From 966c08de7c2c9bcac13e2cb9e769a39582d5389f Mon Sep 17 00:00:00 2001 From: Oliver O'Halloran Date: Thu, 6 Feb 2020 17:26:22 +1100 Subject: cpufreq: powernv: Fix unsafe notifiers The PowerNV cpufreq driver registers two notifiers: one to catch throttle messages from the OCC and one to bump the CPU frequency back to normal before a reboot. Both require the cpufreq driver to be registered in order to function since the notifier callbacks use various cpufreq_*() functions. Right now we register both notifiers before we've initialised the driver. This seems to work, but we should head off any protential problems by registering the notifiers after the driver is initialised. Signed-off-by: Oliver O'Halloran Reviewed-by: Gautham R. Shenoy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200206062622.28235-2-oohall@gmail.com --- drivers/cpufreq/powernv-cpufreq.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 1806b1da4366..03798c4326c6 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -1114,9 +1114,6 @@ static int __init powernv_cpufreq_init(void) if (rc) goto out; - register_reboot_notifier(&powernv_cpufreq_reboot_nb); - opal_message_notifier_register(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb); - if (powernv_pstate_info.wof_enabled) powernv_cpufreq_driver.boost_enabled = true; else @@ -1125,15 +1122,17 @@ static int __init powernv_cpufreq_init(void) rc = cpufreq_register_driver(&powernv_cpufreq_driver); if (rc) { pr_info("Failed to register the cpufreq driver (%d)\n", rc); - goto cleanup_notifiers; + goto cleanup; } if (powernv_pstate_info.wof_enabled) cpufreq_enable_boost_support(); + register_reboot_notifier(&powernv_cpufreq_reboot_nb); + opal_message_notifier_register(OPAL_MSG_OCC, &powernv_cpufreq_opal_nb); + return 0; -cleanup_notifiers: - unregister_all_notifiers(); +cleanup: clean_chip_info(); out: pr_info("Platform driver disabled. System does not support PState control\n"); -- cgit v1.2.3