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Linus Torvalds1da177e2005-04-16 15:20:36 -07001menu "Code maturity level options"
2
3config EXPERIMENTAL
4 bool "Prompt for development and/or incomplete code/drivers"
5 ---help---
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).
22
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24 drivers that have been replaced by something else, and/or are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.
26
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.
33
34config CLEAN_COMPILE
35 bool "Select only drivers expected to compile cleanly" if EXPERIMENTAL
36 default y
37 help
38 Select this option if you don't even want to see the option
39 to configure known-broken drivers.
40
41 If unsure, say Y
42
43config BROKEN
44 bool
45 depends on !CLEAN_COMPILE
46 default y
47
48config BROKEN_ON_SMP
49 bool
50 depends on BROKEN || !SMP
51 default y
52
53config LOCK_KERNEL
54 bool
55 depends on SMP || PREEMPT
56 default y
57
58config INIT_ENV_ARG_LIMIT
59 int
60 default 32 if !USERMODE
61 default 128 if USERMODE
62 help
Randy Dunlap34ad92c22005-10-30 15:01:46 -080063 Maximum of each of the number of arguments and environment
64 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070065
66endmenu
67
68menu "General setup"
69
70config LOCALVERSION
71 string "Local version - append to kernel release"
72 help
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.
79
Ryan Andersonaaebf432005-07-31 04:57:49 -040080config LOCALVERSION_AUTO
81 bool "Automatically append version information to the version string"
82 default y
83 help
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.
87
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
92
93 Note: This requires Perl, and a git repository, but not necessarily
94 the git or cogito tools to be installed.
95
Linus Torvalds1da177e2005-04-16 15:20:36 -070096config SWAP
97 bool "Support for paging of anonymous memory (swap)"
98 depends on MMU
99 default y
100 help
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.
105
106config SYSVIPC
107 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 ---help---
109 Inter Process Communication is a suite of library functions and
110 system calls which let processes (running programs) synchronize and
111 exchange information. It is generally considered to be a good thing,
112 and some programs won't run unless you say Y here. In particular, if
113 you want to run the DOS emulator dosemu under Linux (read the
114 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
115 you'll need to say Y here.
116
117 You can find documentation about IPC with "info ipc" and also in
118 section 6.4 of the Linux Programmer's Guide, available from
119 <http://www.tldp.org/guides.html>.
120
121config POSIX_MQUEUE
122 bool "POSIX Message Queues"
123 depends on NET && EXPERIMENTAL
124 ---help---
125 POSIX variant of message queues is a part of IPC. In POSIX message
126 queues every message has a priority which decides about succession
127 of receiving it by a process. If you want to compile and run
128 programs written e.g. for Solaris with use of its POSIX message
129 queues (functions mq_*) say Y here. To use this feature you will
130 also need mqueue library, available from
131 <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
132
133 POSIX message queues are visible as a filesystem called 'mqueue'
134 and can be mounted somewhere if you want to do filesystem
135 operations on message queues.
136
137 If unsure, say Y.
138
139config BSD_PROCESS_ACCT
140 bool "BSD Process Accounting"
141 help
142 If you say Y here, a user level program will be able to instruct the
143 kernel (via a special system call) to write process accounting
144 information to a file: whenever a process exits, information about
145 that process will be appended to the file by the kernel. The
146 information includes things such as creation time, owning user,
147 command name, memory usage, controlling terminal etc. (the complete
148 list is in the struct acct in <file:include/linux/acct.h>). It is
149 up to the user level program to do useful things with this
150 information. This is generally a good idea, so say Y.
151
152config BSD_PROCESS_ACCT_V3
153 bool "BSD Process Accounting version 3 file format"
154 depends on BSD_PROCESS_ACCT
155 default n
156 help
157 If you say Y here, the process accounting information is written
158 in a new file format that also logs the process IDs of each
159 process and it's parent. Note that this file format is incompatible
160 with previous v0/v1/v2 file formats, so you will need updated tools
161 for processing it. A preliminary version of these tools is available
162 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
163
164config SYSCTL
165 bool "Sysctl support"
166 ---help---
167 The sysctl interface provides a means of dynamically changing
168 certain kernel parameters and variables on the fly without requiring
169 a recompile of the kernel or reboot of the system. The primary
170 interface consists of a system call, but if you say Y to "/proc
171 file system support", a tree of modifiable sysctl entries will be
172 generated beneath the /proc/sys directory. They are explained in the
173 files in <file:Documentation/sysctl/>. Note that enabling this
174 option will enlarge the kernel by at least 8 KB.
