Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270315AbUJEQIq (ORCPT ); Tue, 5 Oct 2004 12:08:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270298AbUJEQIq (ORCPT ); Tue, 5 Oct 2004 12:08:46 -0400 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 Subject: Re: Core scsi layer crashes in 2.6.8.1 From: James Bottomley To: Oliver Neukum Cc: Mark Lord , Anton Blanchard , Alan Cox , Linux Kernel Mailing List , SCSI Mailing List In-Reply-To: <200410051801.03677.oliver@neukum.org> References: <1096401785.13936.5.camel@localhost.localdomain> <200410051749.22245.oliver@neukum.org> <1096991666.2064.25.camel@mulgrave> <200410051801.03677.oliver@neukum.org> Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Mailer: Ximian Evolution 1.0.8 (1.0.8-9) Date: 05 Oct 2004 11:07:31 -0500 Message-Id: <1096992458.2173.35.camel@mulgrave> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 858 Lines: 21 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 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/