diff options
Diffstat (limited to 'drivers/pci/pci-driver.c')
| -rw-r--r-- | drivers/pci/pci-driver.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 9042fdbd7244..7edd5c307446 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -288,12 +288,27 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, int error, node; struct drv_dev_and_id ddi = { drv, dev, id }; - /* Execute driver initialization on node where the device's - bus is attached to. This way the driver likely allocates - its local memory on the right node without any need to - change it. */ + /* + * Execute driver initialization on node where the device is + * attached. This way the driver likely allocates its local memory + * on the right node. + */ node = dev_to_node(&dev->dev); - if (node >= 0) { + + /* + * On NUMA systems, we are likely to call a PF probe function using + * work_on_cpu(). If that probe calls pci_enable_sriov() (which + * adds the VF devices via pci_bus_add_device()), we may re-enter + * this function to call the VF probe function. Calling + * work_on_cpu() again will cause a lockdep warning. Since VFs are + * always on the same node as the PF, we can work around this by + * avoiding work_on_cpu() when we're already on the correct node. + * + * Preemption is enabled, so it's theoretically unsafe to use + * numa_node_id(), but even if we run the probe function on the + * wrong node, it should be functionally correct. + */ + if (node >= 0 && node != numa_node_id()) { int cpu; get_online_cpus(); @@ -305,6 +320,7 @@ static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, put_online_cpus(); } else error = local_pci_probe(&ddi); + return error; } |