175
176 As it is generally a good thing, you should say Y here unless
177 building a kernel for install/rescue disks or your system is very
178 limited in memory.
179
180config AUDIT
181 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100182 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 default y if SECURITY_SELINUX
184 help
185 Enable auditing infrastructure that can be used with another
186 kernel subsystem, such as SELinux (which requires this for
187 logging of avc messages output). Does not do system-call
188 auditing without CONFIG_AUDITSYSCALL.
189
190config AUDITSYSCALL
191 bool "Enable system-call auditing support"
Martin Schwidefsky347a8dc2006-01-06 00:19:28 -0800192 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 default y if SECURITY_SELINUX
194 help
195 Enable low-overhead system-call auditing infrastructure that
196 can be used independently or with another kernel subsystem,
197 such as SELinux.
198
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199config IKCONFIG
200 bool "Kernel .config support"
201 ---help---
202 This option enables the complete Linux kernel ".config" file
203 contents to be saved in the kernel. It provides documentation
204 of which kernel options are used in a running kernel or in an
205 on-disk kernel. This information can be extracted from the kernel
206 image file with the script scripts/extract-ikconfig and used as
207 input to rebuild the current kernel or to build another kernel.
208 It can also be extracted from a running kernel by reading
209 /proc/config.gz if enabled (below).
210
211config IKCONFIG_PROC
212 bool "Enable access to .config through /proc/config.gz"
213 depends on IKCONFIG && PROC_FS
214 ---help---
215 This option enables access to the kernel configuration file
216 through /proc/config.gz.
217
218config CPUSETS
219 bool "Cpuset support"
220 depends on SMP
221 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700222 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700223 allow dynamically partitioning a system into sets of CPUs and
224 Memory Nodes and assigning tasks to run only within those sets.
225 This is primarily useful on large SMP or NUMA systems.
226
227 Say N if unsure.
228
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200229source "usr/Kconfig"
230
Matt Mackalle585e472006-01-08 01:05:24 -0800231config UID16
232 bool "Enable 16-bit UID system calls" if EMBEDDED
233 depends !ALPHA && !PPC && !PPC64 && !PARISC && !V850 && !ARCH_S390X
234 depends !X86_64 || IA32_EMULATION
235 depends !SPARC64 || SPARC32_COMPAT
236 default y
237 help
238 This enables the legacy 16-bit UID syscall wrappers.
239
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800240config CC_OPTIMIZE_FOR_SIZE
241 bool "Optimize for size (Look out for broken compilers!)"
242 default y
243 depends on ARM || H8300 || EXPERIMENTAL
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800244 help
245 Enabling this option will pass "-Os" instead of "-O2" to gcc
246 resulting in a smaller kernel.
247
248 WARNING: some versions of gcc may generate incorrect code with this
249 option. If problems are observed, a gcc upgrade may be needed.
250
251 If unsure, say N.
252
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253menuconfig EMBEDDED
254 bool "Configure standard kernel features (for small systems)"
255 help
256 This option allows certain base kernel options and settings
257 to be disabled or tweaked. This is for specialized
258 environments which can tolerate a "non-standard" kernel.
259 Only use this if you really know what you are doing.
260
261config KALLSYMS
262 bool "Load all symbols for debugging/kksymoops" if EMBEDDED
263 default y
264 help
265 Say Y here to let the kernel print out symbolic crash information and
266 symbolic stack backtraces. This increases the size of the kernel
267 somewhat, as all symbols have to be loaded into the kernel image.
268
269config KALLSYMS_ALL
270 bool "Include all symbols in kallsyms"
271 depends on DEBUG_KERNEL && KALLSYMS
272 help
273 Normally kallsyms only contains the symbols of functions, for nicer
274 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200275 symbols too: say Y here to include all symbols, if you need them
276 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
278 Say N.
279
280config KALLSYMS_EXTRA_PASS
281 bool "Do an extra kallsyms pass"
282 depends on KALLSYMS
283 help
284 If kallsyms is not working correctly, the build will fail with
285 inconsistent kallsyms data. If that occurs, log a bug report and
286 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
287 Always say N here unless you find a bug in kallsyms, which must be
288 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
289 you wait for kallsyms to be fixed.
