Skip to content

Commit

Permalink
drivers/perf: hisi: use cpuhp_state_remove_instance_nocalls() for his…
Browse files Browse the repository at this point in the history
…i_hns3_pmu uninit process

When tearing down a 'hisi_hns3' PMU, we mistakenly run the CPU hotplug
callbacks after the device has been unregistered, leading to fireworks
when we try to execute empty function callbacks within the driver:

  | Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
  | CPU: 0 PID: 15 Comm: cpuhp/0 Tainted: G        W  O      5.12.0-rc4+ #1
  | Hardware name:  , BIOS KpxxxFPGA 1P B600 V143 04/22/2021
  | pstate: 80400009 (Nzcv daif +PAN -UAO -TCO BTYPE=--)
  | pc : perf_pmu_migrate_context+0x98/0x38c
  | lr : perf_pmu_migrate_context+0x94/0x38c
  |
  | Call trace:
  |  perf_pmu_migrate_context+0x98/0x38c
  |  hisi_hns3_pmu_offline_cpu+0x104/0x12c [hisi_hns3_pmu]

Use cpuhp_state_remove_instance_nocalls() instead of
cpuhp_state_remove_instance() so that the notifiers don't execute after
the PMU device has been unregistered.

Fixes: 66637ab ("drivers/perf: hisi: add driver for HNS3 PMU")
Signed-off-by: Hao Chen <chenhao418@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
Reviewed-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20231019091352.998964-1-shaojijie@huawei.com
[will: Rewrote commit message]
Signed-off-by: Will Deacon <will@kernel.org>
  • Loading branch information
Hao Chen authored and willdeacon committed Oct 19, 2023
1 parent 1f33cde commit 50b5607
Showing 1 changed file with 4 additions and 4 deletions.
8 changes: 4 additions & 4 deletions drivers/perf/hisilicon/hns3_pmu.c
Original file line number Diff line number Diff line change
Expand Up @@ -1556,8 +1556,8 @@ static int hns3_pmu_init_pmu(struct pci_dev *pdev, struct hns3_pmu *hns3_pmu)
ret = perf_pmu_register(&hns3_pmu->pmu, hns3_pmu->pmu.name, -1);
if (ret) {
pci_err(pdev, "failed to register perf PMU, ret = %d.\n", ret);
cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_HNS3_PMU_ONLINE,
&hns3_pmu->node);
cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_HNS3_PMU_ONLINE,
&hns3_pmu->node);
}

return ret;
Expand All @@ -1568,8 +1568,8 @@ static void hns3_pmu_uninit_pmu(struct pci_dev *pdev)
struct hns3_pmu *hns3_pmu = pci_get_drvdata(pdev);

perf_pmu_unregister(&hns3_pmu->pmu);
cpuhp_state_remove_instance(CPUHP_AP_PERF_ARM_HNS3_PMU_ONLINE,
&hns3_pmu->node);
cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_HNS3_PMU_ONLINE,
&hns3_pmu->node);
}

static int hns3_pmu_init_dev(struct pci_dev *pdev)
Expand Down

0 comments on commit 50b5607

Please sign in to comment.