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2024-01-11Merge tag 'rust-6.8' of https://github.com/Rust-for-Linux/linuxLinus Torvalds
Pull Rust updates from Miguel Ojeda: "Another routine one in terms of features. In terms of lines, this time the 'alloc' version upgrade is less prominent, given that it was fairly small (and we did not have two upgrades) Toolchain and infrastructure: - Upgrade to Rust 1.74.1 The patch release includes a fix for an ICE that the Apple AGX GPU driver was hitting - Support 'srctree'-relative links in Rust code documentation - Automate part of the manual constants handling (i.e. the ones not recognised by 'bindgen') - Suppress searching builtin sysroot to avoid confusion with installed sysroots, needed for the to-be-merged arm64 support which uses a builtin target - Ignore '__preserve_most' functions for 'bindgen' - Reduce header inclusion bloat in exports 'kernel' crate: - Implement 'Debug' for 'CString' - Make 'CondVar::wait()' an uninterruptible wait 'macros' crate: - Update 'paste!' to accept string literals - Improve '#[vtable]' documentation Documentation: - Add testing section (KUnit and 'rusttest' target) - Remove 'CC=clang' mentions - Clarify that 'rustup override' applies to build directory" * tag 'rust-6.8' of https://github.com/Rust-for-Linux/linux: docs: rust: Clarify that 'rustup override' applies to build directory docs: rust: Add rusttest info docs: rust: remove `CC=clang` mentions rust: support `srctree`-relative links rust: sync: Makes `CondVar::wait()` an uninterruptible wait rust: upgrade to Rust 1.74.1 rust: Suppress searching builtin sysroot rust: macros: improve `#[vtable]` documentation rust: macros: update 'paste!' macro to accept string literals rust: bindings: rename const binding using sed rust: Ignore preserve-most functions rust: replace <linux/module.h> with <linux/export.h> in rust/exports.c rust: kernel: str: Implement Debug for CString
2023-12-21rust: support `srctree`-relative linksMiguel Ojeda
Some of our links use relative paths in order to point to files in the source tree, e.g.: //! C header: [`include/linux/printk.h`](../../../../include/linux/printk.h) /// [`struct mutex`]: ../../../../include/linux/mutex.h These are problematic because they are hard to maintain and do not support `O=` builds. Instead, provide support for `srctree`-relative links, e.g.: //! C header: [`include/linux/printk.h`](srctree/include/linux/printk.h) /// [`struct mutex`]: srctree/include/linux/mutex.h The links are fixed after `rustdoc` generation to be based on the absolute path to the source tree. Essentially, this is the automatic version of Tomonori's fix [1], suggested by Gary [2]. Suggested-by: Gary Guo <gary@garyguo.net> Reported-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Closes: https://lore.kernel.org/r/20231026.204058.2167744626131849993.fujita.tomonori@gmail.com [1] Fixes: 48fadf440075 ("docs: Move rustdoc output, cross-reference it") Link: https://lore.kernel.org/rust-for-linux/20231026154525.6d14b495@eugeo/ [2] Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20231215235428.243211-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-21rust: sync: Makes `CondVar::wait()` an uninterruptible waitBoqun Feng
Currently, `CondVar::wait()` is an interruptible wait, and this is different than `wait_event()` in include/linux/wait.h (which is an uninterruptible wait). To avoid confusion between different APIs on the interruptible/uninterruptible, make `CondVar::wait()` an uninterruptible wait same as `wait_event()`, also rename the old `wait()` to `CondVar::wait_interruptible()`. Spotted-by: Tiago Lam <tiagolam@gmail.com> Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Tiago Lam <tiagolam@gmail.com> Link: https://lore.kernel.org/r/20231214200421.690629-1-boqun.feng@gmail.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-21rust: upgrade to Rust 1.74.1Miguel Ojeda
This is the next upgrade to the Rust toolchain, from 1.73.0 to 1.74.1 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4da06e ("rust: upgrade to Rust 1.68.2"). # Unstable features No unstable features (that we use) were stabilized. Therefore, the only unstable features allowed to be used outside the `kernel` crate are still `new_uninit,offset_of`, though other code to be upstreamed may increase the list (e.g. `offset_of` was added recently). Please see [3] for details. # Other improvements Rust 1.74.0 allows to use `#[repr(Rust)]` explicitly [4], which can be useful to be explicit about particular cases that would normally use e.g. the C representation, such as silencing lints like the upcoming additions we requested [5] to the `no_mangle_with_rust_abi` Clippy lint (which in turn triggered the `#[repr(Rust)]` addition). Rust 1.74.0 includes a fix for one of the false negative cases we reported in Clippy's `disallowed_macros` lint [6] that we would like to use in the future. Rust 1.74.1 fixes an ICE that the Apple AGX GPU driver was hitting [7]. # Required changes For this upgrade, no changes were required (i.e. on our side). # `alloc` upgrade and reviewing The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1741-2023-12-07 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: https://github.com/Rust-for-Linux/linux/issues/2 [3] Link: https://github.com/rust-lang/rust/pull/114201 [4] Link: https://github.com/rust-lang/rust-clippy/issues/11219 [5] Link: https://github.com/rust-lang/rust-clippy/issues/11431 [6] Link: https://github.com/rust-lang/rust/issues/117976#issuecomment-1822225691 [7] Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Tested-by: David Gow <davidgow@google.com> Link: https://lore.kernel.org/r/20231214092958.377061-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-15net: phy: add Rust Asix PHY driverFUJITA Tomonori
This is the Rust implementation of drivers/net/phy/ax88796b.c. The features are equivalent. You can choose C or Rust version kernel configuration. Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Trevor Gross <tmgross@umich.edu> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-15rust: net::phy add module_phy_driver macroFUJITA Tomonori
This macro creates an array of kernel's `struct phy_driver` and registers it. This also corresponds to the kernel's `MODULE_DEVICE_TABLE` macro, which embeds the information for module loading into the module binary file. A PHY driver should use this macro. Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Trevor Gross <tmgross@umich.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-15rust: core abstractions for network PHY driversFUJITA Tomonori
This patch adds abstractions to implement network PHY drivers; the driver registration and bindings for some of callback functions in struct phy_driver and many genphy_ functions. This feature is enabled with CONFIG_RUST_PHYLIB_ABSTRACTIONS=y. This patch enables unstable const_maybe_uninit_zeroed feature for kernel crate to enable unsafe code to handle a constant value with uninitialized data. With the feature, the abstractions can initialize a phy_driver structure with zero easily; instead of initializing all the members by hand. It's supposed to be stable in the not so distant future. Link: https://github.com/rust-lang/rust/pull/116218 Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-14rust: Suppress searching builtin sysrootMatthew Maurer
