From 683058e315f00a216fd6c79df4f63bc9945ca434 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 3 May 2013 00:26:16 +0200 Subject: ACPI / hotplug: Use device offline/online for graceful hot-removal Modify the generic ACPI hotplug code to be able to check if devices scheduled for hot-removal may be gracefully removed from the system using the device offline/online mechanism introduced previously. Namely, make acpi_scan_hot_remove() handling device hot-removal call device_offline() for all physical companions of the ACPI device nodes involved in the operation and check the results. If any of the device_offline() calls fails, the function will not progress to the removal phase (which cannot be aborted), unless its (new) force argument is set (in case of a failing offline it will put the devices offlined by it back online). In support of 'forced' device hot-removal, add a new sysfs attribute 'force_remove' that will reside under /sys/firmware/acpi/hotplug/. Signed-off-by: Rafael J. Wysocki Reviewed-by: Toshi Kani --- drivers/acpi/internal.h | 2 ++ drivers/acpi/scan.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++ drivers/acpi/sysfs.c | 31 ++++++++++++++++++ 3 files changed, 117 insertions(+) (limited to 'drivers/acpi') diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 6f1afd9118c..4548f0a114c 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -47,6 +47,8 @@ void acpi_memory_hotplug_init(void); static inline void acpi_memory_hotplug_init(void) {} #endif +extern bool acpi_force_hot_remove; + void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug, const char *name); int acpi_scan_add_handler_with_hotplug(struct acpi_scan_handler *handler, diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index fe158fd4f1d..4fd392005ef 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -27,6 +27,12 @@ extern struct acpi_device *acpi_root; #define ACPI_IS_ROOT_DEVICE(device) (!(device)->parent) +/* + * If set, devices will be hot-removed even if they cannot be put offline + * gracefully (from the kernel's standpoint). + */ +bool acpi_force_hot_remove; + static const char *dummy_hid = "device"; static LIST_HEAD(acpi_device_list); @@ -120,6 +126,59 @@ acpi_device_modalias_show(struct device *dev, struct device_attribute *attr, cha } static DEVICE_ATTR(modalias, 0444, acpi_device_modalias_show, NULL); +static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl, + void *data, void **ret_p) +{ + struct acpi_device *device = NULL; + struct acpi_device_physical_node *pn; + acpi_status status = AE_OK; + + if (acpi_bus_get_device(handle, &device)) + return AE_OK; + + mutex_lock(&device->physical_node_lock); + + list_for_each_entry(pn, &device->physical_node_list, node) { + int ret; + + ret = device_offline(pn->dev); + if (acpi_force_hot_remove) + continue; + + if (ret < 0) { + status = AE_ERROR; + break; + } + pn->put_online = !ret; + } + + mutex_unlock(&device->physical_node_lock); + + return status; +} + +static acpi_status acpi_bus_online_companions(acpi_handle handle, u32 lvl, + void *data, void **ret_p) +{ + struct acpi_device *device = NULL; + struct acpi_device_physical_node *pn; + + if (acpi_bus_get_device(handle, &device)) + return AE_OK; + + mutex_lock(&device->physical_node_lock); + + list_for_each_entry(pn, &device->physical_node_list, node) + if (pn->put_online) { + device_online(pn->dev); + pn->put_online = false; + } + + mutex_unlock(&device->physical_node_lock); + + return AE_OK; +} + static int acpi_scan_hot_remove(struct acpi_device *device) { acpi_handle handle = device->handle; @@ -136,10 +195,33 @@ static int acpi_scan_hot_remove(struct acpi_device *device) return -EINVAL; } + lock_device_hotplug(); + + status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, + NULL, acpi_bus_offline_companions, NULL, + NULL); + if (ACPI_SUCCESS(status) || acpi_force_hot_remove) + status = acpi_bus_offline_companions(handle, 0, NULL, NULL); + + if (ACPI_FAILURE(status) && !acpi_force_hot_remove) { + acpi_bus_online_companions(handle, 0, NULL, NULL); + acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, + acpi_bus_online_companions, NULL, NULL, + NULL); + + unlock_device_hotplug(); + + put_device(&device->dev); + return -EBUSY; + } + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Hot-removing device %s...\n", dev_name(&device->dev))); acpi_bus_trim(device); + + unlock_device_hotplug(); + /* Device node has been unregistered. */ put_device(&device->dev); device = NULL; @@ -236,6 +318,7 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source) int error; mutex_lock(&acpi_scan_lock); + lock_device_hotplug(); acpi_bus_get_device(handle, &device); if (device) { @@ -259,6 +342,7 @@ static void acpi_scan_bus_device_check(acpi_handle handle, u32 ost_source) kobject_uevent(&device->dev.kobj, KOBJ_ONLINE); out: + unlock_device_hotplug(); acpi_evaluate_hotplug_ost(handle, ost_source, ost_code, NULL); mutex_unlock(&acpi_scan_lock); } diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index fcae5fa2e1b..5c5d1624fa2 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -780,6 +780,33 @@ void acpi_sysfs_add_hotplug_profile(struct acpi_hotplug_profile *hotplug, pr_err(PREFIX "Unable to add hotplug profile '%s'\n", name); } +static ssize_t force_remove_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", !!acpi_force_hot_remove); +} + +static ssize_t force_remove_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t size) +{ + bool val; + int ret; + + ret = strtobool(buf, &val); + if (ret < 0) + return ret; + + lock_device_hotplug(); + acpi_force_hot_remove = val; + unlock_device_hotplug(); + return size; +} + +static const struct kobj_attribute force_remove_attr = + __ATTR(force_remove, S_IRUGO | S_IWUSR, force_remove_show, + force_remove_store); + int __init acpi_sysfs_init(void) { int result; @@ -789,6 +816,10 @@ int __init acpi_sysfs_init(void) return result; hotplug_kobj = kobject_create_and_add("hotplug", acpi_kobj); + result = sysfs_create_file(hotplug_kobj, &force_remove_attr.attr); + if (result) + return result; + result = sysfs_create_file(acpi_kobj, &pm_profile_attr.attr); return result; } -- cgit v1.2.3 From ac212b6980d8d5eda705864fc5a8ecddc6d6eacc Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 3 May 2013 00:26:22 +0200 Subject: ACPI / processor: Use common hotplug infrastructure Split the ACPI processor driver into two parts, one that is non-modular, resides in the ACPI core and handles the enumeration and hotplug of processors and one that implements the rest of the existing processor driver functionality. The non-modular part uses an ACPI scan handler object to enumerate processors on the basis of information provided by the ACPI namespace and to hook up with the common ACPI hotplug infrastructure. It also populates the ACPI handle of each processor device having a corresponding object in the ACPI namespace, which allows the driver proper to bind to those devices, and makes the driver bind to them if it is readily available (i.e. loaded) when the scan handler's .attach() routine is running. There are a few reasons to make this change. First, switching the ACPI processor driver to using the common ACPI hotplug infrastructure reduces code duplication and size considerably, even though a new file is created along with a header comment etc. Second, since the common hotplug code attempts to offline devices before starting the (non-reversible) removal procedure, it will abort (and possibly roll back) hot-remove operations involving processors if cpu_down() returns an error code for one of them instead of continuing them blindly (if /sys/firmware/acpi/hotplug/force_remove is unset). That is a more desirable behavior than what the current code does. Finally, the separation of the scan/hotplug part from the driver proper makes it possible to simplify the driver's .remove() routine, because it doesn't need to worry about the possible cleanup related to processor removal any more (the scan/hotplug part is responsible for that now) and can handle device removal and driver removal symmetricaly (i.e. as appropriate). Some user-visible changes in sysfs are made (for example, the 'sysdev' link from the ACPI device node to the processor device's directory is gone and a 'physical_node' link is