A new experimental Kconfig option, `RUST_INLINE_HELPERS` is added to
allow C helpers (which were created to allow Rust to call into
inline/macro C functions without having to re-implement the logic in
Rust) to be inlined into Rust crates without performing global LTO.
If the option is enabled, the following is performed:
* For helpers, instead of compiling them to an object file to be linked
into vmlinux, they're compiled to LLVM IR bitcode. Two versions are
generated: one for built-in code (`helpers.bc`) and one for modules
(`helpers_module.bc`, with -DMODULE defined). This ensures that C
macros/inlines that behave differently for modules (e.g. static calls)
function correctly when inlined.
* When a Rust crate or object is compiled, instead of generating an
object file, LLVM bitcode is generated.
* llvm-link is invoked with --internalize to combine the helper bitcode
with the crate bitcode. This step is similar to LTO, but this is much
faster since it only needs to inline the helpers.
* clang is invoked to turn the combined bitcode into a final object file.
* Since clang may produce LLVM bitcode when LTO is enabled, and objtool
requires ELF input, $(cmd_ld_single) is invoked to ensure the object
is converted to ELF before objtool runs.
The --internalize flag tells llvm-link to treat all symbols in
helpers.bc using `internal` linkage [1]. This matches the behavior of
`clang` on `static inline` functions, and avoids exporting the symbol
from the object file.
To ensure that RUST_INLINE_HELPERS is not incompatible with BTF, we pass
the -g0 flag when building helpers. See commit 5daa0c35a1 ("rust:
Disallow BTF generation with Rust + LTO") for details.
We have an intended triple mismatch of `aarch64-unknown-none` vs
`aarch64-unknown-linux-gnu`, so we pass --suppress-warnings to llvm-link
to suppress it.
I considered adding some sort of check that KBUILD_MODNAME is not
present in helpers_module.bc, but this is actually not so easy to carry
out because .bc files store strings in a weird binary format, so you
cannot just grep it for a string to check whether it ended up using
KBUILD_MODNAME anywhere.
[ Andreas writes:
For the rnull driver, enabling helper inlining with this patch
gives an average speedup of 2% over the set of 120 workloads that
we publish on [2].
Link: https://rust-for-linux.com/null-block-driver [2]
This series also uncovered a pre-existing UB instance thanks to an
`objtool` warning which I noticed while testing the series (details
in the mailing list).
- Miguel ]
Link: https://github.com/llvm/llvm-project/pull/170397 [1]
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Co-developed-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://patch.msgid.link/20260203-inline-helpers-v2-3-beb8547a03c9@google.com
[ Some changes, apart from the rebase:
- Added "(EXPERIMENTAL)" to Kconfig as the commit mentions.
- Added `depends on ARM64 || X86_64` and `!UML` for now, since this is
experimental, other architectures may require other changes (e.g.
the issues I mentioned in the mailing list for ARM and UML) and they
are not really tested so far. So let arch maintainers pick this up
if they think it is worth it.
- Gated the `cmd_ld_single` step also into the new mode, which also
means that any possible future `objcopy` step is done after the
translation, as expected.
- Added `.gitignore` for `.bc` with exception for existing script.
- Added `part-of-*` for helpers bitcode files as discussed, and
dropped `$(if $(filter %_module.bc,$@),-DMODULE)` since `-DMODULE`
is already there (would be duplicated otherwise).
- Moved `LLVM_LINK` to keep binutils list alphabetized.
- Fixed typo in title.
- Dropped second `cmd_ld_single` commit message paragraph.
- Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The macro is a more powerful version of `static_assert!` for use inside
function contexts. This is powered by inline consts, so enable the feature
for old compiler versions that does not have it stably.
While it is possible already to write `const { assert!(...) }`, this
provides a short hand that is more uniform with other assertions. It also
formats nicer with rustfmt where it will not be formatted into multiple
lines.
Two users that would route via the Rust tree are converted.
Reviewed-by: Yury Norov <ynorov@nvidia.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260319121653.2975748-3-gary@kernel.org
[ Rebased. Fixed period typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The decodecode script always returns an exit code of 1, regardless of
whether the operation was successful or not. This is because the
"cleanup" function, which is registered to run on any script exit via
"trap cleanup EXIT", contains an unconditional "exit 1".
Remove the "exit 1" from the "cleanup" function so that it only performs
the necessary file cleanup without forcing a non-zero exit status.
