GNOME Bugzilla – Bug 553305
dbus-launch is needed in gdm.in for assistive technologies to see gdm login GUI
Last modified: 2008-12-08 23:44:41 UTC
In working with Ray Strode and Brian Cameron to debug accessibility issues on the GDM login screen, we discovered that a call to dbus-launch was needed in order for assistive technologies to see the login GUI. A sample patch can be found here: http://src.opensolaris.org/source/xref/jds/spec-files/trunk/patches/gdm-06-dbus.diff Ray and I dug into this pretty hard and couldn't determine the exact cause of the problem. It appears as though something is unexpectedly using D-Bus, though we haven't been able to trace the source. Orca was doing something, but we eliminated that and still saw the issue. In addition, this is for GDM 2.20.x. With newer versions of GDM, this should not be an issue. As such, this is mostly just a bug to have a reference number and I think you can feel free to close it as OBSOLETE or WONTFIX.
Created attachment 119335 [details] [review] better patch to fix this problem After doing some research, it seems that this mainly affects GOK. Without this fix, GOK doesn't startup. The problem is that GOK won't start unless it can get configuration values from GConf, and GConf now depends on D-Bus. This is only a problem when using GDM 2.20 with GNOME 2.23 or later. Attaching a better patch which causes the /usr/sbin/gdm script to launch D-Bus as the gdm user. Since the only programs which need D-Bus run as the "gdm" user there is no need to start dbus-launch with root privilege here.
Also note bug #553505, which causes GOK to fail to startup at login time if the "gdm" user doesn't have a writable $HOME directory. I am not really wanting to put this patch upstream since it isn't really done properly. We shouldn't just be hacking the script to call dbus-launch. If someone wanted to clean up the patch so that the gdm script only calls dbus-launch when the system has a version of GConf that requires D-Bus, then I'd accept that patch upstream.
Note, in recent testing, this problem no longer appears in GNOME 2.24, and GDM works fine without this patch. I think it was something that was showing up in 2.23 beta releases that got resolved otherwise. I'm closing this bug.