diff options
Diffstat (limited to 'arch/x86/include/asm/text-patching.h')
| -rw-r--r-- | arch/x86/include/asm/text-patching.h | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h index e85ff65c43c3..05861cc08787 100644 --- a/arch/x86/include/asm/text-patching.h +++ b/arch/x86/include/asm/text-patching.h @@ -39,4 +39,32 @@ extern int poke_int3_handler(struct pt_regs *regs); extern void *text_poke_bp(void *addr, const void *opcode, size_t len, void *handler); extern int after_bootmem; +static inline void int3_emulate_jmp(struct pt_regs *regs, unsigned long ip) +{ + regs->ip = ip; +} + +#define INT3_INSN_SIZE 1 +#define CALL_INSN_SIZE 5 + +#ifdef CONFIG_X86_64 +static inline void int3_emulate_push(struct pt_regs *regs, unsigned long val) +{ + /* + * The int3 handler in entry_64.S adds a gap between the + * stack where the break point happened, and the saving of + * pt_regs. We can extend the original stack because of + * this gap. See the idtentry macro's create_gap option. + */ + regs->sp -= sizeof(unsigned long); + *(unsigned long *)regs->sp = val; +} + +static inline void int3_emulate_call(struct pt_regs *regs, unsigned long func) +{ + int3_emulate_push(regs, regs->ip - INT3_INSN_SIZE + CALL_INSN_SIZE); + int3_emulate_jmp(regs, func); +} +#endif + #endif /* _ASM_X86_TEXT_PATCHING_H */ |