Re: [PATCH v16 05/22] KVM: Rename CONFIG_KVM_GENERIC_PRIVATE_MEM to CONFIG_HAVE_KVM_ARCH_GMEM_POPULATE

[Xiaoyao Li <xiaoyao.li@intel.com>]

On 7/25/2025 6:41 AM, Sean Christopherson wrote:
> On Wed, Jul 23, 2025, Xiaoyao Li wrote:
>> On 7/23/2025 6:46 PM, Fuad Tabba wrote:
>>> The original name was vague regarding its functionality. This Kconfig
>>> option specifically enables and gates the kvm_gmem_populate() function,
>>> which is responsible for populating a GPA range with guest data.
>>>
>>> The new name, HAVE_KVM_ARCH_GMEM_POPULATE, describes the purpose of the
>>> option: to enable arch-specific guest_memfd population mechanisms. It
>>> also follows the same pattern as the other HAVE_KVM_ARCH_* configuration
>>> options.
>>>
>>> This improves clarity for developers and ensures the name accurately
>>> reflects the functionality it controls, especially as guest_memfd
>>> support expands beyond purely "private" memory scenarios.
>>>
>>> Note that the vm type KVM_X86_SW_PROTECTED_VM does not need the populate
>>> function. Therefore, ensure that the correct configuration is selected
>>> when KVM_SW_PROTECTED_VM is enabled.
>>
>> the changelog needs to be enhanced. At least it doesn't talk about
>> KVM_X86_PRIVATE_MEM at all.
>>
>> If Sean is going to queue this version, I think he can help refine it when
>> queuing.
> 
> My bad, I simply forgot.  How's this?

looks good to me.

> --
> 
> The original name was vague regarding its functionality. This Kconfig
> option specifically enables and gates the kvm_gmem_populate() function,
> which is responsible for populating a GPA range with guest data.
> 
> The new name, HAVE_KVM_ARCH_GMEM_POPULATE, describes the purpose of the
> option: to enable arch-specific guest_memfd population mechanisms. It
> also follows the same pattern as the other HAVE_KVM_ARCH_* configuration
> options.
> 
> This improves clarity for developers and ensures the name accurately
> reflects the functionality it controls, especially as guest_memfd
> support expands beyond purely "private" memory scenarios.
> 
> Temporarily keep KVM_GENERIC_PRIVATE_MEM as an x86-only config so as to
> minimize the churn, and to hopefully make it easier to see what features
> require HAVE_KVM_ARCH_GMEM_POPULATE.  On that note, omit GMEM_POPULATE
> for KVM_X86_SW_PROTECTED_VM, as regular ol' memset() suffices for
> software-protected VMs.
> 
> As for KVM_GENERIC_PRIVATE_MEM, a future change will select KVM_GUEST_MEMFD
> for all 64-bit KVM builds, at which point the intermedidate config will
> become obsolete and can/will be dropped.
>