Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

10 files changed, 2096 insertions, 0 deletions

diff --git a/rust/macros/concat_idents.rs b/rust/macros/concat_idents.rs
new file mode 100644
index 000000000..47b6add37
--- /dev/null
+++ b/rust/macros/concat_idents.rs
@@ -0,0 +1,36 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use proc_macro2::{
+    Ident,
+    TokenStream,
+    TokenTree, //
+};
+use syn::{
+    parse::{
+        Parse,
+        ParseStream, //
+    },
+    Result,
+    Token, //
+};
+
+pub(crate) struct Input {
+    a: Ident,
+    _comma: Token![,],
+    b: Ident,
+}
+
+impl Parse for Input {
+    fn parse(input: ParseStream<'_>) -> Result<Self> {
+        Ok(Self {
+            a: input.parse()?,
+            _comma: input.parse()?,
+            b: input.parse()?,
+        })
+    }
+}
+
+pub(crate) fn concat_idents(Input { a, b, .. }: Input) -> TokenStream {
+    let res = Ident::new(&format!("{a}{b}"), b.span());
+    TokenStream::from_iter([TokenTree::Ident(res)])
+}
diff --git a/rust/macros/export.rs b/rust/macros/export.rs
new file mode 100644
index 000000000..6d53521f6
--- /dev/null
+++ b/rust/macros/export.rs
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use proc_macro2::TokenStream;
+use quote::quote;
+
+/// Please see [`crate::export`] for documentation.
+pub(crate) fn export(f: syn::ItemFn) -> TokenStream {
+    let name = &f.sig.ident;
+
+    quote! {
+        // This verifies that the function has the same signature as the declaration generated by
+        // bindgen. It makes use of the fact that all branches of an if/else must have the same
+        // type.
+        const _: () = {
+            if true {
+                ::kernel::bindings::#name
+            } else {
+                #name
+            };
+        };
+
+        #[no_mangle]
+        #f
+    }
+}
diff --git a/rust/macros/fmt.rs b/rust/macros/fmt.rs
new file mode 100644
index 000000000..ce6c72493
--- /dev/null
+++ b/rust/macros/fmt.rs
@@ -0,0 +1,96 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use std::collections::BTreeSet;
+
+use proc_macro2::{Ident, TokenStream, TokenTree};
+use quote::quote_spanned;
+
+/// Please see [`crate::fmt`] for documentation.
+pub(crate) fn fmt(input: TokenStream) -> TokenStream {
+    let mut input = input.into_iter();
+
+    let first_opt = input.next();
+    let first_owned_str;
+    let mut names = BTreeSet::new();
+    let first_span = {
+        let Some((mut first_str, first_span)) = (match first_opt.as_ref() {
+            Some(TokenTree::Literal(first_lit)) => {
+                first_owned_str = first_lit.to_string();
+                Some(first_owned_str.as_str()).and_then(|first| {
+                    let first = first.strip_prefix('"')?;
+                    let first = first.strip_suffix('"')?;
+                    Some((first, first_lit.span()))
+                })
+            }
+            _ => None,
+        }) else {
+            return first_opt.into_iter().chain(input).collect();
+        };
+
+        // Parse `identifier`s from the format string.
+        //
+        // See https://doc.rust-lang.org/std/fmt/index.html#syntax.
+        while let Some((_, rest)) = first_str.split_once('{') {
+            first_str = rest;
+            if let Some(rest) = first_str.strip_prefix('{') {
+                first_str = rest;
+                continue;
+            }
+            if let Some((name, rest)) = first_str.split_once('}') {
+                first_str = rest;
+                let name = name.split_once(':').map_or(name, |(name, _)| name);
+                if !name.is_empty() && !name.chars().all(|c| c.is_ascii_digit()) {
+                    names.insert(name);
+                }
+            }
+        }
+        first_span
+    };
+
+    let adapter = quote_spanned!(first_span => ::kernel::fmt::Adapter);
+
+    let mut args = TokenStream::from_iter(first_opt);
+    {
+        let mut flush = |args: &mut TokenStream, current: &mut TokenStream| {
+            let current = std::mem::take(current);
+            if !current.is_empty() {
+                let (lhs, rhs) = (|| {
+                    let mut current = current.into_iter();
+                    let mut acc = TokenStream::new();
+                    while let Some(tt) = current.next() {
+                        // Split on `=` only once to handle cases like `a = b = c`.
+                        if matches!(&tt, TokenTree::Punct(p) if p.as_char() == '=') {
+                            names.remove(acc.to_string().as_str());
+                            // Include the `=` itself to keep the handling below uniform.
+                            acc.extend([tt]);
+                            return (Some(acc), current.collect::<TokenStream>());
+                        }
+                        acc.extend([tt]);
+                    }
+                    (None, acc)
+                })();
+                args.extend(quote_spanned!(first_span => #lhs #adapter(&(#rhs))));
+            }
+        };
+
+        let mut current = TokenStream::new();
+        for tt in input {
+            match &tt {
+                TokenTree::Punct(p) if p.as_char() == ',' => {
+                    flush(&mut args, &mut current);
+                    &mut args
+                }
+                _ => &mut current,
+            }
+            .extend([tt]);
+        }
+        flush(&mut args, &mut current);
+    }
+
+    for name in names {
+        let name = Ident::new(name, first_span);
+        args.extend(quote_spanned!(first_span => , #name = #adapter(&#name)));
+    }
+
+    quote_spanned!(first_span => ::core::format_args!(#args))
+}
diff --git a/rust/macros/for_lt.rs b/rust/macros/for_lt.rs
new file mode 100644
index 000000000..4372cbad3
--- /dev/null
+++ b/rust/macros/for_lt.rs
@@ -0,0 +1,265 @@
+// SPDX-License-Identifier: Apache-2.0 OR MIT
+
+use proc_macro2::{
+    Span,
+    TokenStream, //
+};
+use quote::{
+    format_ident,
+    quote, //
+};
+use syn::{
+    parse::{
+        Parse,
+        ParseStream, //
+    },
+    visit::Visit,
+    visit_mut::VisitMut,
+    Lifetime,
+    Result,
+    Token,
+    Type, //
+};
+
+pub(crate) enum HigherRankedType {
+    Explicit {
+        _for_token: Token![for],
+        _lt_token: Token![<],
+        lifetime: Lifetime,
+        _gt_token: Token![>],
+        ty: Type,
+    },
+    Implicit {
+        ty: Type,
+    },
+}
+
+impl Parse for HigherRankedType {
+    fn parse(input: ParseStream<'_>) -> Result<Self> {
+        if input.peek(Token![for]) {
+            Ok(Self::Explicit {
+                _for_token: input.parse()?,
+                _lt_token: input.parse()?,
+                lifetime: input.parse()?,
+                _gt_token: input.parse()?,
+                ty: input.parse()?,
+            })
+        } else {
+            Ok(Self::Implicit { ty: input.parse()? })
+        }
+    }
+}
+
+trait TypeExt {
+    fn expand_elided_lifetime(&self, explicit_lt: &Lifetime) -> Type;
+    fn replace_lifetime(&self, src: &Lifetime, dst: &Lifetime) -> Type;
+    fn has_lifetime(&self, lt: &Lifetime) -> bool;
+}
+
+impl TypeExt for Type {
+    fn expand_elided_lifetime(&self, explicit_lt: &Lifetime) -> Type {
+        struct ElidedLifetimeExpander<'a>(&'a Lifetime);
+
+        impl VisitMut for ElidedLifetimeExpander<'_> {
+            fn visit_lifetime_mut(&mut self, lifetime: &mut Lifetime) {
+                // Expand explicit `'_`
+                if lifetime.ident == "_" {
+                    *lifetime = self.0.clone();
+                }
+            }
+
+            fn visit_type_reference_mut(&mut self, reference: &mut syn::TypeReference) {
+                syn::visit_mut::visit_type_reference_mut(self, reference);
+
+                if reference.lifetime.is_none() {
+                    reference.lifetime = Some(self.0.clone());
+                }
+            }
+        }
+
+        let mut ret = self.clone();
+        ElidedLifetimeExpander(explicit_lt).visit_type_mut(&mut ret);
+        ret
+    }
+
+    fn replace_lifetime(&self, src: &Lifetime, dst: &Lifetime) -> Type {
+        struct LifetimeReplacer<'a>(&'a Lifetime, &'a Lifetime);
+
+        impl VisitMut for LifetimeReplacer<'_> {
+            fn visit_lifetime_mut(&mut self, lifetime: &mut Lifetime) {
+                if lifetime.ident == self.0.ident {
+                    *lifetime = self.1.clone();
+                }
+            }
+        }
+
+        let mut ret = self.clone();
+        LifetimeReplacer(src, dst).visit_type_mut(&mut ret);
+        ret
+    }
+
+    fn has_lifetime(&self, lt: &Lifetime) -> bool {
+        struct HasLifetime<'a>(&'a Lifetime, bool);
+
+        impl Visit<'_> for HasLifetime<'_> {
+            fn visit_lifetime(&mut self, lifetime: &Lifetime) {
+                if lifetime.ident == self.0.ident {
+                    self.1 = true;
+                }
+            }
+
+            // Macro invocations are opaque; conservatively assume they may
+            // reference the lifetime.
