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Date: Fri, 02 Feb 2024 00:02:42 +0200
Message-Id: <CYU2YB3KWV7V.1NHLFEN71HC3N@suppilovahvero>
Cc: "Kuppuswamy Sathyanarayanan"
 <sathyanarayanan.kuppuswamy@linux.intel.com>, "Qinkun Bao"
 <qinkun@google.com>, "Yao, Jiewen" <jiewen.yao@intel.com>, "Xing, Cedric"
 <cedric.xing@intel.com>, "Dionna Amalie Glaze" <dionnaglaze@google.com>,
 <biao.lu@intel.com>, <linux-coco@lists.linux.dev>,
 <linux-integrity@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [RFC PATCH v2 0/4] tsm: Runtime measurement registers ABI
From: "Jarkko Sakkinen" <jarkko@kernel.org>
To: "Samuel Ortiz" <sameo@rivosinc.com>, "Dan Williams"
 <dan.j.williams@intel.com>
References: <20240128212532.2754325-1-sameo@rivosinc.com>
In-Reply-To: <20240128212532.2754325-1-sameo@rivosinc.com>

On Sun Jan 28, 2024 at 11:25 PM EET, Samuel Ortiz wrote:
> Some confidential computing architectures (Intel TDX, ARM CCA, RISC-V
> CoVE) provide their guests with a set of measurements registers that can
> be extended at runtime, i.e. after the initial, host-initiated
> measurements of the TVM are finalized. Those runtime measurement
> registers (RTMR) are isolated from the host accessible ones but TSMs
> include them in their signed attestation reports.

Please expand "TSM" acronym and explain what it is.

> All architectures supporting RTMRs expose a similar interface to their

Please expand RTMR *everywhere* ot "measurement registers". It is
totally useless terminology.

> TVMs: An extension command/call that takes a measurement value and an

What is TVM?

> RTMR index to extend it with, and a readback command for reading an RTMR
> value back (taking an RTMR index as an argument as well). This patch seri=
es
> builds an architecture agnostic, configfs-based ABI for userspace to exte=
nd
> and read RTMR values back. It extends the current TSM ops structure and
> each confidential computing architecture can implement this extension to
> provide RTMR support.

This patch set should simplify its gibberish terminology to common
language.

BR, Jarkko