[PATCH 0/8] x86: 5-level paging enabling for v4.12, Part 4

From: Kirill A. Shutemov
Date: Thu Apr 06 2017 - 10:01:54 EST


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