From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mike Anderson Subject: Re: Block timeouts seem not to be working Date: Thu, 11 Sep 2008 08:42:05 -0700 Message-ID: <20080911154205.GA1069@linux.vnet.ibm.com> References: <1221145521.3330.2.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from e2.ny.us.ibm.com ([32.97.182.142]:53952 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752661AbYIKPmL (ORCPT ); Thu, 11 Sep 2008 11:42:11 -0400 Received: from d01relay04.pok.ibm.com (d01relay04.pok.ibm.com [9.56.227.236]) by e2.ny.us.ibm.com (8.13.8/8.13.8) with ESMTP id m8BFg8KQ023724 for ; Thu, 11 Sep 2008 11:42:08 -0400 Received: from d01av02.pok.ibm.com (d01av02.pok.ibm.com [9.56.224.216]) by d01relay04.pok.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id m8BFg8ls226018 for ; Thu, 11 Sep 2008 11:42:08 -0400 Received: from d01av02.pok.ibm.com (loopback [127.0.0.1]) by d01av02.pok.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id m8BFg7n7020112 for ; Thu, 11 Sep 2008 11:42:08 -0400 Content-Disposition: inline In-Reply-To: <1221145521.3330.2.camel@localhost.localdomain> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: Jens Axboe , linux-scsi James Bottomley wrote: > I just noticed this with a rather finickey SAS system I have. It's got > a SATA DVD attached over an expander. Periodically the DVD just hangs > up, so we wait for the timeout and then send a phy reset which clears > it. > > What I'm seeing with the new block timer code is that the timer never > expires. I can dig some more into this, but if you wanted to test it as > well, the timer code is easy to excite. Just throw away one command in > every 128 or so in the queuecommand routine of your favourite HBA > driver. I have not seen the case of the timer never expiring, but will look into other test cases. Mike C and I where seeing timeout issues (host staying in recovery state or list debug bugon's) when running tests with timeouts set to 1 or 2 seconds. We are working with Jens to address this. The issue we where hitting appears related to the scsi_eh / scsi_done completion synchronization. -andmike -- Michael Anderson andmike@linux.vnet.ibm.com