From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- drivers/android/Kconfig | 65 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 drivers/android/Kconfig (limited to 'drivers/android/Kconfig') diff --git a/drivers/android/Kconfig b/drivers/android/Kconfig new file mode 100644 index 000000000..e2e402c9d --- /dev/null +++ b/drivers/android/Kconfig @@ -0,0 +1,65 @@ +# SPDX-License-Identifier: GPL-2.0 +menu "Android" + +config ANDROID_BINDER_IPC + bool "Android Binder IPC Driver" + depends on MMU + depends on NET + default n + help + Binder is used in Android for both communication between processes, + and remote method invocation. + + This means one Android process can call a method/routine in another + Android process, using Binder to identify, invoke and pass arguments + between said processes. + +config ANDROID_BINDER_IPC_RUST + bool "Rust version of Android Binder IPC Driver" + depends on RUST && MMU && !ANDROID_BINDER_IPC + help + This enables the Rust implementation of the Binder driver. + + Binder is used in Android for both communication between processes, + and remote method invocation. + + This means one Android process can call a method/routine in another + Android process, using Binder to identify, invoke and pass arguments + between said processes. + +config ANDROID_BINDERFS + bool "Android Binderfs filesystem" + depends on ANDROID_BINDER_IPC + default n + help + Binderfs is a pseudo-filesystem for the Android Binder IPC driver + which can be mounted per-ipc namespace allowing to run multiple + instances of Android. + Each binderfs mount initially only contains a binder-control device. + It can be used to dynamically allocate new binder IPC devices via + ioctls. + +config ANDROID_BINDER_DEVICES + string "Android Binder devices" + depends on ANDROID_BINDER_IPC || ANDROID_BINDER_IPC_RUST + default "binder,hwbinder,vndbinder" + help + Default value for the binder.devices parameter. + + The binder.devices parameter is a comma-separated list of strings + that specifies the names of the binder device nodes that will be + created. Each binder device has its own context manager, and is + therefore logically separated from the other devices. + +config ANDROID_BINDER_ALLOC_KUNIT_TEST + tristate "KUnit Tests for Android Binder Alloc" if !KUNIT_ALL_TESTS + depends on ANDROID_BINDER_IPC && KUNIT + default KUNIT_ALL_TESTS + help + This feature builds the binder alloc KUnit tests. + + Each test case runs using a pared-down binder_alloc struct and + test-specific freelist, which allows this KUnit module to be loaded + for testing without interfering with a running system. + +endmenu -- cgit v1.3.1