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x86-32: Fix dummy trampoline-related inline stubs
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1032c0ba 1# x86 configuration
daa93fab
SR
2mainmenu "Linux Kernel Configuration for x86"
3
4# Select 32 or 64 bit
5config 64BIT
6840999b
SR
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
8f9ca475 8 ---help---
daa93fab
SR
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
11
12config X86_32
13 def_bool !64BIT
14
15config X86_64
16 def_bool 64BIT
1032c0ba
SR
17
18### Arch settings
8d5fffb9 19config X86
3c2362e6 20 def_bool y
e17c6d56 21 select HAVE_AOUT if X86_32
2c5643b1
HM
22 select HAVE_READQ
23 select HAVE_WRITEQ
a5574cf6 24 select HAVE_UNSTABLE_SCHED_CLOCK
ec7748b5 25 select HAVE_IDE
42d4b839 26 select HAVE_OPROFILE
cdd6c482 27 select HAVE_PERF_EVENTS if (!M386 && !M486)
28b2ee20 28 select HAVE_IOREMAP_PROT
3f550096 29 select HAVE_KPROBES
1f972768 30 select ARCH_WANT_OPTIONAL_GPIOLIB
da4276b8 31 select ARCH_WANT_FRAME_POINTERS
7c095e46 32 select HAVE_DMA_ATTRS
9edddaa2 33 select HAVE_KRETPROBES
c0f7ac3a 34 select HAVE_OPTPROBES
e4b2b886 35 select HAVE_FTRACE_MCOUNT_RECORD
677aa9f7 36 select HAVE_DYNAMIC_FTRACE
606576ce 37 select HAVE_FUNCTION_TRACER
48d68b20 38 select HAVE_FUNCTION_GRAPH_TRACER
71e308a2 39 select HAVE_FUNCTION_GRAPH_FP_TEST
60a7ecf4 40 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
9a5fd902 41 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
66700001 42 select HAVE_SYSCALL_TRACEPOINTS
e0ec9483 43 select HAVE_KVM
49793b03 44 select HAVE_ARCH_KGDB
99bbc4b1 45 select HAVE_ARCH_TRACEHOOK
323ec001 46 select HAVE_GENERIC_DMA_COHERENT if X86_32
58340a07 47 select HAVE_EFFICIENT_UNALIGNED_ACCESS
8d26487f 48 select USER_STACKTRACE_SUPPORT
f850c30c 49 select HAVE_REGS_AND_STACK_ACCESS_API
2118d0c5 50 select HAVE_DMA_API_DEBUG
2e9f3bdd
PA
51 select HAVE_KERNEL_GZIP
52 select HAVE_KERNEL_BZIP2
53 select HAVE_KERNEL_LZMA
13510997 54 select HAVE_KERNEL_LZO
0067f129 55 select HAVE_HW_BREAKPOINT
0102752e 56 select HAVE_MIXED_BREAKPOINTS_REGS
99e8c5a3 57 select PERF_EVENTS
c01d4323 58 select HAVE_PERF_EVENTS_NMI
99e8c5a3 59 select ANON_INODES
0a4af3b0 60 select HAVE_ARCH_KMEMCHECK
7c68af6e 61 select HAVE_USER_RETURN_NOTIFIER
7d8330a5 62
ba7e4d13
IM
63config INSTRUCTION_DECODER
64 def_bool (KPROBES || PERF_EVENTS)
65
51b26ada
LT
66config OUTPUT_FORMAT
67 string
68 default "elf32-i386" if X86_32
69 default "elf64-x86-64" if X86_64
70
73531905 71config ARCH_DEFCONFIG
b9b39bfb 72 string
73531905
SR
73 default "arch/x86/configs/i386_defconfig" if X86_32
74 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 75
8d5fffb9 76config GENERIC_CMOS_UPDATE
3c2362e6 77 def_bool y
8d5fffb9
SR
78
79config CLOCKSOURCE_WATCHDOG
3c2362e6 80 def_bool y
8d5fffb9
SR
81
82config GENERIC_CLOCKEVENTS
3c2362e6 83 def_bool y
8d5fffb9
SR
84
85config GENERIC_CLOCKEVENTS_BROADCAST
3c2362e6 86 def_bool y
8d5fffb9
SR
87 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
88
89config LOCKDEP_SUPPORT
3c2362e6 90 def_bool y
8d5fffb9
SR
91
92config STACKTRACE_SUPPORT
3c2362e6 93 def_bool y
8d5fffb9 94
aa7d9350
HC
95config HAVE_LATENCYTOP_SUPPORT
96 def_bool y
97
8d5fffb9 98config MMU
3c2362e6 99 def_bool y
8d5fffb9
SR
100
101config ZONE_DMA
3c2362e6 102 def_bool y
8d5fffb9 103
8d5fffb9
SR
104config SBUS
105 bool
106
3bc4e459
FT
107config NEED_DMA_MAP_STATE
108 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
109
18e98307 110config NEED_SG_DMA_LENGTH
4a14d84e 111 def_bool y
18e98307 112
8d5fffb9 113config GENERIC_ISA_DMA
3c2362e6 114 def_bool y
8d5fffb9
SR
115
116config GENERIC_IOMAP
3c2362e6 117 def_bool y
8d5fffb9
SR
118
119config GENERIC_BUG
3c2362e6 120 def_bool y
8d5fffb9 121 depends on BUG
b93a531e
JB
122 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
123
124config GENERIC_BUG_RELATIVE_POINTERS
125 bool
8d5fffb9
SR
126
127config GENERIC_HWEIGHT
3c2362e6 128 def_bool y
8d5fffb9 129
a6082959 130config GENERIC_GPIO
9ba16087 131 bool
a6082959 132
8d5fffb9 133config ARCH_MAY_HAVE_PC_FDC
3c2362e6 134 def_bool y
8d5fffb9 135
1032c0ba
SR
136config RWSEM_GENERIC_SPINLOCK
137 def_bool !X86_XADD
138
139config RWSEM_XCHGADD_ALGORITHM
140 def_bool X86_XADD
141
a6869cc4
VP
142config ARCH_HAS_CPU_IDLE_WAIT
143 def_bool y
144
1032c0ba
SR
145config GENERIC_CALIBRATE_DELAY
146 def_bool y
147
8d5fffb9
SR
148config GENERIC_TIME_VSYSCALL
149 bool
150 default X86_64
151
9a0b8415 152config ARCH_HAS_CPU_RELAX
153 def_bool y
154
89cedfef
VP
155config ARCH_HAS_DEFAULT_IDLE
156 def_bool y
157
1b27d05b
PE
158config ARCH_HAS_CACHE_LINE_SIZE
159 def_bool y
160
dd5af90a 161config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 162 def_bool y
b32ef636 163
08fc4580
TH
164config NEED_PER_CPU_EMBED_FIRST_CHUNK
165 def_bool y
166
167config NEED_PER_CPU_PAGE_FIRST_CHUNK
11124411
TH
168 def_bool y
169
9f0e8d04
MT
170config HAVE_CPUMASK_OF_CPU_MAP
171 def_bool X86_64_SMP
172
801e4062
JB
173config ARCH_HIBERNATION_POSSIBLE
174 def_bool y
801e4062 175
f4cb5700
JB
176config ARCH_SUSPEND_POSSIBLE
177 def_bool y
f4cb5700 178
8d5fffb9
SR
179config ZONE_DMA32
180 bool
181 default X86_64
182
183config ARCH_POPULATES_NODE_MAP
184 def_bool y
185
186config AUDIT_ARCH
187 bool
188 default X86_64
189
765c68bd
IM
190config ARCH_SUPPORTS_OPTIMIZED_INLINING
191 def_bool y
192
6a11f75b
AM
193config ARCH_SUPPORTS_DEBUG_PAGEALLOC
194 def_bool y
195
580e0ad2
YL
196config HAVE_EARLY_RES
197 def_bool y
198
69575d38
SW
199config HAVE_INTEL_TXT
200 def_bool y
201 depends on EXPERIMENTAL && DMAR && ACPI
202
8d5fffb9
SR
203# Use the generic interrupt handling code in kernel/irq/:
204config GENERIC_HARDIRQS
6fc108a0 205 def_bool y
8d5fffb9 206
f9a36fa5
TG
207config GENERIC_HARDIRQS_NO__DO_IRQ
208 def_bool y
209
8d5fffb9 210config GENERIC_IRQ_PROBE
6fc108a0 211 def_bool y
8d5fffb9
SR
212
213config GENERIC_PENDING_IRQ
6fc108a0 214 def_bool y
8d5fffb9 215 depends on GENERIC_HARDIRQS && SMP
8d5fffb9 216
6cd10f8d
JB
217config USE_GENERIC_SMP_HELPERS
218 def_bool y
219 depends on SMP
220
6b0c3d44
SR
221config X86_32_SMP
222 def_bool y
223 depends on X86_32 && SMP
224
225config X86_64_SMP
226 def_bool y
227 depends on X86_64 && SMP
228
8d5fffb9 229config X86_HT
6fc108a0 230 def_bool y
ee0011a7 231 depends on SMP
8d5fffb9
SR
232
233config X86_TRAMPOLINE
6fc108a0 234 def_bool y
3e5095d1 235 depends on SMP || (64BIT && ACPI_SLEEP)
8d5fffb9 236
ccbeed3a
TH
237config X86_32_LAZY_GS
238 def_bool y
60a5317f 239 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 240
d61931d8
BP
241config ARCH_HWEIGHT_CFLAGS
242 string
243 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
244 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
245
8d5fffb9
SR
246config KTIME_SCALAR
247 def_bool X86_32
506f1d07 248source "init/Kconfig"
dc52ddc0 249source "kernel/Kconfig.freezer"
8d5fffb9 250
506f1d07
SR
251menu "Processor type and features"
252
253source "kernel/time/Kconfig"
254
255config SMP
256 bool "Symmetric multi-processing support"
257 ---help---
258 This enables support for systems with more than one CPU. If you have
259 a system with only one CPU, like most personal computers, say N. If
260 you have a system with more than one CPU, say Y.
261
262 If you say N here, the kernel will run on single and multiprocessor
263 machines, but will use only one CPU of a multiprocessor machine. If
264 you say Y here, the kernel will run on many, but not all,
265 singleprocessor machines. On a singleprocessor machine, the kernel
266 will run faster if you say N here.
267
268 Note that if you say Y here and choose architecture "586" or
269 "Pentium" under "Processor family", the kernel will not work on 486
270 architectures. Similarly, multiprocessor kernels for the "PPro"
271 architecture may not work on all Pentium based boards.
272
273 People using multiprocessor machines who say Y here should also say
274 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
275 Management" code will be disabled if you say Y here.
276
03502faa 277 See also <file:Documentation/i386/IO-APIC.txt>,
506f1d07
SR
278 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
279 <http://www.tldp.org/docs.html#howto>.
