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Date: Mon, 31 May 2010 11:45:13 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 02/15] qdev: Fix scanning across single-bus
	devices
References: <cover.1274516288.git.jan.kiszka@web.de>	<cover.1274516288.git.jan.kiszka@web.de>	<c375fba941d2c62025d5e60a85d4db2a301e30b1.1274516288.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>, Jan Kiszka <jan.kiszka@siemens.com>, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>, Jan Kiszka <jan.kiszka@web.de>, Avi Kivity <avi@redhat.com>

On 05/29/10 09:38, Markus Armbruster wrote:
> [cc: kraxel]
>
> Jan Kiszka<jan.kiszka@web.de>  writes:
>
>> From: Jan Kiszka<jan.kiszka@siemens.com>
>>
>> As long as we allow /dev.1 as shortcut for /dev1/bus1, we also have to
>> make sure that /dev1/dev2 works for /dev1/bus1/dev2/bus2 - as long as
>> there is only one child bus per device.
>
> We auto-root a path not starting with '/' via convention "first
> component is ID then" (I like that).  We auto-complete a path ending
> with a device when we want a bus (a bit too clever).

... only if there is a single child bus only (i.e. it isn't ambiguous). 
  Which is the common case though.

> Auto-inserting bus
> names in the middle is too clever by half!

Yea.  I have to agree here.  It can only work reliably if you make sure 
all your devices have unique ids.  In which case there is no need to 
reference dev1 at all, you can just use the "first component is ID then" 
mechanism for dev2.

cheers,
   Gerd