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

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 26242b330093 ("bus:
arm-ccn: Prevent hotplug callback leak")

Fixes: 7d839b4b9e00 ("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>

diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c
index 00d4c45a8017d7e2632ef51611ac92916bcd1011..25a269d431e455e8fbf88cd8d8e4b7370ce65216 100644 (file)
--- a/drivers/perf/arm_smmuv3_pmu.c
+++ b/drivers/perf/arm_smmuv3_pmu.c
@@ -959,6 +959,8 @@ 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,
@@ -966,7 +968,11 @@ static int __init arm_smmu_pmu_init(void)
        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);