From d2f6650a950dadd20667a04a9dc785f240d43695 Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Fri, 29 Jan 2010 17:48:51 +0100 Subject: ACPI: Add NULL pointer check in acpi_bus_start If acpi_bus_add does not return a device and it's passed to acpi_bus_start, bad things will happen: BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 IP: [] acpi_bus_start+0x14/0x24 ... [] acpiphp_bus_add+0xba/0x130 [acpiphp] [] enable_device+0x132/0x2ff [acpiphp] [] acpiphp_enable_slot+0xb8/0x130 [acpiphp] [] handle_hotplug_event_func+0x87/0x190 [acpiphp] Next patch would make this NULL pointer check obsolete, but better having one more than one missing... Signed-off-by: Thomas Renninger Acked-by: Bjorn Helgaas CC: stable@kernel.org Signed-off-by: Len Brown --- drivers/acpi/scan.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index ff9f6226085d..8044583f3034 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1357,6 +1357,9 @@ int acpi_bus_start(struct acpi_device *device) { struct acpi_bus_ops ops; + if (!device) + return -EINVAL; + memset(&ops, 0, sizeof(ops)); ops.acpi_op_start = 1; -- cgit v1.2.3 From 7779688fc3d1ceddad84846a7b0affbe8e78ec6e Mon Sep 17 00:00:00 2001 From: Thomas Renninger Date: Fri, 29 Jan 2010 17:48:52 +0100 Subject: ACPI: acpi_bus_{scan,bus,add}: return -ENODEV if no device was found Callers (acpi_memhotplug.c, dock.c and others) check for the return value of acpi_bus_add() and assume a valid device was returned in case zero was returned. Thus return -ENODEV if no device was found in acpi_bus_scan and propagate this through acpi_bus_add and acpi_bus_start. Also remove a confusing comment in acpiphp_glue.c, acpi_bus_scan will and cannot invoke if acpi_bus_add returns no valid device. Signed-off-by: Thomas Renninger Acked-by: Bjorn Helgaas Signed-off-by: Len Brown --- drivers/acpi/scan.c | 24 +++++++++++++++++++----- 1 file changed, 19 insertions(+), 5 deletions(-) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 8044583f3034..3e009674f333 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1336,9 +1336,25 @@ static int acpi_bus_scan(acpi_handle handle, struct acpi_bus_ops *ops, if (child) *child = device; - return 0; + + if (device) + return 0; + else + return -ENODEV; } +/* + * acpi_bus_add and acpi_bus_start + * + * scan a given ACPI tree and (probably recently hot-plugged) + * create and add or starts found devices. + * + * If no devices were found -ENODEV is returned which does not + * mean that this is a real error, there just have been no suitable + * ACPI objects in the table trunk from which the kernel could create + * a device and add/start an appropriate driver. + */ + int acpi_bus_add(struct acpi_device **child, struct acpi_device *parent, acpi_handle handle, int type) @@ -1348,8 +1364,7 @@ acpi_bus_add(struct acpi_device **child, memset(&ops, 0, sizeof(ops)); ops.acpi_op_add = 1; - acpi_bus_scan(handle, &ops, child); - return 0; + return acpi_bus_scan(handle, &ops, child); } EXPORT_SYMBOL(acpi_bus_add); @@ -1363,8 +1378,7 @@ int acpi_bus_start(struct acpi_device *device) memset(&ops, 0, sizeof(ops)); ops.acpi_op_start = 1; - acpi_bus_scan(device->handle, &ops, NULL); - return 0; + return acpi_bus_scan(device->handle, &ops, NULL); } EXPORT_SYMBOL(acpi_bus_start); -- cgit v1.2.3 From f517709d65beed95f52f021b43e3035b52ef791a Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 17 Feb 2010 23:41:49 +0100 Subject: ACPI / PM: Add more run-time wake-up fields Use the run_wake flag to mark all devices for which run-time wake-up events may be generated by the platform. Introduce a new wake-up flag, always_enabled, for marking devices that should be permanently enabled to generate run-time events. Also, introduce a reference counter for run-wake devices and a function that will initialize all of the run-time wake-up fields for given device. Signed-off-by: Rafael J. Wysocki Acked-by: Len Brown Signed-off-by: Jesse Barnes --- drivers/acpi/scan.c | 37 +++++++++++++++++++++++++++---------- 1 file changed, 27 insertions(+), 10 deletions(-) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 3e009674f333..7491a52ad97a 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -741,19 +741,39 @@ acpi_bus_extract_wakeup_device_power_package(struct