From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965668AbXC1S4l (ORCPT ); Wed, 28 Mar 2007 14:56:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965671AbXC1S4l (ORCPT ); Wed, 28 Mar 2007 14:56:41 -0400 Received: from nf-out-0910.google.com ([64.233.182.187]:57692 "EHLO nf-out-0910.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965668AbXC1S4k (ORCPT ); Wed, 28 Mar 2007 14:56:40 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:date:from:to:cc:subject:message-id:references:mime-version:content-type:content-disposition:in-reply-to:user-agent; b=qY9n31eFc0y7g+VXLUGRSvv2gQFN/FP6ThCOoH3VYzSrBC2roiMDYFymc9CrWV7TelIUKEa4L+Po56g4v0jEg5yCsEqfqGtywpuVvnOA0XF1ETSfbBcVRIYMgTMNpE+UG2ep4pX5TvDv3ehOE77Ha8ifwKWqyHvPDvDt3bYMiwc= Date: Wed, 28 Mar 2007 22:56:32 +0400 From: Alexey Dobriyan To: Andreas Mohr Cc: Andrew Morton , Greg KH , linux-kernel@vger.kernel.org Subject: Re: tty OOPS (Re: 2.6.21-rc5-mm2) Message-ID: <20070328185632.GB5306@martell.zuzino.mipt.ru> References: <20070326211627.c681af3b.akpm@linux-foundation.org> <20070328170214.GA13044@rhlx01.hs-esslingen.de> <20070328173310.GA4682@rhlx01.hs-esslingen.de> <20070328174524.GA25709@rhlx01.hs-esslingen.de> <20070328180446.GA7528@rhlx01.hs-esslingen.de> <20070328183814.GA5306@martell.zuzino.mipt.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070328183814.GA5306@martell.zuzino.mipt.ru> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 28, 2007 at 10:38:14PM +0400, Alexey Dobriyan wrote: > On Wed, Mar 28, 2007 at 08:04:46PM +0200, Andreas Mohr wrote: > > [unrelated maintainers removed, Alexey added] > > > > On Wed, Mar 28, 2007 at 07:45:24PM +0200, Andreas Mohr wrote: > > > Hi, > > > > > > just wanted to add that when analyzing the backtrace I found the comment > > > at drivers/char/vt.c/con_close() to be VERY suspicious... > > > (need to take tty_mutex to prevent concurrent thread tty access). > > > This might just be what happened here despite trying to protect against it. > > > > OK, can we assume that one of > > > > +protect-tty-drivers-list-with-tty_mutex.patch > > +tty-minor-merge-correction.patch > > +tty-in-tiocsctty-when-we-steal-a-tty-hang-it-up-fix.patch > > > > is responsible / not implemented fully? > > #2 is just comment removal. > > I may state the obvious, but __iget() in sysfs_drop_dentry() gets NULL > inode and you aren't failing on spin_lock one line above because of UP > without spinlock debugging. The only suspicious new patch in -rc5-mm1 to me is fix-sysfs-reclaim-crash.patch which removes "sd->s_dentry = NULL;". Note that whole sysfs_drop_dentry() is NOP if ->s_dentry is NULL. Could you try to revert it? Alexey, who knows very little about sysfs internals