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Date: Wed, 23 Jun 2010 12:17:55 +0200
From: Jan Kiszka <jan.kiszka@siemens.com>
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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>
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To: Markus Armbruster <armbru@redhat.com>
Cc: Anthony Liguori <aliguori@us.ibm.com>, Juan Quintela <quintela@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, Luiz Capitulino <lcapitulino@redhat.com>, Blue Swirl <blauwirbel@gmail.com>, Jan Kiszka <jan.kiszka@web.de>, Avi Kivity <avi@redhat.com>, Gerd Hoffmann <kraxel@redhat.com>

Markus Armbruster wrote:
> [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.

[ you already found how this is resolved ]

> 
> 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.

I disagree. IMO, QEMU should support the user to avoid such subtle
shadowing.

Jan

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