From mboxrd@z Thu Jan 1 00:00:00 1970 From: Erik Andersen Subject: Re: [PATCH] SCSI hotplug support Date: Mon, 14 Oct 2002 14:41:22 -0600 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20021014204122.GB24904@codepoet.org> References: <20021014054035.GA10686@codepoet.org> <20021014000602.F30278@one-eyed-alien.net> <20021014071252.GB13512@codepoet.org> <20021014154719.GE21010@nbkurt.casa-etp.nl> <20021014161922.GB2940@beaverton.ibm.com> Reply-To: andersen@codepoet.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20021014161922.GB2940@beaverton.ibm.com> List-Id: linux-scsi@vger.kernel.org To: Kurt Garloff , Linux SCSI list , USB Storage List On Mon Oct 14, 2002 at 09:19:22AM -0700, Mike Anderson wrote: > Kurt Garloff [garloff@suse.de] wrote: > > There are some scary comments around the scsi add/remove-single-device > > code which imply that this stuff only works by accident. > > I have used this functionality heavily for some time now and have never > > had a problem. Same for people I talked to. > > But it would probably make sense to review the code for possible > > problems. > > > > But I'm all for integrating your patch. It does not introduce new > > problems. And if it exposes old ones, because the code is more > > heavily used, this can only be good. > > The comments may be pointing at the issues of the locking around the > host_queue. Adds will probably be ok as we init the scsi_device before It was my understanding that the comments (which were present long before I changed anything) refer mainly to the fact that hotswapping with a normal SCSI subsystem (without additional electronic support for hotswapping) is electrically unsafe and is likely to fry up your drives and your SCSI host controller. For people with hotswap safe hardware (or using ieee1394 or usb mass storage devices), hotswapping is perfectly normal and safe, and the scarry comments do not apply. -Erik -- Erik B. Andersen http://codepoet-consulting.com/ --This message was written using 73% post-consumer electrons--