Kconfig 36 KB

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  1. #
  2. # For a description of the syntax of this configuration file,
  3. # see Documentation/kbuild/kconfig-language.txt.
  4. #
  5. mainmenu "Linux Kernel Configuration"
  6. config X86_32
  7. bool
  8. default y
  9. help
  10. This is Linux's home port. Linux was originally native to the Intel
  11. 386, and runs on all the later x86 processors including the Intel
  12. 486, 586, Pentiums, and various instruction-set-compatible chips by
  13. AMD, Cyrix, and others.
  14. config SEMAPHORE_SLEEPERS
  15. bool
  16. default y
  17. config X86
  18. bool
  19. default y
  20. config MMU
  21. bool
  22. default y
  23. config SBUS
  24. bool
  25. config GENERIC_ISA_DMA
  26. bool
  27. default y
  28. config GENERIC_IOMAP
  29. bool
  30. default y
  31. config ARCH_MAY_HAVE_PC_FDC
  32. bool
  33. default y
  34. config DMI
  35. bool
  36. default y
  37. source "init/Kconfig"
  38. menu "Processor type and features"
  39. choice
  40. prompt "Subarchitecture Type"
  41. default X86_PC
  42. config X86_PC
  43. bool "PC-compatible"
  44. help
  45. Choose this option if your computer is a standard PC or compatible.
  46. config X86_ELAN
  47. bool "AMD Elan"
  48. help
  49. Select this for an AMD Elan processor.
  50. Do not use this option for K6/Athlon/Opteron processors!
  51. If unsure, choose "PC-compatible" instead.
  52. config X86_VOYAGER
  53. bool "Voyager (NCR)"
  54. help
  55. Voyager is an MCA-based 32-way capable SMP architecture proprietary
  56. to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
  57. *** WARNING ***
  58. If you do not specifically know you have a Voyager based machine,
  59. say N here, otherwise the kernel you build will not be bootable.
  60. config X86_NUMAQ
  61. bool "NUMAQ (IBM/Sequent)"
  62. select NUMA
  63. help
  64. This option is used for getting Linux to run on a (IBM/Sequent) NUMA
  65. multiquad box. This changes the way that processors are bootstrapped,
  66. and uses Clustered Logical APIC addressing mode instead of Flat Logical.
  67. You will need a new lynxer.elf file to flash your firmware with - send
  68. email to <Martin.Bligh@us.ibm.com>.
  69. config X86_SUMMIT
  70. bool "Summit/EXA (IBM x440)"
  71. depends on SMP
  72. help
  73. This option is needed for IBM systems that use the Summit/EXA chipset.
  74. In particular, it is needed for the x440.
  75. If you don't have one of these computers, you should say N here.
  76. config X86_BIGSMP
  77. bool "Support for other sub-arch SMP systems with more than 8 CPUs"
  78. depends on SMP
  79. help
  80. This option is needed for the systems that have more than 8 CPUs
  81. and if the system is not of any sub-arch type above.
  82. If you don't have such a system, you should say N here.
  83. config X86_VISWS
  84. bool "SGI 320/540 (Visual Workstation)"
  85. help
  86. The SGI Visual Workstation series is an IA32-based workstation
  87. based on SGI systems chips with some legacy PC hardware attached.
  88. Say Y here to create a kernel to run on the SGI 320 or 540.
  89. A kernel compiled for the Visual Workstation will not run on PCs
  90. and vice versa. See <file:Documentation/sgi-visws.txt> for details.
  91. config X86_GENERICARCH
  92. bool "Generic architecture (Summit, bigsmp, ES7000, default)"
  93. depends on SMP
  94. help
  95. This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
  96. It is intended for a generic binary kernel.
  97. config X86_ES7000
  98. bool "Support for Unisys ES7000 IA32 series"
  99. depends on SMP
  100. help
  101. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  102. supposed to run on an IA32-based Unisys ES7000 system.
  103. Only choose this option if you have such a system, otherwise you
  104. should say N here.
  105. endchoice
  106. config ACPI_SRAT
  107. bool
  108. default y
  109. depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
  110. config X86_SUMMIT_NUMA
  111. bool
  112. default y
  113. depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
  114. config X86_CYCLONE_TIMER
  115. bool
  116. default y
  117. depends on X86_SUMMIT || X86_GENERICARCH
  118. config ES7000_CLUSTERED_APIC
  119. bool
  120. default y
  121. depends on SMP && X86_ES7000 && MPENTIUMIII
  122. source "arch/i386/Kconfig.cpu"
  123. config HPET_TIMER
  124. bool "HPET Timer Support"
  125. help
  126. This enables the use of the HPET for the kernel's internal timer.
  127. HPET is the next generation timer replacing legacy 8254s.
  128. You can safely choose Y here. However, HPET will only be
  129. activated if the platform and the BIOS support this feature.
