From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from fhigh-b6-smtp.messagingengine.com (fhigh-b6-smtp.messagingengine.com [202.12.124.157]) (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 64F383207 for ; Thu, 2 Oct 2025 23:03:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=202.12.124.157 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759446203; cv=none; b=W+cvfoJ9B7D3i7pFmMmewJTb7bnujiJLBjCAqn7z/q0bpbzo3VV1g6UgYPPWh4cU7cf9VhALpbSE5Z0nqLbZswep4TeMMGpEGFO5njWedNcjFXxTkBI1S8fq3vVxrs4c3xTFWr4N6vK/gsOo6CQtbiBfRjKl1uO9VcoSjXZWlJ0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759446203; c=relaxed/simple; bh=CiiXX8EjxvPNtSGD+zcfpkU37k8AU03l8wEnyZQBbxM=; h=MIME-Version:Date:From:To:Cc:Message-Id:In-Reply-To:References: Subject:Content-Type; b=cFZBjljsK4Cut29E4Lo0skaq6R3x8xZoF8T7WI0LThPwhZXNFXSVcWcv2ciw4phb9DUUdwKuoC3FDBqpsm/ss2b0PH+ZcUuaxbpQTu8Nh5K9Jc6IwdCSnzglKx1QfxAgD5czxIjIhT++aKjB5sa3Tu/y3EXLgYTZ6WV7u5AHvKc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arndb.de; spf=pass smtp.mailfrom=arndb.de; dkim=pass (2048-bit key) header.d=arndb.de header.i=@arndb.de header.b=ptcGK8uw; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b=Od7d2TK/; arc=none smtp.client-ip=202.12.124.157 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arndb.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arndb.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=arndb.de header.i=@arndb.de header.b="ptcGK8uw"; dkim=pass (2048-bit key) header.d=messagingengine.com header.i=@messagingengine.com header.b="Od7d2TK/" Received: from phl-compute-05.internal (phl-compute-05.internal [10.202.2.45]) by mailfhigh.stl.internal (Postfix) with ESMTP id 4BD647A006E; Thu, 2 Oct 2025 19:03:20 -0400 (EDT) Received: from phl-imap-02 ([10.202.2.81]) by phl-compute-05.internal (MEProxy); Thu, 02 Oct 2025 19:03:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arndb.de; h=cc :cc:content-transfer-encoding:content-type:content-type:date :date:from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to; s=fm1; t=1759446200; x=1759532600; bh=1LDGnQ0gt7Sa0hoshBs+Cuhi9U0Tyg1pO8zVbYSkSqs=; b= ptcGK8uww5oB2UZho+1jOjjSKDcv5u24wPLKuZnnaxD2fJIUP23mJAI/YEOBbmOg 2r482COP8NuOmAMsnPGoyx9IOUDEX1DrThyZTldcFjnvkrf7SFzB3SRiVbTgSYLS GfNRzBMWx98Agd1/rwmcOQs+xO8PduEHL1xTdR2ZqFf3CiGeDvrJ3ZsbAZvFd/uP gpHKCUfylPeIYiu7ap5HvGTemwzIKmaRGZPB8Rk+RGb2AqKfLD8Hk5xqCa4r6Hqc lo6cxwGWNP+oGXlrdEQJHt+Jc1hxf5IzJqvS/Icd6hJ+eCmaT3iz5MdfT9x0JvkD S7UmEKfAvwL7t5S6o9jpcw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:content-type:date:date:feedback-id:feedback-id :from:from:in-reply-to:in-reply-to:message-id:mime-version :references:reply-to:subject:subject:to:to:x-me-proxy :x-me-sender:x-me-sender:x-sasl-enc; s=fm2; t=1759446200; x= 1759532600; bh=1LDGnQ0gt7Sa0hoshBs+Cuhi9U0Tyg1pO8zVbYSkSqs=; b=O d7d2TK/o8ERGISXaBGmTIhporaOoHjMieanul1AxMOIs5GXqTo+HqjUMZkMMFk9o ahBGAmop1c8PsbU3frGuwfll5AWNJ1VrAYk8RJ+FW9AARBqkd46mLOii/+uesyMI Z8ABC3CyM2d/5Qmnhq45SWeQDuxr5hWBeO6yu/pEgxUm6fO3J8AsHa2WtKtIkiBf WVAvZCjJZ7R2s2cN7Exz6OwE2AsWlBp5VVv5aqqR/PPyp2rjvQFgkZl+39HZwJ9z rqpMWjWb3aFlWRAYhXncnZFYyl0O3fAxXCSrV0TM1kdT03/S3NkhpJqiHX0YTncn JNxw0w32g79BrRMaK87mw== X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeeffedrtdeggdekjedvlecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpuffrtefokffrpgfnqfghnecuuegr ihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmdenucfjug hrpefoggffhffvvefkjghfufgtgfesthejredtredttdenucfhrhhomhepfdetrhhnugcu uegvrhhgmhgrnhhnfdcuoegrrhhnugesrghrnhgusgdruggvqeenucggtffrrghtthgvrh hnpeeggfejudejvdeijeeglefgtdfhudffieetfedugefhffekjeefhedtjeefjeetfeen