Commit Graph

2448 Commits

Author SHA1 Message Date
Miguel Ojeda
db4f72c904 rust: enable clippy::undocumented_unsafe_blocks lint
Checking that we are not missing any `// SAFETY` comments in our `unsafe`
blocks is something we have wanted to do for a long time, as well as
cleaning up the remaining cases that were not documented [1].

Back when Rust for Linux started, this was something that could have
been done via a script, like Rust's `tidy`. Soon after, in Rust 1.58.0,
Clippy implemented the `undocumented_unsafe_blocks` lint [2].

Even though the lint has a few false positives, e.g. in some cases where
attributes appear between the comment and the `unsafe` block [3], there
are workarounds and the lint seems quite usable already.

Thus enable the lint now.

We still have a few cases to clean up, so just allow those for the moment
by writing a `TODO` comment -- some of those may be good candidates for
new contributors.

Link: https://github.com/Rust-for-Linux/linux/issues/351 [1]
Link: https://rust-lang.github.io/rust-clippy/master/#/undocumented_unsafe_blocks [2]
Link: https://github.com/rust-lang/rust-clippy/issues/13189 [3]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Tested-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240904204347.168520-5-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-10-07 21:39:05 +02:00
Miguel Ojeda
a135aa3d30 rust: sort global Rust flags
Sort the global Rust flags so that it is easier to follow along when we
have more, like this patch series does.

Reviewed-by: Trevor Gross <tmgross@umich.edu>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240904204347.168520-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-10-07 10:49:15 +02:00
Linus Torvalds
8cf0b93919 Linux 6.12-rc2 2024-10-06 15:32:27 -07:00
Xu Yang
d939881a15 kbuild: fix a typo dt_binding_schema -> dt_binding_schemas
If we follow "make help" to "make dt_binding_schema", we will see
below error:

$ make dt_binding_schema
make[1]: *** No rule to make target 'dt_binding_schema'.  Stop.
make: *** [Makefile:224: __sub-make] Error 2

It should be a typo. So this will fix it.

Fixes: 604a57ba97 ("dt-bindings: kbuild: Add separate target/dependency for processed-schema.json")
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Reviewed-by: Nicolas Schier <n.schier@avm.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-10-07 02:36:38 +09:00
Linus Torvalds
9852d85ec9 Linux 6.12-rc1 2024-09-29 15:06:19 -07:00
Linus Torvalds
5701725692 Rust changes for v6.12
Toolchain and infrastructure:
 
  - Support 'MITIGATION_{RETHUNK,RETPOLINE,SLS}' (which cleans up objtool
    warnings), teach objtool about 'noreturn' Rust symbols and mimic
    '___ADDRESSABLE()' for 'module_{init,exit}'. With that, we should be
    objtool-warning-free, so enable it to run for all Rust object files.
 
  - KASAN (no 'SW_TAGS'), KCFI and shadow call sanitizer support.
 
  - Support 'RUSTC_VERSION', including re-config and re-build on change.
 
  - Split helpers file into several files in a folder, to avoid conflicts
    in it. Eventually those files will be moved to the right places with
    the new build system. In addition, remove the need to manually export
    the symbols defined there, reusing existing machinery for that.
 
  - Relax restriction on configurations with Rust + GCC plugins to just
    the RANDSTRUCT plugin.
 
 'kernel' crate:
 
  - New 'list' module: doubly-linked linked list for use with reference
    counted values, which is heavily used by the upcoming Rust Binder.
    This includes 'ListArc' (a wrapper around 'Arc' that is guaranteed
    unique for the given ID), 'AtomicTracker' (tracks whether a 'ListArc'
    exists using an atomic), 'ListLinks' (the prev/next pointers for an
    item in a linked list), 'List' (the linked list itself), 'Iter' (an
    iterator over a 'List'), 'Cursor' (a cursor into a 'List' that allows
    to remove elements), 'ListArcField' (a field exclusively owned by a
    'ListArc'), as well as support for heterogeneous lists.
 
  - New 'rbtree' module: red-black tree abstractions used by the upcoming
    Rust Binder. This includes 'RBTree' (the red-black tree itself),
    'RBTreeNode' (a node), 'RBTreeNodeReservation' (a memory reservation
    for a node), 'Iter' and 'IterMut' (immutable and mutable iterators),
    'Cursor' (bidirectional cursor that allows to remove elements), as
    well as an entry API similar to the Rust standard library one.
 
  - 'init' module: add 'write_[pin_]init' methods and the 'InPlaceWrite'
    trait. Add the 'assert_pinned!' macro.
 
  - 'sync' module: implement the 'InPlaceInit' trait for 'Arc' by
    introducing an associated type in the trait.
 
  - 'alloc' module: add 'drop_contents' method to 'BoxExt'.
 
  - 'types' module: implement the 'ForeignOwnable' trait for
    'Pin<Box<T>>' and improve the trait's documentation. In addition,
    add the 'into_raw' method to the 'ARef' type.
 
  - 'error' module: in preparation for the upcoming Rust support for
    32-bit architectures, like arm, locally allow Clippy lint for those.
 
 Documentation:
 
  - https://rust.docs.kernel.org has been announced, so link to it.
 
  - Enable rustdoc's "jump to definition" feature, making its output a
    bit closer to the experience in a cross-referencer.
 
  - Debian Testing now also provides recent Rust releases (outside of
    the freeze period), so add it to the list.
 
 MAINTAINERS:
 
  - Trevor is joining as reviewer of the "RUST" entry.
 
 And a few other small bits.
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Merge tag 'rust-6.12' of https://github.com/Rust-for-Linux/linux

Pull Rust updates from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Support 'MITIGATION_{RETHUNK,RETPOLINE,SLS}' (which cleans up
     objtool warnings), teach objtool about 'noreturn' Rust symbols and
     mimic '___ADDRESSABLE()' for 'module_{init,exit}'. With that, we
     should be objtool-warning-free, so enable it to run for all Rust
     object files.

   - KASAN (no 'SW_TAGS'), KCFI and shadow call sanitizer support.

   - Support 'RUSTC_VERSION', including re-config and re-build on
     change.

   - Split helpers file into several files in a folder, to avoid
     conflicts in it. Eventually those files will be moved to the right
     places with the new build system. In addition, remove the need to
     manually export the symbols defined there, reusing existing
     machinery for that.

   - Relax restriction on configurations with Rust + GCC plugins to just
     the RANDSTRUCT plugin.

  'kernel' crate:

   - New 'list' module: doubly-linked linked list for use with reference
     counted values, which is heavily used by the upcoming Rust Binder.

