From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60457) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WsTik-0006pl-KB for qemu-devel@nongnu.org; Thu, 05 Jun 2014 05:12:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WsTie-0003zS-DK for qemu-devel@nongnu.org; Thu, 05 Jun 2014 05:12:26 -0400 Received: from isrv.corpit.ru ([86.62.121.231]:43754) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WsTie-0003wJ-5I for qemu-devel@nongnu.org; Thu, 05 Jun 2014 05:12:20 -0400 Message-ID: <53903469.8070902@msgid.tls.msk.ru> Date: Thu, 05 Jun 2014 13:12:09 +0400 From: Michael Tokarev MIME-Version: 1.0 References: <1401889659-24035-1-git-send-email-pl@kamp.de> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] block/iscsi: use 16 byte CDBs only when necessary List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: ronnie sahlberg , Peter Lieven Cc: Kevin Wolf , Paolo Bonzini , qemu-devel , Stefan Hajnoczi 04.06.2014 18:00, ronnie sahlberg wrote: > That would mean you get to use the 10 version of the cdb even for very > large devices (as long as the IO is for blocks at the beginning of the > device) and thus provide partial avoidance of this issue for those > large devices. That may make some bugs "ghosty", so to say. Ie, if there's a bug in/with 16 version of a command, you'll hit it only when you actually try to access a "far" area of a drive. Which means you're unlikely to hit it while trying to reproduce in a clean environment, even after using a large device. Or, the bug will be triggered at random, since data placement on the filesystem is effectively (from user PoV) random. To my taste it is better to make it a bit more deterministic. Thanks, /mjt