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2025-10-01Merge tag 'linux_kselftest-kunit-6.18-rc1' of ↵Linus Torvalds2-12/+47
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kunit updates from Shuah Khan: - New parameterized test features KUnit parameterized tests supported two primary methods for getting parameters: - Defining custom logic within a generate_params() function. - Using the KUNIT_ARRAY_PARAM() and KUNIT_ARRAY_PARAM_DESC() macros with a pre-defined static array and passing the created *_gen_params() to KUNIT_CASE_PARAM(). These methods present limitations when dealing with dynamically generated parameter arrays, or in scenarios where populating parameters sequentially via generate_params() is inefficient or overly complex. These limitations are fixed with a parameterized test method - Fix issues in kunit build artifacts cleanup - Fix parsing skipped test problem in kselftest framework - Enable PCI on UML without triggering WARN() - a few other fixes and adds support for new configs such as MIPS * tag 'linux_kselftest-kunit-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: kunit: Extend kconfig help text for KUNIT_UML_PCI rust: kunit: allow `cfg` on `test`s kunit: qemu_configs: Add MIPS configurations kunit: Enable PCI on UML without triggering WARN() Documentation: kunit: Document new parameterized test features kunit: Add example parameterized test with direct dynamic parameter array setup kunit: Add example parameterized test with shared resource management using the Resource API kunit: Enable direct registration of parameter arrays to a KUnit test kunit: Pass parameterized test context to generate_params() kunit: Introduce param_init/exit for parameterized test context management kunit: Add parent kunit for parameterized test context kunit: tool: Accept --raw_output=full as an alias of 'all' kunit: tool: Parse skipped tests from kselftest.h kunit: Always descend into kunit directory during build
2025-10-01Merge tag 'pm-6.18-rc1' of ↵Linus Torvalds3-20/+16
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management updates from Rafael Wysocki: "The majority of these are cpufreq changes, which has been a recurring pattern for a few recent cycles. Those changes include new hardware support (AN7583 SoC support in the airoha cpufreq driver, ipq5424 support in the qcom-nvmem cpufreq driver, MT8196 support in the mediatek cpufreq driver, AM62D2 support in the ti cpufreq driver), DT bindings and Rust code updates, cleanups of the core and governors, and multiple driver fixes and cleanups. Beyond that, there are hibernation fixes (some remaining 6.16 cycle fallout and an issue related to hybrid suspend in the amdgpu driver), cleanups of the PM core code, runtime PM documentation update, cpuidle and power capping cleanups, and tooling updates. Specifics: - Rearrange variable declarations involving __free() in the cpufreq core and intel_pstate driver to follow common coding style (Rafael Wysocki) - Fix object lifecycle issue in update_qos_request(), rearrange freq QoS updates using __free(), and adjust frequency percentage computations in the intel_pstate driver (Rafael Wysocki) - Update intel_pstate to allow it to enable HWP without EPP if the new DEC (Dynamic Efficiency Control) HW feature is enabled (Rafael Wysocki) - Use on_each_cpu_mask() in drv_write() in the ACPI cpufreq driver to simplify the code (Rafael Wysocki) - Use likely() optimization in intel_pstate_sample() (Yaxiong Tian) - Remove dead EPB-related code from intel_pstate (Srinivas Pandruvada) - Use scope-based cleanup for cpufreq policy references in multiple cpufreq drivers (Zihuan Zhang) - Avoid calling get_governor() for the first policy in the cpufreq core to simplify the initial policy path (Zihuan Zhang) - Clean up the cpufreq core in multiple places (Zihuan Zhang) - Use int type to store negative error codes in the cpufreq core and update the speedstep-lib to use int for error codes (Qianfeng Rong) - Update the efficient idle check for Intel extended Families in the ondemand cpufreq governor (Sohil Mehta) - Replace sscanf() with kstrtouint() in the conservative cpufreq governor (Kaushlendra Kumar) - Rename CpumaskVar::as[_mut]_ref to from_raw[_mut] in the cpumask Rust code and mark CpumaskVar as transparent (Alice Ryhl, Baptiste Lepers) - Update ARef and AlwaysRefCounted imports from sync::aref in the OPP Rust code (Shankari Anand) - Add support for AN7583 SoC to the airoha cpufreq driver (Christian Marangi) - Enable cpufreq for ipq5424 in the qcom-nvmem cpufreq driver (Md Sadre Alam) - Add support for MT8196 to the mediatek-hw cpufreq driver, refactor that driver and add mediatek,mt8196-cpufreq-hw DT binding (Nicolas Frattaroli) - Avoid redundant conditions in the mediatek cpufreq driver (Liao Yuanhong) - Add support for AM62D2 to the ti cpufreq driver and blocklist ti,am62d2 SoC in dt-platdev (Paresh Bhagat) - Support more speed grades on AM62Px SoC in the ti cpufreq driver, allow all silicon revisions to support OPPs in it, and fix supported hardware for 1GHz OPP (Judith Mendez) - Add QCS615 