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 --- arch/mips/mobileye/Kconfig | 29 +++++++++++++++++++++++++++++ arch/mips/mobileye/Makefile | 1 + arch/mips/mobileye/Platform | 17 +++++++++++++++++ arch/mips/mobileye/board-epm5.its.S | 24 ++++++++++++++++++++++++ arch/mips/mobileye/vmlinux.its.S | 32 ++++++++++++++++++++++++++++++++ 5 files changed, 103 insertions(+) create mode 100644 arch/mips/mobileye/Kconfig create mode 100644 arch/mips/mobileye/Makefile create mode 100644 arch/mips/mobileye/Platform create mode 100644 arch/mips/mobileye/board-epm5.its.S create mode 100644 arch/mips/mobileye/vmlinux.its.S (limited to 'arch/mips/mobileye') diff --git a/arch/mips/mobileye/Kconfig b/arch/mips/mobileye/Kconfig new file mode 100644 index 000000000..8a4868d2e --- /dev/null +++ b/arch/mips/mobileye/Kconfig @@ -0,0 +1,29 @@ +# SPDX-License-Identifier: GPL-2.0 +if EYEQ + +choice + prompt "Mobileye EyeQ SoC selection" + default MACH_EYEQ5 + help + Select Mobileye EyeQ MIPS SoC type. + + config MACH_EYEQ5 + bool "Mobileye EyeQ5 SoC" + + config MACH_EYEQ6H + bool "Mobileye EyeQ6H SoC" + + config MACH_EYEQ6LPLUS + bool "Mobileye EyeQ6Lplus SoC" +endchoice + +config FIT_IMAGE_FDT_EPM5 + bool "Include FDT for Mobileye EyeQ5 development platforms" + depends on MACH_EYEQ5 + default n + help + Enable this to include the FDT for the EyeQ5 development platforms + from Mobileye in the FIT kernel image. + This requires u-boot on the platform. + +endif diff --git a/arch/mips/mobileye/Makefile b/arch/mips/mobileye/Makefile new file mode 100644 index 000000000..315c06b68 --- /dev/null +++ b/arch/mips/mobileye/Makefile @@ -0,0 +1 @@ +# SPDX-License-Identifier: GPL-2.0-or-later diff --git a/arch/mips/mobileye/Platform b/arch/mips/mobileye/Platform new file mode 100644 index 000000000..93b533492 --- /dev/null +++ b/arch/mips/mobileye/Platform @@ -0,0 +1,17 @@ +# +# Copyright (C) 2016 Imagination Technologies +# Author: Paul Burton +# +# This program is free software; you can redistribute it and/or modify it +# under the terms of the GNU General Public License as published by the +# Free Software Foundation; either version 2 of the License, or (at your +# option) any later version. +# + +load-$(CONFIG_MACH_EYEQ5) = 0xa800000808000000 +load-$(CONFIG_MACH_EYEQ6H) = 0xa800000100800000 +load-$(CONFIG_MACH_EYEQ6LPLUS) = 0xa800000108800000 +all-$(CONFIG_MACH_EYEQ5) += vmlinux.gz.itb + +its-y := vmlinux.its.S +its-$(CONFIG_FIT_IMAGE_FDT_EPM5) += board-epm5.its.S diff --git a/arch/mips/mobileye/board-epm5.its.S b/arch/mips/mobileye/board-epm5.its.S new file mode 100644 index 000000000..08e8c4f18 --- /dev/null +++ b/arch/mips/mobileye/board-epm5.its.S @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */ +/ { + images { + fdt-mobileye-epm5 { + description = "Mobileeye MP5 Device Tree"; + data = /incbin/("boot/dts/mobileye/eyeq5-epm5.dtb"); + type = "flat_dt"; + arch = "mips"; + compression = "none"; + hash { + algo = "sha1"; + }; + }; + }; + + configurations { + default = "conf-1"; + conf-1 { + description = "Mobileye EPM5 Linux kernel"; + kernel = "kernel"; + fdt = "fdt-mobileye-epm5"; + }; + }; +}; diff --git a/arch/mips/mobileye/vmlinux.its.S b/arch/mips/mobileye/vmlinux.its.S new file mode 100644 index 000000000..3e2546765 --- /dev/null +++ b/arch/mips/mobileye/vmlinux.its.S @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/dts-v1/; + +/ { + description = KERNEL_NAME; + #address-cells = ; + + images { + kernel { + description = KERNEL_NAME; + data = /incbin/(VMLINUX_BINARY); + type = "kernel"; + arch = "mips"; + os = "linux"; + compression = VMLINUX_COMPRESSION; + load = /bits/ ADDR_BITS ; + entry = /bits/ ADDR_BITS ; + hash { + algo = "sha1"; + }; + }; + }; + + configurations { + default = "conf-default"; + + conf-default { + description = "Generic Linux kernel"; + kernel = "kernel"; + }; + }; +}; -- cgit v1.3.1