Re: [PATCH] rust: macros: Fix macro referencing core and kernel crates

Re: [PATCH] rust: macros: Fix macro referencing core and kernel crates

[Benno Lossin]

On Wed Mar 26, 2025 at 7:23 PM CET, Igor Korotin wrote:
> To prevent issues where user-defined modules named `core` or `kernel`
> could be picked up instead of the standard ones, update macros to use
> absolute paths, `::core::...` and `::kernel::...`, for core and kernel
> references.

Please split this sentence up into smaller parts. Also "standard ones"
sounds weird to me, `core` and `kernel` are crates and not modules.

> Suggested-by: y86-dev <y86-dev@protonmail.com>

Please use my real name and other mail address instead:
    
    Benno Lossin <benno.lossin@proton.me>

> Closes: https://github.com/Rust-for-Linux/linux/issues/1150
> Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
> ---
>  rust/ffi.rs                  | 2 +-
>  rust/kernel/device.rs        | 2 +-
>  rust/kernel/device_id.rs     | 4 ++--
>  rust/kernel/kunit.rs         | 8 ++++----
>  rust/kernel/static_assert.rs | 4 ++--
>  rust/kernel/str.rs           | 4 ++--
>  rust/macros/lib.rs           | 6 +++---
>  scripts/rustdoc_test_gen.rs  | 8 ++++++--
>  8 files changed, 21 insertions(+), 17 deletions(-)

There are also some occurrences of `kernel::` & `core::` in proc macros,
for example:
- rust/macros/kunit.rs:129
- rust/macros/module.rs:347
- ...

Could you also add those to the patch? Thanks!

(line numbers after applying your patch to rust-next)

---
Cheers,
Benno

[PATCH v2 0/1] rust: macros: Fix macro referencing core and kernel crates v2

[Igor Korotin]

> > To prevent issues where user-defined modules named `core` or `kernel`
> > could be picked up instead of the standard ones, update macros to use
> > absolute paths, `::core::...` and `::kernel::...`, for core and kernel
> > references.
> 
> Please split this sentence up into smaller parts. Also "standard ones"
> sounds weird to me, `core` and `kernel` are crates and not modules.

Simplified the commit message.

> > Suggested-by: y86-dev <y86-dev@protonmail.com>
> 
> Please use my real name and other mail address instead:
>    
>     Benno Lossin <benno.lossin@proton.me>

Sure. Tried to find your creds via your github profile/commits without 
success.

> > Closes: https://github.com/Rust-for-Linux/linux/issues/1150
> > Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
> > ---
> >  rust/ffi.rs                  | 2 +-
> >  rust/kernel/device.rs        | 2 +-
> >  rust/kernel/device_id.rs    | 4 ++--
> >  rust/kernel/kunit.rs        | 8 ++++----
> >  rust/kernel/static_assert.rs | 4 ++--
> >  rust/kernel/str.rs          | 4 ++--
> >  rust/macros/lib.rs          | 6 +++---
> >  scripts/rustdoc_test_gen.rs  | 8 ++++++--
> >  8 files changed, 21 insertions(+), 17 deletions(-)
> 
> There are also some occurrences of `kernel::` & `core::` in proc macros,
> for example:
> - rust/macros/kunit.rs:129
> - rust/macros/module.rs:347
> - ...
> 
> Could you also add those to the patch? Thanks!
> 
> (line numbers after applying your patch to rust-next)

Agreed. Fixed references in auto-generated code in files
1. rust/macros/kunit.rs            
2. rust/macros/module.rs           
3. scripts/rustdoc_test_builder.rs 
4. scripts/rustdoc_test_gen.rs     

-- 
2.43.0

[PATCH v2 1/1] rust: macros: Fix macro referencing core and kernel crates v2

[Igor Korotin]

Update macros to always use absolute paths for crates `core` and `kernel`.
This guarantees that macros will not pick up user-defined crates `core`
or `kernel` by accident.

Changes since v1:
- Fixed paths in auto-generated code.

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Closes: https://github.com/Rust-for-Linux/linux/issues/1150
Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
---
 rust/ffi.rs                     |  2 +-
 rust/kernel/device.rs           |  2 +-
 rust/kernel/device_id.rs        |  4 ++--
 rust/kernel/kunit.rs            |  8 ++++----
 rust/kernel/static_assert.rs    |  4 ++--
 rust/kernel/str.rs              |  4 ++--
 rust/macros/kunit.rs            | 22 +++++++++++-----------
 rust/macros/lib.rs              |  6 +++---
 rust/macros/module.rs           | 31 ++++++++++++++++---------------
 scripts/rustdoc_test_builder.rs |  6 +++---
 scripts/rustdoc_test_gen.rs     | 16 ++++++++++------
 11 files changed, 55 insertions(+), 50 deletions(-)

diff --git a/rust/ffi.rs b/rust/ffi.rs
index 584f75b49862..d60aad792af4 100644
--- a/rust/ffi.rs
+++ b/rust/ffi.rs
@@ -17,7 +17,7 @@ macro_rules! alias {
 
         // Check size compatibility with `core`.
         const _: () = assert!(
-            core::mem::size_of::<$name>() == core::mem::size_of::<core::ffi::$name>()
+            ::core::mem::size_of::<$name>() == ::core::mem::size_of::<::core::ffi::$name>()
         );
     )*}
 }
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index db2d9658ba47..2b19a8597158 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -214,7 +214,7 @@ unsafe impl Sync for Device {}
 macro_rules! dev_printk {
     ($method:ident, $dev:expr, $($f:tt)*) => {
         {
-            ($dev).$method(core::format_args!($($f)*));
+            ($dev).$method(::core::format_args!($($f)*));
         }
     }
 }
diff --git a/rust/kernel/device_id.rs b/rust/kernel/device_id.rs
index e5859217a579..0a4eb56d98f2 100644
--- a/rust/kernel/device_id.rs
+++ b/rust/kernel/device_id.rs
@@ -159,7 +159,7 @@ macro_rules! module_device_table {
                     "_", line!(),
                     "_", stringify!($table_name))
         ]
-        static $module_table_name: [core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
-            unsafe { core::mem::transmute_copy($table_name.raw_ids()) };
+        static $module_table_name: [::core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
+            unsafe { ::core::mem::transmute_copy($table_name.raw_ids()) };
     };
 }
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 1604fb6a5b1b..81833a687b75 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -59,7 +59,7 @@ macro_rules! kunit_assert {
             }
 
             static FILE: &'static $crate::str::CStr = $crate::c_str!($file);
-            static LINE: i32 = core::line!() as i32 - $diff;
+            static LINE: i32 = ::core::line!() as i32 - $diff;
             static CONDITION: &'static $crate::str::CStr = $crate::c_str!(stringify!($condition));
 
