To avoid some undesirable interactions between thermal zone suspend
and resume with user space that is running when those operations are
carried out, move them closer to the suspend and resume of devices,
respectively, by updating dpm_prepare() to carry out thermal zone
suspend and dpm_complete() to start thermal zone resume (that will
continue asynchronously).
This also makes the code easier to follow by removing one, arguably
redundant, level of indirection represented by the thermal PM notifier.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Armin Wolf <W_Armin@gmx.de>
Link: https://patch.msgid.link/2036875.PYKUYFuaPT@rafael.j.wysocki
Till now, the runtime PM workqueue has been flagged as freezable, so it
does not process work items during system-wide PM transitions like
system suspend and resume. The original reason to do that was to
reduce the likelihood of runtime PM getting in the way of system-wide
PM processing, but now it is mostly an optimization because (1) runtime
suspend of devices is prevented by bumping up their runtime PM usage
counters in device_prepare() and (2) device drivers are expected to
disable runtime PM for the devices handled by them before they embark
on system-wide PM activities that may change the state of the hardware
or otherwise interfere with runtime PM. However, it prevents
asynchronous runtime resume of devices from working during system-wide
PM transitions, which is confusing because synchronous runtime resume
is not prevented at the same time, and it also sometimes turns out to
be problematic.
For example, it has been reported that blk_queue_enter() may deadlock
during a system suspend transition because of the pm_request_resume()
usage in it [1]. It may also deadlock during a system resume transition
in a similar way. That happens because the asynchronous runtime resume
of the given device is not processed due to the freezing of the runtime
PM workqueue. While it may be better to address this particular issue
in the block layer, the very presence of it means that similar problems
may be expected to occur elsewhere.
For this reason, remove the WQ_FREEZABLE flag from the runtime PM
workqueue and make device_suspend_late() use the generic variant of
pm_runtime_disable() that will carry out runtime PM of the device
synchronously if there is pending resume work for it.
Also update the comment before the pm_runtime_disable() call in
device_suspend_late(), to document the fact that the runtime PM
should not be expected to work for the device until the end of
device_resume_early(), and update the related documentation.
This change may, even though it is not expected to, uncover some
latent issues related to queuing up asynchronous runtime resume
work items during system suspend or hibernation. However, they
should be limited to the interference between runtime resume and
system-wide PM callbacks in the cases when device drivers start
to handle system-wide PM before disabling runtime PM as described
above.
Link: https://lore.kernel.org/linux-pm/20251126101636.205505-2-yang.yang@vivo.com/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://patch.msgid.link/12794222.O9o76ZdvQC@rafael.j.wysocki
Pull pmdomain updates from Ulf Hansson:
"pmdomain core:
- Allow power-off for out-of-band wakeup-capable devices
- Drop the redundant call to dev_pm_domain_detach() for the amba bus
- Extend the genpd governor for CPUs to account for IPIs
pmdomain providers:
- bcm: Add support for BCM2712
- mediatek: Add support for MFlexGraphics power domains
- mediatek: Add support for MT8196 power domains
- qcom: Add RPMh power domain support for Kaanapali
- rockchip: Add support for RV1126B
pmdomain consumers:
- usb: dwc3: Enable out of band wakeup for i.MX95
- usb: chipidea: Enable out of band wakeup for i.MX95"
* tag 'pmdomain-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm: (26 commits)
pmdomain: Extend the genpd governor for CPUs to account for IPIs
smp: Introduce a helper function to check for pending IPIs
pmdomain: mediatek: convert from clk round_rate() to determine_rate()
amba: bus: Drop dev_pm_domain_detach() call
pmdomain: bcm: bcm2835-power: Prepare to support BCM2712
pmdomain: mediatek: mtk-mfg: select MAILBOX in Kconfig
pmdomain: mediatek: Add support for MFlexGraphics
pmdomain: mediatek: Fix build-errors
cpuidle: psci: Replace deprecated strcpy in psci_idle_init_cpu
pmdomain: rockchip: Add support for RV1126B
pmdomain: mediatek: Add support for MT8196 HFRPSYS power domains
pmdomain: mediatek: Add support for MT8196 SCPSYS power domains
pmdomain: mediatek: Add support for secure HWCCF infra power on
pmdomain: mediatek: Add support for Hardware Voter power domains
pmdomain: qcom: rpmhpd: Add RPMh power domain support for Kaanapali
usb: dwc3: imx8mp: Set out of band wakeup for i.MX95
usb: chipidea: ci_hdrc_imx: Set out of band wakeup for i.MX95
usb: chipidea: core: detach power domain for ci_hdrc platform device
pmdomain: core: Allow power-off for out-of-band wakeup-capable devices
PM: wakeup: Add out-of-band system wakeup support for devices
...
