arch/um/Kconfig.i386

   1 menu "Host processor type and features"
   2
   3 source "arch/x86/Kconfig.cpu"
   4
   5 endmenu
   6
   7 config UML_X86
   8         bool
   9         default y
  10
  11 config X86_32
  12        bool
  13        default y
  14
  15 config RWSEM_XCHGADD_ALGORITHM
  16         def_bool y
  17
  18 config 64BIT
  19         bool
  20         default n
  21
  22 config SEMAPHORE_SLEEPERS
  23         bool
  24         default y
  25
  26 choice
  27         prompt "Host memory split"
  28         default HOST_VMSPLIT_3G
  29         help
  30         This is needed when the host kernel on which you run has a non-default
  31         (like 2G/2G) memory split, instead of the customary 3G/1G. If you did
  32         not recompile your own kernel but use the default distro's one, you can
  33         safely accept the "Default split" option.
  34
  35         It can be enabled on recent (>=2.6.16-rc2) vanilla kernels via
  36         CONFIG_VM_SPLIT_*, or on previous kernels with special patches (-ck
  37         patchset by Con Kolivas, or other ones) - option names match closely the
  38         host CONFIG_VM_SPLIT_* ones.
  39
  40         A lower setting (where 1G/3G is lowest and 3G/1G is higher) will
  41         tolerate even more "normal" host kernels, but an higher setting will be
  42         stricter.
  43
  44         So, if you do not know what to do here, say 'Default split'.
  45
  46 config HOST_VMSPLIT_3G
  47         bool "Default split (3G/1G user/kernel host split)"
  48 config HOST_VMSPLIT_3G_OPT
  49         bool "3G/1G user/kernel host split (for full 1G low memory)"
  50 config HOST_VMSPLIT_2G
  51         bool "2G/2G user/kernel host split"
  52 config HOST_VMSPLIT_1G
  53         bool "1G/3G user/kernel host split"
  54 endchoice
  55
  56 config TOP_ADDR
  57         hex
  58         default 0xB0000000 if HOST_VMSPLIT_3G_OPT
  59         default 0x78000000 if HOST_VMSPLIT_2G
  60         default 0x40000000 if HOST_VMSPLIT_1G
  61         default 0xC0000000
  62
  63 config 3_LEVEL_PGTABLES
  64         bool "Three-level pagetables (EXPERIMENTAL)"
  65         default n
  66         depends on EXPERIMENTAL
  67         help
  68         Three-level pagetables will let UML have more than 4G of physical
  69         memory.  All the memory that can't be mapped directly will be treated
  70         as high memory.
  71
  72         However, this it experimental on 32-bit architectures, so if unsure say
  73         N (on x86-64 it's automatically enabled, instead, as it's safe there).
  74
  75 config ARCH_HAS_SC_SIGNALS
  76         bool
  77         default y
  78
  79 config ARCH_REUSE_HOST_VSYSCALL_AREA
  80         bool
  81         default y
  82
  83 config GENERIC_HWEIGHT
  84         bool
  85         default y
  86