From 94add0f82469fa3c4ff978d03a34da90813c819d Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Sun, 23 Jun 2013 00:59:55 +0200 Subject: ACPI / dock: Initialize ACPI dock subsystem upfront Commit 3b63aaa70e1 (PCI: acpiphp: Do not use ACPI PCI subdriver mechanism) introduced an ACPI dock support regression, because it changed the relative initialization order of the ACPI dock subsystem and the ACPI-based PCI hotplug (acpiphp). Namely, the ACPI dock subsystem has to be initialized before acpiphp_enumerate_slots() is first run, which after commit 3b63aaa70e1 happens during the initial enumeration of the PCI hierarchy triggered by the initial ACPI namespace scan in acpi_scan_init(). For this reason, the dock subsystem has to be initialized before the initial ACPI namespace scan in acpi_scan_init(). To make that happen, modify the ACPI dock subsystem to be non-modular and add the invocation of its initialization routine, acpi_dock_init(), to acpi_scan_init() directly before the initial namespace scan. [rjw: Changelog, removal of dock_exit().] References: https://bugzilla.kernel.org/show_bug.cgi?id=59501 Reported-and-tested-by: Alexander E. Patrakov Tested-by: Illya Klymov Signed-off-by: Jiang Liu Acked-by: Yinghai Lu Cc: 3.9+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/dock.c | 42 +----------------------------------------- drivers/acpi/internal.h | 5 +++++ drivers/acpi/scan.c | 1 + 3 files changed, 7 insertions(+), 41 deletions(-) (limited to 'drivers') diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c index ec117c6c996..c3b34f94382 100644 --- a/drivers/acpi/dock.c +++ b/drivers/acpi/dock.c @@ -993,30 +993,6 @@ err_unregister: return ret; } -/** - * dock_remove - free up resources related to the dock station - */ -static int dock_remove(struct dock_station *ds) -{ - struct dock_dependent_device *dd, *tmp; - struct platform_device *dock_device = ds->dock_device; - - if (!dock_station_count) - return 0; - - /* remove dependent devices */ - list_for_each_entry_safe(dd, tmp, &ds->dependent_devices, list) - kfree(dd); - - list_del(&ds->sibling); - - /* cleanup sysfs */ - sysfs_remove_group(&dock_device->dev.kobj, &dock_attribute_group); - platform_device_unregister(dock_device); - - return 0; -} - /** * find_dock_and_bay - look for dock stations and bays * @handle: acpi handle of a device @@ -1035,7 +1011,7 @@ find_dock_and_bay(acpi_handle handle, u32 lvl, void *context, void **rv) return AE_OK; } -static int __init dock_init(void) +int __init acpi_dock_init(void) { if (acpi_disabled) return 0; @@ -1054,19 +1030,3 @@ static int __init dock_init(void) ACPI_DOCK_DRIVER_DESCRIPTION, dock_station_count); return 0; } - -static void __exit dock_exit(void) -{ - struct dock_station *tmp, *dock_station; - - unregister_acpi_bus_notifier(&dock_acpi_notifier); - list_for_each_entry_safe(dock_station, tmp, &dock_stations, sibling) - dock_remove(dock_station); -} - -/* - * Must be called before drivers of devices in dock, otherwise we can't know - * which devices are in a dock - */ -subsys_initcall(dock_init); -module_exit(dock_exit); diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 297cbf456f8..c610a76d92c 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -40,6 +40,11 @@ void acpi_container_init(void); #else static inline void acpi_container_init(void) {} #endif +#ifdef CONFIG_ACPI_DOCK +void acpi_dock_init(void); +#else +static inline void acpi_dock_init(void) {} +#endif #ifdef CONFIG_ACPI_HOTPLUG_MEMORY void acpi_memory_hotplug_init(void); #else diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index b14ac46948c..27da63061e1 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -2042,6 +2042,7 @@ int __init acpi_scan_init(void) acpi_lpss_init(); acpi_container_init(); acpi_memory_hotplug_init(); + acpi_dock_init(); mutex_lock(&acpi_scan_lock); /* -- cgit v1.2.3 From d66ecb7220a70ec3f6c0e38e4af28fb8b25d31c6 Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Sun, 23 Jun 2013 01:01:35 +0200 Subject: PCI / ACPI: Use boot-time resource allocation rules during hotplug On x86 platforms, the kernel respects PCI resource assignments from the BIOS and only reassigns resources for unassigned BARs at boot time. However, with the ACPI-based hotplug (acpiphp), it