[ Upstream commit fad472efab ]
The `rustdoc` modifiers bug [1] was fixed in Rust 1.90.0 [2], for which
we added a workaround in commit abbf9a4494 ("rust: workaround `rustdoc`
target modifiers bug").
However, `rustdoc`'s doctest generation still has a similar issue [3],
being fixed at [4], which does not affect us because we apply the
workaround to both, and now, starting with Rust 1.91.0 (released
2025-10-30), `-Zsanitizer` is a target modifier too [5], which means we
fail with:
RUSTDOC TK rust/kernel/lib.rs
error: mixing `-Zsanitizer` will cause an ABI mismatch in crate `kernel`
--> rust/kernel/lib.rs:3:1
|
3 | //! The `kernel` crate.
| ^
|
= help: the `-Zsanitizer` flag modifies the ABI so Rust crates compiled with different values of this flag cannot be used together safely
= note: unset `-Zsanitizer` in this crate is incompatible with `-Zsanitizer=kernel-address` in dependency `core`
= help: set `-Zsanitizer=kernel-address` in this crate or unset `-Zsanitizer` in `core`
= help: if you are sure this will not cause problems, you may use `-Cunsafe-allow-abi-mismatch=sanitizer` to silence this error
A simple way around is to add the sanitizer to the list in the existing
workaround (especially if we had not started to pass the sanitizer
flags in the previous commit, since in that case that would not be
necessary). However, that still applies the workaround in more cases
than necessary.
Instead, only modify the doctests flags to ignore the check for
sanitizers, so that it is more local (and thus the compiler keeps checking
it for us in the normal `rustdoc` calls). Since the previous commit
already treated the `rustdoc` calls as kernel objects, this should allow
us in the future to easily remove this workaround when the time comes.
By the way, the `-Cunsafe-allow-abi-mismatch` flag overwrites previous
ones rather than appending, so it needs to be all done in the same flag.
Moreover, unknown modifiers are rejected, and thus we have to gate based
on the version too.
Finally, `-Zsanitizer-cfi-normalize-integers` is not affected (in Rust
1.91.0), so it is not needed in the workaround for the moment.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/issues/144521 [1]
Link: https://github.com/rust-lang/rust/pull/144523 [2]
Link: https://github.com/rust-lang/rust/issues/146465 [3]
Link: https://github.com/rust-lang/rust/pull/148068 [4]
Link: https://github.com/rust-lang/rust/pull/138736 [5]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Justin M. Forbes <jforbes@fedoraproject.org>
Link: https://patch.msgid.link/20251102212853.1505384-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
[ added --remap-path-prefix comments missing in stable branch ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 16c43a56b7 ]
Even if normally `build_error` isn't a kernel object, it should still
be treated as such so that we pass the same flags. Similarly, `rustdoc`
targets are never kernel objects, but we need to treat them as such.
Otherwise, starting with Rust 1.91.0 (released 2025-10-30), `rustc`
will complain about missing sanitizer flags since `-Zsanitizer` is a
target modifier too [1]:
error: mixing `-Zsanitizer` will cause an ABI mismatch in crate `build_error`
--> rust/build_error.rs:3:1
|
3 | //! Build-time error.
| ^
|
= help: the `-Zsanitizer` flag modifies the ABI so Rust crates compiled with different values of this flag cannot be used together safely
= note: unset `-Zsanitizer` in this crate is incompatible with `-Zsanitizer=kernel-address` in dependency `core`
= help: set `-Zsanitizer=kernel-address` in this crate or unset `-Zsanitizer` in `core`
= help: if you are sure this will not cause problems, you may use `-Cunsafe-allow-abi-mismatch=sanitizer` to silence this error
Thus explicitly mark them as kernel objects.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/138736 [1]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Justin M. Forbes <jforbes@fedoraproject.org>
Link: https://patch.msgid.link/20251102212853.1505384-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
[ Adjust context ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fe4b3a34e9 ]
It's used to work around an objtool issue since commit abb2a55722
("LoongArch: Add cflag -fno-isolate-erroneous-paths-dereference"), but
it's then passed to bindgen and cause an error because Clang does not
have this option.
Fixes: abb2a55722 ("LoongArch: Add cflag -fno-isolate-erroneous-paths-dereference")
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Tested-by: Mingcong Bai <jeffbai@aosc.io>
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f04aad36a0 upstream.
syzkaller discovered the following crash: (kernel BUG)
[ 44.607039] ------------[ cut here ]------------
[ 44.607422] kernel BUG at mm/userfaultfd.c:2067!
