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| author | Lianwei Wang <lianwei.wang@gmail.com> | 2016-06-09 23:43:28 -0700 |
|---|---|---|
| committer | Lianwei Wang <lianwei.wang@gmail.com> | 2016-10-22 23:54:57 -0700 |
| commit | a3c8dc25c446485dcbf8a978f755eead9eac3671 (patch) | |
| tree | 8864f8cc65f6a12f7677f922475b7d468399c5d9 | |
| parent | 4a8b645cef3caa87b85269078d9e1f02115107b6 (diff) | |
UPSTREAM: cpu/hotplug: Handle unbalanced hotplug enable/disable
(cherry picked from 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>
| -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 9ced7c751648..c8a1751be224 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -185,10 +185,17 @@ 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); @@ -631,7 +638,7 @@ 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; |