Currently pm_pr_dbg() is used to filter kernel pm debug messages based
on pm_debug_messages_on flag. The problem is if we enable/disable this
flag it will affect all pm_pr_dbg() calls at once, so we can't
individually control them.
This patch changes pm_pr_dbg() implementation as such:
- If pm_debug_messages_on is enabled, print the message.
- If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is
enabled, only print the messages explicitly enabled on
/sys/kernel/debug/dynamic_debug/control.
- If pm_debug_messages_on is disabled and CONFIG_DYNAMIC_DEBUG is
disabled, don't print the message.
Signed-off-by: David Cohen <dacohen@pm.me>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After commit e3728b50cd ("ACPI: PM: s2idle: Avoid possible race
related to the EC GPE") wakeup interrupts occurring immediately after
the one discarded by acpi_s2idle_wake() may be missed. Moreover, if
the SCI triggers again immediately after the rearming in
acpi_s2idle_wake(), that wakeup may be missed too.
The problem is that pm_system_irq_wakeup() only calls pm_system_wakeup()
when pm_wakeup_irq is 0, but that's not the case any more after the
interrupt causing acpi_s2idle_wake() to run until pm_wakeup_irq is
cleared by the pm_wakeup_clear() call in s2idle_loop(). However,
there may be wakeup interrupts occurring in that time frame and if
that happens, they will be missed.
To address that issue first move the clearing of pm_wakeup_irq to
the point at which it is known that the interrupt causing
acpi_s2idle_wake() to tun will be discarded, before rearming the SCI
for wakeup. Moreover, because that only reduces the size of the
time window in which the issue may manifest itself, allow
pm_system_irq_wakeup() to register two second wakeup interrupts in
a row and, when discarding the first one, replace it with the second
one. [Of course, this assumes that only one wakeup interrupt can be
discarded in one go, but currently that is the case and I am not
aware of any plans to change that.]
Fixes: e3728b50cd ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
It is an unused wrapper forcing kmalloc allocation for registering
nosave regions. Also, rename __register_nosave_region() to
register_nosave_region() now that there is no need for disambiguation.
Signed-off-by: Amadeusz Sławiński <amadeuszx.slawinski@linux.intel.com>
Reviewed-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Theoretically, when the hardware signature in FACS changes, the OS
is supposed to gracefully decline to attempt to resume from S4:
"If the signature has changed, OSPM will not restore the system
context and can boot from scratch"
In practice, Windows doesn't do this and many laptop vendors do allow
the signature to change especially when docking/undocking, so it would
be a bad idea to simply comply with the specification by default in the
general case.
However, there are use cases where we do want the compliant behaviour
and we know it's safe. Specifically, when resuming virtual machines where
we know the hypervisor has changed sufficiently that resume will fail.
We really want to be able to *tell* the guest kernel not to try, so it
boots cleanly and doesn't just crash. This patch provides a way to opt
in to the spec-compliant behaviour on the command line.
A follow-up patch may do this automatically for certain "known good"
machines based on a DMI match, or perhaps just for all hypervisor
guests since there's no good reason a hypervisor would change the
hardware_signature that it exposes to guests *unless* it wants them
to obey the ACPI specification.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Abstract platform specific mechanics for nvdimm firmware activation
behind a handful of generic ops. At the bus level ->activate_state()
indicates the unified state (idle, busy, armed) of all DIMMs on the bus,
and ->capability() indicates the system state expectations for activate.
At the DIMM level ->activate_state() indicates the per-DIMM state,
->activate_result() indicates the outcome of the last activation
attempt, and ->arm() attempts to transition the DIMM from 'idle' to
'armed'.
A new hibernate_quiet_exec() facility is added to support firmware
activation in an OS defined system quiesce state. It leverages the fact
that the hibernate-freeze state wants to assert that a memory
hibernation snapshot can be taken. This is in contrast to a platform
firmware defined quiesce state that may forcefully quiet the memory
controller independent of whether an individual device-driver properly
supports hibernate-freeze.