[ 44.608148] Oops: invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN NOPTI
[ 44.608814] CPU: 1 UID: 0 PID: 2475 Comm: reproducer Not tainted 6.16.0-rc6 #1 PREEMPT(none)
[ 44.609635] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
[ 44.610695] RIP: 0010:userfaultfd_release_all+0x3a8/0x460
<snip other registers, drop unreliable trace>
[ 44.617726] Call Trace:
[ 44.617926] <TASK>
[ 44.619284] userfaultfd_release+0xef/0x1b0
[ 44.620976] __fput+0x3f9/0xb60
[ 44.621240] fput_close_sync+0x110/0x210
[ 44.622222] __x64_sys_close+0x8f/0x120
[ 44.622530] do_syscall_64+0x5b/0x2f0
[ 44.622840] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 44.623244] RIP: 0033:0x7f365bb3f227
Kernel panics because it detects UFFD inconsistency during
userfaultfd_release_all(). Specifically, a VMA which has a valid pointer
to vma->vm_userfaultfd_ctx, but no UFFD flags in vma->vm_flags.
The inconsistency is caused in ksm_madvise(): when user calls madvise()
with MADV_UNMEARGEABLE on a VMA that is registered for UFFD in MINOR mode,
it accidentally clears all flags stored in the upper 32 bits of
vma->vm_flags.
Assuming x86_64 kernel build, unsigned long is 64-bit and unsigned int and
int are 32-bit wide. This setup causes the following mishap during the &=
~VM_MERGEABLE assignment.
VM_MERGEABLE is a 32-bit constant of type unsigned int, 0x8000'0000.
After ~ is applied, it becomes 0x7fff'ffff unsigned int, which is then
promoted to unsigned long before the & operation. This promotion fills
upper 32 bits with leading 0s, as we're doing unsigned conversion (and
even for a signed conversion, this wouldn't help as the leading bit is 0).
& operation thus ends up AND-ing vm_flags with 0x0000'0000'7fff'ffff
instead of intended 0xffff'ffff'7fff'ffff and hence accidentally clears
the upper 32-bits of its value.
Fix it by changing `VM_MERGEABLE` constant to unsigned long, using the
BIT() macro.
Note: other VM_* flags are not affected: This only happens to the
VM_MERGEABLE flag, as the other VM_* flags are all constants of type int
and after ~ operation, they end up with leading 1 and are thus converted
to unsigned long with leading 1s.
Note 2:
After commit 31defc3b01 ("userfaultfd: remove (VM_)BUG_ON()s"), this is
no longer a kernel BUG, but a WARNING at the same place:
[ 45.595973] WARNING: CPU: 1 PID: 2474 at mm/userfaultfd.c:2067
but the root-cause (flag-drop) remains the same.
[akpm@linux-foundation.org: rust bindgen wasn't able to handle BIT(), from Miguel]
Link: https://lore.kernel.org/oe-kbuild-all/202510030449.VfSaAjvd-lkp@intel.com/
Link: https://lkml.kernel.org/r/20251001090353.57523-2-acsjakub@amazon.de
Fixes: 7677f7fd8b ("userfaultfd: add minor fault registration mode")
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: SeongJae Park <sj@kernel.org>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Xu Xin <xu.xin16@zte.com.cn>
Cc: Chengming Zhou <chengming.zhou@linux.dev>
Cc: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[acsjakub@amazon.de: adjust context in bindgings_helper.h]
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 208d7f788e upstream.
This `srctree/` link pointed to a file with an underscore, but the header
used a dash instead.
Thus fix it.
This cleans a future warning that will check our `srctree/` links.
Cc: stable@vger.kernel.org
Fixes: 3253aba340 ("rust: block: introduce `kernel::block::mq` module")
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0f580d5d3d ]
Commit fde578c862 ("rust: alloc: replace aligned_size() with
Kmalloc::aligned_layout()") provides a public `aligned_layout` function
in `Kamlloc`, but not in `Cmalloc`, and thus uses of it will trigger an
error in `rusttest`.
Such a user appeared in the following commit 22ab0641b9 ("rust: drm:
ensure kmalloc() compatible Layout"):
error[E0599]: no function or associated item named `aligned_layout` found for struct `alloc::allocator_test::Cmalloc` in the current scope
--> rust/kernel/drm/device.rs:100:31
|
100 | let layout = Kmalloc::aligned_layout(Layout::new::<Self>());
| ^^^^^^^^^^^^^^ function or associated item not found in `Cmalloc`
|
::: rust/kernel/alloc/allocator_test.rs:19:1
|
19 | pub struct Cmalloc;
| ------------------ function or associated item `aligned_layout` not found for this struct
Thus add an equivalent one for `Cmalloc`.
