Re: [PATCH] x86: Unify cosmetic kprobes{32|64}.c

[Masami Hiramatsu <mhiramat@redhat.com>]

Hi Harvey,

Harvey Harrison wrote:
> diff --git a/arch/x86/kernel/kprobes_32.c b/arch/x86/kernel/kprobes_32.c
> index f4ba584..2a8acd6 100644
> --- a/arch/x86/kernel/kprobes_32.c
> +++ b/arch/x86/kernel/kprobes_32.c
> @@ -234,7 +234,7 @@ static int __kprobes is_IF_modifier(kprobe_opcode_t opcode)
>  
>  int __kprobes arch_prepare_kprobe(struct kprobe *p)
>  {
> -	/* insn: must be on special executable page on i386. */
> +	/* insn: must be on special executable page on x86_32|64. */
>  	p->ainsn.insn = get_insn_slot();
>  	if (!p->ainsn.insn)
>  		return -ENOMEM;
> @@ -373,13 +373,21 @@ static void __kprobes set_current_kprobe(struct kprobe *p, struct pt_regs *regs,
>  static __always_inline void clear_btf(void)
>  {
>  	if (test_thread_flag(TIF_DEBUGCTLMSR))
> +#ifdef CONFIG_X86_32
>  		wrmsr(MSR_IA32_DEBUGCTLMSR, 0, 0);
> +#else
> +		wrmsrl(MSR_IA32_DEBUGCTLMSR, 0);
> +#endif
>  }
>  
>  static __always_inline void restore_btf(void)
>  {
>  	if (test_thread_flag(TIF_DEBUGCTLMSR))
> +#ifdef CONFIG_X86_32
>  		wrmsr(MSR_IA32_DEBUGCTLMSR, current->thread.debugctlmsr, 0);
> +#else
> +		wrmsrl(MSR_IA32_DEBUGCTLMSR, current->thread.debugctlmsr);
> +#endif
>  }

I think you can use wrmsr() on X86_64 too.
So, we can merge it to wrmsr().


-- 
Masami Hiramatsu

Software Engineer
Hitachi Computer Products (America) Inc.
Software Solutions Division

e-mail: mhiramat@redhat.com, masami.hiramatsu.pt@hitachi.com