By default, if Rust is passed `--target=foo` rather than a target.json file, it will infer a default sysroot if that component is installed. As the proposed aarch64 support [1] uses `aarch64-unknown-none` rather than a target.json file, this is needed [2] to prevent rustc from being confused between the custom kernel sysroot and the pre-installed one. [ Miguel: Applied Boqun's extra case (for `rusttest`) and reworded to add links to the arm64 patch series discussion. In addition, fixed the `rustdoc` target too (which requires a conditional since `cmd_rustdoc` is also used for host crates like `macros`). ] Signed-off-by: Matthew Maurer <mmaurer@google.com> Tested-by: Boqun Feng <boqun.feng@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/rust-for-linux/20231020155056.3495121-1-Jamie.Cunliffe@arm.com/ [1] Link: https://lore.kernel.org/rust-for-linux/CAGSQo01pOixiPXkW867h4vPUaAjtKtHGKhkV-rpifJvKxAf4Ww@mail.gmail.com/ [2] Link: https://lore.kernel.org/r/20231031201752.1189213-1-mmaurer@google.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-14rust: macros: improve `#[vtable]` documentationBenno Lossin
Traits marked with `#[vtable]` need to provide default implementations for optional functions. The C side represents these with `NULL` in the vtable, so the default functions are never actually called. We do not want to replicate the default behavior from C in Rust, because that is not maintainable. Therefore we should use `build_error` in those default implementations. The error message for that is provided at `kernel::error::VTABLE_DEFAULT_ERROR`. Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Finn Behrens <me@kloenk.dev> Link: https://lore.kernel.org/r/20231026201855.1497680-1-benno.lossin@proton.me [ Wrapped paragraph to 80 as requested and capitalized sentence. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-14rust: macros: update 'paste!' macro to accept string literalsTrevor Gross
Enable combining identifiers with literals in the 'paste!' macro. This allows combining user-specified strings with affixes to create namespaced identifiers. This sample code: macro_rules! m { ($name:lit) => { paste!(struct [<_some_ $name _struct_>] {}) } } m!("foo_bar"); Would previously cause a compilation error. It will now generate: struct _some_foo_bar_struct_ {} Signed-off-by: Trevor Gross <tmgross@umich.edu> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://lore.kernel.org/r/20231118013959.37384-1-tmgross@umich.edu [ Added `:` before example block. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-14rust: bindings: rename const binding using sedGary Guo
Currently, for `const`s that bindgen doesn't recognise, we define a helper constant with const <TYPE> BINDINGS_<NAME> = <NAME>; in `bindings_helper.h` and then we put pub const <NAME>: <TYPE> = BINDINGS_<NAME>; in `bindings/lib.rs`. This is fine since we currently only have 3 constants that are defined this way, but is going to be more annoying when more constants are added since every new constant needs to be defined in two places. This patch changes the way we define constant helpers to const <TYPE> RUST_CONST_HELPER_<NAME> = <NAME>; and then use `sed` to postprocess Rust code generated by bindgen to remove the distinct prefix, so users of the `bindings` crate can refer to the name directly. Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Signed-off-by: Gary Guo <gary@garyguo.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20231104145700.2495176-1-gary@garyguo.net [ Reworded for typos. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-13rust: Ignore preserve-most functionsMatthew Maurer
Neither bindgen nor Rust know about the preserve-most calling convention, and Clang describes it as unstable. Since we aren't using functions with this calling convention from Rust, blocklist them. These functions are only added to the build when list hardening is enabled, which is likely why others didn't notice this yet. Signed-off-by: Matthew Maurer <mmaurer@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20231031201945.1412345-1-mmaurer@google.com [ Used Markdown for consistency with the other comments in the file. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-13rust: replace <linux/module.h> with <linux/export.h> in rust/exports.cMasahiro Yamada
<linux/export.h> is the right header to include for using EXPORT_SYMBOL_GPL. <linux/module.h> includes much more bloat. Signed-off-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20231124142617.713096-1-masahiroy@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-12-13rust: kernel: str: Implement Debug for CStringAsahi Lina
Make it possible to use a `CString` with the `pr_*` macros directly. That is, instead of: pr_debug!("trying to open {:?}\n", &*filename); we can now write: pr_debug!("trying to open {:?}\n", filename); Signed-off-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20230714-cstring-debug-v1-1-4e7c3018dd4f@asahilina.net [ Reworded to use Alice's commit message as discussed. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-11-04Merge tag 'kbuild-v6.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull Kbuild updates from Masahiro Yamada: - Implement the binary search in modpost for faster symbol lookup - Respect HOSTCC when linking host programs written in Rust - Change the binrpm-pkg target to generate kernel-devel RPM package - Fix endianness issues for tee and ishtp MODULE_DEVICE_TABLE - Unify vdso_install rules - Remove unused __memexit* annotations - Eliminate stale whitelisting for __devinit/__devexit from modpost - Enable dummy-tools to handle the -fpatchable-function-entry flag - Add 'userldlibs' syntax * tag 'kbuild-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (30 commits) kbuild: support 'userldlibs' syntax kbuild: dummy-tools: pretend we understand -fpatchable-function-entry kbuild: Correct missing architecture-specific hyphens modpost: squash ALL_{INIT,EXIT}_TEXT_SECTIONS to ALL_TEXT_SECTIONS modpost: merge sectioncheck table entries regarding init/exit sections modpost: use ALL_INIT_SECTIONS for the section check from DATA_SECTIONS modpost: disallow the combination of EXPORT_SYMBOL and __meminit* modpost: remove EXIT_SECTIONS macro modpost: remove MEM_INIT_SECTIONS macro modpost: remove more symbol patterns from the section check whitelist modpost: disallow *driver to reference .meminit* sections linux/init: remove __memexit* annotations modpost: remove ALL_EXIT_DATA_SECTIONS macro kbuild: simplify cmd_ld_multi_m kbuild: avoid too many execution of scripts/pahole-flags.sh kbuild: remove ARCH_POSTLINK from module builds kbuild: unify no-compiler-targets and no-sync-config-targets kbuild: unify vdso_install rules docs: kbuild: add INSTALL_DTBS_PATH UML: remove unused cmd_vdso_install ...
