linux/rust/kernel/lib.rs, branch v6.17

rust: use the new name Location::file_as_c_str() in Rust >= 1.91.0

2025-08-31T21:34:34Z

As part of the stabilization of Location::file_with_nul(), it was brought up that the with_nul() suffix usually means something else in Rust APIs, so the API is being renamed prior to stabilization [1]. Thus, use the new name on new rustc versions. Link: https://www.github.com/rust-lang/rust/pull/145928 [1] Signed-off-by: Alice Ryhl Reviewed-by: Boqun Feng Link: https://lore.kernel.org/r/20250827-file_as_c_str-v1-1-d3f5a3916a9c@google.com [ Kept `cfg` separation. Reworded slightly. - Miguel ] Signed-off-by: Miguel Ojeda

Merge tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

2025-08-03T20:49:10Z

Pull Rust updates from Miguel Ojeda: "Toolchain and infrastructure: - Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness', 'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and 'ref_as_ptr' These are intended to avoid type casts with the 'as' operator, which are quite powerful, into restricted variants that are less powerful and thus should help to avoid mistakes - Remove the 'author' key now that most instances were moved to the plural one in the previous cycle 'kernel' crate: - New 'bug' module: add 'warn_on!' macro which reuses the existing 'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and kernel parameters: warn_on!(value == 42); To avoid duplicating the assembly code, the same strategy is followed as for the static branch code in order to share the assembly between both C and Rust This required a few rearrangements on C arch headers -- the existing C macros should still generate the same outputs, thus no functional change expected there - 'workqueue' module: add delayed work items, including a 'DelayedWork' struct, a 'impl_has_delayed_work!' macro and an 'enqueue_delayed' method, e.g.: /// Enqueue the struct for execution on the system workqueue, /// where its value will be printed 42 jiffies later. fn print_later(value: Arc) { let _ = workqueue::system().enqueue_delayed(value, 42); } - New 'bits' module: add support for 'bit' and 'genmask' functions, with runtime- and compile-time variants, e.g.: static_assert!(0b00010000 == bit_u8(4)); static_assert!(0b00011110 == genmask_u8(1..=4)); assert!(checked_bit_u32(u32::BITS).is_none()); - 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which reads NUL-terminated strings from userspace into a '&CStr' Introduce 'UserPtr' newtype, similar in purpose to '__user' in C, to minimize mistakes handling userspace pointers, including mixing them up with integers and leaking them via the 'Debug' trait. Add it to the prelude, too - Start preparations for the replacement of our custom 'CStr' type with the analogous type in the 'core' standard library. This will take place across several cycles to make it easier. For this one, it includes a new 'fmt' module, using upstream method names and some other cleanups Replace 'fmt!' with a re-export, which helps Clippy lint properly, and clean up the found 'uninlined-format-args' instances - 'dma' module: - Clarify wording and be consistent in 'coherent' nomenclature - Convert the 'read!()' and 'write!()' macros to return a 'Result' - Add 'as_slice()', 'write()' methods in 'CoherentAllocation' - Expose 'count()' and 'size()' in 'CoherentAllocation' and add the corresponding type invariants - Implement 'CoherentAllocation::dma_handle_with_offset()' - 'time' module: - Make 'Instant' generic over clock source. This allows the compiler to assert that arithmetic expressions involving the 'Instant' use 'Instants' based on the same clock source - Make 'HrTimer' generic over the timer mode. 'HrTimer' timers take a 'Duration' or an 'Instant' when setting the expiry time, depending on the timer mode. With this change, the compiler can check the type matches the timer mode - Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep function that will select an appropriate sleep method depending on the requested sleep time - Avoid 64-bit divisions on 32-bit hardware when calculating timestamps - Seal the 'HrTimerMode' trait. This prevents users of the 'HrTimerMode' from implementing the trait on their own types - Pass the correct timer mode ID to 'hrtimer_start_range_ns()' - 'list' module: remove 'OFFSET' constants, allowing to remove pointer arithmetic; now 'impl_list_item!' invokes 'impl_has_list_links!' or 'impl_has_list_links_self_ptr!'. Other simplifications too - 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a constant, which avoids exposing the type of the opaque pointer, and require 'into_foreign' to return non-null Remove the 'Either' type as well. It is unused, and we want to encourage the use of custom enums for concrete use cases - 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types to allow them to be used in generic APIs - 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box'; and 'Borrow', 'BorrowMut' and 'Default' for 'Vec' - 'Opaque' type: add 'cast_from' method to perform a restricted cast that cannot change the inner type and use it in callers of 'container_of!'. Rename 'raw_get' to 'cast_into' to match it - 'rbtree' module: add 'is_empty' method - 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and 'ARef', which are moved from the too general 'types' module which we want to reduce or eventually remove. Also fix a safety comment in 'static_lock_class' 'pin-init' crate: - Add 'impl [Pin]Init for Result', so results are now (pin-)initializers - Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()' - New 'zeroed()', a safe version of 'mem::zeroed()' and also provide it via 'Zeroable::zeroed()' - Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for 'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for '"Rust"' and '"C"' ABIs and up to 20 arguments - Changed blanket impls of 'Init' and 'PinInit' from 'impl [Pin]Init for T' to 'impl [Pin]Init for T' - Renamed 'zeroed()' to 'init_zeroed()' - Upstream dev news: improve CI more to deny warnings, use '--all-targets'. Check the synchronization status of the two '-next' branches in upstream and the kernel MAINTAINERS: - Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo Stoakes as reviewers (thanks everyone) And a few other cleanups and improvements" * tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (76 commits) rust: Add warn_on macro arm64/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust riscv/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust x86/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust rust: kernel: move ARef and AlwaysRefCounted to sync::aref rust: sync: fix safety comment for `static_lock_class` rust: types: remove `Either` rust: kernel: use `core::ffi::CStr` method names rust: str: add `CStr` methods matching `core::ffi::CStr` rust: str: remove unnecessary qualification rust: use `kernel::{fmt,prelude::fmt!}` rust: kernel: add `fmt` module rust: kernel: remove `fmt!`, fix clippy::uninlined-format-args scripts: rust: emit path candidates in panic message scripts: rust: replace length checks with match rust: list: remove nonexistent generic parameter in link rust: bits: add support for bits/genmask macros rust: list: remove OFFSET constants rust: list: add `impl_list_item!` examples rust: list: use fully qualified path ...

