diff options
| -rw-r--r-- | include/linux/workqueue.h | 5 | ||||
| -rw-r--r-- | kernel/workqueue.c | 18 |
2 files changed, 18 insertions, 5 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 2ebef6b1a3d6..74d3c1efd9bb 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -399,9 +399,8 @@ extern struct workqueue_struct *system_freezable_power_efficient_wq; * RETURNS: * Pointer to the allocated workqueue on success, %NULL on failure. */ -struct workqueue_struct *alloc_workqueue(const char *fmt, - unsigned int flags, - int max_active, ...); +__printf(1, 4) struct workqueue_struct * +alloc_workqueue(const char *fmt, unsigned int flags, int max_active, ...); /** * alloc_ordered_workqueue - allocate an ordered workqueue diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 33a6b4a2443d..1b3eb1e9531f 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -4830,8 +4830,16 @@ void show_workqueue_state(void) for_each_pwq(pwq, wq) { raw_spin_lock_irqsave(&pwq->pool->lock, flags); - if (pwq->nr_active || !list_empty(&pwq->inactive_works)) + if (pwq->nr_active || !list_empty(&pwq->inactive_works)) { + /* + * Defer printing to avoid deadlocks in console + * drivers that queue work while holding locks + * also taken in their write paths. + */ + printk_deferred_enter(); show_pwq(pwq); + printk_deferred_exit(); + } raw_spin_unlock_irqrestore(&pwq->pool->lock, flags); /* * We could be printing a lot from atomic context, e.g. @@ -4849,7 +4857,12 @@ void show_workqueue_state(void) raw_spin_lock_irqsave(&pool->lock, flags); if (pool->nr_workers == pool->nr_idle) goto next_pool; - + /* + * Defer printing to avoid deadlocks in console drivers that + * queue work while holding locks also taken in their write + * paths. + */ + printk_deferred_enter(); pr_info("pool %d:", pool->id); pr_cont_pool_info(pool); pr_cont(" hung=%us workers=%d", @@ -4864,6 +4877,7 @@ void show_workqueue_state(void) first = false; } pr_cont("\n"); + printk_deferred_exit(); next_pool: raw_spin_unlock_irqrestore(&pool->lock, flags); /* |