Merge branch 'x86-irq-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6-block.git] / arch / x86 / Kconfig
CommitLineData
1032c0ba 1# x86 configuration
daa93fab
SR
2mainmenu "Linux Kernel Configuration for x86"
3
4# Select 32 or 64 bit
5config 64BIT
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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
FW
57 select PERF_EVENTS
58 select ANON_INODES
0a4af3b0 59 select HAVE_ARCH_KMEMCHECK
7c68af6e 60 select HAVE_USER_RETURN_NOTIFIER
7d8330a5 61
ba7e4d13
IM
62config INSTRUCTION_DECODER
63 def_bool (KPROBES || PERF_EVENTS)
64
51b26ada
LT
65config OUTPUT_FORMAT
66 string
67 default "elf32-i386" if X86_32
68 default "elf64-x86-64" if X86_64
69
73531905 70config ARCH_DEFCONFIG
b9b39bfb 71 string
73531905
SR
72 default "arch/x86/configs/i386_defconfig" if X86_32
73 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 74
8d5fffb9 75config GENERIC_TIME
3c2362e6 76 def_bool y
8d5fffb9
SR
77
78config GENERIC_CMOS_UPDATE
3c2362e6 79 def_bool y
8d5fffb9
SR
80
81config CLOCKSOURCE_WATCHDOG
3c2362e6 82 def_bool y
8d5fffb9
SR
83
84config GENERIC_CLOCKEVENTS
3c2362e6 85 def_bool y
8d5fffb9
SR
86
87config GENERIC_CLOCKEVENTS_BROADCAST
3c2362e6 88 def_bool y
8d5fffb9
SR
89 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
90
91config LOCKDEP_SUPPORT
3c2362e6 92 def_bool y
8d5fffb9
SR
93
94config STACKTRACE_SUPPORT
3c2362e6 95 def_bool y
8d5fffb9 96
aa7d9350
HC
97config HAVE_LATENCYTOP_SUPPORT
98 def_bool y
99
8d5fffb9 100config MMU
3c2362e6 101 def_bool y
8d5fffb9
SR
102
103config ZONE_DMA
3c2362e6 104 def_bool y
8d5fffb9 105
8d5fffb9
SR
106config SBUS
107 bool
108
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FT
109config NEED_DMA_MAP_STATE
110 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
111
8d5fffb9 112config GENERIC_ISA_DMA
3c2362e6 113 def_bool y
8d5fffb9
SR
114
115config GENERIC_IOMAP
3c2362e6 116 def_bool y
8d5fffb9
SR
117
118config GENERIC_BUG
3c2362e6 119 def_bool y
8d5fffb9 120 depends on BUG
b93a531e
JB
121 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
122
123config GENERIC_BUG_RELATIVE_POINTERS
124 bool
8d5fffb9
SR
125
126config GENERIC_HWEIGHT
3c2362e6 127 def_bool y
8d5fffb9 128
a6082959 129config GENERIC_GPIO
9ba16087 130 bool
a6082959 131
8d5fffb9 132config ARCH_MAY_HAVE_PC_FDC
3c2362e6 133 def_bool y
8d5fffb9 134
1032c0ba
SR
135config RWSEM_GENERIC_SPINLOCK
136 def_bool !X86_XADD
137
138config RWSEM_XCHGADD_ALGORITHM
139 def_bool X86_XADD
140
a6869cc4
VP
141config ARCH_HAS_CPU_IDLE_WAIT
142 def_bool y
143
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SR
144config GENERIC_CALIBRATE_DELAY
145 def_bool y
146
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SR
147config GENERIC_TIME_VSYSCALL
148 bool
149 default X86_64
150
9a0b8415 151config ARCH_HAS_CPU_RELAX
152 def_bool y
153
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VP
154config ARCH_HAS_DEFAULT_IDLE
155 def_bool y
156
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PE
157config ARCH_HAS_CACHE_LINE_SIZE
158 def_bool y
159
dd5af90a 160config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 161 def_bool y
b32ef636 162
08fc4580
TH
163config NEED_PER_CPU_EMBED_FIRST_CHUNK
164 def_bool y
165
166config NEED_PER_CPU_PAGE_FIRST_CHUNK
11124411
TH
167 def_bool y
168
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MT
169config HAVE_CPUMASK_OF_CPU_MAP
170 def_bool X86_64_SMP
171
801e4062
JB
172config ARCH_HIBERNATION_POSSIBLE
173 def_bool y
801e4062 174
f4cb5700
JB
175config ARCH_SUSPEND_POSSIBLE
176 def_bool y
f4cb5700 177
8d5fffb9
SR
178config ZONE_DMA32
179 bool
180 default X86_64
181
182config ARCH_POPULATES_NODE_MAP
183 def_bool y
184
185config AUDIT_ARCH
186 bool
187 default X86_64
188
765c68bd
IM
189config ARCH_SUPPORTS_OPTIMIZED_INLINING
190 def_bool y
191
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AM
192config ARCH_SUPPORTS_DEBUG_PAGEALLOC
193 def_bool y
194
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YL
195config HAVE_EARLY_RES
196 def_bool y
197
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198config HAVE_INTEL_TXT
199 def_bool y
200 depends on EXPERIMENTAL && DMAR && ACPI
201
8d5fffb9
SR
202# Use the generic interrupt handling code in kernel/irq/:
203config GENERIC_HARDIRQS
6fc108a0 204 def_bool y
8d5fffb9 205
f9a36fa5
TG
206config GENERIC_HARDIRQS_NO__DO_IRQ
207 def_bool y
208
8d5fffb9 209config GENERIC_IRQ_PROBE
6fc108a0 210 def_bool y
8d5fffb9
SR
211
212config GENERIC_PENDING_IRQ
6fc108a0 213 def_bool y
8d5fffb9 214 depends on GENERIC_HARDIRQS && SMP
8d5fffb9 215
6cd10f8d
JB
216config USE_GENERIC_SMP_HELPERS
217 def_bool y
218 depends on SMP
219
6b0c3d44
SR
220config X86_32_SMP
221 def_bool y
222 depends on X86_32 && SMP
223
224config X86_64_SMP
225 def_bool y
226 depends on X86_64 && SMP
227
8d5fffb9 228config X86_HT
6fc108a0 229 def_bool y
ee0011a7 230 depends on SMP
8d5fffb9
SR
231
232config X86_TRAMPOLINE
6fc108a0 233 def_bool y
3e5095d1 234 depends on SMP || (64BIT && ACPI_SLEEP)
8d5fffb9 235
ccbeed3a
TH
236config X86_32_LAZY_GS
237 def_bool y
60a5317f 238 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 239
8d5fffb9
SR
240config KTIME_SCALAR
241 def_bool X86_32
506f1d07 242source "init/Kconfig"
dc52ddc0 243source "kernel/Kconfig.freezer"
8d5fffb9 244
506f1d07
SR
245menu "Processor type and features"
246
247source "kernel/time/Kconfig"
248
249config SMP
250 bool "Symmetric multi-processing support"
251 ---help---
252 This enables support for systems with more than one CPU. If you have
253 a system with only one CPU, like most personal computers, say N. If
254 you have a system with more than one CPU, say Y.
255
256 If you say N here, the kernel will run on single and multiprocessor
257 machines, but will use only one CPU of a multiprocessor machine. If
258 you say Y here, the kernel will run on many, but not all,
259 singleprocessor machines. On a singleprocessor machine, the kernel
260 will run faster if you say N here.
261
262 Note that if you say Y here and choose architecture "586" or
263 "Pentium" under "Processor family", the kernel will not work on 486
264 architectures. Similarly, multiprocessor kernels for the "PPro"
265 architecture may not work on all Pentium based boards.
266
267 People using multiprocessor machines who say Y here should also say
268 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
269 Management" code will be disabled if you say Y here.
270
03502faa 271 See also <file:Documentation/i386/IO-APIC.txt>,
506f1d07
SR
272 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
273 <http://www.tldp.org/docs.html#howto>.
274
275 If you don't know what to do here, say N.
276
06cd9a7d
YL
277config X86_X2APIC
278 bool "Support x2apic"
f7d7f866 279 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
06cd9a7d
YL
280 ---help---
281 This enables x2apic support on CPUs that have this feature.
282
283 This allows 32-bit apic IDs (so it can support very large systems),
284 and accesses the local apic via MSRs not via mmio.
285
06cd9a7d
YL
286 If you don't know what to do here, say N.
287
0b8f1efa
YL
288config SPARSE_IRQ
289 bool "Support sparse irq numbering"
17483a1f 290 depends on PCI_MSI || HT_IRQ
8f9ca475 291 ---help---
973656fe
IM
292 This enables support for sparse irqs. This is useful for distro
293 kernels that want to define a high CONFIG_NR_CPUS value but still
294 want to have low kernel memory footprint on smaller machines.
0b8f1efa 295
973656fe
IM
296 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
297 out the irq_desc[] array in a more NUMA-friendly way. )
298
299 If you don't know what to do here, say N.
0b8f1efa 300
15e957d0
YL
301config NUMA_IRQ_DESC
302 def_bool y
b9098957 303 depends on SPARSE_IRQ && NUMA
48a1b10a 304
6695c85b 305config X86_MPPARSE
7a527688
JB
306 bool "Enable MPS table" if ACPI
307 default y
5ab74722 308 depends on X86_LOCAL_APIC
8f9ca475 309 ---help---
6695c85b
YL
310 For old smp systems that do not have proper acpi support. Newer systems
311 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 312
26f7ef14
YL
313config X86_BIGSMP
314 bool "Support for big SMP systems with more than 8 CPUs"
315 depends on X86_32 && SMP
8f9ca475 316 ---help---
26f7ef14 317 This option is needed for the systems that have more than 8 CPUs
506f1d07 318
8425091f 319if X86_32
c5c606d9
RT
320config X86_EXTENDED_PLATFORM
321 bool "Support for extended (non-PC) x86 platforms"
322 default y
8f9ca475 323 ---help---
06ac8346
IM
324 If you disable this option then the kernel will only support
325 standard PC platforms. (which covers the vast majority of
326 systems out there.)
