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From: Matthew Garrett <mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org>
Subject: Re: MemoryOverwriteRequestControl
Date: Mon, 4 Jul 2016 23:26:09 +0100
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On Mon, Jul 04, 2016 at 02:31:57PM -0700, James Bottomley wrote:

> Currently, the kernel does nothing with this, but you'd more expect
> something in userspace to do something with it, probably a component of
> the TSS.

The OS loader is expected to set MOR to 1, so given the boot stub 
there's need for kernel support. A "correct" implementation would also 
involve the kernel clearing all its secrets before reboot and then 
setting it back to 0, so I don't think we can just punt responsibility 
to userspace.

-- 
Matthew Garrett | mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org