gdm scans all home directories, makes it impossible to log in if one of them is e.g. on NFS and stalled

[Christian Hudon]

We have a small Ubuntu 10.04 LTS deployment (about 10 seats), with some home directories mounted on NFS. Even with the face chooser disabled, gdm still scans every home directory before allowing someone to log in. If any of the home directories is stalls (because its NFS server is down), then no one can log in, including the users whose home directories are available. Needless to say, this is a really bad failure mode.

The symptoms are really confusing too. Either the computer stays stuck at the plymouth splash screen (because it's waiting for gdm to come up), or when clicking the "log in" button (to get the username text field... this is the lucid gdm), the username text field doesn't come up but the "log In" and "cancel" buttons do.