Comment 1 for bug 1663106

Two threads look suspicious during the hang:

Thread 1:

#0 pthread_cond_wait@@GLIBC_2.3.2 ()
    at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1 0x00007f34c8fd2b4b in QWaitCondition::wait(QMutex*, unsigned long) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2 0x00007f34c965dc7b in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#3 0x00007f34c961a0d5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#4 0x00007f34c961a8a5 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#5 0x00007f34c962671d in ?? () from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#6 0x00007f34c9626875 in QDBusInterface::QDBusInterface(QString const&, QString const&, QString const&, QDBusConnection const&, QObject*) ()
   from /usr/lib/x86_64-linux-gnu/libQt5DBus.so.5
#7 0x00007f348291b12b in UCContentHub::UCContentHub(QObject*) ()
   from /usr/lib/x86_64-linux-gnu/libUbuntuToolkit.so.5
#8 0x00007f3482936598 in ?? ()
   from /usr/lib/x86_64-linux-gnu/libUbuntuToolkit.so.5
#9 0x00007f34c9e52ea1 in QQmlType::SingletonInstanceInfo::init(QQmlEngine*) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#10 0x00007f34c9eb04c5 in QV4::QmlTypeWrapper::toVariant() const ()
   from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#11 0x00007f34c9d886e6 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#12 0x00007f34c9d88844 in QV4::ExecutionEngine::toVariant(QV4::Value const&, int, bool) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#13 0x00007f34c9ea83ae in QQmlBinding::write(QQmlPropertyData const&, QV4::Value const&, bool, QFlags<QQmlPropertyPrivate::WriteFlag>) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#14 0x00007f34c9ea94e7 in QQmlBinding::update(QFlags<QQmlPropertyPrivate::WriteFlag>) () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#15 0x00007f34c9eb3035 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#16 0x00007f34c9e3d01e in QQmlComponentPrivate::complete(QQmlEnginePrivate*, QQmlComponentPrivate::ConstructionState*) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#17 0x00007f34c9e3d0e7 in QQmlComponentPrivate::completeCreate() ()
   from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#18 0x00007f34c9e3cf50 in QQmlComponent::create(QQmlContext*) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Qml.so.5
#19 0x00007f34cb97d553 in QQuickView::continueExecute() ()
   from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#20 0x00007f34cb97db1d in QQuickViewPrivate::execute() ()
   from /usr/lib/x86_64-linux-gnu/libQt5Quick.so.5
#21 0x0000556b357e79c5 in ?? ()
#22 0x0000556b357e65b3 in ?? ()
#23 0x0000556b357e26c7 in ?? ()
#24 0x00007f34c85df3f1 in __libc_start_main (main=0x556b357e2600, argc=2,
    argv=0x7ffe95fdf8f8, init=<optimised out>, fini=<optimised out>,
    rtld_fini=<optimised out>, stack_end=0x7ffe95fdf8e8)
    at ../csu/libc-start.c:291
#25 0x0000556b357e2a1a in _start ()

Thread 11:

#0 pthread_cond_wait@@GLIBC_2.3.2 ()
    at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
#1 0x00007f34c8fd2b4b in QWaitCondition::wait(QMutex*, unsigned long) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#2 0x00007f34c8fcba23 in QSemaphore::acquire(int) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#3 0x00007f34c91cd71e in QMetaObject::activate(QObject*, int, int, void**) ()
   from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5
#4 0x00007f34c09a5eb7 in SessionAuthorizer::requestAuthorizationForSession(int const&, bool&) ()
   from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqpa-mirserver.so
#5 0x00007f34c099832f in SessionAuthorizer::connection_is_allowed(miral::ApplicationCredentials const&) ()
   from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqpa-mirserver.so
#6 0x00007f34c06f4c34 in ?? () from /usr/lib/x86_64-linux-gnu/libmiral.so.2
#7 0x00007f34bff899ac in ?? ()
   from /usr/lib/x86_64-linux-gnu/libmirserver.so.43
#8 0x00007f34bff8a4c0 in ?? ()
   from /usr/lib/x86_64-linux-gnu/libmirserver.so.43
#9 0x00007f34bff8a67c in ?? ()
   from /usr/lib/x86_64-linux-gnu/libmirserver.so.43
#10 0x00007f34bffa135b in ?? ()
   from /usr/lib/x86_64-linux-gnu/libmirserver.so.43
#11 0x00007f34bff8912d in ?? ()
   from /usr/lib/x86_64-linux-gnu/libmirserver.so.43
#12 0x00007f34c8c58b2f in ?? () from /usr/lib/x86_64-linux-gnu/libstdc++.so.6
#13 0x00007f34c809f6ca in start_thread (arg=0x7f3499dc3700)
    at pthread_create.c:333
#14 0x00007f34c86c70ff in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:105