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Roman Zippel80daa562008-01-14 04:51:16 +01001config ARCH
2 string
3 option env="ARCH"
4
5config KERNELVERSION
6 string
7 option env="KERNELVERSION"
8
Roman Zippelface4372006-06-08 22:12:45 -07009config DEFCONFIG_LIST
10 string
Paolo 'Blaisorblade' Giarrussob2670eac2006-10-19 23:28:23 -070011 depends on !UML
Roman Zippelface4372006-06-08 22:12:45 -070012 option defconfig_list
13 default "/lib/modules/$UNAME_RELEASE/.config"
14 default "/etc/kernel-config"
15 default "/boot/config-$UNAME_RELEASE"
Sam Ravnborg73531902008-05-25 23:03:18 +020016 default "$ARCH_DEFCONFIG"
Roman Zippelface4372006-06-08 22:12:45 -070017 default "arch/$ARCH/defconfig"
18
Al Boldiff0cfc62007-07-31 00:39:23 -070019menu "General setup"
Linus Torvalds1da177e2005-04-16 15:20:36 -070020
21config EXPERIMENTAL
22 bool "Prompt for development and/or incomplete code/drivers"
23 ---help---
24 Some of the various things that Linux supports (such as network
25 drivers, file systems, network protocols, etc.) can be in a state
26 of development where the functionality, stability, or the level of
27 testing is not yet high enough for general use. This is usually
28 known as the "alpha-test" phase among developers. If a feature is
29 currently in alpha-test, then the developers usually discourage
30 uninformed widespread use of this feature by the general public to
31 avoid "Why doesn't this work?" type mail messages. However, active
32 testing and use of these systems is welcomed. Just be aware that it
33 may not meet the normal level of reliability or it may fail to work
34 in some special cases. Detailed bug reports from people familiar
35 with the kernel internals are usually welcomed by the developers
36 (before submitting bug reports, please read the documents
37 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
38 <file:Documentation/BUG-HUNTING>, and
39 <file:Documentation/oops-tracing.txt> in the kernel source).
40
41 This option will also make obsoleted drivers available. These are
42 drivers that have been replaced by something else, and/or are
43 scheduled to be removed in a future kernel release.
44
45 Unless you intend to help test and develop a feature or driver that
46 falls into this category, or you have a situation that requires
47 using these features, you should probably say N here, which will
48 cause the configurator to present you with fewer choices. If
49 you say Y here, you will be offered the choice of using features or
50 drivers that are currently considered to be in the alpha-test phase.
51
Linus Torvalds1da177e2005-04-16 15:20:36 -070052config BROKEN
53 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -070054
55config BROKEN_ON_SMP
56 bool
57 depends on BROKEN || !SMP
58 default y
59
60config LOCK_KERNEL
61 bool
62 depends on SMP || PREEMPT
63 default y
64
65config INIT_ENV_ARG_LIMIT
66 int
Adrian Bunkdd673bc2006-06-30 01:55:51 -070067 default 32 if !UML
68 default 128 if UML
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 help
Randy Dunlap34ad92c22005-10-30 15:01:46 -080070 Maximum of each of the number of arguments and environment
71 variables passed to init from the kernel command line.
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74config LOCALVERSION
75 string "Local version - append to kernel release"
76 help
77 Append an extra string to the end of your kernel version.
78 This will show up when you type uname, for example.
79 The string you set here will be appended after the contents of
80 any files with a filename matching localversion* in your
81 object and source tree, in that order. Your total string can
82 be a maximum of 64 characters.
83
Ryan Andersonaaebf432005-07-31 04:57:49 -040084config LOCALVERSION_AUTO
85 bool "Automatically append version information to the version string"
86 default y
87 help
88 This will try to automatically determine if the current tree is a
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020089 release tree by looking for git tags that belong to the current
90 top of tree revision.
Ryan Andersonaaebf432005-07-31 04:57:49 -040091
92 A string of the format -gxxxxxxxx will be added to the localversion
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020093 if a git-based tree is found. The string generated by this will be
Ryan Andersonaaebf432005-07-31 04:57:49 -040094 appended after any matching localversion* files, and after the value
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020095 set in CONFIG_LOCALVERSION.
Ryan Andersonaaebf432005-07-31 04:57:49 -040096
Robert P. J. Day6e5a5422007-05-01 23:08:11 +020097 (The actual string used here is the first eight characters produced
98 by running the command:
99
100 $ git rev-parse --verify HEAD
101
102 which is done within the script "scripts/setlocalversion".)
Ryan Andersonaaebf432005-07-31 04:57:49 -0400103
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104config SWAP
105 bool "Support for paging of anonymous memory (swap)"
David Howells93614012006-09-30 20:45:40 +0200106 depends on MMU && BLOCK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 default y
108 help
109 This option allows you to choose whether you want to have support
Jesper Juhl92c35042006-01-15 02:40:08 +0100110 for so called swap devices or swap files in your kernel that are
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111 used to provide more virtual memory than the actual RAM present
112 in your computer. If unsure say Y.
