fs/Kconfig.binfmt

   1
   2 menu "Executable file formats"
   3
   4 config BINFMT_ELF
   5         bool "Kernel support for ELF binaries"
   6         depends on MMU
   7         select ELFCORE
   8         default y
   9         ---help---
  10           ELF (Executable and Linkable Format) is a format for libraries and
  11           executables used across different architectures and operating
  12           systems. Saying Y here will enable your kernel to run ELF binaries
  13           and enlarge it by about 13 KB. ELF support under Linux has now all
  14           but replaced the traditional Linux a.out formats (QMAGIC and ZMAGIC)
  15           because it is portable (this does *not* mean that you will be able
  16           to run executables from different architectures or operating systems
  17           however) and makes building run-time libraries very easy. Many new
  18           executables are distributed solely in ELF format. You definitely
  19           want to say Y here.
  20
  21           Information about ELF is contained in the ELF HOWTO available from
  22           <http://www.tldp.org/docs.html#howto>.
  23
  24           If you find that after upgrading from Linux kernel 1.2 and saying Y
  25           here, you still can't run any ELF binaries (they just crash), then
  26           you'll have to install the newest ELF runtime libraries, including
  27           ld.so (check the file <file:Documentation/Changes> for location and
  28           latest version).
  29
  30 config COMPAT_BINFMT_ELF
  31         bool
  32         depends on COMPAT && BINFMT_ELF
  33         select ELFCORE
  34
  35 config ARCH_BINFMT_ELF_STATE
  36         bool
  37
  38 config BINFMT_ELF_FDPIC
  39         bool "Kernel support for FDPIC ELF binaries"
  40         default y if !BINFMT_ELF
  41         depends on (ARM || (SUPERH32 && !MMU) || C6X)
  42         select ELFCORE
  43         help
  44           ELF FDPIC binaries are based on ELF, but allow the individual load
  45           segments of a binary to be located in memory independently of each
  46           other. This makes this format ideal for use in environments where no
  47           MMU is available as it still permits text segments to be shared,
  48           even if data segments are not.
  49
  50           It is also possible to run FDPIC ELF binaries on MMU linux also.
  51
  52 config ELFCORE
  53         bool
  54         help
  55           This option enables kernel/elfcore.o.
  56
  57 config CORE_DUMP_DEFAULT_ELF_HEADERS
  58         bool "Write ELF core dumps with partial segments"
  59         default y
  60         depends on BINFMT_ELF && ELF_CORE
  61         help
  62           ELF core dump files describe each memory mapping of the crashed
  63           process, and can contain or omit the memory contents of each one.
  64           The contents of an unmodified text mapping are omitted by default.
  65
  66           For an unmodified text mapping of an ELF object, including just
  67           the first page of the file in a core dump makes it possible to
  68           identify the build ID bits in the file, without paying the i/o
  69           cost and disk space to dump all the text.  However, versions of
  70           GDB before 6.7 are confused by ELF core dump files in this format.
  71
  72           The core dump behavior can be controlled per process using
  73           the /proc/PID/coredump_filter pseudo-file; this setting is
  74           inherited.  See Documentation/filesystems/proc.txt for details.
  75
  76           This config option changes the default setting of coredump_filter
  77           seen at boot time.  If unsure, say Y.
  78
  79 config BINFMT_SCRIPT
  80         tristate "Kernel support for scripts starting with #!"
  81         default y
  82         help
  83           Say Y here if you want to execute interpreted scripts starting with
  84           #! followed by the path to an interpreter.
  85
  86           You can build this support as a module; however, until that module
  87           gets loaded, you cannot run scripts.  Thus, if you want to load this
  88           module from an initramfs, the portion of the initramfs before loading
  89           this module must consist of compiled binaries only.
