Based on kernel version 4.16.1. Page generated on 2018-04-09 11:53 EST.
1 This file contains some assistance for using "make *config". 2 3 Use "make help" to list all of the possible configuration targets. 4 5 The xconfig ('qconf') and menuconfig ('mconf') programs also 6 have embedded help text. Be sure to check it for navigation, 7 search, and other general help text. 8 9 ====================================================================== 10 General 11 -------------------------------------------------- 12 13 New kernel releases often introduce new config symbols. Often more 14 important, new kernel releases may rename config symbols. When 15 this happens, using a previously working .config file and running 16 "make oldconfig" won't necessarily produce a working new kernel 17 for you, so you may find that you need to see what NEW kernel 18 symbols have been introduced. 19 20 To see a list of new config symbols when using "make oldconfig", use 21 22 cp user/some/old.config .config 23 make listnewconfig 24 25 and the config program will list any new symbols, one per line. 26 27 scripts/diffconfig .config.old .config | less 28 29 ______________________________________________________________________ 30 Environment variables for '*config' 31 32 KCONFIG_CONFIG 33 -------------------------------------------------- 34 This environment variable can be used to specify a default kernel config 35 file name to override the default name of ".config". 36 37 KCONFIG_OVERWRITECONFIG 38 -------------------------------------------------- 39 If you set KCONFIG_OVERWRITECONFIG in the environment, Kconfig will not 40 break symlinks when .config is a symlink to somewhere else. 41 42 CONFIG_ 43 -------------------------------------------------- 44 If you set CONFIG_ in the environment, Kconfig will prefix all symbols 45 with its value when saving the configuration, instead of using the default, 46 "CONFIG_". 47 48 ______________________________________________________________________ 49 Environment variables for '{allyes/allmod/allno/rand}config' 50 51 KCONFIG_ALLCONFIG 52 -------------------------------------------------- 53 (partially based on lkml email from/by Rob Landley, re: miniconfig) 54 -------------------------------------------------- 55 The allyesconfig/allmodconfig/allnoconfig/randconfig variants can also 56 use the environment variable KCONFIG_ALLCONFIG as a flag or a filename 57 that contains config symbols that the user requires to be set to a 58 specific value. If KCONFIG_ALLCONFIG is used without a filename where 59 KCONFIG_ALLCONFIG == "" or KCONFIG_ALLCONFIG == "1", "make *config" 60 checks for a file named "all{yes/mod/no/def/random}.config" 61 (corresponding to the *config command that was used) for symbol values 62 that are to be forced. If this file is not found, it checks for a 63 file named "all.config" to contain forced values. 64 65 This enables you to create "miniature" config (miniconfig) or custom 66 config files containing just the config symbols that you are interested 67 in. Then the kernel config system generates the full .config file, 68 including symbols of your miniconfig file. 69 70 This 'KCONFIG_ALLCONFIG' file is a config file which contains 71 (usually a subset of all) preset config symbols. These variable 72 settings are still subject to normal dependency checks. 73 74 Examples: 75 KCONFIG_ALLCONFIG=custom-notebook.config make allnoconfig 76 or 77 KCONFIG_ALLCONFIG=mini.config make allnoconfig 78 or 79 make KCONFIG_ALLCONFIG=mini.config allnoconfig 80 81 These examples will disable most options (allnoconfig) but enable or 82 disable the options that are explicitly listed in the specified 83 mini-config files. 84 85 ______________________________________________________________________ 86 Environment variables for 'randconfig' 87 88 KCONFIG_SEED 89 -------------------------------------------------- 90 You can set this to the integer value used to seed the RNG, if you want 91 to somehow debug the behaviour of the kconfig parser/frontends. 