2 files changed, 12 insertions, 2 deletions

diff --git a/include/linux/crush/crush.h b/include/linux/crush/crush.h
index 92e165d417a6..07eed95e10c7 100644
--- a/include/linux/crush/crush.h
+++ b/include/linux/crush/crush.h
@@ -193,7 +193,7 @@ struct crush_choose_arg {
 struct crush_choose_arg_map {
 #ifdef __KERNEL__
         struct rb_node node;
-        u64 choose_args_index;
+        s64 choose_args_index;
 #endif
         struct crush_choose_arg *args; /*!< replacement for each bucket
                                             in the crushmap */
diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c
index 64ae9f89773a..eb57a06373ca 100644
--- a/net/ceph/osdmap.c
+++ b/net/ceph/osdmap.c
@@ -2301,10 +2301,17 @@ static u32 raw_pg_to_pps(struct ceph_pg_pool_info *pi,
         }
 }
 
+/*
+ * Magic value used for a "default" fallback choose_args, used if the
+ * crush_choose_arg_map passed to do_crush() does not exist.  If this
+ * also doesn't exist, fall back to canonical weights.
+ */
+#define CEPH_DEFAULT_CHOOSE_ARGS        -1
+
 static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
                     int *result, int result_max,
                     const __u32 *weight, int weight_max,
-                    u64 choose_args_index)
+                    s64 choose_args_index)
 {
         struct crush_choose_arg_map *arg_map;
         int r;
@@ -2313,6 +2320,9 @@ static int do_crush(struct ceph_osdmap *map, int ruleno, int x,
 
         arg_map = lookup_choose_arg_map(&map->crush->choose_args,
                                         choose_args_index);
+        if (!arg_map)
+                arg_map = lookup_choose_arg_map(&map->crush->choose_args,
+                                                CEPH_DEFAULT_CHOOSE_ARGS);
 
         mutex_lock(&map->crush_workspace_mutex);
         r = crush_do_rule(map->crush, ruleno, x, result, result_max,