Re: [PATCHv4 09/14] x86/mm: Handle boot-time paging mode switching at early boot

* Kirill A. Shutemov wrote: > This patch adds detection of 5-level paging at boot-time and adjusts > virtual memory layout and folds p4d page table layer if needed. > > We have to make X86_5LEVEL dependant on SPARSEMEM_VMEMMAP. > !SPARSEMEM_VMEMMAP configuration doesn't work well with variable

Re: [PATCHv4 09/14] x86/mm: Handle boot-time paging mode switching at early boot

* Kirill A. Shutemov wrote: > /* Prepare to add new identity pagetables on demand. */ > diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S > index daf8936d0628..077e8b45784c 100644 > --- a/arch/x86/entry/entry_64.S > +++ b/arch/x86/entry/entry_64.S > @@ -273,8 +273,20 @@ re

[PATCHv4 09/14] x86/mm: Handle boot-time paging mode switching at early boot

This patch adds detection of 5-level paging at boot-time and adjusts virtual memory layout and folds p4d page table layer if needed. We have to make X86_5LEVEL dependant on SPARSEMEM_VMEMMAP. !SPARSEMEM_VMEMMAP configuration doesn't work well with variable MAX_PHYSMEM_BITS. Signed-off-by: Kirill