diff options
| author | Lianwei Wang <lianwei.wang@gmail.com> | 2016-06-09 23:43:28 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-04-03 06:23:24 +0200 |
| commit | d200cc995188b88832350fae508f79211a284ff7 (patch) | |
| tree | e3afa7c09da7d2c4f93f27efec9bdeda56c980d2 /kernel | |
| parent | 13e84cdbd790a9a567dcb6f206f755e20162ff43 (diff) | |
cpu/hotplug: Handle unbalanced hotplug enable/disable
[ Upstream commit 01b41159066531cc8d664362ff0cd89dd137bbfa ]
When cpu_hotplug_enable() is called unbalanced w/o a preceeding
cpu_hotplug_disable() the code emits a warning, but happily decrements the
disabled counter. This causes the next operations to malfunction.
Prevent the decrement and just emit a warning.
Signed-off-by: Lianwei Wang <lianwei.wang@gmail.com>
Cc: peterz@infradead.org
Cc: linux-pm@vger.kernel.org
Cc: oleg@redhat.com
Link: http://lkml.kernel.org/r/1465541008-12476-1-git-send-email-lianwei.wang@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/cpu.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 40d20bf5de28..42ce0b0ae5c5 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -183,10 +183,17 @@ void cpu_hotplug_disable(void) } EXPORT_SYMBOL_GPL(cpu_hotplug_disable); +static void __cpu_hotplug_enable(void) +{ + if (WARN_ONCE(!cpu_hotplug_disabled, "Unbalanced cpu hotplug enable\n")) + return; + cpu_hotplug_disabled--; +} + 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); @@ -626,7 +633,7 @@ 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; |