290
Matt Mackalld59745c2005-05-01 08:59:02 -0700291
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800292config HOTPLUG
293 bool "Support for hot-pluggable devices" if EMBEDDED
294 default y
295 help
296 This option is provided for the case where no hotplug or uevent
297 capabilities is wanted by the kernel. You should only consider
298 disabling this option for embedded systems that do not use modules, a
299 dynamic /dev tree, or dynamic device discovery. Just say Y.
300
Matt Mackalld59745c2005-05-01 08:59:02 -0700301config PRINTK
302 default y
303 bool "Enable support for printk" if EMBEDDED
304 help
305 This option enables normal printk support. Removing it
306 eliminates most of the message strings from the kernel image
307 and makes the kernel more or less silent. As this makes it
308 very difficult to diagnose system problems, saying N here is
309 strongly discouraged.
310
Matt Mackallc8538a72005-05-01 08:59:01 -0700311config BUG
312 bool "BUG() support" if EMBEDDED
313 default y
314 help
315 Disabling this option eliminates support for BUG and WARN, reducing
316 the size of your kernel image and potentially quietly ignoring
317 numerous fatal conditions. You should only consider disabling this
318 option for embedded systems with no facilities for reporting errors.
319 Just say Y.
320
Matt Mackall22c4e302006-01-08 01:05:24 -0800321config DOUBLEFAULT
322 depends X86
323 default y if X86
324 bool "Enable doublefault exception handler" if EMBEDDED
325 help
326 This option allows trapping of rare doublefault exceptions that
327 would otherwise cause a system to silently reboot. Disabling this
328 option saves about 4k.
329
Matt Mackall708e9a72006-01-08 01:05:25 -0800330config ELF_CORE
331 default y
332 bool "Enable ELF core dumps" if EMBEDDED
333 help
334 Enable support for generating core dumps. Disabling saves about 4k.
335
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336config BASE_FULL
337 default y
338 bool "Enable full-sized data structures for core" if EMBEDDED
339 help
340 Disabling this option reduces the size of miscellaneous core
341 kernel data structures. This saves memory on small machines,
342 but may reduce performance.
343
344config FUTEX
345 bool "Enable futex support" if EMBEDDED
346 default y
347 help
348 Disabling this option will cause the kernel to be built without
349 support for "fast userspace mutexes". The resulting kernel may not
350 run glibc-based applications correctly.
351
352config EPOLL
353 bool "Enable eventpoll support" if EMBEDDED
354 default y
355 help
356 Disabling this option will cause the kernel to be built without
357 support for epoll family of system calls.
358
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359config SHMEM
360 bool "Use full shmem filesystem" if EMBEDDED
361 default y
362 depends on MMU
363 help
364 The shmem is an internal filesystem used to manage shared memory.
365 It is backed by swap and manages resource limits. It is also exported
366 to userspace as tmpfs if TMPFS is enabled. Disabling this
367 option replaces shmem and tmpfs with the much simpler ramfs code,
368 which may be appropriate on small systems without swap.
369
370config CC_ALIGN_FUNCTIONS
371 int "Function alignment" if EMBEDDED
372 default 0
373 help
374 Align the start of functions to the next power-of-two greater than n,
375 skipping up to n bytes. For instance, 32 aligns functions
376 to the next 32-byte boundary, but 24 would align to the next
377 32-byte boundary only if this can be done by skipping 23 bytes or less.
378 Zero means use compiler's default.
379
380config CC_ALIGN_LABELS
381 int "Label alignment" if EMBEDDED
382 default 0
383 help
384 Align all branch targets to a power-of-two boundary, skipping
385 up to n bytes like ALIGN_FUNCTIONS. This option can easily
386 make code slower, because it must insert dummy operations for
387 when the branch target is reached in the usual flow of the code.
388 Zero means use compiler's default.
389
390config CC_ALIGN_LOOPS
391 int "Loop alignment" if EMBEDDED
392 default 0
393 help
394 Align loops to a power-of-two boundary, skipping up to n bytes.
395 Zero means use compiler's default.
396
397config CC_ALIGN_JUMPS
398 int "Jump alignment" if EMBEDDED
399 default 0
400 help
401 Align branch targets to a power-of-two boundary, for branch
402 targets where the targets can only be reached by jumping,
403 skipping up to n bytes like ALIGN_FUNCTIONS. In this case,
404 no dummy operations need be executed.
