From 834fcd298003c10ce450e66960c78893cb1cc4b5 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Thu, 22 Dec 2016 11:02:08 +0100 Subject: [PATCH] perf/x86/intel/cstate: Prevent hotplug callback leak If the pmu registration fails the registered hotplug callbacks are not removed. Wrong in any case, but fatal in case of a modular driver. Replace the nonsensical state names with proper ones while at it. Fixes: 77c34ef1c319 ("perf/x86/intel/cstate: Convert Intel CSTATE to hotplug state machine") Signed-off-by: Thomas Gleixner Cc: Sebastian Siewior Cc: Peter Zijlstra Cc: stable@vger.kernel.org --- arch/x86/events/intel/cstate.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/events/intel/cstate.c b/arch/x86/events/intel/cstate.c index da51e5a3e2ff..fec8a461bdef 100644 --- a/arch/x86/events/intel/cstate.c +++ b/arch/x86/events/intel/cstate.c @@ -594,6 +594,9 @@ static int __init cstate_probe(const struct cstate_model *cm) static inline void cstate_cleanup(void) { + cpuhp_remove_state_nocalls(CPUHP_AP_PERF_X86_CSTATE_ONLINE); + cpuhp_remove_state_nocalls(CPUHP_AP_PERF_X86_CSTATE_STARTING); + if (has_cstate_core) perf_pmu_unregister(&cstate_core_pmu); @@ -606,16 +609,16 @@ static int __init cstate_init(void) int err; cpuhp_setup_state(CPUHP_AP_PERF_X86_CSTATE_STARTING, - "AP_PERF_X86_CSTATE_STARTING", cstate_cpu_init, - NULL); + "perf/x86/cstate:starting", cstate_cpu_init, NULL); cpuhp_setup_state(CPUHP_AP_PERF_X86_CSTATE_ONLINE, - "AP_PERF_X86_CSTATE_ONLINE", NULL, cstate_cpu_exit); + "perf/x86/cstate:online", NULL, cstate_cpu_exit); if (has_cstate_core) { err = perf_pmu_register(&cstate_core_pmu, cstate_core_pmu.name, -1); if (err) { has_cstate_core = false; pr_info("Failed to register cstate core pmu\n"); + cstate_cleanup(); return err; } } @@ -629,8 +632,7 @@ static int __init cstate_init(void) return err; } } - - return err; + return 0; } static int __init cstate_pmu_init(void) @@ -655,8 +657,6 @@ module_init(cstate_pmu_init); static void __exit cstate_pmu_exit(void) { - cpuhp_remove_state_nocalls(CPUHP_AP_PERF_X86_CSTATE_ONLINE); - cpuhp_remove_state_nocalls(CPUHP_AP_PERF_X86_CSTATE_STARTING); cstate_cleanup(); } module_exit(cstate_pmu_exit); -- 2.20.1