Re: [PATCH v6 22/36] nds32: Debugging support

[Vincent Chen]

2018-01-18 18:37 GMT+08:00 Arnd Bergmann <arnd@xxxxxxxx>:
> On Mon, Jan 15, 2018 at 6:53 AM, Greentime Hu <green.hu@xxxxxxxxx> wrote:
>> From: Greentime Hu <greentime@xxxxxxxxxxxxx>
>>
>> This patch adds ptrace support.
>>
>> Signed-off-by: Vincent Chen <vincentc@xxxxxxxxxxxxx>
>> Signed-off-by: Greentime Hu <greentime@xxxxxxxxxxxxx>
>
> I must have missed this patch earlier, unfortunately I don't think
> this is ready:
>
>> +long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
>> +                unsigned long data)
>> +{
>> +       int ret;
>> +
>> +       switch (request) {
>> +       case PTRACE_PEEKUSR:
>> +               ret =
>> +                   ptrace_read_user(child, addr, (unsigned long __user *)data);
>> +               break;
>> +
>> +       case PTRACE_POKEUSR:
>> +               ret = ptrace_write_user(child, addr, data);
>> +               break;
>> +
>> +       case PTRACE_GETREGS:
>> +               ret = ptrace_getregs(child, (void __user *)data);
>> +               break;
>> +
>> +       case PTRACE_SETREGS:
>> +               ret = ptrace_setregs(child, (void __user *)data);
>> +               break;
>> +
>> +       case PTRACE_GETFPREGS:
>> +               ret = ptrace_getfpregs(child, (void __user *)data);
>> +               break;
>> +
>> +       case PTRACE_SETFPREGS:
>> +               ret = ptrace_setfpregs(child, (void __user *)data);
>> +               break;
>> +
>> +       default:
>> +               ret = ptrace_request(child, request, addr, data);
>> +               break;
>> +       }
>> +
>> +       return ret;
>> +}
>
> It appears that you are implementing the old-style ptrace handling
> with architecture specific commands. Please have a look at how
> this is done in risc-v or arm64. If this takes more too much time
> to address, I'd suggest using an empty stub function for sys_ptrace
> and adding it back at a later point, but not send the current version
> upstream.
>
>      Arnd

Dear Arnd:

Thanks for your comments.

After referring to risc-v and arm64, I realize that PTRACE_GETREGSET
and PTRACE_SETREGSET is used to replace arch specific command.
The needed port for the two ptrace commands had done in current
version patch.

Could I keep them and just removing the code for old-style ptrace
handling in the next version patch?

Thanks

Vincent