  130. Otherwise the 8254 will be used for timing services.
  131. Choose N to continue using the legacy 8254 timer.
  132. config HPET_EMULATE_RTC
  133. bool
  134. depends on HPET_TIMER && RTC=y
  135. default y
  136. config SMP
  137. bool "Symmetric multi-processing support"
  138. ---help---
  139. This enables support for systems with more than one CPU. If you have
  140. a system with only one CPU, like most personal computers, say N. If
  141. you have a system with more than one CPU, say Y.
  142. If you say N here, the kernel will run on single and multiprocessor
  143. machines, but will use only one CPU of a multiprocessor machine. If
  144. you say Y here, the kernel will run on many, but not all,
  145. singleprocessor machines. On a singleprocessor machine, the kernel
  146. will run faster if you say N here.
  147. Note that if you say Y here and choose architecture "586" or
  148. "Pentium" under "Processor family", the kernel will not work on 486
  149. architectures. Similarly, multiprocessor kernels for the "PPro"
  150. architecture may not work on all Pentium based boards.
  151. People using multiprocessor machines who say Y here should also say
  152. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  153. Management" code will be disabled if you say Y here.
  154. See also the <file:Documentation/smp.txt>,
  155. <file:Documentation/i386/IO-APIC.txt>,
  156. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  157. <http://www.tldp.org/docs.html#howto>.
  158. If you don't know what to do here, say N.
  159. config NR_CPUS
  160. int "Maximum number of CPUs (2-255)"
  161. range 2 255
  162. depends on SMP
  163. default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
  164. default "8"
  165. help
  166. This allows you to specify the maximum number of CPUs which this
  167. kernel will support. The maximum supported value is 255 and the
  168. minimum value which makes sense is 2.
  169. This is purely to save memory - each supported CPU adds
  170. approximately eight kilobytes to the kernel image.
  171. config SCHED_SMT
  172. bool "SMT (Hyperthreading) scheduler support"
  173. depends on SMP
  174. default off
  175. help
  176. SMT scheduler support improves the CPU scheduler's decision making
  177. when dealing with Intel Pentium 4 chips with HyperThreading at a
  178. cost of slightly increased overhead in some places. If unsure say
  179. N here.
  180. source "kernel/Kconfig.preempt"
  181. config X86_UP_APIC
  182. bool "Local APIC support on uniprocessors"
  183. depends on !SMP && !(X86_VISWS || X86_VOYAGER)
  184. help
  185. A local APIC (Advanced Programmable Interrupt Controller) is an
  186. integrated interrupt controller in the CPU. If you have a single-CPU
  187. system which has a processor with a local APIC, you can say Y here to
  188. enable and use it. If you say Y here even though your machine doesn't
  189. have a local APIC, then the kernel will still run with no slowdown at
  190. all. The local APIC supports CPU-generated self-interrupts (timer,
  191. performance counters), and the NMI watchdog which detects hard
  192. lockups.
  193. config X86_UP_IOAPIC
  194. bool "IO-APIC support on uniprocessors"
  195. depends on X86_UP_APIC
  196. help
  197. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  198. SMP-capable replacement for PC-style interrupt controllers. Most
  199. SMP systems and many recent uniprocessor systems have one.
  200. If you have a single-CPU system with an IO-APIC, you can say Y here
  201. to use it. If you say Y here even though your machine doesn't have
  202. an IO-APIC, then the kernel will still run with no slowdown at all.
  203. config X86_LOCAL_APIC
  204. bool
  205. depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
  206. default y
  207. config X86_IO_APIC
  208. bool
  209. depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
  210. default y
  211. config X86_VISWS_APIC
  212. bool
  213. depends on X86_VISWS
  214. default y
  215. config X86_MCE
  216. bool "Machine Check Exception"
  217. depends on !X86_VOYAGER
  218. ---help---
  219. Machine Check Exception support allows the processor to notify the
  220. kernel if it detects a problem (e.g. overheating, component failure).
  221. The action the kernel takes depends on the severity of the problem,
  222. ranging from a warning message on the console, to halting the machine.
  223. Your processor must be a Pentium or newer to support this - check the
  224. flags in /proc/cpuinfo for mce. Note that some older Pentium systems
  225. have a design flaw which leads to false MCE events - hence MCE is
  226. disabled on all P5 processors, unless explicitly enabled with "mce"
  227. as a boot argument. Similarly, if MCE is built in and creates a
  228. problem on some new non-standard machine, you can boot with "nomce"
  229. to disable it. MCE support simply ignores non-MCE processors like
  230. the 386 and 486, so nearly everyone can say Y here.
  231. config X86_MCE_NONFATAL
  232. tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
  233. depends on X86_MCE
  234. help
  235. Enabling this feature starts a timer that triggers every 5 seconds which
  236. will look at the machine check registers to see if anything happened.
