| blob | 5b5c6ea1a76cd0a818c0dfa3bcc0a1fb7df0a30c |
1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH != "i386"
5 ---help---
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
9 config X86_32
10 def_bool y
11 depends on !64BIT
12 select CLKSRC_I8253
13 select HAVE_UID16
15 config X86_64
16 def_bool y
17 depends on 64BIT
18 select X86_DEV_DMA_OPS
19 select ARCH_USE_CMPXCHG_LOCKREF
21 ### Arch settings
22 config X86
23 def_bool y
24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
25 select HAVE_AOUT if X86_32
26 select HAVE_UNSTABLE_SCHED_CLOCK
27 select ARCH_SUPPORTS_NUMA_BALANCING
28 select ARCH_WANTS_PROT_NUMA_PROT_NONE
29 select HAVE_IDE
30 select HAVE_OPROFILE
31 select HAVE_PCSPKR_PLATFORM
32 select HAVE_PERF_EVENTS
33 select HAVE_IOREMAP_PROT
34 select HAVE_KPROBES
35 select HAVE_MEMBLOCK
36 select HAVE_MEMBLOCK_NODE_MAP
37 select ARCH_DISCARD_MEMBLOCK
38 select ARCH_WANT_OPTIONAL_GPIOLIB
39 select ARCH_WANT_FRAME_POINTERS
40 select HAVE_DMA_ATTRS
41 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
42 select HAVE_KRETPROBES
43 select HAVE_OPTPROBES
44 select HAVE_KPROBES_ON_FTRACE
45 select HAVE_FTRACE_MCOUNT_RECORD
46 select HAVE_FENTRY if X86_64
47 select HAVE_C_RECORDMCOUNT
48 select HAVE_DYNAMIC_FTRACE
49 select HAVE_DYNAMIC_FTRACE_WITH_REGS
50 select HAVE_FUNCTION_TRACER
51 select HAVE_FUNCTION_GRAPH_TRACER
52 select HAVE_FUNCTION_GRAPH_FP_TEST
53 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
54 select HAVE_SYSCALL_TRACEPOINTS
55 select SYSCTL_EXCEPTION_TRACE
56 select HAVE_KVM
57 select HAVE_ARCH_KGDB
58 select HAVE_ARCH_TRACEHOOK
59 select HAVE_GENERIC_DMA_COHERENT if X86_32
60 select HAVE_EFFICIENT_UNALIGNED_ACCESS
61 select USER_STACKTRACE_SUPPORT
62 select HAVE_REGS_AND_STACK_ACCESS_API
63 select HAVE_DMA_API_DEBUG
64 select HAVE_KERNEL_GZIP
65 select HAVE_KERNEL_BZIP2
66 select HAVE_KERNEL_LZMA
67 select HAVE_KERNEL_XZ
68 select HAVE_KERNEL_LZO
69 select HAVE_KERNEL_LZ4
70 select HAVE_HW_BREAKPOINT
71 select HAVE_MIXED_BREAKPOINTS_REGS
72 select PERF_EVENTS
73 select HAVE_PERF_EVENTS_NMI
74 select HAVE_PERF_REGS
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_DEBUG_KMEMLEAK
77 select ANON_INODES
78 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
79 select HAVE_CMPXCHG_LOCAL
80 select HAVE_CMPXCHG_DOUBLE
81 select HAVE_ARCH_KMEMCHECK
82 select HAVE_USER_RETURN_NOTIFIER
83 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
84 select HAVE_ARCH_JUMP_LABEL
85 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
86 select SPARSE_IRQ
87 select GENERIC_FIND_FIRST_BIT
88 select GENERIC_IRQ_PROBE
89 select GENERIC_PENDING_IRQ if SMP
90 select GENERIC_IRQ_SHOW
91 select GENERIC_CLOCKEVENTS_MIN_ADJUST
92 select IRQ_FORCED_THREADING
93 select USE_GENERIC_SMP_HELPERS if SMP
94 select HAVE_BPF_JIT if X86_64
95 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
96 select CLKEVT_I8253
97 select ARCH_HAVE_NMI_SAFE_CMPXCHG
98 select GENERIC_IOMAP
99 select DCACHE_WORD_ACCESS
100 select GENERIC_SMP_IDLE_THREAD
101 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
102 select HAVE_ARCH_SECCOMP_FILTER
103 select BUILDTIME_EXTABLE_SORT
104 select GENERIC_CMOS_UPDATE
105 select HAVE_ARCH_SOFT_DIRTY
106 select CLOCKSOURCE_WATCHDOG
107 select GENERIC_CLOCKEVENTS
108 select ARCH_CLOCKSOURCE_DATA if X86_64
109 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
110 select GENERIC_TIME_VSYSCALL if X86_64
111 select KTIME_SCALAR if X86_32
112 select GENERIC_STRNCPY_FROM_USER
113 select GENERIC_STRNLEN_USER
114 select HAVE_CONTEXT_TRACKING if X86_64
115 select HAVE_IRQ_TIME_ACCOUNTING
116 select VIRT_TO_BUS
117 select MODULES_USE_ELF_REL if X86_32
118 select MODULES_USE_ELF_RELA if X86_64
119 select CLONE_BACKWARDS if X86_32
120 select ARCH_USE_BUILTIN_BSWAP
121 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
122 select OLD_SIGACTION if X86_32
123 select COMPAT_OLD_SIGACTION if IA32_EMULATION
124 select RTC_LIB
125 select HAVE_DEBUG_STACKOVERFLOW
126 select ARCH_SUPPORTS_ATOMIC_RMW
128 config INSTRUCTION_DECODER
129 def_bool y
130 depends on KPROBES || PERF_EVENTS || UPROBES
132 config OUTPUT_FORMAT
133 string
134 default "elf32-i386" if X86_32
135 default "elf64-x86-64" if X86_64
137 config ARCH_DEFCONFIG
138 string
139 default "arch/x86/configs/i386_defconfig" if X86_32
140 default "arch/x86/configs/x86_64_defconfig" if X86_64
142 config LOCKDEP_SUPPORT
143 def_bool y
145 config STACKTRACE_SUPPORT
146 def_bool y
148 config HAVE_LATENCYTOP_SUPPORT
149 def_bool y
151 config MMU
152 def_bool y
154 config SBUS
155 bool
157 config NEED_DMA_MAP_STATE
158 def_bool y
159 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
161 config NEED_SG_DMA_LENGTH
162 def_bool y
164 config GENERIC_ISA_DMA
165 def_bool y
166 depends on ISA_DMA_API
168 config GENERIC_BUG
169 def_bool y
170 depends on BUG
171 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
173 config GENERIC_BUG_RELATIVE_POINTERS
174 bool
176 config GENERIC_HWEIGHT
177 def_bool y
179 config ARCH_MAY_HAVE_PC_FDC
180 def_bool y
181 depends on ISA_DMA_API
183 config RWSEM_XCHGADD_ALGORITHM
184 def_bool y
186 config GENERIC_CALIBRATE_DELAY
187 def_bool y
189 config ARCH_HAS_CPU_RELAX
190 def_bool y
192 config ARCH_HAS_CACHE_LINE_SIZE
193 def_bool y
195 config ARCH_HAS_CPU_AUTOPROBE
196 def_bool y
198 config HAVE_SETUP_PER_CPU_AREA
199 def_bool y
201 config NEED_PER_CPU_EMBED_FIRST_CHUNK
202 def_bool y
204 config NEED_PER_CPU_PAGE_FIRST_CHUNK
205 def_bool y
207 config ARCH_HIBERNATION_POSSIBLE
208 def_bool y
210 config ARCH_SUSPEND_POSSIBLE
211 def_bool y
213 config ARCH_WANT_HUGE_PMD_SHARE
214 def_bool y
216 config ARCH_WANT_GENERAL_HUGETLB
217 def_bool y
219 config ZONE_DMA32
220 bool
221 default X86_64
223 config AUDIT_ARCH
224 bool
225 default X86_64
227 config ARCH_SUPPORTS_OPTIMIZED_INLINING
228 def_bool y
230 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
231 def_bool y
233 config HAVE_INTEL_TXT
234 def_bool y
235 depends on INTEL_IOMMU && ACPI
237 config X86_32_SMP
238 def_bool y
239 depends on X86_32 && SMP
241 config X86_64_SMP
242 def_bool y
243 depends on X86_64 && SMP
245 config X86_HT
246 def_bool y
247 depends on SMP
249 config X86_32_LAZY_GS
250 def_bool y
251 depends on X86_32 && !CC_STACKPROTECTOR
253 config ARCH_HWEIGHT_CFLAGS
254 string
255 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
256 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
258 config ARCH_CPU_PROBE_RELEASE
259 def_bool y
260 depends on HOTPLUG_CPU
262 config ARCH_SUPPORTS_UPROBES
263 def_bool y
265 source "init/Kconfig"
266 source "kernel/Kconfig.freezer"
268 menu "Processor type and features"
270 config ZONE_DMA
271 bool "DMA memory allocation support" if EXPERT
272 default y
273 help
274 DMA memory allocation support allows devices with less than 32-bit
275 addressing to allocate within the first 16MB of address space.
276 Disable if no such devices will be used.
278 If unsure, say Y.
280 config SMP
281 bool "Symmetric multi-processing support"
282 ---help---
283 This enables support for systems with more than one CPU. If you have
284 a system with only one CPU, like most personal computers, say N. If
285 you have a system with more than one CPU, say Y.
287 If you say N here, the kernel will run on single and multiprocessor
288 machines, but will use only one CPU of a multiprocessor machine. If
289 you say Y here, the kernel will run on many, but not all,
290 singleprocessor machines. On a singleprocessor machine, the kernel
291 will run faster if you say N here.
293 Note that if you say Y here and choose architecture "586" or
294 "Pentium" under "Processor family", the kernel will not work on 486
295 architectures. Similarly, multiprocessor kernels for the "PPro"
296 architecture may not work on all Pentium based boards.
298 People using multiprocessor machines who say Y here should also say
299 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
300 Management" code will be disabled if you say Y here.
302 See also <file:Documentation/x86/i386/IO-APIC.txt>,
303 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
304 <http://www.tldp.org/docs.html#howto>.
306 If you don't know what to do here, say N.
308 config X86_X2APIC
309 bool "Support x2apic"
310 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
311 ---help---
312 This enables x2apic support on CPUs that have this feature.
314 This allows 32-bit apic IDs (so it can support very large systems),
315 and accesses the local apic via MSRs not via mmio.