             // SAFETY: FFI call without safety requirements.
@@ -130,11 +130,11 @@ unsafe impl Sync for UnaryAssert {}
             unsafe {
                 $crate::bindings::__kunit_do_failed_assertion(
                     kunit_test,
-                    core::ptr::addr_of!(LOCATION.0),
+                    ::core::ptr::addr_of!(LOCATION.0),
                     $crate::bindings::kunit_assert_type_KUNIT_ASSERTION,
-                    core::ptr::addr_of!(ASSERTION.0.assert),
+                    ::core::ptr::addr_of!(ASSERTION.0.assert),
                     Some($crate::bindings::kunit_unary_assert_format),
-                    core::ptr::null(),
+                    ::core::ptr::null(),
                 );
             }
 
diff --git a/rust/kernel/static_assert.rs b/rust/kernel/static_assert.rs
index 3115ee0ba8e9..f3f8c6eb7360 100644
--- a/rust/kernel/static_assert.rs
+++ b/rust/kernel/static_assert.rs
@@ -16,7 +16,7 @@
 ///
 /// ```
 /// static_assert!(42 > 24);
-/// static_assert!(core::mem::size_of::<u8>() == 1);
+/// static_assert!(::core::mem::size_of::<u8>() == 1);
 ///
 /// const X: &[u8] = b"bar";
 /// static_assert!(X[1] == b'a');
@@ -29,6 +29,6 @@
 #[macro_export]
 macro_rules! static_assert {
     ($condition:expr) => {
-        const _: () = core::assert!($condition);
+        const _: () = ::core::assert!($condition);
     };
 }
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 878111cb77bc..aed7b2617c32 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -595,7 +595,7 @@ fn deref(&self) -> &str {
 
     macro_rules! format {
         ($($f:tt)*) => ({
-            &*String::from_fmt(kernel::fmt!($($f)*))
+            &*String::from_fmt(::kernel::fmt!($($f)*))
         })
     }
 
@@ -944,5 +944,5 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 /// A convenience alias for [`core::format_args`].
 #[macro_export]
 macro_rules! fmt {
-    ($($f:tt)*) => ( core::format_args!($($f)*) )
+    ($($f:tt)*) => ( ::core::format_args!($($f)*) )
 }
diff --git a/rust/macros/kunit.rs b/rust/macros/kunit.rs
index 4f553ecf40c0..61fc25228e72 100644
--- a/rust/macros/kunit.rs
+++ b/rust/macros/kunit.rs
@@ -88,29 +88,29 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream {
     // Looks like:
     //
     // ```
-    // unsafe extern "C" fn kunit_rust_wrapper_foo(_test: *mut kernel::bindings::kunit) { foo(); }
-    // unsafe extern "C" fn kunit_rust_wrapper_bar(_test: *mut kernel::bindings::kunit) { bar(); }
+    // unsafe extern "C" fn kunit_rust_wrapper_foo(_test: *mut ::kernel::bindings::kunit) { foo(); }
+    // unsafe extern "C" fn kunit_rust_wrapper_bar(_test: *mut ::kernel::bindings::kunit) { bar(); }
     //
-    // static mut TEST_CASES: [kernel::bindings::kunit_case; 3] = [
-    //     kernel::kunit::kunit_case(kernel::c_str!("foo"), kunit_rust_wrapper_foo),
-    //     kernel::kunit::kunit_case(kernel::c_str!("bar"), kunit_rust_wrapper_bar),
-    //     kernel::kunit::kunit_case_null(),
+    // static mut TEST_CASES: [::kernel::bindings::kunit_case; 3] = [
+    //     ::kernel::kunit::kunit_case(::kernel::c_str!("foo"), kunit_rust_wrapper_foo),
+    //     ::kernel::kunit::kunit_case(::kernel::c_str!("bar"), kunit_rust_wrapper_bar),
+    //     ::kernel::kunit::kunit_case_null(),
     // ];
     //
-    // kernel::kunit_unsafe_test_suite!(kunit_test_suit_name, TEST_CASES);
+    // ::kernel::kunit_unsafe_test_suite!(kunit_test_suit_name, TEST_CASES);
     // ```
     let mut kunit_macros = "".to_owned();
     let mut test_cases = "".to_owned();
     for test in &tests {
         let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{}", test);
         let kunit_wrapper = format!(
-            "unsafe extern \"C\" fn {}(_test: *mut kernel::bindings::kunit) {{ {}(); }}",
+            "unsafe extern \"C\" fn {}(_test: *mut ::kernel::bindings::kunit) {{ {}(); }}",
             kunit_wrapper_fn_name, test
         );
         writeln!(kunit_macros, "{kunit_wrapper}").unwrap();
         writeln!(
             test_cases,
-            "    kernel::kunit::kunit_case(kernel::c_str!(\"{}\"), {}),",
+            "    ::kernel::kunit::kunit_case(::kernel::c_str!(\"{}\"), {}),",
             test, kunit_wrapper_fn_name
         )
         .unwrap();
@@ -119,14 +119,14 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream {
     writeln!(kunit_macros).unwrap();
     writeln!(
         kunit_macros,
-        "static mut TEST_CASES: [kernel::bindings::kunit_case; {}] = [\n{test_cases}    kernel::kunit::kunit_case_null(),\n];",
+        "static mut TEST_CASES: [::kernel::bindings::kunit_case; {}] = [\n{test_cases}    ::kernel::kunit::kunit_case_null(),\n];",
         tests.len() + 1
     )
     .unwrap();
 
     writeln!(
         kunit_macros,
-        "kernel::kunit_unsafe_test_suite!({attr}, TEST_CASES);"
+        "::kernel::kunit_unsafe_test_suite!({attr}, TEST_CASES);"
     )
     .unwrap();
 
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index 9acaa68c974e..cb429eceff71 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -283,7 +283,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
 /// macro_rules! pub_no_prefix {
 ///     ($prefix:ident, $($newname:ident),+) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             $(pub(crate) const $newname: u32 = [<$prefix $newname>];)+
 ///         }
 ///     };
@@ -340,7 +340,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
 /// macro_rules! pub_no_prefix {
 ///     ($prefix:ident, $($newname:ident),+) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             $(pub(crate) const fn [<$newname:lower:span>]() -> u32 { [<$prefix $newname:span>] })+
 ///         }
 ///     };
@@ -375,7 +375,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// ```
 /// macro_rules! create_numbered_fn {
 ///     ($name:literal, $val:literal) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             fn [<some_ $name _fn $val>]() -> u32 { $val }
 ///         }
 ///     };
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index 8ab4e1f3eb45..615cefd4160a 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -224,20 +224,20 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
             // SAFETY: `__this_module` is constructed by the kernel at load time and will not be
             // freed until the module is unloaded.
             #[cfg(MODULE)]
-            static THIS_MODULE: kernel::ThisModule = unsafe {{
+            static THIS_MODULE: ::kernel::ThisModule = unsafe {{
                 extern \"C\" {{
-                    static __this_module: kernel::types::Opaque<kernel::bindings::module>;
+                    static __this_module: ::kernel::types::Opaque<::kernel::bindings::module>;
                 }}
 
-                kernel::ThisModule::from_ptr(__this_module.get())
+                ::kernel::ThisModule::from_ptr(__this_module.get())
             }};
             #[cfg(not(MODULE))]
-            static THIS_MODULE: kernel::ThisModule = unsafe {{
-                kernel::ThisModule::from_ptr(core::ptr::null_mut())
+            static THIS_MODULE: ::kernel::ThisModule = unsafe {{
+                ::kernel::ThisModule::from_ptr(::core::ptr::null_mut())
             }};
 
-            impl kernel::ModuleMetadata for {type_} {{
-                const NAME: &'static kernel::str::CStr = kernel::c_str!(\"{name}\");
+            impl ::kernel::ModuleMetadata for {type_} {{
+                const NAME: &'static ::kernel::str::CStr = ::kernel::c_str!(\"{name}\");
             }}
 
             // Double nested modules, since then nobody can access the public items inside.
@@ -255,8 +255,8 @@ mod __module_init {{
                     #[used]
                     static __IS_RUST_MODULE: () = ();
 
-                    static mut __MOD: core::mem::MaybeUninit<{type_}> =
-                        core::mem::MaybeUninit::uninit();
+                    static mut __MOD: ::core::mem::MaybeUninit<{type_}> =
+                        ::core::mem::MaybeUninit::uninit();
 