The libnvdimm sysfs interface is extended to support detection of a
firmware activate capability. The mechanism supports enumeration and
triggering of firmware activate, optionally in the
hibernate_quiet_exec() context.
[rafael: hibernate_quiet_exec() proposal]
[vishal: fix up sparse warning, grammar in Documentation/]
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Hibernation via snapshot device requires write permission to the swap
block device, the one that more often (but not necessarily) is used to
store the hibernation image.
With this patch, such permissions are granted iff:
1) snapshot device config option is enabled
2) swap partition is used as resume device
In other circumstances the swap device is not writable from userspace.
In order to achieve this, every write attempt to a swap device is
checked against the device configured as part of the uswsusp API [0]
using a pointer to the inode struct in memory. If the swap device being
written was not configured for resuming, the write request is denied.
NOTE: this implementation works only for swap block devices, where the
inode configured by swapon (which sets S_SWAPFILE) is the same used
by SNAPSHOT_SET_SWAP_AREA.
In case of swap file, SNAPSHOT_SET_SWAP_AREA indeed receives the inode
of the block device containing the filesystem where the swap file is
located (+ offset in it) which is never passed to swapon and then has
not set S_SWAPFILE.
As result, the swap file itself (as a file) has never an option to be
written from userspace. Instead it remains writable if accessed directly
from the containing block device, which is always writeable from root.
[0] Documentation/power/userland-swsusp.rst
v2:
- rename is_hibernate_snapshot_dev() to is_hibernate_resume_dev()
- fix description so to correctly refer to the resume device
Signed-off-by: Domenico Andreoli <domenico.andreoli@linux.com>
Acked-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ARCH_SAVE_PAGE_KEYS has been introduced in order to be able to save
and restore s390 specific storage keys into a hibernation image.
With hibernation support removed from s390 there is no point in
keeping the callbacks.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
It is theoretically possible for the ACPI EC GPE to be set after the
s2idle_ops->wake() called from s2idle_loop() has returned and before
the subsequent pm_wakeup_pending() check is carried out. If that
happens, the resulting wakeup event will cause the system to resume
even though it may be a spurious one.
To avoid that race, first make the ->wake() callback in struct
platform_s2idle_ops return a bool value indicating whether or not
to let the system resume and rearrange s2idle_loop() to use that
value instad of the direct pm_wakeup_pending() call if ->wake() is
present.
Next, rework acpi_s2idle_wake() to process EC events and check
pm_wakeup_pending() before re-arming the SCI for system wakeup
to prevent it from triggering prematurely and add comments to
that function to explain the rationale for the new code flow.
Fixes: 56b9918490 ("PM: sleep: Simplify suspend-to-idle control flow")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The sysfs attribute `/sys/power/sync_on_suspend` controls, whether or not
filesystems are synced by the kernel before system suspend.
Congruously, the behaviour of build-time switch CONFIG_SUSPEND_SKIP_SYNC
is slightly changed: It now defines the run-tim default for the new sysfs
attribute `/sys/power/sync_on_suspend`.
The run-time attribute is added because the existing corresponding
build-time Kconfig flag for (`CONFIG_SUSPEND_SKIP_SYNC`) is not flexible
enough. E.g. Linux distributions that provide pre-compiled kernels
usually want to stick with the default (sync filesystems before suspend)
but under special conditions this needs to be changed.
One example for such a special condition is user-space handling of
suspending block devices (e.g. using `cryptsetup luksSuspend` or `dmsetup
suspend`) before system suspend. The Kernel trying to sync filesystems
after the underlying block device already got suspended obviously leads
to dead-locks. Be aware that you have to take care of the filesystem sync
yourself before suspending the system in those scenarios.
Signed-off-by: Jonas Meurer <jonas@freesources.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
According to Section 3.5 of the "Intel Low Power S0 Idle" document [1],
Function 5 of the LPS0 _DSM is expected to be invoked when the system
configuration matches the criteria for entering the target low-power
state of the platform. In particular, this means that all devices
should be suspended and in low-power states already when that function
is invoked.