280
281 If you don't know what to do here, say N.
282
06cd9a7d
YL
283config X86_X2APIC
284 bool "Support x2apic"
f7d7f866 285 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
06cd9a7d
YL
286 ---help---
287 This enables x2apic support on CPUs that have this feature.
288
289 This allows 32-bit apic IDs (so it can support very large systems),
290 and accesses the local apic via MSRs not via mmio.
291
06cd9a7d
YL
292 If you don't know what to do here, say N.
293
0b8f1efa
YL
294config SPARSE_IRQ
295 bool "Support sparse irq numbering"
17483a1f 296 depends on PCI_MSI || HT_IRQ
8f9ca475 297 ---help---
973656fe
IM
298 This enables support for sparse irqs. This is useful for distro
299 kernels that want to define a high CONFIG_NR_CPUS value but still
300 want to have low kernel memory footprint on smaller machines.
0b8f1efa 301
973656fe
IM
302 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
303 out the irq_desc[] array in a more NUMA-friendly way. )
304
305 If you don't know what to do here, say N.
0b8f1efa 306
15e957d0
YL
307config NUMA_IRQ_DESC
308 def_bool y
b9098957 309 depends on SPARSE_IRQ && NUMA
48a1b10a 310
6695c85b 311config X86_MPPARSE
7a527688
JB
312 bool "Enable MPS table" if ACPI
313 default y
5ab74722 314 depends on X86_LOCAL_APIC
8f9ca475 315 ---help---
6695c85b
YL
316 For old smp systems that do not have proper acpi support. Newer systems
317 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 318
26f7ef14
YL
319config X86_BIGSMP
320 bool "Support for big SMP systems with more than 8 CPUs"
321 depends on X86_32 && SMP
8f9ca475 322 ---help---
26f7ef14 323 This option is needed for the systems that have more than 8 CPUs
506f1d07 324
8425091f 325if X86_32
c5c606d9
RT
326config X86_EXTENDED_PLATFORM
327 bool "Support for extended (non-PC) x86 platforms"
328 default y
8f9ca475 329 ---help---
06ac8346
IM
330 If you disable this option then the kernel will only support
331 standard PC platforms. (which covers the vast majority of
332 systems out there.)
333
8425091f
RT
334 If you enable this option then you'll be able to select support
335 for the following (non-PC) 32 bit x86 platforms:
336 AMD Elan
337 NUMAQ (IBM/Sequent)
338 RDC R-321x SoC
339 SGI 320/540 (Visual Workstation)
340 Summit/EXA (IBM x440)
341 Unisys ES7000 IA32 series
3f4110a4 342 Moorestown MID devices
06ac8346
IM
343
344 If you have one of these systems, or if you want to build a
345 generic distribution kernel, say Y here - otherwise say N.
8425091f 346endif
06ac8346 347
8425091f
RT
348if X86_64
349config X86_EXTENDED_PLATFORM
350 bool "Support for extended (non-PC) x86 platforms"
351 default y
352 ---help---
353 If you disable this option then the kernel will only support
354 standard PC platforms. (which covers the vast majority of
355 systems out there.)
356
357 If you enable this option then you'll be able to select support
358 for the following (non-PC) 64 bit x86 platforms:
359 ScaleMP vSMP
360 SGI Ultraviolet
361
362 If you have one of these systems, or if you want to build a
363 generic distribution kernel, say Y here - otherwise say N.
364endif
c5c606d9
RT
365# This is an alphabetically sorted list of 64 bit extended platforms
366# Please maintain the alphabetic order if and when there are additions
506f1d07 367
c5c606d9
RT
368config X86_VSMP
369 bool "ScaleMP vSMP"
370 select PARAVIRT
371 depends on X86_64 && PCI
372 depends on X86_EXTENDED_PLATFORM
8f9ca475 373 ---help---
c5c606d9
RT
374 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
375 supposed to run on these EM64T-based machines. Only choose this option
376 if you have one of these machines.
5e3a77e9 377
03b48632
NP
378config X86_UV
379 bool "SGI Ultraviolet"
380 depends on X86_64
c5c606d9 381 depends on X86_EXTENDED_PLATFORM
54c28d29 382 depends on NUMA
9d6c26e7 383 depends on X86_X2APIC
8f9ca475 384 ---help---
03b48632
NP
385 This option is needed in order to support SGI Ultraviolet systems.
386 If you don't have one of these, you should say N here.
387
c5c606d9
RT
388# Following is an alphabetically sorted list of 32 bit extended platforms
389# Please maintain the alphabetic order if and when there are additions
506f1d07
SR
390
391config X86_ELAN
392 bool "AMD Elan"
393 depends on X86_32
c5c606d9 394 depends on X86_EXTENDED_PLATFORM
8f9ca475 395 ---help---
506f1d07
SR
396 Select this for an AMD Elan processor.
397
398 Do not use this option for K6/Athlon/Opteron processors!
399
400 If unsure, choose "PC-compatible" instead.
401
3f4110a4
TG
402config X86_MRST
403 bool "Moorestown MID platform"
4b2f3f7d
JP
404 depends on PCI
405 depends on PCI_GOANY
3f4110a4
TG
406 depends on X86_32
407 depends on X86_EXTENDED_PLATFORM
4b2f3f7d 408 depends on X86_IO_APIC
bb24c471 409 select APB_TIMER
3f4110a4
TG
410 ---help---
411 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
412 Internet Device(MID) platform. Moorestown consists of two chips:
413 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
414 Unlike standard x86 PCs, Moorestown does not have many legacy devices
415 nor standard legacy replacement devices/features. e.g. Moorestown does
416 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
417
c5c606d9
RT
418config X86_RDC321X
419 bool "RDC R-321x SoC"
506f1d07 420 depends on X86_32
c5c606d9
RT
421 depends on X86_EXTENDED_PLATFORM
422 select M486
423 select X86_REBOOTFIXUPS
424 ---help---
425 This option is needed for RDC R-321x system-on-chip, also known
426 as R-8610-(G).
427 If you don't have one of these chips, you should say N here.
428
e0c7ae37 429config X86_32_NON_STANDARD
9c398017
IM
430 bool "Support non-standard 32-bit SMP architectures"
431 depends on X86_32 && SMP
c5c606d9 432 depends on X86_EXTENDED_PLATFORM
8f9ca475
IM
433 ---help---
434 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
d49c4288
YL
435 subarchitectures. It is intended for a generic binary kernel.
436 if you select them all, kernel will probe it one by one. and will
437 fallback to default.
438
c5c606d9 439# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 440
506f1d07
SR
441config X86_NUMAQ
442 bool "NUMAQ (IBM/Sequent)"
e0c7ae37 443 depends on X86_32_NON_STANDARD
a92d152e 444 depends on PCI
506f1d07 445 select NUMA
9c398017 446 select X86_MPPARSE
8f9ca475 447 ---help---
d49c4288
YL
448 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
449 NUMA multiquad box. This changes the way that processors are
450 bootstrapped, and uses Clustered Logical APIC addressing mode instead
451 of Flat Logical. You will need a new lynxer.elf file to flash your
452 firmware with - send email to <Martin.Bligh@us.ibm.com>.
506f1d07 453
d949f36f 454config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 455 def_bool y
d949f36f
LT
456 # MCE code calls memory_failure():
457 depends on X86_MCE
458 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
459 depends on !X86_NUMAQ
460 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
461 depends on X86_64 || !SPARSEMEM
462 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 463
1b84e1c8
IM
464config X86_VISWS
465 bool "SGI 320/540 (Visual Workstation)"
c5c606d9
RT
466 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
467 depends on X86_32_NON_STANDARD
468 ---help---
1b84e1c8
IM
469 The SGI Visual Workstation series is an IA32-based workstation
470 based on SGI systems chips with some legacy PC hardware attached.
471
472 Say Y here to create a kernel to run on the SGI 320 or 540.
473
474 A kernel compiled for the Visual Workstation will run on general
475 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
476
9c398017
IM
477config X86_SUMMIT
478 bool "Summit/EXA (IBM x440)"
e0c7ae37 479 depends on X86_32_NON_STANDARD
8f9ca475 480 ---help---
9c398017
IM
481 This option is needed for IBM systems that use the Summit/EXA chipset.
482 In particular, it is needed for the x440.
1f972768 483
9c398017 484config X86_ES7000
c5c606d9 485 bool "Unisys ES7000 IA32 series"
26f7ef14 486 depends on X86_32_NON_STANDARD && X86_BIGSMP
8f9ca475 487 ---help---
9c398017
IM
488 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
489 supposed to run on an IA32-based Unisys ES7000 system.
490
ae1e9130 491config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
492 def_bool y
493 prompt "Single-depth WCHAN output"
a87d0914 494 depends on X86
8f9ca475 495 ---help---
506f1d07
SR
496 Calculate simpler /proc/<PID>/wchan values. If this option
497 is disabled then wchan values will recurse back to the
498 caller function. This provides more accurate wchan values,
499 at the expense of slightly more scheduling overhead.
500
501 If in doubt, say "Y".
502
506f1d07
SR
503menuconfig PARAVIRT_GUEST
504 bool "Paravirtualized guest support"
8f9ca475 505 ---help---
506f1d07
SR
506 Say Y here to get to see options related to running Linux under
507 various hypervisors. This option alone does not add any kernel code.
508
509 If you say N, all options in this submenu will be skipped and disabled.
510
511if PARAVIRT_GUEST
512
513source "arch/x86/xen/Kconfig"
514
515config VMI
d0153ca3 516 bool "VMI Guest support (DEPRECATED)"
506f1d07 517 select PARAVIRT
42d545c9 518 depends on X86_32
8f9ca475 519 ---help---
506f1d07
SR
520 VMI provides a paravirtualized interface to the VMware ESX server
521 (it could be used by other hypervisors in theory too, but is not
522 at the moment), by linking the kernel to a GPL-ed ROM module
523 provided by the hypervisor.
524
d0153ca3
AK
525 As of September 2009, VMware has started a phased retirement
526 of this feature from VMware's products. Please see
527 feature-removal-schedule.txt for details. If you are
528 planning to enable this option, please note that you cannot
529 live migrate a VMI enabled VM to a future VMware product,
530 which doesn't support VMI. So if you expect your kernel to
531 seamlessly migrate to newer VMware products, keep this
532 disabled.
