH 2.4.23-pre8]  Remove broken prefetching in free_one_pgd()
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To: linux-ia64@vger.kernel.org

Hi!

>  > > This code will prefetch from beyond the end of the page table
>  > > being cleared ... which is clearly a bad thing if the page table
>  > > in question is allocated from the last page of memory (or precedes
>  > > a hole on a discontig mem system).
>  > Prefetching random addresses should be safe...
> 
> It isn't on some CPUs.  Early athlons go bang when you prefetch
> past the end of RAM into unmapped memory for eg.

Well, broken HW :-(, but andi's patch should fix up for that.

								Pavel

-- 
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]