Kconfig.um 4.0 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123
  1. config STATIC_LINK
  2. bool "Force a static link"
  3. default n
  4. help
  5. This option gives you the ability to force a static link of UML.
  6. Normally, UML is linked as a shared binary. This is inconvenient for
  7. use in a chroot jail. So, if you intend to run UML inside a chroot,
  8. you probably want to say Y here.
  9. Additionally, this option enables using higher memory spaces (up to
  10. 2.75G) for UML.
  11. source "mm/Kconfig"
  12. config LD_SCRIPT_STATIC
  13. bool
  14. default y
  15. depends on STATIC_LINK
  16. config LD_SCRIPT_DYN
  17. bool
  18. default y
  19. depends on !LD_SCRIPT_STATIC
  20. source "fs/Kconfig.binfmt"
  21. config HOSTFS
  22. tristate "Host filesystem"
  23. help
  24. While the User-Mode Linux port uses its own root file system for
  25. booting and normal file access, this module lets the UML user
  26. access files stored on the host. It does not require any
  27. network connection between the Host and UML. An example use of
  28. this might be:
  29. mount none /tmp/fromhost -t hostfs -o /tmp/umlshare
  30. where /tmp/fromhost is an empty directory inside UML and
  31. /tmp/umlshare is a directory on the host with files the UML user
  32. wishes to access.
  33. For more information, see
  34. <http://user-mode-linux.sourceforge.net/hostfs.html>.
  35. If you'd like to be able to work with files stored on the host,
  36. say Y or M here; otherwise say N.
  37. config MCONSOLE
  38. bool "Management console"
  39. depends on PROC_FS
  40. default y
  41. help
  42. The user mode linux management console is a low-level interface to
  43. the kernel, somewhat like the i386 SysRq interface. Since there is
  44. a full-blown operating system running under every user mode linux
  45. instance, there is much greater flexibility possible than with the
  46. SysRq mechanism.
  47. If you answer 'Y' to this option, to use this feature, you need the
  48. mconsole client (called uml_mconsole) which is present in CVS in
  49. 2.4.5-9um and later (path /tools/mconsole), and is also in the
  50. distribution RPM package in 2.4.6 and later.
  51. It is safe to say 'Y' here.
  52. config MAGIC_SYSRQ
  53. bool "Magic SysRq key"
  54. depends on MCONSOLE
  55. help
  56. If you say Y here, you will have some control over the system even
  57. if the system crashes for example during kernel debugging (e.g., you
  58. will be able to flush the buffer cache to disk, reboot the system
  59. immediately or dump some status information). A key for each of the
  60. possible requests is provided.
  61. This is the feature normally accomplished by pressing a key
  62. while holding SysRq (Alt+PrintScreen).
  63. On UML, this is accomplished by sending a "sysrq" command with
  64. mconsole, followed by the letter for the requested command.
  65. The keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
  66. unless you really know what this hack does.
  67. config KERNEL_STACK_ORDER
  68. int "Kernel stack size order"
  69. default 1 if 64BIT
  70. range 1 10 if 64BIT
  71. default 0 if !64BIT
  72. help
  73. This option determines the size of UML kernel stacks. They will
  74. be 1 << order pages. The default is OK unless you're running Valgrind
  75. on UML, in which case, set this to 3.
  76. config MMAPPER
  77. tristate "iomem emulation driver"
  78. help
  79. This driver allows a host file to be used as emulated IO memory inside
  80. UML.
  81. config NO_DMA
  82. def_bool y
  83. config PGTABLE_LEVELS
  84. int
  85. default 3 if 3_LEVEL_PGTABLES
  86. default 2
  87. config SECCOMP
  88. def_bool y
  89. prompt "Enable seccomp to safely compute untrusted bytecode"
  90. ---help---
  91. This kernel feature is useful for number crunching applications
  92. that may need to compute untrusted bytecode during their
  93. execution. By using pipes or other transports made available to
  94. the process as file descriptors supporting the read/write
  95. syscalls, it's possible to isolate those applications in
  96. their own address space using seccomp. Once seccomp is
  97. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  98. and the task is only allowed to execute a few safe syscalls
  99. defined by each seccomp mode.
  100. If unsure, say Y.