From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754904AbZESGrN (ORCPT ); Tue, 19 May 2009 02:47:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752324AbZESGq7 (ORCPT ); Tue, 19 May 2009 02:46:59 -0400 Received: from mtagate3.uk.ibm.com ([195.212.29.136]:59366 "EHLO mtagate3.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751385AbZESGq6 (ORCPT ); Tue, 19 May 2009 02:46:58 -0400 Message-ID: <4A1255E1.1060301@linux.vnet.ibm.com> Date: Tue, 19 May 2009 08:46:57 +0200 From: Stefan Raspl Reply-To: raspl@linux.vnet.ibm.com User-Agent: Thunderbird 2.0.0.12 (X11/20080303) MIME-Version: 1.0 To: Li Zefan CC: linux-btrace@vger.kernel.org, Jens Axboe , linux-kernel@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com Subject: Re: [Patch] blktrace: remove debugfs entries on bad path References: <4A115BA5.6090905@linux.vnet.ibm.com> <4A1207DE.4000409@cn.fujitsu.com> In-Reply-To: <4A1207DE.4000409@cn.fujitsu.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Li Zefan wrote: > A better title: > [Patch] blktrace: remove debugfs entries on bad path > > Stefan Raspl wrote: >> debugfs directory entries for devices are not removed on bad path. > > Can you be more elaborate on how to reproduce this issue? It can happen for most bad pathes within do_blk_trace_setup(). One way to trigger is to set the Vmalloc space via the respective kernel parameter to a value that is so small that it will not suffice for the 2MB per device and cpu that is required. For instance, set vmalloc=10M and start blktrace on a system with 2 cpus on 7 devices. Depending on how much Vmalloc space is still free, the final 2 or 3 devices will fail with a message like this: BLKTRACESETUP(2) /dev/sdu failed: 5/Input/output error Best regards, Stefan Raspl