Fixes: fde578c862 ("rust: alloc: replace aligned_size() with Kmalloc::aligned_layout()")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250816204215.2719559-1-ojeda@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit fde578c862 ]
aligned_size() dates back to when Rust did support kmalloc() only, but
is now used in ReallocFunc::call() and hence for all allocators.
However, the additional padding applied by aligned_size() is only
required by the kmalloc() allocator backend.
Hence, replace aligned_size() with Kmalloc::aligned_layout() and use it
for the affected allocators, i.e. kmalloc() and kvmalloc(), only.
While at it, make Kmalloc::aligned_layout() public, such that Rust
abstractions, which have to call subsystem specific kmalloc() based
allocation primitives directly, can make use of it.
Fixes: 8a799831fc ("rust: alloc: implement `ReallocFunc`")
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250731154919.4132-2-dakr@kernel.org
[ Remove `const` from Kmalloc::aligned_layout(). - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit abbf9a4494 upstream.
Starting with Rust 1.88.0 (released 2025-06-26), `rustdoc` complains
about a target modifier mismatch in configurations where `-Zfixed-x18`
is passed:
error: mixing `-Zfixed-x18` will cause an ABI mismatch in crate `rust_out`
|
= help: the `-Zfixed-x18` flag modifies the ABI so Rust crates compiled with different values of this flag cannot be used together safely
= note: unset `-Zfixed-x18` in this crate is incompatible with `-Zfixed-x18=` in dependency `core`
= help: set `-Zfixed-x18=` in this crate or unset `-Zfixed-x18` in `core`
= help: if you are sure this will not cause problems, you may use `-Cunsafe-allow-abi-mismatch=fixed-x18` to silence this error
The reason is that `rustdoc` was not passing the target modifiers when
configuring the session options, and thus it would report a mismatch
that did not exist as soon as a target modifier is used in a dependency.
We did not notice it in the kernel until now because `-Zfixed-x18` has
been a target modifier only since 1.88.0 (and it is the only one we use
so far).
The issue has been reported upstream [1] and a fix has been submitted
[2], including a test similar to the kernel case.
[ This is now fixed upstream (thanks Guillaume for the quick review),
so it will be fixed in Rust 1.90.0 (expected 2025-09-18).
- Miguel ]
Meanwhile, conditionally pass `-Cunsafe-allow-abi-mismatch=fixed-x18`
to workaround the issue on our side.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Reported-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Closes: https://lore.kernel.org/rust-for-linux/36cdc798-524f-4910-8b77-d7b9fac08d77@oss.qualcomm.com/
Link: https://github.com/rust-lang/rust/issues/144521 [1]
Link: https://github.com/rust-lang/rust/pull/144523 [2]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250727092317.2930617-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 252fea131e upstream.
`rustdoc` can get confused when generating documentation into a folder
that contains generated files from other `rustdoc` versions.
For instance, running something like:
rustup default 1.78.0
make LLVM=1 rustdoc
rustup default 1.88.0
make LLVM=1 rustdoc
may generate errors like:
error: couldn't generate documentation: invalid template: last line expected to start with a comment
|
= note: failed to create or modify "./Documentation/output/rust/rustdoc/src-files.js"
Thus just always clean the output folder before generating the
documentation -- we are anyway regenerating it every time the `rustdoc`
target gets called, at least for the time being.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Reported-by: Daniel Almeida <daniel.almeida@collabora.com>
Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/288089/topic/x/near/527201113
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Link: https://lore.kernel.org/r/20250726133435.2460085-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7498159226 upstream.
Starting with Rust 1.89.0 (expected 2025-08-07), the Rust compiler fails
to build the `rusttest` target due to undefined references such as:
kernel...-cgu.0:(.text....+0x116): undefined reference to
`rust_helper_kunit_get_current_test'
Moreover, tooling like `modpost` gets confused:
WARNING: modpost: missing MODULE_DESCRIPTION() in drivers/gpu/drm/nova/nova.o
ERROR: modpost: missing MODULE_LICENSE() in drivers/gpu/nova-core/nova_core.o
The reason behind both issues is that the Rust compiler will now [1]
treat `#[used]` as `#[used(linker)]` instead of `#[used(compiler)]`
for our targets. This means that the retain section flag (`R`,
`SHF_GNU_RETAIN`) will be used and that they will be marked as `unique`
too, with different IDs. In turn, that means we end up with undefined
references that did not get discarded in `rusttest` and that multiple
`.modinfo` sections are generated, which confuse tooling like `modpost`
because they only expect one.
Thus start using `#[used(compiler)]` to keep the previous behavior
and to be explicit about what we want. Sadly, it is an unstable feature
(`used_with_arg`) [2] -- we will talk to upstream Rust about it. The good
news is that it has been available for a long time (Rust >= 1.60) [3].
