1 menu "Code maturity level options"
4 bool "Prompt for development and/or incomplete code/drivers"
6 Some of the various things that Linux supports (such as network
7 drivers, file systems, network protocols, etc.) can be in a state
8 of development where the functionality, stability, or the level of
9 testing is not yet high enough for general use. This is usually
10 known as the "alpha-test" phase among developers. If a feature is
11 currently in alpha-test, then the developers usually discourage
12 uninformed widespread use of this feature by the general public to
13 avoid "Why doesn't this work?" type mail messages. However, active
14 testing and use of these systems is welcomed. Just be aware that it
15 may not meet the normal level of reliability or it may fail to work
16 in some special cases. Detailed bug reports from people familiar
17 with the kernel internals are usually welcomed by the developers
18 (before submitting bug reports, please read the documents
19 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
20 <file:Documentation/BUG-HUNTING>, and
21 <file:Documentation/oops-tracing.txt> in the kernel source).
23 This option will also make obsoleted drivers available. These are
24 drivers that have been replaced by something else, and/or are
25 scheduled to be removed in a future kernel release.
27 Unless you intend to help test and develop a feature or driver that
28 falls into this category, or you have a situation that requires
29 using these features, you should probably say N here, which will
30 cause the configurator to present you with fewer choices. If
31 you say Y here, you will be offered the choice of using features or
32 drivers that are currently considered to be in the alpha-test phase.
35 bool "Select only drivers expected to compile cleanly" if EXPERIMENTAL
38 Select this option if you don't even want to see the option
39 to configure known-broken drivers.
45 depends on !CLEAN_COMPILE
50 depends on BROKEN || !SMP
55 depends on SMP || PREEMPT
58 config INIT_ENV_ARG_LIMIT
60 default 32 if !USERMODE
61 default 128 if USERMODE
63 Maximum of each of the number of arguments and environment
64 variables passed to init from the kernel command line.
71 string "Local version - append to kernel release"
73 Append an extra string to the end of your kernel version.
74 This will show up when you type uname, for example.
75 The string you set here will be appended after the contents of
76 any files with a filename matching localversion* in your
77 object and source tree, in that order. Your total string can
78 be a maximum of 64 characters.
80 config LOCALVERSION_AUTO
81 bool "Automatically append version information to the version string"
84 This will try to automatically determine if the current tree is a
85 release tree by looking for git tags that
86 belong to the current top of tree revision.
88 A string of the format -gxxxxxxxx will be added to the localversion
89 if a git based tree is found. The string generated by this will be
90 appended after any matching localversion* files, and after the value
91 set in CONFIG_LOCALVERSION
93 Note: This requires Perl, and a git repository, but not necessarily
94 the git or cogito tools to be installed.
97 bool "Support for paging of anonymous memory (swap)"
101 This option allows you to choose whether you want to have support
102 for socalled swap devices or swap files in your kernel that are
103 used to provide more virtual memory than the actual RAM present
104 in your computer. If unsure say Y.
110 Inter Process Communication is a suite of library functions and
111 system calls which let processes (running programs) synchronize and
112 exchange information. It is generally considered to be a good thing,
113 and some programs won't run unless you say Y here. In particular, if
114 you want to run the DOS emulator dosemu under Linux (read the
115 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
116 you'll need to say Y here.
118 You can find documentation about IPC with "info ipc" and also in
119 section 6.4 of the Linux Programmer's Guide, available from
120 <http://www.tldp.org/guides.html>.
123 bool "POSIX Message Queues"
124 depends on NET && EXPERIMENTAL
126 POSIX variant of message queues is a part of IPC. In POSIX message
127 queues every message has a priority which decides about succession
128 of receiving it by a process. If you want to compile and run
129 programs written e.g. for Solaris with use of its POSIX message
130 queues (functions mq_*) say Y here. To use this feature you will
131 also need mqueue library, available from
132 <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
134 POSIX message queues are visible as a filesystem called 'mqueue'
135 and can be mounted somewhere if you want to do filesystem
136 operations on message queues.
140 config BSD_PROCESS_ACCT
141 bool "BSD Process Accounting"
143 If you say Y here, a user level program will be able to instruct the
144 kernel (via a special system call) to write process accounting
145 information to a file: whenever a process exits, information about
146 that process will be appended to the file by the kernel. The
147 information includes things such as creation time, owning user,
148 command name, memory usage, controlling terminal etc. (the complete
149 list is in the struct acct in <file:include/linux/acct.h>). It is
150 up to the user level program to do useful things with this
151 information. This is generally a good idea, so say Y.