2023-10-30Merge tag 'wq-for-6.7-rust-bindings' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq Pull workqueue rust bindings from Tejun Heo: "Add rust bindings to allow rust code to schedule work items on workqueues. While the current bindings don't cover all of the workqueue API, it provides enough for basic usage and can be expanded as needed" * tag 'wq-for-6.7-rust-bindings' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: rust: workqueue: add examples rust: workqueue: add `try_spawn` helper method rust: workqueue: implement `WorkItemPointer` for pointer types rust: workqueue: add helper for defining work_struct fields rust: workqueue: define built-in queues rust: workqueue: add low-level workqueue bindings rust: sync: add `Arc::{from_raw, into_raw}`
2023-10-30Merge tag 'rust-6.7' of https://github.com/Rust-for-Linux/linuxLinus Torvalds
Pull rust updates from Miguel Ojeda: "A small one compared to the previous one in terms of features. In terms of lines, as usual, the 'alloc' version upgrade accounts for most of them. Toolchain and infrastructure: - Upgrade to Rust 1.73.0 This time around, due to how the kernel and Rust schedules have aligned, there are two upgrades in fact. They contain the fixes for a few issues we reported to the Rust project. In addition, a few cleanups indicated by the upgraded compiler or possible thanks to it. For instance, the compiler now detects redundant explicit links. - A couple changes to the Rust 'Makefile' so that it can be used with toybox tools, allowing Rust to be used in the Android kernel build. x86: - Enable IBT if enabled in C Documentation: - Add "The Rust experiment" section to the Rust index page MAINTAINERS: - Add Maintainer Entry Profile field ('P:'). - Update our 'W:' field to point to the webpage we have been building this year" * tag 'rust-6.7' of https://github.com/Rust-for-Linux/linux: docs: rust: add "The Rust experiment" section x86: Enable IBT in Rust if enabled in C rust: Use grep -Ev rather than relying on GNU grep rust: Use awk instead of recent xargs rust: upgrade to Rust 1.73.0 rust: print: use explicit link in documentation rust: task: remove redundant explicit link rust: kernel: remove `#[allow(clippy::new_ret_no_self)]` MAINTAINERS: add Maintainer Entry Profile field for Rust MAINTAINERS: update Rust webpage rust: upgrade to Rust 1.72.1 rust: arc: add explicit `drop()` around `Box::from_raw()`
2023-10-19rust: docs: fix logo replacementMiguel Ojeda
The static files placement by `rustdoc` changed in Rust 1.67.0 [1], but the custom code we have to replace the logo in the generated HTML files did not get updated. Thus update it to have the Linux logo again in the output. Hopefully `rustdoc` will eventually support a custom logo from a local file [2], so that we do not need to maintain this hack on our side. Link: https://github.com/rust-lang/rust/pull/101702 [1] Link: https://github.com/rust-lang/rfcs/pull/3226 [2] Fixes: 3ed03f4da06e ("rust: upgrade to Rust 1.68.2") Cc: stable@vger.kernel.org Tested-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Link: https://lore.kernel.org/r/20231018155527.1015059-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-15rust: Use grep -Ev rather than relying on GNU grepMatthew Maurer
While GNU grep supports '\|' when in basic regular expression mode, not all grep implementations do (notably toybox grep, used to build the Android kernel, does not). Switching to grep -Ev enables extended regular expressions which includes support for the '|' operator. Signed-off-by: Matthew Maurer <mmaurer@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Trevor Gross <tmgross@umich.edu> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20230928201421.2296518-1-mmaurer@google.com [ Reworded for typo. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-15rust: Use awk instead of recent xargsMatthew Maurer
`awk` is already required by the kernel build, and the `xargs` feature used in current Rust detection is not present in all `xargs` (notably, toybox based xargs, used in the Android kernel build). Signed-off-by: Matthew Maurer <mmaurer@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20230928205045.2375899-1-mmaurer@google.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-15rust: upgrade to Rust 1.73.0Miguel Ojeda
This is the next upgrade to the Rust toolchain, from 1.72.1 to 1.73.0 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4da06e ("rust: upgrade to Rust 1.68.2"). # Unstable features No unstable features (that we use) were stabilized. Therefore, the only unstable feature allowed to be used outside the `kernel` crate is still `new_uninit`, though other code to be upstreamed may increase the list. Please see [3] for details. # Required changes For the upgrade, the following changes are required: - Allow `internal_features` for `feature(compiler_builtins)` since now Rust warns about using internal compiler and standard library features (similar to how it also warns about incomplete ones) [4]. - A cleanup for a documentation link thanks to a new `rustdoc` lint. See previous commits for details. - A need to make an intra-doc link to a macro explicit, due to a change in behavior in `rustdoc`. See previous commits for details. # `alloc` upgrade and reviewing The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1730-2023-10-05 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: https://github.com/Rust-for-Linux/linux/issues/2 [3] Link: https://github.com/rust-lang/compiler-team/issues/596 [4] Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20231005210556.466856-4-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-15rust: print: use explicit link in documentationMiguel Ojeda
