On Fri, 28 Jun 2024 21:17:26 +0900 Takashi Yano wrote: > Sorry for very late replay. > > On Mon, 3 Jun 2024 15:20:32 +0200 > Johannes Khoshnazar-Thoma wrote: > > We did more testing and it looks like the name of the event > > that signals console master thread start and end is shared between > > unrelated processes (it uses the console minor which is always (?) > > 0 when running from a powershell). > > > > So since it is a two-state event (as opposed to a semaphore) > > in theory the following can happen: > > > > Process A Process B > > SetEvent(e) > > SetEvent(e) > > Waitforevent(e) > > Waitforevent(e) > > This should not happen. Master thread is unique to console. > get_minor() number is always 0 for the first opened console. > If you open another powershell window and start cygwin process > while the first cygwin process is still active, the get_minor() > returns 1. > > Waiting for thread_sync_event is executed only > if (shared_console_info[unit] && con.owner == myself->pid) > con.owner is in the shared memory which is shared among all > processes started in the same console. Therefore, only the > one process start to wait the event. > > > The second SetEvent does nothing. As a result the > > later Waitforevent is stuck (which is what we observe). > > > > So the question is: why should this event be used in > > unrelated cygwin processes? Is there a technical reason > > we don't understand (yet) for doing that (sharing the event). > > > > We patched cygwin to use pseudo random event names (the > > tm_usec field of gettimeofday()) and the stuckness vanished. > > So unless there is a reason for sharing the event between > > cygwin processes this patch should work: > > Do you really confirm that your patch resolves the issue? > If so, the cause might be some kind of race issue.
There was similar bug in cygwin 3.5.1, however, it has been already fixed in 3.5.3. https://cygwin.com/git/?p=newlib-cygwin.git;a=commitdiff;h=fc5e9525453fea7c27b0e13635ae54abaa0db69d I believe your problem is reproducible with 3.5.3. Right? -- Takashi Yano <takashi.y...@nifty.ne.jp> -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