                     // Loadable modules need to export the `{{init,cleanup}}_module` identifiers.
                     /// # Safety
@@ -267,7 +267,7 @@ mod __module_init {{
                     #[doc(hidden)]
                     #[no_mangle]
                     #[link_section = \".init.text\"]
-                    pub unsafe extern \"C\" fn init_module() -> kernel::ffi::c_int {{
+                    pub unsafe extern \"C\" fn init_module() -> ::kernel::ffi::c_int {{
                         // SAFETY: This function is inaccessible to the outside due to the double
                         // module wrapping it. It is called exactly once by the C side via its
                         // unique name.
@@ -306,11 +306,12 @@ mod __module_init {{
                     #[doc(hidden)]
                     #[link_section = \"{initcall_section}\"]
                     #[used]
-                    pub static __{name}_initcall: extern \"C\" fn() -> kernel::ffi::c_int = __{name}_init;
+                    pub static __{name}_initcall: extern \"C\" fn() -> ::kernel::ffi::c_int =
+                        __{name}_init;
 
                     #[cfg(not(MODULE))]
                     #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)]
-                    core::arch::global_asm!(
+                    ::core::arch::global_asm!(
                         r#\".section \"{initcall_section}\", \"a\"
                         __{name}_initcall:
                             .long   __{name}_init - .
@@ -321,7 +322,7 @@ mod __module_init {{
                     #[cfg(not(MODULE))]
                     #[doc(hidden)]
                     #[no_mangle]
-                    pub extern \"C\" fn __{name}_init() -> kernel::ffi::c_int {{
+                    pub extern \"C\" fn __{name}_init() -> ::kernel::ffi::c_int {{
                         // SAFETY: This function is inaccessible to the outside due to the double
                         // module wrapping it. It is called exactly once by the C side via its
                         // placement above in the initcall section.
@@ -344,9 +345,9 @@ mod __module_init {{
                     /// # Safety
                     ///
                     /// This function must only be called once.
-                    unsafe fn __init() -> kernel::ffi::c_int {{
+                    unsafe fn __init() -> ::kernel::ffi::c_int {{
                         let initer =
-                            <{type_} as kernel::InPlaceModule>::init(&super::super::THIS_MODULE);
+                            <{type_} as ::kernel::InPlaceModule>::init(&super::super::THIS_MODULE);
                         // SAFETY: No data race, since `__MOD` can only be accessed by this module
                         // and there only `__init` and `__exit` access it. These functions are only
                         // called once and `__exit` cannot be called before or during `__init`.
diff --git a/scripts/rustdoc_test_builder.rs b/scripts/rustdoc_test_builder.rs
index e5894652f12c..81233fb56b66 100644
--- a/scripts/rustdoc_test_builder.rs
+++ b/scripts/rustdoc_test_builder.rs
@@ -28,7 +28,7 @@ fn main() {
     //
     // ```
     // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_28_0() {
-    // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_37_0() -> Result<(), impl core::fmt::Debug> {
+    // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_37_0() -> Result<(), impl ::core::fmt::Debug> {
     // ```
     //
     // It should be unlikely that doctest code matches such lines (when code is formatted properly).
@@ -49,8 +49,8 @@ fn main() {
 
     // Qualify `Result` to avoid the collision with our own `Result` coming from the prelude.
     let body = body.replace(
-        &format!("{rustdoc_function_name}() -> Result<(), impl core::fmt::Debug> {{"),
-        &format!("{rustdoc_function_name}() -> core::result::Result<(), impl core::fmt::Debug> {{"),
+        &format!("{rustdoc_function_name}() -> Result<(), impl ::core::fmt::Debug> {{"),
+        &format!("{rustdoc_function_name}() -> ::core::result::Result<(), impl ::core::fmt::Debug> {{"),
     );
 
     // For tests that get generated with `Result`, like above, `rustdoc` generates an `unwrap()` on
diff --git a/scripts/rustdoc_test_gen.rs b/scripts/rustdoc_test_gen.rs
index 036635fb1621..f8d053f75270 100644
--- a/scripts/rustdoc_test_gen.rs
+++ b/scripts/rustdoc_test_gen.rs
@@ -167,12 +167,14 @@ fn main() {
             rust_tests,
             r#"/// Generated `{name}` KUnit test case from a Rust documentation test.
 #[no_mangle]
-pub extern "C" fn {kunit_name}(__kunit_test: *mut kernel::bindings::kunit) {{
+pub extern "C" fn {kunit_name}(__kunit_test: *mut ::kernel::bindings::kunit) {{
     /// Overrides the usual [`assert!`] macro with one that calls KUnit instead.
     #[allow(unused)]
     macro_rules! assert {{
         ($cond:expr $(,)?) => {{{{
-            kernel::kunit_assert!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond);
+            ::kernel::kunit_assert!(
+                "{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond
+            );
         }}}}
     }}
 
@@ -180,13 +182,15 @@ macro_rules! assert {{
     #[allow(unused)]
     macro_rules! assert_eq {{
         ($left:expr, $right:expr $(,)?) => {{{{
-            kernel::kunit_assert_eq!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right);
+            ::kernel::kunit_assert_eq!(
+                "{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right
+            );
         }}}}
     }}
 
     // Many tests need the prelude, so provide it by default.
     #[allow(unused)]
-    use kernel::prelude::*;
+    use ::kernel::prelude::*;
 
     // Unconditionally print the location of the original doctest (i.e. rather than the location in
     // the generated file) so that developers can easily map the test back to the source code.
@@ -197,11 +201,11 @@ macro_rules! assert_eq {{
     // This follows the syntax for declaring test metadata in the proposed KTAP v2 spec, which may
     // be used for the proposed KUnit test attributes API. Thus hopefully this will make migration
     // easier later on.
-    kernel::kunit::info(format_args!("    # {kunit_name}.location: {real_path}:{line}\n"));
+    ::kernel::kunit::info(format_args!("    # {kunit_name}.location: {real_path}:{line}\n"));
 
     /// The anchor where the test code body starts.
     #[allow(unused)]
-    static __DOCTEST_ANCHOR: i32 = core::line!() as i32 + {body_offset} + 1;
+    static __DOCTEST_ANCHOR: i32 = ::core::line!() as i32 + {body_offset} + 1;
     {{
         {body}
         main();
-- 
2.43.0

Re: [PATCH v2 1/1] rust: macros: Fix macro referencing core and kernel crates v2

[Benno Lossin]

On Fri Mar 28, 2025 at 7:03 PM CET, Igor Korotin wrote:
> Update macros to always use absolute paths for crates `core` and `kernel`.
> This guarantees that macros will not pick up user-defined crates `core`
> or `kernel` by accident.

The crates are not user-defineable. Your initial message was correct in
that the user can define *modules* that have precedence over the crates
`core` and `kernel`.

> Changes since v1:
> - Fixed paths in auto-generated code.

The changelog shouldn't be in the commit message. Instead place it below
the `---`, but before the change stats.

> Suggested-by: Benno Lossin <benno.lossin@proton.me>
> Closes: https://github.com/Rust-for-Linux/linux/issues/1150
> Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
> ---

(put the changelog here)

---
Cheers,
Benno

>  rust/ffi.rs                     |  2 +-
>  rust/kernel/device.rs           |  2 +-
>  rust/kernel/device_id.rs        |  4 ++--
>  rust/kernel/kunit.rs            |  8 ++++----
>  rust/kernel/static_assert.rs    |  4 ++--
>  rust/kernel/str.rs              |  4 ++--
>  rust/macros/kunit.rs            | 22 +++++++++++-----------
>  rust/macros/lib.rs              |  6 +++---
>  rust/macros/module.rs           | 31 ++++++++++++++++---------------
>  scripts/rustdoc_test_builder.rs |  6 +++---
>  scripts/rustdoc_test_gen.rs     | 16 ++++++++++------
>  11 files changed, 55 insertions(+), 50 deletions(-)

[PATCH v3] rust: macros: Fix macro referencing core and kernel crates

[Igor Korotin]

Took into account all the remarks. Hope this letter with the patch covers
all of them. 