  237. Non-fatal problems automatically get corrected (but still logged).
  238. Disable this if you don't want to see these messages.
  239. Seeing the messages this option prints out may be indicative of dying hardware,
  240. or out-of-spec (ie, overclocked) hardware.
  241. This option only does something on certain CPUs.
  242. (AMD Athlon/Duron and Intel Pentium 4)
  243. config X86_MCE_P4THERMAL
  244. bool "check for P4 thermal throttling interrupt."
  245. depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
  246. help
  247. Enabling this feature will cause a message to be printed when the P4
  248. enters thermal throttling.
  249. config TOSHIBA
  250. tristate "Toshiba Laptop support"
  251. ---help---
  252. This adds a driver to safely access the System Management Mode of
  253. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  254. not work on models with a Phoenix BIOS. The System Management Mode
  255. is used to set the BIOS and power saving options on Toshiba portables.
  256. For information on utilities to make use of this driver see the
  257. Toshiba Linux utilities web site at:
  258. <http://www.buzzard.org.uk/toshiba/>.
  259. Say Y if you intend to run this kernel on a Toshiba portable.
  260. Say N otherwise.
  261. config I8K
  262. tristate "Dell laptop support"
  263. ---help---
  264. This adds a driver to safely access the System Management Mode
  265. of the CPU on the Dell Inspiron 8000. The System Management Mode
  266. is used to read cpu temperature and cooling fan status and to
  267. control the fans on the I8K portables.
  268. This driver has been tested only on the Inspiron 8000 but it may
  269. also work with other Dell laptops. You can force loading on other
  270. models by passing the parameter `force=1' to the module. Use at
  271. your own risk.
  272. For information on utilities to make use of this driver see the
  273. I8K Linux utilities web site at:
  274. <http://people.debian.org/~dz/i8k/>
  275. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  276. Say N otherwise.
  277. config X86_REBOOTFIXUPS
  278. bool "Enable X86 board specific fixups for reboot"
  279. depends on X86
  280. default n
  281. ---help---
  282. This enables chipset and/or board specific fixups to be done
  283. in order to get reboot to work correctly. This is only needed on
  284. some combinations of hardware and BIOS. The symptom, for which
  285. this config is intended, is when reboot ends with a stalled/hung
  286. system.
  287. Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
  288. combination.
  289. Say Y if you want to enable the fixup. Currently, it's safe to
  290. enable this option even if you don't need it.
  291. Say N otherwise.
  292. config MICROCODE
  293. tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
  294. ---help---
  295. If you say Y here and also to "/dev file system support" in the
  296. 'File systems' section, you will be able to update the microcode on
  297. Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
  298. Pentium III, Pentium 4, Xeon etc. You will obviously need the
  299. actual microcode binary data itself which is not shipped with the
  300. Linux kernel.
  301. For latest news and information on obtaining all the required
  302. ingredients for this driver, check:
  303. <http://www.urbanmyth.org/microcode/>.
  304. To compile this driver as a module, choose M here: the
  305. module will be called microcode.
  306. config X86_MSR
  307. tristate "/dev/cpu/*/msr - Model-specific register support"
  308. help
  309. This device gives privileged processes access to the x86
  310. Model-Specific Registers (MSRs). It is a character device with
  311. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  312. MSR accesses are directed to a specific CPU on multi-processor
  313. systems.
  314. config X86_CPUID
  315. tristate "/dev/cpu/*/cpuid - CPU information support"
  316. help
  317. This device gives processes access to the x86 CPUID instruction to
  318. be executed on a specific processor. It is a character device
  319. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  320. /dev/cpu/31/cpuid.
  321. source "drivers/firmware/Kconfig"
  322. choice
  323. prompt "High Memory Support"
  324. default NOHIGHMEM
  325. config NOHIGHMEM
  326. bool "off"
  327. ---help---
  328. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  329. However, the address space of 32-bit x86 processors is only 4
  330. Gigabytes large. That means that, if you have a large amount of
  331. physical memory, not all of it can be "permanently mapped" by the
  332. kernel. The physical memory that's not permanently mapped is called
  333. "high memory".
  334. If you are compiling a kernel which will never run on a machine with
  335. more than 1 Gigabyte total physical RAM, answer "off" here (default
  336. choice and suitable for most users). This will result in a "3GB/1GB"
  337. split: 3GB are mapped so that each process sees a 3GB virtual memory
  338. space and the remaining part of the 4GB virtual memory space is used
  339. by the kernel to permanently map as much physical memory as
  340. possible.
  341. If the machine has between 1 and 4 Gigabytes physical RAM, then
  342. answer "4GB" here.
  343. If more than 4 Gigabytes is used then answer "64GB" here. This
  344. selection turns Intel PAE (Physical Address Extension) mode on.
  345. PAE implements 3-level paging on IA32 processors. PAE is fully
  346. supported by Linux, PAE mode is implemented on all recent Intel
  347. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  348. then the kernel will not boot on CPUs that don't support PAE!
