From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-eopbgr740122.outbound.protection.outlook.com ([40.107.74.122]:20938 "EHLO NAM01-BN3-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727956AbfGKXZv (ORCPT ); Thu, 11 Jul 2019 19:25:51 -0400 From: Hoan Tran OS Subject: [PATCH v2 0/5] mm: Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA Date: Thu, 11 Jul 2019 23:25:44 +0000 Message-ID: <1562887528-5896-1-git-send-email-Hoan@os.amperecomputing.com> Content-Language: en-US Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: linux-s390-owner@vger.kernel.org List-ID: To: Catalin Marinas , Will Deacon , Andrew Morton , Michal Hocko , Vlastimil Babka , Oscar Salvador , Pavel Tatashin , Mike Rapoport , Alexander Duyck , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H . Peter Anvin" , "David S . Miller" , Heiko Carstens , Vasily Gorbik , Christian Borntraeger Cc: "open list:MEMORY MANAGEMENT" , "linux-arm-kernel@lists.infradead.org" , "linux-s390@vger.kernel.org" , "sparclinux@vger.kernel.org" , "x86@kernel.org" , "linuxppc-dev@lists.ozlabs.org" , "linux-kernel@vger.kernel.org" , Open Source Submission , Hoan Tran OS In NUMA layout which nodes have memory ranges that span across other nodes, the mm driver can detect the memory node id incorrectly. For example, with layout below Node 0 address: 0000 xxxx 0000 xxxx Node 1 address: xxxx 1111 xxxx 1111 Note: - Memory from low to high - 0/1: Node id - x: Invalid memory of a node When mm probes the memory map, without CONFIG_NODES_SPAN_OTHER_NODES config, mm only checks the memory validity but not the node id. Because of that, Node 1 also detects the memory from node 0 as below when it scans from the start address to the end address of node 1. Node 0 address: 0000 xxxx xxxx xxxx Node 1 address: xxxx 1111 1111 1111 This layout could occur on any architecture. This patch enables CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA to fix this issue. V2: * Revise the patch description Hoan Tran (5): mm: Enable CONFIG_NODES_SPAN_OTHER_NODES by default for NUMA powerpc: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES x86: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES sparc: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES s390: Kconfig: Remove CONFIG_NODES_SPAN_OTHER_NODES arch/powerpc/Kconfig | 9 --------- arch/s390/Kconfig | 8 -------- arch/sparc/Kconfig | 9 --------- arch/x86/Kconfig | 9 --------- mm/page_alloc.c | 2 +- 5 files changed, 1 insertion(+), 36 deletions(-) --=20 2.7.4