coresight: trbe: Defer the probe on offline CPUs

[platform/kernel/linux-rpi.git] / drivers / hwtracing / coresight / coresight-trbe.c

diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c
index 5f7bb81..7dddb85 100644 (file)
--- a/drivers/hwtracing/coresight/coresight-trbe.c
+++ b/drivers/hwtracing/coresight/coresight-trbe.c
@@ -869,6 +869,10 @@ static void arm_trbe_register_coresight_cpu(struct trbe_drvdata *drvdata, int cp
        if (WARN_ON(trbe_csdev))
                return;
 
+       /* If the TRBE was not probed on the CPU, we shouldn't be here */
+       if (WARN_ON(!cpudata->drvdata))
+               return;
+
        dev = &cpudata->drvdata->pdev->dev;
        desc.name = devm_kasprintf(dev, GFP_KERNEL, "trbe%d", cpu);
        if (!desc.name)
@@ -950,7 +954,9 @@ static int arm_trbe_probe_coresight(struct trbe_drvdata *drvdata)
                return -ENOMEM;
 
        for_each_cpu(cpu, &drvdata->supported_cpus) {
-               smp_call_function_single(cpu, arm_trbe_probe_cpu, drvdata, 1);
+               /* If we fail to probe the CPU, let us defer it to hotplug callbacks */
+               if (smp_call_function_single(cpu, arm_trbe_probe_cpu, drvdata, 1))
+                       continue;
                if (cpumask_test_cpu(cpu, &drvdata->supported_cpus))
                        arm_trbe_register_coresight_cpu(drvdata, cpu);
                if (cpumask_test_cpu(cpu, &drvdata->supported_cpus))