Add a top-level target for building gen_init_cpio to prevent re-entering
kbuild for 'modules-cpio-pkg'.
The recently introduced target 'modules-cpio-pkg' depends on
gen_init_cpio but there is no simple way to add this dependency as a
prerequisite that can be built in parallel to other recipes.
Introducing the top-level target, enables fixing this and also prepares
a possible move of gen_init_cpio from usr/ to scripts/.
Signed-off-by: Nicolas Schier <nsc@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20251128-kbuild-add-top-level-target-for-building-gen_init_cpio-v1-1-84c63a8fc8d4@kernel.org
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
This patch implements kconfig re-sync when the pahole version changes
between builds, similar to how it happens for compiler version change
via CC_VERSION_TEXT.
Define PAHOLE_VERSION in the top-level Makefile and export it for
config builds. Set CONFIG_PAHOLE_VERSION default to the exported
variable.
Kconfig records the PAHOLE_VERSION value in
include/config/auto.conf.cmd [1].
The Makefile includes auto.conf.cmd, so if PAHOLE_VERSION changes
between builds, make detects a dependency change and triggers
syncconfig to update the kconfig [2].
For external module builds, add a warning message in the prepare
target, similar to the existing compiler version mismatch warning.
Note that if pahole is not installed or available, PAHOLE_VERSION is
set to 0 by pahole-version.sh, so the (un)installation of pahole is
treated as a version change.
See previous discussions for context [3].
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/scripts/kconfig/preprocess.c?h=v6.18#n91
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Makefile?h=v6.18#n815
[3] https://lore.kernel.org/bpf/8f946abf-dd88-4fac-8bb4-84fcd8d81cf0@oracle.com/
Signed-off-by: Ihor Solodrai <ihor.solodrai@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Nicolas Schier <nsc@kernel.org>
Tested-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://lore.kernel.org/bpf/20251219181321.1283664-6-ihor.solodrai@linux.dev
Running the full 'make dt_binding_check' is slow. A shortcut is to set
DT_SCHEMA_FILES env variable to a substring of DT schema files to test.
It both limits which examples are validated and which schemas are used
to validate the examples. This is a problem because errors from other
schemas are missed. What makes validation slow is checking all examples,
so we really just need a way to test a single example.
Add a %.yaml target to validate the schema and validate the example:
make example-schema.yaml
The behavior for 'make dt_binding_check DT_SCHEMA_FILES=example-schema'
is unchanged. Really it should mirror dtbs_check and validate all the
examples with a subset of schemas, but there are lots of users of
expecting the existing behavior.
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Link: https://patch.msgid.link/20251208224304.2907913-1-robh@kernel.org
Signed-off-by: Rob Herring (Arm) <robh@kernel.org>
If a tracepoint is defined but never used (TRACE_EVENT() created but no
trace_<tracepoint>() called), it can take up to or more than 5K of memory
each. This can add up as there are around a hundred unused tracepoints with
various configs. That is 500K of wasted memory.
Add a make build parameter of "UT=1" to have the build warn if an unused
tracepoint is detected in the build. This allows detection of unused
tracepoints to be upstream so that outreachy and the mentoring project can
have new developers look for fixing them, without having these warnings
suddenly show up when someone upgrades their kernel. When all known unused
tracepoints are removed, then the "UT=1" build parameter can be removed and
unused tracepoints will always warn. This will catch new unused tracepoints
after the current ones have been removed.
- Separate out elf functions from sorttable.c
Move out the ELF parsing functions from sorttable.c so that the tracing
tooling can use it.
- Add a tracepoint verifier tool to the build process
If "UT=1" is added to the kernel command line, any unused tracepoints will
trigger a warning at build time.
- Do not warn about unused tracepoints for tracepoints that are exported
There are sever cases where a tracepoint is created by the kernel and used
by modules. Since there's no easy way to detect if these are truly unused
since the users are in modules, if a tracepoint is exported, assume it
will eventually be used by a module. Note, there's not many exported
tracepoints so this should not be a problem to ignore them.
- Have building of modules also detect unused tracepoints
Do not only check the main vmlinux for unused tracepoints, also check
modules. If a module is defining a tracepoint it should be using it.
- Add the tracepoint-update program to the ignore file
The new tracepoint-update program needs to be ignored by git.
-----BEGIN PGP SIGNATURE-----
iIoEABYKADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCaS9iLxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qk4mAP96T/IPPjox1Fd7r/Dpm+JNfYom8AZ8
WGNL06+aEKRWZwEAqc+u/9k3r964k+pKQ7qwL3ZslG2ALSOdKbFXHpsPpw8=
=R/qK
-----END PGP SIGNATURE-----
Merge tag 'tracepoints-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull unused tracepoints update from Steven Rostedt:
"Detect unused tracepoints.
If a tracepoint is defined but never used (TRACE_EVENT() created but
no trace_<tracepoint>() called), it can take up to or more than 5K of
memory each. This can add up as there are around a hundred unused
tracepoints with various configs. That is 500K of wasted memory.
Add a make build parameter of "UT=1" to have the build warn if an
unused tracepoint is detected in the build. This allows detection of
unused tracepoints to be upstream so that outreachy and the mentoring
project can have new developers look for fixing them, without having
these warnings suddenly show up when someone upgrades their kernel.
When all known unused tracepoints are removed, then the "UT=1" build
parameter can be removed and unused tracepoints will always warn. This
will catch new unused tracepoints after the current ones have been
removed.
Summary:
- Separate out elf functions from sorttable.c
Move out the ELF parsing functions from sorttable.c so that the
tracing tooling can use it.
- Add a tracepoint verifier tool to the build process
If "UT=1" is added to the kernel command line, any unused
tracepoints will trigger a warning at build time.
- Do not warn about unused tracepoints for tracepoints that are
exported
There are sever cases where a tracepoint is created by the kernel
and used by modules. Since there's no easy way to detect if these
are truly unused since the users are in modules, if a tracepoint is
exported, assume it will eventually be used by a module. Note,
there's not many exported tracepoints so this should not be a
problem to ignore them.
- Have building of modules also detect unused tracepoints
Do not only check the main vmlinux for unused tracepoints, also
check modules. If a module is defining a tracepoint it should be
using it.
- Add the tracepoint-update program to the ignore file
The new tracepoint-update program needs to be ignored by git"
* tag 'tracepoints-v6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
scripts: add tracepoint-update to the list of ignores files
tracing: Add warnings for unused tracepoints for modules
tracing: Allow tracepoint-update.c to work with modules
tracepoint: Do not warn for unused event that is exported
tracing: Add a tracepoint verification check at build time
sorttable: Move ELF parsing into scripts/elf-parse.[ch]
- string: Add missing kernel-doc return descriptions (Kriish Sharma)
- Update some mis-typed allocations
- Enable GCC diagnostic context for value-tracking warnings
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCaS9E5QAKCRA2KwveOeQk
u5lYAQDEXFBD3+X+k9LNuPS/FLpz5sEI0SOI4lD8xDEjhtmygAD+LVV8yRf6ajPA
5O2f4hbKnP5+4XHwSiG+CV7QpAgHHwo=
=6GEw
-----END PGP SIGNATURE-----
Merge tag 'hardening-v6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening updates from Kees Cook:
- string: Add missing kernel-doc return descriptions (Kriish Sharma)
- Update some mis-typed allocations
These correct some accidentally wrong types used in allocations (that
didn't affect the resulting size) that never got picked up from the
batch I sent a few months ago.
- Enable GCC diagnostic context for value-tracking warnings
This results in better GCC diagnostics for the value range tracking,
so we can get better visibility into where those values are coming
from when we get out-of-bounds warnings at compile time.
* tag 'hardening-v6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
kbuild: Enable GCC diagnostic context for value-tracking warnings
string: Add missing kernel-doc return descriptions
media: iris: Cast iris_hfi_gen2_get_instance() allocation type
drm/plane: Remove const qualifier from plane->modifiers allocation type
comedi: Adjust range_table_list allocation type
- Enable -fms-extensions, allowing anonymous use of tagged struct or
union in struct/union (tag kbuild-ms-extensions-6.19). An exemplary
conversion patch is added here, too (btrfs).
- Introduce architecture-specific CC_CAN_LINK and flags for userprogs
- Add new packaging target 'modules-cpio-pkg' for building a initramfs
cpio w/ kmods
- Handle included .c files in gen_compile_commands
- Minor kbuild changes:
- Use objtree for module signing key path, fixing oot kmod signing
- Improve documentation of KBUILD_BUILD_TIMESTAMP
- Reuse KBUILD_USERCFLAGS for UAPI, instead of defining twice
- Rename scripts/Makefile.extrawarn to Makefile.warn
- Drop obsolete types.h check from headers_check.pl
- Remove outdated config leak ignore entries
Signed-off-by: Nicolas Schier <nsc@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Gn4V
-----END PGP SIGNATURE-----
Merge tag 'kbuild-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux
Pull Kbuild updates from Nicolas Schier:
- Enable -fms-extensions, allowing anonymous use of tagged struct or
union in struct/union (tag kbuild-ms-extensions-6.19). An exemplary
conversion patch is added here, too (btrfs).
[ Editor's note: the core of this actually came in early through a
shared branch and a few other trees - Linus ]
- Introduce architecture-specific CC_CAN_LINK and flags for userprogs
- Add new packaging target 'modules-cpio-pkg' for building a initramfs
cpio w/ kmods
- Handle included .c files in gen_compile_commands
- Minor kbuild changes:
- Use objtree for module signing key path, fixing oot kmod signing
- Improve documentation of KBUILD_BUILD_TIMESTAMP
- Reuse KBUILD_USERCFLAGS for UAPI, instead of defining twice
- Rename scripts/Makefile.extrawarn to Makefile.warn
- Drop obsolete types.h check from headers_check.pl
- Remove outdated config leak ignore entries
* tag 'kbuild-6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
kbuild: add target to build a cpio containing modules
initramfs: add gen_init_cpio to hostprogs unconditionally
kbuild: allow architectures to override CC_CAN_LINK
init: deduplicate cc-can-link.sh invocations
kbuild: don't enable CC_CAN_LINK if the dummy program generates warnings
scripts: headers_install.sh: Remove two outdated config leak ignore entries
scripts/clang-tools: Handle included .c files in gen_compile_commands
kbuild: uapi: Drop types.h check from headers_check.pl
kbuild: Rename Makefile.extrawarn to Makefile.warn
MAINTAINERS, .mailmap: Update mail address for Nicolas Schier
kbuild: uapi: reuse KBUILD_USERCFLAGS
kbuild: doc: improve KBUILD_BUILD_TIMESTAMP documentation
kbuild: Use objtree for module signing key path
btrfs: send: make use of -fms-extensions for defining struct fs_path
Toolchain and infrastructure:
- Add support for 'syn'.
Syn is a parsing library for parsing a stream of Rust tokens into a
syntax tree of Rust source code.
Currently this library is geared toward use in Rust procedural
macros, but contains some APIs that may be useful more generally.
'syn' allows us to greatly simplify writing complex macros such as
'pin-init' (Benno has already prepared the 'syn'-based version). We
will use it in the 'macros' crate too.
'syn' is the most downloaded Rust crate (according to crates.io), and
it is also used by the Rust compiler itself. While the amount of code
is substantial, there should not be many updates needed for these
crates, and even if there are, they should not be too big, e.g. +7k
-3k lines across the 3 crates in the last year.
'syn' requires two smaller dependencies: 'quote' and 'proc-macro2'.
I only modified their code to remove a third dependency
('unicode-ident') and to add the SPDX identifiers. The code can be
easily verified to exactly match upstream with the provided scripts.
They are all licensed under "Apache-2.0 OR MIT", like the other
vendored 'alloc' crate we had for a while.
Please see the merge commit with the cover letter for more context.
- Allow 'unreachable_pub' and 'clippy::disallowed_names' for doctests.
Examples (i.e. doctests) may want to do things like show public items
and use names such as 'foo'.
Nevertheless, we still try to keep examples as close to real code as
possible (this is part of why running Clippy on doctests is important
for us, e.g. for safety comments, which userspace Rust does not
support yet but we are stricter).
'kernel' crate:
- Replace our custom 'CStr' type with 'core::ffi::CStr'.
Using the standard library type reduces our custom code footprint,
and we retain needed custom functionality through an extension trait
and a new 'fmt!' macro which replaces the previous 'core' import.
This started in 6.17 and continued in 6.18, and we finally land the
replacement now. This required quite some stamina from Tamir, who
split the changes in steps to prepare for the flag day change here.
- Replace 'kernel::c_str!' with C string literals.
C string literals were added in Rust 1.77, which produce '&CStr's
(the 'core' one), so now we can write:
c"hi"
instead of:
c_str!("hi")
- Add 'num' module for numerical features.
It includes the 'Integer' trait, implemented for all primitive
integer types.
It also includes the 'Bounded' integer wrapping type: an integer
value that requires only the 'N' less significant bits of the wrapped
type to be encoded:
// An unsigned 8-bit integer, of which only the 4 LSBs are used.
let v = Bounded::<u8, 4>:🆕:<15>();
assert_eq!(v.get(), 15);
'Bounded' is useful to e.g. enforce guarantees when working with
bitfields that have an arbitrary number of bits.
Values can be constructed from simple non-constant expressions or,
for more complex ones, validated at runtime.
'Bounded' also comes with comparison and arithmetic operations (with
both their backing type and other 'Bounded's with a compatible
backing type), casts to change the backing type, extending/shrinking
and infallible/fallible conversions from/to primitives as applicable.
- 'rbtree' module: add immutable cursor ('Cursor').
It enables to use just an immutable tree reference where appropriate.
The existing fully-featured mutable cursor is renamed to 'CursorMut'.
kallsyms:
- Fix wrong "big" kernel symbol type read from procfs.
'pin-init' crate:
- A couple minor fixes (Benno asked me to pick these patches up for
him this cycle).
Documentation:
- Quick Start guide: add Debian 13 (Trixie).
Debian Stable is now able to build Linux, since Debian 13 (released
2025-08-09) packages Rust 1.85.0, which is recent enough.
We are planning to propose that the minimum supported Rust version in
Linux follows Debian Stable releases, with Debian 13 being the first
one we upgrade to, i.e. Rust 1.85.
MAINTAINERS:
- Add entry for the new 'num' module.
- Remove Alex as Rust maintainer: he hasn't had the time to contribute
for a few years now, so it is a no-op change in practice.
And a few other cleanups and improvements.
-----BEGIN PGP SIGNATURE-----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=9nM+
-----END PGP SIGNATURE-----
Merge tag 'rust-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Add support for 'syn'.
Syn is a parsing library for parsing a stream of Rust tokens into a
syntax tree of Rust source code.
Currently this library is geared toward use in Rust procedural
macros, but contains some APIs that may be useful more generally.
'syn' allows us to greatly simplify writing complex macros such as
'pin-init' (Benno has already prepared the 'syn'-based version). We
will use it in the 'macros' crate too.
'syn' is the most downloaded Rust crate (according to crates.io),
and it is also used by the Rust compiler itself. While the amount
of code is substantial, there should not be many updates needed for
these crates, and even if there are, they should not be too big,
e.g. +7k -3k lines across the 3 crates in the last year.
'syn' requires two smaller dependencies: 'quote' and 'proc-macro2'.
I only modified their code to remove a third dependency
('unicode-ident') and to add the SPDX identifiers. The code can be
easily verified to exactly match upstream with the provided
scripts.
They are all licensed under "Apache-2.0 OR MIT", like the other
vendored 'alloc' crate we had for a while.
Please see the merge commit with the cover letter for more context.
- Allow 'unreachable_pub' and 'clippy::disallowed_names' for
doctests.
Examples (i.e. doctests) may want to do things like show public
items and use names such as 'foo'.
Nevertheless, we still try to keep examples as close to real code
as possible (this is part of why running Clippy on doctests is
important for us, e.g. for safety comments, which userspace Rust
does not support yet but we are stricter).
'kernel' crate:
- Replace our custom 'CStr' type with 'core::ffi::CStr'.
Using the standard library type reduces our custom code footprint,
and we retain needed custom functionality through an extension
trait and a new 'fmt!' macro which replaces the previous 'core'
import.
This started in 6.17 and continued in 6.18, and we finally land the
replacement now. This required quite some stamina from Tamir, who
split the changes in steps to prepare for the flag day change here.
- Replace 'kernel::c_str!' with C string literals.
C string literals were added in Rust 1.77, which produce '&CStr's
(the 'core' one), so now we can write:
c"hi"
instead of:
c_str!("hi")
- Add 'num' module for numerical features.
It includes the 'Integer' trait, implemented for all primitive
integer types.
It also includes the 'Bounded' integer wrapping type: an integer
value that requires only the 'N' least significant bits of the
wrapped type to be encoded:
// An unsigned 8-bit integer, of which only the 4 LSBs are used.
let v = Bounded::<u8, 4>:🆕:<15>();
assert_eq!(v.get(), 15);
'Bounded' is useful to e.g. enforce guarantees when working with
bitfields that have an arbitrary number of bits.
Values can also be constructed from simple non-constant expressions
or, for more complex ones, validated at runtime.
'Bounded' also comes with comparison and arithmetic operations
(with both their backing type and other 'Bounded's with a
compatible backing type), casts to change the backing type,
extending/shrinking and infallible/fallible conversions from/to
primitives as applicable.
- 'rbtree' module: add immutable cursor ('Cursor').
It enables to use just an immutable tree reference where
appropriate. The existing fully-featured mutable cursor is renamed
to 'CursorMut'.
kallsyms:
- Fix wrong "big" kernel symbol type read from procfs.
'pin-init' crate:
- A couple minor fixes (Benno asked me to pick these patches up for
him this cycle).
Documentation:
- Quick Start guide: add Debian 13 (Trixie).
Debian Stable is now able to build Linux, since Debian 13 (released
2025-08-09) packages Rust 1.85.0, which is recent enough.
We are planning to propose that the minimum supported Rust version
in Linux follows Debian Stable releases, with Debian 13 being the
first one we upgrade to, i.e. Rust 1.85.
MAINTAINERS:
- Add entry for the new 'num' module.
- Remove Alex as Rust maintainer: he hasn't had the time to
contribute for a few years now, so it is a no-op change in
practice.
And a few other cleanups and improvements"
* tag 'rust-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (53 commits)
rust: macros: support `proc-macro2`, `quote` and `syn`
rust: syn: enable support in kbuild
rust: syn: add `README.md`
rust: syn: remove `unicode-ident` dependency
rust: syn: add SPDX License Identifiers
rust: syn: import crate
rust: quote: enable support in kbuild
rust: quote: add `README.md`
rust: quote: add SPDX License Identifiers
rust: quote: import crate
rust: proc-macro2: enable support in kbuild
rust: proc-macro2: add `README.md`
rust: proc-macro2: remove `unicode_ident` dependency
rust: proc-macro2: add SPDX License Identifiers
rust: proc-macro2: import crate
rust: kbuild: support using libraries in `rustc_procmacro`
rust: kbuild: support skipping flags in `rustc_test_library`
rust: kbuild: add proc macro library support
rust: kbuild: simplify `--cfg` handling
rust: kbuild: introduce `core-flags` and `core-skip_flags`
...
build-system thrashing. That work should slow down from here on out.
- The various scripts and tools for documentation were spread out in
several directories; now they are (almost) all coalesced under
tools/docs/. The holdout is the kernel-doc script, which cannot be
easily moved without some further thought.
- As the amount of Python code increases, we are accumulating modules that
are imported by multiple programs. These modules have been pulled
together under tools/lib/python/ -- at least, for documentation-related
programs. There is other Python code in the tree that might eventually
want to move toward this organization.