327
8425091f
RT
328 If you enable this option then you'll be able to select support
329 for the following (non-PC) 32 bit x86 platforms:
330 AMD Elan
331 NUMAQ (IBM/Sequent)
332 RDC R-321x SoC
333 SGI 320/540 (Visual Workstation)
334 Summit/EXA (IBM x440)
335 Unisys ES7000 IA32 series
3f4110a4 336 Moorestown MID devices
06ac8346
IM
337
338 If you have one of these systems, or if you want to build a
339 generic distribution kernel, say Y here - otherwise say N.
8425091f 340endif
06ac8346 341
8425091f
RT
342if X86_64
343config X86_EXTENDED_PLATFORM
344 bool "Support for extended (non-PC) x86 platforms"
345 default y
346 ---help---
347 If you disable this option then the kernel will only support
348 standard PC platforms. (which covers the vast majority of
349 systems out there.)
350
351 If you enable this option then you'll be able to select support
352 for the following (non-PC) 64 bit x86 platforms:
353 ScaleMP vSMP
354 SGI Ultraviolet
355
356 If you have one of these systems, or if you want to build a
357 generic distribution kernel, say Y here - otherwise say N.
358endif
c5c606d9
RT
359# This is an alphabetically sorted list of 64 bit extended platforms
360# Please maintain the alphabetic order if and when there are additions
506f1d07 361
c5c606d9
RT
362config X86_VSMP
363 bool "ScaleMP vSMP"
364 select PARAVIRT
365 depends on X86_64 && PCI
366 depends on X86_EXTENDED_PLATFORM
8f9ca475 367 ---help---
c5c606d9
RT
368 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
369 supposed to run on these EM64T-based machines. Only choose this option
370 if you have one of these machines.
5e3a77e9 371
03b48632
NP
372config X86_UV
373 bool "SGI Ultraviolet"
374 depends on X86_64
c5c606d9 375 depends on X86_EXTENDED_PLATFORM
54c28d29 376 depends on NUMA
9d6c26e7 377 depends on X86_X2APIC
8f9ca475 378 ---help---
03b48632
NP
379 This option is needed in order to support SGI Ultraviolet systems.
380 If you don't have one of these, you should say N here.
381
c5c606d9
RT
382# Following is an alphabetically sorted list of 32 bit extended platforms
383# Please maintain the alphabetic order if and when there are additions
506f1d07
SR
384
385config X86_ELAN
386 bool "AMD Elan"
387 depends on X86_32
c5c606d9 388 depends on X86_EXTENDED_PLATFORM
8f9ca475 389 ---help---
506f1d07
SR
390 Select this for an AMD Elan processor.
391
392 Do not use this option for K6/Athlon/Opteron processors!
393
394 If unsure, choose "PC-compatible" instead.
395
3f4110a4
TG
396config X86_MRST
397 bool "Moorestown MID platform"
4b2f3f7d
JP
398 depends on PCI
399 depends on PCI_GOANY
3f4110a4
TG
400 depends on X86_32
401 depends on X86_EXTENDED_PLATFORM
4b2f3f7d 402 depends on X86_IO_APIC
bb24c471 403 select APB_TIMER
3f4110a4
TG
404 ---help---
405 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
406 Internet Device(MID) platform. Moorestown consists of two chips:
407 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
408 Unlike standard x86 PCs, Moorestown does not have many legacy devices
409 nor standard legacy replacement devices/features. e.g. Moorestown does
410 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
411
c5c606d9
RT
412config X86_RDC321X
413 bool "RDC R-321x SoC"
506f1d07 414 depends on X86_32
c5c606d9
RT
415 depends on X86_EXTENDED_PLATFORM
416 select M486
417 select X86_REBOOTFIXUPS
418 ---help---
419 This option is needed for RDC R-321x system-on-chip, also known
420 as R-8610-(G).
421 If you don't have one of these chips, you should say N here.
422
e0c7ae37 423config X86_32_NON_STANDARD
9c398017
IM
424 bool "Support non-standard 32-bit SMP architectures"
425 depends on X86_32 && SMP
c5c606d9 426 depends on X86_EXTENDED_PLATFORM
8f9ca475
IM
427 ---help---
428 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
d49c4288
YL
429 subarchitectures. It is intended for a generic binary kernel.
430 if you select them all, kernel will probe it one by one. and will
431 fallback to default.
432
c5c606d9 433# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 434
506f1d07
SR
435config X86_NUMAQ
436 bool "NUMAQ (IBM/Sequent)"
e0c7ae37 437 depends on X86_32_NON_STANDARD
a92d152e 438 depends on PCI
506f1d07 439 select NUMA
9c398017 440 select X86_MPPARSE
8f9ca475 441 ---help---
d49c4288
YL
442 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
443 NUMA multiquad box. This changes the way that processors are
444 bootstrapped, and uses Clustered Logical APIC addressing mode instead
445 of Flat Logical. You will need a new lynxer.elf file to flash your
446 firmware with - send email to <Martin.Bligh@us.ibm.com>.
506f1d07 447
d949f36f 448config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 449 def_bool y
d949f36f
LT
450 # MCE code calls memory_failure():
451 depends on X86_MCE
452 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
453 depends on !X86_NUMAQ
454 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
455 depends on X86_64 || !SPARSEMEM
456 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 457
1b84e1c8
IM
458config X86_VISWS
459 bool "SGI 320/540 (Visual Workstation)"
c5c606d9
RT
460 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
461 depends on X86_32_NON_STANDARD
462 ---help---
1b84e1c8
IM
463 The SGI Visual Workstation series is an IA32-based workstation
464 based on SGI systems chips with some legacy PC hardware attached.
465
466 Say Y here to create a kernel to run on the SGI 320 or 540.
467
468 A kernel compiled for the Visual Workstation will run on general
469 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
470
9c398017
IM
471config X86_SUMMIT
472 bool "Summit/EXA (IBM x440)"
e0c7ae37 473 depends on X86_32_NON_STANDARD
8f9ca475 474 ---help---
9c398017
IM
475 This option is needed for IBM systems that use the Summit/EXA chipset.
476 In particular, it is needed for the x440.
1f972768 477
9c398017 478config X86_ES7000
c5c606d9 479 bool "Unisys ES7000 IA32 series"
26f7ef14 480 depends on X86_32_NON_STANDARD && X86_BIGSMP
8f9ca475 481 ---help---
9c398017
IM
482 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
483 supposed to run on an IA32-based Unisys ES7000 system.
484
ae1e9130 485config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
486 def_bool y
487 prompt "Single-depth WCHAN output"
a87d0914 488 depends on X86
8f9ca475 489 ---help---
506f1d07
SR
490 Calculate simpler /proc/<PID>/wchan values. If this option
491 is disabled then wchan values will recurse back to the
492 caller function. This provides more accurate wchan values,
493 at the expense of slightly more scheduling overhead.
494
495 If in doubt, say "Y".
496
506f1d07
SR
497menuconfig PARAVIRT_GUEST
498 bool "Paravirtualized guest support"
8f9ca475 499 ---help---
506f1d07
SR
500 Say Y here to get to see options related to running Linux under
501 various hypervisors. This option alone does not add any kernel code.
502
503 If you say N, all options in this submenu will be skipped and disabled.
504
505if PARAVIRT_GUEST
506
507source "arch/x86/xen/Kconfig"
508
509config VMI
d0153ca3 510 bool "VMI Guest support (DEPRECATED)"
506f1d07 511 select PARAVIRT
42d545c9 512 depends on X86_32
8f9ca475 513 ---help---
506f1d07
SR
514 VMI provides a paravirtualized interface to the VMware ESX server
515 (it could be used by other hypervisors in theory too, but is not
516 at the moment), by linking the kernel to a GPL-ed ROM module
517 provided by the hypervisor.
518
d0153ca3
AK
519 As of September 2009, VMware has started a phased retirement
520 of this feature from VMware's products. Please see
521 feature-removal-schedule.txt for details. If you are
522 planning to enable this option, please note that you cannot
523 live migrate a VMI enabled VM to a future VMware product,
524 which doesn't support VMI. So if you expect your kernel to
525 seamlessly migrate to newer VMware products, keep this
526 disabled.
527
790c73f6
GOC
528config KVM_CLOCK
529 bool "KVM paravirtualized clock"
530 select PARAVIRT
f6e16d5a 531 select PARAVIRT_CLOCK
8f9ca475 532 ---help---
790c73f6
GOC
533 Turning on this option will allow you to run a paravirtualized clock
534 when running over the KVM hypervisor. Instead of relying on a PIT
535 (or probably other) emulation by the underlying device model, the host
536 provides the guest with timing infrastructure such as time of day, and
537 system time
538
0cf1bfd2
MT
539config KVM_GUEST
540 bool "KVM Guest support"
541 select PARAVIRT
8f9ca475
IM
542 ---help---
543 This option enables various optimizations for running under the KVM
544 hypervisor.
0cf1bfd2 545
506f1d07
SR
546source "arch/x86/lguest/Kconfig"
547
e61bd94a
EPH
548config PARAVIRT
549 bool "Enable paravirtualization code"
8f9ca475 550 ---help---
e61bd94a
EPH
551 This changes the kernel so it can modify itself when it is run
552 under a hypervisor, potentially improving performance significantly
553 over full virtualization. However, when run without a hypervisor
554 the kernel is theoretically slower and slightly larger.
555
b4ecc126
JF
556config PARAVIRT_SPINLOCKS
557 bool "Paravirtualization layer for spinlocks"
558 depends on PARAVIRT && SMP && EXPERIMENTAL
559 ---help---
560 Paravirtualized spinlocks allow a pvops backend to replace the
561 spinlock implementation with something virtualization-friendly
562 (for example, block the virtual CPU rather than spinning).
563
564 Unfortunately the downside is an up to 5% performance hit on
565 native kernels, with various workloads.
566
567 If you are unsure how to answer this question, answer N.
568
7af192c9
GH
569config PARAVIRT_CLOCK
570 bool
7af192c9 571
506f1d07
SR
572endif
573
97349135 574config PARAVIRT_DEBUG
8f9ca475
IM
575 bool "paravirt-ops debugging"
576 depends on PARAVIRT && DEBUG_KERNEL
577 ---help---
578 Enable to debug paravirt_ops internals. Specifically, BUG if
579 a paravirt_op is missing when it is called.