317 If you don't know what to do here, say N.
319 config X86_MPPARSE
320 bool "Enable MPS table" if ACPI || SFI
321 default y
322 depends on X86_LOCAL_APIC
323 ---help---
324 For old smp systems that do not have proper acpi support. Newer systems
325 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
327 config X86_BIGSMP
328 bool "Support for big SMP systems with more than 8 CPUs"
329 depends on X86_32 && SMP
330 ---help---
331 This option is needed for the systems that have more than 8 CPUs
333 config GOLDFISH
334 def_bool y
335 depends on X86_GOLDFISH
337 if X86_32
338 config X86_EXTENDED_PLATFORM
339 bool "Support for extended (non-PC) x86 platforms"
340 default y
341 ---help---
342 If you disable this option then the kernel will only support
343 standard PC platforms. (which covers the vast majority of
344 systems out there.)
346 If you enable this option then you'll be able to select support
347 for the following (non-PC) 32 bit x86 platforms:
348 Goldfish (Android emulator)
349 AMD Elan
350 NUMAQ (IBM/Sequent)
351 RDC R-321x SoC
352 SGI 320/540 (Visual Workstation)
353 STA2X11-based (e.g. Northville)
354 Summit/EXA (IBM x440)
355 Unisys ES7000 IA32 series
356 Moorestown MID devices
358 If you have one of these systems, or if you want to build a
359 generic distribution kernel, say Y here - otherwise say N.
360 endif
362 if X86_64
363 config X86_EXTENDED_PLATFORM
364 bool "Support for extended (non-PC) x86 platforms"
365 default y
366 ---help---
367 If you disable this option then the kernel will only support
368 standard PC platforms. (which covers the vast majority of
369 systems out there.)
371 If you enable this option then you'll be able to select support
372 for the following (non-PC) 64 bit x86 platforms:
373 Numascale NumaChip
374 ScaleMP vSMP
375 SGI Ultraviolet
377 If you have one of these systems, or if you want to build a
378 generic distribution kernel, say Y here - otherwise say N.
379 endif
380 # This is an alphabetically sorted list of 64 bit extended platforms
381 # Please maintain the alphabetic order if and when there are additions
382 config X86_NUMACHIP
383 bool "Numascale NumaChip"
384 depends on X86_64
385 depends on X86_EXTENDED_PLATFORM
386 depends on NUMA
387 depends on SMP
388 depends on X86_X2APIC
389 depends on PCI_MMCONFIG
390 ---help---
391 Adds support for Numascale NumaChip large-SMP systems. Needed to
392 enable more than ~168 cores.
393 If you don't have one of these, you should say N here.
395 config X86_VSMP
396 bool "ScaleMP vSMP"
397 select HYPERVISOR_GUEST
398 select PARAVIRT
399 depends on X86_64 && PCI
400 depends on X86_EXTENDED_PLATFORM
401 depends on SMP
402 ---help---
403 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
404 supposed to run on these EM64T-based machines. Only choose this option
405 if you have one of these machines.
407 config X86_UV
408 bool "SGI Ultraviolet"
409 depends on X86_64
410 depends on X86_EXTENDED_PLATFORM
411 depends on NUMA
412 depends on X86_X2APIC
413 ---help---
414 This option is needed in order to support SGI Ultraviolet systems.
415 If you don't have one of these, you should say N here.
417 # Following is an alphabetically sorted list of 32 bit extended platforms
418 # Please maintain the alphabetic order if and when there are additions
420 config X86_GOLDFISH
421 bool "Goldfish (Virtual Platform)"
422 depends on X86_32
423 depends on X86_EXTENDED_PLATFORM
424 ---help---
425 Enable support for the Goldfish virtual platform used primarily
426 for Android development. Unless you are building for the Android
427 Goldfish emulator say N here.
429 config X86_INTEL_CE
430 bool "CE4100 TV platform"
431 depends on PCI
432 depends on PCI_GODIRECT
433 depends on X86_32
434 depends on X86_EXTENDED_PLATFORM
435 select X86_REBOOTFIXUPS
436 select OF
437 select OF_EARLY_FLATTREE
438 select IRQ_DOMAIN
439 ---help---
440 Select for the Intel CE media processor (CE4100) SOC.
441 This option compiles in support for the CE4100 SOC for settop
442 boxes and media devices.
444 config X86_WANT_INTEL_MID
445 bool "Intel MID platform support"
446 depends on X86_32
447 depends on X86_EXTENDED_PLATFORM
448 ---help---
449 Select to build a kernel capable of supporting Intel MID platform
450 systems which do not have the PCI legacy interfaces (Moorestown,
451 Medfield). If you are building for a PC class system say N here.
453 if X86_WANT_INTEL_MID
455 config X86_INTEL_MID
456 bool
458 config X86_MDFLD
459 bool "Medfield MID platform"
460 depends on PCI
461 depends on PCI_GOANY
462 depends on X86_IO_APIC
463 select X86_INTEL_MID
464 select SFI
465 select DW_APB_TIMER
466 select APB_TIMER
467 select I2C
468 select SPI
469 select INTEL_SCU_IPC
470 select X86_PLATFORM_DEVICES
471 select MFD_INTEL_MSIC
472 ---help---
473 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
474 Internet Device(MID) platform.
475 Unlike standard x86 PCs, Medfield does not have many legacy devices
476 nor standard legacy replacement devices/features. e.g. Medfield does
477 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
479 endif
481 config X86_INTEL_LPSS
482 bool "Intel Low Power Subsystem Support"
483 depends on ACPI
484 select COMMON_CLK
485 select PINCTRL
486 ---help---
487 Select to build support for Intel Low Power Subsystem such as
488 found on Intel Lynxpoint PCH. Selecting this option enables
489 things like clock tree (common clock framework) and pincontrol
490 which are needed by the LPSS peripheral drivers.
492 config X86_RDC321X
493 bool "RDC R-321x SoC"
494 depends on X86_32
495 depends on X86_EXTENDED_PLATFORM
496 select M486
497 select X86_REBOOTFIXUPS
498 ---help---
499 This option is needed for RDC R-321x system-on-chip, also known
500 as R-8610-(G).
501 If you don't have one of these chips, you should say N here.
503 config X86_32_NON_STANDARD
504 bool "Support non-standard 32-bit SMP architectures"
505 depends on X86_32 && SMP
506 depends on X86_EXTENDED_PLATFORM
507 ---help---
508 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
509 STA2X11, default subarchitectures. It is intended for a generic
510 binary kernel. If you select them all, kernel will probe it
511 one by one and will fallback to default.
513 # Alphabetically sorted list of Non standard 32 bit platforms
515 config X86_NUMAQ
516 bool "NUMAQ (IBM/Sequent)"
517 depends on X86_32_NON_STANDARD
518 depends on PCI
519 select NUMA
520 select X86_MPPARSE
521 ---help---
522 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
523 NUMA multiquad box. This changes the way that processors are
524 bootstrapped, and uses Clustered Logical APIC addressing mode instead
525 of Flat Logical. You will need a new lynxer.elf file to flash your
526 firmware with - send email to <Martin.Bligh@us.ibm.com>.
528 config X86_SUPPORTS_MEMORY_FAILURE
529 def_bool y
530 # MCE code calls memory_failure():
531 depends on X86_MCE
532 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
533 depends on !X86_NUMAQ
534 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
535 depends on X86_64 || !SPARSEMEM
536 select ARCH_SUPPORTS_MEMORY_FAILURE
538 config X86_VISWS
539 bool "SGI 320/540 (Visual Workstation)"
540 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
541 depends on X86_32_NON_STANDARD
542 ---help---
543 The SGI Visual Workstation series is an IA32-based workstation
544 based on SGI systems chips with some legacy PC hardware attached.
546 Say Y here to create a kernel to run on the SGI 320 or 540.
548 A kernel compiled for the Visual Workstation will run on general
549 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
551 config STA2X11
552 bool "STA2X11 Companion Chip Support"
553 depends on X86_32_NON_STANDARD && PCI
554 select X86_DEV_DMA_OPS
555 select X86_DMA_REMAP
556 select SWIOTLB
557 select MFD_STA2X11
558 select ARCH_REQUIRE_GPIOLIB
559 default n
560 ---help---
561 This adds support for boards based on the STA2X11 IO-Hub,
562 a.k.a. "ConneXt". The chip is used in place of the standard
563 PC chipset, so all "standard" peripherals are missing. If this
564 option is selected the kernel will still be able to boot on
565 standard PC machines.
567 config X86_SUMMIT
568 bool "Summit/EXA (IBM x440)"
569 depends on X86_32_NON_STANDARD
570 ---help---
571 This option is needed for IBM systems that use the Summit/EXA chipset.
572 In particular, it is needed for the x440.
574 config X86_ES7000
575 bool "Unisys ES7000 IA32 series"
576 depends on X86_32_NON_STANDARD && X86_BIGSMP
577 ---help---
578 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
579 supposed to run on an IA32-based Unisys ES7000 system.
581 config X86_32_IRIS
582 tristate "Eurobraille/Iris poweroff module"
583 depends on X86_32
584 ---help---
585 The Iris machines from EuroBraille do not have APM or ACPI support
586 to shut themselves down properly. A special I/O sequence is
587 needed to do so, which is what this module does at
588 kernel shutdown.
590 This is only for Iris machines from EuroBraille.
592 If unused, say N.
594 config SCHED_OMIT_FRAME_POINTER
595 def_bool y
596 prompt "Single-depth WCHAN output"
597 depends on X86
598 ---help---
599 Calculate simpler /proc/<PID>/wchan values. If this option
600 is disabled then wchan values will recurse back to the
601 caller function. This provides more accurate wchan values,
602 at the expense of slightly more scheduling overhead.
604 If in doubt, say "Y".
606 menuconfig HYPERVISOR_GUEST
607 bool "Linux guest support"
608 ---help---
609 Say Y here to enable options for running Linux under various hyper-
610 visors. This option enables basic hypervisor detection and platform
611 setup.
613 If you say N, all options in this submenu will be skipped and
614 disabled, and Linux guest support won't be built in.
616 if HYPERVISOR_GUEST
618 config PARAVIRT
619 bool "Enable paravirtualization code"
620 ---help---
621 This changes the kernel so it can modify itself when it is run
622 under a hypervisor, potentially improving performance significantly
623 over full virtualization. However, when run without a hypervisor
624 the kernel is theoretically slower and slightly larger.
