From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932186AbYGUDHa (ORCPT ); Sun, 20 Jul 2008 23:07:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759045AbYGUDHU (ORCPT ); Sun, 20 Jul 2008 23:07:20 -0400 Received: from mail.windriver.com ([147.11.1.11]:54318 "EHLO mail.wrs.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759759AbYGUDHT convert rfc822-to-8bit (ORCPT ); Sun, 20 Jul 2008 23:07:19 -0400 Subject: Re: [PATCH]: libata-scsi: Don't start hotplug work queue if hotplug is disabled From: Chunbo Luo Reply-To: chunbo.luo@windriver.com To: Tejun Heo Cc: linux-kernel@vger.kernel.org, jeff@garzik.org, Andrew Morton In-Reply-To: <48809BA0.8060500@kernel.org> References: <1214533246.6284.10.camel@pek-cluo> <48809BA0.8060500@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Organization: Wind River Date: Mon, 21 Jul 2008 11:03:05 +0800 Message-Id: <1216609385.6358.14.camel@pek-cluo> Mime-Version: 1.0 X-Mailer: Evolution 2.22.2 X-OriginalArrivalTime: 21 Jul 2008 03:05:07.0129 (UTC) FILETIME=[9445A290:01C8EADE] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2008-07-18 at 22:33 +0900, Tejun Heo wrote: > Chunbo Luo wrote: > > Hi > > > > When ata_scsi_scan_host() scan device failed, it will start a work queue > > unconditionally. This may cause some noisy messages. This patch fix this > > problem. > > ATA_PFLAG_SCSI_HOTPLUG doesn't mean that hotplug is enabled. It > indicates that EH needs to schedule a kick at SCSI's ass and make it > scan for discovered devices && work running on ata_aux_wq testing it > doesn't mean anything. There's no synchronization. > > > Previously, queue_delayed_work() was started unconditionally, but if > > ATA_PFLAG_SCSI_HOTPLUG is not set and we do this, the work queue may > > cause multiple messages like this: > > > > ata3.00: WARNING: ATAPI is not supported with this driver, device ignored. > > And this message has nothing to do with SCSI. It's printed by libata > proper for several drivers which don't support ATAPI. Did the patch > really kill the warning messages? Can you please post full boot log > from 2.6.26 w/o the patch? If the drivers don't support ATAPI, the hotplug task cannot find linked device, and it will start the hotplug task again. Which will print messages continously like this. ---------- ata3.00: WARNING: ATAPI is not supported with this driver, device ignored. ata3.00: WARNING: ATAPI is not supported with this driver, device ignored. ata3.00: WARNING: ATAPI is not supported with this driver, device ignored. ata3.00: WARNING: ATAPI is not supported with this driver, device ignored. ... ------------ We should find a way to avoid this kind of noisy warning messages. This patch cannot kill the warning messages, but it can avoid the duplicate warning messages. > > Andrew, please drop the patch from -mm. Thanks. >