[PATCH 2/2] cpufreq: Remove cpu hotplug callbacks only if they were initialized

From: Boris Ostrovsky
Date: Thu Dec 15 2016 - 09:44:59 EST


Since cpu hotplug callbacks are requested for CPUHP_AP_ONLINE_DYN state,
successful callback initialization will result in cpuhp_setup_state()
returning a positive value. Therefore acpi_cpufreq_online being zero
indicates that callbacks have not been installed.

This means that acpi_cpufreq_boost_exit() should only remove them if
acpi_cpufreq_online is positive. Trying to call
cpuhp_remove_state_nocalls(0) will cause a BUG().

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
---
drivers/cpufreq/acpi-cpufreq.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 3a98702..3a2ca0f 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -930,7 +930,7 @@ static void __init acpi_cpufreq_boost_init(void)

static void acpi_cpufreq_boost_exit(void)
{
- if (acpi_cpufreq_online >= 0)
+ if (acpi_cpufreq_online > 0)
cpuhp_remove_state_nocalls(acpi_cpufreq_online);
}

--
1.7.1