From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anton Blanchard Subject: Re: [PATCH] serialize bus scanning Date: Mon, 15 Sep 2003 17:13:05 +1000 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20030915071305.GA820@krispykreme> References: <20030825122416.GE15506@lst.de> <20030827202908.GB7852@krispykreme> <20030827203544.GA27020@lst.de> <20030910075741.GC1532@krispykreme> <20030911133419.A10316@beaverton.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from dp.samba.org ([66.70.73.150]:57064 "EHLO lists.samba.org") by vger.kernel.org with ESMTP id S262461AbTIOHRI (ORCPT ); Mon, 15 Sep 2003 03:17:08 -0400 Content-Disposition: inline In-Reply-To: <20030911133419.A10316@beaverton.ibm.com> List-Id: linux-scsi@vger.kernel.org To: Patrick Mansfield Cc: Christoph Hellwig , James Bottomley , linux-scsi@vger.kernel.org Hi Pat, > The patch looks fine to me, I hope James will apply it. Good to see someone else does parallel scan :) > I think we might still have to allow only a scan or delete (per host), and > not both in parallel - it looks like we could have some races otherwise, > I'm not sure though (mainly where the driver model points to the parent > device). Maybe a get of the host device during scanning is enough. Speaking of races... Ive been tripping one when parallel probing. I hit a poisoned list pointer in scsi_run_host_queues, which is being called out of the error handler thread. (Ive got a few scsi buses in this machine full of bad disks) I havent had a chance to look into it but Im guessing we are racing with someone calling scsi_free_sdev. Im not sure how we should be protecting ->siblings but it looks like we have to do something. Anton