The counter is unconditionally incremented for each mount allocation. If we set it to 1ULL << 32 we're losing 4294967296 as the first valid non-32 bit mount id. Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> --- fs/namespace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/namespace.c b/fs/namespace.c index 221db9de4729..328087a4df8a 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -70,7 +70,7 @@ static DEFINE_IDA(mnt_id_ida); static DEFINE_IDA(mnt_group_ida); /* Don't allow confusion with old 32bit mount ID */ -#define MNT_UNIQUE_ID_OFFSET (1ULL << 32) +#define MNT_UNIQUE_ID_OFFSET (1ULL << 31) static atomic64_t mnt_id_ctr = ATOMIC64_INIT(MNT_UNIQUE_ID_OFFSET); static struct hlist_head *mount_hashtable __ro_after_init; -- 2.43.0
