bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly

bpf, kconfig: Fix DEBUG_INFO_BTF_MODULES Kconfig definition

[ Upstream commit 229087f6f1dc2d0c38feba805770f28529980ec0 ]

Turns out that due to CONFIG_DEBUG_INFO_BTF_MODULES not having an
explicitly specified "menu item name" in Kconfig, it's basically
impossible to turn it off (see [0]).

This patch fixes the issue by defining menu name for
CONFIG_DEBUG_INFO_BTF_MODULES, which makes it actually adjustable
and independent of CONFIG_DEBUG_INFO_BTF, in the sense that one can
have DEBUG_INFO_BTF=y and DEBUG_INFO_BTF_MODULES=n.

We still keep it as defaulting to Y, of course.

Fixes: 5f9ae91f7c0d ("kbuild: Build kernel module BTFs if BTF is enabled and pahole supports it")
Reported-by: Vincent Li <vincent.mc.li@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/CAK3+h2xiFfzQ9UXf56nrRRP=p1+iUxGoEP5B+aq9MDT5jLXDSg@mail.gmail.com [0]
Link: https://lore.kernel.org/bpf/20240404220344.3879270-1-andrii@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>

show more ...

lib/Kconfig.debug: TEST_IOV_ITER depends on MMU

commit 1eb1e984379e2da04361763f66eec90dd75cf63e upstream.

Trying to run the iov_iter unit test on a nommu system such as the qemu
kc705-nommu emulati

lib/Kconfig.debug: TEST_IOV_ITER depends on MMU

commit 1eb1e984379e2da04361763f66eec90dd75cf63e upstream.

Trying to run the iov_iter unit test on a nommu system such as the qemu
kc705-nommu emulation results in a crash.

KTAP version 1
# Subtest: iov_iter
# module: kunit_iov_iter
1..9
BUG: failure at mm/nommu.c:318/vmap()!
Kernel panic - not syncing: BUG!

The test calls vmap() directly, but vmap() is not supported on nommu
systems, causing the crash. TEST_IOV_ITER therefore needs to depend on
MMU.

Link: https://lkml.kernel.org/r/20240208153010.1439753-1-linux@roeck-us.net
Fixes: 2d71340ff1d4 ("iov_iter: Kunit tests for copying to/from an iterator")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: David Howells <dhowells@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

cred: get rid of CONFIG_DEBUG_CREDENTIALS

commit ae1914174a63a558113e80d24ccac2773f9f7b2b upstream.

This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's

cred: get rid of CONFIG_DEBUG_CREDENTIALS

commit ae1914174a63a558113e80d24ccac2773f9f7b2b upstream.

This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.

Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

iov_iter: Kunit tests for copying to/from an iterator

Add some kunit tests for page extraction for ITER_BVEC, ITER_KVEC and
ITER_XARRAY type iterators. ITER_UBUF and ITER_IOVEC aren't dealt with
as

iov_iter: Kunit tests for copying to/from an iterator

Add some kunit tests for page extraction for ITER_BVEC, ITER_KVEC and
ITER_XARRAY type iterators. ITER_UBUF and ITER_IOVEC aren't dealt with
as they require userspace VM interaction. ITER_DISCARD isn't dealt with
either as that does nothing.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: David Hildenbrand <david@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V

When building for ARCH=riscv using LLVM < 14, there is an error with
CONFIG_DEBUG_INFO_SPLIT=y:

error: A dwo section may not contain reloca

lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V

When building for ARCH=riscv using LLVM < 14, there is an error with
CONFIG_DEBUG_INFO_SPLIT=y:

error: A dwo section may not contain relocations

This was worked around in LLVM 15 by disallowing '-gsplit-dwarf' with
'-mrelax' (the default), so CONFIG_DEBUG_INFO_SPLIT is not selectable
with newer versions of LLVM:

$ clang --target=riscv64-linux-gnu -gsplit-dwarf -c -o /dev/null -x c /dev/null
clang: error: -gsplit-dwarf is unsupported with RISC-V linker relaxation (-mrelax)

GCC silently had a similar issue that was resolved with GCC 12.x.
Restrict CONFIG_DEBUG_INFO_SPLIT for RISC-V when using LLVM or GCC <
12.x to avoid these known issues.