     This includes 'ListArc' (a wrapper around 'Arc' that is guaranteed
     unique for the given ID), 'AtomicTracker' (tracks whether a
     'ListArc' exists using an atomic), 'ListLinks' (the prev/next
     pointers for an item in a linked list), 'List' (the linked list
     itself), 'Iter' (an iterator over a 'List'), 'Cursor' (a cursor
     into a 'List' that allows to remove elements), 'ListArcField' (a
     field exclusively owned by a 'ListArc'), as well as support for
     heterogeneous lists.

   - New 'rbtree' module: red-black tree abstractions used by the
     upcoming Rust Binder.

     This includes 'RBTree' (the red-black tree itself), 'RBTreeNode' (a
     node), 'RBTreeNodeReservation' (a memory reservation for a node),
     'Iter' and 'IterMut' (immutable and mutable iterators), 'Cursor'
     (bidirectional cursor that allows to remove elements), as well as
     an entry API similar to the Rust standard library one.

   - 'init' module: add 'write_[pin_]init' methods and the
     'InPlaceWrite' trait. Add the 'assert_pinned!' macro.

   - 'sync' module: implement the 'InPlaceInit' trait for 'Arc' by
     introducing an associated type in the trait.

   - 'alloc' module: add 'drop_contents' method to 'BoxExt'.

   - 'types' module: implement the 'ForeignOwnable' trait for
     'Pin<Box<T>>' and improve the trait's documentation. In addition,
     add the 'into_raw' method to the 'ARef' type.

   - 'error' module: in preparation for the upcoming Rust support for
     32-bit architectures, like arm, locally allow Clippy lint for
     those.

  Documentation:

   - https://rust.docs.kernel.org has been announced, so link to it.

   - Enable rustdoc's "jump to definition" feature, making its output a
     bit closer to the experience in a cross-referencer.

   - Debian Testing now also provides recent Rust releases (outside of
     the freeze period), so add it to the list.

  MAINTAINERS:

   - Trevor is joining as reviewer of the "RUST" entry.

  And a few other small bits"

* tag 'rust-6.12' of https://github.com/Rust-for-Linux/linux: (54 commits)
  kasan: rust: Add KASAN smoke test via UAF
  kbuild: rust: Enable KASAN support
  rust: kasan: Rust does not support KHWASAN
  kbuild: rust: Define probing macros for rustc
  kasan: simplify and clarify Makefile
  rust: cfi: add support for CFI_CLANG with Rust
  cfi: add CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
  rust: support for shadow call stack sanitizer
  docs: rust: include other expressions in conditional compilation section
  kbuild: rust: replace proc macros dependency on `core.o` with the version text
  kbuild: rust: rebuild if the version text changes
  kbuild: rust: re-run Kconfig if the version text changes
  kbuild: rust: add `CONFIG_RUSTC_VERSION`
  rust: avoid `box_uninit_write` feature
  MAINTAINERS: add Trevor Gross as Rust reviewer
  rust: rbtree: add `RBTree::entry`
  rust: rbtree: add cursor
  rust: rbtree: add mutable iterator
  rust: rbtree: add iterator
  rust: rbtree: add red-black tree implementation backed by the C version
  ...
2024-09-25 10:25:40 -07:00
Linus Torvalds
68e5c7d4ce Kbuild updates for v6.12
- Support cross-compiling linux-headers Debian package and kernel-devel
    RPM package
 
  - Add support for the linux-debug Pacman package
 
  - Improve module rebuilding speed by factoring out the common code to
    scripts/module-common.c
 
  - Separate device tree build rules into scripts/Makefile.dtbs
 
  - Add a new script to generate modules.builtin.ranges, which is useful
    for tracing tools to find symbols in built-in modules
 
  - Refactor Kconfig and misc tools
 
  - Update Kbuild and Kconfig documentation
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Merge tag 'kbuild-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Support cross-compiling linux-headers Debian package and kernel-devel
   RPM package

 - Add support for the linux-debug Pacman package

 - Improve module rebuilding speed by factoring out the common code to
   scripts/module-common.c

 - Separate device tree build rules into scripts/Makefile.dtbs

 - Add a new script to generate modules.builtin.ranges, which is useful
   for tracing tools to find symbols in built-in modules

 - Refactor Kconfig and misc tools

 - Update Kbuild and Kconfig documentation

* tag 'kbuild-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (51 commits)
  kbuild: doc: replace "gcc" in external module description
  kbuild: doc: describe the -C option precisely for external module builds
  kbuild: doc: remove the description about shipped files
  kbuild: doc: drop section numbering, use references in modules.rst
  kbuild: doc: throw out the local table of contents in modules.rst
  kbuild: doc: remove outdated description of the limitation on -I usage
  kbuild: doc: remove description about grepping CONFIG options
  kbuild: doc: update the description about Kbuild/Makefile split
  kbuild: remove unnecessary export of RUST_LIB_SRC
  kbuild: remove append operation on cmd_ld_ko_o
  kconfig: cache expression values
  kconfig: use hash table to reuse expressions
  kconfig: refactor expr_eliminate_dups()
  kconfig: add comments to expression transformations
  kconfig: change some expr_*() functions to bool
  scripts: move hash function from scripts/kconfig/ to scripts/include/
  kallsyms: change overflow variable to bool type
  kallsyms: squash output_address()
  kbuild: add install target for modules.builtin.ranges
  scripts: add verifier script for builtin module range data
  ...
2024-09-24 13:02:06 -07:00
Masahiro Yamada
fc1c79be45 kbuild: remove unnecessary export of RUST_LIB_SRC
If RUST_LIB_SRC is defined in the top-level Makefile (via an environment
variable or command line), it is already exported.

The only situation where it is defined but not exported is when the
top-level Makefile is wrapped by another Makefile (e.g., GNUmakefile).
I cannot think of any other use cases.

I know some people use this tip to define custom variables. However,
even in that case, you can export it directly in the wrapper Makefile.

Example GNUmakefile:

    export RUST_LIB_SRC = /path/to/your/sysroot/lib/rustlib/src/rust/library
    include Makefile

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
2024-09-24 03:06:52 +09:00
Kris Van Hees
5f5e734432 kbuild: generate offset range data for builtin modules
Create file module.builtin.ranges that can be used to find where
built-in modules are located by their addresses. This will be useful for
tracing tools to find what functions are for various built-in modules.

The offset range data for builtin modules is generated using:
 - modules.builtin: associates object files with module names
 - vmlinux.map: provides load order of sections and offset of first member
    per section
 - vmlinux.o.map: provides offset of object file content per section
 - .*.cmd: build cmd file with KBUILD_MODFILE

The generated data will look like:

.text 00000000-00000000 = _text
.text 0000baf0-0000cb10 amd_uncore
.text 0009bd10-0009c8e0 iosf_mbi
...
.text 00b9f080-00ba011a intel_skl_int3472_discrete
.text 00ba0120-00ba03c0 intel_skl_int3472_discrete intel_skl_int3472_tps68470
.text 00ba03c0-00ba08d6 intel_skl_int3472_tps68470
...
.data 00000000-00000000 = _sdata
.data 0000f020-0000f680 amd_uncore

For each ELF section, it lists the offset of the first symbol.  This can
be used to determine the base address of the section at runtime.

