VFS deadlock suspected in -CURRENT

Hi all,

Last night's -CURRENT appears to have demonstrated deadlock. My experience
in this area is extremely limited so I have been trying to track down the
problem with kan's help.

It manifested itself as being unable to log into the machine directly (via
serial console, *or* sshd) due to processes hanging in the VFS locking code,
specifically vfs_lookup.c.

I will let you know more when I have more hard data.

Regards,
BMS