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From: Markus Armbruster <armbru@redhat.com>
Subject: Re: [Qemu-devel] [PATCH v4 03/23] qdev: Drop ID matching from qtree
	paths
References: <cover.1276641524.git.jan.kiszka@web.de>
	<cover.1276641524.git.jan.kiszka@web.de>
	<fce0e55f5bf02172957365f5674e89a4d64257e4.1276641524.git.jan.kiszka@web.de>
Date: Wed, 23 Jun 2010 10:55:22 +0200
In-Reply-To: <fce0e55f5bf02172957365f5674e89a4d64257e4.1276641524.git.jan.kiszka@web.de>
	(Jan Kiszka's message of "Wed, 16 Jun 2010 00:38:27 +0200")
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To: Jan Kiszka <jan.kiszka@web.de>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Juan Quintela <quintela@redhat.com>, Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>, Blue Swirl <blauwirbel@gmail.com>, Avi Kivity <avi@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>

[cc: kraxel]

Jan Kiszka <jan.kiszka@web.de> writes:

> From: Jan Kiszka <jan.kiszka@siemens.com>
>
> Device IDs may conflict with device names or aliases. From now on we
> only accept them outside qtree paths. This also makes dumping IDs in
> qbus_list_dev/bus obsolete.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>

I don't like this at all.

1. Specific problem:

   With the current code, multiple devices with the same driver work
   only if I take care: addressing by driver name gets me only the
   first, so I better set suitable IDs.

   With your patch, multiple devices with the same driver don't work, no
   matter what I do.

2. General principle:

   When I set an ID, I want the system to accept that ID in all contexts
   where it makes sense.  Ambiguity created by badly chosen IDs is *my*
   problem.