Merge drm/drm-fixes into drm-misc-fixes

Getting fixes and updates from v7.1-rc1.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Paul Walmsley:
"There is one significant change outside arch/riscv in this

Merge tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Paul Walmsley:
"There is one significant change outside arch/riscv in this pull
request: the addition of a set of KUnit tests for strlen(), strnlen(),
and strrchr().

Otherwise, the most notable changes are to add some RISC-V-specific
string function implementations, to remove XIP kernel support, to add
hardware error exception handling, and to optimize our runtime
unaligned access speed testing.

A few comments on the motivation for removing XIP support. It's been
broken in the RISC-V kernel for months. The code is not easy to
maintain. Furthermore, for XIP support to truly be useful for RISC-V,
we think that compile-time feature switches would need to be added for
many of the RISC-V ISA features and microarchitectural properties that
are currently implemented with runtime patching. No one has stepped
forward to take responsibility for that work, so many of us think it's
best to remove it until clear use cases and champions emerge.

Summary:

- Add Kunit correctness testing and microbenchmarks for strlen(),
strnlen(), and strrchr()

- Add RISC-V-specific strnlen(), strchr(), strrchr() implementations

- Add hardware error exception handling

- Clean up and optimize our unaligned access probe code

- Enable HAVE_IOREMAP_PROT to be able to use generic_access_phys()

- Remove XIP kernel support

- Warn when addresses outside the vmemmap range are passed to
vmemmap_populate()

- Update the ACPI FADT revision check to warn if it's not at least
ACPI v6.6, which is when key RISC-V-specific tables were added to
the specification

- Increase COMMAND_LINE_SIZE to 2048 to match ARM64, x86, PowerPC,
etc.

- Make kaslr_offset() a static inline function, since there's no need
for it to show up in the symbol table

- Add KASLR offset and SATP to the VMCOREINFO ELF notes to improve
kdump support

- Add Makefile cleanup rule for vdso_cfi copied source files, and add
a .gitignore for the build artifacts in that directory

- Remove some redundant ifdefs that check Kconfig macros

- Add missing SPDX license tag to the CFI selftest

- Simplify UTS_MACHINE assignment in the RISC-V Makefile

- Clarify some unclear comments and remove some superfluous comments

- Fix various English typos across the RISC-V codebase"

* tag 'riscv-for-linus-7.1-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits)
riscv: Remove support for XIP kernel
riscv: Reuse compare_unaligned_access() in check_vector_unaligned_access()
riscv: Split out compare_unaligned_access()
riscv: Reuse measure_cycles() in check_vector_unaligned_access()
riscv: Split out measure_cycles() for reuse
riscv: Clean up & optimize unaligned scalar access probe
riscv: lib: add strrchr() implementation
riscv: lib: add strchr() implementation
riscv: lib: add strnlen() implementation
lib/string_kunit: extend benchmarks to strnlen() and chr searches
lib/string_kunit: add performance benchmark for strlen()
lib/string_kunit: add correctness test for strrchr()
lib/string_kunit: add correctness test for strnlen()
lib/string_kunit: add correctness test for strlen()
riscv: vdso_cfi: Add .gitignore for build artifacts
riscv: vdso_cfi: Add clean rule for copied sources
riscv: enable HAVE_IOREMAP_PROT
riscv: mm: WARN_ON() for bad addresses in vmemmap_populate()
riscv: acpi: update FADT revision check to 6.6
riscv: add hardware error trap handler support
...

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Merge drm/drm-fixes into drm-misc-fixes

Tomi needs 7.0 to apply a patch from drm-misc-fixes.

Signed-off-by: Maxime Ripard <mripard@kernel.org>

Merge branch 'for-7.1-printf-kunit-build' into for-linus

Merge branch 'next' into for-linus

Prepare input updates for 7.1 merge window.