+            fn visit_macro(&mut self, _: &syn::Macro) {
+                self.1 = true;
+            }
+        }
+
+        let mut visitor = HasLifetime(lt, false);
+        visitor.visit_type(self);
+        visitor.1
+    }
+}
+
+struct Prover<'a>(&'a Lifetime, Vec<&'a Type>);
+
+impl<'a> Prover<'a> {
+    /// Prove that `ty` is covariant over `'lt`.
+    ///
+    /// This also needs to prove that it'll be wellformed for any instance of `'lt`.
+    /// It can be assumed that `ty` will be wellformed if `'lt` is substituted to `'static`.
+    fn prove(&mut self, ty: &'a Type) {
+        match ty {
+            Type::Paren(ty) => self.prove(&ty.elem),
+            Type::Group(ty) => self.prove(&ty.elem),
+
+            // No lifetime involved
+            Type::Never(_) => {}
+
+            // `[T; N]` and `[T]` is covariant over `T`.
+            Type::Array(ty) => self.prove(&ty.elem),
+            Type::Slice(ty) => self.prove(&ty.elem),
+
+            Type::Tuple(ty) => {
+                for elem in &ty.elems {
+                    self.prove(elem);
+                }
+            }
+
+            // `*const T` is covariant over `T`
+            Type::Ptr(ty) if ty.const_token.is_some() => self.prove(&ty.elem),
+
+            // `&T` is covariant over `T` and lifetime.
+            //
+            // Note that if we encounter `&'other_lt T`, then we still need to make sure the type
+            // is wellformed if `T` involves `&'lt`, so we defer to the compiler.
+            //
+            // This is to block cases like `CovariantForLt!(for<'a> &'static &'a u32)`, as the
+            // presence of the type implies `'a: 'static` but this is unsound.
+            Type::Reference(ty)
+                if ty.mutability.is_none() && ty.lifetime.as_ref() == Some(self.0) =>
+            {
+                self.prove(&ty.elem)
+            }
+
+            // `&[mut] T` is covariant over lifetime.
+            // In case we have `&[mut] NoLifetime`, we don't need to do additional checks.
+            Type::Reference(ty) if !ty.elem.has_lifetime(self.0) => (),
+
+            // No mention of lifetime at all, no need to perform compiler check.
+            ty if !ty.has_lifetime(self.0) => (),
+
+            // Otherwise, we need to emit checks so that compiler can determine if the types are
+            // actually covariant.
+            ty => self.1.push(ty),
+        }
+    }
+}
+
+/// Shared implementation for both `ForLt!` and `CovariantForLt!`.
+///
+/// Both macros run the prover and emit `ProveWf` structs to check well-formedness for all lifetime
+/// instances (workaround for <https://github.com/rust-lang/rust/issues/152489>). `CovariantForLt!`
+/// additionally emits covariance proof functions and sets `N = 1`.
+fn for_lt_inner(input: HigherRankedType, prove_covariance: bool) -> TokenStream {
+    let (ty, lifetime) = match input {
+        HigherRankedType::Explicit { lifetime, ty, .. } => (ty, lifetime),
+        HigherRankedType::Implicit { ty } => {
+            // If there's no explicit `for<'a>` binder, inject a synthetic `'__elided` lifetime
+            // and expand elided sites.
+            let lifetime = Lifetime {
+                apostrophe: Span::mixed_site(),
+                ident: format_ident!("__elided", span = Span::mixed_site()),
+            };
+            (ty.expand_elided_lifetime(&lifetime), lifetime)
+        }
+    };
+
+    let mut prover = Prover(&lifetime, Vec::new());
+    prover.prove(&ty);
+
+    let mut proof = Vec::new();
+
+    // Emit proofs for every type that requires additional compiler help in proving covariance.
+    for (idx, required_proof) in prover.1.into_iter().enumerate() {
+        // Insert a proof that the type is well-formed.
+        //
+        // This is intended to workaround a Rust compiler soundness bug related to HRTB.
+        // https://github.com/rust-lang/rust/issues/152489
+        //
+        // This needs to be a struct instead of fn to avoid the implied WF bounds.
+        let wf_proof_name = format_ident!("ProveWf{idx}");
+        proof.push(quote!(
+            struct #wf_proof_name<#lifetime>(
+                ::core::marker::PhantomData<&#lifetime ()>, #required_proof
+            );
+        ));
+
+        // Insert a proof that the type is covariant.
+        if prove_covariance {
+            let cov_proof_name = format_ident!("prove_covariant_{idx}");
+            proof.push(quote!(
+                fn #cov_proof_name<'__short, '__long: '__short>(
+                    long: #wf_proof_name<'__long>
+                ) -> #wf_proof_name<'__short> {
+                    long
+                }
+            ));
+        }
+    }
+
+    // Make sure that the type is wellformed when substituting lifetime with `'static`.
+    //
+    // Currently the Rust compiler doesn't check this, see the above `ProveWf` documentation.
+    //
+    // We prefer to use this way of proving WF-ness as it can work when generics are involved.
+    let ty_static = ty.replace_lifetime(
+        &lifetime,
+        &Lifetime {
+            apostrophe: Span::mixed_site(),
+            ident: format_ident!("static"),
+        },
+    );
+
+    let n: usize = prove_covariance.into();
+
+    quote!(
+        ::kernel::types::for_lt::UnsafeForLtImpl::<
+            dyn for<#lifetime> ::kernel::types::for_lt::WithLt<#lifetime, Of = #ty>,
+            #ty_static,
+            {
+                #(#proof)*
+
+                #n
+            }
+        >
+    )
+}
+
+pub(crate) fn for_lt(input: HigherRankedType) -> TokenStream {
+    for_lt_inner(input, false)
+}
+
+pub(crate) fn covariant_for_lt(input: HigherRankedType) -> TokenStream {
+    for_lt_inner(input, true)
+}
diff --git a/rust/macros/helpers.rs b/rust/macros/helpers.rs
new file mode 100644
index 000000000..d18fbf4da
--- /dev/null
+++ b/rust/macros/helpers.rs
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use proc_macro2::TokenStream;
+use quote::ToTokens;
+use syn::{
+    parse::{
+        Parse,
+        ParseStream, //
+    },
+    Attribute,
+    Error,
+    LitStr,
+    Result, //
+};
+
+/// A string literal that is required to have ASCII value only.
+pub(crate) struct AsciiLitStr(LitStr);
+
+impl Parse for AsciiLitStr {
+    fn parse(input: ParseStream<'_>) -> Result<Self> {
+        let s: LitStr = input.parse()?;
+        if !s.value().is_ascii() {
+            return Err(Error::new_spanned(s, "expected ASCII-only string literal"));
+        }
+        Ok(Self(s))
+    }
+}
+
+impl ToTokens for AsciiLitStr {
+    fn to_tokens(&self, ts: &mut TokenStream) {
+        self.0.to_tokens(ts);
+    }
+}
+
+impl AsciiLitStr {
+    pub(crate) fn value(&self) -> String {
+        self.0.value()
+    }
+}
+
+pub(crate) fn file() -> String {
+    #[cfg(not(CONFIG_RUSTC_HAS_SPAN_FILE))]
+    {
+        proc_macro::Span::call_site()
+            .source_file()
+            .path()
+            .to_string_lossy()
+            .into_owned()
+    }
+
+    #[cfg(CONFIG_RUSTC_HAS_SPAN_FILE)]
+    {
+        proc_macro::Span::call_site().file()
+    }
+}
+
+/// Obtain all `#[cfg]` attributes.
+pub(crate) fn gather_cfg_attrs(attr: &[Attribute]) -> impl Iterator<Item = &Attribute> + '_ {
+    attr.iter().filter(|a| a.path().is_ident("cfg"))
+}
diff --git a/rust/macros/kunit.rs b/rust/macros/kunit.rs
new file mode 100644
index 000000000..ae20ed676
--- /dev/null
+++ b/rust/macros/kunit.rs
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Procedural macro to run KUnit tests using a user-space like syntax.
+//!
+//! Copyright (c) 2023 José Expósito <jose.exposito89@gmail.com>
+
+use std::ffi::CString;
+
+use proc_macro2::TokenStream;
+use quote::{
+    format_ident,
+    quote,
+    ToTokens, //
+};
+use syn::{
+    parse_quote,
+    Error,
+    Ident,
+    Item,
+    ItemMod,
+    LitCStr,
+    Result, //
+};
+
+pub(crate) fn kunit_tests(test_suite: Ident, mut module: ItemMod) -> Result<TokenStream> {
+    if test_suite.to_string().len() > 255 {
+        return Err(Error::new_spanned(
+            test_suite,
+            "test suite names cannot exceed the maximum length of 255 bytes",
+        ));
+    }
+
+    // We cannot handle modules that defer to another file (e.g. `mod foo;`).
+    let Some((module_brace, module_items)) = module.content.take() else {
+        Err(Error::new_spanned(
+            module,
+            "`#[kunit_tests(test_name)]` attribute should only be applied to inline modules",
+        ))?
+    };
+
+    // Make the entire module gated behind `CONFIG_KUNIT`.
+    module
+        .attrs
+        .insert(0, parse_quote!(#[cfg(CONFIG_KUNIT="y")]));
+
+    let mut processed_items = Vec::new();
+    let mut test_cases = Vec::new();
+
+    // Generate the test KUnit test suite and a test case for each `#[test]`.
