From ae3d6978aa84f65376a790e23d3fb52fcc8346b2 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 18 Oct 2021 15:30:03 +0100 Subject: ARM: 9145/1: patch: fix BE32 compilation On BE32 kernels, the __opcode_to_mem_thumb32() interface is intentionally not defined, but it is referenced whenever runtime patching is enabled for the kernel, which may be for ftrace, jump label, kprobes or kgdb: arch/arm/kernel/patch.c: In function '__patch_text_real': arch/arm/kernel/patch.c:94:32: error: implicit declaration of function '__opcode_to_mem_thumb32' [-Werror=implicit-function-declaration] 94 | insn = __opcode_to_mem_thumb32(insn); | ^~~~~~~~~~~~~~~~~~~~~~~ Since BE32 kernels never run Thumb2 code, we never end up using the result of this call, so providing an extern declaration without a definition makes it build correctly. Reviewed-by: Linus Walleij Signed-off-by: Arnd Bergmann Signed-off-by: Russell King (Oracle) --- arch/arm/include/asm/opcodes.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'arch/arm/include/asm/opcodes.h') diff --git a/arch/arm/include/asm/opcodes.h b/arch/arm/include/asm/opcodes.h index 6bff94b2372b..38e3eabff5c3 100644 --- a/arch/arm/include/asm/opcodes.h +++ b/arch/arm/include/asm/opcodes.h @@ -110,12 +110,17 @@ extern asmlinkage unsigned int arm_check_condition(u32 opcode, u32 psr); #define __opcode_to_mem_thumb16(x) ___opcode_identity16(x) #define ___asm_opcode_to_mem_arm(x) ___asm_opcode_identity32(x) #define ___asm_opcode_to_mem_thumb16(x) ___asm_opcode_identity16(x) -#ifndef CONFIG_CPU_ENDIAN_BE32 +#ifdef CONFIG_CPU_ENDIAN_BE32 +#ifndef __ASSEMBLY__ /* * On BE32 systems, using 32-bit accesses to store Thumb instructions will not * work in all cases, due to alignment constraints. For now, a correct - * version is not provided for BE32. + * version is not provided for BE32, but the prototype needs to be there + * to compile patch.c. */ +extern __u32 __opcode_to_mem_thumb32(__u32); +#endif +#else #define __opcode_to_mem_thumb32(x) ___opcode_swahw32(x) #define ___asm_opcode_to_mem_thumb32(x) ___asm_opcode_swahw32(x) #endif -- cgit v1.2.3-59-g8ed1b