compatible to DT bindings for cpufreq-qcom-hw (Taniya Das) - Minor assorted updates of the scmi, longhaul, CPPC, and armada-37xx cpufreq drivers (Akhilesh Patil, BowenYu, Dennis Beier, and Florian Fainelli) - Remove outdated cpufreq-dt.txt (Frank Li) - Fix python gnuplot package names in the amd_pstate_tracer utility (Kuan-Wei Chiu) - Saravana Kannan will maintain the virtual-cpufreq driver (Saravana Kannan) - Prevent CPU capacity updates after registering a perf domain from failing on a first CPU that is not present (Christian Loehle) - Add support for the cases in which frequency alone is not sufficient to uniquely identify an OPP (Krishna Chaitanya Chundru) - Use to_result() for OPP error handling in Rust (Onur Özkan) - Add support for LPDDR5 on Rockhip RK3588 SoC to rockchip-dfi devfreq driver (Nicolas Frattaroli) - Fix an issue where DDR cycle counts on RK3588/RK3528 with LPDDR4(X) are reported as half by adding a cycle multiplier to the DFI driver in rockchip-dfi devfreq-event driver (Nicolas Frattaroli) - Fix missing error pointer dereference check of regulator instance in the mtk-cci devfreq driver probe and remove a redundant condition from an if () statement in that driver (Dan Carpenter, Liao Yuanhong) - Fail cpuidle device registration if there is one already to avoid sysfs-related issues (Rafael Wysocki) - Use sysfs_emit()/sysfs_emit_at() instead of sprintf()/scnprintf() in cpuidle (Vivek Yadav) - Fix device and OF node leaks at probe in the qcom-spm cpuidle driver and drop unnecessary initialisations from it (Johan Hovold) - Remove unnecessary address-of operators from the intel_idle cpuidle driver (Kaushlendra Kumar) - Rearrange main loop in menu_select() to make the code in that funtion easier to follow (Rafael Wysocki) - Convert values in microseconds to ktime using us_to_ktime() where applicable in the intel_idle power capping driver (Xichao Zhao) - 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) - Fix and clean up the x86_energy_perf_policy utility and update its documentation (Len Brown, Kaushlendra Kumar) - Fix incorrect sorting of PMT telemetry in turbostat (Kaushlendra Kumar) - Fix incorrect size in cpuidle_state_disable() and the error return value of cpupower_write_sysfs() in cpupower (Kaushlendra Kumar)" * tag 'pm-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (86 commits) 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 PM: runtime: Documentation: ABI: Document time units for *_time tools/power x86_energy_perf_policy.8: Emphasize preference for SW interfaces tools/power x86_energy_perf_policy: Add make snapshot target tools/power x86_energy_perf_policy: Prefer driver HWP limits tools/power x86_energy_perf_policy: EPB access is only via sysfs tools/power x86_energy_perf_policy: Prepare for MSR/sysfs refactoring tools/power x86_energy_perf_policy: Enhance HWP enable tools/power x86_energy_perf_policy: Enhance HWP enabled check tools/power x86_energy_perf_policy: Fix incorrect fopen mode usage tools/power turbostat: Fix incorrect sorting of PMT telemetry drm/amd: Fix hybrid sleep PM: hibernate: Add pm_hibernation_mode_is_suspend() PM: hibernate: Fix hybrid-sleep tools/cpupower: Fix incorrect size in cpuidle_state_disable() tools/power/x86/amd_pstate_tracer: Fix python gnuplot package names cpufreq: Replace pointer subtraction with iteration macro cpuidle: Fail cpuidle device registration if there is one already ...
2025-10-01Merge tag 'regulator-v6.18' of ↵Linus Torvalds2-97/+84
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator Pull regulator updates from Mark Brown: "This is a very quiet release for regulator, almost all the changes are new drivers but we do also have some improvements for the Rust bindings. - Additional APIs added to the Rust bindings - Support for Maxim MAX77838, NXP PF0900 and PF5300, Richtek RT5133 and SpacemiT P1" * tag 'regulator-v6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (28 commits) regulator: dt-bindings: qcom,sdm845-refgen-regulator: document more platforms regulator: Fix MAX77838 selection regulator: spacemit: support SpacemiT P1 regulators regulator: max77838: add max77838 regulator driver dt-bindings: regulator: document max77838 pmic rust: regulator: add devm_enable and devm_enable_optional rust: regulator: remove Regulator<Dynamic> regulator: dt-bindings: rpi-panel: Split 7" Raspberry Pi 720x1280 v2 binding regulator: pf530x: Add a driver for the NXP PF5300 Regulator regulator: dt-bindings: nxp,pf530x: Add NXP PF5300/PF5301/PF5302 PMICs regulator: scmi: Use int type to store negative error codes regulator: core: Remove redundant ternary operators rust: regulator: use `to_result` for error handling regulator: consumer.rst: document bulk operations regulator: rt5133: Fix IS_ERR() vs NULL bug in rt5133_validate_vendor_info() regulator: bd718x7: Use kcalloc() instead of kzalloc() regulator: rt5133: Fix spelling mistake "regualtor" -> "regulator" regulator: remove unneeded 'fast_io' parameter in regmap_config regulator: rt5133: Add RT5133 PMIC regulator Support regulator: dt-bindings: Add Richtek RT5133 Support ...