97349135 580
08677214
YL
581config NO_BOOTMEM
582 default y
583 bool "Disable Bootmem code"
08677214
YL
584 ---help---
585 Use early_res directly instead of bootmem before slab is ready.
586 - allocator (buddy) [generic]
587 - early allocator (bootmem) [generic]
588 - very early allocator (reserve_early*()) [x86]
589 - very very early allocator (early brk model) [x86]
590 So reduce one layer between early allocator to final allocator
591
592
03273184
YL
593config MEMTEST
594 bool "Memtest"
8f9ca475 595 ---help---
c64df707 596 This option adds a kernel parameter 'memtest', which allows memtest
03273184 597 to be set.
8f9ca475
IM
598 memtest=0, mean disabled; -- default
599 memtest=1, mean do 1 test pattern;
600 ...
601 memtest=4, mean do 4 test patterns.
aba3728c 602 If you are unsure how to answer this question, answer N.
506f1d07
SR
603
604config X86_SUMMIT_NUMA
3c2362e6 605 def_bool y
e0c7ae37 606 depends on X86_32 && NUMA && X86_32_NON_STANDARD
506f1d07
SR
607
608config X86_CYCLONE_TIMER
3c2362e6 609 def_bool y
e0c7ae37 610 depends on X86_32_NON_STANDARD
506f1d07 611
506f1d07
SR
612source "arch/x86/Kconfig.cpu"
613
614config HPET_TIMER
3c2362e6 615 def_bool X86_64
506f1d07 616 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
617 ---help---
618 Use the IA-PC HPET (High Precision Event Timer) to manage
619 time in preference to the PIT and RTC, if a HPET is
620 present.
621 HPET is the next generation timer replacing legacy 8254s.
622 The HPET provides a stable time base on SMP
623 systems, unlike the TSC, but it is more expensive to access,
624 as it is off-chip. You can find the HPET spec at
625 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
506f1d07 626
8f9ca475
IM
627 You can safely choose Y here. However, HPET will only be
628 activated if the platform and the BIOS support this feature.
629 Otherwise the 8254 will be used for timing services.
506f1d07 630
8f9ca475 631 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
632
633config HPET_EMULATE_RTC
3c2362e6 634 def_bool y
9d8af78b 635 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 636
bb24c471
JP
637config APB_TIMER
638 def_bool y if MRST
639 prompt "Langwell APB Timer Support" if X86_MRST
640 help
641 APB timer is the replacement for 8254, HPET on X86 MID platforms.
642 The APBT provides a stable time base on SMP
643 systems, unlike the TSC, but it is more expensive to access,
644 as it is off-chip. APB timers are always running regardless of CPU
645 C states, they are used as per CPU clockevent device when possible.
646
506f1d07
SR
647# Mark as embedded because too many people got it wrong.
648# The code disables itself when not needed.
7ae9392c
TP
649config DMI
650 default y
651 bool "Enable DMI scanning" if EMBEDDED
8f9ca475 652 ---help---
7ae9392c
TP
653 Enabled scanning of DMI to identify machine quirks. Say Y
654 here unless you have verified that your setup is not
655 affected by entries in the DMI blacklist. Required by PNP
656 BIOS code.
657
506f1d07
SR
658config GART_IOMMU
659 bool "GART IOMMU support" if EMBEDDED
660 default y
661 select SWIOTLB
0e152cd7 662 depends on X86_64 && PCI && K8_NB
8f9ca475 663 ---help---
506f1d07
SR
664 Support for full DMA access of devices with 32bit memory access only
665 on systems with more than 3GB. This is usually needed for USB,
666 sound, many IDE/SATA chipsets and some other devices.
667 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
668 based hardware IOMMU and a software bounce buffer based IOMMU used
669 on Intel systems and as fallback.
670 The code is only active when needed (enough memory and limited
671 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
672 too.
673
674config CALGARY_IOMMU
675 bool "IBM Calgary IOMMU support"
676 select SWIOTLB
677 depends on X86_64 && PCI && EXPERIMENTAL
8f9ca475 678 ---help---
506f1d07
SR
679 Support for hardware IOMMUs in IBM's xSeries x366 and x460
680 systems. Needed to run systems with more than 3GB of memory
681 properly with 32-bit PCI devices that do not support DAC
682 (Double Address Cycle). Calgary also supports bus level
683 isolation, where all DMAs pass through the IOMMU. This
684 prevents them from going anywhere except their intended
685 destination. This catches hard-to-find kernel bugs and
686 mis-behaving drivers and devices that do not use the DMA-API
687 properly to set up their DMA buffers. The IOMMU can be
688 turned off at boot time with the iommu=off parameter.
689 Normally the kernel will make the right choice by itself.
690 If unsure, say Y.
691
692config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
693 def_bool y
694 prompt "Should Calgary be enabled by default?"
506f1d07 695 depends on CALGARY_IOMMU
8f9ca475 696 ---help---
506f1d07
SR
697 Should Calgary be enabled by default? if you choose 'y', Calgary
698 will be used (if it exists). If you choose 'n', Calgary will not be
699 used even if it exists. If you choose 'n' and would like to use
700 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
701 If unsure, say Y.
702
2b188723
JR
703config AMD_IOMMU
704 bool "AMD IOMMU support"
07c40e8a 705 select SWIOTLB
a80dc3e0 706 select PCI_MSI
24d2ba0a 707 depends on X86_64 && PCI && ACPI
8f9ca475 708 ---help---
18d22200
JR
709 With this option you can enable support for AMD IOMMU hardware in
710 your system. An IOMMU is a hardware component which provides
711 remapping of DMA memory accesses from devices. With an AMD IOMMU you
712 can isolate the the DMA memory of different devices and protect the
713 system from misbehaving device drivers or hardware.
714
715 You can find out if your system has an AMD IOMMU if you look into
716 your BIOS for an option to enable it or if you have an IVRS ACPI
717 table.
2b188723 718
2e117604
JR
719config AMD_IOMMU_STATS
720 bool "Export AMD IOMMU statistics to debugfs"
721 depends on AMD_IOMMU
722 select DEBUG_FS
8f9ca475 723 ---help---
2e117604
JR
724 This option enables code in the AMD IOMMU driver to collect various
725 statistics about whats happening in the driver and exports that
726 information to userspace via debugfs.
727 If unsure, say N.
728
506f1d07
SR
729# need this always selected by IOMMU for the VIA workaround
730config SWIOTLB
a1afd01c 731 def_bool y if X86_64
8f9ca475 732 ---help---
506f1d07
SR
733 Support for software bounce buffers used on x86-64 systems
734 which don't have a hardware IOMMU (e.g. the current generation
735 of Intel's x86-64 CPUs). Using this PCI devices which can only
736 access 32-bits of memory can be used on systems with more than
737 3 GB of memory. If unsure, say Y.
738
a8522509 739config IOMMU_HELPER
18b743dc 740 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
d25e26b6 741
1aaf1183
JR
742config IOMMU_API
743 def_bool (AMD_IOMMU || DMAR)
744
1184dc2f
MT
745config MAXSMP
746 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
36f5101a
MT
747 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
748 select CPUMASK_OFFSTACK
8f9ca475 749 ---help---
1184dc2f
MT
750 Configure maximum number of CPUS and NUMA Nodes for this architecture.
751 If unsure, say N.
506f1d07
SR
752
753config NR_CPUS
36f5101a 754 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 755 range 2 8 if SMP && X86_32 && !X86_BIGSMP
36f5101a 756 range 2 512 if SMP && !MAXSMP
78637a97 757 default "1" if !SMP
d25e26b6 758 default "4096" if MAXSMP
78637a97
MT
759 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
760 default "8" if SMP
8f9ca475 761 ---help---
506f1d07 762 This allows you to specify the maximum number of CPUs which this
d25e26b6 763 kernel will support. The maximum supported value is 512 and the
506f1d07
SR
764 minimum value which makes sense is 2.
765
766 This is purely to save memory - each supported CPU adds
767 approximately eight kilobytes to the kernel image.
768
769config SCHED_SMT
770 bool "SMT (Hyperthreading) scheduler support"
b089c12b 771 depends on X86_HT
8f9ca475 772 ---help---
506f1d07
SR
773 SMT scheduler support improves the CPU scheduler's decision making
774 when dealing with Intel Pentium 4 chips with HyperThreading at a
775 cost of slightly increased overhead in some places. If unsure say
776 N here.
777
778config SCHED_MC
3c2362e6
HH
779 def_bool y
780 prompt "Multi-core scheduler support"
b089c12b 781 depends on X86_HT
8f9ca475 782 ---help---
506f1d07
SR
783 Multi-core scheduler support improves the CPU scheduler's decision
784 making when dealing with multi-core CPU chips at a cost of slightly
785 increased overhead in some places. If unsure say N here.
786
787source "kernel/Kconfig.preempt"
788
789config X86_UP_APIC
790 bool "Local APIC support on uniprocessors"
e0c7ae37 791 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 792 ---help---
506f1d07
SR
793 A local APIC (Advanced Programmable Interrupt Controller) is an
794 integrated interrupt controller in the CPU. If you have a single-CPU
795 system which has a processor with a local APIC, you can say Y here to
796 enable and use it. If you say Y here even though your machine doesn't
797 have a local APIC, then the kernel will still run with no slowdown at
798 all. The local APIC supports CPU-generated self-interrupts (timer,
799 performance counters), and the NMI watchdog which detects hard
800 lockups.
801
802config X86_UP_IOAPIC
803 bool "IO-APIC support on uniprocessors"
804 depends on X86_UP_APIC
8f9ca475 805 ---help---
506f1d07
SR
806 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
807 SMP-capable replacement for PC-style interrupt controllers. Most
808 SMP systems and many recent uniprocessor systems have one.
809
810 If you have a single-CPU system with an IO-APIC, you can say Y here
811 to use it. If you say Y here even though your machine doesn't have
812 an IO-APIC, then the kernel will still run with no slowdown at all.
