[PATCH] uml: reenable compilation of enable_timer, disabled by mistake
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / init / Kconfig
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1config DEFCONFIG_LIST
2 string
3 option defconfig_list
4 default "/lib/modules/$UNAME_RELEASE/.config"
5 default "/etc/kernel-config"
6 default "/boot/config-$UNAME_RELEASE"
7 default "arch/$ARCH/defconfig"
8
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9menu "Code maturity level options"
10
11config EXPERIMENTAL
12 bool "Prompt for development and/or incomplete code/drivers"
13 ---help---
14 Some of the various things that Linux supports (such as network
15 drivers, file systems, network protocols, etc.) can be in a state
16 of development where the functionality, stability, or the level of
17 testing is not yet high enough for general use. This is usually
18 known as the "alpha-test" phase among developers. If a feature is
19 currently in alpha-test, then the developers usually discourage
20 uninformed widespread use of this feature by the general public to
21 avoid "Why doesn't this work?" type mail messages. However, active
22 testing and use of these systems is welcomed. Just be aware that it
23 may not meet the normal level of reliability or it may fail to work
24 in some special cases. Detailed bug reports from people familiar
25 with the kernel internals are usually welcomed by the developers
26 (before submitting bug reports, please read the documents
27 <file:README>, <file:MAINTAINERS>, <file:REPORTING-BUGS>,
28 <file:Documentation/BUG-HUNTING>, and
29 <file:Documentation/oops-tracing.txt> in the kernel source).
30
31 This option will also make obsoleted drivers available. These are
32 drivers that have been replaced by something else, and/or are
33 scheduled to be removed in a future kernel release.
34
35 Unless you intend to help test and develop a feature or driver that
36 falls into this category, or you have a situation that requires
37 using these features, you should probably say N here, which will
38 cause the configurator to present you with fewer choices. If
39 you say Y here, you will be offered the choice of using features or
40 drivers that are currently considered to be in the alpha-test phase.
41
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42config BROKEN
43 bool
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44
45config BROKEN_ON_SMP
46 bool
47 depends on BROKEN || !SMP
48 default y
49
50config LOCK_KERNEL
51 bool
52 depends on SMP || PREEMPT
53 default y
54
55config INIT_ENV_ARG_LIMIT
56 int
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57 default 32 if !UML
58 default 128 if UML
1da177e4 59 help
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60 Maximum of each of the number of arguments and environment
61 variables passed to init from the kernel command line.
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62
63endmenu
64
65menu "General setup"
66
67config LOCALVERSION
68 string "Local version - append to kernel release"
69 help
70 Append an extra string to the end of your kernel version.
71 This will show up when you type uname, for example.
72 The string you set here will be appended after the contents of
73 any files with a filename matching localversion* in your
74 object and source tree, in that order. Your total string can
75 be a maximum of 64 characters.
76
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77config LOCALVERSION_AUTO
78 bool "Automatically append version information to the version string"
79 default y
80 help
81 This will try to automatically determine if the current tree is a
82 release tree by looking for git tags that
83 belong to the current top of tree revision.
84
85 A string of the format -gxxxxxxxx will be added to the localversion
86 if a git based tree is found. The string generated by this will be
87 appended after any matching localversion* files, and after the value
88 set in CONFIG_LOCALVERSION
89
90 Note: This requires Perl, and a git repository, but not necessarily
91 the git or cogito tools to be installed.
92
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93config SWAP
94 bool "Support for paging of anonymous memory (swap)"
9361401e 95 depends on MMU && BLOCK
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96 default y
97 help
98 This option allows you to choose whether you want to have support
92c3504e 99 for so called swap devices or swap files in your kernel that are
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100 used to provide more virtual memory than the actual RAM present
101 in your computer. If unsure say Y.
102
103config SYSVIPC
104 bool "System V IPC"
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105 ---help---
106 Inter Process Communication is a suite of library functions and
107 system calls which let processes (running programs) synchronize and
108 exchange information. It is generally considered to be a good thing,
109 and some programs won't run unless you say Y here. In particular, if
110 you want to run the DOS emulator dosemu under Linux (read the
111 DOSEMU-HOWTO, available from <http://www.tldp.org/docs.html#howto>),
112 you'll need to say Y here.
