For some architectures, such as X86_64, ARCH_KMALLOC_MINALIGN is not resolvable for bindgen. E.g. due to being defined as __alignof__(unsigned long long). Hence, we have to create a rust helper, i.e. let the C compiler evaluate the expression and store it in a const. However, if for other architectures, such as arm64, ARCH_KMALLOC_MINALIGN does evaluate to something that can be directly processed by bindgen, we end up with multiple definitions of ARCH_KMALLOC_MINALIGN in the generated bindings. error[E0428]: the name `ARCH_KMALLOC_MINALIGN` is defined multiple times --> /builddir/build/BUILD/kernel-6.17.0-build/kernel-next-20250818/linux-6.17.0-0.0.next.20250818.423.vanilla.fc44.aarch64/rust/bindings/bindings_generated.rs:134545:1 | 9622 | pub const ARCH_KMALLOC_MINALIGN: u32 = 8; | ----------------------------------------- previous definition of the value `ARCH_KMALLOC_MINALIGN` here ... 134545 | pub const ARCH_KMALLOC_MINALIGN: usize = 8; | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `ARCH_KMALLOC_MINALIGN` redefined here | = note: `ARCH_KMALLOC_MINALIGN` must be defined only once in the value namespace of this module To fix this up, add ARCH_KMALLOC_MINALIGN to the blocklist of bindgen, such that we always only generate the symbol from the rust helper. Reported-by: Thorsten Leemhuis Closes: https://lore.kernel.org/all/8aa05f08-ef6e-4dfe-9453-beaab7b3cb98@leemhuis.info/ Fixes: 1b1a946dc2b5 ("rust: alloc: specify the minimum alignment of each allocator") Signed-off-by: Danilo Krummrich --- rust/bindgen_parameters | 1 + 1 file changed, 1 insertion(+) diff --git a/rust/bindgen_parameters b/rust/bindgen_parameters index 0f96af8b9a7f..02b371b98b39 100644 --- a/rust/bindgen_parameters +++ b/rust/bindgen_parameters @@ -34,3 +34,4 @@ # We use const helpers to aid bindgen, to avoid conflicts when constants are # recognized, block generation of the non-helper constants. --blocklist-item ARCH_SLAB_MINALIGN +--blocklist-item ARCH_KMALLOC_MINALIGN base-commit: 7e25d84f460c59322bf01dfeb1fb4745b488f714 -- 2.50.1