From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f53.google.com (mail-pb0-f53.google.com [209.85.160.53]) by kanga.kvack.org (Postfix) with ESMTP id 7E5FE6B003A for ; Wed, 25 Sep 2013 21:48:18 -0400 (EDT) Received: by mail-pb0-f53.google.com with SMTP id up15so432791pbc.26 for ; Wed, 25 Sep 2013 18:48:18 -0700 (PDT) Message-ID: <52439258.3010904@oracle.com> Date: Thu, 26 Sep 2013 09:48:08 +0800 From: Bob Liu MIME-Version: 1.0 Subject: Re: [munlock] BUG: Bad page map in process killall5 pte:cf17e720 pmd:05a22067 References: <20130926004028.GB9394@localhost> In-Reply-To: <20130926004028.GB9394@localhost> Content-Type: multipart/mixed; boundary="------------070901040104010602020109" Sender: owner-linux-mm@kvack.org List-ID: To: Fengguang Wu Cc: Vlastimil Babka , linux-mm@kvack.org, linux-kernel@vger.kernel.org This is a multi-part message in MIME format. --------------070901040104010602020109 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Hi Fengguang, Would you please have a try with the attached patch? It added a small fix based on Vlastimil's patch. Thanks, -Bob On 09/26/2013 08:40 AM, Fengguang Wu wrote: > Hi Vlastimil, > > FYI, this bug seems still not fixed in linux-next 20130925. > > commit 7a8010cd36273ff5f6fea5201ef9232f30cebbd9 > Author: Vlastimil Babka > Date: Wed Sep 11 14:22:35 2013 -0700 > > mm: munlock: manual pte walk in fast path instead of follow_page_mask() > > Currently munlock_vma_pages_range() calls follow_page_mask() to obtain > each individual struct page. This entails repeated full page table > translations and page table lock taken for each page separately. > > This patch avoids the costly follow_page_mask() where possible, by > iterating over ptes within single pmd under single page table lock. The > first pte is obtained by get_locked_pte() for non-THP page acquired by the > initial follow_page_mask(). The rest of the on-stack pagevec for munlock > is filled up using pte_walk as long as pte_present() and vm_normal_page() > are sufficient to obtain the struct page. > > After this patch, a 14% speedup was measured for munlocking a 56GB large > memory area with THP disabled. > > Signed-off-by: Vlastimil Babka > Cc: Jorn Engel > Cc: Mel Gorman > Cc: Michel Lespinasse > Cc: Hugh Dickins > Cc: Rik van Riel > Cc: Johannes Weiner > Cc: Michal Hocko > Cc: Vlastimil Babka > Signed-off-by: Andrew Morton > Signed-off-by: Linus Torvalds > > > [ 89.835504] init: plymouth-upstart-bridge main process (3556) terminated with status 1 > [ 89.986606] init: tty6 main process (3529) killed by TERM signal > [ 91.414086] BUG: Bad page map in process killall5 pte:cf17e720 pmd:05a22067 > [ 91.416626] addr:bfc00000 vm_flags:00100173 anon_vma:cf128c80 mapping: (null) index:bfff0 > [ 91.419402] CPU: 0 PID: 3574 Comm: killall5 Not tainted 3.12.0-rc1-00010-g5fbc0a6 #24 > [ 91.422171] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 > [ 91.423998] 00000000 00000000 c0199e34 c1db5db4 00000000 c0199e54 c10e72d4 000bfff0 > [ 91.427933] 00000000 bfc00000 00000000 000cf17e cf17e720 c0199e74 c10e7995 00000000 > [ 91.431940] bfc00000 cf1ca190 bfc00000 cf180000 cf1ca190 c0199ee0 c10eb8cf ce6d1900 > [ 91.435894] Call Trace: > [ 91.436969] [] dump_stack+0x4b/0x66 > [ 91.438503] [] print_bad_pte+0x14b/0x162 > [ 