113
114 You can find documentation about IPC with "info ipc" and also in
115 section 6.4 of the Linux Programmer's Guide, available from
116 <http://www.tldp.org/guides.html>.
117
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118config IPC_NS
119 bool "IPC Namespaces"
120 depends on SYSVIPC
121 default n
122 help
123 Support ipc namespaces. This allows containers, i.e. virtual
124 environments, to use ipc namespaces to provide different ipc
125 objects for different servers. If unsure, say N.
126
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127config POSIX_MQUEUE
128 bool "POSIX Message Queues"
129 depends on NET && EXPERIMENTAL
130 ---help---
131 POSIX variant of message queues is a part of IPC. In POSIX message
132 queues every message has a priority which decides about succession
133 of receiving it by a process. If you want to compile and run
134 programs written e.g. for Solaris with use of its POSIX message
135 queues (functions mq_*) say Y here. To use this feature you will
136 also need mqueue library, available from
137 <http://www.mat.uni.torun.pl/~wrona/posix_ipc/>
138
139 POSIX message queues are visible as a filesystem called 'mqueue'
140 and can be mounted somewhere if you want to do filesystem
141 operations on message queues.
142
143 If unsure, say Y.
144
145config BSD_PROCESS_ACCT
146 bool "BSD Process Accounting"
147 help
148 If you say Y here, a user level program will be able to instruct the
149 kernel (via a special system call) to write process accounting
150 information to a file: whenever a process exits, information about
151 that process will be appended to the file by the kernel. The
152 information includes things such as creation time, owning user,
153 command name, memory usage, controlling terminal etc. (the complete
154 list is in the struct acct in <file:include/linux/acct.h>). It is
155 up to the user level program to do useful things with this
156 information. This is generally a good idea, so say Y.
157
158config BSD_PROCESS_ACCT_V3
159 bool "BSD Process Accounting version 3 file format"
160 depends on BSD_PROCESS_ACCT
161 default n
162 help
163 If you say Y here, the process accounting information is written
164 in a new file format that also logs the process IDs of each
165 process and it's parent. Note that this file format is incompatible
166 with previous v0/v1/v2 file formats, so you will need updated tools
167 for processing it. A preliminary version of these tools is available
168 at <http://www.physik3.uni-rostock.de/tim/kernel/utils/acct/>.
169
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170config TASKSTATS
171 bool "Export task/process statistics through netlink (EXPERIMENTAL)"
172 depends on NET
173 default n
174 help
175 Export selected statistics for tasks/processes through the
176 generic netlink interface. Unlike BSD process accounting, the
177 statistics are available during the lifetime of tasks/processes as
178 responses to commands. Like BSD accounting, they are sent to user
179 space on task exit.
180
181 Say N if unsure.
182
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183config TASK_DELAY_ACCT
184 bool "Enable per-task delay accounting (EXPERIMENTAL)"
6f44993f 185 depends on TASKSTATS
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186 help
187 Collect information on time spent by a task waiting for system
188 resources like cpu, synchronous block I/O completion and swapping
189 in pages. Such statistics can help in setting a task's priorities
190 relative to other tasks for cpu, io, rss limits etc.
191
192 Say N if unsure.
193
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194config UTS_NS
195 bool "UTS Namespaces"
196 default n
197 help
198 Support uts namespaces. This allows containers, i.e.
199 vservers, to use uts namespaces to provide different
200 uts info for different servers. If unsure, say N.
201
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202config AUDIT
203 bool "Auditing support"
804a6a49 204 depends on NET
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205 help
206 Enable auditing infrastructure that can be used with another
207 kernel subsystem, such as SELinux (which requires this for
208 logging of avc messages output). Does not do system-call
209 auditing without CONFIG_AUDITSYSCALL.
