* Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> 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 > MAX_PHYSMEM_BITS. > > Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> > --- > arch/x86/Kconfig | 1 + > arch/x86/boot/compressed/kaslr.c | 13 +++++-- > arch/x86/entry/entry_64.S | 12 +++++++ > arch/x86/include/asm/page_64_types.h | 13 +++---- > arch/x86/include/asm/pgtable_64_types.h | 35 +++++++++++-------- > arch/x86/include/asm/processor.h | 2 +- > arch/x86/include/asm/sparsemem.h | 9 ++--- > arch/x86/kernel/head64.c | 60 ++++++++++++++++++++++++++------- > arch/x86/kernel/head_64.S | 18 ++++++---- > arch/x86/kernel/setup.c | 5 ++- > arch/x86/mm/dump_pagetables.c | 8 +++-- > arch/x86/mm/kaslr.c | 13 ++++--- > 12 files changed, 129 insertions(+), 60 deletions(-) Please also split this patch up some more, into as many individual (but bisectable) changes as possible. > diff --git a/arch/x86/include/asm/sparsemem.h b/arch/x86/include/asm/sparsemem.h > index 1f5bee2c202f..ba67afd870b7 100644 > --- a/arch/x86/include/asm/sparsemem.h > +++ b/arch/x86/include/asm/sparsemem.h > @@ -26,13 +26,8 @@ > # endif > #else /* CONFIG_X86_32 */ > # define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */ > -# ifdef CONFIG_X86_5LEVEL > -# define MAX_PHYSADDR_BITS 52 > -# define MAX_PHYSMEM_BITS 52 > -# else > -# define MAX_PHYSADDR_BITS 44 > -# define MAX_PHYSMEM_BITS 46 > -# endif > +# define MAX_PHYSADDR_BITS (p4d_folded ? 44 : 52) > +# define MAX_PHYSMEM_BITS (p4d_folded ? 46 : 52) > #endif The kernel code size impact of these de-constification changes should be measured, double checked and documented as well. We are adding all kinds of overhead to (what I expect to be) commonly used kernels, let's do it carefully. Thanks, Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