Link: https://github.com/ClangBuiltLinux/linux/issues/1914
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99090
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/all/202308090204.9yZffBWo-lkp@intel.com/
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Fangrui Song <maskray@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20230816-riscv-debug_info_split-v1-1-d1019d6ccc11@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

show more ...

riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B

Allow to force all function address 64B aligned as it is possible for
other architectures. This may be useful when verify if performance
bump is caused b

riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B

Allow to force all function address 64B aligned as it is possible for
other architectures. This may be useful when verify if performance
bump is caused by function alignment changes.

Before commit 1bf18da62106 ("lib/Kconfig.debug: add ARCH dependency
for FUNCTION_ALIGN option"), riscv supports enabling the
DEBUG_FORCE_FUNCTION_ALIGN_64B option, but after that commit, each
arch needs to claim the support explicitly.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230727160356.3874-1-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

show more ...

hardening: Move BUG_ON_DATA_CORRUPTION to hardening options

BUG_ON_DATA_CORRUPTION is turning detected corruptions of list data
structures from WARNings into BUGs. This can be useful to stop further

hardening: Move BUG_ON_DATA_CORRUPTION to hardening options

BUG_ON_DATA_CORRUPTION is turning detected corruptions of list data
structures from WARNings into BUGs. This can be useful to stop further
corruptions or even exploitation attempts.

However, the option has less to do with debugging than with hardening.
With the introduction of LIST_HARDENED, it makes more sense to move it
to the hardening options, where it selects LIST_HARDENED instead.

Without this change, combining BUG_ON_DATA_CORRUPTION with LIST_HARDENED
alone wouldn't be possible, because DEBUG_LIST would always be selected
by BUG_ON_DATA_CORRUPTION.

Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20230811151847.1594958-4-elver@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>

show more ...

list: Introduce CONFIG_LIST_HARDENED

Numerous production kernel configs (see [1, 2]) are choosing to enable
CONFIG_DEBUG_LIST, which is also being recommended by KSPP for hardened
configs [3]. The m

list: Introduce CONFIG_LIST_HARDENED

Numerous production kernel configs (see [1, 2]) are choosing to enable
CONFIG_DEBUG_LIST, which is also being recommended by KSPP for hardened
configs [3]. The motivation behind this is that the option can be used
as a security hardening feature (e.g. CVE-2019-2215 and CVE-2019-2025
are mitigated by the option [4]).

The feature has never been designed with performance in mind, yet common
list manipulation is happening across hot paths all over the kernel.

Introduce CONFIG_LIST_HARDENED, which performs list pointer checking
inline, and only upon list corruption calls the reporting slow path.

To generate optimal machine code with CONFIG_LIST_HARDENED:

1. Elide checking for pointer values which upon dereference would
result in an immediate access fault (i.e. minimal hardening
checks). The trade-off is lower-quality error reports.

2. Use the __preserve_most function attribute (available with Clang,
but not yet with GCC) to minimize the code footprint for calling
the reporting slow path. As a result, function size of callers is
reduced by avoiding saving registers before calling the rarely
called reporting slow path.

Note that all TUs in lib/Makefile already disable function tracing,
including list_debug.c, and __preserve_most's implied notrace has
no effect in this case.

3. Because the inline checks are a subset of the full set of checks in
__list_*_valid_or_report(), always return false if the inline
checks failed. This avoids redundant compare and conditional
branch right after return from the slow path.

As a side-effect of the checks being inline, if the compiler can prove
some condition to always be true, it can completely elide some checks.

Since DEBUG_LIST is functionally a superset of LIST_HARDENED, the
Kconfig variables are changed to reflect that: DEBUG_LIST selects
LIST_HARDENED, whereas LIST_HARDENED itself has no dependency on
DEBUG_LIST.

Running netperf with CONFIG_LIST_HARDENED (using a Clang compiler with
"preserve_most") shows throughput improvements, in my case of ~7% on
average (up to 20-30% on some test cases).

