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Date:   Tue, 12 Oct 2021 16:59:51 -0400
From:   "Michael S. Tsirkin" <mst@redhat.com>
To:     Andi Kleen <ak@linux.intel.com>
Cc:     Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Richard Henderson <rth@twiddle.net>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
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Subject: Re: [PATCH v5 16/16] x86/tdx: Add cmdline option to force use of
 ioremap_host_shared
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On Tue, Oct 12, 2021 at 10:55:20AM -0700, Andi Kleen wrote:
> 
> > I mean ... it's already wide spread.
> 
> 
> I meant wide spread usage with confidential guests.
> 
> > If we support it with TDX
> > it will be used with TDX.
> 
> It has some security trade offs. The main reason to use TDX is security.
> Also when people take the VT-d tradeoffs they might be ok with the BIOS
> trade offs too.
> 
> -Andi

Interesting. VT-d tradeoffs ... what are they?
Allowing hypervisor to write into BIOS looks like it will
trivially lead to code execution, won't it?

-- 
MST