153 config BSD_PROCESS_ACCT_V3
154 bool "BSD Process Accounting version 3 file format"
155 depends on BSD_PROCESS_ACCT
158 If you say Y here, the process accounting information is written
159 in a new file format that also logs the process IDs of each
160 process and it's parent. Note that this file format is incompatible
161 with previous v0/v1/v2 file formats, so you will need updated tools
162 for processing it. A preliminary version of these tools is available
163 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
166 bool "Sysctl support"
168 The sysctl interface provides a means of dynamically changing
169 certain kernel parameters and variables on the fly without requiring
170 a recompile of the kernel or reboot of the system. The primary
171 interface consists of a system call, but if you say Y to "/proc
172 file system support", a tree of modifiable sysctl entries will be
173 generated beneath the /proc/sys directory. They are explained in the
174 files in <file:Documentation/sysctl/>. Note that enabling this
175 option will enlarge the kernel by at least 8 KB.
177 As it is generally a good thing, you should say Y here unless
178 building a kernel for install/rescue disks or your system is very
182 bool "Auditing support"
184 default y if SECURITY_SELINUX
186 Enable auditing infrastructure that can be used with another
187 kernel subsystem, such as SELinux (which requires this for
188 logging of avc messages output). Does not do system-call
189 auditing without CONFIG_AUDITSYSCALL.
192 bool "Enable system-call auditing support"
193 depends on AUDIT && (X86 || PPC || PPC64 || ARCH_S390 || IA64 || UML || SPARC64)
194 default y if SECURITY_SELINUX
196 Enable low-overhead system-call auditing infrastructure that
197 can be used independently or with another kernel subsystem,
201 bool "Kernel .config support"
203 This option enables the complete Linux kernel ".config" file
204 contents to be saved in the kernel. It provides documentation
205 of which kernel options are used in a running kernel or in an
206 on-disk kernel. This information can be extracted from the kernel
207 image file with the script scripts/extract-ikconfig and used as
208 input to rebuild the current kernel or to build another kernel.
209 It can also be extracted from a running kernel by reading
210 /proc/config.gz if enabled (below).
213 bool "Enable access to .config through /proc/config.gz"
214 depends on IKCONFIG && PROC_FS
216 This option enables access to the kernel configuration file
217 through /proc/config.gz.
220 bool "Cpuset support"
223 This option will let you create and manage CPUSETs which
224 allow dynamically partitioning a system into sets of CPUs and
225 Memory Nodes and assigning tasks to run only within those sets.
226 This is primarily useful on large SMP or NUMA systems.
232 config CC_OPTIMIZE_FOR_SIZE
233 bool "Optimize for size (Look out for broken compilers!)"
235 depends on ARM || H8300 || EXPERIMENTAL
237 Enabling this option will pass "-Os" instead of "-O2" to gcc
238 resulting in a smaller kernel.
240 WARNING: some versions of gcc may generate incorrect code with this
241 option. If problems are observed, a gcc upgrade may be needed.
246 bool "Configure standard kernel features (for small systems)"
248 This option allows certain base kernel options and settings
249 to be disabled or tweaked. This is for specialized
250 environments which can tolerate a "non-standard" kernel.
251 Only use this if you really know what you are doing.
254 bool "Load all symbols for debugging/kksymoops" if EMBEDDED
257 Say Y here to let the kernel print out symbolic crash information and
258 symbolic stack backtraces. This increases the size of the kernel
259 somewhat, as all symbols have to be loaded into the kernel image.
262 bool "Include all symbols in kallsyms"
263 depends on DEBUG_KERNEL && KALLSYMS
265 Normally kallsyms only contains the symbols of functions, for nicer
266 OOPS messages. Some debuggers can use kallsyms for other
267 symbols too: say Y here to include all symbols, if you need them
268 and you don't care about adding 300k to the size of your kernel.
272 config KALLSYMS_EXTRA_PASS
273 bool "Do an extra kallsyms pass"
276 If kallsyms is not working correctly, the build will fail with
277 inconsistent kallsyms data. If that occurs, log a bug report and
278 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
279 Always say N here unless you find a bug in kallsyms, which must be
280 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
281 you wait for kallsyms to be fixed.
285 bool "Support for hot-pluggable devices" if EMBEDDED
288 This option is provided for the case where no hotplug or uevent
289 capabilities is wanted by the kernel. You should only consider
290 disabling this option for embedded systems that do not use modules, a
291 dynamic /dev tree, or dynamic device discovery. Just say Y.
295 bool "Enable support for printk" if EMBEDDED
297 This option enables normal printk support. Removing it
298 eliminates most of the message strings from the kernel image
299 and makes the kernel more or less silent. As this makes it
300 very difficult to diagnose system problems, saying N here is
301 strongly discouraged.
304 bool "BUG() support" if EMBEDDED
307 Disabling this option eliminates support for BUG and WARN, reducing
308 the size of your kernel image and potentially quietly ignoring
309 numerous fatal conditions. You should only consider disabling this
310 option for embedded systems with no facilities for reporting errors.
315 bool "Enable full-sized data structures for core" if EMBEDDED
317 Disabling this option reduces the size of miscellaneous core
318 kernel data structures. This saves memory on small machines,
319 but may reduce performance.