The changes should also be fine for previous Rust versions, since they
behave the same way as before [4].
Alternatively, we could use `#[no_mangle]` or `#[export_name = ...]`
since those still behave like `#[used(compiler)]`, but of course it is
not really what we want to express, and it requires other changes to
avoid symbol conflicts.
Cc: David Wood <david@davidtw.co>
Cc: Wesley Wiser <wwiser@gmail.com>
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/140872 [1]
Link: https://github.com/rust-lang/rust/issues/93798 [2]
Link: https://github.com/rust-lang/rust/pull/91504 [3]
Link: https://godbolt.org/z/sxzWTMfzW [4]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Björn Roy Baron <bjorn3_gh@protonmail.com>
Link: https://lore.kernel.org/r/20250712160103.1244945-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting with Rust 1.89.0 (expected 2025-08-07), the Rust compiler
may warn:
error: trait `MustNotImplDrop` is never used
--> rust/kernel/init/macros.rs:927:15
|
927 | trait MustNotImplDrop {}
| ^^^^^^^^^^^^^^^
|
::: rust/kernel/sync/arc.rs:133:1
|
133 | #[pin_data]
| ----------- in this procedural macro expansion
|
= note: `-D dead-code` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(dead_code)]`
= note: this error originates in the macro `$crate::__pin_data`
which comes from the expansion of the attribute macro
`pin_data` (in Nightly builds, run with
-Z macro-backtrace for more info)
Thus `allow` it to clean it up.
This does not happen in mainline nor 6.15.y, because there the macro was
moved out of the `kernel` crate, and `dead_code` warnings are not
emitted if the macro is foreign to the crate. Thus this patch is
directly sent to stable and intended for 6.12.y only.
Similarly, it is not needed in previous LTSs, because there the Rust
version is pinned.
Acked-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 977c4308ee ]
Currently rust on arm fails to compile due to '-mno-fdpic'. This flag
disables a GCC feature that we don't want for kernel builds, so let's
skip it as it doesn't apply to Clang.
UPD include/generated/asm-offsets.h
CALL scripts/checksyscalls.sh
RUSTC L rust/core.o
BINDGEN rust/bindings/bindings_generated.rs
BINDGEN rust/bindings/bindings_helpers_generated.rs
CC rust/helpers/helpers.o
Unable to generate bindings: clang diagnosed error: error: unknown argument: '-mno-fdpic'
make[2]: *** [rust/Makefile:369: rust/bindings/bindings_helpers_generated.rs] Error 1
make[2]: *** Deleting file 'rust/bindings/bindings_helpers_generated.rs'
make[2]: *** Waiting for unfinished jobs....
Unable to generate bindings: clang diagnosed error: error: unknown argument: '-mno-fdpic'
make[2]: *** [rust/Makefile:349: rust/bindings/bindings_generated.rs] Error 1
make[2]: *** Deleting file 'rust/bindings/bindings_generated.rs'
make[1]: *** [/home/pmos/build/src/linux-next-next-20250521/Makefile:1285: prepare] Error 2
make: *** [Makefile:248: __sub-make] Error 2
[ Naresh provided the draft diff [1].
Ben explained [2]:
FDPIC is only relevant with no-MMU targets, and then only for userspace.
When configured for the arm-*-uclinuxfdpiceabi target, GCC enables FDPIC
by default to facilitate compiling userspace programs. FDPIC is never
used for the kernel, and we pass -mno-fdpic when building the kernel to
override the default and make sure FDPIC is disabled.
and [3]:
-mno-fdpic disables a GCC feature that we don't want for kernel builds.
clang does not support this feature, so it always behaves as though
-mno-fdpic is passed. Therefore, it should be fine to mix the two, at
least as far as FDPIC is concerned.
[1] https://lore.kernel.org/rust-for-linux/CA+G9fYt4otQK4pHv8pJBW9e28yHSGCDncKquwuJiJ_1ou0pq0w@mail.gmail.com/
[2] https://lore.kernel.org/rust-for-linux/aAKrq2InExQk7f_k@dell-precision-5540/
[3] https://lore.kernel.org/rust-for-linux/aAo_F_UP1Gd4jHlZ@dell-precision-5540/
- Miguel ]
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Closes: https://lore.kernel.org/all/CA+G9fYvOanQBYXKSg7C6EU30k8sTRC0JRPJXYu7wWK51w38QUQ@mail.gmail.com/
Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Acked-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Rudraksha Gupta <guptarud@gmail.com>
Link: https://lore.kernel.org/r/20250522-rust-mno-fdpic-arm-fix-v2-1-a6f691d9c198@gmail.com
[ Reworded title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 249c3a0e53 ]
Place cleanup_module() in .exit.text section. Currently,
cleanup_module() is likely placed in the .text section. It's
inconsistent with the layout of C modules, where cleanup_module() is
placed in .exit.text.