Merge branch 'for-7.1/core-v2' into for-linus

- fixed handling of 0-sized reports (Dmitry Torokhov)
- convert core code to __free() (Dmitry Torokhov)
- support for multiple batteries per HID device

Merge branch 'for-7.1/core-v2' into for-linus

- fixed handling of 0-sized reports (Dmitry Torokhov)
- convert core code to __free() (Dmitry Torokhov)
- support for multiple batteries per HID device (Lucas Zampieri)

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Merge tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:

- New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
smalle

Merge tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq

Pull workqueue updates from Tejun Heo:

- New default WQ_AFFN_CACHE_SHARD affinity scope subdivides LLCs into
smaller shards to improve scalability on machines with many CPUs per
LLC

- Misc:
- system_dfl_long_wq for long unbound works
- devm_alloc_workqueue() for device-managed allocation
- sysfs exposure for ordered workqueues and the EFI workqueue
- removal of HK_TYPE_WQ from wq_unbound_cpumask
- various small fixes

* tag 'wq-for-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (21 commits)
workqueue: validate cpumask_first() result in llc_populate_cpu_shard_id()
workqueue: use NR_STD_WORKER_POOLS instead of hardcoded value
workqueue: avoid unguarded 64-bit division
docs: workqueue: document WQ_AFFN_CACHE_SHARD affinity scope
workqueue: add test_workqueue benchmark module
tools/workqueue: add CACHE_SHARD support to wq_dump.py
workqueue: set WQ_AFFN_CACHE_SHARD as the default affinity scope
workqueue: add WQ_AFFN_CACHE_SHARD affinity scope
workqueue: fix typo in WQ_AFFN_SMT comment
workqueue: Remove HK_TYPE_WQ from affecting wq_unbound_cpumask
workqueue: unlink pwqs from wq->pwqs list in alloc_and_link_pwqs() error path
workqueue: Remove NULL wq WARN in __queue_delayed_work()
workqueue: fix parse_affn_scope() prefix matching bug
workqueue: devres: Add device-managed allocate workqueue
workqueue: Add system_dfl_long_wq for long unbound works
tools/workqueue/wq_dump.py: add NODE prefix to all node columns
tools/workqueue/wq_dump.py: fix column alignment in node_nr/max_active section
tools/workqueue/wq_dump.py: remove backslash separator from node_nr/max_active header
efi: Allow to expose the workqueue via sysfs
workqueue: Allow to expose ordered workqueues via sysfs
...

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Merge tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
"Mutexes:

- Add killable flavor to guard definitions (Davidlo

Merge tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
"Mutexes:

- Add killable flavor to guard definitions (Davidlohr Bueso)

- Remove the list_head from struct mutex (Matthew Wilcox)

- Rename mutex_init_lockep() (Davidlohr Bueso)

rwsems:

- Remove the list_head from struct rw_semaphore and
replace it with a single pointer (Matthew Wilcox)

- Fix logic error in rwsem_del_waiter() (Andrei Vagin)

Semaphores:

- Remove the list_head from struct semaphore (Matthew Wilcox)

Jump labels:

- Use ATOMIC_INIT() for initialization of .enabled (Thomas Weißschuh)

- Remove workaround for old compilers in initializations
(Thomas Weißschuh)

Lock context analysis changes and improvements:

- Add context analysis for rwsems (Peter Zijlstra)

- Fix rwlock and spinlock lock context annotations (Bart Van Assche)

- Fix rwlock support in <linux/spinlock_up.h> (Bart Van Assche)

- Add lock context annotations in the spinlock implementation
(Bart Van Assche)

- signal: Fix the lock_task_sighand() annotation (Bart Van Assche)

- ww-mutex: Fix the ww_acquire_ctx function annotations
(Bart Van Assche)

- Add lock context support in do_raw_{read,write}_trylock()
(Bart Van Assche)

- arm64, compiler-context-analysis: Permit alias analysis through
__READ_ONCE() with CONFIG_LTO=y (Marco Elver)

- Add __cond_releases() (Peter Zijlstra)

- Add context analysis for mutexes (Peter Zijlstra)