This is not the case currently, however, because Function 5 of the
LPS0 _DSM is invoked by it before the "noirq" phase of device suspend,
which means that some devices may not have been put into low-power
states yet at that point. That is a consequence of the previous
design of the suspend-to-idle flow that allowed the "noirq" phase of
device suspend and the "noirq" phase of device resume to be carried
out for multiple times while "suspended" (if any spurious wakeup
events were detected) and the point of the LPS0 _DSM Function 5
invocation was chosen so as to call it (and LPS0 _DSM Function 6
analogously) once per suspend-resume cycle (regardless of how many
times the "noirq" phases of device suspend and resume were carried
out while "suspended").
Now that the suspend-to-idle flow has been redesigned to carry out
the "noirq" phases of device suspend and resume once in each cycle,
the code can be reordered to follow the specification that it is
based on more closely.
For this purpose, add ->prepare_late and ->restore_early platform
callbacks for suspend-to-idle, to be executed, respectively, after
the "noirq" phase of suspending devices and before the "noirq"
phase of resuming them and make ACPI use them for the invocation
of LPS0 _DSM functions as appropriate.
While at it, move the LPS0 entry requirements check to be made
before invoking Functions 3 and 5 of the LPS0 _DSM (also once
per cycle) as follows from the specification [1].
Link: https://uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf # [1]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
The EC GPE needs to be set up for system wakeup only if there is a
driver depending on it, either intel-hid or intel-vbtn, bound to a
button device that is expected to wake up the system from sleep (such
as the power button on some Dell systems, like the XPS13 9360). It
doesn't need to be set up for waking up the system from sleep in any
other cases and whether or not it is expected to wake up the system
from sleep doesn't depend on whether or not the LPS0 device is
present in the ACPI namespace.
For this reason, rearrange the ACPI suspend-to-idle code to make the
drivers depending on the EC GPE wakeup take care of setting it up and
decouple that from the LPS0 device handling.
While at it, make intel-hid and intel-vbtn prepare for system wakeup
only if they are allowed to wake up the system from sleep by user
space (via sysfs).
[Note that acpi_ec_mark_gpe_for_wake() and acpi_ec_set_gpe_wake_mask()
are there to prevent the EC GPE from being disabled by the
acpi_enable_all_wakeup_gpes() call in acpi_s2idle_prepare(), so on
systems with either intel-hid or intel-vbtn this change doesn't
affect any interactions with the hardware or platform firmware.]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
After commit 33e4f80ee6 ("ACPI / PM: Ignore spurious SCI wakeups
from suspend-to-idle") the "noirq" phases of device suspend and
resume may run for multiple times during suspend-to-idle, if there
are spurious system wakeup events while suspended. However, this
is complicated and fragile and actually unnecessary.
The main reason for doing this is that on some systems the EC may
signal system wakeup events (power button events, for example) as
well as events that should not cause the system to resume (spurious
system wakeup events). Thus, in order to determine whether or not
a given event signaled by the EC while suspended is a proper system
wakeup one, the EC GPE needs to be dispatched and to start with that
was achieved by allowing the ACPI SCI action handler to run, which
was only possible after calling resume_device_irqs().
However, dispatching the EC GPE this way turned out to take too much
time in some cases and some EC events might be missed due to that, so
commit 68e2201185 ("ACPI: EC: Dispatch the EC GPE directly on
s2idle wake") started to dispatch the EC GPE right after a wakeup
event has been detected, so in fact the full ACPI SCI action handler
doesn't need to run any more to deal with the wakeups coming from the
EC.
Use this observation to simplify the suspend-to-idle control flow
so that the "noirq" phases of device suspend and resume are each
run only once in every suspend-to-idle cycle, which is reported to
significantly reduce power drawn by some systems when suspended to
idle (by allowing them to reach a deep platform-wide low-power state
through the suspend-to-idle flow). [What appears to happen is that
the "noirq" resume of devices after a spurious EC wakeup brings some
devices into a state in which they prevent the platform from reaching
the deep low-power state going forward, even after a subsequent
"noirq" suspend phase, and on some systems the EC triggers such
wakeups already when the "noirq" suspend of devices is running for
the first time in the given suspend/resume cycle, so the platform
cannot reach the deep low-power state at all.]
