1 files changed, 15 insertions, 7 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 3c7b537bf908..ae21919f15e1 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -988,9 +988,10 @@ static void cfq_group_served(struct cfq_data *cfqd, struct cfq_group *cfqg,
 
         cfq_log_cfqg(cfqd, cfqg, "served: vt=%llu min_vt=%llu", cfqg->vdisktime,
                                         st->min_vdisktime);
-        cfq_log_cfqq(cfqq->cfqd, cfqq, "sl_used=%u disp=%u charge=%u iops=%u"
-                        " sect=%u", used_sl, cfqq->slice_dispatch, charge,
-                        iops_mode(cfqd), cfqq->nr_sectors);
+        cfq_log_cfqq(cfqq->cfqd, cfqq,
+                     "sl_used=%u disp=%u charge=%u iops=%u sect=%lu",
+                     used_sl, cfqq->slice_dispatch, charge,
+                     iops_mode(cfqd), cfqq->nr_sectors);
         cfq_blkiocg_update_timeslice_used(&cfqg->blkg, used_sl,
                                           unaccounted_sl);
         cfq_blkiocg_set_start_empty_time(&cfqg->blkg);
@@ -2023,8 +2024,8 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd)
          */
         if (sample_valid(cic->ttime_samples) &&
             (cfqq->slice_end - jiffies < cic->ttime_mean)) {
-                cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%d",
-                                cic->ttime_mean);
+                cfq_log_cfqq(cfqd, cfqq, "Not idling. think_time:%lu",
+                             cic->ttime_mean);
                 return;
         }
 
@@ -2772,8 +2773,14 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
         smp_wmb();
         cic->key = cfqd_dead_key(cfqd);
 
-        if (ioc->ioc_data == cic)
+        rcu_read_lock();
+        if (rcu_dereference(ioc->ioc_data) == cic) {
+                rcu_read_unlock();
+                spin_lock(&ioc->lock);
                 rcu_assign_pointer(ioc->ioc_data, NULL);
+                spin_unlock(&ioc->lock);
+        } else
+                rcu_read_unlock();
 
         if (cic->cfqq[BLK_RW_ASYNC]) {
                 cfq_exit_cfqq(cfqd, cic->cfqq[BLK_RW_ASYNC]);
@@ -3080,7 +3087,8 @@ cfq_drop_dead_cic(struct cfq_data *cfqd, struct io_context *ioc,
 
         spin_lock_irqsave(&ioc->lock, flags);
 
-        BUG_ON(ioc->ioc_data == cic);
+        BUG_ON(rcu_dereference_check(ioc->ioc_data,
+                lockdep_is_held(&ioc->lock)) == cic);
 
         radix_tree_delete(&ioc->radix_root, cfqd->cic_index);
         hlist_del_rcu(&cic->cic_list);