  349. The actual amount of total physical memory will either be
  350. auto detected or can be forced by using a kernel command line option
  351. such as "mem=256M". (Try "man bootparam" or see the documentation of
  352. your boot loader (lilo or loadlin) about how to pass options to the
  353. kernel at boot time.)
  354. If unsure, say "off".
  355. config HIGHMEM4G
  356. bool "4GB"
  357. help
  358. Select this if you have a 32-bit processor and between 1 and 4
  359. gigabytes of physical RAM.
  360. config HIGHMEM64G
  361. bool "64GB"
  362. help
  363. Select this if you have a 32-bit processor and more than 4
  364. gigabytes of physical RAM.
  365. endchoice
  366. choice
  367. depends on EXPERIMENTAL && !X86_PAE
  368. prompt "Memory split"
  369. default VMSPLIT_3G
  370. help
  371. Select the desired split between kernel and user memory.
  372. If the address range available to the kernel is less than the
  373. physical memory installed, the remaining memory will be available
  374. as "high memory". Accessing high memory is a little more costly
  375. than low memory, as it needs to be mapped into the kernel first.
  376. Note that increasing the kernel address space limits the range
  377. available to user programs, making the address space there
  378. tighter. Selecting anything other than the default 3G/1G split
  379. will also likely make your kernel incompatible with binary-only
  380. kernel modules.
  381. If you are not absolutely sure what you are doing, leave this
  382. option alone!
  383. config VMSPLIT_3G
  384. bool "3G/1G user/kernel split"
  385. config VMSPLIT_3G_OPT
  386. bool "3G/1G user/kernel split (for full 1G low memory)"
  387. config VMSPLIT_2G
  388. bool "2G/2G user/kernel split"
  389. config VMSPLIT_1G
  390. bool "1G/3G user/kernel split"
  391. endchoice
  392. config PAGE_OFFSET
  393. hex
  394. default 0xB0000000 if VMSPLIT_3G_OPT
  395. default 0x78000000 if VMSPLIT_2G
  396. default 0x40000000 if VMSPLIT_1G
  397. default 0xC0000000
  398. config HIGHMEM
  399. bool
  400. depends on HIGHMEM64G || HIGHMEM4G
  401. default y
  402. config X86_PAE
  403. bool
  404. depends on HIGHMEM64G
  405. default y
  406. # Common NUMA Features
  407. config NUMA
  408. bool "Numa Memory Allocation and Scheduler Support"
  409. depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
  410. default n if X86_PC
  411. default y if (X86_NUMAQ || X86_SUMMIT)
  412. # Need comments to help the hapless user trying to turn on NUMA support
  413. comment "NUMA (NUMA-Q) requires SMP, 64GB highmem support"
  414. depends on X86_NUMAQ && (!HIGHMEM64G || !SMP)
  415. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  416. depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  417. config HAVE_ARCH_BOOTMEM_NODE
  418. bool
  419. depends on NUMA
  420. default y
  421. config ARCH_HAVE_MEMORY_PRESENT
  422. bool
  423. depends on DISCONTIGMEM
  424. default y
  425. config NEED_NODE_MEMMAP_SIZE
  426. bool
  427. depends on DISCONTIGMEM || SPARSEMEM
  428. default y
  429. config HAVE_ARCH_ALLOC_REMAP
  430. bool
  431. depends on NUMA
  432. default y
  433. config ARCH_FLATMEM_ENABLE
  434. def_bool y
  435. depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
  436. config ARCH_DISCONTIGMEM_ENABLE
  437. def_bool y
  438. depends on NUMA
  439. config ARCH_DISCONTIGMEM_DEFAULT
  440. def_bool y
  441. depends on NUMA
  442. config ARCH_SPARSEMEM_ENABLE
  443. def_bool y
  444. depends on (NUMA || (X86_PC && EXPERIMENTAL))
  445. select SPARSEMEM_STATIC
  446. config ARCH_SELECT_MEMORY_MODEL
  447. def_bool y
  448. depends on ARCH_SPARSEMEM_ENABLE
  449. source "mm/Kconfig"
  450. config HAVE_ARCH_EARLY_PFN_TO_NID
  451. bool
  452. default y
  453. depends on NUMA
  454. config HIGHPTE
  455. bool "Allocate 3rd-level pagetables from highmem"
  456. depends on HIGHMEM4G || HIGHMEM64G
  457. help
  458. The VM uses one page table entry for each page of physical memory.
  459. For systems with a lot of RAM, this can be wasteful of precious
  460. low memory. Setting this option will put user-space page table
  461. entries in high memory.
  462. config MATH_EMULATION
  463. bool "Math emulation"
  464. ---help---
  465. Linux can emulate a math coprocessor (used for floating point
  466. operations) if you don't have one. 486DX and Pentium processors have
  467. a math coprocessor built in, 486SX and 386 do not, unless you added
  468. a 487DX or 387, respectively. (The messages during boot time can
  469. give you some hints here ["man dmesg"].) Everyone needs either a
  470. coprocessor or this emulation.
