[PATCH v2 00/33] rust: bump minimum Rust and `bindgen` versions

[PATCH v2 00/33] rust: bump minimum Rust and `bindgen` versions

[Miguel Ojeda]

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

Debian Trixie was released with a Rust 1.85.0 toolchain [2], which it
still uses to this day [3] (i.e. no update to Rust 1.85.1).

Debian Trixie was released with `bindgen` 0.71.1, which it also still
uses to this day [4].

Debian Trixie's release happened on 2025-08-09 [5], which means that a
fair amount of time has passed since its release for kernel developers
to upgrade.

Thus bump the minimum to the new versions, i.e.

  - Rust: 1.78.0 -> 1.85.0
  - bindgen: 0.65.1 -> 0.71.1

There are a few main parts to the series, in this order:

  - A few cleanups that can be performed before the bumps.
  - The Rust bump (and its cleanups).
  - The `bindgen` bump (and its cleanups).
  - Documentation updates.
  - The `cfi_encoding` patch, added here, which needs the bump.
  - The per-version flags support and a Clippy cleanup on top.

Link: https://lwn.net/Articles/1050174/ [1]
Link: https://www.debian.org/releases/trixie/release-notes/whats-new.en.html#desktops-and-well-known-packages [2]
Link: https://packages.debian.org/trixie/rustc [3]
Link: https://packages.debian.org/trixie/bindgen [4]
Link: https://www.debian.org/releases/trixie/ [5]
---
v1: https://lore.kernel.org/rust-for-linux/20260401114540.30108-1-ojeda@kernel.org/
v2:
  - Added patch to globally allow `incompatible_msrv` and removed the
    last instance.

  - Replaced `--remap-path-prefix` patches with one that drops the
    workaround entirely (and place it as the first one) and summarizes
    the discussion.

    I also noticed that `--remap-path-prefix` for `rustdoc` is still
    unstable (unlike `rustc`'s one), so I added it to our list as usual
    (https://github.com/Rust-for-Linux/linux/issues/2). There does not
    seem to be a tracking issue, so I asked upstream about it.

    We will need these two lines as the resolution for the conflict:

        $(RUSTDOC) $(filter-out $(skip_flags) --remap-path-scope=%,$(if $(rustdoc_host),$(rust_common_flags),$(rust_flags))) \

        $(RUSTDOC) --test $(filter-out --remap-path-scope=%,$(rust_flags)) \

  - Reworked the `extract_if` patch to use it (unstably). The feature
    last major change happened in Rust 1.85.0, so that is fine.

  - Moved `$(HOSTRUSTFLAGS)` below so that per-version flags (like
    lints) can be overridden too. Please see the details in the commit
    and my reply to v1.

  - Added `feature(extract_if)` and `feature(non_null_convenience)`
    items to https://github.com/Rust-for-Linux/linux/issues/1223.

    Then reworded the commits accordingly to include the references
    to tracking issues and PRs.

  - Other rewords, e.g. the "beyond" typo.

  - Rebased on top of `rust-next`.

  - Picked up tags.

Alice Ryhl (1):
  rust: declare cfi_encoding for lru_status

Miguel Ojeda (32):
  rust: kbuild: remove `--remap-path-prefix` workarounds
  rust: kbuild: remove "`try` keyword" workaround for `bindgen` < 0.59.2
  rust: kbuild: remove unneeded old `allow`s for generated layout tests
  gpu: nova-core: bindings: remove unneeded `cfg_attr`
  rust: bump Rust minimum supported version to 1.85.0 (Debian Trixie)
  rust: bump Clippy's MSRV and clean `incompatible_msrv` allows
  rust: allow globally `clippy::incompatible_msrv`
  rust: simplify `RUSTC_VERSION` Kconfig conditions
  rust: remove `RUSTC_HAS_SLICE_AS_FLATTENED` and simplify code
  rust: remove `RUSTC_HAS_COERCE_POINTEE` and simplify code
  rust: kbuild: remove skipping of `-Wrustdoc::unescaped_backticks`
  rust: kbuild: remove `feature(...)`s that are now stable
  rust: transmute: simplify code with Rust 1.80.0 `split_at_*checked()`
  rust: alloc: simplify with `NonNull::add()` now that it is stable
  rust: macros: simplify code using `feature(extract_if)`
  rust: block: update `const_refs_to_static` MSRV TODO comment
  rust: bump `bindgen` minimum supported version to 0.71.1 (Debian
    Trixie)
  rust: rust_is_available: remove warning for `bindgen` 0.66.[01]
  rust: rust_is_available: remove warning for `bindgen` < 0.69.5 &&
    libclang >= 19.1
  rust: kbuild: update `bindgen --rust-target` version and replace
    comment
  rust: kbuild: remove "dummy parameter" workaround for `bindgen` <
    0.71.1
  docs: rust: quick-start: openSUSE provides `rust-src` package nowadays
  docs: rust: quick-start: update Ubuntu versioned packages
  docs: rust: quick-start: update minimum Ubuntu version
  docs: rust: quick-start: add Ubuntu 26.04 LTS and remove subsection
    title
  docs: rust: quick-start: remove Gentoo "testing" note
  docs: rust: quick-start: remove Nix "unstable channel" note
  docs: rust: quick-start: remove GDB/Binutils mention
  docs: rust: general-information: simplify Kconfig example
  docs: rust: general-information: use real example
  rust: kbuild: support global per-version flags
  rust: kbuild: allow `clippy::precedence` for Rust < 1.86.0

 .clippy.toml                                  |  2 +-
 Documentation/process/changes.rst             |  4 +-
 Documentation/rust/general-information.rst    |  4 +-
 Documentation/rust/quick-start.rst            | 52 +++++++----------
 Makefile                                      | 12 +++-
 arch/Kconfig                                  |  3 +-
 arch/arm64/Kconfig                            |  8 ---
 arch/riscv/Kconfig                            |  3 -
 drivers/android/binder/Makefile               |  3 +-
 drivers/android/binder/page_range.rs          |  6 +-
 drivers/android/binder/page_range_helper.c    | 24 --------
 drivers/android/binder/page_range_helper.h    | 15 -----
 drivers/gpu/nova-core/gsp/cmdq.rs             |  6 +-
 drivers/gpu/nova-core/gsp/fw/r570_144.rs      |  3 -
 init/Kconfig                                  | 15 +----
 rust/Makefile                                 | 31 ++--------
 rust/bindgen_parameters                       |  8 +--
 rust/bindings/bindings_helper.h               |  1 -
 rust/bindings/lib.rs                          |  5 +-
 rust/kernel/alloc/allocator/iter.rs           |  8 +--
 rust/kernel/alloc/kbox.rs                     | 29 +---------
 rust/kernel/block/mq/gen_disk.rs              |  4 +-
 rust/kernel/lib.rs                            | 30 +---------
 rust/kernel/list/arc.rs                       | 22 +------
 rust/kernel/prelude.rs                        |  3 -
 rust/kernel/ptr.rs                            |  1 -
 rust/kernel/slice.rs                          | 49 ----------------
 rust/kernel/sync/arc.rs                       | 21 +------
 rust/kernel/transmute.rs                      | 35 ++---------
 rust/macros/helpers.rs                        |  1 -
 rust/macros/kunit.rs                          |  9 +--
 rust/macros/lib.rs                            |  3 +
 rust/uapi/lib.rs                              |  5 +-
 scripts/Makefile.build                        |  6 +-
 scripts/min-tool-version.sh                   |  4 +-
 scripts/rust_is_available.sh                  | 36 +-----------
 scripts/rust_is_available_bindgen_0_66.h      |  2 -
 ...ust_is_available_bindgen_libclang_concat.h |  3 -
 scripts/rust_is_available_test.py             | 58 +------------------
 39 files changed, 83 insertions(+), 451 deletions(-)
 delete mode 100644 drivers/android/binder/page_range_helper.c
 delete mode 100644 drivers/android/binder/page_range_helper.h
 delete mode 100644 rust/kernel/slice.rs
 delete mode 100644 scripts/rust_is_available_bindgen_0_66.h
 delete mode 100644 scripts/rust_is_available_bindgen_libclang_concat.h


base-commit: 36f5a2b09e650b82d7b2a106e3b93af48c2010d9
--
2.53.0

[PATCH v2 01/33] rust: kbuild: remove `--remap-path-prefix` workarounds

[Miguel Ojeda]

Commit 8cf5b3f83614 ("Revert "kbuild, rust: use -fremap-path-prefix
to make paths relative"") removed `--remap-path-prefix` from the build
system, so the workarounds are not needed anymore.

Thus remove them.

Note that the flag has landed again in parallel in this cycle in
commit dda135077ecc ("rust: build: remap path to avoid absolute path"),
together with `--remap-path-scope=macro` [1]. However, they are gated on
`rustc-option-yn, --remap-path-scope=macro`, which means they are both
only passed starting with Rust 1.95.0 [2]:

  `--remap-path-scope` is only stable in Rust 1.95, so use `rustc-option`
  to detect its presence. This feature has been available as
  `-Zremap-path-scope` for all versions that we support; however due to
  bugs in the Rust compiler, it does not work reliably until 1.94. I opted
  to not enable it for 1.94 as it's just a single version that we missed.

In turn, that means the workarounds removed here should not be needed
again (even with the flag added again above), since:

  - `rustdoc` now recognizes the `--remap-path-prefix` flag since Rust
    1.81.0 [3] (even if it is still an unstable feature [4]).

  - The Internal Compiler Error [5] that the comment mentions was fixed in
    Rust 1.87.0 [6]. We tested that was the case in a previous version
    of this series by making the workaround conditional [7][8].

...which are both older versions than Rust 1.95.0.

We will still need to skip `--remap-path-scope` for `rustdoc` though,
since `rustdoc` does not support that one yet [4].

Link: https://github.com/rust-lang/rust/issues/111540 [1]
Link: https://github.com/rust-lang/rust/pull/147611 [2]
Link: https://github.com/rust-lang/rust/pull/107099 [3]
Link: https://doc.rust-lang.org/nightly/rustdoc/unstable-features.html#--remap-path-prefix-remap-source-code-paths-in-output [4]
Link: https://github.com/rust-lang/rust/issues/138520 [5]
Link: https://github.com/rust-lang/rust/pull/138556 [6]
Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-9-ojeda@kernel.org/ [7]
Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-10-ojeda@kernel.org/ [8]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/Makefile | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/rust/Makefile b/rust/Makefile
index 96cd7d8e6ee9..16ea720e0a8e 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -145,14 +145,10 @@ rustdoc_modifiers_workaround := $(if $(call rustc-min-version,108800),-Cunsafe-a
 # Similarly, for doctests (https://github.com/rust-lang/rust/issues/146465).
 doctests_modifiers_workaround := $(rustdoc_modifiers_workaround)$(if $(call rustc-min-version,109100),$(comma)sanitizer)
 
-# `rustc` recognizes `--remap-path-prefix` since 1.26.0, but `rustdoc` only
-# since Rust 1.81.0. Moreover, `rustdoc` ICEs on out-of-tree builds since Rust
-# 1.82.0 (https://github.com/rust-lang/rust/issues/138520). Thus workaround both
-# issues skipping the flag. The former also applies to `RUSTDOC TK`.
 quiet_cmd_rustdoc = RUSTDOC $(if $(rustdoc_host),H, ) $<
       cmd_rustdoc = \
 	OBJTREE=$(abspath $(objtree)) \
-	$(RUSTDOC) $(filter-out $(skip_flags) --remap-path-prefix=%,$(if $(rustdoc_host),$(rust_common_flags),$(rust_flags))) \
+	$(RUSTDOC) $(filter-out $(skip_flags),$(if $(rustdoc_host),$(rust_common_flags),$(rust_flags))) \
 		$(rustc_target_flags) -L$(objtree)/$(obj) \
 		-Zunstable-options --generate-link-to-definition \
 		--output $(rustdoc_output) \
@@ -338,7 +334,7 @@ quiet_cmd_rustdoc_test_kernel = RUSTDOC TK $<
 	rm -rf $(objtree)/$(obj)/test/doctests/kernel; \
 	mkdir -p $(objtree)/$(obj)/test/doctests/kernel; \
 	OBJTREE=$(abspath $(objtree)) \
-	$(RUSTDOC) --test $(filter-out --remap-path-prefix=%,$(rust_flags)) \
+	$(RUSTDOC) --test $(rust_flags) \
 		-L$(objtree)/$(obj) --extern ffi --extern pin_init \
 		--extern kernel --extern build_error --extern macros \
 		--extern bindings --extern uapi \
-- 
2.53.0

[PATCH v2 02/33] rust: kbuild: remove "`try` keyword" workaround for `bindgen` < 0.59.2

[Miguel Ojeda]

There is a workaround that has not been needed, even already after commit
08ab786556ff ("rust: bindgen: upgrade to 0.65.1"), but it does not hurt.

Thus remove it.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/bindgen_parameters | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/rust/bindgen_parameters b/rust/bindgen_parameters
index fd2fd1c3cb9a..112ec197ef0a 100644
--- a/rust/bindgen_parameters
+++ b/rust/bindgen_parameters
@@ -15,10 +15,6 @@
 --opaque-type x86_msi_data
 --opaque-type x86_msi_addr_lo
 
-# `try` is a reserved keyword since Rust 2018; solved in `bindgen` v0.59.2,
-# commit 2aed6b021680 ("context: Escape the try keyword properly").
---opaque-type kunit_try_catch
-
 # If SMP is disabled, `arch_spinlock_t` is defined as a ZST which triggers a Rust
 # warning. We don't need to peek into it anyway.
 --opaque-type spinlock
-- 
2.53.0

[PATCH v2 03/33] rust: kbuild: remove unneeded old `allow`s for generated layout tests

[Miguel Ojeda]

The issue that required `allow`s for `cfg(test)` code generated by
`bindgen` for layout testing was fixed back in `bindgen` 0.60.0 [1],
so it could have been removed even before the version bump, but it does
not hurt.

Thus remove it now.

Link: https://github.com/rust-lang/rust-bindgen/pull/2203 [1]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/bindings/lib.rs | 4 ----
 rust/uapi/lib.rs     | 4 ----
 2 files changed, 8 deletions(-)

diff --git a/rust/bindings/lib.rs b/rust/bindings/lib.rs
index 19f57c5b2fa2..e18c160dad17 100644
--- a/rust/bindings/lib.rs
+++ b/rust/bindings/lib.rs
@@ -9,10 +9,6 @@
 //! using this crate.
 
