We must not drop the device private data on shutdown(); none of the
registrations attached to devres that might access the device private
data are released before shutdown() is called.
Hence, freeing the device private data on shutdown() can cause UAF bugs.
Fixes: 57c5bd9aee ("rust: i2c: add basic I2C device and driver abstractions")
Acked-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Igor Korotin <igor.korotin.linux@gmail.com>
Link: https://patch.msgid.link/20260107103511.570525-2-dakr@kernel.org
Signed-off-by: Danilo Krummrich <dakr@kernel.org>
`ModuleParamAccess` uses `SetOnce`, which depends on the helper functions
so the `macros` crate example under `rusttest` fails to build:
---- rust/macros/lib.rs - module (line 62) stdout ----
error: linking with `cc` failed: exit status: 1
|
= note: "cc" "-m64" ...
= note: some arguments are omitted. use `--verbose` to show all linker arguments
= note: rust-lld: error: undefined symbol: rust_helper_atomic_try_cmpxchg_relaxed
>>> referenced by kernel.ecd446ce39a5fcbb-cgu.3
>>> kernel.kernel.ecd446ce39a5fcbb-cgu.3.rcgu.o:(kernel::sync::set_once::SetOnce$LT$T$GT$::populate::h8b02644e30bd70bc) in archive ./rust/test/libkernel.rlib
rust-lld: error: undefined symbol: rust_helper_atomic_set_release
>>> referenced by kernel.ecd446ce39a5fcbb-cgu.3
>>> kernel.kernel.ecd446ce39a5fcbb-cgu.3.rcgu.o:(kernel::sync::set_once::SetOnce$LT$T$GT$::populate::h8b02644e30bd70bc) in archive ./rust/test/libkernel.rlib
collect2: error: ld returned 1 exit status
Thus ignore that example to fix the error.
[ Only the first one is needed (the other example does not use
parameters), so we can keep it enabled. Thus I removed that second
deletion (and reworded a bit).
We may want to do something better here later on; on the other hand,
we should get KUnit tests for `macros` too eventually, so we may end
up removing or repurposing that target anyway, so it is not a big deal.
- Miguel ]
Reported-by: Miguel Ojeda <ojeda@kernel.org>
Closes: https://lore.kernel.org/rust-for-linux/CANiq72mEYacdZmHKvpbahJzO_X_qqYyiSiSTYaWEQZAfp6sbxg@mail.gmail.com/
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Fixes: 0b24f9740f ("rust: module: update the module macro with module parameter support")
Link: https://patch.msgid.link/20251210.082603.290476643413141778.fujita.tomonori@gmail.com
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
On 32-bit ARM, you may encounter linker errors such as this one:
ld.lld: error: undefined symbol: _find_next_zero_bit
>>> referenced by rust_binder_main.43196037ba7bcee1-cgu.0
>>> drivers/android/binder/rust_binder_main.o:(<rust_binder_main::process::Process>::insert_or_update_handle) in archive vmlinux.a
>>> referenced by rust_binder_main.43196037ba7bcee1-cgu.0
>>> drivers/android/binder/rust_binder_main.o:(<rust_binder_main::process::Process>::insert_or_update_handle) in archive vmlinux.a
This error occurs because even though the functions are declared by
include/linux/find.h, the definition is #ifdef'd out on 32-bit ARM. This
is because arch/arm/include/asm/bitops.h contains:
#define find_first_zero_bit(p,sz) _find_first_zero_bit_le(p,sz)
#define find_next_zero_bit(p,sz,off) _find_next_zero_bit_le(p,sz,off)
#define find_first_bit(p,sz) _find_first_bit_le(p,sz)
#define find_next_bit(p,sz,off) _find_next_bit_le(p,sz,off)
And the underscore-prefixed function is conditional on #ifndef of the
non-underscore-prefixed name, but the declaration in find.h is *not*
conditional on that #ifndef.
To fix the linker error, we ensure that the symbols in question exist
when compiling Rust code. We do this by defining them in rust/helpers/
whenever the normal definition is #ifndef'd out.
Note that these helpers are somewhat unusual in that they do not have
the rust_helper_ prefix that most helpers have. Adding the rust_helper_
prefix does not compile, as 'bindings::_find_next_zero_bit()' will
result in a call to a symbol called _find_next_zero_bit as defined by
include/linux/find.h rather than a symbol with the rust_helper_ prefix.
This is because when a symbol is present in both include/ and
rust/helpers/, the one from include/ wins under the assumption that the
current configuration is one where that helper is unnecessary. This
heuristic fails for _find_next_zero_bit() because the header file always
declares it even if the symbol does not exist.
The functions still use the __rust_helper annotation. This lets the
wrapper function be inlined into Rust code even if full kernel LTO is
not used once the patch series for that feature lands.
Yury: arches are free to implement they own find_bit() functions. Most
rely on generic implementation, but arm32 and m86k - not; so they require
custom handling. Alice confirmed it fixes the build for both.
Cc: stable@vger.kernel.org
Fixes: 6cf93a9ed3 ("rust: add bindings for bitops.h")
Reported-by: Andreas Hindborg <a.hindborg@kernel.org>
Closes: https://rust-for-linux.zulipchat.com/#narrow/channel/x/topic/x/near/561677301
Tested-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Dirk Behme <dirk.behme@de.bosch.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Merge series from Andreas Kemnade <andreas@kemnade.info>:
Add a driver for the TPS65185 regulator which provides the
comparatively high voltages needed for electronic paper displays.
Datasheet for the TPS65185 is at https://www.ti.com/lit/gpn/tps65185
To simplify things, include the hwmon part directly which is only
one temperature sensor and there are no other functions besides regulators
in this chip.