[ Boqun asked for an example of how the section changed to be
put in the log. Tomonori provided the following examples:
C module:
$ objdump -t ~/build/x86/drivers/block/loop.o|grep clean
0000000000000000 l O .exit.data 0000000000000008 __UNIQUE_ID___addressable_cleanup_module412
0000000000000000 g F .exit.text 000000000000009c cleanup_module
Rust module without this patch:
$ objdump -t ~/build/x86/samples/rust/rust_minimal.o|grep clean
00000000000002b0 g F .text 00000000000000c6 cleanup_module
0000000000000000 g O .exit.data 0000000000000008 _R...___UNIQUE_ID___addressable_cleanup_module
Rust module with this patch:
$ objdump -t ~/build/x86/samples/rust/rust_minimal.o|grep clean
0000000000000000 g F .exit.text 00000000000000c6 cleanup_module
0000000000000000 g O .exit.data 0000000000000008 _R...___UNIQUE_ID___addressable_cleanup_module
- Miguel ]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Acked-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lore.kernel.org/r/20250308044506.14458-1-fujita.tomonori@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit f4daa80d6b upstream.
Rust 1.87 (released on 2025-05-15) compiles core library with edition
2024 instead of 2021 [1]. Ensure that the edition matches libcore's
expectation to avoid potential breakage.
[ J3m3 reported in Zulip [2] that the `rust-analyzer` target was
broken after this patch -- indeed, we need to avoid `core-cfgs`
since those are passed to the `rust-analyzer` target.
So, instead, I tweaked the patch to create a new `core-edition`
variable and explicitly mention the `--edition` flag instead of
reusing `core-cfg`s.
In addition, pass a new argument using this new variable to
`generate_rust_analyzer.py` so that we set the right edition there.
By the way, for future reference: the `filter-out` change is needed
for Rust < 1.87, since otherwise we would skip the `--edition=2021`
we just added, ending up with no edition flag, and thus the compiler
would default to the 2015 one.
[2] https://rust-for-linux.zulipchat.com/#narrow/channel/291565/topic/x/near/520206547
- Miguel ]
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/138162 [1]
Reported-by: est31 <est31@protonmail.com>
Closes: https://github.com/Rust-for-Linux/linux/issues/1163
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20250517085600.2857460-1-gary@garyguo.net
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
[ Solved conflicts for 6.12.y backport. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 211dcf7785 upstream.
Starting with Rust 1.88.0 (expected 2025-06-26) [1], `rustc` may move
back the `uninlined_format_args` to `style` from `pedantic` (it was
there waiting for rust-analyzer suppotr), and thus we will start to see
lints like:
warning: variables can be used directly in the `format!` string
--> rust/macros/kunit.rs:105:37
|
105 | let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{}", test);
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
help: change this to
|
105 - let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{}", test);
105 + let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{test}");
There is even a case that is a pure removal:
warning: variables can be used directly in the `format!` string
--> rust/macros/module.rs:51:13
|
51 | format!("{field}={content}\0", field = field, content = content)
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#uninlined_format_args
help: change this to
|
51 - format!("{field}={content}\0", field = field, content = content)
51 + format!("{field}={content}\0")
The lints all seem like nice cleanups, thus just apply them.
We may want to disable `allow-mixed-uninlined-format-args` in the future.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust-clippy/pull/14160 [1]
Acked-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250502140237.1659624-6-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7129ea6e24 upstream.
Starting with Rust 1.88.0 (expected 2025-06-26) [1][2], `rustc` may
introduce a new lint that catches unnecessary transmutes, e.g.:
error: unnecessary transmute
--> rust/uapi/uapi_generated.rs:23242:18
|
23242 | unsafe { ::core::mem::transmute(self._bitfield_1.get(0usize, 1u8) as u8) }
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace this with: `(self._bitfield_1.get(0usize, 1u8) as u8 == 1)`
|
= note: `-D unnecessary-transmutes` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(unnecessary_transmutes)]`
There are a lot of them (at least 300), but luckily they are all in
`bindgen`-generated code.
Thus clean all up by allowing it there.
Since unknown lints trigger a lint itself in older compilers, do it
conditionally so that we can keep the `unknown_lints` lint enabled.
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/136083 [1]
Link: https://github.com/rust-lang/rust/issues/136067 [2]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20250502140237.1659624-4-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 53bd978016 upstream.
The `FwFunc` struct contains an function with a char pointer argument,
for which a `*const u8` pointer was used. This is not really the
"proper" type for this, so use a `*const kernel::ffi::c_char` pointer
instead.
