From 8dd47741d191400c46173ed9fba9d14b4033ce23 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 21 Jun 2010 15:10:37 +0100 Subject: [PATCH] ARM: 6189/1: Add support for the MOVW/MOVT relocations in Thumb-2 The patch adds handling case for the R_ARM_THM_MOVW_ABS_NC and R_ARM_THM_MOVT_ABS relocations in arch/arm/kernel/module.c. Such relocations may appear in Thumb-2 compiled kernel modules. Reported-by: Kyungmin Park Signed-off-by: Catalin Marinas Signed-off-by: Russell King --- arch/arm/include/asm/elf.h | 2 ++ arch/arm/kernel/module.c | 32 ++++++++++++++++++++++++++++++++ 2 files changed, 34 insertions(+) diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h index 6750b8e..5747a8b 100644 --- a/arch/arm/include/asm/elf.h +++ b/arch/arm/include/asm/elf.h @@ -59,6 +59,8 @@ typedef struct user_fp elf_fpregset_t; #define R_ARM_THM_CALL 10 #define R_ARM_THM_JUMP24 30 +#define R_ARM_THM_MOVW_ABS_NC 47 +#define R_ARM_THM_MOVT_ABS 48 /* * These are used to set parameters in the core dumps. diff --git a/arch/arm/kernel/module.c b/arch/arm/kernel/module.c index c628bdf..ae3c804 100644 --- a/arch/arm/kernel/module.c +++ b/arch/arm/kernel/module.c @@ -237,6 +237,38 @@ apply_relocate(Elf32_Shdr *sechdrs, const char *strtab, unsigned int symindex, lower = *(u16 *)(loc + 2); break; + case R_ARM_THM_MOVW_ABS_NC: + case R_ARM_THM_MOVT_ABS: + upper = *(u16 *)loc; + lower = *(u16 *)(loc + 2); + + /* + * MOVT/MOVW instructions encoding in Thumb-2: + * + * i = upper[10] + * imm4 = upper[3:0] + * imm3 = lower[14:12] + * imm8 = lower[7:0] + * + * imm16 = imm4:i:imm3:imm8 + */ + offset = ((upper & 0x000f) << 12) | + ((upper & 0x0400) << 1) | + ((lower & 0x7000) >> 4) | (lower & 0x00ff); + offset = (offset ^ 0x8000) - 0x8000; + offset += sym->st_value; + + if (ELF32_R_TYPE(rel->r_info) == R_ARM_THM_MOVT_ABS) + offset >>= 16; + + *(u16 *)loc = (u16)((upper & 0xfbf0) | + ((offset & 0xf000) >> 12) | + ((offset & 0x0800) >> 1)); + *(u16 *)(loc + 2) = (u16)((lower & 0x8f00) | + ((offset & 0x0700) << 4) | + (offset & 0x00ff)); + break; + default: printk(KERN_ERR "%s: unknown relocation: %u\n", module->name, ELF32_R_TYPE(rel->r_info)); -- 2.7.4