  471. If you don't have a math coprocessor, you need to say Y here; if you
  472. say Y here even though you have a coprocessor, the coprocessor will
  473. be used nevertheless. (This behavior can be changed with the kernel
  474. command line option "no387", which comes handy if your coprocessor
  475. is broken. Try "man bootparam" or see the documentation of your boot
  476. loader (lilo or loadlin) about how to pass options to the kernel at
  477. boot time.) This means that it is a good idea to say Y here if you
  478. intend to use this kernel on different machines.
  479. More information about the internals of the Linux math coprocessor
  480. emulation can be found in <file:arch/i386/math-emu/README>.
  481. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  482. kernel, it won't hurt.
  483. config MTRR
  484. bool "MTRR (Memory Type Range Register) support"
  485. ---help---
  486. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  487. the Memory Type Range Registers (MTRRs) may be used to control
  488. processor access to memory ranges. This is most useful if you have
  489. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  490. allows bus write transfers to be combined into a larger transfer
  491. before bursting over the PCI/AGP bus. This can increase performance
  492. of image write operations 2.5 times or more. Saying Y here creates a
  493. /proc/mtrr file which may be used to manipulate your processor's
  494. MTRRs. Typically the X server should use this.
  495. This code has a reasonably generic interface so that similar
  496. control registers on other processors can be easily supported
  497. as well:
  498. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  499. Registers (ARRs) which provide a similar functionality to MTRRs. For
  500. these, the ARRs are used to emulate the MTRRs.
  501. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  502. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  503. write-combining. All of these processors are supported by this code
  504. and it makes sense to say Y here if you have one of them.
  505. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  506. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  507. can lead to all sorts of problems, so it's good to say Y here.
  508. You can safely say Y even if your machine doesn't have MTRRs, you'll
  509. just add about 9 KB to your kernel.
  510. See <file:Documentation/mtrr.txt> for more information.
  511. config EFI
  512. bool "Boot from EFI support (EXPERIMENTAL)"
  513. depends on ACPI
  514. default n
  515. ---help---
  516. This enables the the kernel to boot on EFI platforms using
  517. system configuration information passed to it from the firmware.
  518. This also enables the kernel to use any EFI runtime services that are
  519. available (such as the EFI variable services).
  520. This option is only useful on systems that have EFI firmware
  521. and will result in a kernel image that is ~8k larger. In addition,
  522. you must use the latest ELILO loader available at
  523. <http://elilo.sourceforge.net> in order to take advantage of
  524. kernel initialization using EFI information (neither GRUB nor LILO know
  525. anything about EFI). However, even with this option, the resultant
  526. kernel should continue to boot on existing non-EFI platforms.
  527. config IRQBALANCE
  528. bool "Enable kernel irq balancing"
  529. depends on SMP && X86_IO_APIC
  530. default y
  531. help
  532. The default yes will allow the kernel to do irq load balancing.
  533. Saying no will keep the kernel from doing irq load balancing.
  534. # turning this on wastes a bunch of space.
  535. # Summit needs it only when NUMA is on
  536. config BOOT_IOREMAP
  537. bool
  538. depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
  539. default y
  540. config REGPARM
  541. bool "Use register arguments (EXPERIMENTAL)"
  542. depends on EXPERIMENTAL
  543. default n
  544. help
  545. Compile the kernel with -mregparm=3. This uses a different ABI
  546. and passes the first three arguments of a function call in registers.
  547. This will probably break binary only modules.
  548. config SECCOMP
  549. bool "Enable seccomp to safely compute untrusted bytecode"
  550. depends on PROC_FS
  551. default y
  552. help
  553. This kernel feature is useful for number crunching applications
  554. that may need to compute untrusted bytecode during their
  555. execution. By using pipes or other transports made available to
  556. the process as file descriptors supporting the read/write
  557. syscalls, it's possible to isolate those applications in
  558. their own address space using seccomp. Once seccomp is
  559. enabled via /proc/<pid>/seccomp, it cannot be disabled
  560. and the task is only allowed to execute a few safe syscalls
  561. defined by each seccomp mode.
  562. If unsure, say Y. Only embedded should say N here.
  563. source kernel/Kconfig.hz
  564. config KEXEC
  565. bool "kexec system call (EXPERIMENTAL)"
  566. depends on EXPERIMENTAL
  567. help
  568. kexec is a system call that implements the ability to shutdown your
  569. current kernel, and to start another kernel. It is like a reboot
  570. but it is indepedent of the system firmware. And like a reboot
  571. you can start any kernel with it, not just Linux.