92 If not set, the current time will be used. 93 94 KCONFIG_PROBABILITY 95 -------------------------------------------------- 96 This variable can be used to skew the probabilities. This variable can 97 be unset or empty, or set to three different formats: 98 KCONFIG_PROBABILITY y:n split y:m:n split 99 ----------------------------------------------------------------- 100 unset or empty 50 : 50 33 : 33 : 34 101 N N : 100-N N/2 : N/2 : 100-N 102 [1] N:M N+M : 100-(N+M) N : M : 100-(N+M) 103 [2] N:M:L N : 100-N M : L : 100-(M+L) 104 105 where N, M and L are integers (in base 10) in the range [0,100], and so 106 that: 107 [1] N+M is in the range [0,100] 108 [2] M+L is in the range [0,100] 109 110 Examples: 111 KCONFIG_PROBABILITY=10 112 10% of booleans will be set to 'y', 90% to 'n' 113 5% of tristates will be set to 'y', 5% to 'm', 90% to 'n' 114 KCONFIG_PROBABILITY=15:25 115 40% of booleans will be set to 'y', 60% to 'n' 116 15% of tristates will be set to 'y', 25% to 'm', 60% to 'n' 117 KCONFIG_PROBABILITY=10:15:15 118 10% of booleans will be set to 'y', 90% to 'n' 119 15% of tristates will be set to 'y', 15% to 'm', 70% to 'n' 120 121 ______________________________________________________________________ 122 Environment variables for 'silentoldconfig' 123 124 KCONFIG_NOSILENTUPDATE 125 -------------------------------------------------- 126 If this variable has a non-blank value, it prevents silent kernel 127 config updates (requires explicit updates). 128 129 KCONFIG_AUTOCONFIG 130 -------------------------------------------------- 131 This environment variable can be set to specify the path & name of the 132 "auto.conf" file. Its default value is "include/config/auto.conf". 133 134 KCONFIG_TRISTATE 135 -------------------------------------------------- 136 This environment variable can be set to specify the path & name of the 137 "tristate.conf" file. Its default value is "include/config/tristate.conf". 138 139 KCONFIG_AUTOHEADER 140 -------------------------------------------------- 141 This environment variable can be set to specify the path & name of the 142 "autoconf.h" (header) file. 143 Its default value is "include/generated/autoconf.h". 144 145 146 ====================================================================== 147 menuconfig 148 -------------------------------------------------- 149 150 SEARCHING for CONFIG symbols 151 152 Searching in menuconfig: 153 154 The Search function searches for kernel configuration symbol 155 names, so you have to know something close to what you are 156 looking for. 157 158 Example: 159 /hotplug 160 This lists all config symbols that contain "hotplug", 161 e.g., HOTPLUG_CPU, MEMORY_HOTPLUG. 162 163 For search help, enter / followed TAB-TAB-TAB (to highlight 164 <Help>) and Enter. This will tell you that you can also use 165 regular expressions (regexes) in the search string, so if you 166 are not interested in MEMORY_HOTPLUG, you could try 167 168 /^hotplug 169 170 When searching, symbols are sorted thus: 171 - first, exact matches, sorted alphabetically (an exact match 172 is when the search matches the complete symbol name); 173 - then, other matches, sorted alphabetically. 174 For example: ^ATH.K matches: 175 ATH5K ATH9K ATH5K_AHB ATH5K_DEBUG [...] ATH6KL ATH6KL_DEBUG 176 [...] ATH9K_AHB ATH9K_BTCOEX_SUPPORT ATH9K_COMMON [...] 177 of which only ATH5K and ATH9K match exactly and so are sorted 178 first (and in alphabetical order), then come all other symbols, 179 sorted in alphabetical order. 180 181 ______________________________________________________________________ 182 User interface options for 'menuconfig' 183 184 MENUCONFIG_COLOR 185 -------------------------------------------------- 186 It is possible to select different color themes using the variable 187 MENUCONFIG_COLOR. To select a theme use: 188 189 make MENUCONFIG_COLOR=<theme> menuconfig 190 191 Available themes are: 192 mono => selects colors suitable for monochrome displays 193 blackbg => selects a color scheme with black background 194 classic => theme with blue background. The classic look 195 bluetitle => a LCD friendly version of classic. (default) 196 197 MENUCONFIG_MODE 198 -------------------------------------------------- 199 This mode shows all sub-menus in one large tree. 200 201 Example: 202 make MENUCONFIG_MODE=single_menu menuconfig 203 204 205 ====================================================================== 206 xconfig 207 -------------------------------------------------- 208 209 Searching in xconfig: 210 211 The Search function searches for kernel configuration symbol 212 names, so you have to know something close to what you are 213 looking for. 214 215 Example: 216 Ctrl-F hotplug 217 or 218 Menu: File, Search, hotplug 219 220 lists all config symbol entries that contain "hotplug" in 221 the symbol name. In this Search dialog, you may change the 222 config setting for any of the entries that are not grayed out. 223 You can also enter a different search string without having 224 to return to the main menu. 225 226 227 ====================================================================== 228 gconfig 229 -------------------------------------------------- 230 231 Searching in gconfig: 232 233 None (gconfig isn't maintained as well as xconfig or menuconfig); 234 however, gconfig does have a few more viewing choices than 235 xconfig does. 236 237 ###