First, make acpi_s2idle_wake() use the acpi_ec_dispatch_gpe() return
value to determine whether or not the wakeup may have been triggered
by the EC (in which case the system wakeup is canceled and ACPI
events are processed in order to determine whether or not the event
is a proper system wakeup one) and use rearm_wake_irq() (introduced
by a previous change) in it to rearm the ACPI SCI for system wakeup
detection in case the system will remain suspended.
Second, drop acpi_s2idle_sync(), which is not needed any more, and
the corresponding global platform suspend-to-idle callback.
Next, drop the pm_wakeup_pending() check (which is an optimization
only) from __device_suspend_noirq() to prevent it from returning
errors on system wakeups occurring before the "noirq" phase of
device suspend is complete (as in the case of suspend-to-idle it is
not known whether or not these wakeups are suprious at that point),
in order to avoid having to carry out a "noirq" resume of devices
on a spurious system wakeup.
Finally, change the code flow in s2idle_loop() to (1) run the
"noirq" suspend of devices once before starting the loop, (2) check
for spurious EC wakeups (via the platform ->wake callback) for the
first time before calling s2idle_enter(), and (3) run the "noirq"
resume of devices once after leaving the loop.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
* pm-sleep:
PM: sleep: Drop dev_pm_skip_next_resume_phases()
ACPI: PM: Drop unused function and function header
ACPI: PM: Introduce "poweroff" callbacks for ACPI PM domain and LPSS
ACPI: PM: Simplify and fix PM domain hibernation callbacks
PCI: PM: Simplify bus-level hibernation callbacks
PM: ACPI/PCI: Resume all devices during hibernation
kernel: power: swap: use kzalloc() instead of kmalloc() followed by memset()
PM: sleep: Update struct wakeup_source documentation
drivers: base: power: remove wakeup_sources_stats_dentry variable
PM: suspend: Rename pm_suspend_via_s2idle()
PM: sleep: Show how long dpm_suspend_start() and dpm_suspend_end() take
PM: hibernate: powerpc: Expose pfn_is_nosave() prototype
There are platforms that do not call pm_set_suspend_via_firmware(),
so pm_suspend_via_firmware() returns 'false' on them, but the power
states of PCI devices (PCIe ports in particular) are changed as a
result of powering down core platform components during system-wide
suspend. Thus the pm_suspend_via_firmware() checks in
pci_pm_suspend_noirq() and pci_pm_resume_noirq() introduced by
commit 3e26c5feed ("PCI: PM: Skip devices in D0 for suspend-to-
idle") are not sufficient to determine that devices left in D0
during suspend will remain in D0 during resume and so the bus-level
power management can be skipped for them.
For this reason, introduce a new global suspend flag,
PM_SUSPEND_FLAG_NO_PLATFORM, set it for suspend-to-idle only
and replace the pm_suspend_via_firmware() checks mentioned above
with checks against this flag.
Fixes: 3e26c5feed ("PCI: PM: Skip devices in D0 for suspend-to-idle")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
The name of pm_suspend_via_s2idle() is confusing, as it doesn't
reflect the purpose of the function precisely enough and it is
very similar to pm_suspend_via_firmware(), which has a different
purpose, so rename it as pm_suspend_default_s2idle() and update
its only caller, i8042_register_ports(), accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
The declaration for pfn_is_nosave is only available in
kernel/power/power.h. Since this function can be override in arch,
expose it globally. Having a prototype will make sure to avoid warning
(sometime treated as error with W=1) such as:
arch/powerpc/kernel/suspend.c:18:5: error: no previous prototype for 'pfn_is_nosave' [-Werror=missing-prototypes]
This moves the declaration into a globally visible header file and add
missing include to avoid a warning on powerpc.
Also remove the duplicated prototypes since not required anymore.