ucffohhmrghinhepghhithhhuhgsrdgtohhmnecuvehluhhsthgvrhfuihiivgeptdenuc frrghrrghmpehmrghilhhfrhhomheprghrnhgusegrrhhnuggsrdguvgdpnhgspghrtghp thhtohepudefpdhmohguvgepshhmthhpohhuthdprhgtphhtthhopehlihhnuhigsegrrh hmlhhinhhugidrohhrghdruhhkpdhrtghpthhtoheprhhmkhdokhgvrhhnvghlsegrrhhm lhhinhhugidrohhrghdruhhkpdhrtghpthhtoheprhhoshhtvgguthesghhoohgumhhish drohhrghdprhgtphhtthhopegrrhgusgeskhgvrhhnvghlrdhorhhgpdhrtghpthhtohep vggsihhgghgvrhhssehkvghrnhgvlhdrohhrghdprhgtphhtthhopehkvggvsheskhgvrh hnvghlrdhorhhgpdhrtghpthhtohepnhgrthhhrghnsehkvghrnhgvlhdrohhrghdprhgt phhtthhopehtrhhivhhirghlsehkvghrnhgvlhdrohhrghdprhgtphhtthhopehlihhnuh hsrdifrghllhgvihhjsehlihhnrghrohdrohhrgh X-ME-Proxy: Feedback-ID: i56a14606:Fastmail Received: by mailuser.phl.internal (Postfix, from userid 501) id CF691700065; Thu, 2 Oct 2025 19:03:18 -0400 (EDT) X-Mailer: MessagingEngine.com Webmail Interface Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ThreadId: AOvO0JZNdWB- Date: Fri, 03 Oct 2025 01:02:58 +0200 From: "Arnd Bergmann" To: "Franz-Josef Haider" , "Linus Walleij" Cc: "Russell King" , "Ard Biesheuvel" , "Russell King" , "Eric Biggers" , "Nathan Chancellor" , "Steven Rostedt" , "Kees Cook" , "Dave Vasilevsky" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, trivial@kernel.org Message-Id: <7d0b68d4-6798-43a5-a6ca-99807bc183c5@app.fastmail.com> In-Reply-To: References: <6d9bb65c-d693-4d99-8183-b605cabf9380@app.fastmail.com> Subject: Re: [PATCH] ARM: Make sure CPU_ARM940T kernel can be built. Content-Type: text/plain Content-Transfer-Encoding: 7bit On Thu, Oct 2, 2025, at 17:34, Franz-Josef Haider wrote: > On 10/1/25 23:52, Arnd Bergmann wrote: > > Ok if the support for ARMv4T NOMMU has been removed, then maybe we can > leave this as resolved. > > It's actually just for a hobby project, nothing important. I just > thought these two patches might be helpful to other people who > encounter a similar issue on similar cpus, but if the support for > ARMv4T NOMMU has been dropped then there is no point maybe. > > Here are the patches for 6.2 in any case but it's very much a hacky > WIP, and there is some stuff in there that's not needed anymore on top > of later commits. https://github.com/krnlyng/linux-ipod/commits/n2g-wip > I also have a version on top of a recent (~29 SEPT 2025) commit locally > if that is interesting too. Looking at your tree, I find that the ARMv4T NOMMU support is not even that bad to put back, especially since commit 84fc86360623 ("ARM: make ARCH_MULTIPLATFORM user-visible") made it possible to add a 'depends on !ARCH_MULTIPLATFORM' in the platform specific code. I still think that this specific oneline patch is not helpful, but the other one you sent is technically still a correct fix and we should either merge that or drop the remnants of the ARM740T/940T/946E code now that we know it's broken. Similarly, the later ARM1176 based code that you based your patches on does look worth cleaning up and merging if there are still users. For the specific s5l870x (arm940) SoC support, I see what you mean with missing cleanups, but more importantly I think that we will want to drop nommu support from arch/arm/ in a few years as the remaining users all tend to fall into a similar class as yours where the developers work on them for the fun of it but without anyone else depending on it to run on the latest kernels. Since there is a significant cost in continuing to test and fix the special cases for nommu support overall, I would prefer to draw the line at S5L8720 support and not merge S5L8702 or earlier. Arnd