On Tue, 2014-11-04 at 11:40 +0100, Maciej Wereski wrote: > 04.11.2014 o 10:35 Jussi Laako <[email protected]> wrote: > > > On 3.11.2014 10:52, Maciej Wereski wrote: > >> Since systemd v212 DBUS_SESSION_BUS_ADDRESS is set per user in > >> [email protected]. As long as xserver is pulled by default.target in > >> /usr/lib/systemd/user, it will have DBUS_SESSION_BUS_ADDRES set. > > > > That would be generally bad idea, because it may lead to unexpected > > start of Xserver or inability to run more than one X session with the > > same user. > > > > This kind of stuff should be launched inside session, not as a user > > service (singleton per logged in user, regardless of number of logins). > > > > This is one of the areas were are now trying to clean up in Tizen where > > there is horrible mess between user and session services! > > Well, currently user-session-launch uses PAM and logind to login user. > logind starts [email protected], which pulls default.target, which in turn > pulls dbus.service for user. This has address always set to > /run/user/%U/dbus/user_bus_socket. I haven't seen any other dbus session > instances being run. > > Having this set in one place is better solution, than setting this in > multiple service files, scripts and other environment files. What's more > one bus per user may also has it benefits. In the future, when we'll stop > abusing systemd --user to launch and every session has it's own dbus > session, it'll be easier to change that in one place.
If I interpret the last sentence correctly, you think that it would be a good idea to some day run a separate dbus daemon instance for each session. My gut feeling is that most services that use D-Bus are "user services" by nature, and will likely break in a multi-session environment if there's no bus for the "user scope". There may also be "session services" depending on a "session bus", but I can't name any. If there are both "user services" and "session services", and we need to support multiple session buses running simultaneously, then we will continue have a mess... Perhaps in that case we need two layers of dbus daemons for each user, one for the user bus and N for the session buses, but that sounds messy too... I hope that it will turn out that we will only ever need a single user bus, and there will be no need for separate session buses. -- Tanu _______________________________________________ Dev mailing list [email protected] https://lists.tizen.org/listinfo/dev