The future `rustdoc` in the Rust 1.73.0 upgrade requires an explicit link for `pr_info!`: error: unresolved link to `pr_info` --> rust/kernel/print.rs:395:63 | 395 | /// Use only when continuing a previous `pr_*!` macro (e.g. [`pr_info!`]). | ^^^^^^^^ no item named `pr_info` in scope | = note: `macro_rules` named `pr_info` exists in this crate, but it is not in scope at this link's location = note: `-D rustdoc::broken-intra-doc-links` implied by `-D warnings` Thus do so to avoid a broken link while upgrading. Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Finn Behrens <me@kloenk.dev> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20231005210556.466856-3-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-15rust: task: remove redundant explicit linkMiguel Ojeda
Starting with Rust 1.73.0, `rustdoc` detects redundant explicit links with its new lint `redundant_explicit_links` [1]: error: redundant explicit link target --> rust/kernel/task.rs:85:21 | 85 | /// [`current`](crate::current) macro because it is safe. | --------- ^^^^^^^^^^^^^^ explicit target is redundant | | | because label contains path that resolves to same destination | = note: when a link's destination is not specified, the label is used to resolve intra-doc links = note: `-D rustdoc::redundant-explicit-links` implied by `-D warnings` help: remove explicit link target | 85 | /// [`current`] macro because it is safe. In order to avoid the warning in the compiler upgrade commit, make it an intra-doc link as the tool suggests. Link: https://github.com/rust-lang/rust/pull/113167 [1] Reviewed-by: Finn Behrens <me@kloenk.dev> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Link: https://lore.kernel.org/r/20231005210556.466856-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-14rust: Respect HOSTCC when linking for hostMatthew Maurer
Currently, rustc defaults to invoking `cc`, even if `HOSTCC` is defined, resulting in build failures in hermetic environments where `cc` does not exist. This includes both hostprogs and proc-macros. Since we are setting the linker to `HOSTCC`, we set the linker flavor to `gcc` explicitly. The linker-flavor selects both which linker to search for if the linker is unset, and which kind of linker flags to pass. Without this flag, `rustc` would attempt to determine which flags to pass based on the name of the binary passed as `HOSTCC`. `gcc` is the name of the linker-flavor used by `rustc` for all C compilers, including both `gcc` and `clang`. Signed-off-by: Matthew Maurer <mmaurer@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Tested-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Nick Desaulniers <ndesaulniers@google.com> Acked-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2023-10-12rust: fix bindgen build error with fstrict-flex-arraysAndrea Righi
Commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") enabled '-fstrict-flex-arrays=3' globally, but bindgen does not recognized this compiler option, triggering the following build error: error: unknown argument: '-fstrict-flex-arrays=3', err: true [ Miguel: Commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") did it so only conditionally (i.e. only if the C compiler supports it). This explains what Andrea was seeing: he was compiling with a modern enough GCC, which enables the option, but with an old enough Clang. Andrea confirmed this was the case: he was using Clang 14 with GCC 13; and that Clang 15 worked for him. While it is possible to construct code (see mailing list for an example I came up with) where this could break, it is fairly contrived, and anyway GCC-built kernels with Rust enabled should only be used for experimentation until we get support for `rustc_codegen_gcc` and/or GCC Rust. So let's add this for the time being in case it helps somebody. ] Add '-fstrict-flex-arrays' to the list of cflags that should be ignored by bindgen. Fixes: df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3") Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Tested-by: Gary Guo <gary@garyguo.net> Link: https://lore.kernel.org/r/20230815065346.131387-1-andrea.righi@canonical.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-12rust: error: Markdown style nitManmohan Shukla
This patch fixes a trivial markdown style nit in the `SAFETY` comment. Signed-off-by: Manmohan Shukla <manmshuk@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Jianguo Bao <roidinev@gmail.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Reviewed-by: Finn Behrens <me@kloenk.dev> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Fixes: c7e20faa5fca ("rust: error: Add Error::to_ptr()") Link: https://lore.kernel.org/r/20230906204857.85619-1-manmshuk@gmail.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-12rust: error: fix the description for `ECHILD`Wedson Almeida Filho
A mistake was made and the description of `ECHILD` is wrong (it reuses the description of `ENOEXEC`). This fixes it to reflect what's in `errno-base.h`. Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Trevor Gross <tmgross@umich.edu> Reviewed-by: Finn Behrens <me@kloenk.dev> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Fixes: 266def2a0f5b ("rust: error: add codes from `errno-base.h`") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230930144958.46051-1-wedsonaf@gmail.com [ Use the plural, as noticed by Benno. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-05rust: kernel: remove `#[allow(clippy::new_ret_no_self)]`Gary Guo
Clippy triggered a false positive on its `new_ret_no_self` lint when using the `pin_init!` macro. Since Rust 1.67.0, that does not happen anymore, since Clippy learnt to not warn about `-> impl Trait<Self>` [1][2]. The kernel nowadays uses Rust 1.72.1, thus remove the `#[allow]`. Signed-off-by: Gary Guo <gary@garyguo.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Finn Behrens <me@kloenk.dev> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://github.com/rust-lang/rust-clippy/issues/7344 [1] Link: https://github.com/rust-lang/rust-clippy/pull/9733 [2] Link: https://lore.kernel.org/r/20230923024707.47610-1-gary@garyguo.net [ Reworded slightly and added a couple `Link`s. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-05rust: upgrade to Rust 1.72.1Miguel Ojeda