533
790c73f6
GOC
534config KVM_CLOCK
535 bool "KVM paravirtualized clock"
536 select PARAVIRT
f6e16d5a 537 select PARAVIRT_CLOCK
8f9ca475 538 ---help---
790c73f6
GOC
539 Turning on this option will allow you to run a paravirtualized clock
540 when running over the KVM hypervisor. Instead of relying on a PIT
541 (or probably other) emulation by the underlying device model, the host
542 provides the guest with timing infrastructure such as time of day, and
543 system time
544
0cf1bfd2
MT
545config KVM_GUEST
546 bool "KVM Guest support"
547 select PARAVIRT
8f9ca475
IM
548 ---help---
549 This option enables various optimizations for running under the KVM
550 hypervisor.
0cf1bfd2 551
506f1d07
SR
552source "arch/x86/lguest/Kconfig"
553
e61bd94a
EPH
554config PARAVIRT
555 bool "Enable paravirtualization code"
8f9ca475 556 ---help---
e61bd94a
EPH
557 This changes the kernel so it can modify itself when it is run
558 under a hypervisor, potentially improving performance significantly
559 over full virtualization. However, when run without a hypervisor
560 the kernel is theoretically slower and slightly larger.
561
b4ecc126
JF
562config PARAVIRT_SPINLOCKS
563 bool "Paravirtualization layer for spinlocks"
564 depends on PARAVIRT && SMP && EXPERIMENTAL
565 ---help---
566 Paravirtualized spinlocks allow a pvops backend to replace the
567 spinlock implementation with something virtualization-friendly
568 (for example, block the virtual CPU rather than spinning).
569
570 Unfortunately the downside is an up to 5% performance hit on
571 native kernels, with various workloads.
572
573 If you are unsure how to answer this question, answer N.
574
7af192c9
GH
575config PARAVIRT_CLOCK
576 bool
7af192c9 577
506f1d07
SR
578endif
579
97349135 580config PARAVIRT_DEBUG
8f9ca475
IM
581 bool "paravirt-ops debugging"
582 depends on PARAVIRT && DEBUG_KERNEL
583 ---help---
584 Enable to debug paravirt_ops internals. Specifically, BUG if
585 a paravirt_op is missing when it is called.
97349135 586
08677214
YL
587config NO_BOOTMEM
588 default y
589 bool "Disable Bootmem code"
08677214
YL
590 ---help---
591 Use early_res directly instead of bootmem before slab is ready.
592 - allocator (buddy) [generic]
593 - early allocator (bootmem) [generic]
594 - very early allocator (reserve_early*()) [x86]
595 - very very early allocator (early brk model) [x86]
596 So reduce one layer between early allocator to final allocator
597
598
03273184
YL
599config MEMTEST
600 bool "Memtest"
8f9ca475 601 ---help---
c64df707 602 This option adds a kernel parameter 'memtest', which allows memtest
03273184 603 to be set.
8f9ca475
IM
604 memtest=0, mean disabled; -- default
605 memtest=1, mean do 1 test pattern;
606 ...
607 memtest=4, mean do 4 test patterns.
aba3728c 608 If you are unsure how to answer this question, answer N.
506f1d07
SR
609
610config X86_SUMMIT_NUMA
3c2362e6 611 def_bool y
e0c7ae37 612 depends on X86_32 && NUMA && X86_32_NON_STANDARD
506f1d07
SR
613
614config X86_CYCLONE_TIMER
3c2362e6 615 def_bool y
e0c7ae37 616 depends on X86_32_NON_STANDARD
506f1d07 617
506f1d07
SR
618source "arch/x86/Kconfig.cpu"
619
620config HPET_TIMER
3c2362e6 621 def_bool X86_64
506f1d07 622 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
623 ---help---
624 Use the IA-PC HPET (High Precision Event Timer) to manage
625 time in preference to the PIT and RTC, if a HPET is
626 present.
627 HPET is the next generation timer replacing legacy 8254s.
628 The HPET provides a stable time base on SMP
629 systems, unlike the TSC, but it is more expensive to access,
630 as it is off-chip. You can find the HPET spec at
631 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
506f1d07 632
8f9ca475
IM
633 You can safely choose Y here. However, HPET will only be
634 activated if the platform and the BIOS support this feature.
635 Otherwise the 8254 will be used for timing services.
506f1d07 636
8f9ca475 637 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
638
639config HPET_EMULATE_RTC
3c2362e6 640 def_bool y
9d8af78b 641 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 642
bb24c471
JP
643config APB_TIMER
644 def_bool y if MRST
645 prompt "Langwell APB Timer Support" if X86_MRST
646 help
647 APB timer is the replacement for 8254, HPET on X86 MID platforms.
648 The APBT provides a stable time base on SMP
649 systems, unlike the TSC, but it is more expensive to access,
650 as it is off-chip. APB timers are always running regardless of CPU
651 C states, they are used as per CPU clockevent device when possible.
652
506f1d07
SR
653# Mark as embedded because too many people got it wrong.
654# The code disables itself when not needed.
7ae9392c
TP
655config DMI
656 default y
657 bool "Enable DMI scanning" if EMBEDDED
8f9ca475 658 ---help---
7ae9392c
TP
659 Enabled scanning of DMI to identify machine quirks. Say Y
660 here unless you have verified that your setup is not
661 affected by entries in the DMI blacklist. Required by PNP
662 BIOS code.
663
506f1d07
SR
664config GART_IOMMU
665 bool "GART IOMMU support" if EMBEDDED
666 default y
667 select SWIOTLB
0e152cd7 668 depends on X86_64 && PCI && K8_NB
8f9ca475 669 ---help---
506f1d07
SR
670 Support for full DMA access of devices with 32bit memory access only
671 on systems with more than 3GB. This is usually needed for USB,
672 sound, many IDE/SATA chipsets and some other devices.
673 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
674 based hardware IOMMU and a software bounce buffer based IOMMU used
675 on Intel systems and as fallback.
676 The code is only active when needed (enough memory and limited
677 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
678 too.
679
680config CALGARY_IOMMU
681 bool "IBM Calgary IOMMU support"
682 select SWIOTLB
683 depends on X86_64 && PCI && EXPERIMENTAL
8f9ca475 684 ---help---
506f1d07
SR
685 Support for hardware IOMMUs in IBM's xSeries x366 and x460
686 systems. Needed to run systems with more than 3GB of memory
687 properly with 32-bit PCI devices that do not support DAC
688 (Double Address Cycle). Calgary also supports bus level
689 isolation, where all DMAs pass through the IOMMU. This
690 prevents them from going anywhere except their intended
691 destination. This catches hard-to-find kernel bugs and
692 mis-behaving drivers and devices that do not use the DMA-API
693 properly to set up their DMA buffers. The IOMMU can be
694 turned off at boot time with the iommu=off parameter.
695 Normally the kernel will make the right choice by itself.
696 If unsure, say Y.
697
698config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
699 def_bool y
700 prompt "Should Calgary be enabled by default?"
506f1d07 701 depends on CALGARY_IOMMU
8f9ca475 702 ---help---
506f1d07
SR
703 Should Calgary be enabled by default? if you choose 'y', Calgary
704 will be used (if it exists). If you choose 'n', Calgary will not be
705 used even if it exists. If you choose 'n' and would like to use
706 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
707 If unsure, say Y.
708
2b188723
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709config AMD_IOMMU
710 bool "AMD IOMMU support"
07c40e8a 711 select SWIOTLB
a80dc3e0 712 select PCI_MSI
24d2ba0a 713 depends on X86_64 && PCI && ACPI
8f9ca475 714 ---help---
18d22200
JR
715 With this option you can enable support for AMD IOMMU hardware in
716 your system. An IOMMU is a hardware component which provides
717 remapping of DMA memory accesses from devices. With an AMD IOMMU you
718 can isolate the the DMA memory of different devices and protect the
719 system from misbehaving device drivers or hardware.
720
721 You can find out if your system has an AMD IOMMU if you look into
722 your BIOS for an option to enable it or if you have an IVRS ACPI
723 table.
2b188723 724
2e117604
JR
725config AMD_IOMMU_STATS
726 bool "Export AMD IOMMU statistics to debugfs"
727 depends on AMD_IOMMU
728 select DEBUG_FS
8f9ca475 729 ---help---
2e117604
JR
730 This option enables code in the AMD IOMMU driver to collect various
731 statistics about whats happening in the driver and exports that
732 information to userspace via debugfs.
733 If unsure, say N.
734
506f1d07
SR
735# need this always selected by IOMMU for the VIA workaround
736config SWIOTLB
a1afd01c 737 def_bool y if X86_64
8f9ca475 738 ---help---
506f1d07
SR
739 Support for software bounce buffers used on x86-64 systems
740 which don't have a hardware IOMMU (e.g. the current generation
741 of Intel's x86-64 CPUs). Using this PCI devices which can only
742 access 32-bits of memory can be used on systems with more than
743 3 GB of memory. If unsure, say Y.
744
a8522509 745config IOMMU_HELPER
18b743dc 746 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
d25e26b6 747
1aaf1183
JR
748config IOMMU_API
749 def_bool (AMD_IOMMU || DMAR)
750
1184dc2f
MT
751config MAXSMP
752 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
36f5101a
MT
753 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
754 select CPUMASK_OFFSTACK
8f9ca475 755 ---help---
1184dc2f
MT
756 Configure maximum number of CPUS and NUMA Nodes for this architecture.
757 If unsure, say N.
506f1d07
SR
758
759config NR_CPUS
36f5101a 760 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 761 range 2 8 if SMP && X86_32 && !X86_BIGSMP
36f5101a 762 range 2 512 if SMP && !MAXSMP
78637a97 763 default "1" if !SMP
d25e26b6 764 default "4096" if MAXSMP
78637a97
MT
765 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
766 default "8" if SMP
8f9ca475 767 ---help---
506f1d07 768 This allows you to specify the maximum number of CPUs which this
d25e26b6 769 kernel will support. The maximum supported value is 512 and the
506f1d07
SR
770 minimum value which makes sense is 2.
771
772 This is purely to save memory - each supported CPU adds
773 approximately eight kilobytes to the kernel image.
774
775config SCHED_SMT
776 bool "SMT (Hyperthreading) scheduler support"
b089c12b 777 depends on X86_HT
8f9ca475 778 ---help---
506f1d07
SR
779 SMT scheduler support improves the CPU scheduler's decision making
780 when dealing with Intel Pentium 4 chips with HyperThreading at a
781 cost of slightly increased overhead in some places. If unsure say
782 N here.
783
784config SCHED_MC
3c2362e6
HH
785 def_bool y
786 prompt "Multi-core scheduler support"
b089c12b 787 depends on X86_HT
8f9ca475 788 ---help---
506f1d07
SR
789 Multi-core scheduler support improves the CPU scheduler's decision
790 making when dealing with multi-core CPU chips at a cost of slightly
791 increased overhead in some places. If unsure say N here.