405 Zero means use compiler's default.
406
Matt Mackall10cef602006-01-08 01:01:45 -0800407config SLAB
408 default y
409 bool "Use full SLAB allocator" if EMBEDDED
410 help
411 Disabling this replaces the advanced SLAB allocator and
412 kmalloc support with the drastically simpler SLOB allocator.
413 SLOB is more space efficient but does not scale well and is
414 more susceptible to fragmentation.
415
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416endmenu # General setup
417
418config TINY_SHMEM
419 default !SHMEM
420 bool
421
422config BASE_SMALL
423 int
424 default 0 if BASE_FULL
425 default 1 if !BASE_FULL
426
Matt Mackall10cef602006-01-08 01:01:45 -0800427config SLOB
428 default !SLAB
429 bool
430
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431menu "Loadable module support"
432
433config MODULES
434 bool "Enable loadable module support"
435 help
436 Kernel modules are small pieces of compiled code which can
437 be inserted in the running kernel, rather than being
438 permanently built into the kernel. You use the "modprobe"
439 tool to add (and sometimes remove) them. If you say Y here,
440 many parts of the kernel can be built as modules (by
441 answering M instead of Y where indicated): this is most
442 useful for infrequently used options which are not required
443 for booting. For more information, see the man pages for
444 modprobe, lsmod, modinfo, insmod and rmmod.
445
446 If you say Y here, you will need to run "make
447 modules_install" to put the modules under /lib/modules/
448 where modprobe can find them (you may need to be root to do
449 this).
450
451 If unsure, say Y.
452
453config MODULE_UNLOAD
454 bool "Module unloading"
455 depends on MODULES
456 help
457 Without this option you will not be able to unload any
458 modules (note that some modules may not be unloadable
459 anyway), which makes your kernel slightly smaller and
460 simpler. If unsure, say Y.
461
462config MODULE_FORCE_UNLOAD
463 bool "Forced module unloading"
464 depends on MODULE_UNLOAD && EXPERIMENTAL
465 help
466 This option allows you to force a module to unload, even if the
467 kernel believes it is unsafe: the kernel will remove the module
468 without waiting for anyone to stop using it (using the -f option to
469 rmmod). This is mainly for kernel developers and desperate users.
470 If unsure, say N.
471
472config OBSOLETE_MODPARM
473 bool
474 default y
475 depends on MODULES
476 help
477 You need this option to use module parameters on modules which
478 have not been converted to the new module parameter system yet.
479 If unsure, say Y.
480
481config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +0100482 bool "Module versioning support"
483 depends on MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700484 help
485 Usually, you have to use modules compiled with your kernel.
486 Saying Y here makes it sometimes possible to use modules
487 compiled for different kernels, by adding enough information
488 to the modules to (hopefully) spot any changes which would
489 make them incompatible with the kernel you are running. If
490 unsure, say N.
491
492config MODULE_SRCVERSION_ALL
493 bool "Source checksum for all modules"
494 depends on MODULES
495 help
496 Modules which contain a MODULE_VERSION get an extra "srcversion"
497 field inserted into their modinfo section, which contains a
498 sum of the source files which made it. This helps maintainers
499 see exactly which source was used to build a module (since
500 others sometimes change the module source without updating
501 the version). With this option, such a "srcversion" field
502 will be created for all modules. If unsure, say N.
503
504config KMOD
505 bool "Automatic kernel module loading"
506 depends on MODULES
507 help
508 Normally when you have selected some parts of the kernel to
509 be created as kernel modules, you must load them (using the
510 "modprobe" command) before you can use them. If you say Y
511 here, some parts of the kernel will be able to load modules
512 automatically: when a part of the kernel needs a module, it
513 runs modprobe with the appropriate arguments, thereby
514 loading the module if it is available. If unsure, say Y.
515
516config STOP_MACHINE
517 bool
518 default y
519 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
520 help
521 Need stop_machine() primitive.
522endmenu
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100523
524menu "Block layer"
525source "block/Kconfig"
526endmenu