openmoko-today becomes blank screen

[erin_yueh@…]

1. press 2nd tab from Openmoko-today, click any one UI application, eg 'Contacts'
2. press upper left area 'Contacts' and then choose 'Home'
3. press 3rd tab from Openmoko-today, click 'Contacts' couple times
4. if you find the title from 'Home' and becomes to 'Your operator name' in

upper left area

5. Returns to Openmoko-today, it becomes WHITE screen.

[thomas@…]

I can reproduce this bug. It seems to get stuck in some kind of loop, which
prevents the application from being redrawn. This is why you see a white screen.

[thomas@…]

So far the only stack trace I have is not very helpful:

0x407a6294 in read () from /lib/libpthread.so.0
(gdb) bt
#0 0x407a6294 in read () from /lib/libpthread.so.0
#1 0x407a6284 in read () from /lib/libpthread.so.0
Backtrace stopped: previous frame identical to this frame (corrupt stack?)

[thomas@…]

I've reproduced the bug on my desktop machine and can get these two stack traces
when stopping the process. It's using 100% CPU, so I imagine there is some kind
of loop going on.

(gdb) bt
#0 0xb73d0ac1 in ?? () from /usr/lib/libX11.so.6
#1 0xbfdd0158 in ?? ()
#2 0xb73d0cab in _XReply () from /usr/lib/libX11.so.6
#3 0xb73c275f in XQueryTree () from /usr/lib/libX11.so.6
#4 0xb7f93244 in moko_finger_scroll_get_topmost (window=0x863d580, x=139,

y=11, tx=0xbfdd0278, ty=0xbfdd0274) at moko-finger-scroll.c:131

#5 0xb7f939ce in moko_finger_scroll_button_press_cb (scroll=0x8460178,

event=0x84a39a8, user_data=0x0) at moko-finger-scroll.c:260

#6 0xb7a1e344 in _gtk_marshal_BOOLEANBOXED (closure=0x8464728,

return_value=0xbfdd04b0, n_param_values=2, param_values=0xbfdd0594,
invocation_hint=0xbfdd049c, marshal_data=0xb7f93710)
at /tmp/buildd/gtk+2.0-2.12.9/gtk/gtkmarshalers.c:84

#7 0xb769c6f9 in g_closure_invoke () from /usr/lib/libgobject-2.0.so.0
#8 0xb76b0c3d in ?? () from /usr/lib/libgobject-2.0.so.0

#0 0xb769ef30 in g_object_weak_unref () from /usr/lib/libgobject-2.0.so.0
#1 0xb769f033 in g_object_remove_weak_pointer ()

from /usr/lib/libgobject-2.0.so.0

#2 0xb7af5454 in gtk_tooltip_set_last_window (tooltip=0x863d5e0,

window=0x8484b94) at /tmp/buildd/gtk+2.0-2.12.9/gtk/gtktooltip.c:719

#3 0xb7af5d17 in _gtk_tooltip_handle_event (event=0x84a3a48)

at /tmp/buildd/gtk+2.0-2.12.9/gtk/gtktooltip.c:1185

#4 0xb7a1878a in IAgtk_main_do_event (event=0x84a3a48)

at /tmp/buildd/gtk+2.0-2.12.9/gtk/gtkmain.c:1608

#5 0xb78845ba in gdk_event_dispatch (source=0x8081ca8, callback=0,

user_data=0x0) at /tmp/buildd/gtk+2.0-2.12.9/gdk/x11/gdkevents-x11.c:2351

#6 0xb761b7e8 in g_main_context_dispatch () from /usr/lib/libglib-2.0.so.0
#7 0xb761ea3e in ?? () from /usr/lib/libglib-2.0.so.0
#8 0x08081cf0 in ?? ()
#9 0x00000000 in ?? ()

[chris@…]

Fixed in r4318 of libmokoui2:

• libmokoui/moko-finger-scroll.c (moko_finger_scroll_button_press_cb), (moko_finger_scroll_motion_notify_cb), (moko_finger_scroll_button_release_cb): Don't bother checking the last event type when detecting infinite loops, it just causes problems with double-clicking

[erin_yueh@…]

Chris, thanks!