1 # SPDX-License-Identifier: GPL-2.0-only 1 # SPDX-License-Identifier: GPL-2.0-only
2 2
3 menu "Executable file formats" 3 menu "Executable file formats"
4 4
5 config BINFMT_ELF 5 config BINFMT_ELF
6 bool "Kernel support for ELF binaries" 6 bool "Kernel support for ELF binaries"
7 depends on MMU 7 depends on MMU
8 select ELFCORE 8 select ELFCORE
9 default y 9 default y
10 help 10 help
11 ELF (Executable and Linkable Format) 11 ELF (Executable and Linkable Format) is a format for libraries and
12 executables used across different ar 12 executables used across different architectures and operating
13 systems. Saying Y here will enable y 13 systems. Saying Y here will enable your kernel to run ELF binaries
14 and enlarge it by about 13 KB. ELF s 14 and enlarge it by about 13 KB. ELF support under Linux has now all
15 but replaced the traditional Linux a 15 but replaced the traditional Linux a.out formats (QMAGIC and ZMAGIC)
16 because it is portable (this does *n 16 because it is portable (this does *not* mean that you will be able
17 to run executables from different ar 17 to run executables from different architectures or operating systems
18 however) and makes building run-time 18 however) and makes building run-time libraries very easy. Many new
19 executables are distributed solely i 19 executables are distributed solely in ELF format. You definitely
20 want to say Y here. 20 want to say Y here.
21 21
22 Information about ELF is contained i 22 Information about ELF is contained in the ELF HOWTO available from
23 <http://www.tldp.org/docs.html#howto 23 <http://www.tldp.org/docs.html#howto>.
24 24
25 If you find that after upgrading fro 25 If you find that after upgrading from Linux kernel 1.2 and saying Y
26 here, you still can't run any ELF bi 26 here, you still can't run any ELF binaries (they just crash), then
27 you'll have to install the newest EL 27 you'll have to install the newest ELF runtime libraries, including
28 ld.so (check the file <file:Document 28 ld.so (check the file <file:Documentation/Changes> for location and
29 latest version). 29 latest version).
30 30
31 config BINFMT_ELF_KUNIT_TEST 31 config BINFMT_ELF_KUNIT_TEST
32 bool "Build KUnit tests for ELF binary 32 bool "Build KUnit tests for ELF binary support" if !KUNIT_ALL_TESTS
33 depends on KUNIT=y && BINFMT_ELF=y 33 depends on KUNIT=y && BINFMT_ELF=y
34 default KUNIT_ALL_TESTS 34 default KUNIT_ALL_TESTS
35 help 35 help
36 This builds the ELF loader KUnit tes 36 This builds the ELF loader KUnit tests, which try to gather
37 prior bug fixes into a regression te 37 prior bug fixes into a regression test collection. This is really
38 only needed for debugging. Note that 38 only needed for debugging. Note that with CONFIG_COMPAT=y, the
39 compat_binfmt_elf KUnit test is also 39 compat_binfmt_elf KUnit test is also created.
40 40
41 config COMPAT_BINFMT_ELF 41 config COMPAT_BINFMT_ELF
42 def_bool y 42 def_bool y
43 depends on COMPAT && BINFMT_ELF 43 depends on COMPAT && BINFMT_ELF
44 select ELFCORE 44 select ELFCORE
45 45
46 config ARCH_BINFMT_ELF_STATE 46 config ARCH_BINFMT_ELF_STATE
47 bool 47 bool
48 48
49 config ARCH_BINFMT_ELF_EXTRA_PHDRS 49 config ARCH_BINFMT_ELF_EXTRA_PHDRS
50 bool 50 bool
51 51
52 config ARCH_HAVE_ELF_PROT 52 config ARCH_HAVE_ELF_PROT
53 bool 53 bool
54 54
55 config ARCH_USE_GNU_PROPERTY 55 config ARCH_USE_GNU_PROPERTY
56 bool 56 bool
57 57
58 config BINFMT_ELF_FDPIC 58 config BINFMT_ELF_FDPIC
59 bool "Kernel support for FDPIC ELF bin 59 bool "Kernel support for FDPIC ELF binaries"
60 default y if !BINFMT_ELF 60 default y if !BINFMT_ELF
61 depends on ARM || ((M68K || RISCV || S !! 61 depends on ARM || ((M68K || SUPERH) && !MMU)
62 select ELFCORE 62 select ELFCORE
63 help 63 help
64 ELF FDPIC binaries are based on ELF, 64 ELF FDPIC binaries are based on ELF, but allow the individual load
65 segments of a binary to be located i 65 segments of a binary to be located in memory independently of each
66 other. This makes this format ideal 66 other. This makes this format ideal for use in environments where no
67 MMU is available as it still permits 67 MMU is available as it still permits text segments to be shared,
68 even if data segments are not. 68 even if data segments are not.