Thanks
Igor Korotin

Re: [PATCH v3] rust: macros: Fix macro referencing core and kernel crates

[Miguel Ojeda]

On Mon, Mar 31, 2025 at 12:46 PM Igor Korotin <igor.korotin@yahoo.com> wrote:
>
> Took into account all the remarks. Hope this letter with the patch covers
> all of them.

I think something went wrong here. You seem to be using `git
send-email`, but this doesn't look like it came out from `git
format-patch`.

By the way, it may be easier if you just send it as a new thread,
rather than replying to the previous version.

Thanks!

Cheers,
Miguel

[PATCH] rust: macros: Fix macro referencing core and kernel crates

[Igor Korotin]

Fix macros and auto-generated code to use absolute paths, `::core::...`
and `::kernel::...`, for core and kernel references. This prevents issues
where user-defined modules named `core` or `kernel` could be picked up
instead of the `core` or `kernel` crates.

Suggested-by: Benno Lossin <benno.lossin@proton.me>
Closes: https://github.com/Rust-for-Linux/linux/issues/1150
Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
---

Changes since v2:
 - rewrote commit message
 - link to v2: https://lore.kernel.org/lkml/20250328180312.2025317-2-igor.korotin@yahoo.com/
Changes since v1:
 - rewrote commit message
 - Added fixes in auto-generated code in files rust/macros/kunit.rs, 
   rust/macros/module.rs, scripts/rustdoc_test_builder.rs,
   scripts/rustdoc_test_gen.rs thanks to Benno
 - link to v1: https://lore.kernel.org/lkml/20250326182302.5650-1-igor.korotin@yahoo.com/

 rust/ffi.rs                     |  2 +-
 rust/kernel/device.rs           |  2 +-
 rust/kernel/device_id.rs        |  4 ++--
 rust/kernel/kunit.rs            |  8 ++++----
 rust/kernel/static_assert.rs    |  4 ++--
 rust/kernel/str.rs              |  4 ++--
 rust/macros/kunit.rs            | 22 +++++++++++-----------
 rust/macros/lib.rs              |  6 +++---
 rust/macros/module.rs           | 31 ++++++++++++++++---------------
 scripts/rustdoc_test_builder.rs |  9 ++++++---
 scripts/rustdoc_test_gen.rs     | 16 ++++++++++------
 11 files changed, 58 insertions(+), 50 deletions(-)

diff --git a/rust/ffi.rs b/rust/ffi.rs
index 584f75b49862..d60aad792af4 100644
--- a/rust/ffi.rs
+++ b/rust/ffi.rs
@@ -17,7 +17,7 @@ macro_rules! alias {
 
         // Check size compatibility with `core`.
         const _: () = assert!(
-            core::mem::size_of::<$name>() == core::mem::size_of::<core::ffi::$name>()
+            ::core::mem::size_of::<$name>() == ::core::mem::size_of::<::core::ffi::$name>()
         );
     )*}
 }
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index db2d9658ba47..2b19a8597158 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -214,7 +214,7 @@ unsafe impl Sync for Device {}
 macro_rules! dev_printk {
     ($method:ident, $dev:expr, $($f:tt)*) => {
         {
-            ($dev).$method(core::format_args!($($f)*));
+            ($dev).$method(::core::format_args!($($f)*));
         }
     }
 }
diff --git a/rust/kernel/device_id.rs b/rust/kernel/device_id.rs
index e5859217a579..0a4eb56d98f2 100644
--- a/rust/kernel/device_id.rs
+++ b/rust/kernel/device_id.rs
@@ -159,7 +159,7 @@ macro_rules! module_device_table {
                     "_", line!(),
                     "_", stringify!($table_name))
         ]
-        static $module_table_name: [core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
-            unsafe { core::mem::transmute_copy($table_name.raw_ids()) };
+        static $module_table_name: [::core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
+            unsafe { ::core::mem::transmute_copy($table_name.raw_ids()) };
     };
 }
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 1604fb6a5b1b..81833a687b75 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -59,7 +59,7 @@ macro_rules! kunit_assert {
             }
 
             static FILE: &'static $crate::str::CStr = $crate::c_str!($file);
-            static LINE: i32 = core::line!() as i32 - $diff;
+            static LINE: i32 = ::core::line!() as i32 - $diff;
             static CONDITION: &'static $crate::str::CStr = $crate::c_str!(stringify!($condition));
 
             // SAFETY: FFI call without safety requirements.
@@ -130,11 +130,11 @@ unsafe impl Sync for UnaryAssert {}
             unsafe {
                 $crate::bindings::__kunit_do_failed_assertion(
                     kunit_test,
-                    core::ptr::addr_of!(LOCATION.0),
+                    ::core::ptr::addr_of!(LOCATION.0),
                     $crate::bindings::kunit_assert_type_KUNIT_ASSERTION,
-                    core::ptr::addr_of!(ASSERTION.0.assert),
+                    ::core::ptr::addr_of!(ASSERTION.0.assert),
                     Some($crate::bindings::kunit_unary_assert_format),
-                    core::ptr::null(),
+                    ::core::ptr::null(),
                 );
             }
 
diff --git a/rust/kernel/static_assert.rs b/rust/kernel/static_assert.rs
index 3115ee0ba8e9..f3f8c6eb7360 100644
--- a/rust/kernel/static_assert.rs
+++ b/rust/kernel/static_assert.rs
@@ -16,7 +16,7 @@
 ///
 /// ```
 /// static_assert!(42 > 24);
-/// static_assert!(core::mem::size_of::<u8>() == 1);
+/// static_assert!(::core::mem::size_of::<u8>() == 1);
 ///
 /// const X: &[u8] = b"bar";
 /// static_assert!(X[1] == b'a');
@@ -29,6 +29,6 @@
 #[macro_export]
 macro_rules! static_assert {
     ($condition:expr) => {
-        const _: () = core::assert!($condition);
+        const _: () = ::core::assert!($condition);
     };
 }
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 878111cb77bc..aed7b2617c32 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -595,7 +595,7 @@ fn deref(&self) -> &str {
 
     macro_rules! format {
         ($($f:tt)*) => ({
-            &*String::from_fmt(kernel::fmt!($($f)*))
+            &*String::from_fmt(::kernel::fmt!($($f)*))
         })
     }
 
