Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753875AbcDVLGj (ORCPT ); Fri, 22 Apr 2016 07:06:39 -0400 Received: from mx2.suse.de ([195.135.220.15]:43971 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753596AbcDVLG0 (ORCPT ); Fri, 22 Apr 2016 07:06:26 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Xishi Qiu , Joonsoo Kim , David Rientjes , "Laura Abbott" , Hui Zhu , Wang Xiaoqiang , Andrew Morton , Linus Torvalds , Jiri Slaby Subject: [PATCH 3.12 43/78] mm: fix invalid node in alloc_migrate_target() Date: Fri, 22 Apr 2016 13:05:26 +0200 Message-Id: <8fd077773ca78811c68c7a537cf21761da5046fc.1461323133.git.jslaby@suse.cz> X-Mailer: git-send-email 2.8.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1752 Lines: 50 From: Xishi Qiu 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 6f25a14a7053b69917e2ebea0d31dd444cd31fd5 upstream. It is incorrect to use next_node to find a target node, it will return MAX_NUMNODES or invalid node. This will lead to crash in buddy system allocation. Fixes: c8721bbbdd36 ("mm: memory-hotplug: enable memory hotplug to handle hugepage") Signed-off-by: Xishi Qiu Acked-by: Vlastimil Babka Acked-by: Naoya Horiguchi Cc: Joonsoo Kim Cc: David Rientjes Cc: "Laura Abbott" Cc: Hui Zhu Cc: Wang Xiaoqiang Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Jiri Slaby --- mm/page_isolation.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/page_isolation.c b/mm/page_isolation.c index d1473b2e9481..88bdbf48cf6c 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -259,11 +259,11 @@ struct page *alloc_migrate_target(struct page *page, unsigned long private, * now as a simple work-around, we use the next node for destination. */ if (PageHuge(page)) { - nodemask_t src = nodemask_of_node(page_to_nid(page)); - nodemask_t dst; - nodes_complement(dst, src); + int node = next_online_node(page_to_nid(page)); + if (node == MAX_NUMNODES) + node = first_online_node; return alloc_huge_page_node(page_hstate(compound_head(page)), - next_node(page_to_nid(page), dst)); + node); } if (PageHighMem(page)) -- 2.8.1