626 config PARAVIRT_DEBUG
627 bool "paravirt-ops debugging"
628 depends on PARAVIRT && DEBUG_KERNEL
629 ---help---
630 Enable to debug paravirt_ops internals. Specifically, BUG if
631 a paravirt_op is missing when it is called.
633 config PARAVIRT_SPINLOCKS
634 bool "Paravirtualization layer for spinlocks"
635 depends on PARAVIRT && SMP
636 select UNINLINE_SPIN_UNLOCK
637 ---help---
638 Paravirtualized spinlocks allow a pvops backend to replace the
639 spinlock implementation with something virtualization-friendly
640 (for example, block the virtual CPU rather than spinning).
642 Unfortunately the downside is an up to 5% performance hit on
643 native kernels, with various workloads.
645 If you are unsure how to answer this question, answer N.
647 source "arch/x86/xen/Kconfig"
649 config KVM_GUEST
650 bool "KVM Guest support (including kvmclock)"
651 depends on PARAVIRT
652 select PARAVIRT_CLOCK
653 default y
654 ---help---
655 This option enables various optimizations for running under the KVM
656 hypervisor. It includes a paravirtualized clock, so that instead
657 of relying on a PIT (or probably other) emulation by the
658 underlying device model, the host provides the guest with
659 timing infrastructure such as time of day, and system time
661 config KVM_DEBUG_FS
662 bool "Enable debug information for KVM Guests in debugfs"
663 depends on KVM_GUEST && DEBUG_FS
664 default n
665 ---help---
666 This option enables collection of various statistics for KVM guest.
667 Statistics are displayed in debugfs filesystem. Enabling this option
668 may incur significant overhead.
670 source "arch/x86/lguest/Kconfig"
672 config PARAVIRT_TIME_ACCOUNTING
673 bool "Paravirtual steal time accounting"
674 depends on PARAVIRT
675 default n
676 ---help---
677 Select this option to enable fine granularity task steal time
678 accounting. Time spent executing other tasks in parallel with
679 the current vCPU is discounted from the vCPU power. To account for
680 that, there can be a small performance impact.
682 If in doubt, say N here.
684 config PARAVIRT_CLOCK
685 bool
687 endif #HYPERVISOR_GUEST
689 config NO_BOOTMEM
690 def_bool y
692 config MEMTEST
693 bool "Memtest"
694 ---help---
695 This option adds a kernel parameter 'memtest', which allows memtest
696 to be set.
697 memtest=0, mean disabled; -- default
698 memtest=1, mean do 1 test pattern;
699 ...
700 memtest=4, mean do 4 test patterns.
701 If you are unsure how to answer this question, answer N.
703 config X86_SUMMIT_NUMA
704 def_bool y
705 depends on X86_32 && NUMA && X86_32_NON_STANDARD
707 config X86_CYCLONE_TIMER
708 def_bool y
709 depends on X86_SUMMIT
711 source "arch/x86/Kconfig.cpu"
713 config HPET_TIMER
714 def_bool X86_64
715 prompt "HPET Timer Support" if X86_32
716 ---help---
717 Use the IA-PC HPET (High Precision Event Timer) to manage
718 time in preference to the PIT and RTC, if a HPET is
719 present.
720 HPET is the next generation timer replacing legacy 8254s.
721 The HPET provides a stable time base on SMP
722 systems, unlike the TSC, but it is more expensive to access,
723 as it is off-chip. You can find the HPET spec at
724 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
726 You can safely choose Y here. However, HPET will only be
727 activated if the platform and the BIOS support this feature.
728 Otherwise the 8254 will be used for timing services.
730 Choose N to continue using the legacy 8254 timer.
732 config HPET_EMULATE_RTC
733 def_bool y
734 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
736 config APB_TIMER
737 def_bool y if X86_INTEL_MID
738 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
739 select DW_APB_TIMER
740 depends on X86_INTEL_MID && SFI
741 help
742 APB timer is the replacement for 8254, HPET on X86 MID platforms.
743 The APBT provides a stable time base on SMP
744 systems, unlike the TSC, but it is more expensive to access,
745 as it is off-chip. APB timers are always running regardless of CPU
746 C states, they are used as per CPU clockevent device when possible.
748 # Mark as expert because too many people got it wrong.
749 # The code disables itself when not needed.
750 config DMI
751 default y
752 bool "Enable DMI scanning" if EXPERT
753 ---help---
754 Enabled scanning of DMI to identify machine quirks. Say Y
755 here unless you have verified that your setup is not
756 affected by entries in the DMI blacklist. Required by PNP
757 BIOS code.
759 config GART_IOMMU
760 bool "GART IOMMU support" if EXPERT
761 default y
762 select SWIOTLB
763 depends on X86_64 && PCI && AMD_NB
764 ---help---
765 Support for full DMA access of devices with 32bit memory access only
766 on systems with more than 3GB. This is usually needed for USB,
767 sound, many IDE/SATA chipsets and some other devices.
768 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
769 based hardware IOMMU and a software bounce buffer based IOMMU used
770 on Intel systems and as fallback.
771 The code is only active when needed (enough memory and limited
772 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
773 too.
775 config CALGARY_IOMMU
776 bool "IBM Calgary IOMMU support"
777 select SWIOTLB
778 depends on X86_64 && PCI
779 ---help---
780 Support for hardware IOMMUs in IBM's xSeries x366 and x460
781 systems. Needed to run systems with more than 3GB of memory
782 properly with 32-bit PCI devices that do not support DAC
783 (Double Address Cycle). Calgary also supports bus level
784 isolation, where all DMAs pass through the IOMMU. This
785 prevents them from going anywhere except their intended
786 destination. This catches hard-to-find kernel bugs and
787 mis-behaving drivers and devices that do not use the DMA-API
788 properly to set up their DMA buffers. The IOMMU can be
789 turned off at boot time with the iommu=off parameter.
790 Normally the kernel will make the right choice by itself.
791 If unsure, say Y.
793 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
794 def_bool y
795 prompt "Should Calgary be enabled by default?"
796 depends on CALGARY_IOMMU
797 ---help---
798 Should Calgary be enabled by default? if you choose 'y', Calgary
799 will be used (if it exists). If you choose 'n', Calgary will not be
800 used even if it exists. If you choose 'n' and would like to use
801 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
802 If unsure, say Y.
804 # need this always selected by IOMMU for the VIA workaround
805 config SWIOTLB
806 def_bool y if X86_64
807 ---help---
808 Support for software bounce buffers used on x86-64 systems
809 which don't have a hardware IOMMU. Using this PCI devices
810 which can only access 32-bits of memory can be used on systems
811 with more than 3 GB of memory.
812 If unsure, say Y.
814 config IOMMU_HELPER
815 def_bool y
816 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
818 config MAXSMP
819 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
820 depends on X86_64 && SMP && DEBUG_KERNEL
821 select CPUMASK_OFFSTACK
822 ---help---
823 Enable maximum number of CPUS and NUMA Nodes for this architecture.
824 If unsure, say N.
826 config NR_CPUS
827 int "Maximum number of CPUs" if SMP && !MAXSMP
828 range 2 8 if SMP && X86_32 && !X86_BIGSMP
829 range 2 512 if SMP && !MAXSMP
830 default "1" if !SMP
831 default "4096" if MAXSMP
832 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
833 default "8" if SMP
834 ---help---
835 This allows you to specify the maximum number of CPUs which this
836 kernel will support. The maximum supported value is 512 and the
837 minimum value which makes sense is 2.
839 This is purely to save memory - each supported CPU adds
840 approximately eight kilobytes to the kernel image.
842 config SCHED_SMT
843 bool "SMT (Hyperthreading) scheduler support"
844 depends on X86_HT
845 ---help---
846 SMT scheduler support improves the CPU scheduler's decision making
847 when dealing with Intel Pentium 4 chips with HyperThreading at a
848 cost of slightly increased overhead in some places. If unsure say
849 N here.
851 config SCHED_MC
852 def_bool y
853 prompt "Multi-core scheduler support"
854 depends on X86_HT
855 ---help---
856 Multi-core scheduler support improves the CPU scheduler's decision
857 making when dealing with multi-core CPU chips at a cost of slightly
858 increased overhead in some places. If unsure say N here.
860 source "kernel/Kconfig.preempt"
862 config X86_UP_APIC
863 bool "Local APIC support on uniprocessors"
864 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
865 ---help---
866 A local APIC (Advanced Programmable Interrupt Controller) is an
867 integrated interrupt controller in the CPU. If you have a single-CPU
868 system which has a processor with a local APIC, you can say Y here to
869 enable and use it. If you say Y here even though your machine doesn't
870 have a local APIC, then the kernel will still run with no slowdown at
871 all. The local APIC supports CPU-generated self-interrupts (timer,
872 performance counters), and the NMI watchdog which detects hard
873 lockups.
875 config X86_UP_APIC_MSI
876 def_bool y
877 select X86_UP_APIC if X86_32 && !SMP && !X86_32_NON_STANDARD && PCI_MSI
879 config X86_UP_IOAPIC
880 bool "IO-APIC support on uniprocessors"
881 depends on X86_UP_APIC
882 ---help---
883 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
884 SMP-capable replacement for PC-style interrupt controllers. Most
885 SMP systems and many recent uniprocessor systems have one.
887 If you have a single-CPU system with an IO-APIC, you can say Y here
888 to use it. If you say Y here even though your machine doesn't have
889 an IO-APIC, then the kernel will still run with no slowdown at all.
891 config X86_LOCAL_APIC
892 def_bool y
893 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
895 config X86_IO_APIC
896 def_bool y
897 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
899 config X86_VISWS_APIC
900 def_bool y
901 depends on X86_32 && X86_VISWS
903 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
904 bool "Reroute for broken boot IRQs"
905 depends on X86_IO_APIC
906 ---help---
907 This option enables a workaround that fixes a source of
908 spurious interrupts. This is recommended when threaded
909 interrupt handling is used on systems where the generation of
910 superfluous "boot interrupts" cannot be disabled.
912 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
913 entry in the chipset's IO-APIC is masked (as, e.g. the RT
914 kernel does during interrupt handling). On chipsets where this
915 boot IRQ generation cannot be disabled, this workaround keeps
916 the original IRQ line masked so that only the equivalent "boot
917 IRQ" is delivered to the CPUs. The workaround also tells the
918 kernel to set up the IRQ handler on the boot IRQ line. In this
919 way only one interrupt is delivered to the kernel. Otherwise
920 the spurious second interrupt may cause the kernel to bring
921 down (vital) interrupt lines.
