Re: [PATCH v4] arm64: mm: Populate vmemmap/linear at the page level for hotplugged sections

[Zhenhua Huang]

On 2025/1/8 18:11, Anshuman Khandual wrote:
> Just wondering why not start with PUD level itself ? Although SUBSECTION_SHIFT
> might never reach the PUD level but this will help keep the flags calculations
> bit simple and ready for all future changes.

I suppose that it's because these are significantly larger than 2M, 
whereas Catalin assumed SUBSECTION_SIZE would not increase?
His comment:
"should cover any changes to SUBSECTION_SHIFT making it *smaller* than 
2MB. "

> 	flags = 0;
>   	if (SUBSECTION_SHIFT < PUD_SHIFT)
>   		flags |= NO_PUD_BLOCK_MAPPINGS;
>   	if (SUBSECTION_SHIFT < CONT_PMD_SHIFT)
>   		flags |= NO_PMD_CONT_MAPPINGS;