- Add context analysis for rtmutexes (Peter Zijlstra)

- Convert futexes to compiler context analysis (Peter Zijlstra)

Rust integration updates:

- Add atomic fetch_sub() implementation (Andreas Hindborg)

- Refactor various rust_helper_ methods for expansion (Boqun Feng)

- Add Atomic<*{mut,const} T> support (Boqun Feng)

- Add atomic operation helpers over raw pointers (Boqun Feng)

- Add performance-optimal Flag type for atomic booleans, to avoid
slow byte-sized RMWs on architectures that don't support them.
(FUJITA Tomonori)

- Misc cleanups and fixes (Andreas Hindborg, Boqun Feng, FUJITA
Tomonori)

LTO support updates:

- arm64: Optimize __READ_ONCE() with CONFIG_LTO=y (Marco Elver)

- compiler: Simplify generic RELOC_HIDE() (Marco Elver)

Miscellaneous fixes and cleanups by Peter Zijlstra, Randy Dunlap,
Thomas Weißschuh, Davidlohr Bueso and Mikhail Gavrilov"

* tag 'locking-core-2026-04-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
compiler: Simplify generic RELOC_HIDE()
locking: Add lock context annotations in the spinlock implementation
locking: Add lock context support in do_raw_{read,write}_trylock()
locking: Fix rwlock support in <linux/spinlock_up.h>
lockdep: Raise default stack trace limits when KASAN is enabled
cleanup: Optimize guards
jump_label: remove workaround for old compilers in initializations
jump_label: use ATOMIC_INIT() for initialization of .enabled
futex: Convert to compiler context analysis
locking/rwsem: Fix logic error in rwsem_del_waiter()
locking/rwsem: Add context analysis
locking/rtmutex: Add context analysis
locking/mutex: Add context analysis
compiler-context-analysys: Add __cond_releases()
locking/mutex: Remove the list_head from struct mutex
locking/semaphore: Remove the list_head from struct semaphore
locking/rwsem: Remove the list_head from struct rw_semaphore
rust: atomic: Update a safety comment in impl of `fetch_add()`
rust: sync: atomic: Update documentation for `fetch_add()`
rust: sync: atomic: Add fetch_sub()
...

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Merge tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

Pull crypto library updates from Eric Biggers:

- Migrate more hash algorithms from the traditional c

Merge tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

Pull crypto library updates from Eric Biggers:

- Migrate more hash algorithms from the traditional crypto subsystem to
lib/crypto/

Like the algorithms migrated earlier (e.g. SHA-*), this simplifies
the implementations, improves performance, enables further
simplifications in calling code, and solves various other issues:

- AES CBC-based MACs (AES-CMAC, AES-XCBC-MAC, and AES-CBC-MAC)

- Support these algorithms in lib/crypto/ using the AES library
and the existing arm64 assembly code

- Reimplement the traditional crypto API's "cmac(aes)",
"xcbc(aes)", and "cbcmac(aes)" on top of the library

- Convert mac80211 to use the AES-CMAC library. Note: several
other subsystems can use it too and will be converted later

- Drop the broken, nonstandard, and likely unused support for
"xcbc(aes)" with key lengths other than 128 bits

- Enable optimizations by default

- GHASH

- Migrate the standalone GHASH code into lib/crypto/

- Integrate the GHASH code more closely with the very similar
POLYVAL code, and improve the generic GHASH implementation to
resist cache-timing attacks and use much less memory

- Reimplement the AES-GCM library and the "gcm" crypto_aead
template on top of the GHASH library. Remove "ghash" from the
crypto_shash API, as it's no longer needed

- Enable optimizations by default

- SM3

- Migrate the kernel's existing SM3 code into lib/crypto/, and
reimplement the traditional crypto API's "sm3" on top of it

- I don't recommend using SM3, but this cleanup is worthwhile
to organize the code the same way as other algorithms

- Testing improvements:

