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 1B973C531C9 for ; Fri, 24 Jul 2026 13:53:14 +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=uNvIwIL0F+WGb1cP296osJ4ZZdbCodbHqraWe1YZzog=; b=A9oFXIhh/9wOnuStUVoIiHq2N1 Gf9G6H2W8tdz9MSboq4QazPv6uVLgM3Uft0jDrmP2zERTSQxpRFAm5RWlALvHjXOyPY2VhREIcgDX QTWnB3YnLV6XQflUhcXQLDz4WzKn45+HilCmPbwcOpSIB62mN0hp1PvtmuxRup4Pwi16LSLdZoK5+ BqYJeuPmCXuyyWcA26D3E/u2VSdN1hPgk8/M8Ed7RaoLDDfErFG+48KUa988xfGPLL4DD2kXuknCr W8qa4ISphCdi1aQE2l2ZCiNawMDopMGQycTsjivFrJ/TNM56B8PNLgV03wnZdy8Di9dtcMOUtV+ZY sjoOqWDw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wnGKn-0000000GWav-3kYF; Fri, 24 Jul 2026 13:53:05 +0000 Received: from tor.source.kernel.org ([172.105.4.254]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wnGKm-0000000GWap-27Ae for linux-arm-kernel@lists.infradead.org; Fri, 24 Jul 2026 13:53:04 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 94DC5600AA; Fri, 24 Jul 2026 13:53:03 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D88DA1F000E9; Fri, 24 Jul 2026 13:53:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784901183; bh=uNvIwIL0F+WGb1cP296osJ4ZZdbCodbHqraWe1YZzog=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=DVHAf0IXKut/rgOXRCr3U1pceg9fxuVvhvImCQ8KNMSrzvzTohQO0zFfyZCm9Q01l jS1KjX/6eVwf5/LlLcZqa2go7vFFK80H5kHCOiKl2L48aj2OZr80Z0jh6H+lGDSKe5 Efbp/ZC6xCjRdfROMt+CDOOgI0eCWKhr5bx8Y8dfA8vXRNETYrY70iHYHEZl0tAi3c 4aT74NHW297AKS0BK+/NbrnvXEzc843AXm6BV3fARrdzI4RTzqzJb7MHbkzpRkjAWF /pu0N8OzWMFnrePzg1FAO+TRKwgxdDyAsXa+6FsXcx3KnIWK4QdbNliRaWnTLz8BYr N0+oN4yQmMIMA== Date: Fri, 24 Jul 2026 06:51:11 -0700 From: Eric Biggers To: Sumit Garg Cc: linux-crypto@vger.kernel.org, Herbert Xu , linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Demi Marie Obenour , Bartosz Golaszewski , Kuldeep Singh , Dmitry Baryshkov , Greg Kroah-Hartman Subject: Re: [PATCH] crypto: qce - Remove driver Message-ID: <20260724135111.GA1876@sol> References: <20260724050645.223799-1-ebiggers@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: 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, Jul 24, 2026 at 03:26:41PM +0530, Sumit Garg wrote: > Hi Eric, > > On Thu, Jul 23, 2026 at 10:06:45PM -0700, Eric Biggers wrote: > > This obsolete driver was already marked as BROKEN. However, keeping > > BROKEN code around in the tree is unnecessary and causes problems. It's > > much better to just remove it entirely. Let's do that. > > > > Crypto acceleration remains well-supported on Qualcomm SoCs via the > > Qualcomm Inline Crypto Engine and the ARMv8 Crypto Extensions, which are > > what Linux actually uses in practice. The obsolete QCE driver is a > > dead-end approach. It's extremely slow and just doesn't work well. > > Not sure why only performance is seen as the major driver to drop crypto > accelerators from kernel Maybe you missed all the other reasons I gave too. > while neglecting the security use-cases they support as well like: > > - Support for hardware backed keys > - Support for secure media playback use-cases The QCE driver doesn't support these features. So they aren't relevant to this patch. > I know it's not good to add functionality based on a prospective > future use-cases but at the same time dropping functionality for it to be > added again is just too much unnecessary churn. This conflates current functionality, which doesn't meet upstream kernel inclusion standards, with mostly-unrelated speculative future functionality. Anything new should just start from a clean slate with just what is actually needed. > I am sure you are aware about support for hardware backed key use-cases > for many of those crypto accelerators. NXP CAAM engine is one such > example. The CAAM driver does register a "cbc(paes)" algorithm with the crypto API (i.e., CBC-AES with a hardware backed key). However, there's no upstream user of that algorithm as far as I can tell. But this is unrelated to this patch, which is for the QCE driver. - Eric