Thank you for your reply. The event gets fired before applicationDidFinishLaunching is: (output of NSLog(@"event: %@", event);) event: NSEvent: type=Kitdefined loc=(0,1440) time=164310.0 flags=0x40 win=0x0 winNum=0 ctxt=0x0 subtype=1 data1=834 data2=0
I moved allow_events = true just before qemu_sem_post(&app_started_sem) and it also works. Hikaru Nishida 2019年10月14日(月) 22:19 Peter Maydell <peter.mayd...@linaro.org>: > On Mon, 14 Oct 2019 at 13:53, <hikaru...@gmail.com> wrote: > > > > From: Hikaru Nishida <hikaru...@gmail.com> > > > > An NSEvent is fired before applicationDidFinishLaunching on macOS > > Catalina. This causes deadlock of iothread_lock by calling > > bool_with_iothread_lock in handleEvent while its already locked. > > This patch prevents to call bool_with_iothread_lock until the > > app_started_sem is released to prevent this deadlock. > > > > Buglink: https://bugs.launchpad.net/qemu/+bug/1847906 > > Signed-off-by: Hikaru Nishida <hikaru...@gmail.com> > > --- > > ui/cocoa.m | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/ui/cocoa.m b/ui/cocoa.m > > index f12e21df6e..f16d341a0a 100644 > > --- a/ui/cocoa.m > > +++ b/ui/cocoa.m > > @@ -134,6 +134,7 @@ > > > > static QemuSemaphore display_init_sem; > > static QemuSemaphore app_started_sem; > > +volatile sig_atomic_t allow_events; > > > > // Utility functions to run specified code block with iothread lock held > > typedef void (^CodeBlock)(void); > > @@ -729,6 +730,9 @@ - (void) handleMonitorInput:(NSEvent *)event > > > > - (bool) handleEvent:(NSEvent *)event > > { > > + if(!allow_events) { > > + return false; > > + } > > return bool_with_iothread_lock(^{ > > return [self handleEventLocked:event]; > > }); > > @@ -1897,6 +1901,7 @@ static void cocoa_display_init(DisplayState *ds, > DisplayOptions *opts) > > /* Tell main thread to go ahead and create the app and enter the > run loop */ > > qemu_sem_post(&display_init_sem); > > qemu_sem_wait(&app_started_sem); > > + allow_events = true; > > COCOA_DEBUG("cocoa_display_init: app start completed\n"); > > If we do use a flag to fix this race, I think it would be > better to set allow_events = true in the > applicationDidFinishLaunching() function before posting > the app_started_sem. Otherwise there's a window after > applicationDidFinishLaunching() returns but before > cocoa_display_init() resumes and sets the flag where we > will unnecessarily drop events. > > Could you try that and check that it still fixes the hang? > > thanks > -- PMM >
