linux/drivers/acpi, branch v3.12

ACPI / PM: Drop two functions that are not used any more

2013-10-17T13:44:48Z

Two functions defined in device_pm.c, acpi_dev_pm_add_dependent() and acpi_dev_pm_remove_dependent(), have no callers and may be dropped, so drop them. Moreover, they are the only functions adding entries to and removing entries from the power_dependent list in struct acpi_device, so drop that list too. Signed-off-by: Rafael J. Wysocki

ACPI / power: Drop automaitc resume of power resource dependent devices

2013-10-16T21:05:42Z

The mechanism causing devices depending on a given power resource (that is, devices that can be in D0 only if that power resource is on) to be resumed automatically when the power resource is turned on (and their "inferred" power state becomes D0 as a result) is inherently racy and in fact unnecessary. It is racy, because if the power resource is turned on and then immediately off, the device resume triggered by the first transition to "on" may still happen, causing the power resource to be turned on again. That again will trigger the "resume of dependent devices" mechanism, but if the devices in question are not in use, they will be suspended in the meantime causing the power resource to be turned off. However, the "resume of dependent devices" will next resume them again and so on. In some cases (USB port PM in particular) that leads to an endless busy loop of flipping the resource on and off continuously. It is needless, because whoever turns a power resource on will most likely turn it off at some point and the devices that go into "D0" as a result of turning it on will then go back into D3cold (generally, the state they were in before). Moreover, turning on all power resources a device needs to go into D0 is not sufficient for a full transition into D0 in general. Namely, _PS0 may need to be executed in addition to that in some cases. This means that the whole rationale of the "resume of dependent devices" mechanism was incorrect to begin with and it's best to remove it entirely. Signed-off-by: Rafael J. Wysocki

ACPI: remove /proc/acpi/event from ACPI_BUTTON help

2013-10-15T22:31:47Z

Commit 1696d9d (ACPI: Remove the old /proc/acpi/event interface) left /proc/acpi/event in the ACPI_BUTTON help in Kconfig, so remove it from there. [rjw: Changelog] Signed-off-by: Krzysztof Mazur Signed-off-by: Rafael J. Wysocki

ACPI / power: Release resource_lock after acpi_power_get_state() return error

2013-10-15T22:26:42Z

In acpi_resume_power_resources() resource_lock should be released when acpi_power_get_state() fails and before passing to next power resource on the list. Signed-off-by: Lan Tianyu Signed-off-by: Rafael J. Wysocki

ACPI / PM / Documentation: Replace outdated project links and addresses

2013-10-11T11:22:43Z

Some links to projects web pages and e-mail addresses in ACPI/PM documentation and Kconfig are outdated, so update them. Signed-off-by: Rafael J. Wysocki

ACPI: Use EXPORT_SYMBOL() for acpi_bus_get_device()

2013-10-01T21:02:43Z

Commit caf5c03f (ACPI: Move acpi_bus_get_device() from bus.c to scan.c) caused acpi_bus_get_device() to be exported using EXPORT_SYMBOL_GPL(), but that broke some binary drivers in existence, so revert that change. Reported-by: Peter Hurley Signed-off-by: Rafael J. Wysocki

ACPI / scan: fix typo in comments of acpi_bus_unregister_driver()

2013-09-25T17:46:48Z

"APIC" should be "ACPI" here. Signed-off-by: Hanjun Guo Signed-off-by: Rafael J. Wysocki

ACPI / IPMI: Fix atomic context requirement of ipmi_msg_handler()

2013-09-25T01:12:05Z

This patch fixes the issues indicated by the test results that ipmi_msg_handler() is invoked in atomic context. BUG: scheduling while atomic: kipmi0/18933/0x10000100 Modules linked in: ipmi_si acpi_ipmi ... CPU: 3 PID: 18933 Comm: kipmi0 Tainted: G AW 3.10.0-rc7+ #2 Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.0027.070120100606 07/01/2010 ffff8838245eea00 ffff88103fc63c98 ffffffff814c4a1e ffff88103fc63ca8 ffffffff814bfbab ffff88103fc63d28 ffffffff814c73e0 ffff88103933cbd4 0000000000000096 ffff88103fc63ce8 ffff88102f618000 ffff881035c01fd8 Call Trace: [] dump_stack+0x19/0x1b [] __schedule_bug+0x46/0x54 [] __schedule+0x83/0x59c [] __cond_resched+0x22/0x2d [] _cond_resched+0x14/0x1d [] mutex_lock+0x11/0x32 [] ? __default_send_IPI_dest_field.constprop.0+0x53/0x58 [] ipmi_msg_handler+0x23/0x166 [ipmi_si] [] deliver_response+0x55/0x5a [] handle_new_recv_msgs+0xb67/0xc65 [] ? read_tsc+0x9/0x19 [] ? _raw_spin_lock_irq+0xa/0xc [] ipmi_thread+0x5c/0x146 [ipmi_si] ... Also Tony Camuso says: We were getting occasional "Scheduling while atomic" call traces during boot on some systems. Problem was first seen on a Cisco C210 but we were able to reproduce it on a Cisco c220m3. Setting CONFIG_LOCKDEP and LOCKDEP_SUPPORT to 'y' exposed a lockdep around tx_msg_lock in acpi_ipmi.c struct acpi_ipmi_device. ================================= [ INFO: inconsistent lock state ] 2.6.32-415.el6.x86_64-debug-splck #1 --------------------------------- inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage. ksoftirqd/3/17 [HC0[0]:SC1[1]:HE1:SE0] takes: (&ipmi_device->tx_msg_lock){+.?...}, at: [] ipmi_msg_handler+0x71/0x126 {SOFTIRQ-ON-W} state was registered at: [] __lock_acquire+0x63c/0x1570 [] lock_acquire+0xa4/0x120 [] __mutex_lock_common+0x4c/0x400 [] mutex_lock_nested+0x4a/0x60 [] acpi_ipmi_space_handler+0x11b/0x234 [] acpi_ev_address_space_dispatch+0x170/0x1be The fix implemented by this change has been tested by Tony: Tested the patch in a boot loop with lockdep debug enabled and never saw the problem in over 400 reboots. Reported-and-tested-by: Tony Camuso Signed-off-by: Lv Zheng Reviewed-by: Huang Ying Signed-off-by: Rafael J. Wysocki

