From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:38702) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QKZaa-0001ZM-TN for qemu-devel@nongnu.org; Thu, 12 May 2011 13:22:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QKZaZ-0003yV-RP for qemu-devel@nongnu.org; Thu, 12 May 2011 13:22:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36204) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QKZaZ-0003yP-Eg for qemu-devel@nongnu.org; Thu, 12 May 2011 13:22:15 -0400 Date: Thu, 12 May 2011 14:22:05 -0300 From: Luiz Capitulino Message-ID: <20110512142205.52c60ed4@doriath> In-Reply-To: References: <1305212715-26767-1-git-send-email-armbru@redhat.com> <1305212715-26767-4-git-send-email-armbru@redhat.com> <20110512140143.1ffb7eeb@doriath> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 3/6] block QMP: Drop query-block member "type" (type= in info block) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Markus Armbruster Cc: kwolf@redhat.com, hch@lst.de, qemu-devel@nongnu.org, kraxel@redhat.com On Thu, 12 May 2011 19:12:56 +0200 Markus Armbruster wrote: > Luiz Capitulino writes: > > > On Thu, 12 May 2011 17:05:12 +0200 > > Markus Armbruster wrote: > > > >> Its value is unreliable: a block device used as floppy has type > >> "floppy" if created with if=floppy, but type "hd" if created with > >> if=none. > >> > >> That's because with if=none, the type is at best a declaration of > >> intent: the drive can be connected to any guest device. Its type is > >> really the guest device's business. Reporting it here is wrong. > > > > It reports how the guest is using the device, right? I'd say that's what > > users/clients are interested in knowing. > > The value is *unreliable*. It may or may not match how the guest is > using the device. I doubt users are interested in unreliable > information. Can't it be fixed? And how are users/clients supposed to find out how the guest is using its block devices? > > Also, we can't just drop it from QMP. We should first note it's deprecated. > > Would you accept a change to the more honest value "unknown" for the > deprecation period? We have to avoid breaking the protocol. Changing something that has always been reported as 'cdrom' to 'unknown' will likely cause as many as damages as dropping the command. The best solution I can think of is noting in the documentation that the information is unreliable and explain what clients interested in knowing this info should do.