Merge tag 'sched-core-2025-07-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-07-30T00:42:52Z

Pull scheduler updates from Ingo Molnar: "Core scheduler changes: - Better tracking of maximum lag of tasks in presence of different slices duration, for better handling of lag in the fair scheduler (Vincent Guittot) - Clean up and standardize #if/#else/#endif markers throughout the entire scheduler code base (Ingo Molnar) - Make SMP unconditional: build the SMP scheduler's data structures and logic on UP kernel too, even though they are not used, to simplify the scheduler and remove around 200 #ifdef/[#else]/#endif blocks from the scheduler (Ingo Molnar) - Reorganize cgroup bandwidth control interface handling for better interfacing with sched_ext (Tejun Heo) Balancing: - Bump sd->max_newidle_lb_cost when newidle balance fails (Chris Mason) - Remove sched_domain_topology_level::flags to simplify the code (Prateek Nayak) - Simplify and clean up build_sched_topology() (Li Chen) - Optimize build_sched_topology() on large machines (Li Chen) Real-time scheduling: - Add initial version of proxy execution: a mechanism for mutex-owning tasks to inherit the scheduling context of higher priority waiters. Currently limited to a single runqueue and conditional on CONFIG_EXPERT, and other limitations (John Stultz, Peter Zijlstra, Valentin Schneider) - Deadline scheduler (Juri Lelli): - Fix dl_servers initialization order (Juri Lelli) - Fix DL scheduler's root domain reinitialization logic (Juri Lelli) - Fix accounting bugs after global limits change (Juri Lelli) - Fix scalability regression by implementing less agressive dl_server handling (Peter Zijlstra) PSI: - Improve scalability by optimizing psi_group_change() cpu_clock() usage (Peter Zijlstra) Rust changes: - Make Task, CondVar and PollCondVar methods inline to avoid unnecessary function calls (Kunwu Chan, Panagiotis Foliadis) - Add might_sleep() support for Rust code: Rust's "#[track_caller]" mechanism is used so that Rust's might_sleep() doesn't need to be defined as a macro (Fujita Tomonori) - Introduce file_from_location() (Boqun Feng) Debugging & instrumentation: - Make clangd usable with scheduler source code files again (Peter Zijlstra) - tools: Add root_domains_dump.py which dumps root domains info (Juri Lelli) - tools: Add dl_bw_dump.py for printing bandwidth accounting info (Juri Lelli) Misc cleanups & fixes: - Remove play_idle() (Feng Lee) - Fix check_preemption_disabled() (Sebastian Andrzej Siewior) - Do not call __put_task_struct() on RT if pi_blocked_on is set (Luis Claudio R. Goncalves) - Correct the comment in place_entity() (wang wei)" * tag 'sched-core-2025-07-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (84 commits) sched/idle: Remove play_idle() sched: Do not call __put_task_struct() on rt if pi_blocked_on is set sched: Start blocked_on chain processing in find_proxy_task() sched: Fix proxy/current (push,pull)ability sched: Add an initial sketch of the find_proxy_task() function sched: Fix runtime accounting w/ split exec & sched contexts sched: Move update_curr_task logic into update_curr_se locking/mutex: Add p->blocked_on wrappers for correctness checks locking/mutex: Rework task_struct::blocked_on sched: Add CONFIG_SCHED_PROXY_EXEC & boot argument to enable/disable sched/topology: Remove sched_domain_topology_level::flags x86/smpboot: avoid SMT domain attach/destroy if SMT is not enabled x86/smpboot: moves x86_topology to static initialize and truncate x86/smpboot: remove redundant CONFIG_SCHED_SMT smpboot: introduce SDTL_INIT() helper to tidy sched topology setup tools/sched: Add dl_bw_dump.py for printing bandwidth accounting info tools/sched: Add root_domains_dump.py which dumps root domains info sched/deadline: Fix accounting after global limits change sched/deadline: Reset extra_bw to max_bw when clearing root domains sched/deadline: Initialize dl_servers after SMP ...