Do that to ensure successful script executions now exit with code 0.
Exits due to errors are all handled by the "die()" function and will still
correctly exit with code 1.
Link: https://lkml.kernel.org/r/20260318150545.2809311-1-derkling@google.com
Signed-off-by: Patrick Bellasi <derkling@google.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The Assisted-by tag was introduced in
Documentation/process/coding-assistants.rst for attributing AI tool
contributions to kernel patches. However, checkpatch.pl did not recognize
this tag, causing two issues:
WARNING: Non-standard signature: Assisted-by:
ERROR: Unrecognized email address: 'AGENT_NAME:MODEL_VERSION'
Fix this by:
1. Adding Assisted-by to the recognized $signature_tags list
2. Skipping email validation for Assisted-by lines since they use the
AGENT_NAME:MODEL_VERSION format instead of an email address
3. Warning when the Assisted-by value doesn't match the expected format
Link: https://lkml.kernel.org/r/20260311215818.518930-1-sashal@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
Reported-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Joe Perches <joe@perches.com>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Decode the caller address instead of the return address by default. This
also introduced -R option to provide return address decoding mode.
This changes the decode_stacktrace.sh to decode the line info 1byte before
the return address which will be the call(branch) instruction address. If
the return address is a symbol address (zero offset from it), it falls
back to decoding the return address.
This improves results especially when optimizations have changed the order
of the lines around the return address, or when the return address does
not have the actual line information.
With this change;
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:94 lib/dump_stack.c:120)
lockdep_rcu_suspicious (kernel/locking/lockdep.c:6876)
event_filter_pid_sched_process_fork (kernel/trace/trace_events.c:1057)
kernel_clone (include/trace/events/sched.h:396 include/trace/events/sched.h:396 kernel/fork.c:2664)
__x64_sys_clone (kernel/fork.c:2795 kernel/fork.c:2779 kernel/fork.c:2779)
do_syscall_64 (arch/x86/entry/syscall_64.c:63 arch/x86/entry/syscall_64.c:94)
? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
? trace_irq_disable (include/trace/events/preemptirq.h:36)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:121)
Without this (or give -R option);
Call Trace:
<TASK>
dump_stack_lvl (lib/dump_stack.c:122)
lockdep_rcu_suspicious (kernel/locking/lockdep.c:6877)
event_filter_pid_sched_process_fork (kernel/trace/trace_events.c:?)
kernel_clone (include/trace/events/sched.h:? include/trace/events/sched.h:396 kernel/fork.c:2664)
__x64_sys_clone (kernel/fork.c:2779)
do_syscall_64 (arch/x86/entry/syscall_64.c:?)
? entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
? trace_irq_disable (include/trace/events/preemptirq.h:36)
entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130)
[akpm@linux-foundation.org: fix spello]
Link: https://lkml.kernel.org/r/177275821652.1557019.18367881408364381866.stgit@mhiramat.tok.corp.google.com
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com> [arm64]
Cc: Carlos Llamas <cmllamas@google.com>
Cc: Sasha Levin (Microsoft) <sashal@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add support for the ** glob operator in MAINTAINERS F: and X: patterns,
matching any number of path components (like Python's ** glob).
The existing * to .* conversion with slash-count check is preserved. **
is converted to (?:.*), a non-capturing group used as a marker to bypass
the slash-count check in file_match_pattern(), allowing the pattern to
cross directory boundaries.
This enables patterns like F: **/*[_-]kunit*.c to match files at any depth
in the tree.
Link: https://lkml.kernel.org/r/20260302103822.77343-1-teknoraver@meta.com
Signed-off-by: Matteo Croce <teknoraver@meta.com>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Pull hardening fixes from Kees Cook:
- fix required Clang version for CC_HAS_COUNTED_BY_PTR (Nathan
Chancellor)
- update Coccinelle script used for kmalloc_obj
* tag 'hardening-v7.0-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
init/Kconfig: Require a release version of clang-22 for CC_HAS_COUNTED_BY_PTR
coccinelle: kmalloc_obj: Remove default GFP_KERNEL arg
Pull Kbuild fixes from Nathan Chancellor:
"This mostly addresses some issues with the awk conversion in
scripts/kconfig/merge_config.sh.