2025-10-01Merge tag 'driver-core-6.18-rc1' of ↵Linus Torvalds23-25/+2971
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "Auxiliary: - Drop call to dev_pm_domain_detach() in auxiliary_bus_probe() - Optimize logic of auxiliary_match_id() Rust: - Auxiliary: - Use primitive C types from prelude - DebugFs: - Add debugfs support for simple read/write files and custom callbacks through a File-type-based and directory-scope-based API - Sample driver code for the File-type-based API - Sample module code for the directory-scope-based API - I/O: - Add io::poll module and implement Rust specific read_poll_timeout() helper - IRQ: - Implement support for threaded and non-threaded device IRQs based on (&Device<Bound>, IRQ number) tuples (IrqRequest) - Provide &Device<Bound> cookie in IRQ handlers - PCI: - Support IRQ requests from IRQ vectors for a specific pci::Device<Bound> - Implement accessors for subsystem IDs, revision, devid and resource start - Provide dedicated pci::Vendor and pci::Class types for vendor and class ID numbers - Implement Display to print actual vendor and class names; Debug to print the raw ID numbers - Add pci::DeviceId::from_class_and_vendor() helper - Use primitive C types from prelude - Various minor inline and (safety) comment improvements - Platform: - Support IRQ requests from IRQ vectors for a specific platform::Device<Bound> - Nova: - Use pci::DeviceId::from_class_and_vendor() to avoid probing non-display/compute PCI functions - Misc: - Add helper for cpu_relax() - Update ARef import from sync::aref sysfs: - Remove bin_attrs_new field from struct attribute_group - Remove read_new() and write_new() from struct bin_attribute Misc: - Document potential race condition in get_dev_from_fwnode() - Constify node_group argument in software node registration functions - Fix order of kernel-doc parameters in various functions - Set power.no_pm flag for faux devices - Set power.no_callbacks flag along with the power.no_pm flag - Constify the pmu_bus bus type - Minor spelling fixes" * tag 'driver-core-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (43 commits) rust: pci: display symbolic PCI vendor names rust: pci: display symbolic PCI class names rust: pci: fix incorrect platform reference in PCI driver probe doc comment rust: pci: fix incorrect platform reference in PCI driver unbind doc comment perf: make pmu_bus const samples: rust: Add scoped debugfs sample driver rust: debugfs: Add support for scoped directories samples: rust: Add debugfs sample driver rust: debugfs: Add support for callback-based files rust: debugfs: Add support for writable files rust: debugfs: Add support for read-only files rust: debugfs: Add initial support for directories driver core: auxiliary bus: Optimize logic of auxiliary_match_id() driver core: auxiliary bus: Drop dev_pm_domain_detach() call driver core: Fix order of the kernel-doc parameters driver core: get_dev_from_fwnode(): document potential race drivers: base: fix "publically"->"publicly" driver core/PM: Set power.no_callbacks along with power.no_pm driver core: faux: Set power.no_pm for faux devices rust: pci: inline several tiny functions ...
2025-10-01cpufreq: Make drivers using CPUFREQ_ETERNAL specify transition latencyRafael J. Wysocki1-3/+4
Commit a755d0e2d41b ("cpufreq: Honour transition_latency over transition_delay_us") caused platforms where cpuinfo.transition_latency is CPUFREQ_ETERNAL to get a very large transition latency whereas previously it had been capped at 10 ms (and later at 2 ms). This led to a user-observable regression between 6.6 and 6.12 as described by Shawn: "The dbs sampling_rate was 10000 us on 6.6 and suddently becomes 6442450 us (4294967295 / 1000 * 1.5) on 6.12 for these platforms because the default transition delay was dropped [...]. It slows down dbs governor's reacting to CPU loading change dramatically. Also, as transition_delay_us is used by schedutil governor as rate_limit_us, it shows a negative impact on device idle power consumption, because the device gets slightly less time in the lowest OPP." Evidently, the expectation of the drivers using CPUFREQ_ETERNAL as cpuinfo.transition_latency was that it would be capped by the core, but they may as well return a default transition latency value instead of CPUFREQ_ETERNAL and the core need not do anything with it. Accordingly, introduce CPUFREQ_DEFAULT_TRANSITION_LATENCY_NS and make all of the drivers in question use it instead of CPUFREQ_ETERNAL. Also update the related Rust binding. Fixes: a755d0e2d41b ("cpufreq: Honour transition_latency over transition_delay_us") Closes: https://lore.kernel.org/linux-pm/20250922125929.453444-1-shawnguo2@yeah.net/ Reported-by: Shawn Guo <shawnguo@kernel.org> Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org> Reviewed-by: Jie Zhan <zhanjie9@hisilicon.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 6.6+ <stable@vger.kernel.org> # 6.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Link: https://patch.msgid.link/2264949.irdbgypaU6@rafael.j.wysocki [ rjw: Fix typo in new symbol name, drop redundant type cast from Rust binding ] Tested-by: Shawn Guo <shawnguo@kernel.org> # with cpufreq-dt driver Reviewed-by: Qais Yousef <qyousef@layalina.io> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-09-30Merge tag 'rust-6.18' of ↵Linus Torvalds50-297/+1038
