hard hang in 9.99.74

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

I updated to 9.99.74/amd64 from last night to test the bugfix for the NFS
problem in 9.99.73, started a bulk build and went to bed.

In the morning the machine had hung hard, I couldn't even get into
DDB. From the logs it looks like the machine had been up for about 2
hours.

There was a bulk build running and heavy network traffic, mostly NFS.
I see nothing in the logs.

 Thomas