Merge branch 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git...

[pandora-kernel.git] / block / cfq-iosched.c

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index f379943..ae21919 100644 (file)
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -2773,11 +2773,14 @@ static void __cfq_exit_single_io_context(struct cfq_data *cfqd,
        smp_wmb();
        cic->key = cfqd_dead_key(cfqd);
 
+       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]);
@@ -3084,7 +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);