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drivers: perf: Fix wrong put_cpu() placement

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Unfortunately, the wrong patch version was merged which places the
put_cpu() after enabling a static key, which is not safe as pointed by
Will [1], so move put_cpu() before to avoid this.

Fixes: 2840dadf0d ("drivers: perf: Fix smp_processor_id() use in preemptible code")
Reported-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/all/20240827125335.GD4772@willie-the-truck/ [1]
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20241112113422.617954-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Alexandre Ghiti 2024-11-12 12:34:22 +01:00 committed by Palmer Dabbelt
parent 59b723cd2a
commit 57f7c7dc78
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GPG Key ID: 2E1319F35FBB1889
1 changed files with 2 additions and 2 deletions
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4
drivers/perf/riscv_pmu_sbi.c
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@ -1393,8 +1393,9 @@ static int pmu_sbi_device_probe(struct platform_device *pdev)
goto out_unregister;
cpu = get_cpu();
ret = pmu_sbi_snapshot_setup(pmu, cpu);
put_cpu();
if (ret) {
/* Snapshot is an optional feature. Continue if not available */
pmu_sbi_snapshot_free(pmu);
@ -1408,7 +1409,6 @@ static int pmu_sbi_device_probe(struct platform_device *pdev)
*/
static_branch_enable(&sbi_pmu_snapshot_available);
}
put_cpu();
}
register_sysctl("kernel", sbi_pmu_sysctl_table);