Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "A few fixes for lockdep:

   - initialize lockdep internal RCU head after initializing RCU

   - prevent use after free in a alloc_workqueue() error handling path

   - plug a memory leak in the workqueue core which fails to free a
     dynamically allocated lock name.

   - make Clang happy"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  workqueue, lockdep: Fix a memory leak in wq->lock_name
  workqueue, lockdep: Fix an alloc_workqueue() error path
  locking/lockdep: Only call init_rcu_head() after RCU has been initialized
  locking/lockdep: Avoid a Clang warning
This commit is contained in:
Linus Torvalds 2019-03-10 13:48:14 -07:00
commit 9e55f87c0e
2 changed files with 18 additions and 5 deletions

View File

@ -842,7 +842,9 @@ static bool class_lock_list_valid(struct lock_class *c, struct list_head *h)
return true;
}
static u16 chain_hlocks[];
#ifdef CONFIG_PROVE_LOCKING
static u16 chain_hlocks[MAX_LOCKDEP_CHAIN_HLOCKS];
#endif
static bool check_lock_chain_key(struct lock_chain *chain)
{
@ -980,15 +982,22 @@ static inline void check_data_structures(void) { }
*/
static void init_data_structures_once(void)
{
static bool initialization_happened;
static bool ds_initialized, rcu_head_initialized;
int i;
if (likely(initialization_happened))
if (likely(rcu_head_initialized))
return;
initialization_happened = true;
if (system_state >= SYSTEM_SCHEDULING) {
init_rcu_head(&delayed_free.rcu_head);
rcu_head_initialized = true;
}
if (ds_initialized)
return;
ds_initialized = true;
init_rcu_head(&delayed_free.rcu_head);
INIT_LIST_HEAD(&delayed_free.pf[0].zapped);
INIT_LIST_HEAD(&delayed_free.pf[1].zapped);

View File

@ -3445,6 +3445,8 @@ static void wq_init_lockdep(struct workqueue_struct *wq)
lock_name = kasprintf(GFP_KERNEL, "%s%s", "(wq_completion)", wq->name);
if (!lock_name)
lock_name = wq->name;
wq->lock_name = lock_name;
lockdep_init_map(&wq->lockdep_map, lock_name, &wq->key, 0);
}
@ -4291,6 +4293,8 @@ struct workqueue_struct *alloc_workqueue(const char *fmt,
return wq;
err_free_wq:
wq_unregister_lockdep(wq);
wq_free_lockdep(wq);
free_workqueue_attrs(wq->unbound_attrs);
kfree(wq);
return NULL;