patches/kernel/0237-x86-mm-Map-cpu_entry_area-at-the-same-place-on-4-5-l.patch

   1 From 596ad95567b9dedff8b9f43b5ae18b1e3463da6b Mon Sep 17 00:00:00 2001
   2 From: Thomas Gleixner <tglx@linutronix.de>
   3 Date: Thu, 4 Jan 2018 13:01:40 +0100
   4 Subject: [PATCH 237/241] x86/mm: Map cpu_entry_area at the same place on 4/5
   5  level
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 commit f2078904810373211fb15f91888fba14c01a4acc upstream.
  11
  12 There is no reason for 4 and 5 level pagetables to have a different
  13 layout. It just makes determining vaddr_end for KASLR harder than
  14 necessary.
  15
  16 Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap")
  17 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  18 Cc: Andy Lutomirski <luto@kernel.org>
  19 Cc: Benjamin Gilbert <benjamin.gilbert@coreos.com>
  20 Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  21 Cc: Dave Hansen <dave.hansen@linux.intel.com>
  22 Cc: Peter Zijlstra <peterz@infradead.org>
  23 Cc: Thomas Garnier <thgarnie@google.com>,
  24 Cc: Alexander Kuleshov <kuleshovmail@gmail.com>
  25 Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801041320360.1771@nanos
  26 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  27 Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
  28 ---
  29  Documentation/x86/x86_64/mm.txt         | 7 ++++---
  30  arch/x86/include/asm/pgtable_64_types.h | 4 ++--
  31  arch/x86/mm/dump_pagetables.c           | 2 +-
  32  3 files changed, 7 insertions(+), 6 deletions(-)
  33
  34 diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt
  35 index ddd5ffd31bd0..f7dabe1f01e9 100644
  36 --- a/Documentation/x86/x86_64/mm.txt
  37 +++ b/Documentation/x86/x86_64/mm.txt
  38 @@ -12,8 +12,8 @@ ffffea0000000000 - ffffeaffffffffff (=40 bits) virtual memory map (1TB)
  39  ... unused hole ...
  40  ffffec0000000000 - fffffbffffffffff (=44 bits) kasan shadow memory (16TB)
  41  ... unused hole ...
  42 -fffffe0000000000 - fffffe7fffffffff (=39 bits) LDT remap for PTI
  43 -fffffe8000000000 - fffffeffffffffff (=39 bits) cpu_entry_area mapping
  44 +fffffe0000000000 - fffffe7fffffffff (=39 bits) cpu_entry_area mapping
  45 +fffffe8000000000 - fffffeffffffffff (=39 bits) LDT remap for PTI
  46  ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks
  47  ... unused hole ...
  48  ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space
  49 @@ -37,7 +37,8 @@ ffd4000000000000 - ffd5ffffffffffff (=49 bits) virtual memory map (512TB)
  50  ... unused hole ...
  51  ffdf000000000000 - fffffc0000000000 (=53 bits) kasan shadow memory (8PB)
  52  ... unused hole ...
  53 -fffffe8000000000 - fffffeffffffffff (=39 bits) cpu_entry_area mapping
  54 +fffffe0000000000 - fffffe7fffffffff (=39 bits) cpu_entry_area mapping
  55 +... unused hole ...
  56  ffffff0000000000 - ffffff7fffffffff (=39 bits) %esp fixup stacks
  57  ... unused hole ...
  58  ffffffef00000000 - fffffffeffffffff (=64 GB) EFI region mapping space
  59 diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h
  60 index c92bd73b1e46..0dd48d17a4a1 100644
  61 --- a/arch/x86/include/asm/pgtable_64_types.h
  62 +++ b/arch/x86/include/asm/pgtable_64_types.h
  63 @@ -87,7 +87,7 @@ typedef struct { pteval_t pte; } pte_t;
  64  # define VMALLOC_SIZE_TB       _AC(32, UL)
  65  # define __VMALLOC_BASE                _AC(0xffffc90000000000, UL)
  66  # define __VMEMMAP_BASE                _AC(0xffffea0000000000, UL)
  67 -# define LDT_PGD_ENTRY         _AC(-4, UL)
  68 +# define LDT_PGD_ENTRY         _AC(-3, UL)
  69  # define LDT_BASE_ADDR         (LDT_PGD_ENTRY << PGDIR_SHIFT)
  70  #endif
  71
  72 @@ -109,7 +109,7 @@ typedef struct { pteval_t pte; } pte_t;
  73  #define ESPFIX_PGD_ENTRY       _AC(-2, UL)
  74  #define ESPFIX_BASE_ADDR       (ESPFIX_PGD_ENTRY << P4D_SHIFT)
  75
  76 -#define CPU_ENTRY_AREA_PGD     _AC(-3, UL)
  77 +#define CPU_ENTRY_AREA_PGD     _AC(-4, UL)
  78  #define CPU_ENTRY_AREA_BASE    (CPU_ENTRY_AREA_PGD << P4D_SHIFT)
  79
  80  #define EFI_VA_START           ( -4 * (_AC(1, UL) << 30))
  81 diff --git a/arch/x86/mm/dump_pagetables.c b/arch/x86/mm/dump_pagetables.c
  82 index 12b93d350480..a764bf6f3473 100644
  83 --- a/arch/x86/mm/dump_pagetables.c
  84 +++ b/arch/x86/mm/dump_pagetables.c
  85 @@ -61,10 +61,10 @@ enum address_markers_idx {
  86         KASAN_SHADOW_START_NR,
  87         KASAN_SHADOW_END_NR,
  88  #endif
  89 +       CPU_ENTRY_AREA_NR,
  90  #if defined(CONFIG_MODIFY_LDT_SYSCALL) && !defined(CONFIG_X86_5LEVEL)
  91         LDT_NR,
  92  #endif
  93 -       CPU_ENTRY_AREA_NR,
  94  #ifdef CONFIG_X86_ESPFIX64
  95         ESPFIX_START_NR,
  96  #endif
  97 --
  98 2.14.2
  99