813
814config X86_LOCAL_APIC
3c2362e6 815 def_bool y
e0c7ae37 816 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
817
818config X86_IO_APIC
3c2362e6 819 def_bool y
e0c7ae37 820 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
821
822config X86_VISWS_APIC
3c2362e6 823 def_bool y
506f1d07 824 depends on X86_32 && X86_VISWS
506f1d07 825
41b9eb26
SA
826config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
827 bool "Reroute for broken boot IRQs"
41b9eb26 828 depends on X86_IO_APIC
8f9ca475 829 ---help---
41b9eb26
SA
830 This option enables a workaround that fixes a source of
831 spurious interrupts. This is recommended when threaded
832 interrupt handling is used on systems where the generation of
833 superfluous "boot interrupts" cannot be disabled.
834
835 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
836 entry in the chipset's IO-APIC is masked (as, e.g. the RT
837 kernel does during interrupt handling). On chipsets where this
838 boot IRQ generation cannot be disabled, this workaround keeps
839 the original IRQ line masked so that only the equivalent "boot
840 IRQ" is delivered to the CPUs. The workaround also tells the
841 kernel to set up the IRQ handler on the boot IRQ line. In this
842 way only one interrupt is delivered to the kernel. Otherwise
843 the spurious second interrupt may cause the kernel to bring
844 down (vital) interrupt lines.
845
846 Only affects "broken" chipsets. Interrupt sharing may be
847 increased on these systems.
848
506f1d07 849config X86_MCE
bab9bc65 850 bool "Machine Check / overheating reporting"
506f1d07 851 ---help---
bab9bc65
AK
852 Machine Check support allows the processor to notify the
853 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 854 The action the kernel takes depends on the severity of the problem,
bab9bc65 855 ranging from warning messages to halting the machine.
4efc0670 856
506f1d07 857config X86_MCE_INTEL
3c2362e6
HH
858 def_bool y
859 prompt "Intel MCE features"
c1ebf835 860 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 861 ---help---
506f1d07
SR
862 Additional support for intel specific MCE features such as
863 the thermal monitor.
864
865config X86_MCE_AMD
3c2362e6
HH
866 def_bool y
867 prompt "AMD MCE features"
c1ebf835 868 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 869 ---help---
506f1d07
SR
870 Additional support for AMD specific MCE features such as
871 the DRAM Error Threshold.
872
4efc0670 873config X86_ANCIENT_MCE
6fc108a0 874 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 875 depends on X86_32 && X86_MCE
cd13adcc
HS
876 ---help---
877 Include support for machine check handling on old Pentium 5 or WinChip
878 systems. These typically need to be enabled explicitely on the command
879 line.
4efc0670 880
b2762686
AK
881config X86_MCE_THRESHOLD
882 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 883 def_bool y
b2762686 884
ea149b36 885config X86_MCE_INJECT
c1ebf835 886 depends on X86_MCE
ea149b36
AK
887 tristate "Machine check injector support"
888 ---help---
889 Provide support for injecting machine checks for testing purposes.
890 If you don't know what a machine check is and you don't do kernel
891 QA it is safe to say n.
892
4efc0670
AK
893config X86_THERMAL_VECTOR
894 def_bool y
5bb38adc 895 depends on X86_MCE_INTEL
4efc0670 896
506f1d07
SR
897config VM86
898 bool "Enable VM86 support" if EMBEDDED
899 default y
900 depends on X86_32
8f9ca475
IM
901 ---help---
902 This option is required by programs like DOSEMU to run 16-bit legacy
506f1d07 903 code on X86 processors. It also may be needed by software like
8f9ca475
IM
904 XFree86 to initialize some video cards via BIOS. Disabling this
905 option saves about 6k.
506f1d07
SR
906
907config TOSHIBA
908 tristate "Toshiba Laptop support"
909 depends on X86_32
910 ---help---
911 This adds a driver to safely access the System Management Mode of
912 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
913 not work on models with a Phoenix BIOS. The System Management Mode
914 is used to set the BIOS and power saving options on Toshiba portables.
915
916 For information on utilities to make use of this driver see the
917 Toshiba Linux utilities web site at:
918 <http://www.buzzard.org.uk/toshiba/>.
919
920 Say Y if you intend to run this kernel on a Toshiba portable.
921 Say N otherwise.
922
923config I8K
924 tristate "Dell laptop support"
506f1d07
SR
925 ---help---
926 This adds a driver to safely access the System Management Mode
927 of the CPU on the Dell Inspiron 8000. The System Management Mode
928 is used to read cpu temperature and cooling fan status and to
929 control the fans on the I8K portables.
930
931 This driver has been tested only on the Inspiron 8000 but it may
932 also work with other Dell laptops. You can force loading on other
933 models by passing the parameter `force=1' to the module. Use at
934 your own risk.
935
936 For information on utilities to make use of this driver see the
937 I8K Linux utilities web site at:
938 <http://people.debian.org/~dz/i8k/>
939
940 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
941 Say N otherwise.
942
943config X86_REBOOTFIXUPS
9ba16087
JB
944 bool "Enable X86 board specific fixups for reboot"
945 depends on X86_32
506f1d07
SR
946 ---help---
947 This enables chipset and/or board specific fixups to be done
948 in order to get reboot to work correctly. This is only needed on
949 some combinations of hardware and BIOS. The symptom, for which
950 this config is intended, is when reboot ends with a stalled/hung
951 system.
952
953 Currently, the only fixup is for the Geode machines using
5e3a77e9 954 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
955
956 Say Y if you want to enable the fixup. Currently, it's safe to
957 enable this option even if you don't need it.
958 Say N otherwise.
959
960config MICROCODE
8d86f390 961 tristate "/dev/cpu/microcode - microcode support"
506f1d07
SR
962 select FW_LOADER
963 ---help---
964 If you say Y here, you will be able to update the microcode on
80cc9f10
PO
965 certain Intel and AMD processors. The Intel support is for the
966 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
967 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
968 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
969 You will obviously need the actual microcode binary data itself
970 which is not shipped with the Linux kernel.
506f1d07 971
8d86f390
PO
972 This option selects the general module only, you need to select
973 at least one vendor specific module as well.
506f1d07
SR
974
975 To compile this driver as a module, choose M here: the
976 module will be called microcode.
977
8d86f390 978config MICROCODE_INTEL
8f9ca475
IM
979 bool "Intel microcode patch loading support"
980 depends on MICROCODE
981 default MICROCODE
982 select FW_LOADER
983 ---help---
984 This options enables microcode patch loading support for Intel
985 processors.
986
987 For latest news and information on obtaining all the required
988 Intel ingredients for this driver, check:
989 <http://www.urbanmyth.org/microcode/>.
8d86f390 990
80cc9f10 991config MICROCODE_AMD
8f9ca475
IM
992 bool "AMD microcode patch loading support"
993 depends on MICROCODE
994 select FW_LOADER
995 ---help---
996 If you select this option, microcode patch loading support for AMD
997 processors will be enabled.
80cc9f10 998
8f9ca475 999config MICROCODE_OLD_INTERFACE
3c2362e6 1000 def_bool y
506f1d07 1001 depends on MICROCODE
506f1d07
SR
1002
1003config X86_MSR
1004 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1005 ---help---
506f1d07
SR
1006 This device gives privileged processes access to the x86
1007 Model-Specific Registers (MSRs). It is a character device with
1008 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1009 MSR accesses are directed to a specific CPU on multi-processor
1010 systems.
1011
1012config X86_CPUID
1013 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1014 ---help---
506f1d07
SR
1015 This device gives processes access to the x86 CPUID instruction to
1016 be executed on a specific processor. It is a character device
1017 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1018 /dev/cpu/31/cpuid.
1019
1020choice
1021 prompt "High Memory Support"
506f1d07 1022 default HIGHMEM64G if X86_NUMAQ
6fc108a0 1023 default HIGHMEM4G
506f1d07
SR
1024 depends on X86_32
1025
1026config NOHIGHMEM
1027 bool "off"
1028 depends on !X86_NUMAQ
1029 ---help---
1030 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1031 However, the address space of 32-bit x86 processors is only 4
1032 Gigabytes large. That means that, if you have a large amount of
1033 physical memory, not all of it can be "permanently mapped" by the
1034 kernel. The physical memory that's not permanently mapped is called
1035 "high memory".
1036
1037 If you are compiling a kernel which will never run on a machine with
1038 more than 1 Gigabyte total physical RAM, answer "off" here (default
1039 choice and suitable for most users). This will result in a "3GB/1GB"
1040 split: 3GB are mapped so that each process sees a 3GB virtual memory
1041 space and the remaining part of the 4GB virtual memory space is used
1042 by the kernel to permanently map as much physical memory as
1043 possible.
1044
1045 If the machine has between 1 and 4 Gigabytes physical RAM, then
1046 answer "4GB" here.
1047
1048 If more than 4 Gigabytes is used then answer "64GB" here. This
1049 selection turns Intel PAE (Physical Address Extension) mode on.
1050 PAE implements 3-level paging on IA32 processors. PAE is fully
1051 supported by Linux, PAE mode is implemented on all recent Intel
1052 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1053 then the kernel will not boot on CPUs that don't support PAE!
1054
1055 The actual amount of total physical memory will either be
1056 auto detected or can be forced by using a kernel command line option
1057 such as "mem=256M". (Try "man bootparam" or see the documentation of
1058 your boot loader (lilo or loadlin) about how to pass options to the
1059 kernel at boot time.)
1060
1061 If unsure, say "off".
1062
1063config HIGHMEM4G
1064 bool "4GB"
1065 depends on !X86_NUMAQ
8f9ca475 1066 ---help---
506f1d07
SR
1067 Select this if you have a 32-bit processor and between 1 and 4
1068 gigabytes of physical RAM.
1069
1070config HIGHMEM64G
1071 bool "64GB"
1072 depends on !M386 && !M486
1073 select X86_PAE
8f9ca475 1074 ---help---
506f1d07
SR
1075 Select this if you have a 32-bit processor and more than 4
1076 gigabytes of physical RAM.
1077
1078endchoice
1079
1080choice
1081 depends on EXPERIMENTAL
1082 prompt "Memory split" if EMBEDDED
1083 default VMSPLIT_3G
1084 depends on X86_32
8f9ca475 1085 ---help---
506f1d07
SR
1086 Select the desired split between kernel and user memory.
1087
1088 If the address range available to the kernel is less than the
1089 physical memory installed, the remaining memory will be available
1090 as "high memory". Accessing high memory is a little more costly
1091 than low memory, as it needs to be mapped into the kernel first.
