From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paolo Bonzini Subject: Re: [PATCH] scsi: Add QEMU CD-ROM to VPD Inquiry Blacklist Date: Mon, 6 Jun 2016 18:03:46 +0200 Message-ID: <2e9d3296-3da3-aef0-521c-d096daa37c21@redhat.com> References: <1464702149-26573-1-git-send-email-emilne@redhat.com> <5755278E.8040002@suse.de> <1465222299.20724.114.camel@localhost.localdomain> <5755873E.5080303@suse.de> <4c7c1ec8-06bf-e2f5-c971-de82eb69fdb4@redhat.com> <69fd3238-fde2-90f3-2eb6-3f71a7317016@redhat.com> <92aeeb5e-9b36-339e-8e44-afb78adeac6e@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: Received: from mx1.redhat.com ([209.132.183.28]:10348 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752122AbcFFQDx (ORCPT ); Mon, 6 Jun 2016 12:03:53 -0400 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: John Snow , Hannes Reinecke , emilne@redhat.com Cc: linux-scsi@vger.kernel.org On 06/06/2016 17:47, John Snow wrote: > > > Various downstreams may have backported the VPD fix to older versions, > > > we need to be careful not to block those, too ... so targeting the core > > > behavior seems like the more strictly correct, easily maintainable solution. > > > > I think this is not practical. I'm okay with the big hammer if an > > algorithmic fix is not feasible; but otherwise it does seem a better > > idea than blacklisting based on inquiry data... > > You think the more practical solution is a SCSI driver that can hang > because of an incorrect/missing response and to maintain a carefully > curated blacklist to work around this behavior? The best solution would be an algorithmic fix, perhaps predicated by some kind of quirk bit. A carefully curated blacklist is impossible because you cannot account for a zillion downstreams, most of which probably don't change the inquire vendor/product data; version numbers are awful. Paolo