[CRIU] [PATCHv2 12/17] core/x86: add compatible 32 register set

Dmitry Safonov dsafonov at virtuozzo.com
Mon Apr 18 10:13:02 PDT 2016


On 04/18/2016 08:04 PM, Dmitry Safonov wrote:
> On 04/18/2016 08:01 PM, Dmitry Safonov wrote:
>> On 04/18/2016 01:32 PM, Pavel Emelyanov wrote:
>>> On 04/18/2016 01:24 PM, Dmitry Safonov wrote:
>>>> On 04/18/2016 01:17 PM, Pavel Emelyanov wrote:
>>>>> You cannot change field numbers in proto files w/o breaking backward
>>>>> compatibility.
>>>> Ok, so I will make gpregs_case the last member of
>>>> user_x86_regs_entry. Seems like, I also should make it
>>>> `optional`, so images made before could be read after
>>>> the patch. Right?
>>> Right.
>>>
>>> Or you can put the regs mode into message thread_info_x86. And make 
>>> it optional too.
>>
>> On the other hand, I may omit `optional` and use`required`
>> as gpregs will be inited with USER_X86_REGS_ENTRY__INIT,
>> filling it with zeros. And gpregs_case is 1 or 2, according
>> to proto enum.
>> So I may even make NATIVE = 0 and all will work as needed.
>> But I'm not sure, may I always expect this behavior?
>>
>
> Thinking about it some more: I will do it optional.
> As protobuf may binary expect required value to
> be in image and mess the things up.
> So, all I expected in previous mail was a claptrap.
>
Hehe, if RTFM earlier, I would have lesser questions.
Worth to add  this link (or quick notes from there):
https://developers.google.com/protocol-buffers/docs/proto#updating
to https://criu.org/Postulates or somewhere else?

-- 
Regards,
Dmitry Safonov



More information about the CRIU mailing list