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add kerneldoc comments to pm_suspend_via_firmware(),
pm_resume_via_firmware() and pm_suspend_via_s2idle()
to explain what they do.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On systems with ACPI platform firmware the last stage of hibernation
is analogous to system suspend to S3 (suspend-to-RAM), so it should
be handled analogously. In particular, pm_suspend_via_firmware()
should return 'true' in that stage to let the callers of it know that
control will be passed to the platform firmware going forward, so
pm_set_suspend_via_firmware() needs to be called then in analogy with
acpi_suspend_begin().
However, the platform hibernation ->begin() callback is invoked
during the "freeze" transition (before creating a snapshot image of
system memory) as well as during the "hibernate" transition which is
the last stage of it and pm_set_suspend_via_firmware() should be
invoked by that callback in the latter stage only.
In order to implement that redefine the hibernation ->begin()
callback to take a pm_message_t argument to indicate which stage
of hibernation is taking place and rework acpi_hibernation_begin()
and acpi_hibernation_begin_old() to take it into account as needed.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Create a common helper to sync filesystems for system suspend and
hibernation.
Signed-off-by: Harry Pan <harry.pan@intel.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Dmitry writes:
"Input updates for v4.19-rc7
- we added a few scheduling points into various input interfaces to
ensure that large writes will not cause RCU stalls
- fixed configuring PS/2 keyboards as wakeup devices on newer
platforms
- added a new Xbox gamepad ID."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: uinput - add a schedule point in uinput_inject_events()
Input: evdev - add a schedule point in evdev_write()
Input: mousedev - add a schedule point in mousedev_write()
Input: i8042 - enable keyboard wakeups by default when s2idle is used
Input: xpad - add support for Xbox1 PDP Camo series gamepad
Previously, on typical consumer laptops, pressing a key on the keyboard
when the system is in suspend would cause it to wake up (default or
unconditional behaviour). This happens because the EC generates a SCI
interrupt in this scenario.
That is no longer true on modern laptops based on Intel WhiskeyLake,
including Acer Swift SF314-55G, Asus UX333FA, Asus UX433FN and Asus
UX533FD. We confirmed with Asus EC engineers that the "Modern Standby"
design has been modified so that the EC no longer generates a SCI
in this case; the keyboard controller itself should be used for wakeup.
In order to retain the standard behaviour of being able to use the
keyboard to wake up the system, enable serio wakeups by default on
platforms that are using s2idle.
Link: https://lkml.kernel.org/r/CAB4CAwfQ0mPMqCLp95TVjw4J0r5zKPWkSvvkK4cpZUGE--w8bQ@mail.gmail.com
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Daniel Drake <drake@endlessm.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
At present, "systemctl suspend" and "shutdown" can run in parrallel. A
system can suspend after devices_shutdown(), and resume. Then the shutdown
task goes on to power off. This causes many devices are not really shut
off. Hence replacing reboot_mutex with system_transition_mutex (renamed
from pm_mutex) to achieve the exclusion. The renaming of pm_mutex as
system_transition_mutex can be better to reflect the purpose of the mutex.
Signed-off-by: Pingfan Liu <kernelfans@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The declaration for swsusp_arch_resume marks it as 'asmlinkage', but the
definition in x86-32 does not, and it fails to include the header with the
declaration. This leads to a warning when building with
link-time-optimizations:
kernel/power/power.h:108:23: error: type of 'swsusp_arch_resume' does not match original declaration [-Werror=lto-type-mismatch]
extern asmlinkage int swsusp_arch_resume(void);
^
arch/x86/power/hibernate_32.c:148:0: note: 'swsusp_arch_resume' was previously declared here
int swsusp_arch_resume(void)
This moves the declaration into a globally visible header file and fixes up
both x86 definitions to match it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Len Brown <len.brown@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: linux-pm@vger.kernel.org
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Link: https://lkml.kernel.org/r/20180202145634.200291-2-arnd@arndb.de
Since pm_mutex is not exported using lock/unlock_system_sleep() from
inside a kernel module causes a "pm_mutex undefined" linker error.
Hence move lock/unlock_system_sleep() into kernel/power/main.c and
export these.
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