present instead and a corresponding 'firmware_node' is present in the processor device's directory, the processor driver is now visible under /sys/bus/cpu/drivers/ and bound to the processor device), but that shouldn't affect the functionality that users care about (frequency scaling, C-states and thermal management). Tested on my venerable Toshiba Portege R500. Signed-off-by: Rafael J. Wysocki Acked-by: Greg Kroah-Hartman Reviewed-by: Toshi Kani --- drivers/acpi/Makefile | 1 + drivers/acpi/acpi_processor.c | 484 ++++++++++++++++++++++++ drivers/acpi/glue.c | 6 +- drivers/acpi/internal.h | 3 + drivers/acpi/processor_driver.c | 807 ++++------------------------------------ drivers/acpi/scan.c | 1 + 6 files changed, 571 insertions(+), 731 deletions(-) create mode 100644 drivers/acpi/acpi_processor.c (limited to 'drivers/acpi') diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index ecb743bf05a..93e49bde31b 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -34,6 +34,7 @@ acpi-$(CONFIG_ACPI_SLEEP) += proc.o acpi-y += bus.o glue.o acpi-y += scan.o acpi-y += resource.o +acpi-y += acpi_processor.o acpi-y += processor_core.o acpi-y += ec.o acpi-$(CONFIG_ACPI_DOCK) += dock.o diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c new file mode 100644 index 00000000000..587d2af4b32 --- /dev/null +++ b/drivers/acpi/acpi_processor.c @@ -0,0 +1,484 @@ +/* + * acpi_processor.c - ACPI processor enumeration support + * + * Copyright (C) 2001, 2002 Andy Grover + * Copyright (C) 2001, 2002 Paul Diefenbaugh + * Copyright (C) 2004 Dominik Brodowski + * Copyright (C) 2004 Anil S Keshavamurthy + * Copyright (C) 2013, Intel Corporation + * Rafael J. Wysocki + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include + +#include + +#include + +#include "internal.h" + +#define _COMPONENT ACPI_PROCESSOR_COMPONENT + +ACPI_MODULE_NAME("processor"); + +/* -------------------------------------------------------------------------- + Errata Handling + -------------------------------------------------------------------------- */ + +struct acpi_processor_errata errata __read_mostly; +EXPORT_SYMBOL_GPL(errata); + +static int acpi_processor_errata_piix4(struct pci_dev *dev) +{ + u8 value1 = 0; + u8 value2 = 0; + + + if (!dev) + return -EINVAL; + + /* + * Note that 'dev' references the PIIX4 ACPI Controller. + */ + + switch (dev->revision) { + case 0: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); + break; + case 1: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); + break; + case 2: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); + break; + case 3: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); + break; + default: + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); + break; + } + + switch (dev->revision) { + + case 0: /* PIIX4 A-step */ + case 1: /* PIIX4 B-step */ + /* + * See specification changes #13 ("Manual Throttle Duty Cycle") + * and #14 ("Enabling and Disabling Manual Throttle"), plus + * erratum #5 ("STPCLK# Deassertion Time") from the January + * 2002 PIIX4 specification update. Applies to only older + * PIIX4 models. + */ + errata.piix4.throttle = 1; + + case 2: /* PIIX4E */ + case 3: /* PIIX4M */ + /* + * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA + * Livelock") from the January 2002 PIIX4 specification update. + * Applies to all PIIX4 models. + */ + + /* + * BM-IDE + * ------ + * Find the PIIX4 IDE Controller and get the Bus Master IDE + * Status register address. We'll use this later to read + * each IDE controller's DMA status to make sure we catch all + * DMA activity. + */ + dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, + PCI_DEVICE_ID_INTEL_82371AB, + PCI_ANY_ID, PCI_ANY_ID, NULL); + if (dev) { + errata.piix4.bmisx = pci_resource_start(dev, 4); + pci_dev_put(dev); + } + + /* + * Type-F DMA + * ---------- + * Find the PIIX4 ISA Controller and read the Motherboard + * DMA controller's status to see if Type-F (Fast) DMA mode + * is enabled (bit 7) on either channel. Note that we'll + * disable C3 support if this is enabled, as some legacy + * devices won't operate well if fast DMA is disabled. + */ + dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, + PCI_DEVICE_ID_INTEL_82371AB_0, + PCI_ANY_ID, PCI_ANY_ID, NULL); + if (dev) { + pci_read_config_byte(dev, 0x76, &value1); + pci_read_config_byte(dev, 0x77, &value2); + if ((value1 & 0x80) || (value2 & 0x80)) + errata.piix4.fdma = 1; + pci_dev_put(dev); + } + + break; + } + + if (errata.piix4.bmisx) + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Bus master activity detection (BM-IDE) erratum enabled\n")); + if (errata.piix4.fdma) + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Type-F DMA livelock erratum (C3 disabled)\n")); + + return 0; +} + +static int acpi_processor_errata(struct acpi_processor *pr) +{ + int result = 0; + struct pci_dev *dev = NULL; + + + if (!pr) + return -EINVAL; + + /* + * PIIX4 + */ + dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, + PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, + PCI_ANY_ID, NULL); + if (dev) { + result = acpi_processor_errata_piix4(dev); + pci_dev_put(dev); + } + + return result; +} + +/* -------------------------------------------------------------------------- + Initialization + -------------------------------------------------------------------------- */ + +#ifdef CONFIG_ACPI_HOTPLUG_CPU +static int acpi_processor_hotadd_init(struct acpi_processor *pr) +{ + unsigned long long sta; + acpi_status status; + int ret; + + status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta); + if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT)) + return -ENODEV; + + ret = acpi_map_lsapic(pr->handle, &pr->id); + if (ret) + return ret; + + ret = arch_register_cpu(pr->id); + if (ret) { + acpi_unmap_lsapic(pr->id); + return ret; + } + + /* + * CPU got hot-added, but cpu_data is not initialized yet. Set a flag + * to delay cpu_idle/throttling initialization and do it when the CPU + * gets online for the first time. + */ + pr_info("CPU%d has been hot-added\n", pr->id); + pr->flags.need_hotplug_init = 1; + return 0; +} +#else +static inline int acpi_processor_hotadd_init(struct acpi_processor *pr) +{ + return -ENODEV; +} +#endif /* CONFIG_ACPI_HOTPLUG_CPU */ + +static int acpi_processor_get_info(struct acpi_device *device) +{ + union acpi_object object = { 0 }; + struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; + struct acpi_processor *pr = acpi_driver_data(device); + int cpu_index, device_declaration = 0; + acpi_status status = AE_OK; + static int cpu0_initialized; + + if (num_online_cpus() > 1) + errata.smp = TRUE; + + acpi_processor_errata(pr); + + /* + * Check to see if we have bus mastering arbitration control. This + * is required for proper C3 usage (to maintain cache coherency). + */ + if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { + pr->flags.bm_control = 1; + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "Bus mastering arbitration control present\n")); + } else + ACPI_DEBUG_PRINT((ACPI_DB_INFO, + "No bus mastering arbitration control\n")); + + if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { + /* Declared with "Processor" statement; match ProcessorID */ + status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer); + if (ACPI_FAILURE(status)) { + dev_err(&device->dev, + "Failed to evaluate processor object (0x%x)\n", + status); + return -ENODEV; + } + + /* + * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP. + * >>> 'acpi_get_processor_id(acpi_id, &id)' in + * arch/xxx/acpi.c + */ + pr->acpi_id = object.processor.proc_id; + } else { + /* + * Declared with "Device" statement; match _UID. + * Note that we don't handle string _UIDs yet. + */ + unsigned long long value; + status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, + NULL, &value); + if (ACPI_FAILURE(status)) { + dev_err(&device->dev, + "Failed to evaluate processor _UID (0x%x)\n", + status); + return -ENODEV; + } + device_declaration = 1; + pr->acpi_id = value; + } + cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id); + + /* Handle UP system running SMP kernel, with no LAPIC in MADT */ + if (!cpu0_initialized && (cpu_index == -1) && + (num_online_cpus() == 1)) { + cpu_index = 0; + } + + cpu0_initialized = 1; + + pr->id = cpu_index; + + /* + * Extra Processor objects may be enumerated on MP systems with + * less than the max # of CPUs. They should be ignored _iff + * they are physically not present. + */ + if (pr->id == -1) { + int ret = acpi_processor_hotadd_init(pr); + if (ret) + return ret; + } + /* + * On some boxes several processors use the same processor bus id. + * But they are located in different scope. For example: + * \_SB.SCK0.CPU0 + * \_SB.SCK1.CPU0 + * Rename the processor device bus id. And the new bus id will be + * generated as the following format: + * CPU+CPU ID. + */ + sprintf(acpi_device_bid(device), "CPU%X", pr->id); + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, + pr->acpi_id)); + + if (!object.processor.pblk_address) + ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); + else if (object.processor.pblk_length != 6) + dev_err(&device->dev, "Invalid PBLK length [%d]\n", + object.processor.pblk_length); + else { + pr->throttling.address = object.processor.pblk_address; + pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset; + pr->throttling.duty_width = acpi_gbl_FADT.duty_width; + + pr->pblk = object.processor.pblk_address; + + /* + * We don't care about error returns - we just try to mark + * these reserved so that nobody else is confused into thinking + * that this region might be unused.. + * + * (In particular, allocating the IO range for Cardbus) + */ + request_region(pr->throttling.address, 6, "ACPI CPU throttle"); + } + + /* + * If ACPI describes a slot number for this CPU, we can use it to + * ensure we get the right value in the "physical id" field + * of /proc/cpuinfo + */ + status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer); + if (ACPI_SUCCESS(status)) + arch_fix_phys_package_id(pr->id, object.integer.value); + + return 0; +} + +/* + * Do not put anything in here which needs the core to be online. + * For example MSR access or setting up things which check for cpuinfo_x86 + * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. + * Such things have to be put in and set up by the processor driver's .probe(). + */ +static DEFINE_PER_CPU(void *, processor_device_array); + +static int __cpuinit acpi_processor_add(struct acpi_device *device, + const struct acpi_device_id *id) +{ + struct acpi_processor *pr; + struct device *dev; + int result = 0; + + pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); + if (!pr) + return -ENOMEM; + + if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) { + result = -ENOMEM; + goto err_free_pr; + } + + pr->handle = device->handle; + strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); + strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); + device->driver_data = pr; + + result = acpi_processor_get_info(device); + if (result) /* Processor is not physically present or unavailable */ + return 0; + +#ifdef CONFIG_SMP + if (pr->id >= setup_max_cpus && pr->id != 0) + return 0; +#endif + + BUG_ON(pr->id >= nr_cpu_ids); + + /* + * Buggy BIOS check. + * ACPI id of processors can be reported wrongly by the BIOS. + * Don't trust it blindly + */ + if (per_cpu(processor_device_array, pr->id) != NULL && + per_cpu(processor_device_array, pr->id) != device) { + dev_warn(&device->dev, + "BIOS reported wrong ACPI id %d for the processor\n", + pr->id); + /* Give up, but do not abort the namespace scan. */ + goto err; + } + /* + * processor_device_array is not cleared on errors to allow buggy BIOS + * checks. + */ + per_cpu(processor_device_array, pr->id) = device; + + dev = get_cpu_device(pr->id); + ACPI_HANDLE_SET(dev, pr->handle); + result = acpi_bind_one(dev, NULL); + if (result) + goto err; + + pr->dev = dev; + dev->offline = pr->flags.need_hotplug_init; + + /* Trigger the processor driver's .probe() if present. */ + if (device_attach(dev) >= 0) + return 1; + + dev_err(dev, "Processor driver could not be attached\n"); + acpi_unbind_one(dev); + + err: + free_cpumask_var(pr->throttling.shared_cpu_map); + device->driver_data = NULL; + err_free_pr: + kfree(pr); + return result; +} + +#ifdef CONFIG_ACPI_HOTPLUG_CPU +/* -------------------------------------------------------------------------- + Removal + -------------------------------------------------------------------------- */ + +static void acpi_processor_remove(struct acpi_device *device) +{ + struct acpi_processor *pr; + + if (!device || !acpi_driver_data(device)) + return; + + pr = acpi_driver_data(device); + if (pr->id >= nr_cpu_ids) + goto out; + + /* + * The only reason why we ever get here is CPU hot-removal. The CPU is + * already offline and the ACPI device removal locking prevents it from + * being put back online at this point. + * + * Unbind the driver from the processor device and detach it from the + * ACPI companion object. + */ + device_release_driver(pr->dev); + acpi_unbind_one(pr->dev); + + /* Clean up. */ + per_cpu(processor_device_array, pr->id) = NULL; + try_offline_node(cpu_to_node(pr->id)); + + /* Remove the CPU. */ + get_online_cpus(); + arch_unregister_cpu(pr->id); + acpi_unmap_lsapic(pr->id); + put_online_cpus(); + + out: + free_cpumask_var(pr->throttling.shared_cpu_map); + kfree(pr); +} +#endif /* CONFIG_ACPI_HOTPLUG_CPU */ + +/* + * The following ACPI IDs are known to be suitable for representing as + * processor devices. + */ +static const struct acpi_device_id processor_device_ids[] = { + + { ACPI_PROCESSOR_OBJECT_HID, }, + { ACPI_PROCESSOR_DEVICE_HID, }, + + { } +}; + +static struct acpi_scan_handler __refdata processor_handler = { + .ids = processor_device_ids, + .attach = acpi_processor_add, +#ifdef CONFIG_ACPI_HOTPLUG_CPU + .detach = acpi_processor_remove, +#endif + .hotplug = { + .enabled = true, + }, +}; + +void __init acpi_processor_init(void) +{ + acpi_scan_add_handler_with_hotplug(&processor_handler, "processor"); +} diff --git a/drivers/acpi/glue.c b/drivers/acpi/glue.c index 40a84cc6740..9783f400d85 100644 --- a/drivers/acpi/glue.c +++ b/drivers/acpi/glue.c @@ -105,7 +105,7 @@ acpi_handle acpi_get_child(acpi_handle parent, u64 address) } EXPORT_SYMBOL(acpi_get_child); -static int acpi_bind_one(struct device *dev, acpi_handle handle) +int acpi_bind_one(struct device *dev, acpi_handle handle) { struct acpi_device *acpi_dev; acpi_status status; @@ -188,8 +188,9 @@ static int acpi_bind_one(struct device *dev, acpi_handle handle) kfree(physical_node); goto err; } +EXPORT_SYMBOL_GPL(acpi_bind_one); -static int acpi_unbind_one(struct device *dev) +int acpi_unbind_one(struct device *dev) { struct acpi_device_physical_node *entry; struct acpi_device *acpi_dev; @@ -238,6 +239,7 @@ err: dev_err(dev, "Oops, 'acpi_handle' corrupt\n"); return -EINVAL; } +EXPORT_SYMBOL_GPL(acpi_unbind_one); static int acpi_platform_notify(struct device *dev) { diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 4548f0a114c..bf792595132 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -33,6 +33,7 @@ static inline void acpi_pci_slot_init(void) { } void acpi_pci_root_init(void); void acpi_pci_link_init(void); void acpi_pci_root_hp_init(void); +void acpi_processor_init(void); void acpi_platform_init(void); int acpi_sysfs_init(void); void acpi_csrt_init(void); @@ -79,6 +80,8 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle, int type, unsigned long long sta); void acpi_device_add_finalize(struct acpi_device *device); void acpi_free_pnp_ids(struct acpi_device_pnp *pnp); +int acpi_bind_one(struct device *dev, acpi_handle handle); +int acpi_unbind_one(struct device *dev); /* -------------------------------------------------------------------------- Power Resource diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index c266cdc1178..ac28f18823b 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -1,11 +1,13 @@ /* - * acpi_processor.c - ACPI Processor Driver ($Revision: 71 $) + * processor_driver.c - ACPI Processor Driver * * Copyright (C) 2001, 2002 Andy Grover * Copyright (C) 2001, 2002 Paul Diefenbaugh * Copyright (C) 2004 Dominik Brodowski * Copyright (C) 2004 Anil S Keshavamurthy * - Added processor hotplug support + * Copyright (C) 2013, Intel Corporation + * Rafael J. Wysocki * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * @@ -24,52 +26,29 @@ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - * TBD: - * 1. Make # power states dynamic. - * 2. Support