- Fix typo to ensure .builtin-dtbs.S is properly cleaned
- Fix '==' bashism in scripts/kconfig/merge_config.sh
- Fix awk error in scripts/kconfig/merge_config.sh when base
configuration is empty
- Fix inconsistent indentation in scripts/kconfig/merge_config.sh"
* tag 'kbuild-fixes-7.0-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
scripts: kconfig: merge_config.sh: fix indentation
scripts: kconfig: merge_config.sh: pass output file as awk variable
scripts: kconfig: merge_config.sh: fix unexpected operator warning
kbuild: Delete .builtin-dtbs.S when running make clean
Now that the UAPI headers provide the required definitions, use those.
Some symbols have been renamed, adapt to those.
Also adapt the include path for the custom sign-file rule in the
bpf selftests.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Resolve conflict between this change in the upstream kernel:
4c652a4772 ("rseq: Mark rseq_arm_slice_extension_timer() __always_inline")
... and this pending change in timers/core:
0e98eb1481 ("entry: Prepare for deferred hrtimer rearming")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When ${CROSS_COMPILE} is set, but ${CC} is not set, the logic in
check-uapi.sh is different from the top-level Makefile, which defaults
to using the cross gcc. This leads to using the native gcc instead of the
cross version, resulting in unexpected false-positive and false-negative
output.
Use the same logic here that we use in Kbuild for consistency.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20260306163309.2015837-3-arnd@kernel.org
Signed-off-by: Nicolas Schier <nsc@kernel.org>
Sources already have SPDX-FileCopyrightText (~40 instances) and more
appear on the mailing list, so document that it is allowed. On the
other hand SPDX defines several other tags like SPDX-FileType, so add
checkpatch rule to narrow desired tags only to two of them - license and
copyright. That way no new tags would sneak in to the kernel unnoticed.
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Joe Perches <joe@perches.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 1ba9f89794 ("vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and
related macros") added .text and made .data, .bss, and .rodata sections
unconditional in the module linker script, but without an explicit
address like the other sections in the same file.
When linking modules with ld.bfd -r, sections defined without an address
inherit the location counter, resulting in non-zero sh_addr values in
the .ko. Relocatable objects are expected to have sh_addr=0 for these
sections and these non-zero addresses confuse elfutils and have been
reported to cause segmentation faults in SystemTap [1].
Add the 0 address specifier to all sections in module.lds, including the
.codetag.* sections via MOD_SEPARATE_CODETAG_SECTIONS macro.
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=33958
Fixes: 1ba9f89794 ("vmlinux.lds: Unify TEXT_MAIN, DATA_MAIN, and related macros")
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
It is a pain in the ass to compare the software versions on the running
system (scripts/ver_linux) with the minimal required versions.
Sorting both lists the same way makes side-by-side comparisons a simple task.
fix path to changes.rst
make toolnames uniform with the toolnames in Changes.rst
make version commands uniform with Changes.rst
Add missing tools in ver_linux
bash, bc, bindgen, btrfs-progs, Clang, gdb, GNU awk, GNU tar,
GRUB, GRUB2, gtags, iptables, kmod, mcelog, mkimage, openssl,
pahole, Python, Rust, Sphinx, squashfs-tools
Signed-off-by: Manuel Ebner <manuelebner@airmail.cc>
Message-ID: <20260311165440.183672-2-manuelebner@airmail.cc>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Capture the output of the patch command to detect when a patch applies
with fuzz or line offsets.
If such "fuzz" is detected during the validation phase, warn the user
and display the details. This helps identify input patches that may
need refreshing against the target source tree.
Ensure that internal patch operations (such as those in refresh_patch or
during the final build phase) can still run quietly.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/20260310203751.1479229-13-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Update SHORT_CIRCUIT behavior to better handle patch validation and
argument processing in later klp-build steps.
Perform patch validation for both step 1 (building original kernel) and
step 2 (building patched kernel) to ensure patches are verified before
any compilation occurs.
Additionally, allow the user to omit input patches when skipping past
step 2.
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-9-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Fix or suppress the following shellcheck warnings:
In klp-build line 57:
command grep "$@" || true
^--^ SC2317 (info): Command appears to be unreachable. Check usage (or ignore if invoked indirectly).
Fix the following warning:
In klp-build line 565:
local file_dir="$(dirname "$file")"
^------^ SC2034 (warning): file_dir appears unused. Verify use (or export if used externally).
