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 bool 33 depends on COMPAT && BINFMT_ELF 34 select ELFCORE 35 36config ARCH_BINFMT_ELF_STATE 37 bool 38 39config BINFMT_ELF_FDPIC 40 bool "Kernel support for FDPIC ELF binaries" 41 default y if !BINFMT_ELF 42 depends on (ARM || (SUPERH32 && !MMU) || C6X) 43 select ELFCORE 44 help 45 ELF FDPIC binaries are based on ELF, but allow the individual load 46 segments of a binary to be located in memory independently of each 47 other. This makes this format ideal for use in environments where no 48 MMU is available as it still permits text segments to be shared, 49 even if data segments are not. 50 51 It is also possible to run FDPIC ELF binaries on MMU linux also. 52 53config ELFCORE 54 bool 55 help 56 This option enables kernel/elfcore.o. 57 58config CORE_DUMP_DEFAULT_ELF_HEADERS 59 bool "Write ELF core dumps with partial segments" 60 default y 61 depends on BINFMT_ELF && ELF_CORE 62 help 63 ELF core dump files describe each memory mapping of the crashed 64 process, and can contain or omit the memory contents of each one. 65 The contents of an unmodified text mapping are omitted by default. 66 67 For an unmodified text mapping of an ELF object, including just 68 the first page of the file in a core dump makes it possible to 69 identify the build ID bits in the file, without paying the i/o 70 cost and disk space to dump all the text. However, versions of 71 GDB before 6.7 are confused by ELF core dump files in this format. 72 73 The core dump behavior can be controlled per process using 74 the /proc/PID/coredump_filter pseudo-file; this setting is 75 inherited. See Documentation/filesystems/proc.txt for details. 76 77 This config option changes the default setting of coredump_filter 78 seen at boot time. If unsure, say Y. 79 80config BINFMT_SCRIPT 81 tristate "Kernel support for scripts starting with #!" 82 default y 83 help 84 Say Y here if you want to execute interpreted scripts starting with 85 #! followed by the path to an interpreter. 86 87 You can build this support as a module; however, until that module 88 gets loaded, you cannot run scripts. Thus, if you want to load this 89 module from an initramfs, the portion of the initramfs before loading 90 this module must consist of compiled binaries only. 91 92 Most systems will not boot if you say M or N here. If unsure, say Y. 93 94config ARCH_HAS_BINFMT_FLAT 95 bool 96 97config BINFMT_FLAT 98 bool "Kernel support for flat binaries" 99 depends on ARCH_HAS_BINFMT_FLAT 100 help 101 Support uClinux FLAT format binaries. 102 103config BINFMT_FLAT_ARGVP_ENVP_ON_STACK 104 bool 105 106config BINFMT_FLAT_OLD_ALWAYS_RAM 107 bool 108 109config BINFMT_FLAT_OLD 110 bool "Enable support for very old legacy flat binaries" 111 depends on BINFMT_FLAT 112 help 113 Support decade old uClinux FLAT format binaries. Unless you know 114 you have some of those say N here. 115 116config BINFMT_ZFLAT 117 bool "Enable ZFLAT support" 118 depends on BINFMT_FLAT 119 select ZLIB_INFLATE 120 help 121 Support FLAT format compressed binaries 122 123config BINFMT_SHARED_FLAT 124 bool "Enable shared FLAT support" 125 depends on BINFMT_FLAT 126 help 127 Support FLAT shared libraries 128 129config HAVE_AOUT 130 def_bool n 131 132config BINFMT_AOUT 133 tristate "Kernel support for a.out and ECOFF binaries" 134 depends on HAVE_AOUT 135 ---help--- 136 A.out (Assembler.OUTput) is a set of formats for libraries and 137 executables used in the earliest versions of UNIX. Linux used 138 the a.out formats QMAGIC and ZMAGIC until they were replaced 139 with the ELF format. 140 141 The conversion to ELF started in 1995. This option is primarily 142 provided for historical interest and for the benefit of those 143 who need to run binaries from that era. 144 145 Most people should answer N here. If you think you may have 146 occasional use for this format, enable module support above 147 and answer M here to compile this support as a module called 148 binfmt_aout. 149 150 If any crucial components of your system (such as /sbin/init 151 or /lib/ld.so) are still in a.out format, you will have to 152 say Y here. 153 154config OSF4_COMPAT 155 bool "OSF/1 v4 readv/writev compatibility" 156 depends on ALPHA && BINFMT_AOUT 157 help 158 Say Y if you are using OSF/1 binaries (like Netscape and Acrobat) 159 with v4 shared libraries freely available from Compaq. If you're 160 going to use shared libraries from Tru64 version 5.0 or later, say N. 161 162config BINFMT_EM86 163 tristate "Kernel support for Linux/Intel ELF binaries" 164 depends on ALPHA 165 ---help--- 166 Say Y here if you want to be able to execute Linux/Intel ELF 167 binaries just like native Alpha binaries on your Alpha machine. For 168 this to work, you need to have the emulator /usr/bin/em86 in place. 169 170 You can get the same functionality by saying N here and saying Y to 171 "Kernel support for MISC binaries". 172 173 You may answer M to compile the emulation support as a module and 174 later load the module when you want to use a Linux/Intel binary. The 175 module will be called binfmt_em86. If unsure, say Y. 176 177config BINFMT_MISC 178 tristate "Kernel support for MISC binaries" 179 ---help--- 180 If you say Y here, it will be possible to plug wrapper-driven binary 181 formats into the kernel. You will like this especially when you use 182 programs that need an interpreter to run like Java, Python, .NET or 183 Emacs-Lisp. It's also useful if you often run DOS executables under 184 the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from 185 <http://www.tldp.org/docs.html#howto>). Once you have 186 registered such a binary class with the kernel, you can start one of 187 those programs simply by typing in its name at a shell prompt; Linux 188 will automatically feed it to the correct interpreter. 189 190 You can do other nice things, too. Read the file 191 <file:Documentation/admin-guide/binfmt-misc.rst> to learn how to use this 192 feature, <file:Documentation/admin-guide/java.rst> for information about how 193 to include Java support. and <file:Documentation/admin-guide/mono.rst> for 194 information about how to include Mono-based .NET support. 195 196 To use binfmt_misc, you will need to mount it: 197 mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc 198 199 You may say M here for module support and later load the module when 200 you have use for it; the module is called binfmt_misc. If you 201 don't know what to answer at this point, say Y. 202 203config COREDUMP 204 bool "Enable core dump support" if EXPERT 205 default y 206 help 207 This option enables support for performing core dumps. You almost 208 certainly want to say Y here. Not necessary on systems that never 209 need debugging or only ever run flawless code. 210 211endmenu 212
