For temporary, I would use "-l" (as in lower-case L) instead of "-f". Don't trust me too much, but flasher takes the same options as the flasher on the computer, so -f would be flash (as in actually write the data to flash chip) and -l would be load (as in load kernel into memory). You can always also type "flasher -h" and "flasher --help" for some basic info on the options.