ignores the BIOS' PCI resource assignments completely and reassigns all resources by itself. This causes differences in PCI resource allocation between boot time and runtime hotplug to occur, which is generally undesirable and sometimes actively breaks things. Namely, if there are enough resources, reassigning all PCI resources during runtime hotplug should work, but it may fail if the resources are constrained. This may happen, for instance, when some PCI devices with huge MMIO BARs are involved in the runtime hotplug operations, because the current PCI MMIO alignment algorithm may waste huge chunks of MMIO address space in those cases. On the Alexander's Sony VAIO VPCZ23A4R the BIOS allocates limited MMIO resources for the dock station which contains a device (graphics adapter) with a 256MB MMIO BAR. An attempt to reassign that during runtime hotplug causes the dock station MMIO window to be exhausted and acpiphp fails to allocate resources for the majority of devices on the dock station as a result. To prevent that from happening, modify acpiphp to follow the boot time resources allocation behavior so that the BIOS' resource assignments are respected during runtime hotplug too. [rjw: Changelog] References: https://bugzilla.kernel.org/show_bug.cgi?id=56531 Reported-and-tested-by: Alexander E. Patrakov Tested-by: Illya Klymov Signed-off-by: Jiang Liu Acked-by: Yinghai Lu Cc: 3.9+ Signed-off-by: Rafael J. Wysocki --- drivers/pci/hotplug/acpiphp_glue.c | 7 +++++-- drivers/pci/pci.h | 5 +++++ drivers/pci/setup-bus.c | 8 ++++---- 3 files changed, 14 insertions(+), 6 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index 716aa93fff7..050b6f9abfd 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -670,6 +670,7 @@ static int __ref enable_device(struct acpiphp_slot *slot) struct pci_bus *bus = slot->bridge->pci_bus; struct acpiphp_func *func; int num, max, pass; + LIST_HEAD(add_list); if (slot->flags & SLOT_ENABLED) goto err_exit; @@ -694,13 +695,15 @@ static int __ref enable_device(struct acpiphp_slot *slot) max = pci_scan_bridge(bus, dev, max, pass); if (pass && dev->subordinate) { check_hotplug_bridge(slot, dev); - pci_bus_size_bridges(dev->subordinate); + pcibios_resource_survey_bus(dev->subordinate); + __pci_bus_size_bridges(dev->subordinate, + &add_list); } } } } - pci_bus_assign_resources(bus); + __pci_bus_assign_resources(bus, &add_list, NULL); acpiphp_sanitize_bus(bus); acpiphp_set_hpp_values(bus); acpiphp_set_acpi_region(slot); diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 68678ed76b0..d1182c4a754 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -202,6 +202,11 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type, struct resource *res, unsigned int reg); int pci_resource_bar(struct pci_dev *dev, int resno, enum pci_bar_type *type); void pci_configure_ari(struct pci_dev *dev); +void __ref __pci_bus_size_bridges(struct pci_bus *bus, + struct list_head *realloc_head); +void __ref __pci_bus_assign_resources(const struct pci_bus *bus, + struct list_head *realloc_head, + struct list_head *fail_head); /** * pci_ari_enabled - query ARI forwarding status diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 16abaaa1f83..d254e237953 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -1044,7 +1044,7 @@ handle_done: ; } -static void __ref __pci_bus_size_bridges(struct pci_bus *bus, +void __ref __pci_bus_size_bridges(struct pci_bus *bus, struct list_head *realloc_head) { struct pci_dev *dev; @@ -1115,9 +1115,9 @@ void __ref pci_bus_size_bridges(struct pci_bus *bus) } EXPORT_SYMBOL(pci_bus_size_bridges); -static void __ref __pci_bus_assign_resources(const struct pci_bus *bus, - struct list_head *realloc_head, - struct list_head *fail_head) +void __ref __pci_bus_assign_resources(const struct pci_bus *bus, + struct list_head *realloc_head, + struct list_head *fail_head) { struct pci_bus *b; struct pci_dev *dev; -- cgit v1.2.3 From 21a31013f774c726bd199526cd673acc6432b21d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 24 Jun 2013 11:22:53 +0200 Subject: ACPI / dock / PCI: Synchronous handling of dock events for PCI devices The interactions between the ACPI dock driver and the ACPI-based PCI hotplug (acpiphp) are currently problematic because