69 69
70 It is also possible to run FDPIC ELF 70 It is also possible to run FDPIC ELF binaries on MMU linux also.
71 71
72 config ELFCORE 72 config ELFCORE
73 bool 73 bool
74 help 74 help
75 This option enables kernel/elfcore.o 75 This option enables kernel/elfcore.o.
76 76
77 config CORE_DUMP_DEFAULT_ELF_HEADERS 77 config CORE_DUMP_DEFAULT_ELF_HEADERS
78 bool "Write ELF core dumps with partia 78 bool "Write ELF core dumps with partial segments"
79 default y 79 default y
80 depends on BINFMT_ELF && ELF_CORE 80 depends on BINFMT_ELF && ELF_CORE
81 help 81 help
82 ELF core dump files describe each me 82 ELF core dump files describe each memory mapping of the crashed
83 process, and can contain or omit the 83 process, and can contain or omit the memory contents of each one.
84 The contents of an unmodified text m 84 The contents of an unmodified text mapping are omitted by default.
85 85
86 For an unmodified text mapping of an 86 For an unmodified text mapping of an ELF object, including just
87 the first page of the file in a core 87 the first page of the file in a core dump makes it possible to
88 identify the build ID bits in the fi 88 identify the build ID bits in the file, without paying the i/o
89 cost and disk space to dump all the 89 cost and disk space to dump all the text. However, versions of
90 GDB before 6.7 are confused by ELF c 90 GDB before 6.7 are confused by ELF core dump files in this format.
91 91
92 The core dump behavior can be contro 92 The core dump behavior can be controlled per process using
93 the /proc/PID/coredump_filter pseudo 93 the /proc/PID/coredump_filter pseudo-file; this setting is
94 inherited. See Documentation/filesy 94 inherited. See Documentation/filesystems/proc.rst for details.
95 95
96 This config option changes the defau 96 This config option changes the default setting of coredump_filter
97 seen at boot time. If unsure, say Y 97 seen at boot time. If unsure, say Y.
98 98
99 config BINFMT_SCRIPT 99 config BINFMT_SCRIPT
100 tristate "Kernel support for scripts s 100 tristate "Kernel support for scripts starting with #!"
101 default y 101 default y
102 help 102 help
103 Say Y here if you want to execute in 103 Say Y here if you want to execute interpreted scripts starting with
104 #! followed by the path to an interp 104 #! followed by the path to an interpreter.
105 105
106 You can build this support as a modu 106 You can build this support as a module; however, until that module
107 gets loaded, you cannot run scripts. 107 gets loaded, you cannot run scripts. Thus, if you want to load this
108 module from an initramfs, the portio 108 module from an initramfs, the portion of the initramfs before loading
109 this module must consist of compiled 109 this module must consist of compiled binaries only.
110 110
111 Most systems will not boot if you sa 111 Most systems will not boot if you say M or N here. If unsure, say Y.
112 112
113 config ARCH_HAS_BINFMT_FLAT 113 config ARCH_HAS_BINFMT_FLAT
114 bool 114 bool
115 115
116 config BINFMT_FLAT 116 config BINFMT_FLAT
117 bool "Kernel support for flat binaries 117 bool "Kernel support for flat binaries"
118 depends on ARCH_HAS_BINFMT_FLAT 118 depends on ARCH_HAS_BINFMT_FLAT
119 help 119 help
120 Support uClinux FLAT format binaries 120 Support uClinux FLAT format binaries.
121 121
122 config BINFMT_FLAT_ARGVP_ENVP_ON_STACK 122 config BINFMT_FLAT_ARGVP_ENVP_ON_STACK
123 bool 123 bool
124 124
125 config BINFMT_FLAT_OLD_ALWAYS_RAM 125 config BINFMT_FLAT_OLD_ALWAYS_RAM
126 bool 126 bool
127 127
128 config BINFMT_FLAT_NO_DATA_START_OFFSET 128 config BINFMT_FLAT_NO_DATA_START_OFFSET
129 bool 129 bool
130 130
131 config BINFMT_FLAT_OLD 131 config BINFMT_FLAT_OLD
132 bool "Enable support for very old lega 132 bool "Enable support for very old legacy flat binaries"
133 depends on BINFMT_FLAT 133 depends on BINFMT_FLAT
134 help 134 help
135 Support decade old uClinux FLAT form 135 Support decade old uClinux FLAT format binaries. Unless you know
136 you have some of those say N here. 136 you have some of those say N here.
