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Re: [Xen-devel] [patch] (resend) mask out nx bits when calculatingpfn/mf

To: "Nakajima, Jun" <jun.nakajima@xxxxxxxxx>
Subject: Re: [Xen-devel] [patch] (resend) mask out nx bits when calculatingpfn/mfn
From: "Scott Parish" <srparish@xxxxxxxxxx>
Date: Tue, 7 Jun 2005 16:23:10 +0000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx, Scott Parish <srparish@xxxxxxxxxx>
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On Tue, Jun 07, 2005 at 09:58:20AM -0700, Nakajima, Jun wrote:

> But did you really see the NX bit? I think that (NX bit) would be a good
> catch and it explains several failures of device drivers.  We should fix
> the creator of the pte (by __supported_pte_mask), not the consumer of
> it.

I was seeing it in xen_contig_memory(), which was getting called by
e100_alloc_cbs(). The crash was happening when i would run "xend start"

By "fix the creator", your suggesting that there shouldn't be an NX bit
set? Why?

> We also need to fix Xen because Xen should not reject the request just
> because it has the NX bit on.

An NX bit is now an official part of a page frame number???

i'm confused


Scott Parish
Signed-off-by: srparish@xxxxxxxxxx

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