Google has recently published a list of Chromebooks that are affected by the Meltdown vulnerability. They also mention which devices have been patched and also which devices haven’t been patched. They also mark down devices that have reached EoL (end of life) status, meaning that these device will not get the update due to them no longer being supported.
We suppose that is fair and it also pretty much means what EoL is supposed to indicate, so if you see your device on the list that says EoL, then we guess you’ll just need to be extra careful regarding the vulnerability, or purchase a newer and more secure Chromebook. That being said for the most part it seems that Google’s own devices are already protected, so you can rest assured on that front, and to Google’s credit there aren’t that many devices marked as EoL, so hopefully the number of users not covered will be minimal.