 #![no_std]
-// See <https://github.com/rust-lang/rust-bindgen/issues/1651>.
-#![cfg_attr(test, allow(deref_nullptr))]
-#![cfg_attr(test, allow(unaligned_references))]
-#![cfg_attr(test, allow(unsafe_op_in_unsafe_fn))]
 #![allow(
     clippy::all,
     missing_docs,
diff --git a/rust/uapi/lib.rs b/rust/uapi/lib.rs
index 1d5fd9efb93e..821e286e0daa 100644
--- a/rust/uapi/lib.rs
+++ b/rust/uapi/lib.rs
@@ -8,10 +8,6 @@
 //! userspace APIs.
 
 #![no_std]
-// See <https://github.com/rust-lang/rust-bindgen/issues/1651>.
-#![cfg_attr(test, allow(deref_nullptr))]
-#![cfg_attr(test, allow(unaligned_references))]
-#![cfg_attr(test, allow(unsafe_op_in_unsafe_fn))]
 #![allow(
     clippy::all,
     clippy::cast_lossless,
-- 
2.53.0

[PATCH v2 04/33] gpu: nova-core: bindings: remove unneeded `cfg_attr`

[Miguel Ojeda]

These were likely copied from the `bindings` and `uapi` crates, but are
unneeded since there are no `cfg(test)`s in the bindings.

In addition, the issue that triggered the addition in those crates
originally is also fixed in `bindgen` (please see the previous commit).

Thus remove them.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 drivers/gpu/nova-core/gsp/fw/r570_144.rs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/gpu/nova-core/gsp/fw/r570_144.rs b/drivers/gpu/nova-core/gsp/fw/r570_144.rs
index e99d315ae74c..2e6f0d298756 100644
--- a/drivers/gpu/nova-core/gsp/fw/r570_144.rs
+++ b/drivers/gpu/nova-core/gsp/fw/r570_144.rs
@@ -7,9 +7,6 @@
 //! This module may not be directly used. Please abstract or re-export the needed symbols in the
 //! parent module instead.
 
-#![cfg_attr(test, allow(deref_nullptr))]
-#![cfg_attr(test, allow(unaligned_references))]
-#![cfg_attr(test, allow(unsafe_op_in_unsafe_fn))]
 #![allow(
     dead_code,
     clippy::all,
-- 
2.53.0

[PATCH v2 05/33] rust: bump Rust minimum supported version to 1.85.0 (Debian Trixie)

[Miguel Ojeda]

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

Debian Trixie was released with a Rust 1.85.0 toolchain [2], which it
still uses to this day [3] (i.e. no update to Rust 1.85.1).

Debian Trixie's release happened on 2025-08-09 [4], which means that a
fair amount of time has passed since its release for kernel developers
to upgrade.

Thus bump the minimum to the new version.

Then, in later commits, clean up most of the workarounds and other bits
that this upgrade of the minimum allows us.

pin-init was left as-is since the patches come from upstream. And the
vendored crates are unmodified, since we do not want to change those.

Note that the minimum LLVM major version for Rust 1.85.0 is LLVM 18 (the
Rust upstream binaries use LLVM 19.1.7), thus e.g. `RUSTC_LLVM_VERSION`
tests can also be updated, but there are no suitable ones to simplify.

Ubuntu 25.10 also has a recent enough Rust toolchain [5], and they also
provide versioned packages with a Rust 1.85.1 toolchain even back to
Ubuntu 22.04 LTS [6].

Link: https://lwn.net/Articles/1050174/ [1]
Link: https://www.debian.org/releases/trixie/release-notes/whats-new.en.html#desktops-and-well-known-packages [2]
Link: https://packages.debian.org/trixie/rustc [3]
Link: https://www.debian.org/releases/trixie/ [4]
Link: https://packages.ubuntu.com/search?suite=all&searchon=names&keywords=rustc [5]
Link: https://launchpad.net/ubuntu/+source/rustc-1.85 [6]
Acked-by: Tamir Duberstein <tamird@kernel.org>
Acked-by: Benno Lossin <lossin@kernel.org>
Acked-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Acked-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/process/changes.rst | 2 +-
 scripts/min-tool-version.sh       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index 6b373e193548..474594bd4831 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -31,7 +31,7 @@ you probably needn't concern yourself with pcmciautils.
 ====================== ===============  ========================================
 GNU C                  8.1              gcc --version
 Clang/LLVM (optional)  15.0.0           clang --version
-Rust (optional)        1.78.0           rustc --version
+Rust (optional)        1.85.0           rustc --version
 bindgen (optional)     0.65.1           bindgen --version
 GNU make               4.0              make --version
 bash                   4.2              bash --version
diff --git a/scripts/min-tool-version.sh b/scripts/min-tool-version.sh
index 99b5575c1ef7..a270ec761f64 100755
--- a/scripts/min-tool-version.sh
+++ b/scripts/min-tool-version.sh
@@ -31,7 +31,7 @@ llvm)
 	fi
 	;;
 rustc)
-	echo 1.78.0
+	echo 1.85.0
 	;;
 bindgen)
 	echo 0.65.1
-- 
2.53.0

[PATCH v2 06/33] rust: bump Clippy's MSRV and clean `incompatible_msrv` allows

[Miguel Ojeda]

Following the Rust compiler bump, we can now update Clippy's MSRV we
set in the configuration, which will improve the diagnostics it generates.

Thus do so and clean a few of the `allow`s that are not needed anymore.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 .clippy.toml                      | 2 +-
 drivers/gpu/nova-core/gsp/cmdq.rs | 6 +-----
 rust/kernel/ptr.rs                | 1 -
 rust/kernel/transmute.rs          | 2 --
 4 files changed, 2 insertions(+), 9 deletions(-)

diff --git a/.clippy.toml b/.clippy.toml
index a51de9a46380..b0a78cc8be20 100644
--- a/.clippy.toml
+++ b/.clippy.toml
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 
-msrv = "1.78.0"
+msrv = "1.85.0"
 
 check-private-items = true
 
diff --git a/drivers/gpu/nova-core/gsp/cmdq.rs b/drivers/gpu/nova-core/gsp/cmdq.rs
index 46819a82a51a..d9f69366642a 100644
--- a/drivers/gpu/nova-core/gsp/cmdq.rs
+++ b/drivers/gpu/nova-core/gsp/cmdq.rs
@@ -281,7 +281,6 @@ fn allocate_command(&mut self, size: usize) -> Result<GspCommand<'_>> {
         let (slice_1, slice_2) = {
             let (slice_1, slice_2) = self.driver_write_area();
 
-            #[allow(clippy::incompatible_msrv)]
             (slice_1.as_flattened_mut(), slice_2.as_flattened_mut())
         };
 
@@ -572,10 +571,7 @@ fn wait_for_msg(&self, timeout: Delta) -> Result<GspMessage<'_>> {
             Delta::from_millis(1),
             timeout,
         )
-        .map(|(slice_1, slice_2)| {
-            #[allow(clippy::incompatible_msrv)]
-            (slice_1.as_flattened(), slice_2.as_flattened())
-        })?;
+        .map(|(slice_1, slice_2)| (slice_1.as_flattened(), slice_2.as_flattened()))?;
 
         // Extract the `GspMsgElement`.
         let (header, slice_1) = GspMsgElement::from_bytes_prefix(slice_1).ok_or(EIO)?;
diff --git a/rust/kernel/ptr.rs b/rust/kernel/ptr.rs
index c7788656a162..91811f5e27de 100644
--- a/rust/kernel/ptr.rs
+++ b/rust/kernel/ptr.rs
@@ -81,7 +81,6 @@ pub const fn new_checked(align: usize) -> Option<Self> {
     /// This is equivalent to [`align_of`], but with the return value provided as an [`Alignment`].
     #[inline(always)]
     pub const fn of<T>() -> Self {
-        #![allow(clippy::incompatible_msrv)]
         // This cannot panic since alignments are always powers of two.
         //
         // We unfortunately cannot use `new` as it would require the `generic_const_exprs` feature.
diff --git a/rust/kernel/transmute.rs b/rust/kernel/transmute.rs
index 5711580c9f9b..b9e6eadc08f5 100644
--- a/rust/kernel/transmute.rs
+++ b/rust/kernel/transmute.rs
@@ -49,7 +49,6 @@ fn from_bytes(bytes: &[u8]) -> Option<&Self>
         let slice_ptr = bytes.as_ptr().cast::<Self>();
         let size = size_of::<Self>();
 
-        #[allow(clippy::incompatible_msrv)]
         if bytes.len() == size && slice_ptr.is_aligned() {
             // SAFETY: Size and alignment were just checked.
             unsafe { Some(&*slice_ptr) }
@@ -92,7 +91,6 @@ fn from_bytes_mut(bytes: &mut [u8]) -> Option<&mut Self>
         let slice_ptr = bytes.as_mut_ptr().cast::<Self>();
         let size = size_of::<Self>();
 
-        #[allow(clippy::incompatible_msrv)]
         if bytes.len() == size && slice_ptr.is_aligned() {
             // SAFETY: Size and alignment were just checked.
             unsafe { Some(&mut *slice_ptr) }
-- 
2.53.0

[PATCH v2 07/33] rust: allow globally `clippy::incompatible_msrv`

[Miguel Ojeda]

`clippy::incompatible_msrv` is not buying us much, and we discussed
allowing it several times in the past.

For instance, there was recently another patch sent to `allow` it where
needed [1]. While that particular case would not be needed after the
minimum version bump to 1.85.0, it is simpler to just allow it to prevent
future instances.

Thus do so, and remove the last instance of locally allowing it we have
in the tree (except the one in the vendored `proc_macro2` crate).

Note that we still keep the `msrv` config option in `clippy.toml` since
that affects other lints as well.

Link: https://lore.kernel.org/rust-for-linux/20260404212831.78971-4-jhubbard@nvidia.com/ [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Makefile               | 1 +
 rust/macros/helpers.rs | 1 -
 2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index a63684c36d60..78f5ee173eda 100644
--- a/Makefile
+++ b/Makefile
@@ -486,6 +486,7 @@ export rust_common_flags := --edition=2021 \
 			    -Wclippy::as_underscore \
 			    -Wclippy::cast_lossless \
 			    -Wclippy::ignored_unit_patterns \
+			    -Aclippy::incompatible_msrv \
 			    -Wclippy::mut_mut \
 			    -Wclippy::needless_bitwise_bool \
 			    -Aclippy::needless_lifetimes \
diff --git a/rust/macros/helpers.rs b/rust/macros/helpers.rs
index 37ef6a6f2c85..d18fbf4daa0a 100644
--- a/rust/macros/helpers.rs
+++ b/rust/macros/helpers.rs
@@ -49,7 +49,6 @@ pub(crate) fn file() -> String {
     }
 
     #[cfg(CONFIG_RUSTC_HAS_SPAN_FILE)]
-    #[allow(clippy::incompatible_msrv)]
     {
         proc_macro::Span::call_site().file()
     }
-- 
2.53.0

[PATCH v2 08/33] rust: simplify `RUSTC_VERSION` Kconfig conditions

[Miguel Ojeda]

With the Rust version bump in place, several Kconfig conditions based on
`RUSTC_VERSION` are always true.

Thus simplify them.

The minimum supported major LLVM version by our new Rust minimum version
is now LLVM 18, instead of LLVM 16. However, there are no possible
cleanups for `RUSTC_LLVM_VERSION`.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 arch/Kconfig       | 3 +--
 arch/arm64/Kconfig | 8 --------
 arch/riscv/Kconfig | 3 ---
 init/Kconfig       | 2 --
 4 files changed, 1 insertion(+), 15 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index 102ddbd4298e..84089e80584b 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -968,10 +968,9 @@ config HAVE_CFI_ICALL_NORMALIZE_INTEGERS
 config HAVE_CFI_ICALL_NORMALIZE_INTEGERS_RUSTC
 	def_bool y
 	depends on HAVE_CFI_ICALL_NORMALIZE_INTEGERS
-	depends on RUSTC_VERSION >= 107900
 	depends on ARM64 || X86_64
 	# With GCOV/KASAN we need this fix: https://github.com/rust-lang/rust/pull/129373
-	depends on (RUSTC_LLVM_VERSION >= 190103 && RUSTC_VERSION >= 108200) || \
+	depends on RUSTC_LLVM_VERSION >= 190103 || \
 		(!GCOV_KERNEL && !KASAN_GENERIC && !KASAN_SW_TAGS)
 
 config CFI_PERMISSIVE
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 38dba5f7e4d2..c91130c7fba1 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -291,14 +291,6 @@ config ARM64
 config RUSTC_SUPPORTS_ARM64
 	def_bool y
 	depends on CPU_LITTLE_ENDIAN
-	# Shadow call stack is only supported on certain rustc versions.
-	#
-	# When using the UNWIND_PATCH_PAC_INTO_SCS option, rustc version 1.80+ is
-	# required due to use of the -Zfixed-x18 flag.
-	#
-	# Otherwise, rustc version 1.82+ is required due to use of the
-	# -Zsanitizer=shadow-call-stack flag.
-	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 || RUSTC_VERSION >= 108000 && UNWIND_PATCH_PAC_INTO_SCS
 
 config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
 	def_bool CC_IS_CLANG
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 90c531e6abf5..ddc534402400 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -232,9 +232,6 @@ config RISCV
 config RUSTC_SUPPORTS_RISCV
 	def_bool y
 	depends on 64BIT
-	# Shadow call stack requires rustc version 1.82+ due to use of the
-	# -Zsanitizer=shadow-call-stack flag.
-	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200
 
 config CLANG_SUPPORTS_DYNAMIC_FTRACE
 	def_bool CC_IS_CLANG
diff --git a/init/Kconfig b/init/Kconfig
index 36d32ea44594..b8a1ab0d49d4 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -2193,9 +2193,7 @@ config RUST
 	depends on !DEBUG_INFO_BTF || (PAHOLE_HAS_LANG_EXCLUDE && !LTO)
 	depends on !CFI || HAVE_CFI_ICALL_NORMALIZE_INTEGERS_RUSTC
 	select CFI_ICALL_NORMALIZE_INTEGERS if CFI
-	depends on !CALL_PADDING || RUSTC_VERSION >= 108100
 	depends on !KASAN_SW_TAGS
-	depends on !(MITIGATION_RETHUNK && KASAN) || RUSTC_VERSION >= 108300
 	help
 	  Enables Rust support in the kernel.
 
