[v2 4/5] mm: zero struct pages during initialization

When deferred struct page initialization is enabled, do not expect that the memory that was allocated for struct pages was zeroed by the allocator. Zero it when "struct pages" are initialized. Also, a defined boolean VMEMMAP_ZERO is provided to tell platforms whether they should zero memory or

[v2 4/5] mm: zero struct pages during initialization

When deferred struct page initialization is enabled, do not expect that the memory that was allocated for struct pages was zeroed by the allocator. Zero it when "struct pages" are initialized. Also, a defined boolean VMEMMAP_ZERO is provided to tell platforms whether they should zero memory or