From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH 4/4] sd: Handle ZBC drives correctly Date: Mon, 21 Jul 2014 19:49:17 +0200 Message-ID: <53CD529D.4050504@suse.de> References: <1405931241-92015-1-git-send-email-hare@suse.de> <1405931241-92015-5-git-send-email-hare@suse.de> <20140721112904.GB15455@infradead.org>,<53CCFEBE.8080400@suse.de> <8A51900D08212F40B3DE22453052F69839C47278@wdscexmb02> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from cantor2.suse.de ([195.135.220.15]:55878 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932647AbaGURt3 (ORCPT ); Mon, 21 Jul 2014 13:49:29 -0400 In-Reply-To: <8A51900D08212F40B3DE22453052F69839C47278@wdscexmb02> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: John Utz , Christoph Hellwig Cc: "linux-ide@vger.kernel.org" , "linux-scsi@vger.kernel.org" , James Bottomely On 07/21/2014 06:18 PM, John Utz wrote: > If I read Hanne's patch correctly, he is checking for the ZBC signatu= re > when the drives are probed. > Yep. > Thus, the only circumstance where adding zbc handling would lead to > unexpected bad behavior in sd would be if a ZBC drive reported itsel= f > as a standard ATA drive or an ATA drive reported itself as a ZBC dri= ve. It's actually worse than that: Currently libata will happily attach to a ZAC device, and passing them=20 on to the SCSI stack as a normal disk device. Which most definitely will lead to unexpected results :-) Cheers, Hannes --=20 Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: J. Hawn, J. Guild, F. Imend=F6rffer, HRB 16746 (AG N=FCrnberg)