maple_tree: fix handle of invalidated state in mas_wr_store_setup()

If an invalidated maple state is encountered during write, reset the maple
state to MAS_START.  This will result in a re-walk of the tree to the
correct location for the write.

Link: https://lore.kernel.org/all/20230107020126.1627-1-sj@kernel.org/
Link: https://lkml.kernel.org/r/20230120162650.984577-6-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index 5804c59..7c786bd 100644 (file)
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -5609,6 +5609,9 @@ static inline void mte_destroy_walk(struct maple_enode *enode,
 
 static void mas_wr_store_setup(struct ma_wr_state *wr_mas)
 {
+       if (unlikely(mas_is_paused(wr_mas->mas)))
+               mas_reset(wr_mas->mas);
+
        if (!mas_is_start(wr_mas->mas)) {
                if (mas_is_none(wr_mas->mas)) {
                        mas_reset(wr_mas->mas);