perf/smmuv3: Fix hotplug callback leak in arm_smmu_pmu_init()

[ Upstream commit 6f2d566 ]

arm_smmu_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 26242b3 ("bus:
arm-ccn: Prevent hotplug callback leak")

Fixes: 7d839b4 ("perf/smmuv3: Add arm64 smmuv3 pmu driver")
Signed-off-by: Shang XiaoJing <shangxiaojing@huawei.com>
Reviewed-by: Punit Agrawal <punit.agrawal@bytedance.com>
Link: https://lore.kernel.org/r/20221115115540.6245-3-shangxiaojing@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/perf/arm_smmuv3_pmu.c

@@ -896,14 +896,20 @@ static struct platform_driver smmu_pmu_driver = {
 
 static int __init arm_smmu_pmu_init(void)
 {
+	int ret;
+
 	cpuhp_state_num = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
 						  "perf/arm/pmcg:online",
 						  NULL,
 						  smmu_pmu_offline_cpu);
 	if (cpuhp_state_num < 0)
 		return cpuhp_state_num;
 
-	return platform_driver_register(&smmu_pmu_driver);
+	ret = platform_driver_register(&smmu_pmu_driver);
+	if (ret)
+		cpuhp_remove_multi_state(cpuhp_state_num);
+
+	return ret;
 }
 module_init(arm_smmu_pmu_init);