Link: https://r.android.com/1266735 [1]
Link: https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/blob/main/config [2]
Link: https://kernsec.org/wiki/index.php/Kernel_Self_Protection_Project/Recommended_Settings [3]
Link: https://googleprojectzero.blogspot.com/2019/11/bad-binder-android-in-wild-exploit.html [4]
Signed-off-by: Marco Elver <elver@google.com>
Link: https://lore.kernel.org/r/20230811151847.1594958-3-elver@google.com
Signed-off-by: Kees Cook <keescook@chromium.org>

show more ...

kunit: memcpy: Mark tests as slow using test attributes

Mark slow memcpy KUnit tests using test attributes.

Tests marked as slow are as follows: memcpy_large_test, memmove_test,
memmove_large_test,

kunit: memcpy: Mark tests as slow using test attributes

Mark slow memcpy KUnit tests using test attributes.

Tests marked as slow are as follows: memcpy_large_test, memmove_test,
memmove_large_test, and memmove_overlap_test. These tests were the slowest
of the memcpy tests and relatively slower to most other KUnit tests. Most
of these tests are already skipped when CONFIG_MEMCPY_SLOW_KUNIT_TEST is
not enabled.

These tests can now be filtered using the KUnit test attribute filtering
feature. Example: --filter "speed>slow". This will run only the tests that
have speeds faster than slow. The slow attribute will also be outputted in
KTAP.

Note: This patch is intended to replace the use of
CONFIG_MEMCPY_SLOW_KUNIT_TEST and to potentially deprecate this feature.
This patch does not remove the config option but does add a note to the
config definition commenting on this future shift.

Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Rae Moar <rmoar@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

show more ...

rust: support running Rust documentation tests as KUnit ones

Rust has documentation tests: these are typically examples of
usage of any item (e.g. function, struct, module...).

They are very conven

rust: support running Rust documentation tests as KUnit ones

Rust has documentation tests: these are typically examples of
usage of any item (e.g. function, struct, module...).

They are very convenient because they are just written
alongside the documentation. For instance:

/// Sums two numbers.
///
/// ```
/// assert_eq!(mymod::f(10, 20), 30);
/// ```
pub fn f(a: i32, b: i32) -> i32 {
a + b
}

In userspace, the tests are collected and run via `rustdoc`.
Using the tool as-is would be useful already, since it allows
to compile-test most tests (thus enforcing they are kept
in sync with the code they document) and run those that do not
depend on in-kernel APIs.

However, by transforming the tests into a KUnit test suite,
they can also be run inside the kernel. Moreover, the tests
get to be compiled as other Rust kernel objects instead of
targeting userspace.

On top of that, the integration with KUnit means the Rust
support gets to reuse the existing testing facilities. For
instance, the kernel log would look like:

KTAP version 1
1..1
KTAP version 1
# Subtest: rust_doctests_kernel
1..59
# rust_doctest_kernel_build_assert_rs_0.location: rust/kernel/build_assert.rs:13
ok 1 rust_doctest_kernel_build_assert_rs_0
# rust_doctest_kernel_build_assert_rs_1.location: rust/kernel/build_assert.rs:56
ok 2 rust_doctest_kernel_build_assert_rs_1
# rust_doctest_kernel_init_rs_0.location: rust/kernel/init.rs:122
ok 3 rust_doctest_kernel_init_rs_0
...
# rust_doctest_kernel_types_rs_2.location: rust/kernel/types.rs:150
ok 59 rust_doctest_kernel_types_rs_2
# rust_doctests_kernel: pass:59 fail:0 skip:0 total:59
# Totals: pass:59 fail:0 skip:0 total:59
ok 1 rust_doctests_kernel

Therefore, add support for running Rust documentation tests
in KUnit. Some other notes about the current implementation
and support follow.

The transformation is performed by a couple scripts written
as Rust hostprogs.

Tests using the `?` operator are also supported as usual, e.g.:

/// ```
/// # use kernel::{spawn_work_item, workqueue};
/// spawn_work_item!(workqueue::system(), || pr_info!("x"))?;
/// # Ok::<(), Error>(())
/// ```

The tests are also compiled with Clippy under `CLIPPY=1`, just
like normal code, thus also benefitting from extra linting.

The names of the tests are currently automatically generated.
This allows to reduce the burden for documentation writers,
while keeping them fairly stable for bisection. This is an
improvement over the `rustdoc`-generated names, which include
the line number; but ideally we would like to get `rustdoc` to
provide the Rust item path and a number (for multiple examples
in a single documented Rust item).

