On Fri, 07.11.14 20:59, Alexandre Detiste (alexandre.deti...@gmail.com) wrote:
> Hi, > > I know that generators should log to /dev/kmsg during early boot. Correct! > But, when they are restarted later by systemcl daemon-reload; > is it better to write to the journal instead, by using systemd-cat for > example ? > Or is it racy/forbidden ? Yes, this is dangerous. During a "daemon-reload" PID 1 serilizes its state to a file in /run, then flushes all configuration, then invokes the generators, and then rereads the configuration and deserializes the state. Now, if you generator accesses the journal socket, and journald is not running yet (because you are in emergency mode for example), then things might deadlock: as logging is synchronous and the socket buffer is limited in size your generator might block while writing the log message and since activation cannot take place as PID 1 is not processing any events while doing the whole state flush/config flush/generator magic/config reload/state reload it would never unblock again. Generators really really shouldn't talk to any other services, and this means for logging they should log to /dev/kmsg or suchlike. Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel
