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Subject: Re: [RFC v2 16/32] x86/tdx: Handle MWAIT, MONITOR and WBINVD
To:     Andi Kleen <ak@linux.intel.com>,
        Dan Williams <dan.j.williams@intel.com>
Cc:     Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Tony Luck <tony.luck@intel.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        Raj Ashok <ashok.raj@intel.com>,
        Sean Christopherson <seanjc@google.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Message-ID: <55fd7fbe-4d36-1c1d-532b-bfa876542cd7@intel.com>
Date:   Tue, 11 May 2021 10:42:40 -0700
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On 5/11/21 10:06 AM, Andi Kleen wrote:
>> How do these end up in practice?  Do they still say "general protection
>> fault..."?
> 
> Yes, but there's a #VE specific message before it that prints the exit
> reason.
> 
>> Isn't that really mean for anyone that goes trying to figure out what
>> caused these?  If they see a "general protection fault" from WBINVD and
>> go digging in the SDM for how a #GP can come from WBINVD, won't they be
>> sorely disappointed?
> 
> They'll see both the message and also that it isn't a true #VE in the
> backtrace.

Is there a good reason for the enduring "general protection fault..."
message other than an aversion to refactoring the code?