113
114config SYSVIPC
115 bool "System V IPC"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 ---help---
117 Inter Process Communication is a suite of library functions and
118 system calls which let processes (running programs) synchronize and
119 exchange information. It is generally considered to be a good thing,
120 and some programs won't run unless you say Y here. In particular, if
121 you want to run the DOS emulator dosemu under Linux (read the
122 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
123 you'll need to say Y here.
124
125 You can find documentation about IPC with "info ipc" and also in
126 section 6.4 of the Linux Programmer's Guide, available from
127 <http://www.tldp.org/guides.html>.
128
Eric W. Biedermana5494dc2007-02-14 00:34:06 -0800129config SYSVIPC_SYSCTL
130 bool
131 depends on SYSVIPC
132 depends on SYSCTL
133 default y
134
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135config POSIX_MQUEUE
136 bool "POSIX Message Queues"
137 depends on NET && EXPERIMENTAL
138 ---help---
139 POSIX variant of message queues is a part of IPC. In POSIX message
140 queues every message has a priority which decides about succession
141 of receiving it by a process. If you want to compile and run
142 programs written e.g. for Solaris with use of its POSIX message
Robert P. J. Dayb0e37652007-05-09 07:25:13 +0200143 queues (functions mq_*) say Y here.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144
145 POSIX message queues are visible as a filesystem called 'mqueue'
146 and can be mounted somewhere if you want to do filesystem
147 operations on message queues.
148
149 If unsure, say Y.
150
151config BSD_PROCESS_ACCT
152 bool "BSD Process Accounting"
153 help
154 If you say Y here, a user level program will be able to instruct the
155 kernel (via a special system call) to write process accounting
156 information to a file: whenever a process exits, information about
157 that process will be appended to the file by the kernel. The
158 information includes things such as creation time, owning user,
159 command name, memory usage, controlling terminal etc. (the complete
160 list is in the struct acct in <file:include/linux/acct.h>). It is
161 up to the user level program to do useful things with this
162 information. This is generally a good idea, so say Y.
163
164config BSD_PROCESS_ACCT_V3
165 bool "BSD Process Accounting version 3 file format"
166 depends on BSD_PROCESS_ACCT
167 default n
168 help
169 If you say Y here, the process accounting information is written
170 in a new file format that also logs the process IDs of each
171 process and it's parent. Note that this file format is incompatible
172 with previous v0/v1/v2 file formats, so you will need updated tools
173 for processing it. A preliminary version of these tools is available
S.Çağlar Onur37a4c942008-06-18 11:45:13 +0300174 at <http://www.gnu.org/software/acct/>.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700175
Shailabh Nagarc7572492006-07-14 00:24:40 -0700176config TASKSTATS
177 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
178 depends on NET
179 default n
180 help
181 Export selected statistics for tasks/processes through the
182 generic netlink interface. Unlike BSD process accounting, the
183 statistics are available during the lifetime of tasks/processes as
184 responses to commands. Like BSD accounting, they are sent to user
185 space on task exit.
186
187 Say N if unsure.
188
Shailabh Nagarca74e922006-07-14 00:24:36 -0700189config TASK_DELAY_ACCT
190 bool "Enable per-task delay accounting (EXPERIMENTAL)"
Shailabh Nagar6f449932006-07-14 00:24:41 -0700191 depends on TASKSTATS
Shailabh Nagarca74e922006-07-14 00:24:36 -0700192 help
193 Collect information on time spent by a task waiting for system
194 resources like cpu, synchronous block I/O completion and swapping
195 in pages. Such statistics can help in setting a task's priorities
196 relative to other tasks for cpu, io, rss limits etc.
197
198 Say N if unsure.
199
Alexey Dobriyan18f705f2007-02-10 01:46:44 -0800200config TASK_XACCT
201 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
202 depends on TASKSTATS
203 help
204 Collect extended task accounting data and send the data
205 to userland for processing over the taskstats interface.
206
207 Say N if unsure.
208
209config TASK_IO_ACCOUNTING
210 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
211 depends on TASK_XACCT
212 help
213 Collect information on the number of bytes of storage I/O which this
214 task has caused.
215
216 Say N if unsure.
217
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218config AUDIT
219 bool "Auditing support"
Chris Wright804a6a492005-05-11 10:52:45 +0100220 depends on NET
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 help
222 Enable auditing infrastructure that can be used with another
223 kernel subsystem, such as SELinux (which requires this for
224 logging of avc messages output). Does not do system-call
225 auditing without CONFIG_AUDITSYSCALL.
226
227config AUDITSYSCALL
228 bool "Enable system-call auditing support"
Yuichi Nakamura1322b9d2007-11-10 19:21:34 +0900229 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64|| SUPERH)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 default y if SECURITY_SELINUX
231 help
232 Enable low-overhead system-call auditing infrastructure that
233 can be used independently or with another kernel subsystem,
Amy Griffisf368c07d2006-04-07 16:55:56 -0400234 such as SELinux. To use audit's filesystem watch feature, please
235 ensure that INOTIFY is configured.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236
Al Viro74c3cbe2007-07-22 08:04:18 -0400237config AUDIT_TREE
238 def_bool y
239 depends on AUDITSYSCALL && INOTIFY
240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241config IKCONFIG
Ross Birof2443ab2006-09-30 23:27:25 -0700242 tristate "Kernel .config support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 ---help---
244 This option enables the complete Linux kernel ".config" file
245 contents to be saved in the kernel. It provides documentation
246 of which kernel options are used in a running kernel or in an
247 on-disk kernel. This information can be extracted from the kernel
248 image file with the script scripts/extract-ikconfig and used as
249 input to rebuild the current kernel or to build another kernel.