@@ -944,5 +944,5 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 /// A convenience alias for [`core::format_args`].
 #[macro_export]
 macro_rules! fmt {
-    ($($f:tt)*) => ( core::format_args!($($f)*) )
+    ($($f:tt)*) => ( ::core::format_args!($($f)*) )
 }
diff --git a/rust/macros/kunit.rs b/rust/macros/kunit.rs
index 4f553ecf40c0..61fc25228e72 100644
--- a/rust/macros/kunit.rs
+++ b/rust/macros/kunit.rs
@@ -88,29 +88,29 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream {
     // Looks like:
     //
     // ```
-    // unsafe extern "C" fn kunit_rust_wrapper_foo(_test: *mut kernel::bindings::kunit) { foo(); }
-    // unsafe extern "C" fn kunit_rust_wrapper_bar(_test: *mut kernel::bindings::kunit) { bar(); }
+    // unsafe extern "C" fn kunit_rust_wrapper_foo(_test: *mut ::kernel::bindings::kunit) { foo(); }
+    // unsafe extern "C" fn kunit_rust_wrapper_bar(_test: *mut ::kernel::bindings::kunit) { bar(); }
     //
-    // static mut TEST_CASES: [kernel::bindings::kunit_case; 3] = [
-    //     kernel::kunit::kunit_case(kernel::c_str!("foo"), kunit_rust_wrapper_foo),
-    //     kernel::kunit::kunit_case(kernel::c_str!("bar"), kunit_rust_wrapper_bar),
-    //     kernel::kunit::kunit_case_null(),
+    // static mut TEST_CASES: [::kernel::bindings::kunit_case; 3] = [
+    //     ::kernel::kunit::kunit_case(::kernel::c_str!("foo"), kunit_rust_wrapper_foo),
+    //     ::kernel::kunit::kunit_case(::kernel::c_str!("bar"), kunit_rust_wrapper_bar),
+    //     ::kernel::kunit::kunit_case_null(),
     // ];
     //
-    // kernel::kunit_unsafe_test_suite!(kunit_test_suit_name, TEST_CASES);
+    // ::kernel::kunit_unsafe_test_suite!(kunit_test_suit_name, TEST_CASES);
     // ```
     let mut kunit_macros = "".to_owned();
     let mut test_cases = "".to_owned();
     for test in &tests {
         let kunit_wrapper_fn_name = format!("kunit_rust_wrapper_{}", test);
         let kunit_wrapper = format!(
-            "unsafe extern \"C\" fn {}(_test: *mut kernel::bindings::kunit) {{ {}(); }}",
+            "unsafe extern \"C\" fn {}(_test: *mut ::kernel::bindings::kunit) {{ {}(); }}",
             kunit_wrapper_fn_name, test
         );
         writeln!(kunit_macros, "{kunit_wrapper}").unwrap();
         writeln!(
             test_cases,
-            "    kernel::kunit::kunit_case(kernel::c_str!(\"{}\"), {}),",
+            "    ::kernel::kunit::kunit_case(::kernel::c_str!(\"{}\"), {}),",
             test, kunit_wrapper_fn_name
         )
         .unwrap();
@@ -119,14 +119,14 @@ pub(crate) fn kunit_tests(attr: TokenStream, ts: TokenStream) -> TokenStream {
     writeln!(kunit_macros).unwrap();
     writeln!(
         kunit_macros,
-        "static mut TEST_CASES: [kernel::bindings::kunit_case; {}] = [\n{test_cases}    kernel::kunit::kunit_case_null(),\n];",
+        "static mut TEST_CASES: [::kernel::bindings::kunit_case; {}] = [\n{test_cases}    ::kernel::kunit::kunit_case_null(),\n];",
         tests.len() + 1
     )
     .unwrap();
 
     writeln!(
         kunit_macros,
-        "kernel::kunit_unsafe_test_suite!({attr}, TEST_CASES);"
+        "::kernel::kunit_unsafe_test_suite!({attr}, TEST_CASES);"
     )
     .unwrap();
 
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index 9acaa68c974e..cb429eceff71 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -283,7 +283,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
 /// macro_rules! pub_no_prefix {
 ///     ($prefix:ident, $($newname:ident),+) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             $(pub(crate) const $newname: u32 = [<$prefix $newname>];)+
 ///         }
 ///     };
@@ -340,7 +340,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
 /// macro_rules! pub_no_prefix {
 ///     ($prefix:ident, $($newname:ident),+) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             $(pub(crate) const fn [<$newname:lower:span>]() -> u32 { [<$prefix $newname:span>] })+
 ///         }
 ///     };
@@ -375,7 +375,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// ```
 /// macro_rules! create_numbered_fn {
 ///     ($name:literal, $val:literal) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             fn [<some_ $name _fn $val>]() -> u32 { $val }
 ///         }
 ///     };
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
index 8ab4e1f3eb45..615cefd4160a 100644
--- a/rust/macros/module.rs
+++ b/rust/macros/module.rs
@@ -224,20 +224,20 @@ pub(crate) fn module(ts: TokenStream) -> TokenStream {
             // SAFETY: `__this_module` is constructed by the kernel at load time and will not be
             // freed until the module is unloaded.
             #[cfg(MODULE)]
-            static THIS_MODULE: kernel::ThisModule = unsafe {{
+            static THIS_MODULE: ::kernel::ThisModule = unsafe {{
                 extern \"C\" {{
-                    static __this_module: kernel::types::Opaque<kernel::bindings::module>;
+                    static __this_module: ::kernel::types::Opaque<::kernel::bindings::module>;
                 }}
 
-                kernel::ThisModule::from_ptr(__this_module.get())
+                ::kernel::ThisModule::from_ptr(__this_module.get())
             }};
             #[cfg(not(MODULE))]
-            static THIS_MODULE: kernel::ThisModule = unsafe {{
-                kernel::ThisModule::from_ptr(core::ptr::null_mut())
+            static THIS_MODULE: ::kernel::ThisModule = unsafe {{
+                ::kernel::ThisModule::from_ptr(::core::ptr::null_mut())
             }};
 
-            impl kernel::ModuleMetadata for {type_} {{
-                const NAME: &'static kernel::str::CStr = kernel::c_str!(\"{name}\");
+            impl ::kernel::ModuleMetadata for {type_} {{
+                const NAME: &'static ::kernel::str::CStr = ::kernel::c_str!(\"{name}\");
             }}
 
             // Double nested modules, since then nobody can access the public items inside.
@@ -255,8 +255,8 @@ mod __module_init {{
                     #[used]
                     static __IS_RUST_MODULE: () = ();
 
-                    static mut __MOD: core::mem::MaybeUninit<{type_}> =
-                        core::mem::MaybeUninit::uninit();
+                    static mut __MOD: ::core::mem::MaybeUninit<{type_}> =
+                        ::core::mem::MaybeUninit::uninit();
 
                     // Loadable modules need to export the `{{init,cleanup}}_module` identifiers.
                     /// # Safety
@@ -267,7 +267,7 @@ mod __module_init {{
                     #[doc(hidden)]
                     #[no_mangle]
                     #[link_section = \".init.text\"]
-                    pub unsafe extern \"C\" fn init_module() -> kernel::ffi::c_int {{
+                    pub unsafe extern \"C\" fn init_module() -> ::kernel::ffi::c_int {{
                         // SAFETY: This function is inaccessible to the outside due to the double
                         // module wrapping it. It is called exactly once by the C side via its
                         // unique name.
@@ -306,11 +306,12 @@ mod __module_init {{
                     #[doc(hidden)]
                     #[link_section = \"{initcall_section}\"]
                     #[used]
-                    pub static __{name}_initcall: extern \"C\" fn() -> kernel::ffi::c_int = __{name}_init;
+                    pub static __{name}_initcall: extern \"C\" fn() -> ::kernel::ffi::c_int =
+                        __{name}_init;
 
