Commit 357b565d authored Mar 21, 2016 by Will Deacon

drivers/perf: arm_pmu: avoid NULL dereference when not using devicetree



Commit c6b90653 ("drivers/perf: arm_pmu: make info messages more
verbose") breaks booting on systems where the PMU is probed without
devicetree (e.g by inspecting the MIDR of the current CPU). In this case,
pdev->dev.of_node is NULL and we shouldn't try to access its ->fullname
field when printing probe error messages.

This patch fixes the probing code to use of_node_full_name, which safely
handles NULL nodes and removes the "Error %i" part of the string, since
it's not terribly useful.

Reported-by: Guenter Roeck <private@roeck-us.net>
Signed-off-by: Will Deacon <will.deacon@arm.com>

parent fe638401

drivers/perf/arm_pmu.c

+3 −4

Original line number	Diff line number	Diff line
		@@ -1002,8 +1002,7 @@ int arm_pmu_device_probe(struct platform_device *pdev,
		}

		if (ret) {
		pr_info("%s: failed to probe PMU! Error %i\n",
		node->full_name, ret);
		pr_info("%s: failed to probe PMU!\n", of_node_full_name(node));
		goto out_free;
		}

		@@ -1023,8 +1022,8 @@ int arm_pmu_device_probe(struct platform_device *pdev,
		out_destroy:
		cpu_pmu_destroy(pmu);
		out_free:
		pr_info("%s: failed to register PMU devices! Error %i\n",
		node->full_name, ret);
		pr_info("%s: failed to register PMU devices!\n",
		of_node_full_name(node));
		kfree(pmu);
		return ret;
		}

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