[Qemu-devel] qemu-img behavior for locating backing files

[John Snow]

Kevin, what's the correct behavior for qemu-img and relative paths when 
creating a new qcow2 file?

Example:

(in e.g. /home/qemu/build/ or anywhere not /home: )
qemu-img create -f qcow2 base.qcow2 32G
qemu-img create -f qcow2 -F qcow2 -b base.qcow2 /home/overlay.qcow2

In 1.7.0., this produces a warning that the base object cannot be found 
(because it does not exist at that location relative to overlay.qcow2), 
but qemu-img will create the qcow2 for you regardless.

2.0, 2.1 and 2.2 all will create the image successfully, with no warnings.

2.3-rc1/master as they exist now will emit an error message and create 
no image.

Since this is a change in behavior for the pending release, is this the 
correct/desired behavior?