- The Perl kernel-doc.pl script has been removed. It is no longer used by
default, and nobody has missed it, least of all anybody who actually had
to look at it.
- The docs build was controlled by a complex mess of makefilese that few
dared to touch. Mauro has moved that logic into a new program
(tools/docs/sphinx-build-wrapper) that, with any luck at all, will be far
easier to understand and maintain.
- The get_feat.pl program, used to access information under
Documentation/features/, has been rewritten in Python, bringing an end to
the use of Perl in the docs subsystem.
- The top-level README file has been reorganized into a more
reader-friendly presentation.
- A lot of Chinese translation additions
- Typo fixes and documentation updates as usual
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmkuHzEACgkQF0NaE2wM
flgiqAf/aFUA3zCMvOSjbOpX8EO/4rs0ISkhhb01rLSMsRs3P+v9SlGVJls734BE
0ZvVmBo0p7mNakZD4tFCryFn8Gntn28smCEmpDu/FRDMOEcXFUqxQ9st9OhRlar2
tETdFIKIF+yncFJ83Mjr7F5Yeqg38m82g5JdTxvh6FmvDhPLiSXDEeBV2L7hU+St
EX8D8KOZH74XM8LMr8eg3GbUXx72A7WELndlF7DfGIAC8rFC3C9wa0CUSx8wz2Zh
CoCOYsrmd7WdB+c30SUmQbtYLVyWraiqVQVUlCdZDeYPBT/mTo6zJI5L0WxgXuHz
6o+fQdfLA7zlMHTelVcM6y4Qwkmayg==
=1TPY
-----END PGP SIGNATURE-----
Merge tag 'docs-6.19' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"This has been another busy cycle for documentation, with a lot of
build-system thrashing. That work should slow down from here on out.
- The various scripts and tools for documentation were spread out in
several directories; now they are (almost) all coalesced under
tools/docs/. The holdout is the kernel-doc script, which cannot be
easily moved without some further thought.
- As the amount of Python code increases, we are accumulating modules
that are imported by multiple programs. These modules have been
pulled together under tools/lib/python/ -- at least, for
documentation-related programs. There is other Python code in the
tree that might eventually want to move toward this organization.
- The Perl kernel-doc.pl script has been removed. It is no longer
used by default, and nobody has missed it, least of all anybody who
actually had to look at it.
- The docs build was controlled by a complex mess of makefilese that
few dared to touch. Mauro has moved that logic into a new program
(tools/docs/sphinx-build-wrapper) that, with any luck at all, will
be far easier to understand and maintain.
- The get_feat.pl program, used to access information under
Documentation/features/, has been rewritten in Python, bringing an
end to the use of Perl in the docs subsystem.
- The top-level README file has been reorganized into a more
reader-friendly presentation.
- A lot of Chinese translation additions
- Typo fixes and documentation updates as usual"
* tag 'docs-6.19' of git://git.lwn.net/linux: (164 commits)
docs: makefile: move rustdoc check to the build wrapper
README: restructure with role-based documentation and guidelines
docs: kdoc: various fixes for grammar, spelling, punctuation
docs: kdoc_parser: use '@' for Excess enum value
docs: submitting-patches: Clarify that removal of Acks needs explanation too
docs: kdoc_parser: add data/function attributes to ignore
docs: MAINTAINERS: update Mauro's files/paths
docs/zh_CN: Add wd719x.rst translation
docs/zh_CN: Add libsas.rst translation
get_feat.pl: remove it, as it got replaced by get_feat.py
Documentation/sphinx/kernel_feat.py: use class directly
tools/docs/get_feat.py: convert get_feat.pl to Python
Documentation/admin-guide: fix typo and comment in cscope example
docs/zh_CN: Add data-integrity.rst translation
docs/zh_CN: Add blk-mq.rst translation
docs/zh_CN: Add block/index.rst translation
docs/zh_CN: Update the Chinese translation of kbuild.rst
docs: bring some order to our Python module hierarchy
docs: Move the python libraries to tools/lib/python
Documentation/kernel-parameters: Move the kernel build options
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaSmOZAAKCRCRxhvAZXjc
onGCAQDEHKNEuZMhkyd3K5YsJtMzZlW/uXp4+Wddeob+5yQp0wEA09xN4CJNMwhP
J6Kjaa80hWfrFacqSvyMUwQHHw6mngs=
=5Mom
-----END PGP SIGNATURE-----
Merge tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"Features:
- Cheaper MAY_EXEC handling for path lookup. This elides MAY_WRITE
permission checks during path lookup and adds the
IOP_FASTPERM_MAY_EXEC flag so filesystems like btrfs can avoid
expensive permission work.
- Hide dentry_cache behind runtime const machinery.
- Add German Maglione as virtiofs co-maintainer.
Cleanups:
- Tidy up and inline step_into() and walk_component() for improved
code generation.
- Re-enable IOCB_NOWAIT writes to files. This refactors file
timestamp update logic, fixing a layering bypass in btrfs when
updating timestamps on device files and improving FMODE_NOCMTIME
handling in VFS now that nfsd started using it.
- Path lookup optimizations extracting slowpaths into dedicated
routines and adding branch prediction hints for mntput_no_expire(),
fd_install(), lookup_slow(), and various other hot paths.
- Enable clang's -fms-extensions flag, requiring a JFS rename to
avoid conflicts.
- Remove spurious exports in fs/file_attr.c.
- Stop duplicating union pipe_index declaration. This depends on the
shared kbuild branch that brings in -fms-extensions support which
is merged into this branch.
- Use MD5 library instead of crypto_shash in ecryptfs.
- Use largest_zero_folio() in iomap_dio_zero().
- Replace simple_strtol/strtoul with kstrtoint/kstrtouint in init and
initrd code.
- Various typo fixes.
Fixes:
- Fix emergency sync for btrfs. Btrfs requires an explicit sync_fs()
call with wait == 1 to commit super blocks. The emergency sync path
never passed this, leaving btrfs data uncommitted during emergency
sync.
- Use local kmap in watch_queue's post_one_notification().
- Add hint prints in sb_set_blocksize() for LBS dependency on THP"
* tag 'vfs-6.19-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (35 commits)
MAINTAINERS: add German Maglione as virtiofs co-maintainer
fs: inline step_into() and walk_component()
fs: tidy up step_into() & friends before inlining
orangefs: use inode_update_timestamps directly
btrfs: fix the comment on btrfs_update_time
btrfs: use vfs_utimes to update file timestamps
fs: export vfs_utimes
fs: lift the FMODE_NOCMTIME check into file_update_time_flags
fs: refactor file timestamp update logic
include/linux/fs.h: trivial fix: regualr -> regular
fs/splice.c: trivial fix: pipes -> pipe's
fs: mark lookup_slow() as noinline
fs: add predicts based on nd->depth
fs: move mntput_no_expire() slowpath into a dedicated routine
fs: remove spurious exports in fs/file_attr.c
watch_queue: Use local kmap in post_one_notification()
fs: touch up predicts in path lookup
fs: move fd_install() slowpath into a dedicated routine and provide commentary
fs: hide dentry_cache behind runtime const machinery
fs: touch predicts in do_dentry_open()
...
Enable GCC 16's coming "-fdiagnostics-show-context=N" option[1] to
provide enhanced diagnostic information for value-tracking warnings,
which displays the control flow chain leading to the diagnostic. This
covers our existing use of -Wrestrict and -Wstringop-overread, and
gets us closer to enabling -Warray-bounds, -Wstringop-overflow, and
-Wstringop-truncation, so we can track the rationale for the warning,
letting us more quickly identify actual issues vs what have looked in
the past like false positives. Fixes based on this work have already
been landing, e.g.:
4a6f18f286 ("net/mlx4_core: Avoid impossible mlx4_db_alloc() order value")
8a39f1c870 ("ovl: Check for NULL d_inode() in ovl_dentry_upper()")
e5f7e4e0a4 ("drm/amdgpu/atom: Work around vbios NULL offset false positive")
The context depth ("=N") provides the immediate decision path that led
to the problematic code location, showing conditional checks and branch
decisions that caused the warning. This will help us understand why
GCC's value-tracking analysis triggered the warning and makes it easier
to determine whether warnings are legitimate issues or false positives.
For example, an array bounds warning will now show the conditional
statements (like "if (i >= 4)") that established the out-of-bounds access
range, directly connecting the control flow to the warning location.
This is particularly valuable when GCC's interprocedural analysis can
generate warnings that are difficult to understand without seeing the
inferred control flow.
While my testing has shown that "=1" reports enough for finding
the origin of most bounds issues, I have used "=2" here just to be
conservative. Build time measurements with this option off, =1, and =2
are all with noise of each other, so there seems to be no harm in "turning
it up". If we need to, we can make this value configurable in the future.
Link: https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=6faa3cfe60ff9769d1bebfffdd2c7325217d7389 [1]
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20251121184342.it.626-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
With all the new files in place and ready from the new crate, enable
the support for it in the build system.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Gary Guo <gary@garyguo.net>
Tested-by: Jesung Yang <y.j3ms.n@gmail.com>
Link: https://patch.msgid.link/20251124151837.2184382-20-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
With all the new files in place and ready from the new crate, enable
the support for it in the build system.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Gary Guo <gary@garyguo.net>
Tested-by: Jesung Yang <y.j3ms.n@gmail.com>
Link: https://patch.msgid.link/20251124151837.2184382-15-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
With all the new files in place and ready from the new crate, enable
the support for it in the build system.
`proc_macro_byte_character` and `proc_macro_c_str_literals` were
stabilized in Rust 1.79.0 [1] and were implemented earlier than our
minimum Rust version (1.78) [2][3]. Thus just enable them instead of using
the `cfg` that `proc-macro2` uses to emulate them in older compilers.
In addition, skip formatting for this vendored crate and take the chance
to add a comment mentioning this.
Link: https://github.com/rust-lang/rust/pull/123431 [1]
Link: https://github.com/rust-lang/rust/pull/112711 [2]
Link: https://github.com/rust-lang/rust/pull/119651 [3]
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Gary Guo <gary@garyguo.net>
Tested-by: Jesung Yang <y.j3ms.n@gmail.com>
Link: https://patch.msgid.link/20251124151837.2184382-11-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The generic test for CC_CAN_LINK assumes that all architectures use -m32
and -m64 to switch between 32-bit and 64-bit compilation. This is overly
simplistic. Architectures may use other flags (-mabi, -m31, etc.) or may
also require byte order handling (-mlittle-endian, -EL). Expressing all
of the different possibilities will be very complicated and brittle.
Instead allow architectures to supply their own logic which will be
easy to understand and evolve.
Both the boolean ARCH_HAS_CC_CAN_LINK and the string ARCH_USERFLAGS need
to be implemented as kconfig does not allow the reuse of string options.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20251114-kbuild-userprogs-bits-v3-3-4dee0d74d439@linutronix.de
Signed-off-by: Nicolas Schier <nsc@kernel.org>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQR74yXHMTGczQHYypIdayaRccAalgUCaQzbRwAKCRAdayaRccAa
ls8lAP9Dj1mOl+KTtajMvDnDTym4Sso9CaFP+5maFAv9CflAIwEA5QEtSwI9sMcH
ty8x9Y6TTuib+ns37i2jxR8cIt4jHwU=
=WA6M
-----END PGP SIGNATURE-----
gpgsig -----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaRGyjgAKCRCRxhvAZXjc
okJ7AQDFRmoidpqHmRlvZQ3aismKkNHfx2k67QtRlX+YxDi8rQEAmmKyKUiX/SZV
39TroGfiJ5ytQuXwz3QxG/34cA+kAgQ=
=HqhX
-----END PGP SIGNATURE-----
Merge patch "kbuild: Add '-fms-extensions' to areas with dedicated CFLAGS"
Nathan Chancellor <nathan@kernel.org> says:
Shared branch between Kbuild and other trees for enabling
'-fms-extensions' for 6.19.
* tag 'kbuild-ms-extensions-6.19' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
kbuild: Add '-fms-extensions' to areas with dedicated CFLAGS
Kbuild: enable -fms-extensions
jfs: Rename _inline to avoid conflict with clang's '-fms-extensions'
Link: https://patch.msgid.link/20251101-kbuild-ms-extensions-dedicated-cflags-v1-1-38004aba524b@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>
Since commit e88ca24319 ("kbuild: consolidate warning flags in
scripts/Makefile.extrawarn"), scripts/Makefile.extrawarn contains all
warnings for the main kernel build, not just warnings enabled by the
values for W=. Rename it to scripts/Makefile.warn to make it clearer
that this Makefile is where all Kbuild warning handling should exist.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patch.msgid.link/20251023-rename-scripts-makefile-extrawarn-v1-1-8f7531542169@kernel.org
Signed-off-by: Nicolas Schier <nsc@kernel.org>
If a tracepoint is defined via DECLARE_TRACE() or TRACE_EVENT() but never
called (via the trace_<tracepoint>() function), its metadata is still
around in memory and not discarded.
When created via TRACE_EVENT() the situation is worse because the
TRACE_EVENT() creates metadata that can be around 5k per trace event.
Having unused trace events causes several thousand of wasted bytes.
Add a verifier that injects a string of the name of the tracepoint it
calls that is added to the discarded section "__tracepoint_check".
For every builtin tracepoint, its name (which is saved in the in-memory
section "__tracepoint_strings") will have its name also in the
"__tracepoint_check" section if it is used.
Add a new program that is run on build called tracepoint-update. This is
executed on the vmlinux.o before the __tracepoint_check section is
discarded (the section is discarded before vmlinux is created). This
program will create an array of each string in the __tracepoint_check
section and then sort it. Then it will walk the strings in the
__tracepoint_strings section and do a binary search to check if its name
is in the __tracepoint_check section. If it is not, then it is unused and
a warning is printed.
Note, this currently only handles tracepoints that are builtin and not in
modules.
Enabling this currently with a given config produces:
warning: tracepoint 'sched_move_numa' is unused.
warning: tracepoint 'sched_stick_numa' is unused.
warning: tracepoint 'sched_swap_numa' is unused.
warning: tracepoint 'pelt_hw_tp' is unused.
warning: tracepoint 'pelt_irq_tp' is unused.
warning: tracepoint 'rcu_preempt_task' is unused.
warning: tracepoint 'rcu_unlock_preempted_task' is unused.
warning: tracepoint 'xdp_bulk_tx' is unused.
warning: tracepoint 'xdp_redirect_map' is unused.
warning: tracepoint 'xdp_redirect_map_err' is unused.
warning: tracepoint 'vma_mas_szero' is unused.
warning: tracepoint 'vma_store' is unused.
warning: tracepoint 'hugepage_set_pmd' is unused.
warning: tracepoint 'hugepage_set_pud' is unused.
warning: tracepoint 'hugepage_update_pmd' is unused.
warning: tracepoint 'hugepage_update_pud' is unused.
warning: tracepoint 'block_rq_remap' is unused.
warning: tracepoint 'xhci_dbc_handle_event' is unused.
warning: tracepoint 'xhci_dbc_handle_transfer' is unused.
warning: tracepoint 'xhci_dbc_gadget_ep_queue' is unused.
warning: tracepoint 'xhci_dbc_alloc_request' is unused.
warning: tracepoint 'xhci_dbc_free_request' is unused.
warning: tracepoint 'xhci_dbc_queue_request' is unused.
warning: tracepoint 'xhci_dbc_giveback_request' is unused.
warning: tracepoint 'tcp_ao_wrong_maclen' is unused.
warning: tracepoint 'tcp_ao_mismatch' is unused.
warning: tracepoint 'tcp_ao_key_not_found' is unused.
warning: tracepoint 'tcp_ao_rnext_request' is unused.
warning: tracepoint 'tcp_ao_synack_no_key' is unused.
warning: tracepoint 'tcp_ao_snd_sne_update' is unused.
warning: tracepoint 'tcp_ao_rcv_sne_update' is unused.
Some of the above is totally unused but others are not used due to their
"trace_" functions being inside configs, in which case, the defined
tracepoints should also be inside those same configs. Others are
architecture specific but defined in generic code, where they should
either be moved to the architecture or be surrounded by #ifdef for the
architectures they are for.
This tool could be updated to process modules in the future.
I'd like to thank Mathieu Desnoyers for suggesting using strings instead
of pointers, as using pointers in vmlinux.o required handling relocations
and it required implementing almost a full feature linker to do so.
To enable this check, run the build with: make UT=1
Note, when all the existing unused tracepoints are removed from the build,
the "UT=1" will be removed and this will always be enabled when
tracepoints are configured to warn on any new tracepoints. The reason this
isn't always enabled now is because it will introduce a lot of warnings
for the current unused tracepoints, and all bisects would end at this
commit for those warnings.
Link: https://lore.kernel.org/all/20250528114549.4d8a5e03@gandalf.local.home/
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas.schier@linux.dev>
Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/20251022004452.920728129@kernel.org
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> # for using strings instead of pointers
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Quoth Mauro:
This series should probably be called:
"Move the trick-or-treat build hacks accumulated over time
into a single place and document them."
as this reflects its main goal. As such:
- it places the jobserver logic on a library;
- it removes sphinx/parallel-wrapper.sh;
- the code now properly implements a jobserver-aware logic
to do the parallelism when called via GNU make, failing back to
"-j" when there's no jobserver;
- converts check-variable-fonts.sh to Python and uses it via
function call;
- drops an extra script to generate man pages, adding a makefile
target for it;
- ensures that return code is 0 when PDF successfully builds;
- about half of the script is comments and documentation.
I tried to do my best to document all tricks that are inside the
script. This way, the docs build steps is now documented.
It should be noticed that it is out of the scope of this series
to change the implementation. Surely the process can be improved,
but first let's consolidate and document everything on a single
place.
Such script was written in a way that it can be called either
directly or via a Makefile. Running outside Makefile is
interesting specially when debug is needed. The command line
interface replaces the need of having lots of env vars before
calling sphinx-build:
$ ./tools/docs/sphinx-build-wrapper --help
usage: sphinx-build-wrapper [-h]
[--sphinxdirs SPHINXDIRS [SPHINXDIRS ...]] [--conf CONF]
[--builddir BUILDDIR] [--theme THEME] [--css CSS] [--paper {,a4,letter}] [-v]
[-j JOBS] [-i] [-V [VENV]]
{cleandocs,linkcheckdocs,htmldocs,epubdocs,texinfodocs,infodocs,mandocs,latexdocs,pdfdocs,xmldocs}
Kernel documentation builder
positional arguments:
{cleandocs,linkcheckdocs,htmldocs,epubdocs,texinfodocs,infodocs,mandocs,latexdocs,pdfdocs,xmldocs}
Documentation target to build
options:
-h, --help show this help message and exit
--sphinxdirs SPHINXDIRS [SPHINXDIRS ...]
Specific directories to build
--conf CONF Sphinx configuration file
--builddir BUILDDIR Sphinx configuration file
--theme THEME Sphinx theme to use
--css CSS Custom CSS file for HTML/EPUB
--paper {,a4,letter} Paper size for LaTeX/PDF output
-v, --verbose place build in verbose mode
-j, --jobs JOBS Sets number of jobs to use with sphinx-build
-i, --interactive Change latex default to run in interactive mode
-V, --venv [VENV] If used, run Sphinx from a venv dir (default dir: sphinx_latest)
the only mandatory argument is the target, which is identical with
"make" targets.
The call inside Makefile doesn't use the last four arguments. They're
there to help identifying problems at the build:
-v makes the output verbose;
-j helps to test parallelism;
-i runs latexmk in interactive mode, allowing to debug PDF
build issues;
-V is useful when testing it with different venvs.
