Re: PATCH: Enable x86 XML target descriptions

H.J. Lu
2010-02-22T22:21:31Z

On Mon, Feb 22, 2010 at 2:13 PM, H. Peter Anvin <hpa@zytor.com> wrote:
> On 02/22/2010 02:07 PM, H.J. Lu wrote:
>>
>> Oops. Wrong kernel source. The idea is the same. It is the CS.L bit
>> for 64-bit mode. That is
>>
>>   /* Value of CS register:
>>      1. 64bit: 0x33.
>>      2. 32bit: 0x23.
>>    */
>>
>
> That's not the CS.L bit; that's the selector value (which is currently
> the only thing exported.)  The future extension should export the
> descriptor information instead of relying on fixed values.
>

Yes, for the time being, gdb checks CS value before the new
ptrace option is added to kernel. After that, gdb will be changed
to check the the CS.L bit first and fail back to CS value.

--
H.J.