In order for developers to easily see from which original line
a failed doctests came from, a KTAP diagnostic line is printed
to the log, containing the location (file and line) of the
original test (i.e. instead of the location in the generated
Rust file):

# rust_doctest_kernel_types_rs_2.location: rust/kernel/types.rs:150

This line follows the syntax for declaring test metadata in the
proposed KTAP v2 spec [1], which may be used for the proposed
KUnit test attributes API [2]. Thus hopefully this will make
migration easier later on (suggested by David [3]).

The original line in that test attribute is figured out by
providing an anchor (suggested by Boqun [4]). The original file
is found by walking the filesystem, checking directory prefixes
to reduce the amount of combinations to check, and it is only
done once per file. Ambiguities are detected and reported.

A notable difference from KUnit C tests is that the Rust tests
appear to assert using the usual `assert!` and `assert_eq!`
macros from the Rust standard library (`core`). We provide
a custom version that forwards the call to KUnit instead.
Importantly, these macros do not require passing context,
unlike the KUnit C ones (i.e. `struct kunit *`). This makes
them easier to use, and readers of the documentation do not need
to care about which testing framework is used. In addition, it
may allow us to test third-party code more easily in the future.

However, a current limitation is that KUnit does not support
assertions in other tasks. Thus we presently simply print an
error to the kernel log if an assertion actually failed. This
should be revisited to properly fail the test, perhaps saving
the context somewhere else, or letting KUnit handle it.

Link: https://lore.kernel.org/lkml/20230420205734.1288498-1-rmoar@google.com/ [1]
Link: https://lore.kernel.org/linux-kselftest/20230707210947.1208717-1-rmoar@google.com/ [2]
Link: https://lore.kernel.org/rust-for-linux/CABVgOSkOLO-8v6kdAGpmYnZUb+LKOX0CtYCo-Bge7r_2YTuXDQ@mail.gmail.com/ [3]
Link: https://lore.kernel.org/rust-for-linux/ZIps86MbJF%2FiGIzd@boqun-archlinux/ [4]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

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workqueue: Fix cpu_intensive_thresh_us name in help text

There exists no parameter called "cpu_intensive_threshold_us".
The actual parameter name is "cpu_intensive_thresh_us".

Fixes: 63638450052021

workqueue: Fix cpu_intensive_thresh_us name in help text

There exists no parameter called "cpu_intensive_threshold_us".
The actual parameter name is "cpu_intensive_thresh_us".

Fixes: 6363845005202148 ("workqueue: Report work funcs that trigger automatic CPU_INTENSIVE mechanism")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

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Revert "fortify: Allow KUnit test to build without FORTIFY"

This reverts commit a9dc8d0442294b426b1ebd4ec6097c82ebe282e0.

The standard for KUnit is to not build tests at all when required
functiona

Revert "fortify: Allow KUnit test to build without FORTIFY"

This reverts commit a9dc8d0442294b426b1ebd4ec6097c82ebe282e0.

The standard for KUnit is to not build tests at all when required
functionality is missing, rather than doing test "skip". Restore this
for the fortify tests, so that architectures without
CONFIG_ARCH_HAS_FORTIFY_SOURCE do not emit unsolvable warnings.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Closes: https://lore.kernel.org/all/CAMuHMdUrxOEroHVUt7-mAnKSBjY=a-D3jr+XiAifuwv06Ob9Pw@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>

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watchdog/hardlockup: fix typo in config HARDLOCKUP_DETECTOR_PREFER_BUDDY

Commit a5fcc2367e22 ("watchdog/hardlockup: make HAVE_NMI_WATCHDOG
sparc64-specific") accidentially introduces a typo in one o

watchdog/hardlockup: fix typo in config HARDLOCKUP_DETECTOR_PREFER_BUDDY

Commit a5fcc2367e22 ("watchdog/hardlockup: make HAVE_NMI_WATCHDOG
sparc64-specific") accidentially introduces a typo in one of the config
dependencies of HARDLOCKUP_DETECTOR_PREFER_BUDDY.

Fix this accidental typo.

