From: Masami Hiramatsu (Google) <[email protected]>
mmio_reset_data() is called during tracer initialization, reset, and
start. While it resets overrun_detected and prev_overruns, it neglects
to reset dropped_count. Consequently, dropped event counts from prior
tracing sessions persist in dropped_count and corrupt overrun reports
in subsequent runs.
Fix this by explicitly calling atomic_set(&dropped_count, 0) in
mmio_reset_data().
Fixes: 173ed24ee2d6 ("mmiotrace: count events lost due to not recording")
Assisted-by: Antigravity:gemini-3.6-flash
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>
---
kernel/trace/trace_mmiotrace.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c
index b88b8d9923ad..e064ba3f28cb 100644
--- a/kernel/trace/trace_mmiotrace.c
+++ b/kernel/trace/trace_mmiotrace.c
@@ -29,6 +29,7 @@ static void mmio_reset_data(struct trace_array *tr)
{
overrun_detected = false;
prev_overruns = 0;
+ atomic_set(&dropped_count, 0);
tracing_reset_online_cpus(&tr->array_buffer);
}