1092 Note that increasing the kernel address space limits the range
1093 available to user programs, making the address space there
1094 tighter. Selecting anything other than the default 3G/1G split
1095 will also likely make your kernel incompatible with binary-only
1096 kernel modules.
1097
1098 If you are not absolutely sure what you are doing, leave this
1099 option alone!
1100
1101 config VMSPLIT_3G
1102 bool "3G/1G user/kernel split"
1103 config VMSPLIT_3G_OPT
1104 depends on !X86_PAE
1105 bool "3G/1G user/kernel split (for full 1G low memory)"
1106 config VMSPLIT_2G
1107 bool "2G/2G user/kernel split"
1108 config VMSPLIT_2G_OPT
1109 depends on !X86_PAE
1110 bool "2G/2G user/kernel split (for full 2G low memory)"
1111 config VMSPLIT_1G
1112 bool "1G/3G user/kernel split"
1113endchoice
1114
1115config PAGE_OFFSET
1116 hex
1117 default 0xB0000000 if VMSPLIT_3G_OPT
1118 default 0x80000000 if VMSPLIT_2G
1119 default 0x78000000 if VMSPLIT_2G_OPT
1120 default 0x40000000 if VMSPLIT_1G
1121 default 0xC0000000
1122 depends on X86_32
1123
1124config HIGHMEM
3c2362e6 1125 def_bool y
506f1d07 1126 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1127
1128config X86_PAE
9ba16087 1129 bool "PAE (Physical Address Extension) Support"
506f1d07 1130 depends on X86_32 && !HIGHMEM4G
8f9ca475 1131 ---help---
506f1d07
SR
1132 PAE is required for NX support, and furthermore enables
1133 larger swapspace support for non-overcommit purposes. It
1134 has the cost of more pagetable lookup overhead, and also
1135 consumes more pagetable space per process.
1136
600715dc 1137config ARCH_PHYS_ADDR_T_64BIT
8f9ca475 1138 def_bool X86_64 || X86_PAE
600715dc 1139
9e899816
NP
1140config DIRECT_GBPAGES
1141 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1142 default y
1143 depends on X86_64
8f9ca475 1144 ---help---
9e899816
NP
1145 Allow the kernel linear mapping to use 1GB pages on CPUs that
1146 support it. This can improve the kernel's performance a tiny bit by
1147 reducing TLB pressure. If in doubt, say "Y".
1148
506f1d07
SR
1149# Common NUMA Features
1150config NUMA
fd51b2d7 1151 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1152 depends on SMP
604d2055 1153 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
0699eae1 1154 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
8f9ca475 1155 ---help---
506f1d07 1156 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1157
506f1d07
SR
1158 The kernel will try to allocate memory used by a CPU on the
1159 local memory controller of the CPU and add some more
1160 NUMA awareness to the kernel.
1161
c280ea5e 1162 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1163 (or later), AMD Opteron, or EM64T NUMA.
1164
1165 For 32-bit this is only needed on (rare) 32-bit-only platforms
1166 that support NUMA topologies, such as NUMAQ / Summit, or if you
1167 boot a 32-bit kernel on a 64-bit NUMA platform.
1168
1169 Otherwise, you should say N.
506f1d07
SR
1170
1171comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1172 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1173
1174config K8_NUMA
3c2362e6
HH
1175 def_bool y
1176 prompt "Old style AMD Opteron NUMA detection"
1177 depends on X86_64 && NUMA && PCI
8f9ca475
IM
1178 ---help---
1179 Enable K8 NUMA node topology detection. You should say Y here if
1180 you have a multi processor AMD K8 system. This uses an old
1181 method to read the NUMA configuration directly from the builtin
1182 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1183 instead, which also takes priority if both are compiled in.
506f1d07
SR
1184
1185config X86_64_ACPI_NUMA
3c2362e6
HH
1186 def_bool y
1187 prompt "ACPI NUMA detection"
506f1d07
SR
1188 depends on X86_64 && NUMA && ACPI && PCI
1189 select ACPI_NUMA
8f9ca475 1190 ---help---
506f1d07
SR
1191 Enable ACPI SRAT based node topology detection.
1192
6ec6e0d9
SS
1193# Some NUMA nodes have memory ranges that span
1194# other nodes. Even though a pfn is valid and
1195# between a node's start and end pfns, it may not
1196# reside on that node. See memmap_init_zone()
1197# for details.
1198config NODES_SPAN_OTHER_NODES
1199 def_bool y
1200 depends on X86_64_ACPI_NUMA
1201
506f1d07
SR
1202config NUMA_EMU
1203 bool "NUMA emulation"
1204 depends on X86_64 && NUMA
8f9ca475 1205 ---help---
506f1d07
SR
1206 Enable NUMA emulation. A flat machine will be split
1207 into virtual nodes when booted with "numa=fake=N", where N is the
1208 number of nodes. This is only useful for debugging.
1209
1210config NODES_SHIFT
d25e26b6 1211 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1212 range 1 10
1213 default "10" if MAXSMP
506f1d07
SR
1214 default "6" if X86_64
1215 default "4" if X86_NUMAQ
1216 default "3"
1217 depends on NEED_MULTIPLE_NODES
8f9ca475 1218 ---help---
1184dc2f 1219 Specify the maximum number of NUMA Nodes available on the target
692105b8 1220 system. Increases memory reserved to accommodate various tables.
506f1d07 1221
c1329375 1222config HAVE_ARCH_BOOTMEM
3c2362e6 1223 def_bool y
506f1d07 1224 depends on X86_32 && NUMA
506f1d07
SR
1225
1226config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1227 def_bool y
506f1d07 1228 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1229
1230config NEED_NODE_MEMMAP_SIZE
3c2362e6 1231 def_bool y
506f1d07 1232 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07
SR
1233
1234config HAVE_ARCH_ALLOC_REMAP
3c2362e6 1235 def_bool y
506f1d07 1236 depends on X86_32 && NUMA
506f1d07
SR
1237
1238config ARCH_FLATMEM_ENABLE
1239 def_bool y
99809963 1240 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
506f1d07
SR
1241
1242config ARCH_DISCONTIGMEM_ENABLE
1243 def_bool y
b263295d 1244 depends on NUMA && X86_32
506f1d07
SR
1245
1246config ARCH_DISCONTIGMEM_DEFAULT
1247 def_bool y
b263295d
CL
1248 depends on NUMA && X86_32
1249
9492587c
KH
1250config ARCH_PROC_KCORE_TEXT
1251 def_bool y
1252 depends on X86_64 && PROC_KCORE
1253
b263295d
CL
1254config ARCH_SPARSEMEM_DEFAULT
1255 def_bool y
1256 depends on X86_64
506f1d07
SR
1257
1258config ARCH_SPARSEMEM_ENABLE
1259 def_bool y
4272ebfb 1260 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
506f1d07
SR
1261 select SPARSEMEM_STATIC if X86_32
1262 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1263
1264config ARCH_SELECT_MEMORY_MODEL
1265 def_bool y
b263295d 1266 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1267
1268config ARCH_MEMORY_PROBE
1269 def_bool X86_64
1270 depends on MEMORY_HOTPLUG
1271
a29815a3
AK
1272config ILLEGAL_POINTER_VALUE
1273 hex
1274 default 0 if X86_32
1275 default 0xdead000000000000 if X86_64
1276
506f1d07
SR
1277source "mm/Kconfig"
1278
1279config HIGHPTE
1280 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1281 depends on HIGHMEM
8f9ca475 1282 ---help---
506f1d07
SR
1283 The VM uses one page table entry for each page of physical memory.
1284 For systems with a lot of RAM, this can be wasteful of precious
1285 low memory. Setting this option will put user-space page table
1286 entries in high memory.
1287
9f077871 1288config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1289 bool "Check for low memory corruption"
1290 ---help---
1291 Periodically check for memory corruption in low memory, which
1292 is suspected to be caused by BIOS. Even when enabled in the
1293 configuration, it is disabled at runtime. Enable it by
1294 setting "memory_corruption_check=1" on the kernel command
1295 line. By default it scans the low 64k of memory every 60
1296 seconds; see the memory_corruption_check_size and
1297 memory_corruption_check_period parameters in
1298 Documentation/kernel-parameters.txt to adjust this.
1299
1300 When enabled with the default parameters, this option has
1301 almost no overhead, as it reserves a relatively small amount
1302 of memory and scans it infrequently. It both detects corruption
1303 and prevents it from affecting the running system.
1304
1305 It is, however, intended as a diagnostic tool; if repeatable
1306 BIOS-originated corruption always affects the same memory,
1307 you can use memmap= to prevent the kernel from using that
1308 memory.
9f077871 1309
c885df50 1310config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1311 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1312 depends on X86_CHECK_BIOS_CORRUPTION
1313 default y
8f9ca475
IM
1314 ---help---
1315 Set whether the default state of memory_corruption_check is
1316 on or off.
c885df50 1317
fc381519 1318config X86_RESERVE_LOW_64K
8f9ca475 1319 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
fc381519 1320 default y
8f9ca475
IM
1321 ---help---
1322 Reserve the first 64K of physical RAM on BIOSes that are known
1323 to potentially corrupt that memory range. A numbers of BIOSes are
1324 known to utilize this area during suspend/resume, so it must not
1325 be used by the kernel.
fc381519 1326
8f9ca475
IM
1327 Set this to N if you are absolutely sure that you trust the BIOS
1328 to get all its memory reservations and usages right.
fc381519 1329
8f9ca475
IM
1330 If you have doubts about the BIOS (e.g. suspend/resume does not
1331 work or there's kernel crashes after certain hardware hotplug
1332 events) and it's not AMI or Phoenix, then you might want to enable
1333 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1334 corruption patterns.
fc381519 1335
8f9ca475 1336 Say Y if unsure.
fc381519 1337
506f1d07
SR
1338config MATH_EMULATION
1339 bool
1340 prompt "Math emulation" if X86_32
1341 ---help---
1342 Linux can emulate a math coprocessor (used for floating point
1343 operations) if you don't have one. 486DX and Pentium processors have
1344 a math coprocessor built in, 486SX and 386 do not, unless you added
1345 a 487DX or 387, respectively. (The messages during boot time can
1346 give you some hints here ["man dmesg"].) Everyone needs either a
1347 coprocessor or this emulation.
