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 91658C5478C for ; Mon, 26 Feb 2024 21:30:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To: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=SUh/jio5H5/fAD3TQcY3Yu4B+DQCzFDbN1wED/5rhX8=; b=Qy+XUmRRoLkAqh8dILpqJKEJWG rq1gV8NOjJsDA5fbYGQY6PABaeKc5ZDFv7F1s2bst1bB8+yIjvkPo/lvWDpKzv0tzwoLQ4iagPRV/ wHhYOsgU4S28IMNBnCGPBP0F1Z3JmTvQhtviTp1fjyUf0I/L7bkEljJ8+Bhdc59WDC9D3q4/jTjBr uaKCrbbOEw6dMrNzK+cKujvwKLEwQOeMfqyGIwbmToXcKG7LGiROnztriRjjRWxr+Ca396BllR45D 95uuJCNqBb+m9v5Eh3tjh8MJl/kr57/TBKnqZYyIJNAJOl4eLaDHk+WfbkfvWMS+H0Ku6ItYmXrUU YrBcx8HQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1reiY9-00000002hhz-16E3; Mon, 26 Feb 2024 21:30:13 +0000 Received: from sin.source.kernel.org ([2604:1380:40e1:4800::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1reiY5-00000002hgT-3C0a for linux-riscv@lists.infradead.org; Mon, 26 Feb 2024 21:30:11 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id BB410CE1748; Mon, 26 Feb 2024 21:30:05 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51282C433F1; Mon, 26 Feb 2024 21:30:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1708983005; bh=zjn4FAEggIcuF3yKsLZHJqmJCdDBGnSpMPbFVggTO3g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=DItVn8FzrzmNOghOMNojZv1uKdkDrHaNOjPUSbdrFyk9RGrqvJpYljlQEb1YwYPHq mGpH26IyFXbI8Ejwq+3VKEB+SjnIE5q5AjBUiUZJaAyphPyM8em7Q2gFdhXvYgoVbm N2nkA1sfeWI1mBHNCq6RE6KW1w8izhS6NmXmiKC6N1yr+MSk08/ARMZOtrnWuKAHZK zaT7ACH/FKu4FjFP1NespKDQ4zFigtHVQVYFI7nxIDDDyZNtD/PewlcCmuGwtYB5Qp 8FpRak7ynTOBnnCfgZo3Z6THMS9eQOnlyr7VVOwvXRRaeCaArtf/W6iSrWeBoeAb6Q 81IEiB8G9Oskw== Date: Mon, 26 Feb 2024 21:29:59 +0000 From: Conor Dooley To: Charles Lohr Cc: =?iso-8859-1?Q?Cl=E9ment_L=E9ger?= , Samuel Holland , Paul Walmsley , Palmer Dabbelt , Albert Ou , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Conor Dooley , Andrew Jones , Damien Le Moal , =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , Atish Patra Subject: Re: [PATCH] riscv: deprecate CONFIG_MMU=n Message-ID: <20240226-jolt-earwig-91c7b0eb868f@spud> References: <20240226140649.293254-1-cleger@rivosinc.com> <40dee2c1-ff24-40b2-a13c-6934139ba869@sifive.com> <20240226-pajamas-okay-51e16426b0f5@spud> MIME-Version: 1.0 In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240226_133010_175518_ED5117E1 X-CRM114-Status: GOOD ( 27.28 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============5367403185308235391==" Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org --===============5367403185308235391== Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="r/gcDu4EFBEr9fnP" Content-Disposition: inline --r/gcDu4EFBEr9fnP Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Feb 26, 2024 at 11:00:41AM -0800, Charles Lohr wrote: > WOAH! Please DO NOT deprecate NOMMU. I use the NOMMU build constantly > and NOMMU Linux on RISC-V is the avenue used by many FPGA soft cores > for Linux, as well as some limited systems. >=20 > I get new copies of the kernel when there are releases and test them > frequently to make sure everything is still working as expected. That is great - it is good to know that people are actively testing. I was aware that a lot of the soft core folks did run nommu kernels (and I know some do use XIP also) but everything I ever saw was running on old kernels (5.x). > On Mon, Feb 26, 2024 at 8:03=E2=80=AFAM Conor Dooley w= rote: > > > > On Mon, Feb 26, 2024 at 04:25:24PM +0100, Cl=C3=A9ment L=C3=A9ger wrote: > > > I guess I could also mark XIP as deprecated. > > > > I'm not so sure, people recently added XIP support to QEMU (and sent > > kernel fixes in December). XIP is also not nearly as much of a problem > > to support, there's far less that it does differently, the main barrier > > was the inability to test it which is no longer the case. > > That said, XIP is gonna kill itself off I feel as it does not support > > runtime patching and therefore is extremely limited on extensions, given > > we use alternatives for all of that (although I suppose if someone has a > > usecase they could make nasty macros worse and implement a compiletime > > switch in the alternatives too). > For us we just don't care about XIP. I mean if someone did push it > through to fruition, I'd also test and use it, but I urge you please > do not deprecate this. XIP does work. What I was talking about here was supporting something "fancier" than rv{32,64}imafdc. > While it's sometimes needed a bit of a > creative build to get everything working, I've never needed to patch > anything in the kernel beyond patching in a custom console for serial > output. >=20 > I am happy to discuss the possibility of me and or one of the other > RISC-V soft (FPGA) core people stepping up to try to be more active, > but so far we've just been very well serviced by the current NOMMU > Linux setup. Most of the issues aren't with nommu actually working, it is the extra effort in development as it has to be accounted for. I would estimate that 2/3 of the build issues I report on this list are nommu. The best thing that you can do to ensure support for things you use is: a) scream when someone wants to remove it b) actively let people know you're using it Seems like you're doing a) but maybe getting someone that provides Tested-bys whenever you test the releases would be good. Cheers, Conor. --r/gcDu4EFBEr9fnP Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCZd0C1wAKCRB4tDGHoIJi 0u/MAQCeW2ubw3mJ60qwhWI9XYdVEt3d//hBXTomA1zTo7JPogEAjynbFf7kHRRo t6KM+bwe0KkDGAzlO9lor7hooH2m2A8= =JHXN -----END PGP SIGNATURE----- --r/gcDu4EFBEr9fnP-- --===============5367403185308235391== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv --===============5367403185308235391==--