                     #[cfg(not(MODULE))]
                     #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)]
-                    core::arch::global_asm!(
+                    ::core::arch::global_asm!(
                         r#\".section \"{initcall_section}\", \"a\"
                         __{name}_initcall:
                             .long   __{name}_init - .
@@ -321,7 +322,7 @@ mod __module_init {{
                     #[cfg(not(MODULE))]
                     #[doc(hidden)]
                     #[no_mangle]
-                    pub extern \"C\" fn __{name}_init() -> kernel::ffi::c_int {{
+                    pub extern \"C\" fn __{name}_init() -> ::kernel::ffi::c_int {{
                         // SAFETY: This function is inaccessible to the outside due to the double
                         // module wrapping it. It is called exactly once by the C side via its
                         // placement above in the initcall section.
@@ -344,9 +345,9 @@ mod __module_init {{
                     /// # Safety
                     ///
                     /// This function must only be called once.
-                    unsafe fn __init() -> kernel::ffi::c_int {{
+                    unsafe fn __init() -> ::kernel::ffi::c_int {{
                         let initer =
-                            <{type_} as kernel::InPlaceModule>::init(&super::super::THIS_MODULE);
+                            <{type_} as ::kernel::InPlaceModule>::init(&super::super::THIS_MODULE);
                         // SAFETY: No data race, since `__MOD` can only be accessed by this module
                         // and there only `__init` and `__exit` access it. These functions are only
                         // called once and `__exit` cannot be called before or during `__init`.
diff --git a/scripts/rustdoc_test_builder.rs b/scripts/rustdoc_test_builder.rs
index e5894652f12c..f9bfff989f38 100644
--- a/scripts/rustdoc_test_builder.rs
+++ b/scripts/rustdoc_test_builder.rs
@@ -28,7 +28,8 @@ fn main() {
     //
     // ```
     // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_28_0() {
-    // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_37_0() -> Result<(), impl core::fmt::Debug> {
+    // fn main() { #[allow(non_snake_case)] fn _doctest_main_rust_kernel_file_rs_37_0() -> \
+    //     Result<(), impl ::core::fmt::Debug> {
     // ```
     //
     // It should be unlikely that doctest code matches such lines (when code is formatted properly).
@@ -49,8 +50,10 @@ fn main() {
 
     // Qualify `Result` to avoid the collision with our own `Result` coming from the prelude.
     let body = body.replace(
-        &format!("{rustdoc_function_name}() -> Result<(), impl core::fmt::Debug> {{"),
-        &format!("{rustdoc_function_name}() -> core::result::Result<(), impl core::fmt::Debug> {{"),
+        &format!("{rustdoc_function_name}() -> Result<(), impl ::core::fmt::Debug> {{"),
+        &format!(
+            "{rustdoc_function_name}() -> ::core::result::Result<(), impl ::core::fmt::Debug> {{"
+        ),
     );
 
     // For tests that get generated with `Result`, like above, `rustdoc` generates an `unwrap()` on
diff --git a/scripts/rustdoc_test_gen.rs b/scripts/rustdoc_test_gen.rs
index 036635fb1621..f8d053f75270 100644
--- a/scripts/rustdoc_test_gen.rs
+++ b/scripts/rustdoc_test_gen.rs
@@ -167,12 +167,14 @@ fn main() {
             rust_tests,
             r#"/// Generated `{name}` KUnit test case from a Rust documentation test.
 #[no_mangle]
-pub extern "C" fn {kunit_name}(__kunit_test: *mut kernel::bindings::kunit) {{
+pub extern "C" fn {kunit_name}(__kunit_test: *mut ::kernel::bindings::kunit) {{
     /// Overrides the usual [`assert!`] macro with one that calls KUnit instead.
     #[allow(unused)]
     macro_rules! assert {{
         ($cond:expr $(,)?) => {{{{
-            kernel::kunit_assert!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond);
+            ::kernel::kunit_assert!(
+                "{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond
+            );
         }}}}
     }}
 
@@ -180,13 +182,15 @@ macro_rules! assert {{
     #[allow(unused)]
     macro_rules! assert_eq {{
         ($left:expr, $right:expr $(,)?) => {{{{
-            kernel::kunit_assert_eq!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right);
+            ::kernel::kunit_assert_eq!(
+                "{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right
+            );
         }}}}
     }}
 
     // Many tests need the prelude, so provide it by default.
     #[allow(unused)]
-    use kernel::prelude::*;
+    use ::kernel::prelude::*;
 
     // Unconditionally print the location of the original doctest (i.e. rather than the location in
     // the generated file) so that developers can easily map the test back to the source code.
@@ -197,11 +201,11 @@ macro_rules! assert_eq {{
     // This follows the syntax for declaring test metadata in the proposed KTAP v2 spec, which may
     // be used for the proposed KUnit test attributes API. Thus hopefully this will make migration
     // easier later on.
-    kernel::kunit::info(format_args!("    # {kunit_name}.location: {real_path}:{line}\n"));
+    ::kernel::kunit::info(format_args!("    # {kunit_name}.location: {real_path}:{line}\n"));
 
     /// The anchor where the test code body starts.
     #[allow(unused)]
-    static __DOCTEST_ANCHOR: i32 = core::line!() as i32 + {body_offset} + 1;
+    static __DOCTEST_ANCHOR: i32 = ::core::line!() as i32 + {body_offset} + 1;
     {{
         {body}
         main();
-- 
2.43.0

[PATCH] docs: rust: quick-start: update Ubuntu instructions

[Igor Korotin]

Ubuntu’s rust-1.80 packages don't install tools by default, so the
PATH must include /usr/lib/rust-1.80/bin. Also, bindgen-0.65 needs
update-alternatives to set it as the default.

Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
---
 Documentation/rust/quick-start.rst | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Documentation/rust/quick-start.rst b/Documentation/rust/quick-start.rst
index 4aa50e5fcb8c..2846fd873680 100644
--- a/Documentation/rust/quick-start.rst
+++ b/Documentation/rust/quick-start.rst
@@ -95,6 +95,16 @@ they should generally work out of the box, e.g.::
 
 	apt install rustc-1.80 rust-1.80-src bindgen-0.65 rustfmt-1.80 rust-1.80-clippy
 
+By default bindgen-0.65 deb package does not set itself as default. It should be
+installed as an alternative:
+
+	update-alternatives --install /usr/bin/bindgen bindgen /usr/bin/bindgen-0.65 100
+	update-alternatives --set bindgen /usr/bin/bindgen-0.65
+
+``PATH`` needs to be set when installing rust with apt, e.g.::
+
+	PATH=/usr/lib/rust-1.80/bin:$PATH
+
 ``RUST_LIB_SRC`` needs to be set when using the versioned packages, e.g.::
 
 	RUST_LIB_SRC=/usr/src/rustc-$(rustc-1.80 --version | cut -d' ' -f2)/library
-- 
2.43.0

Re: [PATCH] docs: rust: quick-start: update Ubuntu instructions

[Miguel Ojeda]

On Mon, Mar 31, 2025 at 7:01 PM Igor Korotin <igor.korotin@yahoo.com> wrote:
>
> Ubuntu’s rust-1.80 packages don't install tools by default, so the
> PATH must include /usr/lib/rust-1.80/bin. Also, bindgen-0.65 needs
> update-alternatives to set it as the default.

They are available in `$PATH`, but under a different name, so it is
not necessarily needed to change the `$PATH` or set an alternative.

So one can do e.g.:

    make LLVM=1 RUSTC=rustc-1.80 BINDGEN=bindgen-0.65

For docs, I tend to prefer setups that minimize global changes, but
perhaps we can mention both approaches briefly?

Thanks for the patch!

Cheers,
Miguel

Re: [PATCH] docs: rust: quick-start: update Ubuntu instructions

[Miguel Ojeda]

On Tue, Apr 1, 2025 at 11:54 AM Igor Korotin <igor.korotin@yahoo.com> wrote:
>
> One of the issues is that bindgen-0.65, by default, uses Ubuntu’s Rust compiler (version 1.75), which is not
> compatible with the latest kernel sources.

Hmm... I am not sure what you mean, but `bindgen` does not use the
Rust compiler. Of course, both are used by the kernel build, but they
are independent.

> Do the environment variables RUSTC=rustc-1.80 and BINDGEN=bindgen-0.65 ensure that the correct
> versions of rustdoc, rust-clang, rust-lld, and rust-llvm-dwp are used? If not, perhaps those should
> be explicitly set as well.

