LTTng » LTTng-UST

Version used:
userspace-rcu: origin/master, commit ae51baf
lttng-ust : origin/master, commit 9e4d42a
lttng-tools : origin/master, commit 5168918

When the following filter is enabled: --filter "stringfield=='text'"
for tracepoint: ust_tests_demo2:loop from program "demo" which is
supplied with lttng-ust/test/, the demo program gets segmentation
fault when the session is started.

Steps to reproduce:

1)_ lttng create TC4 -o /cluster/temp/sessiondir/TC4_c
2)_ lttng enable-event ust_tests_demo2:loop -u --filter "stringfield=='text'"
3)_ LTTNG_UST_DEBUG=1 ./demo-trace 50 &
4)_ lttng start
5)_ ./demo-trace: line 3: 14504 Segmentation fault LD_PRELOAD=./liblttng-ust-provider-ust-tests-demo.so:./liblttng-ust-provider-ust-tests-demo3.so ./demo ${*}

The above has been also observed when using our own instrumented application.
(ie: when a filter on a string is given, segmentation fault will occur for the instr app)

Please, see log enclosed.