of ordering issues during hot-remove operations. First of all, the current ACPI glue code expects that physical devices will always be deleted before deleting the companion ACPI device objects. Otherwise, acpi_unbind_one() will fail with a warning message printed to the kernel log, for example: [ 185.026073] usb usb5: Oops, 'acpi_handle' corrupt [ 185.035150] pci 0000:1b:00.0: Oops, 'acpi_handle' corrupt [ 185.035515] pci 0000:18:02.0: Oops, 'acpi_handle' corrupt [ 180.013656] port1: Oops, 'acpi_handle' corrupt This means, in particular, that struct pci_dev objects have to be deleted before the struct acpi_device objects they are "glued" with. Now, the following happens the during the undocking of an ACPI-based dock station: 1) hotplug_dock_devices() invokes registered hotplug callbacks to destroy physical devices associated with the ACPI device objects depending on the dock station. It calls dd->ops->handler() for each of those device objects. 2) For PCI devices dd->ops->handler() points to handle_hotplug_event_func() that queues up a separate work item to execute _handle_hotplug_event_func() for the given device and returns immediately. That work item will be executed later. 3) hotplug_dock_devices() calls dock_remove_acpi_device() for each device depending on the dock station. This runs acpi_bus_trim() for each of them, which causes the underlying ACPI device object to be destroyed, but the work items queued up by handle_hotplug_event_func() haven't been started yet. 4) _handle_hotplug_event_func() queued up in step 2) are executed and cause the above failure to happen, because the PCI devices they handle do not have the companion ACPI device objects any more (those objects have been deleted in step 3). The possible breakage doesn't end here, though, because hotplug_dock_devices() may return before at least some of the _handle_hotplug_event_func() work items spawned by it have a chance to complete and then undock() will cause _DCK to be evaluated and that will cause the devices handled by the _handle_hotplug_event_func() to go away possibly while they are being accessed. This means that dd->ops->handler() for PCI devices should not point to handle_hotplug_event_func(). Instead, it should point to a function that will do the work of _handle_hotplug_event_func() synchronously. For this reason, introduce such a function, hotplug_event_func(), and modity acpiphp_dock_ops to point to it as the handler. Unfortunately, however, this is not sufficient, because if the dock code were not changed further, hotplug_event_func() would now deadlock with hotplug_dock_devices() that called it, since it would run unregister_hotplug_dock_device() which in turn would attempt to acquire the dock station's hp_lock mutex already acquired by hotplug_dock_devices(). To resolve that deadlock use the observation that unregister_hotplug_dock_device() won't need to acquire hp_lock if PCI bridges the devices on the dock station depend on are prevented from being removed prematurely while the first loop in hotplug_dock_devices() is in progress. To make that possible, introduce a mechanism by which the callers of register_hotplug_dock_device() can provide "init" and "release" routines that will be executed, respectively, during the addition and removal of the physical device object associated with the given ACPI device handle. Make acpiphp use two new functions, acpiphp_dock_init() and acpiphp_dock_release(), that call get_bridge() and put_bridge(), respectively, on the acpiphp bridge holding the given device, for this purpose. In addition to that, remove the dock station's list of "hotplug devices" and make the dock code always walk the whole list of "dependent devices" instead in such a way that the loops in hotplug_dock_devices() and dock_event() (replacing the loops over "hotplug devices") will take references to the list entries that register_hotplug_dock_device() has been called for. That prevents the "release" routines associated with those entries from being called while the given entry is being processed and for PCI devices this means that their bridges won't be removed (by a concurrent thread) while hotplug_event_func() handling them is being executed. This change is based on