diff options
| author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2017-06-29 10:05:45 -0400 |
|---|---|---|
| committer | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2017-06-29 10:05:45 -0400 |
| commit | 0f17976568b3f72e676450af0c0db6f8752253d6 (patch) | |
| tree | 6bd68d4113163f5205b7ee89a36b162e92b13d20 /kernel/trace/trace_functions.c | |
| parent | 32c1431eea4881a6b17bd7c639315010aeefa452 (diff) | |
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>
Diffstat (limited to 'kernel/trace/trace_functions.c')
| -rw-r--r-- | kernel/trace/trace_functions.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index a3bddbfd0874..a0910c0cdf2e 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -654,6 +654,9 @@ ftrace_trace_onoff_callback(struct trace_array *tr, struct ftrace_hash *hash, { struct ftrace_probe_ops *ops; + if (!tr) + return -ENODEV; + /* we register both traceon and traceoff to this callback */ if (strcmp(cmd, "traceon") == 0) ops = param ? &traceon_count_probe_ops : &traceon_probe_ops; @@ -670,6 +673,9 @@ ftrace_stacktrace_callback(struct trace_array *tr, struct ftrace_hash *hash, { struct ftrace_probe_ops *ops; + if (!tr) + return -ENODEV; + ops = param ? &stacktrace_count_probe_ops : &stacktrace_probe_ops; return ftrace_trace_probe_callback(tr, ops, hash, glob, cmd, @@ -682,6 +688,9 @@ ftrace_dump_callback(struct trace_array *tr, struct ftrace_hash *hash, { struct ftrace_probe_ops *ops; + if (!tr) + return -ENODEV; + ops = &dump_probe_ops; /* Only dump once. */ @@ -695,6 +704,9 @@ ftrace_cpudump_callback(struct trace_array *tr, struct ftrace_hash *hash, { struct ftrace_probe_ops *ops; + if (!tr) + return -ENODEV; + ops = &cpudump_probe_ops; /* Only dump once. */ |