- Add a KUnit test suite for each of the new library APIs

- Migrate the existing ChaCha20Poly1305 test to KUnit

- Make the KUnit all_tests.config enable all crypto library tests

- Move the test kconfig options to the Runtime Testing menu

- Other updates to arch-optimized crypto code:

- Optimize SHA-256 for Zhaoxin CPUs using the Padlock Hash Engine

- Remove some MD5 implementations that are no longer worth keeping

- Drop big endian and voluntary preemption support from the arm64
code, as those configurations are no longer supported on arm64

- Make jitterentropy and samples/tsm-mr use the crypto library APIs

* tag 'libcrypto-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: (66 commits)
lib/crypto: arm64: Assume a little-endian kernel
arm64: fpsimd: Remove obsolete cond_yield macro
lib/crypto: arm64/sha3: Remove obsolete chunking logic
lib/crypto: arm64/sha512: Remove obsolete chunking logic
lib/crypto: arm64/sha256: Remove obsolete chunking logic
lib/crypto: arm64/sha1: Remove obsolete chunking logic
lib/crypto: arm64/poly1305: Remove obsolete chunking logic
lib/crypto: arm64/gf128hash: Remove obsolete chunking logic
lib/crypto: arm64/chacha: Remove obsolete chunking logic
lib/crypto: arm64/aes: Remove obsolete chunking logic
lib/crypto: Include <crypto/utils.h> instead of <crypto/algapi.h>
lib/crypto: aesgcm: Don't disable IRQs during AES block encryption
lib/crypto: aescfb: Don't disable IRQs during AES block encryption
lib/crypto: tests: Migrate ChaCha20Poly1305 self-test to KUnit
lib/crypto: sparc: Drop optimized MD5 code
lib/crypto: mips: Drop optimized MD5 code
lib: Move crypto library tests to Runtime Testing menu
crypto: sm3 - Remove 'struct sm3_state'
crypto: sm3 - Remove the original "sm3_block_generic()"
crypto: sm3 - Remove sm3_base.h
...

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Merge tag 'rust-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

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

- Bump the minimum Rust version to 1.85.0 (

Merge tag 'rust-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux

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

- Bump the minimum Rust version to 1.85.0 (and 'bindgen' to 0.71.1).

As proposed in LPC 2025 and the Maintainers Summit [1], we are
going to follow Debian Stable's Rust versions as our minimum
versions.

Debian Trixie was released on 2025-08-09 with a Rust 1.85.0 and
'bindgen' 0.71.1 toolchain, which is a fair amount of time for e.g.
kernel developers to upgrade.

Other major distributions support a Rust version that is high
enough as well, including:

+ Arch Linux.
+ Fedora Linux.
+ Gentoo Linux.
+ Nix.
+ openSUSE Slowroll and openSUSE Tumbleweed.
+ Ubuntu 25.10 and 26.04 LTS. In addition, 24.04 LTS using
their versioned packages.

The merged patch series comes with the associated cleanups and
simplifications treewide that can be performed thanks to both
bumps, as well as documentation updates.

In addition, start using 'bindgen''s '--with-attribute-custom-enum'
feature to set the 'cfi_encoding' attribute for the 'lru_status'
enum used in Binder.

Link: https://lwn.net/Articles/1050174/ [1]

- Add experimental Kconfig option ('CONFIG_RUST_INLINE_HELPERS') that
inlines C helpers into Rust.

Essentially, it performs a step similar to LTO, but just for the
helpers, i.e. very local and fast.

It relies on 'llvm-link' and its '--internalize' flag, and requires
a compatible LLVM between Clang and 'rustc' (i.e. same major
version, 'CONFIG_RUSTC_CLANG_LLVM_COMPATIBLE'). It is only enabled
for two architectures for now.

The result is a measurable speedup in different workloads that
different users have tested. For instance, for the null block
driver, it amounts to a 2%.

- Support global per-version flags.

While we already have per-version flags in many places, we didn't
have a place to set global ones that depend on the compiler
version, i.e. in 'rust_common_flags', which sometimes is needed to
e.g. tweak the lints set per version.

