Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block into for-3.18

This is to receive 0a30288da1ae ("blk-mq, percpu_ref: implement a
kludge for SCSI blk-mq stall during probe") which implements
__percpu_ref_kill_expedited() to work around SCSI blk-mq stall.  The
commit reverted and patches to implement proper fix will be added.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/assoc_array.c b/lib/assoc_array.c
index c0b1007011e1..2404d03e251a 100644
--- a/lib/assoc_array.c
+++ b/lib/assoc_array.c
@@ -1723,11 +1723,13 @@ ascend_old_tree:
                 shortcut = assoc_array_ptr_to_shortcut(ptr);
                 slot = shortcut->parent_slot;
                 cursor = shortcut->back_pointer;
+                if (!cursor)
+                        goto gc_complete;
         } else {
                 slot = node->parent_slot;
                 cursor = ptr;
         }
-        BUG_ON(!ptr);
+        BUG_ON(!cursor);
         node = assoc_array_ptr_to_node(cursor);
         slot++;
         goto continue_node;
@@ -1735,7 +1737,7 @@ ascend_old_tree:
 gc_complete:
         edit->set[0].to = new_root;
         assoc_array_apply_edit(edit);
-        edit->array->nr_leaves_on_tree = nr_leaves_on_tree;
+        array->nr_leaves_on_tree = nr_leaves_on_tree;
         return 0;
 
 enomem: