coresight: etm: perf: Fix warning caused by etm_setup_aux failure

When coresight_build_path() fails on all the cpus, etm_setup_aux
calls etm_free_aux() to free allocated event_data.
WARN_ON(cpumask_empty(mask) will be triggered since cpu mask is empty.
Check event_data->snk_config is not NULL first to avoid this
warning.

Fixes: f5200aa9831f38 ("coresight: perf: Refactor function free_event_data()")
Reviewed-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200928163513.70169-9-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 644805e0a9ecf99c4e6f8ce76ee3826ab4695774..47894a0dcf5e0e58a5cf0a226d3668a2bcf441b5 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -126,10 +126,10 @@ static void free_sink_buffer(struct etm_event_data *event_data)
        cpumask_t *mask = &event_data->mask;
        struct coresight_device *sink;
 
-       if (WARN_ON(cpumask_empty(mask)))
+       if (!event_data->snk_config)
                return;
 
-       if (!event_data->snk_config)
+       if (WARN_ON(cpumask_empty(mask)))
                return;
 
        cpu = cpumask_first(mask);