On Wed, Jul 27, 2016 at 12:13:14AM +0800, Rui Wang wrote:
> 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 <rui.y.w...@intel.com>
> ---
> drivers/acpi/internal.h | 2 --
> drivers/acpi/ioapic.c | 7 ++++---
> drivers/acpi/pci_root.c | 13 ++++++++++++-
> drivers/pci/setup-bus.c | 5 ++++-
> include/linux/acpi.h | 6 ++++++
> 5 files changed, 26 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
> index 27cc7fe..6d8e67e 100644
> --- a/drivers/acpi/internal.h
> +++ b/drivers/acpi/internal.h
> @@ -40,10 +40,8 @@ int acpi_sysfs_init(void);
> void acpi_container_init(void);
> void acpi_memory_hotplug_init(void);
> #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
> -int acpi_ioapic_add(struct acpi_pci_root *root);
> int acpi_ioapic_remove(struct acpi_pci_root *root);
> #else
> -static inline int acpi_ioapic_add(struct acpi_pci_root *root) { return 0; }
It would be nicer if the interface change and header file munging
were in a separate patch so they wouldn't obscure the meat of the
change, i.e., the addition of calls to acpi_ioapic_add().
> static inline int acpi_ioapic_remove(struct acpi_pci_root *root) { return 0;
> }
> #endif
> #ifdef CONFIG_ACPI_DOCK
> diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c
> index ccdc8db..0f272e2 100644
> --- a/drivers/acpi/ioapic.c
> +++ b/drivers/acpi/ioapic.c
> @@ -189,16 +189,17 @@ exit:
> return AE_OK;
> }
>
> -int acpi_ioapic_add(struct acpi_pci_root *root)
> +int acpi_ioapic_add(acpi_handle root_handle)
> {
> acpi_status status, retval = AE_OK;
>
> - status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root->device->handle,
> + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root_handle,
> UINT_MAX, handle_ioapic_add, NULL,
> - root->device->handle, (void **)&retval);
> + root_handle, (void **)&retval);
>
> return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV;
> }
> +EXPORT_SYMBOL_GPL(acpi_ioapic_add);
What loadable module needs to call this? It shouldn't be exported
unless there is such a module.
> int acpi_ioapic_remove(struct acpi_pci_root *root)
> {
> diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
> index ae3fe4e..d818c61 100644
> --- a/drivers/acpi/pci_root.c
> +++ b/drivers/acpi/pci_root.c
> @@ -614,7 +614,18 @@ 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);
> - acpi_ioapic_add(root);
> +
> + /*
> + * 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);
> }
>
> pci_lock_rescan_remove();
> diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
> index 55641a3..e32c356 100644
> --- a/drivers/pci/setup-bus.c
> +++ b/drivers/pci/setup-bus.c
> @@ -25,6 +25,7 @@
> #include <linux/ioport.h>
> #include <linux/cache.h>
> #include <linux/slab.h>
> +#include <linux/acpi.h>
> #include "pci.h"
>
> unsigned int pci_flags;
> @@ -1779,8 +1780,10 @@ 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)
> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
> index 288fac5..f5114dc 100644
> --- a/include/linux/acpi.h
> +++ b/include/linux/acpi.h
> @@ -680,6 +680,12 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct
> acpi_device *adev)
>
> #endif /* !CONFIG_ACPI */
>
> +#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
> +int acpi_ioapic_add(acpi_handle root);
> +#else
> +static inline int acpi_ioapic_add(acpi_handle root) { return 0; }
> +#endif
> +
> #ifdef CONFIG_ACPI
> void acpi_os_set_prepare_sleep(int (*func)(u8 sleep_state,
> u32 pm1a_ctrl, u32 pm1b_ctrl));
> --
> 1.8.3.1
>
