From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 071CB22A7E8 for ; Thu, 27 Feb 2025 10:34:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740652492; cv=none; b=MR/XYsM+EqEiTdsRMmzKelluVaiRLF/aFGZ3T8BQ5Lmmw9KAFrghKyC28BWm6bbchPEoIuK73uY3igo8s4aFzupvLa74EdD0o8zie/XQdPNdSb9fgyKgtubVIXSH+RpDpoTk8nP6cI1+UGFZmYOMEIzHWSpvqFM8VrPP9fnbrXo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740652492; c=relaxed/simple; bh=Xac24VrsdrBYAfE9ybZ7Brx1MyS7wGqE7VM58B4MrVI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BPbY/W8Gu7yrPW7QU7Hkyu4YaIKBUrPUvJaX8BWk8k+/5/Nl14XX7sGLglwzh+/O8RwD2Y+TShxC5pVWpJYoyRhINs0j+my6quHWon8203mPGqa743nG5yiPA15T3hcdd4eFWheUcDC5/kKFD+XpmZ/POtCfxNotbuqH/5i/EfA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ae2u9Q8F; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ae2u9Q8F" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A938EC4CEE4; Thu, 27 Feb 2025 10:34:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1740652491; bh=Xac24VrsdrBYAfE9ybZ7Brx1MyS7wGqE7VM58B4MrVI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ae2u9Q8FXGE2QeIA24n/SV3p5ziIrf2/Uddd6wY5t8MZyal8x8IETd4YKjX218c/L ENpjTugDAuff6a/WUKa1XFnq/48LKaxhCoc33JH7My+t2TUw6yFijYIraWRAZA9c1L isWwP9imucaSrItoYP9E+HfRSoiJZBtdn5Cb9FcJEctwhBanxbhZyD1APla1F256dk fKaUGcV0rR/UMnaBVo5MmWJsalwXA+tBI0nfuX9Ig9BC/l176kCexJoNJi3Tu9f4Yk xYfKbl3cQbsmBarn1f5joGkUbLrwmTZGfxLoWOwk13GUY0E0MguFp9hCq/U+3LG5pj OH0p+9U5xPgAw== Date: Thu, 27 Feb 2025 11:34:40 +0100 From: Ingo Molnar To: Arnd Bergmann Cc: linux-kernel@vger.kernel.org, x86@kernel.org, Arnd Bergmann , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Linus Torvalds , Andy Shevchenko , Matthew Wilcox Subject: Re: [PATCH v3 00/10] x86: 32-bit cleanups Message-ID: References: <20250226213714.4040853-1-arnd@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250226213714.4040853-1-arnd@kernel.org> * Arnd Bergmann wrote: > From: Arnd Bergmann > > While looking at 32-bit arm cleanups, I came across some related topics > on x86 and ended up making a series for those as well. > > Primarily this is about running 32-bit kernels on 64-bit hardware, > which usually works but should probably be discouraged more clearly by > only providing support for features that are used on real 32-bit hardware: > > I found only a few 2003-era high-end servers (HP DL740 and DL760 G2) > that were the only possible remaining uses of HIGHMEM64G and BIGSMP after > the removal of 32-bit NUMA machines in 2014. Similarly, there is only > one generation of hardware with support for VT-x. All these features > can be removed without hurting users. > > In the CPU selection, building a 32-bit kernel optimized for AMD K8 > or Intel Core2 is anachronistic, so instead only 32-bit CPU types need > to be offered as optimization targets. The "generic" target on 64-bit > turned out to be slightly broken, so I included a fix for that as well. > > Changes since v2: > > - Add a patch for EISA > - keep PHYS_ADDR_T_64BIT enabled for PAE kernels > - drop the Kconfig.platforms and CONFIG_X86_64_NATIVE patches for now > - improve changelog texts > > Changes since v1: > > - Don't include patch to drop 32-bit KVM support for now > - Drop patch for 64-bit Silverlake support > - Drop 64-bit ISA level selection, only fix default > - Rework MID patch based on comments > - Add a patch to reorganize platform selection > - Add a patch to add -march=native compilation > > > Arnd Bergmann (10): > x86/Kconfig: Geode CPU has cmpxchg8b > x86: drop 32-bit "bigsmp" machine support > x86: rework CONFIG_GENERIC_CPU compiler flags > x86: drop configuration options for early 64-bit CPUs > x86: remove HIGHMEM64G support > x86: drop SWIOTLB for PAE > x86: drop support for CONFIG_HIGHPTE > x86: document X86_INTEL_MID as 64-bit-only > x86: remove old STA2x11 support > x86: only allow EISA for 32-bit > > Documentation/admin-guide/kdump/kdump.rst | 4 - > .../admin-guide/kernel-parameters.txt | 11 - > Documentation/arch/x86/usb-legacy-support.rst | 11 +- > arch/x86/Kconfig | 156 +++--------- > arch/x86/Kconfig.cpu | 97 ++------ > arch/x86/Makefile | 16 +- > arch/x86/Makefile_32.cpu | 5 +- > arch/x86/configs/xen.config | 2 - > arch/x86/include/asm/page_32_types.h | 4 +- > arch/x86/include/asm/pgalloc.h | 5 - > arch/x86/include/asm/sta2x11.h | 13 - > arch/x86/include/asm/vermagic.h | 4 - > arch/x86/kernel/apic/Makefile | 3 - > arch/x86/kernel/apic/apic.c | 3 - > arch/x86/kernel/apic/bigsmp_32.c | 105 -------- > arch/x86/kernel/apic/local.h | 13 - > arch/x86/kernel/apic/probe_32.c | 29 --- > arch/x86/mm/init_32.c | 9 +- > arch/x86/mm/pgtable.c | 27 +- > arch/x86/pci/Makefile | 2 - > arch/x86/pci/sta2x11-fixup.c | 233 ------------------ > drivers/misc/mei/Kconfig | 2 +- > 22 files changed, 66 insertions(+), 688 deletions(-) Sweet! I have applied your series to tip:x86/cpu with some minor tweaks and a conflict resolution for pending work in x86/mm. Let's see if anyone complains about the removal of these obsolete features. Thanks, Ingo