250 It can also be extracted from a running kernel by reading
251 /proc/config.gz if enabled (below).
252
253config IKCONFIG_PROC
254 bool "Enable access to .config through /proc/config.gz"
255 depends on IKCONFIG && PROC_FS
256 ---help---
257 This option enables access to the kernel configuration file
258 through /proc/config.gz.
259
Alistair John Strachan794543a2007-05-08 00:31:15 -0700260config LOG_BUF_SHIFT
261 int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
262 range 12 21
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700263 default 17
Alistair John Strachan794543a2007-05-08 00:31:15 -0700264 help
265 Select kernel log buffer size as a power of 2.
Adrian Bunkf17a32e2008-04-29 00:58:58 -0700266 Examples:
267 17 => 128 KB
268 16 => 64 KB
269 15 => 32 KB
270 14 => 16 KB
Alistair John Strachan794543a2007-05-08 00:31:15 -0700271 13 => 8 KB
272 12 => 4 KB
273
Paul Menageddbcc7e2007-10-18 23:39:30 -0700274config CGROUPS
275 bool "Control Group support"
276 help
277 This option will let you use process cgroup subsystems
278 such as Cpusets
279
280 Say N if unsure.
281
Paul Menage006cb992007-10-18 23:39:43 -0700282config CGROUP_DEBUG
283 bool "Example debug cgroup subsystem"
284 depends on CGROUPS
Paul Menage418d7d82008-04-29 01:00:05 -0700285 default n
Paul Menage006cb992007-10-18 23:39:43 -0700286 help
287 This option enables a simple cgroup subsystem that
288 exports useful debugging information about the cgroups
289 framework
290
291 Say N if unsure
292
Serge E. Hallyn858d72e2007-10-18 23:39:45 -0700293config CGROUP_NS
294 bool "Namespace cgroup subsystem"
295 depends on CGROUPS
296 help
297 Provides a simple namespace cgroup subsystem to
298 provide hierarchical naming of sets of namespaces,
299 for instance virtual servers and checkpoint/restart
300 jobs.
301
Matt Helsleydc52ddc2008-10-18 20:27:21 -0700302config CGROUP_FREEZER
303 bool "control group freezer subsystem"
304 depends on CGROUPS
305 help
306 Provides a way to freeze and unfreeze all tasks in a
307 cgroup.
308
Serge E. Hallyn08ce5f12008-04-29 01:00:10 -0700309config CGROUP_DEVICE
310 bool "Device controller for cgroups"
311 depends on CGROUPS && EXPERIMENTAL
312 help
313 Provides a cgroup implementing whitelists for devices which
314 a process in the cgroup can mknod or open.
315
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316config CPUSETS
317 bool "Cpuset support"
Paul Menage8793d852007-10-18 23:39:39 -0700318 depends on SMP && CGROUPS
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319 help
Randy Dunlapd9fd8a62005-07-27 11:45:11 -0700320 This option will let you create and manage CPUSETs which
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 allow dynamically partitioning a system into sets of CPUs and
322 Memory Nodes and assigning tasks to run only within those sets.
323 This is primarily useful on large SMP or NUMA systems.
324
325 Say N if unsure.
326
Ingo Molnara5574cf2008-05-05 23:19:50 +0200327#
328# Architectures with an unreliable sched_clock() should select this:
329#
330config HAVE_UNSTABLE_SCHED_CLOCK
331 bool
332
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100333config GROUP_SCHED
334 bool "Group CPU scheduler"
Parag Warudkaraac6abc2008-05-03 20:42:34 -0400335 depends on EXPERIMENTAL
336 default n
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200337 help
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200338 This feature lets CPU scheduler recognize task groups and control CPU
Srivatsa Vaddagiri9b5b7752007-10-15 17:00:09 +0200339 bandwidth allocation to such task groups.
Srivatsa Vaddagiri29f59db2007-10-15 17:00:07 +0200340
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100341config FAIR_GROUP_SCHED
342 bool "Group scheduling for SCHED_OTHER"
343 depends on GROUP_SCHED
Parag Warudkaraac6abc2008-05-03 20:42:34 -0400344 default GROUP_SCHED
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200345
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100346config RT_GROUP_SCHED
347 bool "Group scheduling for SCHED_RR/FIFO"
348 depends on EXPERIMENTAL
349 depends on GROUP_SCHED
350 default n
Viktor Radnaib9b158f2008-04-19 19:45:01 +0200351 help
352 This feature lets you explicitly allocate real CPU bandwidth
353 to users or control groups (depending on the "Basis for grouping tasks"
354 setting below. If enabled, it will also make it impossible to
355 schedule realtime tasks for non-root users until you allocate
356 realtime bandwidth for them.
357 See Documentation/sched-rt-group.txt for more information.
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100358
359choice
360 depends on GROUP_SCHED
361 prompt "Basis for grouping tasks"
362 default USER_SCHED
363
364config USER_SCHED
Srivatsa Vaddagirifb615582007-10-15 17:00:12 +0200365 bool "user id"
366 help
367 This option will choose userid as the basis for grouping
368 tasks, thus providing equal CPU bandwidth to each user.