  572. The name comes from the similiarity to the exec system call.
  573. It is an ongoing process to be certain the hardware in a machine
  574. is properly shutdown, so do not be surprised if this code does not
  575. initially work for you. It may help to enable device hotplugging
  576. support. As of this writing the exact hardware interface is
  577. strongly in flux, so no good recommendation can be made.
  578. config CRASH_DUMP
  579. bool "kernel crash dumps (EXPERIMENTAL)"
  580. depends on EXPERIMENTAL
  581. depends on HIGHMEM
  582. help
  583. Generate crash dump after being started by kexec.
  584. config PHYSICAL_START
  585. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  586. default "0x1000000" if CRASH_DUMP
  587. default "0x100000"
  588. help
  589. This gives the physical address where the kernel is loaded. Normally
  590. for regular kernels this value is 0x100000 (1MB). But in the case
  591. of kexec on panic the fail safe kernel needs to run at a different
  592. address than the panic-ed kernel. This option is used to set the load
  593. address for kernels used to capture crash dump on being kexec'ed
  594. after panic. The default value for crash dump kernels is
  595. 0x1000000 (16MB). This can also be set based on the "X" value as
  596. specified in the "crashkernel=YM@XM" command line boot parameter
  597. passed to the panic-ed kernel. Typically this parameter is set as
  598. crashkernel=64M@16M. Please take a look at
  599. Documentation/kdump/kdump.txt for more details about crash dumps.
  600. Don't change this unless you know what you are doing.
  601. config HOTPLUG_CPU
  602. bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
  603. depends on SMP && HOTPLUG && EXPERIMENTAL
  604. ---help---
  605. Say Y here to experiment with turning CPUs off and on. CPUs
  606. can be controlled through /sys/devices/system/cpu.
  607. Say N.
  608. config DOUBLEFAULT
  609. default y
  610. bool "Enable doublefault exception handler" if EMBEDDED
  611. help
  612. This option allows trapping of rare doublefault exceptions that
  613. would otherwise cause a system to silently reboot. Disabling this
  614. option saves about 4k and might cause you much additional grey
  615. hair.
  616. endmenu
  617. menu "Power management options (ACPI, APM)"
  618. depends on !X86_VOYAGER
  619. source kernel/power/Kconfig
  620. source "drivers/acpi/Kconfig"
  621. menu "APM (Advanced Power Management) BIOS Support"
  622. depends on PM && !X86_VISWS
  623. config APM
  624. tristate "APM (Advanced Power Management) BIOS support"
  625. depends on PM
  626. ---help---
  627. APM is a BIOS specification for saving power using several different
  628. techniques. This is mostly useful for battery powered laptops with
  629. APM compliant BIOSes. If you say Y here, the system time will be
  630. reset after a RESUME operation, the /proc/apm device will provide
  631. battery status information, and user-space programs will receive
  632. notification of APM "events" (e.g. battery status change).
  633. If you select "Y" here, you can disable actual use of the APM
  634. BIOS by passing the "apm=off" option to the kernel at boot time.
  635. Note that the APM support is almost completely disabled for
  636. machines with more than one CPU.
  637. In order to use APM, you will need supporting software. For location
  638. and more information, read <file:Documentation/pm.txt> and the
  639. Battery Powered Linux mini-HOWTO, available from
  640. <http://www.tldp.org/docs.html#howto>.
  641. This driver does not spin down disk drives (see the hdparm(8)
  642. manpage ("man 8 hdparm") for that), and it doesn't turn off
  643. VESA-compliant "green" monitors.
  644. This driver does not support the TI 4000M TravelMate and the ACER
  645. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  646. desktop machines also don't have compliant BIOSes, and this driver
  647. may cause those machines to panic during the boot phase.
  648. Generally, if you don't have a battery in your machine, there isn't
  649. much point in using this driver and you should say N. If you get
  650. random kernel OOPSes or reboots that don't seem to be related to
  651. anything, try disabling/enabling this option (or disabling/enabling
  652. APM in your BIOS).
  653. Some other things you should try when experiencing seemingly random,
  654. "weird" problems:
  655. 1) make sure that you have enough swap space and that it is
  656. enabled.
  657. 2) pass the "no-hlt" option to the kernel
  658. 3) switch on floating point emulation in the kernel and pass
  659. the "no387" option to the kernel
  660. 4) pass the "floppy=nodma" option to the kernel
  661. 5) pass the "mem=4M" option to the kernel (thereby disabling
  662. all but the first 4 MB of RAM)
  663. 6) make sure that the CPU is not over clocked.
  664. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  665. 8) disable the cache from your BIOS settings
  666. 9) install a fan for the video card or exchange video RAM
  667. 10) install a better fan for the CPU
  668. 11) exchange RAM chips
  669. 12) exchange the motherboard.
  670. To compile this driver as a module, choose M here: the
  671. module will be called apm.