1348
1349 If you don't have a math coprocessor, you need to say Y here; if you
1350 say Y here even though you have a coprocessor, the coprocessor will
1351 be used nevertheless. (This behavior can be changed with the kernel
1352 command line option "no387", which comes handy if your coprocessor
1353 is broken. Try "man bootparam" or see the documentation of your boot
1354 loader (lilo or loadlin) about how to pass options to the kernel at
1355 boot time.) This means that it is a good idea to say Y here if you
1356 intend to use this kernel on different machines.
1357
1358 More information about the internals of the Linux math coprocessor
1359 emulation can be found in <file:arch/x86/math-emu/README>.
1360
1361 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1362 kernel, it won't hurt.
1363
1364config MTRR
6fc108a0 1365 def_bool y
c03cb314 1366 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
506f1d07
SR
1367 ---help---
1368 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1369 the Memory Type Range Registers (MTRRs) may be used to control
1370 processor access to memory ranges. This is most useful if you have
1371 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1372 allows bus write transfers to be combined into a larger transfer
1373 before bursting over the PCI/AGP bus. This can increase performance
1374 of image write operations 2.5 times or more. Saying Y here creates a
1375 /proc/mtrr file which may be used to manipulate your processor's
1376 MTRRs. Typically the X server should use this.
1377
1378 This code has a reasonably generic interface so that similar
1379 control registers on other processors can be easily supported
1380 as well:
1381
1382 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1383 Registers (ARRs) which provide a similar functionality to MTRRs. For
1384 these, the ARRs are used to emulate the MTRRs.
1385 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1386 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1387 write-combining. All of these processors are supported by this code
1388 and it makes sense to say Y here if you have one of them.
1389
1390 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1391 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1392 can lead to all sorts of problems, so it's good to say Y here.
1393
1394 You can safely say Y even if your machine doesn't have MTRRs, you'll
1395 just add about 9 KB to your kernel.
1396
7225e751 1397 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1398
95ffa243 1399config MTRR_SANITIZER
2ffb3501 1400 def_bool y
95ffa243
YL
1401 prompt "MTRR cleanup support"
1402 depends on MTRR
8f9ca475 1403 ---help---
aba3728c
TG
1404 Convert MTRR layout from continuous to discrete, so X drivers can
1405 add writeback entries.
95ffa243 1406
aba3728c 1407 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1408 The largest mtrr entry size for a continuous block can be set with
aba3728c 1409 mtrr_chunk_size.
95ffa243 1410
2ffb3501 1411 If unsure, say Y.
95ffa243
YL
1412
1413config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1414 int "MTRR cleanup enable value (0-1)"
1415 range 0 1
1416 default "0"
95ffa243 1417 depends on MTRR_SANITIZER
8f9ca475 1418 ---help---
f5098d62 1419 Enable mtrr cleanup default value
95ffa243 1420
12031a62
YL
1421config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1422 int "MTRR cleanup spare reg num (0-7)"
1423 range 0 7
1424 default "1"
1425 depends on MTRR_SANITIZER
8f9ca475 1426 ---help---
12031a62 1427 mtrr cleanup spare entries default, it can be changed via
aba3728c 1428 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1429
2e5d9c85 1430config X86_PAT
6fc108a0 1431 def_bool y
c03cb314 1432 prompt "x86 PAT support" if EMBEDDED
2a8a2719 1433 depends on MTRR
8f9ca475 1434 ---help---
2e5d9c85 1435 Use PAT attributes to setup page level cache control.
042b78e4 1436
2e5d9c85 1437 PATs are the modern equivalents of MTRRs and are much more
1438 flexible than MTRRs.
1439
1440 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1441 spontaneous reboots) or a non-working video driver.
2e5d9c85 1442
1443 If unsure, say Y.
1444
46cf98cd
VP
1445config ARCH_USES_PG_UNCACHED
1446 def_bool y
1447 depends on X86_PAT
1448
506f1d07 1449config EFI
9ba16087 1450 bool "EFI runtime service support"
5b83683f 1451 depends on ACPI
506f1d07 1452 ---help---
8f9ca475
IM
1453 This enables the kernel to use EFI runtime services that are
1454 available (such as the EFI variable services).
506f1d07 1455
8f9ca475
IM
1456 This option is only useful on systems that have EFI firmware.
1457 In addition, you should use the latest ELILO loader available
1458 at <http://elilo.sourceforge.net> in order to take advantage
1459 of EFI runtime services. However, even with this option, the
1460 resultant kernel should continue to boot on existing non-EFI
1461 platforms.
506f1d07 1462
506f1d07 1463config SECCOMP
3c2362e6
HH
1464 def_bool y
1465 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1466 ---help---
506f1d07
SR
1467 This kernel feature is useful for number crunching applications
1468 that may need to compute untrusted bytecode during their
1469 execution. By using pipes or other transports made available to
1470 the process as file descriptors supporting the read/write
1471 syscalls, it's possible to isolate those applications in
1472 their own address space using seccomp. Once seccomp is
9c0bbee8 1473 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1474 and the task is only allowed to execute a few safe syscalls
1475 defined by each seccomp mode.
1476
1477 If unsure, say Y. Only embedded should say N here.
1478
1479config CC_STACKPROTECTOR
1480 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
8f9ca475
IM
1481 ---help---
1482 This option turns on the -fstack-protector GCC feature. This
113c5413
IM
1483 feature puts, at the beginning of functions, a canary value on
1484 the stack just before the return address, and validates
506f1d07
SR
1485 the value just before actually returning. Stack based buffer
1486 overflows (that need to overwrite this return address) now also
1487 overwrite the canary, which gets detected and the attack is then
1488 neutralized via a kernel panic.
1489
1490 This feature requires gcc version 4.2 or above, or a distribution
1491 gcc with the feature backported. Older versions are automatically
113c5413
IM
1492 detected and for those versions, this configuration option is
1493 ignored. (and a warning is printed during bootup)
506f1d07
SR
1494
1495source kernel/Kconfig.hz
1496
1497config KEXEC
1498 bool "kexec system call"
8f9ca475 1499 ---help---
506f1d07
SR
1500 kexec is a system call that implements the ability to shutdown your
1501 current kernel, and to start another kernel. It is like a reboot
1502 but it is independent of the system firmware. And like a reboot
1503 you can start any kernel with it, not just Linux.
1504
1505 The name comes from the similarity to the exec system call.
1506
1507 It is an ongoing process to be certain the hardware in a machine
1508 is properly shutdown, so do not be surprised if this code does not
1509 initially work for you. It may help to enable device hotplugging
1510 support. As of this writing the exact hardware interface is
1511 strongly in flux, so no good recommendation can be made.
1512
1513config CRASH_DUMP
04b69447 1514 bool "kernel crash dumps"
506f1d07 1515 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1516 ---help---
506f1d07
SR
1517 Generate crash dump after being started by kexec.
1518 This should be normally only set in special crash dump kernels
1519 which are loaded in the main kernel with kexec-tools into
1520 a specially reserved region and then later executed after
1521 a crash by kdump/kexec. The crash dump kernel must be compiled
1522 to a memory address not used by the main kernel or BIOS using
1523 PHYSICAL_START, or it must be built as a relocatable image
1524 (CONFIG_RELOCATABLE=y).
1525 For more details see Documentation/kdump/kdump.txt
1526
3ab83521
HY
1527config KEXEC_JUMP
1528 bool "kexec jump (EXPERIMENTAL)"
1529 depends on EXPERIMENTAL
fee7b0d8 1530 depends on KEXEC && HIBERNATION
8f9ca475 1531 ---help---
89081d17
HY
1532 Jump between original kernel and kexeced kernel and invoke
1533 code in physical address mode via KEXEC
3ab83521 1534
506f1d07
SR
1535config PHYSICAL_START
1536 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
ceefccc9 1537 default "0x1000000"
8f9ca475 1538 ---help---
506f1d07
SR
1539 This gives the physical address where the kernel is loaded.
1540
1541 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1542 bzImage will decompress itself to above physical address and
1543 run from there. Otherwise, bzImage will run from the address where
1544 it has been loaded by the boot loader and will ignore above physical
1545 address.
1546
1547 In normal kdump cases one does not have to set/change this option
1548 as now bzImage can be compiled as a completely relocatable image
1549 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1550 address. This option is mainly useful for the folks who don't want
1551 to use a bzImage for capturing the crash dump and want to use a
1552 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1553 to be specifically compiled to run from a specific memory area
1554 (normally a reserved region) and this option comes handy.
1555
ceefccc9
PA
1556 So if you are using bzImage for capturing the crash dump,
1557 leave the value here unchanged to 0x1000000 and set
1558 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1559 for capturing the crash dump change this value to start of
1560 the reserved region. In other words, it can be set based on
1561 the "X" value as specified in the "crashkernel=YM@XM"
1562 command line boot parameter passed to the panic-ed
1563 kernel. Please take a look at Documentation/kdump/kdump.txt
1564 for more details about crash dumps.
506f1d07
SR
1565
1566 Usage of bzImage for capturing the crash dump is recommended as
1567 one does not have to build two kernels. Same kernel can be used
1568 as production kernel and capture kernel. Above option should have
1569 gone away after relocatable bzImage support is introduced. But it
1570 is present because there are users out there who continue to use
1571 vmlinux for dump capture. This option should go away down the
1572 line.
1573
1574 Don't change this unless you know what you are doing.
1575
1576config RELOCATABLE
26717808
PA
1577 bool "Build a relocatable kernel"
1578 default y
8f9ca475 1579 ---help---
506f1d07
SR
1580 This builds a kernel image that retains relocation information
1581 so it can be loaded someplace besides the default 1MB.
1582 The relocations tend to make the kernel binary about 10% larger,
1583 but are discarded at runtime.
1584
1585 One use is for the kexec on panic case where the recovery kernel
1586 must live at a different physical address than the primary
1587 kernel.
1588
1589 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1590 it has been loaded at and the compile time physical address
1591 (CONFIG_PHYSICAL_START) is ignored.