When used with GNU make (or some other make which implements jobserver),
a call like:
make -j <targets> htmldocs
will make the wrapper to automatically use POSIX jobserver to claim
the number of available job slots, calling sphinx-build with a
"-j" parameter reflecting it. ON such case, the default can be
overriden via SPHINXDIRS argument.
Visiable changes when compared with the old behavior:
When V=0, the only visible difference is that:
- pdfdocs target now returns 0 on success, 1 on failures.
This addresses an issue over the current process where we
it always return success even on failures;
- it will now print the name of PDF files that failed to build,
if any.
In verbose mode, sphinx-build-wrapper and sphinx-build command lines
are now displayed.
- Bring the kernel memory-model docs into the Sphinx build in the "literal
include" mode.
- Lots of build-infrastructure work, further cleaning up long-term
kernel-doc technical debt. The sphinx-pre-install tool has been
converted to Python and updated for current systems.
- A new tool to detect when documents have been moved and generate HTML
redirects; this can be used on kernel.org (or any other site hosting the
rendered docs) to avoid breaking links.
- Automated processing of the YAML files describing the netlink protocol.
- A significant update of the maintainer's PGP guide.
...and a seemingly endless series of typo fixes, build-problem fixes, etc.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmjbwOoACgkQF0NaE2wM
flis1gf/ZvRi3Mo5hIsuGyQfs5kw/jx0N7SG4QYf2rEnt5ZGNa5SkyOVKsWQKTgK
LesQkdaCA0xHMoUWSvZRwn2a0+acpeMm6viXjewd2mU52sSNmSkKG4WsZyxfnOYS
36fkZ1qymQkJ4uSvx5NScTiIBqZx+Qfgkj0eNnXcpJd2vYeAVSu4szsFxeUvcJFj
Ckq3+3DQ5p/dcWwgvdlLKEJGj98Q3cqLrMn8ycbNtwzo3mdVbrlP5+qqNslZC6xY
Nqpv9HXbFWNCaL6YWCybcNOZ4F5UVno1ap2F3imTD8Rp1iG77zAQV5lMlq4Gksf4
kECLc1TtTKSgmgWHmi1sgudqM4Xqpw==
=Qe3Z
-----END PGP SIGNATURE-----
Merge tag 'docs-6.18' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"It has been a relatively busy cycle in docsland, with changes all
over:
- Bring the kernel memory-model docs into the Sphinx build in the
"literal include" mode.
- Lots of build-infrastructure work, further cleaning up long-term
kernel-doc technical debt. The sphinx-pre-install tool has been
converted to Python and updated for current systems.
- A new tool to detect when documents have been moved and generate
HTML redirects; this can be used on kernel.org (or any other site
hosting the rendered docs) to avoid breaking links.
- Automated processing of the YAML files describing the netlink
protocol.
- A significant update of the maintainer's PGP guide.
... and a seemingly endless series of typo fixes, build-problem fixes,
etc"
* tag 'docs-6.18' of git://git.lwn.net/linux: (193 commits)
Documentation/features: Update feature lists for 6.17-rc7
docs: remove cdomain.py
Documentation/process: submitting-patches: fix typo in "were do"
docs: dev-tools/lkmm: Fix typo of missing file extension
Documentation: trace: histogram: Convert ftrace docs cross-reference
Documentation: trace: histogram-design: Wrap introductory note in note:: directive
Documentation: trace: historgram-design: Separate sched_waking histogram section heading and the following diagram
Documentation: trace: histogram-design: Trim trailing vertices in diagram explanation text
Documentation: trace: histogram: Fix histogram trigger subsection number order
docs: driver-api: fix spelling of "buses".
Documentation: fbcon: Use admonition directives
Documentation: fbcon: Reindent 8th step of attach/detach/unload
Documentation: fbcon: Add boot options and attach/detach/unload section headings
docs: filesystems: sysfs: add remaining top level sysfs directory descriptions
docs: filesystems: sysfs: clarify symlink destinations in dev and bus/devices descriptions
docs: filesystems: sysfs: remove top level sysfs net directory
docs: maintainer: Fix ambiguous subheading formatting
docs: kdoc: a few more dump_typedef() tweaks
docs: kdoc: remove redundant comment stripping in dump_typedef()
docs: kdoc: remove some dead code in dump_typedef()
...
- Extend modules.builtin.modinfo to include module aliases from
MODULE_DEVICE_TABLE for builtin modules so that userspace tools (such
as kmod) can verify that a particular module alias will be handled by
a builtin module.
- Bump the minimum version of LLVM for building the kernel to 15.0.0.
- Upgrade several userspace API checks in headers_check.pl to errors.
- Unify and consolidate CONFIG_WERROR / W=e handling.
- Turn assembler and linker warnings into errors with CONFIG_WERROR /
W=e.
- Respect CONFIG_WERROR / W=e when building userspace programs
(userprogs).
- Enable -Werror unconditionally when building host programs
(hostprogs).
- Support copy_file_range() and data segment alignment in gen_init_cpio
to improve performance on filesystems that support reflinks such as
btrfs and XFS.
- Miscellaneous small changes to scripts and configuration files.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQR74yXHMTGczQHYypIdayaRccAalgUCaNrp6QAKCRAdayaRccAa
ljxRAP4hYocKXeWsiJzkTB199P4QUGWf220a9elBmtdJEed07gD/VBnCbSOxG3RO
vS8qbJHwxUFL7a+mDV8RIVXSt99NpAg=
=psG/
-----END PGP SIGNATURE-----
Merge tag 'kbuild-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux
Pull Kbuild updates from Nathan Chancellor:
- Extend modules.builtin.modinfo to include module aliases from
MODULE_DEVICE_TABLE for builtin modules so that userspace tools (such
as kmod) can verify that a particular module alias will be handled by
a builtin module
- Bump the minimum version of LLVM for building the kernel to 15.0.0
- Upgrade several userspace API checks in headers_check.pl to errors
- Unify and consolidate CONFIG_WERROR / W=e handling
- Turn assembler and linker warnings into errors with CONFIG_WERROR /
W=e
- Respect CONFIG_WERROR / W=e when building userspace programs
(userprogs)
- Enable -Werror unconditionally when building host programs
(hostprogs)
- Support copy_file_range() and data segment alignment in gen_init_cpio
to improve performance on filesystems that support reflinks such as
btrfs and XFS
- Miscellaneous small changes to scripts and configuration files
* tag 'kbuild-6.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux: (47 commits)
modpost: Initialize builtin_modname to stop SIGSEGVs
Documentation: kbuild: note CONFIG_DEBUG_EFI in reproducible builds
kbuild: vmlinux.unstripped should always depend on .vmlinux.export.o
modpost: Create modalias for builtin modules
modpost: Add modname to mod_device_table alias
scsi: Always define blogic_pci_tbl structure
kbuild: extract modules.builtin.modinfo from vmlinux.unstripped
kbuild: keep .modinfo section in vmlinux.unstripped
kbuild: always create intermediate vmlinux.unstripped
s390: vmlinux.lds.S: Reorder sections
KMSAN: Remove tautological checks
objtool: Drop noinstr hack for KCSAN_WEAK_MEMORY
lib/Kconfig.debug: Drop CLANG_VERSION check from DEBUG_INFO_DWARF_TOOLCHAIN_DEFAULT
riscv: Remove ld.lld version checks from many TOOLCHAIN_HAS configs
riscv: Unconditionally use linker relaxation
riscv: Remove version check for LTO_CLANG selects
powerpc: Drop unnecessary initializations in __copy_inst_from_kernel_nofault()
mips: Unconditionally select ARCH_HAS_CURRENT_STACK_POINTER
arm64: Remove tautological LLVM Kconfig conditions
ARM: Clean up definition of ARM_HAS_GROUP_RELOCS
...
- Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)
- lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
(Junjie Cao)
- Add str_assert_deassert() helper (Lad Prabhakar)
- gcc-plugins: Remove TODO_verify_il for GCC >= 16
- kconfig: Fix BrokenPipeError warnings in selftests
- kconfig: Add transitional symbol attribute for migration support
- kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCaNraNQAKCRA2KwveOeQk
u/DkAPwKPP5BSmVR2wkdpQaXIr3PGA+cbBYp34DMJNujZ9piIwD/WZ+HfGTLoERy
+2Q6HLj9hUdd+Rx3IZ8/w1QmnhUIUAU=
=AwV9
-----END PGP SIGNATURE-----
Merge tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening updates from Kees Cook:
"One notable addition is the creation of the 'transitional' keyword for
kconfig so CONFIG renaming can go more smoothly.
This has been a long-standing deficiency, and with the renaming of
CONFIG_CFI_CLANG to CONFIG_CFI (since GCC will soon have KCFI
support), this came up again.
The breadth of the diffstat is mainly this renaming.
- Clean up usage of TRAILING_OVERLAP() (Gustavo A. R. Silva)
- lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
(Junjie Cao)
- Add str_assert_deassert() helper (Lad Prabhakar)
- gcc-plugins: Remove TODO_verify_il for GCC >= 16
- kconfig: Fix BrokenPipeError warnings in selftests
- kconfig: Add transitional symbol attribute for migration support
- kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI"
* tag 'hardening-v6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
lib/string_choices: Add str_assert_deassert() helper
kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI
kconfig: Add transitional symbol attribute for migration support
kconfig: Fix BrokenPipeError warnings in selftests
gcc-plugins: Remove TODO_verify_il for GCC >= 16
stddef: Introduce __TRAILING_OVERLAP()
stddef: Remove token-pasting in TRAILING_OVERLAP()
lkdtm: fortify: Fix potential NULL dereference on kmalloc failure
This pattern isn't very documented, and apparently not used much outside
of 'make tools/help', but it has existed for over a decade (since commit
ea01fa9f63ae: "tools: Connect to the kernel build system").
However, it doesn't work very well for most cases, particularly the
useful "tools/all" target, because it overrides the LDFLAGS value with
an empty one.
And once overridden, 'make' will then not honor the tooling makefiles
trying to change it - which then makes any LDFLAGS use in the tooling
directory break, typically causing odd link errors.
Remove that LDFLAGS override, since it seems to be entirely historical.
The core kernel makefiles no longer modify LDFLAGS as part of the build,
and use kernel-specific link flags instead (eg 'KBUILD_LDFLAGS' and
friends).
This allows more of the 'make tools/*' cases to work. I say 'more',
because some of the tooling build rules make various other assumptions
or have other issues, so it's still a bit hit-or-miss. But those issues
tend to show up with the 'make -C tools xyz' pattern too, so now it's no
longer an issue of this particular 'tools/*' build rule being special.
Acked-by: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Borislav Petkov <bp@alien8.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel's CFI implementation uses the KCFI ABI specifically, and is
not strictly tied to a particular compiler. In preparation for GCC
supporting KCFI, rename CONFIG_CFI_CLANG to CONFIG_CFI (along with
associated options).
Use new "transitional" Kconfig option for old CONFIG_CFI_CLANG that will
enable CONFIG_CFI during olddefconfig.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://lore.kernel.org/r/20250923213422.1105654-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCgA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmjHMcoeHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG5bwH/23w8iGB4hf7L/7Z
e7blX42Pe9EXA1uK62iWmwEjDvBuJ7TmVfXH09qYJ56fj6/rJEdpQwtBMd4ypL81
QA/7lq5UEl0apPzMN86J8EHCzmjNzv7o+UtEd4C/hPFEZHZJa5Hqj9CBglSwSCEn
fTkLk7Gl6s8SfzBQ/rXX6/ZChAB/RleVWabDlIQMDz++/+9DZ0aqphj+5bYSqysL
ROQOaj4LOICuLfrup9J61hKNBoF7Dv3sO20vc+Iic0XHRPZ6/lKCnHgCUsqVIOOQ
L4kDT7XKQg+n3ttjrMe84/8iHZdWtf8VMWrtniPT8e1YGYuMpavVplgIcFoFCoNm
Qa7NPDs=
=rZeT
-----END PGP SIGNATURE-----
gpgsig -----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQR74yXHMTGczQHYypIdayaRccAalgUCaM3AYQAKCRAdayaRccAa
lkrsAQCfR0LymE8Hq+Vfk65DK4qZxigaXGTfg5n3xlPhTAh/iQEA02N0/ReHOOdH
nQde8709saIFE5axIMFvdWzbFPDtWwE=
=eIkf
-----END PGP SIGNATURE-----
Merge 6.17-rc6 into kbuild-next
Commit bd7c231212 ("pinctrl: meson: Fix typo in device table macro")
is needed in kbuild-next to avoid a build error with a future change.
While at it, address the conflict between commit 41f9049cff ("riscv:
Only allow LTO with CMODEL_MEDANY") and commit 6578a1ff6a ("riscv:
Remove version check for LTO_CLANG selects"), as reported by Stephen
Rothwell [1].
Link: https://lore.kernel.org/20250908134913.68778b7b@canb.auug.org.au/ [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Generating man files currently requires running a separate
script. The target also doesn't appear at the docs Makefile.
Add support for mandocs at the Makefile, adding the build
logic inside sphinx-build-wrapper, updating documentation
and dropping the ancillary script.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Message-ID: <3d248d724e7f3154f6e3a227e5923d7360201de9.1758196090.git.mchehab+huawei@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add a new script and a new documentation 'make' target,
htmldocs-redirects.
This will generate HTML stub files in the HTML documentation output
directory that redirect the browser to the new path.
Suggested-by: Konstantin Ryabitsev <konstantin@linuxfoundation.org>
Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <20250905144608.577449-4-vegard.nossum@oracle.com>
The duplication makes maintenance harder. Changes need to be done in two
places and the lines will grow overly long.
Use an intermediary variable instead.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20250813-kbuild-userprogs-bits-v1-1-2d9f7f411083@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Following commit e88ca24319 ("kbuild: consolidate warning flags
in scripts/Makefile.extrawarn"), move `-Dwarnings` handling into
`Makefile.extrawarn` like C's `-Werror`.
No functional change intended.
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: Nicolas Schier <nsc@kernel.org>
Link: https://lore.kernel.org/r/20250814-kbuild-werror-v2-3-c01e596309d2@linutronix.de
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
- Fix a shortcut key issue in menuconfig
- Fix missing rebuild of kheaders
- Sort the symbol dump generated by gendwarfsyms
- Support zboot extraction in scripts/extract-vmlinux
- Migrate gconfig to GTK 3
- Add TAR variable to allow overriding the default tar command
- Hand over Kbuild maintainership
-----BEGIN PGP SIGNATURE-----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=MtyJ
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
"This is the last pull request from me.
I'm grateful to have been able to continue as a maintainer for eight
years. From the next cycle, Nathan and Nicolas will maintain Kbuild.
- Fix a shortcut key issue in menuconfig
- Fix missing rebuild of kheaders
- Sort the symbol dump generated by gendwarfsyms
- Support zboot extraction in scripts/extract-vmlinux
- Migrate gconfig to GTK 3
- Add TAR variable to allow overriding the default tar command
- Hand over Kbuild maintainership"
* tag 'kbuild-v6.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (92 commits)
MAINTAINERS: hand over Kbuild maintenance
kheaders: make it possible to override TAR
kbuild: userprogs: use correct linker when mixing clang and GNU ld
kconfig: lxdialog: replace strcpy() with strncpy() in inputbox.c
kconfig: lxdialog: replace strcpy with snprintf in print_autowrap
kconfig: gconf: refactor text_insert_help()
kconfig: gconf: remove unneeded variable in text_insert_msg
kconfig: gconf: use hyphens in signals
kconfig: gconf: replace GtkImageMenuItem with GtkMenuItem
kconfig: gconf: Fix Back button behavior
kconfig: gconf: fix single view to display dependent symbols correctly
scripts: add zboot support to extract-vmlinux
gendwarfksyms: order -T symtypes output by name
gendwarfksyms: use preferred form of sizeof for allocation
kconfig: qconf: confine {begin,end}Group to constructor and destructor
kconfig: qconf: fix ConfigList::updateListAllforAll()
kconfig: add a function to dump all menu entries in a tree-like format
kconfig: gconf: show GTK version in About dialog
kconfig: gconf: replace GtkHPaned and GtkVPaned with GtkPaned
kconfig: gconf: replace GdkColor with GdkRGBA
...
Commit 86cdd2fdc4 ("kheaders: make headers archive reproducible")
introduced a number of options specific to GNU tar to the `tar`
invocation in `gen_kheaders.sh` script. This causes the script to fail
to work on systems where `tar` is not GNU tar. This can occur e.g.
on recent Gentoo Linux installations that support using bsdtar from
libarchive instead.
Add a `TAR` make variable to make it possible to override the tar
executable used, e.g. by specifying:
make TAR=gtar
Link: https://bugs.gentoo.org/884061
Reported-by: Sam James <sam@gentoo.org>
Tested-by: Sam James <sam@gentoo.org>
Co-developed-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Michał Górny <mgorny@gentoo.org>
Signed-off-by: Sam James <sam@gentoo.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The userprogs infrastructure does not expect clang being used with GNU ld
and in that case uses /usr/bin/ld for linking, not the configured $(LD).
This fallback is problematic as it will break when cross-compiling.
Mixing clang and GNU ld is used for example when building for SPARC64,
as ld.lld is not sufficient; see Documentation/kbuild/llvm.rst.
Relax the check around --ld-path so it gets used for all linkers.
Fixes: dfc1b168a8 ("kbuild: userprogs: use correct lld when linking through clang")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Toolchain and infrastructure:
- Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness',
'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and 'ref_as_ptr'.
These are intended to avoid type casts with the 'as' operator, which
are quite powerful, into restricted variants that are less powerful
and thus should help to avoid mistakes.
- Remove the 'author' key now that most instances were moved to the
plural one in the previous cycle.
'kernel' crate:
- New 'bug' module: add 'warn_on!' macro which reuses the existing
'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and
kernel parameters:
warn_on!(value == 42);
To avoid duplicating the assembly code, the same strategy is followed
as for the static branch code in order to share the assembly between
both C and Rust. This required a few rearrangements on C arch headers
-- the existing C macros should still generate the same outputs, thus
no functional change expected there.
- 'workqueue' module: add delayed work items, including a 'DelayedWork'
struct, a 'impl_has_delayed_work!' macro and an 'enqueue_delayed'
method, e.g.:
/// Enqueue the struct for execution on the system workqueue,
/// where its value will be printed 42 jiffies later.
fn print_later(value: Arc<MyStruct>) {
let _ = workqueue::system().enqueue_delayed(value, 42);
}
- New 'bits' module: add support for 'bit' and 'genmask' functions,
with runtime- and compile-time variants, e.g.:
static_assert!(0b00010000 == bit_u8(4));
static_assert!(0b00011110 == genmask_u8(1..=4));
assert!(checked_bit_u32(u32::BITS).is_none());
- 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which reads
NUL-terminated strings from userspace into a '&CStr'.
Introduce 'UserPtr' newtype, similar in purpose to '__user' in C, to
minimize mistakes handling userspace pointers, including mixing them
up with integers and leaking them via the 'Debug' trait. Add it to
the prelude, too.
- Start preparations for the replacement of our custom 'CStr' type
with the analogous type in the 'core' standard library. This will
take place across several cycles to make it easier. For this one,
it includes a new 'fmt' module, using upstream method names and some
other cleanups.
Replace 'fmt!' with a re-export, which helps Clippy lint properly,
and clean up the found 'uninlined-format-args' instances.
- 'dma' module:
- Clarify wording and be consistent in 'coherent' nomenclature.
- Convert the 'read!()' and 'write!()' macros to return a 'Result'.
- Add 'as_slice()', 'write()' methods in 'CoherentAllocation'.
