| blob | b322922e68036bbe86c7acd3c2f1ee8ed2b86487 |
1 config DEFCONFIG_LIST
2 string
3 depends on !UML
4 option defconfig_list
5 default "/lib/modules/$UNAME_RELEASE/.config"
6 default "/etc/kernel-config"
7 default "/boot/config-$UNAME_RELEASE"
8 default "arch/$ARCH/defconfig"
10 menu "Code maturity level options"
12 config EXPERIMENTAL
13 bool "Prompt for development and/or incomplete code/drivers"
14 ---help---
15 Some of the various things that Linux supports (such as network
16 drivers, file systems, network protocols, etc.) can be in a state
17 of development where the functionality, stability, or the level of
18 testing is not yet high enough for general use. This is usually
19 known as the "alpha-test" phase among developers. If a feature is
20 currently in alpha-test, then the developers usually discourage
21 uninformed widespread use of this feature by the general public to
22 avoid "Why doesn't this work?" type mail messages. However, active
23 testing and use of these systems is welcomed. Just be aware that it
24 may not meet the normal level of reliability or it may fail to work
25 in some special cases. Detailed bug reports from people familiar
26 with the kernel internals are usually welcomed by the developers
27 (before submitting bug reports, please read the documents
28 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
29 <file:Documentation/BUG-HUNTING>, and
30 <file:Documentation/oops-tracing.txt> in the kernel source).
32 This option will also make obsoleted drivers available. These are
33 drivers that have been replaced by something else, and/or are
34 scheduled to be removed in a future kernel release.
36 Unless you intend to help test and develop a feature or driver that
37 falls into this category, or you have a situation that requires
38 using these features, you should probably say N here, which will
39 cause the configurator to present you with fewer choices. If
40 you say Y here, you will be offered the choice of using features or
41 drivers that are currently considered to be in the alpha-test phase.
43 config BROKEN
44 bool
46 config BROKEN_ON_SMP
47 bool
48 depends on BROKEN || !SMP
49 default y
51 config LOCK_KERNEL
52 bool
53 depends on SMP || PREEMPT
54 default y
56 config INIT_ENV_ARG_LIMIT
57 int
58 default 32 if !UML
59 default 128 if UML
60 help
61 Maximum of each of the number of arguments and environment
62 variables passed to init from the kernel command line.
64 endmenu
66 menu "General setup"
68 config LOCALVERSION
69 string "Local version - append to kernel release"
70 help
71 Append an extra string to the end of your kernel version.
72 This will show up when you type uname, for example.
73 The string you set here will be appended after the contents of
74 any files with a filename matching localversion* in your
75 object and source tree, in that order. Your total string can
76 be a maximum of 64 characters.
78 config LOCALVERSION_AUTO
79 bool "Automatically append version information to the version string"
80 default y
81 help
82 This will try to automatically determine if the current tree is a
83 release tree by looking for git tags that
84 belong to the current top of tree revision.
86 A string of the format -gxxxxxxxx will be added to the localversion
87 if a git based tree is found. The string generated by this will be
88 appended after any matching localversion* files, and after the value
89 set in CONFIG_LOCALVERSION
91 Note: This requires Perl, and a git repository, but not necessarily
92 the git or cogito tools to be installed.
94 config SWAP
95 bool "Support for paging of anonymous memory (swap)"
96 depends on MMU && BLOCK
97 default y
98 help
99 This option allows you to choose whether you want to have support
100 for so called swap devices or swap files in your kernel that are
101 used to provide more virtual memory than the actual RAM present
102 in your computer. If unsure say Y.
104 config SYSVIPC
105 bool "System V IPC"
106 ---help---
107 Inter Process Communication is a suite of library functions and
108 system calls which let processes (running programs) synchronize and
109 exchange information. It is generally considered to be a good thing,
110 and some programs won't run unless you say Y here. In particular, if
111 you want to run the DOS emulator dosemu under Linux (read the
112 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
113 you'll need to say Y here.
115 You can find documentation about IPC with "info ipc" and also in
116 section 6.4 of the Linux Programmer's Guide, available from
117 <http://www.tldp.org/guides.html>.
119 config IPC_NS
120 bool "IPC Namespaces"
121 depends on SYSVIPC
122 default n
123 help
124 Support ipc namespaces. This allows containers, i.e. virtual
125 environments, to use ipc namespaces to provide different ipc
126 objects for different servers. If unsure, say N.
128 config POSIX_MQUEUE
129 bool "POSIX Message Queues"
130 depends on NET && EXPERIMENTAL
131 ---help---
132 POSIX variant of message queues is a part of IPC. In POSIX message
133 queues every message has a priority which decides about succession
134 of receiving it by a process. If you want to compile and run
135 programs written e.g. for Solaris with use of its POSIX message
136 queues (functions mq_*) say Y here. To use this feature you will
137 also need mqueue library, available from
138 <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
140 POSIX message queues are visible as a filesystem called 'mqueue'
141 and can be mounted somewhere if you want to do filesystem
142 operations on message queues.
