From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 7BDF3C5B555 for ; Sun, 1 Jun 2025 23:22:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VLdinv37uoJCg/NqMkaiZgFpI3acFDq5XCKcz59TcpQ=; b=2CjbAwnYxr+9zTR2WTLUt4ROZ+ 8Qu4lqIx5Jhb+qQTEuEbXSkx10qjoLMfiiNu47fD/UVOg3yAd45Dvdq1uni5zTBGS+s0B6Q/zeuNT EqPKSlYCQBzusBAvZAQi9NDbJeHXaxcgKCJm4j5vj42tIzHI88s7HatzMnF0IgH8mX+JK1PDmgbmg Qr5DamX9f09osvGUgzDqRh7anlcfEN0MqhNJXZ6eECaz0AwrzZTgJ5iQN/+f/9X2XxrR5Ds/b56LB FLx0dW091XSPGKP9aEdHFyTzThVeh3s+zen85acoTTpqRELWkKBDt/QdUbvHPkb3sqIk1sMs6cv2P CHrRrsJg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uLs03-0000000650V-2vGi; Sun, 01 Jun 2025 23:21:55 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uLrfO-0000000631F-2lhY; Sun, 01 Jun 2025 23:00:34 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id CA61F60EDF; Sun, 1 Jun 2025 23:00:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 14CC5C4CEE7; Sun, 1 Jun 2025 23:00:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1748818833; bh=9iuAqFgWuAM8zbaClmJE1PWkDiz9aDszJI49BnUralg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=vHFxc2VElAHlFA2+p6pUxtFWEe5J4xv+o56KAxPCmT8t7sop9JD+tvRSV5M6+149b 3yslurmUrK9306e+AjqkjU66ZE4+J12qO4pfC9GKOwcLYIKirbFU/Rg2oRbbVA43ns 5uDfSlrlHs9e9hvwYN9GazeDaNtZ3XeMSpkJHQHb3lkfbDihKnyqOzItzJyKZ/V5SA kll91RZkjqNe9evwrPUGhmeKBh/iuKFMYirrTrajg0Qa5HWH48c/p5D7scSRNhf3bP g9JW0K0QMuooWlvxhFXufeAQiYS/ENsn141k7rnLZBFnOMguZuObdXNfv/1/r4saJT S2ckVl3S2NSgA== Date: Sun, 1 Jun 2025 16:00:14 -0700 From: Eric Biggers To: Linus Torvalds Cc: Alex Williamson , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, sparclinux@vger.kernel.org, linux-s390@vger.kernel.org, x86@kernel.org, Ard Biesheuvel , "Jason A . Donenfeld" Subject: Re: [PATCH v4 08/13] crypto: s390/sha256 - implement library instead of shash Message-ID: <20250601230014.GB1228@sol> References: <20250428170040.423825-1-ebiggers@kernel.org> <20250428170040.423825-9-ebiggers@kernel.org> <20250529110526.6d2959a9.alex.williamson@redhat.com> <20250529173702.GA3840196@google.com> <20250529211639.GD23614@sol> <20250530001858.GD3840196@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250530001858.GD3840196@google.com> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, May 30, 2025 at 12:18:58AM +0000, Eric Biggers wrote: > On Thu, May 29, 2025 at 04:54:34PM -0700, Linus Torvalds wrote: > > On Thu, 29 May 2025 at 14:16, Eric Biggers wrote: > > > > > > So using crc32c() + ext4 + x86 as an example (but SHA-256 would be very > > > similar), the current behavior is that ext4.ko depends on the crc32c_arch() > > > symbol. > > > > Yes, I think that's a good example. > > > > I think it's an example of something that "works", but it certainly is > > a bit hacky. > > > > Wouldn't it be nicer if just plain "crc32c()" did the right thing, > > instead of users having to do strange hacks just to get the optimized > > version that they are looking for? > > For crc32c() that's exactly how it works (since v6.14, when I implemented it). > The users call crc32c() which is an inline function, which then calls > crc32c_arch() or crc32c_base() depending on the kconfig. So that's why I said > the symbol dependency is currently on crc32c_arch. Sorry if I wasn't clear. > The SHA-256, ChaCha, and Poly1305 library code now has a similar design too. > > If we merged the arch and generic modules together, then the symbol would become > crc32c. But in either case crc32c() is the API that all the users call. > > - Eric > I implemented my proposal, for lib/crc first, in https://lore.kernel.org/lkml/20250601224441.778374-1-ebiggers@kernel.org. I think it's strictly better than the status quo, and once applied to lib/crypto it will solve some of the problems we've been having there too. But let me know if you still have misgivings. - Eric