- Expose 'count()' and 'size()' in 'CoherentAllocation' and add the
corresponding type invariants.
- Implement 'CoherentAllocation::dma_handle_with_offset()'.
- 'time' module:
- Make 'Instant' generic over clock source. This allows the compiler
to assert that arithmetic expressions involving the 'Instant' use
'Instants' based on the same clock source.
- Make 'HrTimer' generic over the timer mode. 'HrTimer' timers take a
'Duration' or an 'Instant' when setting the expiry time, depending
on the timer mode. With this change, the compiler can check the
type matches the timer mode.
- Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep
function that will select an appropriate sleep method depending on
the requested sleep time.
- Avoid 64-bit divisions on 32-bit hardware when calculating
timestamps.
- Seal the 'HrTimerMode' trait. This prevents users of the
'HrTimerMode' from implementing the trait on their own types.
- Pass the correct timer mode ID to 'hrtimer_start_range_ns()'.
- 'list' module: remove 'OFFSET' constants, allowing to remove pointer
arithmetic; now 'impl_list_item!' invokes 'impl_has_list_links!' or
'impl_has_list_links_self_ptr!'. Other simplifications too.
- 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a
constant, which avoids exposing the type of the opaque pointer, and
require 'into_foreign' to return non-null.
Remove the 'Either<L, R>' type as well. It is unused, and we want to
encourage the use of custom enums for concrete use cases.
- 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types
to allow them to be used in generic APIs.
- 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box<T, A>';
and 'Borrow', 'BorrowMut' and 'Default' for 'Vec<T, A>'.
- 'Opaque' type: add 'cast_from' method to perform a restricted cast
that cannot change the inner type and use it in callers of
'container_of!'. Rename 'raw_get' to 'cast_into' to match it.
- 'rbtree' module: add 'is_empty' method.
- 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and
'ARef', which are moved from the too general 'types' module which we
want to reduce or eventually remove. Also fix a safety comment in
'static_lock_class'.
'pin-init' crate:
- Add 'impl<T, E> [Pin]Init<T, E> for Result<T, E>', so results are now
(pin-)initializers.
- Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()'.
- New 'zeroed()', a safe version of 'mem::zeroed()' and also provide
it via 'Zeroable::zeroed()'.
- Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for
'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for '"Rust"'
and '"C"' ABIs and up to 20 arguments.
- Changed blanket impls of 'Init' and 'PinInit' from 'impl<T, E>
[Pin]Init<T, E> for T' to 'impl<T> [Pin]Init<T> for T'.
- Renamed 'zeroed()' to 'init_zeroed()'.
- Upstream dev news: improve CI more to deny warnings, use
'--all-targets'. Check the synchronization status of the two '-next'
branches in upstream and the kernel.
MAINTAINERS:
- Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo
Stoakes as reviewers (thanks everyone).
And a few other cleanups and improvements.
-----BEGIN PGP SIGNATURE-----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=5Wt9
-----END PGP SIGNATURE-----
Merge tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Enable a set of Clippy lints: 'ptr_as_ptr', 'ptr_cast_constness',
'as_ptr_cast_mut', 'as_underscore', 'cast_lossless' and
'ref_as_ptr'
These are intended to avoid type casts with the 'as' operator,
which are quite powerful, into restricted variants that are less
powerful and thus should help to avoid mistakes
- Remove the 'author' key now that most instances were moved to the
plural one in the previous cycle
'kernel' crate:
- New 'bug' module: add 'warn_on!' macro which reuses the existing
'BUG'/'WARN' infrastructure, i.e. it respects the usual sysctls and
kernel parameters:
warn_on!(value == 42);
To avoid duplicating the assembly code, the same strategy is
followed as for the static branch code in order to share the
assembly between both C and Rust
This required a few rearrangements on C arch headers -- the
existing C macros should still generate the same outputs, thus no
functional change expected there
- 'workqueue' module: add delayed work items, including a
'DelayedWork' struct, a 'impl_has_delayed_work!' macro and an
'enqueue_delayed' method, e.g.:
/// Enqueue the struct for execution on the system workqueue,
/// where its value will be printed 42 jiffies later.
fn print_later(value: Arc<MyStruct>) {
let _ = workqueue::system().enqueue_delayed(value, 42);
}
- New 'bits' module: add support for 'bit' and 'genmask' functions,
with runtime- and compile-time variants, e.g.:
static_assert!(0b00010000 == bit_u8(4));
static_assert!(0b00011110 == genmask_u8(1..=4));
assert!(checked_bit_u32(u32::BITS).is_none());
- 'uaccess' module: add 'UserSliceReader::strcpy_into_buf', which
reads NUL-terminated strings from userspace into a '&CStr'
Introduce 'UserPtr' newtype, similar in purpose to '__user' in C,
to minimize mistakes handling userspace pointers, including mixing
them up with integers and leaking them via the 'Debug' trait. Add
it to the prelude, too
- Start preparations for the replacement of our custom 'CStr' type
with the analogous type in the 'core' standard library. This will
take place across several cycles to make it easier. For this one,
it includes a new 'fmt' module, using upstream method names and
some other cleanups
Replace 'fmt!' with a re-export, which helps Clippy lint properly,
and clean up the found 'uninlined-format-args' instances
- 'dma' module:
- Clarify wording and be consistent in 'coherent' nomenclature
- Convert the 'read!()' and 'write!()' macros to return a 'Result'
- Add 'as_slice()', 'write()' methods in 'CoherentAllocation'
- Expose 'count()' and 'size()' in 'CoherentAllocation' and add
the corresponding type invariants
- Implement 'CoherentAllocation::dma_handle_with_offset()'
- 'time' module:
- Make 'Instant' generic over clock source. This allows the
compiler to assert that arithmetic expressions involving the
'Instant' use 'Instants' based on the same clock source
- Make 'HrTimer' generic over the timer mode. 'HrTimer' timers
take a 'Duration' or an 'Instant' when setting the expiry time,
depending on the timer mode. With this change, the compiler can
check the type matches the timer mode
- Add an abstraction for 'fsleep'. 'fsleep' is a flexible sleep
function that will select an appropriate sleep method depending
on the requested sleep time
- Avoid 64-bit divisions on 32-bit hardware when calculating
timestamps
- Seal the 'HrTimerMode' trait. This prevents users of the
'HrTimerMode' from implementing the trait on their own types
- Pass the correct timer mode ID to 'hrtimer_start_range_ns()'
- 'list' module: remove 'OFFSET' constants, allowing to remove
pointer arithmetic; now 'impl_list_item!' invokes
'impl_has_list_links!' or 'impl_has_list_links_self_ptr!'. Other
simplifications too
- 'types' module: remove 'ForeignOwnable::PointedTo' in favor of a
constant, which avoids exposing the type of the opaque pointer, and
require 'into_foreign' to return non-null
Remove the 'Either<L, R>' type as well. It is unused, and we want
to encourage the use of custom enums for concrete use cases
- 'sync' module: implement 'Borrow' and 'BorrowMut' for 'Arc' types
to allow them to be used in generic APIs
- 'alloc' module: implement 'Borrow' and 'BorrowMut' for 'Box<T, A>';
and 'Borrow', 'BorrowMut' and 'Default' for 'Vec<T, A>'
- 'Opaque' type: add 'cast_from' method to perform a restricted cast
that cannot change the inner type and use it in callers of
'container_of!'. Rename 'raw_get' to 'cast_into' to match it
- 'rbtree' module: add 'is_empty' method
- 'sync' module: new 'aref' submodule to hold 'AlwaysRefCounted' and
'ARef', which are moved from the too general 'types' module which
we want to reduce or eventually remove. Also fix a safety comment
in 'static_lock_class'
'pin-init' crate:
- Add 'impl<T, E> [Pin]Init<T, E> for Result<T, E>', so results are
now (pin-)initializers
- Add 'Zeroable::init_zeroed()' that delegates to 'init_zeroed()'
- New 'zeroed()', a safe version of 'mem::zeroed()' and also provide
it via 'Zeroable::zeroed()'
- Implement 'Zeroable' for 'Option<&T>', 'Option<&mut T>' and for
'Option<[unsafe] [extern "abi"] fn(...args...) -> ret>' for
'"Rust"' and '"C"' ABIs and up to 20 arguments
- Changed blanket impls of 'Init' and 'PinInit' from 'impl<T, E>
[Pin]Init<T, E> for T' to 'impl<T> [Pin]Init<T> for T'
- Renamed 'zeroed()' to 'init_zeroed()'
- Upstream dev news: improve CI more to deny warnings, use
'--all-targets'. Check the synchronization status of the two
'-next' branches in upstream and the kernel
MAINTAINERS:
- Add Vlastimil Babka, Liam R. Howlett, Uladzislau Rezki and Lorenzo
Stoakes as reviewers (thanks everyone)
And a few other cleanups and improvements"
* tag 'rust-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (76 commits)
rust: Add warn_on macro
arm64/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
riscv/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
x86/bug: Add ARCH_WARN_ASM macro for BUG/WARN asm code sharing with Rust
rust: kernel: move ARef and AlwaysRefCounted to sync::aref
rust: sync: fix safety comment for `static_lock_class`
rust: types: remove `Either<L, R>`
rust: kernel: use `core::ffi::CStr` method names
rust: str: add `CStr` methods matching `core::ffi::CStr`
rust: str: remove unnecessary qualification
rust: use `kernel::{fmt,prelude::fmt!}`
rust: kernel: add `fmt` module
rust: kernel: remove `fmt!`, fix clippy::uninlined-format-args
scripts: rust: emit path candidates in panic message
scripts: rust: replace length checks with match
rust: list: remove nonexistent generic parameter in link
rust: bits: add support for bits/genmask macros
rust: list: remove OFFSET constants
rust: list: add `impl_list_item!` examples
rust: list: use fully qualified path
...
- Introduce and start using TRAILING_OVERLAP() helper for fixing
embedded flex array instances (Gustavo A. R. Silva)
- mux: Convert mux_control_ops to a flex array member in mux_chip
(Thorsten Blum)
- string: Group str_has_prefix() and strstarts() (Andy Shevchenko)
- Remove KCOV instrumentation from __init and __head (Ritesh Harjani,
Kees Cook)
- Refactor and rename stackleak feature to support Clang
- Add KUnit test for seq_buf API
- Fix KUnit fortify test under LTO
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRSPkdeREjth1dHnSE2KwveOeQkuwUCaIfUkgAKCRA2KwveOeQk
uypLAP92r6f47sWcOw/5B9aVffX6Bypsb7dqBJQpCNxI5U1xcAEAiCrZ98UJyOeQ
JQgnXd4N67K4EsS2JDc+FutRn3Yi+A8=
=+5Bq
-----END PGP SIGNATURE-----
Merge tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull hardening updates from Kees Cook:
- Introduce and start using TRAILING_OVERLAP() helper for fixing
embedded flex array instances (Gustavo A. R. Silva)
- mux: Convert mux_control_ops to a flex array member in mux_chip
(Thorsten Blum)
- string: Group str_has_prefix() and strstarts() (Andy Shevchenko)
- Remove KCOV instrumentation from __init and __head (Ritesh Harjani,
Kees Cook)
- Refactor and rename stackleak feature to support Clang
- Add KUnit test for seq_buf API
- Fix KUnit fortify test under LTO
* tag 'hardening-v6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (22 commits)
sched/task_stack: Add missing const qualifier to end_of_stack()
kstack_erase: Support Clang stack depth tracking
kstack_erase: Add -mgeneral-regs-only to silence Clang warnings
init.h: Disable sanitizer coverage for __init and __head
kstack_erase: Disable kstack_erase for all of arm compressed boot code
x86: Handle KCOV __init vs inline mismatches
arm64: Handle KCOV __init vs inline mismatches
s390: Handle KCOV __init vs inline mismatches
arm: Handle KCOV __init vs inline mismatches
mips: Handle KCOV __init vs inline mismatch
powerpc/mm/book3s64: Move kfence and debug_pagealloc related calls to __init section
configs/hardening: Enable CONFIG_INIT_ON_FREE_DEFAULT_ON
configs/hardening: Enable CONFIG_KSTACK_ERASE
stackleak: Split KSTACK_ERASE_CFLAGS from GCC_PLUGINS_CFLAGS
stackleak: Rename stackleak_track_stack to __sanitizer_cov_stack_depth
stackleak: Rename STACKLEAK to KSTACK_ERASE
seq_buf: Introduce KUnit tests
string: Group str_has_prefix() and strstarts()
kunit/fortify: Add back "volatile" for sizeof() constants
acpi: nfit: intel: avoid multiple -Wflex-array-member-not-at-end warnings
...
In preparation for Clang stack depth tracking for KSTACK_ERASE,
split the stackleak-specific cflags out of GCC_PLUGINS_CFLAGS into
KSTACK_ERASE_CFLAGS.
Link: https://lore.kernel.org/r/20250717232519.2984886-3-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
In Rust 1.78.0, Clippy introduced the `ref_as_ptr` lint [1]:
> Using `as` casts may result in silently changing mutability or type.
While this doesn't eliminate unchecked `as` conversions, it makes such
conversions easier to scrutinize. It also has the slight benefit of
removing a degree of freedom on which to bikeshed. Thus apply the
changes and enable the lint -- no functional change intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#ref_as_ptr [1]
Suggested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/all/D8PGG7NTWB6U.3SS3A5LN4XWMN@proton.me/
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-6-f43b024581e8@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Before Rust 1.29.0, Clippy introduced the `cast_lossless` lint [1]:
> Rust’s `as` keyword will perform many kinds of conversions, including
> silently lossy conversions. Conversion functions such as `i32::from`
> will only perform lossless conversions. Using the conversion functions
> prevents conversions from becoming silently lossy if the input types
> ever change, and makes it clear for people reading the code that the
> conversion is lossless.
While this doesn't eliminate unchecked `as` conversions, it makes such
conversions easier to scrutinize. It also has the slight benefit of
removing a degree of freedom on which to bikeshed. Thus apply the
changes and enable the lint -- no functional change intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#cast_lossless [1]
Suggested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/all/D8ORTXSUTKGL.1KOJAGBM8F8TN@proton.me/
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Acked-by: Jocelyn Falempe <jfalempe@redhat.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-5-f43b024581e8@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In Rust 1.63.0, Clippy introduced the `as_underscore` lint [1]:
> The conversion might include lossy conversion or a dangerous cast that
> might go undetected due to the type being inferred.
>
> The lint is allowed by default as using `_` is less wordy than always
> specifying the type.
Always specifying the type is especially helpful in function call
contexts where the inferred type may change at a distance. Specifying
the type also allows Clippy to spot more cases of `useless_conversion`.
The primary downside is the need to specify the type in trivial getters.
There are 4 such functions: 3 have become slightly less ergonomic, 1 was
revealed to be a `useless_conversion`.
While this doesn't eliminate unchecked `as` conversions, it makes such
conversions easier to scrutinize. It also has the slight benefit of
removing a degree of freedom on which to bikeshed. Thus apply the
changes and enable the lint -- no functional change intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#as_underscore [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-4-f43b024581e8@gmail.com
[ Changed `isize` to `c_long`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In Rust 1.66.0, Clippy introduced the `as_ptr_cast_mut` lint [1]:
> Since `as_ptr` takes a `&self`, the pointer won’t have write
> permissions unless interior mutability is used, making it unlikely
> that having it as a mutable pointer is correct.
There is only one affected callsite, and the change amounts to replacing
`as _` with `.cast_mut().cast()`. This doesn't change the semantics, but
is more descriptive of what's going on.
Apply this change and enable the lint -- no functional change intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#as_ptr_cast_mut [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-3-f43b024581e8@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In Rust 1.72.0, Clippy introduced the `ptr_cast_constness` lint [1]:
> Though `as` casts between raw pointers are not terrible,
> `pointer::cast_mut` and `pointer::cast_const` are safer because they
> cannot accidentally cast the pointer to another type.
There are only 3 affected sites:
- `*mut T as *const U as *mut U` becomes `(*mut T).cast()`.
- `&self as *const Self as *mut Self` becomes
`core::ptr::from_ref(self).cast_mut()`.
- `*const T as *mut _` becommes `(*const T).cast_mut()`.
Apply these changes and enable the lint -- no functional change
intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_cast_constness [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-2-f43b024581e8@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
In Rust 1.51.0, Clippy introduced the `ptr_as_ptr` lint [1]:
> Though `as` casts between raw pointers are not terrible,
> `pointer::cast` is safer because it cannot accidentally change the
> pointer's mutability, nor cast the pointer to other types like `usize`.
There are a few classes of changes required:
- Modules generated by bindgen are marked
`#[allow(clippy::ptr_as_ptr)]`.
- Inferred casts (` as _`) are replaced with `.cast()`.
- Ascribed casts (` as *... T`) are replaced with `.cast::<T>()`.
- Multistep casts from references (` as *const _ as *const T`) are
replaced with `core::ptr::from_ref(&x).cast()` with or without `::<T>`
according to the previous rules. The `core::ptr::from_ref` call is
required because `(x as *const _).cast::<T>()` results in inference
failure.
- Native literal C strings are replaced with `c_str!().as_char_ptr()`.
- `*mut *mut T as _` is replaced with `let *mut *const T = (*mut *mut
T)`.cast();` since pointer to pointer can be confusing.
Apply these changes and enable the lint -- no functional change
intended.
Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_as_ptr [1]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-1-f43b024581e8@gmail.com
[ Added `.cast()` for `opp`. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
- Add support for the EXPORT_SYMBOL_GPL_FOR_MODULES() macro, which exports a
symbol only to specified modules
- Improve ABI handling in gendwarfksyms
- Forcibly link lib-y objects to vmlinux even if CONFIG_MODULES=n
- Add checkers for redundant or missing <linux/export.h> inclusion
- Deprecate the extra-y syntax
- Fix a genksyms bug when including enum constants from *.symref files
-----BEGIN PGP SIGNATURE-----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=Dy49
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Add support for the EXPORT_SYMBOL_GPL_FOR_MODULES() macro, which
exports a symbol only to specified modules
- Improve ABI handling in gendwarfksyms
- Forcibly link lib-y objects to vmlinux even if CONFIG_MODULES=n
- Add checkers for redundant or missing <linux/export.h> inclusion
- Deprecate the extra-y syntax
- Fix a genksyms bug when including enum constants from *.symref files
* tag 'kbuild-v6.16' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (28 commits)
genksyms: Fix enum consts from a reference affecting new values
arch: use always-$(KBUILD_BUILTIN) for vmlinux.lds
kbuild: set y instead of 1 to KBUILD_{BUILTIN,MODULES}
efi/libstub: use 'targets' instead of extra-y in Makefile
module: make __mod_device_table__* symbols static
scripts/misc-check: check unnecessary #include <linux/export.h> when W=1
scripts/misc-check: check missing #include <linux/export.h> when W=1
scripts/misc-check: add double-quotes to satisfy shellcheck
kbuild: move W=1 check for scripts/misc-check to top-level Makefile
scripts/tags.sh: allow to use alternative ctags implementation
kconfig: introduce menu type enum
docs: symbol-namespaces: fix reST warning with literal block
kbuild: link lib-y objects to vmlinux forcibly even when CONFIG_MODULES=n
tinyconfig: enable CONFIG_LD_DEAD_CODE_DATA_ELIMINATION
docs/core-api/symbol-namespaces: drop table of contents and section numbering
modpost: check forbidden MODULE_IMPORT_NS("module:") at compile time
kbuild: move kbuild syntax processing to scripts/Makefile.build
Makefile: remove dependency on archscripts for header installation
Documentation/kbuild: Add new gendwarfksyms kABI rules
Documentation/kbuild: Drop section numbers
...
