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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D9583C4360F for ; Fri, 5 Apr 2019 13:51:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A048321738 for ; Fri, 5 Apr 2019 13:51:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731183AbfDENvX (ORCPT ); Fri, 5 Apr 2019 09:51:23 -0400 Received: from outbound-smtp02.blacknight.com ([81.17.249.8]:36994 "EHLO outbound-smtp02.blacknight.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730801AbfDENvX (ORCPT ); Fri, 5 Apr 2019 09:51:23 -0400 Received: from mail.blacknight.com (pemlinmail01.blacknight.ie [81.17.254.10]) by outbound-smtp02.blacknight.com (Postfix) with ESMTPS id 98A5F98DEB for ; Fri, 5 Apr 2019 13:51:21 +0000 (UTC) Received: (qmail 28412 invoked from network); 5 Apr 2019 13:51:21 -0000 Received: from unknown (HELO stampy.163woodhaven.lan) (mgorman@techsingularity.net@[37.228.225.79]) by 81.17.254.9 with ESMTPA; 5 Apr 2019 13:51:21 -0000 From: Mel Gorman To: Linus Torvalds Cc: Andrew Morton , Linux-MM , LKML , Mel Gorman Subject: [PATCH 2/2] mm/compaction.c: abort search if isolation fails Date: Fri, 5 Apr 2019 14:51:20 +0100 Message-Id: <20190405135120.27532-3-mgorman@techsingularity.net> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190405135120.27532-1-mgorman@techsingularity.net> References: <20190405135120.27532-1-mgorman@techsingularity.net> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Qian Cai Running LTP oom01 in a tight loop or memory stress testing put the system in a low-memory situation could triggers random memory corruption like page flag corruption below due to in fast_isolate_freepages(), if isolation fails, next_search_order() does not abort the search immediately could lead to improper accesses. UBSAN: Undefined behaviour in ./include/linux/mm.h:1195:50 index 7 is out of range for type 'zone [5]' Call Trace: dump_stack+0x62/0x9a ubsan_epilogue+0xd/0x7f __ubsan_handle_out_of_bounds+0x14d/0x192 __isolate_free_page+0x52c/0x600 compaction_alloc+0x886/0x25f0 unmap_and_move+0x37/0x1e70 migrate_pages+0x2ca/0xb20 compact_zone+0x19cb/0x3620 kcompactd_do_work+0x2df/0x680 kcompactd+0x1d8/0x6c0 kthread+0x32c/0x3f0 ret_from_fork+0x35/0x40 ------------[ cut here ]------------ kernel BUG at mm/page_alloc.c:3124! invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI RIP: 0010:__isolate_free_page+0x464/0x600 RSP: 0000:ffff888b9e1af848 EFLAGS: 00010007 RAX: 0000000030000000 RBX: ffff888c39fcf0f8 RCX: 0000000000000000 RDX: 1ffff111873f9e25 RSI: 0000000000000004 RDI: ffffed1173c35ef6 RBP: ffff888b9e1af898 R08: fffffbfff4fc2461 R09: fffffbfff4fc2460 R10: fffffbfff4fc2460 R11: ffffffffa7e12303 R12: 0000000000000008 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000007 FS: 0000000000000000(0000) GS:ffff888ba8e80000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc7abc00000 CR3: 0000000752416004 CR4: 00000000001606a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: compaction_alloc+0x886/0x25f0 unmap_and_move+0x37/0x1e70 migrate_pages+0x2ca/0xb20 compact_zone+0x19cb/0x3620 kcompactd_do_work+0x2df/0x680 kcompactd+0x1d8/0x6c0 kthread+0x32c/0x3f0 ret_from_fork+0x35/0x40 Link: http://lkml.kernel.org/r/20190320192648.52499-1-cai@lca.pw Fixes: dbe2d4e4f12e ("mm, compaction: round-robin the order while searching the free lists for a target") Signed-off-by: Qian Cai Acked-by: Mel Gorman Cc: Daniel Jordan Cc: Mikhail Gavrilov Cc: Vlastimil Babka Cc: Pavel Tatashin Signed-off-by: Mel Gorman --- mm/compaction.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/compaction.c b/mm/compaction.c index b4930bf93c8a..3319e0872d01 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -1370,7 +1370,7 @@ fast_isolate_freepages(struct compact_control *cc) count_compact_events(COMPACTISOLATED, nr_isolated); } else { /* If isolation fails, abort the search */ - order = -1; + order = cc->search_order + 1; page = NULL; } } -- 2.16.4