210
211config AUDITSYSCALL
212 bool "Enable system-call auditing support"
347a8dc3 213 depends on AUDIT && (X86 || PPC || PPC64 || S390 || IA64 || UML || SPARC64)
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214 default y if SECURITY_SELINUX
215 help
216 Enable low-overhead system-call auditing infrastructure that
217 can be used independently or with another kernel subsystem,
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218 such as SELinux. To use audit's filesystem watch feature, please
219 ensure that INOTIFY is configured.
1da177e4 220
1da177e4 221config IKCONFIG
f2443ab6 222 tristate "Kernel .config support"
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223 ---help---
224 This option enables the complete Linux kernel ".config" file
225 contents to be saved in the kernel. It provides documentation
226 of which kernel options are used in a running kernel or in an
227 on-disk kernel. This information can be extracted from the kernel
228 image file with the script scripts/extract-ikconfig and used as
229 input to rebuild the current kernel or to build another kernel.
230 It can also be extracted from a running kernel by reading
231 /proc/config.gz if enabled (below).
232
233config IKCONFIG_PROC
234 bool "Enable access to .config through /proc/config.gz"
235 depends on IKCONFIG && PROC_FS
236 ---help---
237 This option enables access to the kernel configuration file
238 through /proc/config.gz.
239
240config CPUSETS
241 bool "Cpuset support"
242 depends on SMP
243 help
d9fd8a6d 244 This option will let you create and manage CPUSETs which
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245 allow dynamically partitioning a system into sets of CPUs and
246 Memory Nodes and assigning tasks to run only within those sets.
247 This is primarily useful on large SMP or NUMA systems.
248
249 Say N if unsure.
250
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251config RELAY
252 bool "Kernel->user space relay support (formerly relayfs)"
253 help
254 This option enables support for relay interface support in
255 certain file systems (such as debugfs).
256 It is designed to provide an efficient mechanism for tools and
257 facilities to relay large amounts of data from kernel space to
258 user space.
259
260 If unsure, say N.
261
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262source "usr/Kconfig"
263
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264config CC_OPTIMIZE_FOR_SIZE
265 bool "Optimize for size (Look out for broken compilers!)"
266 default y
267 depends on ARM || H8300 || EXPERIMENTAL
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268 help
269 Enabling this option will pass "-Os" instead of "-O2" to gcc
270 resulting in a smaller kernel.
271
272 WARNING: some versions of gcc may generate incorrect code with this
273 option. If problems are observed, a gcc upgrade may be needed.
274
275 If unsure, say N.
276
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277config TASK_XACCT
278 bool "Enable extended accounting over taskstats (EXPERIMENTAL)"
279 depends on TASKSTATS
280 help
281 Collect extended task accounting data and send the data
282 to userland for processing over the taskstats interface.
283
284 Say N if unsure.
285
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286config SYSCTL
287 bool
288
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289menuconfig EMBEDDED
290 bool "Configure standard kernel features (for small systems)"
291 help
292 This option allows certain base kernel options and settings
293 to be disabled or tweaked. This is for specialized
294 environments which can tolerate a "non-standard" kernel.
295 Only use this if you really know what you are doing.
296
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297config UID16
298 bool "Enable 16-bit UID system calls" if EMBEDDED
299 depends on ARM || CRIS || FRV || H8300 || X86_32 || M68K || (S390 && !64BIT) || SUPERH || SPARC32 || (SPARC64 && SPARC32_COMPAT) || UML || (X86_64 && IA32_EMULATION)
300 default y
301 help
302 This enables the legacy 16-bit UID syscall wrappers.
303
b89a8171 304config SYSCTL_SYSCALL
0847062a 305 bool "Sysctl syscall support" if EMBEDDED
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306 default n
307 select SYSCTL
ae81f9e3 308 ---help---
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309 Enable the deprecated sysctl system call. sys_sysctl uses
310 binary paths that have been found to be a major pain to maintain
311 and use. The interface in /proc/sys is now the primary and what
312 everyone uses.