two earlier patches from Jiang Liu. References: https://bugzilla.kernel.org/show_bug.cgi?id=59501 Reported-and-tested-by: Alexander E. Patrakov Tracked-down-by: Jiang Liu Tested-by: Illya Klymov Signed-off-by: Rafael J. Wysocki Acked-by: Yinghai Lu Cc: 3.9+ --- drivers/acpi/dock.c | 137 +++++++++++++++++++++++++------------ drivers/pci/hotplug/acpiphp_glue.c | 46 +++++++++---- 2 files changed, 127 insertions(+), 56 deletions(-) (limited to 'drivers') diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c index c3b34f94382..14de9f46972 100644 --- a/drivers/acpi/dock.c +++ b/drivers/acpi/dock.c @@ -66,20 +66,21 @@ struct dock_station { spinlock_t dd_lock; struct mutex hp_lock; struct list_head dependent_devices; - struct list_head hotplug_devices; struct list_head sibling; struct platform_device *dock_device; }; static LIST_HEAD(dock_stations); static int dock_station_count; +static DEFINE_MUTEX(hotplug_lock); struct dock_dependent_device { struct list_head list; - struct list_head hotplug_list; acpi_handle handle; - const struct acpi_dock_ops *ops; - void *context; + const struct acpi_dock_ops *hp_ops; + void *hp_context; + unsigned int hp_refcount; + void (*hp_release)(void *); }; #define DOCK_DOCKING 0x00000001 @@ -111,7 +112,6 @@ add_dock_dependent_device(struct dock_station *ds, acpi_handle handle) dd->handle = handle; INIT_LIST_HEAD(&dd->list); - INIT_LIST_HEAD(&dd->hotplug_list); spin_lock(&ds->dd_lock); list_add_tail(&dd->list, &ds->dependent_devices); @@ -121,35 +121,90 @@ add_dock_dependent_device(struct dock_station *ds, acpi_handle handle) } /** - * dock_add_hotplug_device - associate a hotplug handler with the dock station - * @ds: The dock station - * @dd: The dependent device struct - * - * Add the dependent device to the dock's hotplug device list + * dock_init_hotplug - Initialize a hotplug device on a docking station. + * @dd: Dock-dependent device. + * @ops: Dock operations to attach to the dependent device. + * @context: Data to pass to the @ops callbacks and @release. + * @init: Optional initialization routine to run after setting up context. + * @release: Optional release routine to run on removal. */ -static void -dock_add_hotplug_device(struct dock_station *ds, - struct dock_dependent_device *dd) +static int dock_init_hotplug(struct dock_dependent_device *dd, + const struct acpi_dock_ops *ops, void *context, + void (*init)(void *), void (*release)(void *)) { - mutex_lock(&ds->hp_lock); - list_add_tail(&dd->hotplug_list, &ds->hotplug_devices); - mutex_unlock(&ds->hp_lock); + int ret = 0; + + mutex_lock(&hotplug_lock); + + if (dd->hp_context) { + ret = -EEXIST; + } else { + dd->hp_refcount = 1; + dd->hp_ops = ops; + dd->hp_context = context; + dd->hp_release = release; + } + + if (!WARN_ON(ret) && init) + init(context); + + mutex_unlock(&hotplug_lock); + return ret; } /** - * dock_del_hotplug_device - remove a hotplug handler from the dock station - * @ds: The dock station - * @dd: the dependent device struct + * dock_release_hotplug - Decrement hotplug reference counter of dock device. + * @dd: Dock-dependent device. * - * Delete the dependent device from the dock's hotplug device list + * Decrement the reference counter of @dd and if 0, detach its hotplug + * operations from it, reset its context pointer and run the optional release + * routine if present. */ -static void -dock_del_hotplug_device(struct dock_station *ds, - struct dock_dependent_device *dd) +static void dock_release_hotplug(struct dock_dependent_device *dd) { - mutex_lock(&ds->hp_lock); - list_del(&dd->hotplug_list); - mutex_unlock(&ds->hp_lock); + void (*release)(void *) = NULL; + void *context = NULL; + + mutex_lock(&hotplug_lock); + + if (dd->hp_context && !