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X-CSE-ConnectionGUID: p8FFBmUsQae9vYNLXxd/Mg== X-CSE-MsgGUID: s1+t7PifTkSsEmf2i1ELqg== X-IronPort-AV: E=McAfee;i="6800,10657,11865"; a="97579216" X-IronPort-AV: E=Sophos;i="6.25,204,1779174000"; d="scan'208";a="97579216" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by orvoesa105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Aug 2026 09:49:39 -0700 X-CSE-ConnectionGUID: Ls7GrPklS0iTb+/TBhZ0LQ== X-CSE-MsgGUID: uFtQji7WQkKPFNfDF7+q3g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.25,204,1779174000"; d="scan'208";a="260979901" Received: from jjgreens-desk24.amr.corp.intel.com (HELO [10.125.108.232]) ([10.125.108.232]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 04 Aug 2026 09:49:39 -0700 Message-ID: <64f02f52-434c-4733-8e9b-4dd5daa9e14b@intel.com> Date: Tue, 4 Aug 2026 09:49:36 -0700 Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4] x86/virt/tdx: Formalize SEAMCALL version encoding support To: Xu Yilun , dave.hansen@linux.intel.com, x86@kernel.org, linux-kernel@vger.kernel.org Cc: kas@kernel.org, rick.p.edgecombe@intel.com, yilun.xu@intel.com, linux-coco@lists.linux.dev References: <20260804085054.190847-1-yilun.xu@linux.intel.com> Content-Language: en-US From: Dave Hansen Autocrypt: addr=dave.hansen@intel.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 8/4/26 01:50, Xu Yilun wrote: > SEAMCALL invokes TDX module functions using a function number and Maybe I'm just grumpy this morning, but I'm not a fan of this description. It seems to just be growing complexity and not actually explaining the situation better. Also, this is going to be subtle but it starts talking (I think) about the SEAMCALL _instruction_. The thing this patch should be talking about is SEAMCALLs themselves. The instruction is a _part_ that, sure. But the instruction itself actually has very little to do with the ABI. I just feel like the whole explanation here is going off in a different direction than we need.