792
793source "kernel/Kconfig.preempt"
794
795config X86_UP_APIC
796 bool "Local APIC support on uniprocessors"
e0c7ae37 797 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 798 ---help---
506f1d07
SR
799 A local APIC (Advanced Programmable Interrupt Controller) is an
800 integrated interrupt controller in the CPU. If you have a single-CPU
801 system which has a processor with a local APIC, you can say Y here to
802 enable and use it. If you say Y here even though your machine doesn't
803 have a local APIC, then the kernel will still run with no slowdown at
804 all. The local APIC supports CPU-generated self-interrupts (timer,
805 performance counters), and the NMI watchdog which detects hard
806 lockups.
807
808config X86_UP_IOAPIC
809 bool "IO-APIC support on uniprocessors"
810 depends on X86_UP_APIC
8f9ca475 811 ---help---
506f1d07
SR
812 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
813 SMP-capable replacement for PC-style interrupt controllers. Most
814 SMP systems and many recent uniprocessor systems have one.
815
816 If you have a single-CPU system with an IO-APIC, you can say Y here
817 to use it. If you say Y here even though your machine doesn't have
818 an IO-APIC, then the kernel will still run with no slowdown at all.
819
820config X86_LOCAL_APIC
3c2362e6 821 def_bool y
e0c7ae37 822 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
823
824config X86_IO_APIC
3c2362e6 825 def_bool y
e0c7ae37 826 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
827
828config X86_VISWS_APIC
3c2362e6 829 def_bool y
506f1d07 830 depends on X86_32 && X86_VISWS
506f1d07 831
41b9eb26
SA
832config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
833 bool "Reroute for broken boot IRQs"
41b9eb26 834 depends on X86_IO_APIC
8f9ca475 835 ---help---
41b9eb26
SA
836 This option enables a workaround that fixes a source of
837 spurious interrupts. This is recommended when threaded
838 interrupt handling is used on systems where the generation of
839 superfluous "boot interrupts" cannot be disabled.
840
841 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
842 entry in the chipset's IO-APIC is masked (as, e.g. the RT
843 kernel does during interrupt handling). On chipsets where this
844 boot IRQ generation cannot be disabled, this workaround keeps
845 the original IRQ line masked so that only the equivalent "boot
846 IRQ" is delivered to the CPUs. The workaround also tells the
847 kernel to set up the IRQ handler on the boot IRQ line. In this
848 way only one interrupt is delivered to the kernel. Otherwise
849 the spurious second interrupt may cause the kernel to bring
850 down (vital) interrupt lines.
851
852 Only affects "broken" chipsets. Interrupt sharing may be
853 increased on these systems.
854
506f1d07 855config X86_MCE
bab9bc65 856 bool "Machine Check / overheating reporting"
506f1d07 857 ---help---
bab9bc65
AK
858 Machine Check support allows the processor to notify the
859 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 860 The action the kernel takes depends on the severity of the problem,
bab9bc65 861 ranging from warning messages to halting the machine.
4efc0670 862
506f1d07 863config X86_MCE_INTEL
3c2362e6
HH
864 def_bool y
865 prompt "Intel MCE features"
c1ebf835 866 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 867 ---help---
506f1d07
SR
868 Additional support for intel specific MCE features such as
869 the thermal monitor.
870
871config X86_MCE_AMD
3c2362e6
HH
872 def_bool y
873 prompt "AMD MCE features"
c1ebf835 874 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 875 ---help---
506f1d07
SR
876 Additional support for AMD specific MCE features such as
877 the DRAM Error Threshold.
878
4efc0670 879config X86_ANCIENT_MCE
6fc108a0 880 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 881 depends on X86_32 && X86_MCE
cd13adcc
HS
882 ---help---
883 Include support for machine check handling on old Pentium 5 or WinChip
884 systems. These typically need to be enabled explicitely on the command
885 line.
4efc0670 886
b2762686
AK
887config X86_MCE_THRESHOLD
888 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 889 def_bool y
b2762686 890
ea149b36 891config X86_MCE_INJECT
c1ebf835 892 depends on X86_MCE
ea149b36
AK
893 tristate "Machine check injector support"
894 ---help---
895 Provide support for injecting machine checks for testing purposes.
896 If you don't know what a machine check is and you don't do kernel
897 QA it is safe to say n.
898
4efc0670
AK
899config X86_THERMAL_VECTOR
900 def_bool y
5bb38adc 901 depends on X86_MCE_INTEL
4efc0670 902
506f1d07
SR
903config VM86
904 bool "Enable VM86 support" if EMBEDDED
905 default y
906 depends on X86_32
8f9ca475
IM
907 ---help---
908 This option is required by programs like DOSEMU to run 16-bit legacy
506f1d07 909 code on X86 processors. It also may be needed by software like
8f9ca475
IM
910 XFree86 to initialize some video cards via BIOS. Disabling this
911 option saves about 6k.
506f1d07
SR
912
913config TOSHIBA
914 tristate "Toshiba Laptop support"
915 depends on X86_32
916 ---help---
917 This adds a driver to safely access the System Management Mode of
918 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
919 not work on models with a Phoenix BIOS. The System Management Mode
920 is used to set the BIOS and power saving options on Toshiba portables.
921
922 For information on utilities to make use of this driver see the
923 Toshiba Linux utilities web site at:
924 <http://www.buzzard.org.uk/toshiba/>.
925
926 Say Y if you intend to run this kernel on a Toshiba portable.
927 Say N otherwise.
928
929config I8K
930 tristate "Dell laptop support"
506f1d07
SR
931 ---help---
932 This adds a driver to safely access the System Management Mode
933 of the CPU on the Dell Inspiron 8000. The System Management Mode
934 is used to read cpu temperature and cooling fan status and to
935 control the fans on the I8K portables.
936
937 This driver has been tested only on the Inspiron 8000 but it may
938 also work with other Dell laptops. You can force loading on other
939 models by passing the parameter `force=1' to the module. Use at
940 your own risk.
941
942 For information on utilities to make use of this driver see the
943 I8K Linux utilities web site at:
944 <http://people.debian.org/~dz/i8k/>
945
946 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
947 Say N otherwise.
948
949config X86_REBOOTFIXUPS
9ba16087
JB
950 bool "Enable X86 board specific fixups for reboot"
951 depends on X86_32
506f1d07
SR
952 ---help---
953 This enables chipset and/or board specific fixups to be done
954 in order to get reboot to work correctly. This is only needed on
955 some combinations of hardware and BIOS. The symptom, for which
956 this config is intended, is when reboot ends with a stalled/hung
957 system.
958
959 Currently, the only fixup is for the Geode machines using
5e3a77e9 960 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
961
962 Say Y if you want to enable the fixup. Currently, it's safe to
963 enable this option even if you don't need it.
964 Say N otherwise.
965
966config MICROCODE
8d86f390 967 tristate "/dev/cpu/microcode - microcode support"
506f1d07
SR
968 select FW_LOADER
969 ---help---
970 If you say Y here, you will be able to update the microcode on
80cc9f10
PO
971 certain Intel and AMD processors. The Intel support is for the
972 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
973 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
974 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
975 You will obviously need the actual microcode binary data itself
976 which is not shipped with the Linux kernel.
506f1d07 977
8d86f390
PO
978 This option selects the general module only, you need to select
979 at least one vendor specific module as well.
506f1d07
SR
980
981 To compile this driver as a module, choose M here: the
982 module will be called microcode.
983
8d86f390 984config MICROCODE_INTEL
8f9ca475
IM
985 bool "Intel microcode patch loading support"
986 depends on MICROCODE
987 default MICROCODE
988 select FW_LOADER
989 ---help---
990 This options enables microcode patch loading support for Intel
991 processors.
992
993 For latest news and information on obtaining all the required
994 Intel ingredients for this driver, check:
995 <http://www.urbanmyth.org/microcode/>.
8d86f390 996
80cc9f10 997config MICROCODE_AMD
8f9ca475
IM
998 bool "AMD microcode patch loading support"
999 depends on MICROCODE
1000 select FW_LOADER
1001 ---help---
1002 If you select this option, microcode patch loading support for AMD
1003 processors will be enabled.
80cc9f10 1004
8f9ca475 1005config MICROCODE_OLD_INTERFACE
3c2362e6 1006 def_bool y
506f1d07 1007 depends on MICROCODE
506f1d07
SR
1008
1009config X86_MSR
1010 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1011 ---help---
506f1d07
SR
1012 This device gives privileged processes access to the x86
1013 Model-Specific Registers (MSRs). It is a character device with
1014 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1015 MSR accesses are directed to a specific CPU on multi-processor
1016 systems.
1017
1018config X86_CPUID
1019 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1020 ---help---
506f1d07
SR
1021 This device gives processes access to the x86 CPUID instruction to
1022 be executed on a specific processor. It is a character device
1023 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1024 /dev/cpu/31/cpuid.
1025
1026choice
1027 prompt "High Memory Support"
506f1d07 1028 default HIGHMEM64G if X86_NUMAQ
6fc108a0 1029 default HIGHMEM4G
506f1d07
SR
1030 depends on X86_32
1031
1032config NOHIGHMEM
1033 bool "off"
1034 depends on !X86_NUMAQ
1035 ---help---
1036 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1037 However, the address space of 32-bit x86 processors is only 4
1038 Gigabytes large. That means that, if you have a large amount of
1039 physical memory, not all of it can be "permanently mapped" by the
1040 kernel. The physical memory that's not permanently mapped is called
1041 "high memory".
1042
1043 If you are compiling a kernel which will never run on a machine with
1044 more than 1 Gigabyte total physical RAM, answer "off" here (default
1045 choice and suitable for most users). This will result in a "3GB/1GB"
1046 split: 3GB are mapped so that each process sees a 3GB virtual memory
1047 space and the remaining part of the 4GB virtual memory space is used
1048 by the kernel to permanently map as much physical memory as
1049 possible.
1050
1051 If the machine has between 1 and 4 Gigabytes physical RAM, then
1052 answer "4GB" here.
1053
1054 If more than 4 Gigabytes is used then answer "64GB" here. This
1055 selection turns Intel PAE (Physical Address Extension) mode on.
1056 PAE implements 3-level paging on IA32 processors. PAE is fully
1057 supported by Linux, PAE mode is implemented on all recent Intel
1058 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1059 then the kernel will not boot on CPUs that don't support PAE!
1060
1061 The actual amount of total physical memory will either be
1062 auto detected or can be forced by using a kernel command line option
1063 such as "mem=256M". (Try "man bootparam" or see the documentation of
1064 your boot loader (lilo or loadlin) about how to pass options to the
1065 kernel at boot time.)
1066
1067 If unsure, say "off".
1068
1069config HIGHMEM4G
1070 bool "4GB"
1071 depends on !X86_NUMAQ
8f9ca475 1072 ---help---
506f1d07
SR
1073 Select this if you have a 32-bit processor and between 1 and 4
1074 gigabytes of physical RAM.
