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***

Subject: test patch
Author: heming.zhao@suse.com

#syz test

diff --git a/fs/ocfs2/quota_local.c b/fs/ocfs2/quota_local.c
index de7f12858729..b7555aff169e 100644
--- a/fs/ocfs2/quota_local.c
+++ b/fs/ocfs2/quota_local.c
@@ -1224,7 +1224,10 @@ int ocfs2_create_local_dquot(struct dquot *dquot)
 	int status;
 	u64 pcount;
 
-	down_write(&OCFS2_I(lqinode)->ip_alloc_sem);
+	if (!down_write_trylock(&OCFS2_I(lqinode)->ip_alloc_sem)) {
+		status = -EBUSY;
+		goto out;
+	}
 	chunk = ocfs2_find_free_entry(sb, type, &offset);
 	if (!chunk) {
 		chunk = ocfs2_extend_local_quota_file(sb, type, &offset);