313
0847062a 314 Nothing has been using the binary sysctl interface for some
b89a8171 315 time now so nothing should break if you disable sysctl syscall
0847062a 316 support, and your kernel will get marginally smaller.
b89a8171 317
0847062a 318 Unless you have an application that uses the sys_sysctl interface
b89a8171 319 you should probably say N here.
ae81f9e3 320
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321config KALLSYMS
322 bool "Load all symbols for debugging/kksymoops" if EMBEDDED
323 default y
324 help
325 Say Y here to let the kernel print out symbolic crash information and
326 symbolic stack backtraces. This increases the size of the kernel
327 somewhat, as all symbols have to be loaded into the kernel image.
328
329config KALLSYMS_ALL
330 bool "Include all symbols in kallsyms"
331 depends on DEBUG_KERNEL && KALLSYMS
332 help
333 Normally kallsyms only contains the symbols of functions, for nicer
334 OOPS messages. Some debuggers can use kallsyms for other
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335 symbols too: say Y here to include all symbols, if you need them
336 and you don't care about adding 300k to the size of your kernel.
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337
338 Say N.
339
340config KALLSYMS_EXTRA_PASS
341 bool "Do an extra kallsyms pass"
342 depends on KALLSYMS
343 help
344 If kallsyms is not working correctly, the build will fail with
345 inconsistent kallsyms data. If that occurs, log a bug report and
346 turn on KALLSYMS_EXTRA_PASS which should result in a stable build.
347 Always say N here unless you find a bug in kallsyms, which must be
348 reported. KALLSYMS_EXTRA_PASS is only a temporary workaround while
349 you wait for kallsyms to be fixed.
350
d59745ce 351
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352config HOTPLUG
353 bool "Support for hot-pluggable devices" if EMBEDDED
354 default y
355 help
356 This option is provided for the case where no hotplug or uevent
357 capabilities is wanted by the kernel. You should only consider
358 disabling this option for embedded systems that do not use modules, a
359 dynamic /dev tree, or dynamic device discovery. Just say Y.
360
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361config PRINTK
362 default y
363 bool "Enable support for printk" if EMBEDDED
364 help
365 This option enables normal printk support. Removing it
366 eliminates most of the message strings from the kernel image
367 and makes the kernel more or less silent. As this makes it
368 very difficult to diagnose system problems, saying N here is
369 strongly discouraged.
370
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371config BUG
372 bool "BUG() support" if EMBEDDED
373 default y
374 help
375 Disabling this option eliminates support for BUG and WARN, reducing
376 the size of your kernel image and potentially quietly ignoring
377 numerous fatal conditions. You should only consider disabling this
378 option for embedded systems with no facilities for reporting errors.
379 Just say Y.
380
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381config ELF_CORE
382 default y
383 bool "Enable ELF core dumps" if EMBEDDED
384 help
385 Enable support for generating core dumps. Disabling saves about 4k.
386
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387config BASE_FULL
388 default y
389 bool "Enable full-sized data structures for core" if EMBEDDED
390 help
391 Disabling this option reduces the size of miscellaneous core
392 kernel data structures. This saves memory on small machines,
393 but may reduce performance.
394
395config FUTEX
396 bool "Enable futex support" if EMBEDDED
397 default y
23f78d4a 398 select RT_MUTEXES
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399 help
400 Disabling this option will cause the kernel to be built without
401 support for "fast userspace mutexes". The resulting kernel may not
402 run glibc-based applications correctly.
403
404config EPOLL
405 bool "Enable eventpoll support" if EMBEDDED
406 default y
407 help
408 Disabling this option will cause the kernel to be built without
409 support for epoll family of system calls.
410
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411config SHMEM
412 bool "Use full shmem filesystem" if EMBEDDED
413 default y
414 depends on MMU
415 help
416 The shmem is an internal filesystem used to manage shared memory.
417 It is backed by swap and manages resource limits. It is also exported
418 to userspace as tmpfs if TMPFS is enabled. Disabling this
419 option replaces shmem and tmpfs with the much simpler ramfs code,
420 which may be appropriate on small systems without swap.
