drivers/perf: hisi: add NULL check for name

When allocations fails that can be NULL now.

If the name provided is NULL, then the initialization process of the PMU
type and dev will be skipped in function perf_pmu_register().
Consequently, the PMU will not be able to register into the kernel.
Moreover, in the case of unregister the PMU, the function device_del()
will need to handle NULL pointers, which potentially can cause issues.

So move this allocation above the cpuhp_state_add_instance() and directly
return if it does fail.

Signed-off-by: Junhao He <hejunhao3@huawei.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20230403081423.62460-3-hejunhao3@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c
index 8a3d74ddcd6dd92ef848f52baa25bcb842220ab1..ffb039d05d07b2a03e07c5a99c0bc8a0c7e9c0a8 100644 (file)
--- a/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_ddrc_pmu.c
@@ -499,13 +499,6 @@ static int hisi_ddrc_pmu_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
-       ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE,
-                                      &ddrc_pmu->node);
-       if (ret) {
-               dev_err(&pdev->dev, "Error %d registering hotplug;\n", ret);
-               return ret;
-       }
-
        if (ddrc_pmu->identifier >= HISI_PMU_V2)
                name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
                                      "hisi_sccl%u_ddrc%u_%u",
@@ -516,6 +509,16 @@ static int hisi_ddrc_pmu_probe(struct platform_device *pdev)
                                      "hisi_sccl%u_ddrc%u", ddrc_pmu->sccl_id,
                                      ddrc_pmu->index_id);
 
+       if (!name)
+               return -ENOMEM;
+
+       ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_HISI_DDRC_ONLINE,
+                                      &ddrc_pmu->node);
+       if (ret) {
+               dev_err(&pdev->dev, "Error %d registering hotplug;\n", ret);
+               return ret;
+       }
+
        hisi_pmu_init(ddrc_pmu, THIS_MODULE);
 
        ret = perf_pmu_register(&ddrc_pmu->pmu, name, -1);

diff --git a/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c b/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c
index 5701a84edb0ee5c99f078bad4527225a0eb89004..15caf99e1eefe22f2cd6399258eeb73702bee790 100644 (file)
--- a/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_hha_pmu.c
@@ -510,6 +510,11 @@ static int hisi_hha_pmu_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
+       name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "hisi_sccl%u_hha%u",
+                             hha_pmu->sccl_id, hha_pmu->index_id);
+       if (!name)
+               return -ENOMEM;
+
        ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_HISI_HHA_ONLINE,
                                       &hha_pmu->node);
        if (ret) {
@@ -517,8 +522,6 @@ static int hisi_hha_pmu_probe(struct platform_device *pdev)
                return ret;
        }
 
-       name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "hisi_sccl%u_hha%u",
-                             hha_pmu->sccl_id, hha_pmu->index_id);
        hisi_pmu_init(hha_pmu, THIS_MODULE);
 
        ret = perf_pmu_register(&hha_pmu->pmu, name, -1);

diff --git a/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c b/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c
index 68596b56634439b03dfc49a1985d4d87f3bed344..794dbcd19b7a7146b97c0f7f1b55e6b0e5f92ffd 100644 (file)
--- a/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c
+++ b/drivers/perf/hisilicon/hisi_uncore_l3c_pmu.c
@@ -544,6 +544,11 @@ static int hisi_l3c_pmu_probe(struct platform_device *pdev)
        if (ret)
                return ret;
 
+       name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "hisi_sccl%u_l3c%u",
+                             l3c_pmu->sccl_id, l3c_pmu->ccl_id);
+       if (!name)
+               return -ENOMEM;
+
        ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_HISI_L3_ONLINE,
                                       &l3c_pmu->node);
        if (ret) {
@@ -551,12 +556,6 @@ static int hisi_l3c_pmu_probe(struct platform_device *pdev)
                return ret;
        }
 
-       /*
-        * CCL_ID is used to identify the L3C in the same SCCL which was
-        * used _UID by mistake.
-        */
-       name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "hisi_sccl%u_l3c%u",
-                             l3c_pmu->sccl_id, l3c_pmu->ccl_id);
        hisi_pmu_init(l3c_pmu, THIS_MODULE);
 
        ret = perf_pmu_register(&l3c_pmu->pmu, name, -1);