144 If unsure, say Y.
146 config BSD_PROCESS_ACCT
147 bool "BSD Process Accounting"
148 help
149 If you say Y here, a user level program will be able to instruct the
150 kernel (via a special system call) to write process accounting
151 information to a file: whenever a process exits, information about
152 that process will be appended to the file by the kernel. The
153 information includes things such as creation time, owning user,
154 command name, memory usage, controlling terminal etc. (the complete
155 list is in the struct acct in <file:include/linux/acct.h>). It is
156 up to the user level program to do useful things with this
157 information. This is generally a good idea, so say Y.
159 config BSD_PROCESS_ACCT_V3
160 bool "BSD Process Accounting version 3 file format"
161 depends on BSD_PROCESS_ACCT
162 default n
163 help
164 If you say Y here, the process accounting information is written
165 in a new file format that also logs the process IDs of each
166 process and it's parent. Note that this file format is incompatible
167 with previous v0/v1/v2 file formats, so you will need updated tools
168 for processing it. A preliminary version of these tools is available
169 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
171 config TASKSTATS
172 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
173 depends on NET
174 default n
175 help
176 Export selected statistics for tasks/processes through the
177 generic netlink interface. Unlike BSD process accounting, the
178 statistics are available during the lifetime of tasks/processes as
179 responses to commands. Like BSD accounting, they are sent to user
180 space on task exit.
182 Say N if unsure.
184 config TASK_DELAY_ACCT
185 bool "Enable per-task delay accounting (EXPERIMENTAL)"
186 depends on TASKSTATS
187 help
188 Collect information on time spent by a task waiting for system
189 resources like cpu, synchronous block I/O completion and swapping
190 in pages. Such statistics can help in setting a task's priorities
191 relative to other tasks for cpu, io, rss limits etc.
193 Say N if unsure.
195 config UTS_NS
196 bool "UTS Namespaces"
197 default n
198 help
199 Support uts namespaces. This allows containers, i.e.
200 vservers, to use uts namespaces to provide different
201 uts info for different servers. If unsure, say N.
203 config AUDIT
204 bool "Auditing support"
205 depends on NET
206 help
207 Enable auditing infrastructure that can be used with another
208 kernel subsystem, such as SELinux (which requires this for
209 logging of avc messages output). Does not do system-call
210 auditing without CONFIG_AUDITSYSCALL.
212 config AUDITSYSCALL
213 bool "Enable system-call auditing support"
214 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64)
215 default y if SECURITY_SELINUX
216 help
217 Enable low-overhead system-call auditing infrastructure that
218 can be used independently or with another kernel subsystem,
219 such as SELinux. To use audit's filesystem watch feature, please
220 ensure that INOTIFY is configured.
222 config IKCONFIG
223 tristate "Kernel .config support"
224 ---help---
225 This option enables the complete Linux kernel ".config" file
226 contents to be saved in the kernel. It provides documentation
227 of which kernel options are used in a running kernel or in an
228 on-disk kernel. This information can be extracted from the kernel
229 image file with the script scripts/extract-ikconfig and used as
230 input to rebuild the current kernel or to build another kernel.
231 It can also be extracted from a running kernel by reading
232 /proc/config.gz if enabled (below).
234 config MINIMAL_OOPS
235 bool "Minimal Oopses"
236 depends on ARM
238 config IKCONFIG_PROC
239 bool "Enable access to .config through /proc/config.gz"
240 depends on IKCONFIG && PROC_FS
241 ---help---
242 This option enables access to the kernel configuration file
243 through /proc/config.gz.
245 config CPUSETS
246 bool "Cpuset support"
247 depends on SMP
248 help
249 This option will let you create and manage CPUSETs which
250 allow dynamically partitioning a system into sets of CPUs and
251 Memory Nodes and assigning tasks to run only within those sets.
252 This is primarily useful on large SMP or NUMA systems.
254 Say N if unsure.
256 config SYSFS_DEPRECATED
257 bool "Create deprecated sysfs files"
258 default y
259 help
260 This option creates deprecated symlinks such as the
261 "device"-link, the <subsystem>:<name>-link, and the
262 "bus"-link. It may also add deprecated key in the
263 uevent environment.
264 None of these features or values should be used today, as
265 they export driver core implementation details to userspace
266 or export properties which can't be kept stable across kernel
267 releases.
269 If enabled, this option will also move any device structures
270 that belong to a class, back into the /sys/class heirachy, in
271 order to support older versions of udev.
273 If you are using a distro that was released in 2006 or later,
274 it should be safe to say N here.