923 Only affects "broken" chipsets. Interrupt sharing may be
924 increased on these systems.
926 config X86_MCE
927 bool "Machine Check / overheating reporting"
928 default y
929 ---help---
930 Machine Check support allows the processor to notify the
931 kernel if it detects a problem (e.g. overheating, data corruption).
932 The action the kernel takes depends on the severity of the problem,
933 ranging from warning messages to halting the machine.
935 config X86_MCE_INTEL
936 def_bool y
937 prompt "Intel MCE features"
938 depends on X86_MCE && X86_LOCAL_APIC
939 ---help---
940 Additional support for intel specific MCE features such as
941 the thermal monitor.
943 config X86_MCE_AMD
944 def_bool y
945 prompt "AMD MCE features"
946 depends on X86_MCE && X86_LOCAL_APIC
947 ---help---
948 Additional support for AMD specific MCE features such as
949 the DRAM Error Threshold.
951 config X86_ANCIENT_MCE
952 bool "Support for old Pentium 5 / WinChip machine checks"
953 depends on X86_32 && X86_MCE
954 ---help---
955 Include support for machine check handling on old Pentium 5 or WinChip
956 systems. These typically need to be enabled explicitely on the command
957 line.
959 config X86_MCE_THRESHOLD
960 depends on X86_MCE_AMD || X86_MCE_INTEL
961 def_bool y
963 config X86_MCE_INJECT
964 depends on X86_MCE
965 tristate "Machine check injector support"
966 ---help---
967 Provide support for injecting machine checks for testing purposes.
968 If you don't know what a machine check is and you don't do kernel
969 QA it is safe to say n.
971 config X86_THERMAL_VECTOR
972 def_bool y
973 depends on X86_MCE_INTEL
975 config VM86
976 bool "Enable VM86 support" if EXPERT
977 default y
978 depends on X86_32
979 ---help---
980 This option is required by programs like DOSEMU to run
981 16-bit real mode legacy code on x86 processors. It also may
982 be needed by software like XFree86 to initialize some video
983 cards via BIOS. Disabling this option saves about 6K.
985 config X86_16BIT
986 bool "Enable support for 16-bit segments" if EXPERT
987 default y
988 ---help---
989 This option is required by programs like Wine to run 16-bit
990 protected mode legacy code on x86 processors. Disabling
991 this option saves about 300 bytes on i386, or around 6K text
992 plus 16K runtime memory on x86-64,
994 config X86_ESPFIX32
995 def_bool y
996 depends on X86_16BIT && X86_32
998 config X86_ESPFIX64
999 def_bool y
1000 depends on X86_16BIT && X86_64
1002 config TOSHIBA
1003 tristate "Toshiba Laptop support"
1004 depends on X86_32
1005 ---help---
1006 This adds a driver to safely access the System Management Mode of
1007 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1008 not work on models with a Phoenix BIOS. The System Management Mode
1009 is used to set the BIOS and power saving options on Toshiba portables.
1011 For information on utilities to make use of this driver see the
1012 Toshiba Linux utilities web site at:
1013 <http://www.buzzard.org.uk/toshiba/>.
1015 Say Y if you intend to run this kernel on a Toshiba portable.
1016 Say N otherwise.
1018 config I8K
1019 tristate "Dell laptop support"
1020 select HWMON
1021 ---help---
1022 This adds a driver to safely access the System Management Mode
1023 of the CPU on the Dell Inspiron 8000. The System Management Mode
1024 is used to read cpu temperature and cooling fan status and to
1025 control the fans on the I8K portables.
1027 This driver has been tested only on the Inspiron 8000 but it may
1028 also work with other Dell laptops. You can force loading on other
1029 models by passing the parameter `force=1' to the module. Use at
1030 your own risk.
1032 For information on utilities to make use of this driver see the
1033 I8K Linux utilities web site at:
1034 <http://people.debian.org/~dz/i8k/>
1036 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1037 Say N otherwise.
1039 config X86_REBOOTFIXUPS
1040 bool "Enable X86 board specific fixups for reboot"
1041 depends on X86_32
1042 ---help---
1043 This enables chipset and/or board specific fixups to be done
1044 in order to get reboot to work correctly. This is only needed on
1045 some combinations of hardware and BIOS. The symptom, for which
1046 this config is intended, is when reboot ends with a stalled/hung
1047 system.
1049 Currently, the only fixup is for the Geode machines using
1050 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1052 Say Y if you want to enable the fixup. Currently, it's safe to
1053 enable this option even if you don't need it.
1054 Say N otherwise.
1056 config MICROCODE
1057 tristate "CPU microcode loading support"
1058 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1059 select FW_LOADER
1060 ---help---
1062 If you say Y here, you will be able to update the microcode on
1063 certain Intel and AMD processors. The Intel support is for the
1064 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1065 Xeon etc. The AMD support is for families 0x10 and later. You will
1066 obviously need the actual microcode binary data itself which is not
1067 shipped with the Linux kernel.
1069 This option selects the general module only, you need to select
1070 at least one vendor specific module as well.
1072 To compile this driver as a module, choose M here: the module
1073 will be called microcode.
1075 config MICROCODE_INTEL
1076 bool "Intel microcode loading support"
1077 depends on MICROCODE
1078 default MICROCODE
1079 select FW_LOADER
1080 ---help---
1081 This options enables microcode patch loading support for Intel
1082 processors.
1084 For latest news and information on obtaining all the required
1085 Intel ingredients for this driver, check:
1086 <http://www.urbanmyth.org/microcode/>.
1088 config MICROCODE_AMD
1089 bool "AMD microcode loading support"
1090 depends on MICROCODE
1091 select FW_LOADER
1092 ---help---
1093 If you select this option, microcode patch loading support for AMD
1094 processors will be enabled.
1096 config MICROCODE_OLD_INTERFACE
1097 def_bool y
1098 depends on MICROCODE
1100 config MICROCODE_INTEL_LIB
1101 def_bool y
1102 depends on MICROCODE_INTEL
1104 config MICROCODE_INTEL_EARLY
1105 def_bool n
1107 config MICROCODE_AMD_EARLY
1108 def_bool n
1110 config MICROCODE_EARLY
1111 bool "Early load microcode"
1112 depends on MICROCODE=y && BLK_DEV_INITRD
1113 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1114 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1115 default y
1116 help
1117 This option provides functionality to read additional microcode data
1118 at the beginning of initrd image. The data tells kernel to load
1119 microcode to CPU's as early as possible. No functional change if no
1120 microcode data is glued to the initrd, therefore it's safe to say Y.
1122 config X86_MSR
1123 tristate "/dev/cpu/*/msr - Model-specific register support"
1124 ---help---
1125 This device gives privileged processes access to the x86
1126 Model-Specific Registers (MSRs). It is a character device with
1127 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1128 MSR accesses are directed to a specific CPU on multi-processor
1129 systems.
1131 config X86_CPUID
1132 tristate "/dev/cpu/*/cpuid - CPU information support"
1133 ---help---
1134 This device gives processes access to the x86 CPUID instruction to
1135 be executed on a specific processor. It is a character device
1136 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1137 /dev/cpu/31/cpuid.
1139 choice
1140 prompt "High Memory Support"
1141 default HIGHMEM64G if X86_NUMAQ
1142 default HIGHMEM4G
1143 depends on X86_32
1145 config NOHIGHMEM
1146 bool "off"
1147 depends on !X86_NUMAQ
1148 ---help---
1149 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1150 However, the address space of 32-bit x86 processors is only 4
1151 Gigabytes large. That means that, if you have a large amount of
1152 physical memory, not all of it can be "permanently mapped" by the
1153 kernel. The physical memory that's not permanently mapped is called
1154 "high memory".
1156 If you are compiling a kernel which will never run on a machine with
1157 more than 1 Gigabyte total physical RAM, answer "off" here (default
1158 choice and suitable for most users). This will result in a "3GB/1GB"
1159 split: 3GB are mapped so that each process sees a 3GB virtual memory
1160 space and the remaining part of the 4GB virtual memory space is used
1161 by the kernel to permanently map as much physical memory as
1162 possible.
1164 If the machine has between 1 and 4 Gigabytes physical RAM, then
1165 answer "4GB" here.
1167 If more than 4 Gigabytes is used then answer "64GB" here. This
1168 selection turns Intel PAE (Physical Address Extension) mode on.
1169 PAE implements 3-level paging on IA32 processors. PAE is fully
1170 supported by Linux, PAE mode is implemented on all recent Intel
1171 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1172 then the kernel will not boot on CPUs that don't support PAE!
1174 The actual amount of total physical memory will either be
1175 auto detected or can be forced by using a kernel command line option
1176 such as "mem=256M". (Try "man bootparam" or see the documentation of
1177 your boot loader (lilo or loadlin) about how to pass options to the
1178 kernel at boot time.)
1180 If unsure, say "off".
1182 config HIGHMEM4G
1183 bool "4GB"
1184 depends on !X86_NUMAQ
1185 ---help---
1186 Select this if you have a 32-bit processor and between 1 and 4
1187 gigabytes of physical RAM.
1189 config HIGHMEM64G
1190 bool "64GB"
1191 depends on !M486
1192 select X86_PAE
1193 ---help---
1194 Select this if you have a 32-bit processor and more than 4
1195 gigabytes of physical RAM.
1197 endchoice
1199 choice
1200 prompt "Memory split" if EXPERT
1201 default VMSPLIT_3G
1202 depends on X86_32
1203 ---help---
1204 Select the desired split between kernel and user memory.
1206 If the address range available to the kernel is less than the
1207 physical memory installed, the remaining memory will be available
1208 as "high memory". Accessing high memory is a little more costly
1209 than low memory, as it needs to be mapped into the kernel first.
1210 Note that increasing the kernel address space limits the range
1211 available to user programs, making the address space there
1212 tighter. Selecting anything other than the default 3G/1G split
1213 will also likely make your kernel incompatible with binary-only
1214 kernel modules.
1216 If you are not absolutely sure what you are doing, leave this
1217 option alone!