Use that to allow the 'clippy::precedence' lint for Rust < 1.86.0,
since it had a change in behavior.

- Support overriding the crate name and apply it to Rust Binder,
which wanted the module to be called 'rust_binder'.

- Add the remaining '__rust_helper' annotations (started in the
previous cycle).

'kernel' crate:

- Introduce the 'const_assert!' macro: a more powerful version of
'static_assert!' that can refer to generics inside functions or
implementation bodies, e.g.:

fn f<const N: usize>() {
const_assert!(N > 1);
}

fn g<T>() {
const_assert!(size_of::<T>() > 0, "T cannot be ZST");
}

In addition, reorganize our set of build-time assertion macros
('{build,const,static_assert}!') to live in the 'build_assert'
module.

Finally, improve the docs as well to clarify how these are
different from one another and how to pick the right one to use,
and their equivalence (if any) to the existing C ones for extra
clarity.

- 'sizes' module: add 'SizeConstants' trait.

This gives us typed 'SZ_*' constants (avoiding casts) for use in
device address spaces where the address width depends on the
hardware (e.g. 32-bit MMIO windows, 64-bit GPU framebuffers, etc.),
e.g.:

let gpu_heap = 14 * u64::SZ_1M;
let mmio_window = u32::SZ_16M;

- 'clk' module: implement 'Send' and 'Sync' for 'Clk' and thus
simplify the users in Tyr and PWM.

- 'ptr' module: add 'const_align_up'.

- 'str' module: improve the documentation of the 'c_str!' macro to
explain that one should only use it for non-literal cases (for the
other case we instead use C string literals, e.g. 'c"abc"').

- Disallow the use of 'CStr::{as_ptr,from_ptr}' and clean one such
use in the 'task' module.

- 'sync' module: finish the move of 'ARef' and 'AlwaysRefCounted'
outside of the 'types' module, i.e. update the last remaining
instances and finally remove the re-exports.

- 'error' module: clarify that 'from_err_ptr' can return 'Ok(NULL)',
including runtime-tested examples.

The intention is to hopefully prevent UB that assumes the result of
the function is not 'NULL' if successful. This originated from a
case of UB I noticed in 'regulator' that created a 'NonNull' on it.

Timekeeping:

- Expand the example section in the 'HrTimer' documentation.

- Mark the 'ClockSource' trait as unsafe to ensure valid values for
'ktime_get()'.

- Add 'Delta::from_nanos()'.

'pin-init' crate:

- Replace the 'Zeroable' impls for 'Option<NonZero*>' with impls of
'ZeroableOption' for 'NonZero*'.

- Improve feature gate handling for unstable features.

- Declutter the documentation of implementations of 'Zeroable' for
tuples.

- Replace uses of 'addr_of[_mut]!' with '&raw [mut]'.

rust-analyzer:

- Add type annotations to 'generate_rust_analyzer.py'.

- Add support for scripts written in Rust ('generate_rust_target.rs',
'rustdoc_test_builder.rs', 'rustdoc_test_gen.rs').

- Refactor 'generate_rust_analyzer.py' to explicitly identify host
and target crates, improve readability, and reduce duplication.

And some other fixes, cleanups and improvements"

* tag 'rust-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (79 commits)
rust: sizes: add SizeConstants trait for device address space constants
rust: kernel: update `file_with_nul` comment
rust: kbuild: allow `clippy::precedence` for Rust < 1.86.0
rust: kbuild: support global per-version flags
rust: declare cfi_encoding for lru_status
docs: rust: general-information: use real example
docs: rust: general-information: simplify Kconfig example
docs: rust: quick-start: remove GDB/Binutils mention
docs: rust: quick-start: remove Nix "unstable channel" note
docs: rust: quick-start: remove Gentoo "testing" note
docs: rust: quick-start: add Ubuntu 26.04 LTS and remove subsection title
docs: rust: quick-start: update minimum Ubuntu version
docs: rust: quick-start: update Ubuntu versioned packages
docs: rust: quick-start: openSUSE provides `rust-src` package nowadays
rust: kbuild: remove "dummy parameter" workaround for `bindgen` < 0.71.1
rust: kbuild: update `bindgen --rust-target` version and replace comment
rust: rust_is_available: remove warning for `bindgen` < 0.69.5 && libclang >= 19.1
rust: rust_is_available: remove warning for `bindgen` 0.66.[01]
rust: bump `bindgen` minimum supported version to 0.71.1 (Debian Trixie)
rust: block: update `const_refs_to_static` MSRV TODO comment
...

