1 files changed, 16 insertions, 7 deletions

diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c
index 14c6fae6fe6b..b09763fe5da1 100644
--- a/arch/s390/mm/pgtable.c
+++ b/arch/s390/mm/pgtable.c
@@ -71,12 +71,15 @@ static void rcu_table_freelist_callback(struct rcu_head *head)
 
 void rcu_table_freelist_finish(void)
 {
-        struct rcu_table_freelist *batch = __get_cpu_var(rcu_table_freelist);
+        struct rcu_table_freelist **batchp = &get_cpu_var(rcu_table_freelist);
+        struct rcu_table_freelist *batch = *batchp;
 
         if (!batch)
-                return;
+                goto out;
         call_rcu(&batch->rcu, rcu_table_freelist_callback);
-        __get_cpu_var(rcu_table_freelist) = NULL;
+        *batchp = NULL;
+out:
+        put_cpu_var(rcu_table_freelist);
 }
 
 static void smp_sync(void *arg)
@@ -141,20 +144,23 @@ void crst_table_free_rcu(struct mm_struct *mm, unsigned long *table)
 {
         struct rcu_table_freelist *batch;
 
+        preempt_disable();
         if (atomic_read(&mm->mm_users) < 2 &&
             cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
                 crst_table_free(mm, table);
-                return;
+                goto out;
         }
         batch = rcu_table_freelist_get(mm);
         if (!batch) {
                 smp_call_function(smp_sync, NULL, 1);
                 crst_table_free(mm, table);
-                return;
+                goto out;
         }
         batch->table[--batch->crst_index] = table;
         if (batch->pgt_index >= batch->crst_index)
                 rcu_table_freelist_finish();
+out:
+        preempt_enable();
 }
 
 #ifdef CONFIG_64BIT
@@ -323,16 +329,17 @@ void page_table_free_rcu(struct mm_struct *mm, unsigned long *table)
         struct page *page;
         unsigned long bits;
 
+        preempt_disable();
         if (atomic_read(&mm->mm_users) < 2 &&
             cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) {
                 page_table_free(mm, table);
-                return;
+                goto out;
         }
         batch = rcu_table_freelist_get(mm);
         if (!batch) {
                 smp_call_function(smp_sync, NULL, 1);
                 page_table_free(mm, table);
-                return;
+                goto out;
         }
         bits = (mm->context.has_pgste) ? 3UL : 1UL;
         bits <<= (__pa(table) & (PAGE_SIZE - 1)) / 256 / sizeof(unsigned long);
@@ -345,6 +352,8 @@ void page_table_free_rcu(struct mm_struct *mm, unsigned long *table)
         batch->table[batch->pgt_index++] = table;
         if (batch->pgt_index >= batch->crst_index)
                 rcu_table_freelist_finish();
+out:
+        preempt_enable();
 }
 
 /*