1219 config VMSPLIT_3G
1220 bool "3G/1G user/kernel split"
1221 config VMSPLIT_3G_OPT
1222 depends on !X86_PAE
1223 bool "3G/1G user/kernel split (for full 1G low memory)"
1224 config VMSPLIT_2G
1225 bool "2G/2G user/kernel split"
1226 config VMSPLIT_2G_OPT
1227 depends on !X86_PAE
1228 bool "2G/2G user/kernel split (for full 2G low memory)"
1229 config VMSPLIT_1G
1230 bool "1G/3G user/kernel split"
1231 endchoice
1233 config PAGE_OFFSET
1234 hex
1235 default 0xB0000000 if VMSPLIT_3G_OPT
1236 default 0x80000000 if VMSPLIT_2G
1237 default 0x78000000 if VMSPLIT_2G_OPT
1238 default 0x40000000 if VMSPLIT_1G
1239 default 0xC0000000
1240 depends on X86_32
1242 config HIGHMEM
1243 def_bool y
1244 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1246 config X86_PAE
1247 bool "PAE (Physical Address Extension) Support"
1248 depends on X86_32 && !HIGHMEM4G
1249 ---help---
1250 PAE is required for NX support, and furthermore enables
1251 larger swapspace support for non-overcommit purposes. It
1252 has the cost of more pagetable lookup overhead, and also
1253 consumes more pagetable space per process.
1255 config ARCH_PHYS_ADDR_T_64BIT
1256 def_bool y
1257 depends on X86_64 || X86_PAE
1259 config ARCH_DMA_ADDR_T_64BIT
1260 def_bool y
1261 depends on X86_64 || HIGHMEM64G
1263 config DIRECT_GBPAGES
1264 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1265 default y
1266 depends on X86_64
1267 ---help---
1268 Allow the kernel linear mapping to use 1GB pages on CPUs that
1269 support it. This can improve the kernel's performance a tiny bit by
1270 reducing TLB pressure. If in doubt, say "Y".
1272 # Common NUMA Features
1273 config NUMA
1274 bool "Numa Memory Allocation and Scheduler Support"
1275 depends on SMP
1276 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1277 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1278 ---help---
1279 Enable NUMA (Non Uniform Memory Access) support.
1281 The kernel will try to allocate memory used by a CPU on the
1282 local memory controller of the CPU and add some more
1283 NUMA awareness to the kernel.
1285 For 64-bit this is recommended if the system is Intel Core i7
1286 (or later), AMD Opteron, or EM64T NUMA.
1288 For 32-bit this is only needed on (rare) 32-bit-only platforms
1289 that support NUMA topologies, such as NUMAQ / Summit, or if you
1290 boot a 32-bit kernel on a 64-bit NUMA platform.
1292 Otherwise, you should say N.
1294 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1295 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1297 config AMD_NUMA
1298 def_bool y
1299 prompt "Old style AMD Opteron NUMA detection"
1300 depends on X86_64 && NUMA && PCI
1301 ---help---
1302 Enable AMD NUMA node topology detection. You should say Y here if
1303 you have a multi processor AMD system. This uses an old method to
1304 read the NUMA configuration directly from the builtin Northbridge
1305 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1306 which also takes priority if both are compiled in.
1308 config X86_64_ACPI_NUMA
1309 def_bool y
1310 prompt "ACPI NUMA detection"
1311 depends on X86_64 && NUMA && ACPI && PCI
1312 select ACPI_NUMA
1313 ---help---
1314 Enable ACPI SRAT based node topology detection.
1316 # Some NUMA nodes have memory ranges that span
1317 # other nodes. Even though a pfn is valid and
1318 # between a node's start and end pfns, it may not
1319 # reside on that node. See memmap_init_zone()
1320 # for details.
1321 config NODES_SPAN_OTHER_NODES
1322 def_bool y
1323 depends on X86_64_ACPI_NUMA
1325 config NUMA_EMU
1326 bool "NUMA emulation"
1327 depends on NUMA
1328 ---help---
1329 Enable NUMA emulation. A flat machine will be split
1330 into virtual nodes when booted with "numa=fake=N", where N is the
1331 number of nodes. This is only useful for debugging.
1333 config NODES_SHIFT
1334 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1335 range 1 10
1336 default "10" if MAXSMP
1337 default "6" if X86_64
1338 default "4" if X86_NUMAQ
1339 default "3"
1340 depends on NEED_MULTIPLE_NODES
1341 ---help---
1342 Specify the maximum number of NUMA Nodes available on the target
1343 system. Increases memory reserved to accommodate various tables.
1345 config ARCH_HAVE_MEMORY_PRESENT
1346 def_bool y
1347 depends on X86_32 && DISCONTIGMEM
1349 config NEED_NODE_MEMMAP_SIZE
1350 def_bool y
1351 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1353 config ARCH_FLATMEM_ENABLE
1354 def_bool y
1355 depends on X86_32 && !NUMA
1357 config ARCH_DISCONTIGMEM_ENABLE
1358 def_bool y
1359 depends on NUMA && X86_32
1361 config ARCH_DISCONTIGMEM_DEFAULT
1362 def_bool y
1363 depends on NUMA && X86_32
1365 config ARCH_SPARSEMEM_ENABLE
1366 def_bool y
1367 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1368 select SPARSEMEM_STATIC if X86_32
1369 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1371 config ARCH_SPARSEMEM_DEFAULT
1372 def_bool y
1373 depends on X86_64
1375 config ARCH_SELECT_MEMORY_MODEL
1376 def_bool y
1377 depends on ARCH_SPARSEMEM_ENABLE
1379 config ARCH_MEMORY_PROBE
1380 bool "Enable sysfs memory/probe interface"
1381 depends on X86_64 && MEMORY_HOTPLUG
1382 help
1383 This option enables a sysfs memory/probe interface for testing.
1384 See Documentation/memory-hotplug.txt for more information.
1385 If you are unsure how to answer this question, answer N.
1387 config ARCH_PROC_KCORE_TEXT
1388 def_bool y
1389 depends on X86_64 && PROC_KCORE
1391 config ILLEGAL_POINTER_VALUE
1392 hex
1393 default 0 if X86_32
1394 default 0xdead000000000000 if X86_64
1396 source "mm/Kconfig"
1398 config HIGHPTE
1399 bool "Allocate 3rd-level pagetables from highmem"
1400 depends on HIGHMEM
1401 ---help---
1402 The VM uses one page table entry for each page of physical memory.
1403 For systems with a lot of RAM, this can be wasteful of precious
1404 low memory. Setting this option will put user-space page table
1405 entries in high memory.
1407 config X86_CHECK_BIOS_CORRUPTION
1408 bool "Check for low memory corruption"
1409 ---help---
1410 Periodically check for memory corruption in low memory, which
1411 is suspected to be caused by BIOS. Even when enabled in the
1412 configuration, it is disabled at runtime. Enable it by
1413 setting "memory_corruption_check=1" on the kernel command
1414 line. By default it scans the low 64k of memory every 60
1415 seconds; see the memory_corruption_check_size and
1416 memory_corruption_check_period parameters in
1417 Documentation/kernel-parameters.txt to adjust this.
1419 When enabled with the default parameters, this option has
1420 almost no overhead, as it reserves a relatively small amount
1421 of memory and scans it infrequently. It both detects corruption
1422 and prevents it from affecting the running system.
1424 It is, however, intended as a diagnostic tool; if repeatable
1425 BIOS-originated corruption always affects the same memory,
1426 you can use memmap= to prevent the kernel from using that
1427 memory.
1429 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1430 bool "Set the default setting of memory_corruption_check"
1431 depends on X86_CHECK_BIOS_CORRUPTION
1432 default y
1433 ---help---
1434 Set whether the default state of memory_corruption_check is
1435 on or off.
1437 config X86_RESERVE_LOW
1438 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1439 default 64
1440 range 4 640
1441 ---help---
1442 Specify the amount of low memory to reserve for the BIOS.
1444 The first page contains BIOS data structures that the kernel
1445 must not use, so that page must always be reserved.
1447 By default we reserve the first 64K of physical RAM, as a
1448 number of BIOSes are known to corrupt that memory range
1449 during events such as suspend/resume or monitor cable
1450 insertion, so it must not be used by the kernel.
1452 You can set this to 4 if you are absolutely sure that you
1453 trust the BIOS to get all its memory reservations and usages
1454 right. If you know your BIOS have problems beyond the
1455 default 64K area, you can set this to 640 to avoid using the
1456 entire low memory range.
1458 If you have doubts about the BIOS (e.g. suspend/resume does
1459 not work or there's kernel crashes after certain hardware
1460 hotplug events) then you might want to enable
1461 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1462 typical corruption patterns.
1464 Leave this to the default value of 64 if you are unsure.
1466 config MATH_EMULATION
1467 bool
1468 prompt "Math emulation" if X86_32
1469 ---help---
1470 Linux can emulate a math coprocessor (used for floating point
1471 operations) if you don't have one. 486DX and Pentium processors have
1472 a math coprocessor built in, 486SX and 386 do not, unless you added
1473 a 487DX or 387, respectively. (The messages during boot time can
1474 give you some hints here ["man dmesg"].) Everyone needs either a
1475 coprocessor or this emulation.
1477 If you don't have a math coprocessor, you need to say Y here; if you
1478 say Y here even though you have a coprocessor, the coprocessor will
1479 be used nevertheless. (This behavior can be changed with the kernel
1480 command line option "no387", which comes handy if your coprocessor
1481 is broken. Try "man bootparam" or see the documentation of your boot
1482 loader (lilo or loadlin) about how to pass options to the kernel at
1483 boot time.) This means that it is a good idea to say Y here if you
1484 intend to use this kernel on different machines.
1486 More information about the internals of the Linux math coprocessor
1487 emulation can be found in <file:arch/x86/math-emu/README>.
1489 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1490 kernel, it won't hurt.
1492 config MTRR
1493 def_bool y
1494 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1495 ---help---
1496 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1497 the Memory Type Range Registers (MTRRs) may be used to control
1498 processor access to memory ranges. This is most useful if you have
1499 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1500 allows bus write transfers to be combined into a larger transfer
1501 before bursting over the PCI/AGP bus. This can increase performance
1502 of image write operations 2.5 times or more. Saying Y here creates a
1503 /proc/mtrr file which may be used to manipulate your processor's
1504 MTRRs. Typically the X server should use this.
1506 This code has a reasonably generic interface so that similar
1507 control registers on other processors can be easily supported
1508 as well:
1510 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1511 Registers (ARRs) which provide a similar functionality to MTRRs. For
1512 these, the ARRs are used to emulate the MTRRs.