421
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422config SLAB
423 default y
424 bool "Use full SLAB allocator" if EMBEDDED
425 help
426 Disabling this replaces the advanced SLAB allocator and
427 kmalloc support with the drastically simpler SLOB allocator.
428 SLOB is more space efficient but does not scale well and is
429 more susceptible to fragmentation.
430
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431config VM_EVENT_COUNTERS
432 default y
433 bool "Enable VM event counters for /proc/vmstat" if EMBEDDED
434 help
435 VM event counters are only needed to for event counts to be
436 shown. They have no function for the kernel itself. This
437 option allows the disabling of the VM event counters.
438 /proc/vmstat will only show page counts.
439
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440endmenu # General setup
441
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442config RT_MUTEXES
443 boolean
444 select PLIST
445
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446config TINY_SHMEM
447 default !SHMEM
448 bool
449
450config BASE_SMALL
451 int
452 default 0 if BASE_FULL
453 default 1 if !BASE_FULL
454
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455config SLOB
456 default !SLAB
457 bool
458
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459menu "Loadable module support"
460
461config MODULES
462 bool "Enable loadable module support"
463 help
464 Kernel modules are small pieces of compiled code which can
465 be inserted in the running kernel, rather than being
466 permanently built into the kernel. You use the "modprobe"
467 tool to add (and sometimes remove) them. If you say Y here,
468 many parts of the kernel can be built as modules (by
469 answering M instead of Y where indicated): this is most
470 useful for infrequently used options which are not required
471 for booting. For more information, see the man pages for
472 modprobe, lsmod, modinfo, insmod and rmmod.
473
474 If you say Y here, you will need to run "make
475 modules_install" to put the modules under /lib/modules/
476 where modprobe can find them (you may need to be root to do
477 this).
478
479 If unsure, say Y.
480
481config MODULE_UNLOAD
482 bool "Module unloading"
483 depends on MODULES
484 help
485 Without this option you will not be able to unload any
486 modules (note that some modules may not be unloadable
487 anyway), which makes your kernel slightly smaller and
488 simpler. If unsure, say Y.
489
490config MODULE_FORCE_UNLOAD
491 bool "Forced module unloading"
492 depends on MODULE_UNLOAD && EXPERIMENTAL
493 help
494 This option allows you to force a module to unload, even if the
495 kernel believes it is unsafe: the kernel will remove the module
496 without waiting for anyone to stop using it (using the -f option to
497 rmmod). This is mainly for kernel developers and desperate users.
498 If unsure, say N.
499
1da177e4 500config MODVERSIONS
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501 bool "Module versioning support"
502 depends on MODULES
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503 help
504 Usually, you have to use modules compiled with your kernel.
505 Saying Y here makes it sometimes possible to use modules
506 compiled for different kernels, by adding enough information
507 to the modules to (hopefully) spot any changes which would
508 make them incompatible with the kernel you are running. If
509 unsure, say N.
510
511config MODULE_SRCVERSION_ALL
512 bool "Source checksum for all modules"
513 depends on MODULES
514 help
515 Modules which contain a MODULE_VERSION get an extra "srcversion"
516 field inserted into their modinfo section, which contains a
517 sum of the source files which made it. This helps maintainers
518 see exactly which source was used to build a module (since
519 others sometimes change the module source without updating
520 the version). With this option, such a "srcversion" field
521 will be created for all modules. If unsure, say N.
522
523config KMOD
524 bool "Automatic kernel module loading"
525 depends on MODULES
526 help
527 Normally when you have selected some parts of the kernel to
528 be created as kernel modules, you must load them (using the
529 "modprobe" command) before you can use them. If you say Y
530 here, some parts of the kernel will be able to load modules
531 automatically: when a part of the kernel needs a module, it
532 runs modprobe with the appropriate arguments, thereby
533 loading the module if it is available. If unsure, say Y.
534
535config STOP_MACHINE
536 bool
537 default y
538 depends on (SMP && MODULE_UNLOAD) || HOTPLUG_CPU
539 help
540 Need stop_machine() primitive.
541endmenu
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542
543menu "Block layer"
544source "block/Kconfig"
545endmenu