git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux Pull rust updates from Miguel Ojeda: "Toolchain and infrastructure: - Derive 'Zeroable' for all structs and unions generated by 'bindgen' where possible and corresponding cleanups. To do so, add the 'pin-init' crate as a dependency to 'bindings' and 'uapi'. It also includes its first use in the 'cpufreq' module, with more to come in the next cycle. - Add warning to the 'rustdoc' target to detect broken 'srctree/' links and fix existing cases. - Remove support for unused (since v6.16) host '#[test]'s, simplifying the 'rusttest' target. Tests should generally run within KUnit. 'kernel' crate: - Add 'ptr' module with a new 'Alignment' type, which is always a power of two and is used to validate that a given value is a valid alignment and to perform masking and alignment operations: // Checked at build time. assert_eq!(Alignment::new::<16>().as_usize(), 16); // Checked at runtime. assert_eq!(Alignment::new_checked(15), None); assert_eq!(Alignment::of::<u8>().log2(), 0); assert_eq!(0x25u8.align_down(Alignment::new::<0x10>()), 0x20); assert_eq!(0x5u8.align_up(Alignment::new::<0x10>()), Some(0x10)); assert_eq!(u8::MAX.align_up(Alignment::new::<0x10>()), None); It also includes its first use in Nova. - Add 'core::mem::{align,size}_of{,_val}' to the prelude, matching Rust 1.80.0. - Keep going with the steps on our migration to the standard library 'core::ffi::CStr' type (use 'kernel::{fmt, prelude::fmt!}' and use upstream method names). - 'error' module: improve 'Error::from_errno' and 'to_result' documentation, including examples/tests. - 'sync' module: extend 'aref' submodule documentation now that it exists, and more updates to complete the ongoing move of 'ARef' and 'AlwaysRefCounted' to 'sync::aref'. - 'list' module: add an example/test for 'ListLinksSelfPtr' usage. - 'alloc' module: - Implement 'Box::pin_slice()', which constructs a pinned slice of elements. - Provide information about the minimum alignment guarantees of 'Kmalloc', 'Vmalloc' and 'KVmalloc'. - Take minimum alignment guarantees of allocators for 'ForeignOwnable' into account. - Remove the 'allocator_test' (including 'Cmalloc'). - Add doctest for 'Vec::as_slice()'. - Constify various methods. - 'time' module: - Add methods on 'HrTimer' that can only be called with exclusive access to an unarmed timer, or from timer callback context. - Add arithmetic operations to 'Instant' and 'Delta'. - Add a few convenience and access methods to 'HrTimer' and 'Instant'. 'macros' crate: - Reduce collections in 'quote!' macro. And a few other cleanups and improvements" * tag 'rust-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (58 commits) gpu: nova-core: use Alignment for alignment-related operations rust: add `Alignment` type rust: macros: reduce collections in `quote!` macro rust: acpi: use `core::ffi::CStr` method names rust: of: use `core::ffi::CStr` method names rust: net: use `core::ffi::CStr` method names rust: miscdevice: use `core::ffi::CStr` method names rust: kunit: use `core::ffi::CStr` method names rust: firmware: use `core::ffi::CStr` method names rust: drm: use `core::ffi::CStr` method names rust: cpufreq: use `core::ffi::CStr` method names rust: configfs: use `core::ffi::CStr` method names rust: auxiliary: use `core::ffi::CStr` method names drm/panic: use `core::ffi::CStr` method names rust: device: use `kernel::{fmt,prelude::fmt!}` rust: sync: use `kernel::{fmt,prelude::fmt!}` rust: seq_file: use `kernel::{fmt,prelude::fmt!}` rust: kunit: use `kernel::{fmt,prelude::fmt!}` rust: file: use `kernel::{fmt,prelude::fmt!}` rust: device: use `kernel::{fmt,prelude::fmt!}` ...
2025-09-30Merge tag 'locking-core-2025-09-26' of ↵Linus Torvalds14-91/+2381
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "Mostly Rust runtime enhancements: - Add initial support for generic LKMM atomic variables in Rust (Boqun Feng) - Add the wrapper for `refcount_t` in Rust (Gary Guo) - Add a new reviewer, Gary Guo" * tag 'locking-core-2025-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: MAINTAINERS: update atomic infrastructure entry to include Rust rust: block: convert `block::mq` to use `Refcount` rust: convert `Arc` to use `Refcount` rust: make `Arc::into_unique_or_drop` associated function rust: implement `kernel::sync::Refcount` rust: sync: Add memory barriers rust: sync: atomic: Add Atomic<{usize,isize}> rust: sync: atomic: Add Atomic<u{32,64}> rust: sync: atomic: Add the framework of arithmetic operations rust: sync: atomic: Add atomic {cmp,}xchg operations rust: sync: atomic: Add generic atomics rust: sync: atomic: Add ordering annotation types rust: sync: Add basic atomic operation mapping framework rust: Introduce atomic API helpers
2025-09-30Merge tag 'lsm-pr-20250926' of ↵Linus Torvalds1-5/+1
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm Pull lsm updates from Paul Moore: - Move the management of the LSM BPF security blobs into the framework In order to enable multiple LSMs we need to allocate and free the various security blobs in the LSM framework and not the individual LSMs as they would end up stepping all over each other. - Leverage the lsm_bdev_alloc() helper in lsm_bdev_alloc() Make better use of our existing helper functions to reduce some code duplication. - Update the Rust cred code to use 'sync::aref' Part of a larger effort to move the Rust code over to the 'sync' module. - Make CONFIG_LSM dependent on CONFIG_SECURITY As the CONFIG_LSM Kconfig setting is an ordered list of the LSMs to enable a boot, it obviously doesn't make much sense to enable this when CONFIG_SECURITY is disabled. - Update the LSM and CREDENTIALS sections in MAINTAINERS with Rusty bits Add the Rust helper files to the associated LSM and CREDENTIALS entries int the MAINTAINERS file. We're trying to improve the communication between the two groups and making sure we're all aware of what is going on via cross-posting to the relevant lists is a good way to start. * tag 'lsm-pr-20250926' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm: lsm: CONFIG_LSM can depend on CONFIG_SECURITY MAINTAINERS: add the associated Rust helper to the CREDENTIALS section MAINTAINERS: add the associated Rust helper to the LSM section rust,cred: update AlwaysRefCounted import to sync::aref security: use umax() to improve code lsm,selinux: Add LSM blob support for BPF objects lsm: use lsm_blob_alloc() in lsm_bdev_alloc()
