From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id 5E044B6F1F for ; Fri, 10 Jul 2009 18:35:33 +1000 (EST) Received: from e28smtp06.in.ibm.com (e28smtp06.in.ibm.com [59.145.155.6]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e28smtp06.in.ibm.com", Issuer "Equifax" (verified OK)) by ozlabs.org (Postfix) with ESMTPS id 645DBDDDE9 for ; Fri, 10 Jul 2009 18:35:31 +1000 (EST) Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by e28smtp06.in.ibm.com (8.13.1/8.13.1) with ESMTP id n6A8ZKTl029102 for ; Fri, 10 Jul 2009 14:05:20 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v9.2) with ESMTP id n6A8ZJgn1806562 for ; Fri, 10 Jul 2009 14:05:19 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.13.1/8.13.3) with ESMTP id n6A8ZJba020921 for ; Fri, 10 Jul 2009 18:35:19 +1000 Message-ID: <4A56FD45.6060304@in.ibm.com> Date: Fri, 10 Jul 2009 14:05:17 +0530 From: Sachin Sant MIME-Version: 1.0 To: Alan Cox Subject: Re: Badness at drivers/char/tty_ldisc.c:210 during shutdown References: <4A3A2D2B.7070704@in.ibm.com> <4A3F281F.9000408@in.ibm.com> <1245655421.4400.78.camel@concordia> <20090622095245.38edafdd@lxorguk.ukuu.org.uk> In-Reply-To: <20090622095245.38edafdd@lxorguk.ukuu.org.uk> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-dev@ozlabs.org, linux-kernel List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Alan Cox wrote: >>> [c00000003cf6ba70] [c00000000040a3d0] .tty_ldisc_put+0xa4/0xf4 (unreliable) >>> [c00000003cf6bb10] [c00000000040a7c8] .tty_ldisc_reinit+0x38/0x80 >>> [c00000003cf6bba0] [c00000000040b1d8] .tty_ldisc_hangup+0x190/0x260 >>> [c00000003cf6bc40] [c000000000401090] .do_tty_hangup+0x188/0x4c0 >>> [c00000003cf6bd20] [c000000000401440] .tty_vhangup_self+0x34/0x54 >>> [c00000003cf6bdb0] [c00000000019236c] .sys_vhangup+0x38/0x58 >>> [c00000003cf6be30] [c000000000008534] syscall_exit+0x0/0x40 >>> Instruction dump: >>> 912b0088 4bcd17bd 60000000 e87e8008 7f44d378 481c04fd 60000000 801b0008 >>> 7c09fe70 7d200278 7c004850 54000ffe <0b000000> 7f63db78 4bd7c98d 60000000 >>> >> Ah right, so this has check has just gone in, and the code in question >> has been rewritten somewhat just recently. >> > > The check is to catch any cases where a line discipline is being freed up > but has a refcount that is non zero. I think I know what is going on here. > This issue can be recreated with 2.6.31-rc2-git4 kernel (34f25476ace556263784ea2f8173e22b25557a13). Thanks -Sachin -- --------------------------------- Sachin Sant IBM Linux Technology Center India Systems and Technology Labs Bangalore, India ---------------------------------