From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.8]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9C1C018DF9D for ; Wed, 18 Mar 2026 07:13:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.8 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773817998; cv=none; b=K2v9L4Xqv5xX+QMFSM5fnLvfIYwEaeSmNDFehvm5vSJSnREJqWx7TE6k+ot4pjNRb819Te0IhYNZo4f6tiVHgQgWB0eiXV9+lqNJJj0Cwg4DV1QiPPqslejW7w5/Jr77XFDaYCmfj2dbnsNqM8Bc+Lx9IFOFc5P35GI7VOzPMOE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773817998; c=relaxed/simple; bh=ZoFcTiK9dwks0CzY+u+U0zNNzCaL6zIBHQTN8cNkkU0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=Z0c3r+PLDbZCqC3qUAfwfINzAjhEfgU7EO4okeiaC9iDVh9hM0Q6jkbvlVhCfI0Uju/8gqmMW6v8prMCIf+5grVBHTACGHAVUPlARlGCSryTwp9H/XrkGIDp+e+w6Xs0waR4luU5TEn11uR4BhGxbyhqdUpH59kfohYFX/3eM70= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=koSA6Kw6; arc=none smtp.client-ip=192.198.163.8 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="koSA6Kw6" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1773817998; x=1805353998; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=ZoFcTiK9dwks0CzY+u+U0zNNzCaL6zIBHQTN8cNkkU0=; b=koSA6Kw6ch5+MRSys+0zRPi0MRDJBET2ax32XMBeZPOMQjNe5lbQ+ygZ Gtj4jl+o4c94MTVwzX9HoWreczLOQVoCDjjmDg0vpjrmxDZ96pkpOYlST kYSOlyBmHEQXd5CqYJvvLphA9ZOT+Lj71ITpvCdJqSimxY+rBhHYrjshL l4+PVRtm6+TWbBfRFBZCS+YUtKF3R1HhpmzX2lEAafwTfjyedggUvklQc lo6SQvoQmx1MvnJk3nVAxAt0QEg8n96+okDm9vJSvbmdhgMk56fP0Obzr G+/Hs63IdfxNdV/jNaTcdcGYJN42MYYYSGDz5VaDBSD0e0iyLjFAnoWYv w==; X-CSE-ConnectionGUID: CTvb3x2zQiaGLsV1YWMT0g== X-CSE-MsgGUID: 6ZgdssqpTM+b4TFXCN1G7A== X-IronPort-AV: E=McAfee;i="6800,10657,11732"; a="92435948" X-IronPort-AV: E=Sophos;i="6.23,127,1770624000"; d="scan'208";a="92435948" Received: from orviesa008.jf.intel.com ([10.64.159.148]) by fmvoesa102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Mar 2026 00:13:17 -0700 X-CSE-ConnectionGUID: rP5REFf2RtaKNdJ5X9SOuA== X-CSE-MsgGUID: fhp9d5bJSMmkPUv87y9hHQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,127,1770624000"; d="scan'208";a="222581920" Received: from unknown (HELO [10.239.158.72]) ([10.239.158.72]) by orviesa008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Mar 2026 00:13:09 -0700 Message-ID: <935081ba-9f66-4bdf-a408-c19be32c6ad3@intel.com> Date: Wed, 18 Mar 2026 15:13:06 +0800 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 v5 04/22] x86/virt/seamldr: Introduce a wrapper for P-SEAMLDR SEAMCALLs To: Chao Gao , linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org Cc: binbin.wu@linux.intel.com, dan.j.williams@intel.com, dave.hansen@linux.intel.com, ira.weiny@intel.com, kai.huang@intel.com, kas@kernel.org, nik.borisov@suse.com, paulmck@kernel.org, pbonzini@redhat.com, reinette.chatre@intel.com, rick.p.edgecombe@intel.com, sagis@google.com, seanjc@google.com, tony.lindgren@linux.intel.com, vannapurve@google.com, vishal.l.verma@intel.com, yilun.xu@linux.intel.com, Farrah Chen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H. Peter Anvin" References: <20260315135920.354657-1-chao.gao@intel.com> <20260315135920.354657-5-chao.gao@intel.com> Content-Language: en-US From: Xiaoyao Li In-Reply-To: <20260315135920.354657-5-chao.gao@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 3/15/2026 9:58 PM, Chao Gao wrote: > The TDX architecture uses the "SEAMCALL" instruction to communicate with > SEAM mode software. Right now, the only SEAM mode software that the kernel > communicates with is the TDX module. But, there is actually another > component that runs in SEAM mode but it is separate from the TDX module: > the persistent SEAM loader or "P-SEAMLDR". Right now, the only component > that communicates with it is the BIOS which loads the TDX module itself at > boot. But, to support updating the TDX module, the kernel now needs to be > able to talk to it. > > P-SEAMLDR SEAMCALLs differ from TDX module SEAMCALLs in areas such as > concurrency requirements. Add a P-SEAMLDR wrapper to handle these > differences and prepare for implementing concrete functions. > > Note that unlike P-SEAMLDR, there is also a non-persistent SEAM loader > ("NP-SEAMLDR"). This is an authenticated code module (ACM) that is not > callable at runtime. Only BIOS launches it to load P-SEAMLDR at boot; > the kernel does not need to interact with it for runtime update. > > For details of P-SEAMLDR SEAMCALLs, see Intel® Trust Domain CPU > Architectural Extensions, Revision 343754-002, Chapter 2.3 "INSTRUCTION > SET REFERENCE". SDM started to contain SEAMCALL definitions. How about just dropping this paragraph to avoid people from reading the old doc? ... > +static __maybe_unused int seamldr_call(u64 fn, struct tdx_module_args *args) > +{ > + guard(raw_spinlock)(&seamldr_lock); > + return seamcall_prerr(fn, args); How about adding the reason of why choosing seamcall_prerr() instead of seamcall_prerr_ret() in the changelog?