2025-09-29Merge tag 'vfs-6.18-rc1.rust' of ↵Linus Torvalds2-9/+6
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs rust updates from Christian Brauner: "This contains a few minor vfs rust changes: - Add the pid namespace Rust wrappers to the correct MAINTAINERS entry - Use to_result() in the Rust file error handling code - Update imports for fs and pid_namespce Rust wrappers" * tag 'vfs-6.18-rc1.rust' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: rust: file: use to_result for error handling pid: add Rust files to MAINTAINERS rust: fs: update ARef and AlwaysRefCounted imports from sync::aref rust: pid_namespace: update AlwaysRefCounted imports from sync::aref
2025-09-29Merge branches 'pm-em', 'pm-opp' and 'pm-devfreq'Rafael J. Wysocki1-11/+5
Merge energy model management, OPP (operating performance points) and devfreq updates for 6.18-rc1: - Prevent CPU capacity updates after registering a perf domain from failing on a first CPU that is not present (Christian Loehle) - Add support for the cases in which frequency alone is not sufficient to uniquely identify an OPP (Krishna Chaitanya Chundru) - Use to_result() for OPP error handling in Rust (Onur Özkan) - Add support for LPDDR5 on Rockhip RK3588 SoC to rockchip-dfi devfreq driver (Nicolas Frattaroli) - Fix an issue where DDR cycle counts on RK3588/RK3528 with LPDDR4(X) are reported as half by adding a cycle multiplier to the DFI driver in rockchip-dfi devfreq-event driver (Nicolas Frattaroli) - Fix missing error pointer dereference check of regulator instance in the mtk-cci devfreq driver probe and remove a redundant condition from an if () statement in that driver (Dan Carpenter, Liao Yuanhong) * pm-em: PM: EM: Fix late boot with holes in CPU topology * pm-opp: OPP: Add support to find OPP for a set of keys rust: opp: use to_result for error handling * pm-devfreq: PM / devfreq: rockchip-dfi: add support for LPDDR5 PM / devfreq: rockchip-dfi: double count on RK3588 PM / devfreq: mtk-cci: avoid redundant conditions PM / devfreq: mtk-cci: Fix potential error pointer dereference in probe()
2025-09-26rust: usb: keep usb::Device private for nowDanilo Krummrich1-1/+1
The USB abstractions target to support USB interface drivers. While internally the abstraction has to deal with the interface's parent USB device, there shouldn't be a need for users to deal with the parent USB device directly. Functions, such as for preparing and sending USB URBs, can be implemented for the usb::Interface structure directly. Whether this internal implementation has to deal with the parent USB device can remain transparent to USB interface drivers. Hence, keep the usb::Device structure private for now, in order to avoid confusion for users and to make it less likely to accidentally expose APIs with unnecessary indirections. Should we start supporting USB device drivers, or need it for any other reason we do not foresee yet, it should be trivial to make it public again. Signed-off-by: Danilo Krummrich <dakr@kernel.org> Link: https://lore.kernel.org/r/20250925190400.144699-2-dakr@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-26rust: usb: don't retain device context for the interface parentDanilo Krummrich1-6/+5
When deriving the parent USB device (struct usb_device) from a USB interface (struct usb_interface), do not retain the device context. For the Bound context, as pointed out by Alan in [1], it is not guaranteed that the parent USB device is always bound when the interface is bound. The bigger problem, however, is that we can't infer the Core context, since eventually it indicates that the device lock is held. However, there is no guarantee that if the device lock of the interface is held, also the device lock of the parent USB device is held. Hence, fix this by not inferring any device context information; while at it, fix up the (affected) safety comments. Link: https://lore.kernel.org/all/0ff2a825-1115-426a-a6f9-df544cd0c5fc@rowland.harvard.edu/ [1] Fixes: e7e2296b0ecf ("rust: usb: add basic USB abstractions") Signed-off-by: Danilo Krummrich <dakr@kernel.org> Link: https://lore.kernel.org/r/20250925190400.144699-1-dakr@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-25rust: pci: display symbolic PCI vendor namesJohn Hubbard1-7/+11
The Display implementation for Vendor was forwarding directly to Debug printing, resulting in raw hex values instead of PCI Vendor strings. Improve things by doing a stringify!() call for each PCI Vendor item. This now prints symbolic names such as "NVIDIA", instead of "Vendor(0x10de)". It still falls back to Debug formatting for unknown class values. Suggested-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> [ Remove #[inline] for Vendor::fmt(). - Danilo ] Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-09-25rust: pci: display symbolic PCI class namesJohn Hubbard1-6/+11
The Display implementation for Class was forwarding directly to Debug printing, resulting in raw hex values instead of PCI Class strings. Improve things by doing a stringify!() call for each PCI Class item. This now prints symbolic names such as "DISPLAY_VGA", instead of "Class(0x030000)". It still falls back to Debug formatting for unknown class values. Suggested-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: John Hubbard <jhubbard@nvidia.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Danilo Krummrich <dakr@kernel.org>
2025-09-25USB: disable rust bindings from the build for nowGreg Kroah-Hartman3-4/+0
The rust USB bindings as submitted are a good start, but they don't really seem to be correct in a number of minor places, so just disable them from the build entirely at this point in time. When they are ready to be re-enabled, this commit can be reverted. Acked-by: Daniel Almeida <daniel.almeida@collabora.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-24Merge back earlier cpufreq material for 6.18Rafael J. Wysocki3-9/+11