Link: https://lkml.kernel.org/r/20230623040717.8645-1-lukas.bulwahn@gmail.com
Fixes: a5fcc2367e22 ("watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific")
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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watchdog/hardlockup: define HARDLOCKUP_DETECTOR_ARCH

The HAVE_ prefix means that the code could be enabled. Add another
variable for HAVE_HARDLOCKUP_DETECTOR_ARCH without this prefix.
It will be set

watchdog/hardlockup: define HARDLOCKUP_DETECTOR_ARCH

The HAVE_ prefix means that the code could be enabled. Add another
variable for HAVE_HARDLOCKUP_DETECTOR_ARCH without this prefix.
It will be set when it should be built. It will make it compatible
with the other hardlockup detectors.

The change allows to clean up dependencies of PPC_WATCHDOG
and HAVE_HARDLOCKUP_DETECTOR_PERF definitions for powerpc.

As a result HAVE_HARDLOCKUP_DETECTOR_PERF has the same dependencies
on arm, x86, powerpc architectures.

Link: https://lkml.kernel.org/r/20230616150618.6073-7-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64

The HAVE_ prefix means that the code could be enabled. Add another
variable for HAVE_HARDLOCKUP_DETECTOR_SPARC64 without this prefix.
It will be

watchdog/sparc64: define HARDLOCKUP_DETECTOR_SPARC64

The HAVE_ prefix means that the code could be enabled. Add another
variable for HAVE_HARDLOCKUP_DETECTOR_SPARC64 without this prefix.
It will be set when it should be built. It will make it compatible
with the other hardlockup detectors.

Before, it is far from obvious that the SPARC64 variant is actually used:

$> make ARCH=sparc64 defconfig
$> grep HARDLOCKUP_DETECTOR .config
CONFIG_HAVE_HARDLOCKUP_DETECTOR_BUDDY=y
CONFIG_HAVE_HARDLOCKUP_DETECTOR_SPARC64=y

After, it is more clear:

$> make ARCH=sparc64 defconfig
$> grep HARDLOCKUP_DETECTOR .config
CONFIG_HAVE_HARDLOCKUP_DETECTOR_BUDDY=y
CONFIG_HAVE_HARDLOCKUP_DETECTOR_SPARC64=y
CONFIG_HARDLOCKUP_DETECTOR_SPARC64=y

Link: https://lkml.kernel.org/r/20230616150618.6073-6-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

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watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific

There are several hardlockup detector implementations and several Kconfig
values which allow selection and build of the preferred one.

C

watchdog/hardlockup: make HAVE_NMI_WATCHDOG sparc64-specific

There are several hardlockup detector implementations and several Kconfig
values which allow selection and build of the preferred one.

CONFIG_HARDLOCKUP_DETECTOR was introduced by the commit 23637d477c1f53acb
("lockup_detector: Introduce CONFIG_HARDLOCKUP_DETECTOR") in v2.6.36.
It was a preparation step for introducing the new generic perf hardlockup
detector.

The existing arch-specific variants did not support the to-be-created
generic build configurations, sysctl interface, etc. This distinction
was made explicit by the commit 4a7863cc2eb5f98 ("x86, nmi_watchdog:
Remove ARCH_HAS_NMI_WATCHDOG and rely on CONFIG_HARDLOCKUP_DETECTOR")
in v2.6.38.

CONFIG_HAVE_NMI_WATCHDOG was introduced by the commit d314d74c695f967e105
("nmi watchdog: do not use cpp symbol in Kconfig") in v3.4-rc1. It replaced
the above mentioned ARCH_HAS_NMI_WATCHDOG. At that time, it was still used
by three architectures, namely blackfin, mn10300, and sparc.

The support for blackfin and mn10300 architectures has been completely
dropped some time ago. And sparc is the only architecture with the historic
NMI watchdog at the moment.

And the old sparc implementation is really special. It is always built on
sparc64. It used to be always enabled until the commit 7a5c8b57cec93196b
("sparc: implement watchdog_nmi_enable and watchdog_nmi_disable") added
in v4.10-rc1.

