From e0217c5ba10d7bf640f038b2feae58e630f2f958 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Wed, 10 Nov 2021 12:03:34 -0600 Subject: Revert "PCI: Use to_pci_driver() instead of pci_dev->driver" MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This reverts commit 2a4d9408c9e8b6f6fc150c66f3fef755c9e20d4a. Robert reported a NULL pointer dereference caused by the PCI core (local_pci_probe()) calling the i2c_designware_pci driver's .runtime_resume() method before the .probe() method. i2c_dw_pci_resume() depends on initialization done by i2c_dw_pci_probe(). Prior to 2a4d9408c9e8 ("PCI: Use to_pci_driver() instead of pci_dev->driver"), pci_pm_runtime_resume() avoided calling the .runtime_resume() method because pci_dev->driver had not been set yet. 2a4d9408c9e8 and b5f9c644eb1b ("PCI: Remove struct pci_dev->driver"), removed pci_dev->driver, replacing it by device->driver, which *has* been set by this time, so pci_pm_runtime_resume() called the .runtime_resume() method when it previously had not. Fixes: 2a4d9408c9e8 ("PCI: Use to_pci_driver() instead of pci_dev->driver") Link: https://lore.kernel.org/linux-i2c/CAP145pgdrdiMAT7=-iB1DMgA7t_bMqTcJL4N0=6u8kNY3EU0dw@mail.gmail.com/ Reported-by: Robert Święcki Tested-by: Robert Święcki Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b88db815ee01..40012d13c3c4 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5123,14 +5123,13 @@ EXPORT_SYMBOL_GPL(pci_dev_unlock); static void pci_dev_save_and_disable(struct pci_dev *dev) { - struct pci_driver *drv = to_pci_driver(dev->dev.driver); const struct pci_error_handlers *err_handler = - drv ? drv->err_handler : NULL; + dev->driver ? dev->driver->err_handler : NULL; /* - * drv->err_handler->reset_prepare() is protected against races - * with ->remove() by the device lock, which must be held by the - * caller. + * dev->driver->err_handler->reset_prepare() is protected against + * races with ->remove() by the device lock, which must be held by + * the caller. */ if (err_handler && err_handler->reset_prepare) err_handler->reset_prepare(dev); @@ -5155,15 +5154,15 @@ static void pci_dev_save_and_disable(struct pci_dev *dev) static void pci_dev_restore(struct pci_dev *dev) { - struct pci_driver *drv = to_pci_driver(dev->dev.driver); const struct pci_error_handlers *err_handler = - drv ? drv->err_handler : NULL; + dev->driver ? dev->driver->err_handler : NULL; pci_restore_state(dev); /* - * drv->err_handler->reset_done() is protected against races with - * ->remove() by the device lock, which must be held by the caller. + * dev->driver->err_handler->reset_done() is protected against + * races with ->remove() by the device lock, which must be held by + * the caller. */ if (err_handler && err_handler->reset_done) err_handler->reset_done(dev); -- cgit v1.2.3-70-g09d2