From 25be162001ca6cb85b904597f8d340dc66dec843 Mon Sep 17 00:00:00 2001 From: "Stephen M. Cameron" Date: Tue, 5 Nov 2013 16:55:14 +1100 Subject: [PATCH] drivers/pci/pci-driver.c: 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. Commit f3ec4f87d607f40497 "PCI: change device runtime PM settings for probe and remove" slightly altered this in 2010, and commit 967577b062417b4e4b8e27b ("PCI/PM: Keep runtime PM enabled for unbound PCI devices") in late 2012 altered it more signficantly, setting pci_dev->driver to NULL if the driver's probe function returned a value greater than zero, which would for example prevent the driver's remove function from being called on rmmod. Neither of those changes would necessarily make the driver fail in an obvious way though, and so at least a couple drivers (cciss, hpsa) fell into this hole since they were returning 1, and this situation went unnoticed for quite some time. If a driver's probe function returns a value greater than zero, issue a warning, but otherwise treat this as success. Signed-off-by: Stephen M. Cameron Cc: Bjorn Helgaas Cc: Jens Axboe Cc: Greg KH Signed-off-by: Andrew Morton --- drivers/pci/pci-driver.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 98f7b9b89507..7fbe343b1408 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -264,11 +264,19 @@ static long local_pci_probe(void *_ddi) pm_runtime_get_sync(dev); pci_dev->driver = pci_drv; rc = pci_drv->probe(pci_dev, ddi->id); - if (rc) { + if (!rc) + return rc; + if (rc < 0) { pci_dev->driver = NULL; pm_runtime_put_sync(dev); + return rc; } - return rc; + /* + * Probe function should return < 0 for failure, 0 for success + * Treat values > 0 as success, but warn. + */ + dev_warn(dev, "Driver probe function unexpectedly returned %d\n", rc); + return 0; } static int pci_call_probe(struct pci_driver *drv, struct pci_dev *dev, -- 2.39.5