padata: Use get_online_cpus/put_online_cpus in padata_free

Add get_online_cpus/put_online_cpus to ensure that no cpu goes
offline during the flushing of the padata percpu queues.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 3 insertions, 0 deletions

diff --git a/kernel/padata.c b/kernel/padata.c
index ca89dfb69805..b1c9857f8402 100644
--- a/kernel/padata.c
+++ b/kernel/padata.c
@@ -763,7 +763,10 @@ void padata_free(struct padata_instance *pinst)
 #ifdef CONFIG_HOTPLUG_CPU
         unregister_hotcpu_notifier(&pinst->cpu_notifier);
 #endif
+        get_online_cpus();
         padata_flush_queues(pinst->pd);
+        put_online_cpus();
+
         padata_free_pd(pinst->pd);
         free_cpumask_var(pinst->cpumask);
         kfree(pinst);