[PATCH 2/2] coresight: Abort probe for missing CPU phandle

From: Sai Prakash Ranjan
Date: Thu Jun 20 2019 - 09:51:41 EST


Currently the coresight etm and cpu-debug drivers
assume the affinity to CPU0 returned by coresight
platform and continue the probe in case of missing
CPU phandle. This is not true and leads to crash
in some cases, so abort the probe in case of missing
CPU phandle.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@xxxxxxxxxxxxxx>
---
drivers/hwtracing/coresight/coresight-cpu-debug.c | 3 +++
drivers/hwtracing/coresight/coresight-etm3x.c | 3 +++
drivers/hwtracing/coresight/coresight-etm4x.c | 3 +++
3 files changed, 9 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-cpu-debug.c b/drivers/hwtracing/coresight/coresight-cpu-debug.c
index 07a1367c733f..43f32fa71ff9 100644
--- a/drivers/hwtracing/coresight/coresight-cpu-debug.c
+++ b/drivers/hwtracing/coresight/coresight-cpu-debug.c
@@ -579,6 +579,9 @@ static int debug_probe(struct amba_device *adev, const struct amba_id *id)
return -ENOMEM;

drvdata->cpu = coresight_get_cpu(dev);
+ if (drvdata->cpu == -ENODEV)
+ return -ENODEV;
+
if (per_cpu(debug_drvdata, drvdata->cpu)) {
dev_err(dev, "CPU%d drvdata has already been initialized\n",
drvdata->cpu);
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 225c2982e4fe..882e2751746c 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -816,6 +816,9 @@ static int etm_probe(struct amba_device *adev, const struct amba_id *id)
}

drvdata->cpu = coresight_get_cpu(dev);
+ if (drvdata->cpu == -ENODEV)
+ return -ENODEV;
+
desc.name = devm_kasprintf(dev, GFP_KERNEL, "etm%d", drvdata->cpu);
if (!desc.name)
return -ENOMEM;
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 7fe266194ab5..97d71dbbeb19 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -1101,6 +1101,9 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
spin_lock_init(&drvdata->spinlock);

drvdata->cpu = coresight_get_cpu(dev);
+ if (drvdata->cpu == -ENODEV)
+ return -ENODEV;
+
desc.name = devm_kasprintf(dev, GFP_KERNEL, "etm%d", drvdata->cpu);
if (!desc.name)
return -ENOMEM;
--
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