From mboxrd@z Thu Jan  1 00:00:00 1970
From: Markus Armbruster <armbru@redhat.com>
Subject: Re: RFC qdev path semantics
Date: Wed, 16 Jun 2010 15:05:31 +0200
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To: Alex Williamson <alex.williamson@redhat.com>
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In-Reply-To: <m3d3vr48f6.fsf@blackfin.pond.sub.org> (Markus Armbruster's
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Markus Armbruster <armbru@redhat.com> writes:

[...]
> Bus names are chosen by the system as follows:
>
> * If the driver of the parent device model provides a name, use that.
>
> * Else, if the parent device has id ID, use ID.NUM, where NUM is the bus
>   number, counting from zero in creation order.
>
> * Else, use TYPE.NUM, where TYPE is derived from the bus type, and NUM
>   is the bus number, as above.
>
> ### Paul proposes to drop ID.NUM.

ABI change: "-device lsi,id=my-scsi -device scsi-disk,bus=my-scsi.0" no
longer works.

> ### Paul proposes to either drop TYPE.NUM (and require drivers to
>     provide bus names), or make NUM count separately for each bus type.

Likewise.

I'm not saying we can't do this, just that we need to consider backward
compatibility.

[...]