4 default "/lib/modules/$UNAME_RELEASE/.config"
5 default "/etc/kernel-config"
6 default "/boot/config-$UNAME_RELEASE"
7 default "arch/$ARCH/defconfig"
9 menu "Code maturity level options"
12 bool "Prompt for development and/or incomplete code/drivers"
14 Some of the various things that Linux supports (such as network
15 drivers, file systems, network protocols, etc.) can be in a state
16 of development where the functionality, stability, or the level of
17 testing is not yet high enough for general use. This is usually
18 known as the "alpha-test" phase among developers. If a feature is
19 currently in alpha-test, then the developers usually discourage
20 uninformed widespread use of this feature by the general public to
21 avoid "Why doesn't this work?" type mail messages. However, active
22 testing and use of these systems is welcomed. Just be aware that it
23 may not meet the normal level of reliability or it may fail to work
24 in some special cases. Detailed bug reports from people familiar
25 with the kernel internals are usually welcomed by the developers
26 (before submitting bug reports, please read the documents
27 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
28 <file:Documentation/BUG-HUNTING>, and
29 <file:Documentation/oops-tracing.txt> in the kernel source).
31 This option will also make obsoleted drivers available. These are
32 drivers that have been replaced by something else, and/or are
33 scheduled to be removed in a future kernel release.
35 Unless you intend to help test and develop a feature or driver that
36 falls into this category, or you have a situation that requires
37 using these features, you should probably say N here, which will
38 cause the configurator to present you with fewer choices. If
39 you say Y here, you will be offered the choice of using features or
40 drivers that are currently considered to be in the alpha-test phase.
47 depends on BROKEN || !SMP
52 depends on SMP || PREEMPT
55 config INIT_ENV_ARG_LIMIT
57 default 32 if !USERMODE
58 default 128 if USERMODE
60 Maximum of each of the number of arguments and environment
61 variables passed to init from the kernel command line.
68 string "Local version - append to kernel release"
70 Append an extra string to the end of your kernel version.
71 This will show up when you type uname, for example.
72 The string you set here will be appended after the contents of
73 any files with a filename matching localversion* in your
74 object and source tree, in that order. Your total string can
75 be a maximum of 64 characters.
77 config LOCALVERSION_AUTO
78 bool "Automatically append version information to the version string"
81 This will try to automatically determine if the current tree is a
82 release tree by looking for git tags that
83 belong to the current top of tree revision.
85 A string of the format -gxxxxxxxx will be added to the localversion
86 if a git based tree is found. The string generated by this will be
87 appended after any matching localversion* files, and after the value
88 set in CONFIG_LOCALVERSION
90 Note: This requires Perl, and a git repository, but not necessarily
91 the git or cogito tools to be installed.
94 bool "Support for paging of anonymous memory (swap)"
98 This option allows you to choose whether you want to have support
99 for so called swap devices or swap files in your kernel that are
100 used to provide more virtual memory than the actual RAM present
101 in your computer. If unsure say Y.
106 Inter Process Communication is a suite of library functions and
107 system calls which let processes (running programs) synchronize and
108 exchange information. It is generally considered to be a good thing,
109 and some programs won't run unless you say Y here. In particular, if
110 you want to run the DOS emulator dosemu under Linux (read the
111 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
112 you'll need to say Y here.
114 You can find documentation about IPC with "info ipc" and also in
115 section 6.4 of the Linux Programmer's Guide, available from
116 <http://www.tldp.org/guides.html>.
119 bool "POSIX Message Queues"
120 depends on NET && EXPERIMENTAL
122 POSIX variant of message queues is a part of IPC. In POSIX message
123 queues every message has a priority which decides about succession
124 of receiving it by a process. If you want to compile and run
125 programs written e.g. for Solaris with use of its POSIX message
126 queues (functions mq_*) say Y here. To use this feature you will
127 also need mqueue library, available from
128 <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
130 POSIX message queues are visible as a filesystem called 'mqueue'
131 and can be mounted somewhere if you want to do filesystem
132 operations on message queues.
136 config BSD_PROCESS_ACCT
137 bool "BSD Process Accounting"
139 If you say Y here, a user level program will be able to instruct the
140 kernel (via a special system call) to write process accounting
141 information to a file: whenever a process exits, information about
142 that process will be appended to the file by the kernel. The
143 information includes things such as creation time, owning user,
144 command name, memory usage, controlling terminal etc. (the complete
145 list is in the struct acct in <file:include/linux/acct.h>). It is
146 up to the user level program to do useful things with this
147 information. This is generally a good idea, so say Y.