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lib/string_kunit: add performance benchmark for strlen()

Introduce a benchmarking framework to the string_kunit test suite to
measure the execution efficiency of string functions.

The implementatio

lib/string_kunit: add performance benchmark for strlen()

Introduce a benchmarking framework to the string_kunit test suite to
measure the execution efficiency of string functions.

The implementation is inspired by crc_benchmark(), measuring throughput
(MB/s) and latency (ns/call) across a range of string lengths. It
includes a warm-up phase, disables preemption during measurement, and
uses a fixed seed for reproducible results.

This framework allows for comparing different implementations (e.g.,
generic C vs. architecture-optimized assembly) within the KUnit
environment.

Initially, provide a benchmark for strlen().

Suggested-by: Andy Shevchenko <andy@kernel.org>
Suggested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Feng Jiang <jiangfeng@kylinos.cn>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20260130025018.172925-5-jiangfeng@kylinos.cn
[pjw@kernel.org: fixed a checkpatch issue]
Signed-off-by: Paul Walmsley <pjw@kernel.org>

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workqueue: add test_workqueue benchmark module

Add a kernel module that benchmarks queue_work() throughput on an
unbound workqueue to measure pool->lock contention under different
affinity scope con

workqueue: add test_workqueue benchmark module

Add a kernel module that benchmarks queue_work() throughput on an
unbound workqueue to measure pool->lock contention under different
affinity scope configurations (cache vs cache_shard).

The module spawns N kthreads (default: num_online_cpus()), each bound
to a different CPU. All threads start simultaneously and queue work
items, measuring the latency of each queue_work() call. Results are
reported as p50/p90/p95 latencies for each affinity scope.

The affinity scope is switched between runs via the workqueue's sysfs
affinity_scope attribute (WQ_SYSFS), avoiding the need for any new
exported symbols.

The module runs as __init-only, returning -EAGAIN to auto-unload,
and can be re-run via insmod.

Example of the output:

running 50 threads, 50000 items/thread

cpu 6806017 items/sec p50=2574 p90=5068 p95=5818 ns
smt 6821040 items/sec p50=2624 p90=5168 p95=5949 ns
cache_shard 1633653 items/sec p50=5337 p90=9694 p95=11207 ns
cache 286069 items/sec p50=72509 p90=82304 p95=85009 ns
numa 319403 items/sec p50=63745 p90=73480 p95=76505 ns
system 308461 items/sec p50=66561 p90=75714 p95=78048 ns

Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

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Merge branch 'for-linus' into for-next

Pull 7.0 devel branch for further cleanups of ctxfi driver & co.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

kbuild: rust: provide an option to inline C helpers into Rust

A new experimental Kconfig option, `RUST_INLINE_HELPERS` is added to
allow C helpers (which were created to allow Rust to call into
inli

kbuild: rust: provide an option to inline C helpers into Rust

A new experimental Kconfig option, `RUST_INLINE_HELPERS` is added to
allow C helpers (which were created to allow Rust to call into
inline/macro C functions without having to re-implement the logic in
Rust) to be inlined into Rust crates without performing global LTO.

