From: Amos Kong <kongjianjun@xxxxxxxxx> When we add a device with acpiphp, we enumerate all functions in the slot with pci_scan_slot(), regardless of whether they have associated ACPI methods such as _EJ0. When removing the device, we previously removed only the functions with those ACPI methods. This patch makes the remove symmetric with the add: we remove all functions in the slot, whether they have associated ACPI methods or not. With qemu-kvm and SeaBIOS, we can build a multi-function device where only function 0 has _EJ0 and _ADR (see bugzilla below). Removing and re-adding that device works correctly with Windows guests. This patch makes it also work in Linux guests. [bhelgaas: restructure loop iteration, pull out of slot->funcs loop] Reference: https://bugzilla.kernel.org/show_bug.cgi?id=43219 Signed-off-by: Amos Kong <kongjianjun@xxxxxxxxx> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> --- drivers/pci/hotplug/acpiphp_glue.c | 39 +++++++++++++++++++++++++++--------- 1 files changed, 29 insertions(+), 10 deletions(-) diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index c8f9991..9aff4f0 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -878,6 +878,21 @@ static void disable_bridges(struct pci_bus *bus) } } +/* return first device in slot, acquiring a reference on it */ +static struct pci_dev *dev_in_slot(struct acpiphp_slot *slot) +{ + struct pci_bus *bus = slot->bridge->pci_bus; + struct pci_dev *dev; + + down_read(&pci_bus_sem); + list_for_each_entry(dev, &bus->devices, bus_list) + if (PCI_SLOT(dev->devfn) == slot->device) + return pci_dev_get(dev); + up_read(&pci_bus_sem); + + return NULL; +} + /** * disable_device - disable a slot * @slot: ACPI PHP slot @@ -902,18 +917,22 @@ static int disable_device(struct acpiphp_slot *slot) (u32)1, NULL, NULL); func->bridge = NULL; } + } - pdev = pci_get_slot(slot->bridge->pci_bus, - PCI_DEVFN(slot->device, func->function)); - if (pdev) { - pci_stop_bus_device(pdev); - if (pdev->subordinate) { - disable_bridges(pdev->subordinate); - pci_disable_device(pdev); - } - __pci_remove_bus_device(pdev); - pci_dev_put(pdev); + /* + * enable_device() enumerates all functions in this device via + * pci_scan_slot(), whether they have associated ACPI hotplug + * methods (_EJ0, etc.) or not. Therefore, we remove all functions + * here. + */ + while ((pdev = dev_in_slot(slot))) { + pci_stop_bus_device(pdev); + if (pdev->subordinate) { + disable_bridges(pdev->subordinate); + pci_disable_device(pdev); } + __pci_remove_bus_device(pdev); + pci_dev_put(pdev); } list_for_each_entry(func, &slot->funcs, sibling) { -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