Some devices can wake up the system from suspend even when their power
domains are turned off. This is possible because their system-wakeup logic
resides in an always-on power domain - indicating that they support
out-of-band system wakeup.
Currently, PM domain core doesn't power off such devices if they are marked
as system wakeup sources. To better represent devices with out-of-band
wakeup capability, this patch introduces a new flag out_band_wakeup in
'struct dev_pm_info'.
Two helper APIs are added:
- device_set_out_band_wakeup() - to mark a device as having out-of-band
wakeup capability.
- device_out_band_wakeup() - to query the flag.
Allow the PM core and drivers to distinguish between regular and
out-of-band wakeup sources, enable more accurate power management decision.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Runtime PM should only be enabled in device_resume_early() if it has
been disabled for the given device by device_suspend_late(). Otherwise,
it may cause runtime PM callbacks to run prematurely in some cases
which leads to further functional issues.
Make two changes to address this problem.
First, reorder device_suspend_late() to only disable runtime PM for a
device when it is going to look for the device's callback or if the
device is a "syscore" one. In all of the other cases, disabling runtime
PM for the device is not in fact necessary. However, if the device's
callback returns an error and the power.is_late_suspended flag is not
going to be set, enable runtime PM so it only remains disabled when
power.is_late_suspended is set.
Second, make device_resume_early() only enable runtime PM for the
devices with the power.is_late_suspended flag set.
Fixes: 443046d1ad ("PM: sleep: Make suspend of devices more asynchronous")
Reported-by: Rose Wu <ya-jou.wu@mediatek.com>
Closes: https://lore.kernel.org/linux-pm/70b25dca6f8c2756d78f076f4a7dee7edaaffc33.camel@mediatek.com/
Cc: 6.16+ <stable@vger.kernel.org> # 6.16+
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://patch.msgid.link/12784270.O9o76ZdvQC@rafael.j.wysocki
PMSG_POWEROFF will be used for the PM core to allow differentiating between
a hibernation or shutdown sequence when re-using callbacks for common code.
Hibernation is started by writing a hibernation method (such as 'platform'
'shutdown', or 'reboot') to use into /sys/power/disk and writing 'disk' to
/sys/power/state.
Shutdown is initiated with the reboot() syscall with arguments on whether
to halt the system or power it off.