1075
1076config HIGHMEM64G
1077 bool "64GB"
1078 depends on !M386 && !M486
1079 select X86_PAE
8f9ca475 1080 ---help---
506f1d07
SR
1081 Select this if you have a 32-bit processor and more than 4
1082 gigabytes of physical RAM.
1083
1084endchoice
1085
1086choice
1087 depends on EXPERIMENTAL
1088 prompt "Memory split" if EMBEDDED
1089 default VMSPLIT_3G
1090 depends on X86_32
8f9ca475 1091 ---help---
506f1d07
SR
1092 Select the desired split between kernel and user memory.
1093
1094 If the address range available to the kernel is less than the
1095 physical memory installed, the remaining memory will be available
1096 as "high memory". Accessing high memory is a little more costly
1097 than low memory, as it needs to be mapped into the kernel first.
1098 Note that increasing the kernel address space limits the range
1099 available to user programs, making the address space there
1100 tighter. Selecting anything other than the default 3G/1G split
1101 will also likely make your kernel incompatible with binary-only
1102 kernel modules.
1103
1104 If you are not absolutely sure what you are doing, leave this
1105 option alone!
1106
1107 config VMSPLIT_3G
1108 bool "3G/1G user/kernel split"
1109 config VMSPLIT_3G_OPT
1110 depends on !X86_PAE
1111 bool "3G/1G user/kernel split (for full 1G low memory)"
1112 config VMSPLIT_2G
1113 bool "2G/2G user/kernel split"
1114 config VMSPLIT_2G_OPT
1115 depends on !X86_PAE
1116 bool "2G/2G user/kernel split (for full 2G low memory)"
1117 config VMSPLIT_1G
1118 bool "1G/3G user/kernel split"
1119endchoice
1120
1121config PAGE_OFFSET
1122 hex
1123 default 0xB0000000 if VMSPLIT_3G_OPT
1124 default 0x80000000 if VMSPLIT_2G
1125 default 0x78000000 if VMSPLIT_2G_OPT
1126 default 0x40000000 if VMSPLIT_1G
1127 default 0xC0000000
1128 depends on X86_32
1129
1130config HIGHMEM
3c2362e6 1131 def_bool y
506f1d07 1132 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1133
1134config X86_PAE
9ba16087 1135 bool "PAE (Physical Address Extension) Support"
506f1d07 1136 depends on X86_32 && !HIGHMEM4G
8f9ca475 1137 ---help---
506f1d07
SR
1138 PAE is required for NX support, and furthermore enables
1139 larger swapspace support for non-overcommit purposes. It
1140 has the cost of more pagetable lookup overhead, and also
1141 consumes more pagetable space per process.
1142
600715dc 1143config ARCH_PHYS_ADDR_T_64BIT
8f9ca475 1144 def_bool X86_64 || X86_PAE
600715dc 1145
9e899816
NP
1146config DIRECT_GBPAGES
1147 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1148 default y
1149 depends on X86_64
8f9ca475 1150 ---help---
9e899816
NP
1151 Allow the kernel linear mapping to use 1GB pages on CPUs that
1152 support it. This can improve the kernel's performance a tiny bit by
1153 reducing TLB pressure. If in doubt, say "Y".
1154
506f1d07
SR
1155# Common NUMA Features
1156config NUMA
fd51b2d7 1157 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1158 depends on SMP
604d2055 1159 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
0699eae1 1160 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
8f9ca475 1161 ---help---
506f1d07 1162 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1163
506f1d07
SR
1164 The kernel will try to allocate memory used by a CPU on the
1165 local memory controller of the CPU and add some more
1166 NUMA awareness to the kernel.
1167
c280ea5e 1168 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1169 (or later), AMD Opteron, or EM64T NUMA.
1170
1171 For 32-bit this is only needed on (rare) 32-bit-only platforms
1172 that support NUMA topologies, such as NUMAQ / Summit, or if you
1173 boot a 32-bit kernel on a 64-bit NUMA platform.
1174
1175 Otherwise, you should say N.
506f1d07
SR
1176
1177comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1178 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1179
1180config K8_NUMA
3c2362e6
HH
1181 def_bool y
1182 prompt "Old style AMD Opteron NUMA detection"
1183 depends on X86_64 && NUMA && PCI
8f9ca475
IM
1184 ---help---
1185 Enable K8 NUMA node topology detection. You should say Y here if
1186 you have a multi processor AMD K8 system. This uses an old
1187 method to read the NUMA configuration directly from the builtin
1188 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1189 instead, which also takes priority if both are compiled in.
506f1d07
SR
1190
1191config X86_64_ACPI_NUMA
3c2362e6
HH
1192 def_bool y
1193 prompt "ACPI NUMA detection"
506f1d07
SR
1194 depends on X86_64 && NUMA && ACPI && PCI
1195 select ACPI_NUMA
8f9ca475 1196 ---help---
506f1d07
SR
1197 Enable ACPI SRAT based node topology detection.
1198
6ec6e0d9
SS
1199# Some NUMA nodes have memory ranges that span
1200# other nodes. Even though a pfn is valid and
1201# between a node's start and end pfns, it may not
1202# reside on that node. See memmap_init_zone()
1203# for details.
1204config NODES_SPAN_OTHER_NODES
1205 def_bool y
1206 depends on X86_64_ACPI_NUMA
1207
506f1d07
SR
1208config NUMA_EMU
1209 bool "NUMA emulation"
1210 depends on X86_64 && NUMA
8f9ca475 1211 ---help---
506f1d07
SR
1212 Enable NUMA emulation. A flat machine will be split
1213 into virtual nodes when booted with "numa=fake=N", where N is the
1214 number of nodes. This is only useful for debugging.
1215
1216config NODES_SHIFT
d25e26b6 1217 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1218 range 1 10
1219 default "10" if MAXSMP
506f1d07
SR
1220 default "6" if X86_64
1221 default "4" if X86_NUMAQ
1222 default "3"
1223 depends on NEED_MULTIPLE_NODES
8f9ca475 1224 ---help---
1184dc2f 1225 Specify the maximum number of NUMA Nodes available on the target
692105b8 1226 system. Increases memory reserved to accommodate various tables.
506f1d07 1227
c1329375 1228config HAVE_ARCH_BOOTMEM
3c2362e6 1229 def_bool y
506f1d07 1230 depends on X86_32 && NUMA
506f1d07
SR
1231
1232config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1233 def_bool y
506f1d07 1234 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1235
1236config NEED_NODE_MEMMAP_SIZE
3c2362e6 1237 def_bool y
506f1d07 1238 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07
SR
1239
1240config HAVE_ARCH_ALLOC_REMAP
3c2362e6 1241 def_bool y
506f1d07 1242 depends on X86_32 && NUMA
506f1d07
SR
1243
1244config ARCH_FLATMEM_ENABLE
1245 def_bool y
99809963 1246 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
506f1d07
SR
1247
1248config ARCH_DISCONTIGMEM_ENABLE
1249 def_bool y
b263295d 1250 depends on NUMA && X86_32
506f1d07
SR
1251
1252config ARCH_DISCONTIGMEM_DEFAULT
1253 def_bool y
b263295d
CL
1254 depends on NUMA && X86_32
1255
9492587c
KH
1256config ARCH_PROC_KCORE_TEXT
1257 def_bool y
1258 depends on X86_64 && PROC_KCORE
1259
b263295d
CL
1260config ARCH_SPARSEMEM_DEFAULT
1261 def_bool y
1262 depends on X86_64
506f1d07
SR
1263
1264config ARCH_SPARSEMEM_ENABLE
1265 def_bool y
4272ebfb 1266 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
506f1d07
SR
1267 select SPARSEMEM_STATIC if X86_32
1268 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1269
1270config ARCH_SELECT_MEMORY_MODEL
1271 def_bool y
b263295d 1272 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1273
1274config ARCH_MEMORY_PROBE
1275 def_bool X86_64
1276 depends on MEMORY_HOTPLUG
1277
a29815a3
AK
1278config ILLEGAL_POINTER_VALUE
1279 hex
1280 default 0 if X86_32
1281 default 0xdead000000000000 if X86_64
1282
506f1d07
SR
1283source "mm/Kconfig"
1284
1285config HIGHPTE
1286 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1287 depends on HIGHMEM
8f9ca475 1288 ---help---
506f1d07
SR
1289 The VM uses one page table entry for each page of physical memory.
1290 For systems with a lot of RAM, this can be wasteful of precious
1291 low memory. Setting this option will put user-space page table
1292 entries in high memory.
1293
9f077871 1294config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1295 bool "Check for low memory corruption"
1296 ---help---
1297 Periodically check for memory corruption in low memory, which
1298 is suspected to be caused by BIOS. Even when enabled in the
1299 configuration, it is disabled at runtime. Enable it by
1300 setting "memory_corruption_check=1" on the kernel command
1301 line. By default it scans the low 64k of memory every 60
1302 seconds; see the memory_corruption_check_size and
1303 memory_corruption_check_period parameters in
1304 Documentation/kernel-parameters.txt to adjust this.
1305
1306 When enabled with the default parameters, this option has
1307 almost no overhead, as it reserves a relatively small amount
1308 of memory and scans it infrequently. It both detects corruption
1309 and prevents it from affecting the running system.
1310
1311 It is, however, intended as a diagnostic tool; if repeatable
1312 BIOS-originated corruption always affects the same memory,
1313 you can use memmap= to prevent the kernel from using that
1314 memory.
9f077871 1315
c885df50 1316config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1317 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1318 depends on X86_CHECK_BIOS_CORRUPTION
1319 default y
8f9ca475
IM
1320 ---help---
1321 Set whether the default state of memory_corruption_check is
1322 on or off.
c885df50 1323
fc381519 1324config X86_RESERVE_LOW_64K
8f9ca475 1325 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
fc381519 1326 default y
8f9ca475
IM
1327 ---help---
1328 Reserve the first 64K of physical RAM on BIOSes that are known
1329 to potentially corrupt that memory range. A numbers of BIOSes are
1330 known to utilize this area during suspend/resume, so it must not
1331 be used by the kernel.
fc381519 1332
8f9ca475
IM
1333 Set this to N if you are absolutely sure that you trust the BIOS
1334 to get all its memory reservations and usages right.
fc381519 1335
8f9ca475
IM
1336 If you have doubts about the BIOS (e.g. suspend/resume does not
1337 work or there's kernel crashes after certain hardware hotplug
1338 events) and it's not AMI or Phoenix, then you might want to enable
1339 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1340 corruption patterns.
fc381519 1341
8f9ca475 1342 Say Y if unsure.
fc381519 1343
506f1d07
SR
1344config MATH_EMULATION
1345 bool
1346 prompt "Math emulation" if X86_32
1347 ---help---
1348 Linux can emulate a math coprocessor (used for floating point
1349 operations) if you don't have one. 486DX and Pentium processors have
1350 a math coprocessor built in, 486SX and 386 do not, unless you added
1351 a 487DX or 387, respectively. (The messages during boot time can
1352 give you some hints here ["man dmesg"].) Everyone needs either a
1353 coprocessor or this emulation.