This has no real functionality changes, since now `kernel::ffi::c_char`
(which bindgen uses for `char`) is now a type alias to `u8` anyways,
but before commit 1bae8729e5 ("rust: map `long` to `isize` and `char`
to `u8`") the concrete type of `kernel::ffi::c_char` depended on the
architecture (However all supported architectures at the time mapped to
`i8`).
This caused problems on the v6.13 tag when building for 32 bit arm (with
my patches), since back then `*const i8` was used in the function
argument and the function that bindgen generated used
`*const core::ffi::c_char` which Rust mapped to `*const u8` on 32 bit
arm. The stable v6.13.y branch does not have this issue since commit
1bae8729e5 ("rust: map `long` to `isize` and `char` to `u8`") was
backported.
This caused the following build error:
```
error[E0308]: mismatched types
--> rust/kernel/firmware.rs:20:4
|
20 | Self(bindings::request_firmware)
| ---- ^^^^^^^^^^^^^^^^^^^^^^^^^^ expected fn pointer, found fn item
| |
| arguments to this function are incorrect
|
= note: expected fn pointer `unsafe extern "C" fn(_, *const i8, _) -> _`
found fn item `unsafe extern "C" fn(_, *const u8, _) -> _ {request_firmware}`
note: tuple struct defined here
--> rust/kernel/firmware.rs:14:8
|
14 | struct FwFunc(
| ^^^^^^
error[E0308]: mismatched types
--> rust/kernel/firmware.rs:24:14
|
24 | Self(bindings::firmware_request_nowarn)
| ---- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected fn pointer, found fn item
| |
| arguments to this function are incorrect
|
= note: expected fn pointer `unsafe extern "C" fn(_, *const i8, _) -> _`
found fn item `unsafe extern "C" fn(_, *const u8, _) -> _ {firmware_request_nowarn}`
note: tuple struct defined here
--> rust/kernel/firmware.rs:14:8
|
14 | struct FwFunc(
| ^^^^^^
error[E0308]: mismatched types
--> rust/kernel/firmware.rs:64:45
|
64 | let ret = unsafe { func.0(pfw as _, name.as_char_ptr(), dev.as_raw()) };
| ------ ^^^^^^^^^^^^^^^^^^ expected `*const i8`, found `*const u8`
| |
| arguments to this function are incorrect
|
= note: expected raw pointer `*const i8`
found raw pointer `*const u8`
error: aborting due to 3 previous errors
```
Fixes: de6582833d ("rust: add firmware abstractions")
Cc: stable@vger.kernel.org
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250413-rust_arm_fix_fw_abstaction-v3-1-8dd7c0bbcd47@gmail.com
[ Add firmware prefix to commit subject. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 901b3290bd ]
Without this change, the rest of this series will emit the following
error message:
error[E0308]: `if` and `else` have incompatible types
--> <linux>/rust/kernel/print.rs:22:22
|
21 | #[export]
| --------- expected because of this
22 | unsafe extern "C" fn rust_fmt_argument(
| ^^^^^^^^^^^^^^^^^ expected `u8`, found `i8`
|
= note: expected fn item `unsafe extern "C" fn(*mut u8, *mut u8, *mut c_void) -> *mut u8 {bindings::rust_fmt_argument}`
found fn item `unsafe extern "C" fn(*mut i8, *mut i8, *const c_void) -> *mut i8 {print::rust_fmt_argument}`
The error may be different depending on the architecture.
To fix this, change the void pointer argument to use a const pointer,
and change the imports to use crate::ffi instead of core::ffi for
integer types.
Fixes: 787983da77 ("vsprintf: add new `%pA` format specifier")
Reviewed-by: Tamir Duberstein <tamird@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250303-export-macro-v3-1-41fbad85a27f@google.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6933c1067f ]
Several pr_info! calls in rust/kernel/init.rs (both in code examples
and macro documentation) were missing a newline, causing logs to
run together. This commit updates these calls to include a trailing
newline, improving readability and consistency with the C side.
Fixes: 6841d45a30 ("rust: init: add `stack_pin_init!` macro")
Fixes: 7f8977a7fe ("rust: init: add `{pin_}chain` functions to `{Pin}Init<T, E>`")
Fixes: d0fdc39612 ("rust: init: add `PinnedDrop` trait and macros")
Fixes: 4af84c6a85 ("rust: init: update expanded macro explanation")
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://github.com/Rust-for-Linux/linux/issues/1139
Signed-off-by: Alban Kurti <kurti@invicto.ai>
Link: https://lore.kernel.org/r/20250206-printing_fix-v3-3-a85273b501ae@invicto.ai
[ Replaced Closes with Link since it fixes part of the issue. Added
one more Fixes tag (still same set of stable kernels). - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ff64846bee upstream.