Tested-by: Eric Naim <dnaim@cachyos.org>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Link: https://patch.msgid.link/20251112224025.2051702-2-superm1@kernel.org
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge runtime PM framework updates and a core power management code fix
for 6.18-rc1:
- Make pm_runtime_put*() family of functions return 1 when the
given device is already suspended which is consistent with the
documentation (Brian Norris)
- Add basic kunit tests for runtime PM API contracts and update return
values in kerneldoc coments for the runtime PM API (Brian Norris,
Dan Carpenter)
- Add auto-cleanup macros for runtime PM "resume and get" and "get
without resume" operations, use one of them in the PCI core and
drop the existing "free" macro introduced for similar purpose, but
somewhat cumbersome to use (Rafael Wysocki)
- Make the core power management code avoid waiting on device links
marked as SYNC_STATE_ONLY which is consistent with the handling of
those device links elsewhere (Pin-yen Lin)
* pm-core:
PM: sleep: Do not wait on SYNC_STATE_ONLY device links
* pm-runtime:
PM: runtime: Fix error checking for kunit_device_register()
PM: runtime: Introduce one more usage counter guard
PM: runtime: Drop DEFINE_FREE() for pm_runtime_put()
PCI/sysfs: Use runtime PM guard macro for auto-cleanup
PM: runtime: Add auto-cleanup macros for "resume and get" operations
PM: runtime: Update kerneldoc return codes
PM: runtime: Make put{,_sync}() return 1 when already suspended
PM: runtime: Add basic kunit tests for API contracts
Merge changes related to system sleep and runtime PM framework for
6.18-rc1:
- Annotate loops walking device links in the power management core
code as _srcu and add macros for walking device links to reduce the
likelihood of coding mistakes related to them (Rafael Wysocki)
- Document time units for *_time functions in the runtime PM API (Brian
Norris)
- Clear power.must_resume in noirq suspend error path to avoid resuming
a dependant device under a suspended parent or supplier (Rafael
Wysocki)
- Fix GFP mask handling during hybrid suspend and make the amdgpu
driver handle hybrid suspend correctly (Mario Limonciello, Rafael
Wysocki)
- Fix GFP mask handling after aborted hibernation in platform mode and
combine exit paths in power_down() to avoid code duplication (Rafael
Wysocki)
- Use vmalloc_array() and vcalloc() in the hibernation core to avoid
open-coded size computations (Qianfeng Rong)
- Fix typo in hibernation core code comment (Li Jun)
- Call pm_wakeup_clear() in the same place where other functions that do
bookkeeping prior to suspend_prepare() are called (Samuel Wu)
* pm-core:
PM: core: Add two macros for walking device links
PM: core: Annotate loops walking device links as _srcu
* pm-runtime:
PM: runtime: Documentation: ABI: Document time units for *_time
* pm-sleep:
PM: hibernate: Combine return paths in power_down()
PM: hibernate: Restrict GFP mask in power_down()
PM: hibernate: Fix pm_hibernation_mode_is_suspend() build breakage
drm/amd: Fix hybrid sleep
PM: hibernate: Add pm_hibernation_mode_is_suspend()
PM: hibernate: Fix hybrid-sleep
PM: sleep: core: Clear power.must_resume in noirq suspend error path
PM: sleep: Make pm_wakeup_clear() call more clear
PM: hibernate: Fix typo in memory bitmaps description comment
PM: hibernate: Use vmalloc_array() and vcalloc() to improve code
Device links with DL_FLAG_SYNC_STATE_ONLY should not affect system
suspend and resume, and functions like device_reorder_to_tail() and
device_link_add() don't try to reorder the consumers with that flag.
However, dpm_wait_for_consumers() and dpm_wait_for_suppliers() don't
check thas flag before triggering dpm_wait(), leading to potential hang
during suspend/resume.
This can be reproduced on MT8186 Corsola Chromebook with devicetree like:
usb-a-connector {
compatible = "usb-a-connector";
port {
usb_a_con: endpoint {
remote-endpoint = <&usb_hs>;
};
};
};
usb_host {
compatible = "mediatek,mt8186-xhci", "mediatek,mtk-xhci";
port {
usb_hs: endpoint {
remote-endpoint = <&usb_a_con>;
};
};
};
In this case, the two nodes form a cycle and a SYNC_STATE_ONLY devlink
between usb_host (supplier) and usb-a-connector (consumer) is created.
Address this by exporting device_link_flag_is_sync_state_only() and
making dpm_wait_for_consumers() and dpm_wait_for_suppliers() use it
when deciding if dpm_wait() should be called.
