From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794323645; b=BUqNdF88DCESxq5woAbzmwTqJFWxRa8EQmQqbI5YVc7LXxDLfDFGWSjXZ2nVqUuhez38 BpxFpHTETyIGrlf0xpkIoMt6hcNczgcJkWlmGlH8UWyVMuf4nn3Kkss7I2O6DftKj1scg rp0rFz8eHyLGvStVZ/sGoBpMFYcWqVvuAUS/yk+KsF5TneoDnReth/Io822oafZoGhY85 d7uRWJ2TukUUwrCfQj9woZzMIQR0ImcL0kRbdTQFJuk9v1iSdRg+p/rlwUllD+/6M4w1F vOUJtvoNmmO4+c5ApHmmCeqI2ptXmXLv8acoPIP8LkNgo5vp87pcs8wT4o6ks6yp+xQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794323645; h=Received:DKIM-Signature:Date:From:To:Cc:Subject:Message-ID: References:MIME-Version:Content-Type:Content-Disposition:In-Reply-To; bh=nZtTE9paxgqbhh5kaB/rcE90qtPhb/tsUpxc9TASPi8=; b=UgWDEqv62fAGdohcPU1Y8pFRc+Z7X8y4B3r+f9BDyzNNcgY4zV0DWIslcTy5X5xMTUOT oi4CoisXwbYLuOhkkRSkkmo83cBdBKG5h33GdiOd+y9A2PAweyFzOEinRE1yBw10Cx5oO Ipz+3rY5Ivw4xGXu07LYXonEX4SoTatYOPddInVtyUmAFMCYOuhHkHNEHsgcOdPY+vuQV n+KWpuEjkDcSseLoKcuyZP0l0YPRHjM8ZgJ7A69pkeqAgx/orjZq36QsSM1x/+ikgf5Kd wWHQvr5iKuG+ljZ1dIhtTYKQygEZrQfFuuFR/vevxfMo5A9D2dkuvnwEIU4HnfL2PPw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b="IS6Z/kA0"; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with UTF8SMTPS id E9B50606A33B; Tue, 10 Nov 2026 15:14:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=IS6Z/kA0 Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id 467171F008A4; Tue, 10 Nov 2026 15:14:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794323644; bh=nZtTE9paxgqbhh5kaB/rcE90qtPhb/tsUpxc9TASPi8=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=IS6Z/kA0idabiGJvH6bkB1y+TyKRGjJTUkNRKx4WHWiABqQHySl93a6jwIyBiFXRl Bhq7Je3CW+t/yjYbnkIDhZpxJaQT/TfUqSBmtXSOT1DXDHjHHgNIEchjeUXhQ0gbqf Ls9vkeHlgbuPrvmTqKUrXU7458UL+rdqMa4IlLUUkaUb1CUpc9vDC0Q2apKV5SIWYB tRoBEAFAupyfYkL5/EIhI/NNxBHFV0vAjzi6Pr7OJPhFVwl9tAcOq32G7cJWG0HLMK oxd01iy5g28/YPrDmNySki9uG1OgiQaT5iwYpPrHqghJ3NIqXxMDUnK2WQ8uuSvBJL oPWluHk8JZdjQ== Date: Tue, 10 Nov 2026 17:14:00 +0200 From: Jarkko Sakkinen To: Jorge Ramirez-Ortiz Cc: peterhuewe@gmx.de, jgg@ziepe.ca, sumit.garg@oss.qualcomm.com, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org Subject: Re: [PATCH v2 1/2] tpm: add OP-TEE transport core and a discrete TPM driver Message-ID: References: <20261110141923.3100770-1-jorge.ramirez@oss.qualcomm.com> <20261110141923.3100770-2-jorge.ramirez@oss.qualcomm.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261110141923.3100770-2-jorge.ramirez@oss.qualcomm.com> On Tue, Nov 10, 2026 at 03:19:08PM +0100, Jorge Ramirez-Ortiz wrote: > Some platforms place a real (discrete) TPM on a bus that only the secure > world can drive. OP-TEE owns that bus, so the normal world cannot reach > the chip directly; it instead exposes a mediator trusted application > that relays TPM2 commands. Add a driver that talks to that application > and presents the chip as a standard TPM2 character device, so the > normal-world TPM stack works unchanged. > > This is a separate driver from the firmware-TPM one rather than a reuse > of it. The TEE transport is the same and is shared through a common > core, but the device identity differs: the firmware TPM uses its own > application and a public-login session, whereas a discrete chip needs > its own application and is restricted to kernel access so that user > space and other applications cannot submit raw commands to it. Folding > both into one driver would also break on a platform that has both. > > Signed-off-by: Jorge Ramirez-Ortiz Looks pretty good. Did you check the Sashiko remark? https://sashiko.dev/#/patchset/20261110141923.3100770-1-jorge.ramirez%40oss.qualcomm.com Br, Jarkko