KBUILD_BUILTIN is set to 1 unless you are building only modules.
KBUILD_MODULES is set to 1 when you are building only modules
(a typical use case is "make modules").
It is more useful to set them to 'y' instead, so we can do
something like:
always-$(KBUILD_BUILTIN) += vmlinux.lds
This works equivalently to:
extra-y += vmlinux.lds
This allows us to deprecate extra-y. extra-y and always-y are quite
similar, and we do not need both.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
This script is executed only when ${KBUILD_EXTRA_WARN} contains 1.
Move this check to the top-level Makefile to allow more checks to be
easily added to this script.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Since commit 7273ad2b08 ("kbuild: link lib-y objects to vmlinux
forcibly when CONFIG_MODULES=y"), all objects from lib-y have been
forcibly linked to vmlinux when CONFIG_MODULES=y.
To simplify future changes, this commit makes all objects from lib-y
be linked regardless of the CONFIG_MODULES setting.
Most use cases (CONFIG_MODULES=y) are not affected by this change.
The vmlinux size with ARCH=arm allnoconfig, where CONFIG_MODULES=n,
increases as follows:
text data bss dec hex filename
1368644 835104 206288 2410036 24c634 vmlinux.before
1379440 837064 206288 2422792 24f808 vmlinux.after
We no longer benefit from using static libraries, but the impact is
mitigated by supporting CONFIG_LD_DEAD_CODE_DATA_ELIMINATION.
For example, the size of vmlinux remains almost the same with ARCH=arm
tinyconfig, where CONFIG_MODULES=n and
CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y.
text data bss dec hex filename
455316 93404 15472 564192 89be0 vmlinux.before
455312 93404 15472 564188 89bdc vmlinux.after
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
- The most significant change is the replacement of the old kernel-doc
script (a monstrous collection of Perl regexes that predates the Git era)
with a Python reimplementation. That, too, is a horrifying collection of
regexes, but in a much cleaner and more maintainable structure that
integrates far better with the Sphinx build system.
This change has been in linux-next for the full 6.15 cycle; the small
number of problems that turned up have been addressed, seemingly to
everybody's satisfaction. The Perl kernel-doc script remains in tree (as
scripts/kernel-doc.pl) and can be used with a command-line option if need
be. Unless some reason to keep it around materializes, it will probably
go away in 6.17.
Credit goes to Mauro Carvalho Chehab for doing all this work.
- Some RTLA documentation updates
- A handful of Chinese translations
- The usual collection of typo fixes, general updates, etc.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmg0j/IPHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5Yu7sH/1w2LtO8XB/KTRNmuz3tV6KzGtDvQVwqgxB2
X8bbeJlBtYenvuak66RjCfucOh7Y8Ni3UN0G2BGa67KBAxmZEYc6u+IF4SrJUg5g
DuS6+ZXgqV4TrjWMRof5LtPS8KbNJLGnqgxSVdEPSBV0jJ13r3gb3/e7X06iNAKR
X4Nq+h5aa1tCwZTkPOSHHQn4qm3Tb1LQreDSn8gnBn6e8nVJIakNlwaVYkClhI9B
byvItInv32LPAXPDkcEWITvLNUTiMobTyfBYHOD6i3nImQ+j4ZiMMmOUjiB+0jDO
UQDvoUa46ipXkLBsBOrYEkM/iKXBawMwTa3CcudxR4scvVgATJs=
=BQ9X
-----END PGP SIGNATURE-----
Merge tag 'docs-6.16' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"A moderately busy cycle for documentation this time around:
- The most significant change is the replacement of the old
kernel-doc script (a monstrous collection of Perl regexes that
predates the Git era) with a Python reimplementation. That, too, is
a horrifying collection of regexes, but in a much cleaner and more
maintainable structure that integrates far better with the Sphinx
build system.
This change has been in linux-next for the full 6.15 cycle; the
small number of problems that turned up have been addressed,
seemingly to everybody's satisfaction. The Perl kernel-doc script
remains in tree (as scripts/kernel-doc.pl) and can be used with a
command-line option if need be. Unless some reason to keep it
around materializes, it will probably go away in 6.17.
Credit goes to Mauro Carvalho Chehab for doing all this work.
- Some RTLA documentation updates
- A handful of Chinese translations
- The usual collection of typo fixes, general updates, etc"
* tag 'docs-6.16' of git://git.lwn.net/linux: (85 commits)
Docs: doc-guide: update sphinx.rst Sphinx version number
docs: doc-guide: clarify latest theme usage
Documentation/scheduler: Fix typo in sched-stats domain field description
scripts: kernel-doc: prevent a KeyError when checking output
docs: kerneldoc.py: simplify exception handling logic
MAINTAINERS: update linux-doc entry to cover new Python scripts
docs: align with scripts/syscall.tbl migration
Documentation: NTB: Fix typo
Documentation: ioctl-number: Update table intro
docs: conf.py: drop backward support for old Sphinx versions
Docs: driver-api/basics: add kobject_event interfaces
Docs: relay: editing cleanups
docs: fix "incase" typo in coresight/panic.rst
Fix spelling error for 'parallel'
docs: admin-guide: fix typos in reporting-issues.rst
docs: dmaengine: add explanation for DMA_ASYNC_TX capability
Documentation: leds: improve readibility of multicolor doc
docs: fix typo in firmware-related section
docs: Makefile: Inherit PYTHONPYCACHEPREFIX setting as env variable
Documentation: ioctl-number: Update outdated submission info
...
archscripts has nothing to do with headers_install.
Signed-off-by: Henrik Lindström <henrik@lxm.se>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This reverts commit dbdffaf50f.
--remap-path-prefix breaks the ability of debuggers to find the source
file corresponding to object files. As there is no simple or uniform
way to specify the source directory explicitly, this breaks developers
workflows.
Revert the unconditional usage of --remap-path-prefix, equivalent to the
same change for -ffile-prefix-map in KBUILD_CPPFLAGS.
Fixes: dbdffaf50f ("kbuild, rust: use -fremap-path-prefix to make paths relative")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This reverts commit cacd22ce69.
-ffile-prefix-map breaks the ability of debuggers to find the source
file corresponding to object files. As there is no simple or uniform
way to specify the source directory explicitly, this breaks developers
workflows.
Revert the unconditional usage of -ffile-prefix-map.
Reported-by: Matthieu Baerts <matttbe@kernel.org>
Closes: https://lore.kernel.org/lkml/edc50aa7-0740-4942-8c15-96f12f2acc7e@kernel.org/
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Closes: https://lore.kernel.org/lkml/aBEttQH4kimHFScx@intel.com/
Fixes: cacd22ce69 ("kbuild: make all file references relative to source root")
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Clang and GCC have different behaviors around disabling warnings
included in -Wall and -Wextra and the order in which flags are
specified, which is exposed by clang's new support for
-Wunterminated-string-initialization.
$ cat test.c
const char foo[3] = "FOO";
const char bar[3] __attribute__((__nonstring__)) = "BAR";
$ clang -fsyntax-only -Wextra test.c
test.c:1:21: warning: initializer-string for character array is too long, array size is 3 but initializer has size 4 (including the null terminating character); did you mean to use the 'nonstring' attribute? [-Wunterminated-string-initialization]
1 | const char foo[3] = "FOO";
| ^~~~~
$ clang -fsyntax-only -Wextra -Wno-unterminated-string-initialization test.c
$ clang -fsyntax-only -Wno-unterminated-string-initialization -Wextra test.c
test.c:1:21: warning: initializer-string for character array is too long, array size is 3 but initializer has size 4 (including the null terminating character); did you mean to use the 'nonstring' attribute? [-Wunterminated-string-initialization]
1 | const char foo[3] = "FOO";
| ^~~~~
$ gcc -fsyntax-only -Wextra test.c
test.c:1:21: warning: initializer-string for array of ‘char’ truncates NUL terminator but destination lacks ‘nonstring’ attribute (4 chars into 3 available) [-Wunterminated-string-initialization]
1 | const char foo[3] = "FOO";
| ^~~~~
$ gcc -fsyntax-only -Wextra -Wno-unterminated-string-initialization test.c
$ gcc -fsyntax-only -Wno-unterminated-string-initialization -Wextra test.c
Move -Wextra up right below -Wall in Makefile.extrawarn to ensure these
flags are at the beginning of the warning options list. Move the couple
of warning options that have been added to the main Makefile since
commit e88ca24319 ("kbuild: consolidate warning flags in
scripts/Makefile.extrawarn") to scripts/Makefile.extrawarn after -Wall /
-Wextra to ensure they get properly disabled for all compilers.
Fixes: 9d7a0577c9 ("gcc-15: disable '-Wunterminated-string-initialization' entirely for now")
Link: https://github.com/llvm/llvm-project/issues/10359
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As kernel-doc script is used not only on Documentation, but
also on scripts and drivers/drm Makefiles, move it to the
main makefile, as otherwise sub-makefiles may not have it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Tested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Message-ID: <bb3ea3b49e76aee51dae7762db10c4d38cd67afe.1745453655.git.mchehab+huawei@kernel.org>
This was triggered by one of my mis-uses causing odd build warnings on
sparc in linux-next, but while figuring out why the "obviously correct"
use of cc-option caused such odd breakage, I found eight other cases of
the same thing in the tree.
The root cause is that 'cc-option' doesn't work for checking negative
warning options (ie things like '-Wno-stringop-overflow') because gcc
will silently accept options it doesn't recognize, and so 'cc-option'
ends up thinking they are perfectly fine.
And it all works, until you have a situation where _another_ warning is
emitted. At that point the compiler will go "Hmm, maybe the user
intended to disable this warning but used that wrong option that I
didn't recognize", and generate a warning for the unrecognized negative
option.
Which explains why we have several cases of this in the tree: the
'cc-option' test really doesn't work for this situation, but most of the
time it simply doesn't matter that ity doesn't work.
The reason my recently added case caused problems on sparc was pointed
out by Thomas Weißschuh: the sparc build had a previous explicit warning
that then triggered the new one.
I think the best fix for this would be to make 'cc-option' a bit smarter
about this sitation, possibly by adding an intentional warning to the
test case that then triggers the unrecognized option warning reliably.
But the short-term fix is to replace 'cc-option' with an existing helper
designed for this exact case: 'cc-disable-warning', which picks the
negative warning but uses the positive form for testing the compiler
support.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/all/20250422204718.0b4e3f81@canb.auug.org.au/
Explained-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I had left the warning around but as a non-fatal error to get my gcc-15
builds going, but fixed up some of the most annoying warning cases so
that it wouldn't be *too* verbose.
Because I like the _concept_ of the warning, even if I detested the
implementation to shut it up.
It turns out the implementation to shut it up is even more broken than I
thought, and my "shut up most of the warnings" patch just caused fatal
errors on gcc-14 instead.
I had tested with clang, but when I upgrade my development environment,
I try to do it on all machines because I hate having different systems
to maintain, and hadn't realized that gcc-14 now had issues.
The ACPI case is literally why I wanted to have a *type* that doesn't
trigger the warning (see commit d5d45a7f2619: "gcc-15: make
'unterminated string initialization' just a warning"), instead of
marking individual places as "__nonstring".
But gcc-14 doesn't like that __nonstring location that shut gcc-15 up,
because it's on an array of char arrays, not on one single array:
drivers/acpi/tables.c:399:1: error: 'nonstring' attribute ignored on objects of type 'const char[][4]' [-Werror=attributes]
399 | static const char table_sigs[][ACPI_NAMESEG_SIZE] __initconst __nonstring = {
| ^~~~~~
and my attempts to nest it properly with a type had failed, because of
how gcc doesn't like marking the types as having attributes, only
symbols.
There may be some trick to it, but I was already annoyed by the bad
attribute design, now I'm just entirely fed up with it.
I wish gcc had a proper way to say "this type is a *byte* array, not a
string".
The obvious thing would be to distinguish between "char []" and an
explicitly signed "unsigned char []" (as opposed to an implicitly
unsigned char, which is typically an architecture-specific default, but
for the kernel is universal thanks to '-funsigned-char').
But any "we can typedef a 8-bit type to not become a string just because
it's an array" model would be fine.
But "__attribute__((nonstring))" is sadly not that sane model.
Reported-by: Chris Clayton <chris2553@googlemail.com>
Fixes: 4b4bd8c50f ("gcc-15: acpi: sprinkle random '__nonstring' crumbles around")
Fixes: d5d45a7f26 ("gcc-15: make 'unterminated string initialization' just a warning")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
gcc-15 enabling -Wunterminated-string-initialization in -Wextra by
default was done with the best intentions, but the warning is still
quite broken.
What annoys me about the warning is that this is a very traditional AND
CORRECT way to initialize fixed byte arrays in C:
unsigned char hex[16] = "0123456789abcdef";
and we use this all over the kernel. And the warning is fine, but gcc
developers apparently never made a reasonable way to disable it. As is
(sadly) tradition with these things.
Yes, there's "__attribute__((nonstring))", and we have a macro to make
that absolutely disgusting syntax more palatable (ie the kernel syntax
for that monstrosity is just "__nonstring").
But that attribute is misdesigned. What you'd typically want to do is
tell the compiler that you are using a type that isn't a string but a
byte array, but that doesn't work at all:
warning: ‘nonstring’ attribute does not apply to types [-Wattributes]
and because of this fundamental mis-design, you then have to mark each
instance of that pattern.
This is particularly noticeable in our ACPI code, because ACPI has this
notion of a 4-byte "type name" that gets used all over, and is exactly
this kind of byte array.
This is a sad oversight, because the warning is useful, but really would
be so much better if gcc had also given a sane way to indicate that we
really just want a byte array type at a type level, not the broken "each
and every array definition" level.
So now instead of creating a nice "ACPI name" type using something like
typedef char acpi_name_t[4] __nonstring;
we have to do things like
char name[ACPI_NAMESEG_SIZE] __nonstring;
in every place that uses this concept and then happens to have the
typical initializers.
This is annoying me mainly because I think the warning _is_ a good
warning, which is why I'm not just turning it off in disgust. But it is
hampered by this bad implementation detail.
[ And obviously I'm doing this now because system upgrades for me are
something that happen in the middle of the release cycle: don't do it
before or during travel, or just before or during the busy merge
window period. ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Toolchain and infrastructure:
- Fix missing KASAN LLVM flags on first build (and fix spurious
rebuilds) by skipping '--target'.
- Fix Make < 4.3 build error by using '$(pound)'.
- Fix UML build error by removing 'volatile' qualifier from io helpers.
- Fix UML build error by adding 'dma_{alloc,free}_attrs()' helpers.
- Clean gendwarfksyms warnings by avoiding to export '__pfx' symbols.
- Clean objtool warning by adding a new 'noreturn' function for 1.86.0.
- Disable 'needless_continue' Clippy lint due to new 1.86.0 warnings.
- Add missing 'ffi' crate to 'generate_rust_analyzer.py'.
'pin-init' crate:
- Import a couple fixes from upstream.
-----BEGIN PGP SIGNATURE-----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=fm2H
-----END PGP SIGNATURE-----
Merge tag 'rust-fixes-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull rust fixes from Miguel Ojeda:
"Toolchain and infrastructure:
- Fix missing KASAN LLVM flags on first build (and fix spurious
rebuilds) by skipping '--target'
- Fix Make < 4.3 build error by using '$(pound)'
- Fix UML build error by removing 'volatile' qualifier from io
helpers
- Fix UML build error by adding 'dma_{alloc,free}_attrs()' helpers
- Clean gendwarfksyms warnings by avoiding to export '__pfx' symbols
- Clean objtool warning by adding a new 'noreturn' function for
1.86.0
- Disable 'needless_continue' Clippy lint due to new 1.86.0 warnings
- Add missing 'ffi' crate to 'generate_rust_analyzer.py'
'pin-init' crate:
- Import a couple fixes from upstream"
* tag 'rust-fixes-6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
rust: helpers: Add dma_alloc_attrs() and dma_free_attrs()
rust: helpers: Remove volatile qualifier from io helpers
rust: kbuild: use `pound` to support GNU Make < 4.3
objtool/rust: add one more `noreturn` Rust function for Rust 1.86.0
rust: kasan/kbuild: fix missing flags on first build
rust: disable `clippy::needless_continue`
rust: kbuild: Don't export __pfx symbols
rust: pin-init: use Markdown autolinks in Rust comments
rust: pin-init: alloc: restrict `impl ZeroableOption` for `Box` to `T: Sized`
scripts: generate_rust_analyzer: Add ffi crate
Starting with Rust 1.86.0, Clippy's `needless_continue` lint complains
about the last statement of a loop [1], including cases like:
while ... {
match ... {
... if ... => {
...
return ...;
}
_ => continue,
}
}
as well as nested `match`es in a loop.
One solution is changing `continue` for `()` [2], but arguably using
`continue` shows the intent better when it is alone in an arm like that.
Moreover, I am not sure we want to force people to try to find other
ways to write the code either, in cases when that applies.
In addition, the help text does not really apply in the new cases the
lint has introduced, e.g. here one cannot simply "drop" the expression:
warning: this `continue` expression is redundant
--> rust/macros/helpers.rs:85:18
|
85 | _ => continue,
| ^^^^^^^^
|
= help: consider dropping the `continue` expression
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_continue
= note: requested on the command line with `-W clippy::needless-continue`
The examples in the documentation do not show a case like this, either,
so the second "help" line does not help.
In addition, locally disabling the lint is not possible with `expect`,
since the behavior differs across versions. Using `allow` would be
possible, but, even then, an extra line just for this is a bit too much,
especially if there are other ways to satisfy the lint.
Finally, the lint is still in the "pedantic" category and disabled by
default by Clippy.
Thus disable the lint, at least for the time being.
Feedback was submitted to upstream Clippy, in case this can be improved
or perhaps the lint split into several [3].
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust-clippy/pull/13891 [1]
Link: https://lore.kernel.org/rust-for-linux/20250401221205.52381-1-ojeda@kernel.org/ [2]
Link: https://github.com/rust-lang/rust-clippy/issues/14536 [3]
Link: https://lore.kernel.org/r/20250403163805.67770-1-ojeda@kernel.org
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
A recent optimization change in LLVM [1] aims to transform certain loop
idioms into calls to strlen() or wcslen(). This change transforms the
first while loop in UniStrcat() into a call to wcslen(), breaking the
build when UniStrcat() gets inlined into alloc_path_with_tree_prefix():
ld.lld: error: undefined symbol: wcslen
>>> referenced by nls_ucs2_utils.h:54 (fs/smb/client/../../nls/nls_ucs2_utils.h:54)
>>> vmlinux.o:(alloc_path_with_tree_prefix)
>>> referenced by nls_ucs2_utils.h:54 (fs/smb/client/../../nls/nls_ucs2_utils.h:54)
>>> vmlinux.o:(alloc_path_with_tree_prefix)
Disable this optimization with '-fno-builtin-wcslen', which prevents the
compiler from assuming that wcslen() is available in the kernel's C
library.
[ More to the point - it's not that we couldn't implement wcslen(), it's
that this isn't an optimization at all in the context of the kernel.
Replacing a simple inlined loop with a function call to the same loop
is just stupid and pointless if you don't have long strings and fancy
libraries with vectorization support etc.
