Launchpad has imported 8 comments from the remote bug at https://bugs.freedesktop.org/show_bug.cgi?id=32765.
If you reply to an imported comment from within Launchpad, your comment will be sent to the remote bug automatically. Read more about Launchpad's inter-bugtracker facilities at https://help.launchpad.net/InterBugTracking. ------------------------------------------------------------------------ On 2011-01-01T01:34:24+00:00 Michael Stone wrote: For the past year, distro bugtrackers have been receiving reports that Xephyr segfaults when it tries to map its client-facing root window: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/635523 https://bugzilla.redhat.com/show_bug.cgi?id=518960 https://qa.mandriva.com/show_bug.cgi?id=47928 The cause of the problem is that, on some 24bpp hosts, this computation: http://cgit.freedesktop.org/xorg/xserver/tree/hw/kdrive/ephyr/ephyr.c#n255 yields a value for priv->bytes_per_line which is too small. priv->bytes_per_line is then used by Xephyr to create its host-side image data buffer (resulting in a buffer that is too small). Then, when Xephyr maps its root window, it segfaults by writing beyond the end of the too-small image data buffer while filling its root window in response to expose-event/damage processing. As for fixes: ajax proposed one fix for this problem six months ago that seems to have gotten lost after an unanswered request for an amendment by keithp: http://patchwork.freedesktop.org/patch/1327/ I tested this patch against Ubuntu's xserver-xorg_2:1.9.0-0ubuntu7 package (from Maverick) and can confirm that it fixed the segfault for me in that environment. Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/7 ------------------------------------------------------------------------ On 2011-04-08T01:38:26+00:00 Dsheil wrote: Still seeing this bug in Ubuntu 11.04 (Natty, not Maverick). The definition of the KdScreenInfo data structure changed between the time of the aforementioned patch and now, so the lines: screen->fb[0].depth screen->fb[0].bitsPerPixel should be: screen->fb.depth screen->fb.bitsPerPixel I believe Keith Packard wanted a more robust patch, with the settings being obtained from the underlying XImage. But my individual need is smaller, and Xephyr is segfaulting for me, so the patch is "good enough for me". I applied the patch (with the modifications I mentioned) and Xephyr is now launching properly. Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/9 ------------------------------------------------------------------------ On 2011-09-18T08:18:18+00:00 Jeremy Huddleston wrote: I think we should just remove Xephyr in 1.12 now that we have xf86 -video-nested Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/11 ------------------------------------------------------------------------ On 2011-09-18T15:29:28+00:00 Julien Cristau wrote: On Sun, Sep 18, 2011 at 01:18:20 -0700, bugzilla-dae...@freedesktop.org wrote: > --- Comment #2 from Jeremy Huddleston <jerem...@freedesktop.org> 2011-09-18 > 01:18:18 PDT --- > I think we should just remove Xephyr in 1.12 now that we have > xf86-video-nested That seems rather premature to me. Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/12 ------------------------------------------------------------------------ On 2011-09-18T19:31:59+00:00 Jeremy Huddleston wrote: Why not? We've been talking about it for 3-4 years now. How long does something need to be unmaintained and bitrot before you decide to move on to its replacement? Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/13 ------------------------------------------------------------------------ On 2011-09-19T06:12:49+00:00 David Ayers wrote: Has xf86-video-nested been packaged and backported to the stable/LTS releases of the major distributions? If not I would agree that closing this issue is premature. Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/14 ------------------------------------------------------------------------ On 2011-09-19T06:33:09+00:00 Jeremy Huddleston wrote: xf86-video-nested is not in the LTS distros, but neither is xserver-1.12. Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/15 ------------------------------------------------------------------------ On 2011-09-19T06:34:58+00:00 Jeremy Huddleston wrote: I'm simply advocating that for 1.12 and onward, we should not advocate use of Xnest, Xvfb, Xfake, and Xephyr and instead advocate use of this alternative. This will allow us to not split our efforts across three products which do the exact same thing going forward. If you want to officially deprecate it in 1.12 and remove it in 1.13, I'm happy with that as well. Reply at: https://bugs.launchpad.net/xorg-server/+bug/635523/comments/16 ** Bug watch added: Red Hat Bugzilla #518960 https://bugzilla.redhat.com/show_bug.cgi?id=518960 ** Bug watch added: Mandriva Linux #47928 http://qa.mandriva.com/show_bug.cgi?id=47928 -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-server in Ubuntu. https://bugs.launchpad.net/bugs/635523 Title: Xephyr crashed with SIGSEGV To manage notifications about this bug go to: https://bugs.launchpad.net/xorg-server/+bug/635523/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