+    //
+    // The code generated for the following test module:
+    //
+    // ```
+    // #[kunit_tests(kunit_test_suit_name)]
+    // mod tests {
+    //     #[test]
+    //     fn foo() {
+    //         assert_eq!(1, 1);
+    //     }
+    //
+    //     #[test]
+    //     fn bar() {
+    //         assert_eq!(2, 2);
+    //     }
+    // }
+    // ```
+    //
+    // 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(); }
+    //
+    // static mut TEST_CASES: [::kernel::bindings::kunit_case; 3] = [
+    //     ::kernel::kunit::kunit_case(c"foo", kunit_rust_wrapper_foo),
+    //     ::kernel::kunit::kunit_case(c"bar", kunit_rust_wrapper_bar),
+    //     ::pin_init::zeroed(),
+    // ];
+    //
+    // ::kernel::kunit_unsafe_test_suite!(kunit_test_suit_name, TEST_CASES);
+    // ```
+    //
+    // Non-function items (e.g. imports) are preserved.
+    for item in module_items {
+        let Item::Fn(mut f) = item else {
+            processed_items.push(item);
+            continue;
+        };
+
+        if f.attrs
+            .extract_if(.., |attr| attr.path().is_ident("test"))
+            .count()
+            == 0
+        {
+            processed_items.push(Item::Fn(f));
+            continue;
+        }
+
+        let test = f.sig.ident.clone();
+
+        // Retrieve `#[cfg]` applied on the function which needs to be present on derived items too.
+        let cfg_attrs: Vec<_> = f
+            .attrs
+            .iter()
+            .filter(|attr| attr.path().is_ident("cfg"))
+            .cloned()
+            .collect();
+
+        // Before the test, override usual `assert!` and `assert_eq!` macros with ones that call
+        // KUnit instead.
+        let test_str = test.to_string();
+        let path = CString::new(crate::helpers::file()).expect("file path cannot contain NUL");
+        processed_items.push(parse_quote! {
+            #[allow(unused)]
+            macro_rules! assert {
+                ($cond:expr $(,)?) => {{
+                    kernel::kunit_assert!(#test_str, #path, 0, $cond);
+                }}
+            }
+        });
+        processed_items.push(parse_quote! {
+            #[allow(unused)]
+            macro_rules! assert_eq {
+                ($left:expr, $right:expr $(,)?) => {{
+                    kernel::kunit_assert_eq!(#test_str, #path, 0, $left, $right);
+                }}
+            }
+        });
+
+        // Add back the test item.
+        processed_items.push(Item::Fn(f));
+
+        let kunit_wrapper_fn_name = format_ident!("kunit_rust_wrapper_{test}");
+        let test_cstr = LitCStr::new(
+            &CString::new(test_str.as_str()).expect("identifier cannot contain NUL"),
+            test.span(),
+        );
+        processed_items.push(parse_quote! {
+            unsafe extern "C" fn #kunit_wrapper_fn_name(_test: *mut ::kernel::bindings::kunit) {
+                (*_test).status = ::kernel::bindings::kunit_status_KUNIT_SKIPPED;
+
+                // Append any `cfg` attributes the user might have written on their tests so we
+                // don't attempt to call them when they are `cfg`'d out. An extra `use` is used
+                // here to reduce the length of the assert message.
+                #(#cfg_attrs)*
+                {
+                    (*_test).status = ::kernel::bindings::kunit_status_KUNIT_SUCCESS;
+                    use ::kernel::kunit::is_test_result_ok;
+                    assert!(is_test_result_ok(#test()));
+                }
+            }
+        });
+
+        test_cases.push(quote!(
+            ::kernel::kunit::kunit_case(#test_cstr, #kunit_wrapper_fn_name)
+        ));
+    }
+
+    let num_tests_plus_1 = test_cases.len() + 1;
+    processed_items.push(parse_quote! {
+        static mut TEST_CASES: [::kernel::bindings::kunit_case; #num_tests_plus_1] = [
+            #(#test_cases,)*
+            ::pin_init::zeroed(),
+        ];
+    });
+    processed_items.push(parse_quote! {
+        ::kernel::kunit_unsafe_test_suite!(#test_suite, TEST_CASES);
+    });
+
+    module.content = Some((module_brace, processed_items));
+    Ok(module.to_token_stream())
+}
diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
new file mode 100644
index 000000000..24f96feae
--- /dev/null
+++ b/rust/macros/lib.rs
@@ -0,0 +1,539 @@
+// SPDX-License-Identifier: GPL-2.0
+
+//! Crate for all kernel procedural macros.
+
+// When fixdep scans this, it will find this string `CONFIG_RUSTC_VERSION_TEXT`
+// 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.
+#![cfg_attr(not(CONFIG_RUSTC_HAS_SPAN_FILE), feature(proc_macro_span))]
+
+mod concat_idents;
+mod export;
+mod fmt;
+mod for_lt;
+mod helpers;
+mod kunit;
+mod module;
+mod paste;
+mod vtable;
+
+use proc_macro::TokenStream;
+
+use syn::parse_macro_input;
+
+/// Declares a kernel module.
+///
+/// The `type` argument should be a type which implements the [`Module`]
+/// trait. Also accepts various forms of kernel metadata.
+///
+/// The `params` field describe module parameters. Each entry has the form
+///
+/// ```ignore
+/// parameter_name: type {
+///     default: default_value,
+///     description: "Description",
+/// }
+/// ```
+///
+/// `type` may be one of
+///
+/// - [`i8`]
+/// - [`u8`]
+/// - [`i8`]
+/// - [`u8`]
+/// - [`i16`]
+/// - [`u16`]
+/// - [`i32`]
+/// - [`u32`]
+/// - [`i64`]
+/// - [`u64`]
+/// - [`isize`]
+/// - [`usize`]
+/// - [`bool`]
+///
+/// C header: [`include/linux/moduleparam.h`](srctree/include/linux/moduleparam.h)
+///
+/// [`Module`]: ../kernel/trait.Module.html
+///
+/// # Examples
+///
+/// ```ignore
+/// use kernel::prelude::*;
+///
+/// module!{
+///     type: MyModule,
+///     name: "my_kernel_module",
+///     authors: ["Rust for Linux Contributors"],
+///     description: "My very own kernel module!",
+///     license: "GPL",
+///     alias: ["alternate_module_name"],
+///     params: {
+///         my_parameter: i64 {
+///             default: 1,
+///             description: "This parameter has a default of 1",
+///         },
+///     },
+/// }
+///
+/// struct MyModule(i32);
+///
+/// impl kernel::Module for MyModule {
+///     fn init(_module: &'static ThisModule) -> Result<Self> {
+///         let foo: i32 = 42;
+///         pr_info!("I contain:  {}\n", foo);
+///         pr_info!("i32 param is:  {}\n", module_parameters::my_parameter.read());
+///         Ok(Self(foo))
+///     }
+/// }
+/// # fn main() {}
+/// ```
+///
+/// ## Firmware
+///
+/// The following example shows how to declare a kernel module that needs
+/// to load binary firmware files. You need to specify the file names of
+/// the firmware in the `firmware` field. The information is embedded
+/// in the `modinfo` section of the kernel module. For example, a tool to
+/// build an initramfs uses this information to put the firmware files into
+/// the initramfs image.
+///
+/// ```
+/// use kernel::prelude::*;
+///
+/// module!{
+///     type: MyDeviceDriverModule,
+///     name: "my_device_driver_module",
+///     authors: ["Rust for Linux Contributors"],
+///     description: "My device driver requires firmware",
+///     license: "GPL",
+///     firmware: ["my_device_firmware1.bin", "my_device_firmware2.bin"],
+/// }
+///
+/// struct MyDeviceDriverModule;
+///
+/// impl kernel::Module for MyDeviceDriverModule {
+///     fn init(_module: &'static ThisModule) -> Result<Self> {
+///         Ok(Self)
+///     }
+/// }
+/// # fn main() {}
+/// ```
+///
+/// # Supported argument types
+///   - `type`: type which implements the [`Module`] trait (required).
+///   - `name`: ASCII string literal of the name of the kernel module (required).
+///   - `authors`: array of ASCII string literals of the authors of the kernel module.
+///   - `description`: string literal of the description of the kernel module.
+///   - `license`: ASCII string literal of the license of the kernel module (required).
+///   - `alias`: array of ASCII string literals of the alias names of the kernel module.
+///   - `firmware`: array of ASCII string literals of the firmware files of
+///     the kernel module.
+#[proc_macro]
+pub fn module(input: TokenStream) -> TokenStream {
+    module::module(parse_macro_input!(input))
+        .unwrap_or_else(|e| e.into_compile_error())
+        .into()
+}
+
+/// Declares or implements a vtable trait.
+///
+/// Linux's use of pure vtables is very close to Rust traits, but they differ
+/// in how unimplemented functions are represented. In Rust, traits can provide
+/// default implementation for all non-required methods (and the default
+/// implementation could just return `Error::EINVAL`); Linux typically use C
+/// `NULL` pointers to represent these functions.
+///
+/// This attribute closes that gap. A trait can be annotated with the
+/// `#[vtable]` attribute. Implementers of the trait will then also have to
+/// annotate the trait with `#[vtable]`. This attribute generates a `HAS_*`
+/// associated constant bool for each method in the trait that is set to true if
+/// the implementer has overridden the associated method.
+///
+/// For a trait method to be optional, it must have a default implementation.