If the option is enabled, the following is performed:
* For helpers, instead of compiling them to an object file to be linked
into vmlinux, they're compiled to LLVM IR bitcode. Two versions are
generated: one for built-in code (`helpers.bc`) and one for modules
(`helpers_module.bc`, with -DMODULE defined). This ensures that C
macros/inlines that behave differently for modules (e.g. static calls)
function correctly when inlined.
* When a Rust crate or object is compiled, instead of generating an
object file, LLVM bitcode is generated.
* llvm-link is invoked with --internalize to combine the helper bitcode
with the crate bitcode. This step is similar to LTO, but this is much
faster since it only needs to inline the helpers.
* clang is invoked to turn the combined bitcode into a final object file.
* Since clang may produce LLVM bitcode when LTO is enabled, and objtool
requires ELF input, $(cmd_ld_single) is invoked to ensure the object
is converted to ELF before objtool runs.

The --internalize flag tells llvm-link to treat all symbols in
helpers.bc using `internal` linkage [1]. This matches the behavior of
`clang` on `static inline` functions, and avoids exporting the symbol
from the object file.

To ensure that RUST_INLINE_HELPERS is not incompatible with BTF, we pass
the -g0 flag when building helpers. See commit 5daa0c35a1f0 ("rust:
Disallow BTF generation with Rust + LTO") for details.

We have an intended triple mismatch of `aarch64-unknown-none` vs
`aarch64-unknown-linux-gnu`, so we pass --suppress-warnings to llvm-link
to suppress it.

I considered adding some sort of check that KBUILD_MODNAME is not
present in helpers_module.bc, but this is actually not so easy to carry
out because .bc files store strings in a weird binary format, so you
cannot just grep it for a string to check whether it ended up using
KBUILD_MODNAME anywhere.

[ Andreas writes:

For the rnull driver, enabling helper inlining with this patch
gives an average speedup of 2% over the set of 120 workloads that
we publish on [2].

Link: https://rust-for-linux.com/null-block-driver [2]

This series also uncovered a pre-existing UB instance thanks to an
`objtool` warning which I noticed while testing the series (details
in the mailing list).

- Miguel ]

Link: https://github.com/llvm/llvm-project/pull/170397 [1]
Co-developed-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Co-developed-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Gary Guo <gary@garyguo.net>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Link: https://patch.msgid.link/20260203-inline-helpers-v2-3-beb8547a03c9@google.com
[ Some changes, apart from the rebase:

- Added "(EXPERIMENTAL)" to Kconfig as the commit mentions.

- Added `depends on ARM64 || X86_64` and `!UML` for now, since this is
experimental, other architectures may require other changes (e.g.
the issues I mentioned in the mailing list for ARM and UML) and they
are not really tested so far. So let arch maintainers pick this up
if they think it is worth it.

- Gated the `cmd_ld_single` step also into the new mode, which also
means that any possible future `objcopy` step is done after the
translation, as expected.

- Added `.gitignore` for `.bc` with exception for existing script.

- Added `part-of-*` for helpers bitcode files as discussed, and
dropped `$(if $(filter %_module.bc,$@),-DMODULE)` since `-DMODULE`
is already there (would be duplicated otherwise).

- Moved `LLVM_LINK` to keep binutils list alphabetized.

- Fixed typo in title.

- Dropped second `cmd_ld_single` commit message paragraph.

- Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

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Merge tag 'perf-tools-fixes-for-v7.0-2-2026-03-23' into perf-tools-next

To get the various fixes for v7.0.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>

lib: Move crypto library tests to Runtime Testing menu

Currently the kconfig options for the crypto library KUnit tests appear
in the menu:

-> Library routines
-> Crypto library routines

lib: Move crypto library tests to Runtime Testing menu

Currently the kconfig options for the crypto library KUnit tests appear
in the menu:

-> Library routines
-> Crypto library routines

However, this is the only content of "Crypto library routines". I.e.,
it is empty when CONFIG_KUNIT=n. This is because the crypto library
routines themselves don't have (or need to have) prompts.