1513 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1514 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1515 write-combining. All of these processors are supported by this code
1516 and it makes sense to say Y here if you have one of them.
1518 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1519 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1520 can lead to all sorts of problems, so it's good to say Y here.
1522 You can safely say Y even if your machine doesn't have MTRRs, you'll
1523 just add about 9 KB to your kernel.
1525 See <file:Documentation/x86/mtrr.txt> for more information.
1527 config MTRR_SANITIZER
1528 def_bool y
1529 prompt "MTRR cleanup support"
1530 depends on MTRR
1531 ---help---
1532 Convert MTRR layout from continuous to discrete, so X drivers can
1533 add writeback entries.
1535 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1536 The largest mtrr entry size for a continuous block can be set with
1537 mtrr_chunk_size.
1539 If unsure, say Y.
1541 config MTRR_SANITIZER_ENABLE_DEFAULT
1542 int "MTRR cleanup enable value (0-1)"
1543 range 0 1
1544 default "0"
1545 depends on MTRR_SANITIZER
1546 ---help---
1547 Enable mtrr cleanup default value
1549 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1550 int "MTRR cleanup spare reg num (0-7)"
1551 range 0 7
1552 default "1"
1553 depends on MTRR_SANITIZER
1554 ---help---
1555 mtrr cleanup spare entries default, it can be changed via
1556 mtrr_spare_reg_nr=N on the kernel command line.
1558 config X86_PAT
1559 def_bool y
1560 prompt "x86 PAT support" if EXPERT
1561 depends on MTRR
1562 ---help---
1563 Use PAT attributes to setup page level cache control.
1565 PATs are the modern equivalents of MTRRs and are much more
1566 flexible than MTRRs.
1568 Say N here if you see bootup problems (boot crash, boot hang,
1569 spontaneous reboots) or a non-working video driver.
1571 If unsure, say Y.
1573 config ARCH_USES_PG_UNCACHED
1574 def_bool y
1575 depends on X86_PAT
1577 config ARCH_RANDOM
1578 def_bool y
1579 prompt "x86 architectural random number generator" if EXPERT
1580 ---help---
1581 Enable the x86 architectural RDRAND instruction
1582 (Intel Bull Mountain technology) to generate random numbers.
1583 If supported, this is a high bandwidth, cryptographically
1584 secure hardware random number generator.
1586 config X86_SMAP
1587 def_bool y
1588 prompt "Supervisor Mode Access Prevention" if EXPERT
1589 ---help---
1590 Supervisor Mode Access Prevention (SMAP) is a security
1591 feature in newer Intel processors. There is a small
1592 performance cost if this enabled and turned on; there is
1593 also a small increase in the kernel size if this is enabled.
1595 If unsure, say Y.
1597 config EFI
1598 bool "EFI runtime service support"
1599 depends on ACPI
1600 select UCS2_STRING
1601 ---help---
1602 This enables the kernel to use EFI runtime services that are
1603 available (such as the EFI variable services).
1605 This option is only useful on systems that have EFI firmware.
1606 In addition, you should use the latest ELILO loader available
1607 at <http://elilo.sourceforge.net> in order to take advantage
1608 of EFI runtime services. However, even with this option, the
1609 resultant kernel should continue to boot on existing non-EFI
1610 platforms.
1612 config EFI_STUB
1613 bool "EFI stub support"
1614 depends on EFI
1615 select RELOCATABLE
1616 ---help---
1617 This kernel feature allows a bzImage to be loaded directly
1618 by EFI firmware without the use of a bootloader.
1620 See Documentation/x86/efi-stub.txt for more information.
1622 config SECCOMP
1623 def_bool y
1624 prompt "Enable seccomp to safely compute untrusted bytecode"
1625 ---help---
1626 This kernel feature is useful for number crunching applications
1627 that may need to compute untrusted bytecode during their
1628 execution. By using pipes or other transports made available to
1629 the process as file descriptors supporting the read/write
1630 syscalls, it's possible to isolate those applications in
1631 their own address space using seccomp. Once seccomp is
1632 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1633 and the task is only allowed to execute a few safe syscalls
1634 defined by each seccomp mode.
1636 If unsure, say Y. Only embedded should say N here.
1638 config CC_STACKPROTECTOR
1639 bool "Enable -fstack-protector buffer overflow detection"
1640 ---help---
1641 This option turns on the -fstack-protector GCC feature. This
1642 feature puts, at the beginning of functions, a canary value on
1643 the stack just before the return address, and validates
1644 the value just before actually returning. Stack based buffer
1645 overflows (that need to overwrite this return address) now also
1646 overwrite the canary, which gets detected and the attack is then
1647 neutralized via a kernel panic.
1649 This feature requires gcc version 4.2 or above, or a distribution
1650 gcc with the feature backported. Older versions are automatically
1651 detected and for those versions, this configuration option is
1652 ignored. (and a warning is printed during bootup)
1654 source kernel/Kconfig.hz
1656 config KEXEC
1657 bool "kexec system call"
1658 ---help---
1659 kexec is a system call that implements the ability to shutdown your
1660 current kernel, and to start another kernel. It is like a reboot
1661 but it is independent of the system firmware. And like a reboot
1662 you can start any kernel with it, not just Linux.
1664 The name comes from the similarity to the exec system call.
1666 It is an ongoing process to be certain the hardware in a machine
1667 is properly shutdown, so do not be surprised if this code does not
1668 initially work for you. As of this writing the exact hardware
1669 interface is strongly in flux, so no good recommendation can be
1670 made.
1672 config CRASH_DUMP
1673 bool "kernel crash dumps"
1674 depends on X86_64 || (X86_32 && HIGHMEM)
1675 ---help---
1676 Generate crash dump after being started by kexec.
1677 This should be normally only set in special crash dump kernels
1678 which are loaded in the main kernel with kexec-tools into
1679 a specially reserved region and then later executed after
1680 a crash by kdump/kexec. The crash dump kernel must be compiled
1681 to a memory address not used by the main kernel or BIOS using
1682 PHYSICAL_START, or it must be built as a relocatable image
1683 (CONFIG_RELOCATABLE=y).
1684 For more details see Documentation/kdump/kdump.txt
1686 config KEXEC_JUMP
1687 bool "kexec jump"
1688 depends on KEXEC && HIBERNATION
1689 ---help---
1690 Jump between original kernel and kexeced kernel and invoke
1691 code in physical address mode via KEXEC
1693 config PHYSICAL_START
1694 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1695 default "0x1000000"
1696 ---help---
1697 This gives the physical address where the kernel is loaded.
1699 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1700 bzImage will decompress itself to above physical address and
1701 run from there. Otherwise, bzImage will run from the address where
1702 it has been loaded by the boot loader and will ignore above physical
1703 address.
1705 In normal kdump cases one does not have to set/change this option
1706 as now bzImage can be compiled as a completely relocatable image
1707 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1708 address. This option is mainly useful for the folks who don't want
1709 to use a bzImage for capturing the crash dump and want to use a
1710 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1711 to be specifically compiled to run from a specific memory area
1712 (normally a reserved region) and this option comes handy.
1714 So if you are using bzImage for capturing the crash dump,
1715 leave the value here unchanged to 0x1000000 and set
1716 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1717 for capturing the crash dump change this value to start of
1718 the reserved region. In other words, it can be set based on
1719 the "X" value as specified in the "crashkernel=YM@XM"
1720 command line boot parameter passed to the panic-ed
1721 kernel. Please take a look at Documentation/kdump/kdump.txt
1722 for more details about crash dumps.
1724 Usage of bzImage for capturing the crash dump is recommended as
1725 one does not have to build two kernels. Same kernel can be used
1726 as production kernel and capture kernel. Above option should have
1727 gone away after relocatable bzImage support is introduced. But it
1728 is present because there are users out there who continue to use
1729 vmlinux for dump capture. This option should go away down the
1730 line.
1732 Don't change this unless you know what you are doing.
1734 config RELOCATABLE
1735 bool "Build a relocatable kernel"
1736 default y
1737 ---help---
1738 This builds a kernel image that retains relocation information
1739 so it can be loaded someplace besides the default 1MB.
1740 The relocations tend to make the kernel binary about 10% larger,
1741 but are discarded at runtime.
1743 One use is for the kexec on panic case where the recovery kernel
1744 must live at a different physical address than the primary
1745 kernel.
1747 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1748 it has been loaded at and the compile time physical address
1749 (CONFIG_PHYSICAL_START) is ignored.
1751 # Relocation on x86-32 needs some additional build support
1752 config X86_NEED_RELOCS
1753 def_bool y
1754 depends on X86_32 && RELOCATABLE
1756 config PHYSICAL_ALIGN
1757 hex "Alignment value to which kernel should be aligned"
1758 default "0x1000000"
1759 range 0x2000 0x1000000 if X86_32
1760 range 0x200000 0x1000000 if X86_64
1761 ---help---
1762 This value puts the alignment restrictions on physical address
1763 where kernel is loaded and run from. Kernel is compiled for an
1764 address which meets above alignment restriction.
1766 If bootloader loads the kernel at a non-aligned address and
1767 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1768 address aligned to above value and run from there.
1770 If bootloader loads the kernel at a non-aligned address and
1771 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1772 load address and decompress itself to the address it has been
1773 compiled for and run from there. The address for which kernel is
1774 compiled already meets above alignment restrictions. Hence the
1775 end result is that kernel runs from a physical address meeting
1776 above alignment restrictions.
1778 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1779 this value must be a multiple of 0x200000.
1781 Don't change this unless you know what you are doing.
1783 config HOTPLUG_CPU
1784 bool "Support for hot-pluggable CPUs"
1785 depends on SMP
1786 ---help---
1787 Say Y here to allow turning CPUs off and on. CPUs can be
1788 controlled through /sys/devices/system/cpu.
1789 ( Note: power management support will enable this option
1790 automatically on SMP systems. )
1791 Say N if you want to disable CPU hotplug.
1793 config BOOTPARAM_HOTPLUG_CPU0
1794 bool "Set default setting of cpu0_hotpluggable"
1795 default n
1796 depends on HOTPLUG_CPU
1797 ---help---
1798 Set whether default state of cpu0_hotpluggable is on or off.
1800 Say Y here to enable CPU0 hotplug by default. If this switch
1801 is turned on, there is no need to give cpu0_hotplug kernel
1802 parameter and the CPU0 hotplug feature is enabled by default.
