From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx115.postini.com [74.125.245.115]) by kanga.kvack.org (Postfix) with SMTP id C19946B0031 for ; Wed, 17 Jul 2013 20:09:03 -0400 (EDT) Date: Thu, 18 Jul 2013 09:09:01 +0900 From: Minchan Kim Subject: Re: hugepage related lockdep trace. Message-ID: <20130718000901.GA31972@blaptop> References: <20130717153223.GD27731@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130717153223.GD27731@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Dave Jones , Linux Kernel , linux-mm@kvack.org Cc: Rik van Riel , "Aneesh Kumar K.V" , Michal Hocko , KAMEZAWA Hiroyuki , Hillf Danton , Andrew Morton Ccing people get_maintainer says. On Wed, Jul 17, 2013 at 11:32:23AM -0400, Dave Jones wrote: > [128095.470960] ================================= > [128095.471315] [ INFO: inconsistent lock state ] > [128095.471660] 3.11.0-rc1+ #9 Not tainted > [128095.472156] --------------------------------- > [128095.472905] inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. > [128095.473650] kswapd0/49 [HC0[0]:SC0[0]:HE1:SE1] takes: > [128095.474373] (&mapping->i_mmap_mutex){+.+.?.}, at: [] page_referenced+0x87/0x5e3 > [128095.475128] {RECLAIM_FS-ON-W} state was registered at: > [128095.475866] [] mark_held_locks+0x81/0xe7 > [128095.476597] [] lockdep_trace_alloc+0x5e/0xbc > [128095.477322] [] __alloc_pages_nodemask+0x8b/0x9b6 > [128095.478049] [] __get_free_pages+0x20/0x31 > [128095.478769] [] get_zeroed_page+0x12/0x14 > [128095.479477] [] __pmd_alloc+0x1c/0x6b > [128095.480138] [] huge_pmd_share+0x265/0x283 > [128095.480138] [] huge_pte_alloc+0x5d/0x71 > [128095.480138] [] hugetlb_fault+0x7c/0x64a > [128095.480138] [] handle_mm_fault+0x255/0x299 > [128095.480138] [] __do_page_fault+0x142/0x55c > [128095.480138] [] do_page_fault+0xd/0x16 > [128095.480138] [] error_code+0x6c/0x74 > [128095.480138] irq event stamp: 3136917 > [128095.480138] hardirqs last enabled at (3136917): [] _raw_spin_unlock_irq+0x27/0x50 > [128095.480138] hardirqs last disabled at (3136916): [] _raw_spin_lock_irq+0x15/0x78 > [128095.480138] softirqs last enabled at (3136180): [] __do_softirq+0x137/0x30f > [128095.480138] softirqs last disabled at (3136175): [] irq_exit+0xa8/0xaa > [128095.480138] > other info that might help us debug this: > [128095.480138] Possible unsafe locking scenario: > > [128095.480138] CPU0 > [128095.480138] ---- > [128095.480138] lock(&mapping->i_mmap_mutex); > [128095.480138] > [128095.480138] lock(&mapping->i_mmap_mutex); > [128095.480138] > *** DEADLOCK *** > > [128095.480138] no locks held by kswapd0/49. > [128095.480138] > stack backtrace: > [128095.480138] CPU: 1 PID: 49 Comm: kswapd0 Not tainted 3.11.0-rc1+ #9 > [128095.480138] Hardware name: Dell Inc. Precision WorkStation 490 /0DT031, BIOS A08 04/25/2008 > [128095.480138] c1d32630 00000000 ee39fb18 c15b001e ee395780 ee39fb54 c15acdcb c1751845 > [128095.480138] c1751bbf 00000031 00000000 00000000 00000000 00000000 00000001 00000001 > [128095.480138] c1751bbf 00000008 ee395c44 00000100 ee39fb88 c10a6130 00000008 0000d8fb > [128095.480138] Call Trace: > [128095.480138] [] dump_stack+0x4b/0x79 > [128095.480138] [] print_usage_bug+0x1d9/0x1e3 > [128095.480138] [] mark_lock+0x1e0/0x261 > [128095.480138] [] ? check_usage_backwards+0x109/0x109 > [128095.480138] [] __lock_acquire+0x623/0x17f2 > [128095.480138] [] ? sched_clock_cpu+0xcd/0x130 > [128095.480138] [] ? sched_clock_local+0x42/0x12e > [128095.480138] [] lock_acquire+0x7d/0x195 > [128095.480138] [] ? page_referenced+0x87/0x5e3 > [128095.480138] [] mutex_lock_nested+0x6c/0x3a7 > [128095.480138] [] ? page_referenced+0x87/0x5e3 > [128095.480138] [] ? page_referenced+0x87/0x5e3 > [128095.480138] [] ? mem_cgroup_charge_statistics.isra.24+0x61/0x9e > [128095.480138] [] page_referenced+0x87/0x5e3 > [128095.480138] [] ? raid0_congested+0x26/0x8a [raid0] > [128095.480138] [] shrink_page_list+0x3d9/0x947 > [128095.480138] [] ? trace_hardirqs_on+0xb/0xd > [128095.480138] [] shrink_inactive_list+0x155/0x4cb > [128095.480138] [] shrink_lruvec+0x300/0x5ce > [128095.480138] [] shrink_zone+0x53/0x14e > [128095.480138] [] kswapd+0x517/0xa75 > [128095.480138] [] ? mem_cgroup_shrink_node_zone+0x280/0x280 > [128095.480138] [] kthread+0xa8/0xaa > [128095.480138] [] ? trace_hardirqs_on+0xb/0xd > [128095.480138] [] ret_from_kernel_thread+0x1b/0x28 > [128095.480138] [] ? insert_kthread_work+0x63/0x63 IMHO, it's a false positive because i_mmap_mutex was held by kswapd while one in the middle of fault path could be never on kswapd context. It seems lockdep for reclaim-over-fs isn't enough smart to identify between background and direct reclaim. Wait for other's opinion. > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@kvack.org. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: email@kvack.org -- Kind regards, Minchan Kim -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org