linux/rust/Makefile, branch v6.14

rust: kbuild: do not export generated KASAN ODR symbols

2025-02-06T18:47:04Z

ASAN generates special synthetic symbols to help check for ODR violations. These synthetic symbols lack debug information, so gendwarfksyms emits warnings when processing them. No code should ever have a dependency on these symbols, so we should not be exporting them, just like the __cfi symbols. Signed-off-by: Matthew Maurer Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20250122-gendwarfksyms-kasan-rust-v1-1-5ee5658f4fb6@google.com [ Fixed typo in commit message. Slightly reworded title. - Miguel ] Signed-off-by: Miguel Ojeda

rust: kbuild: add -fzero-init-padding-bits to bindgen_skip_cflags

2025-02-06T16:13:13Z

This seems to break the build when building with gcc15: Unable to generate bindings: ClangDiagnostic("error: unknown argument: '-fzero-init-padding-bits=all'\n") Thus skip that flag. Signed-off-by: Justin M. Forbes Fixes: dce4aab8441d ("kbuild: Use -fzero-init-padding-bits=all") Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20250129215003.1736127-1-jforbes@fedoraproject.org [ Slightly reworded commit. - Miguel ] Signed-off-by: Miguel Ojeda

rust: kbuild: use host dylib naming in rusttestlib-kernel

2025-02-05T23:15:27Z

There seems to have been merge skew between commit b2c261fa8629 ("rust: kbuild: expand rusttest target for macros") and commit 0730422bced5 ("rust: use host dylib naming convention to support macOS") ; the latter replaced `libmacros.so` with `$(libmacros_name)` and the former added an instance of `libmacros.so`. The former was not yet applied when the latter was sent, resulting in a stray `libmacros.so`. Replace the stray with `$(libmacros_name)` to allow `rusttest` to build on macOS. Fixes: 0730422bced5 ("rust: use host dylib naming convention to support macOS") Signed-off-by: Tamir Duberstein Link: https://lore.kernel.org/r/20250201-fix-mac-build-again-v1-1-ca665f5d7de7@gmail.com [ Slightly reworded title. - Miguel ] Signed-off-by: Miguel Ojeda

Merge tag 'kbuild-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2025-01-31T20:07:07Z

Pull Kbuild updates from Masahiro Yamada: - Support multiple hook locations for maint scripts of Debian package - Remove 'cpio' from the build tool requirement - Introduce gendwarfksyms tool, which computes CRCs for export symbols based on the DWARF information - Support CONFIG_MODVERSIONS for Rust - Resolve all conflicts in the genksyms parser - Fix several syntax errors in genksyms * tag 'kbuild-v6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (64 commits) kbuild: fix Clang LTO with CONFIG_OBJTOOL=n kbuild: Strip runtime const RELA sections correctly kconfig: fix memory leak in sym_warn_unmet_dep() kconfig: fix file name in warnings when loading KCONFIG_DEFCONFIG_LIST genksyms: fix syntax error for attribute before init-declarator genksyms: fix syntax error for builtin (u)int*x*_t types genksyms: fix syntax error for attribute after 'union' genksyms: fix syntax error for attribute after 'struct' genksyms: fix syntax error for attribute after abstact_declarator genksyms: fix syntax error for attribute before nested_declarator genksyms: fix syntax error for attribute before abstract_declarator genksyms: decouple ATTRIBUTE_PHRASE from type-qualifier genksyms: record attributes consistently for init-declarator genksyms: restrict direct-declarator to take one parameter-type-list genksyms: restrict direct-abstract-declarator to take one parameter-type-list genksyms: remove Makefile hack genksyms: fix last 3 shift/reduce conflicts genksyms: fix 6 shift/reduce conflicts and 5 reduce/reduce conflicts genksyms: reduce type_qualifier directly to decl_specifier genksyms: rename cvar_qualifier to type_qualifier ...

rust: Use gendwarfksyms + extended modversions for CONFIG_MODVERSIONS

2025-01-17T23:51:48Z

Previously, two things stopped Rust from using MODVERSIONS: 1. Rust symbols are occasionally too long to be represented in the original versions table 2. Rust types cannot be properly hashed by the existing genksyms approach because: * Looking up type definitions in Rust is more complex than C * Type layout is potentially dependent on the compiler in Rust, not just the source type declaration. CONFIG_EXTENDED_MODVERSIONS addresses the first point, and CONFIG_GENDWARFKSYMS the second. If Rust wants to use MODVERSIONS, allow it to do so by selecting both features. Signed-off-by: Sami Tolvanen Co-developed-by: Matthew Maurer Signed-off-by: Matthew Maurer Signed-off-by: Masahiro Yamada