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-8-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
The klp-build script is currently very strict with input patches,
requiring them to apply cleanly via `git apply --recount`. This
prevents the use of patches with minor contextual fuzz relative to the
target kernel sources.
To allow users to reuse a patch across similar kernel streams, switch to
using GNU patch and patchutils for intermediate patch manipulation.
Update the logic for applying, reverting, and regenerating patches:
- Use 'patch -p1' for better handling of context fuzz.
- Use 'recountdiff' to update line counts after FIX_PATCH_LINES.
- Drop git_refresh() and related git-specific logic.
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Song Liu <song@kernel.org>
Link: https://patch.msgid.link/20260310203751.1479229-5-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
The klp-build script prepares a clean patch by populating two temporary
directories ('a' and 'b') with source files and diffing the result.
However, this process fails when a patch introduces a new source file,
as the script attempts to copy files that do not yet exist in the
original source tree. Likewise, it fails when a patch removes a source
file and the script attempts to copy a file that no longer exists.
Refactor the file-gathering logic to distinguish between original input
files and patched output files:
- Split get_patch_files() into get_patch_input_files() and
get_patch_output_files() to identify which files exist before and
after patch application.
- Filter out "/dev/null" from both to handle file creation/deletion.
- Update refresh_patch() to only copy existing input files to the 'a'
directory and the resulting output files to the 'b' directory.
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-4-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Introduce CC_FLAGS_DIALECT to make it easier to update the various
places in the tree that rely on the GNU C standard and Microsoft
extensions flags atomically. All remaining uses of '-std=gnu11' and
'-fms-extensions' are in the tools directory (which has its own build
system) and other standalone Makefiles. This will allow the kernel to
use a narrower option to enable the Microsoft anonymous tagged structure
extension in a simpler manner. Place the CC_FLAGS_DIALECT block after
the configuration include (so that a future change can move the
selection of the flag to Kconfig) but before the
arch/$(SRCARCH)/Makefile include (so that CC_FLAGS_DIALECT is available
for use in those Makefiles).
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Helge Deller <deller@gmx.de> # parisc
Link: https://patch.msgid.link/20260223-fms-anonymous-structs-v1-1-8ee406d3c36c@kernel.org
Signed-off-by: Nicolas Schier <nsc@kernel.org>
The refactoring commit 5fa9b82cbc ("scripts: kconfig:
merge_config.sh: refactor from shell/sed/grep to awk") passes
$TMP_FILE.new as ARGV[3] to awk, using it as both an output destination
and an input file argument. When the base file is empty, nothing is
written to ARGV[3] during processing, so awk fails trying to open it
for reading:
awk: cmd. line:52: fatal: cannot open file
`./.tmp.config.grcQin34jb.new' for reading: No such file or directory
mv: cannot stat './.tmp.config.grcQin34jb.new': No such file or directory
Pass the output path via -v outfile instead and drop the FILENAME ==
ARGV[3] { nextfile }.
Fixes: 5fa9b82cbc ("scripts: kconfig: merge_config.sh: refactor from shell/sed/grep to awk")
Signed-off-by: Daniel Gomez <da.gomez@samsung.com>
Link: https://patch.msgid.link/20260310-fixes-merge-config-v1-1-beaeeaded6bd@samsung.com
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Fix a warning for:
$ ./scripts/kconfig/merge_config.sh .config extra.config
Using .config as base
Merging extra.config
./scripts/kconfig/merge_config.sh: 384: [: false: unexpected operator
The shellcheck report is also attached:
if [ "$STRICT" == "true" ] && [ "$STRICT_MODE_VIOLATED" == "true" ]; then
^-- SC3014 (warning): In POSIX sh, == in place of = is undefined.
^-- SC3014 (warning): In POSIX sh, == in place of = is undefined.
Fixes: dfc97e1c5d ("scripts: kconfig: merge_config.sh: use awk in checks too")
Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Reviewed-by: Mikko Rapeli <mikko.rapeli@linaro.org>
Link: https://patch.msgid.link/20260309121505.40454-1-o451686892@gmail.com
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Add a FIPS cryptographic algorithm self-test for AES-CMAC to fulfill the
self-test requirement when this code is built into a FIPS 140
cryptographic module. This provides parity with the traditional crypto
API, which uses crypto/testmgr.c to meet the FIPS self-test requirement.
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20260218213501.136844-8-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