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200369
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100370config CGROUP_SCHED
Srivatsa Vaddagiri68318b82007-10-18 23:41:03 -0700371 bool "Control groups"
372 depends on CGROUPS
373 help
374 This option allows you to create arbitrary task groups
375 using the "cgroup" pseudo filesystem and control
376 the cpu bandwidth allocated to each such task group.
377 Refer to Documentation/cgroups.txt for more information
378 on "cgroup" pseudo filesystem.
379
Srivatsa Vaddagiri24e377a2007-10-15 17:00:09 +0200380endchoice
381
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100382config CGROUP_CPUACCT
383 bool "Simple CPU accounting cgroup subsystem"
384 depends on CGROUPS
385 help
386 Provides a simple Resource Controller for monitoring the
387 total CPU consumed by the tasks in a cgroup
388
Pavel Emelianove552b662008-02-07 00:13:49 -0800389config RESOURCE_COUNTERS
390 bool "Resource counters"
391 help
392 This option enables controller independent resource accounting
393 infrastructure that works with cgroups
394 depends on CGROUPS
395
Balbir Singhcf475ad2008-04-29 01:00:16 -0700396config MM_OWNER
397 bool
398
Balbir Singh00f0b822008-03-04 14:28:39 -0800399config CGROUP_MEM_RES_CTLR
400 bool "Memory Resource Controller for Control Groups"
401 depends on CGROUPS && RESOURCE_COUNTERS
Balbir Singhcf475ad2008-04-29 01:00:16 -0700402 select MM_OWNER
Balbir Singh00f0b822008-03-04 14:28:39 -0800403 help
404 Provides a memory resource controller that manages both page cache and
405 RSS memory.
406
407 Note that setting this option increases fixed memory overhead
408 associated with each page of memory in the system by 4/8 bytes
409 and also increases cache misses because struct page on many 64bit
410 systems will not fit into a single cache line anymore.
411
412 Only enable when you're ok with these trade offs and really
413 sure you need the memory resource controller.
414
Balbir Singhcf475ad2008-04-29 01:00:16 -0700415 This config option also selects MM_OWNER config option, which
416 could in turn add some fork/exit overhead.
417
Kay Sievers88a22c92006-09-14 11:23:28 +0200418config SYSFS_DEPRECATED
Ingo Molnard47846c2008-03-04 14:54:47 +0100419 bool
420
421config SYSFS_DEPRECATED_V2
Kay Sievers88a22c92006-09-14 11:23:28 +0200422 bool "Create deprecated sysfs files"
Randy Dunlap9148fe82007-12-31 10:05:34 -0800423 depends on SYSFS
Kay Sievers88a22c92006-09-14 11:23:28 +0200424 default y
Ingo Molnard47846c2008-03-04 14:54:47 +0100425 select SYSFS_DEPRECATED
Kay Sievers88a22c92006-09-14 11:23:28 +0200426 help
427 This option creates deprecated symlinks such as the
428 "device"-link, the <subsystem>:<name>-link, and the
429 "bus"-link. It may also add deprecated key in the
430 uevent environment.
431 None of these features or values should be used today, as
432 they export driver core implementation details to userspace
433 or export properties which can't be kept stable across kernel
434 releases.
435
436 If enabled, this option will also move any device structures
David Sterba3dde6ad2007-05-09 07:12:20 +0200437 that belong to a class, back into the /sys/class hierarchy, in
Greg Kroah-Hartman024440d2008-03-03 14:47:13 -0800438 order to support older versions of udev and some userspace
439 programs.
Kay Sievers88a22c92006-09-14 11:23:28 +0200440
Greg Kroah-Hartman024440d2008-03-03 14:47:13 -0800441 If you are using a distro with the most recent userspace
442 packages, it should be safe to say N here.
Kay Sievers88a22c92006-09-14 11:23:28 +0200443
Paul Menage8793d852007-10-18 23:39:39 -0700444config PROC_PID_CPUSET
445 bool "Include legacy /proc/<pid>/cpuset file"
446 depends on CPUSETS
447 default y
448
Jens Axboeb86ff9812006-03-23 19:56:55 +0100449config RELAY
450 bool "Kernel->user space relay support (formerly relayfs)"
451 help
452 This option enables support for relay interface support in
453 certain file systems (such as debugfs).
454 It is designed to provide an efficient mechanism for tools and
455 facilities to relay large amounts of data from kernel space to
456 user space.
457
458 If unsure, say N.
459
Pavel Emelyanovc5289a62008-02-08 04:18:19 -0800460config NAMESPACES
461 bool "Namespaces support" if EMBEDDED
462 default !EMBEDDED
463 help
464 Provides the way to make tasks work with different objects using
465 the same id. For example same IPC id may refer to different objects
466 or same user id or pid may refer to different tasks when used in
467 different namespaces.