Next, it lists (in strict ascending order) offset ranges in that section
that cover the symbols of one or more builtin modules.  Multiple ranges
can apply to a single module, and ranges can be shared between modules.

The CONFIG_BUILTIN_MODULE_RANGES option controls whether offset range data
is generated for kernel modules that are built into the kernel image.

How it works:

 1. The modules.builtin file is parsed to obtain a list of built-in
    module names and their associated object names (the .ko file that
    the module would be in if it were a loadable module, hereafter
    referred to as <kmodfile>).  This object name can be used to
    identify objects in the kernel compile because any C or assembler
    code that ends up into a built-in module will have the option
    -DKBUILD_MODFILE=<kmodfile> present in its build command, and those
    can be found in the .<obj>.cmd file in the kernel build tree.

    If an object is part of multiple modules, they will all be listed
    in the KBUILD_MODFILE option argument.

    This allows us to conclusively determine whether an object in the
    kernel build belong to any modules, and which.

 2. The vmlinux.map is parsed next to determine the base address of each
    top level section so that all addresses into the section can be
    turned into offsets.  This makes it possible to handle sections
    getting loaded at different addresses at system boot.

    We also determine an 'anchor' symbol at the beginning of each
    section to make it possible to calculate the true base address of
    a section at runtime (i.e. symbol address - symbol offset).

    We collect start addresses of sections that are included in the top
    level section.  This is used when vmlinux is linked using vmlinux.o,
    because in that case, we need to look at the vmlinux.o linker map to
    know what object a symbol is found in.

    And finally, we process each symbol that is listed in vmlinux.map
    (or vmlinux.o.map) based on the following structure:

    vmlinux linked from vmlinux.a:

      vmlinux.map:
        <top level section>
          <included section>  -- might be same as top level section)
            <object>          -- built-in association known
              <symbol>        -- belongs to module(s) object belongs to
              ...

    vmlinux linked from vmlinux.o:

      vmlinux.map:
        <top level section>
          <included section>  -- might be same as top level section)
            vmlinux.o         -- need to use vmlinux.o.map
              <symbol>        -- ignored
              ...

      vmlinux.o.map:
        <section>
            <object>          -- built-in association known
              <symbol>        -- belongs to module(s) object belongs to
              ...

 3. As sections, objects, and symbols are processed, offset ranges are
    constructed in a straight-forward way:

      - If the symbol belongs to one or more built-in modules:
          - If we were working on the same module(s), extend the range
            to include this object
          - If we were working on another module(s), close that range,
            and start the new one
      - If the symbol does not belong to any built-in modules:
          - If we were working on a module(s) range, close that range

Signed-off-by: Kris Van Hees <kris.van.hees@oracle.com>
Reviewed-by: Nick Alcock <nick.alcock@oracle.com>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Sam James <sam@gentoo.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-09-20 09:21:43 +09:00
Matthew Maurer
ca627e6365 rust: cfi: add support for CFI_CLANG with Rust
Make it possible to use the Control Flow Integrity (CFI) sanitizer when
Rust is enabled. Enabling CFI with Rust requires that CFI is configured
to normalize integer types so that all integer types of the same size
and signedness are compatible under CFI.

Rust and C use the same LLVM backend for code generation, so Rust KCFI
is compatible with the KCFI used in the kernel for C. In the case of
FineIBT, CFI also depends on -Zpatchable-function-entry for rewriting
the function prologue, so we set that flag for Rust as well. The flag
for FineIBT requires rustc 1.80.0 or later, so include a Kconfig
requirement for that.

Enabling Rust will select CFI_ICALL_NORMALIZE_INTEGERS because the flag
is required to use Rust with CFI. Using select rather than `depends on`
avoids the case where Rust is not visible in menuconfig due to
CFI_ICALL_NORMALIZE_INTEGERS not being enabled. One disadvantage of
select is that RUST must `depends on` all of the things that
CFI_ICALL_NORMALIZE_INTEGERS depends on to avoid invalid configurations.

Alice has been using KCFI on her phone for several months, so it is
reasonably well tested on arm64.

Signed-off-by: Matthew Maurer <mmaurer@google.com>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Gatlin Newhouse <gatlin.newhouse@gmail.com>
Acked-by: Kees Cook <kees@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240801-kcfi-v2-2-c93caed3d121@google.com
[ Replaced `!FINEIBT` requirement with `!CALL_PADDING` to prevent
  a build error on older Rust compilers. Fixed typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-09-16 17:29:58 +02:00
Linus Torvalds
98f7e32f20 Linux 6.11 2024-09-15 16:57:56 +02:00
Alice Ryhl
ce4a262098 cfi: add CONFIG_CFI_ICALL_NORMALIZE_INTEGERS
Introduce a Kconfig option for enabling the experimental option to
normalize integer types. This ensures that integer types of the same
size and signedness are considered compatible by the Control Flow
Integrity sanitizer.

The security impact of this flag is minimal. When Sami Tolvanen looked
into it, he found that integer normalization reduced the number of
unique type hashes in the kernel by ~1%, which is acceptable.

This option exists for compatibility with Rust, as C and Rust do not
have the same set of integer types. There are cases where C has two
different integer types of the same size and signedness, but Rust only
has one integer type of that size and signedness. When Rust calls into
C functions using such types in their signature, this results in CFI
failures. One example is 'unsigned long long' and 'unsigned long' which
are both 64-bit on LP64 targets, so on those targets this flag will give
both types the same CFI tag.

This flag changes the ABI heavily. It is not applied automatically when
CONFIG_RUST is turned on to make sure that the CONFIG_RUST option does
not change the ABI of C code. For example, some build may need to make
other changes atomically with toggling this flag. Having it be a
separate option makes it possible to first turn on normalized integer
tags, and then later turn on CONFIG_RUST.

Similarly, when turning on CONFIG_RUST in a build, you may need a few
attempts where the RUST=y commit gets reverted a few times. It is
inconvenient if reverting RUST=y also requires reverting the changes you
made to support normalized integer tags.

To avoid having this flag impact builds that don't care about this, the
next patch in this series will make CONFIG_RUST turn on this option
using `select` rather than `depends on`.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Gatlin Newhouse <gatlin.newhouse@gmail.com>
Acked-by: Kees Cook <kees@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240801-kcfi-v2-1-c93caed3d121@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-09-13 00:43:55 +02:00
Alice Ryhl
d077242d68 rust: support for shadow call stack sanitizer
Add all of the flags that are needed to support the shadow call stack
(SCS) sanitizer with Rust, and updates Kconfig to allow only
configurations that work.

