Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760053Ab0HLNJb (ORCPT ); Thu, 12 Aug 2010 09:09:31 -0400 Received: from core.signal11.us ([64.251.29.136]:55718 "EHLO core.signal11.us" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760012Ab0HLNJ2 (ORCPT ); Thu, 12 Aug 2010 09:09:28 -0400 Message-ID: <4C63F285.8070801@signal11.us> Date: Thu, 12 Aug 2010 09:09:25 -0400 From: Alan Ott User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.10) Gecko/20100528 Thunderbird/3.0.5 MIME-Version: 1.0 To: Markus Trippelsdorf Cc: Jiri Kosina , Heinz Diehl , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, linux-input@vger.kernel.org, Arnd Bergmann Subject: Re: [BUG] object: is not initialized, yet kobject_put() is being called References: <20100810210941.GA7938@fritha.org> <20100810223215.GA1609@arch.tripp.de> <20100812091659.GA1591@arch.tripp.de> <20100812113624.GB1591@arch.tripp.de> <20100812114513.GA1584@arch.tripp.de> <20100812115657.GA1611@arch.tripp.de> <20100812130411.GA1626@arch.tripp.de> In-Reply-To: <20100812130411.GA1626@arch.tripp.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-DSPAM-Result: Whitelisted X-DSPAM-Processed: Thu Aug 12 09:09:27 2010 X-DSPAM-Confidence: 0.9899 X-DSPAM-Probability: 0.0000 X-DSPAM-Signature: 4c63f287270807514917925 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3822 Lines: 84 On 08/12/2010 09:04 AM, Markus Trippelsdorf wrote: > On Thu, Aug 12, 2010 at 02:57:57PM +0200, Jiri Kosina wrote: > >> On Thu, 12 Aug 2010, Jiri Kosina wrote: >> >> >>>>>>>>> Guys, could you please send me your .config with which you are >>>>>>>>> experiencing the problem, so that I can try to reproduce it with it? >>>>>>>>> >>>>>>>> Attached. >>>>>>>> >>>>>>> So I had to add support for HW of mine (SATA_VIA, PATA_VIA, disabled the >>>>>>> radeon firmware stuff, and, most importantly, enabled UHCI, which is what >>>>>>> is on machine I am using now for testing), and disconnect-connect cycle >>>>>>> works nicely: >>>>>>> >>>>>>> usb 3-2: USB disconnect, address 3 >>>>>>> usb 3-2: new low speed USB device using uhci_hcd and address 4 >>>>>>> input: mouse USB mouse with wheel as /devices/pci0000:00/0000:00:10.1/usb3/3-2/3-2:1.0/input/input6 >>>>>>> generic-usb 0003:05B8:3091.0004: input,hidraw0: USB HID v1.10 Mouse [mouse USB mouse with wheel] on usb-0000:00:10.1-2/input0 >>>>>>> input: mouse USB mouse with wheel as /devices/pci0000:00/0000:00:10.1/usb3/3-2/3-2:1.1/input/input7 >>>>>>> generic-usb 0003:05B8:3091.0005: input,hidraw1: USB HID v1.10 Keyboard [mouse USB mouse with wheel] on usb-0000:00:10.1-2/input1 >>>>>>> >>>>>>> so still no BUG from kobject refcounting, and the hidraw numbers are the >>>>>>> same. The major difference seems to be that I am using UHCI and you have >>>>>>> your HID devices connected through OHCI, is that correct? >>>>>>> >>>>>> Correct. And I should add that it very easy to reproduce here; just >>>>>> disconnecting the usb receiver triggers the WARNING. >>>>>> >>>>> Disabling USB_HIDDEV in my .config solves the problem (there is no >>>>> WARNING anymore when disconnecting the receiver). >>>>> >>>> Reverting bd25f4dd6972755579d0ea50d1a5ace2e9b00d1a with USB_HIDDEV >>>> enabled also solves the problem. So there must be a bug in that patch: >>>> >>>> commit bd25f4dd6972755579d0ea50d1a5ace2e9b00d1a >>>> Author: Arnd Bergmann >>>> Date: Sun Jul 11 15:34:05 2010 +0200 >>>> >>>> HID: hiddev: use usb_find_interface, get rid of BKL >>>> >>>> This removes the private hiddev_table in the usbhid >>>> driver and changes it to use usb_find_interface >>>> instead. >>>> >>>> The advantage is that we can avoid the race between >>>> usb_register_dev and usb_open and no longer need the >>>> big kernel lock. >>>> >>>> This doesn't introduce race condition -- the intf pointer could be >>>> invalidated only in hiddev_disconnect() through usb_deregister_dev(), >>>> but that will block on minor_rwsem and not actually remove the device >>>> until usb_open(). >>>> >>>> Signed-off-by: Arnd Bergmann >>>> Cc: Jiri Kosina >>>> Cc: "Greg Kroah-Hartman" >>>> Signed-off-by: Jiri Kosina >>>> >>> Thanks, I had my suspicion about this commit (that's why I asked to you >>> verify with CONFIG_USB_HIDDEV turned off as well). >>> >>> Adding Arnd to CC and will look into it myself as well soon. >>> >>> Arnd, the complete thread can be found at >>> http://lkml.org/lkml/2010/8/10/280 >>> >> Could please those of you, who are able to reproduce the problem, verify >> whether the patch below (completely untested) makes everything behave >> again? Thanks. >> > Yes, everything behaves again. Thanks Jiri. > Seconded. Works good. Thanks for your support Jiri. -- 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/