322 bool "Enable futex support" if EMBEDDED
325 Disabling this option will cause the kernel to be built without
326 support for "fast userspace mutexes". The resulting kernel may not
327 run glibc-based applications correctly.
330 bool "Enable eventpoll support" if EMBEDDED
333 Disabling this option will cause the kernel to be built without
334 support for epoll family of system calls.
337 bool "Use full shmem filesystem" if EMBEDDED
341 The shmem is an internal filesystem used to manage shared memory.
342 It is backed by swap and manages resource limits. It is also exported
343 to userspace as tmpfs if TMPFS is enabled. Disabling this
344 option replaces shmem and tmpfs with the much simpler ramfs code,
345 which may be appropriate on small systems without swap.
347 config CC_ALIGN_FUNCTIONS
348 int "Function alignment" if EMBEDDED
351 Align the start of functions to the next power-of-two greater than n,
352 skipping up to n bytes. For instance, 32 aligns functions
353 to the next 32-byte boundary, but 24 would align to the next
354 32-byte boundary only if this can be done by skipping 23 bytes or less.
355 Zero means use compiler's default.
357 config CC_ALIGN_LABELS
358 int "Label alignment" if EMBEDDED
361 Align all branch targets to a power-of-two boundary, skipping
362 up to n bytes like ALIGN_FUNCTIONS. This option can easily
363 make code slower, because it must insert dummy operations for
364 when the branch target is reached in the usual flow of the code.
365 Zero means use compiler's default.
367 config CC_ALIGN_LOOPS
368 int "Loop alignment" if EMBEDDED
371 Align loops to a power-of-two boundary, skipping up to n bytes.
372 Zero means use compiler's default.
374 config CC_ALIGN_JUMPS
375 int "Jump alignment" if EMBEDDED
378 Align branch targets to a power-of-two boundary, for branch
379 targets where the targets can only be reached by jumping,
380 skipping up to n bytes like ALIGN_FUNCTIONS. In this case,
381 no dummy operations need be executed.
382 Zero means use compiler's default.
384 endmenu # General setup
392 default 0 if BASE_FULL
393 default 1 if !BASE_FULL
395 menu "Loadable module support"
398 bool "Enable loadable module support"
400 Kernel modules are small pieces of compiled code which can
401 be inserted in the running kernel, rather than being
402 permanently built into the kernel. You use the "modprobe"
403 tool to add (and sometimes remove) them. If you say Y here,
404 many parts of the kernel can be built as modules (by
405 answering M instead of Y where indicated): this is most
406 useful for infrequently used options which are not required
407 for booting. For more information, see the man pages for
408 modprobe, lsmod, modinfo, insmod and rmmod.
410 If you say Y here, you will need to run "make
411 modules_install" to put the modules under /lib/modules/
412 where modprobe can find them (you may need to be root to do
418 bool "Module unloading"
421 Without this option you will not be able to unload any
422 modules (note that some modules may not be unloadable
423 anyway), which makes your kernel slightly smaller and
424 simpler. If unsure, say Y.
426 config MODULE_FORCE_UNLOAD
427 bool "Forced module unloading"
428 depends on MODULE_UNLOAD && EXPERIMENTAL
430 This option allows you to force a module to unload, even if the
431 kernel believes it is unsafe: the kernel will remove the module
432 without waiting for anyone to stop using it (using the -f option to
433 rmmod). This is mainly for kernel developers and desperate users.
436 config OBSOLETE_MODPARM
441 You need this option to use module parameters on modules which
442 have not been converted to the new module parameter system yet.
446 bool "Module versioning support"
449 Usually, you have to use modules compiled with your kernel.
450 Saying Y here makes it sometimes possible to use modules
451 compiled for different kernels, by adding enough information
452 to the modules to (hopefully) spot any changes which would
453 make them incompatible with the kernel you are running. If
456 config MODULE_SRCVERSION_ALL
457 bool "Source checksum for all modules"
460 Modules which contain a MODULE_VERSION get an extra "srcversion"
461 field inserted into their modinfo section, which contains a
462 sum of the source files which made it. This helps maintainers
463 see exactly which source was used to build a module (since
464 others sometimes change the module source without updating
465 the version). With this option, such a "srcversion" field
466 will be created for all modules. If unsure, say N.
469 bool "Automatic kernel module loading"
472 Normally when you have selected some parts of the kernel to
473 be created as kernel modules, you must load them (using the
474 "modprobe" command) before you can use them. If you say Y
475 here, some parts of the kernel will be able to load modules
476 automatically: when a part of the kernel needs a module, it
477 runs modprobe with the appropriate arguments, thereby
478 loading the module if it is available. If unsure, say Y.
483 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
485 Need stop_machine() primitive.
489 source "block/Kconfig"
projects / linux-2.6 / blob