1592
845adf72
PA
1593# Relocation on x86-32 needs some additional build support
1594config X86_NEED_RELOCS
1595 def_bool y
1596 depends on X86_32 && RELOCATABLE
1597
506f1d07 1598config PHYSICAL_ALIGN
6fc108a0 1599 hex "Alignment value to which kernel should be aligned" if X86_32
ceefccc9
PA
1600 default "0x1000000"
1601 range 0x2000 0x1000000
8f9ca475 1602 ---help---
506f1d07
SR
1603 This value puts the alignment restrictions on physical address
1604 where kernel is loaded and run from. Kernel is compiled for an
1605 address which meets above alignment restriction.
1606
1607 If bootloader loads the kernel at a non-aligned address and
1608 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1609 address aligned to above value and run from there.
1610
1611 If bootloader loads the kernel at a non-aligned address and
1612 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1613 load address and decompress itself to the address it has been
1614 compiled for and run from there. The address for which kernel is
1615 compiled already meets above alignment restrictions. Hence the
1616 end result is that kernel runs from a physical address meeting
1617 above alignment restrictions.
1618
1619 Don't change this unless you know what you are doing.
1620
1621config HOTPLUG_CPU
7c13e6a3 1622 bool "Support for hot-pluggable CPUs"
4b19ed91 1623 depends on SMP && HOTPLUG
506f1d07 1624 ---help---
7c13e6a3
DS
1625 Say Y here to allow turning CPUs off and on. CPUs can be
1626 controlled through /sys/devices/system/cpu.
1627 ( Note: power management support will enable this option
1628 automatically on SMP systems. )
1629 Say N if you want to disable CPU hotplug.
506f1d07
SR
1630
1631config COMPAT_VDSO
3c2362e6
HH
1632 def_bool y
1633 prompt "Compat VDSO support"
af65d648 1634 depends on X86_32 || IA32_EMULATION
8f9ca475 1635 ---help---
af65d648 1636 Map the 32-bit VDSO to the predictable old-style address too.
e84446de 1637
506f1d07
SR
1638 Say N here if you are running a sufficiently recent glibc
1639 version (2.3.3 or later), to remove the high-mapped
1640 VDSO mapping and to exclusively use the randomized VDSO.
1641
1642 If unsure, say Y.
1643
516cbf37
TB
1644config CMDLINE_BOOL
1645 bool "Built-in kernel command line"
8f9ca475 1646 ---help---
516cbf37
TB
1647 Allow for specifying boot arguments to the kernel at
1648 build time. On some systems (e.g. embedded ones), it is
1649 necessary or convenient to provide some or all of the
1650 kernel boot arguments with the kernel itself (that is,
1651 to not rely on the boot loader to provide them.)
1652
1653 To compile command line arguments into the kernel,
1654 set this option to 'Y', then fill in the
1655 the boot arguments in CONFIG_CMDLINE.
1656
1657 Systems with fully functional boot loaders (i.e. non-embedded)
1658 should leave this option set to 'N'.
1659
1660config CMDLINE
1661 string "Built-in kernel command string"
1662 depends on CMDLINE_BOOL
1663 default ""
8f9ca475 1664 ---help---
516cbf37
TB
1665 Enter arguments here that should be compiled into the kernel
1666 image and used at boot time. If the boot loader provides a
1667 command line at boot time, it is appended to this string to
1668 form the full kernel command line, when the system boots.
1669
1670 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1671 change this behavior.
1672
1673 In most cases, the command line (whether built-in or provided
1674 by the boot loader) should specify the device for the root
1675 file system.
1676
1677config CMDLINE_OVERRIDE
1678 bool "Built-in command line overrides boot loader arguments"
516cbf37 1679 depends on CMDLINE_BOOL
8f9ca475 1680 ---help---
516cbf37
TB
1681 Set this option to 'Y' to have the kernel ignore the boot loader
1682 command line, and use ONLY the built-in command line.
1683
1684 This is used to work around broken boot loaders. This should
1685 be set to 'N' under normal conditions.
1686
506f1d07
SR
1687endmenu
1688
1689config ARCH_ENABLE_MEMORY_HOTPLUG
1690 def_bool y
1691 depends on X86_64 || (X86_32 && HIGHMEM)
1692
35551053
GH
1693config ARCH_ENABLE_MEMORY_HOTREMOVE
1694 def_bool y
1695 depends on MEMORY_HOTPLUG
1696
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SR
1697config HAVE_ARCH_EARLY_PFN_TO_NID
1698 def_bool X86_64
1699 depends on NUMA
1700
da85f865 1701menu "Power management and ACPI options"
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SR
1702
1703config ARCH_HIBERNATION_HEADER
3c2362e6 1704 def_bool y
e279b6c1 1705 depends on X86_64 && HIBERNATION
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1706
1707source "kernel/power/Kconfig"
1708
1709source "drivers/acpi/Kconfig"
1710
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FT
1711source "drivers/sfi/Kconfig"
1712
a6b68076 1713config X86_APM_BOOT
6fc108a0 1714 def_bool y
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1715 depends on APM || APM_MODULE
1716
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SR
1717menuconfig APM
1718 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 1719 depends on X86_32 && PM_SLEEP
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1720 ---help---
1721 APM is a BIOS specification for saving power using several different
1722 techniques. This is mostly useful for battery powered laptops with
1723 APM compliant BIOSes. If you say Y here, the system time will be
1724 reset after a RESUME operation, the /proc/apm device will provide
1725 battery status information, and user-space programs will receive
1726 notification of APM "events" (e.g. battery status change).
1727
1728 If you select "Y" here, you can disable actual use of the APM
1729 BIOS by passing the "apm=off" option to the kernel at boot time.
1730
1731 Note that the APM support is almost completely disabled for
1732 machines with more than one CPU.
1733
1734 In order to use APM, you will need supporting software. For location
53471121 1735 and more information, read <file:Documentation/power/pm.txt> and the
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SR
1736 Battery Powered Linux mini-HOWTO, available from
1737 <http://www.tldp.org/docs.html#howto>.
1738
1739 This driver does not spin down disk drives (see the hdparm(8)
1740 manpage ("man 8 hdparm") for that), and it doesn't turn off
1741 VESA-compliant "green" monitors.
1742
1743 This driver does not support the TI 4000M TravelMate and the ACER
1744 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1745 desktop machines also don't have compliant BIOSes, and this driver
1746 may cause those machines to panic during the boot phase.
1747
1748 Generally, if you don't have a battery in your machine, there isn't
1749 much point in using this driver and you should say N. If you get
1750 random kernel OOPSes or reboots that don't seem to be related to
1751 anything, try disabling/enabling this option (or disabling/enabling
1752 APM in your BIOS).
1753
1754 Some other things you should try when experiencing seemingly random,
1755 "weird" problems:
1756
1757 1) make sure that you have enough swap space and that it is
1758 enabled.
1759 2) pass the "no-hlt" option to the kernel
1760 3) switch on floating point emulation in the kernel and pass
1761 the "no387" option to the kernel
1762 4) pass the "floppy=nodma" option to the kernel
1763 5) pass the "mem=4M" option to the kernel (thereby disabling
1764 all but the first 4 MB of RAM)
1765 6) make sure that the CPU is not over clocked.
1766 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1767 8) disable the cache from your BIOS settings
1768 9) install a fan for the video card or exchange video RAM
1769 10) install a better fan for the CPU
1770 11) exchange RAM chips
1771 12) exchange the motherboard.
1772
1773 To compile this driver as a module, choose M here: the
1774 module will be called apm.
1775
1776if APM
1777
1778config APM_IGNORE_USER_SUSPEND
1779 bool "Ignore USER SUSPEND"
8f9ca475 1780 ---help---
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1781 This option will ignore USER SUSPEND requests. On machines with a
1782 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1783 series notebooks, it is necessary to say Y because of a BIOS bug.
1784
1785config APM_DO_ENABLE
1786 bool "Enable PM at boot time"
1787 ---help---
1788 Enable APM features at boot time. From page 36 of the APM BIOS
1789 specification: "When disabled, the APM BIOS does not automatically
1790 power manage devices, enter the Standby State, enter the Suspend
1791 State, or take power saving steps in response to CPU Idle calls."
1792 This driver will make CPU Idle calls when Linux is idle (unless this
1793 feature is turned off -- see "Do CPU IDLE calls", below). This
1794 should always save battery power, but more complicated APM features
1795 will be dependent on your BIOS implementation. You may need to turn
1796 this option off if your computer hangs at boot time when using APM
1797 support, or if it beeps continuously instead of suspending. Turn
1798 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1799 T400CDT. This is off by default since most machines do fine without
1800 this feature.
1801
1802config APM_CPU_IDLE
1803 bool "Make CPU Idle calls when idle"
8f9ca475 1804 ---help---
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SR
1805 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1806 On some machines, this can activate improved power savings, such as
1807 a slowed CPU clock rate, when the machine is idle. These idle calls
1808 are made after the idle loop has run for some length of time (e.g.,
1809 333 mS). On some machines, this will cause a hang at boot time or
1810 whenever the CPU becomes idle. (On machines with more than one CPU,
1811 this option does nothing.)
1812
1813config APM_DISPLAY_BLANK
1814 bool "Enable console blanking using APM"
8f9ca475 1815 ---help---
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SR
1816 Enable console blanking using the APM. Some laptops can use this to
1817 turn off the LCD backlight when the screen blanker of the Linux
1818 virtual console blanks the screen. Note that this is only used by
1819 the virtual console screen blanker, and won't turn off the backlight
1820 when using the X Window system. This also doesn't have anything to
1821 do with your VESA-compliant power-saving monitor. Further, this
1822 option doesn't work for all laptops -- it might not turn off your
1823 backlight at all, or it might print a lot of errors to the console,
1824 especially if you are using gpm.
1825
1826config APM_ALLOW_INTS
1827 bool "Allow interrupts during APM BIOS calls"
8f9ca475 1828 ---help---
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SR
1829 Normally we disable external interrupts while we are making calls to
1830 the APM BIOS as a measure to lessen the effects of a badly behaving
1831 BIOS implementation. The BIOS should reenable interrupts if it
1832 needs to. Unfortunately, some BIOSes do not -- especially those in
1833 many of the newer IBM Thinkpads. If you experience hangs when you
1834 suspend, try setting this to Y. Otherwise, say N.
1835
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SR
1836endif # APM
1837
1838source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1839
1840source "drivers/cpuidle/Kconfig"
1841
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AH
1842source "drivers/idle/Kconfig"
1843
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SR
1844endmenu
1845
1846
1847menu "Bus options (PCI etc.)"