duty_cycle values that span bit 4. - * 3. Optimize by having scheduler determine business instead of - * having us try to calculate it here. - * 4. Need C1 timing -- must modify kernel (IRQ handler) to get this. */ #include #include #include -#include -#include -#include #include #include -#include -#include #include #include #include -#include - -#include -#include -#include -#include -#include -#include -#include - -#include -#include + #include +#include "internal.h" + #define PREFIX "ACPI: " -#define ACPI_PROCESSOR_CLASS "processor" -#define ACPI_PROCESSOR_DEVICE_NAME "Processor" #define ACPI_PROCESSOR_FILE_INFO "info" #define ACPI_PROCESSOR_FILE_THROTTLING "throttling" #define ACPI_PROCESSOR_FILE_LIMIT "limit" #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 #define ACPI_PROCESSOR_NOTIFY_POWER 0x81 #define ACPI_PROCESSOR_NOTIFY_THROTTLING 0x82 -#define ACPI_PROCESSOR_DEVICE_HID "ACPI0007" #define ACPI_PROCESSOR_LIMIT_USER 0 #define ACPI_PROCESSOR_LIMIT_THERMAL 1 @@ -81,12 +60,8 @@ MODULE_AUTHOR("Paul Diefenbaugh"); MODULE_DESCRIPTION("ACPI Processor Driver"); MODULE_LICENSE("GPL"); -static int acpi_processor_add(struct acpi_device *device); -static int acpi_processor_remove(struct acpi_device *device); -static void acpi_processor_notify(struct acpi_device *device, u32 event); -static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr); -static int acpi_processor_handle_eject(struct acpi_processor *pr); -static int acpi_processor_start(struct acpi_processor *pr); +static int acpi_processor_start(struct device *dev); +static int acpi_processor_stop(struct device *dev); static const struct acpi_device_id processor_device_ids[] = { {ACPI_PROCESSOR_OBJECT_HID, 0}, @@ -95,295 +70,27 @@ static const struct acpi_device_id processor_device_ids[] = { }; MODULE_DEVICE_TABLE(acpi, processor_device_ids); -static struct acpi_driver acpi_processor_driver = { +static struct device_driver acpi_processor_driver = { .name = "processor", - .class = ACPI_PROCESSOR_CLASS, - .ids = processor_device_ids, - .ops = { - .add = acpi_processor_add, - .remove = acpi_processor_remove, - .notify = acpi_processor_notify, - }, + .bus = &cpu_subsys, + .acpi_match_table = processor_device_ids, + .probe = acpi_processor_start, + .remove = acpi_processor_stop, }; -#define INSTALL_NOTIFY_HANDLER 1 -#define UNINSTALL_NOTIFY_HANDLER 2 - DEFINE_PER_CPU(struct acpi_processor *, processors); EXPORT_PER_CPU_SYMBOL(processors); -struct acpi_processor_errata errata __read_mostly; - -/* -------------------------------------------------------------------------- - Errata Handling - -------------------------------------------------------------------------- */ - -static int acpi_processor_errata_piix4(struct pci_dev *dev) +static void acpi_processor_notify(acpi_handle handle, u32 event, void *data) { - u8 value1 = 0; - u8 value2 = 0; - - - if (!dev) - return -EINVAL; - - /* - * Note that 'dev' references the PIIX4 ACPI Controller. - */ - - switch (dev->revision) { - case 0: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); - break; - case 1: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); - break; - case 2: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); - break; - case 3: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); - break; - default: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); - break; - } - - switch (dev->revision) { - - case 0: /* PIIX4 A-step */ - case 1: /* PIIX4 B-step */ - /* - * See specification changes #13 ("Manual Throttle Duty Cycle") - * and #14 ("Enabling and Disabling Manual Throttle"), plus - * erratum #5 ("STPCLK# Deassertion Time") from the January - * 2002 PIIX4 specification update. Applies to only older - * PIIX4 models. - */ - errata.piix4.throttle = 1; - - case 2: /* PIIX4E */ - case 3: /* PIIX4M */ - /* - * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA - * Livelock") from the January 2002 PIIX4 specification update. - * Applies to all PIIX4 models. - */ - - /* - * BM-IDE - * ------ - * Find the PIIX4 IDE Controller and get the Bus Master IDE - * Status register address. We'll use this later to read - * each IDE controller's DMA status to make sure we catch all - * DMA activity. - */ - dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, - PCI_DEVICE_ID_INTEL_82371AB, - PCI_ANY_ID, PCI_ANY_ID, NULL); - if (dev) { - errata.piix4.bmisx = pci_resource_start(dev, 4); - pci_dev_put(dev); - } - - /* - * Type-F DMA - * ---------- - * Find the PIIX4 ISA Controller and read the Motherboard - * DMA controller's status to see if Type-F (Fast) DMA mode - * is enabled (bit 7) on either channel. Note that we'll - * disable C3 support if this is enabled, as some legacy - * devices won't operate well if fast DMA is disabled. - */ - dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, - PCI_DEVICE_ID_INTEL_82371AB_0, - PCI_ANY_ID, PCI_ANY_ID, NULL); - if (dev) { - pci_read_config_byte(dev, 0x76, &value1); - pci_read_config_byte(dev, 0x77, &value2); - if ((value1 & 0x80) || (value2 & 0x80)) - errata.piix4.fdma = 1; - pci_dev_put(dev); - } - - break; - } - - if (errata.piix4.bmisx) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Bus master activity detection (BM-IDE) erratum enabled\n")); - if (errata.piix4.fdma) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Type-F DMA livelock erratum (C3 disabled)\n")); - - return 0; -} - -static int acpi_processor_errata(struct acpi_processor *pr) -{ - int result = 0; - struct pci_dev *dev = NULL; - - - if (!pr) - return -EINVAL; - - /* - * PIIX4 - */ - dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, - PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, - PCI_ANY_ID, NULL); - if (dev) { - result = acpi_processor_errata_piix4(dev); - pci_dev_put(dev); - } - - return result; -} - -/* -------------------------------------------------------------------------- - Driver Interface - -------------------------------------------------------------------------- */ - -static int acpi_processor_get_info(struct acpi_device *device) -{ - acpi_status status = 0; - union acpi_object object = { 0 }; - struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; + struct acpi_device *device = data; struct acpi_processor *pr; - int cpu_index, device_declaration = 0; - static int cpu0_initialized; - - pr = acpi_driver_data(device); - if (!pr) - return -EINVAL; - - if (num_online_cpus() > 1) - errata.smp = TRUE; - - acpi_processor_errata(pr); - - /* - * Check to see if we have bus mastering arbitration control. This - * is required for proper C3 usage (to maintain cache coherency). - */ - if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { - pr->flags.bm_control = 1; - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Bus mastering arbitration control present\n")); - } else - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "No bus mastering arbitration control\n")); - - if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { - /* Declared with "Processor" statement; match ProcessorID */ - status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer); - if (ACPI_FAILURE(status)) { - dev_err(&device->dev, - "Failed to evaluate processor object (0x%x)\n", - status); - return -ENODEV; - } - - /* - * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP. - * >>> 'acpi_get_processor_id(acpi_id, &id)' in - * arch/xxx/acpi.c - */ - pr->acpi_id = object.processor.proc_id; - } else { - /* - * Declared with "Device" statement; match _UID. - * Note that we don't handle string _UIDs yet. - */ - unsigned long long value; - status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, - NULL, &value); - if (ACPI_FAILURE(status)) { - dev_err(&device->dev, - "Failed to evaluate processor _UID (0x%x)\n", - status); - return -ENODEV; - } - device_declaration = 1; - pr->acpi_id = value; - } - cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id); - - /* Handle UP system running SMP kernel, with no LAPIC in MADT */ - if (!cpu0_initialized && (cpu_index == -1) && - (num_online_cpus() == 1)) { - cpu_index = 0; - } - - cpu0_initialized = 1; - - pr->id = cpu_index; - - /* - * Extra Processor objects may be enumerated on MP systems with - * less than the max # of CPUs. They should be ignored _iff - * they are physically not present. - */ - if (pr->id == -1) { - if (ACPI_FAILURE(acpi_processor_hotadd_init(pr))) - return -ENODEV; - } - /* - * On some boxes several processors use the same processor bus id. - * But they are located in different scope. For example: - * \_SB.SCK0.CPU0 - * \_SB.SCK1.CPU0 - * Rename the processor device bus id. And the new bus id will be - * generated as the following format: - * CPU+CPU ID. - */ - sprintf(acpi_device_bid(device), "CPU%X", pr->id); - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, - pr->acpi_id)); - - if (!object.processor.pblk_address) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); - else if (object.processor.pblk_length != 6) - dev_err(&device->dev, "Invalid PBLK length [%d]\n", - object.processor.pblk_length); - else { - pr->throttling.address = object.processor.pblk_address; - pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset; - pr->throttling.duty_width = acpi_gbl_FADT.duty_width; - - pr->pblk = object.processor.pblk_address; - - /* - * We don't care about error returns - we just try to mark - * these reserved so that nobody else is confused into thinking - * that this region might be unused.. - * - * (In particular, allocating the IO range for Cardbus) - */ - request_region(pr->throttling.address, 6, "ACPI CPU throttle"); - } - - /* - * If ACPI describes a slot number for this CPU, we can use it - * ensure we get the right value in the "physical id" field - * of /proc/cpuinfo - */ - status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer); - if (ACPI_SUCCESS(status)) - arch_fix_phys_package_id(pr->id, object.integer.value); - - return 0; -} - -static DEFINE_PER_CPU(void *, processor_device_array); - -static void acpi_processor_notify(struct acpi_device *device, u32 event) -{ - struct acpi_processor *pr = acpi_driver_data(device); int saved; + if (device->handle != handle) + return; + + pr = acpi_driver_data(device); if (!pr) return; @@ -420,55 +127,62 @@ static void acpi_processor_notify(struct acpi_device *device, u32 event) return; } -static int acpi_cpu_soft_notify(struct notifier_block *nfb, - unsigned long action, void *hcpu) +static __cpuinit int __acpi_processor_start(struct acpi_device *device); + +static int __cpuinit acpi_cpu_soft_notify(struct notifier_block *nfb, + unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; struct acpi_processor *pr = per_cpu(processors, cpu); + struct acpi_device *device; - if (action == CPU_ONLINE && pr) { - /* CPU got physically hotplugged and onlined the first time: - * Initialize missing things + if (!pr || acpi_bus_get_device(pr->handle, &device)) + return NOTIFY_DONE; + + if (action == CPU_ONLINE) { + /* + * CPU got physically hotplugged and onlined for the first time: + * Initialize missing things. */ if (pr->flags.need_hotplug_init) { + int ret; + pr_info("Will online and init hotplugged CPU: %d\n", pr->id); - WARN(acpi_processor_start(pr), "Failed to start CPU:" - " %d\n", pr->id); pr->flags.need_hotplug_init = 0; - /* Normal CPU soft online event */ + ret = __acpi_processor_start(device); + WARN(ret, "Failed to start CPU: %d\n", pr->id); } else { + /* Normal CPU soft online event. */ acpi_processor_ppc_has_changed(pr, 0); acpi_processor_hotplug(pr); acpi_processor_reevaluate_tstate(pr, action); acpi_processor_tstate_has_changed(pr); } - } - if (action == CPU_DEAD && pr) { - /* invalidate the flag.throttling after one CPU is offline */ + } else if (action == CPU_DEAD) { + /* Invalidate flag.throttling after the CPU is offline. */ acpi_processor_reevaluate_tstate(pr, action); } return NOTIFY_OK; } -static struct notifier_block acpi_cpu_notifier = +static struct notifier_block __refdata acpi_cpu_notifier = { .notifier_call = acpi_cpu_soft_notify, }; -/* - * acpi_processor_start() is called by the cpu_hotplug_notifier func: - * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the - * root cause seem to be that acpi_processor_uninstall_hotplug_notify() - * is in the module_exit (__exit) func. Allowing acpi_processor_start() - * to not be in __cpuinit section, but being called from __cpuinit funcs - * via __ref looks like the right thing to do here. - */ -static __ref int acpi_processor_start(struct acpi_processor *pr) +static __cpuinit int __acpi_processor_start(struct acpi_device *device) { - struct acpi_device *device = per_cpu(processor_device_array, pr->id); + struct acpi_processor *pr = acpi_driver_data(device); + acpi_status status; int result = 0; + if (!pr) + return -ENODEV; + + if (pr->flags.need_hotplug_init) + return 0; + #ifdef CONFIG_CPU_FREQ acpi_processor_ppc_has_changed(pr, 0); acpi_processor_load_module(pr); @@ -506,129 +220,48 @@ static __ref int acpi_processor_start(struct acpi_processor *pr) goto err_remove_sysfs_thermal; } - return 0; + status = acpi_install_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, + acpi_processor_notify, device); + if (ACPI_SUCCESS(status)) + return 0; -err_remove_sysfs_thermal: + sysfs_remove_link(&pr->cdev->device.kobj, "device"); + err_remove_sysfs_thermal: sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); -err_thermal_unregister: + err_thermal_unregister: thermal_cooling_device_unregister(pr->cdev); -err_power_exit: + err_power_exit: acpi_processor_power_exit(pr); - return result; } -/* - * Do not put anything in here which needs the core to be online. - * For example MSR access or setting up things which check for cpuinfo_x86 - * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. - * Such things have to be put in and set up above in acpi_processor_start() - */ -static int __cpuinit acpi_processor_add(struct acpi_device *device) +static int __cpuinit acpi_processor_start(struct device *dev) { - struct acpi_processor *pr = NULL; - int result = 0; - struct device *dev; - - pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); - if (!pr) - return -ENOMEM; + struct acpi_device *device; - if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) { - result = -ENOMEM; - goto err_free_pr; - } - - pr->handle = device->handle; - strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); - strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); - device->driver_data = pr; - - result = acpi_processor_get_info(device); - if (result) { - /* Processor is physically not present */ - return 0; - } - -#ifdef CONFIG_SMP - if (pr->id >= setup_max_cpus && pr->id != 0) - return 0; -#endif - - BUG_ON(pr->id >= nr_cpu_ids); - - /* - * Buggy BIOS check - * ACPI id of processors can be reported wrongly by the BIOS. - * Don't trust it blindly - */ - if (per_cpu(processor_device_array, pr->id) != NULL && - per_cpu(processor_device_array, pr->id) != device) { - dev_warn(&device->dev, - "BIOS reported wrong ACPI id %d for the processor\n", - pr->id); - result = -ENODEV; - goto err_free_cpumask; - } - per_cpu(processor_device_array, pr->id) = device; - - per_cpu(processors, pr->id) = pr; + if (acpi_bus_get_device(ACPI_HANDLE(dev), &device)) + return -ENODEV; - dev = get_cpu_device(pr->id); - if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) { - result = -EFAULT; - goto err_clear_processor; - } - - /* - * Do not start hotplugged CPUs now, but when they - * are onlined the first time - */ - if (pr->flags.need_hotplug_init) - return 0; - - result = acpi_processor_start(pr); - if (result) - goto err_remove_sysfs; - - return 0; - -err_remove_sysfs: - sysfs_remove_link(&device->dev.kobj, "sysdev"); -err_clear_processor: - /* - * processor_device_array is not cleared to allow checks for buggy BIOS - */ - per_cpu(processors, pr->id) = NULL; -err_free_cpumask: - free_cpumask_var(pr->throttling.shared_cpu_map); -err_free_pr: - kfree(pr); - return result; + return __acpi_processor_start(device); } -static int acpi_processor_remove(struct acpi_device *device) +static int acpi_processor_stop(struct device *dev) { - struct acpi_processor *pr = NULL; + struct acpi_device *device; + struct acpi_processor *pr; + if (acpi_bus_get_device(ACPI_HANDLE(dev), &device)) + return 0; - if (!device || !acpi_driver_data(device)) - return -EINVAL; + acpi_remove_notify_handler(device->handle, ACPI_DEVICE_NOTIFY, + acpi_processor_notify); pr = acpi_driver_data(device); - - if (pr->id >= nr_cpu_ids) - goto free; - - if (device->removal_type == ACPI_BUS_REMOVAL_EJECT) { - if (acpi_processor_handle_eject(pr)) - return -EINVAL; - } + if (!pr) + return 0; acpi_processor_power_exit(pr); - sysfs_remove_link(&device->dev.kobj, "sysdev"); - if (pr->cdev) { sysfs_remove_link(&device->dev.kobj, "thermal_cooling"); sysfs_remove_link(&pr->cdev->device.kobj, "device"); @@ -637,331 +270,47 @@ static int acpi_processor_remove(struct acpi_device *device) } per_cpu(processors, pr->id) = NULL; - per_cpu(processor_device_array, pr->id) = NULL; - try_offline_node(cpu_to_node(pr->id)); - -free: - free_cpumask_var(pr->throttling.shared_cpu_map); - kfree(pr); - return 0; } -#ifdef CONFIG_ACPI_HOTPLUG_CPU -/**************************************************************************** - * Acpi processor hotplug support * - ****************************************************************************/ - -static int is_processor_present(acpi_handle handle) -{ - acpi_status status; - unsigned long long sta = 0; - - - status = acpi_evaluate_integer(handle, "_STA", NULL, &sta); - - if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT)) - return 1; - - /* - * _STA is mandatory for a processor that supports hot plug - */ - if (status == AE_NOT_FOUND) - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Processor does not support hot plug\n")); - else - ACPI_EXCEPTION((AE_INFO, status, - "Processor Device is not present")); - return 0; -} - -static void acpi_processor_hotplug_notify(acpi_handle handle, - u32 event, void *data) -{ - struct acpi_device *device = NULL; - struct acpi_eject_event *ej_event = NULL; - u32 ost_code = ACPI_OST_SC_NON_SPECIFIC_FAILURE; /* default */ - acpi_status status; - int result; - - acpi_scan_lock_acquire(); - - switch (event) { - case ACPI_NOTIFY_BUS_CHECK: - case ACPI_NOTIFY_DEVICE_CHECK: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Processor driver received %s event\n", - (event == ACPI_NOTIFY_BUS_CHECK) ? - "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK")); - - if (!is_processor_present(handle)) - break; - - if (!acpi_bus_get_device(handle, &device)) - break; - - result = acpi_bus_scan(handle); - if (result) { - acpi_handle_err(handle, "Unable to add the device\n"); - break; - } - result = acpi_bus_get_device(handle, &device); - if (result) { - acpi_handle_err(handle, "Missing device object\n"); - break; - } - ost_code = ACPI_OST_SC_SUCCESS; - break; - - case ACPI_NOTIFY_EJECT_REQUEST: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "received ACPI_NOTIFY_EJECT_REQUEST\n")); - - if (acpi_bus_get_device(handle, &device)) { - acpi_handle_err(handle, - "Device don't exist, dropping EJECT\n"); - break; - } - if (!acpi_driver_data(device)) { - acpi_handle_err(handle, - "Driver data is NULL, dropping EJECT\n"); - break; - } - - ej_event = kmalloc(sizeof(*ej_event), GFP_KERNEL); - if (!ej_event) { - acpi_handle_err(handle, "No memory, dropping EJECT\n"); - break; - } - - get_device(&device->dev); - ej_event->device = device; - ej_event->event = ACPI_NOTIFY_EJECT_REQUEST; - /* The eject is carried out asynchronously. */ - status = acpi_os_hotplug_execute(acpi_bus_hot_remove_device, - ej_event); - if (ACPI_FAILURE(status)) { - put_device(&device->dev); - kfree(ej_event); - break; - } - goto out; - - default: - ACPI_DEBUG_PRINT((ACPI_DB_INFO, - "Unsupported event [0x%x]\n", event)); - - /* non-hotplug event; possibly handled by other handler */ - goto out; - } - - /* Inform firmware that the hotplug operation has completed */ - (void) acpi_evaluate_hotplug_ost(handle, event, ost_code, NULL); - - out: - acpi_scan_lock_release(); -} - -static acpi_status is_processor_device(acpi_handle handle) -{ - struct acpi_device_info *info; - char *hid; - acpi_status status; - - status = acpi_get_object_info(handle, &info); - if (ACPI_FAILURE(status)) - return status; - - if (info->type == ACPI_TYPE_PROCESSOR) { - kfree(info); - return AE_OK; /* found a processor object */ - } - - if (!(info->valid & ACPI_VALID_HID)) { - kfree(info); - return AE_ERROR; - } - - hid = info->hardware_id.string; - if ((hid == NULL) || strcmp(hid, ACPI_PROCESSOR_DEVICE_HID)) { - kfree(info); - return AE_ERROR; - } - - kfree(info); - return AE_OK; /* found a processor device object */ -} - -static acpi_status -processor_walk_namespace_cb(acpi_handle handle, - u32 lvl, void *context, void **rv) -{ - acpi_status status; - int *action = context; - - status = is_processor_device(handle); - if (ACPI_FAILURE(status)) - return AE_OK; /* not a processor; continue to walk */ - - switch (*action) { - case INSTALL_NOTIFY_HANDLER: - acpi_install_notify_handler(handle, - ACPI_SYSTEM_NOTIFY, - acpi_processor_hotplug_notify, - NULL); - break; - case UNINSTALL_NOTIFY_HANDLER: - acpi_remove_notify_handler(handle, - ACPI_SYSTEM_NOTIFY, - acpi_processor_hotplug_notify); - break; - default: - break; - } - - /* found a processor; skip walking underneath */ - return AE_CTRL_DEPTH; -} - -static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) -{ - acpi_handle handle = pr->handle; - - if (!is_processor_present(handle)) { - return AE_ERROR; - } - - if (acpi_map_lsapic(handle, &pr->id)) - return AE_ERROR; - - if (arch_register_cpu(pr->id)) { - acpi_unmap_lsapic(pr->id); - return AE_ERROR; - } - - /* CPU got hot-plugged, but cpu_data is not initialized yet - * Set flag to delay cpu_idle/throttling initialization - * in: - * acpi_processor_add() - * acpi_processor_get_info() - * and do it when the CPU gets online the first time - * TBD: Cleanup above functions and try to do this more elegant. - */ - pr_info("CPU %d got hotplugged\n", pr->id); - pr->flags.need_hotplug_init = 1; - - return AE_OK; -} - -static int acpi_processor_handle_eject(struct acpi_processor *pr) -{ - if (cpu_online(pr->id)) - cpu_down(pr->id); - - get_online_cpus(); - /* - * The cpu might become online again at this point. So we check whether - * the cpu has been onlined or not. If the cpu became online, it means - * that someone wants to use the cpu. So acpi_processor_handle_eject() - * returns -EAGAIN. - */ - if (unlikely(cpu_online(pr->id))) { - put_online_cpus(); - pr_warn("Failed to remove CPU %d, because other task " - "brought the CPU back online\n", pr->id); - return -EAGAIN; - } - arch_unregister_cpu(pr->id); - acpi_unmap_lsapic(pr->id); - put_online_cpus(); - return (0); -} -#else -static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr) -{ - return AE_ERROR; -} -static int acpi_processor_handle_eject(struct acpi_processor *pr) -{ - return (-EINVAL); -} -#endif - -static -void acpi_processor_install_hotplug_notify(void) -{ -#ifdef CONFIG_ACPI_HOTPLUG_CPU - int action = INSTALL_NOTIFY_HANDLER; - acpi_walk_namespace(ACPI_TYPE_ANY, - ACPI_ROOT_OBJECT, - ACPI_UINT32_MAX, - processor_walk_namespace_cb, NULL, &action, NULL); -#endif - register_hotcpu_notifier(&acpi_cpu_notifier); -} - -static -void acpi_processor_uninstall_hotplug_notify(void) -{ -#ifdef CONFIG_ACPI_HOTPLUG_CPU - int action = UNINSTALL_NOTIFY_HANDLER; - acpi_walk_namespace(ACPI_TYPE_ANY, - ACPI_ROOT_OBJECT, - ACPI_UINT32_MAX, - processor_walk_namespace_cb, NULL, &action, NULL); -#endif - unregister_hotcpu_notifier(&acpi_cpu_notifier); -} - /* * We keep the driver loaded even when ACPI is not running. * This is needed for the powernow-k8 driver, that works even without * ACPI, but needs symbols from this driver */ -static int __init acpi_processor_init(void) +static int __init acpi_processor_driver_init(void) { int result = 0; if (acpi_disabled) return 0; - result = acpi_bus_register_driver(&acpi_processor_driver); + result = driver_register(&acpi_processor_driver); if (result < 0) return result; acpi_processor_syscore_init(); - - acpi_processor_install_hotplug_notify(); - + register_hotcpu_notifier(&acpi_cpu_notifier); acpi_thermal_cpufreq_init(); - acpi_processor_ppc_init(); - acpi_processor_throttling_init(); - return 0; } -static void __exit acpi_processor_exit(void) +static void __exit acpi_processor_driver_exit(void) { if (acpi_disabled) return; acpi_processor_ppc_exit(); - acpi_thermal_cpufreq_exit(); - - acpi_processor_uninstall_hotplug_notify(); - + unregister_hotcpu_notifier(&acpi_cpu_notifier); acpi_processor_syscore_exit(); - - acpi_bus_unregister_driver(&acpi_processor_driver); - - return; + driver_unregister(&acpi_processor_driver); } -module_init(acpi_processor_init); -module_exit(acpi_processor_exit); +module_init(acpi_processor_driver_init); +module_exit(acpi_processor_driver_exit); MODULE_ALIAS("processor"); diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 