The -Zfixed-x18 flag is required to use SCS on arm64, and requires rustc
version 1.80.0 or greater. This restriction is reflected in Kconfig.

When CONFIG_DYNAMIC_SCS is enabled, the build will be configured to
include unwind tables in the build artifacts. Dynamic SCS uses the
unwind tables at boot to find all places that need to be patched. The
-Cforce-unwind-tables=y flag ensures that unwind tables are available
for Rust code.

In non-dynamic mode, the -Zsanitizer=shadow-call-stack flag is what
enables the SCS sanitizer. Using this flag requires rustc version 1.82.0
or greater on the targets used by Rust in the kernel. This restriction
is reflected in Kconfig.

It is possible to avoid the requirement of rustc 1.80.0 by using
-Ctarget-feature=+reserve-x18 instead of -Zfixed-x18. However, this flag
emits a warning during the build, so this patch does not add support for
using it and instead requires 1.80.0 or greater.

The dependency is placed on `select HAVE_RUST` to avoid a situation
where enabling Rust silently turns off the sanitizer. Instead, turning
on the sanitizer results in Rust being disabled. We generally do not
want changes to CONFIG_RUST to result in any mitigations being changed
or turned off.

At the time of writing, rustc 1.82.0 only exists via the nightly release
channel. There is a chance that the -Zsanitizer=shadow-call-stack flag
will end up needing 1.83.0 instead, but I think it is small.

Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Kees Cook <kees@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240829-shadow-call-stack-v7-1-2f62a4432abf@google.com
[ Fixed indentation using spaces. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-09-13 00:03:14 +02:00
Linus Torvalds
da3ea35007 Linux 6.11-rc7 2024-09-08 14:50:28 -07:00
Linus Torvalds
6c5b3e30e5 Rust fixes for v6.11 (2nd)
Toolchain and infrastructure:
 
  - Fix builds for nightly compiler users now that 'new_uninit' was split
    into new features by using an alternative approach for the code that
    used what is now called the 'box_uninit_write' feature.
 
  - Allow the 'stable_features' lint to preempt upcoming warnings about
    them, since soon there will be unstable features that will become
    stable in nightly compilers.
 
  - Export bss symbols too.
 
 'kernel' crate:
 
  - 'block' module: fix wrong usage of lockdep API.
 
 'macros' crate:
 
  - Provide correct provenance when constructing 'THIS_MODULE'.
 
 Documentation:
 
  - Remove unintended indentation (blockquotes) in generated output.
 
  - Fix a couple typos.
 
 MAINTAINERS:
 
  - Remove Wedson as Rust maintainer.
 
  - Update Andreas' email.
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Merge tag 'rust-fixes-6.11-2' of https://github.com/Rust-for-Linux/linux

Pull Rust fixes from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Fix builds for nightly compiler users now that 'new_uninit' was
     split into new features by using an alternative approach for the
     code that used what is now called the 'box_uninit_write' feature

   - Allow the 'stable_features' lint to preempt upcoming warnings about
     them, since soon there will be unstable features that will become
     stable in nightly compilers

   - Export bss symbols too

  'kernel' crate:

   - 'block' module: fix wrong usage of lockdep API

  'macros' crate:

   - Provide correct provenance when constructing 'THIS_MODULE'

  Documentation:

   - Remove unintended indentation (blockquotes) in generated output

   - Fix a couple typos

  MAINTAINERS:

   - Remove Wedson as Rust maintainer

   - Update Andreas' email"

* tag 'rust-fixes-6.11-2' of https://github.com/Rust-for-Linux/linux:
  MAINTAINERS: update Andreas Hindborg's email address
  MAINTAINERS: Remove Wedson as Rust maintainer
  rust: macros: provide correct provenance when constructing THIS_MODULE
  rust: allow `stable_features` lint
  docs: rust: remove unintended blockquote in Quick Start
  rust: alloc: eschew `Box<MaybeUninit<T>>::write`
  rust: kernel: fix typos in code comments
  docs: rust: remove unintended blockquote in Coding Guidelines
  rust: block: fix wrong usage of lockdep API
  rust: kbuild: fix export of bss symbols
2024-09-05 16:35:57 -07:00
Miguel Ojeda
5134a335cf kbuild: rust: re-run Kconfig if the version text changes
Re-run Kconfig if we detect the Rust compiler has changed via the version
text, like it is done for C.

Unlike C, and unlike `RUSTC_VERSION`, the `RUSTC_VERSION_TEXT` is kept
under `depends on RUST`, since it should not be needed unless `RUST`
is enabled.

Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20240902165535.1101978-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-09-05 22:44:34 +02:00
Masahiro Yamada
87af9388b4 kbuild: remove *.symversions left-over
Commit 5ce2176b81 ("genksyms: adjust the output format to modpost")
stopped generating *.symversions files.

Remove the left-over from the .gitignore file and the 'clean' rule.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2024-09-01 20:34:50 +09:00
Linus Torvalds
431c1646e1 Linux 6.11-rc6 2024-09-01 19:46:02 +12:00
Miguel Ojeda
8e95e53ca3 rust: allow stable_features lint
Support for several Rust compiler versions started in commit 63b27f4a00
("rust: start supporting several compiler versions"). Since we currently
need to use a number of unstable features in the kernel, it is a matter
of time until one gets stabilized and the `stable_features` lint warns.

For instance, the `new_uninit` feature may become stable soon, which
would give us multiple warnings like the following:

    warning: the feature `new_uninit` has been stable since 1.82.0-dev
    and no longer requires an attribute to enable
      --> rust/kernel/lib.rs:17:12
       |
    17 | #![feature(new_uninit)]
       |            ^^^^^^^^^^
       |
       = note: `#[warn(stable_features)]` on by default

Thus allow the `stable_features` lint to avoid such warnings. This is
the simplest approach -- we do not have that many cases (and the goal
is to stop using unstable features anyway) and cleanups can be easily
done when we decide to update the minimum version.

An alternative would be to conditionally enable them based on the
compiler version (with the upcoming `RUSTC_VERSION` or maybe with the
unstable `cfg(version(...))`, but that one apparently will not work for
the nightly case). However, doing so is more complex and may not work
well for different nightlies of the same version, unless we do not care
about older nightlies.

Another alternative is using explicit tests of the feature calling
`rustc`, but that is also more complex and slower.

Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240827100403.376389-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-08-27 22:50:09 +02:00
Linus Torvalds
5be63fc19f Linux 6.11-rc5 2024-08-25 19:07:11 +12:00
Linus Torvalds
3f44ae972a Kbuild fixes for v6.11 (2nd)
- Eliminate the fdtoverlay command duplication in scripts/Makefile.lib
 
  - Fix 'make compile_commands.json' for external modules
 
  - Ensure scripts/kconfig/merge_config.sh handles missing newlines
 
  - Fix some build errors on macOS
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Merge tag 'kbuild-fixes-v6.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Eliminate the fdtoverlay command duplication in scripts/Makefile.lib

 - Fix 'make compile_commands.json' for external modules

 - Ensure scripts/kconfig/merge_config.sh handles missing newlines

 - Fix some build errors on macOS

* tag 'kbuild-fixes-v6.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: fix typos "prequisites" to "prerequisites"
  Documentation/llvm: turn make command for ccache into code block
  kbuild: avoid scripts/kallsyms parsing /dev/null
  treewide: remove unnecessary <linux/version.h> inclusion
  scripts: kconfig: merge_config: config files: add a trailing newline
  Makefile: add $(srctree) to dependency of compile_commands.json target
  kbuild: clean up code duplication in cmd_fdtoverlay
2024-08-23 07:43:15 +08:00
Linus Torvalds
47ac09b91b Linux 6.11-rc4 2024-08-18 13:17:27 -07:00
Linus Torvalds
60cb1da6ed Rust fixes for v6.11
- Fix '-Os' Rust 1.80.0+ builds adding more intrinsics (also tweaked
    in upstream Rust for the upcoming 1.82.0).
 
  - Fix support for the latest version of rust-analyzer due to a change
    on rust-analyzer config file semantics (considered a fix since most
    developers use the latest version of the tool, which is the only one
    actually supported by upstream). I am discussing stability of the
    config file with upstream -- they may be able to start versioning it.
 
  - Fix GCC 14 builds due to '-fmin-function-alignment' not skipped for
    libclang (bindgen).
 
  - A couple Kconfig fixes around '{RUSTC,BINDGEN}_VERSION_TEXT' to
    suppress error messages in a foreign architecture chroot and to use a
    proper default format.
 
  - Clean 'rust-analyzer' target warning due to missing recursive make
    invocation mark.
 
  - Clean Clippy warning due to missing indentation in docs.
 
  - Clean LLVM 19 build warning due to removed 3dnow feature upstream.
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Merge tag 'rust-fixes-6.11' of https://github.com/Rust-for-Linux/linux

Pull rust fixes from Miguel Ojeda:

 - Fix '-Os' Rust 1.80.0+ builds adding more intrinsics (also tweaked in
   upstream Rust for the upcoming 1.82.0).

 - Fix support for the latest version of rust-analyzer due to a change
   on rust-analyzer config file semantics (considered a fix since most
   developers use the latest version of the tool, which is the only one
   actually supported by upstream). I am discussing stability of the
   config file with upstream -- they may be able to start versioning it.

 - Fix GCC 14 builds due to '-fmin-function-alignment' not skipped for
   libclang (bindgen).

 - A couple Kconfig fixes around '{RUSTC,BINDGEN}_VERSION_TEXT' to
   suppress error messages in a foreign architecture chroot and to use a
   proper default format.

 - Clean 'rust-analyzer' target warning due to missing recursive make
   invocation mark.

 - Clean Clippy warning due to missing indentation in docs.

 - Clean LLVM 19 build warning due to removed 3dnow feature upstream.

* tag 'rust-fixes-6.11' of https://github.com/Rust-for-Linux/linux:
  rust: x86: remove `-3dnow{,a}` from target features
  kbuild: rust-analyzer: mark `rust_is_available.sh` invocation as recursive
  rust: add intrinsics to fix `-Os` builds
  kbuild: rust: skip -fmin-function-alignment in bindgen flags
  rust: Support latest version of `rust-analyzer`
  rust: macros: indent list item in `module!`'s docs
  rust: fix the default format for CONFIG_{RUSTC,BINDGEN}_VERSION_TEXT
  rust: suppress error messages from CONFIG_{RUSTC,BINDGEN}_VERSION_TEXT
2024-08-16 11:24:06 -07:00
Linus Torvalds
7c626ce4ba Linux 6.11-rc3 2024-08-11 14:27:14 -07:00
Miguel Ojeda
d734422b7d kbuild: rust-analyzer: mark rust_is_available.sh invocation as recursive
When calling the `rust_is_available.sh` script, we need to make the
jobserver available to it, as commit ecab4115c4 ("kbuild: mark `rustc`
(and others) invocations as recursive") explains and did for the others.

Otherwise, we get a warning from `rustc` when calling `make rust-analyzer`
with parallel jobs, e.g. `-j8`. Using several jobs for that target does
not really matter, but developers may call `make` with jobs enabled in
all cases.

Thus fix it.

Fixes: 6dc9d9ca9a ("kbuild: rust-analyzer: better error handling")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240806233559.246705-1-ojeda@kernel.org
[ Reworded to add a couple more details mentioned in the list. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-08-10 00:05:10 +02:00
Alexandre Courbot
6fc9aacad4 Makefile: add $(srctree) to dependency of compile_commands.json target
When trying to build compile_commands.json for an external module against
the kernel built in a separate output directory, the following error is
displayed:

  make[1]: *** No rule to make target 'scripts/clang-tools/gen_compile_commands.py',
  needed by 'compile_commands.json'. Stop.

This is because gen_compile_commands.py was previously looked up using a
relative path to $(srctree), but commit b1992c3772 ("kbuild: use
$(src) instead of $(srctree)/$(src) for source directory") stopped
defining VPATH for external module builds.

Prefixing gen_compile_commands.py with $(srctree) fixes the problem.

Fixes: b1992c3772 ("kbuild: use $(src) instead of $(srctree)/$(src) for source directory")
Signed-off-by: Alexandre Courbot <gnurou@gmail.com>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-08-06 14:01:03 +09:00
Linus Torvalds
de9c2c66ad Linux 6.11-rc2 2024-08-04 13:50:53 -07:00
Linus Torvalds
8400291e28 Linux 6.11-rc1 2024-07-28 14:19:55 -07:00
Linus Torvalds
910bfc26d1 Rust changes for v6.11
The highlight is the establishment of a minimum version for the Rust
 toolchain, including 'rustc' (and bundled tools) and 'bindgen'.
 
 The initial minimum will be the pinned version we currently have, i.e.
 we are just widening the allowed versions. That covers 3 stable Rust
 releases: 1.78.0, 1.79.0, 1.80.0 (getting released tomorrow), plus beta,
 plus nightly.
 
 This should already be enough for kernel developers in distributions
 that provide recent Rust compiler versions routinely, such as Arch
 Linux, Debian Unstable (outside the freeze period), Fedora Linux,
 Gentoo Linux (especially the testing channel), Nix (unstable) and
 openSUSE Slowroll and Tumbleweed.
 
