From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 49A682874FE for ; Fri, 13 Feb 2026 15:49:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770997748; cv=none; b=ONs6KgflN+tSNwaGwAwm+z0HY/MC6fOnsw1OgNsqd3ov6608fg/5YHEar6oFWlmNay3oTtURaA+++4pI3P9CCD6EirP93ERChXzTxka8hs4Ovo8UmpVd6Z2Jzjro4mFduDQvBA9wTscqmmU/+um97Df/fHA7u+Flj/AoEdDRqjY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770997748; c=relaxed/simple; bh=i7MuEqAdhQv5L7osd2aY7wSxtwL2T3OlBMSxan8ngHo=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=qYrCSNwX8di0aS0GRr9Sm3/HLb7+N1DnNj+Fz9aGqU+GHZYXaETisS2bfpqwggajCwZfbFoaCBGVhctx4gWO6NFLfj7yrGhZY9/gCebIT2gCl5EWePxlhvKVu3196D0Ou4Ot57HMtDPhWlf3Uzc2H0GZtwkAIYio+9hs4iHsVsA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RGAP4wtX; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="RGAP4wtX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AA69EC116C6; Fri, 13 Feb 2026 15:49:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770997748; bh=i7MuEqAdhQv5L7osd2aY7wSxtwL2T3OlBMSxan8ngHo=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=RGAP4wtXguFmIFW5blb/q93YgqwFxX0dLcyZ/UwimY2GrYlc0qrsyt3psiMXXEp/Z 8AUgcS6lBxgWBVXe8dPcTf5HioOuUy7OMBNChH7ostXIRnqQHpmUPpqiBFtQD/Th6T ldz2KzQcPF3/3HL5RKp8JW7oYL3pcYweX0vlc1BDH96eJCwiGPCP7qT3HX9msuAtJw QZ6LmyY3P5/dn7vG7j24E4UgK0hsQo/aFmktOurfgk6FmmfO4wginG+ashj34rZqQU EHHnRzSxRaxYr8futJt2H3GkrOcANe8IAB7zDYljSTjuvvhtmxQeTDIoVZ/ze9knTE s3+neVJUHttiQ== Message-ID: Date: Fri, 13 Feb 2026 16:49:03 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] arm64: defconfig: tpm : Enable fTPM TEE support To: Andrew Davis , Atharv Dubey , Krzysztof Kozlowski , Geert Uytterhoeven , Bjorn Andersson , Arnd Bergmann Cc: Heiko Stuebner , Eric Biggers , Luca Weiss , =?UTF-8?Q?N=C3=ADcolas_F_=2E_R_=2E_A_=2E_Prado?= , Lad Prabhakar , Kuninori Morimoto , linux-kernel@vger.kernel.org, m-chawdhry@ti.com, vigneshr@ti.com, u-kumar1@ti.com, nm@ti.com References: <20260211061540.448475-1-a-dubey@ti.com> <66aa0f19-9ece-4ea1-8f06-dd4436719678@ti.com> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 13/02/2026 16:26, Andrew Davis wrote: > On 2/11/26 12:22 AM, Krzysztof Kozlowski wrote: >> On 11/02/2026 07:15, Atharv Dubey wrote: >>> Enable CONFIG_TCG_FTPM_TEE as a module for all >>> the platforms to support firmware-based TPM >>> through OP-TEE. >> >> What all platforms? Again, this is not your distro defconfig. Explain >> why do we want it in upstream. >> > > "All" seems correct here, the fTPM TA is usable by any ARM64 platform > with OP-TEE support, which looks to be just about everyone[0]. > > Why do we want it upstream?: to support firmware-based TPM > through OP-TEE. > > What more are you looking for, how do we prove some feature that was > deemed useful enough to include in the kernel is useful enough to enable? Most of other commits also claimed similar, so I want to be sure that this one is real "all". Probably this should build on top of existing OPTEE support. > >> Please wrap commit message according to Linux coding style / submission >> process (neither too early nor over the limit): >> https://elixir.bootlin.com/linux/v6.4-rc1/source/Documentation/process/submitting-patches.rst#L597 >> >>> >>> Bloat-o-meter Statistics : >>> add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0 (0) >>> Function old new delta >>> Total: Before=32968311, After=32968311, chg +0.00% >> >> Really? You put here a proof that not enabling built-in has no built-in >> impact? >> > > Does it hurt to add? You never know if there are follow-on effects due > to definitions when setting a module (yes that would probably be a bug > but it can happen). Rules like "add Bloat-o-meter results to defconfig > change patches" work much better when you don't add "except when it's > obvious to Krzysztof that there should be no size change".. > > Andrew Reading this bloatometer actually takes time (including comparison of two long numbers) which is much longer than just saying "it's a module so no impact on kernel size"... which then you will understand is completely redundant statement. Placing here bloatometer actually encourages to check WHY it is there, like there was some useful information. Redundant information is not useful information. There is no rule to add bloatometer for modules. It's completely pointless. The benefit of bloatometer is when you make built-ins. But if we go to redundant information, maybe we should also mention here: 1. time of building Image.gz 2. time of building modules 3. impact on running dtbs_check 4. list of new user-space interfaces exposed Best regards, Krzysztof