[PATCH 1/2] perf: arm_dsu: Fix hotplug callback leak in dsu_pmu_init()

[Yuan Can]

dsu_pmu_init() won't remove the callback added by cpuhp_setup_state_multi()
when platform_driver_register() failed. Remove the callback by
cpuhp_remove_multi_state() in fail path.

Similar to the handling of arm_ccn_init() in commit 26242b330093 ("bus:
arm-ccn: Prevent hotplug callback leak")

Fixes: 7520fa99246d ("perf: ARM DynamIQ Shared Unit PMU support")
Signed-off-by: Yuan Can <yuancan at huawei.com>
---
 drivers/perf/arm_dsu_pmu.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/perf/arm_dsu_pmu.c b/drivers/perf/arm_dsu_pmu.c
index 4a15c86f45ef..fe2abb412c00 100644
--- a/drivers/perf/arm_dsu_pmu.c
+++ b/drivers/perf/arm_dsu_pmu.c
@@ -858,7 +858,11 @@ static int __init dsu_pmu_init(void)
 	if (ret < 0)
 		return ret;
 	dsu_pmu_cpuhp_state = ret;
-	return platform_driver_register(&dsu_pmu_driver);
+	ret = platform_driver_register(&dsu_pmu_driver);
+	if (ret)
+		cpuhp_remove_multi_state(dsu_pmu_cpuhp_state);
+
+	return ret;
 }
 
 static void __exit dsu_pmu_exit(void)
-- 
2.17.1