1354
1355 If you don't have a math coprocessor, you need to say Y here; if you
1356 say Y here even though you have a coprocessor, the coprocessor will
1357 be used nevertheless. (This behavior can be changed with the kernel
1358 command line option "no387", which comes handy if your coprocessor
1359 is broken. Try "man bootparam" or see the documentation of your boot
1360 loader (lilo or loadlin) about how to pass options to the kernel at
1361 boot time.) This means that it is a good idea to say Y here if you
1362 intend to use this kernel on different machines.
1363
1364 More information about the internals of the Linux math coprocessor
1365 emulation can be found in <file:arch/x86/math-emu/README>.
1366
1367 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1368 kernel, it won't hurt.
1369
1370config MTRR
6fc108a0 1371 def_bool y
c03cb314 1372 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
506f1d07
SR
1373 ---help---
1374 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1375 the Memory Type Range Registers (MTRRs) may be used to control
1376 processor access to memory ranges. This is most useful if you have
1377 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1378 allows bus write transfers to be combined into a larger transfer
1379 before bursting over the PCI/AGP bus. This can increase performance
1380 of image write operations 2.5 times or more. Saying Y here creates a
1381 /proc/mtrr file which may be used to manipulate your processor's
1382 MTRRs. Typically the X server should use this.
1383
1384 This code has a reasonably generic interface so that similar
1385 control registers on other processors can be easily supported
1386 as well:
1387
1388 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1389 Registers (ARRs) which provide a similar functionality to MTRRs. For
1390 these, the ARRs are used to emulate the MTRRs.
1391 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1392 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1393 write-combining. All of these processors are supported by this code
1394 and it makes sense to say Y here if you have one of them.
1395
1396 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1397 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1398 can lead to all sorts of problems, so it's good to say Y here.
1399
1400 You can safely say Y even if your machine doesn't have MTRRs, you'll
1401 just add about 9 KB to your kernel.
1402
7225e751 1403 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1404
95ffa243 1405config MTRR_SANITIZER
2ffb3501 1406 def_bool y
95ffa243
YL
1407 prompt "MTRR cleanup support"
1408 depends on MTRR
8f9ca475 1409 ---help---
aba3728c
TG
1410 Convert MTRR layout from continuous to discrete, so X drivers can
1411 add writeback entries.
95ffa243 1412
aba3728c 1413 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1414 The largest mtrr entry size for a continuous block can be set with
aba3728c 1415 mtrr_chunk_size.
95ffa243 1416
2ffb3501 1417 If unsure, say Y.
95ffa243
YL
1418
1419config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1420 int "MTRR cleanup enable value (0-1)"
1421 range 0 1
1422 default "0"
95ffa243 1423 depends on MTRR_SANITIZER
8f9ca475 1424 ---help---
f5098d62 1425 Enable mtrr cleanup default value
95ffa243 1426
12031a62
YL
1427config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1428 int "MTRR cleanup spare reg num (0-7)"
1429 range 0 7
1430 default "1"
1431 depends on MTRR_SANITIZER
8f9ca475 1432 ---help---
12031a62 1433 mtrr cleanup spare entries default, it can be changed via
aba3728c 1434 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1435
2e5d9c85 1436config X86_PAT
6fc108a0 1437 def_bool y
c03cb314 1438 prompt "x86 PAT support" if EMBEDDED
2a8a2719 1439 depends on MTRR
8f9ca475 1440 ---help---
2e5d9c85 1441 Use PAT attributes to setup page level cache control.
042b78e4 1442
2e5d9c85 1443 PATs are the modern equivalents of MTRRs and are much more
1444 flexible than MTRRs.
1445
1446 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1447 spontaneous reboots) or a non-working video driver.
2e5d9c85 1448
1449 If unsure, say Y.
1450
46cf98cd
VP
1451config ARCH_USES_PG_UNCACHED
1452 def_bool y
1453 depends on X86_PAT
1454
506f1d07 1455config EFI
9ba16087 1456 bool "EFI runtime service support"
5b83683f 1457 depends on ACPI
506f1d07 1458 ---help---
8f9ca475
IM
1459 This enables the kernel to use EFI runtime services that are
1460 available (such as the EFI variable services).
506f1d07 1461
8f9ca475
IM
1462 This option is only useful on systems that have EFI firmware.
1463 In addition, you should use the latest ELILO loader available
1464 at <http://elilo.sourceforge.net> in order to take advantage
1465 of EFI runtime services. However, even with this option, the
1466 resultant kernel should continue to boot on existing non-EFI
1467 platforms.
506f1d07 1468
506f1d07 1469config SECCOMP
3c2362e6
HH
1470 def_bool y
1471 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1472 ---help---
506f1d07
SR
1473 This kernel feature is useful for number crunching applications
1474 that may need to compute untrusted bytecode during their
1475 execution. By using pipes or other transports made available to
1476 the process as file descriptors supporting the read/write
1477 syscalls, it's possible to isolate those applications in
1478 their own address space using seccomp. Once seccomp is
9c0bbee8 1479 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1480 and the task is only allowed to execute a few safe syscalls
1481 defined by each seccomp mode.
1482
1483 If unsure, say Y. Only embedded should say N here.
1484
1485config CC_STACKPROTECTOR
1486 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
8f9ca475
IM
1487 ---help---
1488 This option turns on the -fstack-protector GCC feature. This
113c5413
IM
1489 feature puts, at the beginning of functions, a canary value on
1490 the stack just before the return address, and validates
506f1d07
SR
1491 the value just before actually returning. Stack based buffer
1492 overflows (that need to overwrite this return address) now also
1493 overwrite the canary, which gets detected and the attack is then
1494 neutralized via a kernel panic.
1495
1496 This feature requires gcc version 4.2 or above, or a distribution
1497 gcc with the feature backported. Older versions are automatically
113c5413
IM
1498 detected and for those versions, this configuration option is
1499 ignored. (and a warning is printed during bootup)
506f1d07
SR
1500
1501source kernel/Kconfig.hz
1502
1503config KEXEC
1504 bool "kexec system call"
8f9ca475 1505 ---help---
506f1d07
SR
1506 kexec is a system call that implements the ability to shutdown your
1507 current kernel, and to start another kernel. It is like a reboot
1508 but it is independent of the system firmware. And like a reboot
1509 you can start any kernel with it, not just Linux.
1510
1511 The name comes from the similarity to the exec system call.
1512
1513 It is an ongoing process to be certain the hardware in a machine
1514 is properly shutdown, so do not be surprised if this code does not
1515 initially work for you. It may help to enable device hotplugging
1516 support. As of this writing the exact hardware interface is
1517 strongly in flux, so no good recommendation can be made.
1518
1519config CRASH_DUMP
04b69447 1520 bool "kernel crash dumps"
506f1d07 1521 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1522 ---help---
506f1d07
SR
1523 Generate crash dump after being started by kexec.
1524 This should be normally only set in special crash dump kernels
1525 which are loaded in the main kernel with kexec-tools into
1526 a specially reserved region and then later executed after
1527 a crash by kdump/kexec. The crash dump kernel must be compiled
1528 to a memory address not used by the main kernel or BIOS using
1529 PHYSICAL_START, or it must be built as a relocatable image
1530 (CONFIG_RELOCATABLE=y).
1531 For more details see Documentation/kdump/kdump.txt
1532
3ab83521
HY
1533config KEXEC_JUMP
1534 bool "kexec jump (EXPERIMENTAL)"
1535 depends on EXPERIMENTAL
fee7b0d8 1536 depends on KEXEC && HIBERNATION
8f9ca475 1537 ---help---
89081d17
HY
1538 Jump between original kernel and kexeced kernel and invoke
1539 code in physical address mode via KEXEC
3ab83521 1540
506f1d07
SR
1541config PHYSICAL_START
1542 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
ceefccc9 1543 default "0x1000000"
8f9ca475 1544 ---help---
506f1d07
SR
1545 This gives the physical address where the kernel is loaded.
1546
1547 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1548 bzImage will decompress itself to above physical address and
1549 run from there. Otherwise, bzImage will run from the address where
1550 it has been loaded by the boot loader and will ignore above physical
1551 address.
1552
1553 In normal kdump cases one does not have to set/change this option
1554 as now bzImage can be compiled as a completely relocatable image
1555 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1556 address. This option is mainly useful for the folks who don't want
1557 to use a bzImage for capturing the crash dump and want to use a
1558 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1559 to be specifically compiled to run from a specific memory area
1560 (normally a reserved region) and this option comes handy.
1561
ceefccc9
PA
1562 So if you are using bzImage for capturing the crash dump,
1563 leave the value here unchanged to 0x1000000 and set
1564 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1565 for capturing the crash dump change this value to start of
1566 the reserved region. In other words, it can be set based on
1567 the "X" value as specified in the "crashkernel=YM@XM"
1568 command line boot parameter passed to the panic-ed
1569 kernel. Please take a look at Documentation/kdump/kdump.txt
1570 for more details about crash dumps.
506f1d07
SR
1571
1572 Usage of bzImage for capturing the crash dump is recommended as
1573 one does not have to build two kernels. Same kernel can be used
1574 as production kernel and capture kernel. Above option should have
1575 gone away after relocatable bzImage support is introduced. But it
1576 is present because there are users out there who continue to use
1577 vmlinux for dump capture. This option should go away down the
1578 line.
1579
1580 Don't change this unless you know what you are doing.
1581
1582config RELOCATABLE
26717808
PA
1583 bool "Build a relocatable kernel"
1584 default y
8f9ca475 1585 ---help---
506f1d07
SR
1586 This builds a kernel image that retains relocation information
1587 so it can be loaded someplace besides the default 1MB.
1588 The relocations tend to make the kernel binary about 10% larger,
1589 but are discarded at runtime.
1590
1591 One use is for the kexec on panic case where the recovery kernel
1592 must live at a different physical address than the primary
1593 kernel.
1594
1595 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1596 it has been loaded at and the compile time physical address
1597 (CONFIG_PHYSICAL_START) is ignored.
1598
845adf72
PA
1599# Relocation on x86-32 needs some additional build support
1600config X86_NEED_RELOCS
1601 def_bool y
1602 depends on X86_32 && RELOCATABLE
1603
506f1d07 1604config PHYSICAL_ALIGN
6fc108a0 1605 hex "Alignment value to which kernel should be aligned" if X86_32
ceefccc9
PA
1606 default "0x1000000"
1607 range 0x2000 0x1000000
8f9ca475 1608 ---help---
506f1d07
SR
1609 This value puts the alignment restrictions on physical address
1610 where kernel is loaded and run from. Kernel is compiled for an
1611 address which meets above alignment restriction.