Merge tag 'driver-core-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

2025-07-29T19:15:39Z

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 - 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 for Opaque - 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 ...

Merge tag 'regulator-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator

2025-07-29T05:52:02Z

Pull regulator updates from Mark Brown: "The big change in this release is the addition of Rust bindings from Daniel Almeida, allowing fairly basic consumer use with support for enable and voltage setting operations. This should be good for the vast majority of consumers. Otherwise it's been quite quiet, a few new devices supported, plus some cleanups and fixes. Summary: - Basic Rust bindings - A fix for making large voltage changes on regulators where we limit the size of voltage change we will do in one step, previously we just got as close as we could in one step - Cleanups of our usage of the PM autosuspend functions, this pulls in some PM core changes on a shared tag - Mode setting support for PCA9450 - Support for Mediatek MT6893 and MT8196 DVFSRC, Qualcomm PM7550 and PMR735B, Raspberry Pi displays and TI TPS652G1 The TI driver pulls in the MFD portion of the support for the device and the pinctrl driver which was in the same tag" * tag 'regulator-v6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator: (40 commits) regulator: mt6370: Fix spelling mistake in mt6370_regualtor_register regulator: Kconfig: Fix spelling mistake "regualtor" -> "regulator" regulator: core: repeat voltage setting request for stepped regulators regulator: rt6160: Add rt6166 vout min_uV setting for compatible MAINTAINERS: add regulator.rs to the regulator API entry rust: regulator: add a bare minimum regulator abstraction regulator: tps6286x-regulator: Fix a copy & paste error regulator: qcom-rpmh: add support for pm7550 regulators regulator: qcom-rpmh: add support for pmr735b regulators regulator: dt-bindings: qcom,rpmh: Add PMR735B compatible regulator: dt-bindings: qcom,rpmh: Add PM7550 compatible regulator: tps6594-regulator: Add TI TPS652G1 PMIC regulators regulator: tps6594-regulator: refactor variant descriptions regulator: tps6594-regulator: remove hardcoded buck config regulator: tps6594-regulator: remove interrupt_count dt-bindings: mfd: ti,tps6594: Add TI TPS652G1 PMIC pinctrl: pinctrl-tps6594: Add TPS652G1 PMIC pinctrl and GPIO misc: tps6594-pfsm: Add TI TPS652G1 PMIC PFSM mfd: tps6594: Add TI TPS652G1 support regulator: sy8827n: make enable gpio NONEXCLUSIVE ...