468
Pavel Emelyanov58bfdd6d2008-02-08 04:18:21 -0800469config UTS_NS
470 bool "UTS namespace"
471 depends on NAMESPACES
472 help
473 In this namespace tasks see different info provided with the
474 uname() system call
475
Pavel Emelyanovae5e1b22008-02-08 04:18:22 -0800476config IPC_NS
477 bool "IPC namespace"
478 depends on NAMESPACES && SYSVIPC
479 help
480 In this namespace tasks work with IPC ids which correspond to
481 different IPC objects in different namespaces
482
Pavel Emelyanovaee16ce2008-02-08 04:18:23 -0800483config USER_NS
484 bool "User namespace (EXPERIMENTAL)"
485 depends on NAMESPACES && EXPERIMENTAL
486 help
487 This allows containers, i.e. vservers, to use user namespaces
488 to provide different user info for different servers.
489 If unsure, say N.
490
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800491config PID_NS
492 bool "PID Namespaces (EXPERIMENTAL)"
493 default n
494 depends on NAMESPACES && EXPERIMENTAL
495 help
Heikki Orsila12d2b8f2008-07-06 15:48:02 +0300496 Support process id namespaces. This allows having multiple
Pavel Emelyanov74bd59b2008-02-08 04:18:24 -0800497 process with the same pid as long as they are in different
498 pid namespaces. This is a building block of containers.
499
500 Unless you want to work with an experimental feature
501 say N here.
502
Dimitri Gorokhovikf9916332007-03-06 01:42:17 -0800503config BLK_DEV_INITRD
504 bool "Initial RAM filesystem and RAM disk (initramfs/initrd) support"
505 depends on BROKEN || !FRV
506 help
507 The initial RAM filesystem is a ramfs which is loaded by the
508 boot loader (loadlin or lilo) and that is mounted as root
509 before the normal boot procedure. It is typically used to
510 load modules needed to mount the "real" root file system,
511 etc. See <file:Documentation/initrd.txt> for details.
512
513 If RAM disk support (BLK_DEV_RAM) is also included, this
514 also enables initial RAM disk (initrd) support and adds
515 15 Kbytes (more on some other architectures) to the kernel size.
516
517 If unsure say Y.
518
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800519if BLK_DEV_INITRD
520
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200521source "usr/Kconfig"
522
Jean-Paul Samanc33df4e2007-02-10 01:44:43 -0800523endif
524
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800525config CC_OPTIMIZE_FOR_SIZE
Ingo Molnar96fffeb2008-04-28 01:39:43 +0200526 bool "Optimize for size"
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800527 default y
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800528 help
529 Enabling this option will pass "-Os" instead of "-O2" to gcc
530 resulting in a smaller kernel.
531
jkacur775a7222008-07-16 00:31:16 +0200532 If unsure, say Y.
Linus Torvaldsc45b4f12005-12-14 18:52:21 -0800533
Randy Dunlap08470622006-09-30 23:28:13 -0700534config SYSCTL
535 bool
536
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537menuconfig EMBEDDED
538 bool "Configure standard kernel features (for small systems)"
539 help
540 This option allows certain base kernel options and settings
541 to be disabled or tweaked. This is for specialized
542 environments which can tolerate a "non-standard" kernel.
543 Only use this if you really know what you are doing.
544
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700545config UID16
546 bool "Enable 16-bit UID system calls" if EMBEDDED
David S. Miller09337f52008-04-26 03:17:12 -0700547 depends on ARM || BLACKFIN || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && COMPAT) || UML || (X86_64 && IA32_EMULATION)
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700548 default y
549 help
550 This enables the legacy 16-bit UID syscall wrappers.
551
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700552config SYSCTL_SYSCALL
Randy Dunlap08470622006-09-30 23:28:13 -0700553 bool "Sysctl syscall support" if EMBEDDED
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800554 default y
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700555 select SYSCTL
556 ---help---
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800557 sys_sysctl uses binary paths that have been found challenging
558 to properly maintain and use. The interface in /proc/sys
559 using paths with ascii names is now the primary path to this
560 information.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700561
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800562 Almost nothing using the binary sysctl interface so if you are
563 trying to save some space it is probably safe to disable this,
564 making your kernel marginally smaller.
Eric W. Biedermanb89a8172006-09-27 01:51:04 -0700565
Eric W. Biederman13bb7e32006-11-08 17:44:51 -0800566 If unsure say Y here.
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700567
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568config KALLSYMS
Jesper Juhl979c6a12006-12-12 19:25:11 +0100569 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570 default y
571 help
572 Say Y here to let the kernel print out symbolic crash information and
573 symbolic stack backtraces. This increases the size of the kernel
574 somewhat, as all symbols have to be loaded into the kernel image.
575
576config KALLSYMS_ALL
577 bool "Include all symbols in kallsyms"
578 depends on DEBUG_KERNEL && KALLSYMS
579 help
580 Normally kallsyms only contains the symbols of functions, for nicer
581 OOPS messages. Some debuggers can use kallsyms for other
Jesper Juhlf9f97bc2005-07-20 05:43:05 +0200582 symbols too: say Y here to include all symbols, if you need them
583 and you don't care about adding 300k to the size of your kernel.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584
585 Say N.
586
587config KALLSYMS_EXTRA_PASS
588 bool "Do an extra kallsyms pass"
589 depends on KALLSYMS
590 help
591 If kallsyms is not working correctly, the build will fail with
592 inconsistent kallsyms data. If that occurs, log a bug report and
593 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
594 Always say N here unless you find a bug in kallsyms, which must be
595 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
596 you wait for kallsyms to be fixed.