Merge tag 'pm+acpi-fixes-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

2013-09-12T18:22:45Z

Pull ACPI and power management fixes from Rafael Wysocki: "All of these commits are fixes that have emerged recently and some of them fix bugs introduced during this merge window. Specifics: 1) ACPI-based PCI hotplug (ACPIPHP) fixes related to spurious events After the recent ACPIPHP changes we've seen some interesting breakage on a system that triggers device check notifications during boot for non-existing devices. Although those notifications are really spurious, we should be able to deal with them nevertheless and that shouldn't introduce too much overhead. Four commits to make that work properly. 2) Memory hotplug and hibernation mutual exclusion rework This was maent to be a cleanup, but it happens to fix a classical ABBA deadlock between system suspend/hibernation and ACPI memory hotplug which is possible if they are started roughly at the same time. Three commits rework memory hotplug so that it doesn't acquire pm_mutex and make hibernation use device_hotplug_lock which prevents it from racing with memory hotplug. 3) ACPI Intel LPSS (Low-Power Subsystem) driver crash fix The ACPI LPSS driver crashes during boot on Apple Macbook Air with Haswell that has slightly unusual BIOS configuration in which one of the LPSS device's _CRS method doesn't return all of the information expected by the driver. Fix from Mika Westerberg, for stable. 4) ACPICA fix related to Store->ArgX operation AML interpreter fix for obscure breakage that causes AML to be executed incorrectly on some machines (observed in practice). From Bob Moore. 5) ACPI core fix for PCI ACPI device objects lookup There still are cases in which there is more than one ACPI device object matching a given PCI device and we don't choose the one that the BIOS expects us to choose, so this makes the lookup take more criteria into account in those cases. 6) Fix to prevent cpuidle from crashing in some rare cases If the result of cpuidle_get_driver() is NULL, which can happen on some systems, cpuidle_driver_ref() will crash trying to use that pointer and the Daniel Fu's fix prevents that from happening. 7) cpufreq fixes related to CPU hotplug Stephen Boyd reported a number of concurrency problems with cpufreq related to CPU hotplug which are addressed by a series of fixes from Srivatsa S Bhat and Viresh Kumar. 8) cpufreq fix for time conversion in time_in_state attribute Time conversion carried out by cpufreq when user space attempts to read /sys/devices/system/cpu/cpu*/cpufreq/stats/time_in_state won't work correcty if cputime_t doesn't map directly to jiffies. Fix from Andreas Schwab. 9) Revert of a troublesome cpufreq commit Commit 7c30ed5 (cpufreq: make sure frequency transitions are serialized) was intended to address some known concurrency problems in cpufreq related to the ordering of transitions, but unfortunately it introduced several problems of its own, so I decided to revert it now and address the original problems later in a more robust way. 10) Intel Haswell CPU models for intel_pstate from Nell Hardcastle. 11) cpufreq fixes related to system suspend/resume The recent cpufreq changes that made it preserve CPU sysfs attributes over suspend/resume cycles introduced a possible NULL pointer dereference that caused it to crash during the second attempt to suspend. Three commits from Srivatsa S Bhat fix that problem and a couple of related issues. 12) cpufreq locking fix cpufreq_policy_restore() should acquire the lock for reading, but it acquires it for writing. Fix from Lan Tianyu" * tag 'pm+acpi-fixes-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (25 commits) cpufreq: Acquire the lock in cpufreq_policy_restore() for reading cpufreq: Prevent problems in update_policy_cpu() if last_cpu == new_cpu cpufreq: Restructure if/else block to avoid unintended behavior cpufreq: Fix crash in cpufreq-stats during suspend/resume intel_pstate: Add Haswell CPU models Revert "cpufreq: make sure frequency transitions are serialized" cpufreq: Use signed type for 'ret' variable, to store negative error values cpufreq: Remove temporary fix for race between CPU hotplug and sysfs-writes cpufreq: Synchronize the cpufreq store_*() routines with CPU hotplug cpufreq: Invoke __cpufreq_remove_dev_finish() after releasing cpu_hotplug.lock cpufreq: Split __cpufreq_remove_dev() into two parts cpufreq: Fix wrong time unit conversion cpufreq: serialize calls to __cpufreq_governor() cpufreq: don't allow governor limits to be changed when it is disabled ACPI / bind: Prefer device objects with _STA to those without it ACPI / hotplug / PCI: Avoid parent bus rescans on spurious device checks ACPI / hotplug / PCI: Use _OST to notify firmware about notify status ACPI / hotplug / PCI: Avoid doing too much for spurious notifies ACPICA: Fix for a Store->ArgX when ArgX contains a reference to a field. ACPI / hotplug / PCI: Don't trim devices before scanning the namespace ...

Merge branch 'acpi-bind'

2013-09-11T13:22:27Z

* acpi-bind: ACPI / bind: Prefer device objects with _STA to those without it