From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Brownell Subject: Re: [linux-usb-devel] Re: bug 2400 Date: Tue, 06 Apr 2004 09:16:43 -0700 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <4072D7EB.1010105@pacbell.net> References: <108109222 3.2034.8.camel@mulgrave> <407050F4.2090607@pacbell.net> <1081104161.2112.34.camel@mulgrave> <4070D891.9040409@pacbell.net> <1081201463.2050.92.camel@mulgrave> <4071EA82.3020901@pacbell.net> <1081214360.1756.330.camel@mulgrave> <4072C876.7030906@pacbell.net> <1081266433.1837.29.camel@mulgrave> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mtaw4.prodigy.net ([64.164.98.52]:28818 "EHLO mtaw4.prodigy.net") by vger.kernel.org with ESMTP id S263893AbUDFQQq (ORCPT ); Tue, 6 Apr 2004 12:16:46 -0400 In-Reply-To: <1081266433.1837.29.camel@mulgrave> List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: Alan Stern , Mike Anderson , Andrew Morton , greg@kroah.com, Jens Axboe , linux-usb-devel@lists.sourceforge.net, SCSI Mailing List James Bottomley wrote: >>> that's intra subsystem synchronisation, not inter subsystem >> >>I'd say that device_driver.remove() calls from the bus management >>code to a given device driver are inter-subsystem... > > so using a subsystem provided API from another subsystem constitutes > inter subsytem synchronisation? I don't think so. So it's now "I won't listen to those facts, they bother me" ... Or maybe you're just trolling? "From another subsystem" is "between subsystems" is "inter-subsystem"; Q.E.D. Either way, it's not worth the time to respond to you any more, this will be my last post on this thread. >>Refcounting systems need loop-breaking protocols ("disconnect"); >>this is needed for that sort of reason, if no other. > > > No, they don't. Without protocols for breaking referencing loops, systems that use refcounting _alone_ (as you're advocating) leak memory unless they prevent such loops ... but requests sent from one subsystem to the next, then later returned, each embed such a loop. That's in addition to the need for locking in certain paths, on multi-threaded systems (like Linux). (And for that matter, there were no WMDs in Iraq.) Sorry for mentioning all those inconvenient facts; I'll go away now.