diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index e8347461c8dd..69ab10c9237f 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -417,9 +417,10 @@ static void __btrfs_dump_space_info(struct btrfs_fs_info *fs_info,
 {
 	lockdep_assert_held(&info->lock);
 
-	btrfs_info(fs_info, "space_info %llu has %llu free, is %sfull",
+	/* The free space could be negative in case of overcommit */
+	btrfs_info(fs_info, "space_info %llu has %lld free, is %sfull",
 		   info->flags,
-		   info->total_bytes - btrfs_space_info_used(info, true),
+		   (s64)(info->total_bytes - btrfs_space_info_used(info, true)),
 		   info->full ? "" : "not ");
 	btrfs_info(fs_info,
 		"space_info total=%llu, used=%llu, pinned=%llu, reserved=%llu, may_use=%llu, readonly=%llu",