+/// This is also the case for traits annotated with `#[vtable]`, but in this
+/// case the default implementation will never be executed. The reason for this
+/// is that the functions will be called through function pointers installed in
+/// C side vtables. When an optional method is not implemented on a `#[vtable]`
+/// trait, a `NULL` entry is installed in the vtable. Thus the default
+/// implementation is never called. Since these traits are not designed to be
+/// used on the Rust side, it should not be possible to call the default
+/// implementation. This is done to ensure that we call the vtable methods
+/// through the C vtable, and not through the Rust vtable. Therefore, the
+/// default implementation should call `build_error!`, which prevents
+/// calls to this function at compile time:
+///
+/// ```compile_fail
+/// # // Intentionally missing `use`s to simplify `rusttest`.
+/// build_error!(VTABLE_DEFAULT_ERROR)
+/// ```
+///
+/// Note that you might need to import [`kernel::error::VTABLE_DEFAULT_ERROR`].
+///
+/// This macro should not be used when all functions are required.
+///
+/// Additionally, this macro automatically handles the `OwnerModule`
+/// associated type: on the trait side, `type OwnerModule: ModuleMetadata;`
+/// is added as a required associated type if not already defined; on the
+/// impl side, `type OwnerModule = LocalModule;` is automatically inserted
+/// if not explicitly defined.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::error::VTABLE_DEFAULT_ERROR;
+/// use kernel::prelude::*;
+///
+/// # struct LocalModule;
+/// # impl kernel::ModuleMetadata for LocalModule {
+/// #     const NAME: &'static kernel::str::CStr = c"vtable_doctest";
+/// #
+/// #     // SAFETY: This doctest runs on the host: there is no `THIS_MODULE`.
+/// #     const THIS_MODULE: kernel::ThisModule = unsafe {
+/// #         kernel::ThisModule::from_ptr(core::ptr::null_mut())
+/// #     };
+/// # }
+/// #
+/// # fn main() {
+/// // Declares a `#[vtable]` trait
+/// #[vtable]
+/// pub trait Operations: Send + Sync + Sized {
+///     fn foo(&self) -> Result<()> {
+///         build_error!(VTABLE_DEFAULT_ERROR)
+///     }
+///
+///     fn bar(&self) -> Result<()> {
+///         build_error!(VTABLE_DEFAULT_ERROR)
+///     }
+/// }
+///
+/// struct Foo;
+///
+/// // Implements the `#[vtable]` trait
+/// #[vtable]
+/// impl Operations for Foo {
+///     fn foo(&self) -> Result<()> {
+/// #        Err(EINVAL)
+///         // ...
+///     }
+/// }
+///
+/// assert_eq!(<Foo as Operations>::HAS_FOO, true);
+/// assert_eq!(<Foo as Operations>::HAS_BAR, false);
+/// # }
+/// ```
+///
+/// [`kernel::error::VTABLE_DEFAULT_ERROR`]: ../kernel/error/constant.VTABLE_DEFAULT_ERROR.html
+#[proc_macro_attribute]
+pub fn vtable(attr: TokenStream, input: TokenStream) -> TokenStream {
+    parse_macro_input!(attr as syn::parse::Nothing);
+    vtable::vtable(parse_macro_input!(input))
+        .unwrap_or_else(|e| e.into_compile_error())
+        .into()
+}
+
+/// Export a function so that C code can call it via a header file.
+///
+/// Functions exported using this macro can be called from C code using the declaration in the
+/// appropriate header file. It should only be used in cases where C calls the function through a
+/// header file; cases where C calls into Rust via a function pointer in a vtable (such as
+/// `file_operations`) should not use this macro.
+///
+/// This macro has the following effect:
+///
+/// * Disables name mangling for this function.
+/// * Verifies at compile-time that the function signature matches the declaration in the header
+///   file.
+///
+/// You must declare the signature of the Rust function in a header file that is included by
+/// `rust/bindings/bindings_helper.h`.
+///
+/// This macro is *not* the same as the C macros `EXPORT_SYMBOL_*`. All Rust symbols are currently
+/// automatically exported with `EXPORT_SYMBOL_GPL`.
+#[proc_macro_attribute]
+pub fn export(attr: TokenStream, input: TokenStream) -> TokenStream {
+    parse_macro_input!(attr as syn::parse::Nothing);
+    export::export(parse_macro_input!(input)).into()
+}
+
+/// Like [`core::format_args!`], but automatically wraps arguments in [`kernel::fmt::Adapter`].
+///
+/// This macro allows generating `fmt::Arguments` while ensuring that each argument is wrapped with
+/// `::kernel::fmt::Adapter`, which customizes formatting behavior for kernel logging.
+///
+/// Named arguments used in the format string (e.g. `{foo}`) are detected and resolved from local
+/// bindings. All positional and named arguments are automatically wrapped.
+///
+/// This macro is an implementation detail of other kernel logging macros like [`pr_info!`] and
+/// should not typically be used directly.
+///
+/// [`kernel::fmt::Adapter`]: ../kernel/fmt/struct.Adapter.html
+/// [`pr_info!`]: ../kernel/macro.pr_info.html
+#[proc_macro]
+pub fn fmt(input: TokenStream) -> TokenStream {
+    fmt::fmt(input.into()).into()
+}
+
+/// Concatenate two identifiers.
+///
+/// This is useful in macros that need to declare or reference items with names
+/// starting with a fixed prefix and ending in a user specified name. The resulting
+/// identifier has the span of the second argument.
+///
+/// # Examples
+///
+/// ```
+/// # const binder_driver_return_protocol_BR_OK: u32 = 0;
+/// # const binder_driver_return_protocol_BR_ERROR: u32 = 1;
+/// # const binder_driver_return_protocol_BR_TRANSACTION: u32 = 2;
+/// # const binder_driver_return_protocol_BR_REPLY: u32 = 3;
+/// # const binder_driver_return_protocol_BR_DEAD_REPLY: u32 = 4;
+/// # const binder_driver_return_protocol_BR_TRANSACTION_COMPLETE: u32 = 5;
+/// # const binder_driver_return_protocol_BR_INCREFS: u32 = 6;
+/// # const binder_driver_return_protocol_BR_ACQUIRE: u32 = 7;
+/// # const binder_driver_return_protocol_BR_RELEASE: u32 = 8;
+/// # const binder_driver_return_protocol_BR_DECREFS: u32 = 9;
+/// # const binder_driver_return_protocol_BR_NOOP: u32 = 10;
+/// # const binder_driver_return_protocol_BR_SPAWN_LOOPER: u32 = 11;
+/// # const binder_driver_return_protocol_BR_DEAD_BINDER: u32 = 12;
+/// # const binder_driver_return_protocol_BR_CLEAR_DEATH_NOTIFICATION_DONE: u32 = 13;
+/// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
+/// use kernel::macros::concat_idents;
+///
+/// macro_rules! pub_no_prefix {
+///     ($prefix:ident, $($newname:ident),+) => {
+///         $(pub(crate) const $newname: u32 = concat_idents!($prefix, $newname);)+
+///     };
+/// }
+///
+/// pub_no_prefix!(
+///     binder_driver_return_protocol_,
+///     BR_OK,
+///     BR_ERROR,
+///     BR_TRANSACTION,
+///     BR_REPLY,
+///     BR_DEAD_REPLY,
+///     BR_TRANSACTION_COMPLETE,
+///     BR_INCREFS,
+///     BR_ACQUIRE,
+///     BR_RELEASE,
+///     BR_DECREFS,
+///     BR_NOOP,
+///     BR_SPAWN_LOOPER,
+///     BR_DEAD_BINDER,
+///     BR_CLEAR_DEATH_NOTIFICATION_DONE,
+///     BR_FAILED_REPLY
+/// );
+///
+/// assert_eq!(BR_OK, binder_driver_return_protocol_BR_OK);
+/// ```
+#[proc_macro]
+pub fn concat_idents(input: TokenStream) -> TokenStream {
+    concat_idents::concat_idents(parse_macro_input!(input)).into()
+}
+
+/// Paste identifiers together.
+///
+/// Within the `paste!` macro, identifiers inside `[<` and `>]` are concatenated together to form a
+/// single identifier.
+///
+/// This is similar to the [`paste`] crate, but with pasting feature limited to identifiers and
+/// literals (lifetimes and documentation strings are not supported). There is a difference in
+/// supported modifiers as well.