--dd->hp_refcount) { + dd->hp_ops = NULL; + context = dd->hp_context; + dd->hp_context = NULL; + release = dd->hp_release; + dd->hp_release = NULL; + } + + if (release && context) + release(context); + + mutex_unlock(&hotplug_lock); +} + +static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event, + bool uevent) +{ + acpi_notify_handler cb = NULL; + bool run = false; + + mutex_lock(&hotplug_lock); + + if (dd->hp_context) { + run = true; + dd->hp_refcount++; + if (dd->hp_ops) + cb = uevent ? dd->hp_ops->uevent : dd->hp_ops->handler; + } + + mutex_unlock(&hotplug_lock); + + if (!run) + return; + + if (cb) + cb(dd->handle, event, dd->hp_context); + + dock_release_hotplug(dd); } /** @@ -360,9 +415,8 @@ static void hotplug_dock_devices(struct dock_station *ds, u32 event) /* * First call driver specific hotplug functions */ - list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list) - if (dd->ops && dd->ops->handler) - dd->ops->handler(dd->handle, event, dd->context); + list_for_each_entry(dd, &ds->dependent_devices, list) + dock_hotplug_event(dd, event, false); /* * Now make sure that an acpi_device is created for each @@ -398,9 +452,8 @@ static void dock_event(struct dock_station *ds, u32 event, int num) if (num == DOCK_EVENT) kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); - list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list) - if (dd->ops && dd->ops->uevent) - dd->ops->uevent(dd->handle, event, dd->context); + list_for_each_entry(dd, &ds->dependent_devices, list) + dock_hotplug_event(dd, event, true); if (num != DOCK_EVENT) kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); @@ -570,19 +623,24 @@ EXPORT_SYMBOL_GPL(unregister_dock_notifier); * @handle: the handle of the device * @ops: handlers to call after docking * @context: device specific data + * @init: Optional initialization routine to run after registration + * @release: Optional release routine to run on unregistration * * If a driver would like to perform a hotplug operation after a dock * event, they can register an acpi_notifiy_handler to be called by * the dock driver after _DCK is executed. */ -int -register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops, - void *context) +int register_hotplug_dock_device(acpi_handle handle, + const struct acpi_dock_ops *ops, void *context, + void (*init)(void *), void (*release)(void *)) { struct dock_dependent_device *dd; struct dock_station *dock_station; int ret = -EINVAL; + if (WARN_ON(!context)) + return -EINVAL; + if (!dock_station_count) return -ENODEV; @@ -597,12 +655,8 @@ register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops * ops */ dd = find_dock_dependent_device(dock_station, handle); - if (dd) { - dd->ops = ops; - dd->context = context; - dock_add_hotplug_device(dock_station, dd); + if (dd && !dock_init_hotplug(dd, ops, context, init, release)) ret = 0; - } } return ret; @@ -624,7 +678,7 @@ void unregister_hotplug_dock_device(acpi_handle handle) list_for_each_entry(dock_station, &dock_stations, sibling) { dd = find_dock_dependent_device(dock_station, handle); if (dd) - dock_del_hotplug_device(dock_station, dd); + dock_release_hotplug(dd); } } EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device); @@ -953,7 +1007,6 @@ static int __init dock_add(acpi_handle handle) mutex_init(&dock_station->hp_lock); spin_lock_init(&dock_station->dd_lock); INIT_LIST_HEAD(&dock_station->sibling); - INIT_LIST_HEAD(&dock_station->hotplug_devices); ATOMIC_INIT_NOTIFIER_HEAD(&dock_notifier_list); INIT_LIST_HEAD(&dock_station->dependent_devices); diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index 050b6f9abfd..59df8575a48 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -61,6 +61,7 @@ static DEFINE_MUTEX(bridge_mutex); static void handle_hotplug_event_bridge (acpi_handle, u32, void *); static void acpiphp_sanitize_bus(struct pci_bus *bus); static void acpiphp_set_hpp_values(struct pci_bus *bus); +static void hotplug_event_func(acpi_handle handle, u32 type, void *context); static void handle_hotplug_event_func(acpi_handle handle, u32 type, void *context); static void free_bridge(struct kref *kref); @@ -147,7 +148,7 @@ static int post_dock_fixups(struct notifier_block *nb, unsigned long val, static const struct acpi_dock_ops acpiphp_dock_ops = { - .handler = handle_hotplug_event_func, + .handler = hotplug_event_func, }; /* Check whether the PCI device is managed by native PCIe hotplug driver */ @@ -179,6 +180,20 @@ static bool device_is_managed_by_native_pciehp(struct pci_dev *pdev) return true; } +static void acpiphp_dock_init(void *data) +{ + struct acpiphp_func *func = data; + + get_bridge(func->slot->bridge); +} + +static void acpiphp_dock_release(void *data) +{ + struct acpiphp_func *func = data; + + put_bridge(func->slot->bridge); +} + /* callback routine to register each ACPI PCI slot object */ static acpi_status register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) @@ -298,7 +313,8 @@ register_slot(acpi_handle handle, u32 lvl, void *context, void **rv) */ newfunc->flags &= ~FUNC_HAS_EJ0; if (register_hotplug_dock_device(handle, - &acpiphp_dock_ops, newfunc)) + &acpiphp_dock_ops, newfunc, + acpiphp_dock_init, acpiphp_dock_release)) dbg("failed to register dock device\n"); /* we need to be notified when dock events happen @@ -1068,22 +1084,12 @@ static void handle_hotplug_event_bridge(acpi_handle handle, u32 type, alloc_acpi_hp_work(handle, type, context, _handle_hotplug_event_bridge); } -static void _handle_hotplug_event_func(struct work_struct *work) +static void hotplug_event_func(acpi_handle handle, u32 type, void *context) { - struct acpiphp_func *func; + struct acpiphp_func *func = context; char objname[64]; struct acpi_buffer buffer = { .length = sizeof(objname), .pointer = objname }; - struct acpi_hp_work *hp_work; - acpi_handle handle; - u32 type; - - hp_work = container_of(work, struct acpi_hp_work, work); - handle = hp_work->handle; - type = hp_work->type; - func = (struct acpiphp_func *)hp_work->context; - - acpi_scan_lock_acquire(); acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer); @@ -1116,6 +1122,18 @@ static void _handle_hotplug_event_func(struct work_struct *work) warn("notify_handler: unknown event type 0x%x for %s\n", type, objname); break; } +} + +static void _handle_hotplug_event_func(struct work_struct *work) +{ + struct acpi_hp_work *hp_work; + struct acpiphp_func *func; + + hp_work = container_of(work, struct acpi_hp_work, work); + func = hp_work->context; + acpi_scan_lock_acquire(); + + hotplug_event_func(hp_work->handle, hp_work->type, func); acpi_scan_lock_release(); kfree(hp_work); /* allocated in handle_hotplug_event_func */ -- cgit v1.2.3 From 44521527be36172864e6e7a6fba4b66e9aa48e40 Mon Sep 17 00:00:00 2001 From: Aaron Lu Date: Thu, 20 Jun 2013 09:38:34 +0800 Subject: libata-acpi: add back ACPI based hotplug functionality Commit 30dcf76acc69 "libata: migrate ACPI code over to new bindings" mistakenly dropped the code to register hotplug notificaion handler for ATA port/devices, causing regression for people using ATA bay, as kernel bug #59871 shows. Fix this by adding back the hotplug notification handler registration code. Since this code has to be run once and notification needs to be installed on every ATA port/devices handle no matter if there is actual device attached, we can't do this in binding time for ATA device ACPI handle, as the binding only occurs when a SCSI device is created, i.e. there is device attached. So introduce the ata_acpi_hotplug_init() function to loop scan all ATA ACPI handles and if it is available, install the notificaion handler for it during ATA init time. With the ATA ACPI handle binding to SCSI device tree, it is possible now that when the SCSI hotplug work removes the SCSI device, the ACPI unbind function will find that the corresponding ACPI device has already been deleted by dock driver, causing a scaring message like: [ 128.263966] scsi 4:0:0:0: Oops, 'acpi_handle' corrupt Fix this by waiting for SCSI hotplug task finish in our notificaion handler, so that the removal of ACPI device done in ACPI unbind function triggered by the removal of SCSI device is run earlier when ACPI device is still available. [rjw: Rebased] References: https://bugzilla.kernel.org/show_bug.cgi?id=59871 Reported-bisected-and-tested-by: Dirk Griesbach Signed-off-by: Aaron Lu Acked-by: Tejun Heo Cc: 3.6+ Signed-off-by: Rafael J. Wysocki --- drivers/ata/libata-acpi.c | 37 ++++++++++++++++++++++++++++++++++++- drivers/ata/libata-core.c | 2 ++ drivers/ata/libata.h | 2 ++ 3 files changed, 40 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/ata/libata-acpi.c b/drivers/ata/libata-acpi.c index 87f2f395d79..cf4e7020ada 100644 --- a/drivers/ata/libata-acpi.c +++ b/drivers/ata/libata-acpi.c @@ -156,8 +156,10 @@ static void ata_acpi_handle_hotplug(struct ata_port *ap, struct ata_device *dev, spin_unlock_irqrestore(ap->lock, flags); - if (wait) + if (wait) { ata_port_wait_eh(ap); + flush_work(&ap->hotplug_task.work); + } } static