From 584c5c422f6c749ced1e0bc3c6837f650f64e1e1 Mon Sep 17 00:00:00 2001 From: Rui Wang Date: Wed, 17 Aug 2016 16:00:34 +0800 Subject: [PATCH] x86/ioapic: Support hot-removal of IOAPICs present during boot IOAPICs present during system boot aren't added to ioapic_list, thus are unable to be hot-removed. Fix it by calling acpi_ioapic_add() during root bus enumeration. Signed-off-by: Rui Wang Acked-by: Bjorn Helgaas Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: helgaas@kernel.org Cc: linux-acpi@vger.kernel.org Cc: linux-pci@vger.kernel.org Cc: rjw@rjwysocki.net Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1471420837-31003-3-git-send-email-rui.y.wang@intel.com Signed-off-by: Ingo Molnar --- drivers/acpi/pci_root.c | 10 ++++++++++ drivers/pci/setup-bus.c | 5 ++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index b07eda1e7b05..bf601d4df8cf 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -614,6 +614,16 @@ static int acpi_pci_root_add(struct acpi_device *device, if (hotadd) { pcibios_resource_survey_bus(root->bus); pci_assign_unassigned_root_bus_resources(root->bus); + /* + * This is only called for the hotadd case. For the boot-time + * case, we need to wait until after PCI initialization in + * order to deal with IOAPICs mapped in on a PCI BAR. + * + * This is currently x86-specific, because acpi_ioapic_add() + * is an empty function without CONFIG_ACPI_HOTPLUG_IOAPIC. + * And CONFIG_ACPI_HOTPLUG_IOAPIC depends on CONFIG_X86_IO_APIC + * (see drivers/acpi/Kconfig). + */ acpi_ioapic_add(root->device->handle); } diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index c74059e10a6d..ec538d3d2bd5 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -25,6 +25,7 @@ #include #include #include +#include #include "pci.h" unsigned int pci_flags; @@ -1852,8 +1853,10 @@ void __init pci_assign_unassigned_resources(void) { struct pci_bus *root_bus; - list_for_each_entry(root_bus, &pci_root_buses, node) + list_for_each_entry(root_bus, &pci_root_buses, node) { pci_assign_unassigned_root_bus_resources(root_bus); + acpi_ioapic_add(ACPI_HANDLE(root_bus->bridge)); + } } void pci_assign_unassigned_bridge_resources(struct pci_dev *bridge)