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 BINFMT_ELF_KUNIT_TEST 32 bool "Build KUnit tests for ELF binary support" if !KUNIT_ALL_TESTS 33 depends on KUNIT=y && BINFMT_ELF=y 34 default KUNIT_ALL_TESTS 35 help 36 This builds the ELF loader KUnit tests, which try to gather 37 prior bug fixes into a regression test collection. This is really 38 only needed for debugging. Note that with CONFIG_COMPAT=y, the 39 compat_binfmt_elf KUnit test is also created. 40 41config COMPAT_BINFMT_ELF 42 def_bool y 43 depends on COMPAT && BINFMT_ELF 44 select ELFCORE 45 46config ARCH_BINFMT_ELF_STATE 47 bool 48 49config ARCH_BINFMT_ELF_EXTRA_PHDRS 50 bool 51 52config ARCH_HAVE_ELF_PROT 53 bool 54 55config ARCH_USE_GNU_PROPERTY 56 bool 57 58config BINFMT_ELF_FDPIC 59 bool "Kernel support for FDPIC ELF binaries" 60 default y if !BINFMT_ELF 61 depends on (ARM || (SUPERH && !MMU)) 62 select ELFCORE 63 help 64 ELF FDPIC binaries are based on ELF, but allow the individual load 65 segments of a binary to be located in memory independently of each 66 other. This makes this format ideal for use in environments where no 67 MMU is available as it still permits text segments to be shared, 68 even if data segments are not. 69 70 It is also possible to run FDPIC ELF binaries on MMU linux also. 71 72config ELFCORE 73 bool 74 help 75 This option enables kernel/elfcore.o. 76 77config CORE_DUMP_DEFAULT_ELF_HEADERS 78 bool "Write ELF core dumps with partial segments" 79 default y 80 depends on BINFMT_ELF && ELF_CORE 81 help 82 ELF core dump files describe each memory mapping of the crashed 83 process, and can contain or omit the memory contents of each one. 84 The contents of an unmodified text mapping are omitted by default. 85 86 For an unmodified text mapping of an ELF object, including just 87 the first page of the file in a core dump makes it possible to 88 identify the build ID bits in the file, without paying the i/o 89 cost and disk space to dump all the text. However, versions of 90 GDB before 6.7 are confused by ELF core dump files in this format. 91 92 The core dump behavior can be controlled per process using 93 the /proc/PID/coredump_filter pseudo-file; this setting is 94 inherited. See Documentation/filesystems/proc.rst for details. 95 96 This config option changes the default setting of coredump_filter 97 seen at boot time. If unsure, say Y. 98 99config BINFMT_SCRIPT 100 tristate "Kernel support for scripts starting with #!" 101 default y 102 help 103 Say Y here if you want to execute interpreted scripts starting with 104 #! followed by the path to an interpreter. 105 106 You can build this support as a module; however, until that module 107 gets loaded, you cannot run scripts. Thus, if you want to load this 108 module from an initramfs, the portion of the initramfs before loading 109 this module must consist of compiled binaries only. 110 111 Most systems will not boot if you say M or N here. If unsure, say Y. 112 113config ARCH_HAS_BINFMT_FLAT 114 bool 115 116config BINFMT_FLAT 117 bool "Kernel support for flat binaries" 118 depends on ARCH_HAS_BINFMT_FLAT 119 help 120 Support uClinux FLAT format binaries. 121 122config BINFMT_FLAT_ARGVP_ENVP_ON_STACK 123 bool 124 125config BINFMT_FLAT_OLD_ALWAYS_RAM 126 bool 127 128config BINFMT_FLAT_NO_DATA_START_OFFSET 129 bool 130 131config BINFMT_FLAT_OLD 132 bool "Enable support for very old legacy flat binaries" 133 depends on BINFMT_FLAT 134 help 135 Support decade old uClinux FLAT format binaries. Unless you know 136 you have some of those say N here. 137 138config BINFMT_ZFLAT 139 bool "Enable ZFLAT support" 140 depends on BINFMT_FLAT 141 select ZLIB_INFLATE 142 help 143 Support FLAT format compressed binaries 144 145config BINFMT_SHARED_FLAT 146 bool "Enable shared FLAT support" 147 depends on BINFMT_FLAT 148 help 149 Support FLAT shared libraries 150 151config HAVE_AOUT 152 def_bool n 153 154config BINFMT_AOUT 155 tristate "Kernel support for a.out and ECOFF binaries" 156 depends on HAVE_AOUT 157 help 158 A.out (Assembler.OUTput) is a set of formats for libraries and 159 executables used in the earliest versions of UNIX. Linux used 160 the a.out formats QMAGIC and ZMAGIC until they were replaced 161 with the ELF format. 162 163 The conversion to ELF started in 1995. This option is primarily 164 provided for historical interest and for the benefit of those 165 who need to run binaries from that era. 166 167 Most people should answer N here. If you think you may have 168 occasional use for this format, enable module support above 169 and answer M here to compile this support as a module called 170 binfmt_aout. 171 172 If any crucial components of your system (such as /sbin/init 173 or /lib/ld.so) are still in a.out format, you will have to 174 say Y here. 175 176config OSF4_COMPAT 177 bool "OSF/1 v4 readv/writev compatibility" 178 depends on ALPHA && BINFMT_AOUT 179 help 180 Say Y if you are using OSF/1 binaries (like Netscape and Acrobat) 181 with v4 shared libraries freely available from Compaq. If you're 182 going to use shared libraries from Tru64 version 5.0 or later, say N. 183 184config BINFMT_MISC 185 tristate "Kernel support for MISC binaries" 186 help 187 If you say Y here, it will be possible to plug wrapper-driven binary 188 formats into the kernel. You will like this especially when you use 189 programs that need an interpreter to run like Java, Python, .NET or 190 Emacs-Lisp. It's also useful if you often run DOS executables under 191 the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from 192 <http://www.tldp.org/docs.html#howto>). Once you have 193 registered such a binary class with the kernel, you can start one of 194 those programs simply by typing in its name at a shell prompt; Linux 195 will automatically feed it to the correct interpreter. 196 197 You can do other nice things, too. Read the file 198 <file:Documentation/admin-guide/binfmt-misc.rst> to learn how to use this 199 feature, <file:Documentation/admin-guide/java.rst> for information about how 200 to include Java support. and <file:Documentation/admin-guide/mono.rst> for 201 information about how to include Mono-based .NET support. 202 203 To use binfmt_misc, you will need to mount it: 204 mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc 205 206 You may say M here for module support and later load the module when 207 you have use for it; the module is called binfmt_misc. If you 208 don't know what to answer at this point, say Y. 209 210config COREDUMP 211 bool "Enable core dump support" if EXPERT 212 default y 213 help 214 This option enables support for performing core dumps. You almost 215 certainly want to say Y here. Not necessary on systems that never 216 need debugging or only ever run flawless code. 217 218endmenu 219