I don't think the fabrics device does not help us to keep the ctrl
allocated until we finish removal.
All fabrics drivers grab an extra reference during ->create_ctrl,
which we will drop when releasing the file descriptor that we used
to create the device.
By the time we call ->delete_ctrl in nvmf_create_ctrl we must still
have that reference because we are still in a ->write call and thus
->release can't have been called yet.
Thanks for the clarification. Is it worth a preparatory patch to
change that before the ctrl device integration for change log
clarity?