149 config BSD_PROCESS_ACCT_V3
150 bool "BSD Process Accounting version 3 file format"
151 depends on BSD_PROCESS_ACCT
154 If you say Y here, the process accounting information is written
155 in a new file format that also logs the process IDs of each
156 process and it's parent. Note that this file format is incompatible
157 with previous v0/v1/v2 file formats, so you will need updated tools
158 for processing it. A preliminary version of these tools is available
159 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
162 bool "Sysctl support"
164 The sysctl interface provides a means of dynamically changing
165 certain kernel parameters and variables on the fly without requiring
166 a recompile of the kernel or reboot of the system. The primary
167 interface consists of a system call, but if you say Y to "/proc
168 file system support", a tree of modifiable sysctl entries will be
169 generated beneath the /proc/sys directory. They are explained in the
170 files in <file:Documentation/sysctl/>. Note that enabling this
171 option will enlarge the kernel by at least 8 KB.
173 As it is generally a good thing, you should say Y here unless
174 building a kernel for install/rescue disks or your system is very
178 bool "Auditing support"
181 Enable auditing infrastructure that can be used with another
182 kernel subsystem, such as SELinux (which requires this for
183 logging of avc messages output). Does not do system-call
184 auditing without CONFIG_AUDITSYSCALL.
187 bool "Enable system-call auditing support"
188 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64)
189 default y if SECURITY_SELINUX
191 Enable low-overhead system-call auditing infrastructure that
192 can be used independently or with another kernel subsystem,
196 bool "Kernel .config support"
198 This option enables the complete Linux kernel ".config" file
199 contents to be saved in the kernel. It provides documentation
200 of which kernel options are used in a running kernel or in an
201 on-disk kernel. This information can be extracted from the kernel
202 image file with the script scripts/extract-ikconfig and used as
203 input to rebuild the current kernel or to build another kernel.
204 It can also be extracted from a running kernel by reading
205 /proc/config.gz if enabled (below).
208 bool "Enable access to .config through /proc/config.gz"
209 depends on IKCONFIG && PROC_FS
211 This option enables access to the kernel configuration file
212 through /proc/config.gz.
215 bool "Cpuset support"
218 This option will let you create and manage CPUSETs which
219 allow dynamically partitioning a system into sets of CPUs and
220 Memory Nodes and assigning tasks to run only within those sets.
221 This is primarily useful on large SMP or NUMA systems.
226 bool "Kernel->user space relay support (formerly relayfs)"
228 This option enables support for relay interface support in
229 certain file systems (such as debugfs).
230 It is designed to provide an efficient mechanism for tools and
231 facilities to relay large amounts of data from kernel space to
239 bool "Enable 16-bit UID system calls" if EMBEDDED
240 depends on ARM || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
243 This enables the legacy 16-bit UID syscall wrappers.
248 bool "Enable VM86 support" if EMBEDDED
250 This option is required by programs like DOSEMU to run 16-bit legacy
251 code on X86 processors. It also may be needed by software like
252 XFree86 to initialize some video cards via BIOS. Disabling this
253 option saves about 6k.
255 config CC_OPTIMIZE_FOR_SIZE
256 bool "Optimize for size (Look out for broken compilers!)"
258 depends on ARM || H8300 || EXPERIMENTAL
260 Enabling this option will pass "-Os" instead of "-O2" to gcc
261 resulting in a smaller kernel.
263 WARNING: some versions of gcc may generate incorrect code with this
264 option. If problems are observed, a gcc upgrade may be needed.
269 bool "Configure standard kernel features (for small systems)"
271 This option allows certain base kernel options and settings
272 to be disabled or tweaked. This is for specialized
273 environments which can tolerate a "non-standard" kernel.
274 Only use this if you really know what you are doing.
277 bool "Load all symbols for debugging/kksymoops" if EMBEDDED
280 Say Y here to let the kernel print out symbolic crash information and
281 symbolic stack backtraces. This increases the size of the kernel
282 somewhat, as all symbols have to be loaded into the kernel image.
285 bool "Include all symbols in kallsyms"
286 depends on DEBUG_KERNEL && KALLSYMS
288 Normally kallsyms only contains the symbols of functions, for nicer
289 OOPS messages. Some debuggers can use kallsyms for other
290 symbols too: say Y here to include all symbols, if you need them
291 and you don't care about adding 300k to the size of your kernel.
295 config KALLSYMS_EXTRA_PASS
296 bool "Do an extra kallsyms pass"
299 If kallsyms is not working correctly, the build will fail with
300 inconsistent kallsyms data. If that occurs, log a bug report and
301 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
302 Always say N here unless you find a bug in kallsyms, which must be
303 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
304 you wait for kallsyms to be fixed.
