| blob | ad33c979e0b32d3e2f2c1a21bc641003b02ad1fd |
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33 drivers that have been replaced by something else, and/or are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 TASK_XACCT
196 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
197 depends on TASKSTATS
198 help
199 Collect extended task accounting data and send the data
200 to userland for processing over the taskstats interface.
202 Say N if unsure.
204 config TASK_IO_ACCOUNTING
205 bool "Enable per-task storage I/O accounting (EXPERIMENTAL)"
206 depends on TASK_XACCT
207 help
208 Collect information on the number of bytes of storage I/O which this
209 task has caused.
211 Say N if unsure.
213 config UTS_NS
214 bool "UTS Namespaces"
215 default n
216 help
217 Support uts namespaces. This allows containers, i.e.
218 vservers, to use uts namespaces to provide different
219 uts info for different servers. If unsure, say N.
221 config AUDIT
222 bool "Auditing support"
223 depends on NET
224 help
225 Enable auditing infrastructure that can be used with another
226 kernel subsystem, such as SELinux (which requires this for
227 logging of avc messages output). Does not do system-call
228 auditing without CONFIG_AUDITSYSCALL.
230 config AUDITSYSCALL
231 bool "Enable system-call auditing support"
232 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64)
233 default y if SECURITY_SELINUX
234 help
235 Enable low-overhead system-call auditing infrastructure that
236 can be used independently or with another kernel subsystem,
237 such as SELinux. To use audit's filesystem watch feature, please
238 ensure that INOTIFY is configured.
240 config IKCONFIG
241 tristate "Kernel .config support"
242 ---help---
243 This option enables the complete Linux kernel ".config" file
244 contents to be saved in the kernel. It provides documentation
245 of which kernel options are used in a running kernel or in an
246 on-disk kernel. This information can be extracted from the kernel
247 image file with the script scripts/extract-ikconfig and used as
248 input to rebuild the current kernel or to build another kernel.
249 It can also be extracted from a running kernel by reading
250 /proc/config.gz if enabled (below).
252 config IKCONFIG_PROC
253 bool "Enable access to .config through /proc/config.gz"
254 depends on IKCONFIG && PROC_FS
255 ---help---
256 This option enables access to the kernel configuration file
257 through /proc/config.gz.
259 config CPUSETS
260 bool "Cpuset support"
261 depends on SMP
262 help
263 This option will let you create and manage CPUSETs which
264 allow dynamically partitioning a system into sets of CPUs and
265 Memory Nodes and assigning tasks to run only within those sets.
266 This is primarily useful on large SMP or NUMA systems.
268 Say N if unsure.
270 config SYSFS_DEPRECATED
271 bool "Create deprecated sysfs files"
272 default y
273 help
274 This option creates deprecated symlinks such as the
275 "device"-link, the <subsystem>:<name>-link, and the
276 "bus"-link. It may also add deprecated key in the
277 uevent environment.
278 None of these features or values should be used today, as
279 they export driver core implementation details to userspace
280 or export properties which can't be kept stable across kernel
281 releases.
283 If enabled, this option will also move any device structures
284 that belong to a class, back into the /sys/class heirachy, in
285 order to support older versions of udev.
287 If you are using a distro that was released in 2006 or later,
288 it should be safe to say N here.
290 config RELAY
291 bool "Kernel->user space relay support (formerly relayfs)"
292 help
293 This option enables support for relay interface support in
294 certain file systems (such as debugfs).
295 It is designed to provide an efficient mechanism for tools and
296 facilities to relay large amounts of data from kernel space to
297 user space.
299 If unsure, say N.
301 if BLK_DEV_INITRD
303 source "usr/Kconfig"
305 endif
307 config CC_OPTIMIZE_FOR_SIZE
308 bool "Optimize for size (Look out for broken compilers!)"
309 default y
310 depends on ARM || H8300 || EXPERIMENTAL
311 help
312 Enabling this option will pass "-Os" instead of "-O2" to gcc
313 resulting in a smaller kernel.
315 WARNING: some versions of gcc may generate incorrect code with this
316 option. If problems are observed, a gcc upgrade may be needed.