acpi_device *device, return AE_OK; } -static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device) +static void acpi_bus_set_run_wake_flags(struct acpi_device *device) { - acpi_status status = 0; - struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; - union acpi_object *package = NULL; - int psw_error; - struct acpi_device_id button_device_ids[] = { {"PNP0C0D", 0}, {"PNP0C0C", 0}, {"PNP0C0E", 0}, {"", 0}, }; + acpi_status status; + acpi_event_status event_status; + + device->wakeup.run_wake_count = 0; + + /* Power button, Lid switch always enable wakeup */ + if (!acpi_match_device_ids(device, button_device_ids)) { + device->wakeup.flags.run_wake = 1; + device->wakeup.flags.always_enabled = 1; + return; + } + + status = acpi_get_gpe_status(NULL, device->wakeup.gpe_number, + ACPI_NOT_ISR, &event_status); + if (status == AE_OK) + device->wakeup.flags.run_wake = + !!(event_status & ACPI_EVENT_FLAG_HANDLE); +} + +static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device) +{ + acpi_status status = 0; + struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; + union acpi_object *package = NULL; + int psw_error; /* _PRW */ status = acpi_evaluate_object(device->handle, "_PRW", NULL, &buffer); @@ -773,6 +793,7 @@ static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device) device->wakeup.flags.valid = 1; device->wakeup.prepare_count = 0; + acpi_bus_set_run_wake_flags(device); /* Call _PSW/_DSW object to disable its ability to wake the sleeping * system for the ACPI device with the _PRW object. * The _PSW object is depreciated in ACPI 3.0 and is replaced by _DSW. @@ -784,10 +805,6 @@ static int acpi_bus_get_wakeup_device_flags(struct acpi_device *device) ACPI_DEBUG_PRINT((ACPI_DB_INFO, "error in _DSW or _PSW evaluation\n")); - /* Power button, Lid switch always enable wakeup */ - if (!acpi_match_device_ids(device, button_device_ids)) - device->wakeup.flags.run_wake = 1; - end: if (ACPI_FAILURE(status)) device->flags.wake_capable = 0; -- cgit v1.2.3 From b67ea76172d4b1922c4b3c46c8ea8e9fec1ff38c Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Wed, 17 Feb 2010 23:44:09 +0100 Subject: PCI / ACPI / PM: Platform support for PCI PME wake-up Although the majority of PCI devices can generate PMEs that in principle may be used to wake up devices suspended at run time, platform support is generally necessary to convert PMEs into wake-up events that can be delivered to the kernel. If ACPI is used for this purpose, PME signals generated by a PCI device will trigger the ACPI GPE associated with the device to generate an ACPI wake-up event that we can set up a handler for, provided that everything is configured correctly. Unfortunately, the subset of PCI devices that have GPEs associated with them is quite limited. The devices without dedicated GPEs have to rely on the GPEs associated with other devices (in the majority of cases their upstream bridges and, possibly, the root bridge) to generate ACPI wake-up events in response to PME signals from them. Add ACPI platform support for PCI PME wake-up: o Add a framework making is possible to use ACPI system notify handlers for run-time PM. o Add new PCI platform callback ->run_wake() to struct pci_platform_pm_ops allowing us to enable/disable the platform to generate wake-up events for given device. Implemet this callback for the ACPI platform. o Define ACPI wake-up handlers for PCI devices and PCI root buses and make the PCI-ACPI binding code register wake-up notifiers for all PCI devices present in the ACPI tables. o Add function pci_dev_run_wake() which can be used by PCI drivers to check if given device is capable of generating wake-up events at run time. Developed in cooperation with Matthew Garrett . Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/acpi/scan.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 7491a52ad97a..fb7fc24fe727 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -753,6 +753,7 @@ static void acpi_bus_set_run_wake_flags(struct acpi_device *device) acpi_event_status event_status; device->wakeup.run_wake_count = 0; + device->wakeup.flags.notifier_present = 0; /* Power button, Lid switch always enable wakeup */ if (!acpi_match_device_ids(device, button_device_ids)) { -- cgit v1.2.3