ftrace: Fix regression with module command in stack_trace_filter
When doing the following command:
# echo ":mod:kvm_intel" > /sys/kernel/tracing/stack_trace_filter
it triggered a crash.
This happened with the clean up of probes. It required all callers to the
regex function (doing ftrace filtering) to have ops->private be a pointer to
a trace_array. But for the stack tracer, that is not the case.
Allow for the ops->private to be NULL, and change the function command
callbacks to handle the trace_array pointer being NULL as well.
Fixes: d2afd57a4b96 ("tracing/ftrace: Allow instances to have their own function probes")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
4 files changed