From: Leonard Crestez <leonard.crestez@xxxxxxx> [ Upstream commit 9ee68b314e9aa63ed11b98beb8a68810b8234dcf ] This driver allocates a dynamic cpu hotplug state but never releases it. If reloaded in a loop it will quickly trigger a WARN message: "No more dynamic states available for CPU hotplug" Fix by calling cpuhp_remove_multi_state on remove like several other perf pmu drivers. Also fix the cleanup logic on probe error paths: add the missing cpuhp_remove_multi_state call and properly check the return value from cpuhp_state_add_instant_nocalls. Fixes: 9a66d36cc7ac ("drivers/perf: imx_ddr: Add DDR performance counter support to perf") Acked-by: Joakim Zhang <qiangqing.zhang@xxxxxxx> Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx> Signed-off-by: Will Deacon <will@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/perf/fsl_imx8_ddr_perf.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c index 55083c67b2bb0..95dca2cb52650 100644 --- a/drivers/perf/fsl_imx8_ddr_perf.c +++ b/drivers/perf/fsl_imx8_ddr_perf.c @@ -633,13 +633,17 @@ static int ddr_perf_probe(struct platform_device *pdev) if (ret < 0) { dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n"); - goto ddr_perf_err; + goto cpuhp_state_err; } pmu->cpuhp_state = ret; /* Register the pmu instance for cpu hotplug */ - cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node); + ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node); + if (ret) { + dev_err(&pdev->dev, "Error %d registering hotplug\n", ret); + goto cpuhp_instance_err; + } /* Request irq */ irq = of_irq_get(np, 0); @@ -673,9 +677,10 @@ static int ddr_perf_probe(struct platform_device *pdev) return 0; ddr_perf_err: - if (pmu->cpuhp_state) - cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node); - + cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node); +cpuhp_instance_err: + cpuhp_remove_multi_state(pmu->cpuhp_state); +cpuhp_state_err: ida_simple_remove(&ddr_ida, pmu->id); dev_warn(&pdev->dev, "i.MX8 DDR Perf PMU failed (%d), disabled\n", ret); return ret; @@ -686,6 +691,7 @@ static int ddr_perf_remove(struct platform_device *pdev) struct ddr_pmu *pmu = platform_get_drvdata(pdev); cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node); + cpuhp_remove_multi_state(pmu->cpuhp_state); irq_set_affinity_hint(pmu->irq, NULL); perf_pmu_unregister(&pmu->pmu); -- 2.20.1