Systemtap incompatible with ubuntu-18.04?

Systemtap incompatible with ubuntu-18.04?

[Bill Broadley]

Greetings,

I've been using systemtap to track NFSd activity on several ubuntu-16.04
machines with no problems.

Running:
stap nfsd-trace.stp

I have a puppet module that installs systemtap and the kernel-debug info required.

I tried the same on ubuntu-18.04 (using the ubuntu provided systemtap):
 # /usr/bin/stap ./testsuite/systemtap.examples/network/nfsd-trace.stp
 semantic error: while processing probe
 module("nfsd").function("nfsd4_lookup@/build/linux-lZKWha/linux-4.15.0/fs/nfsd
 /nfs4proc.c:735").call from: nfsd.proc4.lookup from: nfsd.proc.lookup from:
 nfsd.proc.entries from: nfsd.proc.entries

So I installed the current systemtap from git and:

root@foo:/share/apps/systemtap-2018-09-27# ./bin/stap
./share/systemtap/examples/network/nfsd-trace.stp
semantic error: while processing probe
module("nfsd").function("nfsd4_read@/build/linux-lZKWha/linux-4.15.0/fs/nfsd/nfs4proc.c:744").call
from: nfsd.proc4.read from: nfsd.proc.read from: nfsd.proc.entries from:
nfsd.proc.entries

semantic error: failed to retrieve location attribute for 'read' [man
error::dwarf]: identifier '$read' at
/share/apps/systemtap-2018-09-27/share/systemtap/tapset/linux/nfsd.stp:570:10
        dieoffset: 0x1b87de from
/usr/lib/debug/lib/modules/4.15.0-22-generic/kernel/fs/nfsd/nfsd.ko
        function: nfsd4_read at
/build/linux-lZKWha/linux-4.15.0/fs/nfsd/nfs4proc.c:746
        source: 	count = $read->rd_length
                	        ^
The kernel used is:
4.15.0-22-generic

I installed linux-image-4.15.0-22-generic-dbgsym:
2018-09-20 18:38:50 status installed linux-image-4.15.0-22-generic-dbgsym:amd64
4.15.0-22.24

Any ideas on how to get it working?

Re: Systemtap incompatible with ubuntu-18.04?

[Bill Broadley]

Thanks to:

https://sourceware.org/git/gitweb.cgi?p=systemtap.git;a=commitdiff;h=8bc64034509474bee3fb7996b2a9e74c8bc27281

And related changes I'm happy to report that using systemtap from the current
git now works with ubuntu-18.04.  In particular the nfsd-trace.stp example.

Thanks for everyone's help.