aa9536a992
We used to rely on the order in which the weston_compositor::destroy_signal callbacks happened, to not access freed memory. Don't know when, but this broke at least with ivi-shell, which caused crashes in random places on compositor shutdown. Valgrind found the following: Invalid write of size 8 at 0xC2EDC69: unbind_input_panel (input-panel-ivi.c:340) by 0x4E3B6BB: destroy_resource (wayland-server.c:537) by 0x4E3E085: for_each_helper.isra.0 (wayland-util.c:359) by 0x4E3E60D: wl_map_for_each (wayland-util.c:365) by 0x4E3BEC7: wl_client_destroy (wayland-server.c:675) by 0x4182F2: text_backend_notifier_destroy (text-backend.c:1047) by 0x4084FB: wl_signal_emit (wayland-server-core.h:264) by 0x4084FB: main (compositor.c:5465) Address 0x67ea360 is 208 bytes inside a block of size 232 free'd at 0x4C2A6BC: free (vg_replace_malloc.c:473) by 0x4084FB: wl_signal_emit (wayland-server-core.h:264) by 0x4084FB: main (compositor.c:5465) Invalid write of size 8 at 0x4E3E0D7: wl_list_remove (wayland-util.c:57) by 0xC2EDEE9: destroy_input_panel_surface (input-panel-ivi.c:191) by 0x4E3B6BB: destroy_resource (wayland-server.c:537) by 0x4E3BC7B: wl_resource_destroy (wayland-server.c:550) by 0x40DB8B: wl_signal_emit (wayland-server-core.h:264) by 0x40DB8B: weston_surface_destroy (compositor.c:1883) by 0x40DB8B: weston_surface_destroy (compositor.c:1873) by 0x4E3B6BB: destroy_resource (wayland-server.c:537) by 0x4E3E085: for_each_helper.isra.0 (wayland-util.c:359) by 0x4E3E60D: wl_map_for_each (wayland-util.c:365) by 0x4E3BEC7: wl_client_destroy (wayland-server.c:675) by 0x4182F2: text_backend_notifier_destroy (text-backend.c:1047) by 0x4084FB: wl_signal_emit (wayland-server-core.h:264) by 0x4084FB: main (compositor.c:5465) Address 0x67ea370 is 224 bytes inside a block of size 232 free'd at 0x4C2A6BC: free (vg_replace_malloc.c:473) by 0x4084FB: wl_signal_emit (wayland-server-core.h:264) by 0x4084FB: main (compositor.c:5465) Invalid write of size 8 at 0x4E3E0E7: wl_list_remove (wayland-util.c:58) by 0xC2EDEE9: destroy_input_panel_surface (input-panel-ivi.c:191) by 0x4E3B6BB: destroy_resource (wayland-server.c:537) by 0x4E3BC7B: wl_resource_destroy (wayland-server.c:550) by 0x40DB8B: wl_signal_emit (wayland-server-core.h:264) by 0x40DB8B: weston_surface_destroy (compositor.c:1883) by 0x40DB8B: weston_surface_destroy (compositor.c:1873) by 0x4E3B6BB: destroy_resource (wayland-server.c:537) by 0x4E3E085: for_each_helper.isra.0 (wayland-util.c:359) by 0x4E3E60D: wl_map_for_each (wayland-util.c:365) by 0x4E3BEC7: wl_client_destroy (wayland-server.c:675) by 0x4182F2: text_backend_notifier_destroy (text-backend.c:1047) by 0x4084FB: wl_signal_emit (wayland-server-core.h:264) by 0x4084FB: main (compositor.c:5465) Address 0x67ea368 is 216 bytes inside a block of size 232 free'd at 0x4C2A6BC: free (vg_replace_malloc.c:473) by 0x4084FB: wl_signal_emit (wayland-server-core.h:264) by 0x4084FB: main (compositor.c:5465) Looking at the first of these, unbind_input_panel() gets called when the text-backend destroys its helper client which has bound to input_panel interface. This happens after the shell's destroy_signal callback has been called, so the shell has already been freed. The other two errors come from wl_list_remove(&input_panel_surface->link); which has gone stale when the shell was destroyed (shell->input_panel.surfaces list). Rather than creating even more destroy listeners and hooking them up in spaghetti, modify text-backend to not hook up to the compositor destroy signal. Instead, make it the text_backend_init() callers' responsibility to also call text_backend_destroy() appropriately, before the shell goes away. This fixed all the above Valgrind errors, and avoid a crash with ivi-shell when exiting Weston. Also using desktop-shell exhibited similar Valgrind errors which are fixed by this patch, but those didn't happen to cause any crashes AFAIK. Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk> Reviewed-By: Derek Foreman <derekf@osg.samsung.com> |
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clients | ||
data | ||
desktop-shell | ||
fullscreen-shell | ||
ivi-shell | ||
m4 | ||
man | ||
protocol | ||
shared | ||
src | ||
tests | ||
wcap | ||
xwayland | ||
.gitignore | ||
autogen.sh | ||
configure.ac | ||
COPYING | ||
Makefile.am | ||
notes.txt | ||
README | ||
releasing.txt | ||
weston.ini.in |
Weston Weston is the reference implementation of a Wayland compositor, and a useful compositor in its own right. Weston has various backends that lets it run on Linux kernel modesetting and evdev input as well as under X11. Weston ships with a few example clients, from simple clients that demonstrate certain aspects of the protocol to more complete clients and a simplistic toolkit. There is also a quite capable terminal emulator (weston-terminal) and an toy/example desktop shell. Finally, weston also provides integration with the Xorg server and can pull X clients into the Wayland desktop and act as a X window manager. Refer to http://wayland.freedesktop.org/building.html for building weston and its dependencies. The test suite can be invoked via `make check`; see http://wayland.freedesktop.org/testing.html for additional details.