Commit f92d74c1f5afaff7cd1ea14ade8f1ba6b519e422
Committed by
Bjorn Helgaas
Bjorn Helgaas
1 parent
fbeeb822f6
Exists in
smarc-imx_3.14.28_1.0.0_ga
and in
1 other branch
PCI: Warn on driver probe return value greater than zero
Ages ago, drivers could return values greater than zero from their probe function and this would be regarded as success. But after f3ec4f87d607 ("PCI: change device runtime PM settings for probe and remove") and 967577b06241 ("PCI/PM: Keep runtime PM enabled for unbound PCI devices"), we set dev->driver to NULL if the driver's probe function returns a value greater than zero. __pci_device_probe() treats this as success, and drivers can still mostly work even with dev->driver == NULL, but PCI power management doesn't work, and we don't call the driver's remove function on rmmod. To help catch these driver problems, issue a warning in this case. [bhelgaas: changelog] Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Showing 1 changed file with 10 additions and 2 deletions Side-by-side Diff
drivers/pci/pci-driver.c
| ... | ... | @@ -264,11 +264,19 @@ |
| 264 | 264 | pm_runtime_get_sync(dev); |
| 265 | 265 | pci_dev->driver = pci_drv; |
| 266 | 266 | rc = pci_drv->probe(pci_dev, ddi->id); |
| 267 | - if (rc) { | |
| 267 | + if (!rc) | |
| 268 | + return rc; | |
| 269 | + if (rc < 0) { | |
| 268 | 270 | pci_dev->driver = NULL; |
| 269 | 271 | pm_runtime_put_sync(dev); |
| 272 | + return rc; | |
| 270 | 273 | } |
| 271 | - return rc; | |
| 274 | + /* | |
| 275 | + * Probe function should return < 0 for failure, 0 for success | |
| 276 | + * Treat values > 0 as success, but warn. | |
| 277 | + */ | |
| 278 | + dev_warn(dev, "Driver probe function unexpectedly returned %d\n", rc); | |
| 279 | + return 0; | |
| 272 | 280 | } |
| 273 | 281 | |
| 274 | 282 | static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, |