Fixes: 05ef983e0d ("driver core: Add device link support for SYNC_STATE_ONLY flag")
Signed-off-by: Pin-yen Lin <treapking@chromium.org>
Link: https://patch.msgid.link/20250926102320.4053167-1-treapking@chromium.org
[ rjw: Subject and changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add separate macros for walking links to suppliers and consumers of a
device to help device links users to avoid exposing the internals of
struct dev_links_info in their code and possible coding mistakes related
to that.
Accordingly, use the new macros to replace open-coded device links list
walks in the core power management code.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://patch.msgid.link/1944671.tdWV9SEqCh@rafael.j.wysocki
If system suspend is aborted in the "noirq" phase (for instance, due to
an error returned by one of the device callbacks), power.is_noirq_suspended
will not be set for some devices and device_resume_noirq() will return
early for them. Consequently, noirq resume callbacks will not run for
them at all because the noirq suspend callbacks have not run for them
yet.
If any of them has power.must_resume set and late suspend has been
skipped for it (due to power.smart_suspend), early resume should be
skipped for it either, or its state may become inconsistent (for
instance, if the early resume assumes that it will always follow
noirq resume).
Make that happen by clearing power.must_resume in device_resume_noirq()
for devices with power.is_noirq_suspended clear that have been left in
suspend by device_suspend_late(), which will subsequently cause
device_resume_early() to leave the device in suspend and avoid
changing its state.
Fixes: 0d4b54c6fe ("PM / core: Add LEAVE_SUSPENDED driver flag")
Link: https://lore.kernel.org/linux-pm/5d692b81-6f58-4e86-9cb0-ede69a09d799@rowland.harvard.edu/
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://patch.msgid.link/3381776.aeNJFYEL58@rafael.j.wysocki
Pull drm updates from Dave Airlie:
"Highlights:
- Intel xe enable Panthor Lake, started adding WildCat Lake
- amdgpu has a bunch of reset improvments along with the usual IP
updates
- msm got VM_BIND support which is important for vulkan sparse memory
- more drm_panic users
- gpusvm common code to handle a bunch of core SVM work outside
drivers.
Detail summary:
Changes outside drm subdirectory:
- 'shrink_shmem_memory()' for better shmem/hibernate interaction
- Rust support infrastructure:
- make ETIMEDOUT available
- add size constants up to SZ_2G
- add DMA coherent allocation bindings
- mtd driver for Intel GPU non-volatile storage
- i2c designware quirk for Intel xe
core:
- atomic helpers: tune enable/disable sequences
- add task info to wedge API
- refactor EDID quirks
- connector: move HDR sink to drm_display_info
- fourcc: half-float and 32-bit float formats
- mode_config: pass format info to simplify
dma-buf:
- heaps: Give CMA heap a stable name
ci:
- add device tree validation and kunit
displayport:
- change AUX DPCD access probe address
- add quirk for DPCD probe
- add panel replay definitions
- backlight control helpers
fbdev:
- make CONFIG_FIRMWARE_EDID available on all arches
fence:
- fix UAF issues
format-helper:
- improve tests
gpusvm:
- introduce devmem only flag for allocation
- add timeslicing support to GPU SVM
ttm:
- improve eviction
sched:
- tracing improvements
- kunit improvements
- memory leak fixes
- reset handling improvements
color mgmt:
- add hardware gamma LUT handling helpers
bridge:
- add destroy hook
- switch to reference counted drm_bridge allocations
- tc358767: convert to devm_drm_bridge_alloc
- improve CEC handling
panel:
- switch to reference counter drm_panel allocations
- fwnode panel lookup
- Huiling hl055fhv028c support
- Raspberry Pi 7" 720x1280 support
- edp: KDC KD116N3730A05, N160JCE-ELL CMN, N116BCJ-EAK
- simple: AUO P238HAN01
- st7701: Winstar wf40eswaa6mnn0
- visionox: rm69299-shift
- Renesas R61307, Renesas R69328 support
- DJN HX83112B
hdmi:
- add CEC handling
- YUV420 output support
xe:
- WildCat Lake support
- Enable PanthorLake by default
- mark BMG as SRIOV capable
- update firmware recommendations
- Expose media OA units
- aux-bux support for non-volatile memory