 In addition, the kernel is now being built-tested by Rust's pre-merge
 CI. That is, every change that is attempting to land into the Rust
 compiler is tested against the kernel, and it is merged only if it
 passes. Similarly, the bindgen tool has agreed to build the kernel in
 their CI too.
 
 Thus, with the pre-merge CI in place, both projects hope to avoid
 unintentional changes to Rust that break the kernel. This means that,
 in general, apart from intentional changes on their side (that we
 will need to workaround conditionally on our side), the upcoming Rust
 compiler versions should generally work.
 
 In addition, the Rust project has proposed getting the kernel into
 stable Rust (at least solving the main blockers) as one of its three
 flagship goals for 2024H2 [1].
 
 I would like to thank Niko, Sid, Emilio et al. for their help promoting
 the collaboration between Rust and the kernel.
 
 [1] https://rust-lang.github.io/rust-project-goals/2024h2/index.html#flagship-goals
 
 Toolchain and infrastructure:
 
  - Support several Rust toolchain versions.
 
  - Support several bindgen versions.
 
  - Remove 'cargo' requirement and simplify 'rusttest', thanks to 'alloc'
    having been dropped last cycle.
 
  - Provide proper error reporting for the 'rust-analyzer' target.
 
 'kernel' crate:
 
  - Add 'uaccess' module with a safe userspace pointers abstraction.
 
  - Add 'page' module with a 'struct page' abstraction.
 
  - Support more complex generics in workqueue's 'impl_has_work!' macro.
 
 'macros' crate:
 
  - Add 'firmware' field support to the 'module!' macro.
 
  - Improve 'module!' macro documentation.
 
 Documentation:
 
  - Provide instructions on what packages should be installed to build
    the kernel in some popular Linux distributions.
 
  - Introduce the new kernel.org LLVM+Rust toolchains.
 
  - Explain '#[no_std]'.
 
 And a few other small bits.
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Merge tag 'rust-6.11' of https://github.com/Rust-for-Linux/linux

Pull Rust updates from Miguel Ojeda:
 "The highlight is the establishment of a minimum version for the Rust
  toolchain, including 'rustc' (and bundled tools) and 'bindgen'.

  The initial minimum will be the pinned version we currently have, i.e.
  we are just widening the allowed versions. That covers three stable
  Rust releases: 1.78.0, 1.79.0, 1.80.0 (getting released tomorrow),
  plus beta, plus nightly.

  This should already be enough for kernel developers in distributions
  that provide recent Rust compiler versions routinely, such as Arch
  Linux, Debian Unstable (outside the freeze period), Fedora Linux,
  Gentoo Linux (especially the testing channel), Nix (unstable) and
  openSUSE Slowroll and Tumbleweed.

  In addition, the kernel is now being built-tested by Rust's pre-merge
  CI. That is, every change that is attempting to land into the Rust
  compiler is tested against the kernel, and it is merged only if it
  passes. Similarly, the bindgen tool has agreed to build the kernel in
  their CI too.

  Thus, with the pre-merge CI in place, both projects hope to avoid
  unintentional changes to Rust that break the kernel. This means that,
  in general, apart from intentional changes on their side (that we will
  need to workaround conditionally on our side), the upcoming Rust
  compiler versions should generally work.

  In addition, the Rust project has proposed getting the kernel into
  stable Rust (at least solving the main blockers) as one of its three
  flagship goals for 2024H2 [1].

  I would like to thank Niko, Sid, Emilio et al. for their help
  promoting the collaboration between Rust and the kernel.

  Toolchain and infrastructure:

   - Support several Rust toolchain versions.

   - Support several bindgen versions.

   - Remove 'cargo' requirement and simplify 'rusttest', thanks to
     'alloc' having been dropped last cycle.

   - Provide proper error reporting for the 'rust-analyzer' target.

  'kernel' crate:

   - Add 'uaccess' module with a safe userspace pointers abstraction.

   - Add 'page' module with a 'struct page' abstraction.

   - Support more complex generics in workqueue's 'impl_has_work!'
     macro.

  'macros' crate:

   - Add 'firmware' field support to the 'module!' macro.

   - Improve 'module!' macro documentation.

  Documentation:

   - Provide instructions on what packages should be installed to build
     the kernel in some popular Linux distributions.

   - Introduce the new kernel.org LLVM+Rust toolchains.

   - Explain '#[no_std]'.

  And a few other small bits"

Link: https://rust-lang.github.io/rust-project-goals/2024h2/index.html#flagship-goals [1]

* tag 'rust-6.11' of https://github.com/Rust-for-Linux/linux: (26 commits)
  docs: rust: quick-start: add section on Linux distributions
  rust: warn about `bindgen` versions 0.66.0 and 0.66.1
  rust: start supporting several `bindgen` versions
  rust: work around `bindgen` 0.69.0 issue
  rust: avoid assuming a particular `bindgen` build
  rust: start supporting several compiler versions
  rust: simplify Clippy warning flags set
  rust: relax most deny-level lints to warnings
  rust: allow `dead_code` for never constructed bindings
  rust: init: simplify from `map_err` to `inspect_err`
  rust: macros: indent list item in `paste!`'s docs
  rust: add abstraction for `struct page`
  rust: uaccess: add typed accessors for userspace pointers
  uaccess: always export _copy_[from|to]_user with CONFIG_RUST
  rust: uaccess: add userspace pointers
  kbuild: rust-analyzer: improve comment documentation
  kbuild: rust-analyzer: better error handling
  docs: rust: no_std is used
  rust: alloc: add __GFP_HIGHMEM flag
  rust: alloc: fix typo in docs for GFP_NOWAIT
  ...
2024-07-27 13:44:54 -07:00
Linus Torvalds
ca83c61cb3 Kbuild updates for v6.11
- Remove tristate choice support from Kconfig
 
  - Stop using the PROVIDE() directive in the linker script
 
  - Reduce the number of links for the combination of CONFIG_DEBUG_INFO_BTF
    and CONFIG_KALLSYMS
 
  - Enable the warning for symbol reference to .exit.* sections by default
 
  - Fix warnings in RPM package builds
 
  - Improve scripts/make_fit.py to generate a FIT image with separate base
    DTB and overlays
 
  - Improve choice value calculation in Kconfig
 
  - Fix conditional prompt behavior in choice in Kconfig
 
  - Remove support for the uncommon EMAIL environment variable in Debian
    package builds
 
  - Remove support for the uncommon "name <email>" form for the DEBEMAIL
    environment variable
 
  - Raise the minimum supported GNU Make version to 4.0
 
  - Remove stale code for the absolute kallsyms
 
  - Move header files commonly used for host programs to scripts/include/
 
  - Introduce the pacman-pkg target to generate a pacman package used in
    Arch Linux
 
  - Clean up Kconfig
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Merge tag 'kbuild-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Remove tristate choice support from Kconfig