91.440204] [] vm_normal_page+0x67/0x9b > [ 91.441811] [] munlock_vma_pages_range+0xf9/0x176 > [ 91.443633] [] exit_mmap+0x86/0xf7 > [ 91.445156] [] ? lock_release+0x169/0x1ef > [ 91.446795] [] ? rcu_read_unlock+0x17/0x23 > [ 91.448465] [] ? exit_aio+0x2b/0x6c > [ 91.449990] [] mmput+0x6a/0xcb > [ 91.451508] [] do_exit+0x362/0x8be > [ 91.453013] [] ? hrtimer_debug_hint+0xd/0xd > [ 91.454700] [] do_group_exit+0x51/0x9e > [ 91.456296] [] SyS_exit_group+0x16/0x16 > [ 91.457901] [] sysenter_do_call+0x12/0x33 > [ 91.459553] Disabling lock debugging due to kernel taint > > git bisect start 272b98c6455f00884f0350f775c5342358ebb73f v3.11 -- > git bisect good 57d730924d5cc2c3e280af16a9306587c3a511db # 02:21 495+ Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip > git bisect good 3bb22ec53e2bd12a241ed84359bffd591a40ab87 # 12:03 495+ staging/lustre/ptlrpc: convert to new shrinker API > git bisect bad a5b7c87f92076352dbff2fe0423ec255e1c9a71b # 12:18 31- vmscan, memcg: do softlimit reclaim also for targeted reclaim > git bisect good 3d94ea51c1d8db6f41268a9d2aea5f5771e9a8d3 # 15:40 495+ ocfs2: clean up dead code in ocfs2_acl_from_xattr() > git bisect bad d62a201f24cba74e2fbf9f6f7af86ff5f5e276fc # 16:46 79- checkpatch: enforce sane perl version > git bisect good 83467efbdb7948146581a56cbd683a22a0684bbb # 01:29 585+ mm: migrate: check movability of hugepage in unmap_and_move_huge_page() > git bisect bad 2bff24a3707093c435ab3241c47dcdb5f16e432b # 02:07 148- memcg: fix multiple large threshold notifications > git bisect bad 1ecfd533f4c528b0b4cc5bc115c4c47f0b5e4828 # 02:34 64- mm/mremap.c: call pud_free() after fail calling pmd_alloc() > git bisect good 0ec3b74c7f5599c8a4d2b33d430a5470af26ebf6 # 13:10 1170+ mm: putback_lru_page: remove unnecessary call to page_lru_base_type() > git bisect good 5b40998ae35cf64561868370e6c9f3d3e94b6bf7 # 16:52 1170+ mm: munlock: remove redundant get_page/put_page pair on the fast path > git bisect bad 187320932dcece9c4b93f38f56d1f888bd5c325f # 17:11 0- mm/sparse: introduce alloc_usemap_and_memmap > git bisect bad 6e543d5780e36ff5ee56c44d7e2e30db3457a7ed # 17:29 2- mm: vmscan: fix do_try_to_free_pages() livelock > git bisect bad 7a8010cd36273ff5f6fea5201ef9232f30cebbd9 # 17:59 14- mm: munlock: manual pte walk in fast path instead of follow_page_mask() > git bisect good 5b40998ae35cf64561868370e6c9f3d3e94b6bf7 # 22:10 3510+ mm: munlock: remove redundant get_page/put_page pair on the fast path > git bisect bad 5fbc0a6263a147cde905affbfb6622c26684344f # 22:10 0- Merge remote-tracking branch 'pinctrl/for-next' into kbuild_tmp > git bisect good 87e37036dcf96eb73a8627524be8b722bd1ac526 # 04:31 3510+ Revert "mm: munlock: manual pte walk in fast path instead of follow_page_mask()" > git bisect bad 22356f447ceb8d97a4885792e7d9e4607f712e1b # 04:40 48- mm: Place preemption point in do_mlockall() loop > git bisect bad 050f4da86e9bdbcc9e11789e0f291aafa57b8a20 # 04:55 133- Add linux-next specific files for 20130925 > > Thanks, > Fengguang > --------------070901040104010602020109 Content-Type: text/x-patch; name="0001-mm-munlock-Prevent-walking-off-the-end-of-a-pagetabl.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename*0="0001-mm-munlock-Prevent-walking-off-the-end-of-a-pagetabl.pa"; filename*1="tch" --------------070901040104010602020109--