- MTD intel-dg driver for non-volatile memory
- Expose fan control and voltage regulator in sysfs
- restructure migration for multi-device
- Restore GuC submit UAF fix
- make GEM shrinker drm managed
- SRIOV VF Post-migration recovery of GGTT nodes
- W/A additions/reworks
- Prefetch support for svm ranges
- Don't allocate managed BO for each policy change
- HWMON fixes for BMG
- Create LRC BO without VM
- PCI ID updates
- make SLPC debugfs files optional
- rework eviction rejection of bound external BOs
- consolidate PAT programming logic for pre/post Xe2
- init changes for flicker-free boot
- Enable GuC Dynamic Inhibit Context switch
i915:
- drm_panic support for i915/xe
- initial flip queue off by default for LNL/PNL
- Wildcat Lake Display support
- Support for DSC fractional link bpp
- Support for simultaneous Panel Replay and Adaptive sync
- Support for PTL+ double buffer LUT
- initial PIPEDMC event handling
- drm_panel_follower support
- DPLL interface renames
- allocate struct intel_display dynamically
- flip queue preperation
- abstract DRAM detection better
- avoid GuC scheduling stalls
- remove DG1 force probe requirement
- fix MEI interrupt handler on RT kernels
- use backlight control helpers for eDP
- more shared display code refactoring
amdgpu:
- add userq slot to INFO ioctl
- SR-IOV hibernation support
- Suspend improvements
- Backlight improvements
- Use scaling for non-native eDP modes
- cleaner shader updates for GC 9.x
- Remove fence slab
- SDMA fw checks for userq support
- RAS updates
- DMCUB updates
- DP tunneling fixes
- Display idle D3 support
- Per queue reset improvements
- initial smartmux support
amdkfd:
- enable KFD on loongarch
- mtype fix for ext coherent system memory
radeon:
- CS validation additional GL extensions
- drop console lock during suspend/resume
- bump driver version
msm:
- VM BIND support
- CI: infrastructure updates
- UBWC single source of truth
- decouple GPU and KMS support
- DP: rework I/O accessors
- DPU: SM8750 support
- DSI: SM8750 support
- GPU: X1-45 support and speedbin support for X1-85
- MDSS: SM8750 support
nova:
- register! macro improvements
- DMA object abstraction
- VBIOS parser + fwsec lookup
- sysmem flush page support
- falcon: generic falcon boot code and HAL
- FWSEC-FRTS: fb setup and load/execute
ivpu:
- Add Wildcat Lake support
- Add turbo flag
ast:
- improve hardware generations implementation
imx:
- IMX8qxq Display Controller support
lima:
- Rockchip RK3528 GPU support
nouveau:
- fence handling cleanup
panfrost:
- MT8370 support
- bo labeling
- 64-bit register access
qaic:
- add RAS support
rockchip:
- convert inno_hdmi to a bridge
rz-du:
- add RZ/V2H(P) support
- MIPI-DSI DCS support
sitronix:
- ST7567 support
sun4i:
- add H616 support
tidss:
- add TI AM62L support
- AM65x OLDI bridge support
bochs:
- drm panic support
vkms:
- YUV and R* format support
- use faux device
vmwgfx:
- fence improvements
hyperv:
- move out of simple
- add drm_panic support"
* tag 'drm-next-2025-07-30' of https://gitlab.freedesktop.org/drm/kernel: (1479 commits)
drm/tidss: oldi: convert to devm_drm_bridge_alloc() API
drm/tidss: encoder: convert to devm_drm_bridge_alloc()
drm/amdgpu: move reset support type checks into the caller
drm/amdgpu/sdma7: re-emit unprocessed state on ring reset
drm/amdgpu/sdma6: re-emit unprocessed state on ring reset
drm/amdgpu/sdma5.2: re-emit unprocessed state on ring reset
drm/amdgpu/sdma5: re-emit unprocessed state on ring reset
drm/amdgpu/gfx12: re-emit unprocessed state on ring reset
drm/amdgpu/gfx11: re-emit unprocessed state on ring reset
drm/amdgpu/gfx10: re-emit unprocessed state on ring reset
drm/amdgpu/gfx9.4.3: re-emit unprocessed state on kcq reset
drm/amdgpu/gfx9: re-emit unprocessed state on kcq reset
drm/amdgpu: Add WARN_ON to the resource clear function
drm/amd/pm: Use cached metrics data on SMUv13.0.6
drm/amd/pm: Use cached data for min/max clocks
gpu: nova-core: fix bounds check in PmuLookupTableEntry::new
drm/amdgpu: Replace HQD terminology with slots naming
drm/amdgpu: Add user queue instance count in HW IP info
drm/amd/amdgpu: Add helper functions for isp buffers
drm/amd/amdgpu: Initialize swnode for ISP MFD device
...
