Ed noticed in  bug 748115  that chromeos-login includes a post-stop upstart script which uses the "-u" flag to sudo. On some boards (e.g., many that inherit the embedded profile), sudo is provided by a script that just wraps 'su', and doesn't handle this properly. Altogether, this can yield a system that sits in a loop at reboot, failing to progress due to command failures.

Many boards resolve this problem by either forcing on USE='pam' (which pulls in a proper 'sudo'), or else prunes out any ebuild that might bring in chromeos-login (e.g., debugd).

Per Mike's suggestion, we should probably either improve the fake 'sudo', or just install the real one.

A quick check shows that the sudo/su wrapper only takes 658 bytes, vs. a typical sudo binary is over 92KB (plus libraries, and other tools like visudo). Don't know if any embedded builds are worried about a few hundred KB.