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Subject: Re: [RFC v2 27/32] x86/tdx: Exclude Shared bit from __PHYSICAL_MASK
From:   "Kuppuswamy, Sathyanarayanan" 
        <sathyanarayanan.kuppuswamy@linux.intel.com>
To:     Dave Hansen <dave.hansen@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Tony Luck <tony.luck@intel.com>
Cc:     Andi Kleen <ak@linux.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@vger.kernel.org
References: <cover.1619458733.git.sathyanarayanan.kuppuswamy@linux.intel.com>
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 <3ae38a0b-0676-1543-7015-39a589b2807a@intel.com>
 <0df80c0f-e0da-e86e-0ab8-abc58f0da559@linux.intel.com>
Message-ID: <e1502131-ec8b-df1e-cb94-9285799f7e79@linux.intel.com>
Date:   Thu, 20 May 2021 11:56:53 -0700
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On 5/20/21 11:48 AM, Kuppuswamy, Sathyanarayanan wrote:
> BTW, do you find it confusing that the subject says: '__PHYSICAL_MASK'
> and yet the code only modifies 'physical_mask'?

"physical_mask" is defined as __PHYSICAL_MASK in page_types.h. MM code seems to
use __PHYSICAL_MASK for common usage. But for our use case, if it makes it more
readable, I am fine with using "physical_mask".

arch/x86/include/asm/page_types.h:57:#define __PHYSICAL_MASK		physical_mask
arch/x86/mm/pat/memtype.c:560:		return address & __PHYSICAL_MASK;

-- 
Sathyanarayanan Kuppuswamy
Linux Kernel Developer