597
Matt Mackalld59745c2005-05-01 08:59:02 -0700598
Greg Kroah-Hartman712f47c2005-11-16 11:27:07 -0800599config HOTPLUG
600 bool "Support for hot-pluggable devices" if EMBEDDED
601 default y
602 help
603 This option is provided for the case where no hotplug or uevent
604 capabilities is wanted by the kernel. You should only consider
605 disabling this option for embedded systems that do not use modules, a
606 dynamic /dev tree, or dynamic device discovery. Just say Y.
607
Matt Mackalld59745c2005-05-01 08:59:02 -0700608config PRINTK
609 default y
610 bool "Enable support for printk" if EMBEDDED
611 help
612 This option enables normal printk support. Removing it
613 eliminates most of the message strings from the kernel image
614 and makes the kernel more or less silent. As this makes it
615 very difficult to diagnose system problems, saying N here is
616 strongly discouraged.
617
Matt Mackallc8538a72005-05-01 08:59:01 -0700618config BUG
619 bool "BUG() support" if EMBEDDED
620 default y
621 help
622 Disabling this option eliminates support for BUG and WARN, reducing
623 the size of your kernel image and potentially quietly ignoring
624 numerous fatal conditions. You should only consider disabling this
625 option for embedded systems with no facilities for reporting errors.
626 Just say Y.
627
Matt Mackall708e9a72006-01-08 01:05:25 -0800628config ELF_CORE
629 default y
630 bool "Enable ELF core dumps" if EMBEDDED
631 help
632 Enable support for generating core dumps. Disabling saves about 4k.
633
Stas Sergeeve5e1d3c2008-05-07 12:39:56 +0200634config PCSPKR_PLATFORM
635 bool "Enable PC-Speaker support" if EMBEDDED
636 depends on ALPHA || X86 || MIPS || PPC_PREP || PPC_CHRP || PPC_PSERIES
637 default y
638 help
639 This option allows to disable the internal PC-Speaker
640 support, saving some memory.
641
Ingo Molnar32a93232008-02-06 22:39:44 +0100642config COMPAT_BRK
643 bool "Disable heap randomization"
644 default y
645 help
646 Randomizing heap placement makes heap exploits harder, but it
647 also breaks ancient binaries (including anything libc5 based).
648 This option changes the bootup default to heap randomization
649 disabled, and can be overriden runtime by setting
650 /proc/sys/kernel/randomize_va_space to 2.
651
Ingo Molnar166124f2008-02-09 23:24:09 +0100652 On non-ancient distros (post-2000 ones) N is usually a safe choice.
Ingo Molnar32a93232008-02-06 22:39:44 +0100653
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654config BASE_FULL
655 default y
656 bool "Enable full-sized data structures for core" if EMBEDDED
657 help
658 Disabling this option reduces the size of miscellaneous core
659 kernel data structures. This saves memory on small machines,
660 but may reduce performance.
661
662config FUTEX
663 bool "Enable futex support" if EMBEDDED
664 default y
Ingo Molnar23f78d4a2006-06-27 02:54:53 -0700665 select RT_MUTEXES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 help
667 Disabling this option will cause the kernel to be built without
668 support for "fast userspace mutexes". The resulting kernel may not
669 run glibc-based applications correctly.
670
Davide Libenzi5dc8bf82007-05-10 22:23:11 -0700671config ANON_INODES
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700672 bool
Davide Libenzi5dc8bf82007-05-10 22:23:11 -0700673
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674config EPOLL
675 bool "Enable eventpoll support" if EMBEDDED
676 default y
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700677 select ANON_INODES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678 help
679 Disabling this option will cause the kernel to be built without
680 support for epoll family of system calls.
681
Davide Libenzifba2afa2007-05-10 22:23:13 -0700682config SIGNALFD
683 bool "Enable signalfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700684 select ANON_INODES
Davide Libenzifba2afa2007-05-10 22:23:13 -0700685 default y
686 help
687 Enable the signalfd() system call that allows to receive signals
688 on a file descriptor.
689
690 If unsure, say Y.
691
Davide Libenzib215e282007-05-10 22:23:16 -0700692config TIMERFD
693 bool "Enable timerfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700694 select ANON_INODES
Davide Libenzib215e282007-05-10 22:23:16 -0700695 default y
696 help
697 Enable the timerfd() system call that allows to receive timer
698 events on a file descriptor.
699
700 If unsure, say Y.
701
Davide Libenzie1ad7462007-05-10 22:23:19 -0700702config EVENTFD
703 bool "Enable eventfd() system call" if EMBEDDED
Adrian Bunk448e3ce2007-07-31 00:39:10 -0700704 select ANON_INODES
Davide Libenzie1ad7462007-05-10 22:23:19 -0700705 default y
706 help
707 Enable the eventfd() system call that allows to receive both
708 kernel notification (ie. KAIO) or userspace notifications.