-- 
2.53.0

[PATCH v2 09/33] rust: remove `RUSTC_HAS_SLICE_AS_FLATTENED` and simplify code

[Miguel Ojeda]

With the Rust version bump in place, the `RUSTC_HAS_SLICE_AS_FLATTENED`
Kconfig (automatic) option is always true.

Thus remove the option and simplify the code.

In particular, this includes removing the `slice` module which contained
the temporary slice helpers, i.e. the `AsFlattened` extension trait and
its `impl`s.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 init/Kconfig           |  3 ---
 rust/kernel/lib.rs     |  1 -
 rust/kernel/prelude.rs |  3 ---
 rust/kernel/slice.rs   | 49 ------------------------------------------
 4 files changed, 56 deletions(-)
 delete mode 100644 rust/kernel/slice.rs

diff --git a/init/Kconfig b/init/Kconfig
index b8a1ab0d49d4..c38f49228157 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -178,9 +178,6 @@ config LD_CAN_USE_KEEP_IN_OVERLAY
 	# https://github.com/llvm/llvm-project/pull/130661
 	def_bool LD_IS_BFD || LLD_VERSION >= 210000
 
-config RUSTC_HAS_SLICE_AS_FLATTENED
-	def_bool RUSTC_VERSION >= 108000
-
 config RUSTC_HAS_COERCE_POINTEE
 	def_bool RUSTC_VERSION >= 108400
 
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 138d846f798d..621cae75030c 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -140,7 +140,6 @@
 pub mod security;
 pub mod seq_file;
 pub mod sizes;
-pub mod slice;
 #[cfg(CONFIG_SOC_BUS)]
 pub mod soc;
 #[doc(hidden)]
diff --git a/rust/kernel/prelude.rs b/rust/kernel/prelude.rs
index e9d37f307f2a..44edf72a4a24 100644
--- a/rust/kernel/prelude.rs
+++ b/rust/kernel/prelude.rs
@@ -107,6 +107,3 @@
 // `super::std_vendor` is hidden, which makes the macro inline for some reason.
 #[doc(no_inline)]
 pub use super::dbg;
-
-#[cfg(not(CONFIG_RUSTC_HAS_SLICE_AS_FLATTENED))]
-pub use super::slice::AsFlattened;
diff --git a/rust/kernel/slice.rs b/rust/kernel/slice.rs
deleted file mode 100644
index ca2cde135061..000000000000
--- a/rust/kernel/slice.rs
+++ /dev/null
@@ -1,49 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-//! Additional (and temporary) slice helpers.
-
-/// Extension trait providing a portable version of [`as_flattened`] and
-/// [`as_flattened_mut`].
-///
-/// In Rust 1.80, the previously unstable `slice::flatten` family of methods
-/// have been stabilized and renamed from `flatten` to `as_flattened`.
-///
-/// This creates an issue for as long as the MSRV is < 1.80, as the same functionality is provided
-/// by different methods depending on the compiler version.
-///
-/// This extension trait solves this by abstracting `as_flatten` and calling the correct method
-/// depending on the Rust version.
-///
-/// This trait can be removed once the MSRV passes 1.80.
-///
-/// [`as_flattened`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened
-/// [`as_flattened_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened_mut
-#[cfg(not(CONFIG_RUSTC_HAS_SLICE_AS_FLATTENED))]
-pub trait AsFlattened<T> {
-    /// Takes a `&[[T; N]]` and flattens it to a `&[T]`.
-    ///
-    /// This is an portable layer on top of [`as_flattened`]; see its documentation for details.
-    ///
-    /// [`as_flattened`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened
-    fn as_flattened(&self) -> &[T];
-
-    /// Takes a `&mut [[T; N]]` and flattens it to a `&mut [T]`.
-    ///
-    /// This is an portable layer on top of [`as_flattened_mut`]; see its documentation for details.
-    ///
-    /// [`as_flattened_mut`]: https://doc.rust-lang.org/std/primitive.slice.html#method.as_flattened_mut
-    fn as_flattened_mut(&mut self) -> &mut [T];
-}
-
-#[cfg(not(CONFIG_RUSTC_HAS_SLICE_AS_FLATTENED))]
-impl<T, const N: usize> AsFlattened<T> for [[T; N]] {
-    #[allow(clippy::incompatible_msrv)]
-    fn as_flattened(&self) -> &[T] {
-        self.flatten()
-    }
-
-    #[allow(clippy::incompatible_msrv)]
-    fn as_flattened_mut(&mut self) -> &mut [T] {
-        self.flatten_mut()
-    }
-}
-- 
2.53.0

[PATCH v2 10/33] rust: remove `RUSTC_HAS_COERCE_POINTEE` and simplify code

[Miguel Ojeda]

With the Rust version bump in place, the `RUSTC_HAS_COERCE_POINTEE`
Kconfig (automatic) option is always true.

Thus remove the option and simplify the code.

In particular, this includes removing our use of the predecessor unstable
features we used with Rust < 1.84.0 (`coerce_unsized`, `dispatch_from_dyn`
and `unsize`).

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 init/Kconfig              |  3 ---
 rust/kernel/alloc/kbox.rs | 29 ++---------------------------
 rust/kernel/lib.rs        |  8 +-------
 rust/kernel/list/arc.rs   | 22 +---------------------
 rust/kernel/sync/arc.rs   | 21 ++-------------------
 5 files changed, 6 insertions(+), 77 deletions(-)

diff --git a/init/Kconfig b/init/Kconfig
index c38f49228157..f9fac458e4d4 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -178,9 +178,6 @@ config LD_CAN_USE_KEEP_IN_OVERLAY
 	# https://github.com/llvm/llvm-project/pull/130661
 	def_bool LD_IS_BFD || LLD_VERSION >= 210000
 
-config RUSTC_HAS_COERCE_POINTEE
-	def_bool RUSTC_VERSION >= 108400
-
 config RUSTC_HAS_SPAN_FILE
 	def_bool RUSTC_VERSION >= 108800
 
diff --git a/rust/kernel/alloc/kbox.rs b/rust/kernel/alloc/kbox.rs
index 622b3529edfc..bd6da02c7ab8 100644
--- a/rust/kernel/alloc/kbox.rs
+++ b/rust/kernel/alloc/kbox.rs
@@ -77,33 +77,8 @@
 /// `self.0` is always properly aligned and either points to memory allocated with `A` or, for
 /// zero-sized types, is a dangling, well aligned pointer.
 #[repr(transparent)]
-#[cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, derive(core::marker::CoercePointee))]
-pub struct Box<#[cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, pointee)] T: ?Sized, A: Allocator>(
-    NonNull<T>,
-    PhantomData<A>,
-);
-
-// This is to allow coercion from `Box<T, A>` to `Box<U, A>` if `T` can be converted to the
-// dynamically-sized type (DST) `U`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T, U, A> core::ops::CoerceUnsized<Box<U, A>> for Box<T, A>
-where
-    T: ?Sized + core::marker::Unsize<U>,
-    U: ?Sized,
-    A: Allocator,
-{
-}
-
-// This is to allow `Box<U, A>` to be dispatched on when `Box<T, A>` can be coerced into `Box<U,
-// A>`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T, U, A> core::ops::DispatchFromDyn<Box<U, A>> for Box<T, A>
-where
-    T: ?Sized + core::marker::Unsize<U>,
-    U: ?Sized,
-    A: Allocator,
-{
-}
+#[derive(core::marker::CoercePointee)]
+pub struct Box<#[pointee] T: ?Sized, A: Allocator>(NonNull<T>, PhantomData<A>);
 
 /// Type alias for [`Box`] with a [`Kmalloc`] allocator.
 ///
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 621cae75030c..66a09d77a2c4 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -39,17 +39,11 @@
 //
 // Expected to become stable.
 #![feature(arbitrary_self_types)]
+#![feature(derive_coerce_pointee)]
 //
 // To be determined.
 #![feature(used_with_arg)]
 //
-// `feature(derive_coerce_pointee)` is expected to become stable. Before Rust
-// 1.84.0, it did not exist, so enable the predecessor features.
-#![cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, feature(derive_coerce_pointee))]
-#![cfg_attr(not(CONFIG_RUSTC_HAS_COERCE_POINTEE), feature(coerce_unsized))]
-#![cfg_attr(not(CONFIG_RUSTC_HAS_COERCE_POINTEE), feature(dispatch_from_dyn))]
-#![cfg_attr(not(CONFIG_RUSTC_HAS_COERCE_POINTEE), feature(unsize))]
-//
 // `feature(file_with_nul)` is expected to become stable. Before Rust 1.89.0, it did not exist, so
 // enable it conditionally.
 #![cfg_attr(CONFIG_RUSTC_HAS_FILE_WITH_NUL, feature(file_with_nul))]
diff --git a/rust/kernel/list/arc.rs b/rust/kernel/list/arc.rs
index e1082423909c..a9a2b0178f65 100644
--- a/rust/kernel/list/arc.rs
+++ b/rust/kernel/list/arc.rs
@@ -160,7 +160,7 @@ fn try_new_list_arc(&self) -> bool {
 ///
 /// [`List`]: crate::list::List
 #[repr(transparent)]
-#[cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, derive(core::marker::CoercePointee))]
+#[derive(core::marker::CoercePointee)]
 pub struct ListArc<T, const ID: u64 = 0>
 where
     T: ListArcSafe<ID> + ?Sized,
@@ -443,26 +443,6 @@ fn as_ref(&self) -> &Arc<T> {
     }
 }
 
-// This is to allow coercion from `ListArc<T>` to `ListArc<U>` if `T` can be converted to the
-// dynamically-sized type (DST) `U`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T, U, const ID: u64> core::ops::CoerceUnsized<ListArc<U, ID>> for ListArc<T, ID>
-where
-    T: ListArcSafe<ID> + core::marker::Unsize<U> + ?Sized,
-    U: ListArcSafe<ID> + ?Sized,
-{
-}
-
-// This is to allow `ListArc<U>` to be dispatched on when `ListArc<T>` can be coerced into
-// `ListArc<U>`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T, U, const ID: u64> core::ops::DispatchFromDyn<ListArc<U, ID>> for ListArc<T, ID>
-where
-    T: ListArcSafe<ID> + core::marker::Unsize<U> + ?Sized,
-    U: ListArcSafe<ID> + ?Sized,
-{
-}
-
 /// A utility for tracking whether a [`ListArc`] exists using an atomic.
 ///
 /// # Invariants
diff --git a/rust/kernel/sync/arc.rs b/rust/kernel/sync/arc.rs
index 921e19333b89..18d6c0d62ce0 100644
--- a/rust/kernel/sync/arc.rs
+++ b/rust/kernel/sync/arc.rs
@@ -128,7 +128,7 @@
 /// # Ok::<(), Error>(())
 /// ```
 #[repr(transparent)]
-#[cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, derive(core::marker::CoercePointee))]
+#[derive(core::marker::CoercePointee)]
 pub struct Arc<T: ?Sized> {
     ptr: NonNull<ArcInner<T>>,
     // NB: this informs dropck that objects of type `ArcInner<T>` may be used in `<Arc<T> as
@@ -182,15 +182,6 @@ unsafe fn container_of(ptr: *const T) -> NonNull<ArcInner<T>> {
     }
 }
 
-// This is to allow coercion from `Arc<T>` to `Arc<U>` if `T` can be converted to the
-// dynamically-sized type (DST) `U`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T: ?Sized + core::marker::Unsize<U>, U: ?Sized> core::ops::CoerceUnsized<Arc<U>> for Arc<T> {}
-
-// This is to allow `Arc<U>` to be dispatched on when `Arc<T>` can be coerced into `Arc<U>`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T: ?Sized + core::marker::Unsize<U>, U: ?Sized> core::ops::DispatchFromDyn<Arc<U>> for Arc<T> {}
-
 // SAFETY: It is safe to send `Arc<T>` to another thread when the underlying `T` is `Sync` because
 // it effectively means sharing `&T` (which is safe because `T` is `Sync`); additionally, it needs
 // `T` to be `Send` because any thread that has an `Arc<T>` may ultimately access `T` using a
@@ -547,20 +538,12 @@ fn from(item: Pin<UniqueArc<T>>) -> Self {
 /// # Ok::<(), Error>(())
 /// ```
 #[repr(transparent)]
-#[cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, derive(core::marker::CoercePointee))]
+#[derive(core::marker::CoercePointee)]
 pub struct ArcBorrow<'a, T: ?Sized + 'a> {
     inner: NonNull<ArcInner<T>>,
     _p: PhantomData<&'a ()>,
 }
 
-// This is to allow `ArcBorrow<U>` to be dispatched on when `ArcBorrow<T>` can be coerced into
-// `ArcBorrow<U>`.
-#[cfg(not(CONFIG_RUSTC_HAS_COERCE_POINTEE))]
-impl<T: ?Sized + core::marker::Unsize<U>, U: ?Sized> core::ops::DispatchFromDyn<ArcBorrow<'_, U>>
-    for ArcBorrow<'_, T>
-{
-}
-
 impl<T: ?Sized> Clone for ArcBorrow<'_, T> {
     fn clone(&self) -> Self {
         *self
-- 
2.53.0

[PATCH v2 11/33] rust: kbuild: remove skipping of `-Wrustdoc::unescaped_backticks`

[Miguel Ojeda]

Back in Rust 1.82.0, I cleaned the `rustdoc::unescaped_backticks` lint in
upstream Rust and added tests so that hopefully it would not regress [1].

Thus we can remove it from our side given the Rust minimum version bump.

Link: https://github.com/rust-lang/rust/pull/128307 [1]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/Makefile | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/rust/Makefile b/rust/Makefile
index 16ea720e0a8e..5dc8b4cc89d1 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -75,8 +75,7 @@ core-edition := $(if $(call rustc-min-version,108700),2024,2021)
 
 core-skip_flags := \
     --edition=2021 \
-    -Wunreachable_pub \
-    -Wrustdoc::unescaped_backticks
+    -Wunreachable_pub
 
 core-flags := \
     --edition=$(core-edition) \
@@ -209,8 +208,6 @@ rustdoc-macros: $(src)/macros/lib.rs rustdoc-clean rustdoc-proc_macro2 \
     rustdoc-quote rustdoc-syn FORCE
 	+$(call if_changed,rustdoc)
 
-# Starting with Rust 1.82.0, skipping `-Wrustdoc::unescaped_backticks` should
-# not be needed -- see https://github.com/rust-lang/rust/pull/128307.
 rustdoc-core: private skip_flags = $(core-skip_flags)
 rustdoc-core: private rustc_target_flags = $(core-flags)
 rustdoc-core: $(RUST_LIB_SRC)/core/src/lib.rs rustdoc-clean FORCE
-- 
2.53.0

[PATCH v2 12/33] rust: kbuild: remove `feature(...)`s that are now stable

[Miguel Ojeda]

Now that the Rust minimum version is 1.85.0, there is no need to enable
certain features that are stable.