1804 Please note: there are two known CPU0 dependencies if you want
1805 to enable the CPU0 hotplug feature either by this switch or by
1806 cpu0_hotplug kernel parameter.
1808 First, resume from hibernate or suspend always starts from CPU0.
1809 So hibernate and suspend are prevented if CPU0 is offline.
1811 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1812 offline if any interrupt can not migrate out of CPU0. There may
1813 be other CPU0 dependencies.
1815 Please make sure the dependencies are under your control before
1816 you enable this feature.
1818 Say N if you don't want to enable CPU0 hotplug feature by default.
1819 You still can enable the CPU0 hotplug feature at boot by kernel
1820 parameter cpu0_hotplug.
1822 config DEBUG_HOTPLUG_CPU0
1823 def_bool n
1824 prompt "Debug CPU0 hotplug"
1825 depends on HOTPLUG_CPU
1826 ---help---
1827 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1828 soon as possible and boots up userspace with CPU0 offlined. User
1829 can online CPU0 back after boot time.
1831 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1832 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1833 compilation or giving cpu0_hotplug kernel parameter at boot.
1835 If unsure, say N.
1837 config COMPAT_VDSO
1838 def_bool y
1839 prompt "Compat VDSO support"
1840 depends on X86_32 || IA32_EMULATION
1841 ---help---
1842 Map the 32-bit VDSO to the predictable old-style address too.
1844 Say N here if you are running a sufficiently recent glibc
1845 version (2.3.3 or later), to remove the high-mapped
1846 VDSO mapping and to exclusively use the randomized VDSO.
1848 If unsure, say Y.
1850 config CMDLINE_BOOL
1851 bool "Built-in kernel command line"
1852 ---help---
1853 Allow for specifying boot arguments to the kernel at
1854 build time. On some systems (e.g. embedded ones), it is
1855 necessary or convenient to provide some or all of the
1856 kernel boot arguments with the kernel itself (that is,
1857 to not rely on the boot loader to provide them.)
1859 To compile command line arguments into the kernel,
1860 set this option to 'Y', then fill in the
1861 the boot arguments in CONFIG_CMDLINE.
1863 Systems with fully functional boot loaders (i.e. non-embedded)
1864 should leave this option set to 'N'.
1866 config CMDLINE
1867 string "Built-in kernel command string"
1868 depends on CMDLINE_BOOL
1869 default ""
1870 ---help---
1871 Enter arguments here that should be compiled into the kernel
1872 image and used at boot time. If the boot loader provides a
1873 command line at boot time, it is appended to this string to
1874 form the full kernel command line, when the system boots.
1876 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1877 change this behavior.
1879 In most cases, the command line (whether built-in or provided
1880 by the boot loader) should specify the device for the root
1881 file system.
1883 config CMDLINE_OVERRIDE
1884 bool "Built-in command line overrides boot loader arguments"
1885 depends on CMDLINE_BOOL
1886 ---help---
1887 Set this option to 'Y' to have the kernel ignore the boot loader
1888 command line, and use ONLY the built-in command line.
1890 This is used to work around broken boot loaders. This should
1891 be set to 'N' under normal conditions.
1893 endmenu
1895 config ARCH_ENABLE_MEMORY_HOTPLUG
1896 def_bool y
1897 depends on X86_64 || (X86_32 && HIGHMEM)
1899 config ARCH_ENABLE_MEMORY_HOTREMOVE
1900 def_bool y
1901 depends on MEMORY_HOTPLUG
1903 config USE_PERCPU_NUMA_NODE_ID
1904 def_bool y
1905 depends on NUMA
1907 config ARCH_ENABLE_HUGEPAGE_MIGRATION
1908 def_bool y
1909 depends on X86_64 && HUGETLB_PAGE && MIGRATION
1911 menu "Power management and ACPI options"
1913 config ARCH_HIBERNATION_HEADER
1914 def_bool y
1915 depends on X86_64 && HIBERNATION
1917 source "kernel/power/Kconfig"
1919 source "drivers/acpi/Kconfig"
1921 source "drivers/sfi/Kconfig"
1923 config X86_APM_BOOT
1924 def_bool y
1925 depends on APM
1927 menuconfig APM
1928 tristate "APM (Advanced Power Management) BIOS support"
1929 depends on X86_32 && PM_SLEEP
1930 ---help---
1931 APM is a BIOS specification for saving power using several different
1932 techniques. This is mostly useful for battery powered laptops with
1933 APM compliant BIOSes. If you say Y here, the system time will be
1934 reset after a RESUME operation, the /proc/apm device will provide
1935 battery status information, and user-space programs will receive
1936 notification of APM "events" (e.g. battery status change).
1938 If you select "Y" here, you can disable actual use of the APM
1939 BIOS by passing the "apm=off" option to the kernel at boot time.
1941 Note that the APM support is almost completely disabled for
1942 machines with more than one CPU.
1944 In order to use APM, you will need supporting software. For location
1945 and more information, read <file:Documentation/power/apm-acpi.txt>
1946 and the Battery Powered Linux mini-HOWTO, available from
1947 <http://www.tldp.org/docs.html#howto>.
1949 This driver does not spin down disk drives (see the hdparm(8)
1950 manpage ("man 8 hdparm") for that), and it doesn't turn off
1951 VESA-compliant "green" monitors.
1953 This driver does not support the TI 4000M TravelMate and the ACER
1954 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1955 desktop machines also don't have compliant BIOSes, and this driver
1956 may cause those machines to panic during the boot phase.
1958 Generally, if you don't have a battery in your machine, there isn't
1959 much point in using this driver and you should say N. If you get
1960 random kernel OOPSes or reboots that don't seem to be related to
1961 anything, try disabling/enabling this option (or disabling/enabling
1962 APM in your BIOS).
1964 Some other things you should try when experiencing seemingly random,
1965 "weird" problems:
1967 1) make sure that you have enough swap space and that it is
1968 enabled.
1969 2) pass the "no-hlt" option to the kernel
1970 3) switch on floating point emulation in the kernel and pass
1971 the "no387" option to the kernel
1972 4) pass the "floppy=nodma" option to the kernel
1973 5) pass the "mem=4M" option to the kernel (thereby disabling
1974 all but the first 4 MB of RAM)
1975 6) make sure that the CPU is not over clocked.
1976 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1977 8) disable the cache from your BIOS settings
1978 9) install a fan for the video card or exchange video RAM
1979 10) install a better fan for the CPU
1980 11) exchange RAM chips
1981 12) exchange the motherboard.
1983 To compile this driver as a module, choose M here: the
1984 module will be called apm.
1986 if APM
1988 config APM_IGNORE_USER_SUSPEND
1989 bool "Ignore USER SUSPEND"
1990 ---help---
1991 This option will ignore USER SUSPEND requests. On machines with a
1992 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1993 series notebooks, it is necessary to say Y because of a BIOS bug.
1995 config APM_DO_ENABLE
1996 bool "Enable PM at boot time"
1997 ---help---
1998 Enable APM features at boot time. From page 36 of the APM BIOS
1999 specification: "When disabled, the APM BIOS does not automatically
2000 power manage devices, enter the Standby State, enter the Suspend
2001 State, or take power saving steps in response to CPU Idle calls."
2002 This driver will make CPU Idle calls when Linux is idle (unless this
2003 feature is turned off -- see "Do CPU IDLE calls", below). This
2004 should always save battery power, but more complicated APM features
2005 will be dependent on your BIOS implementation. You may need to turn
2006 this option off if your computer hangs at boot time when using APM
2007 support, or if it beeps continuously instead of suspending. Turn
2008 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2009 T400CDT. This is off by default since most machines do fine without
2010 this feature.
2012 config APM_CPU_IDLE
2013 depends on CPU_IDLE
2014 bool "Make CPU Idle calls when idle"
2015 ---help---
2016 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2017 On some machines, this can activate improved power savings, such as
2018 a slowed CPU clock rate, when the machine is idle. These idle calls
2019 are made after the idle loop has run for some length of time (e.g.,
2020 333 mS). On some machines, this will cause a hang at boot time or
2021 whenever the CPU becomes idle. (On machines with more than one CPU,
2022 this option does nothing.)
2024 config APM_DISPLAY_BLANK
2025 bool "Enable console blanking using APM"
2026 ---help---
2027 Enable console blanking using the APM. Some laptops can use this to
2028 turn off the LCD backlight when the screen blanker of the Linux
2029 virtual console blanks the screen. Note that this is only used by
2030 the virtual console screen blanker, and won't turn off the backlight
2031 when using the X Window system. This also doesn't have anything to
2032 do with your VESA-compliant power-saving monitor. Further, this
2033 option doesn't work for all laptops -- it might not turn off your
2034 backlight at all, or it might print a lot of errors to the console,
2035 especially if you are using gpm.
2037 config APM_ALLOW_INTS
2038 bool "Allow interrupts during APM BIOS calls"
2039 ---help---
2040 Normally we disable external interrupts while we are making calls to
2041 the APM BIOS as a measure to lessen the effects of a badly behaving
2042 BIOS implementation. The BIOS should reenable interrupts if it
2043 needs to. Unfortunately, some BIOSes do not -- especially those in
2044 many of the newer IBM Thinkpads. If you experience hangs when you
2045 suspend, try setting this to Y. Otherwise, say N.
2047 endif # APM
2049 source "drivers/cpufreq/Kconfig"
2051 source "drivers/cpuidle/Kconfig"
2053 source "drivers/idle/Kconfig"
2055 endmenu
2058 menu "Bus options (PCI etc.)"
2060 config PCI
2061 bool "PCI support"
2062 default y
2063 ---help---
2064 Find out whether you have a PCI motherboard. PCI is the name of a
2065 bus system, i.e. the way the CPU talks to the other stuff inside
2066 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2067 VESA. If you have PCI, say Y, otherwise N.
2069 choice
2070 prompt "PCI access mode"
2071 depends on X86_32 && PCI
2072 default PCI_GOANY
2073 ---help---
2074 On PCI systems, the BIOS can be used to detect the PCI devices and
2075 determine their configuration. However, some old PCI motherboards
2076 have BIOS bugs and may crash if this is done. Also, some embedded
2077 PCI-based systems don't have any BIOS at all. Linux can also try to
2078 detect the PCI hardware directly without using the BIOS.
2080 With this option, you can specify how Linux should detect the
2081 PCI devices. If you choose "BIOS", the BIOS will be used,
2082 if you choose "Direct", the BIOS won't be used, and if you
2083 choose "MMConfig", then PCI Express MMCONFIG will be used.