Pull driver core updates from Danilo Krummrich:
"debugfs:
- Remove unneeded debugfs_file_{get,put}() instances
- Remove last remnants of debugfs_real_fops()
- Allow storing non-const void * in struct debugfs_inode_info::aux
sysfs:
- Switch back to attribute_group::bin_attrs (treewide)
- Switch back to bin_attribute::read()/write() (treewide)
- Constify internal references to 'struct bin_attribute'
Support cache-ids for device-tree systems:
- Add arch hook arch_compact_of_hwid()
- Use arch_compact_of_hwid() to compact MPIDR values on arm64
Rust:
- Device:
- Introduce CoreInternal device context (for bus internal methods)
- Provide generic drvdata accessors for bus devices
- Provide Driver::unbind() callbacks
- Use the infrastructure above for auxiliary, PCI and platform
- Implement Device::as_bound()
- Rename Device::as_ref() to Device::from_raw() (treewide)
- Implement fwnode and device property abstractions
- Implement example usage in the Rust platform sample driver
- Devres:
- Remove the inner reference count (Arc) and use pin-init instead
- Replace Devres::new_foreign_owned() with devres::register()
- Require T to be Send in Devres<T>
- Initialize the data kept inside a Devres last
- Provide an accessor for the Devres associated Device
- Device ID:
- Add support for ACPI device IDs and driver match tables
- Split up generic device ID infrastructure
- Use generic device ID infrastructure in net::phy
- DMA:
- Implement the dma::Device trait
- Add DMA mask accessors to dma::Device
- Implement dma::Device for PCI and platform devices
- Use DMA masks from the DMA sample module
- I/O:
- Implement abstraction for resource regions (struct resource)
- Implement resource-based ioremap() abstractions
- Provide platform device accessors for I/O (remap) requests
- Misc:
- Support fallible PinInit types in Revocable
- Implement Wrapper<T> for Opaque<T>
- Merge pin-init blanket dependencies (for Devres)
Misc:
- Fix OF node leak in auxiliary_device_create()
- Use util macros in device property iterators
- Improve kobject sample code
- Add device_link_test() for testing device link flags
- Fix typo in Documentation/ABI/testing/sysfs-kernel-address_bits
- Hint to prefer container_of_const() over container_of()"
* tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (84 commits)
rust: io: fix broken intra-doc links to `platform::Device`
rust: io: fix broken intra-doc link to missing `flags` module
rust: io: mem: enable IoRequest doc-tests
rust: platform: add resource accessors
rust: io: mem: add a generic iomem abstraction
rust: io: add resource abstraction
rust: samples: dma: set DMA mask
rust: platform: implement the `dma::Device` trait
rust: pci: implement the `dma::Device` trait
rust: dma: add DMA addressing capabilities
rust: dma: implement `dma::Device` trait
rust: net::phy Change module_phy_driver macro to use module_device_table macro
rust: net::phy represent DeviceId as transparent wrapper over mdio_device_id
rust: device_id: split out index support into a separate trait
device: rust: rename Device::as_ref() to Device::from_raw()
arm64: cacheinfo: Provide helper to compress MPIDR value into u32
cacheinfo: Add arch hook to compress CPU h/w id into 32 bits for cache-id
cacheinfo: Set cache 'id' based on DT data
container_of: Document container_of() is not to be used in new code
driver core: auxiliary bus: fix OF node leak
...