Since this usually ends up as an unnecessary empty menu, let's remove
this menu and instead source the lib/crypto/tests/Kconfig file from
lib/Kconfig.debug inside the "Runtime Testing" menu:

-> Kernel hacking
-> Kernel Testing and Coverage
-> Runtime Testing

This puts the prompts alongside the ones for most of the other lib/
KUnit tests. This seems to be a much better match to how the kconfig
menus are organized.

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20260322032438.286296-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

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Merge tag 'v7.0-rc4' into togreg

Linux 7.0-rc4

Required for the ds4422 series which is build upon;
5187e03b817c ("iio: dac: ds4424: reject -128 RAW value")

Merge tag 'v7.0-rc4' into timers/core, to resolve conflict

Resolve conflict between this change in the upstream kernel:

4c652a47722f ("rseq: Mark rseq_arm_slice_extension_timer() __always_inline"

Merge tag 'v7.0-rc4' into timers/core, to resolve conflict

Resolve conflict between this change in the upstream kernel:

4c652a47722f ("rseq: Mark rseq_arm_slice_extension_timer() __always_inline")

... and this pending change in timers/core:

0e98eb14814e ("entry: Prepare for deferred hrtimer rearming")

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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lockdep: Raise default stack trace limits when KASAN is enabled

KASAN-enabled kernels with LOCKDEP and PREEMPT_FULL hit
"BUG: MAX_STACK_TRACE_ENTRIES too low!" within 9-23 hours of normal
desktop us

lockdep: Raise default stack trace limits when KASAN is enabled

KASAN-enabled kernels with LOCKDEP and PREEMPT_FULL hit
"BUG: MAX_STACK_TRACE_ENTRIES too low!" within 9-23 hours of normal
desktop use.

The root cause is a feedback loop between KASAN slab tracking and
lockdep: every KASAN-tracked slab allocation saves a stack trace via
stack_trace_save() -> arch_stack_walk(). The unwinder calls
is_bpf_text_address(), which under PREEMPT_FULL can trigger RCU
deferred quiescent-state processing -> swake_up_one() -> lock_acquire()
-> lockdep validate_chain() -> save_trace(). This means KASAN's own
stack captures indirectly generate new lockdep dependency chains,
consuming the buffer from both directions.

/proc/lockdep_stats at the moment of overflow confirms that
stack-trace entries is the sole exhausted resource:

stack-trace entries: 524288 [max: 524288] <- 100% full
number of stack traces: 22080 <- unique after dedup
dependency chains: 164665 [max: 524288] <- only 31% used
direct dependencies: 45270 [max: 65536] <- 69%
lock-classes: 2811 [max: 8192] <- 34%

22080 genuinely unique traces averaging ~24 frames each fill the
buffer in under a day. The hash-based deduplication (12593b7467f9) is
working correctly -- the traces are simply all different due to the
deep and varied call stacks from GPU + filesystem + Wine/Proton + KASAN
instrumentation.

Raise the LOCKDEP_STACK_TRACE_BITS default from 19 to 21 when KASAN is
enabled (2M entries, +12MB). This is negligible compared to KASAN's
own shadow memory overhead (~12.5% of total RAM). Scale
LOCKDEP_STACK_TRACE_HASH_BITS accordingly to maintain dedup efficiency.

Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260313171118.1702954-2-mikhail.v.gavrilov@gmail.com

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Merge 7.0-rc4 into usb-next

We need the USB fixes in this branch as well to build on top of

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge 7.0-rc4 into staging-next

We need the staging driver fixes in here to build on top of

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge 7.0-rc4 into char-misc-next

We need the char/misc/iio fixes in this branch as well to build on top
of.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Merge tag 'v7.0-rc4' into drm-rust-next

We need the latest fixes from drm-rust-fixes in drm-rust-next as well to
build on top of.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>

Merge tag 'v7.0-rc3' into next

Sync up with the mainline to brig up the latest changes, specifically
changes to ALPS driver.

Merge drm/drm-next into drm-xe-next

Backmerging to bring in 7.00-rc3. Important ahead GPU SVM merging THP
support.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>