From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> After relatively recent changes in the ACPI-based PCI hotplug (ACPIPHP) code, the acpiphp_check_host_bridge() executed for PCI host bridges via acpi_pci_root_scan_dependent() doesn't do anything useful, because those bridges do not have hotplug contexts. That happens by mistake, so fix it by making acpiphp_enumerate_slots() add hotplug contexts to PCI host bridges too and modify acpiphp_remove_slots() to drop those contexts for host bridges as appropriate. Link: https://bugzilla.kernel.org/show_bug.cgi?id=76901 Fixes: 2d8b1d566a5f (ACPI / hotplug / PCI: Get rid of check_sub_bridges()) Reported-and-tested-by: Gavin Guo <gavin.guo@xxxxxxxxxxxxx> Cc: 3.15+ <stable@xxxxxxxxxxxxxxx> # 3.15+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- drivers/pci/hotplug/acpiphp.h | 10 ++++++ drivers/pci/hotplug/acpiphp_glue.c | 60 +++++++++++++++++++++++++------------ 2 files changed, 52 insertions(+), 18 deletions(-) Index: linux-pm/drivers/pci/hotplug/acpiphp_glue.c =================================================================== --- linux-pm.orig/drivers/pci/hotplug/acpiphp_glue.c +++ linux-pm/drivers/pci/hotplug/acpiphp_glue.c @@ -373,17 +373,13 @@ static acpi_status acpiphp_add_context(a static struct acpiphp_bridge *acpiphp_dev_to_bridge(struct acpi_device *adev) { - struct acpiphp_context *context; struct acpiphp_bridge *bridge = NULL; acpi_lock_hp_context(); - context = acpiphp_get_context(adev); - if (context) { - bridge = context->bridge; + if (adev->hp) { + bridge = to_acpiphp_root_context(adev->hp)->root_bridge; if (bridge) get_bridge(bridge); - - acpiphp_put_context(context); } acpi_unlock_hp_context(); return bridge; @@ -881,7 +877,17 @@ void acpiphp_enumerate_slots(struct pci_ */ get_device(&bus->dev); - if (!pci_is_root_bus(bridge->pci_bus)) { + acpi_lock_hp_context(); + if (pci_is_root_bus(bridge->pci_bus)) { + struct acpiphp_root_context *root_context; + + root_context = kzalloc(sizeof(*root_context), GFP_KERNEL); + if (!root_context) + goto err; + + root_context->root_bridge = bridge; + acpi_set_hp_context(adev, &root_context->hp, NULL, NULL, NULL); + } else { struct acpiphp_context *context; /* @@ -890,21 +896,16 @@ void acpiphp_enumerate_slots(struct pci_ * parent is going to be handled by pciehp, in which case this * bridge is not interesting to us either. */ - acpi_lock_hp_context(); context = acpiphp_get_context(adev); - if (!context) { - acpi_unlock_hp_context(); - put_device(&bus->dev); - pci_dev_put(bridge->pci_dev); - kfree(bridge); - return; - } + if (!context) + goto err; + bridge->context = context; context->bridge = bridge; /* Get a reference to the parent bridge. */ get_bridge(context->func.parent); - acpi_unlock_hp_context(); } + acpi_unlock_hp_context(); /* Must be added to the list prior to calling acpiphp_add_context(). */ mutex_lock(&bridge_mutex); @@ -919,6 +920,30 @@ void acpiphp_enumerate_slots(struct pci_ cleanup_bridge(bridge); put_bridge(bridge); } + return; + + err: + acpi_unlock_hp_context(); + put_device(&bus->dev); + pci_dev_put(bridge->pci_dev); + kfree(bridge); +} + +void acpiphp_drop_bridge(struct acpiphp_bridge *bridge) +{ + if (pci_is_root_bus(bridge->pci_bus)) { + struct acpiphp_root_context *root_context; + struct acpi_device *adev; + + acpi_lock_hp_context(); + adev = ACPI_COMPANION(bridge->pci_bus->bridge); + root_context = to_acpiphp_root_context(adev->hp); + adev->hp = NULL; + acpi_unlock_hp_context(); + kfree(root_context); + } + cleanup_bridge(bridge); + put_bridge(bridge); } /** @@ -936,8 +961,7 @@ void acpiphp_remove_slots(struct pci_bus list_for_each_entry(bridge, &bridge_list, list) if (bridge->pci_bus == bus) { mutex_unlock(&bridge_mutex); - cleanup_bridge(bridge); - put_bridge(bridge); + acpiphp_drop_bridge(bridge); return; } Index: linux-pm/drivers/pci/hotplug/acpiphp.h =================================================================== --- linux-pm.orig/drivers/pci/hotplug/acpiphp.h +++ linux-pm/drivers/pci/hotplug/acpiphp.h @@ -142,6 +142,16 @@ static inline acpi_handle func_to_handle return func_to_acpi_device(func)->handle; } +struct acpiphp_root_context { + struct acpi_hotplug_context hp; + struct acpiphp_bridge *root_bridge; +}; + +static inline struct acpiphp_root_context *to_acpiphp_root_context(struct acpi_hotplug_context *hp) +{ + return container_of(hp, struct acpiphp_root_context, hp); +} + /* * struct acpiphp_attention_info - device specific attention registration * -- 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