To customize the binaries, you want `RUSTC` and `BINDGEN`, and you may
additionally need `RUSTDOC`, `RUSTFMT` and `CLIPPY_DRIVER` depending
on what you build, but the rest you mention are not used by the kernel
build.

They cannot be passed as environment variables, though -- one needs to
pass them as arguments to `make`. Which is definitely painful to do
manually for normal development.

> I'll try to come with some different format of this configuration mentioning the command:
>     "make LLVM=1 RUSTC=rustc-1.80 BINDGEN=bindgen-0.65"

Perhaps mention the full one, if we are going to do it anyway.

By the way, please do not use HTML -- your emails will be dropped by
lists automatically if you do so.

Thanks!

Cheers,
Miguel

Re: [PATCH] docs: rust: quick-start: update Ubuntu instructions

[Igor Korotin]

On 4/1/25 12:26, Miguel Ojeda wrote:
> On Tue, Apr 1, 2025 at 11:54 AM Igor Korotin <igor.korotin@yahoo.com> wrote:
>>
>> One of the issues is that bindgen-0.65, by default, uses Ubuntu’s Rust compiler (version 1.75), which is not
>> compatible with the latest kernel sources.
> 
> Hmm... I am not sure what you mean, but `bindgen` does not use the
> Rust compiler. Of course, both are used by the kernel build, but they
> are independent.

Though `bindgen` might not use rust compiler, nonetheless bindgen-0.65
deb package requires rustc in its dependencies:

     root@c4a63fba5ac2:/# apt-cache depends bindgen-0.65
     bindgen-0.65
       Depends: clang-17
       Depends: rustc
         rustc-1.74
       Depends: libc6
       Depends: libgcc-s1

Even if one uses the command:

     apt install rustc-1.80 rust-1.80-src bindgen-0.65 rustfmt-1.80 
rust-1.80-clippy

It anyway installs both rustc(as default) and rustc-1.80. Can be easily
reproduced in ubuntu:24.04 docker container.


I’ll send a reworked patch for quick-start.rst once it’s ready.

Best Regards
Igor

Re: [PATCH] docs: rust: quick-start: update Ubuntu instructions

[Miguel Ojeda]

On Tue, Apr 1, 2025 at 3:38 PM Igor Korotin <igor.korotin@yahoo.com> wrote:
>
> Though `bindgen` might not use rust compiler, nonetheless bindgen-0.65
> deb package requires rustc in its dependencies:

That is not the case for their `bindgen` package (i.e. non-versioned),
so I don't know why they do that.

Cheers,
Miguel

Re: [PATCH] docs: rust: quick-start: update Ubuntu instructions

[Benno Lossin]

On Mon Mar 31, 2025 at 7:01 PM CEST, Igor Korotin wrote:
> Ubuntu’s rust-1.80 packages don't install tools by default, so the
> PATH must include /usr/lib/rust-1.80/bin. Also, bindgen-0.65 needs
> update-alternatives to set it as the default.
>
> Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
> ---
>  Documentation/rust/quick-start.rst | 10 ++++++++++
>  1 file changed, 10 insertions(+)

Please don't send patches in reply to emails. That only makes sense if
a) the replied-to email is a cover letter of the series that the patch
   is a part of, or
b) if the patch is relevant to the discussion in the thread.

Neither applies here.

---
Cheers,
Benno

Re: [PATCH v2 1/1] rust: macros: Fix macro referencing core and kernel crates v2

[Miguel Ojeda]

On Fri, Mar 28, 2025 at 7:05 PM Igor Korotin <igor.korotin@yahoo.com> wrote:
>
> Update macros to always use absolute paths for crates `core` and `kernel`.
> This guarantees that macros will not pick up user-defined crates `core`
> or `kernel` by accident.
>
> Changes since v1:
> - Fixed paths in auto-generated code.
>
> Suggested-by: Benno Lossin <benno.lossin@proton.me>
> Closes: https://github.com/Rust-for-Linux/linux/issues/1150
> Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>

Thanks for the patch!

A few procedural notes:

  - The title has a v2 at the end -- please do not add versions in the
title of the commit, the "[PATCH v2...] is enough for that :)

  - The "Changes since v1" should be part of the non-commit-log part,
i.e. after the `---` line below.

  - If you send a single patch, then you don't need to add a cover
letter necessarily (typically you just use the place after `---` in
the patch).

  - Speaking of the cover letter, it seems like the 0/1 patch looks
like a reply to Benno rather than an actual cover letter, and does not
follow the usual cover letter format. That is quite confusing.

  - You should send the patch to the relevant maintainers and
reviewers -- you can use `scripts/get_maintainer.pl` or something like
https://rust-for-linux.com/contributing#submitting-patches.

Please take a look at another v2 to see how people normally do it. For
instance, this recent one looks fairly standard:

    https://lore.kernel.org/rust-for-linux/20250325133352.441425-1-andrewjballance@gmail.com/

Thanks!

Cheers,
Miguel

Re: [PATCH v2 0/1] rust: macros: Fix macro referencing core and kernel crates v2

[Benno Lossin]

This email seems to be a cover letter for the next version of your
patch. In that case, you should send it as its own thread to the list
(and not in reply to my previous email).

On Fri Mar 28, 2025 at 7:03 PM CET, Igor Korotin wrote:
>> > To prevent issues where user-defined modules named `core` or `kernel`
>> > could be picked up instead of the standard ones, update macros to use
>> > absolute paths, `::core::...` and `::kernel::...`, for core and kernel
>> > references.
>> 
>> Please split this sentence up into smaller parts. Also "standard ones"
>> sounds weird to me, `core` and `kernel` are crates and not modules.
>
> Simplified the commit message.

You don't need to reply if you're fine with the suggestion :)

>> > Suggested-by: y86-dev <y86-dev@protonmail.com>
>> 
>> Please use my real name and other mail address instead:
>>    
>>     Benno Lossin <benno.lossin@proton.me>
>
> Sure. Tried to find your creds via your github profile/commits without 
> success.
>
>> > Closes: https://github.com/Rust-for-Linux/linux/issues/1150
>> > Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
>> > ---
>> >  rust/ffi.rs                  | 2 +-
>> >  rust/kernel/device.rs        | 2 +-
>> >  rust/kernel/device_id.rs    | 4 ++--
>> >  rust/kernel/kunit.rs        | 8 ++++----
>> >  rust/kernel/static_assert.rs | 4 ++--
>> >  rust/kernel/str.rs          | 4 ++--
>> >  rust/macros/lib.rs          | 6 +++---
>> >  scripts/rustdoc_test_gen.rs  | 8 ++++++--
>> >  8 files changed, 21 insertions(+), 17 deletions(-)
>> 
>> There are also some occurrences of `kernel::` & `core::` in proc macros,
>> for example:
>> - rust/macros/kunit.rs:129
>> - rust/macros/module.rs:347
>> - ...
>> 
>> Could you also add those to the patch? Thanks!
>> 
>> (line numbers after applying your patch to rust-next)
>
> Agreed. Fixed references in auto-generated code in files
> 1. rust/macros/kunit.rs            
> 2. rust/macros/module.rs           
> 3. scripts/rustdoc_test_builder.rs 
> 4. scripts/rustdoc_test_gen.rs     

Yeah those last two are also good finds.

---
Cheers,
Benno

[PATCH] rust: macros: Fix macro referencing core and kernel crates

[Igor Korotin]

To prevent issues where user-defined modules named `core` or `kernel`
could be picked up instead of the standard ones, update macros to use
absolute paths, `::core::...` and `::kernel::...`, for core and kernel
references.

