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Date:   Fri, 18 Mar 2022 16:03:13 +0300
From:   "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Dave Hansen <dave.hansen@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>, mingo@redhat.com,
        bp@alien8.de, luto@kernel.org,
        sathyanarayanan.kuppuswamy@linux.intel.com, aarcange@redhat.com,
        ak@linux.intel.com, dan.j.williams@intel.com, david@redhat.com,
        hpa@zytor.com, jgross@suse.com, jmattson@google.com,
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        thomas.lendacky@amd.com, brijesh.singh@amd.com, x86@kernel.org,
        linux-kernel@vger.kernel.org,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>
Subject: Re: [PATCHv6 07/30] x86/traps: Add #VE support for TDX guest
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On Fri, Mar 18, 2022 at 11:55:11AM +0100, Peter Zijlstra wrote:
> On Thu, Mar 17, 2022 at 01:32:07PM -0700, Dave Hansen wrote:
> 
> > The TDX rules are *much* nicer than SEV.  They're also a lot nicer on
> > TDX _now_ than they used to be.  There are a few stubborn people at
> > Intel who managed to add some drops of sanity to the architecture.
> 
> Right; that is saner than it used to be. I have definite memories that
> pages could be taken back by the TDX thing and would need
> re-authentication. A pool of 'fixed' pages was talked about. I'm glad to
> hear all that is gone.

Right, VMM can still pull memory form the guest at any point, but
reference of such memory from the guest would lead not to #VE as before,
but to TD termination.

-- 
 Kirill A. Shutemov