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Subject: Re: [PATCH v5 06/12] x86/tdx: Get TD execution environment
 information via TDINFO
To:     Andi Kleen <ak@linux.intel.com>, Borislav Petkov <bp@alien8.de>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
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        Dave Hansen <dave.hansen@intel.com>,
        Tony Luck <tony.luck@intel.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Kirill Shutemov <kirill.shutemov@linux.intel.com>,
        Sean Christopherson <seanjc@google.com>,
        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
        x86@kernel.org, linux-kernel@vger.kernel.org
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From:   "Kuppuswamy, Sathyanarayanan" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
Message-ID: <428c09d3-f636-2a99-e394-e46b57c38b29@linux.intel.com>
Date:   Fri, 20 Aug 2021 12:01:04 -0700
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On 8/20/21 11:58 AM, Andi Kleen wrote:
> 
> 
> Without working TDCALLs the error message won't appear anywhere. The only practical way to debug 
> such a problem is a kernel debugger.
> 
> Also printing an error message might end up recursing because the console write would trigger TDCALL 
> again, or eventually stop because the console lock is already taken. In any case it won't work.

Yes, good point. In this case, adding debug print will not work. But I
can add more comments to the code.

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer