[PATCH 1/2] coresight: Set affinity to invalid for missing CPU phandle

[Sai Prakash Ranjan]

Affinity defaults to CPU0 in case of missing CPU phandle
and this leads to crashes in some cases because of such
wrong assumption. Fix this by returning -ENODEV in
coresight platform for such cases and then handle it
in the coresight drivers.

Signed-off-by: Sai Prakash Ranjan <saiprakash.ranjan@xxxxxxxxxxxxxx>
---
 drivers/hwtracing/coresight/coresight-platform.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-platform.c b/drivers/hwtracing/coresight/coresight-platform.c
index 3c5ceda8db24..b1ea60c210e1 100644
--- a/drivers/hwtracing/coresight/coresight-platform.c
+++ b/drivers/hwtracing/coresight/coresight-platform.c
@@ -160,15 +160,17 @@ static int of_coresight_get_cpu(struct device *dev)
 
 	if (!dev->of_node)
 		return 0;
+
 	dn = of_parse_phandle(dev->of_node, "cpu", 0);
-	/* Affinity defaults to CPU0 */
+
+	/* Affinity defaults to invalid if no cpu nodes are found*/
 	if (!dn)
-		return 0;
+		return -ENODEV;
+
 	cpu = of_cpu_node_to_id(dn);
 	of_node_put(dn);
 
-	/* Affinity to CPU0 if no cpu nodes are found */
-	return (cpu < 0) ? 0 : cpu;
+	return cpu;
 }
 
 /*
-- 
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