4fd392005ef..ad82bb2a37e 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -2124,6 +2124,7 @@ int __init acpi_scan_init(void) acpi_pci_root_init(); acpi_pci_link_init(); + acpi_processor_init(); acpi_platform_init(); acpi_lpss_init(); acpi_csrt_init(); -- cgit v1.2.3 From e2ff39400d81233374e780b133496a2296643d7d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 8 May 2013 00:29:49 +0200 Subject: ACPI / memhotplug: Bind removable memory blocks to ACPI device nodes During ACPI memory hotplug configuration bind memory blocks residing in modules removable through the standard ACPI mechanism to struct acpi_device objects associated with ACPI namespace objects representing those modules. Accordingly, unbind those memory blocks from the struct acpi_device objects when the memory modules in question are being removed. When "offline" operation for devices representing memory blocks is introduced, this will allow the ACPI core's device hot-remove code to use it to carry out remove_memory() for those memory blocks and check the results of that before it actually removes the modules holding them from the system. Since walk_memory_range() is used for accessing all memory blocks corresponding to a given ACPI namespace object, it is exported from memory_hotplug.c so that the code in acpi_memhotplug.c can use it. Signed-off-by: Rafael J. Wysocki Tested-by: Vasilis Liaskovitis Reviewed-by: Toshi Kani --- drivers/acpi/acpi_memhotplug.c | 53 +++++++++++++++++++++++++++++++++++++++--- 1 file changed, 50 insertions(+), 3 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c index 5e6301e9492..5590db12028 100644 --- a/drivers/acpi/acpi_memhotplug.c +++ b/drivers/acpi/acpi_memhotplug.c @@ -28,6 +28,7 @@ */ #include +#include #include #include "internal.h" @@ -166,13 +167,50 @@ static int acpi_memory_check_device(struct acpi_memory_device *mem_device) return 0; } +static unsigned long acpi_meminfo_start_pfn(struct acpi_memory_info *info) +{ + return PFN_DOWN(info->start_addr); +} + +static unsigned long acpi_meminfo_end_pfn(struct acpi_memory_info *info) +{ + return PFN_UP(info->start_addr + info->length-1); +} + +static int acpi_bind_memblk(struct memory_block *mem, void *arg) +{ + return acpi_bind_one(&mem->dev, (acpi_handle)arg); +} + +static int acpi_bind_memory_blocks(struct acpi_memory_info *info, + acpi_handle handle) +{ + return walk_memory_range(acpi_meminfo_start_pfn(info), + acpi_meminfo_end_pfn(info), (void *)handle, + acpi_bind_memblk); +} + +static int acpi_unbind_memblk(struct memory_block *mem, void *arg) +{ + acpi_unbind_one(&mem->dev); + return 0; +} + +static void acpi_unbind_memory_blocks(struct acpi_memory_info *info, + acpi_handle handle) +{ + walk_memory_range(acpi_meminfo_start_pfn(info), + acpi_meminfo_end_pfn(info), NULL, acpi_unbind_memblk); +} + static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) { + acpi_handle handle = mem_device->device->handle; int result, num_enabled = 0; struct acpi_memory_info *info; int node; - node = acpi_get_node(mem_device->device->handle); + node = acpi_get_node(handle); /* * Tell the VM there is more memory here... * Note: Assume that this function returns zero on success @@ -203,6 +241,12 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) if (result && result != -EEXIST) continue; + result = acpi_bind_memory_blocks(info, handle); + if (result) { + acpi_unbind_memory_blocks(info, handle); + return -ENODEV; + } + info->enabled = 1; /* @@ -229,10 +273,11 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) { + acpi_handle handle = mem_device->device->handle; int result = 0, nid; struct acpi_memory_info *info, *n; - nid = acpi_get_node(mem_device->device->handle); + nid = acpi_get_node(handle); list_for_each_entry_safe(info, n, &mem_device->res_list, list) { if (!info->enabled) @@ -240,6 +285,8 @@ static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) if (nid < 0) nid = memory_add_physaddr_to_nid(info->start_addr); + + acpi_unbind_memory_blocks(info, handle); result = remove_memory(nid, info->start_addr, info->length); if (result) return result; @@ -300,7 +347,7 @@ static int acpi_memory_device_add(struct acpi_device *device, if (result) { dev_err(&device->dev, "acpi_memory_enable_device() error\n"); acpi_memory_device_free(mem_device); - return -ENODEV; + return result; } dev_dbg(&device->dev, "Memory device configured by ACPI\n"); -- cgit v1.2.3 From 2e4f1db49d97222110b6add9a2c6cf5251a41e35 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 30 May 2013 21:55:46 +0200 Subject: ACPI / processor: Initialize per_cpu(processors, pr->id) properly Commit ac212b6 (ACPI / processor: Use common hotplug infrastructure) forgot about initializing the per-CPU 'processors' variables which lead to ACPI cpuidle failure to use C-states and caused boot slowdown on multi-CPU machines. Fix the problem by adding per_cpu(processors, pr->id) initialization to acpi_processor_add() and add make acpi_processor_remove() clean it up as appropriate. Also modify acpi_processor_stop() so that it doesn't clear per_cpu(processors, pr->id) on processor driver removal which would then cause problems to happen when the driver is loaded again. This version of the patch contains fixes from Yinghai Lu. Reported-and-tested-by: Yinghai Lu Reported-and-tested-by: Daniel Lezcano Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_processor.c | 6 ++++++ drivers/acpi/processor_driver.c | 5 ----- 2 files changed, 6 insertions(+), 5 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index 587d2af4b32..cae2641e8d8 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -29,6 +29,9 @@ ACPI_MODULE_NAME("processor"); +DEFINE_PER_CPU(struct acpi_processor *, processors); +EXPORT_PER_CPU_SYMBOL(processors); + /* -------------------------------------------------------------------------- Errata Handling -------------------------------------------------------------------------- */ @@ -387,6 +390,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device, * checks. */ per_cpu(processor_device_array, pr->id) = device; + per_cpu(processors, pr->id) = pr; dev = get_cpu_device(pr->id); ACPI_HANDLE_SET(dev, pr->handle); @@ -407,6 +411,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device, err: free_cpumask_var(pr->throttling.shared_cpu_map); device->driver_data = NULL; + per_cpu(processors, pr->id) = NULL; err_free_pr: kfree(pr); return result; @@ -441,6 +446,7 @@ static void acpi_processor_remove(struct acpi_device *device) /* Clean up. */ per_cpu(processor_device_array, pr->id) = NULL; + per_cpu(processors, pr->id) = NULL; try_offline_node(cpu_to_node(pr->id)); /* Remove the CPU. */ diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index ac28f18823b..d93963f1e8f 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -78,9 +78,6 @@ static struct device_driver acpi_processor_driver = { .remove = acpi_processor_stop, }; -DEFINE_PER_CPU(struct acpi_processor *, processors); -EXPORT_PER_CPU_SYMBOL(processors); - static void acpi_processor_notify(acpi_handle handle, u32 event, void *data) { struct acpi_device *device = data; @@ -268,8 +265,6 @@ static int acpi_processor_stop(struct device *dev) thermal_cooling_device_unregister(pr->cdev); pr->cdev = NULL; } - - per_cpu(processors, pr->id) = NULL; return 0; } -- cgit v1.2.3 From 2e199192df85eb936a7829dc28b57b85c59c86fc Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 May 2013 10:40:35 +0200 Subject: ACPI: Drop removal_type field from struct acpi_device The ACPI processor driver was the only user of the removal_type field in struct acpi_device, but it doesn't use that field any more after recent changes. Thus, removal_type has no more users, so drop it along with the associated data type. Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani --- drivers/acpi/scan.