+///
+/// # Examples
+///
+/// ```
+/// # const binder_driver_return_protocol_BR_OK: u32 = 0;
+/// # const binder_driver_return_protocol_BR_ERROR: u32 = 1;
+/// # const binder_driver_return_protocol_BR_TRANSACTION: u32 = 2;
+/// # const binder_driver_return_protocol_BR_REPLY: u32 = 3;
+/// # const binder_driver_return_protocol_BR_DEAD_REPLY: u32 = 4;
+/// # const binder_driver_return_protocol_BR_TRANSACTION_COMPLETE: u32 = 5;
+/// # const binder_driver_return_protocol_BR_INCREFS: u32 = 6;
+/// # const binder_driver_return_protocol_BR_ACQUIRE: u32 = 7;
+/// # const binder_driver_return_protocol_BR_RELEASE: u32 = 8;
+/// # const binder_driver_return_protocol_BR_DECREFS: u32 = 9;
+/// # const binder_driver_return_protocol_BR_NOOP: u32 = 10;
+/// # const binder_driver_return_protocol_BR_SPAWN_LOOPER: u32 = 11;
+/// # const binder_driver_return_protocol_BR_DEAD_BINDER: u32 = 12;
+/// # const binder_driver_return_protocol_BR_CLEAR_DEATH_NOTIFICATION_DONE: u32 = 13;
+/// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
+/// macro_rules! pub_no_prefix {
+///     ($prefix:ident, $($newname:ident),+) => {
+///         ::kernel::macros::paste! {
+///             $(pub(crate) const $newname: u32 = [<$prefix $newname>];)+
+///         }
+///     };
+/// }
+///
+/// pub_no_prefix!(
+///     binder_driver_return_protocol_,
+///     BR_OK,
+///     BR_ERROR,
+///     BR_TRANSACTION,
+///     BR_REPLY,
+///     BR_DEAD_REPLY,
+///     BR_TRANSACTION_COMPLETE,
+///     BR_INCREFS,
+///     BR_ACQUIRE,
+///     BR_RELEASE,
+///     BR_DECREFS,
+///     BR_NOOP,
+///     BR_SPAWN_LOOPER,
+///     BR_DEAD_BINDER,
+///     BR_CLEAR_DEATH_NOTIFICATION_DONE,
+///     BR_FAILED_REPLY
+/// );
+///
+/// assert_eq!(BR_OK, binder_driver_return_protocol_BR_OK);
+/// ```
+///
+/// # Modifiers
+///
+/// For each identifier, it is possible to attach one or multiple modifiers to
+/// it.
+///
+/// Currently supported modifiers are:
+/// * `span`: change the span of concatenated identifier to the span of the specified token. By
+///   default the span of the `[< >]` group is used.
+/// * `lower`: change the identifier to lower case.
+/// * `upper`: change the identifier to upper case.
+///
+/// ```
+/// # const binder_driver_return_protocol_BR_OK: u32 = 0;
+/// # const binder_driver_return_protocol_BR_ERROR: u32 = 1;
+/// # const binder_driver_return_protocol_BR_TRANSACTION: u32 = 2;
+/// # const binder_driver_return_protocol_BR_REPLY: u32 = 3;
+/// # const binder_driver_return_protocol_BR_DEAD_REPLY: u32 = 4;
+/// # const binder_driver_return_protocol_BR_TRANSACTION_COMPLETE: u32 = 5;
+/// # const binder_driver_return_protocol_BR_INCREFS: u32 = 6;
+/// # const binder_driver_return_protocol_BR_ACQUIRE: u32 = 7;
+/// # const binder_driver_return_protocol_BR_RELEASE: u32 = 8;
+/// # const binder_driver_return_protocol_BR_DECREFS: u32 = 9;
+/// # const binder_driver_return_protocol_BR_NOOP: u32 = 10;
+/// # const binder_driver_return_protocol_BR_SPAWN_LOOPER: u32 = 11;
+/// # const binder_driver_return_protocol_BR_DEAD_BINDER: u32 = 12;
+/// # const binder_driver_return_protocol_BR_CLEAR_DEATH_NOTIFICATION_DONE: u32 = 13;
+/// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;
+/// macro_rules! pub_no_prefix {
+///     ($prefix:ident, $($newname:ident),+) => {
+///         ::kernel::macros::paste! {
+///             $(pub(crate) const fn [<$newname:lower:span>]() -> u32 { [<$prefix $newname:span>] })+
+///         }
+///     };
+/// }
+///
+/// pub_no_prefix!(
+///     binder_driver_return_protocol_,
+///     BR_OK,
+///     BR_ERROR,
+///     BR_TRANSACTION,
+///     BR_REPLY,
+///     BR_DEAD_REPLY,
+///     BR_TRANSACTION_COMPLETE,
+///     BR_INCREFS,
+///     BR_ACQUIRE,
+///     BR_RELEASE,
+///     BR_DECREFS,
+///     BR_NOOP,
+///     BR_SPAWN_LOOPER,
+///     BR_DEAD_BINDER,
+///     BR_CLEAR_DEATH_NOTIFICATION_DONE,
+///     BR_FAILED_REPLY
+/// );
+///
+/// assert_eq!(br_ok(), binder_driver_return_protocol_BR_OK);
+/// ```
+///
+/// # Literals
+///
+/// Literals can also be concatenated with other identifiers:
+///
+/// ```
+/// macro_rules! create_numbered_fn {
+///     ($name:literal, $val:literal) => {
+///         ::kernel::macros::paste! {
+///             fn [<some_ $name _fn $val>]() -> u32 { $val }
+///         }
+///     };
+/// }
+///
+/// create_numbered_fn!("foo", 100);
+///
+/// assert_eq!(some_foo_fn100(), 100)
+/// ```
+///
+/// [`paste`]: https://docs.rs/paste/
+#[proc_macro]
+pub fn paste(input: TokenStream) -> TokenStream {
+    let mut tokens = proc_macro2::TokenStream::from(input).into_iter().collect();
+    paste::expand(&mut tokens);
+    tokens
+        .into_iter()
+        .collect::<proc_macro2::TokenStream>()
+        .into()
+}
+
+/// Registers a KUnit test suite and its test cases using a user-space like syntax.
+///
+/// This macro should be used on modules. If `CONFIG_KUNIT` (in `.config`) is `n`, the target module
+/// is ignored.
+///
+/// # Examples
+///
+/// ```ignore
+/// # use kernel::prelude::*;
+/// #[kunit_tests(kunit_test_suit_name)]
+/// mod tests {
+///     #[test]
+///     fn foo() {
+///         assert_eq!(1, 1);
+///     }
+///
+///     #[test]
+///     fn bar() {
+///         assert_eq!(2, 2);
+///     }
+/// }
+/// ```
+#[proc_macro_attribute]
+pub fn kunit_tests(attr: TokenStream, input: TokenStream) -> TokenStream {
+    kunit::kunit_tests(parse_macro_input!(attr), parse_macro_input!(input))
+        .unwrap_or_else(|e| e.into_compile_error())
+        .into()
+}
+
+/// Obtain a type that implements [`ForLt`] for the given higher-ranked type.
+///
+/// Please refer to the documentation of the [`ForLt`] trait.
+///
+/// [`ForLt`]: trait.ForLt.html
+#[proc_macro]
+#[allow(non_snake_case)]
+pub fn ForLt(input: TokenStream) -> TokenStream {
+    for_lt::for_lt(parse_macro_input!(input)).into()
+}
+
+/// Obtain a type that implements [`CovariantForLt`] (and [`ForLt`]) for the given higher-ranked
+/// type.
+///
+/// Unlike [`ForLt!`], this macro additionally proves that the type is covariant over the lifetime,
+/// providing a safe [`CovariantForLt::cast_ref`] method.
+///
+/// Please refer to the documentation of the [`CovariantForLt`] trait.
+///
+/// [`CovariantForLt`]: trait.CovariantForLt.html
+/// [`CovariantForLt::cast_ref`]: trait.CovariantForLt.html#method.cast_ref
+/// [`ForLt`]: trait.ForLt.html
+#[proc_macro]
+#[allow(non_snake_case)]
+pub fn CovariantForLt(input: TokenStream) -> TokenStream {
+    for_lt::covariant_for_lt(parse_macro_input!(input)).into()
+}
diff --git a/rust/macros/module.rs b/rust/macros/module.rs
new file mode 100644
index 000000000..bc7027f8d
--- /dev/null
+++ b/rust/macros/module.rs
@@ -0,0 +1,654 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use std::ffi::CString;
+
+use proc_macro2::{
+    Literal,
+    TokenStream, //
+};
+use quote::{
+    format_ident,
+    quote, //
+};
+use syn::{
+    braced,
+    bracketed,
+    ext::IdentExt,
+    parse::{
+        Parse,
+        ParseStream, //
+    },
+    parse_quote,
+    punctuated::Punctuated,
+    Error,
+    Expr,
+    Ident,
+    LitStr,
+    Path,
+    Result,
+    Token,
+    Type, //
+};
+
+use crate::helpers::*;
+
+struct ModInfoBuilder<'a> {
+    module: &'a str,
+    counter: usize,
+    ts: TokenStream,
+    param_ts: TokenStream,
+}
+
+impl<'a> ModInfoBuilder<'a> {
+    fn new(module: &'a str) -> Self {
+        ModInfoBuilder {
+            module,
+            counter: 0,
+            ts: TokenStream::new(),
+            param_ts: TokenStream::new(),
+        }
+    }
+
+    fn emit_base(&mut self, field: &str, content: &str, builtin: bool, param: bool) {
+        let string = if builtin {
+            // Built-in modules prefix their modinfo strings by `module.`.
+            format!("{module}.{field}={content}\0", module = self.module)
+        } else {
+            // Loadable modules' modinfo strings go as-is.
