From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755769Ab1GAMpo (ORCPT ); Fri, 1 Jul 2011 08:45:44 -0400 Received: from mailservice.tudelft.nl ([130.161.131.5]:50473 "EHLO mailservice.tudelft.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755146Ab1GAMpm (ORCPT ); Fri, 1 Jul 2011 08:45:42 -0400 X-Spam-Flag: NO X-Spam-Score: -22.9 Message-ID: <4E0DC172.9010504@tudelft.nl> Date: Fri, 01 Jul 2011 14:45:38 +0200 From: =?UTF-8?B?w4lyaWMgUGllbA==?= User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.18) Gecko/20110621 Mandriva/3.1.11-1 (2011.0) Thunderbird/3.1.11 MIME-Version: 1.0 To: Alan Stern , Greg KH CC: LKML , "Rafael J. Wysocki" Subject: Regression 3.0-rc5+ : khubd blocked Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, I've come across to what looks like a regression in the kernel a few commits after 3.0-rc5. When I turn off a usb hub, to which my mouse and keyboard are connected, and then turn it on again, they are not detected again. After unplugging it and waiting a few minutes I get a "task khubd:621 blocked for more than 120 seconds." I haven't investigated much. It seems reproducible here on my x86_64 laptop. It doesn't seem to happen on a 3.0-rc4. Maybe important, my kernel already has commit 2e34b429a404675dc4fc4ad2ee339eea028da3ca "Merge branch 'usb-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6" Let me know if you need me to investigate more, or maybe there is already a fix for that bug? Below is the whole message of the hung. Cheers, Éric Jul 1 14:08:16 dutifh kernel: INFO: task khubd:621 blocked for more than 120 seconds. Jul 1 14:08:16 dutifh kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Jul 1 14:08:16 dutifh kernel: khubd D ffff88013a30dfd8 0 621 2 0x00000000 Jul 1 14:08:16 dutifh kernel: ffff88013a30db00 0000000000000046 ffff88013a30da10 ffffffffa00dd852 Jul 1 14:08:16 dutifh kernel: ffff88013b954320 ffff88013a30dfd8 ffff88013a30dfd8 ffff88013a30dfd8 Jul 1 14:08:16 dutifh kernel: ffff88013b891660 ffff88013b954320 ffff8800bb0084c0 dead000000100100 Jul 1 14:08:16 dutifh kernel: Call Trace: Jul 1 14:08:16 dutifh kernel: [] ? usb_hcd_giveback_urb+0x72/0xe0 [usbcore] Jul 1 14:08:16 dutifh kernel: [] ? __rcu_read_unlock+0x2f/0x200 Jul 1 14:08:16 dutifh kernel: [] __mutex_lock_slowpath+0xf4/0x190 Jul 1 14:08:16 dutifh kernel: [] mutex_lock+0x1d/0x40 Jul 1 14:08:16 dutifh kernel: [] usb_set_interface+0x62/0x250 [usbcore] Jul 1 14:08:16 dutifh kernel: [] usb_unbind_interface+0x10f/0x180 [usbcore] Jul 1 14:08:16 dutifh kernel: [] __device_release_driver+0x77/0xd0 Jul 1 14:08:16 dutifh kernel: [] device_release_driver+0x27/0x40 Jul 1 14:08:16 dutifh kernel: [] bus_remove_device+0x73/0xb0 Jul 1 14:08:16 dutifh kernel: [] device_del+0x125/0x1a0 Jul 1 14:08:16 dutifh kernel: [] usb_disable_device+0x7c/0x1a0 [usbcore] Jul 1 14:08:16 dutifh kernel: [] usb_disconnect+0xa0/0x140 [usbcore] Jul 1 14:08:16 dutifh kernel: [] usb_disconnect+0x7c/0x140 [usbcore] Jul 1 14:08:16 dutifh kernel: [] hub_thread+0xa9e/0x1350 [usbcore] Jul 1 14:08:16 dutifh kernel: [] ? abort_exclusive_wait+0xb0/0xb0 Jul 1 14:08:16 dutifh kernel: [] ? usb_remote_wakeup+0x40/0x40 [usbcore] Jul 1 14:08:16 dutifh kernel: [] kthread+0x87/0x90 Jul 1 14:08:16 dutifh kernel: [] kernel_thread_helper+0x4/0x10 Jul 1 14:08:16 dutifh kernel: [] ? kthread_worker_fn+0x190/0x190 Jul 1 14:08:16 dutifh kernel: [] ? gs_change+0x13/0x13