ISO C's `aligned_alloc` is partially implementation-defined; on some
systems it inherits stricter requirements from POSIX's `posix_memalign`.
This causes the call added in commit dd09538fb4 ("rust: alloc:
implement `Cmalloc` in module allocator_test") to fail on macOS because
it doesn't meet the requirements of `posix_memalign`.
Adjust the call to meet the POSIX requirement and add a comment. This
fixes failures in `make rusttest` on macOS.
Acked-by: Danilo Krummrich <dakr@kernel.org>
Cc: stable@vger.kernel.org
Fixes: dd09538fb4 ("rust: alloc: implement `Cmalloc` in module allocator_test")
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20250213-aligned-alloc-v7-1-d2a2d0be164b@gmail.com
[ Added Cc: stable. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1bae8729e5 upstream.
The following FFI types are replaced compared to `core::ffi`:
1. `char` type is now always mapped to `u8`, since kernel uses
`-funsigned-char` on the C code. `core::ffi` maps it to platform
default ABI, which can be either signed or unsigned.
2. `long` is now always mapped to `isize`. It's very common in the
kernel to use `long` to represent a pointer-sized integer, and in
fact `intptr_t` is a typedef of `long` in the kernel. Enforce this
mapping rather than mapping to `i32/i64` depending on platform can
save us a lot of unnecessary casts.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240913213041.395655-5-gary@garyguo.net
[ Moved `uaccess` changes from the next commit, since they were
irrefutable patterns that Rust >= 1.82.0 warns about. Reworded
slightly and reformatted a few documentation comments. Rebased on
top of `rust-next`. Added the removal of two casts to avoid Clippy
warnings. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d072acda48 upstream.
Currently FFI integer types are defined in libcore. This commit creates
the `ffi` crate and asks bindgen to use that crate for FFI integer types
instead of `core::ffi`.
This commit is preparatory and no type changes are made in this commit
yet.
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-4-gary@garyguo.net
[ Added `rustdoc`, `rusttest` and KUnit tests support. Rebased on top of
`rust-next` (e.g. migrated more `core::ffi` cases). Reworded crate
docs slightly and formatted. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2fd6f55c04 upstream.
Currently bindgen has special logic to recognise `size_t` and `ssize_t`
and map them to Rust `usize` and `isize`. Similarly, `ptrdiff_t` is
mapped to `isize`.
However this falls short for `__kernel_size_t`, `__kernel_ssize_t` and
`__kernel_ptrdiff_t`. To ensure that they are mapped to usize/isize
rather than 32/64 integers depending on platform, blocklist them in
bindgen parameters and manually provide their definition.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Link: https://lore.kernel.org/r/20240913213041.395655-3-gary@garyguo.net
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 75c1fd41a6 upstream.
Without `-fno-builtin`, for functions like memcpy/memmove (and many
others), bindgen seems to be using the clang-provided prototype. This
prototype is ABI-wise compatible, but the issue is that it does not have
the same information as the source code w.r.t. typedefs.
For example, bindgen generates the following:
extern "C" {
pub fn strlen(s: *const core::ffi::c_char) -> core::ffi::c_ulong;
}
note that the return type is `c_ulong` (i.e. unsigned long), despite the
size_t-is-usize behavior (this is default, and we have not opted out
from it using --no-size_t-is-usize).
Similarly, memchr's size argument should be of type `__kernel_size_t`,
but bindgen generates `c_ulong` directly.
We want to ensure any `size_t` is translated to Rust `usize` so that we
can avoid having them be different type on 32-bit and 64-bit
architectures, and hence would require a lot of excessive type casts
when calling FFI functions.
I found that this bindgen behavior (which probably is caused by
libclang) can be disabled by `-fno-builtin`. Using the flag for compiled
code can result in less optimisation because compiler cannot assume
about their properties anymore, but this should not affect bindgen.
[ Trevor asked: "I wonder how reliable this behavior is. Maybe bindgen
could do a better job controlling this, is there an open issue?".
Gary replied: ..."apparently this is indeed the suggested approach in
https://github.com/rust-lang/rust-bindgen/issues/1770". - Miguel ]
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-2-gary@garyguo.net
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b2c261fa86 upstream.
Previously, the rusttest target for the macros crate did not specify
the dependencies necessary to run the rustdoc tests. These tests rely on
the kernel crate, so add the dependencies.