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index ad82bb2a37e..ba8ee6cbf0f 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1036,7 +1036,6 @@ int acpi_device_add(struct acpi_device *device, printk(KERN_ERR PREFIX "Error creating sysfs interface for device %s\n", dev_name(&device->dev)); - device->removal_type = ACPI_BUS_REMOVAL_NORMAL; return 0; err: @@ -2025,7 +2024,6 @@ static acpi_status acpi_bus_device_detach(acpi_handle handle, u32 lvl_not_used, if (!acpi_bus_get_device(handle, &device)) { struct acpi_scan_handler *dev_handler = device->handler; - device->removal_type = ACPI_BUS_REMOVAL_EJECT; if (dev_handler) { if (dev_handler->detach) dev_handler->detach(device); -- cgit v1.2.3 From be547436c22c3b7d934d9afd841cfd7a6807f7ab Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 May 2013 10:40:56 +0200 Subject: ACPI / processor: Pass processor object handle to acpi_bind_one() Make acpi_processor_add() pass the ACPI handle of the processor namespace object to acpi_bind_one() instead of setting it directly to allow acpi_bind_one() to catch possible bugs causing the ACPI handle of the processor device to be set earlier. Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani --- drivers/acpi/acpi_processor.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index cae2641e8d8..157e7389a5f 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -393,8 +393,7 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device, per_cpu(processors, pr->id) = pr; dev = get_cpu_device(pr->id); - ACPI_HANDLE_SET(dev, pr->handle); - result = acpi_bind_one(dev, NULL); + result = acpi_bind_one(dev, pr->handle); if (result) goto err; -- cgit v1.2.3 From 303bfdb1a14d0460feb859cd008ff81da36b517c Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 May 2013 10:43:13 +0200 Subject: ACPI / scan: Add second pass of companion offlining to hot-remove code As indicated by comments in mm/memory_hotplug.c:remove_memory(), if CONFIG_MEMCG is set, it may not be possible to offline all of the memory blocks held by one module (FRU) in one pass (because one of them may be used by the others to store page cgroup in that case and that block has to be offlined before the other ones). To handle that arguably corner case, add a second pass of companion device offlining to acpi_scan_hot_remove() and make it ignore errors returned in the first pass (and make it skip the second pass if the first one is successful). Signed-off-by: Rafael J. Wysocki Acked-by: Toshi Kani --- drivers/acpi/scan.c | 71 +++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 52 insertions(+), 19 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index ba8ee6cbf0f..2959fe1ce43 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -131,6 +131,7 @@ static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl, { struct acpi_device *device = NULL; struct acpi_device_physical_node *pn; + bool second_pass = (bool)data; acpi_status status = AE_OK; if (acpi_bus_get_device(handle, &device)) @@ -141,15 +142,26 @@ static acpi_status acpi_bus_offline_companions(acpi_handle handle, u32 lvl, list_for_each_entry(pn, &device->physical_node_list, node) { int ret; + if (second_pass) { + /* Skip devices offlined by the first pass. */ + if (pn->put_online) + continue; + } else { + pn->put_online = false; + } ret = device_offline(pn->dev); if (acpi_force_hot_remove) continue; - if (ret < 0) { - status = AE_ERROR; - break; + if (ret >= 0) { + pn->put_online = !ret; + } else { + *ret_p = pn->dev; + if (second_pass) { + status = AE_ERROR; + break; + } } - pn->put_online = !ret; } mutex_unlock(&device->physical_node_lock); @@ -185,6 +197,7 @@ static int acpi_scan_hot_remove(struct acpi_device *device) acpi_handle not_used; struct acpi_object_list arg_list; union acpi_object arg; + struct device *errdev; acpi_status status; unsigned long long sta; @@ -197,22 +210,42 @@ static int acpi_scan_hot_remove(struct acpi_device *device) lock_device_hotplug(); - status = acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, - NULL, acpi_bus_offline_companions, NULL, - NULL); - if (ACPI_SUCCESS(status) || acpi_force_hot_remove) - status = acpi_bus_offline_companions(handle, 0, NULL, NULL); - - if (ACPI_FAILURE(status) && !acpi_force_hot_remove) { - acpi_bus_online_companions(handle, 0, NULL, NULL); + /* + * Carry out two passes here and ignore errors in the first pass, + * because if the devices in question are memory blocks and + * CONFIG_MEMCG is set, one of the blocks may hold data structures + * that the other blocks depend on, but it is not known in advance which + * block holds them. + * + * If the first pass is successful, the second one isn't needed, though. + */ + errdev = NULL; + acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, + NULL, acpi_bus_offline_companions, + (void *)false, (void **)&errdev); + acpi_bus_offline_companions(handle, 0, (void *)false, (void **)&errdev); + if (errdev) { + errdev = NULL; acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX, - acpi_bus_online_companions, NULL, NULL, - NULL); - - unlock_device_hotplug(); - - put_device(&device->dev); - return -EBUSY; + NULL, acpi_bus_offline_companions, + (void *)true , (void **)&errdev); + if (!errdev || acpi_force_hot_remove) + acpi_bus_offline_companions(handle, 0, (void *)true, + (void **)&errdev); + + if (errdev && !acpi_force_hot_remove) { + dev_warn(errdev, "Offline failed.\n"); + acpi_bus_online_companions(handle, 0, NULL, NULL); + acpi_walk_namespace(ACPI_TYPE_ANY, handle, + ACPI_UINT32_MAX, + acpi_bus_online_companions, NULL, + NULL, NULL); + + unlock_device_hotplug(); + + put_device(&device->dev); + return -EBUSY; + } } ACPI_DEBUG_PRINT((ACPI_DB_INFO, -- cgit v1.2.3 From 242831eb15a06fa4414eaa705fdc6dd432ab98d1 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 27 May 2013 12:58:46 +0200 Subject: Memory hotplug / ACPI: Simplify memory removal Now that the memory offlining should be taken care of by the companion device offlining code in acpi_scan_hot_remove(), the ACPI memory hotplug driver doesn't need to offline it in remove_memory() any more. Moreover, since the return value of remove_memory() is not used, it's better to make it be a void function and trigger a BUG() if the memory scheduled for removal is not offline. Change the code in accordance with the above observations. Signed-off-by: Rafael J. Wysocki Reviewed-by: Toshi Kani --- drivers/acpi/acpi_memhotplug.c | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c index 5590db12028..c711d114404 100644 --- a/drivers/acpi/acpi_memhotplug.c +++ b/drivers/acpi/acpi_memhotplug.c @@ -271,13 +271,11 @@ static int acpi_memory_enable_device(struct acpi_memory_device *mem_device) return 0; } -static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) +static void acpi_memory_remove_memory(struct acpi_memory_device *mem_device) { acpi_handle handle = mem_device->device->handle; - int result = 0, nid; struct acpi_memory_info *info, *n; - - nid = acpi_get_node(handle); + int nid = acpi_get_node(handle); list_for_each_entry_safe(info, n, &mem_device->res_list, list) { if (!info->enabled) @@ -287,15 +285,10 @@ static int acpi_memory_remove_memory(struct acpi_memory_device *mem_device) nid = memory_add_physaddr_to_nid(info->start_addr); acpi_unbind_memory_blocks(info, handle); - result = remove_memory(nid, info->start_addr, info->length); - if (result) - return result; - + remove_memory(nid, info->start_addr, info->length); list_del(&info->list); kfree(info); } - - return result; } static void acpi_memory_device_free(struct acpi_memory_device *mem_device) -- cgit v1.2.3 From 173a5a4c909789fcd57d00355d2237618a3824a4 Mon Sep 17 00:00:00 2001 From: Hanjun Guo Date: Fri, 31 May 2013 11:36:08 +0800 Subject: ACPI / processor: Fix potential NULL pointer dereference in acpi_processor_add() In acpi_processor_add(), get_cpu_device() may return NULL in some cases which is then passed to acpi_bind_one() and that will case a NULL pointer dereference to occur. Add a check to prevent that from happening. [rjw: Changelog] Signed-off-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki --- drivers/acpi/acpi_processor.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/acpi') diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index 157e7389a5f..e9b01e35ac3 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -393,6 +393,11 @@ static int __cpuinit acpi_processor_add(struct acpi_device *device, per_cpu(processors, pr->id) = pr; dev = get_cpu_device(pr->id); + if (!dev) { + result = -ENODEV; + goto err; + } + result = acpi_bind_one(dev, pr->handle); if (result) goto err; -- cgit v1.2.3