From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: early_cpu_init() and identify_cpu()
Date: Tue, 17 Jul 2007 11:23:27 +0100
Message-ID: <C2C2572F.12905%keir@xensource.com>
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On 17/7/07 11:15, "Keir Fraser" <keir@xensource.com> wrote:

> If we just mapped the 4kB-rounded region specified by lfb_base to
> lfb_base+lfb_size (as determined via the VBE Get Mode Info call) as WC,
> would that be safe?

Actually this is probably okay because any software that does want to access
command queues (e.g., X server) will have its own mapping that will not
specify PAT.WC. In contrast MTRR type specification is used by all mappings
of that physical address range. So long as aliasing of WC and UC was not a
problem, this would work fine. But I think it's WC aliasing with WB/WT that
is a problem.

 -- Keir