From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:33547) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1FLw-0002MK-QU for qemu-devel@nongnu.org; Wed, 07 Sep 2011 06:27:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1R1FLs-0005jP-JH for qemu-devel@nongnu.org; Wed, 07 Sep 2011 06:27:32 -0400 Received: from thoth.sbs.de ([192.35.17.2]:33572) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1R1FLs-0005j6-6l for qemu-devel@nongnu.org; Wed, 07 Sep 2011 06:27:28 -0400 Message-ID: <4E67470B.1090107@siemens.com> Date: Wed, 07 Sep 2011 12:27:23 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <4E5BE735.3090706@us.ibm.com> <4E5BFCF8.3060206@web.de> <4E5C0250.3000807@codemonkey.ws> <4E5E7DFE.8050809@siemens.com> <20110907095051.GM15275@redhat.com> In-Reply-To: <20110907095051.GM15275@redhat.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH 6/6] qdev: Generate IDs for anonymous devices List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gleb Natapov Cc: qemu-devel , Markus Armbruster On 2011-09-07 11:50, Gleb Natapov wrote: > On Wed, Aug 31, 2011 at 08:31:26PM +0200, Jan Kiszka wrote: >> On 2011-08-29 23:19, Anthony Liguori wrote: >>> On 08/29/2011 03:56 PM, Jan Kiszka wrote: >>>> On 2011-08-29 21:23, Anthony Liguori wrote: >>>>> On 08/26/2011 09:48 AM, Jan Kiszka wrote: >>>>>> In order to address devices for that the user forgot or is even unable >>>>>> (no_user) to provide an ID, assign an automatically generated one. Such >>>>>> IDs have the format #, thus are outside the name space availing >>>>>> to users. Don't use them for bus naming to avoid any other user-visible >>>>>> change. >>>>> >>>>> I don't think this is a very nice approach. Why not eliminate anonymous >>>>> devices entirely and use a parent derived name for devices that are not >>>>> created by the user? >>>> >>>> This eliminates anonymous devices completely. So I guess you are asking >>>> for a different naming scheme, something like.child# >>>> e.g.? Well, we would end up with fairly long names when a complete >>>> hierarchy is anonymous. What would be the benefit? >>> >>> No, I'm saying that whenever a device is created, it should be given a >>> non-random name. IOW, the names of these devices should be stable. >>> >>>> I'm really just looking for some simple, temporary workaround without >>>> touching the existing fragile naming scheme. What we really need is full >>>> path addressing, but that without preserving all the legacy. >>> >>> Yeah, I understand, and I hesitated making any grander suggestions here, >>> but I'm not sure how much work it would be to just remove any caller >>> that passes NULL for ID and replace it with something more meaningful. I >>> think that's a helpful clean up long term no matter what. >> >> That won't solve the problem of finding a unique device name. If we want >> to derive it from stable device properties (bus addresses etc.), we >> first of all have to define them for all types of devices. And that's >> basically were the discussion exploded last year IIRC. >> > Why not use the OpenFirmware naming that we already have for some > devices instead of inventing something new? Because I do not want to establish any path names before QOM conversion (including potential device reorganization) has been started. Specifically as I do not need naming for "some" devices, but for all. Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux