Comment 7 for bug 684875

Though a compromise solution would be to register as sda only if the unplug of the original sda device succeeded / is going to be tried. Otherwise it's just going to cause a kernel bug.

I think xen_unplug_emulated_devices() is called sufficiently early you could choose the name when the driver is init'ed, so something like the attached patch (completely untested, may not even compile).

But even so, if you rename the xen block device, you will be running /dev/sdX with a non-standard block major and block minor number (you are not changing the block major / minor numbers). I can't help but think that's a recipe for disaster.