run time error - how to debug?

[Peter Teoh]

After an earlier patch for symbols.c in previous email, I run several
stap probes and all encounter the same errors - compilation comples,
insmod ok, and lsmod verified ok, but nothing runs (command was stap
-vvvvvk used for compilation).

Pass 5: starting run.
Running /usr/local/bin/staprun -v -v
/tmp/stapS35EY1/stap_ad3df1525135daf3d6a9f5e4e8dcda2c_14196.ko
staprun:main:237
modpath="/tmp/stapS35EY1/stap_ad3df1525135daf3d6a9f5e4e8dcda2c_14196.ko",
modname="stap_ad3df1525135daf3d6a9f5e4e8dcda2c_14196"
staprun:init_staprun:194 init_staprun
staprun:insert_module:47 inserting module
staprun:insert_module:66 module options: _stp_bufsize=0
Pass 5: run completed in 0usr/0sys/35real ms.
Pass 5: run failed.  Try again with more '-v' (verbose) options.
Keeping temporary directory "/tmp/stapS35EY1"

lsmod|grep stap_ad
stap_ad3df1525135daf3d6a9f5e4e8dcda2c_14196   453132  1

Case 2:

Pass 5: starting run.
Running /usr/local/bin/staprun -v -v
/tmp/stap2mffUi/stap_c0c666510da0e3ba8e16cde92214621f_14763.ko
staprun:main:237
modpath="/tmp/stap2mffUi/stap_c0c666510da0e3ba8e16cde92214621f_14763.ko",
modname="stap_c0c666510da0e3ba8e16cde92214621f_14763"
staprun:init_staprun:194 init_staprun
staprun:insert_module:47 inserting module
staprun:insert_module:66 module options: _stp_bufsize=0
Pass 5: run completed in 0usr/0sys/20real ms.
Pass 5: run failed.  Try again with more '-v' (verbose) options.
Keeping temporary directory "/tmp/stap2mffUi"

lsmod |grep stap_c0c
stap_c0c666510da0e3ba8e16cde92214621f_14763   448436  1

How do I debug this?
-- 
Regards,
Peter Teoh