308 bool "Support for hot-pluggable devices" if EMBEDDED
311 This option is provided for the case where no hotplug or uevent
312 capabilities is wanted by the kernel. You should only consider
313 disabling this option for embedded systems that do not use modules, a
314 dynamic /dev tree, or dynamic device discovery. Just say Y.
318 bool "Enable support for printk" if EMBEDDED
320 This option enables normal printk support. Removing it
321 eliminates most of the message strings from the kernel image
322 and makes the kernel more or less silent. As this makes it
323 very difficult to diagnose system problems, saying N here is
324 strongly discouraged.
327 bool "BUG() support" if EMBEDDED
330 Disabling this option eliminates support for BUG and WARN, reducing
331 the size of your kernel image and potentially quietly ignoring
332 numerous fatal conditions. You should only consider disabling this
333 option for embedded systems with no facilities for reporting errors.
338 bool "Enable ELF core dumps" if EMBEDDED
340 Enable support for generating core dumps. Disabling saves about 4k.
344 bool "Enable full-sized data structures for core" if EMBEDDED
346 Disabling this option reduces the size of miscellaneous core
347 kernel data structures. This saves memory on small machines,
348 but may reduce performance.
351 bool "Enable futex support" if EMBEDDED
354 Disabling this option will cause the kernel to be built without
355 support for "fast userspace mutexes". The resulting kernel may not
356 run glibc-based applications correctly.
359 bool "Enable eventpoll support" if EMBEDDED
362 Disabling this option will cause the kernel to be built without
363 support for epoll family of system calls.
366 bool "Use full shmem filesystem" if EMBEDDED
370 The shmem is an internal filesystem used to manage shared memory.
371 It is backed by swap and manages resource limits. It is also exported
372 to userspace as tmpfs if TMPFS is enabled. Disabling this
373 option replaces shmem and tmpfs with the much simpler ramfs code,
374 which may be appropriate on small systems without swap.
378 bool "Use full SLAB allocator" if EMBEDDED
380 Disabling this replaces the advanced SLAB allocator and
381 kmalloc support with the drastically simpler SLOB allocator.
382 SLOB is more space efficient but does not scale well and is
383 more susceptible to fragmentation.
385 endmenu # General setup
393 default 0 if BASE_FULL
394 default 1 if !BASE_FULL
400 config OBSOLETE_INTERMODULE
403 menu "Loadable module support"
406 bool "Enable loadable module support"
408 Kernel modules are small pieces of compiled code which can
409 be inserted in the running kernel, rather than being
410 permanently built into the kernel. You use the "modprobe"
411 tool to add (and sometimes remove) them. If you say Y here,
412 many parts of the kernel can be built as modules (by
413 answering M instead of Y where indicated): this is most
414 useful for infrequently used options which are not required
415 for booting. For more information, see the man pages for
416 modprobe, lsmod, modinfo, insmod and rmmod.
418 If you say Y here, you will need to run "make
419 modules_install" to put the modules under /lib/modules/
420 where modprobe can find them (you may need to be root to do
426 bool "Module unloading"
429 Without this option you will not be able to unload any
430 modules (note that some modules may not be unloadable
431 anyway), which makes your kernel slightly smaller and
432 simpler. If unsure, say Y.
434 config MODULE_FORCE_UNLOAD
435 bool "Forced module unloading"
436 depends on MODULE_UNLOAD && EXPERIMENTAL
438 This option allows you to force a module to unload, even if the
439 kernel believes it is unsafe: the kernel will remove the module
440 without waiting for anyone to stop using it (using the -f option to
441 rmmod). This is mainly for kernel developers and desperate users.
445 bool "Module versioning support"
448 Usually, you have to use modules compiled with your kernel.
449 Saying Y here makes it sometimes possible to use modules
450 compiled for different kernels, by adding enough information
451 to the modules to (hopefully) spot any changes which would
452 make them incompatible with the kernel you are running. If
455 config MODULE_SRCVERSION_ALL
456 bool "Source checksum for all modules"
459 Modules which contain a MODULE_VERSION get an extra "srcversion"
460 field inserted into their modinfo section, which contains a
461 sum of the source files which made it. This helps maintainers
462 see exactly which source was used to build a module (since
463 others sometimes change the module source without updating
464 the version). With this option, such a "srcversion" field
465 will be created for all modules. If unsure, say N.
468 bool "Automatic kernel module loading"
471 Normally when you have selected some parts of the kernel to
472 be created as kernel modules, you must load them (using the
473 "modprobe" command) before you can use them. If you say Y
474 here, some parts of the kernel will be able to load modules
475 automatically: when a part of the kernel needs a module, it
476 runs modprobe with the appropriate arguments, thereby
477 loading the module if it is available. If unsure, say Y.
482 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
484 Need stop_machine() primitive.
488 source "block/Kconfig"