This is the third upgrade to the Rust toolchain, from 1.71.1 to 1.72.1 (i.e. the latest) [1]. See the upgrade policy [2] and the comments on the first upgrade in commit 3ed03f4da06e ("rust: upgrade to Rust 1.68.2"). # Unstable features No unstable features (that we use) were stabilized. Therefore, the only unstable feature allowed to be used outside the `kernel` crate is still `new_uninit`, though other code to be upstreamed may increase the list. Please see [3] for details. # Other improvements Previously, the compiler could incorrectly generate a `.eh_frame` section under `-Cpanic=abort`. We were hitting this bug when debug assertions were enabled (`CONFIG_RUST_DEBUG_ASSERTIONS=y`) [4]: LD .tmp_vmlinux.kallsyms1 ld.lld: error: <internal>:(.eh_frame) is being placed in '.eh_frame' Gary fixed the issue in Rust 1.72.0 [5]. # Required changes For the upgrade, the following changes are required: - A call to `Box::from_raw` in `rust/kernel/sync/arc.rs` now requires an explicit `drop()` call. See previous patch for details. # `alloc` upgrade and reviewing The vast majority of changes are due to our `alloc` fork being upgraded at once. There are two kinds of changes to be aware of: the ones coming from upstream, which we should follow as closely as possible, and the updates needed in our added fallible APIs to keep them matching the newer infallible APIs coming from upstream. Instead of taking a look at the diff of this patch, an alternative approach is reviewing a diff of the changes between upstream `alloc` and the kernel's. This allows to easily inspect the kernel additions only, especially to check if the fallible methods we already have still match the infallible ones in the new version coming from upstream. Another approach is reviewing the changes introduced in the additions in the kernel fork between the two versions. This is useful to spot potentially unintended changes to our additions. To apply these approaches, one may follow steps similar to the following to generate a pair of patches that show the differences between upstream Rust and the kernel (for the subset of `alloc` we use) before and after applying this patch: # Get the difference with respect to the old version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > old.patch git -C linux restore rust/alloc # Apply this patch. git -C linux am rust-upgrade.patch # Get the difference with respect to the new version. git -C rust checkout $(linux/scripts/min-tool-version.sh rustc) git -C linux ls-tree -r --name-only HEAD -- rust/alloc | cut -d/ -f3- | grep -Fv README.md | xargs -IPATH cp rust/library/alloc/src/PATH linux/rust/alloc/PATH git -C linux diff --patch-with-stat --summary -R > new.patch git -C linux restore rust/alloc Now one may check the `new.patch` to take a look at the additions (first approach) or at the difference between those two patches (second approach). For the latter, a side-by-side tool is recommended. Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1721-2023-09-19 [1] Link: https://rust-for-linux.com/rust-version-policy [2] Link: https://github.com/Rust-for-Linux/linux/issues/2 [3] Closes: https://github.com/Rust-for-Linux/linux/issues/1012 [4] Link: https://github.com/rust-lang/rust/pull/112403 [5] Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Link: https://lore.kernel.org/r/20230823160244.188033-3-ojeda@kernel.org [ Used 1.72.1 instead of .0 (no changes in `alloc`) and reworded to mention that we hit the `.eh_frame` bug under debug assertions. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-10-05rust: arc: add explicit `drop()` around `Box::from_raw()`Miguel Ojeda
`Box::from_raw()` is `#[must_use]`, which means the result cannot go unused. In Rust 1.71.0, this was not detected because the block expression swallows the diagnostic [1]: unsafe { Box::from_raw(self.ptr.as_ptr()) }; It would have been detected, however, if the line had been instead: unsafe { Box::from_raw(self.ptr.as_ptr()); } i.e. the semicolon being inside the `unsafe` block, rather than outside. In Rust 1.72.0, the compiler started warning about this [2], so without this patch we will get: error: unused return value of `alloc::boxed::Box::<T>::from_raw` that must be used --> rust/kernel/sync/arc.rs:302:22 | 302 | unsafe { Box::from_raw(self.ptr.as_ptr()) }; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ | = note: call `drop(Box::from_raw(ptr))` if you intend to drop the `Box` = note: `-D unused-must-use` implied by `-D warnings` help: use `let _ = ...` to ignore the resulting value | 302 | unsafe { let _ = Box::from_raw(self.ptr.as_ptr()); }; | +++++++ + Thus add an add an explicit `drop()` as the `#[must_use]`'s annotation suggests (instead of the more general help line). Link: https://github.com/rust-lang/rust/issues/104253 [1] Link: https://github.com/rust-lang/rust/pull/112529 [2] Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Link: https://lore.kernel.org/r/20230823160244.188033-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-09-25rust: workqueue: add examplesAlice Ryhl
This adds two examples of how to use the workqueue. The first example shows how to use it when you only have one `work_struct` field, and the second example shows how to use it when you have multiple `work_struct` fields. Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25rust: workqueue: add `try_spawn` helper methodAlice Ryhl
This adds a convenience method that lets you spawn a closure for execution on a workqueue. This will be the most convenient way to use workqueues, but it is fallible because it needs to allocate memory. Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25rust: workqueue: implement `WorkItemPointer` for pointer typesAlice Ryhl