  672. config APM_IGNORE_USER_SUSPEND
  673. bool "Ignore USER SUSPEND"
  674. depends on APM
  675. help
  676. This option will ignore USER SUSPEND requests. On machines with a
  677. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  678. series notebooks, it is necessary to say Y because of a BIOS bug.
  679. config APM_DO_ENABLE
  680. bool "Enable PM at boot time"
  681. depends on APM
  682. ---help---
  683. Enable APM features at boot time. From page 36 of the APM BIOS
  684. specification: "When disabled, the APM BIOS does not automatically
  685. power manage devices, enter the Standby State, enter the Suspend
  686. State, or take power saving steps in response to CPU Idle calls."
  687. This driver will make CPU Idle calls when Linux is idle (unless this
  688. feature is turned off -- see "Do CPU IDLE calls", below). This
  689. should always save battery power, but more complicated APM features
  690. will be dependent on your BIOS implementation. You may need to turn
  691. this option off if your computer hangs at boot time when using APM
  692. support, or if it beeps continuously instead of suspending. Turn
  693. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  694. T400CDT. This is off by default since most machines do fine without
  695. this feature.
  696. config APM_CPU_IDLE
  697. bool "Make CPU Idle calls when idle"
  698. depends on APM
  699. help
  700. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  701. On some machines, this can activate improved power savings, such as
  702. a slowed CPU clock rate, when the machine is idle. These idle calls
  703. are made after the idle loop has run for some length of time (e.g.,
  704. 333 mS). On some machines, this will cause a hang at boot time or
  705. whenever the CPU becomes idle. (On machines with more than one CPU,
  706. this option does nothing.)
  707. config APM_DISPLAY_BLANK
  708. bool "Enable console blanking using APM"
  709. depends on APM
  710. help
  711. Enable console blanking using the APM. Some laptops can use this to
  712. turn off the LCD backlight when the screen blanker of the Linux
  713. virtual console blanks the screen. Note that this is only used by
  714. the virtual console screen blanker, and won't turn off the backlight
  715. when using the X Window system. This also doesn't have anything to
  716. do with your VESA-compliant power-saving monitor. Further, this
  717. option doesn't work for all laptops -- it might not turn off your
  718. backlight at all, or it might print a lot of errors to the console,
  719. especially if you are using gpm.
  720. config APM_RTC_IS_GMT
  721. bool "RTC stores time in GMT"
  722. depends on APM
  723. help
  724. Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
  725. stores the time in GMT (Greenwich Mean Time). Say N if your RTC
  726. stores localtime.
  727. It is in fact recommended to store GMT in your RTC, because then you
  728. don't have to worry about daylight savings time changes. The only
  729. reason not to use GMT in your RTC is if you also run a broken OS
  730. that doesn't understand GMT.
  731. config APM_ALLOW_INTS
  732. bool "Allow interrupts during APM BIOS calls"
  733. depends on APM
  734. help
  735. Normally we disable external interrupts while we are making calls to
  736. the APM BIOS as a measure to lessen the effects of a badly behaving
  737. BIOS implementation. The BIOS should reenable interrupts if it
  738. needs to. Unfortunately, some BIOSes do not -- especially those in
  739. many of the newer IBM Thinkpads. If you experience hangs when you
  740. suspend, try setting this to Y. Otherwise, say N.
  741. config APM_REAL_MODE_POWER_OFF
  742. bool "Use real mode APM BIOS call to power off"
  743. depends on APM
  744. help
  745. Use real mode APM BIOS calls to switch off the computer. This is
  746. a work-around for a number of buggy BIOSes. Switch this option on if
  747. your computer crashes instead of powering off properly.
  748. endmenu
  749. source "arch/i386/kernel/cpu/cpufreq/Kconfig"
  750. endmenu
  751. menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
  752. config PCI
  753. bool "PCI support" if !X86_VISWS
  754. depends on !X86_VOYAGER
  755. default y if X86_VISWS
  756. help
  757. Find out whether you have a PCI motherboard. PCI is the name of a
  758. bus system, i.e. the way the CPU talks to the other stuff inside
  759. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  760. VESA. If you have PCI, say Y, otherwise N.
  761. The PCI-HOWTO, available from
  762. <http://www.tldp.org/docs.html#howto>, contains valuable
  763. information about which PCI hardware does work under Linux and which
  764. doesn't.
  765. choice
  766. prompt "PCI access mode"
  767. depends on PCI && !X86_VISWS
  768. default PCI_GOANY
  769. ---help---
  770. On PCI systems, the BIOS can be used to detect the PCI devices and
  771. determine their configuration. However, some old PCI motherboards
  772. have BIOS bugs and may crash if this is done. Also, some embedded
  773. PCI-based systems don't have any BIOS at all. Linux can also try to
  774. detect the PCI hardware directly without using the BIOS.
  775. With this option, you can specify how Linux should detect the
  776. PCI devices. If you choose "BIOS", the BIOS will be used,
  777. if you choose "Direct", the BIOS won't be used, and if you
  778. choose "MMConfig", then PCI Express MMCONFIG will be used.
