From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Bottomley Subject: Re: Core scsi layer crashes in 2.6.8.1 Date: 05 Oct 2004 11:07:31 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1096992458.2173.35.camel@mulgrave> References: <1096401785.13936.5.camel@localhost.localdomain> <200410051749.22245.oliver@neukum.org> <1096991666.2064.25.camel@mulgrave> <200410051801.03677.oliver@neukum.org> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from stat16.steeleye.com ([209.192.50.48]:52915 "EHLO hancock.sc.steeleye.com") by vger.kernel.org with ESMTP id S270445AbUJEQHq (ORCPT ); Tue, 5 Oct 2004 12:07:46 -0400 In-Reply-To: <200410051801.03677.oliver@neukum.org> List-Id: linux-scsi@vger.kernel.org To: Oliver Neukum Cc: Mark Lord , Anton Blanchard , Alan Cox , Linux Kernel Mailing List , SCSI Mailing List On Tue, 2004-10-05 at 11:01, Oliver Neukum wrote: > Why is it in any way difficult to decide whether to issue a command in the > first place? The command is generated upon being notified by the lower layer. > There is no issue of synchronisation here. It is simply stupid to give > commands that are bound to fail, if the information is already available. a) we don't know that they are ... for notified ejection they will succeed. b) The scsi bus is a scanned model ... drivers must be prepared to accept commands for non-existent devices. How does the removal case differ from the never present case? James