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-rw-r--r--kernel/trace/trace_selftest.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 88c8eb70f54a..a7e0ef662f9f 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -57,11 +57,20 @@ static int trace_test_buffer(struct trace_array *tr, unsigned long *count)
cnt = ring_buffer_entries(tr->buffer);
+ /*
+ * The trace_test_buffer_cpu runs a while loop to consume all data.
+ * If the calling tracer is broken, and is constantly filling
+ * the buffer, this will run forever, and hard lock the box.
+ * We disable the ring buffer while we do this test to prevent
+ * a hard lock up.
+ */
+ tracing_off();
for_each_possible_cpu(cpu) {
ret = trace_test_buffer_cpu(tr, cpu);
if (ret)
break;
}
+ tracing_on();
__raw_spin_unlock(&ftrace_max_lock);
local_irq_restore(flags);