diff options
-rw-r--r-- | kernel/trace/trace_selftest.c | 9 |
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) | |||
57 | 57 | ||
58 | cnt = ring_buffer_entries(tr->buffer); | 58 | cnt = ring_buffer_entries(tr->buffer); |
59 | 59 | ||
60 | /* | ||
61 | * The trace_test_buffer_cpu runs a while loop to consume all data. | ||
62 | * If the calling tracer is broken, and is constantly filling | ||
63 | * the buffer, this will run forever, and hard lock the box. | ||
64 | * We disable the ring buffer while we do this test to prevent | ||
65 | * a hard lock up. | ||
66 | */ | ||
67 | tracing_off(); | ||
60 | for_each_possible_cpu(cpu) { | 68 | for_each_possible_cpu(cpu) { |
61 | ret = trace_test_buffer_cpu(tr, cpu); | 69 | ret = trace_test_buffer_cpu(tr, cpu); |
62 | if (ret) | 70 | if (ret) |
63 | break; | 71 | break; |
64 | } | 72 | } |
73 | tracing_on(); | ||
65 | __raw_spin_unlock(&ftrace_max_lock); | 74 | __raw_spin_unlock(&ftrace_max_lock); |
66 | local_irq_restore(flags); | 75 | local_irq_restore(flags); |
67 | 76 | ||