From mboxrd@z Thu Jan 1 00:00:00 1970 From: Patrick Mansfield Subject: Re: Patches for SCSI scanning Date: Tue, 20 Apr 2004 10:44:08 -0700 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20040420104408.B8602@beaverton.ibm.com> References: <20040418185751.GC4868@tpkurt.garloff.de> <1082330192.1969.37.camel@mulgrave> <20040420115419.GG4356@tpkurt.garloff.de> <1082471881.1804.34.camel@mulgrave> <20040420092650.A7749@beaverton.ibm.com> <20040420164238.GT4356@tpkurt.garloff.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from e1.ny.us.ibm.com ([32.97.182.101]:24514 "EHLO e1.ny.us.ibm.com") by vger.kernel.org with ESMTP id S263348AbUDTRoz (ORCPT ); Tue, 20 Apr 2004 13:44:55 -0400 Content-Disposition: inline In-Reply-To: <20040420164238.GT4356@tpkurt.garloff.de>; from garloff@suse.de on Tue, Apr 20, 2004 at 06:42:38PM +0200 List-Id: linux-scsi@vger.kernel.org To: Kurt Garloff , James Bottomley , Andrew Morton , Linux SCSI list On Tue, Apr 20, 2004 at 06:42:38PM +0200, Kurt Garloff wrote: > Hi Patrick, > > On Tue, Apr 20, 2004 at 09:26:51AM -0700, Patrick Mansfield wrote: > > On Tue, Apr 20, 2004 at 09:38:00AM -0500, James Bottomley wrote: > > > Yes, sounds reasonable. We can do it all with the boot flags now. > > > > max_scsi_luns should default to zero to avoid devices that should be black > > listed as single lun. > > I strongly disagree. There were some posts in the past by either Alan or Doug L on this, I can't find them. Redhat ships with CONFIG_SCSI_MULTI_LUN not set. > The target should be to blacklist broken devices not working ones. I agree that is where we would like to be, but that can break current usage. > Devices that have multiple LUNs are not, devices that have only one but > report severals are. > > With max_scsi_luns=1, we would need to "black"list every single multi lun > device. I very much dislike that idea. Not individually, just boot with max_scsi_luns=128 or whatever as is done today for redhat, or boot with default_dev_flags=0x040 (BLIST_SPARSELUN). > Fortunately, distributors don't do this. Suse doesn't, Redhat does, I don't know about others. > > So how can you remove those and maintain compatibilty? The removal should > > wait for 2.7. > > Expecting your multi lun devices to work with max_scsi_luns=1 is just > wrong. max_scsi_luns should not default to 1. > Anyways, BLIST_SPARSELUN will have the side-effect of also working > around that misconfiguration. Again that is not compatible with the current 2.6.x code, users with non-black listed single lun devices will get failures if we default to max_scsi_luns > 1. -- Patrick Mansfield