The helper function _nvme_connect_subsys() creates a nvme device. It may take some time after the function call until the device gets ready for I/O. So it is expected that the test cases call _find_nvme_dev() after _nvme_connect_subsys() before I/O. _find_nvme_dev() returns the path of the created device, and it also waits for uuid and wwid sysfs attributes of the created device get ready. This wait works as the wait for the device I/O readiness.
Shouldn't this call udevadm --settle or something?