There are only few locations where the sparc64 NMI watchdog interacts
with the generic hardlockup detectors code:

+ implements arch_touch_nmi_watchdog() which is called from the generic
touch_nmi_watchdog()

+ implements watchdog_hardlockup_enable()/disable() to support
/proc/sys/kernel/nmi_watchdog

+ is always preferred over other generic watchdogs, see
CONFIG_HARDLOCKUP_DETECTOR

+ includes asm/nmi.h into linux/nmi.h because some sparc-specific
functions are needed in sparc-specific code which includes
only linux/nmi.h.

The situation became more complicated after the commit 05a4a95279311c3
("kernel/watchdog: split up config options") and commit 2104180a53698df5
("powerpc/64s: implement arch-specific hardlockup watchdog") in v4.13-rc1.
They introduced HAVE_HARDLOCKUP_DETECTOR_ARCH. It was used for powerpc
specific hardlockup detector. It was compatible with the perf one
regarding the general boot, sysctl, and programming interfaces.

HAVE_HARDLOCKUP_DETECTOR_ARCH was defined as a superset of
HAVE_NMI_WATCHDOG. It made some sense because all arch-specific
detectors had some common requirements, namely:

+ implemented arch_touch_nmi_watchdog()
+ included asm/nmi.h into linux/nmi.h
+ defined the default value for /proc/sys/kernel/nmi_watchdog

But it actually has made things pretty complicated when the generic
buddy hardlockup detector was added. Before the generic perf detector
was newer supported together with an arch-specific one. But the buddy
detector could work on any SMP system. It means that an architecture
could support both the arch-specific and buddy detector.

As a result, there are few tricky dependencies. For example,
CONFIG_HARDLOCKUP_DETECTOR depends on:

((HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_BUDDY) && !HAVE_NMI_WATCHDOG) || HAVE_HARDLOCKUP_DETECTOR_ARCH

The problem is that the very special sparc implementation is defined as:

HAVE_NMI_WATCHDOG && !HAVE_HARDLOCKUP_DETECTOR_ARCH

Another problem is that the meaning of HAVE_NMI_WATCHDOG is far from clear
without reading understanding the history.

Make the logic less tricky and more self-explanatory by making
HAVE_NMI_WATCHDOG specific for the sparc64 implementation. And rename it to
HAVE_HARDLOCKUP_DETECTOR_SPARC64.

Note that HARDLOCKUP_DETECTOR_PREFER_BUDDY, HARDLOCKUP_DETECTOR_PERF,
and HARDLOCKUP_DETECTOR_BUDDY may conflict only with
HAVE_HARDLOCKUP_DETECTOR_ARCH. They depend on HARDLOCKUP_DETECTOR
and it is not longer enabled when HAVE_NMI_WATCHDOG is set.

Link: https://lkml.kernel.org/r/20230616150618.6073-5-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

watchdog/hardlockup: make the config checks more straightforward

There are four possible variants of hardlockup detectors:

+ buddy: available when SMP is set.

+ perf: available when HAVE_HARDL

watchdog/hardlockup: make the config checks more straightforward

There are four possible variants of hardlockup detectors:

+ buddy: available when SMP is set.

+ perf: available when HAVE_HARDLOCKUP_DETECTOR_PERF is set.

+ arch-specific: available when HAVE_HARDLOCKUP_DETECTOR_ARCH is set.

+ sparc64 special variant: available when HAVE_NMI_WATCHDOG is set
and HAVE_HARDLOCKUP_DETECTOR_ARCH is not set.

The check for the sparc64 variant is more complicated because
HAVE_NMI_WATCHDOG is used to #ifdef code used by both arch-specific
and sparc64 specific variant. Therefore it is automatically
selected with HAVE_HARDLOCKUP_DETECTOR_ARCH.

This complexity is partly hidden in HAVE_HARDLOCKUP_DETECTOR_NON_ARCH.
It reduces the size of some checks but it makes them harder to follow.

Finally, the other temporary variable HARDLOCKUP_DETECTOR_NON_ARCH
is used to re-compute HARDLOCKUP_DETECTOR_PERF/BUDDY when the global
HARDLOCKUP_DETECTOR switch is enabled/disabled.

Make the logic more straightforward by the following changes:

+ Better explain the role of HAVE_HARDLOCKUP_DETECTOR_ARCH and
HAVE_NMI_WATCHDOG in comments.