This implements the `WorkItemPointer` trait for the pointer types that you are likely to use the workqueue with. The `Arc` type is for reference counted objects, and the `Pin<Box<T>>` type is for objects where the caller has exclusive ownership of the object. Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25rust: workqueue: add helper for defining work_struct fieldsAlice Ryhl
The main challenge with defining `work_struct` fields is making sure that the function pointer stored in the `work_struct` is appropriate for the work item type it is embedded in. It needs to know the offset of the `work_struct` field being used (even if there are several!) so that it can do a `container_of`, and it needs to know the type of the work item so that it can call into the right user-provided code. All of this needs to happen in a way that provides a safe API to the user, so that users of the workqueue cannot mix up the function pointers. There are three important pieces that are relevant when doing this: * The pointer type. * The work item struct. This is what the pointer points at. * The `work_struct` field. This is a field of the work item struct. This patch introduces a separate trait for each piece. The pointer type is given a `WorkItemPointer` trait, which pointer types need to implement to be usable with the workqueue. This trait will be implemented for `Arc` and `Box` in a later patch in this patchset. Implementing this trait is unsafe because this is where the `container_of` operation happens, but user-code will not need to implement it themselves. The work item struct should then implement the `WorkItem` trait. This trait is where user-code specifies what they want to happen when a work item is executed. It also specifies what the correct pointer type is. Finally, to make the work item struct know the offset of its `work_struct` field, we use a trait called `HasWork<T, ID>`. If a type implements this trait, then the type declares that, at the given offset, there is a field of type `Work<T, ID>`. The trait is marked unsafe because the OFFSET constant must be correct, but we provide an `impl_has_work!` macro that can safely implement `HasWork<T>` on a type. The macro expands to something that only compiles if the specified field really has the type `Work<T>`. It is used like this: ``` struct MyWorkItem { work_field: Work<MyWorkItem, 1>, } impl_has_work! { impl HasWork<MyWorkItem, 1> for MyWorkItem { self.work_field } } ``` Note that since the `Work` type is annotated with an id, you can have several `work_struct` fields by using a different id for each one. Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25rust: workqueue: define built-in queuesWedson Almeida Filho
We provide these methods because it lets us access these queues from Rust without using unsafe code. These methods return `&'static Queue`. References annotated with the 'static lifetime are used when the referent will stay alive forever. That is ok for these queues because they are global variables and cannot be destroyed. Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com> Co-developed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25rust: workqueue: add low-level workqueue bindingsAlice Ryhl
Define basic low-level bindings to a kernel workqueue. The API defined here can only be used unsafely. Later commits will provide safe wrappers. Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: "Andreas Hindborg (Samsung)" <nmi@metaspace.dk> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-09-25rust: sync: add `Arc::{from_raw, into_raw}`Wedson Almeida Filho
These methods can be used to turn an `Arc` into a raw pointer and back, in a way that preserves the metadata for fat pointers. This is done using the unstable ptr_metadata feature [1]. However, it could also be done using the unstable pointer_byte_offsets feature [2], which is likely to have a shorter path to stabilization than ptr_metadata. Link: https://github.com/rust-lang/rust/issues/81513 [1] Link: https://github.com/rust-lang/rust/issues/96283 [2] Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com> Co-developed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-08-30Merge tag 'docs-6.6' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "Documentation work keeps chugging along; this includes: - Work from Carlos Bilbao to integrate rustdoc output into the generated HTML documentation. This took some work to figure out how to do it without slowing the docs build and without creating people who don't have Rust installed, but Carlos got there - Move the loongarch and mips architecture documentation under Documentation/arch/ - Some more maintainer documentation from Jakub ... plus the usual assortment of updates, translations, and fixes" * tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits) Docu: genericirq.rst: fix irq-example input: docs: pxrc: remove reference to phoenix-sim Documentation: serial-console: Fix literal block marker docs/mm: remove references to hmm_mirror ops and clean typos docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add() Documentation: Fix typos Documentation/ABI: Fix typos scripts: kernel-doc: fix macro handling in enums scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN] Documentation: riscv: Update boot image header since EFI stub is supported Documentation: riscv: Add early boot document Documentation: arm: Add bootargs to the table of added DT parameters docs: kernel-parameters: Refer to the correct bitmap function doc: update params of memhp_default_state= docs: Add book to process/kernel-docs.rst docs: sparse: fix invalid link addresses docs: vfs: clean up after the iterate() removal docs: Add a section on surveys to the researcher guidelines docs: move mips under arch docs: move loongarch under arch ...
