4.6-stable review patch. If anyone has any objections, please let me know.
------------------ From: Julien Grall <[email protected]> commit 0f254c7671e851243412bce6c2e618732831d0f8 upstream. The global variable __oprofile_cpu_pmu is set before the PMU is fully initialized. If an error occurs before the end of the initialization, the PMU will be freed and the variable will contain an invalid pointer. This will result in a kernel crash when perf will be used. Fix it by moving the setting of __oprofile_cpu_pmu when the PMU is fully initialized (i.e when it is no longer possible to fail). Signed-off-by: Julien Grall <[email protected]> Acked-by: Mark Rutland <[email protected]> Signed-off-by: Will Deacon <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/perf/arm_pmu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/perf/arm_pmu.c +++ b/drivers/perf/arm_pmu.c @@ -987,9 +987,6 @@ int arm_pmu_device_probe(struct platform armpmu_init(pmu); - if (!__oprofile_cpu_pmu) - __oprofile_cpu_pmu = pmu; - pmu->plat_device = pdev; if (node && (of_id = of_match_node(of_table, pdev->dev.of_node))) { @@ -1025,6 +1022,9 @@ int arm_pmu_device_probe(struct platform if (ret) goto out_destroy; + if (!__oprofile_cpu_pmu) + __oprofile_cpu_pmu = pmu; + pr_info("enabled with %s PMU driver, %d counters available\n", pmu->name, pmu->num_events);
