I just started a downsizing resize2fs operation over an SSH session without screen and then realised how bad an idea that was..
Then found this bug as a confirmation. :-) It looks like resize2fs (still) doesn't install any signal handlers so I've just disabled auto-suspend on my laptop and will hope for the best. tytso@ mentions the danger of -M by the way, I guess that danger applies to *any* downsizing operation, not just to bare-minimum resizes done by -M?