709
710 If unsure, say Y.
711
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712config SHMEM
713 bool "Use full shmem filesystem" if EMBEDDED
714 default y
715 depends on MMU
716 help
717 The shmem is an internal filesystem used to manage shared memory.
718 It is backed by swap and manages resource limits. It is also exported
719 to userspace as tmpfs if TMPFS is enabled. Disabling this
720 option replaces shmem and tmpfs with the much simpler ramfs code,
721 which may be appropriate on small systems without swap.
722
Thomas Petazzoniebf3f092008-10-15 22:05:12 -0700723config AIO
724 bool "Enable AIO support" if EMBEDDED
725 default y
726 help
727 This option enables POSIX asynchronous I/O which may by used
728 by some high performance threaded applications. Disabling
729 this option saves about 7k.
730
Christoph Lameterf8891e52006-06-30 01:55:45 -0700731config VM_EVENT_COUNTERS
732 default y
733 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
734 help
Paul Jackson2aea4fb2006-12-22 01:06:10 -0800735 VM event counters are needed for event counts to be shown.
736 This option allows the disabling of the VM event counters
737 on EMBEDDED systems. /proc/vmstat will only show page counts
738 if VM event counters are disabled.
Christoph Lameterf8891e52006-06-30 01:55:45 -0700739
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200740config PCI_QUIRKS
741 default y
Geert Uytterhoeven61cfc7e2008-10-22 08:53:25 +0200742 bool "Enable PCI quirk workarounds" if EMBEDDED
743 depends on PCI
Thomas Petazzoni3d137312008-08-19 10:28:24 +0200744 help
745 This enables workarounds for various PCI chipset
746 bugs/quirks. Disable this only if your target machine is
747 unaffected by PCI quirks.
748
Christoph Lameter41ecc552007-05-09 02:32:44 -0700749config SLUB_DEBUG
750 default y
751 bool "Enable SLUB debugging support" if EMBEDDED
Christoph Lameterf6acb632008-04-29 16:16:06 -0700752 depends on SLUB && SYSFS
Christoph Lameter41ecc552007-05-09 02:32:44 -0700753 help
754 SLUB has extensive debug support features. Disabling these can
755 result in significant savings in code size. This also disables
756 SLUB sysfs support. /sys/slab will not exist and there will be
757 no support for cache validation etc.
758
Christoph Lameter81819f02007-05-06 14:49:36 -0700759choice
760 prompt "Choose SLAB allocator"
Christoph Lametera0acd822007-07-17 04:03:32 -0700761 default SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -0700762 help
763 This option allows to select a slab allocator.
764
765config SLAB
766 bool "SLAB"
767 help
768 The regular slab allocator that is established and known to work
Christoph Lameter34013882007-05-09 02:32:47 -0700769 well in all environments. It organizes cache hot objects in
Christoph Lameter81819f02007-05-06 14:49:36 -0700770 per cpu and per node queues. SLAB is the default choice for
Christoph Lameter34013882007-05-09 02:32:47 -0700771 a slab allocator.
Christoph Lameter81819f02007-05-06 14:49:36 -0700772
773config SLUB
Christoph Lameter81819f02007-05-06 14:49:36 -0700774 bool "SLUB (Unqueued Allocator)"
775 help
776 SLUB is a slab allocator that minimizes cache line usage
777 instead of managing queues of cached objects (SLAB approach).
778 Per cpu caching is realized using slabs of objects instead
779 of queues of objects. SLUB can use memory efficiently
Christoph Lameter34013882007-05-09 02:32:47 -0700780 and has enhanced diagnostics.
Christoph Lameter81819f02007-05-06 14:49:36 -0700781
782config SLOB
Paul Mundt84a01c22007-07-15 23:38:24 -0700783 depends on EMBEDDED
Christoph Lameter81819f02007-05-06 14:49:36 -0700784 bool "SLOB (Simple Allocator)"
785 help
Matt Mackall37291452008-02-04 22:29:38 -0800786 SLOB replaces the stock allocator with a drastically simpler
787 allocator. SLOB is generally more space efficient but
788 does not perform as well on large systems.
Christoph Lameter81819f02007-05-06 14:49:36 -0700789
790endchoice
791
Mathieu Desnoyers125e5642008-02-02 15:10:36 -0500792config PROFILING
793 bool "Profiling support (EXPERIMENTAL)"
794 help
795 Say Y here to enable the extended profiling support mechanisms used
796 by profilers such as OProfile.
797
Ingo Molnar5f87f112008-07-23 14:15:22 +0200798#
799# Place an empty function call at each tracepoint site. Can be
800# dynamically changed for a probe function.
801#
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -0400802config TRACEPOINTS
Ingo Molnar5f87f112008-07-23 14:15:22 +0200803 bool
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -0400804
Mathieu Desnoyers125e5642008-02-02 15:10:36 -0500805config MARKERS
806 bool "Activate markers"
807 help
808 Place an empty function call at each marker site. Can be
809 dynamically changed for a probe function.