Notice that device_suspend_noirq(), device_suspend_late() and
device_suspend() all set async_error on errors, so they don't really
need to return a value. Accordingly, make them all void and use
async_error in their callers instead of their return values.
Moreover, since async_error is updated concurrently without locking
during asynchronous suspend and resume processing, use READ_ONCE() and
WRITE_ONCE() for accessing it in those places to ensure that all of the
accesses will be carried out as expected.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Saravana Kannan <saravanak@google.com>
Link: https://patch.msgid.link/6198088.lOV4Wx5bFT@rjwysocki.net
After commit aa7a9275ab ("PM: sleep: Suspend async parents after
suspending children"), the following scenario is possible:
1. Device A is async and it depends on device B that is sync.
2. Async suspend is scheduled for A before the processing of B is
started.
3. A is waiting for B.
4. In the meantime, an unrelated device fails to suspend and returns
an error.
5. The processing of B doesn't start at all and its power.completion is
not updated.
6. A is still waiting for B when async_synchronize_full() is called.
7. Deadlock ensues.
To prevent this from happening, update power.completion for all devices
on errors in all suspend phases, but do not do it directly for devices
that are already being processed or are waiting for the processing to
start because in those cases it may be necessary to wait for the
processing to actually complete before updating power.completion for
the device.
Fixes: aa7a9275ab ("PM: sleep: Suspend async parents after suspending children")
Fixes: 443046d1ad ("PM: sleep: Make suspend of devices more asynchronous")
Closes: https://lore.kernel.org/linux-pm/e13740a0-88f3-4a6f-920f-15805071a7d6@linaro.org/
Reported-and-tested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://patch.msgid.link/6191258.lOV4Wx5bFT@rjwysocki.net
dev_pm_ops.thaw() is called in following cases:
* normal case: after hibernation image has been created.
* error case 1: creation of a hibernation image has failed.
* error case 2: restoration from a hibernation image has failed.
For normal case, it is called mainly for resume storage devices for
saving the hibernation image. Other devices that are not involved
in the image saving do not need to resume the device. But since there's
no api to know which case thaw() is called, device drivers can't
conditionally resume device in thaw().
The new pm_hibernate_is_recovering() is such a api to query if thaw() is
called in normal case.
Signed-off-by: Samuel Zhang <guoqing.zhang@amd.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20250710062313.3226149-5-guoqing.zhang@amd.com
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Commit 12ffc3b151 ("PM: Restrict swap use to later in the suspend
sequence") changed two pm_restore_gfp_mask() calls in enter_state()
and hibernation_restore() into one pm_restore_gfp_mask() call in
dpm_resume_end(), but it put that call before the dpm_resume()
invocation which is too early (some swap-backing devices may not be
ready at that point).
Moreover, this code ordering change was not even mentioned in the
changelog of the commit mentioned above.
Address this by moving that call after the dpm_resume() one.
Fixes: 12ffc3b151 ("PM: Restrict swap use to later in the suspend sequence")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/2797018.mvXUDI8C0e@rjwysocki.net
Rafael J. Wysocki
Linus Torvalds
Peng FanandUlf Hansson
Mario Limonciello (AMD)andRafael J. Wysocki
Sergey SenozhatskyandRafael J. Wysocki
Pin-yen LinandRafael J. Wysocki
Johannes BergandRafael J. Wysocki
Samuel ZhangandMario Limonciello