318 If unsure, say N.
320 config SYSCTL
321 bool
323 menuconfig EMBEDDED
324 bool "Configure standard kernel features (for small systems)"
325 help
326 This option allows certain base kernel options and settings
327 to be disabled or tweaked. This is for specialized
328 environments which can tolerate a "non-standard" kernel.
329 Only use this if you really know what you are doing.
331 config UID16
332 bool "Enable 16-bit UID system calls" if EMBEDDED
333 depends on ARM || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
334 default y
335 help
336 This enables the legacy 16-bit UID syscall wrappers.
338 config SYSCTL_SYSCALL
339 bool "Sysctl syscall support" if EMBEDDED
340 default y
341 select SYSCTL
342 ---help---
343 sys_sysctl uses binary paths that have been found challenging
344 to properly maintain and use. The interface in /proc/sys
345 using paths with ascii names is now the primary path to this
346 information.
348 Almost nothing using the binary sysctl interface so if you are
349 trying to save some space it is probably safe to disable this,
350 making your kernel marginally smaller.
352 If unsure say Y here.
354 config KALLSYMS
355 bool "Load all symbols for debugging/ksymoops" if EMBEDDED
356 default y
357 help
358 Say Y here to let the kernel print out symbolic crash information and
359 symbolic stack backtraces. This increases the size of the kernel
360 somewhat, as all symbols have to be loaded into the kernel image.
362 config KALLSYMS_ALL
363 bool "Include all symbols in kallsyms"
364 depends on DEBUG_KERNEL && KALLSYMS
365 help
366 Normally kallsyms only contains the symbols of functions, for nicer
367 OOPS messages. Some debuggers can use kallsyms for other
368 symbols too: say Y here to include all symbols, if you need them
369 and you don't care about adding 300k to the size of your kernel.
371 Say N.
373 config KALLSYMS_EXTRA_PASS
374 bool "Do an extra kallsyms pass"
375 depends on KALLSYMS
376 help
377 If kallsyms is not working correctly, the build will fail with
378 inconsistent kallsyms data. If that occurs, log a bug report and
379 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
380 Always say N here unless you find a bug in kallsyms, which must be
381 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
382 you wait for kallsyms to be fixed.
385 config HOTPLUG
386 bool "Support for hot-pluggable devices" if EMBEDDED
387 default y
388 help
389 This option is provided for the case where no hotplug or uevent
390 capabilities is wanted by the kernel. You should only consider
391 disabling this option for embedded systems that do not use modules, a
392 dynamic /dev tree, or dynamic device discovery. Just say Y.
394 config PRINTK
395 default y
396 bool "Enable support for printk" if EMBEDDED
397 help
398 This option enables normal printk support. Removing it
399 eliminates most of the message strings from the kernel image
400 and makes the kernel more or less silent. As this makes it
401 very difficult to diagnose system problems, saying N here is
402 strongly discouraged.
404 config BUG
405 bool "BUG() support" if EMBEDDED
406 default y
407 help
408 Disabling this option eliminates support for BUG and WARN, reducing
409 the size of your kernel image and potentially quietly ignoring
410 numerous fatal conditions. You should only consider disabling this
411 option for embedded systems with no facilities for reporting errors.
412 Just say Y.
414 config ELF_CORE
415 default y
416 bool "Enable ELF core dumps" if EMBEDDED
417 help
418 Enable support for generating core dumps. Disabling saves about 4k.
420 config BASE_FULL
421 default y
422 bool "Enable full-sized data structures for core" if EMBEDDED
423 help
424 Disabling this option reduces the size of miscellaneous core
425 kernel data structures. This saves memory on small machines,
426 but may reduce performance.
428 config FUTEX
429 bool "Enable futex support" if EMBEDDED
430 default y
431 select RT_MUTEXES
432 help
433 Disabling this option will cause the kernel to be built without
434 support for "fast userspace mutexes". The resulting kernel may not
435 run glibc-based applications correctly.
437 config EPOLL
438 bool "Enable eventpoll support" if EMBEDDED
439 default y
440 help
441 Disabling this option will cause the kernel to be built without
442 support for epoll family of system calls.
