https://bugs.kde.org/show_bug.cgi?id=422111
--- Comment #72 from Sam Edwards <cfswo...@gmail.com> --- I tried QDBUS_DEBUG=1; the extra output to the terminal slowed things down enough that the race stopped happening. I had to redirect stderr to a tmpfs-backed file to get the issue to happen again, but apparently redirecting stderr shuts off the other debug logs? I had no luck with getting DBus running over TCP either. The session launched, but *slowly* -- it felt like the session launch kept blocking on something that had to time out before it could continue. Once again, no race condition. I didn't find it worthwhile to dig deeper. The dbus-monitor --pcap worked, though. The messages are all in the expected order - the org.kde.Solid.PowerManagement registration signal arrives after the ListNames reply, despite the respective callbacks firing out of order. The timestamps indicate that the signal is ~32.4 ms after the ListNames request finishes, which is... quite the window, if those timestamps are accurate. I'm not really sure how useful the dbus-monitor results are when DBus itself is a suspect, but I'm thinking we should be pointing the finger at Qt regardless. The single-threaded nature of dbus-daemon means they'd have to be *trying* to introduce message races, and with all of these threads in plasmashell, all it would take for a race there is for the two signals to take paths involving different threads. Perhaps most importantly, most of the earliest reports here are with Qt 5.15.0, which suggests this is a regression that appeared shortly after upgrading to the 5.15 series. I don't understand what you mean about plasma-nm making a blocking call affecting plasmashell - isn't plasma-nm a different process? Wouldn't plasmashell be unaware of other calls into DBus and especially of whether those calls are performed in a blocking/nonblocking manner? Or are you talking about interactions between plasma-nm and plasmashell *via* DBus? Happy to debug the queue replay code if you point me to the file that contains it! :) -- You are receiving this mail because: You are watching all bug changes.