rust: Add warn_on macro

2025-07-23T00:05:58Z

Add warn_on macro, uses the BUG/WARN feature (lib/bug.c) via assembly for x86_64/arm64/riscv. The current Rust code simply wraps BUG() macro but doesn't provide the proper debug information. The BUG/WARN feature can only be used from assembly. This uses the assembly code exported by the C side via ARCH_WARN_ASM macro. To avoid duplicating the assembly code, this approach follows the same strategy as the static branch code: it generates the assembly code for Rust using the C preprocessor at compile time. Similarly, ARCH_WARN_REACHABLE is also used at compile time to generate the assembly code; objtool's reachable annotation code. It's used for only architectures that use objtool. For now, Loongarch and arm just use a wrapper for WARN macro. UML doesn't use the assembly BUG/WARN feature; just wrapping generic BUG/WARN functions implemented in C works. Signed-off-by: FUJITA Tomonori Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250502094537.231725-5-fujita.tomonori@gmail.com [ Avoid evaluating the condition twice (a good idea in general, but it also matches the C side). Simplify with `as_char_ptr()` to avoid a cast. Cast to `ffi` integer types for `warn_slowpath_fmt`. Avoid cast for `null()`. - Miguel ] Signed-off-by: Miguel Ojeda

rust: kernel: add `fmt` module

2025-07-20T23:16:35Z

`kernel::fmt` is a facade over `core::fmt` that can be used downstream, allowing future changes to the formatting machinery to be contained within the kernel crate without downstream code needing to be modified. Signed-off-by: Tamir Duberstein Reviewed-by: Benno Lossin Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250704-core-cstr-prepare-v1-2-a91524037783@gmail.com Signed-off-by: Miguel Ojeda

rust: bits: add support for bits/genmask macros

2025-07-19T21:18:18Z

In light of bindgen being unable to generate bindings for macros, and owing to the widespread use of these macros in drivers, manually define the bit and genmask C macros in Rust. The *_checked version of the functions provide runtime checking while the const version performs compile-time assertions on the arguments via the build_assert!() macro. Reviewed-by: Alice Ryhl Reviewed-by: Alexandre Courbot Signed-off-by: Daniel Almeida Reviewed-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250714-topics-tyr-genmask2-v9-1-9e6422cbadb6@collabora.com [ `expect`ed Clippy warning in doctests, hid single `use`, grouped examples. Reworded title. - Miguel ] Signed-off-by: Miguel Ojeda

rust: types: rename Opaque::raw_get to cast_into

2025-07-15T20:26:11Z

In the previous patch we added Opaque::cast_from() that performs the opposite operation to Opaque::raw_get(). For consistency with this naming, rename raw_get() to cast_from(). There are a few other options such as calling cast_from() something closer to raw_get() rather than renaming this method. However, I could not find a great naming scheme that works with raw_get(). The previous version of this patch used from_raw(), but functions of that name typically have a different signature, so that's not a great option. Suggested-by: Danilo Krummrich Signed-off-by: Alice Ryhl Acked-by: Benno Lossin Acked-by: Andreas Hindborg Acked-by: Boqun Feng Reviewed-by: Danilo Krummrich Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250624-opaque-from-raw-v2-2-e4da40bdc59c@google.com [ Removed `HrTimer::raw_get` change. - Miguel ] Signed-off-by: Miguel Ojeda

rust: types: add Opaque::cast_from

2025-07-15T19:01:48Z

Since commit b20fbbc08a36 ("rust: check type of `$ptr` in `container_of!`") we have enforced that the field pointer passed to container_of! must match the declared field. This caused mismatches when using a pointer to bindings::x for fields of type Opaque. This situation encourages the user to simply pass field.cast() to the container_of! macro, but this is not great because you might accidentally pass a *mut bindings::y when the field type is Opaque, which would be wrong. To help catch this kind of mistake, add a new Opaque::cast_from that wraps a raw pointer in Opaque without changing the inner type. Also update the docs to reflect this as well as some existing users. Signed-off-by: Alice Ryhl Acked-by: Andreas Hindborg Acked-by: Boqun Feng Reviewed-by: Danilo Krummrich Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250624-opaque-from-raw-v2-1-e4da40bdc59c@google.com Signed-off-by: Miguel Ojeda