444 config SHMEM
445 bool "Use full shmem filesystem" if EMBEDDED
446 default y
447 depends on MMU
448 help
449 The shmem is an internal filesystem used to manage shared memory.
450 It is backed by swap and manages resource limits. It is also exported
451 to userspace as tmpfs if TMPFS is enabled. Disabling this
452 option replaces shmem and tmpfs with the much simpler ramfs code,
453 which may be appropriate on small systems without swap.
455 config SLAB
456 default y
457 bool "Use full SLAB allocator" if (EMBEDDED && !SMP && !SPARSEMEM)
458 help
459 Disabling this replaces the advanced SLAB allocator and
460 kmalloc support with the drastically simpler SLOB allocator.
461 SLOB is more space efficient but does not scale well and is
462 more susceptible to fragmentation.
464 config VM_EVENT_COUNTERS
465 default y
466 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
467 help
468 VM event counters are needed for event counts to be shown.
469 This option allows the disabling of the VM event counters
470 on EMBEDDED systems. /proc/vmstat will only show page counts
471 if VM event counters are disabled.
473 endmenu # General setup
475 config RT_MUTEXES
476 boolean
477 select PLIST
479 config TINY_SHMEM
480 default !SHMEM
481 bool
483 config BASE_SMALL
484 int
485 default 0 if BASE_FULL
486 default 1 if !BASE_FULL
488 config SLOB
489 default !SLAB
490 bool
492 menu "Loadable module support"
494 config MODULES
495 bool "Enable loadable module support"
496 help
497 Kernel modules are small pieces of compiled code which can
498 be inserted in the running kernel, rather than being
499 permanently built into the kernel. You use the "modprobe"
500 tool to add (and sometimes remove) them. If you say Y here,
501 many parts of the kernel can be built as modules (by
502 answering M instead of Y where indicated): this is most
503 useful for infrequently used options which are not required
504 for booting. For more information, see the man pages for
505 modprobe, lsmod, modinfo, insmod and rmmod.
507 If you say Y here, you will need to run "make
508 modules_install" to put the modules under /lib/modules/
509 where modprobe can find them (you may need to be root to do
510 this).
512 If unsure, say Y.
514 config MODULE_UNLOAD
515 bool "Module unloading"
516 depends on MODULES
517 help
518 Without this option you will not be able to unload any
519 modules (note that some modules may not be unloadable
520 anyway), which makes your kernel slightly smaller and
521 simpler. If unsure, say Y.
523 config MODULE_FORCE_UNLOAD
524 bool "Forced module unloading"
525 depends on MODULE_UNLOAD && EXPERIMENTAL
526 help
527 This option allows you to force a module to unload, even if the
528 kernel believes it is unsafe: the kernel will remove the module
529 without waiting for anyone to stop using it (using the -f option to
530 rmmod). This is mainly for kernel developers and desperate users.
531 If unsure, say N.
533 config MODVERSIONS
534 bool "Module versioning support"
535 depends on MODULES
536 help
537 Usually, you have to use modules compiled with your kernel.
538 Saying Y here makes it sometimes possible to use modules
539 compiled for different kernels, by adding enough information
540 to the modules to (hopefully) spot any changes which would
541 make them incompatible with the kernel you are running. If
542 unsure, say N.
544 config MODULE_SRCVERSION_ALL
545 bool "Source checksum for all modules"
546 depends on MODULES
547 help
548 Modules which contain a MODULE_VERSION get an extra "srcversion"
549 field inserted into their modinfo section, which contains a
550 sum of the source files which made it. This helps maintainers
551 see exactly which source was used to build a module (since
552 others sometimes change the module source without updating
553 the version). With this option, such a "srcversion" field
554 will be created for all modules. If unsure, say N.
556 config KMOD
557 bool "Automatic kernel module loading"
558 depends on MODULES
559 help
560 Normally when you have selected some parts of the kernel to
561 be created as kernel modules, you must load them (using the
562 "modprobe" command) before you can use them. If you say Y
563 here, some parts of the kernel will be able to load modules
564 automatically: when a part of the kernel needs a module, it
565 runs modprobe with the appropriate arguments, thereby
566 loading the module if it is available. If unsure, say Y.
568 config STOP_MACHINE
569 bool
570 default y
571 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
572 help
573 Need stop_machine() primitive.
574 endmenu
576 menu "Block layer"
577 source "block/Kconfig"
578 endmenu