1848
1849config PCI
1ac97018 1850 bool "PCI support"
1c858087 1851 default y
e279b6c1 1852 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
8f9ca475 1853 ---help---
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SR
1854 Find out whether you have a PCI motherboard. PCI is the name of a
1855 bus system, i.e. the way the CPU talks to the other stuff inside
1856 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1857 VESA. If you have PCI, say Y, otherwise N.
1858
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SR
1859choice
1860 prompt "PCI access mode"
efefa6f6 1861 depends on X86_32 && PCI
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SR
1862 default PCI_GOANY
1863 ---help---
1864 On PCI systems, the BIOS can be used to detect the PCI devices and
1865 determine their configuration. However, some old PCI motherboards
1866 have BIOS bugs and may crash if this is done. Also, some embedded
1867 PCI-based systems don't have any BIOS at all. Linux can also try to
1868 detect the PCI hardware directly without using the BIOS.
1869
1870 With this option, you can specify how Linux should detect the
1871 PCI devices. If you choose "BIOS", the BIOS will be used,
1872 if you choose "Direct", the BIOS won't be used, and if you
1873 choose "MMConfig", then PCI Express MMCONFIG will be used.
1874 If you choose "Any", the kernel will try MMCONFIG, then the
1875 direct access method and falls back to the BIOS if that doesn't
1876 work. If unsure, go with the default, which is "Any".
1877
1878config PCI_GOBIOS
1879 bool "BIOS"
1880
1881config PCI_GOMMCONFIG
1882 bool "MMConfig"
1883
1884config PCI_GODIRECT
1885 bool "Direct"
1886
3ef0e1f8
AS
1887config PCI_GOOLPC
1888 bool "OLPC"
1889 depends on OLPC
1890
2bdd1b03
AS
1891config PCI_GOANY
1892 bool "Any"
1893
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SR
1894endchoice
1895
1896config PCI_BIOS
3c2362e6 1897 def_bool y
efefa6f6 1898 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
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1899
1900# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1901config PCI_DIRECT
3c2362e6 1902 def_bool y
efefa6f6 1903 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
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SR
1904
1905config PCI_MMCONFIG
3c2362e6 1906 def_bool y
5f0db7a2 1907 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 1908
3ef0e1f8 1909config PCI_OLPC
2bdd1b03
AS
1910 def_bool y
1911 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 1912
e279b6c1 1913config PCI_DOMAINS
3c2362e6 1914 def_bool y
e279b6c1 1915 depends on PCI
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SR
1916
1917config PCI_MMCONFIG
1918 bool "Support mmconfig PCI config space access"
1919 depends on X86_64 && PCI && ACPI
1920
1921config DMAR
1922 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
4cf2e75d 1923 depends on PCI_MSI && ACPI && EXPERIMENTAL
e279b6c1
SR
1924 help
1925 DMA remapping (DMAR) devices support enables independent address
1926 translations for Direct Memory Access (DMA) from devices.
1927 These DMA remapping devices are reported via ACPI tables
1928 and include PCI device scope covered by these DMA
1929 remapping devices.
1930
0cd5c3c8 1931config DMAR_DEFAULT_ON
f6be37fd 1932 def_bool y
0cd5c3c8
KM
1933 prompt "Enable DMA Remapping Devices by default"
1934 depends on DMAR
1935 help
1936 Selecting this option will enable a DMAR device at boot time if
1937 one is found. If this option is not selected, DMAR support can
1938 be enabled by passing intel_iommu=on to the kernel. It is
1939 recommended you say N here while the DMAR code remains
1940 experimental.
1941
62edf5dc 1942config DMAR_BROKEN_GFX_WA
6fc108a0 1943 bool "Workaround broken graphics drivers (going away soon)"
0c02a20f 1944 depends on DMAR && BROKEN
62edf5dc
DW
1945 ---help---
1946 Current Graphics drivers tend to use physical address
1947 for DMA and avoid using DMA APIs. Setting this config
1948 option permits the IOMMU driver to set a unity map for
1949 all the OS-visible memory. Hence the driver can continue
1950 to use physical addresses for DMA, at least until this
1951 option is removed in the 2.6.32 kernel.
1952
e279b6c1 1953config DMAR_FLOPPY_WA
3c2362e6 1954 def_bool y
e279b6c1 1955 depends on DMAR
8f9ca475 1956 ---help---
c7ab48d2 1957 Floppy disk drivers are known to bypass DMA API calls
8f9ca475
IM
1958 thereby failing to work when IOMMU is enabled. This
1959 workaround will setup a 1:1 mapping for the first
c7ab48d2 1960 16MiB to make floppy (an ISA device) work.
e279b6c1 1961
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SS
1962config INTR_REMAP
1963 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1964 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
8f9ca475
IM
1965 ---help---
1966 Supports Interrupt remapping for IO-APIC and MSI devices.
1967 To use x2apic mode in the CPU's which support x2APIC enhancements or
1968 to support platforms with CPU's having > 8 bit APIC ID, say Y.
9fa8c481 1969
e279b6c1
SR
1970source "drivers/pci/pcie/Kconfig"
1971
1972source "drivers/pci/Kconfig"
1973
1974# x86_64 have no ISA slots, but do have ISA-style DMA.
1975config ISA_DMA_API
3c2362e6 1976 def_bool y
e279b6c1
SR
1977
1978if X86_32
1979
1980config ISA
1981 bool "ISA support"
8f9ca475 1982 ---help---
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SR
1983 Find out whether you have ISA slots on your motherboard. ISA is the
1984 name of a bus system, i.e. the way the CPU talks to the other stuff
1985 inside your box. Other bus systems are PCI, EISA, MicroChannel
1986 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1987 newer boards don't support it. If you have ISA, say Y, otherwise N.
1988
1989config EISA
1990 bool "EISA support"
1991 depends on ISA
1992 ---help---
1993 The Extended Industry Standard Architecture (EISA) bus was
1994 developed as an open alternative to the IBM MicroChannel bus.
1995
1996 The EISA bus provided some of the features of the IBM MicroChannel
1997 bus while maintaining backward compatibility with cards made for
1998 the older ISA bus. The EISA bus saw limited use between 1988 and
1999 1995 when it was made obsolete by the PCI bus.
2000
2001 Say Y here if you are building a kernel for an EISA-based machine.
2002
2003 Otherwise, say N.
2004
2005source "drivers/eisa/Kconfig"
2006
2007config MCA
72ee6ebb 2008 bool "MCA support"
8f9ca475 2009 ---help---
e279b6c1
SR
2010 MicroChannel Architecture is found in some IBM PS/2 machines and
2011 laptops. It is a bus system similar to PCI or ISA. See
2012 <file:Documentation/mca.txt> (and especially the web page given
2013 there) before attempting to build an MCA bus kernel.
2014
2015source "drivers/mca/Kconfig"
2016
2017config SCx200
2018 tristate "NatSemi SCx200 support"
8f9ca475 2019 ---help---
e279b6c1
SR
2020 This provides basic support for National Semiconductor's
2021 (now AMD's) Geode processors. The driver probes for the
2022 PCI-IDs of several on-chip devices, so its a good dependency
2023 for other scx200_* drivers.
2024
2025 If compiled as a module, the driver is named scx200.
2026
2027config SCx200HR_TIMER
2028 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2029 depends on SCx200 && GENERIC_TIME
2030 default y
8f9ca475 2031 ---help---
e279b6c1
SR
2032 This driver provides a clocksource built upon the on-chip
2033 27MHz high-resolution timer. Its also a workaround for
2034 NSC Geode SC-1100's buggy TSC, which loses time when the
2035 processor goes idle (as is done by the scheduler). The
2036 other workaround is idle=poll boot option.
2037
3ef0e1f8
AS
2038config OLPC
2039 bool "One Laptop Per Child support"
3c554946 2040 select GPIOLIB
8f9ca475 2041 ---help---
3ef0e1f8
AS
2042 Add support for detecting the unique features of the OLPC
2043 XO hardware.
2044
bc0120fd
SR
2045endif # X86_32
2046
e279b6c1
SR
2047config K8_NB
2048 def_bool y
0e152cd7 2049 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2050
2051source "drivers/pcmcia/Kconfig"
2052
2053source "drivers/pci/hotplug/Kconfig"
2054
2055endmenu
2056
2057
2058menu "Executable file formats / Emulations"
2059
2060source "fs/Kconfig.binfmt"
2061
2062config IA32_EMULATION
2063 bool "IA32 Emulation"
2064 depends on X86_64
a97f52e6 2065 select COMPAT_BINFMT_ELF
8f9ca475 2066 ---help---
e279b6c1
SR
2067 Include code to run 32-bit programs under a 64-bit kernel. You should
2068 likely turn this on, unless you're 100% sure that you don't have any
2069 32-bit programs left.
2070
2071config IA32_AOUT
8f9ca475
IM
2072 tristate "IA32 a.out support"
2073 depends on IA32_EMULATION
2074 ---help---
2075 Support old a.out binaries in the 32bit emulation.
e279b6c1
SR
2076
2077config COMPAT
3c2362e6 2078 def_bool y
e279b6c1 2079 depends on IA32_EMULATION
e279b6c1
SR
2080
2081config COMPAT_FOR_U64_ALIGNMENT
2082 def_bool COMPAT
2083 depends on X86_64
2084
2085config SYSVIPC_COMPAT
3c2362e6 2086 def_bool y
b8992195 2087 depends on COMPAT && SYSVIPC
e279b6c1
SR
2088
2089endmenu
2090
2091
e5beae16
KP
2092config HAVE_ATOMIC_IOMAP
2093 def_bool y
2094 depends on X86_32
2095
e279b6c1
SR
2096source "net/Kconfig"
2097
2098source "drivers/Kconfig"
2099
2100source "drivers/firmware/Kconfig"
2101
2102source "fs/Kconfig"
2103
e279b6c1
SR
2104source "arch/x86/Kconfig.debug"
2105
2106source "security/Kconfig"
2107
2108source "crypto/Kconfig"
2109
edf88417
AK
2110source "arch/x86/kvm/Kconfig"
2111
e279b6c1 2112source "lib/Kconfig"