Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752631Ab0AUPxi (ORCPT ); Thu, 21 Jan 2010 10:53:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752323Ab0AUPxh (ORCPT ); Thu, 21 Jan 2010 10:53:37 -0500 Received: from mtagate6.uk.ibm.com ([194.196.100.166]:41251 "EHLO mtagate6.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751447Ab0AUPxg (ORCPT ); Thu, 21 Jan 2010 10:53:36 -0500 Date: Thu, 21 Jan 2010 16:53:35 +0100 From: Heiko Carstens To: "Eric W. Biederman" Cc: linux-kernel@vger.kernel.org, Greg KH Subject: [2.6.33-rc4] sysfs lockdep warnings on cpu hotplug Message-ID: <20100121155335.GB4471@osiris.boeblingen.de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2626 Lines: 56 Hi Eric, rumours are that you could be responsible for the following lockdep message: Happens on cpu hotplug on s390: ============================================= [ INFO: possible recursive locking detected ] 2.6.33-rc4-00399-g24bc734 #1 --------------------------------------------- bash/2576 is trying to acquire lock: (s_active){++++.+}, at: [<000000000016c506>] sysfs_addrm_finish+0x5a/0xa8 but task is already holding lock: (s_active){++++.+}, at: [<000000000016c90c>] sysfs_get_active_two+0x64/0x88 other info that might help us debug this: 5 locks held by bash/2576: #0: (&buffer->mutex){+.+.+.}, at: [<000000000016a912>] sysfs_write_file+0x4a/0x1a8 #1: (s_active){++++.+}, at: [<000000000016c90c>] sysfs_get_active_two+0x64/0x88 #2: (s_active){++++.+}, at: [<000000000016c8e6>] sysfs_get_active_two+0x3e/0x88 #3: (cpu_add_remove_lock){+.+.+.}, at: [<00000000003dd318>] cpu_down+0x44/0x88 #4: (cpu_hotplug.lock){+.+.+.}, at: [<0000000000056eee>] cpu_hotplug_begin+0x3e/0x74 stack backtrace: CPU: 1 Not tainted 2.6.33-rc4-00399-g24bc734 #1 Process bash (pid: 2576, task: 000000003f0e25d0, ksp: 000000003d9339d8) 000000003d9338b0 000000003d933830 0000000000000002 0000000000000000 000000003d9338d0 000000003d933848 000000003d933848 00000000003e4996 0000000000000000 0000000000000000 000000003f0e2cb8 0000000000835208 000000000000000d 000000000000000c 000000003d933898 0000000000000000 0000000000000000 00000000000172aa 000000003d933830 000000003d933870 Call Trace: ([<00000000000171b2>] show_trace+0xee/0x144) [<000000000008a1a0>] validate_chain+0xa2c/0x1100 [<000000000008ad84>] __lock_acquire+0x510/0xbfc [<000000000008b51c>] lock_acquire+0xac/0xd4 [<000000000016bba8>] sysfs_deactivate+0x94/0x108 [<000000000016c506>] sysfs_addrm_finish+0x5a/0xa8 [<0000000000169f38>] sysfs_hash_and_remove+0x64/0x9c [<000000000016dbae>] sysfs_remove_group+0x76/0x12c [<00000000003dfaae>] smp_cpu_notify+0xae/0xc8 [<00000000003eb652>] notifier_call_chain+0x56/0x98 [<000000000007a1b2>] raw_notifier_call_chain+0x2a/0x3c [<00000000003dd132>] _cpu_down+0x1aa/0x34c [<00000000003dd356>] cpu_down+0x82/0x88 [<00000000003ddac0>] store_online+0x5c/0xc8 [<000000000016a9be>] sysfs_write_file+0xf6/0x1a8 [<00000000000ffd5c>] vfs_write+0xac/0x178 [<00000000000fff24>] SyS_write+0x58/0xa8 [<00000000000295b6>] sysc_noemu+0x10/0x16 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/