From patchwork Fri Nov 5 20:44:28 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12605777 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E0BF1C433F5 for ; Fri, 5 Nov 2021 20:44:31 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 989906135A for ; Fri, 5 Nov 2021 20:44:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 989906135A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 28CE49400B7; Fri, 5 Nov 2021 16:44:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 0FBD89400B3; Fri, 5 Nov 2021 16:44:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F2DA29400B6; Fri, 5 Nov 2021 16:44:30 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0073.hostedemail.com [216.40.44.73]) by kanga.kvack.org (Postfix) with ESMTP id DDF159400B3 for ; Fri, 5 Nov 2021 16:44:30 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 97EBB77816 for ; Fri, 5 Nov 2021 20:44:30 +0000 (UTC) X-FDA: 78776054700.13.ADE6D32 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf24.hostedemail.com (Postfix) with ESMTP id 089C4B0000A9 for ; Fri, 5 Nov 2021 20:44:29 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 904A361357; Fri, 5 Nov 2021 20:44:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1636145069; bh=3A4nZhu029sBU0tdcSR7GUPafBaYK4IeubSP84Q2m/Y=; h=Date:From:To:Subject:In-Reply-To:From; b=o7a6hnO3KVY4qHDb3PBMW02C5XxcppbniN8Q3BvkSf/8+qrXeUYiyfsAREkSnTPBZ 6Clxu1YiI75voca6J1CONSQMrlQsPnquuTgeft9tbZIR8SISdkkDJxeAdWLzSrB3hR P/DErO47g8E9z3bWNFKLQq6og4zhMb9tytDxE860= Date: Fri, 05 Nov 2021 13:44:28 -0700 From: Andrew Morton To: akpm@linux-foundation.org, alexs@kernel.org, benh@kernel.crashing.org, bp@alien8.de, corbet@lwn.net, dave.hansen@linux.intel.com, david@redhat.com, gregkh@linuxfoundation.org, hpa@zytor.com, jasowang@redhat.com, linux-mm@kvack.org, luto@kernel.org, mhocko@suse.com, mingo@redhat.com, mm-commits@vger.kernel.org, mpe@ellerman.id.au, mst@redhat.com, osalvador@suse.de, paulus@samba.org, peterz@infradead.org, rafael@kernel.org, rppt@kernel.org, shuah@kernel.org, tglx@linutronix.de, torvalds@linux-foundation.org Subject: [patch 188/262] mm/memory_hotplug: restrict CONFIG_MEMORY_HOTPLUG to 64 bit Message-ID: <20211105204428.ikPIxSeQt%akpm@linux-foundation.org> In-Reply-To: <20211105133408.cccbb98b71a77d5e8430aba1@linux-foundation.org> User-Agent: s-nail v14.8.16 Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=o7a6hnO3; dmarc=none; spf=pass (imf24.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 089C4B0000A9 X-Stat-Signature: r8575f1r95g7o3pxnuj4mfwj3emcjrw3 X-HE-Tag: 1636145069-551242 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: David Hildenbrand Subject: mm/memory_hotplug: restrict CONFIG_MEMORY_HOTPLUG to 64 bit 32 bit support is broken in various ways: for example, we can online memory that should actually go to ZONE_HIGHMEM to ZONE_MOVABLE or in some cases even to one of the other kernel zones. We marked it BROKEN in commit b59d02ed0869 ("mm/memory_hotplug: disable the functionality for 32b") almost one year ago. According to that commit it might be broken at least since 2017. Further, there is hardly a sane use case nowadays. Let's just depend completely on 64bit, dropping the "BROKEN" dependency to make clear that we are not going to support it again. Next, we'll remove some HIGHMEM leftovers from memory hotplug code to clean up. Link: https://lkml.kernel.org/r/20210929143600.49379-4-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Oscar Salvador Cc: Alex Shi Cc: Andy Lutomirski Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Dave Hansen Cc: Greg Kroah-Hartman Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: Jason Wang Cc: Jonathan Corbet Cc: Michael Ellerman Cc: "Michael S. Tsirkin" Cc: Michal Hocko Cc: Mike Rapoport Cc: Paul Mackerras Cc: Peter Zijlstra Cc: "Rafael J. Wysocki" Cc: Shuah Khan Cc: Thomas Gleixner Signed-off-by: Andrew Morton --- mm/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/Kconfig~mm-memory_hotplug-restrict-config_memory_hotplug-to-64-bit +++ a/mm/Kconfig @@ -125,7 +125,7 @@ config MEMORY_HOTPLUG select MEMORY_ISOLATION depends on SPARSEMEM depends on ARCH_ENABLE_MEMORY_HOTPLUG - depends on 64BIT || BROKEN + depends on 64BIT select NUMA_KEEP_MEMINFO if NUMA config MEMORY_HOTPLUG_DEFAULT_ONLINE