 - Stop using the PROVIDE() directive in the linker script

 - Reduce the number of links for the combination of CONFIG_KALLSYMS and
   CONFIG_DEBUG_INFO_BTF

 - Enable the warning for symbol reference to .exit.* sections by
   default

 - Fix warnings in RPM package builds

 - Improve scripts/make_fit.py to generate a FIT image with separate
   base DTB and overlays

 - Improve choice value calculation in Kconfig

 - Fix conditional prompt behavior in choice in Kconfig

 - Remove support for the uncommon EMAIL environment variable in Debian
   package builds

 - Remove support for the uncommon "name <email>" form for the DEBEMAIL
   environment variable

 - Raise the minimum supported GNU Make version to 4.0

 - Remove stale code for the absolute kallsyms

 - Move header files commonly used for host programs to scripts/include/

 - Introduce the pacman-pkg target to generate a pacman package used in
   Arch Linux

 - Clean up Kconfig

* tag 'kbuild-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (65 commits)
  kbuild: doc: gcc to CC change
  kallsyms: change sym_entry::percpu_absolute to bool type
  kallsyms: unify seq and start_pos fields of struct sym_entry
  kallsyms: add more original symbol type/name in comment lines
  kallsyms: use \t instead of a tab in printf()
  kallsyms: avoid repeated calculation of array size for markers
  kbuild: add script and target to generate pacman package
  modpost: use generic macros for hash table implementation
  kbuild: move some helper headers from scripts/kconfig/ to scripts/include/
  Makefile: add comment to discourage tools/* addition for kernel builds
  kbuild: clean up scripts/remove-stale-files
  kconfig: recursive checks drop file/lineno
  kbuild: rpm-pkg: introduce a simple changelog section for kernel.spec
  kallsyms: get rid of code for absolute kallsyms
  kbuild: Create INSTALL_PATH directory if it does not exist
  kbuild: Abort make on install failures
  kconfig: remove 'e1' and 'e2' macros from expression deduplication
  kconfig: remove SYMBOL_CHOICEVAL flag
  kconfig: add const qualifiers to several function arguments
  kconfig: call expr_eliminate_yn() at least once in expr_eliminate_dups()
  ...
2024-07-23 14:32:21 -07:00
Thomas Weißschuh
c8578539de kbuild: add script and target to generate pacman package
pacman is the package manager used by Arch Linux and its derivates.
Creating native packages from the kernel tree has multiple advantages:

* The package triggers the correct hooks for initramfs generation and
  bootloader configuration
* Uninstallation is complete and also invokes the relevant hooks
* New UAPI headers can be installed without any manual bookkeeping

The PKGBUILD file is a modified version of the one used for the
downstream Arch Linux "linux" package.
Extra steps that should not be necessary for a development kernel have
been removed and an UAPI header package has been added.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-07-22 01:24:22 +09:00
Masahiro Yamada
fbaf242c95 kbuild: move some helper headers from scripts/kconfig/ to scripts/include/
Move array_size.h, hashtable.h, list.h, list_types.h from scripts/kconfig/
to scripts/include/.

These headers will be useful for other host programs.

Remove scripts/mod/list.h.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2024-07-21 23:10:43 +09:00
Masahiro Yamada
6e6ef2da3a Makefile: add comment to discourage tools/* addition for kernel builds
Kbuild provides scripts/Makefile.host to build host programs used for
building the kernel. Unfortunately, there are two exceptions that opt
out of Kbuild. The build system under tools/ is a cheesy replica, and
cause issues. I was recently poked about a problem in the tools build
system, which I do not maintain (and nobody maintains). [1]

Without a comment, people might believe this is the right location
because that is where objtool lives, even if a more robust Kbuild
syntax satisfies their needs. [2]

[1]: https://lore.kernel.org/linux-kbuild/ZnIYWBgrJ-IJtqK8@google.com/T/#m8ece130dd0e23c6f2395ed89070161948dee8457
[2]: https://lore.kernel.org/all/20240618200501.GA1611012@google.com/

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Nicolas Schier <nicolas@fjasle.eu>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
2024-07-20 16:33:45 +09:00
Linus Torvalds
d80f2996b8 asm-generic updates for 6.11
Most of this is part of my ongoing work to clean up the system call
 tables. In this bit, all of the newer architectures are converted to
 use the machine readable syscall.tbl format instead in place of complex
 macros in include/uapi/asm-generic/unistd.h.
 
 This follows an earlier series that fixed various API mismatches
 and in turn is used as the base for planned simplifications.
 
 The other two patches are dead code removal and a warning fix.
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Merge tag 'asm-generic-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic

Pull asm-generic updates from Arnd Bergmann:
 "Most of this is part of my ongoing work to clean up the system call
  tables. In this bit, all of the newer architectures are converted to
  use the machine readable syscall.tbl format instead in place of
  complex macros in include/uapi/asm-generic/unistd.h.

  This follows an earlier series that fixed various API mismatches and
  in turn is used as the base for planned simplifications.

  The other two patches are dead code removal and a warning fix"

* tag 'asm-generic-6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
  vmlinux.lds.h: catch .bss..L* sections into BSS")
  fixmap: Remove unused set_fixmap_offset_io()
  riscv: convert to generic syscall table
  openrisc: convert to generic syscall table
  nios2: convert to generic syscall table
  loongarch: convert to generic syscall table
  hexagon: use new system call table
  csky: convert to generic syscall table
  arm64: rework compat syscall macros
  arm64: generate 64-bit syscall.tbl
  arm64: convert unistd_32.h to syscall.tbl format
  arc: convert to generic syscall table
  clone3: drop __ARCH_WANT_SYS_CLONE3 macro
  kbuild: add syscall table generation to scripts/Makefile.asm-headers
  kbuild: verify asm-generic header list
  loongarch: avoid generating extra header files
  um: don't generate asm/bpf_perf_event.h
  csky: drop asm/gpio.h wrapper
  syscalls: add generic scripts/syscall.tbl
2024-07-16 12:09:03 -07:00
Masahiro Yamada
5f99665ee8 kbuild: raise the minimum GNU Make requirement to 4.0
RHEL/CentOS 7, popular distributions that install GNU Make 3.82, reached
EOM/EOL on June 30, 2024. While you may get extended support, it is a
good time to raise the minimum GNU Make version.

The new requirement, GNU Make 4.0, was released in October, 2013.

I did not touch the Makefiles under tools/ because I do not know the
requirements for building tools. I do not find any GNU Make version
checks under tools/.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
2024-07-16 16:07:14 +09:00
Linus Torvalds
0c38364824 Linux 6.10 2024-07-14 15:43:32 -07:00
Arnd Bergmann
fbb5c0606f kbuild: add syscall table generation to scripts/Makefile.asm-headers
There are 11 copies of arch/*/kernel/syscalls/Makefile that all implement
the same basic logic in a somewhat awkward way.

