1# SPDX-License-Identifier: GPL-2.0-only 2 3menu "Executable file formats" 4 5config BINFMT_ELF 6 bool "Kernel support for ELF binaries" 7 depends on MMU 8 select ELFCORE 9 default y 10 help 11 ELF (Executable and Linkable Format) is a format for libraries and 12 executables used across different architectures and operating 13 systems. Saying Y here will enable your kernel to run ELF binaries 14 and enlarge it by about 13 KB. ELF support under Linux has now all 15 but replaced the traditional Linux a.out formats (QMAGIC and ZMAGIC) 16 because it is portable (this does *not* mean that you will be able 17 to run executables from different architectures or operating systems 18 however) and makes building run-time libraries very easy. Many new 19 executables are distributed solely in ELF format. You definitely 20 want to say Y here. 21 22 Information about ELF is contained in the ELF HOWTO available from 23 <http://www.tldp.org/docs.html#howto>. 24 25 If you find that after upgrading from Linux kernel 1.2 and saying Y 26 here, you still can't run any ELF binaries (they just crash), then 27 you'll have to install the newest ELF runtime libraries, including 28 ld.so (check the file <file:Documentation/Changes> for location and 29 latest version). 30 31config COMPAT_BINFMT_ELF 32 def_bool y 33 depends on COMPAT && BINFMT_ELF 34 select ELFCORE 35 36config ARCH_BINFMT_ELF_STATE 37 bool 38 39config ARCH_HAVE_ELF_PROT 40 bool 41 42config ARCH_USE_GNU_PROPERTY 43 bool 44 45config BINFMT_ELF_FDPIC 46 bool "Kernel support for FDPIC ELF binaries" 47 default y if !BINFMT_ELF 48 depends on (ARM || (SUPERH && !MMU)) 49 select ELFCORE 50 help 51 ELF FDPIC binaries are based on ELF, but allow the individual load 52 segments of a binary to be located in memory independently of each 53 other. This makes this format ideal for use in environments where no 54 MMU is available as it still permits text segments to be shared, 55 even if data segments are not. 56 57 It is also possible to run FDPIC ELF binaries on MMU linux also. 58 59config ELFCORE 60 bool 61 help 62 This option enables kernel/elfcore.o. 63 64config CORE_DUMP_DEFAULT_ELF_HEADERS 65 bool "Write ELF core dumps with partial segments" 66 default y 67 depends on BINFMT_ELF && ELF_CORE 68 help 69 ELF core dump files describe each memory mapping of the crashed 70 process, and can contain or omit the memory contents of each one. 71 The contents of an unmodified text mapping are omitted by default. 72 73 For an unmodified text mapping of an ELF object, including just 74 the first page of the file in a core dump makes it possible to 75 identify the build ID bits in the file, without paying the i/o 76 cost and disk space to dump all the text. However, versions of 77 GDB before 6.7 are confused by ELF core dump files in this format. 78 79 The core dump behavior can be controlled per process using 80 the /proc/PID/coredump_filter pseudo-file; this setting is 81 inherited. See Documentation/filesystems/proc.rst for details. 82 83 This config option changes the default setting of coredump_filter 84 seen at boot time. If unsure, say Y. 85 86config BINFMT_SCRIPT 87 tristate "Kernel support for scripts starting with #!" 88 default y 89 help 90 Say Y here if you want to execute interpreted scripts starting with 91 #! followed by the path to an interpreter. 92 93 You can build this support as a module; however, until that module 94 gets loaded, you cannot run scripts. Thus, if you want to load this 95 module from an initramfs, the portion of the initramfs before loading 96 this module must consist of compiled binaries only. 97 98 Most systems will not boot if you say M or N here. If unsure, say Y. 99 100config ARCH_HAS_BINFMT_FLAT 101 bool 102 103config BINFMT_FLAT 104 bool "Kernel support for flat binaries" 105 depends on ARCH_HAS_BINFMT_FLAT 106 help 107 Support uClinux FLAT format binaries. 