We find the current CPU using smp_processor_id() if the event is not bound to a CPU, to find the node for memory allocation. Use the safe numa_node_id() instead, to avoid BUG(). e.g:
BUG: using smp_processor_id() in preemptible [00000000] code: perf/2544 Fixes: 2997aa4063d97fdb39 ("coresight: etb10: implementing AUX API") Cc: Mathieu Poirier <mathieu.poir...@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poul...@arm.com> --- drivers/hwtracing/coresight/coresight-etb10.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c index d5b9ede..3810290 100644 --- a/drivers/hwtracing/coresight/coresight-etb10.c +++ b/drivers/hwtracing/coresight/coresight-etb10.c @@ -374,12 +374,10 @@ static void *etb_alloc_buffer(struct coresight_device *csdev, struct perf_event *event, void **pages, int nr_pages, bool overwrite) { - int node, cpu = event->cpu; + int node; struct cs_buffers *buf; - if (cpu == -1) - cpu = smp_processor_id(); - node = cpu_to_node(cpu); + node = (event->cpu == -1) ? NUMA_NO_NODE : cpu_to_node(event->cpu); buf = kzalloc_node(sizeof(struct cs_buffers), GFP_KERNEL, node); if (!buf) -- 2.7.4