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 <<
32 bool "Build KUnit tests for ELF binary <<
33 depends on KUNIT=y && BINFMT_ELF=y <<
34 default KUNIT_ALL_TESTS <<
35 help <<
36 This builds the ELF loader KUnit tes <<
37 prior bug fixes into a regression te <<
38 only needed for debugging. Note that <<
39 compat_binfmt_elf KUnit test is also <<
40 <<
41 config COMPAT_BINFMT_ELF 31 config COMPAT_BINFMT_ELF
42 def_bool y !! 32 bool
43 depends on COMPAT && BINFMT_ELF 33 depends on COMPAT && BINFMT_ELF
44 select ELFCORE 34 select ELFCORE
45 35
46 config ARCH_BINFMT_ELF_STATE 36 config ARCH_BINFMT_ELF_STATE
47 bool 37 bool
48 38
49 config ARCH_BINFMT_ELF_EXTRA_PHDRS <<
50 bool <<
51 <<
52 config ARCH_HAVE_ELF_PROT <<
53 bool <<
54 <<
55 config ARCH_USE_GNU_PROPERTY <<
56 bool <<
57 <<
58 config BINFMT_ELF_FDPIC 39 config BINFMT_ELF_FDPIC
59 bool "Kernel support for FDPIC ELF bin 40 bool "Kernel support for FDPIC ELF binaries"
60 default y if !BINFMT_ELF 41 default y if !BINFMT_ELF
61 depends on ARM || ((M68K || RISCV || S !! 42 depends on (ARM || (SUPERH32 && !MMU) || C6X)
62 select ELFCORE 43 select ELFCORE
63 help 44 help
64 ELF FDPIC binaries are based on ELF, 45 ELF FDPIC binaries are based on ELF, but allow the individual load
65 segments of a binary to be located i 46 segments of a binary to be located in memory independently of each
66 other. This makes this format ideal 47 other. This makes this format ideal for use in environments where no
67 MMU is available as it still permits 48 MMU is available as it still permits text segments to be shared,
68 even if data segments are not. 49 even if data segments are not.
69 50
70 It is also possible to run FDPIC ELF 51 It is also possible to run FDPIC ELF binaries on MMU linux also.
71 52
72 config ELFCORE 53 config ELFCORE
73 bool 54 bool
74 help 55 help
75 This option enables kernel/elfcore.o 56 This option enables kernel/elfcore.o.
76 57
77 config CORE_DUMP_DEFAULT_ELF_HEADERS 58 config CORE_DUMP_DEFAULT_ELF_HEADERS
78 bool "Write ELF core dumps with partia 59 bool "Write ELF core dumps with partial segments"
79 default y 60 default y
80 depends on BINFMT_ELF && ELF_CORE 61 depends on BINFMT_ELF && ELF_CORE
81 help 62 help
82 ELF core dump files describe each me 63 ELF core dump files describe each memory mapping of the crashed
83 process, and can contain or omit the 64 process, and can contain or omit the memory contents of each one.
84 The contents of an unmodified text m 65 The contents of an unmodified text mapping are omitted by default.
85 66
86 For an unmodified text mapping of an 67 For an unmodified text mapping of an ELF object, including just
87 the first page of the file in a core 68 the first page of the file in a core dump makes it possible to
88 identify the build ID bits in the fi 69 identify the build ID bits in the file, without paying the i/o
89 cost and disk space to dump all the 70 cost and disk space to dump all the text. However, versions of
90 GDB before 6.7 are confused by ELF c 71 GDB before 6.7 are confused by ELF core dump files in this format.
91 72
92 The core dump behavior can be contro 73 The core dump behavior can be controlled per process using
93 the /proc/PID/coredump_filter pseudo 74 the /proc/PID/coredump_filter pseudo-file; this setting is
94 inherited. See Documentation/filesy !! 75 inherited. See Documentation/filesystems/proc.txt for details.
95 76
96 This config option changes the defau 77 This config option changes the default setting of coredump_filter
97 seen at boot time. If unsure, say Y 78 seen at boot time. If unsure, say Y.
98 79
99 config BINFMT_SCRIPT 80 config BINFMT_SCRIPT
100 tristate "Kernel support for scripts s 81 tristate "Kernel support for scripts starting with #!"
101 default y 82 default y
102 help 83 help
103 Say Y here if you want to execute in 84 Say Y here if you want to execute interpreted scripts starting with
104 #! followed by the path to an interp 85 #! followed by the path to an interpreter.
105 86
106 You can build this support as a modu 87 You can build this support as a module; however, until that module
107 gets loaded, you cannot run scripts. 88 gets loaded, you cannot run scripts. Thus, if you want to load this
108 module from an initramfs, the portio 89 module from an initramfs, the portion of the initramfs before loading
109 this module must consist of compiled 90 this module must consist of compiled binaries only.
110 91
111 Most systems will not boot if you sa 92 Most systems will not boot if you say M or N here. If unsure, say Y.
112 93
113 config ARCH_HAS_BINFMT_FLAT <<
114 bool <<
115 <<
116 config BINFMT_FLAT 94 config BINFMT_FLAT
117 bool "Kernel support for flat binaries 95 bool "Kernel support for flat binaries"