+ Add HAVE_HARDLOCKUP_DETECTOR_BUDDY so that there is separate
HAVE_* for all four hardlockup detector variants.

Use it in the other conditions instead of SMP. It makes it
clear that it is about the buddy detector.

+ Open code HAVE_HARDLOCKUP_DETECTOR_NON_ARCH in HARDLOCKUP_DETECTOR
and HARDLOCKUP_DETECTOR_PREFER_BUDDY. It helps to understand
the conditions between the four hardlockup detector variants.

+ Define the exact conditions when HARDLOCKUP_DETECTOR_PERF/BUDDY
can be enabled. It explains the dependency on the other
hardlockup detector variants.

Also it allows to remove HARDLOCKUP_DETECTOR_NON_ARCH by using "imply".
It triggers re-evaluating HARDLOCKUP_DETECTOR_PERF/BUDDY when
the global HARDLOCKUP_DETECTOR switch is changed.

+ Add dependency on HARDLOCKUP_DETECTOR so that the affected variables
disappear when the hardlockup detectors are disabled.

Another nice side effect is that HARDLOCKUP_DETECTOR_PREFER_BUDDY
value is not preserved when the global switch is disabled.
The user has to make the decision again when it gets re-enabled.

Link: https://lkml.kernel.org/r/20230616150618.6073-3-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

watchdog/hardlockup: sort hardlockup detector related config values a logical way

Patch series "watchdog/hardlockup: Cleanup configuration of hardlockup
detectors", v2.

Clean up watchdog Kconfig af

watchdog/hardlockup: sort hardlockup detector related config values a logical way

Patch series "watchdog/hardlockup: Cleanup configuration of hardlockup
detectors", v2.

Clean up watchdog Kconfig after introducing the buddy detector.


This patch (of 6):

There are four possible variants of hardlockup detectors:

+ buddy: available when SMP is set.

+ perf: available when HAVE_HARDLOCKUP_DETECTOR_PERF is set.

+ arch-specific: available when HAVE_HARDLOCKUP_DETECTOR_ARCH is set.

+ sparc64 special variant: available when HAVE_NMI_WATCHDOG is set
and HAVE_HARDLOCKUP_DETECTOR_ARCH is not set.

Only one hardlockup detector can be compiled in. The selection is done
using quite complex dependencies between several CONFIG variables.
The following patches will try to make it more straightforward.

As a first step, reorder the definitions of the various CONFIG variables.
The logical order is:

1. HAVE_* variables define available variants. They are typically
defined in the arch/ config files.

2. HARDLOCKUP_DETECTOR y/n variable defines whether the hardlockup
detector is enabled at all.

3. HARDLOCKUP_DETECTOR_PREFER_BUDDY y/n variable defines whether
the buddy detector should be preferred over the perf one.
Note that the arch specific variants are always preferred when
available.

4. HARDLOCKUP_DETECTOR_PERF/BUDDY variables define whether the given
detector is enabled in the end.

5. HAVE_HARDLOCKUP_DETECTOR_NON_ARCH and HARDLOCKUP_DETECTOR_NON_ARCH
are temporary variables that are going to be removed in
a followup patch.

This is a preparation step for further cleanup. It will change the logic
without shuffling the definitions.

This change temporary breaks the C-like ordering where the variables are
declared or defined before they are used. It is not really needed for
Kconfig. Also the following patches will rework the logic so that
the ordering will be C-like in the end.

The patch just shuffles the definitions. It should not change the existing
behavior.

Link: https://lkml.kernel.org/r/20230616150618.6073-1-pmladek@suse.com
Link: https://lkml.kernel.org/r/20230616150618.6073-2-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

watchdog/buddy: simplify the dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY

The dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY was more complicated
than it needed to be. If the "perf" detector is

watchdog/buddy: simplify the dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY

The dependency for HARDLOCKUP_DETECTOR_PREFER_BUDDY was more complicated
than it needed to be. If the "perf" detector is available and we have SMP
then we have a choice, so enable the config based on just those two config
items.

Link: https://lkml.kernel.org/r/20230526184139.8.I49d5b483336b65b8acb1e5066548a05260caf809@changeid
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Suggested-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...