2025-09-24Merge patch series "Add generated modalias to modules.builtin.modinfo"Nathan Chancellor1-4/+4
Alexey Gladkov says: The modules.builtin.modinfo file is used by userspace (kmod to be specific) to get information about builtin modules. Among other information about the module, information about module aliases is stored. This is very important to determine that a particular modalias will be handled by a module that is inside the kernel. There are several mechanisms for creating modalias for modules: The first is to explicitly specify the MODULE_ALIAS of the macro. In this case, the aliases go into the '.modinfo' section of the module if it is compiled separately or into vmlinux.o if it is builtin into the kernel. The second is the use of MODULE_DEVICE_TABLE followed by the use of the modpost utility. In this case, vmlinux.o no longer has this information and does not get it into modules.builtin.modinfo. For example: $ modinfo pci:v00008086d0000A36Dsv00001043sd00008694bc0Csc03i30 modinfo: ERROR: Module pci:v00008086d0000A36Dsv00001043sd00008694bc0Csc03i30 not found. $ modinfo xhci_pci name: xhci_pci filename: (builtin) license: GPL file: drivers/usb/host/xhci-pci description: xHCI PCI Host Controller Driver The builtin module is missing alias "pci:v*d*sv*sd*bc0Csc03i30*" which will be generated by modpost if the module is built separately. To fix this it is necessary to add the generated by modpost modalias to modules.builtin.modinfo. Fortunately modpost already generates .vmlinux.export.c for exported symbols. It is possible to add `.modinfo` for builtin modules and modify the build system so that `.modinfo` section is extracted from the intermediate vmlinux after modpost is executed. Link: https://patch.msgid.link/cover.1758182101.git.legion@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2025-09-24modpost: Add modname to mod_device_table aliasAlexey Gladkov1-4/+4
At this point, if a symbol is compiled as part of the kernel, information about which module the symbol belongs to is lost. To save this it is possible to add the module name to the alias name. It's not very pretty, but it's possible for now. Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Andreas Hindborg <a.hindborg@kernel.org> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Alex Gaynor <alex.gaynor@gmail.com> Cc: rust-for-linux@vger.kernel.org Signed-off-by: Alexey Gladkov <legion@kernel.org> Acked-by: Danilo Krummrich <dakr@kernel.org> Acked-by: Nicolas Schier <nsc@kernel.org> Link: https://patch.msgid.link/1a0d0bd87a4981d465b9ed21e14f4e78eaa03ded.1758182101.git.legion@kernel.org Signed-off-by: Nathan Chancellor <nathan@kernel.org>
2025-09-24rust: usb: add basic USB abstractionsDaniel Almeida5-0/+469
Add basic USB abstractions, consisting of usb::{Device, Interface, Driver, Adapter, DeviceId} and the module_usb_driver macro. This is the first step in being able to write USB device drivers, which paves the way for USB media drivers - for example - among others. This initial support will then be used by a subsequent sample driver, which constitutes the only user of the USB abstractions so far. Signed-off-by: Daniel Almeida <daniel.almeida@collabora.com> Link: https://lore.kernel.org/r/20250825-b4-usb-v1-1-7aa024de7ae8@collabora.com [ force USB = y for now - gregkh ] Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-09-22rust: add `Alignment` typeAlexandre Courbot2-0/+231
Alignment operations are very common in the kernel. Since they are always performed using a power-of-two value, enforcing this invariant through a dedicated type leads to fewer bugs and can improve the generated code. Introduce the `Alignment` type, inspired by the nightly Rust type of the same name and providing the same interface, and a new `Alignable` trait allowing unsigned integers to be aligned up or down. Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> [ Used `build_assert!`, added intra-doc link, `allow`ed `clippy::incompatible_msrv`, added `feature(const_option)`, capitalized safety comment. - Miguel ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-09-22Merge tag 'rust-timekeeping-v6.18' of ↵Miguel Ojeda6-10/+344
https://github.com/Rust-for-Linux/linux into rust-next Pull timekeeping updates from Andreas Hindborg: - Add methods on 'HrTimer' that can only be called with exclusive access to an unarmed timer, or form timer callback context. - Add arithmetic operations to 'Instant' and 'Delta'. - Add a few convenience and access methods to 'HrTimer' and 'Instant'. * tag 'rust-timekeeping-v6.18' of https://github.com/Rust-for-Linux/linux: rust: time: Implement basic arithmetic operations for Delta rust: time: Implement Add<Delta>/Sub<Delta> for Instant rust: hrtimer: Add HrTimer::expires() rust: time: Add Instant::from_ktime() rust: hrtimer: Add forward_now() to HrTimer and HrTimerCallbackContext rust: hrtimer: Add HrTimerCallbackContext and ::forward() rust: hrtimer: Add HrTimer::raw_forward() and forward() rust: hrtimer: Add HrTimerInstant rust: hrtimer: Document the return value for HrTimerHandle::cancel()
2025-09-22rust: add dynamic ID pool abstraction for bitmapBurak Emir2-0/+227
This is a port of the Binder data structure introduced in commit 15d9da3f818c ("binder: use bitmap for faster descriptor lookup") to Rust. Like drivers/android/dbitmap.h, the ID pool abstraction lets clients acquire and release IDs. The implementation uses a bitmap to know what IDs are in use, and gives clients fine-grained control over the time of allocation. This fine-grained control is needed in the Android Binder. We provide an example that release a spinlock for allocation and unit tests (rustdoc examples). The implementation does not permit shrinking below capacity below BITS_PER_LONG. Suggested-by: Alice Ryhl <aliceryhl@google.com> Suggested-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Burak Emir <bqe@google.com> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
