Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933285AbYBMRee (ORCPT ); Wed, 13 Feb 2008 12:34:34 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765914AbYBMReG (ORCPT ); Wed, 13 Feb 2008 12:34:06 -0500 Received: from accolon.hansenpartnership.com ([76.243.235.52]:47385 "EHLO accolon.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759962AbYBMReD (ORCPT ); Wed, 13 Feb 2008 12:34:03 -0500 Subject: Re: [BUGFIX 2/2] gdth: bugfix for the Timer at exit crash From: James Bottomley To: Boaz Harrosh Cc: Sven =?ISO-8859-1?Q?K=F6hler?= , Christoph Hellwig , Jeff Garzik , linux-scsi , linux-kernel@vger.kernel.org, Joerg Dorchain , Jon Chelton , Stefan Priebe - allied internet ag In-Reply-To: <47B32680.5020405@panasas.com> References: <47A19E26.30107@panasas.com> <47B1D7A8.8010108@panasas.com> <47B1DA2A.1060904@panasas.com> <1202917468.3109.5.camel@localhost.localdomain> <47B312B3.3010200@panasas.com> <47B31BDE.2030408@panasas.com> <1202921122.3109.31.camel@localhost.localdomain> <47B31FC2.4040206@panasas.com> <1202922226.3109.36.camel@localhost.localdomain> <47B32680.5020405@panasas.com> Content-Type: text/plain Date: Wed, 13 Feb 2008 11:33:55 -0600 Message-Id: <1202924035.3109.48.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.12.3 (2.12.3-1.fc8) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1906 Lines: 48 On Wed, 2008-02-13 at 19:18 +0200, Boaz Harrosh wrote: > On Wed, Feb 13 2008 at 19:03 +0200, James Bottomley wrote: > > It needs to register a reboot notifier, which gdth does. > > > > However, the notifier is only called on reboot, so it also needs to > > clean up correctly on module exit as well. > > > > The alternative for GDTH would be to process the SCSI SYNCHRONIZE CACHE > > Why would we think that the controller does not support this command > is it not in the mandatory section of the standard? Um, because the controller isn't a SCSI device. It's an emulated device which means the SCSI comands are processed in the driver. It does look like the driver<->HBA communication is some sort of translated dialect of SCSI. > > command. That's done by a shutdown notifier from sd, so the correct > > thing would always get done; however it does mean the driver has to be > > in a condition to process the last sync cache command. > > Why would it not be ready? what do other drivers do? > The drivers is ready until the very last module's .exit. Is that good > enough? shutdown is called as part of device removal and module unload ... usually from scsi_remove_host(). So you can't tear down command processing before that point. > > > > For the quick fix, just keep the current infrastructure and put back the > > gdth_flush() command where it can be effective. > > > > Just did. But if needed I would prefer to emulate the SCSI SYNCHRONIZE CACHE > command and not that boot notifier thing. Please advise. I think such a change, though desirable, would be too large to count as a bug fix. James -- 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/