diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 7c2d9d596258..a6111140755c 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -302,9 +302,8 @@ struct drv_dev_and_id { const struct pci_device_id *id; }; -static long local_pci_probe(void *_ddi) +static int local_pci_probe(struct drv_dev_and_id *ddi) { - struct drv_dev_and_id *ddi = _ddi; struct pci_dev *pci_dev = ddi->dev; struct pci_driver *pci_drv = ddi->drv; struct device *dev = &pci_dev->dev; @@ -338,6 +337,19 @@ static long local_pci_probe(void *_ddi) return 0; } +struct pci_probe_arg { + struct drv_dev_and_id *ddi; + struct work_struct work; + int ret; +}; + +static void local_pci_probe_callback(struct work_struct *work) +{ + struct pci_probe_arg *arg = container_of(work, struct pci_probe_arg, work); + + arg->ret = local_pci_probe(arg->ddi); +} + static bool pci_physfn_is_probed(struct pci_dev *dev) { #ifdef CONFIG_PCI_IOV @@ -362,34 +374,51 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, dev->is_probed = 1; cpu_hotplug_disable(); - /* * Prevent nesting work_on_cpu() for the case where a Virtual Function * device is probed from work_on_cpu() of the Physical device. */ if (node < 0 || node >= MAX_NUMNODES || !node_online(node) || pci_physfn_is_probed(dev)) { - cpu = nr_cpu_ids; + error = local_pci_probe(&ddi); } else { cpumask_var_t wq_domain_mask; + struct pci_probe_arg arg = { .ddi = &ddi }; if (!zalloc_cpumask_var(&wq_domain_mask, GFP_KERNEL)) { error = -ENOMEM; goto out; } + + INIT_WORK_ONSTACK(&arg.work, local_pci_probe_callback); + + /* + * The target election and the enqueue of the work must be within + * the same RCU read side section so that when the workqueue pool + * is flushed after a housekeeping cpumask update, further readers + * are guaranteed to queue the probing work to the appropriate + * targets. + */ + rcu_read_lock(); cpumask_and(wq_domain_mask, housekeeping_cpumask(HK_TYPE_WQ), housekeeping_cpumask(HK_TYPE_DOMAIN)); cpu = cpumask_any_and(cpumask_of_node(node), wq_domain_mask); - free_cpumask_var(wq_domain_mask); - } + if (cpu < nr_cpu_ids) { + schedule_work_on(cpu, &arg.work); + rcu_read_unlock(); + flush_work(&arg.work); + error = arg.ret; + } else { + rcu_read_unlock(); + error = local_pci_probe(&ddi); + } - if (cpu < nr_cpu_ids) - error = work_on_cpu(cpu, local_pci_probe, &ddi); - else - error = local_pci_probe(&ddi); + free_cpumask_var(wq_domain_mask); + destroy_work_on_stack(&arg.work); + } out: dev->is_probed = 0; cpu_hotplug_enable();