void ata_acpi_dev_notify_dock(acpi_handle handle, u32 event, void *data) @@ -214,6 +216,39 @@ static const struct acpi_dock_ops ata_acpi_ap_dock_ops = { .uevent = ata_acpi_ap_uevent, }; +void ata_acpi_hotplug_init(struct ata_host *host) +{ + int i; + + for (i = 0; i < host->n_ports; i++) { + struct ata_port *ap = host->ports[i]; + acpi_handle handle; + struct ata_device *dev; + + if (!ap) + continue; + + handle = ata_ap_acpi_handle(ap); + if (handle) { + /* we might be on a docking station */ + register_hotplug_dock_device(handle, + &ata_acpi_ap_dock_ops, ap, + NULL, NULL); + } + + ata_for_each_dev(dev, &ap->link, ALL) { + handle = ata_dev_acpi_handle(dev); + if (!handle) + continue; + + /* we might be on a docking station */ + register_hotplug_dock_device(handle, + &ata_acpi_dev_dock_ops, + dev, NULL, NULL); + } + } +} + /** * ata_acpi_dissociate - dissociate ATA host from ACPI objects * @host: target ATA host diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index f2184276539..adf002a3c58 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6148,6 +6148,8 @@ int ata_host_register(struct ata_host *host, struct scsi_host_template *sht) if (rc) goto err_tadd; + ata_acpi_hotplug_init(host); + /* set cable, sata_spd_limit and report */ for (i = 0; i < host->n_ports; i++) { struct ata_port *ap = host->ports[i]; diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h index c949dd311b2..577d902bc4d 100644 --- a/drivers/ata/libata.h +++ b/drivers/ata/libata.h @@ -122,6 +122,7 @@ extern int ata_acpi_register(void); extern void ata_acpi_unregister(void); extern void ata_acpi_bind(struct ata_device *dev); extern void ata_acpi_unbind(struct ata_device *dev); +extern void ata_acpi_hotplug_init(struct ata_host *host); #else static inline void ata_acpi_dissociate(struct ata_host *host) { } static inline int ata_acpi_on_suspend(struct ata_port *ap) { return 0; } @@ -134,6 +135,7 @@ static inline int ata_acpi_register(void) { return 0; } static inline void ata_acpi_unregister(void) { } static inline void ata_acpi_bind(struct ata_device *dev) { } static inline void ata_acpi_unbind(struct ata_device *dev) { } +static inline void ata_acpi_hotplug_init(struct ata_host *host) {} #endif /* libata-scsi.c */ -- cgit v1.2.3 From c28375583b6471c1cb833a628ab6afb5b69079d0 Mon Sep 17 00:00:00 2001 From: Jacob Shin Date: Tue, 25 Jun 2013 22:42:37 +0200 Subject: cpufreq: fix NULL pointer deference at od_set_powersave_bias() When initializing the default powersave_bias value, we need to first make sure that this policy is running the ondemand governor. Reported-and-tested-by: Tim Gardner Signed-off-by: Jacob Shin Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/cpufreq_ondemand.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c index 4b9bb5def6f..93eb5cbcc1f 100644 --- a/drivers/cpufreq/cpufreq_ondemand.c +++ b/drivers/cpufreq/cpufreq_ondemand.c @@ -47,6 +47,8 @@ static struct od_ops od_ops; static struct cpufreq_governor cpufreq_gov_ondemand; #endif +static unsigned int default_powersave_bias; + static void ondemand_powersave_bias_init_cpu(int cpu) { struct od_cpu_dbs_info_s *dbs_info = &per_cpu(od_cpu_dbs_info, cpu); @@ -543,7 +545,7 @@ static int od_init(struct dbs_data *dbs_data) tuners->sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR; tuners->ignore_nice = 0; - tuners->powersave_bias = 0; + tuners->powersave_bias = default_powersave_bias; tuners->io_is_busy = should_io_be_busy(); dbs_data->tuners = tuners; @@ -585,6 +587,7 @@ static void od_set_powersave_bias(unsigned int powersave_bias) unsigned int cpu; cpumask_t done; + default_powersave_bias = powersave_bias; cpumask_clear(&done); get_online_cpus(); @@ -593,11 +596,17 @@ static void od_set_powersave_bias(unsigned int powersave_bias) continue; policy = per_cpu(od_cpu_dbs_info, cpu).cdbs.cur_policy; - dbs_data = policy->governor_data; - od_tuners = dbs_data->tuners; - od_tuners->powersave_bias = powersave_bias; + if (!policy) + continue; cpumask_or(&done, &done, policy->cpus); + + if (policy->governor != &cpufreq_gov_ondemand) + continue; + + dbs_data = policy->governor_data; + od_tuners = dbs_data->tuners; + od_tuners->powersave_bias = default_powersave_bias; } put_online_cpus(); } -- cgit v1.2.3