Currently it just print a warning message but did not
reset cpu_hotplug_disabled when the enable/disable is
unbalanced. The unbalanced enable/disable will lead
the cpu hotplug work abnormally.
Do nothing if an unablanced hotplug enable detected.
Signed-off-by: Lianwei Wang <lianwei.w...@gmail.com>
---
kernel/cpu.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 3e3f6e49eabb..5e26a3c64934 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -245,6 +245,14 @@ void cpu_hotplug_done(void)
cpuhp_lock_release();
}
+static void __cpu_hotplug_enable(void)
+{
+ if (WARN_ONCE(!cpu_hotplug_disabled, "Unbalanced cpu hotplug enable\n"))
+ return;
+
+ cpu_hotplug_disabled--;
+}
+
/*
* Wait for currently running CPU hotplug operations to complete (if any) and
* disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects
@@ -263,7 +271,7 @@ EXPORT_SYMBOL_GPL(cpu_hotplug_disable);
void cpu_hotplug_enable(void)
{
cpu_maps_update_begin();
- WARN_ON(--cpu_hotplug_disabled < 0);
+ __cpu_hotplug_enable();
cpu_maps_update_done();
}
EXPORT_SYMBOL_GPL(cpu_hotplug_enable);
@@ -1091,7 +1099,7 @@ void enable_nonboot_cpus(void)
/* Allow everyone to use the CPU hotplug again */
cpu_maps_update_begin();
- WARN_ON(--cpu_hotplug_disabled < 0);
+ __cpu_hotplug_enable();
if (cpumask_empty(frozen_cpus))
goto out;
--
1.9.1