2025-09-22rust: add find_bit_benchmark_rust module.Burak Emir2-0/+16
Microbenchmark protected by a config FIND_BIT_BENCHMARK_RUST, following `find_bit_benchmark.c` but testing the Rust Bitmap API. We add a fill_random() method protected by the config in order to maintain the abstraction. The sample output from the benchmark, both C and Rust version: find_bit_benchmark.c output: ``` Start testing find_bit() with random-filled bitmap [ 438.101937] find_next_bit: 860188 ns, 163419 iterations [ 438.109471] find_next_zero_bit: 912342 ns, 164262 iterations [ 438.116820] find_last_bit: 726003 ns, 163419 iterations [ 438.130509] find_nth_bit: 7056993 ns, 16269 iterations [ 438.139099] find_first_bit: 1963272 ns, 16270 iterations [ 438.173043] find_first_and_bit: 27314224 ns, 32654 iterations [ 438.180065] find_next_and_bit: 398752 ns, 73705 iterations [ 438.186689] Start testing find_bit() with sparse bitmap [ 438.193375] find_next_bit: 9675 ns, 656 iterations [ 438.201765] find_next_zero_bit: 1766136 ns, 327025 iterations [ 438.208429] find_last_bit: 9017 ns, 656 iterations [ 438.217816] find_nth_bit: 2749742 ns, 655 iterations [ 438.225168] find_first_bit: 721799 ns, 656 iterations [ 438.231797] find_first_and_bit: 2819 ns, 1 iterations [ 438.238441] find_next_and_bit: 3159 ns, 1 iterations ``` find_bit_benchmark_rust.rs output: ``` [ 451.182459] find_bit_benchmark_rust: [ 451.186688] Start testing find_bit() Rust with random-filled bitmap [ 451.194450] next_bit: 777950 ns, 163644 iterations [ 451.201997] next_zero_bit: 918889 ns, 164036 iterations [ 451.208642] Start testing find_bit() Rust with sparse bitmap [ 451.214300] next_bit: 9181 ns, 654 iterations [ 451.222806] next_zero_bit: 1855504 ns, 327026 iterations ``` Here are the results from 32 samples, with 95% confidence interval. The microbenchmark was built with RUST_BITMAP_HARDENED=n and run on a machine that did not execute other processes. Random-filled bitmap: +-----------+-------+-----------+--------------+-----------+-----------+ | Benchmark | Lang | Mean (ms) | Std Dev (ms) | 95% CI Lo | 95% CI Hi | +-----------+-------+-----------+--------------+-----------+-----------+ | find_bit/ | C | 825.07 | 53.89 | 806.40 | 843.74 | | next_bit | Rust | 870.91 | 46.29 | 854.88 | 886.95 | +-----------+-------+-----------+--------------+-----------+-----------+ | find_zero/| C | 933.56 | 56.34 | 914.04 | 953.08 | | next_zero | Rust | 945.85 | 60.44 | 924.91 | 966.79 | +-----------+-------+-----------+--------------+-----------+-----------+ Rust appears 5.5% slower for next_bit, 1.3% slower for next_zero. Sparse bitmap: +-----------+-------+-----------+--------------+-----------+-----------+ | Benchmark | Lang | Mean (ms) | Std Dev (ms) | 95% CI Lo | 95% CI Hi | +-----------+-------+-----------+--------------+-----------+-----------+ | find_bit/ | C | 13.17 | 6.21 | 11.01 | 15.32 | | next_bit | Rust | 14.30 | 8.27 | 11.43 | 17.17 | +-----------+-------+-----------+--------------+-----------+-----------+ | find_zero/| C | 1859.31 | 82.30 | 1830.80 | 1887.83 | | next_zero | Rust | 1908.09 | 139.82 | 1859.65 | 1956.54 | +-----------+-------+-----------+--------------+-----------+-----------+ Rust appears 8.5% slower for next_bit, 2.6% slower for next_zero. In summary, taking the arithmetic mean of all slow-downs, we can say the Rust API has a 4.5% slowdown. Suggested-by: Alice Ryhl <aliceryhl@google.com> Suggested-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> Reviewed-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Burak Emir <bqe@google.com> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
2025-09-22rust: add bitmap API.Burak Emir2-0/+586
Provides an abstraction for C bitmap API and bitops operations. This commit enables a Rust implementation of an Android Binder data structure from commit 15d9da3f818c ("binder: use bitmap for faster descriptor lookup"), which can be found in drivers/android/dbitmap.h. It is a step towards upstreaming the Rust port of Android Binder driver. We follow the C Bitmap API closely in naming and semantics, with a few differences that take advantage of Rust language facilities and idioms. The main types are `BitmapVec` for owned bitmaps and `Bitmap` for references to C bitmaps. * We leverage Rust type system guarantees as follows: * all (non-atomic) mutating operations require a &mut reference which amounts to exclusive access. * the `BitmapVec` type implements Send. This enables transferring ownership between threads and is needed for Binder. * the `BitmapVec` type implements Sync, which enables passing shared references &Bitmap between threads. Atomic operations can be used to safely modify from multiple threads (interior mutability), though without ordering guarantees. * The Rust API uses `{set,clear}_bit` vs `{set,clear}_bit_atomic` as names for clarity, which differs from the C naming convention `set_bit` for atomic vs `__set_bit` for non-atomic. * we include enough operations for the API to be useful. Not all operations are exposed yet in order to avoid dead code. The missing ones can be added later. * We take a fine-grained approach to safety: * Low-level bit-ops get a safe API with bounds checks. Calling with an out-of-bounds arguments to {set,clear}_bit becomes a no-op and get logged as errors. * We also introduce a RUST_BITMAP_HARDENED config, which causes invocations with out-of-bounds arguments to panic. * methods correspond to find_* C methods tolerate out-of-bounds since the C implementation does. Also here, out-of-bounds arguments are logged as errors, or panic in RUST_BITMAP_HARDENED mode. * We add a way to "borrow" bitmaps from C in Rust, to make C bitmaps that were allocated