276 config RELAY
277 bool "Kernel->user space relay support (formerly relayfs)"
278 help
279 This option enables support for relay interface support in
280 certain file systems (such as debugfs).
281 It is designed to provide an efficient mechanism for tools and
282 facilities to relay large amounts of data from kernel space to
283 user space.
285 If unsure, say N.
287 source "usr/Kconfig"
289 config CC_OPTIMIZE_FOR_SIZE
290 bool "Optimize for size (Look out for broken compilers!)"
291 default y
292 depends on ARM || H8300 || EXPERIMENTAL
293 help
294 Enabling this option will pass "-Os" instead of "-O2" to gcc
295 resulting in a smaller kernel.
297 WARNING: some versions of gcc may generate incorrect code with this
298 option. If problems are observed, a gcc upgrade may be needed.
300 If unsure, say N.
302 config TASK_XACCT
303 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
304 depends on TASKSTATS
305 help
306 Collect extended task accounting data and send the data
307 to userland for processing over the taskstats interface.
309 Say N if unsure.
311 config SYSCTL
312 bool
314 menuconfig EMBEDDED
315 bool "Configure standard kernel features (for small systems)"
316 help
317 This option allows certain base kernel options and settings
318 to be disabled or tweaked. This is for specialized
319 environments which can tolerate a "non-standard" kernel.
320 Only use this if you really know what you are doing.
322 config UID16
323 bool "Enable 16-bit UID system calls" if EMBEDDED
324 depends on ARM || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
325 default y
326 help
327 This enables the legacy 16-bit UID syscall wrappers.
329 config SYSCTL_SYSCALL
330 bool "Sysctl syscall support" if EMBEDDED
331 default y
332 select SYSCTL
333 ---help---
334 sys_sysctl uses binary paths that have been found challenging
335 to properly maintain and use. The interface in /proc/sys
336 using paths with ascii names is now the primary path to this
337 information.
339 Almost nothing using the binary sysctl interface so if you are
340 trying to save some space it is probably safe to disable this,
341 making your kernel marginally smaller.
343 If unsure say Y here.
345 config KALLSYMS
346 bool "Load all symbols for debugging/kksymoops" if EMBEDDED
347 default y
348 help
349 Say Y here to let the kernel print out symbolic crash information and
350 symbolic stack backtraces. This increases the size of the kernel
351 somewhat, as all symbols have to be loaded into the kernel image.
353 config KALLSYMS_ALL
354 bool "Include all symbols in kallsyms"
355 depends on DEBUG_KERNEL && KALLSYMS
356 help
357 Normally kallsyms only contains the symbols of functions, for nicer
358 OOPS messages. Some debuggers can use kallsyms for other
359 symbols too: say Y here to include all symbols, if you need them
360 and you don't care about adding 300k to the size of your kernel.
362 Say N.
364 config KALLSYMS_EXTRA_PASS
365 bool "Do an extra kallsyms pass"
366 depends on KALLSYMS
367 help
368 If kallsyms is not working correctly, the build will fail with
369 inconsistent kallsyms data. If that occurs, log a bug report and
370 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
371 Always say N here unless you find a bug in kallsyms, which must be
372 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
373 you wait for kallsyms to be fixed.
376 config HOTPLUG
377 bool "Support for hot-pluggable devices" if EMBEDDED
378 default y
379 help
380 This option is provided for the case where no hotplug or uevent
381 capabilities is wanted by the kernel. You should only consider
382 disabling this option for embedded systems that do not use modules, a
383 dynamic /dev tree, or dynamic device discovery. Just say Y.
385 config PRINTK
386 default y
387 bool "Enable support for printk" if EMBEDDED
388 help
389 This option enables normal printk support. Removing it
390 eliminates most of the message strings from the kernel image
391 and makes the kernel more or less silent. As this makes it
392 very difficult to diagnose system problems, saying N here is
393 strongly discouraged.
395 config BUG
396 bool "BUG() support" if EMBEDDED
397 default y
398 help
399 Disabling this option eliminates support for BUG and WARN, reducing
400 the size of your kernel image and potentially quietly ignoring
401 numerous fatal conditions. You should only consider disabling this
402 option for embedded systems with no facilities for reporting errors.
403 Just say Y.
405 config ELF_CORE
406 default y
407 bool "Enable ELF core dumps" if EMBEDDED
408 help
409 Enable support for generating core dumps. Disabling saves about 4k.
411 config BASE_FULL
412 default y
413 bool "Enable full-sized data structures for core" if EMBEDDED
414 help
415 Disabling this option reduces the size of miscellaneous core
416 kernel data structures. This saves memory on small machines,
417 but may reduce performance.
419 config FUTEX
420 bool "Enable futex support" if EMBEDDED
421 default y
422 select RT_MUTEXES
423 help
424 Disabling this option will cause the kernel to be built without
425 support for "fast userspace mutexes". The resulting kernel may not
426 run glibc-based applications correctly.
