When rpc.statd starts up in user space at boot time, it attempts to
write the latest NSM local state number into
/proc/sys/fs/nfs/nsm_local_state.

If lockd.ko isn't loaded yet (as is the case in most configurations),
that file doesn't exist, thus the kernel's NSM state remains set to
its initial value of zero during lockd operation.

This is a problem because rpc.statd and lockd use the NSM state number
to prevent repeated lock recovery on rebooted hosts.  If lockd sends
a zero NSM state, but then a delayed SM_NOTIFY with a real NSM state
number is received, there is no way for lockd or rpc.statd to
distinguish that stale SM_NOTIFY from an actual reboot.  Thus lock
recovery could be performed after the rebooted host has already
started reclaiming locks, and those locks will be lost.

We could change /etc/init.d/nfslock so it always modprobes lockd.ko
before starting rpc.statd.  However, if lockd.ko is ever unloaded
and reloaded, we are back at square one, since...