810
Mathieu Desnoyersfb32e032008-02-02 15:10:33 -0500811source "arch/Kconfig"
812
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813endmenu # General setup
814
Dmitry Baryshkovee7e5512008-06-29 14:18:46 +0400815config HAVE_GENERIC_DMA_COHERENT
816 bool
817 default n
818
Linus Torvalds158a9622008-01-02 13:04:48 -0800819config SLABINFO
820 bool
821 depends on PROC_FS
Christoph Lameter0f389ec2008-04-14 18:53:02 +0300822 depends on SLAB || SLUB_DEBUG
Linus Torvalds158a9622008-01-02 13:04:48 -0800823 default y
824
Chuck Ebbertae81f9e2006-09-16 12:15:53 -0700825config RT_MUTEXES
826 boolean
827 select PLIST
828
Linus Torvalds1da177e2005-04-16 15:20:36 -0700829config TINY_SHMEM
830 default !SHMEM
831 bool
832
833config BASE_SMALL
834 int
835 default 0 if BASE_FULL
836 default 1 if !BASE_FULL
837
Jan Engelhardt66da5732007-07-15 23:39:29 -0700838menuconfig MODULES
Linus Torvalds1da177e2005-04-16 15:20:36 -0700839 bool "Enable loadable module support"
840 help
841 Kernel modules are small pieces of compiled code which can
842 be inserted in the running kernel, rather than being
843 permanently built into the kernel. You use the "modprobe"
844 tool to add (and sometimes remove) them. If you say Y here,
845 many parts of the kernel can be built as modules (by
846 answering M instead of Y where indicated): this is most
847 useful for infrequently used options which are not required
848 for booting. For more information, see the man pages for
849 modprobe, lsmod, modinfo, insmod and rmmod.
850
851 If you say Y here, you will need to run "make
852 modules_install" to put the modules under /lib/modules/
853 where modprobe can find them (you may need to be root to do
854 this).
855
856 If unsure, say Y.
857
Robert P. J. Day0b0de142008-08-04 13:31:32 -0400858if MODULES
859
Linus Torvalds826e4502008-05-04 17:04:16 -0700860config MODULE_FORCE_LOAD
861 bool "Forced module loading"
Linus Torvalds826e4502008-05-04 17:04:16 -0700862 default n
863 help
Rusty Russell91e37a72008-05-09 16:25:28 +1000864 Allow loading of modules without version information (ie. modprobe
865 --force). Forced module loading sets the 'F' (forced) taint flag and
866 is usually a really bad idea.
Linus Torvalds826e4502008-05-04 17:04:16 -0700867
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868config MODULE_UNLOAD
869 bool "Module unloading"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 help
871 Without this option you will not be able to unload any
872 modules (note that some modules may not be unloadable
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500873 anyway), which makes your kernel smaller, faster
874 and simpler. If unsure, say Y.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875
876config MODULE_FORCE_UNLOAD
877 bool "Forced module unloading"
878 depends on MODULE_UNLOAD && EXPERIMENTAL
879 help
880 This option allows you to force a module to unload, even if the
881 kernel believes it is unsafe: the kernel will remove the module
882 without waiting for anyone to stop using it (using the -f option to
883 rmmod). This is mainly for kernel developers and desperate users.
884 If unsure, say N.
885
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886config MODVERSIONS
Sam Ravnborg0d541642005-12-26 23:04:02 +0100887 bool "Module versioning support"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888 help
889 Usually, you have to use modules compiled with your kernel.
890 Saying Y here makes it sometimes possible to use modules
891 compiled for different kernels, by adding enough information
892 to the modules to (hopefully) spot any changes which would
893 make them incompatible with the kernel you are running. If
894 unsure, say N.
895
896config MODULE_SRCVERSION_ALL
897 bool "Source checksum for all modules"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898 help
899 Modules which contain a MODULE_VERSION get an extra "srcversion"
900 field inserted into their modinfo section, which contains a
901 sum of the source files which made it. This helps maintainers
902 see exactly which source was used to build a module (since
903 others sometimes change the module source without updating
904 the version). With this option, such a "srcversion" field
905 will be created for all modules. If unsure, say N.
906
907config KMOD
Johannes Bergbaabaae2008-07-08 19:00:16 +0200908 def_bool y
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 help
Johannes Bergbaabaae2008-07-08 19:00:16 +0200910 This is being removed soon. These days, CONFIG_MODULES
911 implies CONFIG_KMOD, so use that instead.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700912
Robert P. J. Day0b0de142008-08-04 13:31:32 -0400913endif # MODULES
914
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915config STOP_MACHINE
916 bool
917 default y
918 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
919 help
920 Need stop_machine() primitive.
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100921
Jens Axboe3a65dfe2005-11-04 08:43:35 +0100922source "block/Kconfig"
Avi Kivitye98c3202007-10-16 23:27:31 -0700923
924config PREEMPT_NOTIFIERS
925 bool
Paul E. McKenneye260be62008-01-25 21:08:24 +0100926
Paul E. McKenneye260be62008-01-25 21:08:24 +0100927config CLASSIC_RCU
Paul E. McKenney21bbb392008-03-10 11:43:57 -0700928 def_bool !PREEMPT_RCU
Paul E. McKenneye260be62008-01-25 21:08:24 +0100929 help
930 This option selects the classic RCU implementation that is
931 designed for best read-side performance on non-realtime
Paul E. McKenney21bbb392008-03-10 11:43:57 -0700932 systems. Classic RCU is the default. Note that the
933 PREEMPT_RCU symbol is used to select/deselect this option.