Hyper-V has an abstract bus, which gets renumbered on guest
startup. So instead of the bus numbers we should be using
the device GUIDs, which can be retrieved from the 'device_id'
sysfs attribute.
Enrico Scholz <enrico.scholz@sigma-chemnitz.de>
>
> E.g. I have a platform with two sdhci controllers with different purposes.
> First slot is an external slot while second one is internal with a
> non-removable card.
>
> When there is a card in the external slot at boot, the non-removable card is
> named 'mmcblk1'; without the external card it is 'mmcblk0'. Vice versa for the
> external card.
https://bugs.freedesktop.org/show_bug.cgi?id=52309