For the regular 'strlen()' cases, we want the compiler to do this in
order to handle the trivial case of constant strings. And we do have
optimized versions of 'strlen()' on some architectures. But for
wcslen? Just no. - Linus ]
Cc: stable@vger.kernel.org
Link: 9694844d7e [1]
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Improve performance in gendwarfksyms
- Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS
- Support CONFIG_HEADERS_INSTALL for ARCH=um
- Use more relative paths to sources files for better reproducibility
- Support the loong64 Debian architecture
- Add Kbuild bash completion
- Introduce intermediate vmlinux.unstripped for architectures that need
static relocations to be stripped from the final vmlinux
- Fix versioning in Debian packages for -rc releases
- Treat missing MODULE_DESCRIPTION() as an error
- Convert Nios2 Makefiles to use the generic rule for built-in DTB
- Add debuginfo support to the RPM package
-----BEGIN PGP SIGNATURE-----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=GiQ6
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Improve performance in gendwarfksyms
- Remove deprecated EXTRA_*FLAGS and KBUILD_ENABLE_EXTRA_GCC_CHECKS
- Support CONFIG_HEADERS_INSTALL for ARCH=um
- Use more relative paths to sources files for better reproducibility
- Support the loong64 Debian architecture
- Add Kbuild bash completion
- Introduce intermediate vmlinux.unstripped for architectures that need
static relocations to be stripped from the final vmlinux
- Fix versioning in Debian packages for -rc releases
- Treat missing MODULE_DESCRIPTION() as an error
- Convert Nios2 Makefiles to use the generic rule for built-in DTB
- Add debuginfo support to the RPM package
* tag 'kbuild-v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (40 commits)
kbuild: rpm-pkg: build a debuginfo RPM
kconfig: merge_config: use an empty file as initfile
nios2: migrate to the generic rule for built-in DTB
rust: kbuild: skip `--remap-path-prefix` for `rustdoc`
kbuild: pacman-pkg: hardcode module installation path
kbuild: deb-pkg: don't set KBUILD_BUILD_VERSION unconditionally
modpost: require a MODULE_DESCRIPTION()
kbuild: make all file references relative to source root
x86: drop unnecessary prefix map configuration
kbuild: deb-pkg: add comment about future removal of KDEB_COMPRESS
kbuild: Add a help message for "headers"
kbuild: deb-pkg: remove "version" variable in mkdebian
kbuild: deb-pkg: fix versioning for -rc releases
Documentation/kbuild: Fix indentation in modules.rst example
x86: Get rid of Makefile.postlink
kbuild: Create intermediate vmlinux build with relocations preserved
kbuild: Introduce Kconfig symbol for linking vmlinux with relocations
kbuild: link-vmlinux.sh: Make output file name configurable
kbuild: do not generate .tmp_vmlinux*.map when CONFIG_VMLINUX_MAP=y
Revert "kheaders: Ignore silly-rename files"
...
two locking commits in the locking tree,
part of the locking-core-2025-03-22 pull request. ]
x86 CPU features support:
- Generate the <asm/cpufeaturemasks.h> header based on build config
(H. Peter Anvin, Xin Li)
- x86 CPUID parsing updates and fixes (Ahmed S. Darwish)
- Introduce the 'setcpuid=' boot parameter (Brendan Jackman)
- Enable modifying CPU bug flags with '{clear,set}puid='
(Brendan Jackman)
- Utilize CPU-type for CPU matching (Pawan Gupta)
- Warn about unmet CPU feature dependencies (Sohil Mehta)
- Prepare for new Intel Family numbers (Sohil Mehta)
Percpu code:
- Standardize & reorganize the x86 percpu layout and
related cleanups (Brian Gerst)
- Convert the stackprotector canary to a regular percpu
variable (Brian Gerst)
- Add a percpu subsection for cache hot data (Brian Gerst)
- Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak)
- Construct __percpu_seg_override from __percpu_seg (Uros Bizjak)
MM:
- Add support for broadcast TLB invalidation using AMD's INVLPGB instruction
(Rik van Riel)
- Rework ROX cache to avoid writable copy (Mike Rapoport)
- PAT: restore large ROX pages after fragmentation
(Kirill A. Shutemov, Mike Rapoport)
- Make memremap(MEMREMAP_WB) map memory as encrypted by default
(Kirill A. Shutemov)
- Robustify page table initialization (Kirill A. Shutemov)
- Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn)
- Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW
(Matthew Wilcox)
KASLR:
- x86/kaslr: Reduce KASLR entropy on most x86 systems,
to support PCI BAR space beyond the 10TiB region
(CONFIG_PCI_P2PDMA=y) (Balbir Singh)
CPU bugs:
- Implement FineIBT-BHI mitigation (Peter Zijlstra)
- speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta)
- speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan Gupta)
- RFDS: Exclude P-only parts from the RFDS affected list (Pawan Gupta)
System calls:
- Break up entry/common.c (Brian Gerst)
- Move sysctls into arch/x86 (Joel Granados)
Intel LAM support updates: (Maciej Wieczor-Retman)
- selftests/lam: Move cpu_has_la57() to use cpuinfo flag
- selftests/lam: Skip test if LAM is disabled
- selftests/lam: Test get_user() LAM pointer handling
AMD SMN access updates:
- Add SMN offsets to exclusive region access (Mario Limonciello)
- Add support for debugfs access to SMN registers (Mario Limonciello)
- Have HSMP use SMN through AMD_NODE (Yazen Ghannam)
Power management updates: (Patryk Wlazlyn)
- Allow calling mwait_play_dead with an arbitrary hint
- ACPI/processor_idle: Add FFH state handling
- intel_idle: Provide the default enter_dead() handler
- Eliminate mwait_play_dead_cpuid_hint()
Bootup:
Build system:
- Raise the minimum GCC version to 8.1 (Brian Gerst)
- Raise the minimum LLVM version to 15.0.0
(Nathan Chancellor)
Kconfig: (Arnd Bergmann)
- Add cmpxchg8b support back to Geode CPUs
- Drop 32-bit "bigsmp" machine support
- Rework CONFIG_GENERIC_CPU compiler flags
- Drop configuration options for early 64-bit CPUs
- Remove CONFIG_HIGHMEM64G support
- Drop CONFIG_SWIOTLB for PAE
- Drop support for CONFIG_HIGHPTE
- Document CONFIG_X86_INTEL_MID as 64-bit-only
- Remove old STA2x11 support
- Only allow CONFIG_EISA for 32-bit
Headers:
- Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI headers
(Thomas Huth)
Assembly code & machine code patching:
- x86/alternatives: Simplify alternative_call() interface (Josh Poimboeuf)
- x86/alternatives: Simplify callthunk patching (Peter Zijlstra)
- KVM: VMX: Use named operands in inline asm (Josh Poimboeuf)
- x86/hyperv: Use named operands in inline asm (Josh Poimboeuf)
- x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra)
- x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h>
(Uros Bizjak)
- Use named operands in inline asm (Uros Bizjak)
- Improve performance by using asm_inline() for atomic locking instructions
(Uros Bizjak)
Earlyprintk:
- Harden early_serial (Peter Zijlstra)
NMI handler:
- Add an emergency handler in nmi_desc & use it in nmi_shootdown_cpus()
(Waiman Long)
Miscellaneous fixes and cleanups:
- by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel,
Artem Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst,
Dan Carpenter, Dr. David Alan Gilbert, H. Peter Anvin,
Ingo Molnar, Josh Poimboeuf, Kevin Brodsky, Mike Rapoport,
Lukas Bulwahn, Maciej Wieczor-Retman, Max Grobecker,
Patryk Wlazlyn, Pawan Gupta, Peter Zijlstra,
Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner,
Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak,
Vitaly Kuznetsov, Xin Li, liuye.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Dcb3
-----END PGP SIGNATURE-----
Merge tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core x86 updates from Ingo Molnar:
"x86 CPU features support:
- Generate the <asm/cpufeaturemasks.h> header based on build config
(H. Peter Anvin, Xin Li)
- x86 CPUID parsing updates and fixes (Ahmed S. Darwish)
- Introduce the 'setcpuid=' boot parameter (Brendan Jackman)
- Enable modifying CPU bug flags with '{clear,set}puid=' (Brendan
Jackman)
- Utilize CPU-type for CPU matching (Pawan Gupta)
- Warn about unmet CPU feature dependencies (Sohil Mehta)
- Prepare for new Intel Family numbers (Sohil Mehta)
Percpu code:
- Standardize & reorganize the x86 percpu layout and related cleanups
(Brian Gerst)
- Convert the stackprotector canary to a regular percpu variable
(Brian Gerst)
- Add a percpu subsection for cache hot data (Brian Gerst)
- Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak)
- Construct __percpu_seg_override from __percpu_seg (Uros Bizjak)
MM:
- Add support for broadcast TLB invalidation using AMD's INVLPGB
instruction (Rik van Riel)
- Rework ROX cache to avoid writable copy (Mike Rapoport)
- PAT: restore large ROX pages after fragmentation (Kirill A.
Shutemov, Mike Rapoport)
- Make memremap(MEMREMAP_WB) map memory as encrypted by default
(Kirill A. Shutemov)
- Robustify page table initialization (Kirill A. Shutemov)
- Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn)
- Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW
(Matthew Wilcox)
KASLR:
- x86/kaslr: Reduce KASLR entropy on most x86 systems, to support PCI
BAR space beyond the 10TiB region (CONFIG_PCI_P2PDMA=y) (Balbir
Singh)
CPU bugs:
- Implement FineIBT-BHI mitigation (Peter Zijlstra)
- speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta)
- speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan
Gupta)
- RFDS: Exclude P-only parts from the RFDS affected list (Pawan
Gupta)
System calls:
- Break up entry/common.c (Brian Gerst)
- Move sysctls into arch/x86 (Joel Granados)
Intel LAM support updates: (Maciej Wieczor-Retman)
- selftests/lam: Move cpu_has_la57() to use cpuinfo flag
- selftests/lam: Skip test if LAM is disabled
- selftests/lam: Test get_user() LAM pointer handling
AMD SMN access updates:
- Add SMN offsets to exclusive region access (Mario Limonciello)
- Add support for debugfs access to SMN registers (Mario Limonciello)
- Have HSMP use SMN through AMD_NODE (Yazen Ghannam)
Power management updates: (Patryk Wlazlyn)
- Allow calling mwait_play_dead with an arbitrary hint
- ACPI/processor_idle: Add FFH state handling
- intel_idle: Provide the default enter_dead() handler
- Eliminate mwait_play_dead_cpuid_hint()
Build system:
- Raise the minimum GCC version to 8.1 (Brian Gerst)
- Raise the minimum LLVM version to 15.0.0 (Nathan Chancellor)
Kconfig: (Arnd Bergmann)
- Add cmpxchg8b support back to Geode CPUs
- Drop 32-bit "bigsmp" machine support
- Rework CONFIG_GENERIC_CPU compiler flags
- Drop configuration options for early 64-bit CPUs
- Remove CONFIG_HIGHMEM64G support
- Drop CONFIG_SWIOTLB for PAE
- Drop support for CONFIG_HIGHPTE
- Document CONFIG_X86_INTEL_MID as 64-bit-only
- Remove old STA2x11 support
- Only allow CONFIG_EISA for 32-bit
Headers:
- Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI
headers (Thomas Huth)
Assembly code & machine code patching:
- x86/alternatives: Simplify alternative_call() interface (Josh
Poimboeuf)
- x86/alternatives: Simplify callthunk patching (Peter Zijlstra)
- KVM: VMX: Use named operands in inline asm (Josh Poimboeuf)
- x86/hyperv: Use named operands in inline asm (Josh Poimboeuf)
- x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra)
- x86/kexec: Merge x86_32 and x86_64 code using macros from
<asm/asm.h> (Uros Bizjak)
- Use named operands in inline asm (Uros Bizjak)
- Improve performance by using asm_inline() for atomic locking
instructions (Uros Bizjak)
Earlyprintk:
- Harden early_serial (Peter Zijlstra)
NMI handler:
- Add an emergency handler in nmi_desc & use it in
nmi_shootdown_cpus() (Waiman Long)
Miscellaneous fixes and cleanups:
- by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel, Artem
Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst, Dan
Carpenter, Dr. David Alan Gilbert, H. Peter Anvin, Ingo Molnar,
Josh Poimboeuf, Kevin Brodsky, Mike Rapoport, Lukas Bulwahn, Maciej
Wieczor-Retman, Max Grobecker, Patryk Wlazlyn, Pawan Gupta, Peter
Zijlstra, Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner,
Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak, Vitaly
Kuznetsov, Xin Li, liuye"
* tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (211 commits)
zstd: Increase DYNAMIC_BMI2 GCC version cutoff from 4.8 to 11.0 to work around compiler segfault
x86/asm: Make asm export of __ref_stack_chk_guard unconditional
x86/mm: Only do broadcast flush from reclaim if pages were unmapped
perf/x86/intel, x86/cpu: Replace Pentium 4 model checks with VFM ones
perf/x86/intel, x86/cpu: Simplify Intel PMU initialization
x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-UAPI headers
x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI headers
x86/locking/atomic: Improve performance by using asm_inline() for atomic locking instructions
x86/asm: Use asm_inline() instead of asm() in clwb()
x86/asm: Use CLFLUSHOPT and CLWB mnemonics in <asm/special_insns.h>
x86/hweight: Use asm_inline() instead of asm()
x86/hweight: Use ASM_CALL_CONSTRAINT in inline asm()
x86/hweight: Use named operands in inline asm()
x86/stackprotector/64: Only export __ref_stack_chk_guard on CONFIG_SMP
x86/head/64: Avoid Clang < 17 stack protector in startup code
x86/kexec: Merge x86_32 and x86_64 code using macros from <asm/asm.h>
x86/runtime-const: Add the RUNTIME_CONST_PTR assembly macro
x86/cpu/intel: Limit the non-architectural constant_tsc model checks
x86/mm/pat: Replace Intel x86_model checks with VFM ones
x86/cpu/intel: Fix fast string initialization for extended Families
...
-fmacro-prefix-map only affects __FILE__ and __BASE_FILE__.
Other references, for example in debug information, are not affected.
This makes handling of file references in the compiler outputs harder to
use and creates problems for reproducible builds.
Switch to -ffile-prefix map which affects all references.
Also drop the documentation section advising manual specification of
-fdebug-prefix-map for reproducible builds, as it is not necessary
anymore.
Suggested-by: Ben Hutchings <ben@decadent.org.uk>
Link: https://lore.kernel.org/lkml/c49cc967294f9a3a4a34f69b6a8727a6d3959ed8.camel@decadent.org.uk/
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Meanwhile explicitly state that the headers are uapi headers.
Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Xin Li (Intel) <xin@zytor.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
The imperative paradigm used to build vmlinux, extract some info from it
or perform some checks on it, and subsequently modify it again goes
against the declarative paradigm that is usually employed for defining
make rules.
In particular, the Makefile.postlink files that consume their input via
an output rule result in some dodgy logic in the decompressor makefiles
for RISC-V and x86, given that the vmlinux.relocs input file needed to
generate the arch-specific relocation tables may not exist or be out of
date, but cannot be constructed using the ordinary Make dependency based
rules, because the info needs to be extracted while vmlinux is in its
ephemeral, non-stripped form.
So instead, for architectures that require the static relocations that
are emitted into vmlinux when passing --emit-relocs to the linker, and
are subsequently stripped out again, introduce an intermediate vmlinux
target called vmlinux.unstripped, and organize the reset of the build
logic accordingly:
- vmlinux.unstripped is created only once, and not updated again
- build rules under arch/*/boot can depend on vmlinux.unstripped without
running the risk of the data disappearing or being out of date
- the final vmlinux generated by the build is not bloated with static
relocations that are never needed again after the build completes.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Some architectures build vmlinux with static relocations preserved, but
strip them again from the final vmlinux image. Arch specific tools
consume these static relocations in order to construct relocation tables
for KASLR.
The fact that vmlinux is created, consumed and subsequently updated goes
against the typical, declarative paradigm used by Make, which is based
on rules and dependencies. So as a first step towards cleaning this up,
introduce a Kconfig symbol to declare that the arch wants to consume the
static relocations emitted into vmlinux. This will be wired up further
in subsequent patches.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Remap source path prefixes in all output, including compiler
diagnostics, debug information, macro expansions, etc.
This removes a few absolute paths from the binary and also makes it
possible to use core::panic::Location properly.
Equivalent to the same configuration done for C sources in
commit 1d3730f001 ("kbuild: support -fmacro-prefix-map for external
modules") and commit a73619a845 ("kbuild: use -fmacro-prefix-map to
make __FILE__ a relative path").
Link: https://doc.rust-lang.org/rustc/command-line-arguments.html#--remap-path-prefix-remap-source-names-in-output
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Tested-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
userprogs sometimes need access to UAPI headers.
This is currently not possible for Usermode Linux, as UM is only
a pseudo architecture built on top of a regular architecture and does
not have its own UAPI.
Instead use the UAPI headers from the underlying regular architecture.
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Commit e27128db62 ("kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to
KBUILD_EXTRA_WARN") renamed KBUILD_ENABLE_EXTRA_GCC_CHECKS in 2019.
The migration in downstream code should be complete.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
The -fzero-init-padding-bits=all option is not a warning flag, so
defining it in scripts/Makefile.extrawarn is inconsistent.
Move it to the top-level Makefile for consistency.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
The userprog infrastructure links objects files through $(CC).
Either explicitly by manually calling $(CC) on multiple object files or
implicitly by directly compiling a source file to an executable.
The documentation at Documentation/kbuild/llvm.rst indicates that ld.lld
would be used for linking if LLVM=1 is specified.
However clang instead will use either a globally installed cross linker
from $PATH called ${target}-ld or fall back to the system linker, which
probably does not support crosslinking.
For the normal kernel build this is not an issue because the linker is
always executed directly, without the compiler being involved.
Explicitly pass --ld-path to clang so $(LD) is respected.
As clang 13.0.1 is required to build the kernel, this option is available.
Fixes: 7f3a59db27 ("kbuild: add infrastructure to build userspace programs")
Cc: stable@vger.kernel.org # needs wrapping in $(cc-option) for < 6.9
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
While WAIT_FOR_ENDBR is specified to be a full speculation stop; it
has been shown that some implementations are 'leaky' to such an extend
that speculation can escape even the FineIBT preamble.
To deal with this, add additional hardening to the FineIBT preamble.
Notably, using a new LLVM feature:
e223485c9b
which encodes the number of arguments in the kCFI preamble's register.
Using this register<->arity mapping, have the FineIBT preamble CALL
into a stub clobbering the relevant argument registers in the
speculative case.
Scott sayeth thusly:
Microarchitectural attacks such as Branch History Injection (BHI) and
Intra-mode Branch Target Injection (IMBTI) [1] can cause an indirect
call to mispredict to an adversary-influenced target within the same
hardware domain (e.g., within the kernel). Instructions at the
mispredicted target may execute speculatively and potentially expose
kernel data (e.g., to a user-mode adversary) through a
microarchitectural covert channel such as CPU cache state.
CET-IBT [2] is a coarse-grained control-flow integrity (CFI) ISA
extension that enforces that each indirect call (or indirect jump)
must land on an ENDBR (end branch) instruction, even speculatively*.
FineIBT is a software technique that refines CET-IBT by associating
each function type with a 32-bit hash and enforcing (at the callee)
that the hash of the caller's function pointer type matches the hash
of the callee's function type. However, recent research [3] has
demonstrated that the conditional branch that enforces FineIBT's hash
check can be coerced to mispredict, potentially allowing an adversary
to speculatively bypass the hash check:
__cfi_foo:
ENDBR64
SUB R10d, 0x01234567
JZ foo # Even if the hash check fails and ZF=0, this branch could still mispredict as taken
UD2
foo:
...
The techniques demonstrated in [3] require the attacker to be able to
control the contents of at least one live register at the mispredicted
target. Therefore, this patch set introduces a sequence of CMOV
instructions at each indirect-callable target that poisons every live
register with data that the attacker cannot control whenever the
FineIBT hash check fails, thus mitigating any potential attack.