2023-08-29Merge tag 'rust-6.6' of https://github.com/Rust-for-Linux/linuxLinus Torvalds
Pull rust updates from Miguel Ojeda: "In terms of lines, most changes this time are on the pinned-init API and infrastructure. While we have a Rust version upgrade, and thus a bunch of changes from the vendored 'alloc' crate as usual, this time those do not account for many lines. Toolchain and infrastructure: - Upgrade to Rust 1.71.1. This is the second such upgrade, which is a smaller jump compared to the last time. This version allows us to remove the '__rust_*' allocator functions -- the compiler now generates them as expected, thus now our 'KernelAllocator' is used. It also introduces the 'offset_of!' macro in the standard library (as an unstable feature) which we will need soon. So far, we were using a declarative macro as a prerequisite in some not-yet-landed patch series, which did not support sub-fields (i.e. nested structs): #[repr(C)] struct S { a: u16, b: (u8, u8), } assert_eq!(offset_of!(S, b.1), 3); - Upgrade to bindgen 0.65.1. This is the first time we upgrade its version. Given it is a fairly big jump, it comes with a fair number of improvements/changes that affect us, such as a fix needed to support LLVM 16 as well as proper support for '__noreturn' C functions, which are now mapped to return the '!' type in Rust: void __noreturn f(void); // C pub fn f() -> !; // Rust - 'scripts/rust_is_available.sh' improvements and fixes. This series takes care of all the issues known so far and adds a few new checks to cover for even more cases, plus adds some more help texts. All this together will hopefully make problematic setups easier to identify and to be solved by users building the kernel. In addition, it adds a test suite which covers all branches of the shell script, as well as tests for the issues found so far. - Support rust-analyzer for out-of-tree modules too. - Give 'cfg's to rust-analyzer for the 'core' and 'alloc' crates. - Drop 'scripts/is_rust_module.sh' since it is not needed anymore. Macros crate: - New 'paste!' proc macro. This macro is a more flexible version of 'concat_idents!': it allows the resulting identifier to be used to declare new items and it allows to transform the identifiers before concatenating them, e.g. let x_1 = 42; paste!(let [<x _2>] = [<x _1>];); assert!(x_1 == x_2); The macro is then used for several of the pinned-init API changes in this pull. Pinned-init API: - Make '#[pin_data]' compatible with conditional compilation of fields, allowing to write code like: #[pin_data] pub struct Foo { #[cfg(CONFIG_BAR)] a: Bar, #[cfg(not(CONFIG_BAR))] a: Baz, } - New '#[derive(Zeroable)]' proc macro for the 'Zeroable' trait, which allows 'unsafe' implementations for structs where every field implements the 'Zeroable' trait, e.g.: #[derive(Zeroable)] pub struct DriverData { id: i64, buf_ptr: *mut u8, len: usize, } - Add '..Zeroable::zeroed()' syntax to the 'pin_init!' macro for zeroing all other fields, e.g.: pin_init!(Buf { buf: [1; 64], ..Zeroable::zeroed() }); - New '{,pin_}init_array_from_fn()' functions to create array initializers given a generator function, e.g.: let b: Box<[usize; 1_000]> = Box::init::<Error>( init_array_from_fn(|i| i) ).unwrap(); assert_eq!(b.len(), 1_000); assert_eq!(b[123], 123); - New '{,pin_}chain' methods for '{,Pin}Init<T, E>' that allow to execute a closure on the value directly after initialization, e.g.: let foo = init!(Foo { buf <- init::zeroed() }).chain(|foo| { foo.setup(); Ok(()) }); - Support arbitrary paths in init macros, instead of just identifiers and generic types. - Implement the 'Zeroable' trait for the 'UnsafeCell<T>' and 'Opaque<T>' types. - Make initializer values inaccessible after initialization. - Make guards in the init macros hygienic. 'allocator' module: - Use 'krealloc_aligned()' in 'KernelAllocator::alloc' preventing misaligned allocations when the Rust 1.71.1 upgrade is applied later in this pull. The equivalent fix for the previous compiler version (where 'KernelAllocator' is not yet used) was merged into 6.5 already, which added the 'krealloc_aligned()' function used here. - Implement 'KernelAllocator::{realloc, alloc_zeroed}' for performance, using 'krealloc_aligned()' too, which forwards the call to the C API. 'types' module: - Make 'Opaque' be '!Unpin', removing the need to add a 'PhantomPinned' field to Rust structs that contain C structs which must not be moved. - Make 'Opaque' use 'UnsafeCell' as the outer type, rather than inner. Documentation: - Suggest obtaining the source code of the Rust's 'core' library using the tarball instead of the repository. MAINTAINERS: - Andreas and Alice, from Samsung and Google respectively, are joining as reviewers of the "RUST" entry. As well as a few other minor changes and cleanups" * tag 'rust-6.6' of https://github.com/Rust-for-Linux/linux: (42 commits) rust: init: update expanded macro explanation rust: init: add `{pin_}chain` functions to `{Pin}Init<T, E>` rust: init: make `PinInit<T, E>` a supertrait of `Init<T, E>` rust: init: implement `Zeroable` for `UnsafeCell<T>` and `Opaque<T>` rust: init: add support for arbitrary paths in init macros rust: init: add functions to create array initializers rust: init: add `..Zeroable::zeroed()` syntax for zeroing all missing fields rust: init: make initializer values inaccessible after initializing rust: init: wrap type checking struct initializers in a closure rust: init: make guards in the init macros hygienic rust: add derive macro for `Zeroable` rust: init: make `#[pin_data]` compatible with conditional compilation of fields rust: init: consolidate init macros docs: rust: clarify what 'rustup override' does docs: rust: update instructions for obtaining 'core' source docs: rust: add command line to rust-analyzer section scripts: generate_rust_analyzer: provide `cfg`s for `core` and `alloc` rust: bindgen: upgrade to 0.65.1 rust: enable `no_mangle_with_rust_abi` Clippy lint rust: upgrade to Rust 1.71.1 ...
