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Subject: Re: [PATCH v5 06/16] x86/tdx: Make DMA pages shared
To:     Tom Lendacky <thomas.lendacky@amd.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
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        Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
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Cc:     Peter H Anvin <hpa@zytor.com>, Dave Hansen <dave.hansen@intel.com>,
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        Kuppuswamy Sathyanarayanan <knsathya@kernel.org>,
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From:   Sathyanarayanan Kuppuswamy 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
Message-ID: <930ec8e0-669d-8501-af66-38e4cab60a1f@linux.intel.com>
Date:   Wed, 20 Oct 2021 10:26:29 -0700
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On 10/20/21 10:22 AM, Tom Lendacky wrote:
>>
>> For non TDX case, in CC_ATTR_HOST_MEM_ENCRYPT, we should still call
>> amd_force_dma_unencrypted() right?
> 
> What I'm saying is that you wouldn't have amd_force_dma_unencrypted(). I 
> think the whole force_dma_unencrypted() can exist as-is in a different 
> file, whether that's cc_platform.c or mem_encrypt_common.c.
> 
> It will return true for an SEV or TDX guest, true for an SME host based 
> on the DMA mask or else false. That should work just fine for TDX.

Got it. Thanks for clarifying it.

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer