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x86, mce: add MSR read wrappers for easier error injection
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1032c0ba 1# x86 configuration
daa93fab
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2mainmenu "Linux Kernel Configuration for x86"
3
4# Select 32 or 64 bit
5config 64BIT
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6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
8f9ca475 8 ---help---
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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
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17
18### Arch settings
8d5fffb9 19config X86
3c2362e6 20 def_bool y
e17c6d56 21 select HAVE_AOUT if X86_32
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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
28b2ee20 27 select HAVE_IOREMAP_PROT
3f550096 28 select HAVE_KPROBES
1f972768 29 select ARCH_WANT_OPTIONAL_GPIOLIB
da4276b8 30 select ARCH_WANT_FRAME_POINTERS
9edddaa2 31 select HAVE_KRETPROBES
e4b2b886 32 select HAVE_FTRACE_MCOUNT_RECORD
677aa9f7 33 select HAVE_DYNAMIC_FTRACE
606576ce 34 select HAVE_FUNCTION_TRACER
48d68b20 35 select HAVE_FUNCTION_GRAPH_TRACER
60a7ecf4 36 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
9a5fd902 37 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
1b3fa2ce 38 select HAVE_FTRACE_SYSCALLS
e0ec9483 39 select HAVE_KVM
49793b03 40 select HAVE_ARCH_KGDB
99bbc4b1 41 select HAVE_ARCH_TRACEHOOK
323ec001 42 select HAVE_GENERIC_DMA_COHERENT if X86_32
58340a07 43 select HAVE_EFFICIENT_UNALIGNED_ACCESS
8d26487f 44 select USER_STACKTRACE_SUPPORT
2118d0c5 45 select HAVE_DMA_API_DEBUG
2e9f3bdd
PA
46 select HAVE_KERNEL_GZIP
47 select HAVE_KERNEL_BZIP2
48 select HAVE_KERNEL_LZMA
7d8330a5 49
73531905 50config ARCH_DEFCONFIG
b9b39bfb 51 string
73531905
SR
52 default "arch/x86/configs/i386_defconfig" if X86_32
53 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 54
8d5fffb9 55config GENERIC_TIME
3c2362e6 56 def_bool y
8d5fffb9
SR
57
58config GENERIC_CMOS_UPDATE
3c2362e6 59 def_bool y
8d5fffb9
SR
60
61config CLOCKSOURCE_WATCHDOG
3c2362e6 62 def_bool y
8d5fffb9
SR
63
64config GENERIC_CLOCKEVENTS
3c2362e6 65 def_bool y
8d5fffb9
SR
66
67config GENERIC_CLOCKEVENTS_BROADCAST
3c2362e6 68 def_bool y
8d5fffb9
SR
69 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
70
71config LOCKDEP_SUPPORT
3c2362e6 72 def_bool y
8d5fffb9
SR
73
74config STACKTRACE_SUPPORT
3c2362e6 75 def_bool y
8d5fffb9 76
aa7d9350
HC
77config HAVE_LATENCYTOP_SUPPORT
78 def_bool y
79
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CL
80config FAST_CMPXCHG_LOCAL
81 bool
82 default y
83
8d5fffb9 84config MMU
3c2362e6 85 def_bool y
8d5fffb9
SR
86
87config ZONE_DMA
3c2362e6 88 def_bool y
8d5fffb9 89
8d5fffb9
SR
90config SBUS
91 bool
92
93config GENERIC_ISA_DMA
3c2362e6 94 def_bool y
8d5fffb9
SR
95
96config GENERIC_IOMAP
3c2362e6 97 def_bool y
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SR
98
99config GENERIC_BUG
3c2362e6 100 def_bool y
8d5fffb9 101 depends on BUG
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JB
102 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
103
104config GENERIC_BUG_RELATIVE_POINTERS
105 bool
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106
107config GENERIC_HWEIGHT
3c2362e6 108 def_bool y
8d5fffb9 109
a6082959 110config GENERIC_GPIO
9ba16087 111 bool
a6082959 112
8d5fffb9 113config ARCH_MAY_HAVE_PC_FDC
3c2362e6 114 def_bool y
8d5fffb9 115
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116config RWSEM_GENERIC_SPINLOCK
117 def_bool !X86_XADD
118
119config RWSEM_XCHGADD_ALGORITHM
120 def_bool X86_XADD
121
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VP
122config ARCH_HAS_CPU_IDLE_WAIT
123 def_bool y
124
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SR
125config GENERIC_CALIBRATE_DELAY
126 def_bool y
127
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SR
128config GENERIC_TIME_VSYSCALL
129 bool
130 default X86_64
131
9a0b8415 132config ARCH_HAS_CPU_RELAX
133 def_bool y
134
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VP
135config ARCH_HAS_DEFAULT_IDLE
136 def_bool y
137
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PE
138config ARCH_HAS_CACHE_LINE_SIZE
139 def_bool y
140
dd5af90a 141config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 142 def_bool y
b32ef636 143
11124411
TH
144config HAVE_DYNAMIC_PER_CPU_AREA
145 def_bool y
146
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147config HAVE_CPUMASK_OF_CPU_MAP
148 def_bool X86_64_SMP
149
801e4062
JB
150config ARCH_HIBERNATION_POSSIBLE
151 def_bool y
801e4062 152
f4cb5700
JB
153config ARCH_SUSPEND_POSSIBLE
154 def_bool y
f4cb5700 155
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SR
156config ZONE_DMA32
157 bool
158 default X86_64
159
160config ARCH_POPULATES_NODE_MAP
161 def_bool y
162
163config AUDIT_ARCH
164 bool
165 default X86_64
166
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167config ARCH_SUPPORTS_OPTIMIZED_INLINING
168 def_bool y
169
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170config ARCH_SUPPORTS_DEBUG_PAGEALLOC
171 def_bool y
172
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173# Use the generic interrupt handling code in kernel/irq/:
174config GENERIC_HARDIRQS
175 bool
176 default y
177
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178config GENERIC_HARDIRQS_NO__DO_IRQ
179 def_bool y
180
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181config GENERIC_IRQ_PROBE
182 bool
183 default y
184
185config GENERIC_PENDING_IRQ
186 bool
187 depends on GENERIC_HARDIRQS && SMP
188 default y
189
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JB
190config USE_GENERIC_SMP_HELPERS
191 def_bool y
192 depends on SMP
193
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SR
194config X86_32_SMP
195 def_bool y
196 depends on X86_32 && SMP
197
198config X86_64_SMP
199 def_bool y
200 depends on X86_64 && SMP
201
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SR
202config X86_HT
203 bool
ee0011a7 204 depends on SMP
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205 default y
206
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207config X86_TRAMPOLINE
208 bool
3e5095d1 209 depends on SMP || (64BIT && ACPI_SLEEP)
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210 default y
211
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212config X86_32_LAZY_GS
213 def_bool y
60a5317f 214 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 215
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216config KTIME_SCALAR
217 def_bool X86_32
506f1d07 218source "init/Kconfig"
dc52ddc0 219source "kernel/Kconfig.freezer"
8d5fffb9 220
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SR
221menu "Processor type and features"
222
223source "kernel/time/Kconfig"
224
225config SMP
226 bool "Symmetric multi-processing support"
227 ---help---
228 This enables support for systems with more than one CPU. If you have
229 a system with only one CPU, like most personal computers, say N. If
230 you have a system with more than one CPU, say Y.
231
232 If you say N here, the kernel will run on single and multiprocessor
233 machines, but will use only one CPU of a multiprocessor machine. If
234 you say Y here, the kernel will run on many, but not all,
235 singleprocessor machines. On a singleprocessor machine, the kernel
236 will run faster if you say N here.
237
238 Note that if you say Y here and choose architecture "586" or
239 "Pentium" under "Processor family", the kernel will not work on 486
240 architectures. Similarly, multiprocessor kernels for the "PPro"
241 architecture may not work on all Pentium based boards.
242
243 People using multiprocessor machines who say Y here should also say
244 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
245 Management" code will be disabled if you say Y here.
246
03502faa 247 See also <file:Documentation/i386/IO-APIC.txt>,
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248 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
249 <http://www.tldp.org/docs.html#howto>.
250
251 If you don't know what to do here, say N.
252
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253config X86_X2APIC
254 bool "Support x2apic"
f7d7f866 255 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
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256 ---help---
257 This enables x2apic support on CPUs that have this feature.
258
259 This allows 32-bit apic IDs (so it can support very large systems),
260 and accesses the local apic via MSRs not via mmio.
261
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262 If you don't know what to do here, say N.
263
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264config SPARSE_IRQ
265 bool "Support sparse irq numbering"
17483a1f 266 depends on PCI_MSI || HT_IRQ
8f9ca475 267 ---help---
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268 This enables support for sparse irqs. This is useful for distro
269 kernels that want to define a high CONFIG_NR_CPUS value but still
270 want to have low kernel memory footprint on smaller machines.
0b8f1efa 271
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IM
272 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
273 out the irq_desc[] array in a more NUMA-friendly way. )
274
275 If you don't know what to do here, say N.
0b8f1efa 276
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277config NUMA_MIGRATE_IRQ_DESC
278 bool "Move irq desc when changing irq smp_affinity"
b9098957 279 depends on SPARSE_IRQ && NUMA
ca713c2a 280 depends on BROKEN
48a1b10a 281 default n
8f9ca475 282 ---help---
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YL
283 This enables moving irq_desc to cpu/node that irq will use handled.
284
285 If you don't know what to do here, say N.
286
6695c85b 287config X86_MPPARSE
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JB
288 bool "Enable MPS table" if ACPI
289 default y
5ab74722 290 depends on X86_LOCAL_APIC
8f9ca475 291 ---help---
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292 For old smp systems that do not have proper acpi support. Newer systems
293 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 294
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295config X86_BIGSMP
296 bool "Support for big SMP systems with more than 8 CPUs"
297 depends on X86_32 && SMP
8f9ca475 298 ---help---
26f7ef14
YL
299 This option is needed for the systems that have more than 8 CPUs
300
8425091f 301if X86_32
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RT
302config X86_EXTENDED_PLATFORM
303 bool "Support for extended (non-PC) x86 platforms"
304 default y
8f9ca475 305 ---help---
06ac8346
IM
306 If you disable this option then the kernel will only support
307 standard PC platforms. (which covers the vast majority of
308 systems out there.)
309
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RT
310 If you enable this option then you'll be able to select support
311 for the following (non-PC) 32 bit x86 platforms:
312 AMD Elan
313 NUMAQ (IBM/Sequent)
314 RDC R-321x SoC
315 SGI 320/540 (Visual Workstation)
316 Summit/EXA (IBM x440)
317 Unisys ES7000 IA32 series
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IM
318
319 If you have one of these systems, or if you want to build a
320 generic distribution kernel, say Y here - otherwise say N.
8425091f 321endif
06ac8346 322
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RT
323if X86_64
324config X86_EXTENDED_PLATFORM
325 bool "Support for extended (non-PC) x86 platforms"
326 default y
327 ---help---
328 If you disable this option then the kernel will only support
329 standard PC platforms. (which covers the vast majority of
330 systems out there.)
331
332 If you enable this option then you'll be able to select support
333 for the following (non-PC) 64 bit x86 platforms:
334 ScaleMP vSMP
335 SGI Ultraviolet
336
337 If you have one of these systems, or if you want to build a
338 generic distribution kernel, say Y here - otherwise say N.
339endif
c5c606d9
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340# This is an alphabetically sorted list of 64 bit extended platforms
341# Please maintain the alphabetic order if and when there are additions
506f1d07 342
c5c606d9
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343config X86_VSMP
344 bool "ScaleMP vSMP"
345 select PARAVIRT
346 depends on X86_64 && PCI
347 depends on X86_EXTENDED_PLATFORM
8f9ca475 348 ---help---
c5c606d9
RT
349 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
350 supposed to run on these EM64T-based machines. Only choose this option
351 if you have one of these machines.
5e3a77e9 352
03b48632
NP
353config X86_UV
354 bool "SGI Ultraviolet"
355 depends on X86_64
c5c606d9 356 depends on X86_EXTENDED_PLATFORM
54c28d29 357 depends on NUMA
7d01d32d 358 select X86_X2APIC
8f9ca475 359 ---help---
03b48632
NP
360 This option is needed in order to support SGI Ultraviolet systems.
361 If you don't have one of these, you should say N here.
362
c5c606d9
RT
363# Following is an alphabetically sorted list of 32 bit extended platforms
364# Please maintain the alphabetic order if and when there are additions
6a48565e 365
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IM
366config X86_ELAN
367 bool "AMD Elan"
368 depends on X86_32
c5c606d9 369 depends on X86_EXTENDED_PLATFORM
8f9ca475 370 ---help---
9e111f3e
IM
371 Select this for an AMD Elan processor.
372
373 Do not use this option for K6/Athlon/Opteron processors!
374
375 If unsure, choose "PC-compatible" instead.
376
c5c606d9
RT
377config X86_RDC321X
378 bool "RDC R-321x SoC"
379 depends on X86_32
380 depends on X86_EXTENDED_PLATFORM
381 select M486
382 select X86_REBOOTFIXUPS
383 ---help---
384 This option is needed for RDC R-321x system-on-chip, also known
385 as R-8610-(G).
386 If you don't have one of these chips, you should say N here.
387
e0c7ae37 388config X86_32_NON_STANDARD
9c398017
IM
389 bool "Support non-standard 32-bit SMP architectures"
390 depends on X86_32 && SMP
c5c606d9 391 depends on X86_EXTENDED_PLATFORM
8f9ca475
IM
392 ---help---
393 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
9c398017
IM
394 subarchitectures. It is intended for a generic binary kernel.
395 if you select them all, kernel will probe it one by one. and will
396 fallback to default.
397
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RT
398# Alphabetically sorted list of Non standard 32 bit platforms
399
9c398017
IM
400config X86_NUMAQ
401 bool "NUMAQ (IBM/Sequent)"
e0c7ae37 402 depends on X86_32_NON_STANDARD
9c398017
IM
403 select NUMA
404 select X86_MPPARSE
8f9ca475 405 ---help---
9c398017
IM
406 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
407 NUMA multiquad box. This changes the way that processors are
408 bootstrapped, and uses Clustered Logical APIC addressing mode instead
409 of Flat Logical. You will need a new lynxer.elf file to flash your
410 firmware with - send email to <Martin.Bligh@us.ibm.com>.
411
c5c606d9
RT
412config X86_VISWS
413 bool "SGI 320/540 (Visual Workstation)"
414 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
415 depends on X86_32_NON_STANDARD
416 ---help---
417 The SGI Visual Workstation series is an IA32-based workstation
418 based on SGI systems chips with some legacy PC hardware attached.
419
420 Say Y here to create a kernel to run on the SGI 320 or 540.
421
422 A kernel compiled for the Visual Workstation will run on general
423 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
424
9c398017
IM
425config X86_SUMMIT
426 bool "Summit/EXA (IBM x440)"
e0c7ae37 427 depends on X86_32_NON_STANDARD
8f9ca475 428 ---help---
9c398017
IM
429 This option is needed for IBM systems that use the Summit/EXA chipset.
430 In particular, it is needed for the x440.
431
432config X86_ES7000
c5c606d9 433 bool "Unisys ES7000 IA32 series"
26f7ef14 434 depends on X86_32_NON_STANDARD && X86_BIGSMP
8f9ca475 435 ---help---
9c398017
IM
436 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
437 supposed to run on an IA32-based Unisys ES7000 system.
438
ae1e9130 439config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
440 def_bool y
441 prompt "Single-depth WCHAN output"
a87d0914 442 depends on X86
8f9ca475 443 ---help---
506f1d07
SR
444 Calculate simpler /proc/<PID>/wchan values. If this option
445 is disabled then wchan values will recurse back to the
446 caller function. This provides more accurate wchan values,
447 at the expense of slightly more scheduling overhead.
448
449 If in doubt, say "Y".
450
506f1d07
SR
451menuconfig PARAVIRT_GUEST
452 bool "Paravirtualized guest support"
8f9ca475 453 ---help---
506f1d07
SR
454 Say Y here to get to see options related to running Linux under
455 various hypervisors. This option alone does not add any kernel code.
456
457 If you say N, all options in this submenu will be skipped and disabled.
458
459if PARAVIRT_GUEST
460
461source "arch/x86/xen/Kconfig"
462
463config VMI
464 bool "VMI Guest support"
465 select PARAVIRT
42d545c9 466 depends on X86_32
8f9ca475 467 ---help---
506f1d07
SR
468 VMI provides a paravirtualized interface to the VMware ESX server
469 (it could be used by other hypervisors in theory too, but is not
470 at the moment), by linking the kernel to a GPL-ed ROM module
471 provided by the hypervisor.
472
790c73f6
GOC
473config KVM_CLOCK
474 bool "KVM paravirtualized clock"
475 select PARAVIRT
f6e16d5a 476 select PARAVIRT_CLOCK
8f9ca475 477 ---help---
790c73f6
GOC
478 Turning on this option will allow you to run a paravirtualized clock
479 when running over the KVM hypervisor. Instead of relying on a PIT
480 (or probably other) emulation by the underlying device model, the host
481 provides the guest with timing infrastructure such as time of day, and
482 system time
483
0cf1bfd2
MT
484config KVM_GUEST
485 bool "KVM Guest support"
486 select PARAVIRT
8f9ca475
IM
487 ---help---
488 This option enables various optimizations for running under the KVM
489 hypervisor.
0cf1bfd2 490
506f1d07
SR
491source "arch/x86/lguest/Kconfig"
492
e61bd94a
EPH
493config PARAVIRT
494 bool "Enable paravirtualization code"
8f9ca475 495 ---help---
e61bd94a
EPH
496 This changes the kernel so it can modify itself when it is run
497 under a hypervisor, potentially improving performance significantly
498 over full virtualization. However, when run without a hypervisor
499 the kernel is theoretically slower and slightly larger.
500
b4ecc126
JF
501config PARAVIRT_SPINLOCKS
502 bool "Paravirtualization layer for spinlocks"
503 depends on PARAVIRT && SMP && EXPERIMENTAL
504 ---help---
505 Paravirtualized spinlocks allow a pvops backend to replace the
506 spinlock implementation with something virtualization-friendly
507 (for example, block the virtual CPU rather than spinning).
508
509 Unfortunately the downside is an up to 5% performance hit on
510 native kernels, with various workloads.
511
512 If you are unsure how to answer this question, answer N.
513
7af192c9
GH
514config PARAVIRT_CLOCK
515 bool
516 default n
517
506f1d07
SR
518endif
519
97349135 520config PARAVIRT_DEBUG
8f9ca475
IM
521 bool "paravirt-ops debugging"
522 depends on PARAVIRT && DEBUG_KERNEL
523 ---help---
524 Enable to debug paravirt_ops internals. Specifically, BUG if
525 a paravirt_op is missing when it is called.
c64df707 526
03273184
YL
527config MEMTEST
528 bool "Memtest"
8f9ca475 529 ---help---
c64df707 530 This option adds a kernel parameter 'memtest', which allows memtest
03273184 531 to be set.
8f9ca475
IM
532 memtest=0, mean disabled; -- default
533 memtest=1, mean do 1 test pattern;
534 ...
535 memtest=4, mean do 4 test patterns.
aba3728c 536 If you are unsure how to answer this question, answer N.
506f1d07
SR
537
538config X86_SUMMIT_NUMA
3c2362e6 539 def_bool y
e0c7ae37 540 depends on X86_32 && NUMA && X86_32_NON_STANDARD
506f1d07
SR
541
542config X86_CYCLONE_TIMER
3c2362e6 543 def_bool y
e0c7ae37 544 depends on X86_32_NON_STANDARD
506f1d07 545
506f1d07
SR
546source "arch/x86/Kconfig.cpu"
547
548config HPET_TIMER
3c2362e6 549 def_bool X86_64
506f1d07 550 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
551 ---help---
552 Use the IA-PC HPET (High Precision Event Timer) to manage
553 time in preference to the PIT and RTC, if a HPET is
554 present.
555 HPET is the next generation timer replacing legacy 8254s.
556 The HPET provides a stable time base on SMP
557 systems, unlike the TSC, but it is more expensive to access,
558 as it is off-chip. You can find the HPET spec at
559 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
506f1d07 560
8f9ca475
IM
561 You can safely choose Y here. However, HPET will only be
562 activated if the platform and the BIOS support this feature.
563 Otherwise the 8254 will be used for timing services.
506f1d07 564
8f9ca475 565 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
566
567config HPET_EMULATE_RTC
3c2362e6 568 def_bool y
9d8af78b 569 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07
SR
570
571# Mark as embedded because too many people got it wrong.
572# The code disables itself when not needed.
7ae9392c
TP
573config DMI
574 default y
575 bool "Enable DMI scanning" if EMBEDDED
8f9ca475 576 ---help---
7ae9392c
TP
577 Enabled scanning of DMI to identify machine quirks. Say Y
578 here unless you have verified that your setup is not
579 affected by entries in the DMI blacklist. Required by PNP
580 BIOS code.
581
506f1d07
SR
582config GART_IOMMU
583 bool "GART IOMMU support" if EMBEDDED
584 default y
585 select SWIOTLB
586 select AGP
587 depends on X86_64 && PCI
8f9ca475 588 ---help---
506f1d07
SR
589 Support for full DMA access of devices with 32bit memory access only
590 on systems with more than 3GB. This is usually needed for USB,
591 sound, many IDE/SATA chipsets and some other devices.
592 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
593 based hardware IOMMU and a software bounce buffer based IOMMU used
594 on Intel systems and as fallback.
595 The code is only active when needed (enough memory and limited
596 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
597 too.
598
599config CALGARY_IOMMU
600 bool "IBM Calgary IOMMU support"
601 select SWIOTLB
602 depends on X86_64 && PCI && EXPERIMENTAL
8f9ca475 603 ---help---
506f1d07
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604 Support for hardware IOMMUs in IBM's xSeries x366 and x460
605 systems. Needed to run systems with more than 3GB of memory
606 properly with 32-bit PCI devices that do not support DAC
607 (Double Address Cycle). Calgary also supports bus level
608 isolation, where all DMAs pass through the IOMMU. This
609 prevents them from going anywhere except their intended
610 destination. This catches hard-to-find kernel bugs and
611 mis-behaving drivers and devices that do not use the DMA-API
612 properly to set up their DMA buffers. The IOMMU can be
613 turned off at boot time with the iommu=off parameter.
614 Normally the kernel will make the right choice by itself.
615 If unsure, say Y.
616
617config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
618 def_bool y
619 prompt "Should Calgary be enabled by default?"
506f1d07 620 depends on CALGARY_IOMMU
8f9ca475 621 ---help---
506f1d07
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622 Should Calgary be enabled by default? if you choose 'y', Calgary
623 will be used (if it exists). If you choose 'n', Calgary will not be
624 used even if it exists. If you choose 'n' and would like to use
625 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
626 If unsure, say Y.
627
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628config AMD_IOMMU
629 bool "AMD IOMMU support"
07c40e8a 630 select SWIOTLB
a80dc3e0 631 select PCI_MSI
24d2ba0a 632 depends on X86_64 && PCI && ACPI
8f9ca475 633 ---help---
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634 With this option you can enable support for AMD IOMMU hardware in
635 your system. An IOMMU is a hardware component which provides
636 remapping of DMA memory accesses from devices. With an AMD IOMMU you
637 can isolate the the DMA memory of different devices and protect the
638 system from misbehaving device drivers or hardware.
639
640 You can find out if your system has an AMD IOMMU if you look into
641 your BIOS for an option to enable it or if you have an IVRS ACPI
642 table.
2b188723 643
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644config AMD_IOMMU_STATS
645 bool "Export AMD IOMMU statistics to debugfs"
646 depends on AMD_IOMMU
647 select DEBUG_FS
8f9ca475 648 ---help---
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649 This option enables code in the AMD IOMMU driver to collect various
650 statistics about whats happening in the driver and exports that
651 information to userspace via debugfs.
652 If unsure, say N.
653
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SR
654# need this always selected by IOMMU for the VIA workaround
655config SWIOTLB
a1afd01c 656 def_bool y if X86_64
8f9ca475 657 ---help---
506f1d07
SR
658 Support for software bounce buffers used on x86-64 systems
659 which don't have a hardware IOMMU (e.g. the current generation
660 of Intel's x86-64 CPUs). Using this PCI devices which can only
661 access 32-bits of memory can be used on systems with more than
662 3 GB of memory. If unsure, say Y.
663
a8522509 664config IOMMU_HELPER
18b743dc 665 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
d25e26b6 666
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667config IOMMU_API
668 def_bool (AMD_IOMMU || DMAR)
669
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670config MAXSMP
671 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
36f5101a
MT
672 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
673 select CPUMASK_OFFSTACK
1184dc2f 674 default n
8f9ca475 675 ---help---
1184dc2f
MT
676 Configure maximum number of CPUS and NUMA Nodes for this architecture.
677 If unsure, say N.
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678
679config NR_CPUS
36f5101a 680 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 681 range 2 8 if SMP && X86_32 && !X86_BIGSMP
36f5101a 682 range 2 512 if SMP && !MAXSMP
78637a97 683 default "1" if !SMP
d25e26b6 684 default "4096" if MAXSMP
78637a97
MT
685 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
686 default "8" if SMP
8f9ca475 687 ---help---
506f1d07 688 This allows you to specify the maximum number of CPUs which this
d25e26b6 689 kernel will support. The maximum supported value is 512 and the
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SR
690 minimum value which makes sense is 2.
691
692 This is purely to save memory - each supported CPU adds
693 approximately eight kilobytes to the kernel image.
694
695config SCHED_SMT
696 bool "SMT (Hyperthreading) scheduler support"
b089c12b 697 depends on X86_HT
8f9ca475 698 ---help---
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SR
699 SMT scheduler support improves the CPU scheduler's decision making
700 when dealing with Intel Pentium 4 chips with HyperThreading at a
701 cost of slightly increased overhead in some places. If unsure say
702 N here.
703
704config SCHED_MC
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HH
705 def_bool y
706 prompt "Multi-core scheduler support"
b089c12b 707 depends on X86_HT
8f9ca475 708 ---help---
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SR
709 Multi-core scheduler support improves the CPU scheduler's decision
710 making when dealing with multi-core CPU chips at a cost of slightly
711 increased overhead in some places. If unsure say N here.
712
713source "kernel/Kconfig.preempt"
714
715config X86_UP_APIC
716 bool "Local APIC support on uniprocessors"
e0c7ae37 717 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 718 ---help---
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SR
719 A local APIC (Advanced Programmable Interrupt Controller) is an
720 integrated interrupt controller in the CPU. If you have a single-CPU
721 system which has a processor with a local APIC, you can say Y here to
722 enable and use it. If you say Y here even though your machine doesn't
723 have a local APIC, then the kernel will still run with no slowdown at
724 all. The local APIC supports CPU-generated self-interrupts (timer,
725 performance counters), and the NMI watchdog which detects hard
726 lockups.
727
728config X86_UP_IOAPIC
729 bool "IO-APIC support on uniprocessors"
730 depends on X86_UP_APIC
8f9ca475 731 ---help---
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SR
732 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
733 SMP-capable replacement for PC-style interrupt controllers. Most
734 SMP systems and many recent uniprocessor systems have one.
735
736 If you have a single-CPU system with an IO-APIC, you can say Y here
737 to use it. If you say Y here even though your machine doesn't have
738 an IO-APIC, then the kernel will still run with no slowdown at all.
739
740config X86_LOCAL_APIC
3c2362e6 741 def_bool y
e0c7ae37 742 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
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SR
743
744config X86_IO_APIC
3c2362e6 745 def_bool y
e0c7ae37 746 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
747
748config X86_VISWS_APIC
3c2362e6 749 def_bool y
506f1d07 750 depends on X86_32 && X86_VISWS
506f1d07 751
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SA
752config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
753 bool "Reroute for broken boot IRQs"
754 default n
755 depends on X86_IO_APIC
8f9ca475 756 ---help---
41b9eb26
SA
757 This option enables a workaround that fixes a source of
758 spurious interrupts. This is recommended when threaded
759 interrupt handling is used on systems where the generation of
760 superfluous "boot interrupts" cannot be disabled.
761
762 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
763 entry in the chipset's IO-APIC is masked (as, e.g. the RT
764 kernel does during interrupt handling). On chipsets where this
765 boot IRQ generation cannot be disabled, this workaround keeps
766 the original IRQ line masked so that only the equivalent "boot
767 IRQ" is delivered to the CPUs. The workaround also tells the
768 kernel to set up the IRQ handler on the boot IRQ line. In this
769 way only one interrupt is delivered to the kernel. Otherwise
770 the spurious second interrupt may cause the kernel to bring
771 down (vital) interrupt lines.
772
773 Only affects "broken" chipsets. Interrupt sharing may be
774 increased on these systems.
775
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SR
776config X86_MCE
777 bool "Machine Check Exception"
506f1d07
SR
778 ---help---
779 Machine Check Exception support allows the processor to notify the
780 kernel if it detects a problem (e.g. overheating, component failure).
781 The action the kernel takes depends on the severity of the problem,
782 ranging from a warning message on the console, to halting the machine.
783 Your processor must be a Pentium or newer to support this - check the
784 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
785 have a design flaw which leads to false MCE events - hence MCE is
786 disabled on all P5 processors, unless explicitly enabled with "mce"
787 as a boot argument. Similarly, if MCE is built in and creates a
788 problem on some new non-standard machine, you can boot with "nomce"
789 to disable it. MCE support simply ignores non-MCE processors like
790 the 386 and 486, so nearly everyone can say Y here.
791
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792config X86_OLD_MCE
793 depends on X86_32 && X86_MCE
794 bool "Use legacy machine check code (will go away)"
795 default n
796 select X86_ANCIENT_MCE
797 ---help---
798 Use the old i386 machine check code. This is merely intended for
799 testing in a transition period. Try this if you run into any machine
800 check related software problems, but report the problem to
801 linux-kernel. When in doubt say no.
802
803config X86_NEW_MCE
804 depends on X86_MCE
805 bool
806 default y if (!X86_OLD_MCE && X86_32) || X86_64
807
506f1d07 808config X86_MCE_INTEL
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HH
809 def_bool y
810 prompt "Intel MCE features"
7856f6cc 811 depends on X86_NEW_MCE && X86_LOCAL_APIC
8f9ca475 812 ---help---
506f1d07
SR
813 Additional support for intel specific MCE features such as
814 the thermal monitor.
815
816config X86_MCE_AMD
3c2362e6
HH
817 def_bool y
818 prompt "AMD MCE features"
de5619df 819 depends on X86_NEW_MCE && X86_LOCAL_APIC
8f9ca475 820 ---help---
506f1d07
SR
821 Additional support for AMD specific MCE features such as
822 the DRAM Error Threshold.
823
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824config X86_ANCIENT_MCE
825 def_bool n
826 depends on X86_32
827 prompt "Support for old Pentium 5 / WinChip machine checks"
828 ---help---
829 Include support for machine check handling on old Pentium 5 or WinChip
830 systems. These typically need to be enabled explicitely on the command
831 line.
832
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AK
833config X86_MCE_THRESHOLD
834 depends on X86_MCE_AMD || X86_MCE_INTEL
835 bool
836 default y
837
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SR
838config X86_MCE_NONFATAL
839 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
4efc0670 840 depends on X86_OLD_MCE
8f9ca475 841 ---help---
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SR
842 Enabling this feature starts a timer that triggers every 5 seconds which
843 will look at the machine check registers to see if anything happened.
844 Non-fatal problems automatically get corrected (but still logged).
845 Disable this if you don't want to see these messages.
846 Seeing the messages this option prints out may be indicative of dying
847 or out-of-spec (ie, overclocked) hardware.
848 This option only does something on certain CPUs.
849 (AMD Athlon/Duron and Intel Pentium 4)
850
851config X86_MCE_P4THERMAL
852 bool "check for P4 thermal throttling interrupt."
4efc0670 853 depends on X86_OLD_MCE && X86_MCE && (X86_UP_APIC || SMP)
8f9ca475 854 ---help---
506f1d07
SR
855 Enabling this feature will cause a message to be printed when the P4
856 enters thermal throttling.
857
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AK
858config X86_THERMAL_VECTOR
859 def_bool y
860 depends on X86_MCE_P4THERMAL || X86_MCE_INTEL
861
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SR
862config VM86
863 bool "Enable VM86 support" if EMBEDDED
864 default y
865 depends on X86_32
8f9ca475
IM
866 ---help---
867 This option is required by programs like DOSEMU to run 16-bit legacy
506f1d07 868 code on X86 processors. It also may be needed by software like
8f9ca475
IM
869 XFree86 to initialize some video cards via BIOS. Disabling this
870 option saves about 6k.
506f1d07
SR
871
872config TOSHIBA
873 tristate "Toshiba Laptop support"
874 depends on X86_32
875 ---help---
876 This adds a driver to safely access the System Management Mode of
877 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
878 not work on models with a Phoenix BIOS. The System Management Mode
879 is used to set the BIOS and power saving options on Toshiba portables.
880
881 For information on utilities to make use of this driver see the
882 Toshiba Linux utilities web site at:
883 <http://www.buzzard.org.uk/toshiba/>.
884
885 Say Y if you intend to run this kernel on a Toshiba portable.
886 Say N otherwise.
887
888config I8K
889 tristate "Dell laptop support"
506f1d07
SR
890 ---help---
891 This adds a driver to safely access the System Management Mode
892 of the CPU on the Dell Inspiron 8000. The System Management Mode
893 is used to read cpu temperature and cooling fan status and to
894 control the fans on the I8K portables.
895
896 This driver has been tested only on the Inspiron 8000 but it may
897 also work with other Dell laptops. You can force loading on other
898 models by passing the parameter `force=1' to the module. Use at
899 your own risk.
900
901 For information on utilities to make use of this driver see the
902 I8K Linux utilities web site at:
903 <http://people.debian.org/~dz/i8k/>
904
905 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
906 Say N otherwise.
907
908config X86_REBOOTFIXUPS
9ba16087
JB
909 bool "Enable X86 board specific fixups for reboot"
910 depends on X86_32
506f1d07
SR
911 ---help---
912 This enables chipset and/or board specific fixups to be done
913 in order to get reboot to work correctly. This is only needed on
914 some combinations of hardware and BIOS. The symptom, for which
915 this config is intended, is when reboot ends with a stalled/hung
916 system.
917
918 Currently, the only fixup is for the Geode machines using
5e3a77e9 919 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
920
921 Say Y if you want to enable the fixup. Currently, it's safe to
922 enable this option even if you don't need it.
923 Say N otherwise.
924
925config MICROCODE
8d86f390 926 tristate "/dev/cpu/microcode - microcode support"
506f1d07
SR
927 select FW_LOADER
928 ---help---
929 If you say Y here, you will be able to update the microcode on
80cc9f10
PO
930 certain Intel and AMD processors. The Intel support is for the
931 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
932 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
933 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
934 You will obviously need the actual microcode binary data itself
935 which is not shipped with the Linux kernel.
506f1d07 936
8d86f390
PO
937 This option selects the general module only, you need to select
938 at least one vendor specific module as well.
506f1d07
SR
939
940 To compile this driver as a module, choose M here: the
941 module will be called microcode.
942
8d86f390 943config MICROCODE_INTEL
8f9ca475
IM
944 bool "Intel microcode patch loading support"
945 depends on MICROCODE
946 default MICROCODE
947 select FW_LOADER
948 ---help---
949 This options enables microcode patch loading support for Intel
950 processors.
951
952 For latest news and information on obtaining all the required
953 Intel ingredients for this driver, check:
954 <http://www.urbanmyth.org/microcode/>.
8d86f390 955
80cc9f10 956config MICROCODE_AMD
8f9ca475
IM
957 bool "AMD microcode patch loading support"
958 depends on MICROCODE
959 select FW_LOADER
960 ---help---
961 If you select this option, microcode patch loading support for AMD
962 processors will be enabled.
80cc9f10 963
8f9ca475 964config MICROCODE_OLD_INTERFACE
3c2362e6 965 def_bool y
506f1d07 966 depends on MICROCODE
506f1d07
SR
967
968config X86_MSR
969 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 970 ---help---
506f1d07
SR
971 This device gives privileged processes access to the x86
972 Model-Specific Registers (MSRs). It is a character device with
973 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
974 MSR accesses are directed to a specific CPU on multi-processor
975 systems.
976
977config X86_CPUID
978 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 979 ---help---
506f1d07
SR
980 This device gives processes access to the x86 CPUID instruction to
981 be executed on a specific processor. It is a character device
982 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
983 /dev/cpu/31/cpuid.
984
9b779edf
JSR
985config X86_CPU_DEBUG
986 tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
987 ---help---
988 If you select this option, this will provide various x86 CPUs
989 information through debugfs.
990
506f1d07
SR
991choice
992 prompt "High Memory Support"
993 default HIGHMEM4G if !X86_NUMAQ
994 default HIGHMEM64G if X86_NUMAQ
995 depends on X86_32
996
997config NOHIGHMEM
998 bool "off"
999 depends on !X86_NUMAQ
1000 ---help---
1001 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1002 However, the address space of 32-bit x86 processors is only 4
1003 Gigabytes large. That means that, if you have a large amount of
1004 physical memory, not all of it can be "permanently mapped" by the
1005 kernel. The physical memory that's not permanently mapped is called
1006 "high memory".
1007
1008 If you are compiling a kernel which will never run on a machine with
1009 more than 1 Gigabyte total physical RAM, answer "off" here (default
1010 choice and suitable for most users). This will result in a "3GB/1GB"
1011 split: 3GB are mapped so that each process sees a 3GB virtual memory
1012 space and the remaining part of the 4GB virtual memory space is used
1013 by the kernel to permanently map as much physical memory as
1014 possible.
1015
1016 If the machine has between 1 and 4 Gigabytes physical RAM, then
1017 answer "4GB" here.
1018
1019 If more than 4 Gigabytes is used then answer "64GB" here. This
1020 selection turns Intel PAE (Physical Address Extension) mode on.
1021 PAE implements 3-level paging on IA32 processors. PAE is fully
1022 supported by Linux, PAE mode is implemented on all recent Intel
1023 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1024 then the kernel will not boot on CPUs that don't support PAE!
1025
1026 The actual amount of total physical memory will either be
1027 auto detected or can be forced by using a kernel command line option
1028 such as "mem=256M". (Try "man bootparam" or see the documentation of
1029 your boot loader (lilo or loadlin) about how to pass options to the
1030 kernel at boot time.)
1031
1032 If unsure, say "off".
1033
1034config HIGHMEM4G
1035 bool "4GB"
1036 depends on !X86_NUMAQ
8f9ca475 1037 ---help---
506f1d07
SR
1038 Select this if you have a 32-bit processor and between 1 and 4
1039 gigabytes of physical RAM.
1040
1041config HIGHMEM64G
1042 bool "64GB"
1043 depends on !M386 && !M486
1044 select X86_PAE
8f9ca475 1045 ---help---
506f1d07
SR
1046 Select this if you have a 32-bit processor and more than 4
1047 gigabytes of physical RAM.
1048
1049endchoice
1050
1051choice
1052 depends on EXPERIMENTAL
1053 prompt "Memory split" if EMBEDDED
1054 default VMSPLIT_3G
1055 depends on X86_32
8f9ca475 1056 ---help---
506f1d07
SR
1057 Select the desired split between kernel and user memory.
1058
1059 If the address range available to the kernel is less than the
1060 physical memory installed, the remaining memory will be available
1061 as "high memory". Accessing high memory is a little more costly
1062 than low memory, as it needs to be mapped into the kernel first.
1063 Note that increasing the kernel address space limits the range
1064 available to user programs, making the address space there
1065 tighter. Selecting anything other than the default 3G/1G split
1066 will also likely make your kernel incompatible with binary-only
1067 kernel modules.
1068
1069 If you are not absolutely sure what you are doing, leave this
1070 option alone!
1071
1072 config VMSPLIT_3G
1073 bool "3G/1G user/kernel split"
1074 config VMSPLIT_3G_OPT
1075 depends on !X86_PAE
1076 bool "3G/1G user/kernel split (for full 1G low memory)"
1077 config VMSPLIT_2G
1078 bool "2G/2G user/kernel split"
1079 config VMSPLIT_2G_OPT
1080 depends on !X86_PAE
1081 bool "2G/2G user/kernel split (for full 2G low memory)"
1082 config VMSPLIT_1G
1083 bool "1G/3G user/kernel split"
1084endchoice
1085
1086config PAGE_OFFSET
1087 hex
1088 default 0xB0000000 if VMSPLIT_3G_OPT
1089 default 0x80000000 if VMSPLIT_2G
1090 default 0x78000000 if VMSPLIT_2G_OPT
1091 default 0x40000000 if VMSPLIT_1G
1092 default 0xC0000000
1093 depends on X86_32
1094
1095config HIGHMEM
3c2362e6 1096 def_bool y
506f1d07 1097 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1098
1099config X86_PAE
9ba16087 1100 bool "PAE (Physical Address Extension) Support"
506f1d07 1101 depends on X86_32 && !HIGHMEM4G
8f9ca475 1102 ---help---
506f1d07
SR
1103 PAE is required for NX support, and furthermore enables
1104 larger swapspace support for non-overcommit purposes. It
1105 has the cost of more pagetable lookup overhead, and also
1106 consumes more pagetable space per process.
1107
600715dc 1108config ARCH_PHYS_ADDR_T_64BIT
8f9ca475 1109 def_bool X86_64 || X86_PAE
600715dc 1110
9e899816
NP
1111config DIRECT_GBPAGES
1112 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1113 default y
1114 depends on X86_64
8f9ca475 1115 ---help---
9e899816
NP
1116 Allow the kernel linear mapping to use 1GB pages on CPUs that
1117 support it. This can improve the kernel's performance a tiny bit by
1118 reducing TLB pressure. If in doubt, say "Y".
1119
506f1d07
SR
1120# Common NUMA Features
1121config NUMA
fd51b2d7 1122 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1123 depends on SMP
0699eae1 1124 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
0699eae1 1125 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
8f9ca475 1126 ---help---
506f1d07 1127 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1128
506f1d07
SR
1129 The kernel will try to allocate memory used by a CPU on the
1130 local memory controller of the CPU and add some more
1131 NUMA awareness to the kernel.
1132
c280ea5e 1133 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1134 (or later), AMD Opteron, or EM64T NUMA.
1135
1136 For 32-bit this is only needed on (rare) 32-bit-only platforms
1137 that support NUMA topologies, such as NUMAQ / Summit, or if you
1138 boot a 32-bit kernel on a 64-bit NUMA platform.
1139
1140 Otherwise, you should say N.
506f1d07
SR
1141
1142comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1143 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1144
1145config K8_NUMA
3c2362e6
HH
1146 def_bool y
1147 prompt "Old style AMD Opteron NUMA detection"
1148 depends on X86_64 && NUMA && PCI
8f9ca475
IM
1149 ---help---
1150 Enable K8 NUMA node topology detection. You should say Y here if
1151 you have a multi processor AMD K8 system. This uses an old
1152 method to read the NUMA configuration directly from the builtin
1153 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1154 instead, which also takes priority if both are compiled in.
506f1d07
SR
1155
1156config X86_64_ACPI_NUMA
3c2362e6
HH
1157 def_bool y
1158 prompt "ACPI NUMA detection"
506f1d07
SR
1159 depends on X86_64 && NUMA && ACPI && PCI
1160 select ACPI_NUMA
8f9ca475 1161 ---help---
506f1d07
SR
1162 Enable ACPI SRAT based node topology detection.
1163
6ec6e0d9
SS
1164# Some NUMA nodes have memory ranges that span
1165# other nodes. Even though a pfn is valid and
1166# between a node's start and end pfns, it may not
1167# reside on that node. See memmap_init_zone()
1168# for details.
1169config NODES_SPAN_OTHER_NODES
1170 def_bool y
1171 depends on X86_64_ACPI_NUMA
1172
506f1d07
SR
1173config NUMA_EMU
1174 bool "NUMA emulation"
1175 depends on X86_64 && NUMA
8f9ca475 1176 ---help---
506f1d07
SR
1177 Enable NUMA emulation. A flat machine will be split
1178 into virtual nodes when booted with "numa=fake=N", where N is the
1179 number of nodes. This is only useful for debugging.
1180
1181config NODES_SHIFT
d25e26b6 1182 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
46d50c98 1183 range 1 9
d25e26b6 1184 default "9" if MAXSMP
506f1d07
SR
1185 default "6" if X86_64
1186 default "4" if X86_NUMAQ
1187 default "3"
1188 depends on NEED_MULTIPLE_NODES
8f9ca475 1189 ---help---
1184dc2f 1190 Specify the maximum number of NUMA Nodes available on the target
692105b8 1191 system. Increases memory reserved to accommodate various tables.
506f1d07 1192
c1329375 1193config HAVE_ARCH_BOOTMEM
3c2362e6 1194 def_bool y
506f1d07 1195 depends on X86_32 && NUMA
506f1d07
SR
1196
1197config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1198 def_bool y
506f1d07 1199 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1200
1201config NEED_NODE_MEMMAP_SIZE
3c2362e6 1202 def_bool y
506f1d07 1203 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07
SR
1204
1205config HAVE_ARCH_ALLOC_REMAP
3c2362e6 1206 def_bool y
506f1d07 1207 depends on X86_32 && NUMA
506f1d07
SR
1208
1209config ARCH_FLATMEM_ENABLE
1210 def_bool y
99809963 1211 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
506f1d07
SR
1212
1213config ARCH_DISCONTIGMEM_ENABLE
1214 def_bool y
b263295d 1215 depends on NUMA && X86_32
506f1d07
SR
1216
1217config ARCH_DISCONTIGMEM_DEFAULT
1218 def_bool y
b263295d
CL
1219 depends on NUMA && X86_32
1220
1221config ARCH_SPARSEMEM_DEFAULT
1222 def_bool y
1223 depends on X86_64
506f1d07
SR
1224
1225config ARCH_SPARSEMEM_ENABLE
1226 def_bool y
4272ebfb 1227 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
506f1d07
SR
1228 select SPARSEMEM_STATIC if X86_32
1229 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1230
1231config ARCH_SELECT_MEMORY_MODEL
1232 def_bool y
b263295d 1233 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1234
1235config ARCH_MEMORY_PROBE
1236 def_bool X86_64
1237 depends on MEMORY_HOTPLUG
1238
1239source "mm/Kconfig"
1240
1241config HIGHPTE
1242 bool "Allocate 3rd-level pagetables from highmem"
1243 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
8f9ca475 1244 ---help---
506f1d07
SR
1245 The VM uses one page table entry for each page of physical memory.
1246 For systems with a lot of RAM, this can be wasteful of precious
1247 low memory. Setting this option will put user-space page table
1248 entries in high memory.
1249
9f077871 1250config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1251 bool "Check for low memory corruption"
1252 ---help---
1253 Periodically check for memory corruption in low memory, which
1254 is suspected to be caused by BIOS. Even when enabled in the
1255 configuration, it is disabled at runtime. Enable it by
1256 setting "memory_corruption_check=1" on the kernel command
1257 line. By default it scans the low 64k of memory every 60
1258 seconds; see the memory_corruption_check_size and
1259 memory_corruption_check_period parameters in
1260 Documentation/kernel-parameters.txt to adjust this.
1261
1262 When enabled with the default parameters, this option has
1263 almost no overhead, as it reserves a relatively small amount
1264 of memory and scans it infrequently. It both detects corruption
1265 and prevents it from affecting the running system.
1266
1267 It is, however, intended as a diagnostic tool; if repeatable
1268 BIOS-originated corruption always affects the same memory,
1269 you can use memmap= to prevent the kernel from using that
1270 memory.
9f077871 1271
c885df50 1272config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1273 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1274 depends on X86_CHECK_BIOS_CORRUPTION
1275 default y
8f9ca475
IM
1276 ---help---
1277 Set whether the default state of memory_corruption_check is
1278 on or off.
c885df50 1279
fc381519 1280config X86_RESERVE_LOW_64K
8f9ca475 1281 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
fc381519 1282 default y
8f9ca475
IM
1283 ---help---
1284 Reserve the first 64K of physical RAM on BIOSes that are known
1285 to potentially corrupt that memory range. A numbers of BIOSes are
1286 known to utilize this area during suspend/resume, so it must not
1287 be used by the kernel.
fc381519 1288
8f9ca475
IM
1289 Set this to N if you are absolutely sure that you trust the BIOS
1290 to get all its memory reservations and usages right.
fc381519 1291
8f9ca475
IM
1292 If you have doubts about the BIOS (e.g. suspend/resume does not
1293 work or there's kernel crashes after certain hardware hotplug
1294 events) and it's not AMI or Phoenix, then you might want to enable
1295 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1296 corruption patterns.
fc381519 1297
8f9ca475 1298 Say Y if unsure.
fc381519 1299
506f1d07
SR
1300config MATH_EMULATION
1301 bool
1302 prompt "Math emulation" if X86_32
1303 ---help---
1304 Linux can emulate a math coprocessor (used for floating point
1305 operations) if you don't have one. 486DX and Pentium processors have
1306 a math coprocessor built in, 486SX and 386 do not, unless you added
1307 a 487DX or 387, respectively. (The messages during boot time can
1308 give you some hints here ["man dmesg"].) Everyone needs either a
1309 coprocessor or this emulation.
1310
1311 If you don't have a math coprocessor, you need to say Y here; if you
1312 say Y here even though you have a coprocessor, the coprocessor will
1313 be used nevertheless. (This behavior can be changed with the kernel
1314 command line option "no387", which comes handy if your coprocessor
1315 is broken. Try "man bootparam" or see the documentation of your boot
1316 loader (lilo or loadlin) about how to pass options to the kernel at
1317 boot time.) This means that it is a good idea to say Y here if you
1318 intend to use this kernel on different machines.
1319
1320 More information about the internals of the Linux math coprocessor
1321 emulation can be found in <file:arch/x86/math-emu/README>.
1322
1323 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1324 kernel, it won't hurt.
1325
1326config MTRR
1327 bool "MTRR (Memory Type Range Register) support"
1328 ---help---
1329 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1330 the Memory Type Range Registers (MTRRs) may be used to control
1331 processor access to memory ranges. This is most useful if you have
1332 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1333 allows bus write transfers to be combined into a larger transfer
1334 before bursting over the PCI/AGP bus. This can increase performance
1335 of image write operations 2.5 times or more. Saying Y here creates a
1336 /proc/mtrr file which may be used to manipulate your processor's
1337 MTRRs. Typically the X server should use this.
1338
1339 This code has a reasonably generic interface so that similar
1340 control registers on other processors can be easily supported
1341 as well:
1342
1343 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1344 Registers (ARRs) which provide a similar functionality to MTRRs. For
1345 these, the ARRs are used to emulate the MTRRs.
1346 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1347 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1348 write-combining. All of these processors are supported by this code
1349 and it makes sense to say Y here if you have one of them.
1350
1351 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1352 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1353 can lead to all sorts of problems, so it's good to say Y here.
1354
1355 You can safely say Y even if your machine doesn't have MTRRs, you'll
1356 just add about 9 KB to your kernel.
1357
7225e751 1358 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1359
95ffa243 1360config MTRR_SANITIZER
2ffb3501 1361 def_bool y
95ffa243
YL
1362 prompt "MTRR cleanup support"
1363 depends on MTRR
8f9ca475 1364 ---help---
aba3728c
TG
1365 Convert MTRR layout from continuous to discrete, so X drivers can
1366 add writeback entries.
95ffa243 1367
aba3728c 1368 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1369 The largest mtrr entry size for a continuous block can be set with
aba3728c 1370 mtrr_chunk_size.
95ffa243 1371
2ffb3501 1372 If unsure, say Y.
95ffa243
YL
1373
1374config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1375 int "MTRR cleanup enable value (0-1)"
1376 range 0 1
1377 default "0"
95ffa243 1378 depends on MTRR_SANITIZER
8f9ca475 1379 ---help---
f5098d62 1380 Enable mtrr cleanup default value
95ffa243 1381
12031a62
YL
1382config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1383 int "MTRR cleanup spare reg num (0-7)"
1384 range 0 7
1385 default "1"
1386 depends on MTRR_SANITIZER
8f9ca475 1387 ---help---
12031a62 1388 mtrr cleanup spare entries default, it can be changed via
aba3728c 1389 mtrr_spare_reg_nr=N on the kernel command line.
506f1d07 1390
2e5d9c85 1391config X86_PAT
2a8a2719 1392 bool
2e5d9c85 1393 prompt "x86 PAT support"
2a8a2719 1394 depends on MTRR
8f9ca475 1395 ---help---
2e5d9c85 1396 Use PAT attributes to setup page level cache control.
042b78e4 1397
2e5d9c85 1398 PATs are the modern equivalents of MTRRs and are much more
1399 flexible than MTRRs.
1400
1401 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1402 spontaneous reboots) or a non-working video driver.
2e5d9c85 1403
1404 If unsure, say Y.
1405
506f1d07 1406config EFI
9ba16087 1407 bool "EFI runtime service support"
5b83683f 1408 depends on ACPI
506f1d07 1409 ---help---
8f9ca475
IM
1410 This enables the kernel to use EFI runtime services that are
1411 available (such as the EFI variable services).
506f1d07 1412
8f9ca475
IM
1413 This option is only useful on systems that have EFI firmware.
1414 In addition, you should use the latest ELILO loader available
1415 at <http://elilo.sourceforge.net> in order to take advantage
1416 of EFI runtime services. However, even with this option, the
1417 resultant kernel should continue to boot on existing non-EFI
1418 platforms.
506f1d07 1419
506f1d07 1420config SECCOMP
3c2362e6
HH
1421 def_bool y
1422 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1423 ---help---
506f1d07
SR
1424 This kernel feature is useful for number crunching applications
1425 that may need to compute untrusted bytecode during their
1426 execution. By using pipes or other transports made available to
1427 the process as file descriptors supporting the read/write
1428 syscalls, it's possible to isolate those applications in
1429 their own address space using seccomp. Once seccomp is
9c0bbee8 1430 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1431 and the task is only allowed to execute a few safe syscalls
1432 defined by each seccomp mode.
1433
1434 If unsure, say Y. Only embedded should say N here.
1435
113c5413
IM
1436config CC_STACKPROTECTOR_ALL
1437 bool
1438
506f1d07
SR
1439config CC_STACKPROTECTOR
1440 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
113c5413 1441 select CC_STACKPROTECTOR_ALL
8f9ca475
IM
1442 ---help---
1443 This option turns on the -fstack-protector GCC feature. This
113c5413
IM
1444 feature puts, at the beginning of functions, a canary value on
1445 the stack just before the return address, and validates
506f1d07
SR
1446 the value just before actually returning. Stack based buffer
1447 overflows (that need to overwrite this return address) now also
1448 overwrite the canary, which gets detected and the attack is then
1449 neutralized via a kernel panic.
1450
1451 This feature requires gcc version 4.2 or above, or a distribution
1452 gcc with the feature backported. Older versions are automatically
113c5413
IM
1453 detected and for those versions, this configuration option is
1454 ignored. (and a warning is printed during bootup)
506f1d07
SR
1455
1456source kernel/Kconfig.hz
1457
1458config KEXEC
1459 bool "kexec system call"
8f9ca475 1460 ---help---
506f1d07
SR
1461 kexec is a system call that implements the ability to shutdown your
1462 current kernel, and to start another kernel. It is like a reboot
1463 but it is independent of the system firmware. And like a reboot
1464 you can start any kernel with it, not just Linux.