Signed-off-by: Ethan D. Twardy <ethan.twardy@gmail.com>
Link: https://github.com/Rust-for-Linux/linux/issues/1076
Link: https://lore.kernel.org/r/20240704145607.17732-2-ethan.twardy@gmail.com
[ Rebased (`alloc` is gone nowadays, sysroot handling is simpler) and
simplified (reused `rustdoc_test` rule instead of adding a new one,
no need for `rustdoc-compiler_builtins`, removed unneeded `macros`
explicit path). Made `vtable` example fail (avoiding to increase
the complexity in the `rusttest` target). Removed unstable
`-Zproc-macro-backtrace` option. Reworded accordingly. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 392e34b6bc upstream.
Now that we have our own `Allocator`, `Box` and `Vec` types we can remove
Rust's `alloc` crate and the `new_uninit` unstable feature.
Also remove `Kmalloc`'s `GlobalAlloc` implementation -- we can't remove
this in a separate patch, since the `alloc` crate requires a
`#[global_allocator]` to set, that implements `GlobalAlloc`.
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-29-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit eb6f92cd3f upstream.
The current implementation of tests in str.rs use `format!` to format
strings for comparison, which, internally, creates a new `String`.
In order to prepare for getting rid of Rust's alloc crate, we have to
cut this dependency. Instead, implement `format!` for `CString`.
Note that for userspace tests, `Kmalloc`, which is backing `CString`'s
memory, is just a type alias to `Cmalloc`.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-27-dakr@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dd09538fb4 upstream.
So far the kernel's `Box` and `Vec` types can't be used by userspace
test cases, since all users of those types (e.g. `CString`) use kernel
allocators for instantiation.
In order to allow userspace test cases to make use of such types as
well, implement the `Cmalloc` allocator within the allocator_test module
and type alias all kernel allocators to `Cmalloc`. The `Cmalloc`
allocator uses libc's `realloc()` function as allocator backend.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-26-dakr@kernel.org
[ Removed the temporary `allow(dead_code)` as discussed in the list and
fixed typo, added backticks. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 93e602310f upstream.
Currently, we can't implement `FromIterator`. There are a couple of
issues with this trait in the kernel, namely:
- Rust's specialization feature is unstable. This prevents us to
optimize for the special case where `I::IntoIter` equals `Vec`'s
`IntoIter` type.
- We also can't use `I::IntoIter`'s type ID either to work around this,
since `FromIterator` doesn't require this type to be `'static`.
- `FromIterator::from_iter` does return `Self` instead of
`Result<Self, AllocError>`, hence we can't properly handle allocation
failures.
- Neither `Iterator::collect` nor `FromIterator::from_iter` can handle
additional allocation flags.
Instead, provide `IntoIter::collect`, such that we can at least convert
`IntoIter` into a `Vec` again.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-19-dakr@kernel.org
[ Added newline in documentation, changed case of section to be
consistent with an existing one, fixed typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1d1d223aa3 upstream.
Implement `IntoIterator` for `Vec`, `Vec`'s `IntoIter` type, as well as
`Iterator` for `IntoIter`.
`Vec::into_iter` disassembles the `Vec` into its raw parts; additionally,
`IntoIter` keeps track of a separate pointer, which is incremented
correspondingly as the iterator advances, while the length, or the count
of elements, is decremented.
This also means that `IntoIter` takes the ownership of the backing
buffer and is responsible to drop the remaining elements and free the
backing buffer, if it's dropped.
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-18-dakr@kernel.org
[ Fixed typos. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2aac4cd7da upstream.
`Vec` provides a contiguous growable array type with contents allocated
with the kernel's allocators (e.g. `Kmalloc`, `Vmalloc` or `KVmalloc`).
In contrast to Rust's stdlib `Vec` type, the kernel `Vec` type considers
the kernel's GFP flags for all appropriate functions, always reports
allocation failures through `Result<_, AllocError>` and remains
independent from unstable features.
[ This patch starts using a new unstable feature, `inline_const`, but
it was stabilized in Rust 1.79.0, i.e. the next version after the
minimum one, thus it will not be an issue. - Miguel ]
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-17-dakr@kernel.org
[ Cleaned `rustdoc` unescaped backtick warning, added a couple more
backticks elsewhere, fixed typos, sorted `feature`s, rewrapped
documentation lines. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9e7bbfa182 upstream.
When allocating memory for arrays using allocators, the `Layout::array`
function is typically used. It returns a result, since the given size
might be too big. However, `Vec` and its iterators store their allocated
capacity and thus they already did check that the size is not too big.
The `ArrayLayout` type provides this exact behavior, as it can be
infallibly converted into a `Layout`. Instead of a `usize` capacity,
`Vec` and other similar array-storing types can use `ArrayLayout`
instead.
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20241004154149.93856-16-dakr@kernel.org
[ Formatted a few comments. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