108 109config BINFMT_FLAT_ARGVP_ENVP_ON_STACK 110 bool 111 112config BINFMT_FLAT_OLD_ALWAYS_RAM 113 bool 114 115config BINFMT_FLAT_OLD 116 bool "Enable support for very old legacy flat binaries" 117 depends on BINFMT_FLAT 118 help 119 Support decade old uClinux FLAT format binaries. Unless you know 120 you have some of those say N here. 121 122config BINFMT_ZFLAT 123 bool "Enable ZFLAT support" 124 depends on BINFMT_FLAT 125 select ZLIB_INFLATE 126 help 127 Support FLAT format compressed binaries 128 129config BINFMT_SHARED_FLAT 130 bool "Enable shared FLAT support" 131 depends on BINFMT_FLAT 132 help 133 Support FLAT shared libraries 134 135config HAVE_AOUT 136 def_bool n 137 138config BINFMT_AOUT 139 tristate "Kernel support for a.out and ECOFF binaries" 140 depends on HAVE_AOUT 141 help 142 A.out (Assembler.OUTput) is a set of formats for libraries and 143 executables used in the earliest versions of UNIX. Linux used 144 the a.out formats QMAGIC and ZMAGIC until they were replaced 145 with the ELF format. 146 147 The conversion to ELF started in 1995. This option is primarily 148 provided for historical interest and for the benefit of those 149 who need to run binaries from that era. 150 151 Most people should answer N here. If you think you may have 152 occasional use for this format, enable module support above 153 and answer M here to compile this support as a module called 154 binfmt_aout. 155 156 If any crucial components of your system (such as /sbin/init 157 or /lib/ld.so) are still in a.out format, you will have to 158 say Y here. 159 160config OSF4_COMPAT 161 bool "OSF/1 v4 readv/writev compatibility" 162 depends on ALPHA && BINFMT_AOUT 163 help 164 Say Y if you are using OSF/1 binaries (like Netscape and Acrobat) 165 with v4 shared libraries freely available from Compaq. If you're 166 going to use shared libraries from Tru64 version 5.0 or later, say N. 167 168config BINFMT_EM86 169 tristate "Kernel support for Linux/Intel ELF binaries" 170 depends on ALPHA 171 help 172 Say Y here if you want to be able to execute Linux/Intel ELF 173 binaries just like native Alpha binaries on your Alpha machine. For 174 this to work, you need to have the emulator /usr/bin/em86 in place. 175 176 You can get the same functionality by saying N here and saying Y to 177 "Kernel support for MISC binaries". 178 179 You may answer M to compile the emulation support as a module and 180 later load the module when you want to use a Linux/Intel binary. The 181 module will be called binfmt_em86. If unsure, say Y. 182 183config BINFMT_MISC 184 tristate "Kernel support for MISC binaries" 185 help 186 If you say Y here, it will be possible to plug wrapper-driven binary 187 formats into the kernel. You will like this especially when you use 188 programs that need an interpreter to run like Java, Python, .NET or 189 Emacs-Lisp. It's also useful if you often run DOS executables under 190 the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from 191 <http://www.tldp.org/docs.html#howto>). Once you have 192 registered such a binary class with the kernel, you can start one of 193 those programs simply by typing in its name at a shell prompt; Linux 194 will automatically feed it to the correct interpreter. 195 196 You can do other nice things, too. Read the file 197 <file:Documentation/admin-guide/binfmt-misc.rst> to learn how to use this 198 feature, <file:Documentation/admin-guide/java.rst> for information about how 199 to include Java support. and <file:Documentation/admin-guide/mono.rst> for 200 information about how to include Mono-based .NET support. 201 202 To use binfmt_misc, you will need to mount it: 203 mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc 204 205 You may say M here for module support and later load the module when 206 you have use for it; the module is called binfmt_misc. If you 207 don't know what to answer at this point, say Y. 208 209config COREDUMP 210 bool "Enable core dump support" if EXPERT 211 default y 212 help 213 This option enables support for performing core dumps. You almost 214 certainly want to say Y here. Not necessary on systems that never 215 need debugging or only ever run flawless code. 216 217endmenu 218