I tried out various ways of unifying the existing copies and ended up
with something that hooks into the logic for generating the redirections
to asm-generic headers. This gives a nicer syntax of being able to list
the generated files in $(syscall-y) inside of arch/*/include/asm/Kbuild
instead of both $(generated-y) in that place and also in another
Makefile.

The configuration for which syscall.tbl file to use and which ABIs to
enable is now done in arch/*/kernel/Makefile.syscalls. I have done
patches for all architectures and made sure that the new generic
rules implement a superset of all the architecture specific corner
cases.

ince the header file is not specific to asm-generic/*.h redirects
now, I ended up renaming the file to scripts/Makefile.asm-headers.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-07-10 14:23:38 +02:00
Miguel Ojeda
bb421b517e rust: simplify Clippy warning flags set
All Clippy lint groups that we enable, except `correctness`, have a
default `warn` level, thus they may be removed now that we relaxed all
lints to `warn`.

Moreover, Clippy provides an `all` lint group that covers the groups
we enable by default. Thus just use `all` instead -- the only change is
that, if Clippy introduces a new lint group or splits an existing one,
we will cover that one automatically.

In addition, `let_unit_value` is in `style` since Rust 1.62.0, thus it
does not need to be enabled manually.

Reviewed-by: Finn Behrens <me@kloenk.dev>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Andreas Hindborg <a.hindborg@samsung.com>
Link: https://lore.kernel.org/r/20240709160615.998336-6-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-10 10:28:52 +02:00
Miguel Ojeda
f8f88aa25a rust: relax most deny-level lints to warnings
Since we are starting to support several Rust toolchains, lints (including
Clippy ones) now may behave differently and lint groups may include
new lints.

Therefore, to maximize the chances a given version works, relax some
deny-level lints to warnings. It may also make our lives a bit easier
while developing new code or refactoring.

To be clear, the requirements for in-tree code are still the same, since
Rust code still needs to be warning-free (patches should be clean under
`WERROR=y`) and the set of lints is not changed.

`unsafe_op_in_unsafe_fn` is left unmodified, i.e. as an error, since it is
becoming the default in the language (warn-by-default in Rust 2024 [1] and
ideally an error later on) and thus it should also be very well tested. In
addition, it is simple enough that it should not have false positives
(unlike e.g. `rust_2018_idioms`'s `explicit_outlives_requirements`).

`non_ascii_idents` is left unmodified as well, i.e. as an error, since
it is unlikely one gains any productivity during development if it
were a warning (in fact, it may be worse, since it is likely one made
a typo). In addition, it should not have false positives.

Finally, put the two `-D` ones at the top and take the chance to do one
per line.

Link: https://github.com/rust-lang/rust/pull/112038 [1]
Reviewed-by: Finn Behrens <me@kloenk.dev>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Andreas Hindborg <a.hindborg@samsung.com>
Link: https://lore.kernel.org/r/20240709160615.998336-5-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-10 10:28:51 +02:00
John Hubbard
5045b46084 kbuild: rust-analyzer: improve comment documentation
Replace the cryptic phrase ("IDE support targets") that initially
appears to be about how to support old hard drives, with a few sentences
that explain what "make rust-analyzer" provides.

Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Finn Behrens <me@kloenk.dev>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240628004356.1384486-3-jhubbard@nvidia.com
[ Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-08 23:44:01 +02:00
John Hubbard
6dc9d9ca9a kbuild: rust-analyzer: better error handling
1) Provide a better error message for the "Rust not available" case.
Without this patch, one gets various misleading messages, such as:

    "No rule to make target 'rust-analyzer'"

Instead, run scripts/rust_is_available.sh directly, as a prerequisite,
and let that script report the cause of any problems, as well as
providing a link to the documentation. Thanks to Miguel Ojeda for the
idea of just letting rust_is_available.sh report its results directly.

The new output in the failure case looks like this:

$ make rust-analyzer
***
*** Rust compiler 'rustc' could not be found.
***
***
*** Please see Documentation/rust/quick-start.rst for details
*** on how to set up the Rust support.
***
make[1]: *** [/kernel_work/linux-github/Makefile:1975: rust-analyzer] Error 1
make: *** [Makefile:240: __sub-make] Error 2

Reviewed-by: Finn Behrens <me@kloenk.dev>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Link: https://lore.kernel.org/r/20240628004356.1384486-2-jhubbard@nvidia.com
[ Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-08 23:44:01 +02:00
Miguel Ojeda
9ffc80c819 kbuild: rust: remove now-unneeded rusttest custom sysroot handling
Since we dropped our custom `alloc` in commit 9d0441bab7 ("rust: alloc:
remove our fork of the `alloc` crate"), there is no need anymore to keep
the custom sysroot hack.

Thus delete it, which makes the target way simpler and faster too.

This also means we are not using Cargo for anything at the moment,
and that no download is required anymore, so update the main `Makefile`
and the documentation accordingly.

Link: https://lore.kernel.org/r/20240528163502.411600-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-07-08 22:39:39 +02:00
Linus Torvalds
256abd8e55 Linux 6.10-rc7 2024-07-07 14:23:46 -07:00
Linus Torvalds
22a40d14b5 Linux 6.10-rc6 2024-06-30 14:40:44 -07:00
Linus Torvalds
f2661062f1 Linux 6.10-rc5 2024-06-23 17:08:54 -04:00
Linus Torvalds
6ba59ff422 Linux 6.10-rc4 2024-06-16 13:40:16 -07:00
Linus Torvalds
83a7eefedc Linux 6.10-rc3 2024-06-09 14:19:43 -07:00
Linus Torvalds
c3f38fa61a Linux 6.10-rc2 2024-06-02 15:44:56 -07:00
Linus Torvalds
1613e604df Linux 6.10-rc1 2024-05-26 15:20:12 -07:00
Samuel Holland
6cbd1d6d36 arch: add ARCH_HAS_KERNEL_FPU_SUPPORT
Several architectures provide an API to enable the FPU and run
floating-point SIMD code in kernel space.  However, the function names,
header locations, and semantics are inconsistent across architectures, and
FPU support may be gated behind other Kconfig options.

provide a standard way for architectures to declare that kernel space
FPU support is available. Architectures selecting this option must
implement what is currently the most common API (kernel_fpu_begin() and
kernel_fpu_end(), plus a new function kernel_fpu_available()) and
provide the appropriate CFLAGS for compiling floating-point C code.

Link: https://lkml.kernel.org/r/20240329072441.591471-2-samuel.holland@sifive.com
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian König <christian.koenig@amd.com> 
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Xuerui <git@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-05-19 14:36:17 -07:00