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Subject: Re: Cache aliasing
From: "David S. Miller" <davem@redhat.com>
To: John Newlin <jnewlin@tsoft.com>
Cc: linux-kernel@vger.kernel.org
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Date: 25 Feb 2003 19:59:02 -0800
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On Mon, 2003-02-24 at 23:24, John Newlin wrote:
> Would it make more sense to just always ensure that your 
> virtual and physical pages had matching "color" bits?

No, it's actually very difficult to solve the problem this
way.

The reason being that there is always a fixed "kernel virtual
color" every physical page has.  So essentially, if you colored
userspace, you could only put into user virtual address with
color X only pages that also have kernel virtual color X.