From: Alice Ryhl Date: Mon, 18 Nov 2024 20:27:26 +0000 (+0000) Subject: jump_label: rust: pass a mut ptr to `static_key_count` X-Git-Url: https://repo.jachan.dev/J-linux.git/commitdiff_plain/7643155dce1428fd63e47d7afe8bf3dbca20cc25 jump_label: rust: pass a mut ptr to `static_key_count` When building the rust_print sample with CONFIG_JUMP_LABEL=n, the Rust static key support falls back to using static_key_count. This function accepts a mutable pointer to the `struct static_key`, but the Rust abstractions are incorrectly passing a const pointer. This means that builds using CONFIG_JUMP_LABEL=n and SAMPLE_RUST_PRINT=y fail with the following error message: error[E0308]: mismatched types --> /samples/rust/rust_print_main.rs:87:5 | 87 | / kernel::declare_trace! { 88 | | /// # Safety 89 | | /// 90 | | /// Always safe to call. 91 | | unsafe fn rust_sample_loaded(magic: c_int); 92 | | } | | ^ | | | | |_____types differ in mutability | arguments to this function are incorrect | = note: expected raw pointer `*mut kernel::bindings::static_key` found raw pointer `*const kernel::bindings::static_key` note: function defined here --> /rust/bindings/bindings_helpers_generated.rs:33:12 | 33 | pub fn static_key_count(key: *mut static_key) -> c_int; | ^^^^^^^^^^^^^^^^ To fix this, insert a pointer cast so that the pointer is mutable. Link: https://lore.kernel.org/20241118202727.73646-1-aliceryhl@google.com Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202411181440.qEdcuyh6-lkp@intel.com/ Fixes: 169484ab6677 ("rust: add arch_static_branch") Signed-off-by: Alice Ryhl Acked-by: Miguel Ojeda Signed-off-by: Steven Rostedt (Google) --- diff --git a/rust/kernel/jump_label.rs b/rust/kernel/jump_label.rs index 2f2df03a3275..b5aff632ecc7 100644 --- a/rust/kernel/jump_label.rs +++ b/rust/kernel/jump_label.rs @@ -26,7 +26,7 @@ macro_rules! static_branch_unlikely { #[cfg(not(CONFIG_JUMP_LABEL))] { - $crate::bindings::static_key_count(_key) > 0 + $crate::bindings::static_key_count(_key.cast_mut()) > 0 } #[cfg(CONFIG_JUMP_LABEL)]