1612
1613 If bootloader loads the kernel at a non-aligned address and
1614 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1615 address aligned to above value and run from there.
1616
1617 If bootloader loads the kernel at a non-aligned address and
1618 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1619 load address and decompress itself to the address it has been
1620 compiled for and run from there. The address for which kernel is
1621 compiled already meets above alignment restrictions. Hence the
1622 end result is that kernel runs from a physical address meeting
1623 above alignment restrictions.
1624
1625 Don't change this unless you know what you are doing.
1626
1627config HOTPLUG_CPU
7c13e6a3 1628 bool "Support for hot-pluggable CPUs"
4b19ed91 1629 depends on SMP && HOTPLUG
506f1d07 1630 ---help---
7c13e6a3
DS
1631 Say Y here to allow turning CPUs off and on. CPUs can be
1632 controlled through /sys/devices/system/cpu.
1633 ( Note: power management support will enable this option
1634 automatically on SMP systems. )
1635 Say N if you want to disable CPU hotplug.
506f1d07
SR
1636
1637config COMPAT_VDSO
3c2362e6
HH
1638 def_bool y
1639 prompt "Compat VDSO support"
af65d648 1640 depends on X86_32 || IA32_EMULATION
8f9ca475 1641 ---help---
af65d648 1642 Map the 32-bit VDSO to the predictable old-style address too.
e84446de 1643
506f1d07
SR
1644 Say N here if you are running a sufficiently recent glibc
1645 version (2.3.3 or later), to remove the high-mapped
1646 VDSO mapping and to exclusively use the randomized VDSO.
1647
1648 If unsure, say Y.
1649
516cbf37
TB
1650config CMDLINE_BOOL
1651 bool "Built-in kernel command line"
8f9ca475 1652 ---help---
516cbf37
TB
1653 Allow for specifying boot arguments to the kernel at
1654 build time. On some systems (e.g. embedded ones), it is
1655 necessary or convenient to provide some or all of the
1656 kernel boot arguments with the kernel itself (that is,
1657 to not rely on the boot loader to provide them.)
1658
1659 To compile command line arguments into the kernel,
1660 set this option to 'Y', then fill in the
1661 the boot arguments in CONFIG_CMDLINE.
1662
1663 Systems with fully functional boot loaders (i.e. non-embedded)
1664 should leave this option set to 'N'.
1665
1666config CMDLINE
1667 string "Built-in kernel command string"
1668 depends on CMDLINE_BOOL
1669 default ""
8f9ca475 1670 ---help---
516cbf37
TB
1671 Enter arguments here that should be compiled into the kernel
1672 image and used at boot time. If the boot loader provides a
1673 command line at boot time, it is appended to this string to
1674 form the full kernel command line, when the system boots.
1675
1676 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1677 change this behavior.
1678
1679 In most cases, the command line (whether built-in or provided
1680 by the boot loader) should specify the device for the root
1681 file system.
1682
1683config CMDLINE_OVERRIDE
1684 bool "Built-in command line overrides boot loader arguments"
516cbf37 1685 depends on CMDLINE_BOOL
8f9ca475 1686 ---help---
516cbf37
TB
1687 Set this option to 'Y' to have the kernel ignore the boot loader
1688 command line, and use ONLY the built-in command line.
1689
1690 This is used to work around broken boot loaders. This should
1691 be set to 'N' under normal conditions.
1692
506f1d07
SR
1693endmenu
1694
1695config ARCH_ENABLE_MEMORY_HOTPLUG
1696 def_bool y
1697 depends on X86_64 || (X86_32 && HIGHMEM)
1698
35551053
GH
1699config ARCH_ENABLE_MEMORY_HOTREMOVE
1700 def_bool y
1701 depends on MEMORY_HOTPLUG
1702
506f1d07
SR
1703config HAVE_ARCH_EARLY_PFN_TO_NID
1704 def_bool X86_64
1705 depends on NUMA
1706
e534c7c5
LS
1707config USE_PERCPU_NUMA_NODE_ID
1708 def_bool X86_64
1709 depends on NUMA
1710
da85f865 1711menu "Power management and ACPI options"
e279b6c1
SR
1712
1713config ARCH_HIBERNATION_HEADER
3c2362e6 1714 def_bool y
e279b6c1 1715 depends on X86_64 && HIBERNATION
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SR
1716
1717source "kernel/power/Kconfig"
1718
1719source "drivers/acpi/Kconfig"
1720
efafc8b2
FT
1721source "drivers/sfi/Kconfig"
1722
a6b68076 1723config X86_APM_BOOT
6fc108a0 1724 def_bool y
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AK
1725 depends on APM || APM_MODULE
1726
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SR
1727menuconfig APM
1728 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 1729 depends on X86_32 && PM_SLEEP
e279b6c1
SR
1730 ---help---
1731 APM is a BIOS specification for saving power using several different
1732 techniques. This is mostly useful for battery powered laptops with
1733 APM compliant BIOSes. If you say Y here, the system time will be
1734 reset after a RESUME operation, the /proc/apm device will provide
1735 battery status information, and user-space programs will receive
1736 notification of APM "events" (e.g. battery status change).
1737
1738 If you select "Y" here, you can disable actual use of the APM
1739 BIOS by passing the "apm=off" option to the kernel at boot time.
1740
1741 Note that the APM support is almost completely disabled for
1742 machines with more than one CPU.
1743
1744 In order to use APM, you will need supporting software. For location
53471121 1745 and more information, read <file:Documentation/power/pm.txt> and the
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SR
1746 Battery Powered Linux mini-HOWTO, available from
1747 <http://www.tldp.org/docs.html#howto>.
1748
1749 This driver does not spin down disk drives (see the hdparm(8)
1750 manpage ("man 8 hdparm") for that), and it doesn't turn off
1751 VESA-compliant "green" monitors.
1752
1753 This driver does not support the TI 4000M TravelMate and the ACER
1754 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1755 desktop machines also don't have compliant BIOSes, and this driver
1756 may cause those machines to panic during the boot phase.
1757
1758 Generally, if you don't have a battery in your machine, there isn't
1759 much point in using this driver and you should say N. If you get
1760 random kernel OOPSes or reboots that don't seem to be related to
1761 anything, try disabling/enabling this option (or disabling/enabling
1762 APM in your BIOS).
1763
1764 Some other things you should try when experiencing seemingly random,
1765 "weird" problems:
1766
1767 1) make sure that you have enough swap space and that it is
1768 enabled.
1769 2) pass the "no-hlt" option to the kernel
1770 3) switch on floating point emulation in the kernel and pass
1771 the "no387" option to the kernel
1772 4) pass the "floppy=nodma" option to the kernel
1773 5) pass the "mem=4M" option to the kernel (thereby disabling
1774 all but the first 4 MB of RAM)
1775 6) make sure that the CPU is not over clocked.
1776 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1777 8) disable the cache from your BIOS settings
1778 9) install a fan for the video card or exchange video RAM
1779 10) install a better fan for the CPU
1780 11) exchange RAM chips
1781 12) exchange the motherboard.
1782
1783 To compile this driver as a module, choose M here: the
1784 module will be called apm.
1785
1786if APM
1787
1788config APM_IGNORE_USER_SUSPEND
1789 bool "Ignore USER SUSPEND"
8f9ca475 1790 ---help---
e279b6c1
SR
1791 This option will ignore USER SUSPEND requests. On machines with a
1792 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1793 series notebooks, it is necessary to say Y because of a BIOS bug.
1794
1795config APM_DO_ENABLE
1796 bool "Enable PM at boot time"
1797 ---help---
1798 Enable APM features at boot time. From page 36 of the APM BIOS
1799 specification: "When disabled, the APM BIOS does not automatically
1800 power manage devices, enter the Standby State, enter the Suspend
1801 State, or take power saving steps in response to CPU Idle calls."
1802 This driver will make CPU Idle calls when Linux is idle (unless this
1803 feature is turned off -- see "Do CPU IDLE calls", below). This
1804 should always save battery power, but more complicated APM features
1805 will be dependent on your BIOS implementation. You may need to turn
1806 this option off if your computer hangs at boot time when using APM
1807 support, or if it beeps continuously instead of suspending. Turn
1808 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1809 T400CDT. This is off by default since most machines do fine without
1810 this feature.
1811
1812config APM_CPU_IDLE
1813 bool "Make CPU Idle calls when idle"
8f9ca475 1814 ---help---
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SR
1815 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1816 On some machines, this can activate improved power savings, such as
1817 a slowed CPU clock rate, when the machine is idle. These idle calls
1818 are made after the idle loop has run for some length of time (e.g.,
1819 333 mS). On some machines, this will cause a hang at boot time or
1820 whenever the CPU becomes idle. (On machines with more than one CPU,
1821 this option does nothing.)
1822
1823config APM_DISPLAY_BLANK
1824 bool "Enable console blanking using APM"
8f9ca475 1825 ---help---
e279b6c1
SR
1826 Enable console blanking using the APM. Some laptops can use this to
1827 turn off the LCD backlight when the screen blanker of the Linux
1828 virtual console blanks the screen. Note that this is only used by
1829 the virtual console screen blanker, and won't turn off the backlight
1830 when using the X Window system. This also doesn't have anything to
1831 do with your VESA-compliant power-saving monitor. Further, this
1832 option doesn't work for all laptops -- it might not turn off your
1833 backlight at all, or it might print a lot of errors to the console,
1834 especially if you are using gpm.
1835
1836config APM_ALLOW_INTS
1837 bool "Allow interrupts during APM BIOS calls"
8f9ca475 1838 ---help---
e279b6c1
SR
1839 Normally we disable external interrupts while we are making calls to
1840 the APM BIOS as a measure to lessen the effects of a badly behaving
1841 BIOS implementation. The BIOS should reenable interrupts if it
1842 needs to. Unfortunately, some BIOSes do not -- especially those in
1843 many of the newer IBM Thinkpads. If you experience hangs when you
1844 suspend, try setting this to Y. Otherwise, say N.
1845
e279b6c1
SR
1846endif # APM
1847
1848source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1849
1850source "drivers/cpuidle/Kconfig"
1851
27471fdb
AH
1852source "drivers/idle/Kconfig"
1853
e279b6c1
SR
1854endmenu
1855
1856
1857menu "Bus options (PCI etc.)"
1858
1859config PCI
1ac97018 1860 bool "PCI support"
1c858087 1861 default y
e279b6c1 1862 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
8f9ca475 1863 ---help---
e279b6c1
SR
1864 Find out whether you have a PCI motherboard. PCI is the name of a
1865 bus system, i.e. the way the CPU talks to the other stuff inside
1866 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1867 VESA. If you have PCI, say Y, otherwise N.
