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 24154CCD1AB for ; Wed, 22 Oct 2025 20:47:54 +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=amyp0bQQLpeK8dKZTAb4WHpNFpX9yDj0u1UHnTXihyk=; b=B2OVsAY9Gb6CuC5iBufB4qrNpK 4VMQyR1K5EPNBAUy7oie2TUIwQFhpBctBCTVgMyBj6X2iv/SEgi+8i0y01ytzNQFBBLzmTaRW4rVH GnlYNJqZj94Mol9uKbcQkWnrTKamEaRYrbB26xJhH16r/e8jUN6JagzpqEJ9quziBuXKxRrSu8tAu qh1flgFlBLfnLBGnY8bGuwwuO5vOo75BadkXM5NypkwkPtGsKeMTGu9ImNDTf/YxGHF3Kd/GmgqLq LQMtcd93YNNOYt+ZzV4BtkrOakAA+MtLgiiCM/X2tRHUja9oCvtwH9Z0D+zpi+DEPcc0wbwPLVJhd KwiVX36Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vBfkF-00000004HjB-1zyd; Wed, 22 Oct 2025 20:47:43 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vBfkC-00000004Hi6-2E42 for linux-arm-kernel@lists.infradead.org; Wed, 22 Oct 2025 20:47:41 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id D513A4533F; Wed, 22 Oct 2025 20:47:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6F71BC4CEE7; Wed, 22 Oct 2025 20:47:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761166047; bh=e4wpAeuwnWxwPsv6xR22bTAFdrGhHjpoATj1khsZ/3E=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=eMDWLrfV+vZznUoPf7CPswB3dBThpbX2cO+2bWvkQ50o2TCrvoCdE1Cd8xXrUFRoi 4RQOPMKhr+0tnSOK+DiKcMtj1oDkCTxPA4mHmnI44BotWVAjb9ldTnLMyTQjyS1Glb ijl24xdpzSdzrCZEKhn++IHDQPpZbUdTkCvlJsrAxJb/YRqToadM7K56X3TBjl4HEM Kyj7DofAye5roHM4RI4hcbcHBS9HAWzaMufkLYbmgqUo5c4mw2HV49+ecHPYhV766I BEuFIsEhcM7FbKPeKnO/YdST5KXQbtfPvLsfWmyESS1GnxaOKoG42xaOoXjHPKwp4J 2Yalv6aXeJwRQ== Date: Wed, 22 Oct 2025 21:47:21 +0100 From: Conor Dooley To: Andrew Morton Cc: Jonathan Cameron , Catalin Marinas , linux-cxl@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, Dan Williams , "H . Peter Anvin" , Peter Zijlstra , james.morse@arm.com, Will Deacon , Davidlohr Bueso , linuxarm@huawei.com, Yushan Wang , Lorenzo Pieralisi , Mark Rutland , Dave Hansen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, Andy Lutomirski , Dave Jiang Subject: Re: [PATCH v4 0/6] Cache coherency management subsystem Message-ID: <20251022-harsh-juggling-2d4778b0649e@spud> References: <20251022113349.1711388-1-Jonathan.Cameron@huawei.com> <20251022122241.d2aa0d7864f67112aa7691bf@linux-foundation.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="S6HWZzkHmuKfgcDz" Content-Disposition: inline In-Reply-To: <20251022122241.d2aa0d7864f67112aa7691bf@linux-foundation.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251022_134740_621748_4A15FFC2 X-CRM114-Status: GOOD ( 25.83 ) 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 --S6HWZzkHmuKfgcDz Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Oct 22, 2025 at 12:22:41PM -0700, Andrew Morton wrote: > On Wed, 22 Oct 2025 12:33:43 +0100 Jonathan Cameron wrote: >=20 > > Support system level interfaces for cache maintenance as found on some > > ARM64 systems. This is needed for correct functionality during various > > forms of memory hotplug (e.g. CXL). Typical hardware has MMIO interface > > found via ACPI DSDT. > >=20 > > Includes parameter changes to cpu_cache_invalidate_memregion() but no > > functional changes for architectures that already support this call. >=20 > I see additions to lib/ so presumably there is an expectation that > other architectures might use this. >=20 > Please expand on this. Any particular architectures in mind? Any > words of wisdom which maintainers of those architectures might benefit > from? It seems fairly probable that we're gonna end up with riscv systems where drivers are being used for both this and the existing non-standard cache ops stuff. > > How to merge? When this is ready to proceed (so subject to review > > feedback on this version), I'm not sure what the best route into the > > kernel is. Conor could take the lot via his tree for drivers/cache but > > the generic changes perhaps suggest it might be better if Andrew > > handles this? Any merge conflicts in drivers/cache will be trivial > > build file stuff. Or maybe even take it throug one of the affected > > trees such as CXL. >=20 > Let's not split the series up. Either CXL or COnor's tree is fine my > me. CXL is fine by me, greater volume there probably by orders of magnitude. --S6HWZzkHmuKfgcDz Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRh246EGq/8RLhDjO14tDGHoIJi0gUCaPlC2QAKCRB4tDGHoIJi 0tdvAQDJHGwCvxYrXGJs6nPPk7w5pV6+UajlzpKhldIVtCgm2QD/XrQK+qDLbAJA ymsJdZLdZoCSVVQ542yRJc4RjGzDnA8= =4U3B -----END PGP SIGNATURE----- --S6HWZzkHmuKfgcDz--