Re: [PATCH v26 26/30] ELF: Introduce arch_setup_elf_property()

Yu, Yu-cheng
2021-05-20T21:06:39Z

On 5/20/2021 10:52 AM, Yu, Yu-cheng wrote:
> On 5/20/2021 10:38 AM, Matthew Wilcox wrote:
>> On Wed, May 19, 2021 at 03:14:58PM -0700, Yu, Yu-cheng wrote:
>>>>> +++ b/include/uapi/linux/elf.h
>>>>> @@ -455,4 +455,13 @@ typedef struct elf64_note {
>>>>>    /* Bits for GNU_PROPERTY_AARCH64_FEATURE_1_BTI */
>>>>>    #define GNU_PROPERTY_AARCH64_FEATURE_1_BTI    (1U << 0)
>>>>> +/* .note.gnu.property types for x86: */
>>>>> +#define GNU_PROPERTY_X86_FEATURE_1_AND        0xc0000002
>>>>
>>>> Why not 0xc0000001? ARM64 is 0xc0000000...
>>>>
>>>
>>> I just looked at the ABI document.
>>>
>>> ARM has GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
>>>
>>> X86 has:
>>>     GNU_PROPERTY_X86_ISA_1_USED    0xc0000000
>>>     GNU_PROPERTY_X86_ISA_1_NEEDED    0xc0000001
>>>     GNU_PROPERTY_X86_FEATURE_1_AND    0xc0000002
>>
>> Please add all three, not just the last one.
>>
>
> Ok!

Just found out, I have been reading an older version. Now 0xc0000000
and 0xc0000001 have become reserved/not-used. Maybe I will just put a
note about that along with the link to the ABI document.

Yu-cheng