[systemd-devel] Antw: [EXT] I/O error on "systemctl kill -s HUP rsyslog.service"

[Lennart Poettering]

On Do, 13.08.20 10:05, Andrei Borzenkov (arvidjaar at gmail.com) wrote:

> >>> 1     openat(AT_FDCWD,
> >>> "/sys/fs/cgroup/unified/system.slice/rsyslog.service/cgroup.procs",
> >>> O_RDONLY|O_CLOEXEC) = 24
> >>> 1     read(24, "0\n1544456\n", 4096)    = 10
> >>
> >>
> >> kernel returns "0" as process number in this cgroup which results in EIO
> >> returned by systemd.
> >
>
> systemd should really clearly log this (invalid PID and and in which
> cgroup it was). Returning generic error message without any indication
> what caused this error is not useful at all.

Well, this is an impossible error. We generally trust the kernel to
return valid data. If it doesn't we are fucked, and I am not sure we
have to cater for all such cases. Without kernel behaving correctly we
cannot reasonably operate.

And there *is* logging about this: client side, i.e. the message that
this whole thread was started about.

Lennart

--
Lennart Poettering, Berlin