in C directly usable in Rust code (`Bitmap`). * the Rust API is optimized to represent the bitmap inline if it would fit into a pointer. This saves allocations which is relevant in the Binder use case. The underlying C bitmap is *not* exposed for raw access in Rust. Doing so would permit bypassing the Rust API and lose static guarantees. An alternative route of vendoring an existing Rust bitmap package was considered but suboptimal overall. Reusing the C implementation is preferable for a basic data structure like bitmaps. It enables Rust code to be a lot more similar and predictable with respect to C code that uses the same data structures and enables the use of code that has been tried-and-tested in the kernel, with the same performance characteristics whenever possible. We use the `usize` type for sizes and indices into the bitmap, because Rust generally always uses that type for indices and lengths and it will be more convenient if the API accepts that type. This means that we need to perform some casts to/from u32 and usize, since the C headers use unsigned int instead of size_t/unsigned long for these numbers in some places. Adds new MAINTAINERS section BITMAP API [RUST]. Suggested-by: Alice Ryhl <aliceryhl@google.com> Suggested-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Burak Emir <bqe@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
2025-09-22rust: add bindings for bitops.hBurak Emir2-0/+24
Makes atomic set_bit and clear_bit inline functions as well as the non-atomic variants __set_bit and __clear_bit available to Rust. Adds a new MAINTAINERS section BITOPS API BINDINGS [RUST]. Suggested-by: Alice Ryhl <aliceryhl@google.com> Suggested-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Burak Emir <bqe@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
2025-09-22rust: add bindings for bitmap.hBurak Emir3-0/+11
Makes the bitmap_copy_and_extend inline function available to Rust. Adds F: to existing MAINTAINERS section BITMAP API BINDINGS [RUST]. - Suggested-by: Alice Ryhl <aliceryhl@google.com> Suggested-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Burak Emir <bqe@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Yury Norov (NVIDIA) <yury.norov@gmail.com> Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
2025-09-22rust: macros: reduce collections in `quote!` macroTamir Duberstein1-55/+49
Remove a handful of unnecessary intermediate vectors and token streams; mainly the top-level stream can be directly extended with the notable exception of groups. Remove an unnecessary `#[allow(dead_code)]` added in commit dbd5058ba60c ("rust: make pin-init its own crate"). Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Acked-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Tamir Duberstein <tamird@gmail.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2025-09-21rust: maple_tree: add MapleTreeAllocAlice Ryhl1-0/+158
To support allocation trees, we introduce a new type MapleTreeAlloc for the case where the tree is created using MT_FLAGS_ALLOC_RANGE. To ensure that you can only call mtree_alloc_range on an allocation tree, we restrict thta method to the new MapleTreeAlloc type. However, all methods on MapleTree remain accessible to MapleTreeAlloc as allocation trees can use the other methods without issues. Link: https://lkml.kernel.org/r/20250902-maple-tree-v3-3-fb5c8958fb1e@google.com Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Cc: Andreas Hindborg <a.hindborg@kernel.org> Cc: Andrew Ballance <andrewjballance@gmail.com> Cc: Björn Roy Baron <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Gary Guo <gary@garyguo.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Trevor Gross <tmgross@umich.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-21rust: maple_tree: add lock guard for maple treeAlice Ryhl1-0/+140
To load a value, one must be careful to hold the lock while accessing it. To enable this, we add a lock() method so that you can perform operations on the value before the spinlock is released. This adds a MapleGuard type without using the existing SpinLock type. This ensures that the MapleGuard type is not unnecessarily large, and that it is easy to swap out the type of lock in case the C maple tree is changed to use a different kind of lock. There are two ways of using the lock guard: You can call load() directly to load a value under the lock, or you can create an MaState to iterate the tree with find(). The find() method does not have the mas_ prefix since it's a method on MaState, and being a method on that struct serves a similar purpose to the mas_ prefix in C. Link: https://lkml.kernel.org/r/20250902-maple-tree-v3-2-fb5c8958fb1e@google.com Co-developed-by: Andrew Ballance <andrewjballance@gmail.com> Signed-off-by: Andrew Ballance <andrewjballance@gmail.com> Reviewed-by: Andrew Ballance <andrewjballance@gmail.com> Reviewed-by: Danilo Krummrich <dakr@kernel.org> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Cc: Andreas Hindborg <a.hindborg@kernel.org> Cc: Björn Roy Baron <bjorn3_gh@protonmail.com> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Daniel Almeida <daniel.almeida@collabora.com> Cc: Gary Guo <gary@garyguo.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Trevor Gross <tmgross@umich.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-21rust: maple_tree: add MapleTreeAlice Ryhl4-0/+359
Patch series "Add Rust abstraction for Maple Trees", v3. This will be used in the Tyr driver [1] to allocate from the GPU's VA space that is not owned by userspace, but by the kernel, for kernel GPU mappings. Danilo tells me that in nouveau, the maple tree is used for keeping track of "VM regions" on top of GPUVM, and that he will most likely end up doing the same in the Rust Nova driver as well. These abstractions intentionally do not expose any way to make use of external locking. You ar