ERROR: The effective user ID of staprun must be set to the root user.

[Jim Keniston <jkenisto at us dot ibm dot com>]

I'm running 2.6.28 with yesterday's utrace bits, today's stap bits, and
elfutils 0.138.  When I run a stap script as a non-root member of group
stapdev (e.g., the "Hello, world" script shown here), upon completion of
the run, staprun reports:
ERROR: The effective user ID of staprun must be set to the root user.
  Check permissions on staprun and ensure it is a setuid root program.
and apparently fails to unload the stap-generated module.

I get no such message if I run stap as root.

stap -vvv reveals that staprun is /usr/local/bin/staprun, which is
indeed a setuid root program.

I built and installed stap as I always have:
./configure --with-elfutils=/.../elfutils-0.138
make
su -
make install

Note that the script runs to completion before I get the error message.

Any suggestions?

Thanks.
Jim
-----
[jimk@xxx stap]$ stap -v hi.stp
Pass 1: parsed user script and 48 library script(s) in
460usr/20sys/798real ms.
Pass 2: analyzed script: 1 probe(s), 2 function(s), 0 embed(s), 0
global(s) in 0usr/0sys/74real ms.
Pass 3: using
cached /home/jimk/.systemtap/cache/3e/stap_3ef244575eb0700481e9d673c7d9d914_354.c
Pass 4: using
cached /home/jimk/.systemtap/cache/3e/stap_3ef244575eb0700481e9d673c7d9d914_354.ko
Pass 5: starting run.
Error inserting module
'/tmp/stapiMOfTu/stap_3ef244575eb0700481e9d673c7d9d914_354.ko': File
exists
Retrying, after attempted removal of module
stap_3ef244575eb0700481e9d673c7d9d914_354 (rc 0)
Hi.
ERROR: The effective user ID of staprun must be set to the root user.
  Check permissions on staprun and ensure it is a setuid root program.
Pass 5: run completed in 10usr/0sys/162real ms.
Pass 5: run failed.  Try again with another '--vp 00001' option.
[jimk@xxx stap]$ which stap
/usr/local/bin/stap
[jimk@xxx stap]$ which staprun
/usr/local/bin/staprun
[jimk@xxx stap]$ ls -l /usr/local/bin/staprun
---s--x--x 1 root root 76026 2009-01-08 10:39 /usr/local/bin/staprun
[jimk@xxx stap]$ lsmod | grep stap
stap_3ef244575eb0700481e9d673c7d9d914_354    27240  0 
stap_7f0af3bd64bc4349367c78489e1f6351_98711   164088  0 
[jimk@xxx stap]$ cat hi.stp
probe begin {
	log("Hi.")
	exit()
}
[jimk@xxx stap]$