Thus clean them up.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/Makefile          |  2 --
 rust/kernel/lib.rs     | 21 ---------------------
 scripts/Makefile.build |  6 +-----
 3 files changed, 1 insertion(+), 28 deletions(-)

diff --git a/rust/Makefile b/rust/Makefile
index 5dc8b4cc89d1..54498cb5b851 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -86,10 +86,8 @@ proc_macro2-cfgs := \
     wrap_proc_macro \
     $(if $(call rustc-min-version,108800),proc_macro_span_file proc_macro_span_location)
 
-# Stable since Rust 1.79.0: `feature(proc_macro_byte_character,proc_macro_c_str_literals)`.
 proc_macro2-flags := \
     --cap-lints=allow \
-    -Zcrate-attr='feature(proc_macro_byte_character,proc_macro_c_str_literals)' \
     $(call cfgs-to-flags,$(proc_macro2-cfgs))
 
 quote-cfgs := \
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 66a09d77a2c4..b48221a5b4ec 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -16,27 +16,6 @@
 // Please see https://github.com/Rust-for-Linux/linux/issues/2 for details on
 // the unstable features in use.
 //
-// Stable since Rust 1.79.0.
-#![feature(generic_nonzero)]
-#![feature(inline_const)]
-#![feature(pointer_is_aligned)]
-//
-// Stable since Rust 1.80.0.
-#![feature(slice_flatten)]
-//
-// Stable since Rust 1.81.0.
-#![feature(lint_reasons)]
-//
-// Stable since Rust 1.82.0.
-#![feature(raw_ref_op)]
-//
-// Stable since Rust 1.83.0.
-#![feature(const_maybe_uninit_as_mut_ptr)]
-#![feature(const_mut_refs)]
-#![feature(const_option)]
-#![feature(const_ptr_write)]
-#![feature(const_refs_to_cell)]
-//
 // Expected to become stable.
 #![feature(arbitrary_self_types)]
 #![feature(derive_coerce_pointee)]
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 0b0245106d01..57cff77c2897 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -310,17 +310,13 @@ $(obj)/%.lst: $(obj)/%.c FORCE
 
 # The features in this list are the ones allowed for non-`rust/` code.
 #
-#   - Stable since Rust 1.79.0: `feature(inline_const)`.
-#   - Stable since Rust 1.81.0: `feature(lint_reasons)`.
-#   - Stable since Rust 1.82.0: `feature(asm_const)`,
-#     `feature(offset_of_nested)`, `feature(raw_ref_op)`.
 #   - Stable since Rust 1.87.0: `feature(asm_goto)`.
 #   - Expected to become stable: `feature(arbitrary_self_types)`.
 #   - To be determined: `feature(used_with_arg)`.
 #
 # Please see https://github.com/Rust-for-Linux/linux/issues/2 for details on
 # the unstable features in use.
-rust_allowed_features := asm_const,asm_goto,arbitrary_self_types,inline_const,lint_reasons,offset_of_nested,raw_ref_op,used_with_arg
+rust_allowed_features := arbitrary_self_types,asm_goto,used_with_arg
 
 # `--out-dir` is required to avoid temporaries being created by `rustc` in the
 # current working directory, which may be not accessible in the out-of-tree
-- 
2.53.0

[PATCH v2 13/33] rust: transmute: simplify code with Rust 1.80.0 `split_at_*checked()`

[Miguel Ojeda]

`feature(split_at_checked)` [1] has been stabilized in Rust 1.80.0 [2],
which is older than our new minimum Rust version (Rust 1.85.0).

Thus simplify the code using `split_at_*checked()`.

Link: https://github.com/rust-lang/rust/issues/119128 [1]
Link: https://github.com/rust-lang/rust/pull/124678 [2]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/kernel/transmute.rs | 33 ++++++---------------------------
 1 file changed, 6 insertions(+), 27 deletions(-)

diff --git a/rust/kernel/transmute.rs b/rust/kernel/transmute.rs
index b9e6eadc08f5..654b5ede2fe2 100644
--- a/rust/kernel/transmute.rs
+++ b/rust/kernel/transmute.rs
@@ -66,16 +66,9 @@ fn from_bytes_prefix(bytes: &[u8]) -> Option<(&Self, &[u8])>
     where
         Self: Sized,
     {
-        if bytes.len() < size_of::<Self>() {
-            None
-        } else {
-            // PANIC: We checked that `bytes.len() >= size_of::<Self>`, thus `split_at` cannot
-            // panic.
-            // TODO: replace with `split_at_checked` once the MSRV is >= 1.80.
-            let (prefix, remainder) = bytes.split_at(size_of::<Self>());
+        let (prefix, remainder) = bytes.split_at_checked(size_of::<Self>())?;
 
-            Self::from_bytes(prefix).map(|s| (s, remainder))
-        }
+        Self::from_bytes(prefix).map(|s| (s, remainder))
     }
 
     /// Converts a mutable slice of bytes to a reference to `Self`.
@@ -108,16 +101,9 @@ fn from_bytes_mut_prefix(bytes: &mut [u8]) -> Option<(&mut Self, &mut [u8])>
     where
         Self: AsBytes + Sized,
     {
-        if bytes.len() < size_of::<Self>() {
-            None
-        } else {
-            // PANIC: We checked that `bytes.len() >= size_of::<Self>`, thus `split_at_mut` cannot
-            // panic.
-            // TODO: replace with `split_at_mut_checked` once the MSRV is >= 1.80.
-            let (prefix, remainder) = bytes.split_at_mut(size_of::<Self>());
+        let (prefix, remainder) = bytes.split_at_mut_checked(size_of::<Self>())?;
 
-            Self::from_bytes_mut(prefix).map(|s| (s, remainder))
-        }
+        Self::from_bytes_mut(prefix).map(|s| (s, remainder))
     }
 
     /// Creates an owned instance of `Self` by copying `bytes`.
@@ -147,16 +133,9 @@ fn from_bytes_copy_prefix(bytes: &[u8]) -> Option<(Self, &[u8])>
     where
         Self: Sized,
     {
-        if bytes.len() < size_of::<Self>() {
-            None
-        } else {
-            // PANIC: We checked that `bytes.len() >= size_of::<Self>`, thus `split_at` cannot
-            // panic.
-            // TODO: replace with `split_at_checked` once the MSRV is >= 1.80.
-            let (prefix, remainder) = bytes.split_at(size_of::<Self>());
+        let (prefix, remainder) = bytes.split_at_checked(size_of::<Self>())?;
 
-            Self::from_bytes_copy(prefix).map(|s| (s, remainder))
-        }
+        Self::from_bytes_copy(prefix).map(|s| (s, remainder))
     }
 }
 
-- 
2.53.0

[PATCH v2 14/33] rust: alloc: simplify with `NonNull::add()` now that it is stable

[Miguel Ojeda]

Currently, we need to go through raw pointers and then re-create the
`NonNull` from the result of offsetting the raw pointer.

`feature(non_null_convenience)` [1] has been stabilized in Rust
1.80.0 [2], which is older than our new minimum Rust version
(Rust 1.85.0).

Thus, now that we bump the Rust minimum version, simplify using
`NonNull::add()` and clean the TODO note.

Link: https://github.com/rust-lang/rust/issues/117691 [1]
Link: https://github.com/rust-lang/rust/pull/124498 [2]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/kernel/alloc/allocator/iter.rs | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/rust/kernel/alloc/allocator/iter.rs b/rust/kernel/alloc/allocator/iter.rs
index 5759f86029b7..e0a70b7a744a 100644
--- a/rust/kernel/alloc/allocator/iter.rs
+++ b/rust/kernel/alloc/allocator/iter.rs
@@ -42,15 +42,9 @@ fn next(&mut self) -> Option<Self::Item> {
             return None;
         }
 
-        // TODO: Use `NonNull::add()` instead, once the minimum supported compiler version is
-        // bumped to 1.80 or later.
-        //
         // SAFETY: `offset` is in the interval `[0, (self.page_count() - 1) * page::PAGE_SIZE]`,
         // hence the resulting pointer is guaranteed to be within the same allocation.
-        let ptr = unsafe { self.buf.as_ptr().add(offset) };
-
-        // SAFETY: `ptr` is guaranteed to be non-null given that it is derived from `self.buf`.
-        let ptr = unsafe { NonNull::new_unchecked(ptr) };
+        let ptr = unsafe { self.buf.add(offset) };
 
         // SAFETY:
         // - `ptr` is a valid pointer to a `Vmalloc` allocation.
-- 
2.53.0

[PATCH v2 15/33] rust: macros: simplify code using `feature(extract_if)`

[Miguel Ojeda]

`feature(extract_if)` [1] was stabilized in Rust 1.87.0 [2], and the last
significant change happened in Rust 1.85.0 [3] when the range parameter
was added.

That is, with our new minimum version, we can start using the feature.

Thus simplify the code using the feature and remove the TODO comment.

Suggested-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/rust-for-linux/DHHVSX66206Y.3E7I9QUNTCJ8I@garyguo.net/
Link: https://github.com/rust-lang/rust/issues/43244 [1]
Link: https://github.com/rust-lang/rust/pull/137109 [2]
Link: https://github.com/rust-lang/rust/pull/133265 [3]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/macros/kunit.rs | 9 +++++----
 rust/macros/lib.rs   | 3 +++
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/rust/macros/kunit.rs b/rust/macros/kunit.rs
index 6be880d634e2..ae20ed6768f1 100644
--- a/rust/macros/kunit.rs
+++ b/rust/macros/kunit.rs
@@ -87,10 +87,11 @@ pub(crate) fn kunit_tests(test_suite: Ident, mut module: ItemMod) -> Result<Toke
             continue;
         };
 
-        // TODO: Replace below with `extract_if` when MSRV is bumped above 1.85.
-        let before_len = f.attrs.len();
-        f.attrs.retain(|attr| !attr.path().is_ident("test"));
-        if f.attrs.len() == before_len {
+        if f.attrs
+            .extract_if(.., |attr| attr.path().is_ident("test"))
+            .count()
+            == 0
+        {
             processed_items.push(Item::Fn(f));
             continue;
         }
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index 0c36194d9971..2cfd59e0f9e7 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -6,6 +6,9 @@
 // and thus add a dependency on `include/config/RUSTC_VERSION_TEXT`, which is
 // touched by Kconfig when the version string from the compiler changes.
 
+// Stable since Rust 1.87.0.
+#![feature(extract_if)]
+//
 // Stable since Rust 1.88.0 under a different name, `proc_macro_span_file`,
 // which was added in Rust 1.88.0. This is why `cfg_attr` is used here, i.e.
 // to avoid depending on the full `proc_macro_span` on Rust >= 1.88.0.
-- 
2.53.0

[PATCH v2 16/33] rust: block: update `const_refs_to_static` MSRV TODO comment

[Miguel Ojeda]

`feature(const_refs_to_static)` was stabilized in Rust 1.83.0 [1].

Thus update the comment to reflect that.

Link: https://github.com/rust-lang/rust/pull/129759 [1]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/kernel/block/mq/gen_disk.rs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index c8b0ecb17082..912cb805caf5 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -140,9 +140,7 @@ pub fn build<T: Operations>(
             devnode: None,
             alternative_gpt_sector: None,
             get_unique_id: None,
-            // TODO: Set to THIS_MODULE. Waiting for const_refs_to_static feature to
-            // be merged (unstable in rustc 1.78 which is staged for linux 6.10)
-            // <https://github.com/rust-lang/rust/issues/119618>
+            // TODO: Set to `THIS_MODULE`.
             owner: core::ptr::null_mut(),
             pr_ops: core::ptr::null_mut(),
             free_disk: None,
-- 
2.53.0

[PATCH v2 17/33] rust: bump `bindgen` minimum supported version to 0.71.1 (Debian Trixie)

[Miguel Ojeda]

As proposed in the past in e.g. LPC 2025 and the Maintainers Summit [1],
we are going to follow Debian Stable's `bindgen` versions as our minimum
supported version.

Debian Trixie was released with `bindgen` 0.71.1, which it still uses
to this day [2].

Debian Trixie's release happened on 2025-08-09 [3], which means that a
fair amount of time has passed since its release for kernel developers
to upgrade.

Thus bump the minimum to the new version.

Then, in later commits, clean up most of the workarounds and other bits
that this upgrade of the minimum allows us.

Ubuntu 25.10 also has a recent enough `bindgen` [4] (even the already
unsupported Ubuntu 25.04 had it), and they also provide versioned packages
with `bindgen` 0.71.1 back to Ubuntu 24.04 LTS [5].

Link: https://lwn.net/Articles/1050174/ [1]
Link: https://packages.debian.org/trixie/bindgen [2]
Link: https://www.debian.org/releases/trixie/ [3]
Link: https://packages.ubuntu.com/search?suite=all&searchon=names&keywords=bindgen [4]
Link: https://launchpad.net/ubuntu/+source/rust-bindgen-0.71 [5]
Acked-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/process/changes.rst | 2 +-
 scripts/min-tool-version.sh       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/process/changes.rst b/Documentation/process/changes.rst
index 474594bd4831..84156d031365 100644
--- a/Documentation/process/changes.rst
+++ b/Documentation/process/changes.rst
@@ -32,7 +32,7 @@ you probably needn't concern yourself with pcmciautils.
 GNU C                  8.1              gcc --version
 Clang/LLVM (optional)  15.0.0           clang --version
 Rust (optional)        1.85.0           rustc --version
-bindgen (optional)     0.65.1           bindgen --version
+bindgen (optional)     0.71.1           bindgen --version
 GNU make               4.0              make --version
 bash                   4.2              bash --version
 binutils               2.30             ld -v
diff --git a/scripts/min-tool-version.sh b/scripts/min-tool-version.sh
index a270ec761f64..b96ec2d379b6 100755
--- a/scripts/min-tool-version.sh
+++ b/scripts/min-tool-version.sh
@@ -34,7 +34,7 @@ rustc)
 	echo 1.85.0
 	;;
 bindgen)
-	echo 0.65.1
+	echo 0.71.1
 	;;
 *)
 	echo "$1: unknown tool" >&2
-- 
2.53.0

[PATCH v2 18/33] rust: rust_is_available: remove warning for `bindgen` 0.66.[01]

[Miguel Ojeda]

It is not possible anymore to fall into the issue that this warning was
alerting about given the `bindgen` version bump.