2084 If you choose "Any", the kernel will try MMCONFIG, then the
2085 direct access method and falls back to the BIOS if that doesn't
2086 work. If unsure, go with the default, which is "Any".
2088 config PCI_GOBIOS
2089 bool "BIOS"
2091 config PCI_GOMMCONFIG
2092 bool "MMConfig"
2094 config PCI_GODIRECT
2095 bool "Direct"
2097 config PCI_GOOLPC
2098 bool "OLPC XO-1"
2099 depends on OLPC
2101 config PCI_GOANY
2102 bool "Any"
2104 endchoice
2106 config PCI_BIOS
2107 def_bool y
2108 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2110 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2111 config PCI_DIRECT
2112 def_bool y
2113 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2115 config PCI_MMCONFIG
2116 def_bool y
2117 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2119 config PCI_OLPC
2120 def_bool y
2121 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2123 config PCI_XEN
2124 def_bool y
2125 depends on PCI && XEN
2126 select SWIOTLB_XEN
2128 config PCI_DOMAINS
2129 def_bool y
2130 depends on PCI
2132 config PCI_MMCONFIG
2133 bool "Support mmconfig PCI config space access"
2134 depends on X86_64 && PCI && ACPI
2136 config PCI_CNB20LE_QUIRK
2137 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2138 depends on PCI
2139 help
2140 Read the PCI windows out of the CNB20LE host bridge. This allows
2141 PCI hotplug to work on systems with the CNB20LE chipset which do
2142 not have ACPI.
2144 There's no public spec for this chipset, and this functionality
2145 is known to be incomplete.
2147 You should say N unless you know you need this.
2149 source "drivers/pci/pcie/Kconfig"
2151 source "drivers/pci/Kconfig"
2153 # x86_64 have no ISA slots, but can have ISA-style DMA.
2154 config ISA_DMA_API
2155 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2156 default y
2157 help
2158 Enables ISA-style DMA support for devices requiring such controllers.
2159 If unsure, say Y.
2161 if X86_32
2163 config ISA
2164 bool "ISA support"
2165 ---help---
2166 Find out whether you have ISA slots on your motherboard. ISA is the
2167 name of a bus system, i.e. the way the CPU talks to the other stuff
2168 inside your box. Other bus systems are PCI, EISA, MicroChannel
2169 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2170 newer boards don't support it. If you have ISA, say Y, otherwise N.
2172 config EISA
2173 bool "EISA support"
2174 depends on ISA
2175 ---help---
2176 The Extended Industry Standard Architecture (EISA) bus was
2177 developed as an open alternative to the IBM MicroChannel bus.
2179 The EISA bus provided some of the features of the IBM MicroChannel
2180 bus while maintaining backward compatibility with cards made for
2181 the older ISA bus. The EISA bus saw limited use between 1988 and
2182 1995 when it was made obsolete by the PCI bus.
2184 Say Y here if you are building a kernel for an EISA-based machine.
2186 Otherwise, say N.
2188 source "drivers/eisa/Kconfig"
2190 config SCx200
2191 tristate "NatSemi SCx200 support"
2192 ---help---
2193 This provides basic support for National Semiconductor's
2194 (now AMD's) Geode processors. The driver probes for the
2195 PCI-IDs of several on-chip devices, so its a good dependency
2196 for other scx200_* drivers.
2198 If compiled as a module, the driver is named scx200.
2200 config SCx200HR_TIMER
2201 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2202 depends on SCx200
2203 default y
2204 ---help---
2205 This driver provides a clocksource built upon the on-chip
2206 27MHz high-resolution timer. Its also a workaround for
2207 NSC Geode SC-1100's buggy TSC, which loses time when the
2208 processor goes idle (as is done by the scheduler). The
2209 other workaround is idle=poll boot option.
2211 config OLPC
2212 bool "One Laptop Per Child support"
2213 depends on !X86_PAE
2214 select GPIOLIB
2215 select OF
2216 select OF_PROMTREE
2217 select IRQ_DOMAIN
2218 ---help---
2219 Add support for detecting the unique features of the OLPC
2220 XO hardware.
2222 config OLPC_XO1_PM
2223 bool "OLPC XO-1 Power Management"
2224 depends on OLPC && MFD_CS5535 && PM_SLEEP
2225 select MFD_CORE
2226 ---help---
2227 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2229 config OLPC_XO1_RTC
2230 bool "OLPC XO-1 Real Time Clock"
2231 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2232 ---help---
2233 Add support for the XO-1 real time clock, which can be used as a
2234 programmable wakeup source.
2236 config OLPC_XO1_SCI
2237 bool "OLPC XO-1 SCI extras"
2238 depends on OLPC && OLPC_XO1_PM
2239 depends on INPUT=y
2240 select POWER_SUPPLY
2241 select GPIO_CS5535
2242 select MFD_CORE
2243 ---help---
2244 Add support for SCI-based features of the OLPC XO-1 laptop:
2245 - EC-driven system wakeups
2246 - Power button
2247 - Ebook switch
2248 - Lid switch
2249 - AC adapter status updates
2250 - Battery status updates
2252 config OLPC_XO15_SCI
2253 bool "OLPC XO-1.5 SCI extras"
2254 depends on OLPC && ACPI
2255 select POWER_SUPPLY
2256 ---help---
2257 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2258 - EC-driven system wakeups
2259 - AC adapter status updates
2260 - Battery status updates
2262 config ALIX
2263 bool "PCEngines ALIX System Support (LED setup)"
2264 select GPIOLIB
2265 ---help---
2266 This option enables system support for the PCEngines ALIX.
2267 At present this just sets up LEDs for GPIO control on
2268 ALIX2/3/6 boards. However, other system specific setup should
2269 get added here.
2271 Note: You must still enable the drivers for GPIO and LED support
2272 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2274 Note: You have to set alix.force=1 for boards with Award BIOS.
2276 config NET5501
2277 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2278 select GPIOLIB
2279 ---help---
2280 This option enables system support for the Soekris Engineering net5501.
2282 config GEOS
2283 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2284 select GPIOLIB
2285 depends on DMI
2286 ---help---
2287 This option enables system support for the Traverse Technologies GEOS.
2289 config TS5500
2290 bool "Technologic Systems TS-5500 platform support"
2291 depends on MELAN
2292 select CHECK_SIGNATURE
2293 select NEW_LEDS
2294 select LEDS_CLASS
2295 ---help---
2296 This option enables system support for the Technologic Systems TS-5500.
2298 endif # X86_32
2300 config AMD_NB
2301 def_bool y
2302 depends on CPU_SUP_AMD && PCI
2304 source "drivers/pcmcia/Kconfig"
2306 source "drivers/pci/hotplug/Kconfig"
2308 config RAPIDIO
2309 tristate "RapidIO support"
2310 depends on PCI
2311 default n
2312 help
2313 If enabled this option will include drivers and the core
2314 infrastructure code to support RapidIO interconnect devices.
2316 source "drivers/rapidio/Kconfig"
2318 config X86_SYSFB
2319 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2320 help
2321 Firmwares often provide initial graphics framebuffers so the BIOS,
2322 bootloader or kernel can show basic video-output during boot for
2323 user-guidance and debugging. Historically, x86 used the VESA BIOS
2324 Extensions and EFI-framebuffers for this, which are mostly limited
2325 to x86.
2326 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2327 framebuffers so the new generic system-framebuffer drivers can be
2328 used on x86. If the framebuffer is not compatible with the generic
2329 modes, it is adverticed as fallback platform framebuffer so legacy
2330 drivers like efifb, vesafb and uvesafb can pick it up.
2331 If this option is not selected, all system framebuffers are always
2332 marked as fallback platform framebuffers as usual.
2334 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2335 not be able to pick up generic system framebuffers if this option
2336 is selected. You are highly encouraged to enable simplefb as
2337 replacement if you select this option. simplefb can correctly deal
2338 with generic system framebuffers. But you should still keep vesafb
2339 and others enabled as fallback if a system framebuffer is
2340 incompatible with simplefb.
2342 If unsure, say Y.
2344 endmenu
2347 menu "Executable file formats / Emulations"
2349 source "fs/Kconfig.binfmt"
2351 config IA32_EMULATION
2352 bool "IA32 Emulation"
2353 depends on X86_64
2354 select BINFMT_ELF
2355 select COMPAT_BINFMT_ELF
2356 select HAVE_UID16
2357 ---help---
2358 Include code to run legacy 32-bit programs under a
2359 64-bit kernel. You should likely turn this on, unless you're
2360 100% sure that you don't have any 32-bit programs left.
2362 config IA32_AOUT
2363 tristate "IA32 a.out support"
2364 depends on IA32_EMULATION
2365 ---help---
2366 Support old a.out binaries in the 32bit emulation.
2368 config X86_X32
2369 bool "x32 ABI for 64-bit mode"
2370 depends on X86_64 && IA32_EMULATION
2371 ---help---
2372 Include code to run binaries for the x32 native 32-bit ABI
2373 for 64-bit processors. An x32 process gets access to the
2374 full 64-bit register file and wide data path while leaving
2375 pointers at 32 bits for smaller memory footprint.
2377 You will need a recent binutils (2.22 or later) with
2378 elf32_x86_64 support enabled to compile a kernel with this
2379 option set.
2381 config COMPAT
2382 def_bool y
2383 depends on IA32_EMULATION || X86_X32
2384 select ARCH_WANT_OLD_COMPAT_IPC
2386 if COMPAT
2387 config COMPAT_FOR_U64_ALIGNMENT
2388 def_bool y
2390 config SYSVIPC_COMPAT
2391 def_bool y
2392 depends on SYSVIPC
2394 config KEYS_COMPAT
2395 def_bool y
2396 depends on KEYS
2397 endif
2399 endmenu
2402 config HAVE_ATOMIC_IOMAP
2403 def_bool y
2404 depends on X86_32
2406 config X86_DEV_DMA_OPS
2407 bool
2408 depends on X86_64 || STA2X11
2410 config X86_DMA_REMAP
2411 bool
2412 depends on STA2X11
2414 source "net/Kconfig"
2416 source "drivers/Kconfig"
2418 source "drivers/firmware/Kconfig"
2420 source "fs/Kconfig"
2422 source "arch/x86/Kconfig.debug"
2424 source "security/Kconfig"
2426 source "crypto/Kconfig"
2428 source "arch/x86/kvm/Kconfig"
2430 source "lib/Kconfig"