137 137
138 config BINFMT_ZFLAT 138 config BINFMT_ZFLAT
139 bool "Enable ZFLAT support" 139 bool "Enable ZFLAT support"
140 depends on BINFMT_FLAT 140 depends on BINFMT_FLAT
141 select ZLIB_INFLATE 141 select ZLIB_INFLATE
142 help 142 help
143 Support FLAT format compressed binar 143 Support FLAT format compressed binaries
144 144
>> 145 config HAVE_AOUT
>> 146 def_bool n
>> 147
>> 148 config BINFMT_AOUT
>> 149 tristate "Kernel support for a.out and ECOFF binaries"
>> 150 depends on HAVE_AOUT
>> 151 help
>> 152 A.out (Assembler.OUTput) is a set of formats for libraries and
>> 153 executables used in the earliest versions of UNIX. Linux used
>> 154 the a.out formats QMAGIC and ZMAGIC until they were replaced
>> 155 with the ELF format.
>> 156
>> 157 The conversion to ELF started in 1995. This option is primarily
>> 158 provided for historical interest and for the benefit of those
>> 159 who need to run binaries from that era.
>> 160
>> 161 Most people should answer N here. If you think you may have
>> 162 occasional use for this format, enable module support above
>> 163 and answer M here to compile this support as a module called
>> 164 binfmt_aout.
>> 165
>> 166 If any crucial components of your system (such as /sbin/init
>> 167 or /lib/ld.so) are still in a.out format, you will have to
>> 168 say Y here.
>> 169
>> 170 config OSF4_COMPAT
>> 171 bool "OSF/1 v4 readv/writev compatibility"
>> 172 depends on ALPHA && BINFMT_AOUT
>> 173 help
>> 174 Say Y if you are using OSF/1 binaries (like Netscape and Acrobat)
>> 175 with v4 shared libraries freely available from Compaq. If you're
>> 176 going to use shared libraries from Tru64 version 5.0 or later, say N.
>> 177
145 config BINFMT_MISC 178 config BINFMT_MISC
146 tristate "Kernel support for MISC bina 179 tristate "Kernel support for MISC binaries"
147 help 180 help
148 If you say Y here, it will be possib 181 If you say Y here, it will be possible to plug wrapper-driven binary
149 formats into the kernel. You will li 182 formats into the kernel. You will like this especially when you use
150 programs that need an interpreter to 183 programs that need an interpreter to run like Java, Python, .NET or
151 Emacs-Lisp. It's also useful if you 184 Emacs-Lisp. It's also useful if you often run DOS executables under
152 the Linux DOS emulator DOSEMU (read 185 the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from
153 <http://www.tldp.org/docs.html#howto 186 <http://www.tldp.org/docs.html#howto>). Once you have
154 registered such a binary class with 187 registered such a binary class with the kernel, you can start one of
155 those programs simply by typing in i 188 those programs simply by typing in its name at a shell prompt; Linux
156 will automatically feed it to the co 189 will automatically feed it to the correct interpreter.
157 190
158 You can do other nice things, too. R 191 You can do other nice things, too. Read the file
159 <file:Documentation/admin-guide/binf 192 <file:Documentation/admin-guide/binfmt-misc.rst> to learn how to use this
160 feature, <file:Documentation/admin-g 193 feature, <file:Documentation/admin-guide/java.rst> for information about how
161 to include Java support. and <file:D 194 to include Java support. and <file:Documentation/admin-guide/mono.rst> for
162 information about how to include Mon 195 information about how to include Mono-based .NET support.
163 196
164 To use binfmt_misc, you will need to 197 To use binfmt_misc, you will need to mount it:
165 mount binfmt_misc -t binfmt_mi 198 mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc
166 199
167 You may say M here for module suppor 200 You may say M here for module support and later load the module when
168 you have use for it; the module is c 201 you have use for it; the module is called binfmt_misc. If you
169 don't know what to answer at this po 202 don't know what to answer at this point, say Y.
170 203
171 config COREDUMP 204 config COREDUMP
172 bool "Enable core dump support" if EXP 205 bool "Enable core dump support" if EXPERT
173 default y 206 default y
174 help 207 help
175 This option enables support for perf 208 This option enables support for performing core dumps. You almost
176 certainly want to say Y here. Not ne 209 certainly want to say Y here. Not necessary on systems that never
177 need debugging or only ever run flaw 210 need debugging or only ever run flawless code.
178 <<
179 config EXEC_KUNIT_TEST <<
180 bool "Build execve tests" if !KUNIT_AL <<
181 depends on KUNIT=y <<
182 default KUNIT_ALL_TESTS <<
183 help <<
184 This builds the exec KUnit tests, wh <<
185 of various aspects of the exec inter <<
186 211
187 endmenu 212 endmenu
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