2023-08-28Merge tag 'linux-kselftest-kunit-6.6-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull kunit updates from Shuah Khan: - add support for running Rust documentation tests as KUnit tests - make init, str, sync, types doctests compilable/testable - add support for attributes API which include speed, modules attributes, ability to filter and report attributes - add support for marking tests slow using attributes API - add attributes API documentation - fix a wild-memory-access bug in kunit_filter_suites() and a possible memory leak in kunit_filter_suites() - add support for counting number of test suites in a module, list action to kunit test modules, and test filtering on module tests * tag 'linux-kselftest-kunit-6.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (25 commits) kunit: fix struct kunit_attr header kunit: replace KUNIT_TRIGGER_STATIC_STUB maro with KUNIT_STATIC_STUB_REDIRECT kunit: Allow kunit test modules to use test filtering kunit: Make 'list' action available to kunit test modules kunit: Report the count of test suites in a module kunit: fix uninitialized variables bug in attributes filtering kunit: fix possible memory leak in kunit_filter_suites() kunit: fix wild-memory-access bug in kunit_filter_suites() kunit: Add documentation of KUnit test attributes kunit: add tests for filtering attributes kunit: time: Mark test as slow using test attributes kunit: memcpy: Mark tests as slow using test attributes kunit: tool: Add command line interface to filter and report attributes kunit: Add ability to filter attributes kunit: Add module attribute kunit: Add speed attribute kunit: Add test attributes API structure MAINTAINERS: add Rust KUnit files to the KUnit entry rust: support running Rust documentation tests as KUnit ones rust: types: make doctests compilable/testable ...
2023-08-21rust: init: update expanded macro explanationBenno Lossin
The previous patches changed the internals of the macros resulting in the example expanded code being outdated. This patch updates the example and only changes documentation. Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-14-benno.lossin@proton.me Reviewed-by: Alice Ryhl <aliceryhl@google.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: add `{pin_}chain` functions to `{Pin}Init<T, E>`Benno Lossin
The `{pin_}chain` functions extend an initializer: it not only initializes the value, but also executes a closure taking a reference to the initialized value. This allows to do something with a value directly after initialization. Suggested-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20230814084602.25699-13-benno.lossin@proton.me [ Cleaned a few trivial nits. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: make `PinInit<T, E>` a supertrait of `Init<T, E>`Benno Lossin
Remove the blanket implementation of `PinInit<T, E> for I where I: Init<T, E>`. This blanket implementation prevented custom types that implement `PinInit`. Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-12-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: implement `Zeroable` for `UnsafeCell<T>` and `Opaque<T>`Benno Lossin
`UnsafeCell<T>` and `T` have the same layout so if `T` is `Zeroable` then so should `UnsafeCell<T>` be. This allows using the derive macro for `Zeroable` on types that contain an `UnsafeCell<T>`. Since `Opaque<T>` contains a `MaybeUninit<T>`, all bytes zero is a valid bit pattern for that type. Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-11-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: add support for arbitrary paths in init macrosBenno Lossin
Previously only `ident` and generic types were supported in the `{try_}{pin_}init!` macros. This patch allows arbitrary path fragments, so for example `Foo::Bar` but also very complex paths such as `<Foo as Baz>::Bar::<0, i32>`. Internally this is accomplished by using `path` fragments. Due to some peculiar declarative macro limitations, we have to "forget" certain additional parsing information in the token trees. This is achieved by using the `paste!` proc macro. It does not actually modify the input, since no `[< >]` will be present in the input, so it just strips the information held by declarative macros. For example, if a declarative macro takes `$t:path` as its input, it cannot sensibly propagate this to a macro that takes `$($p:tt)*` as its input, since the `$t` token will only be considered one `tt` token for the second macro. If we first pipe the tokens through `paste!`, then it parses as expected. Suggested-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-10-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: add functions to create array initializersBenno Lossin
Add two functions `pin_init_array_from_fn` and `init_array_from_fn` that take a function that generates initializers for `T` from `usize`, the added functions then return an initializer for `[T; N]` where every element is initialized by an element returned from the generator function. Suggested-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-9-benno.lossin@proton.me [ Cleaned a couple trivial nits. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: add `..Zeroable::zeroed()` syntax for zeroing all missing fieldsBenno Lossin
Add the struct update syntax to the init macros, but only for `..Zeroable::zeroed()`. Adding this at the end of the struct initializer allows one to omit fields from the initializer, these fields will be initialized with 0x00 set to every byte. Only types that implement the `Zeroable` trait can utilize this. Suggested-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-8-benno.lossin@proton.me [ Rebased on `rust-next` and cleaned a few trivial nits. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: make initializer values inaccessible after initializingBenno Lossin
Previously the init macros would create a local variable with the name and hygiene of the field that is being initialized to store the value of the field. This would override any user defined variables. For example: ``` struct Foo { a: usize, b: usize, } let a = 10; let foo = init!(Foo{ a: a + 1, // This creates a local variable named `a`. b: a, // This refers to that variable! }); let foo = Box::init!(foo)?; assert_eq!(foo.a, 11); assert_eq!(foo.b, 11); ``` This patch changes this behavior, so the above code would panic at the last assertion, since `b` would have value 10. Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-7-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: wrap type checking struct initializers in a closureBenno Lossin
In the implementation of the init macros there is a `if false` statement that type checks the initializer to ensure every field is initialized. Since the next patch has a stack variable to store the struct, the function might allocate too much memory on debug builds. Putting the struct into a closure that is never executed ensures that even in debug builds no stack overflow error is caused. In release builds this was not a problem since the code was optimized away due to the `if false`. Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-6-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-21rust: init: make guards in the init macros hygienicBenno Lossin
Use hygienic identifiers for the guards instead of the field names. This makes the init macros feel more like normal struct initializers, since assigning identifiers with the name of a field does not create conflicts. Also change the internals of the guards, no need to make the `forget` function `unsafe`, since users cannot access the guards anyways. Now the guards are carried directly on the stack and have no extra `Cell<bool>` field that marks if they have been forgotten or not, instead they are just forgotten via `mem::forget`. Suggested-by: Asahi Lina <lina@asahilina.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Link: https://lore.kernel.org/r/20230814084602.25699-5-benno.lossin@proton.me [ Cleaned a few trivial nits. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>