428 config EPOLL
429 bool "Enable eventpoll support" if EMBEDDED
430 default y
431 help
432 Disabling this option will cause the kernel to be built without
433 support for epoll family of system calls.
435 config SHMEM
436 bool "Use full shmem filesystem" if EMBEDDED
437 default y
438 depends on MMU
439 help
440 The shmem is an internal filesystem used to manage shared memory.
441 It is backed by swap and manages resource limits. It is also exported
442 to userspace as tmpfs if TMPFS is enabled. Disabling this
443 option replaces shmem and tmpfs with the much simpler ramfs code,
444 which may be appropriate on small systems without swap.
446 config USELIB
447 default y
448 bool "Support uselib() shared libraries" if EMBEDDED
450 config CORE_DUMP
451 default y
452 bool "Support core dumps" if EMBEDDED
454 config SLAB
455 default y
456 bool "Use full SLAB allocator" if EMBEDDED
457 help
458 Disabling this replaces the advanced SLAB allocator and
459 kmalloc support with the drastically simpler SLOB allocator.
460 SLOB is more space efficient but does not scale well and is
461 more susceptible to fragmentation.
463 config VM_EVENT_COUNTERS
464 default y
465 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
466 help
467 VM event counters are only needed to for event counts to be
468 shown. They have no function for the kernel itself. This
469 option allows the disabling of the VM event counters.
470 /proc/vmstat will only show page counts.
472 endmenu # General setup
474 config RT_MUTEXES
475 boolean
476 select PLIST
478 config TINY_SHMEM
479 default !SHMEM
480 bool
482 config BASE_SMALL
483 int
484 default 0 if BASE_FULL
485 default 1 if !BASE_FULL
487 config SLOB
488 default !SLAB
489 bool
491 menu "Loadable module support"
493 config MODULES
494 bool "Enable loadable module support"
495 help
496 Kernel modules are small pieces of compiled code which can
497 be inserted in the running kernel, rather than being
498 permanently built into the kernel. You use the "modprobe"
499 tool to add (and sometimes remove) them. If you say Y here,
500 many parts of the kernel can be built as modules (by
501 answering M instead of Y where indicated): this is most
502 useful for infrequently used options which are not required
503 for booting. For more information, see the man pages for
504 modprobe, lsmod, modinfo, insmod and rmmod.
506 If you say Y here, you will need to run "make
507 modules_install" to put the modules under /lib/modules/
508 where modprobe can find them (you may need to be root to do
509 this).
511 If unsure, say Y.
513 config MODULE_UNLOAD
514 bool "Module unloading"
515 depends on MODULES
516 help
517 Without this option you will not be able to unload any
518 modules (note that some modules may not be unloadable
519 anyway), which makes your kernel slightly smaller and
520 simpler. If unsure, say Y.
522 config MODULE_FORCE_UNLOAD
523 bool "Forced module unloading"
524 depends on MODULE_UNLOAD && EXPERIMENTAL
525 help
526 This option allows you to force a module to unload, even if the
527 kernel believes it is unsafe: the kernel will remove the module
528 without waiting for anyone to stop using it (using the -f option to
529 rmmod). This is mainly for kernel developers and desperate users.
530 If unsure, say N.
532 config MODVERSIONS
533 bool "Module versioning support"
534 depends on MODULES
535 help
536 Usually, you have to use modules compiled with your kernel.
537 Saying Y here makes it sometimes possible to use modules
538 compiled for different kernels, by adding enough information
539 to the modules to (hopefully) spot any changes which would
540 make them incompatible with the kernel you are running. If
541 unsure, say N.
543 config MODULE_SRCVERSION_ALL
544 bool "Source checksum for all modules"
545 depends on MODULES
546 help
547 Modules which contain a MODULE_VERSION get an extra "srcversion"
548 field inserted into their modinfo section, which contains a
549 sum of the source files which made it. This helps maintainers
550 see exactly which source was used to build a module (since
551 others sometimes change the module source without updating
552 the version). With this option, such a "srcversion" field
553 will be created for all modules. If unsure, say N.
555 config KMOD
556 bool "Automatic kernel module loading"
557 depends on MODULES
558 help
559 Normally when you have selected some parts of the kernel to
560 be created as kernel modules, you must load them (using the
561 "modprobe" command) before you can use them. If you say Y
562 here, some parts of the kernel will be able to load modules
563 automatically: when a part of the kernel needs a module, it
564 runs modprobe with the appropriate arguments, thereby
565 loading the module if it is available. If unsure, say Y.
567 config STOP_MACHINE
568 bool
569 default y
570 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
571 help
572 Need stop_machine() primitive.
573 endmenu
575 menu "Block layer"
576 source "block/Kconfig"
577 endmenu