From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx194.postini.com [74.125.245.194]) by kanga.kvack.org (Postfix) with SMTP id 8B8726B004D for ; Fri, 23 Mar 2012 06:45:24 -0400 (EDT) Received: by iajr24 with SMTP id r24so5894369iaj.14 for ; Fri, 23 Mar 2012 03:45:23 -0700 (PDT) MIME-Version: 1.0 From: Sasha Levin Date: Fri, 23 Mar 2012 12:45:03 +0200 Message-ID: Subject: mm: hung task (handle_pte_fault) Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Hugh Dickins , Peter Zijlstra , Thomas Gleixner , Ingo Molnar Cc: Pekka Enberg , Dave Jones , linux-mm@kvack.org, "linux-kernel@vger.kernel.org List" Hi guys, During fuzzing using trinity inside a KVM tools guest with latest linux-next, I seem to be getting it hung once in a while, with the following spew: [ 1441.420617] INFO: task trinity:2706 blocked for more than 120 seconds. [ 1441.421894] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 1441.424493] trinity D 0000000000000000 3472 2706 16846 0x00000004 [ 1441.426749] ffff880029dbbb38 0000000000000086 ffff880029dbbae8 ffff880029dbbfd8 [ 1441.428582] 00000000001d45c0 ffff880029dba000 00000000001d45c0 00000000001d45c0 [ 1441.430156] 00000000001d45c0 00000000001d45c0 ffff880029dbbfd8 00000000001d45c0 [ 1441.432371] Call Trace: [ 1441.433042] [] ? file_read_actor+0x1d0/0x1d0 [ 1441.434251] [] schedule+0x24/0x70 [ 1441.435314] [] io_schedule+0x87/0xd0 [ 1441.436357] [] sleep_on_page+0x9/0x10 [ 1441.437442] [] __wait_on_bit+0x57/0x80 [ 1441.438584] [] ? __lock_page_or_retry+0x8f/0xd0 [ 1441.439948] [] wait_on_page_bit+0x6e/0x80 [ 1441.440859] [] ? autoremove_wake_function+0x40/0x40 [ 1441.441700] [] ? up_read+0x1e/0x40 [ 1441.442428] [] __lock_page_or_retry+0xc6/0xd0 [ 1441.443270] [] filemap_fault+0x440/0x4e0 [ 1441.444072] [] __do_fault+0x7f/0x5f0 [ 1441.444829] [] ? add_lock_to_list.clone.18.clone.27+0xd0/0xe0 [ 1441.445886] [] handle_pte_fault+0xf7/0x1e0 [ 1441.446740] [] handle_mm_fault+0x1ce/0x330 [ 1441.447537] [] __get_user_pages+0x14c/0x640 [ 1441.448399] [] ? put_lock_stats.clone.19+0xe/0x40 [ 1441.449288] [] ? __lock_acquired+0x19d/0x270 [ 1441.450164] [] __mlock_vma_pages_range+0x87/0xa0 [ 1441.451127] [] do_mlock_pages+0x89/0x160 [ 1441.451932] [] sys_mlockall+0x111/0x1a0 [ 1441.452761] [] system_call_fastpath+0x1a/0x1f [ 1441.453659] no locks held by trinity/2706. [ 1441.454267] Kernel panic - not syncing: hung_task: blocked tasks According to the logs, it's not the direct result of anything specific happening, so I can't give an exact scenario to reproduce it. It does happen rather often. -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org