+            format!("{field}={content}\0")
+        };
+        let length = string.len();
+        let string = Literal::byte_string(string.as_bytes());
+        let cfg = if builtin {
+            quote!(#[cfg(not(MODULE))])
+        } else {
+            quote!(#[cfg(MODULE)])
+        };
+
+        let counter = format_ident!(
+            "__{module}_{counter}",
+            module = self.module.to_uppercase(),
+            counter = self.counter
+        );
+        let item = quote! {
+            #cfg
+            #[cfg_attr(not(target_os = "macos"), link_section = ".modinfo")]
+            #[used(compiler)]
+            pub static #counter: [u8; #length] = *#string;
+        };
+
+        if param {
+            self.param_ts.extend(item);
+        } else {
+            self.ts.extend(item);
+        }
+
+        self.counter += 1;
+    }
+
+    fn emit_only_builtin(&mut self, field: &str, content: &str, param: bool) {
+        self.emit_base(field, content, true, param)
+    }
+
+    fn emit_only_loadable(&mut self, field: &str, content: &str, param: bool) {
+        self.emit_base(field, content, false, param)
+    }
+
+    fn emit(&mut self, field: &str, content: &str) {
+        self.emit_internal(field, content, false);
+    }
+
+    fn emit_internal(&mut self, field: &str, content: &str, param: bool) {
+        self.emit_only_builtin(field, content, param);
+        self.emit_only_loadable(field, content, param);
+    }
+
+    fn emit_param(&mut self, field: &str, param: &str, content: &str) {
+        let content = format!("{param}:{content}");
+        self.emit_internal(field, &content, true);
+    }
+
+    fn emit_params(&mut self, info: &ModuleInfo) {
+        let Some(params) = &info.params else {
+            return;
+        };
+
+        for param in params {
+            let param_name_str = param.name.to_string();
+            let param_type_str = param.ptype.to_string();
+
+            let ops = param_ops_path(&param_type_str);
+
+            // Note: The spelling of these fields is dictated by the user space
+            // tool `modinfo`.
+            self.emit_param("parmtype", &param_name_str, &param_type_str);
+            self.emit_param("parm", &param_name_str, &param.description.value());
+
+            let static_name = format_ident!("__{}_{}_struct", self.module, param.name);
+            let param_name_cstr =
+                CString::new(param_name_str).expect("name contains NUL-terminator");
+            let param_name_cstr_with_module =
+                CString::new(format!("{}.{}", self.module, param.name))
+                    .expect("name contains NUL-terminator");
+
+            let param_name = &param.name;
+            let param_type = &param.ptype;
+            let param_default = &param.default;
+
+            self.param_ts.extend(quote! {
+                #[allow(non_upper_case_globals)]
+                pub(crate) static #param_name:
+                    ::kernel::module_param::ModuleParamAccess<#param_type> =
+                        ::kernel::module_param::ModuleParamAccess::new(#param_default);
+
+                const _: () = {
+                    #[allow(non_upper_case_globals)]
+                    #[link_section = "__param"]
+                    #[used(compiler)]
+                    static #static_name:
+                        ::kernel::module_param::KernelParam =
+                        ::kernel::module_param::KernelParam::new(
+                            ::kernel::bindings::kernel_param {
+                                name: kernel::str::as_char_ptr_in_const_context(
+                                    if ::core::cfg!(MODULE) {
+                                        #param_name_cstr
+                                    } else {
+                                        #param_name_cstr_with_module
+                                    }
+                                ),
+                                // SAFETY: `__this_module` is constructed by the kernel at load
+                                // time and will not be freed until the module is unloaded.
+                                #[cfg(MODULE)]
+                                mod_: unsafe {
+                                    core::ptr::from_ref(&::kernel::bindings::__this_module)
+                                        .cast_mut()
+                                },
+                                #[cfg(not(MODULE))]
+                                mod_: ::core::ptr::null_mut(),
+                                ops: core::ptr::from_ref(&#ops),
+                                perm: 0, // Will not appear in sysfs
+                                level: -1,
+                                flags: 0,
+                                __bindgen_anon_1: ::kernel::bindings::kernel_param__bindgen_ty_1 {
+                                    arg: #param_name.as_void_ptr()
+                                },
+                            }
+                        );
+                };
+            });
+        }
+    }
+}
+
+fn param_ops_path(param_type: &str) -> Path {
+    match param_type {
+        "i8" => parse_quote!(::kernel::module_param::PARAM_OPS_I8),
+        "u8" => parse_quote!(::kernel::module_param::PARAM_OPS_U8),
+        "i16" => parse_quote!(::kernel::module_param::PARAM_OPS_I16),
+        "u16" => parse_quote!(::kernel::module_param::PARAM_OPS_U16),
+        "i32" => parse_quote!(::kernel::module_param::PARAM_OPS_I32),
+        "u32" => parse_quote!(::kernel::module_param::PARAM_OPS_U32),
+        "i64" => parse_quote!(::kernel::module_param::PARAM_OPS_I64),
+        "u64" => parse_quote!(::kernel::module_param::PARAM_OPS_U64),
+        "isize" => parse_quote!(::kernel::module_param::PARAM_OPS_ISIZE),
+        "usize" => parse_quote!(::kernel::module_param::PARAM_OPS_USIZE),
+        "bool" => parse_quote!(::kernel::module_param::PARAM_OPS_BOOL),
+        t => panic!("Unsupported parameter type {}", t),
+    }
+}
+
+/// Parse fields that are required to use a specific order.
+///
+/// As fields must follow a specific order, we *could* just parse fields one by one by peeking.
+/// However the error message generated when implementing that way is not very friendly.
+///
+/// So instead we parse fields in an arbitrary order, but only enforce the ordering after parsing,
+/// and if the wrong order is used, the proper order is communicated to the user with error message.
+///
+/// Usage looks like this:
+/// ```ignore
+/// parse_ordered_fields! {
+///     from input;
+///
+///     // This will extract "foo: <field>" into a variable named "foo".
+///     // The variable will have type `Option<_>`.
+///     foo => <expression that parses the field>,
+///
+///     // If you need the variable name to be different than the key name.
+///     // This extracts "baz: <field>" into a variable named "bar".
+///     // You might want this if "baz" is a keyword.
+///     baz as bar => <expression that parse the field>,
+///
+///     // You can mark a key as required, and the variable will no longer be `Option`.
+///     // foobar will be of type `Expr` instead of `Option<Expr>`.
+///     foobar [required] => input.parse::<Expr>()?,
+/// }
+/// ```
+macro_rules! parse_ordered_fields {
+    (@gen
+        [$input:expr]
+        [$([$name:ident; $key:ident; $parser:expr])*]
+        [$([$req_name:ident; $req_key:ident])*]
+    ) => {
+        $(let mut $name = None;)*
+
+        const EXPECTED_KEYS: &[&str] = &[$(stringify!($key),)*];
+        const REQUIRED_KEYS: &[&str] = &[$(stringify!($req_key),)*];
+
+        let span = $input.span();
+        let mut seen_keys = Vec::new();
+
+        while !$input.is_empty() {
+            let key = $input.call(Ident::parse_any)?;
+
+            if seen_keys.contains(&key) {
+                Err(Error::new_spanned(
+                    &key,
+                    format!(r#"duplicated key "{key}". Keys can only be specified once."#),
+                ))?
+            }
+
+            $input.parse::<Token![:]>()?;
+
+            match &*key.to_string() {
+                $(
+                    stringify!($key) => $name = Some($parser),
+                )*
+                _ => {
+                    Err(Error::new_spanned(
+                        &key,
+                        format!(r#"unknown key "{key}". Valid keys are: {EXPECTED_KEYS:?}."#),
+                    ))?
+                }
+            }
+
+            $input.parse::<Token![,]>()?;
+            seen_keys.push(key);
+        }
+
+        for key in REQUIRED_KEYS {
+            if !seen_keys.iter().any(|e| e == key) {
+                Err(Error::new(span, format!(r#"missing required key "{key}""#)))?
+            }
+        }
+
+        let mut ordered_keys: Vec<&str> = Vec::new();
+        for key in EXPECTED_KEYS {
+            if seen_keys.iter().any(|e| e == key) {
+                ordered_keys.push(key);
+            }
+        }
+
+        if seen_keys != ordered_keys {
+            Err(Error::new(
+                span,
+                format!(r#"keys are not ordered as expected. Order them like: {ordered_keys:?}."#),
+            ))?
+        }
+
+        $(let $req_name = $req_name.expect("required field");)*
+    };
+
+    // Handle required fields.
+    (@gen
+        [$input:expr] [$($tok:tt)*] [$($req:tt)*]
+        $key:ident as $name:ident [required] => $parser:expr,
+        $($rest:tt)*
+    ) => {
+        parse_ordered_fields!(
+            @gen [$input] [$($tok)* [$name; $key; $parser]] [$($req)* [$name; $key]] $($rest)*
+        )
+    };
+    (@gen
+        [$input:expr] [$($tok:tt)*] [$($req:tt)*]
+        $name:ident [required] => $parser:expr,
+        $($rest:tt)*
+    ) => {
+        parse_ordered_fields!(
+            @gen [$input] [$($tok)* [$name; $name; $parser]] [$($req)* [$name; $name]] $($rest)*
+        )
+    };
+
+    // Handle optional fields.