kbuild: rust: add PROCMACROLDFLAGS

2025-01-15T08:53:54Z

These are flags to be passed when linking proc macros for the Rust toolchain. If unset, it defaults to $(KBUILD_HOSTLDFLAGS). This is needed because the list of flags to link hostprogs is not necessarily the same as the list of flags used to link libmacros.so. When we build proc macros, we need the latter, not the former (e.g. when using a Rust compiler binary linked to a different C library than host programs). To distinguish between the two, introduce this new variable to stand out from KBUILD_HOSTLDFLAGS used to link other host progs. Signed-off-by: HONG Yifan Link: https://lore.kernel.org/r/20241017210430.2401398-2-elsk@google.com [ v3: - `export`ed the variable. Otherwise it would not be visible in `rust/Makefile`. - Removed "additional" from the documentation and commit message, since this actually replaces the other flags, unlike other cases. - Added example of use case to documentation and commit message. Thanks Alice for the details on what Google needs! - Instead of `HOSTLDFLAGS`, used `KBUILD_HOSTLDFLAGS` as the fallback to preserve the previous behavior as much as possible, as discussed with Alice/Yifan. Thus moved the variable down too (currently we do not modify `KBUILD_HOSTLDFLAGS` elsewhere) and avoided mentioning `HOSTLDFLAGS` directly in the documentation. - Fixed documentation header formatting. - Reworded slightly. - Miguel ] Tested-by: Alice Ryhl Reviewed-by: Alice Ryhl Reviewed-by: HONG Yifan Acked-by: Masahiro Yamada Link: https://lore.kernel.org/r/20241112184455.855133-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda

rust: use host dylib naming convention to support macOS

2025-01-10T00:01:24Z

Because the `macros` crate exposes procedural macros, it must be compiled as a dynamic library (so it can be loaded by the compiler at compile-time). Before this change the resulting artifact was always named `libmacros.so`, which works on hosts where this matches the naming convention for dynamic libraries. However the proper name on macOS would be `libmacros.dylib`. This turns out to matter even when the dependency is passed with a path (`--extern macros=path/to/libmacros.so` rather than `--extern macros`) because rustc uses the file name to infer the type of the library (see link). This is because there's no way to specify both the path to and the type of the external library via CLI flags. The compiler could speculatively parse the file to determine its type, but it does not do so today. This means that libraries that match neither rustc's naming convention for static libraries nor the platform's naming convention for dynamic libraries are *rejected*. The only solution I've found is to follow the host platform's naming convention. This patch does that by querying the compiler to determine the appropriate name for the artifact. This allows the kernel to build with CONFIG_RUST=y on macOS. Link: https://github.com/rust-lang/rust/blob/d829780/compiler/rustc_metadata/src/locator.rs#L728-L752 Tested-by: Daniel Gomez Co-developed-by: Fiona Behrens Signed-off-by: Fiona Behrens Signed-off-by: Tamir Duberstein Tested-by: Andreas Hindborg Link: https://lore.kernel.org/r/20241216-b4-dylib-host-macos-v7-1-cfc507681447@gmail.com [ Added `MAKEFLAGS=`s to avoid jobserver warnings. Removed space. Reworded title. - Miguel ] Signed-off-by: Miguel Ojeda

rust: kbuild: run Clippy for `rusttest` code

2025-01-09T23:17:25Z

Running Clippy for `rusttest` code is useful to catch issues there too, even if the code is not as critical. In the future, this code may also run in kernelspace and could be copy-pasted. Thus it is useful to keep it under the same standards. For instance, it will now make us add `// SAFETY` comments. It also makes everything more consistent. Thus clean the few issues spotted by Clippy and start running it. Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20241123180639.260191-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda

rust: kbuild: set `bindgen`'s Rust target version

2024-12-10T00:06:10Z

Each `bindgen` release may upgrade the list of Rust targets. For instance, currently, in their master branch [1], the latest ones are: Nightly => { vectorcall_abi: #124485, ptr_metadata: #81513, layout_for_ptr: #69835, }, Stable_1_77(77) => { offset_of: #106655 }, Stable_1_73(73) => { thiscall_abi: #42202 }, Stable_1_71(71) => { c_unwind_abi: #106075 }, Stable_1_68(68) => { abi_efiapi: #105795 }, By default, the highest stable release in their list is used, and users are expected to set one if they need to support older Rust versions (e.g. see [2]). Thus, over time, new Rust features are used by default, and at some point, it is likely that `bindgen` will emit Rust code that requires a Rust version higher than our minimum (or perhaps enabling an unstable feature). Currently, there is no problem because the maximum they have, as seen above, is Rust 1.77.0, and our current minimum is Rust 1.78.0. Therefore, set a Rust target explicitly now to prevent going forward in time too much and thus getting potential build failures at some point. Since we also support a minimum `bindgen` version, and since `bindgen` does not support passing unknown Rust target versions, we need to use the list of our minimum `bindgen` version, rather than the latest. So, since `bindgen` 0.65.1 had this list [3], we need to use Rust 1.68.0: /// Rust stable 1.64 /// * `core_ffi_c` ([Tracking issue](https://github.com/rust-lang/rust/issues/94501)) => Stable_1_64 => 1.64; /// Rust stable 1.68 /// * `abi_efiapi` calling convention ([Tracking issue](https://github.com/rust-lang/rust/issues/65815)) => Stable_1_68 => 1.68; /// Nightly rust /// * `thiscall` calling convention ([Tracking issue](https://github.com/rust-lang/rust/issues/42202)) /// * `vectorcall` calling convention (no tracking issue) /// * `c_unwind` calling convention ([Tracking issue](https://github.com/rust-lang/rust/issues/74990)) => Nightly => nightly; ... /// Latest stable release of Rust pub const LATEST_STABLE_RUST: RustTarget = RustTarget::Stable_1_68; Thus add the `--rust-target 1.68` parameter. Add a comment as well explaining this. An alternative would be to use the currently running (i.e. actual) `rustc` and `bindgen` versions to pick a "better" Rust target version. However, that would introduce more moving parts depending on the user setup and is also more complex to implement. Starting with `bindgen` 0.71.0 [4], we will be able to set any future Rust version instead, i.e. we will be able to set here our minimum supported Rust version. Christian implemented it [5] after seeing this patch. Thanks! Cc: Christian Poveda Cc: Emilio Cobos Álvarez Cc: stable@vger.kernel.org # needed for 6.12.y; unneeded for 6.6.y; do not apply to 6.1.y Fixes: c844fa64a2d4 ("rust: start supporting several `bindgen` versions") Link: https://github.com/rust-lang/rust-bindgen/blob/21c60f473f4e824d4aa9b2b508056320d474b110/bindgen/features.rs#L97-L105 [1] Link: https://github.com/rust-lang/rust-bindgen/issues/2960 [2] Link: https://github.com/rust-lang/rust-bindgen/blob/7d243056d335fdc4537f7bca73c06d01aae24ddc/bindgen/features.rs#L131-L150 [3] Link: https://github.com/rust-lang/rust-bindgen/blob/main/CHANGELOG.md#0710-2024-12-06 [4] Link: https://github.com/rust-lang/rust-bindgen/pull/2993 [5] Reviewed-by: Alice Ryhl Link: https://lore.kernel.org/r/20241123180323.255997-1-ojeda@kernel.org Signed-off-by: Miguel Ojeda

Merge tag 'kbuild-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2024-11-30T21:41:50Z

Pull Kbuild updates from Masahiro Yamada: - Add generic support for built-in boot DTB files - Enable TAB cycling for dialog buttons in nconfig - Fix issues in streamline_config.pl - Refactor Kconfig - Add support for Clang's AutoFDO (Automatic Feedback-Directed Optimization) - Add support for Clang's Propeller, a profile-guided optimization. - Change the working directory to the external module directory for M= builds - Support building external modules in a separate output directory - Enable objtool for *.mod.o and additional kernel objects - Use lz4 instead of deprecated lz4c - Work around a performance issue with "git describe" - Refactor modpost * tag 'kbuild-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (85 commits) kbuild: rename .tmp_vmlinux.kallsyms0.syms to .tmp_vmlinux0.syms gitignore: Don't ignore 'tags' directory kbuild: add dependency from vmlinux to resolve_btfids modpost: replace tdb_hash() with hash_str() kbuild: deb-pkg: add python3:native to build dependency genksyms: reduce indentation in export_symbol() modpost: improve error messages in device_id_check() modpost: rename alias symbol for MODULE_DEVICE_TABLE() modpost: rename variables in handle_moddevtable() modpost: move strstarts() to modpost.h modpost: convert do_usb_table() to a generic handler modpost: convert do_of_table() to a generic handler modpost: convert do_pnp_device_entry() to a generic handler modpost: convert do_pnp_card_entries() to a generic handler modpost: call module_alias_printf() from all do_*_entry() functions modpost: pass (struct module *) to do_*_entry() functions modpost: remove DEF_FIELD_ADDR_VAR() macro modpost: deduplicate MODULE_ALIAS() for all drivers modpost: introduce module_alias_printf() helper modpost: remove unnecessary check in do_acpi_entry() ...