Thus simplify by removing the machinery behind it, including tests.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 scripts/rust_is_available.sh             | 13 ------------
 scripts/rust_is_available_bindgen_0_66.h |  2 --
 scripts/rust_is_available_test.py        | 26 +++---------------------
 3 files changed, 3 insertions(+), 38 deletions(-)
 delete mode 100644 scripts/rust_is_available_bindgen_0_66.h

diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh
index d2323de0692c..77896e31dab5 100755
--- a/scripts/rust_is_available.sh
+++ b/scripts/rust_is_available.sh
@@ -163,19 +163,6 @@ if [ "$rust_bindings_generator_cversion" -lt "$rust_bindings_generator_min_cvers
 	echo >&2 "***"
 	exit 1
 fi
-if [ "$rust_bindings_generator_cversion" -eq 6600 ] ||
-	[ "$rust_bindings_generator_cversion" -eq 6601 ]; then
-	# Distributions may have patched the issue (e.g. Debian did).
-	if ! "$BINDGEN" $(dirname $0)/rust_is_available_bindgen_0_66.h >/dev/null; then
-		echo >&2 "***"
-		echo >&2 "*** Rust bindings generator '$BINDGEN' versions 0.66.0 and 0.66.1 may not"
-		echo >&2 "*** work due to a bug (https://github.com/rust-lang/rust-bindgen/pull/2567),"
-		echo >&2 "*** unless patched (like Debian's)."
-		echo >&2 "***   Your version:     $rust_bindings_generator_version"
-		echo >&2 "***"
-		warning=1
-	fi
-fi
 
 # Check that the `libclang` used by the Rust bindings generator is suitable.
 #
diff --git a/scripts/rust_is_available_bindgen_0_66.h b/scripts/rust_is_available_bindgen_0_66.h
deleted file mode 100644
index c0431293421c..000000000000
--- a/scripts/rust_is_available_bindgen_0_66.h
+++ /dev/null
@@ -1,2 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#define A "\0"
diff --git a/scripts/rust_is_available_test.py b/scripts/rust_is_available_test.py
index 4fcc319dea84..b66fa5933844 100755
--- a/scripts/rust_is_available_test.py
+++ b/scripts/rust_is_available_test.py
@@ -54,17 +54,12 @@ else:
 """)
 
     @classmethod
-    def generate_bindgen(cls, version_stdout, libclang_stderr, version_0_66_patched=False, libclang_concat_patched=False):
+    def generate_bindgen(cls, version_stdout, libclang_stderr, libclang_concat_patched=False):
         if libclang_stderr is None:
             libclang_case = f"raise SystemExit({cls.bindgen_default_bindgen_libclang_failure_exit_code})"
         else:
             libclang_case = f"print({repr(libclang_stderr)}, file=sys.stderr)"
 
-        if version_0_66_patched:
-            version_0_66_case = "pass"
-        else:
-            version_0_66_case = "raise SystemExit(1)"
-
         if libclang_concat_patched:
             libclang_concat_case = "print('pub static mut foofoo: ::std::os::raw::c_int;')"
         else:
@@ -74,8 +69,6 @@ else:
 import sys
 if "rust_is_available_bindgen_libclang.h" in " ".join(sys.argv):
     {libclang_case}
-elif "rust_is_available_bindgen_0_66.h" in " ".join(sys.argv):
-    {version_0_66_case}
 elif "rust_is_available_bindgen_libclang_concat.h" in " ".join(sys.argv):
     {libclang_concat_case}
 else:
@@ -83,8 +76,8 @@ else:
 """)
 
     @classmethod
-    def generate_bindgen_version(cls, stdout, version_0_66_patched=False):
-        return cls.generate_bindgen(stdout, cls.bindgen_default_bindgen_libclang_stderr, version_0_66_patched)
+    def generate_bindgen_version(cls, stdout):
+        return cls.generate_bindgen(stdout, cls.bindgen_default_bindgen_libclang_stderr)
 
     @classmethod
     def generate_bindgen_libclang_failure(cls):
@@ -245,19 +238,6 @@ else:
         result = self.run_script(self.Expected.FAILURE, { "BINDGEN": bindgen })
         self.assertIn(f"Rust bindings generator '{bindgen}' is too old.", result.stderr)
 
-    def test_bindgen_bad_version_0_66_0_and_0_66_1(self):
-        for version in ("0.66.0", "0.66.1"):
-            with self.subTest(version=version):
-                bindgen = self.generate_bindgen_version(f"bindgen {version}")
-                result = self.run_script(self.Expected.SUCCESS_WITH_WARNINGS, { "BINDGEN": bindgen })
-                self.assertIn(f"Rust bindings generator '{bindgen}' versions 0.66.0 and 0.66.1 may not", result.stderr)
-
-    def test_bindgen_bad_version_0_66_0_and_0_66_1_patched(self):
-        for version in ("0.66.0", "0.66.1"):
-            with self.subTest(version=version):
-                bindgen = self.generate_bindgen_version(f"bindgen {version}", True)
-                result = self.run_script(self.Expected.SUCCESS, { "BINDGEN": bindgen })
-
     def test_bindgen_libclang_failure(self):
         bindgen = self.generate_bindgen_libclang_failure()
         result = self.run_script(self.Expected.FAILURE, { "BINDGEN": bindgen })
-- 
2.53.0

[PATCH v2 19/33] rust: rust_is_available: remove warning for `bindgen` < 0.69.5 && libclang >= 19.1

[Miguel Ojeda]

It is not possible anymore to fall into the issue that this warning was
alerting about given the `bindgen` version bump.

Thus simplify by removing the machinery behind it, including tests.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 scripts/rust_is_available.sh                  | 15 --------
 ...ust_is_available_bindgen_libclang_concat.h |  3 --
 scripts/rust_is_available_test.py             | 34 +------------------
 3 files changed, 1 insertion(+), 51 deletions(-)
 delete mode 100644 scripts/rust_is_available_bindgen_libclang_concat.h

diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh
index 77896e31dab5..cefc456c2503 100755
--- a/scripts/rust_is_available.sh
+++ b/scripts/rust_is_available.sh
@@ -214,21 +214,6 @@ if [ "$bindgen_libclang_cversion" -lt "$bindgen_libclang_min_cversion" ]; then
 	exit 1
 fi
 
-if [ "$bindgen_libclang_cversion" -ge 1900100 ] &&
-	[ "$rust_bindings_generator_cversion" -lt 6905 ]; then
-	# Distributions may have patched the issue (e.g. Debian did).
-	if ! "$BINDGEN" $(dirname $0)/rust_is_available_bindgen_libclang_concat.h | grep -q foofoo; then
-		echo >&2 "***"
-		echo >&2 "*** Rust bindings generator '$BINDGEN' < 0.69.5 together with libclang >= 19.1"
-		echo >&2 "*** may not work due to a bug (https://github.com/rust-lang/rust-bindgen/pull/2824),"
-		echo >&2 "*** unless patched (like Debian's)."
-		echo >&2 "***   Your bindgen version:  $rust_bindings_generator_version"
-		echo >&2 "***   Your libclang version: $bindgen_libclang_version"
-		echo >&2 "***"
-		warning=1
-	fi
-fi
-
 # If the C compiler is Clang, then we can also check whether its version
 # matches the `libclang` version used by the Rust bindings generator.
 #
diff --git a/scripts/rust_is_available_bindgen_libclang_concat.h b/scripts/rust_is_available_bindgen_libclang_concat.h
deleted file mode 100644
index efc6e98d0f1d..000000000000
--- a/scripts/rust_is_available_bindgen_libclang_concat.h
+++ /dev/null
@@ -1,3 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#define F(x) int x##x
-F(foo);
diff --git a/scripts/rust_is_available_test.py b/scripts/rust_is_available_test.py
index b66fa5933844..d6d54b7ea42a 100755
--- a/scripts/rust_is_available_test.py
+++ b/scripts/rust_is_available_test.py
@@ -54,23 +54,16 @@ else:
 """)
 
     @classmethod
-    def generate_bindgen(cls, version_stdout, libclang_stderr, libclang_concat_patched=False):
+    def generate_bindgen(cls, version_stdout, libclang_stderr):
         if libclang_stderr is None:
             libclang_case = f"raise SystemExit({cls.bindgen_default_bindgen_libclang_failure_exit_code})"
         else:
             libclang_case = f"print({repr(libclang_stderr)}, file=sys.stderr)"
 
-        if libclang_concat_patched:
-            libclang_concat_case = "print('pub static mut foofoo: ::std::os::raw::c_int;')"
-        else:
-            libclang_concat_case = "pass"
-
         return cls.generate_executable(f"""#!/usr/bin/env python3
 import sys
 if "rust_is_available_bindgen_libclang.h" in " ".join(sys.argv):
     {libclang_case}
-elif "rust_is_available_bindgen_libclang_concat.h" in " ".join(sys.argv):
-    {libclang_concat_case}
 else:
     print({repr(version_stdout)})
 """)
@@ -255,31 +248,6 @@ else:
         result = self.run_script(self.Expected.FAILURE, { "BINDGEN": bindgen })
         self.assertIn(f"libclang (used by the Rust bindings generator '{bindgen}') is too old.", result.stderr)
 
-    def test_bindgen_bad_libclang_concat(self):
-        for (bindgen_version, libclang_version, expected_not_patched) in (
-            ("0.69.4", "18.0.0", self.Expected.SUCCESS),
-            ("0.69.4", "19.1.0", self.Expected.SUCCESS_WITH_WARNINGS),
-            ("0.69.4", "19.2.0", self.Expected.SUCCESS_WITH_WARNINGS),
-
-            ("0.69.5", "18.0.0", self.Expected.SUCCESS),
-            ("0.69.5", "19.1.0", self.Expected.SUCCESS),
-            ("0.69.5", "19.2.0", self.Expected.SUCCESS),
-
-            ("0.70.0", "18.0.0", self.Expected.SUCCESS),
-            ("0.70.0", "19.1.0", self.Expected.SUCCESS),
-            ("0.70.0", "19.2.0", self.Expected.SUCCESS),
-        ):
-            with self.subTest(bindgen_version=bindgen_version, libclang_version=libclang_version):
-                cc = self.generate_clang(f"clang version {libclang_version}")
-                libclang_stderr = f"scripts/rust_is_available_bindgen_libclang.h:2:9: warning: clang version {libclang_version} [-W#pragma-messages], err: false"
-                bindgen = self.generate_bindgen(f"bindgen {bindgen_version}", libclang_stderr)
-                result = self.run_script(expected_not_patched, { "BINDGEN": bindgen, "CC": cc })
-                if expected_not_patched == self.Expected.SUCCESS_WITH_WARNINGS:
-                    self.assertIn(f"Rust bindings generator '{bindgen}' < 0.69.5 together with libclang >= 19.1", result.stderr)
-
-                bindgen = self.generate_bindgen(f"bindgen {bindgen_version}", libclang_stderr, libclang_concat_patched=True)
-                result = self.run_script(self.Expected.SUCCESS, { "BINDGEN": bindgen, "CC": cc })
-
     def test_clang_matches_bindgen_libclang_different_bindgen(self):
         bindgen = self.generate_bindgen_libclang("scripts/rust_is_available_bindgen_libclang.h:2:9: warning: clang version 999.0.0 [-W#pragma-messages], err: false")
         result = self.run_script(self.Expected.SUCCESS_WITH_WARNINGS, { "BINDGEN": bindgen })
-- 
2.53.0

[PATCH v2 20/33] rust: kbuild: update `bindgen --rust-target` version and replace comment

[Miguel Ojeda]

As the comment in the `Makefile` explains, previously, we needed to
limit ourselves to the list of Rust versions known by `bindgen` for its
`--rust-target` option [1].

In other words, we needed to consult the versions known by the minimum
version of `bindgen` that we supported.

Now that we bumped the minimum version of `bindgen`, that limitation
does not apply anymore since `bindgen` 0.71.0 [2].

Thus replace the comment and simply write our minimum supported Rust
version there, which is much simpler.

See commit 7a5f93ea5862 ("rust: kbuild: set `bindgen`'s Rust target
version") for more details.

Link: https://rust-lang.zulipchat.com/#narrow/channel/425075-rust-for-linux/topic/rust.20version.20on.20generated.20bindings/near/484087179 [1]
Link: https://github.com/rust-lang/rust-bindgen/pull/2993 [2]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 rust/Makefile | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

diff --git a/rust/Makefile b/rust/Makefile
index 54498cb5b851..866f9afc1b7f 100644
--- a/rust/Makefile
+++ b/rust/Makefile
@@ -441,22 +441,10 @@ endif
 # architecture instead of generating `usize`.
 bindgen_c_flags_final = $(bindgen_c_flags_lto) -fno-builtin -D__BINDGEN__
 
-# Each `bindgen` release may upgrade the list of Rust target versions. By
-# default, the highest stable release in their list is used. Thus we need to set
-# a `--rust-target` to avoid future `bindgen` releases emitting code that
-# `rustc` may not understand. On top of that, `bindgen` does not support passing
-# an unknown Rust target version.
-#
-# Therefore, the Rust target for `bindgen` can be only as high as the minimum
-# Rust version the kernel supports and only as high as the greatest stable Rust
-# target supported by the minimum `bindgen` version the kernel supports (that
-# is, if we do not test the actual `rustc`/`bindgen` versions running).
-#
-# Starting with `bindgen` 0.71.0, we will be able to set any future Rust version
-# instead, i.e. we will be able to set here our minimum supported Rust version.
+# `--rust-target` points to our minimum supported Rust version.
 quiet_cmd_bindgen = BINDGEN $@
       cmd_bindgen = \
-	$(BINDGEN) $< $(bindgen_target_flags) --rust-target 1.68 \
+	$(BINDGEN) $< $(bindgen_target_flags) --rust-target 1.85 \
 		--use-core --with-derive-default --ctypes-prefix ffi --no-layout-tests \
 		--no-debug '.*' --enable-function-attribute-detection \
 		-o $@ -- $(bindgen_c_flags_final) -DMODULE \
-- 
2.53.0

[PATCH v2 21/33] rust: kbuild: remove "dummy parameter" workaround for `bindgen` < 0.71.1

[Miguel Ojeda]

Until the version bump of `bindgen`, we needed to pass a dummy parameter
to avoid failing the `--version` call.