The security provided by this scheme has been discussed in detail on
an earlier thread [4].
[1] https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/branch-history-injection.html
[2] Intel Software Developer's Manual, Volume 1, Chapter 18
[3] https://www.vusec.net/projects/native-bhi/
[4] https://lore.kernel.org/lkml/20240927194925.707462984@infradead.org/
*There are some caveats for certain processors, see [1] for more info
Suggested-by: Scott Constable <scott.d.constable@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/20250224124200.820402212@infradead.org
scripts/Makefile.clang was changed in the linked commit to move --target from
KBUILD_CFLAGS to KBUILD_CPPFLAGS, as that generally has a broader scope.
However that variable is not inspected by the userprogs logic,
breaking cross compilation on clang.
Use both variables to detect bitsize and target arguments for userprogs.
Fixes: feb843a469 ("kbuild: add $(CLANG_FLAGS) to KBUILD_CPPFLAGS")
Cc: stable@vger.kernel.org
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
When CONFIG_OBJTOOL=y or CONFIG_DEBUG_INFO_BTF=y, parallel builds
show awkward "mkdir -p ..." logs.
$ make -j16
[ snip ]
mkdir -p /home/masahiro/ref/linux/tools/objtool && make O=/home/masahiro/ref/linux subdir=tools/objtool --no-print-directory -C objtool
mkdir -p /home/masahiro/ref/linux/tools/bpf/resolve_btfids && make O=/home/masahiro/ref/linux subdir=tools/bpf/resolve_btfids --no-print-directory -C bpf/resolve_btfids
Defining MAKEFLAGS=<value> on the command line wipes out command line
switches from the resultant MAKEFLAGS definition, even though the command
line switches are active. [1]
MAKEFLAGS puts all single-letter options into the first word, and that
word will be empty if no single-letter options were given. [2]
However, this breaks if MAKEFLAGS=<value> is given on the command line.
The tools/ and tools/% targets set MAKEFLAGS=<value> on the command
line, which breaks the following code in tools/scripts/Makefile.include:
short-opts := $(firstword -$(MAKEFLAGS))
If MAKEFLAGS really needs modification, it should be done through the
environment variable, as follows:
MAKEFLAGS=<value> $(MAKE) ...
That said, I question whether modifying MAKEFLAGS is necessary here.
The only flag we might want to exclude is --no-print-directory, as the
tools build system changes the working directory. However, people might
find the "Entering/Leaving directory" logs annoying.
I simply removed the offending MAKEFLAGS=<value>.
[1]: https://savannah.gnu.org/bugs/?62469
[2]: https://www.gnu.org/software/make/manual/make.html#Testing-Flags
Fixes: ea01fa9f63 ("tools: Connect to the kernel build system")
Fixes: a50e433327 ("perf tools: Honor parallel jobs")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Daniel Xu <dxu@dxuuu.xyz>
Core
----
- More core refactoring to reduce the RTNL lock contention,
including preparatory work for the per-network namespace RTNL lock,
replacing RTNL lock with a per device-one to protect NAPI-related
net device data and moving synchronize_net() calls outside such
lock.
- Extend drop reasons usage, adding net scheduler, AF_UNIX, bridge and
more specific TCP coverage.
- Reduce network namespace tear-down time by removing per-subsystems
synchronize_net() in tipc and sched.
- Add flow label selector support for fib rules, allowing traffic
redirection based on such header field.
Netfilter
---------
- Do not remove netdev basechain when last device is gone, allowing
netdev basechains without devices.
- Revisit the flowtable teardown strategy, dealing better with fin,
reset and re-open events.
- Scale-up IP-vs connection dumping by avoiding linear search on
each restart.
Protocols
---------
- A significant XDP socket refactor, consolidating and optimizing
several helpers into the core
- Better scaling of ICMP rate-limiting, by removing false-sharing in
inet peers handling.
- Introduces netlink notifications for multicast IPv4 and IPv6
address changes.
- Add ipsec support for IP-TFS/AggFrag encapsulation, allowing
aggregation and fragmentation of the inner IP.
- Add sysctl to configure TIME-WAIT reuse delay for TCP sockets,
to avoid local port exhaustion issues when the average connection
lifetime is very short.
- Support updating keys (re-keying) for connections using kernel
TLS (for TLS 1.3 only).
- Support ipv4-mapped ipv6 address clients in smc-r v2.
- Add support for jumbo data packet transmission in RxRPC sockets,
gluing multiple data packets in a single UDP packet.
- Support RxRPC RACK-TLP to manage packet loss and retransmission in
conjunction with the congestion control algorithm.
Driver API
----------
- Introduce a unified and structured interface for reporting PHY
statistics, exposing consistent data across different H/W via
ethtool.
- Make timestamping selectable, allow the user to select the desired
hwtstamp provider (PHY or MAC) administratively.
- Add support for configuring a header-data-split threshold (HDS)
value via ethtool, to deal with partial or buggy H/W implementation.
- Consolidate DSA drivers Energy Efficiency Ethernet support.
- Add EEE management to phylink, making use of the phylib
implementation.
- Add phylib support for in-band capabilities negotiation.
- Simplify how phylib-enabled mac drivers expose the supported
interfaces.
Tests and tooling
-----------------
- Make the YNL tool package-friendly to make it easier to deploy it
separately from the kernel.
- Increase TCP selftest coverage importing several packetdrill
test-cases.
- Regenerate the ethtool uapi header from the YNL spec,
to ease maintenance and future development.
- Add YNL support for decoding the link types used in net
self-tests, allowing a single build to run both net and
drivers/net.
Drivers
-------
- Ethernet high-speed NICs:
- nVidia/Mellanox (mlx5):
- add cross E-Switch QoS support
- add SW Steering support for ConnectX-8
- implement support for HW-Managed Flow Steering, improving the
rule deletion/insertion rate
- support for multi-host LAG
- Intel (ixgbe, ice, igb):
- ice: add support for devlink health events
- ixgbe: add initial support for E610 chipset variant
- igb: add support for AF_XDP zero-copy
- Meta:
- add support for basic RSS config
- allow changing the number of channels
- add hardware monitoring support
- Broadcom (bnxt):
- implement TCP data split and HDS threshold ethtool support,
enabling Device Memory TCP.
- Marvell Octeon:
- implement egress ipsec offload support for the cn10k family
- Hisilicon (HIBMC):
- implement unicast MAC filtering
- Ethernet NICs embedded and virtual:
- Convert UDP tunnel drivers to NETDEV_PCPU_STAT_DSTATS, avoiding
contented atomic operations for drop counters
- Freescale:
- quicc: phylink conversion
- enetc: support Tx and Rx checksum offload and improve TSO
performances
- MediaTek:
- airoha: introduce support for ETS and HTB Qdisc offload
- Microchip:
- lan78XX USB: preparation work for phylink conversion
- Synopsys (stmmac):
- support DWMAC IP on NXP Automotive SoCs S32G2xx/S32G3xx/S32R45
- refactor EEE support to leverage the new driver API
- optimize DMA and cache access to increase raw RX performances
by 40%
- TI:
- icssg-prueth: add multicast filtering support for VLAN
interface
- netkit:
- add ability to configure head/tailroom
- VXLAN:
- accepts packets with user-defined reserved bit
- Ethernet switches:
- Microchip:
- lan969x: add RGMII support
- lan969x: improve TX and RX performance using the FDMA engine
- nVidia/Mellanox:
- move Tx header handling to PCI driver, to ease XDP support
- Ethernet PHYs:
- Texas Instruments DP83822:
- add support for GPIO2 clock output
- Realtek:
- 8169: add support for RTL8125D rev.b
- rtl822x: add hwmon support for the temperature sensor
- Microchip:
- add support for RDS PTP hardware
- consolidate periodic output signal generation
- CAN:
- several DT-bindings to DT schema conversions
- tcan4x5x:
- add HW standby support
- support nWKRQ voltage selection
- kvaser:
- allowing Bus Error Reporting runtime configuration
- WiFi:
- the on-going Multi-Link Operation (MLO) effort continues, affecting
both the stack and in drivers
- mac80211/cfg80211:
- Emergency Preparedness Communication Services (EPCS) station mode
support
- support for adding and removing station links for MLO
- add support for WiFi 7/EHT mesh over 320 MHz channels
- report Tx power info for each link
- RealTek (rtw88):
- enable USB Rx aggregation and USB 3 to improve performance
- LED support
- RealTek (rtw89):
- refactor power save to support Multi-Link Operations
- add support for RTL8922AE-VS variant
- MediaTek (mt76):
- single wiphy multiband support (preparation for MLO)
- p2p device support
- add TP-Link TXE50UH USB adapter support
- Qualcomm (ath10k):
- support for the QCA6698AQ IP core
- Qualcomm (ath12k):
- enable MLO for QCN9274
- Bluetooth:
- Allow sysfs to trigger hdev reset, to allow recovering devices
not responsive from user-space
- MediaTek: add support for MT7922, MT7925, MT7921e devices
- Realtek: add support for RTL8851BE devices
- Qualcomm: add support for WCN785x devices
- ISO: allow BIG re-sync
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-----BEGIN PGP SIGNATURE-----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=hrsp
-----END PGP SIGNATURE-----
Merge tag 'net-next-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Paolo Abeni:
"This is slightly smaller than usual, with the most interesting work
being still around RTNL scope reduction.
Core:
- More core refactoring to reduce the RTNL lock contention, including
preparatory work for the per-network namespace RTNL lock, replacing
RTNL lock with a per device-one to protect NAPI-related net device
data and moving synchronize_net() calls outside such lock.
- Extend drop reasons usage, adding net scheduler, AF_UNIX, bridge
and more specific TCP coverage.
- Reduce network namespace tear-down time by removing per-subsystems
synchronize_net() in tipc and sched.
- Add flow label selector support for fib rules, allowing traffic
redirection based on such header field.
Netfilter:
- Do not remove netdev basechain when last device is gone, allowing
netdev basechains without devices.
- Revisit the flowtable teardown strategy, dealing better with fin,
reset and re-open events.
- Scale-up IP-vs connection dumping by avoiding linear search on each
restart.
Protocols:
- A significant XDP socket refactor, consolidating and optimizing
several helpers into the core
- Better scaling of ICMP rate-limiting, by removing false-sharing in
inet peers handling.
- Introduces netlink notifications for multicast IPv4 and IPv6
address changes.
- Add ipsec support for IP-TFS/AggFrag encapsulation, allowing
aggregation and fragmentation of the inner IP.
- Add sysctl to configure TIME-WAIT reuse delay for TCP sockets, to
avoid local port exhaustion issues when the average connection
lifetime is very short.
- Support updating keys (re-keying) for connections using kernel TLS
(for TLS 1.3 only).
- Support ipv4-mapped ipv6 address clients in smc-r v2.
- Add support for jumbo data packet transmission in RxRPC sockets,
gluing multiple data packets in a single UDP packet.
- Support RxRPC RACK-TLP to manage packet loss and retransmission in
conjunction with the congestion control algorithm.
Driver API:
- Introduce a unified and structured interface for reporting PHY
statistics, exposing consistent data across different H/W via
ethtool.
- Make timestamping selectable, allow the user to select the desired
hwtstamp provider (PHY or MAC) administratively.
- Add support for configuring a header-data-split threshold (HDS)
value via ethtool, to deal with partial or buggy H/W
implementation.
- Consolidate DSA drivers Energy Efficiency Ethernet support.
- Add EEE management to phylink, making use of the phylib
implementation.
- Add phylib support for in-band capabilities negotiation.
- Simplify how phylib-enabled mac drivers expose the supported
interfaces.
Tests and tooling:
- Make the YNL tool package-friendly to make it easier to deploy it
separately from the kernel.
- Increase TCP selftest coverage importing several packetdrill
test-cases.
- Regenerate the ethtool uapi header from the YNL spec, to ease
maintenance and future development.
- Add YNL support for decoding the link types used in net self-tests,
allowing a single build to run both net and drivers/net.
Drivers:
- Ethernet high-speed NICs:
- nVidia/Mellanox (mlx5):
- add cross E-Switch QoS support
- add SW Steering support for ConnectX-8
- implement support for HW-Managed Flow Steering, improving the
rule deletion/insertion rate
- support for multi-host LAG
- Intel (ixgbe, ice, igb):
- ice: add support for devlink health events
- ixgbe: add initial support for E610 chipset variant
- igb: add support for AF_XDP zero-copy
- Meta:
- add support for basic RSS config
- allow changing the number of channels
- add hardware monitoring support
- Broadcom (bnxt):
- implement TCP data split and HDS threshold ethtool support,
enabling Device Memory TCP.
- Marvell Octeon:
- implement egress ipsec offload support for the cn10k family
- Hisilicon (HIBMC):
- implement unicast MAC filtering
- Ethernet NICs embedded and virtual:
- Convert UDP tunnel drivers to NETDEV_PCPU_STAT_DSTATS, avoiding
contented atomic operations for drop counters
- Freescale:
- quicc: phylink conversion
- enetc: support Tx and Rx checksum offload and improve TSO
performances
- MediaTek:
- airoha: introduce support for ETS and HTB Qdisc offload
- Microchip:
- lan78XX USB: preparation work for phylink conversion
- Synopsys (stmmac):
- support DWMAC IP on NXP Automotive SoCs S32G2xx/S32G3xx/S32R45
- refactor EEE support to leverage the new driver API
- optimize DMA and cache access to increase raw RX performances
by 40%
- TI:
- icssg-prueth: add multicast filtering support for VLAN
interface
- netkit:
- add ability to configure head/tailroom
- VXLAN:
- accepts packets with user-defined reserved bit
- Ethernet switches:
- Microchip:
- lan969x: add RGMII support
- lan969x: improve TX and RX performance using the FDMA engine
- nVidia/Mellanox:
- move Tx header handling to PCI driver, to ease XDP support
- Ethernet PHYs:
- Texas Instruments DP83822:
- add support for GPIO2 clock output
- Realtek:
- 8169: add support for RTL8125D rev.b
- rtl822x: add hwmon support for the temperature sensor
- Microchip:
- add support for RDS PTP hardware
- consolidate periodic output signal generation
- CAN:
- several DT-bindings to DT schema conversions
- tcan4x5x:
- add HW standby support
- support nWKRQ voltage selection
- kvaser:
- allowing Bus Error Reporting runtime configuration
- WiFi:
- the on-going Multi-Link Operation (MLO) effort continues,
affecting both the stack and in drivers
- mac80211/cfg80211:
- Emergency Preparedness Communication Services (EPCS) station
mode support
- support for adding and removing station links for MLO
- add support for WiFi 7/EHT mesh over 320 MHz channels
- report Tx power info for each link
- RealTek (rtw88):
- enable USB Rx aggregation and USB 3 to improve performance
- LED support
- RealTek (rtw89):
- refactor power save to support Multi-Link Operations
- add support for RTL8922AE-VS variant
- MediaTek (mt76):
- single wiphy multiband support (preparation for MLO)
- p2p device support
- add TP-Link TXE50UH USB adapter support
- Qualcomm (ath10k):
- support for the QCA6698AQ IP core
- Qualcomm (ath12k):
- enable MLO for QCN9274
- Bluetooth:
- Allow sysfs to trigger hdev reset, to allow recovering devices
not responsive from user-space
- MediaTek: add support for MT7922, MT7925, MT7921e devices
- Realtek: add support for RTL8851BE devices
- Qualcomm: add support for WCN785x devices
- ISO: allow BIG re-sync"
* tag 'net-next-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1386 commits)
net/rose: prevent integer overflows in rose_setsockopt()
net: phylink: fix regression when binding a PHY
net: ethernet: ti: am65-cpsw: streamline TX queue creation and cleanup
net: ethernet: ti: am65-cpsw: streamline RX queue creation and cleanup
net: ethernet: ti: am65-cpsw: ensure proper channel cleanup in error path
ipv6: Convert inet6_rtm_deladdr() to per-netns RTNL.
ipv6: Convert inet6_rtm_newaddr() to per-netns RTNL.
ipv6: Move lifetime validation to inet6_rtm_newaddr().
ipv6: Set cfg.ifa_flags before device lookup in inet6_rtm_newaddr().
ipv6: Pass dev to inet6_addr_add().
ipv6: Convert inet6_ioctl() to per-netns RTNL.
ipv6: Hold rtnl_net_lock() in addrconf_init() and addrconf_cleanup().
ipv6: Hold rtnl_net_lock() in addrconf_dad_work().
ipv6: Hold rtnl_net_lock() in addrconf_verify_work().
ipv6: Convert net.ipv6.conf.${DEV}.XXX sysctl to per-netns RTNL.
ipv6: Add __in6_dev_get_rtnl_net().
net: stmmac: Drop redundant skb_mark_for_recycle() for SKB frags
net: mii: Fix the Speed display when the network cable is not connected
sysctl net: Remove macro checks for CONFIG_SYSCTL
eth: bnxt: update header sizing defaults
...
Toolchain and infrastructure:
- Finish the move to custom FFI integer types started in the previous
cycle and finally map 'long' to 'isize' and 'char' to 'u8'. Do a few
cleanups on top thanks to that.
- Start to use 'derive(CoercePointee)' on Rust >= 1.84.0.
This is a major milestone on the path to build the kernel using only
stable Rust features. In particular, previously we were using the
unstable features 'coerce_unsized', 'dispatch_from_dyn' and 'unsize',
and now we will use the new 'derive_coerce_pointee' one, which is on
track to stabilization. This new feature is a macro that essentially
expands into code that internally uses the unstable features that we
were using before, without having to expose those.
With it, stable Rust users, including the kernel, will be able to
build custom smart pointers that work with trait objects, e.g.:
fn f(p: &Arc<dyn Display>) {
pr_info!("{p}\n");
}
let a: Arc<dyn Display> = Arc::new(42i32, GFP_KERNEL)?;
let b: Arc<dyn Display> = Arc::new("hello there", GFP_KERNEL)?;
f(&a); // Prints "42".
f(&b); // Prints "hello there".
Together with the 'arbitrary_self_types' feature that we started
using in the previous cycle, using our custom smart pointers like
'Arc' will eventually only rely in stable Rust.
- Introduce 'PROCMACROLDFLAGS' environment variable to allow to link
Rust proc macros using different flags than those used for linking
Rust host programs (e.g. when 'rustc' uses a different C library
than the host programs' one), which Android needs.
- Help kernel builds under macOS with Rust enabled by accomodating
other naming conventions for dynamic libraries (i.e. '.so' vs.
'.dylib') which are used for Rust procedural macros. The actual
support for macOS (i.e. the rest of the pieces needed) is provided
out-of-tree by others, following the policy used for other parts of
the kernel by Kbuild.
- Run Clippy for 'rusttest' code too and clean the bits it spotted.
- Provide Clippy with the minimum supported Rust version to improve
the suggestions it gives.
- Document 'bindgen' 0.71.0 regression.
'kernel' crate:
- 'build_error!': move users of the hidden function to the documented
macro, prevent such uses in the future by moving the function
elsewhere and add the macro to the prelude.
- 'types' module: add improved version of 'ForeignOwnable::borrow_mut'
(which was removed in the past since it was problematic); change
'ForeignOwnable' pointer type to '*mut'.
- 'alloc' module: implement 'Display' for 'Box' and align the 'Debug'
implementation to it; add example (doctest) for 'ArrayLayout::new()'.
- 'sync' module: document 'PhantomData' in 'Arc'; use
'NonNull::new_unchecked' in 'ForeignOwnable for Arc' impl.
- 'uaccess' module: accept 'Vec's with different allocators in
'UserSliceReader::read_all'.
- 'workqueue' module: enable run-testing a couple more doctests.