1868
e279b6c1
SR
1869choice
1870 prompt "PCI access mode"
efefa6f6 1871 depends on X86_32 && PCI
e279b6c1
SR
1872 default PCI_GOANY
1873 ---help---
1874 On PCI systems, the BIOS can be used to detect the PCI devices and
1875 determine their configuration. However, some old PCI motherboards
1876 have BIOS bugs and may crash if this is done. Also, some embedded
1877 PCI-based systems don't have any BIOS at all. Linux can also try to
1878 detect the PCI hardware directly without using the BIOS.
1879
1880 With this option, you can specify how Linux should detect the
1881 PCI devices. If you choose "BIOS", the BIOS will be used,
1882 if you choose "Direct", the BIOS won't be used, and if you
1883 choose "MMConfig", then PCI Express MMCONFIG will be used.
1884 If you choose "Any", the kernel will try MMCONFIG, then the
1885 direct access method and falls back to the BIOS if that doesn't
1886 work. If unsure, go with the default, which is "Any".
1887
1888config PCI_GOBIOS
1889 bool "BIOS"
1890
1891config PCI_GOMMCONFIG
1892 bool "MMConfig"
1893
1894config PCI_GODIRECT
1895 bool "Direct"
1896
3ef0e1f8
AS
1897config PCI_GOOLPC
1898 bool "OLPC"
1899 depends on OLPC
1900
2bdd1b03
AS
1901config PCI_GOANY
1902 bool "Any"
1903
e279b6c1
SR
1904endchoice
1905
1906config PCI_BIOS
3c2362e6 1907 def_bool y
efefa6f6 1908 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
e279b6c1
SR
1909
1910# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1911config PCI_DIRECT
3c2362e6 1912 def_bool y
efefa6f6 1913 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
e279b6c1
SR
1914
1915config PCI_MMCONFIG
3c2362e6 1916 def_bool y
5f0db7a2 1917 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 1918
3ef0e1f8 1919config PCI_OLPC
2bdd1b03
AS
1920 def_bool y
1921 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 1922
e279b6c1 1923config PCI_DOMAINS
3c2362e6 1924 def_bool y
e279b6c1 1925 depends on PCI
e279b6c1
SR
1926
1927config PCI_MMCONFIG
1928 bool "Support mmconfig PCI config space access"
1929 depends on X86_64 && PCI && ACPI
1930
3f6ea84a
IS
1931config PCI_CNB20LE_QUIRK
1932 bool "Read CNB20LE Host Bridge Windows"
1933 depends on PCI
1934 help
1935 Read the PCI windows out of the CNB20LE host bridge. This allows
1936 PCI hotplug to work on systems with the CNB20LE chipset which do
1937 not have ACPI.
1938
e279b6c1
SR
1939config DMAR
1940 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
4cf2e75d 1941 depends on PCI_MSI && ACPI && EXPERIMENTAL
e279b6c1
SR
1942 help
1943 DMA remapping (DMAR) devices support enables independent address
1944 translations for Direct Memory Access (DMA) from devices.
1945 These DMA remapping devices are reported via ACPI tables
1946 and include PCI device scope covered by these DMA
1947 remapping devices.
1948
0cd5c3c8 1949config DMAR_DEFAULT_ON
f6be37fd 1950 def_bool y
0cd5c3c8
KM
1951 prompt "Enable DMA Remapping Devices by default"
1952 depends on DMAR
1953 help
1954 Selecting this option will enable a DMAR device at boot time if
1955 one is found. If this option is not selected, DMAR support can
1956 be enabled by passing intel_iommu=on to the kernel. It is
1957 recommended you say N here while the DMAR code remains
1958 experimental.
1959
62edf5dc 1960config DMAR_BROKEN_GFX_WA
6fc108a0 1961 bool "Workaround broken graphics drivers (going away soon)"
0c02a20f 1962 depends on DMAR && BROKEN
62edf5dc
DW
1963 ---help---
1964 Current Graphics drivers tend to use physical address
1965 for DMA and avoid using DMA APIs. Setting this config
1966 option permits the IOMMU driver to set a unity map for
1967 all the OS-visible memory. Hence the driver can continue
1968 to use physical addresses for DMA, at least until this
1969 option is removed in the 2.6.32 kernel.
1970
e279b6c1 1971config DMAR_FLOPPY_WA
3c2362e6 1972 def_bool y
e279b6c1 1973 depends on DMAR
8f9ca475 1974 ---help---
c7ab48d2 1975 Floppy disk drivers are known to bypass DMA API calls
8f9ca475
IM
1976 thereby failing to work when IOMMU is enabled. This
1977 workaround will setup a 1:1 mapping for the first
c7ab48d2 1978 16MiB to make floppy (an ISA device) work.
e279b6c1 1979
9fa8c481
SS
1980config INTR_REMAP
1981 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1982 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
8f9ca475
IM
1983 ---help---
1984 Supports Interrupt remapping for IO-APIC and MSI devices.
1985 To use x2apic mode in the CPU's which support x2APIC enhancements or
1986 to support platforms with CPU's having > 8 bit APIC ID, say Y.
9fa8c481 1987
e279b6c1
SR
1988source "drivers/pci/pcie/Kconfig"
1989
1990source "drivers/pci/Kconfig"
1991
1992# x86_64 have no ISA slots, but do have ISA-style DMA.
1993config ISA_DMA_API
3c2362e6 1994 def_bool y
e279b6c1
SR
1995
1996if X86_32
1997
1998config ISA
1999 bool "ISA support"
8f9ca475 2000 ---help---
e279b6c1
SR
2001 Find out whether you have ISA slots on your motherboard. ISA is the
2002 name of a bus system, i.e. the way the CPU talks to the other stuff
2003 inside your box. Other bus systems are PCI, EISA, MicroChannel
2004 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2005 newer boards don't support it. If you have ISA, say Y, otherwise N.
2006
2007config EISA
2008 bool "EISA support"
2009 depends on ISA
2010 ---help---
2011 The Extended Industry Standard Architecture (EISA) bus was
2012 developed as an open alternative to the IBM MicroChannel bus.
2013
2014 The EISA bus provided some of the features of the IBM MicroChannel
2015 bus while maintaining backward compatibility with cards made for
2016 the older ISA bus. The EISA bus saw limited use between 1988 and
2017 1995 when it was made obsolete by the PCI bus.
2018
2019 Say Y here if you are building a kernel for an EISA-based machine.
2020
2021 Otherwise, say N.
2022
2023source "drivers/eisa/Kconfig"
2024
2025config MCA
72ee6ebb 2026 bool "MCA support"
8f9ca475 2027 ---help---
e279b6c1
SR
2028 MicroChannel Architecture is found in some IBM PS/2 machines and
2029 laptops. It is a bus system similar to PCI or ISA. See
2030 <file:Documentation/mca.txt> (and especially the web page given
2031 there) before attempting to build an MCA bus kernel.
2032
2033source "drivers/mca/Kconfig"
2034
2035config SCx200
2036 tristate "NatSemi SCx200 support"
8f9ca475 2037 ---help---
e279b6c1
SR
2038 This provides basic support for National Semiconductor's
2039 (now AMD's) Geode processors. The driver probes for the
2040 PCI-IDs of several on-chip devices, so its a good dependency
2041 for other scx200_* drivers.
2042
2043 If compiled as a module, the driver is named scx200.
2044
2045config SCx200HR_TIMER
2046 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
592913ec 2047 depends on SCx200
e279b6c1 2048 default y
8f9ca475 2049 ---help---
e279b6c1
SR
2050 This driver provides a clocksource built upon the on-chip
2051 27MHz high-resolution timer. Its also a workaround for
2052 NSC Geode SC-1100's buggy TSC, which loses time when the
2053 processor goes idle (as is done by the scheduler). The
2054 other workaround is idle=poll boot option.
2055
3ef0e1f8
AS
2056config OLPC
2057 bool "One Laptop Per Child support"
3c554946 2058 select GPIOLIB
8f9ca475 2059 ---help---
3ef0e1f8
AS
2060 Add support for detecting the unique features of the OLPC
2061 XO hardware.
2062
fd699c76
AS
2063config OLPC_OPENFIRMWARE
2064 bool "Support for OLPC's Open Firmware"
2065 depends on !X86_64 && !X86_PAE
2066 default y if OLPC
2067 help
2068 This option adds support for the implementation of Open Firmware
2069 that is used on the OLPC XO-1 Children's Machine.
2070 If unsure, say N here.
2071
bc0120fd
SR
2072endif # X86_32
2073
e279b6c1
SR
2074config K8_NB
2075 def_bool y
0e152cd7 2076 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2077
2078source "drivers/pcmcia/Kconfig"
2079
2080source "drivers/pci/hotplug/Kconfig"
2081
2082endmenu
2083
2084
2085menu "Executable file formats / Emulations"
2086
2087source "fs/Kconfig.binfmt"
2088
2089config IA32_EMULATION
2090 bool "IA32 Emulation"
2091 depends on X86_64
a97f52e6 2092 select COMPAT_BINFMT_ELF
8f9ca475 2093 ---help---
e279b6c1
SR
2094 Include code to run 32-bit programs under a 64-bit kernel. You should
2095 likely turn this on, unless you're 100% sure that you don't have any
2096 32-bit programs left.
2097
2098config IA32_AOUT
8f9ca475
IM
2099 tristate "IA32 a.out support"
2100 depends on IA32_EMULATION
2101 ---help---
2102 Support old a.out binaries in the 32bit emulation.
e279b6c1
SR
2103
2104config COMPAT
3c2362e6 2105 def_bool y
e279b6c1 2106 depends on IA32_EMULATION
e279b6c1
SR
2107
2108config COMPAT_FOR_U64_ALIGNMENT
2109 def_bool COMPAT
2110 depends on X86_64
2111
2112config SYSVIPC_COMPAT
3c2362e6 2113 def_bool y
b8992195 2114 depends on COMPAT && SYSVIPC
e279b6c1
SR
2115
2116endmenu
2117
2118
e5beae16
KP
2119config HAVE_ATOMIC_IOMAP
2120 def_bool y
2121 depends on X86_32
2122
e279b6c1
SR
2123source "net/Kconfig"
2124
2125source "drivers/Kconfig"
2126
2127source "drivers/firmware/Kconfig"
2128
2129source "fs/Kconfig"
2130
e279b6c1
SR
2131source "arch/x86/Kconfig.debug"
2132
2133source "security/Kconfig"
2134
2135source "crypto/Kconfig"
2136
edf88417
AK
2137source "arch/x86/kvm/Kconfig"
2138
e279b6c1 2139source "lib/Kconfig"