+    (@gen
+        [$input:expr] [$($tok:tt)*] [$($req:tt)*]
+        $key:ident as $name:ident => $parser:expr,
+        $($rest:tt)*
+    ) => {
+        parse_ordered_fields!(
+            @gen [$input] [$($tok)* [$name; $key; $parser]] [$($req)*] $($rest)*
+        )
+    };
+    (@gen
+        [$input:expr] [$($tok:tt)*] [$($req:tt)*]
+        $name:ident => $parser:expr,
+        $($rest:tt)*
+    ) => {
+        parse_ordered_fields!(
+            @gen [$input] [$($tok)* [$name; $name; $parser]] [$($req)*] $($rest)*
+        )
+    };
+
+    (from $input:expr; $($tok:tt)*) => {
+        parse_ordered_fields!(@gen [$input] [] [] $($tok)*)
+    }
+}
+
+struct Parameter {
+    name: Ident,
+    ptype: Ident,
+    default: Expr,
+    description: LitStr,
+}
+
+impl Parse for Parameter {
+    fn parse(input: ParseStream<'_>) -> Result<Self> {
+        let name = input.parse()?;
+        input.parse::<Token![:]>()?;
+        let ptype = input.parse()?;
+
+        let fields;
+        braced!(fields in input);
+
+        parse_ordered_fields! {
+            from fields;
+            default [required] => fields.parse()?,
+            description [required] => fields.parse()?,
+        }
+
+        Ok(Self {
+            name,
+            ptype,
+            default,
+            description,
+        })
+    }
+}
+
+pub(crate) struct ModuleInfo {
+    type_: Type,
+    license: AsciiLitStr,
+    name: AsciiLitStr,
+    authors: Option<Punctuated<AsciiLitStr, Token![,]>>,
+    description: Option<LitStr>,
+    alias: Option<Punctuated<AsciiLitStr, Token![,]>>,
+    firmware: Option<Punctuated<AsciiLitStr, Token![,]>>,
+    imports_ns: Option<Punctuated<AsciiLitStr, Token![,]>>,
+    params: Option<Punctuated<Parameter, Token![,]>>,
+}
+
+impl Parse for ModuleInfo {
+    fn parse(input: ParseStream<'_>) -> Result<Self> {
+        parse_ordered_fields!(
+            from input;
+            type as type_ [required] => input.parse()?,
+            name [required] => input.parse()?,
+            authors => {
+                let list;
+                bracketed!(list in input);
+                Punctuated::parse_terminated(&list)?
+            },
+            description => input.parse()?,
+            license [required] => input.parse()?,
+            alias => {
+                let list;
+                bracketed!(list in input);
+                Punctuated::parse_terminated(&list)?
+            },
+            firmware => {
+                let list;
+                bracketed!(list in input);
+                Punctuated::parse_terminated(&list)?
+            },
+            imports_ns => {
+                let list;
+                bracketed!(list in input);
+                Punctuated::parse_terminated(&list)?
+            },
+            params => {
+                let list;
+                braced!(list in input);
+                Punctuated::parse_terminated(&list)?
+            },
+        );
+
+        Ok(ModuleInfo {
+            type_,
+            license,
+            name,
+            authors,
+            description,
+            alias,
+            firmware,
+            imports_ns,
+            params,
+        })
+    }
+}
+
+pub(crate) fn module(info: ModuleInfo) -> Result<TokenStream> {
+    let ModuleInfo {
+        type_,
+        license,
+        name,
+        authors,
+        description,
+        alias,
+        firmware,
+        imports_ns,
+        params: _,
+    } = &info;
+
+    // Rust does not allow hyphens in identifiers, use underscore instead.
+    let ident = name.value().replace('-', "_");
+    let mut modinfo = ModInfoBuilder::new(ident.as_ref());
+    if let Some(authors) = authors {
+        for author in authors {
+            modinfo.emit("author", &author.value());
+        }
+    }
+    if let Some(description) = description {
+        modinfo.emit("description", &description.value());
+    }
+    modinfo.emit("license", &license.value());
+    if let Some(aliases) = alias {
+        for alias in aliases {
+            modinfo.emit("alias", &alias.value());
+        }
+    }
+    if let Some(firmware) = firmware {
+        for fw in firmware {
+            modinfo.emit("firmware", &fw.value());
+        }
+    }
+    if let Some(imports) = imports_ns {
+        for ns in imports {
+            modinfo.emit("import_ns", &ns.value());
+        }
+    }
+
+    // Built-in modules also export the `file` modinfo string.
+    let file =
+        std::env::var("RUST_MODFILE").expect("Unable to fetch RUST_MODFILE environmental variable");
+    modinfo.emit_only_builtin("file", &file, false);
+
+    modinfo.emit_params(&info);
+
+    let modinfo_ts = modinfo.ts;
+    let params_ts = modinfo.param_ts;
+
+    let ident_init = format_ident!("__{ident}_init");
+    let ident_exit = format_ident!("__{ident}_exit");
+    let ident_initcall = format_ident!("__{ident}_initcall");
+    let initcall_section = ".initcall6.init";
+
+    let global_asm = format!(
+        r#".section "{initcall_section}", "a"
+        __{ident}_initcall:
+            .long   __{ident}_init - .
+            .previous
+        "#
+    );
+
+    let name_cstr = CString::new(name.value()).expect("name contains NUL-terminator");
+
+    Ok(quote! {
+        /// The module name.
+        ///
+        /// Used by the printing macros, e.g. [`info!`].
+        const __LOG_PREFIX: &[u8] = #name_cstr.to_bytes_with_nul();
+
+        /// The `LocalModule` type is the type of the module created by `module!`,
+        /// `module_pci_driver!`, `module_platform_driver!`, etc.
+        type LocalModule = #type_;
+
+        impl ::kernel::ModuleMetadata for #type_ {
+            const NAME: &'static ::kernel::str::CStr = #name_cstr;
+
+            #[cfg(MODULE)]
+            const THIS_MODULE: ::kernel::ThisModule = {
+                extern "C" {
+                    static __this_module: ::kernel::types::Opaque<::kernel::bindings::module>;
+                }
+
+                // SAFETY: `__this_module` is constructed by the kernel at load time
+                // and lives until the module is unloaded.
+                unsafe { ::kernel::ThisModule::from_ptr(__this_module.get()) }
+            };
+
+            #[cfg(not(MODULE))]
+            const THIS_MODULE: ::kernel::ThisModule = unsafe {
+                ::kernel::ThisModule::from_ptr(::core::ptr::null_mut())
+            };
+        }
+
+        // Double nested modules, since then nobody can access the public items inside.
+        #[doc(hidden)]
+        mod __module_init {
+            mod __module_init {
+                use pin_init::PinInit;
+
+                /// The "Rust loadable module" mark.
+                //
+                // This may be best done another way later on, e.g. as a new modinfo
+                // key or a new section. For the moment, keep it simple.
+                #[cfg(MODULE)]
+                #[used(compiler)]
+                static __IS_RUST_MODULE: () = ();
+
+                static mut __MOD: ::core::mem::MaybeUninit<super::super::LocalModule> =
+                    ::core::mem::MaybeUninit::uninit();
+
+                // Loadable modules need to export the `{init,cleanup}_module` identifiers.
+                /// # Safety
+                ///
+                /// This function must not be called after module initialization, because it may be
+                /// freed after that completes.
+                #[cfg(MODULE)]
+                #[no_mangle]
+                #[link_section = ".init.text"]
+                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.
+                    unsafe { __init() }
+                }
+
+                #[cfg(MODULE)]
+                #[used(compiler)]
+                #[link_section = ".init.data"]
+                static __UNIQUE_ID___addressable_init_module: unsafe extern "C" fn() -> i32 =
+                    init_module;
+
+                #[cfg(MODULE)]
+                #[no_mangle]
+                #[link_section = ".exit.text"]
+                pub extern "C" fn cleanup_module() {
+                    // 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,
+                    // - furthermore it is only called after `init_module` has returned `0`
+                    //   (which delegates to `__init`).
+                    unsafe { __exit() }
+                }
+
+                #[cfg(MODULE)]
+                #[used(compiler)]
+                #[link_section = ".exit.data"]
+                static __UNIQUE_ID___addressable_cleanup_module: extern "C" fn() = cleanup_module;
+
+                // Built-in modules are initialized through an initcall pointer
+                // and the identifiers need to be unique.
+                #[cfg(not(MODULE))]
+                #[cfg(not(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS))]
+                #[link_section = #initcall_section]
+                #[used(compiler)]
+                pub static #ident_initcall: extern "C" fn() ->
+                    ::kernel::ffi::c_int = #ident_init;
+
+                #[cfg(not(MODULE))]
+                #[cfg(CONFIG_HAVE_ARCH_PREL32_RELOCATIONS)]
+                ::core::arch::global_asm!(#global_asm);
+
+                #[cfg(not(MODULE))]
+                #[no_mangle]
+                pub extern "C" fn #ident_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.
+                    unsafe { __init() }
+                }
+
+                #[cfg(not(MODULE))]
+                #[no_mangle]
+                pub extern "C" fn #ident_exit() {
+                    // 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,
+                    // - furthermore it is only called after `#ident_init` has
+                    //   returned `0` (which delegates to `__init`).
+                    unsafe { __exit() }
+                }
+
+                /// # Safety
+                ///
+                /// This function must only be called once.
+                unsafe fn __init() -> ::kernel::ffi::c_int {
+                    let initer = <super::super::LocalModule as ::kernel::InPlaceModule>::init(
+                        ::kernel::module::this_module::<super::super::LocalModule>()
+                    );
+                    // 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`.
+                    match unsafe { ::pin_init::raw_try_init(__MOD.as_mut_ptr(), initer) } {
+                        Ok(m) => 0,
+                        Err(e) => e.to_errno(),
+                    }
+                }
+
+                /// # Safety
+                ///
+                /// This function must
+                /// - only be called once,
+                /// - be called after `__init` has been called and returned `0`.
+                unsafe fn __exit() {
+                    // 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 `__init` was already called.
