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Date:   Fri, 24 Jun 2022 09:22:03 -0700
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Subject: Re: [PATCHv7 14/14] x86/tdx: Add unaccepted memory support
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To:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Borislav Petkov <bp@alien8.de>,
        Andy Lutomirski <luto@kernel.org>,
        Sean Christopherson <seanjc@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Joerg Roedel <jroedel@suse.de>,
        Ard Biesheuvel <ardb@kernel.org>
Cc:     Andi Kleen <ak@linux.intel.com>,
        Kuppuswamy Sathyanarayanan 
        <sathyanarayanan.kuppuswamy@linux.intel.com>,
        David Rientjes <rientjes@google.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Peter Zijlstra <peterz@infradead.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Ingo Molnar <mingo@redhat.com>,
        Varad Gautam <varad.gautam@suse.com>,
        Dario Faggioli <dfaggioli@suse.com>,
        Mike Rapoport <rppt@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        marcelo.cerri@canonical.com, tim.gardner@canonical.com,
        khalid.elmously@canonical.com, philip.cox@canonical.com,
        x86@kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev,
        linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220614120231.48165-1-kirill.shutemov@linux.intel.com>
 <20220614120231.48165-15-kirill.shutemov@linux.intel.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20220614120231.48165-15-kirill.shutemov@linux.intel.com>
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On 6/14/22 05:02, Kirill A. Shutemov wrote:
>  static inline void __accept_memory(phys_addr_t start, phys_addr_t end)
>  {
>  	/* Platform-specific memory-acceptance call goes here */
> -	error("Cannot accept memory");
> +	if (is_tdx_guest())
> +		tdx_accept_memory(start, end);
> +	else
> +		error("Cannot accept memory: unknown platform\n");
>  }

There are quite a few of these

	if (tdx())
		...

conditions in common code here.  Shouldn't this be something like a
CC_ATTR_MEM_ACCEPT?

	if (cc_platform_has(CC_ATTR_MEM_ACCEPT))
		cc_accept_memory(...);
	else
		error("Cannot accept memory: unknown platform\n");

I understand that TDX is the first one to the party.  Is this the time
to add the cc_ infrastructure?