dm: use READ_ONCE in dm_blk_report_zones

The functon dm_blk_report_zones reads md->zone_revalidate_map, however it
may change while the function is running. Use READ_ONCE.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Fixes: 37f53a2c60d0 ("dm: fix dm_blk_report_zones")
Reviewed-by: Benjamin Marzinski <bmarzins@redhat.com>

diff --git a/drivers/md/dm-zone.c b/drivers/md/dm-zone.c
index bc4e45862a220457a8d7012c87f3516bfe66f77d..f29acf64429a757d6ff8edf78ee6626430da6e94 100644 (file)
--- a/drivers/md/dm-zone.c
+++ b/drivers/md/dm-zone.c
@@ -50,7 +50,7 @@ int dm_blk_report_zones(struct gendisk *disk, sector_t sector,
 {
        struct mapped_device *md = disk->private_data;
        struct dm_table *map;
-       struct dm_table *zone_revalidate_map = md->zone_revalidate_map;
+       struct dm_table *zone_revalidate_map = READ_ONCE(md->zone_revalidate_map);
        int srcu_idx, ret = -EIO;
        bool put_table = false;