Re: [PATCH v3 1/3] arch/x86: Rename config X86_INTEL_MEMORY_PROTECTION_KEYS to generic x86

From: Babu Moger
Date: Tue May 12 2020 - 10:57:35 EST




On 5/11/20 6:44 PM, Dave Hansen wrote:
> On 5/11/20 4:32 PM, Babu Moger wrote:
>> AMD's next generation of EPYC processors support the MPK (Memory
>> Protection Keys) feature.
>>
>> So, rename X86_INTEL_MEMORY_PROTECTION_KEYS to X86_MEMORY_PROTECTION_KEYS.
>>
>> No functional changes.
>>
>> AMD documentation for MPK feature is available at "AMD64 Architecture
>> Programmerâs Manual Volume 2: System Programming, Pub. 24593 Rev. 3.34,
>> Section 5.6.6 Memory Protection Keys (MPK) Bit". Documentation can be
>> obtained at the link below.

I will remove this text. This is not too relevant here.

>
> I was hoping to see at least *some* justification in this changelog. Do
> you think having "INTEL_" will confuse users? Is there some technical
> merit to this change?
>
> The naming churn is an obviously bad, not technically necessary change.

Yes. Technically not necessary. But can cause some confusion on non-intel
platforms.

>
>> +config X86_MEMORY_PROTECTION_KEYS
>> + # Note: This is an intermediate change to avoid config prompt to
>> + # the users. Eventually, the option X86_INTEL_MEMORY_PROTECTION_KEYS
>> + # should be changed to X86_MEMORY_PROTECTION_KEYS permanently after
>> + # few kernel revisions.
>> + def_bool X86_INTEL_MEMORY_PROTECTION_KEYS
>
> "after a few kernel revisions" is code for "never". :)
>
> Could we put an explicit date on this, please? One year seems roughly
> right. Or, maybe "after the v5.10" release, so that this will approach
> will make into at least one LTS kernel.
>
> Maybe:
>
> # Set the "INTEL_"-free option whenever the "INTEL_" one is set.
> # The "INTEL_" one should be removed and replaced by this option after
> # 5.10. This avoids exposing most 'oldconfig' users to this churn.
>
Yes, this should work.