Bug#729907: logind fails to create sessions when running on a kernel without cgroups support

[intrigeri]

Control: retitle -1 logind should report clearer error messages when the kernel doesn't support cgroups

Hi Emilio,

Emilio Pozuelo Monfort wrote (18 Nov 2013 19:43:14 GMT) :
> As you can see on bug #729674 and #729877, when running with a kernel without
> cgroup support, CreateSession() fails on logind. The problem is that logind
> looks for /proc/$pid/cgroup, which is missing (though /proc/$pid exists) and it
> confusingly returns ESRCH.

> I don't know if logind requires a kernel with cgroups to create sessions, but if
> that's not possible, at least a better error message would be nice, or maybe
> logind should check for this at init and exit.

/usr/share/doc/systemd/README.gz makes it clear that the kernel must
support cgroups, so this behaviour is expected. Now, I agree that it
would be nice if logind (and friends) reported clearer errors whenever
a needed kernel feature is missing. Retitling accordingly.

Next step for anyone interested is to check if things have improved
upstream in this area since v215, and if not, to check if there's
a ticket in their bug tracker.

Cheers,
--
intrigeri