If you spend anytime in #xubuntu-devel (or if you've experienced this issue yourself), you'll knew it isn't much fun. Luckily, I'm happy to report that I think I may have found a fix (at least a fix to avoid the problem). For those of you experiencing the freezing at the login, edit /etc/xdg/xfce4/xinitrc so that the dbus-launch stuff occurs before the screensaver stuff. This should hopefully result in it not hanging on login for you anymore. If it does, let me know and then try adding a sleep 1 statement inbetween dbus-launch stuff and screensaver stuff and see if you can still reproduce it. Be sure to attach your modified xinitirc file when you send me your success or failures. Cheers, Your fearless leader Cody ;] <div class="gmail_quote">---------- Forwarded message ---------- From: Bryce Harrington <<a href="mailto:bryce@canonical.com">bryce@canonical.com</a>> Date: Fri, Jun 20, 2008 at 11:33 PM Subject: libX11/XCB problems in Hardy To: <a href="mailto:ubuntu-devel@lists.ubuntu.com">ubuntu-devel@lists.ubuntu.com</a> A couple fairly subtle but serious issues have come to light in Hardy relating to XCB-enablement in libX11, and I wanted to send this note to notify of a pending change we'll push out once we have a bit more verification. 185311  locking assertion failure, xorg/libsdl (13 dupes)        Particularly afflicting OpenOffice.org users 232364  dbus-launch hangs at session start waiting on socket output in libxcb        Particularly afflicting Xubuntu users Both issues have seemingly been traced to be related to and/or due to the enablement of XCB in libx11.  While we're not 100% certain libxcb is at fault here, in contacting XCB upstream it seems that locking issues are a known issue with the current version and re-architecting work is underway to resolve them. In the interim, for Hardy I'm considering that we should revert XCB in libx11.  I've prepared libx11 debs with XCB disabled for testing purposes at the above bug id's.  If we can get this verified as resolving the issue (and causing no other notable regression), we can decide on putting an SRU through on it. I'm guessing that the new libxcb will not be appropriate for a Hardy SRU, but we should certainly include it for testing in Intrepid. Thanks go to Calc and Cody for their frontline work on the respective issues. Bryce ----- Forwarded message from Barton C Massey <<a href="mailto:bart@cs.pdx.edu">bart@cs.pdx.edu</a>> ----- Date: Fri, 20 Jun 2008 18:06:23 -0700 From: Barton C Massey <<a href="mailto:bart@cs.pdx.edu">bart@cs.pdx.edu</a>> To: Bryce Harrington <<a href="mailto:bryce@canonical.com">bryce@canonical.com</a>> cc: <a href="mailto:cody-somerville@ubuntu.com">cody-somerville@ubuntu.com</a>, <a href="mailto:jamey@cs.pdx.edu">jamey@cs.pdx.edu</a>, <a href="mailto:tripletj@cs.pdx.edu">tripletj@cs.pdx.edu</a> Subject: Re: (X)Ubuntu hang with XCB / dbus-launch X-Spam-Status: No, score=0.5 required=5.0 tests=AWL,EMPTY_MESSAGE autolearn=no        version=3.2.4 Hi Bryce!  Going well.  I've Cc-ed Jamey and Josh, who are the canonical designees for this stuff.  Jamey is biking for a week in the San Juans, and thus completely uncontactable.  I called Josh and we had a long and informative conversation about the state of things. This is almost surely a bug in libXCB or Xlib: calling XOpenDisplay() arguably should never hang you. Jamey and Josh are finishing up "connection handoff" code that completely re-architectes the Xlib / XCB interaction, and may solve this problem and a bunch of others.  They're close to finishing cleaning up this code and shipping it as the next release of Xlib/XCB. In the meantime, Josh will look at this bug and let you know if he sees anything obvious; also, he may ask you to ship experimental bits to some users with the problem and see if things get all better for them. Thanks much for the note.        Bart In message <<a href="mailto:20080620215012.GV9928@bryceharrington.org">20080620215012.GV9928@bryceharrington.org</a>> you wrote: > We've got a bit of an XCB-related deadlocking problem I'm trying to help > Cody with.  Cody is the lead maintainer of Xubuntu, and this particular > bug is afflicting a huge proportion of the Xubuntu users.  I'm hoping > you could either give us some pointers on debugging this, or introduce > us to someone who can help figure it out? > > The issue is that during dbus-launch start up, there is a hang following > the select() call in _xcb_in_read_block().  I've filed a bug in fdo > bugzilla here: > >   <a href="https://bugs.freedesktop.org/show_bug.cgi?id=16420" target="_blank">https://bugs.freedesktop.org/show_bug.cgi?id=16420</a> > > We're not certain that it's a libxcb bug, or an underlying bug that > libxcb just exposes in this particular environment.  Do you have any > advice on what we could do to chase this down (and/or work around it)? ----- End forwarded message ----- -- ubuntu-devel mailing list <a href="mailto:ubuntu-devel@lists.ubuntu.com">ubuntu-devel@lists.ubuntu.com</a> Modify settings or unsubscribe at: <a href="https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel" target="_blank">https://lists.ubuntu.com/mailman/listinfo/ubuntu-devel</a> </div> -- Cody A.W. Somerville Software Engineer Red Cow Marketing & Technologies, Inc. Office: 506-458-1290 Toll Free: 1-877-733-2699 Fax: 506-453-9112 Cell: 506-449-5899 Email: <a href="mailto:cody@redcow.ca">cody@redcow.ca</a> <a href="http://www.redcow.ca">http://www.redcow.ca</a>