118 depends on ARCH_HAS_BINFMT_FLAT !! 96 depends on !MMU || ARM || M68K
119 help 97 help
120 Support uClinux FLAT format binaries 98 Support uClinux FLAT format binaries.
121 99
122 config BINFMT_FLAT_ARGVP_ENVP_ON_STACK <<
123 bool <<
124 <<
125 config BINFMT_FLAT_OLD_ALWAYS_RAM <<
126 bool <<
127 <<
128 config BINFMT_FLAT_NO_DATA_START_OFFSET <<
129 bool <<
130 <<
131 config BINFMT_FLAT_OLD <<
132 bool "Enable support for very old lega <<
133 depends on BINFMT_FLAT <<
134 help <<
135 Support decade old uClinux FLAT form <<
136 you have some of those say N here. <<
137 <<
138 config BINFMT_ZFLAT 100 config BINFMT_ZFLAT
139 bool "Enable ZFLAT support" 101 bool "Enable ZFLAT support"
140 depends on BINFMT_FLAT 102 depends on BINFMT_FLAT
141 select ZLIB_INFLATE 103 select ZLIB_INFLATE
142 help 104 help
143 Support FLAT format compressed binar 105 Support FLAT format compressed binaries
144 106
>> 107 config BINFMT_SHARED_FLAT
>> 108 bool "Enable shared FLAT support"
>> 109 depends on BINFMT_FLAT
>> 110 help
>> 111 Support FLAT shared libraries
>> 112
>> 113 config HAVE_AOUT
>> 114 def_bool n
>> 115
>> 116 config BINFMT_AOUT
>> 117 tristate "Kernel support for a.out and ECOFF binaries"
>> 118 depends on HAVE_AOUT
>> 119 ---help---
>> 120 A.out (Assembler.OUTput) is a set of formats for libraries and
>> 121 executables used in the earliest versions of UNIX. Linux used
>> 122 the a.out formats QMAGIC and ZMAGIC until they were replaced
>> 123 with the ELF format.
>> 124
>> 125 The conversion to ELF started in 1995. This option is primarily
>> 126 provided for historical interest and for the benefit of those
>> 127 who need to run binaries from that era.
>> 128
>> 129 Most people should answer N here. If you think you may have
>> 130 occasional use for this format, enable module support above
>> 131 and answer M here to compile this support as a module called
>> 132 binfmt_aout.
>> 133
>> 134 If any crucial components of your system (such as /sbin/init
>> 135 or /lib/ld.so) are still in a.out format, you will have to
>> 136 say Y here.
>> 137
>> 138 config OSF4_COMPAT
>> 139 bool "OSF/1 v4 readv/writev compatibility"
>> 140 depends on ALPHA && BINFMT_AOUT
>> 141 help
>> 142 Say Y if you are using OSF/1 binaries (like Netscape and Acrobat)
>> 143 with v4 shared libraries freely available from Compaq. If you're
>> 144 going to use shared libraries from Tru64 version 5.0 or later, say N.
>> 145
>> 146 config BINFMT_EM86
>> 147 tristate "Kernel support for Linux/Intel ELF binaries"
>> 148 depends on ALPHA
>> 149 ---help---
>> 150 Say Y here if you want to be able to execute Linux/Intel ELF
>> 151 binaries just like native Alpha binaries on your Alpha machine. For
>> 152 this to work, you need to have the emulator /usr/bin/em86 in place.
>> 153
>> 154 You can get the same functionality by saying N here and saying Y to
>> 155 "Kernel support for MISC binaries".
>> 156
>> 157 You may answer M to compile the emulation support as a module and
>> 158 later load the module when you want to use a Linux/Intel binary. The
>> 159 module will be called binfmt_em86. If unsure, say Y.
>> 160
145 config BINFMT_MISC 161 config BINFMT_MISC
146 tristate "Kernel support for MISC bina 162 tristate "Kernel support for MISC binaries"
147 help !! 163 ---help---
148 If you say Y here, it will be possib 164 If you say Y here, it will be possible to plug wrapper-driven binary
149 formats into the kernel. You will li 165 formats into the kernel. You will like this especially when you use
150 programs that need an interpreter to 166 programs that need an interpreter to run like Java, Python, .NET or
151 Emacs-Lisp. It's also useful if you 167 Emacs-Lisp. It's also useful if you often run DOS executables under
152 the Linux DOS emulator DOSEMU (read 168 the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from
153 <http://www.tldp.org/docs.html#howto 169 <http://www.tldp.org/docs.html#howto>). Once you have
154 registered such a binary class with 170 registered such a binary class with the kernel, you can start one of
155 those programs simply by typing in i 171 those programs simply by typing in its name at a shell prompt; Linux
156 will automatically feed it to the co 172 will automatically feed it to the correct interpreter.
157 173
158 You can do other nice things, too. R 174 You can do other nice things, too. Read the file
159 <file:Documentation/admin-guide/binf 175 <file:Documentation/admin-guide/binfmt-misc.rst> to learn how to use this
160 feature, <file:Documentation/admin-g 176 feature, <file:Documentation/admin-guide/java.rst> for information about how
161 to include Java support. and <file:D 177 to include Java support. and <file:Documentation/admin-guide/mono.rst> for
162 information about how to include Mon 178 information about how to include Mono-based .NET support.
163 179
164 To use binfmt_misc, you will need to 180 To use binfmt_misc, you will need to mount it:
165 mount binfmt_misc -t binfmt_mi 181 mount binfmt_misc -t binfmt_misc /proc/sys/fs/binfmt_misc
166 182
167 You may say M here for module suppor 183 You may say M here for module support and later load the module when
168 you have use for it; the module is c 184 you have use for it; the module is called binfmt_misc. If you
169 don't know what to answer at this po 185 don't know what to answer at this point, say Y.
170 186
171 config COREDUMP 187 config COREDUMP
172 bool "Enable core dump support" if EXP 188 bool "Enable core dump support" if EXPERT
173 default y 189 default y
174 help 190 help
175 This option enables support for perf 191 This option enables support for performing core dumps. You almost
176 certainly want to say Y here. Not ne 192 certainly want to say Y here. Not necessary on systems that never
177 need debugging or only ever run flaw 193 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 <<
186 194
187 endmenu 195 endmenu
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