Here's the fourth and the last bunch of of patches that brings initial 5-level paging enabling. Please review and consider applying. As Ingo requested I've tried to rewrite assembly parts of boot process into C before bringing 5-level paging support. The only part where I succeed is startup_64 in arch/x86/kernel/head_64.S. Most of the logic is now in C. I failed to rewrite startup_32 in arch/x86/boot/compressed/head_64.S in C. The code I need to modify in still in 32-bit mode, but if I would move it to C it will be compiled as 64-bit. I've tried to move it into separate translation unit and compile it with -m32, but then linking phase fails due to type mismatch of object files. I also have trouble with rewriting secondary_startup_64. Stack breaks as soon as we switch to new page tables when onlining secondary CPUs. I don't know how to get around this. I hope it's not show-stopper. If you know how to get around these issues, let me know. Kirill A. Shutemov (8): x86/boot/64: Rewrite startup_64 in C x86/boot/64: Rename init_level4_pgt and early_level4_pgt x86/boot/64: Add support of additional page table level during early boot x86/mm: Add sync_global_pgds() for configuration with 5-level paging x86/mm: Make kernel_physical_mapping_init() support 5-level paging x86/mm: Add support for 5-level paging for KASLR x86: Enable 5-level paging support x86/mm: Allow to have userspace mappings above 47-bits arch/x86/Kconfig | 5 + arch/x86/boot/compressed/head_64.S | 23 ++++- arch/x86/include/asm/elf.h | 2 +- arch/x86/include/asm/mpx.h | 9 ++ arch/x86/include/asm/pgtable.h | 2 +- arch/x86/include/asm/pgtable_64.h | 6 +- arch/x86/include/asm/processor.h | 9 +- arch/x86/include/uapi/asm/processor-flags.h | 2 + arch/x86/kernel/espfix_64.c | 2 +- arch/x86/kernel/head64.c | 137 +++++++++++++++++++++++++--- arch/x86/kernel/head_64.S | 132 ++++++--------------------- arch/x86/kernel/machine_kexec_64.c | 2 +- arch/x86/kernel/sys_x86_64.c | 28 +++++- arch/x86/mm/dump_pagetables.c | 2 +- arch/x86/mm/hugetlbpage.c | 27 +++++- arch/x86/mm/init_64.c | 104 +++++++++++++++++++-- arch/x86/mm/kasan_init_64.c | 12 +-- arch/x86/mm/kaslr.c | 81 ++++++++++++---- arch/x86/mm/mmap.c | 2 +- arch/x86/mm/mpx.c | 33 ++++++- arch/x86/realmode/init.c | 2 +- arch/x86/xen/Kconfig | 1 + arch/x86/xen/mmu.c | 18 ++-- arch/x86/xen/xen-pvh.S | 2 +- 24 files changed, 463 insertions(+), 180 deletions(-) -- 2.11.0