Thus remove it.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 init/Kconfig                 | 7 +------
 scripts/rust_is_available.sh | 8 +-------
 2 files changed, 2 insertions(+), 13 deletions(-)

diff --git a/init/Kconfig b/init/Kconfig
index f9fac458e4d4..d9b795f70a38 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -2211,12 +2211,7 @@ config RUSTC_VERSION_TEXT
 config BINDGEN_VERSION_TEXT
 	string
 	depends on RUST
-	# The dummy parameter `workaround-for-0.69.0` is required to support 0.69.0
-	# (https://github.com/rust-lang/rust-bindgen/pull/2678) and 0.71.0
-	# (https://github.com/rust-lang/rust-bindgen/pull/3040). It can be removed
-	# when the minimum version is upgraded past the latter (0.69.1 and 0.71.1
-	# both fixed the issue).
-	default "$(shell,$(BINDGEN) --version workaround-for-0.69.0 2>/dev/null)"
+	default "$(shell,$(BINDGEN) --version 2>/dev/null)"
 
 #
 # Place an empty function call at each tracepoint site. Can be
diff --git a/scripts/rust_is_available.sh b/scripts/rust_is_available.sh
index cefc456c2503..551f1ebd0dcb 100755
--- a/scripts/rust_is_available.sh
+++ b/scripts/rust_is_available.sh
@@ -121,14 +121,8 @@ fi
 # Check that the Rust bindings generator is suitable.
 #
 # Non-stable and distributions' versions may have a version suffix, e.g. `-dev`.
-#
-# The dummy parameter `workaround-for-0.69.0` is required to support 0.69.0
-# (https://github.com/rust-lang/rust-bindgen/pull/2678) and 0.71.0
-# (https://github.com/rust-lang/rust-bindgen/pull/3040). It can be removed when
-# the minimum version is upgraded past the latter (0.69.1 and 0.71.1 both fixed
-# the issue).
 rust_bindings_generator_output=$( \
-	LC_ALL=C "$BINDGEN" --version workaround-for-0.69.0 2>/dev/null
+	LC_ALL=C "$BINDGEN" --version 2>/dev/null
 ) || rust_bindings_generator_code=$?
 if [ -n "$rust_bindings_generator_code" ]; then
 	echo >&2 "***"
-- 
2.53.0

[PATCH v2 22/33] docs: rust: quick-start: openSUSE provides `rust-src` package nowadays

[Miguel Ojeda]

Both openSUSE Tumbleweed and Slowroll provide the `rust-src` package
nowadays [1].

Thus remove the version-specific one from the Quick Start guide.

Link: https://software.opensuse.org/package/rust-src?search_term=rust-src [1]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 152289f0bed2..642efce04ee8 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -84,7 +84,7 @@ openSUSE
 openSUSE Slowroll and openSUSE Tumbleweed provide recent Rust releases and thus
 they should generally work out of the box, e.g.::
 
-	zypper install rust rust1.79-src rust-bindgen clang
+	zypper install rust rust-src rust-bindgen clang
 
 
 Ubuntu
-- 
2.53.0

[PATCH v2 23/33] docs: rust: quick-start: update Ubuntu versioned packages

[Miguel Ojeda]

Now that the minimum supported Rust version is bumped, bump the versioned
Rust packages [1][2][3][4] to that version for Ubuntu in the Quick
Start guide.

In addition, add "may" to the `RUST_LIB_SRC` line since it does not look
like it is needed from a quick test in a Ubuntu 24.04 LTS container.

Link: https://packages.ubuntu.com/search?suite=all&searchon=names&keywords=rustc [1]
Link: https://packages.ubuntu.com/search?suite=all&searchon=names&keywords=bindgen [2]
Link: https://launchpad.net/ubuntu/+source/rustc-1.85 [3]
Link: https://launchpad.net/ubuntu/+source/rust-bindgen-0.71 [4]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 642efce04ee8..54fe491deb7d 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -112,33 +112,33 @@ Though Ubuntu 24.04 LTS and older versions still provide recent Rust
 releases, they require some additional configuration to be set, using
 the versioned packages, e.g.::
 
-	apt install rustc-1.80 rust-1.80-src bindgen-0.65 rustfmt-1.80 \
-		rust-1.80-clippy
-	ln -s /usr/lib/rust-1.80/bin/rustfmt /usr/bin/rustfmt-1.80
-	ln -s /usr/lib/rust-1.80/bin/clippy-driver /usr/bin/clippy-driver-1.80
+	apt install rustc-1.85 rust-1.85-src bindgen-0.71 rustfmt-1.85 \
+		rust-1.85-clippy
+	ln -s /usr/lib/rust-1.85/bin/rustfmt /usr/bin/rustfmt-1.85
+	ln -s /usr/lib/rust-1.85/bin/clippy-driver /usr/bin/clippy-driver-1.85
 
 None of these packages set their tools as defaults; therefore they should be
 specified explicitly, e.g.::
 
-	make LLVM=1 RUSTC=rustc-1.80 RUSTDOC=rustdoc-1.80 RUSTFMT=rustfmt-1.80 \
-		CLIPPY_DRIVER=clippy-driver-1.80 BINDGEN=bindgen-0.65
+	make LLVM=1 RUSTC=rustc-1.85 RUSTDOC=rustdoc-1.85 RUSTFMT=rustfmt-1.85 \
+		CLIPPY_DRIVER=clippy-driver-1.85 BINDGEN=bindgen-0.71
 
-Alternatively, modify the ``PATH`` variable to place the Rust 1.80 binaries
+Alternatively, modify the ``PATH`` variable to place the Rust 1.85 binaries
 first and set ``bindgen`` as the default, e.g.::
 
-	PATH=/usr/lib/rust-1.80/bin:$PATH
+	PATH=/usr/lib/rust-1.85/bin:$PATH
 	update-alternatives --install /usr/bin/bindgen bindgen \
-		/usr/bin/bindgen-0.65 100
-	update-alternatives --set bindgen /usr/bin/bindgen-0.65
+		/usr/bin/bindgen-0.71 100
+	update-alternatives --set bindgen /usr/bin/bindgen-0.71
 
-``RUST_LIB_SRC`` needs to be set when using the versioned packages, e.g.::
+``RUST_LIB_SRC`` may need to be set when using the versioned packages, e.g.::
 
-	RUST_LIB_SRC=/usr/src/rustc-$(rustc-1.80 --version | cut -d' ' -f2)/library
+	RUST_LIB_SRC=/usr/src/rustc-$(rustc-1.85 --version | cut -d' ' -f2)/library
 
 For convenience, ``RUST_LIB_SRC`` can be exported to the global environment.
 
-In addition, ``bindgen-0.65`` is available in newer releases (24.04 LTS and
-24.10), but it may not be available in older ones (20.04 LTS and 22.04 LTS),
+In addition, ``bindgen-0.71`` is available in newer releases (24.04 LTS),
+but it may not be available in older ones (20.04 LTS and 22.04 LTS),
 thus ``bindgen`` may need to be built manually (please see below).
 
 
-- 
2.53.0

[PATCH v2 24/33] docs: rust: quick-start: update minimum Ubuntu version

[Miguel Ojeda]

Ubuntu 25.04 is out of support [1], and Ubuntu 25.10 is the latest
supported one.

Moreover, Ubuntu 25.10 is the first that provides a recent enough Rust
given the minimum bump -- they provide 1.85.1 [2].

Thus update it.

Link: https://ubuntu.com/about/release-cycle [1]
Link: https://packages.ubuntu.com/search?keywords=rustc&searchon=names&exact=1&suite=all&section=all [2]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 54fe491deb7d..34c39f208333 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -90,7 +90,7 @@ they should generally work out of the box, e.g.::
 Ubuntu
 ******
 
