"Device busy" errors from rm -rf

[Alan Barrett <apb%cequrux.com@localhost>]

I am running rsync from one disk to another, to make a backup.
At the same time, I am running "rm -rf" to delete an old backup
on the target disk.

The "rm -rf" process gets lots of "Device busy" errors, and fails
to delete everything.  For example:

rm: 20070824/home/apb/netbsd/current/xsrc/Makefile: Device busy
rm: 20070824/home/apb/netbsd/current/xsrc/CVS: Device busy
rm: 20070824/home/apb/netbsd/current/xsrc/dist: Device busy
rm: 20070824/home/apb/netbsd/current/xsrc/local: Device busy
rm: 20070824/home/apb/netbsd/current/xsrc/xfree: Device busy
rm: 20070824/home/apb/netbsd/current/xsrc/xorg: Device busy
rm: 20070824/home/apb/netbsd/current/xsrc: Directory not empty

I am running a 4.99.63 kernel from sources dated 2008-05-24.

Is this likely to be fixed in a newer kernel?  I can't run anything
newer than 2008-06-01 due to the problem in PR 38959.

--apb (Alan Barrett)