  779. If you choose "Any", the kernel will try MMCONFIG, then the
  780. direct access method and falls back to the BIOS if that doesn't
  781. work. If unsure, go with the default, which is "Any".
  782. config PCI_GOBIOS
  783. bool "BIOS"
  784. config PCI_GOMMCONFIG
  785. bool "MMConfig"
  786. config PCI_GODIRECT
  787. bool "Direct"
  788. config PCI_GOANY
  789. bool "Any"
  790. endchoice
  791. config PCI_BIOS
  792. bool
  793. depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
  794. default y
  795. config PCI_DIRECT
  796. bool
  797. depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
  798. default y
  799. config PCI_MMCONFIG
  800. bool
  801. depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
  802. default y
  803. source "drivers/pci/pcie/Kconfig"
  804. source "drivers/pci/Kconfig"
  805. config ISA_DMA_API
  806. bool
  807. default y
  808. config ISA
  809. bool "ISA support"
  810. depends on !(X86_VOYAGER || X86_VISWS)
  811. help
  812. Find out whether you have ISA slots on your motherboard. ISA is the
  813. name of a bus system, i.e. the way the CPU talks to the other stuff
  814. inside your box. Other bus systems are PCI, EISA, MicroChannel
  815. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  816. newer boards don't support it. If you have ISA, say Y, otherwise N.
  817. config EISA
  818. bool "EISA support"
  819. depends on ISA
  820. ---help---
  821. The Extended Industry Standard Architecture (EISA) bus was
  822. developed as an open alternative to the IBM MicroChannel bus.
  823. The EISA bus provided some of the features of the IBM MicroChannel
  824. bus while maintaining backward compatibility with cards made for
  825. the older ISA bus. The EISA bus saw limited use between 1988 and
  826. 1995 when it was made obsolete by the PCI bus.
  827. Say Y here if you are building a kernel for an EISA-based machine.
  828. Otherwise, say N.
  829. source "drivers/eisa/Kconfig"
  830. config MCA
  831. bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
  832. default y if X86_VOYAGER
  833. help
  834. MicroChannel Architecture is found in some IBM PS/2 machines and
  835. laptops. It is a bus system similar to PCI or ISA. See
  836. <file:Documentation/mca.txt> (and especially the web page given
  837. there) before attempting to build an MCA bus kernel.
  838. source "drivers/mca/Kconfig"
  839. config SCx200
  840. tristate "NatSemi SCx200 support"
  841. depends on !X86_VOYAGER
  842. help
  843. This provides basic support for the National Semiconductor SCx200
  844. processor. Right now this is just a driver for the GPIO pins.
  845. If you don't know what to do here, say N.
  846. This support is also available as a module. If compiled as a
  847. module, it will be called scx200.
  848. source "drivers/pcmcia/Kconfig"
  849. source "drivers/pci/hotplug/Kconfig"
  850. endmenu
  851. menu "Executable file formats"
  852. source "fs/Kconfig.binfmt"
  853. endmenu
  854. source "net/Kconfig"
  855. source "drivers/Kconfig"
  856. source "fs/Kconfig"
  857. menu "Instrumentation Support"
  858. depends on EXPERIMENTAL
  859. source "arch/i386/oprofile/Kconfig"
  860. config KPROBES
  861. bool "Kprobes (EXPERIMENTAL)"
  862. help
  863. Kprobes allows you to trap at almost any kernel address and
  864. execute a callback function. register_kprobe() establishes
  865. a probepoint and specifies the callback. Kprobes is useful
  866. for kernel debugging, non-intrusive instrumentation and testing.
  867. If in doubt, say "N".
  868. endmenu
  869. source "arch/i386/Kconfig.debug"
  870. source "security/Kconfig"
  871. source "crypto/Kconfig"
  872. source "lib/Kconfig"
  873. #
  874. # Use the generic interrupt handling code in kernel/irq/:
  875. #
  876. config GENERIC_HARDIRQS
  877. bool
  878. default y
  879. config GENERIC_IRQ_PROBE
  880. bool
  881. default y
  882. config GENERIC_PENDING_IRQ
  883. bool
  884. depends on GENERIC_HARDIRQS && SMP
  885. default y
  886. config X86_SMP
  887. bool
  888. depends on SMP && !X86_VOYAGER
  889. default y
  890. config X86_HT
  891. bool
  892. depends on SMP && !(X86_VISWS || X86_VOYAGER)
  893. default y
  894. config X86_BIOS_REBOOT
  895. bool
  896. depends on !(X86_VISWS || X86_VOYAGER)
  897. default y
  898. config X86_TRAMPOLINE
  899. bool
  900. depends on X86_SMP || (X86_VOYAGER && SMP)
  901. default y
  902. config KTIME_SCALAR
  903. bool
  904. default y