ocfs2: fix BUG in ocfs2_downconvert_thread_do_work()

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / ocfs2 / dlmglue.c

diff --git a/fs/ocfs2/dlmglue.c b/fs/ocfs2/dlmglue.c
index 3a44a648dae7709b1cd5431c426cf3b9e057e54a..b294deb27d173fde086a6e55fe68448a5c93547e 100644 (file)
--- a/fs/ocfs2/dlmglue.c
+++ b/fs/ocfs2/dlmglue.c
@@ -3971,9 +3971,13 @@ static void ocfs2_downconvert_thread_do_work(struct ocfs2_super *osb)
        osb->dc_work_sequence = osb->dc_wake_sequence;
 
        processed = osb->blocked_lock_count;
-       while (processed) {
-               BUG_ON(list_empty(&osb->blocked_lock_list));
-
+       /*
+        * blocked lock processing in this loop might call iput which can
+        * remove items off osb->blocked_lock_list. Downconvert up to
+        * 'processed' number of locks, but stop short if we had some
+        * removed in ocfs2_mark_lockres_freeing when downconverting.
+        */
+       while (processed && !list_empty(&osb->blocked_lock_list)) {
                lockres = list_entry(osb->blocked_lock_list.next,
                                     struct ocfs2_lock_res, l_blocked_list);
                list_del_init(&lockres->l_blocked_list);