  90
  91           Most systems will not boot if you say M or N here.  If unsure, say Y.
  92
  93 config BINFMT_FLAT
  94         bool "Kernel support for flat binaries"
  95         depends on !MMU || ARM || M68K
  96         help
  97           Support uClinux FLAT format binaries.
  98
  99 config BINFMT_ZFLAT
 100         bool "Enable ZFLAT support"
 101         depends on BINFMT_FLAT
 102         select ZLIB_INFLATE
 103         help
 104           Support FLAT format compressed binaries
 105
 106 config BINFMT_SHARED_FLAT
 107         bool "Enable shared FLAT support"
 108         depends on BINFMT_FLAT
 109         help
 110           Support FLAT shared libraries
 111
 112 config HAVE_AOUT
 113        def_bool n
 114
 115 config BINFMT_AOUT
 116         tristate "Kernel support for a.out and ECOFF binaries"
 117         depends on HAVE_AOUT
 118         ---help---
 119           A.out (Assembler.OUTput) is a set of formats for libraries and
 120           executables used in the earliest versions of UNIX.  Linux used
 121           the a.out formats QMAGIC and ZMAGIC until they were replaced
 122           with the ELF format.
 123
 124           The conversion to ELF started in 1995.  This option is primarily
 125           provided for historical interest and for the benefit of those
 126           who need to run binaries from that era.
 127
 128           Most people should answer N here.  If you think you may have
 129           occasional use for this format, enable module support above
 130           and answer M here to compile this support as a module called
 131           binfmt_aout.
 132
 133           If any crucial components of your system (such as /sbin/init
 134           or /lib/ld.so) are still in a.out format, you will have to
 135           say Y here.
 136
 137 config OSF4_COMPAT
 138         bool "OSF/1 v4 readv/writev compatibility"
 139         depends on ALPHA && BINFMT_AOUT
 140         help
 141           Say Y if you are using OSF/1 binaries (like Netscape and Acrobat)
 142           with v4 shared libraries freely available from Compaq. If you're
 143           going to use shared libraries from Tru64 version 5.0 or later, say N.
 144
 145 config BINFMT_EM86
 146         tristate "Kernel support for Linux/Intel ELF binaries"
 147         depends on ALPHA
 148         ---help---
 149           Say Y here if you want to be able to execute Linux/Intel ELF
 150           binaries just like native Alpha binaries on your Alpha machine. For
 151           this to work, you need to have the emulator /usr/bin/em86 in place.
 152
 153           You can get the same functionality by saying N here and saying Y to
 154           "Kernel support for MISC binaries".
 155
 156           You may answer M to compile the emulation support as a module and
 157           later load the module when you want to use a Linux/Intel binary. The
 158           module will be called binfmt_em86. If unsure, say Y.
 159
 160 config BINFMT_MISC
 161         tristate "Kernel support for MISC binaries"
 162         ---help---
 163           If you say Y here, it will be possible to plug wrapper-driven binary
 164           formats into the kernel. You will like this especially when you use
 165           programs that need an interpreter to run like Java, Python, .NET or
 166           Emacs-Lisp. It's also useful if you often run DOS executables under
 167           the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from
 168           <http://www.tldp.org/docs.html#howto>). Once you have
 169           registered such a binary class with the kernel, you can start one of
 170           those programs simply by typing in its name at a shell prompt; Linux
 171           will automatically feed it to the correct interpreter.
 172
 173           You can do other nice things, too. Read the file
 174           <file:Documentation/admin-guide/binfmt-misc.rst> to learn how to use this
 175           feature, <file:Documentation/admin-guide/java.rst> for information about how
 176           to include Java support. and <file:Documentation/admin-guide/mono.rst> for
 177           information about how to include Mono-based .NET support.
 178
 179           To use binfmt_misc, you will need to mount it:
 180                 mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc
 181
 182           You may say M here for module support and later load the module when
 183           you have use for it; the module is called binfmt_misc. If you
 184           don't know what to answer at this point, say Y.
 185
 186 config COREDUMP
 187         bool "Enable core dump support" if EXPERT
 188         default y
 189         help
 190           This option enables support for performing core dumps. You almost
 191           certainly want to say Y here. Not necessary on systems that never
 192           need debugging or only ever run flawless code.
 193
 194 endmenu