- 'error' module: simplify 'from_errno()'.
- 'block' module: fix formatting in code documentation (a lint to catch
these is being implemented).
- Avoid 'unwrap()'s in doctests, which also improves the examples by
showing how kernel code is supposed to be written.
- Avoid 'as' casts with 'cast{,_mut}' calls which are a bit safer.
And a few other cleanups.
-----BEGIN PGP SIGNATURE-----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=VLNX
-----END PGP SIGNATURE-----
Merge tag 'rust-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Finish the move to custom FFI integer types started in the previous
cycle and finally map 'long' to 'isize' and 'char' to 'u8'. Do a
few cleanups on top thanks to that.
- Start to use 'derive(CoercePointee)' on Rust >= 1.84.0.
This is a major milestone on the path to build the kernel using
only stable Rust features. In particular, previously we were using
the unstable features 'coerce_unsized', 'dispatch_from_dyn' and
'unsize', and now we will use the new 'derive_coerce_pointee' one,
which is on track to stabilization. This new feature is a macro
that essentially expands into code that internally uses the
unstable features that we were using before, without having to
expose those.
With it, stable Rust users, including the kernel, will be able to
build custom smart pointers that work with trait objects, e.g.:
fn f(p: &Arc<dyn Display>) {
pr_info!("{p}\n");
}
let a: Arc<dyn Display> = Arc::new(42i32, GFP_KERNEL)?;
let b: Arc<dyn Display> = Arc::new("hello there", GFP_KERNEL)?;
f(&a); // Prints "42".
f(&b); // Prints "hello there".
Together with the 'arbitrary_self_types' feature that we started
using in the previous cycle, using our custom smart pointers like
'Arc' will eventually only rely in stable Rust.
- Introduce 'PROCMACROLDFLAGS' environment variable to allow to link
Rust proc macros using different flags than those used for linking
Rust host programs (e.g. when 'rustc' uses a different C library
than the host programs' one), which Android needs.
- Help kernel builds under macOS with Rust enabled by accomodating
other naming conventions for dynamic libraries (i.e. '.so' vs.
'.dylib') which are used for Rust procedural macros. The actual
support for macOS (i.e. the rest of the pieces needed) is provided
out-of-tree by others, following the policy used for other parts of
the kernel by Kbuild.
- Run Clippy for 'rusttest' code too and clean the bits it spotted.
- Provide Clippy with the minimum supported Rust version to improve
the suggestions it gives.
- Document 'bindgen' 0.71.0 regression.
'kernel' crate:
- 'build_error!': move users of the hidden function to the documented
macro, prevent such uses in the future by moving the function
elsewhere and add the macro to the prelude.
- 'types' module: add improved version of 'ForeignOwnable::borrow_mut'
(which was removed in the past since it was problematic); change
'ForeignOwnable' pointer type to '*mut'.
- 'alloc' module: implement 'Display' for 'Box' and align the 'Debug'
implementation to it; add example (doctest) for 'ArrayLayout::new()'
- 'sync' module: document 'PhantomData' in 'Arc'; use
'NonNull::new_unchecked' in 'ForeignOwnable for Arc' impl.
- 'uaccess' module: accept 'Vec's with different allocators in
'UserSliceReader::read_all'.
- 'workqueue' module: enable run-testing a couple more doctests.
- 'error' module: simplify 'from_errno()'.
- 'block' module: fix formatting in code documentation (a lint to catch
these is being implemented).
- Avoid 'unwrap()'s in doctests, which also improves the examples by
showing how kernel code is supposed to be written.
- Avoid 'as' casts with 'cast{,_mut}' calls which are a bit safer.
And a few other cleanups"
* tag 'rust-6.14' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (32 commits)
kbuild: rust: add PROCMACROLDFLAGS
rust: uaccess: generalize userSliceReader to support any Vec
rust: kernel: add improved version of `ForeignOwnable::borrow_mut`
rust: kernel: reorder `ForeignOwnable` items
rust: kernel: change `ForeignOwnable` pointer to mut
rust: arc: split unsafe block, add missing comment
rust: types: avoid `as` casts
rust: arc: use `NonNull::new_unchecked`
rust: use derive(CoercePointee) on rustc >= 1.84.0
rust: alloc: add doctest for `ArrayLayout::new()`
rust: init: update `stack_try_pin_init` examples
rust: error: import `kernel`'s `LayoutError` instead of `core`'s
rust: str: replace unwraps with question mark operators
rust: page: remove unnecessary helper function from doctest
rust: rbtree: remove unwrap in asserts
rust: init: replace unwraps with question mark operators
rust: use host dylib naming convention to support macOS
rust: add `build_error!` to the prelude
rust: kernel: move `build_error` hidden function to prevent mistakes
rust: use the `build_error!` macro, not the hidden function
...
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 <elsk@google.com>
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 <aliceryhl@google.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: HONG Yifan <elsk@google.com>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20241112184455.855133-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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 <da.gomez@samsung.com>
Co-developed-by: Fiona Behrens <me@kloenk.dev>
Signed-off-by: Fiona Behrens <me@kloenk.dev>
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
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 <ojeda@kernel.org>
This is new API which caters to the following requirements:
- Pack or unpack a large number of fields to/from a buffer with a small
code footprint. The current alternative is to open-code a large number
of calls to pack() and unpack(), or to use packing() to reduce that
number to half. But packing() is not const-correct.
- Use unpacked numbers stored in variables smaller than u64. This
reduces the rodata footprint of the stored field arrays.
- Perform error checking at compile time, rather than runtime, and return
void from the API functions. Because the C preprocessor can't generate
variable length code (loops), this is a bit tricky to do with macros.
To handle this, implement macros which sanity check the packed field
definitions based on their size. Finally, a single macro with a chain of
__builtin_choose_expr() is used to select the appropriate macros. We
enforce the use of ascending or descending order to avoid O(N^2) scaling
when checking for overlap. Note that the macros are written with care to
ensure that the compilers can correctly evaluate the resulting code at
compile time. In particular, care was taken with avoiding too many nested
statement expressions. Nested statement expressions trip up some
compilers, especially when passing down variables created in previous
statement expressions.
There are two key design choices intended to keep the overall macro code
size small. First, the definition of each CHECK_PACKED_FIELDS_N macro is
implemented recursively, by calling the N-1 macro. This avoids needing
the code to repeat multiple times.
Second, the CHECK_PACKED_FIELD macro enforces that the fields in the
array are sorted in order. This allows checking for overlap only with
neighboring fields, rather than the general overlap case where each field
would need to be checked against other fields.
The overlap checks use the first two fields to determine the order of the
remaining fields, thus allowing either ascending or descending order.
This enables drivers the flexibility to keep the fields ordered in which
ever order most naturally fits their hardware design and its associated
documentation.
The CHECK_PACKED_FIELDS macro is directly called from within pack_fields
and unpack_fields, ensuring that all drivers using the API receive the
benefits of the compile-time checks. Users do not need to directly call
any of the macros directly.
The CHECK_PACKED_FIELDS and its helper macros CHECK_PACKED_FIELDS_(0..50)
are generated using a simple C program in scripts/gen_packed_field_checks.c
This program can be compiled on demand and executed to generate the
macro code in include/linux/packing.h. This will aid in the event that a
driver needs more than 50 fields. The generator can be updated with a new
size, and used to update the packing.h header file. In practice, the ice
driver will need to support 27 fields, and the sja1105 driver will need
to support 0 fields. This on-demand generation avoids the need to modify
Kbuild. We do not anticipate the maximum number of fields to grow very
often.
- Reduced rodata footprint for the storage of the packed field arrays.
To that end, we have struct packed_field_u8 and packed_field_u16, which
define the fields with the associated type. More can be added as
needed (unlikely for now). On these types, the same generic pack_fields()
and unpack_fields() API can be used, thanks to the new C11 _Generic()
selection feature, which can call pack_fields_u8() or pack_fields_16(),
depending on the type of the "fields" array - a simplistic form of
polymorphism. It is evaluated at compile time which function will actually
be called.
Over time, packing() is expected to be completely replaced either with
pack() or with pack_fields().
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Co-developed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://patch.msgid.link/20241210-packing-pack-fields-and-ice-implementation-v10-3-ee56a47479ac@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
- 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
-----BEGIN PGP SIGNATURE-----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=GDKD
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
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()
...
Replace lz4c with lz4 for kernel image compression.
Although lz4 and lz4c are functionally similar, lz4c has been deprecated
upstream since 2018. Since as early as Ubuntu 16.04 and Fedora 25, lz4
and lz4c have been packaged together, making it safe to update the
requirement from lz4c to lz4.
Consequently, some distributions and build systems, such as OpenEmbedded,
have fully transitioned to using lz4. OpenEmbedded core adopted this
change in commit fe167e082cbd ("bitbake.conf: require lz4 instead of
lz4c"), causing compatibility issues when building the mainline kernel
in the latest OpenEmbedded environment, as seen in the errors below.
This change also updates the LZ4 compression commands to make it backward
compatible by replacing stdin and stdout with the '-' option, due to some
unclear reason, the stdout keyword does not work for lz4 and '-' works for
both. In addition, this modifies the legacy '-c1' with '-9' which is also
compatible with both. This fixes the mainline kernel build failures with
the latest master OpenEmbedded builds associated with the mentioned
compatibility issues.
LZ4 arch/arm/boot/compressed/piggy_data
/bin/sh: 1: lz4c: not found
...
...
ERROR: oe_runmake failed
Link: https://github.com/lz4/lz4/pull/553
Suggested-by: Francesco Dolcini <francesco.dolcini@toradex.com>
Signed-off-by: Parth Pancholi <parth.pancholi@toradex.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
This rule is unnecessary because you can generate foo/bar.symtypes
as a side effect using:
$ make KBUILD_SYMTYPES=1 foo/bar.o
While compiling *.o is slower than preprocessing, the impact is
negligible. I prioritize keeping the code simpler.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Unless an explicit O= option is provided, external module builds must
start from the kernel directory.
This can be achieved by using the -C option:
$ make -C /path/to/kernel M=/path/to/external/module
This commit allows starting external module builds from any directory,
so you can also do the following:
$ make -f /path/to/kernel/Makefile M=/path/to/external/module
The key difference is that the -C option changes the working directory
and parses the Makefile located there, while the -f option only
specifies the Makefile to use.
As shown in the examples in Documentation/kbuild/modules.rst, external
modules usually have a wrapper Makefile that allows you to build them
without specifying any make arguments. The Makefile typically contains
a rule as follows:
KDIR ?= /path/to/kernel
default:
$(MAKE) -C $(KDIR) M=$(CURDIR) $(MAKECMDGOALS)
The log will appear as follows:
$ make
make -C /path/to/kernel M=/path/to/external/module
make[1]: Entering directory '/path/to/kernel'
make[2]: Entering directory '/path/to/external/module'
CC [M] helloworld.o
MODPOST Module.symvers
CC [M] helloworld.mod.o
CC [M] .module-common.o
LD [M] helloworld.ko
make[2]: Leaving directory '/path/to/external/module'
make[1]: Leaving directory '/path/to/kernel'
This changes the working directory twice because the -C option first
switches to the kernel directory, and then Kbuild internally recurses
back to the external module directory.
With this commit, the wrapper Makefile can directly include the kernel
Makefile:
KDIR ?= /path/to/kernel
export KBUILD_EXTMOD := $(realpath $(dir $(lastword $(MAKEFILE_LIST))))
include $(KDIR)/Makefile
This avoids unnecessary sub-make invocations:
$ make
CC [M] helloworld.o
MODPOST Module.symvers
CC [M] helloworld.mod.o
CC [M] .module-common.o
LD [M] helloworld.ko
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
When Kbuild starts building in a separate output directory, it generates
a wrapper Makefile, allowing you to invoke 'make' from the output
directory.
This commit makes it more convenient, so you can invoke 'make' without
M= or MO=.
First, you need to build external modules in a separate directory:
$ make M=/path/to/module/source/dir MO=/path/to/module/build/dir
Once the wrapper Makefile is generated in /path/to/module/build/dir,
you can proceed as follows:
$ cd /path/to/module/build/dir
$ make
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Keep the consistent behavior when this Makefile is invoked from another
directory.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
This commit makes -fmacro-prefix-map work for external modules built in
a separate output directory. It improves the reproducibility of external
modules and provides the benefits described in commit a73619a845
("kbuild: use -fmacro-prefix-map to make __FILE__ a relative path").
When building_out_of_srctree is not defined (e.g., when the kernel or
external module is built in the source directory), this option is
unnecessary.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
There has been a long-standing request to support building external
modules in a separate build directory.
This commit introduces a new environment variable, KBUILD_EXTMOD_OUTPUT,
and its shorthand Make variable, MO.
A simple usage:
$ make -C <kernel-dir> M=<module-src-dir> MO=<module-build-dir>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
With the previous changes, $(extmod_prefix), $(MODORDER), and
$(MODULES_NSDEPS) are constant. (empty, modules.order, and
modules.nsdeps, respectively).
Remove these variables and hard-code their values.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Currently, Kbuild always operates in the output directory of the kernel,
even when building external modules. This increases the risk of external
module Makefiles attempting to write to the kernel directory.
This commit switches the working directory to the external module
directory, allowing the removal of the $(KBUILD_EXTMOD)/ prefix from
some build artifacts.
The command for building external modules maintains backward
compatibility, but Makefiles that rely on working in the kernel
directory may break. In such cases, $(objtree) and $(srctree) should
be used to refer to the output and source directories of the kernel.
The appearance of the build log will change as follows:
[Before]
$ make -C /path/to/my/linux M=/path/to/my/externel/module
make: Entering directory '/path/to/my/linux'
CC [M] /path/to/my/externel/module/helloworld.o
MODPOST /path/to/my/externel/module/Module.symvers
CC [M] /path/to/my/externel/module/helloworld.mod.o
CC [M] /path/to/my/externel/module/.module-common.o
LD [M] /path/to/my/externel/module/helloworld.ko
make: Leaving directory '/path/to/my/linux'
[After]
$ make -C /path/to/my/linux M=/path/to/my/externel/module
make: Entering directory '/path/to/my/linux'
make[1]: Entering directory '/path/to/my/externel/module'
CC [M] helloworld.o
MODPOST Module.symvers
CC [M] helloworld.mod.o
CC [M] .module-common.o
LD [M] helloworld.ko
make[1]: Leaving directory '/path/to/my/externel/module'
make: Leaving directory '/path/to/my/linux'
Printing "Entering directory" twice is cumbersome. This will be
addressed later.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Highlights for this merge window:
* The whole caching of module code into huge pages by Mike Rapoport is going
in through Andrew Morton's tree due to some other code dependencies. That's
really the biggest highlight for Linux kernel modules in this release. With
it we share huge pages for modules, starting off with x86. Expect to see that
soon through Andrew!
* Helge Deller addressed some lingering low hanging fruit alignment
enhancements by. It is worth pointing out that from his old patch series
I dropped his vmlinux.lds.h change at Masahiro's request as he would
prefer this to be specified in asm code [0].
[0] https://lore.kernel.org/all/20240129192644.3359978-5-mcgrof@kernel.org/T/#m9efef5e700fbecd28b7afb462c15eed8ba78ef5a
* Matthew Maurer and Sami Tolvanen have been tag teaming to help
get us closer to a modversions for Rust. In this cycle we take in
quite a lot of the refactoring for ELF validation. I expect modversions
for Rust will be merged by v6.14 as that code is mostly ready now.
* Adds a new modules selftests: kallsyms which helps us tests find_symbol()
and the limits of kallsyms on Linux today.
* We have a realtime mailing list to kernel-ci testing for modules now
which relies and combines patchwork, kpd and kdevops:
- https://patchwork.kernel.org/project/linux-modules/list/
- https://github.com/linux-kdevops/kdevops/blob/main/docs/kernel-ci/README.md
- https://github.com/linux-kdevops/kdevops/blob/main/docs/kernel-ci/kernel-ci-kpd.md
- https://github.com/linux-kdevops/kdevops/blob/main/docs/kernel-ci/linux-modules-kdevops-ci.md
If you want to help avoid Linux kernel modules regressions, now its simple,
just add a new Linux modules sefltests under tools/testing/selftests/module/
That is it. All new selftests will be used and leveraged automatically by
the CI.
-----BEGIN PGP SIGNATURE-----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=Ny84
-----END PGP SIGNATURE-----
Merge tag 'modules-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux
Pull modules updates from Luis Chamberlain:
- The whole caching of module code into huge pages by Mike Rapoport is
going in through Andrew Morton's tree due to some other code
dependencies. That's really the biggest highlight for Linux kernel
modules in this release. With it we share huge pages for modules,
starting off with x86. Expect to see that soon through Andrew!
- Helge Deller addressed some lingering low hanging fruit alignment
enhancements by. It is worth pointing out that from his old patch
series I dropped his vmlinux.lds.h change at Masahiro's request as he
would prefer this to be specified in asm code [0].
[0] https://lore.kernel.org/all/20240129192644.3359978-5-mcgrof@kernel.org/T/#m9efef5e700fbecd28b7afb462c15eed8ba78ef5a
- Matthew Maurer and Sami Tolvanen have been tag teaming to help get us
closer to a modversions for Rust. In this cycle we take in quite a
lot of the refactoring for ELF validation. I expect modversions for
Rust will be merged by v6.14 as that code is mostly ready now.
- Adds a new modules selftests: kallsyms which helps us tests
find_symbol() and the limits of kallsyms on Linux today.
- We have a realtime mailing list to kernel-ci testing for modules now
which relies and combines patchwork, kpd and kdevops:
https://patchwork.kernel.org/project/linux-modules/list/https://github.com/linux-kdevops/kdevops/blob/main/docs/kernel-ci/README.mdhttps://github.com/linux-kdevops/kdevops/blob/main/docs/kernel-ci/kernel-ci-kpd.mdhttps://github.com/linux-kdevops/kdevops/blob/main/docs/kernel-ci/linux-modules-kdevops-ci.md
If you want to help avoid Linux kernel modules regressions, now its
simple, just add a new Linux modules sefltests under
tools/testing/selftests/module/ That is it. All new selftests will be
used and leveraged automatically by the CI.
* tag 'modules-6.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/modules/linux:
tests/module/gen_test_kallsyms.sh: use 0 value for variables
scripts: Remove export_report.pl
selftests: kallsyms: add MODULE_DESCRIPTION
selftests: add new kallsyms selftests
module: Reformat struct for code style
module: Additional validation in elf_validity_cache_strtab
module: Factor out elf_validity_cache_strtab
module: Group section index calculations together
module: Factor out elf_validity_cache_index_str
module: Factor out elf_validity_cache_index_sym
module: Factor out elf_validity_cache_index_mod
module: Factor out elf_validity_cache_index_info
module: Factor out elf_validity_cache_secstrings
module: Factor out elf_validity_cache_sechdrs
module: Factor out elf_validity_ehdr
module: Take const arg in validate_section_offset
modules: Add missing entry for __ex_table
modules: Ensure 64-bit alignment on __ksymtab_* sections
$(KBUILD_OUTPUT) specifies the output directory of kernel builds.
Use a more generic name, 'output', to better reflect this code hunk in
the context of external module builds.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
'objtree' refers to the top of the output directory of kernel builds.
Rename abs_objtree to a more generic name, to better reflect its use in
the context of external module builds.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
$(objtree) refers to the top of the output directory of kernel builds.
This commit adds the explicit $(objtree)/ prefix to build artifacts
needed for building external modules.
This change has no immediate impact, as the top-level Makefile
currently defines:
objtree := .
This commit prepares for supporting the building of external modules
in a different directory.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
