1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/infiniband/hw/qib/qib_debugfs.c b/drivers/infiniband/hw/qib/qib_debugfs.c
index 5e75b43c596b..5bad8e3b40bb 100644
--- a/drivers/infiniband/hw/qib/qib_debugfs.c
+++ b/drivers/infiniband/hw/qib/qib_debugfs.c
@@ -189,27 +189,32 @@ static int _ctx_stats_seq_show(struct seq_file *s, void *v)
 DEBUGFS_FILE(ctx_stats)
 
 static void *_qp_stats_seq_start(struct seq_file *s, loff_t *pos)
+        __acquires(RCU)
 {
         struct qib_qp_iter *iter;
         loff_t n = *pos;
 
-        rcu_read_lock();
         iter = qib_qp_iter_init(s->private);
+
+        /* stop calls rcu_read_unlock */
+        rcu_read_lock();
+
         if (!iter)
                 return NULL;
 
-        while (n--) {
+        do {
                 if (qib_qp_iter_next(iter)) {
                         kfree(iter);
                         return NULL;
                 }
-        }
+        } while (n--);
 
         return iter;
 }
 
 static void *_qp_stats_seq_next(struct seq_file *s, void *iter_ptr,
                                    loff_t *pos)
+        __must_hold(RCU)
 {
         struct qib_qp_iter *iter = iter_ptr;
 
@@ -224,6 +229,7 @@ static void *_qp_stats_seq_next(struct seq_file *s, void *iter_ptr,
 }
 
 static void _qp_stats_seq_stop(struct seq_file *s, void *iter_ptr)
+        __releases(RCU)
 {
         rcu_read_unlock();
 }