-25.04
+25.10
 ~~~~~
 
 The latest Ubuntu releases provide recent Rust releases and thus they should
-- 
2.53.0

[PATCH v2 25/33] docs: rust: quick-start: add Ubuntu 26.04 LTS and remove subsection title

[Miguel Ojeda]

Ubuntu 26.04 LTS (Resolute Raccoon) is scheduled to be released in a few
weeks [1], and it has a recent enough Rust toolchain, just like Ubuntu
25.10 has [2][3].

We could update the title and the paragraph, but to simplify and to
make it more consistent with the other distributions' sections, let's
instead just remove that title. It will also reduce the differences
later on to keep it updated. Eventually, when we remove the remaining
subsection for older LTSs, Ubuntu should be a small section like the
other distributions.

Thus remove the title and add the mention of Ubuntu 26.04 LTS.

Link: https://documentation.ubuntu.com/release-notes/26.04/schedule/#resolute-raccoon-schedule [1]
Link: https://packages.ubuntu.com/search?keywords=rustc&searchon=names&exact=1&suite=all&section=all [2]
Link: https://packages.ubuntu.com/search?keywords=bindgen&searchon=names&exact=1&suite=all&section=all [3]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 34c39f208333..db08c3a03a4f 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -90,10 +90,7 @@ they should generally work out of the box, e.g.::
 Ubuntu
 ******
 
-25.10
-~~~~~
-
-The latest Ubuntu releases provide recent Rust releases and thus they should
+Ubuntu 25.10 and 26.04 LTS provide recent Rust releases and thus they should
 generally work out of the box, e.g.::
 
 	apt install rustc rust-src bindgen rustfmt rust-clippy
-- 
2.53.0

[PATCH v2 26/33] docs: rust: quick-start: remove Gentoo "testing" note

[Miguel Ojeda]

Gentoo does not need the "testing" note, since its packages are recent
enough even in the stable branch [1][2].

Thus remove it to simplify the documentation.

Link: https://packages.gentoo.org/packages/dev-lang/rust [1]
Link: https://packages.gentoo.org/packages/dev-util/bindgen [2]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index db08c3a03a4f..1518367324fe 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -57,8 +57,8 @@ of the box, e.g.::
 Gentoo Linux
 ************
 
-Gentoo Linux (and especially the testing branch) provides recent Rust releases
-and thus it should generally work out of the box, e.g.::
+Gentoo Linux provides recent Rust releases and thus it should generally work out
+of the box, e.g.::
 
 	USE='rust-src rustfmt clippy' emerge dev-lang/rust dev-util/bindgen
 
-- 
2.53.0

[PATCH v2 27/33] docs: rust: quick-start: remove Nix "unstable channel" note

[Miguel Ojeda]

Nix does not need the "unstable channel" note, since its packages are
recent enough even in the stable channel [1][2].

Thus remove it to simplify the documentation.

Link: https://search.nixos.org/packages?channel=25.11&query=rust [1]
Link: https://search.nixos.org/packages?channel=25.11&query=bindgen [2]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 1518367324fe..5bbe059a8fa3 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -68,8 +68,8 @@ of the box, e.g.::
 Nix
 ***
 
-Nix (unstable channel) provides recent Rust releases and thus it should
-generally work out of the box, e.g.::
+Nix provides recent Rust releases and thus it should generally work out of the
+box, e.g.::
 
 	{ pkgs ? import <nixpkgs> {} }:
 	pkgs.mkShell {
-- 
2.53.0

[PATCH v2 28/33] docs: rust: quick-start: remove GDB/Binutils mention

[Miguel Ojeda]

The versions provided nowadays by even a distribution like Debian Stable
(and Debian Old Stable) are newer than those mentioned [1].

Thus remove the workaround.

Note that the minimum binutils version in the kernel is still 2.30, so
one could argue part of the note is still relevant, but it is unlikely
a kernel developer using such an old binutils is enabling Rust on a
modern kernel, especially when using distribution toolchains, e.g. the
Rust minimum version is not satisfied by Debian Old Stable.

So we are at the point where keeping the docs short and relevant for
essentially everyone is probably the better trade-off.

Link: https://packages.debian.org/search?suite=all&searchon=names&keywords=binutils [1]
Link: https://lore.kernel.org/all/CANiq72mCpc9=2TN_zC4NeDMpFQtPXAFvyiP+gRApg2vzspPWmw@mail.gmail.com/
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/quick-start.rst | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 5bbe059a8fa3..a6ec3fa94d33 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -352,12 +352,3 @@ Hacking
 To dive deeper, take a look at the source code of the samples
 at ``samples/rust/``, the Rust support code under ``rust/`` and
 the ``Rust hacking`` menu under ``Kernel hacking``.
-
-If GDB/Binutils is used and Rust symbols are not getting demangled, the reason
-is the toolchain does not support Rust's new v0 mangling scheme yet.
-There are a few ways out:
-
-- Install a newer release (GDB >= 10.2, Binutils >= 2.36).
-
-- Some versions of GDB (e.g. vanilla GDB 10.1) are able to use
-  the pre-demangled names embedded in the debug info (``CONFIG_DEBUG_INFO``).
-- 
2.53.0

[PATCH v2 29/33] docs: rust: general-information: simplify Kconfig example

[Miguel Ojeda]

There is no need to use `def_bool y if <expr>` -- one can simply write
`def_bool <expr>`.

In fact, the simpler form is how we actually use them in practice in
`init/Kconfig`.

Thus simplify the example.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/general-information.rst | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/rust/general-information.rst b/Documentation/rust/general-information.rst
index 6146b49b6a98..91535b2306ed 100644
--- a/Documentation/rust/general-information.rst
+++ b/Documentation/rust/general-information.rst
@@ -158,4 +158,4 @@ numerical comparisons, one may define a new Kconfig symbol:
 .. code-block:: kconfig
 
 	config RUSTC_VERSION_MIN_107900
-		def_bool y if RUSTC_VERSION >= 107900
+		def_bool RUSTC_VERSION >= 107900
-- 
2.53.0

[PATCH v2 30/33] docs: rust: general-information: use real example

[Miguel Ojeda]

Currently the example in the documentation shows a version-based name
for the Kconfig example:

    RUSTC_VERSION_MIN_107900

The reason behind it was to possibly avoid repetition in case several
features used the same minimum.

However, we ended up preferring to give them a descriptive name for each
feature added even if that could lead to some repetition. In practice,
the repetition has not happened so far, and even if it does at some point,
it is not a big deal.

Thus replace the example in the documentation with one of our current
examples (after removing previous ones from the bump), to show how they
actually look like, and in case someone `grep`s for it.

In addition, it has the advantage that it shows the `RUSTC_HAS_*`
pattern we follow in `init/Kconfig`, similar to the C side.

Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Documentation/rust/general-information.rst | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Documentation/rust/general-information.rst b/Documentation/rust/general-information.rst
index 91535b2306ed..09234bed272c 100644
--- a/Documentation/rust/general-information.rst
+++ b/Documentation/rust/general-information.rst
@@ -157,5 +157,5 @@ numerical comparisons, one may define a new Kconfig symbol:
 
 .. code-block:: kconfig
 
-	config RUSTC_VERSION_MIN_107900
-		def_bool RUSTC_VERSION >= 107900
+	config RUSTC_HAS_SPAN_FILE
+		def_bool RUSTC_VERSION >= 108800
-- 
2.53.0

[PATCH v2 31/33] rust: declare cfi_encoding for lru_status

[Miguel Ojeda]

From: Alice Ryhl <aliceryhl@google.com>

By default bindgen will convert 'enum lru_status' into a typedef for an
integer. For the most part, an integer of the same size as the enum
results in the correct ABI, but in the specific case of CFI, that is not
the case. The CFI encoding is supposed to be the same as a struct called
'lru_status' rather than the name of the underlying native integer type.

To fix this, tell bindgen to generate a newtype and set the CFI type
explicitly. Note that we need to set the CFI attribute explicitly as
bindgen is using repr(transparent), which is otherwise identical to the
inner type for ABI purposes.

This allows us to remove the page range helper C function in Binder
without risking a CFI failure when list_lru_walk calls the provided
function pointer.

The --with-attribute-custom-enum argument requires bindgen v0.71 or
greater.

[ In particular, the feature was added in 0.71.0 [1][2].

  In addition, `feature(cfi_encoding)` has been available since
  Rust 1.71.0 [3].

  Link: https://github.com/rust-lang/rust-bindgen/issues/2520 [1]
  Link: https://github.com/rust-lang/rust-bindgen/pull/2866 [2]
  Link: https://github.com/rust-lang/rust/pull/105452 [3]

    - Miguel ]

My testing procedure was to add this to the android17-6.18 branch and
verify that rust_shrink_free_page is successfully called without crash,
and verify that it does in fact crash when the cfi_encoding is set to
other values. Note that I couldn't test this on android16-6.12 as that
branch uses a bindgen version that is too old.

Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260223-cfi-lru-status-v2-1-89c6448a63a4@google.com
Reviewed-by: Gary Guo <gary@garyguo.net>
[ Rebased on top of the minimum Rust version bump series which provide
  the required `bindgen` version. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 drivers/android/binder/Makefile            |  3 +--
 drivers/android/binder/page_range.rs       |  6 +++---
 drivers/android/binder/page_range_helper.c | 24 ----------------------
 drivers/android/binder/page_range_helper.h | 15 --------------
 rust/bindgen_parameters                    |  4 ++++
 rust/bindings/bindings_helper.h            |  1 -
 rust/bindings/lib.rs                       |  1 +
 rust/uapi/lib.rs                           |  1 +
 8 files changed, 10 insertions(+), 45 deletions(-)
 delete mode 100644 drivers/android/binder/page_range_helper.c
 delete mode 100644 drivers/android/binder/page_range_helper.h

diff --git a/drivers/android/binder/Makefile b/drivers/android/binder/Makefile
index 09eabb527fa0..7e0cd9782a8b 100644
--- a/drivers/android/binder/Makefile
+++ b/drivers/android/binder/Makefile
@@ -5,5 +5,4 @@ obj-$(CONFIG_ANDROID_BINDER_IPC_RUST) += rust_binder.o
 rust_binder-y := \
 	rust_binder_main.o	\
 	rust_binderfs.o		\
-	rust_binder_events.o	\
-	page_range_helper.o
+	rust_binder_events.o
diff --git a/drivers/android/binder/page_range.rs b/drivers/android/binder/page_range.rs
index fdd97112ef5c..8e9f5c4819d0 100644
--- a/drivers/android/binder/page_range.rs
+++ b/drivers/android/binder/page_range.rs
@@ -642,15 +642,15 @@ fn drop(self: Pin<&mut Self>) {
     unsafe {
         bindings::list_lru_walk(
             list_lru,
-            Some(bindings::rust_shrink_free_page_wrap),
+            Some(rust_shrink_free_page),
             ptr::null_mut(),
             nr_to_scan,
         )
     }
 }
 
-const LRU_SKIP: bindings::lru_status = bindings::lru_status_LRU_SKIP;
-const LRU_REMOVED_ENTRY: bindings::lru_status = bindings::lru_status_LRU_REMOVED_RETRY;
+const LRU_SKIP: bindings::lru_status = bindings::lru_status::LRU_SKIP;
+const LRU_REMOVED_ENTRY: bindings::lru_status = bindings::lru_status::LRU_REMOVED_RETRY;
 
 /// # Safety
 /// Called by the shrinker.
diff --git a/drivers/android/binder/page_range_helper.c b/drivers/android/binder/page_range_helper.c
deleted file mode 100644
index 496887723ee0..000000000000
--- a/drivers/android/binder/page_range_helper.c
+++ /dev/null
@@ -1,24 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-
-/* C helper for page_range.rs to work around a CFI violation.
- *
- * Bindgen currently pretends that `enum lru_status` is the same as an integer.
- * This assumption is fine ABI-wise, but once you add CFI to the mix, it
- * triggers a CFI violation because `enum lru_status` gets a different CFI tag.
- *
- * This file contains a workaround until bindgen can be fixed.
- *
- * Copyright (C) 2025 Google LLC.
- */
-#include "page_range_helper.h"
-
-unsigned int rust_shrink_free_page(struct list_head *item,
-				   struct list_lru_one *list,
-				   void *cb_arg);
-
-enum lru_status
-rust_shrink_free_page_wrap(struct list_head *item, struct list_lru_one *list,
-			   void *cb_arg)
-{
-	return rust_shrink_free_page(item, list, cb_arg);
-}
diff --git a/drivers/android/binder/page_range_helper.h b/drivers/android/binder/page_range_helper.h
deleted file mode 100644
index 18dd2dd117b2..000000000000
--- a/drivers/android/binder/page_range_helper.h
+++ /dev/null
@@ -1,15 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2025 Google, Inc.
- */
-
-#ifndef _LINUX_PAGE_RANGE_HELPER_H
-#define _LINUX_PAGE_RANGE_HELPER_H
-
-#include <linux/list_lru.h>
-
-enum lru_status
-rust_shrink_free_page_wrap(struct list_head *item, struct list_lru_one *list,
-			   void *cb_arg);
-
-#endif /* _LINUX_PAGE_RANGE_HELPER_H */
diff --git a/rust/bindgen_parameters b/rust/bindgen_parameters
index 112ec197ef0a..6f02d9720ad2 100644
--- a/rust/bindgen_parameters
+++ b/rust/bindgen_parameters
@@ -19,6 +19,10 @@
 # warning. We don't need to peek into it anyway.
 --opaque-type spinlock
 
+# enums that appear in indirect function calls should specify a cfi type
+--newtype-enum lru_status
+--with-attribute-custom-enum=lru_status='#[cfi_encoding="10lru_status"]'
+
 # `seccomp`'s comment gets understood as a doctest
 --no-doc-comments
 
diff --git a/rust/bindings/bindings_helper.h b/rust/bindings/bindings_helper.h
index 083cc44aa952..faf3ee634ced 100644
--- a/rust/bindings/bindings_helper.h
+++ b/rust/bindings/bindings_helper.h
@@ -149,5 +149,4 @@ const vm_flags_t RUST_CONST_HELPER_VM_NOHUGEPAGE = VM_NOHUGEPAGE;
 #if IS_ENABLED(CONFIG_ANDROID_BINDER_IPC_RUST)
 #include "../../drivers/android/binder/rust_binder.h"
 #include "../../drivers/android/binder/rust_binder_events.h"
-#include "../../drivers/android/binder/page_range_helper.h"
 #endif
diff --git a/rust/bindings/lib.rs b/rust/bindings/lib.rs
index e18c160dad17..854e7c471434 100644
--- a/rust/bindings/lib.rs
+++ b/rust/bindings/lib.rs
@@ -19,6 +19,7 @@
     unreachable_pub,
     unsafe_op_in_unsafe_fn
 )]
+#![feature(cfi_encoding)]
 
 #[allow(dead_code)]
 #[allow(clippy::cast_lossless)]
diff --git a/rust/uapi/lib.rs b/rust/uapi/lib.rs
index 821e286e0daa..b8a515de31ca 100644
--- a/rust/uapi/lib.rs
+++ b/rust/uapi/lib.rs
@@ -24,6 +24,7 @@
     unsafe_op_in_unsafe_fn
 )]
 #![cfg_attr(CONFIG_RUSTC_HAS_UNNECESSARY_TRANSMUTES, allow(unnecessary_transmutes))]
+#![feature(cfi_encoding)]
 
 // Manual definition of blocklisted types.
 type __kernel_size_t = usize;
-- 
2.53.0

[PATCH v2 32/33] rust: kbuild: support global per-version flags

[Miguel Ojeda]

Sometimes it is useful to gate global Rust flags per compiler version.
For instance, we may want to disable a lint that has false positives in
a single version [1].

We already had helpers like `rustc-min-version` for that, which we use
elsewhere, but we cannot currently use them for `rust_common_flags`,
which contains the global flags for all Rust code (kernel and host),
because `rustc-min-version` depends on `CONFIG_RUSTC_VERSION`, which
does not exist when `rust_common_flags` is defined.

Thus, to support that, introduce `rust_common_flags_per_version`,
defined after the `include/config/auto.conf` inclusion (where
`CONFIG_RUSTC_VERSION` becomes available), and append it to
`rust_common_flags`, `KBUILD_HOSTRUSTFLAGS` and `KBUILD_RUSTFLAGS`.

In addition, move the expansion of `HOSTRUSTFLAGS` to the same place,
so that users can also override per-version flags [2].

Link: https://lore.kernel.org/rust-for-linux/CANiq72mWdFU11GcCZRchzhy0Gi1QZShvZtyRkHV2O+WA2uTdVQ@mail.gmail.com/ [1]
Link: https://lore.kernel.org/rust-for-linux/CANiq72mTaA2tjhkLKf0-2hrrrt9rxWPgy6SfNSbponbGOegQvA@mail.gmail.com/ [2]
Link: https://patch.msgid.link/20260307170929.153892-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Makefile | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index 78f5ee173eda..a305ae4be522 100644
--- a/Makefile
+++ b/Makefile
@@ -506,7 +506,7 @@ KBUILD_HOSTCFLAGS   := $(KBUILD_USERHOSTCFLAGS) $(HOST_LFS_CFLAGS) \
 KBUILD_HOSTCXXFLAGS := -Wall -O2 $(HOST_LFS_CFLAGS) $(HOSTCXXFLAGS) \
 		       -I $(srctree)/scripts/include
 KBUILD_HOSTRUSTFLAGS := $(rust_common_flags) -O -Cstrip=debuginfo \
