diff options
Diffstat (limited to 'kernel/locking/lockdep.c')
| -rw-r--r-- | kernel/locking/lockdep.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 2270ec68f10a..dc03fe856729 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -5402,11 +5402,14 @@ static struct pin_cookie __lock_pin_lock(struct lockdep_map *lock) if (match_held_lock(hlock, lock)) { /* - * Grab 16bits of randomness; this is sufficient to not - * be guessable and still allows some pin nesting in - * our u32 pin_count. + * Grab 6bits of randomness; this is barely sufficient + * to not be guessable and still allows some 32 levels + * of pin nesting in our u12 pin_count. */ - cookie.val = 1 + (prandom_u32() >> 16); + cookie.val = 1 + (prandom_u32() >> 26); + if (DEBUG_LOCKS_WARN_ON(hlock->pin_count + cookie.val >= 1 << 12)) + return NIL_COOKIE; + hlock->pin_count += cookie.val; return cookie; } |