Suggested-by: y86-dev <y86-dev@protonmail.com>
Closes: https://github.com/Rust-for-Linux/linux/issues/1150
Signed-off-by: Igor Korotin <igor.korotin@yahoo.com>
---
 rust/ffi.rs                  | 2 +-
 rust/kernel/device.rs        | 2 +-
 rust/kernel/device_id.rs     | 4 ++--
 rust/kernel/kunit.rs         | 8 ++++----
 rust/kernel/static_assert.rs | 4 ++--
 rust/kernel/str.rs           | 4 ++--
 rust/macros/lib.rs           | 6 +++---
 scripts/rustdoc_test_gen.rs  | 8 ++++++--
 8 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/rust/ffi.rs b/rust/ffi.rs
index 584f75b49862..d60aad792af4 100644
--- a/rust/ffi.rs
+++ b/rust/ffi.rs
@@ -17,7 +17,7 @@ macro_rules! alias {
 
         // Check size compatibility with `core`.
         const _: () = assert!(
-            core::mem::size_of::<$name>() == core::mem::size_of::<core::ffi::$name>()
+            ::core::mem::size_of::<$name>() == ::core::mem::size_of::<::core::ffi::$name>()
         );
     )*}
 }
diff --git a/rust/kernel/device.rs b/rust/kernel/device.rs
index db2d9658ba47..2b19a8597158 100644
--- a/rust/kernel/device.rs
+++ b/rust/kernel/device.rs
@@ -214,7 +214,7 @@ unsafe impl Sync for Device {}
 macro_rules! dev_printk {
     ($method:ident, $dev:expr, $($f:tt)*) => {
         {
-            ($dev).$method(core::format_args!($($f)*));
+            ($dev).$method(::core::format_args!($($f)*));
         }
     }
 }
diff --git a/rust/kernel/device_id.rs b/rust/kernel/device_id.rs
index e5859217a579..0a4eb56d98f2 100644
--- a/rust/kernel/device_id.rs
+++ b/rust/kernel/device_id.rs
@@ -159,7 +159,7 @@ macro_rules! module_device_table {
                     "_", line!(),
                     "_", stringify!($table_name))
         ]
-        static $module_table_name: [core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
-            unsafe { core::mem::transmute_copy($table_name.raw_ids()) };
+        static $module_table_name: [::core::mem::MaybeUninit<u8>; $table_name.raw_ids().size()] =
+            unsafe { ::core::mem::transmute_copy($table_name.raw_ids()) };
     };
 }
diff --git a/rust/kernel/kunit.rs b/rust/kernel/kunit.rs
index 1604fb6a5b1b..81833a687b75 100644
--- a/rust/kernel/kunit.rs
+++ b/rust/kernel/kunit.rs
@@ -59,7 +59,7 @@ macro_rules! kunit_assert {
             }
 
             static FILE: &'static $crate::str::CStr = $crate::c_str!($file);
-            static LINE: i32 = core::line!() as i32 - $diff;
+            static LINE: i32 = ::core::line!() as i32 - $diff;
             static CONDITION: &'static $crate::str::CStr = $crate::c_str!(stringify!($condition));
 
             // SAFETY: FFI call without safety requirements.
@@ -130,11 +130,11 @@ unsafe impl Sync for UnaryAssert {}
             unsafe {
                 $crate::bindings::__kunit_do_failed_assertion(
                     kunit_test,
-                    core::ptr::addr_of!(LOCATION.0),
+                    ::core::ptr::addr_of!(LOCATION.0),
                     $crate::bindings::kunit_assert_type_KUNIT_ASSERTION,
-                    core::ptr::addr_of!(ASSERTION.0.assert),
+                    ::core::ptr::addr_of!(ASSERTION.0.assert),
                     Some($crate::bindings::kunit_unary_assert_format),
-                    core::ptr::null(),
+                    ::core::ptr::null(),
                 );
             }
 
diff --git a/rust/kernel/static_assert.rs b/rust/kernel/static_assert.rs
index 3115ee0ba8e9..f3f8c6eb7360 100644
--- a/rust/kernel/static_assert.rs
+++ b/rust/kernel/static_assert.rs
@@ -16,7 +16,7 @@
 ///
 /// ```
 /// static_assert!(42 > 24);
-/// static_assert!(core::mem::size_of::<u8>() == 1);
+/// static_assert!(::core::mem::size_of::<u8>() == 1);
 ///
 /// const X: &[u8] = b"bar";
 /// static_assert!(X[1] == b'a');
@@ -29,6 +29,6 @@
 #[macro_export]
 macro_rules! static_assert {
     ($condition:expr) => {
-        const _: () = core::assert!($condition);
+        const _: () = ::core::assert!($condition);
     };
 }
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index 878111cb77bc..aed7b2617c32 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -595,7 +595,7 @@ fn deref(&self) -> &str {
 
     macro_rules! format {
         ($($f:tt)*) => ({
-            &*String::from_fmt(kernel::fmt!($($f)*))
+            &*String::from_fmt(::kernel::fmt!($($f)*))
         })
     }
 
@@ -944,5 +944,5 @@ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
 /// A convenience alias for [`core::format_args`].
 #[macro_export]
 macro_rules! fmt {
-    ($($f:tt)*) => ( core::format_args!($($f)*) )
+    ($($f:tt)*) => ( ::core::format_args!($($f)*) )
 }
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
index 9acaa68c974e..cb429eceff71 100644
--- a/rust/macros/lib.rs
+++ b/rust/macros/lib.rs
@@ -283,7 +283,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
 /// macro_rules! pub_no_prefix {
 ///     ($prefix:ident, $($newname:ident),+) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             $(pub(crate) const $newname: u32 = [<$prefix $newname>];)+
 ///         }
 ///     };
@@ -340,7 +340,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
 /// macro_rules! pub_no_prefix {
 ///     ($prefix:ident, $($newname:ident),+) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             $(pub(crate) const fn [<$newname:lower:span>]() -> u32 { [<$prefix $newname:span>] })+
 ///         }
 ///     };
@@ -375,7 +375,7 @@ pub fn concat_idents(ts: TokenStream) -> TokenStream {
 /// ```
 /// macro_rules! create_numbered_fn {
 ///     ($name:literal, $val:literal) => {
-///         kernel::macros::paste! {
+///         ::kernel::macros::paste! {
 ///             fn [<some_ $name _fn $val>]() -> u32 { $val }
 ///         }
 ///     };
diff --git a/scripts/rustdoc_test_gen.rs b/scripts/rustdoc_test_gen.rs
index 036635fb1621..981b9a3d57b4 100644
--- a/scripts/rustdoc_test_gen.rs
+++ b/scripts/rustdoc_test_gen.rs
@@ -172,7 +172,9 @@ pub extern "C" fn {kunit_name}(__kunit_test: *mut kernel::bindings::kunit) {{
     #[allow(unused)]
     macro_rules! assert {{
         ($cond:expr $(,)?) => {{{{
-            kernel::kunit_assert!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond);
+            ::kernel::kunit_assert!(
+                "{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $cond
+            );
         }}}}
     }}
 
@@ -180,7 +182,9 @@ macro_rules! assert {{
     #[allow(unused)]
     macro_rules! assert_eq {{
         ($left:expr, $right:expr $(,)?) => {{{{
-            kernel::kunit_assert_eq!("{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right);
+            ::kernel::kunit_assert_eq!(
+                "{kunit_name}", "{real_path}", __DOCTEST_ANCHOR - {line}, $left, $right
+            );
         }}}}
     }}
 
-- 
2.43.0