I'm beginning to think this is not a kernel bug, but something caused by some configuration file/change.
This bug persists even when downgrading to two previous kernels, linux-image-3.2.0-2-686-pae_3.2.19-1 linux-image-3.2.0-2-686-pae_3.2.18-1 downloaded from snapshot.debian.org (thanks for pointing it out, Ben Hutchings) The bug is present even when upgrading to linux-image-3.4-trunk-686-pae (from Debian experimental). (Won't install linux-image-3.5 at the moment, apt-get complains about a missing linux-kbuild-3.5) The bug is not present when booting from a live CD (happened to have lying around a 'Gnome 3.0 live DVD, built on openSuse'. (I closed the lid four times -> sleep. ) Searching on "legacy resume(): pnp_bus_resume" I come across a number of (possibly or not, be careful) related reports, involving Thinkpads (X200, X201, T400). For example here, https://bugs.launchpad.net/ubuntu/+source/libcgroup/+bug/838729 one poster reports that the bug disappears when using pm-suspend from the command line. I confirm that I've tried that now six times, without GDM crashing. -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org