Merge series from André Draszik <andre.draszik@linaro.org>:
With these attached patches it becomes possible again to support
hardware designs with multiple PMICs where individual rails of each act
as required supplies for rails of the other (due to the latter being
e.g. always-on), and vice-versa.
Google Pixel 6 and 6 Pro (oriole and raven) are examples of such
designs.
Rather than returning -EPORBE_DEFER in regulator_register() when
set_machine_constraints() fails with -EPROBE_DEFER (due to missing
required supplies), we still allow rail registration and try to
reresolve supplies each time a new rail gets registered.
This is implemented using a bus (regulator bus), which allows the core
to reresolve supplies for regulators that still need them whenever new
regulators (i.e. devices) are added.
Using a bus also solves existing problems around late resolution of
supplies as mentioned in the commit message introducing that bus.
The series starts with a few bug fixes and the last two commits
implement the changes mentioned above, but do depend on the bug fixes.
Pull driver core fixes from Danilo Krummrich:
- Fix swapped example values for the `family` and `machine` attributes
in the sysfs SoC bus ABI documentation
- Fix Rust build and intra-doc issues when optional subsystems
(CONFIG_PCI, CONFIG_AUXILIARY_BUS, CONFIG_PRINTK) are disabled
- Fix typos and incorrect safety comments in Rust PCI, DMA, and
device ID documentation
* tag 'driver-core-6.19-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
rust: device: Remove explicit import of CStrExt
rust: pci: fix typos in Bar struct's comments
rust: device: fix broken intra-doc links
rust: dma: fix broken intra-doc links
rust: driver: fix broken intra-doc links to example driver types
rust: device_id: replace incorrect word in safety documentation
rust: dma: remove incorrect safety documentation
docs: ABI: sysfs-devices-soc: Fix swapped sample values
Add atomic xchg and cmpxchg operation support for i8 and i16 types
with tests.
Note that since the current implementation of
Atomic::<{i8,i16}>::{load,store}() is READ_ONCE()/WRITE_ONCE()-based.
The atomicity between load/store and xchg/cmpxchg is only guaranteed if
the architecture has native RmW support, hence i8/i16 is currently
AtomicImpl only when CONFIG_ARCH_SUPPORTS_ATOMIC_RWM=y.
[boqun: Make i8/i16 AtomicImpl only when
CONFIG_ARCH_SUPPORTS_ATOMIC_RWM=y]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251228120546.1602275-4-fujita.tomonori@gmail.com
Rework the internal AtomicOps macro plumbing to generate per-type
implementations from a mapping list.
Capture the trait definition once and reuse it for both declaration
and per-type impl expansion to reduce duplication and keep future
extensions simple.
This is a preparatory refactor for enabling i8/i16 atomics cleanly.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251228120546.1602275-2-fujita.tomonori@gmail.com
Add READ_ONCE/WRITE_ONCE based helpers for i8 and i16 types to support
relaxed atomic operations in Rust.
While relaxed operations could be implemented purely in Rust using
read_volatile() and write_volatile(), using C's READ_ONCE() and
WRITE_ONCE() macros ensures complete consistency with the kernel
memory model.
These helpers expose different symbol names than their C counterparts
so they are split into atomic_ext.c instead of atomic.c. The symbol
names; the names make the interface Rust/C clear, consistent with
i32/i64.
[boqun: Rename the functions from {load,store} to {read,set} to avoid
future adjustment]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251211113826.1299077-3-fujita.tomonori@gmail.com
Add helper functions to expose smp_load_acquire() and
smp_store_release() for i8 and i16 types.
The smp_load_acquire() and smp_store_release() macros require type
information (sizeof) to generate appropriate architecture-specific
memory ordering instructions. Therefore, separate helper functions are
needed for each type size.
These helpers expose different symbol names than their C counterparts
so they are split into atomic_ext.c instead of atomic.c. The symbol
names; atomic_[i8|i16]_read_acquire and atomic_[i8|i16]_set_release
makes the interface Rust/C clear, consistent with i32/i64.
These helpers will be used by the upcoming Atomic<i8> and Atomic<i16>
implementation to provide proper Acquire/Release semantics across all
architectures.
[boqun: Rename the functions from {load,store} to {read,set} to avoid
future adjustment]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251211113826.1299077-2-fujita.tomonori@gmail.com
Implement Send and Sync for SetOnce<T> to allow it to be used across
thread boundaries.
Send: SetOnce<T> can be transferred across threads when T: Send, as
the contained value is also transferred and will be dropped on the
destination thread.
Sync: SetOnce<T> can be shared across threads when T: Sync, as
as_ref() provides shared references &T and atomic operations ensure
proper synchronization. Since the inner T may be dropped on any
thread, we also require T: Send.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
Reviewed-by: Andreas Hindborg <a.hindborg@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20251216000901.221375-1-fujita.tomonori@gmail.com
By introducing a new_static() constructor, the macro does not need to go
through MaybeUninit::uninit().assume_init(), which is a pattern that is
best avoided when possible.
The safety comment not only requires that the value is leaked, but also
that it is stored in the right portion of memory. This is so that the
lockdep static_obj() check will succeed when using this constructor. One
could argue that lockdep detects this scenario, so that safety
requirement isn't needed. However, it simplifies matters to require that
static_obj() will succeed and it's not a burdensome requirement on the
caller.
Suggested-by: Benno Lossin <lossin@kernel.org>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Reviewed-by: Benno Lossin <lossin@kernel.org>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://patch.msgid.link/20250811-lock-class-key-cleanup-v3-1-b12967ee1ca2@google.com