-			-Zallow-features= $(HOSTRUSTFLAGS)
+			-Zallow-features=
 KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 KBUILD_PROCMACROLDFLAGS := $(or $(PROCMACROLDFLAGS),$(KBUILD_HOSTLDFLAGS))
@@ -836,6 +836,14 @@ endif # CONFIG_TRACEPOINTS
 
 export WARN_ON_UNUSED_TRACEPOINTS
 
+# Per-version Rust flags. These are like `rust_common_flags`, but may
+# depend on the Rust compiler version (e.g. using `rustc-min-version`).
+rust_common_flags_per_version :=
+
+rust_common_flags += $(rust_common_flags_per_version)
+KBUILD_HOSTRUSTFLAGS += $(rust_common_flags_per_version) $(HOSTRUSTFLAGS)
+KBUILD_RUSTFLAGS += $(rust_common_flags_per_version)
+
 include $(srctree)/arch/$(SRCARCH)/Makefile
 
 ifdef need-config
-- 
2.53.0

[PATCH v2 33/33] rust: kbuild: allow `clippy::precedence` for Rust < 1.86.0

[Miguel Ojeda]

The Clippy `precedence` lint was extended in Rust 1.85.0 to include
bitmasking and shift operations [1]. However, because it generated
many hits, in Rust 1.86.0 it was split into a new `precedence_bits`
lint which is not enabled by default [2].

In other words, only Rust 1.85 has a different behavior. For instance,
it reports:

    warning: operator precedence can trip the unwary
      --> drivers/gpu/nova-core/fb/hal/ga100.rs:16:5
       |
    16 | /     u64::from(regs::NV_PFB_NISO_FLUSH_SYSMEM_ADDR::read(bar).adr_39_08()) << FLUSH_SYSMEM_ADDR_SHIFT
    17 | |         | u64::from(regs::NV_PFB_NISO_FLUSH_SYSMEM_ADDR_HI::read(bar).adr_63_40())
    18 | |             << FLUSH_SYSMEM_ADDR_SHIFT_HI
       | |_________________________________________^
       |
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#precedence
       = note: `-W clippy::precedence` implied by `-W clippy::all`
       = help: to override `-W clippy::all` add `#[allow(clippy::precedence)]`
    help: consider parenthesizing your expression
       |
    16 ~     (u64::from(regs::NV_PFB_NISO_FLUSH_SYSMEM_ADDR::read(bar).adr_39_08()) << FLUSH_SYSMEM_ADDR_SHIFT) | (u64::from(regs::NV_PFB_NISO_FLUSH_SYSMEM_ADDR_HI::read(bar).adr_63_40())
    17 +             << FLUSH_SYSMEM_ADDR_SHIFT_HI)
       |

While so far we try our best to keep all versions Clippy-clean, the
minimum (which is now Rust 1.85.0 after the bump) and the latest stable
are the most important ones; and this may be considered a "false positive"
with respect to the behavior in other versions.

Thus allow this lint for this version using the per-version flags
mechanism introduced in the previous commit.

Link: https://github.com/rust-lang/rust-clippy/issues/14097 [1]
Link: https://github.com/rust-lang/rust-clippy/pull/14115 [2]
Link: https://lore.kernel.org/rust-for-linux/DFVDKMMA7KPC.2DN0951H3H55Y@kernel.org/
Reviewed-by: Tamir Duberstein <tamird@kernel.org>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 Makefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index a305ae4be522..b8c38aa49cf4 100644
--- a/Makefile
+++ b/Makefile
@@ -838,7 +838,8 @@ export WARN_ON_UNUSED_TRACEPOINTS
 
 # Per-version Rust flags. These are like `rust_common_flags`, but may
 # depend on the Rust compiler version (e.g. using `rustc-min-version`).
-rust_common_flags_per_version :=
+rust_common_flags_per_version := \
+    $(if $(call rustc-min-version,108600),,-Aclippy::precedence)
 
 rust_common_flags += $(rust_common_flags_per_version)
 KBUILD_HOSTRUSTFLAGS += $(rust_common_flags_per_version) $(HOSTRUSTFLAGS)
-- 
2.53.0

Re: [PATCH v2 01/33] rust: kbuild: remove `--remap-path-prefix` workarounds

[Gary Guo]

On Mon Apr 6, 2026 at 12:52 AM BST, Miguel Ojeda wrote:
> Commit 8cf5b3f83614 ("Revert "kbuild, rust: use -fremap-path-prefix
> to make paths relative"") removed `--remap-path-prefix` from the build
> system, so the workarounds are not needed anymore.
> 
> Thus remove them.
> 
> Note that the flag has landed again in parallel in this cycle in
> commit dda135077ecc ("rust: build: remap path to avoid absolute path"),
> together with `--remap-path-scope=macro` [1]. However, they are gated on
> `rustc-option-yn, --remap-path-scope=macro`, which means they are both
> only passed starting with Rust 1.95.0 [2]:
> 
>   `--remap-path-scope` is only stable in Rust 1.95, so use `rustc-option`
>   to detect its presence. This feature has been available as
>   `-Zremap-path-scope` for all versions that we support; however due to
>   bugs in the Rust compiler, it does not work reliably until 1.94. I opted
>   to not enable it for 1.94 as it's just a single version that we missed.
> 
> In turn, that means the workarounds removed here should not be needed
> again (even with the flag added again above), since:
> 
>   - `rustdoc` now recognizes the `--remap-path-prefix` flag since Rust
>     1.81.0 [3] (even if it is still an unstable feature [4]).
> 
>   - The Internal Compiler Error [5] that the comment mentions was fixed in
>     Rust 1.87.0 [6]. We tested that was the case in a previous version
>     of this series by making the workaround conditional [7][8].
> 
> ...which are both older versions than Rust 1.95.0.
> 
> We will still need to skip `--remap-path-scope` for `rustdoc` though,
> since `rustdoc` does not support that one yet [4].
> 
> Link: https://github.com/rust-lang/rust/issues/111540 [1]
> Link: https://github.com/rust-lang/rust/pull/147611 [2]
> Link: https://github.com/rust-lang/rust/pull/107099 [3]
> Link: https://doc.rust-lang.org/nightly/rustdoc/unstable-features.html#--remap-path-prefix-remap-source-code-paths-in-output [4]
> Link: https://github.com/rust-lang/rust/issues/138520 [5]
> Link: https://github.com/rust-lang/rust/pull/138556 [6]
> Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-9-ojeda@kernel.org/ [7]
> Link: https://lore.kernel.org/rust-for-linux/20260401114540.30108-10-ojeda@kernel.org/ [8]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Acked-by: Gary Guo <gary@garyguo.net>

> ---
>  rust/Makefile | 8 ++------
>  1 file changed, 2 insertions(+), 6 deletions(-)

Re: [PATCH v2 07/33] rust: allow globally `clippy::incompatible_msrv`

[Gary Guo]

On Mon Apr 6, 2026 at 12:52 AM BST, Miguel Ojeda wrote:
> `clippy::incompatible_msrv` is not buying us much, and we discussed
> allowing it several times in the past.
> 
> For instance, there was recently another patch sent to `allow` it where
> needed [1]. While that particular case would not be needed after the
> minimum version bump to 1.85.0, it is simpler to just allow it to prevent
> future instances.
> 
> Thus do so, and remove the last instance of locally allowing it we have
> in the tree (except the one in the vendored `proc_macro2` crate).
> 
> Note that we still keep the `msrv` config option in `clippy.toml` since
> that affects other lints as well.
> 
> Link: https://lore.kernel.org/rust-for-linux/20260404212831.78971-4-jhubbard@nvidia.com/ [1]
> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Reviewed-by: Gary Guo <gary@garyguo.net>

> ---
>  Makefile               | 1 +
>  rust/macros/helpers.rs | 1 -
>  2 files changed, 1 insertion(+), 1 deletion(-)

Re: [PATCH v2 00/33] rust: bump minimum Rust and `bindgen` versions

[Miguel Ojeda]

On Mon, Apr 6, 2026 at 1:53 AM Miguel Ojeda <ojeda@kernel.org> wrote:
>
> As proposed in the past in e.g. LPC 2025 and the Maintainers Summit [1],
> we are going to follow Debian Stable's Rust versions as our minimum
> supported version.
>
> Debian Trixie was released with a Rust 1.85.0 toolchain [2], which it
> still uses to this day [3] (i.e. no update to Rust 1.85.1).
>
> Debian Trixie was released with `bindgen` 0.71.1, which it also still
> uses to this day [4].
>
> Debian Trixie's release happened on 2025-08-09 [5], which means that a
> fair amount of time has passed since its release for kernel developers
> to upgrade.
>
> Thus bump the minimum to the new versions, i.e.
>
>   - Rust: 1.78.0 -> 1.85.0
>   - bindgen: 0.65.1 -> 0.71.1
>
> There are a few main parts to the series, in this order:
>
>   - A few cleanups that can be performed before the bumps.
>   - The Rust bump (and its cleanups).
>   - The `bindgen` bump (and its cleanups).
>   - Documentation updates.
>   - The `cfi_encoding` patch, added here, which needs the bump.
>   - The per-version flags support and a Clippy cleanup on top.
>
> Link: https://lwn.net/Articles/1050174/ [1]
> Link: https://www.debian.org/releases/trixie/release-notes/whats-new.en.html#desktops-and-well-known-packages [2]
> Link: https://packages.debian.org/trixie/rustc [3]
> Link: https://packages.debian.org/trixie/bindgen [4]
> Link: https://www.debian.org/releases/trixie/ [5]

Applied series to `rust-next` -- thanks everyone!

Let's see if we find any issue in -next.

(If someone wants to give tags today, then I am happy to pick them up)

Cheers,
Miguel

Re: [PATCH v2 01/33] rust: kbuild: remove `--remap-path-prefix` workarounds

[Tamir Duberstein]

On Mon, 06 Apr 2026 01:52:37 +0200, Miguel Ojeda <ojeda@kernel.org> wrote:
> Commit 8cf5b3f83614 ("Revert "kbuild, rust: use -fremap-path-prefix
> to make paths relative"") removed `--remap-path-prefix` from the build
> system, so the workarounds are not needed anymore.
> 
> Thus remove them.
> 
> Note that the flag has landed again in parallel in this cycle in
> commit dda135077ecc ("rust: build: remap path to avoid absolute path"),
> together with `--remap-path-scope=macro` [1]. However, they are gated on
> `rustc-option-yn, --remap-path-scope=macro`, which means they are both
> only passed starting with Rust 1.95.0 [2]:
> 
> [...]

Reviewed-by: Tamir Duberstein <tamird@kernel.org>

-- 
Tamir Duberstein <tamird@kernel.org>

Re: [PATCH v2 07/33] rust: allow globally `clippy::incompatible_msrv`

[Tamir Duberstein]

On Mon, 06 Apr 2026 01:52:43 +0200, Miguel Ojeda <ojeda@kernel.org> wrote:
> diff --git a/Makefile b/Makefile
> index a63684c36d60..78f5ee173eda 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -486,6 +486,7 @@ export rust_common_flags := --edition=2021 \
>  			    -Wclippy::as_underscore \
>  			    -Wclippy::cast_lossless \
>  			    -Wclippy::ignored_unit_patterns \
> +			    -Aclippy::incompatible_msrv \

Could you add a reference to the upstream bug report [0] here?

Link: https://github.com/rust-lang/rust-clippy/issues/14425 [0]
Reviewed-by: Tamir Duberstein <tamird@kernel.org>

-- 
Tamir Duberstein <tamird@kernel.org>

Re: [PATCH v2 15/33] rust: macros: simplify code using `feature(extract_if)`

[Tamir Duberstein]

On Mon, 06 Apr 2026 01:52:51 +0200, Miguel Ojeda <ojeda@kernel.org> wrote:
> `feature(extract_if)` [1] was stabilized in Rust 1.87.0 [2], and the last
> significant change happened in Rust 1.85.0 [3] when the range parameter
> was added.
> 
> That is, with our new minimum version, we can start using the feature.
> 
> Thus simplify the code using the feature and remove the TODO comment.
> 
> [...]

Reviewed-by: Tamir Duberstein <tamird@kernel.org>

-- 
Tamir Duberstein <tamird@kernel.org>

Re: [PATCH v2 32/33] rust: kbuild: support global per-version flags

[Tamir Duberstein]

On Mon, 06 Apr 2026 01:53:08 +0200, Miguel Ojeda <ojeda@kernel.org> wrote:
> Sometimes it is useful to gate global Rust flags per compiler version.
> For instance, we may want to disable a lint that has false positives in
> a single version [1].
> 
> We already had helpers like `rustc-min-version` for that, which we use
> elsewhere, but we cannot currently use them for `rust_common_flags`,
> which contains the global flags for all Rust code (kernel and host),
> because `rustc-min-version` depends on `CONFIG_RUSTC_VERSION`, which
> does not exist when `rust_common_flags` is defined.
> 
> [...]

Reviewed-by: Tamir Duberstein <tamird@kernel.org>

-- 
Tamir Duberstein <tamird@kernel.org>

Re: [PATCH v2 07/33] rust: allow globally `clippy::incompatible_msrv`

[Miguel Ojeda]

On Mon, Apr 6, 2026 at 4:29 PM Tamir Duberstein <tamird@kernel.org> wrote:
>
> Could you add a reference to the upstream bug report [0] here?

Of course, thanks for the tags!

Cheers,
Miguel

Re: [PATCH v2 07/33] rust: allow globally `clippy::incompatible_msrv`

[Tamir Duberstein]

On Mon, Apr 6, 2026 at 10:38 AM Miguel Ojeda
<miguel.ojeda.sandonis@gmail.com> wrote:
>
> On Mon, Apr 6, 2026 at 4:29 PM Tamir Duberstein <tamird@kernel.org> wrote:
> >
> > Could you add a reference to the upstream bug report [0] here?
>
> Of course, thanks for the tags!

You're welcome! Actually it seems the lint was already improved
upstream, starting with 1.90.0.

Link: https://github.com/rust-lang/rust-clippy/commit/c0dc3b61 [0]

Re: [PATCH v2 00/33] rust: bump minimum Rust and `bindgen` versions

[John Hubbard]

On 4/6/26 2:03 AM, Miguel Ojeda wrote:
> On Mon, Apr 6, 2026 at 1:53 AM Miguel Ojeda <ojeda@kernel.org> wrote:
... 
> Applied series to `rust-next` -- thanks everyone!
> 
> Let's see if we find any issue in -next.
> 

Looks good from the perspective of this patchset. I am seeing
one remaining problem that we previously came up with a fix for,
so I expect that that fix is staged in another branch. But in
case it's not, here is the report:

On today's rust-next, using rustc 1.85.0, at commit 232e79c72f57
("rust: kbuild: allow `clippy::precedence` for Rust < 1.86.0"):

  CLIPPY [M] drivers/gpu/drm/nova/nova.o
warning: consider removing unnecessary double parentheses
    --> rust/doctests_kernel_generated.rs:4240:14
     |
4240 |     pr_info!("The policy details are: {:?}\n", (policy.cpu(), policy.cur()));
     |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
     |
     = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#double_parens
     = note: `-W clippy::double-parens` implied by `-W clippy::all`
     = help: to override `-W clippy::all` add `#[allow(clippy::double_parens)]`

warning: 1 warning emitted



thanks,
-- 
John Hubbard

Re: [PATCH v2 00/33] rust: bump minimum Rust and `bindgen` versions

[Miguel Ojeda]

On Mon, Apr 6, 2026 at 8:51 PM John Hubbard <jhubbard@nvidia.com> wrote:
>
> Looks good from the perspective of this patchset. I am seeing
> one remaining problem that we previously came up with a fix for,
> so I expect that that fix is staged in another branch. But in
> case it's not, here is the report:
>
> On today's rust-next, using rustc 1.85.0, at commit 232e79c72f57
> ("rust: kbuild: allow `clippy::precedence` for Rust < 1.86.0"):
>
>   CLIPPY [M] drivers/gpu/drm/nova/nova.o
> warning: consider removing unnecessary double parentheses
>     --> rust/doctests_kernel_generated.rs:4240:14
>      |
> 4240 |     pr_info!("The policy details are: {:?}\n", (policy.cpu(), policy.cur()));
>      |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>      |
>      = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#double_parens
>      = note: `-W clippy::double-parens` implied by `-W clippy::all`
>      = help: to override `-W clippy::all` add `#[allow(clippy::double_parens)]`
>
> warning: 1 warning emitted

That is already fixed and in mainline: 487f9b3dc6e5 ("rust: cpufreq:
suppress clippy::double_parens in Policy doctest").

Cheers,
Miguel

Re: [PATCH v2 00/33] rust: bump minimum Rust and `bindgen` versions

[John Hubbard]

On 4/6/26 12:01 PM, Miguel Ojeda wrote:
> On Mon, Apr 6, 2026 at 8:51 PM John Hubbard <jhubbard@nvidia.com> wrote:
>>
>> Looks good from the perspective of this patchset. I am seeing
>> one remaining problem that we previously came up with a fix for,
>> so I expect that that fix is staged in another branch. But in
>> case it's not, here is the report:
>>
>> On today's rust-next, using rustc 1.85.0, at commit 232e79c72f57
>> ("rust: kbuild: allow `clippy::precedence` for Rust < 1.86.0"):
>>
>>   CLIPPY [M] drivers/gpu/drm/nova/nova.o
>> warning: consider removing unnecessary double parentheses
>>     --> rust/doctests_kernel_generated.rs:4240:14
>>      |
>> 4240 |     pr_info!("The policy details are: {:?}\n", (policy.cpu(), policy.cur()));
>>      |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>>      |
>>      = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#double_parens
>>      = note: `-W clippy::double-parens` implied by `-W clippy::all`
>>      = help: to override `-W clippy::all` add `#[allow(clippy::double_parens)]`
>>
>> warning: 1 warning emitted
> 
> That is already fixed and in mainline: 487f9b3dc6e5 ("rust: cpufreq:
> suppress clippy::double_parens in Policy doctest").
> 

That's what I thought I recalled, too. Weird that it is not in rust-next
already, though.


thanks,
-- 
John Hubbard