+                    unsafe {
+                        // Invokes `drop()` on `__MOD`, which should be used for cleanup.
+                        __MOD.assume_init_drop();
+                    }
+                }
+
+                #modinfo_ts
+            }
+        }
+
+        mod module_parameters {
+            #params_ts
+        }
+    })
+}
diff --git a/rust/macros/paste.rs b/rust/macros/paste.rs
new file mode 100644
index 000000000..2181e312a
--- /dev/null
+++ b/rust/macros/paste.rs
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use proc_macro2::{Delimiter, Group, Ident, Spacing, Span, TokenTree};
+
+fn concat_helper(tokens: &[TokenTree]) -> Vec<(String, Span)> {
+    let mut tokens = tokens.iter();
+    let mut segments = Vec::new();
+    let mut span = None;
+    loop {
+        match tokens.next() {
+            None => break,
+            Some(TokenTree::Literal(lit)) => {
+                // Allow us to concat string literals by stripping quotes
+                let mut value = lit.to_string();
+                if value.starts_with('"') && value.ends_with('"') {
+                    value.remove(0);
+                    value.pop();
+                }
+                segments.push((value, lit.span()));
+            }
+            Some(TokenTree::Ident(ident)) => {
+                let mut value = ident.to_string();
+                if value.starts_with("r#") {
+                    value.replace_range(0..2, "");
+                }
+                segments.push((value, ident.span()));
+            }
+            Some(TokenTree::Punct(p)) if p.as_char() == ':' => {
+                let Some(TokenTree::Ident(ident)) = tokens.next() else {
+                    panic!("expected identifier as modifier");
+                };
+
+                let (mut value, sp) = segments.pop().expect("expected identifier before modifier");
+                match ident.to_string().as_str() {
+                    // Set the overall span of concatenated token as current span
+                    "span" => {
+                        assert!(
+                            span.is_none(),
+                            "span modifier should only appear at most once"
+                        );
+                        span = Some(sp);
+                    }
+                    "lower" => value = value.to_lowercase(),
+                    "upper" => value = value.to_uppercase(),
+                    v => panic!("unknown modifier `{v}`"),
+                };
+                segments.push((value, sp));
+            }
+            Some(TokenTree::Group(group)) if group.delimiter() == Delimiter::None => {
+                let tokens = group.stream().into_iter().collect::<Vec<TokenTree>>();
+                segments.append(&mut concat_helper(tokens.as_slice()));
+            }
+            token => panic!("unexpected token in paste segments: {token:?}"),
+        };
+    }
+
+    segments
+}
+
+fn concat(tokens: &[TokenTree], group_span: Span) -> TokenTree {
+    let segments = concat_helper(tokens);
+    let pasted: String = segments.into_iter().map(|x| x.0).collect();
+    TokenTree::Ident(Ident::new(&pasted, group_span))
+}
+
+pub(crate) fn expand(tokens: &mut Vec<TokenTree>) {
+    for token in tokens.iter_mut() {
+        if let TokenTree::Group(group) = token {
+            let delimiter = group.delimiter();
+            let span = group.span();
+            let mut stream: Vec<_> = group.stream().into_iter().collect();
+            // Find groups that looks like `[< A B C D >]`
+            if delimiter == Delimiter::Bracket
+                && stream.len() >= 3
+                && matches!(&stream[0], TokenTree::Punct(p) if p.as_char() == '<')
+                && matches!(&stream[stream.len() - 1], TokenTree::Punct(p) if p.as_char() == '>')
+            {
+                // Replace the group with concatenated token
+                *token = concat(&stream[1..stream.len() - 1], span);
+            } else {
+                // Recursively expand tokens inside the group
+                expand(&mut stream);
+                let mut group = Group::new(delimiter, stream.into_iter().collect());
+                group.set_span(span);
+                *token = TokenTree::Group(group);
+            }
+        }
+    }
+
+    // Path segments cannot contain invisible delimiter group, so remove them if any.
+    for i in (0..tokens.len().saturating_sub(3)).rev() {
+        // Looking for a double colon
+        if matches!(
+            (&tokens[i + 1], &tokens[i + 2]),
+            (TokenTree::Punct(a), TokenTree::Punct(b))
+                if a.as_char() == ':' && a.spacing() == Spacing::Joint && b.as_char() == ':'
+        ) {
+            match &tokens[i + 3] {
+                TokenTree::Group(group) if group.delimiter() == Delimiter::None => {
+                    tokens.splice(i + 3..i + 4, group.stream());
+                }
+                _ => (),
+            }
+
+            match &tokens[i] {
+                TokenTree::Group(group) if group.delimiter() == Delimiter::None => {
+                    tokens.splice(i..i + 1, group.stream());
+                }
+                _ => (),
+            }
+        }
+    }
+}
diff --git a/rust/macros/vtable.rs b/rust/macros/vtable.rs
new file mode 100644
index 000000000..be9a5ed8a
--- /dev/null
+++ b/rust/macros/vtable.rs
@@ -0,0 +1,136 @@
+// SPDX-License-Identifier: GPL-2.0
+
+use std::{
+    collections::HashSet,
+    iter::Extend, //
+};
+
+use proc_macro2::{
+    Ident,
+    TokenStream, //
+};
+use quote::ToTokens;
+use syn::{
+    parse_quote,
+    Error,
+    ImplItem,
+    Item,
+    ItemImpl,
+    ItemTrait,
+    Result,
+    TraitItem, //
+};
+
+fn handle_trait(mut item: ItemTrait) -> Result<ItemTrait> {
+    let mut gen_items = Vec::new();
+
+    gen_items.push(parse_quote! {
+         /// A marker to prevent implementors from forgetting to use [`#[vtable]`](vtable)
+         /// attribute when implementing this trait.
+         const USE_VTABLE_ATTR: ();
+    });
+
+    // Add `type OwnerModule: ModuleMetadata` as a required associated type if
+    // the trait does not already define it.
+    if !item
+        .items
+        .iter()
+        .any(|i| matches!(i, TraitItem::Type(t) if t.ident == "OwnerModule"))
+    {
+        gen_items.push(parse_quote! {
+            /// The module implementing this vtable trait.
+            ///
+            /// Automatically set to `crate::LocalModule` by the `#[vtable]`
+            /// impl macro.
+            type OwnerModule: ::kernel::ModuleMetadata;
+        });
+    }
+
+    for item in &item.items {
+        if let TraitItem::Fn(fn_item) = item {
+            let name = &fn_item.sig.ident;
+            let gen_const_name = Ident::new(
+                &format!("HAS_{}", name.to_string().to_uppercase()),
+                name.span(),
+            );
+
+            // We don't know on the implementation-site whether a method is required or provided
+            // so we have to generate a const for all methods.
+            let cfg_attrs = crate::helpers::gather_cfg_attrs(&fn_item.attrs);
+            let comment =
+                format!("Indicates if the `{name}` method is overridden by the implementor.");
+            gen_items.push(parse_quote! {
+                #(#cfg_attrs)*
+                #[doc = #comment]
+                const #gen_const_name: bool = false;
+            });
+        }
+    }
+
+    item.items.extend(gen_items);
+    Ok(item)
+}
+
+fn handle_impl(mut item: ItemImpl) -> Result<ItemImpl> {
+    let mut gen_items = Vec::new();
+    let mut defined_items = HashSet::new();
+
+    // Iterate over all user-defined items to gather any possible explicit overrides.
+    for item in &item.items {
+        match item {
+            ImplItem::Const(const_item) => {
+                defined_items.insert(const_item.ident.clone());
+            }
+            ImplItem::Type(type_item) => {
+                defined_items.insert(type_item.ident.clone());
+            }
+            _ => {}
+        }
+    }
+
+    gen_items.push(parse_quote! {
+        const USE_VTABLE_ATTR: () = ();
+    });
+
+    // Auto-insert `type OwnerModule = crate::LocalModule` if not explicitly defined.
+    // `crate::LocalModule` resolves to the real module type (via `module!`) or a
+    // dummy fallback in non-module contexts (e.g., doctests).
+    if !defined_items.contains(&parse_quote!(OwnerModule)) {
+        gen_items.push(parse_quote! {
+            type OwnerModule = crate::LocalModule;
+        });
+    }
+
+    for item in &item.items {
+        if let ImplItem::Fn(fn_item) = item {
+            let name = &fn_item.sig.ident;
+            let gen_const_name = Ident::new(
+                &format!("HAS_{}", name.to_string().to_uppercase()),
+                name.span(),
+            );
+            // Skip if it's declared already -- this allows user override.
+            if defined_items.contains(&gen_const_name) {
+                continue;
+            }
+            let cfg_attrs = crate::helpers::gather_cfg_attrs(&fn_item.attrs);
+            gen_items.push(parse_quote! {
+                #(#cfg_attrs)*
+                const #gen_const_name: bool = true;
+            });
+        }
+    }
+
+    item.items.extend(gen_items);
+    Ok(item)
+}
+
+pub(crate) fn vtable(input: Item) -> Result<TokenStream> {
+    match input {
+        Item::Trait(item) => Ok(handle_trait(item)?.into_token_stream()),
+        Item::Impl(item) => Ok(handle_impl(item)?.into_token_stream()),
+        _ => Err(Error::new_spanned(
+            input,
+            "`#[vtable]` attribute should only be applied to trait or impl block",
+        ))?,
+    }
+}