xserver/hw
Olivier Fourdan 3362422e84 xwayland: remove dirty window unconditionally on unrealize
This is a rare occurrence of a crash in Xwayland for which I don't have
the reproducing steps, just a core file.

The backtrace looks as follow:

  #0  raise () from /usr/lib64/libc.so.6
  #1  abort () from /usr/lib64/libc.so.6
  #2  OsAbort () at utils.c:1361
  #3  AbortServer () at log.c:877
  #4  FatalError () at log.c:1015
  #5  OsSigHandler () at osinit.c:154
  #6  <signal handler called>
  #7  xwl_glamor_pixmap_get_wl_buffer () at xwayland-glamor.c:162
  #8  xwl_screen_post_damage () at xwayland.c:514
  #9  block_handler () at xwayland.c:665
  #10 BlockHandler () at dixutils.c:388
  #11 WaitForSomething () at WaitFor.c:219
  #12 Dispatch () at dispatch.c:422
  #13 dix_main () at main.c:287

The crash is caused by dereferencing “xwl_pixmap->buffer” in
xwl_glamor_pixmap_get_wl_buffer() because “xwl_pixmap” is NULL.

Reason for this is because the corresponding pixmap is from the root
window and xwayland is rootless by default.

This can happen if the window was mapped, redirected, damaged and
unredirected immediately, before the damage is processed by Xwayland.

Make sure to remove the dirty window from the damage list on unrealize
to prevent this from happening.

Credit goes to Adam Jackson <ajax@nwnk.net> and Daniel Stone
<daniel@fooishbar.org> for finding the root cause the issue.

Signed-off-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
2018-01-25 10:31:45 -05:00
..
dmx glx: Drop references to <GL/internal/glcore.h> 2017-11-14 16:18:47 -05:00
kdrive kdrive: remove KdSignalWrapper etc. 2017-12-13 11:11:47 -05:00
vfb test: Add basic SYNC tests. 2017-09-20 13:19:27 -04:00
xfree86 modesetting: setup colormap 2018-01-24 16:17:22 -05:00
xnest Add a Meson build system alongside autotools. 2017-04-26 15:25:27 -07:00
xquartz glx: Fix glXQueryContext for GLX_FBCONFIG_ID and GLX_RENDER_TYPE (v2) 2017-12-01 16:13:18 -05:00
xwayland xwayland: remove dirty window unconditionally on unrealize 2018-01-25 10:31:45 -05:00
xwin meson.build: Fix hw/xwin build when dependencies are installed in a non-default location 2018-01-22 13:50:20 -05:00
Makefile.am Xwayland DDX 2014-04-03 15:19:22 -07:00
meson.build meson: Move Xvfb build under an option. 2017-09-20 13:19:21 -04:00