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Subject: Re: [RFC v2-fix 1/1] x86/traps: Add #VE support for TDX guest
To:     Dave Hansen <dave.hansen@intel.com>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
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Cc:     Tony Luck <tony.luck@intel.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Raj Ashok <ashok.raj@intel.com>,
        Sean Christopherson <seanjc@google.com>,
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        Sean Christopherson <sean.j.christopherson@intel.com>
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From:   Andi Kleen <ak@linux.intel.com>
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Date:   Tue, 18 May 2021 09:00:36 -0700
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> No APIC access either?


It's all X2APIC inside TDX which uses MSRs

>
> Also, shouldn't we have at least a:
>
> 	WARN_ON_ONCE(in_nmi());
>
> if we don't expect (or handle well) #VE in NMIs?

We handle it perfectly fine. It's just not needed.


-Andi