1465
1466 The name comes from the similarity to the exec system call.
1467
1468 It is an ongoing process to be certain the hardware in a machine
1469 is properly shutdown, so do not be surprised if this code does not
1470 initially work for you. It may help to enable device hotplugging
1471 support. As of this writing the exact hardware interface is
1472 strongly in flux, so no good recommendation can be made.
1473
1474config CRASH_DUMP
04b69447 1475 bool "kernel crash dumps"
506f1d07 1476 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1477 ---help---
506f1d07
SR
1478 Generate crash dump after being started by kexec.
1479 This should be normally only set in special crash dump kernels
1480 which are loaded in the main kernel with kexec-tools into
1481 a specially reserved region and then later executed after
1482 a crash by kdump/kexec. The crash dump kernel must be compiled
1483 to a memory address not used by the main kernel or BIOS using
1484 PHYSICAL_START, or it must be built as a relocatable image
1485 (CONFIG_RELOCATABLE=y).
1486 For more details see Documentation/kdump/kdump.txt
1487
3ab83521
HY
1488config KEXEC_JUMP
1489 bool "kexec jump (EXPERIMENTAL)"
1490 depends on EXPERIMENTAL
fee7b0d8 1491 depends on KEXEC && HIBERNATION
8f9ca475 1492 ---help---
89081d17
HY
1493 Jump between original kernel and kexeced kernel and invoke
1494 code in physical address mode via KEXEC
3ab83521 1495
506f1d07
SR
1496config PHYSICAL_START
1497 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1498 default "0x1000000" if X86_NUMAQ
1499 default "0x200000" if X86_64
1500 default "0x100000"
8f9ca475 1501 ---help---
506f1d07
SR
1502 This gives the physical address where the kernel is loaded.
1503
1504 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1505 bzImage will decompress itself to above physical address and
1506 run from there. Otherwise, bzImage will run from the address where
1507 it has been loaded by the boot loader and will ignore above physical
1508 address.
1509
1510 In normal kdump cases one does not have to set/change this option
1511 as now bzImage can be compiled as a completely relocatable image
1512 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1513 address. This option is mainly useful for the folks who don't want
1514 to use a bzImage for capturing the crash dump and want to use a
1515 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1516 to be specifically compiled to run from a specific memory area
1517 (normally a reserved region) and this option comes handy.
1518
1519 So if you are using bzImage for capturing the crash dump, leave
1520 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1521 Otherwise if you plan to use vmlinux for capturing the crash dump
1522 change this value to start of the reserved region (Typically 16MB
1523 0x1000000). In other words, it can be set based on the "X" value as
1524 specified in the "crashkernel=YM@XM" command line boot parameter
1525 passed to the panic-ed kernel. Typically this parameter is set as
1526 crashkernel=64M@16M. Please take a look at
1527 Documentation/kdump/kdump.txt for more details about crash dumps.
1528
1529 Usage of bzImage for capturing the crash dump is recommended as
1530 one does not have to build two kernels. Same kernel can be used
1531 as production kernel and capture kernel. Above option should have
1532 gone away after relocatable bzImage support is introduced. But it
1533 is present because there are users out there who continue to use
1534 vmlinux for dump capture. This option should go away down the
1535 line.
1536
1537 Don't change this unless you know what you are doing.
1538
1539config RELOCATABLE
1540 bool "Build a relocatable kernel (EXPERIMENTAL)"
1541 depends on EXPERIMENTAL
8f9ca475 1542 ---help---
506f1d07
SR
1543 This builds a kernel image that retains relocation information
1544 so it can be loaded someplace besides the default 1MB.
1545 The relocations tend to make the kernel binary about 10% larger,
1546 but are discarded at runtime.
1547
1548 One use is for the kexec on panic case where the recovery kernel
1549 must live at a different physical address than the primary
1550 kernel.
1551
1552 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1553 it has been loaded at and the compile time physical address
1554 (CONFIG_PHYSICAL_START) is ignored.
1555
1556config PHYSICAL_ALIGN
1557 hex
1558 prompt "Alignment value to which kernel should be aligned" if X86_32
1559 default "0x100000" if X86_32
1560 default "0x200000" if X86_64
1561 range 0x2000 0x400000
8f9ca475 1562 ---help---
506f1d07
SR
1563 This value puts the alignment restrictions on physical address
1564 where kernel is loaded and run from. Kernel is compiled for an
1565 address which meets above alignment restriction.
1566
1567 If bootloader loads the kernel at a non-aligned address and
1568 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1569 address aligned to above value and run from there.
1570
1571 If bootloader loads the kernel at a non-aligned address and
1572 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1573 load address and decompress itself to the address it has been
1574 compiled for and run from there. The address for which kernel is
1575 compiled already meets above alignment restrictions. Hence the
1576 end result is that kernel runs from a physical address meeting
1577 above alignment restrictions.
1578
1579 Don't change this unless you know what you are doing.
1580
1581config HOTPLUG_CPU
7c13e6a3 1582 bool "Support for hot-pluggable CPUs"
4b19ed91 1583 depends on SMP && HOTPLUG
506f1d07 1584 ---help---
7c13e6a3
DS
1585 Say Y here to allow turning CPUs off and on. CPUs can be
1586 controlled through /sys/devices/system/cpu.
1587 ( Note: power management support will enable this option
1588 automatically on SMP systems. )
1589 Say N if you want to disable CPU hotplug.
506f1d07
SR
1590
1591config COMPAT_VDSO
3c2362e6
HH
1592 def_bool y
1593 prompt "Compat VDSO support"
af65d648 1594 depends on X86_32 || IA32_EMULATION
8f9ca475 1595 ---help---
af65d648 1596 Map the 32-bit VDSO to the predictable old-style address too.
506f1d07
SR
1597 ---help---
1598 Say N here if you are running a sufficiently recent glibc
1599 version (2.3.3 or later), to remove the high-mapped
1600 VDSO mapping and to exclusively use the randomized VDSO.
1601
1602 If unsure, say Y.
1603
516cbf37
TB
1604config CMDLINE_BOOL
1605 bool "Built-in kernel command line"
1606 default n
8f9ca475 1607 ---help---
516cbf37
TB
1608 Allow for specifying boot arguments to the kernel at
1609 build time. On some systems (e.g. embedded ones), it is
1610 necessary or convenient to provide some or all of the
1611 kernel boot arguments with the kernel itself (that is,
1612 to not rely on the boot loader to provide them.)
1613
1614 To compile command line arguments into the kernel,
1615 set this option to 'Y', then fill in the
1616 the boot arguments in CONFIG_CMDLINE.
1617
1618 Systems with fully functional boot loaders (i.e. non-embedded)
1619 should leave this option set to 'N'.
1620
1621config CMDLINE
1622 string "Built-in kernel command string"
1623 depends on CMDLINE_BOOL
1624 default ""
8f9ca475 1625 ---help---
516cbf37
TB
1626 Enter arguments here that should be compiled into the kernel
1627 image and used at boot time. If the boot loader provides a
1628 command line at boot time, it is appended to this string to
1629 form the full kernel command line, when the system boots.
1630
1631 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1632 change this behavior.
1633
1634 In most cases, the command line (whether built-in or provided
1635 by the boot loader) should specify the device for the root
1636 file system.
1637
1638config CMDLINE_OVERRIDE
1639 bool "Built-in command line overrides boot loader arguments"
1640 default n
1641 depends on CMDLINE_BOOL
8f9ca475 1642 ---help---
516cbf37
TB
1643 Set this option to 'Y' to have the kernel ignore the boot loader
1644 command line, and use ONLY the built-in command line.
1645
1646 This is used to work around broken boot loaders. This should
1647 be set to 'N' under normal conditions.
1648
506f1d07
SR
1649endmenu
1650
1651config ARCH_ENABLE_MEMORY_HOTPLUG
1652 def_bool y
1653 depends on X86_64 || (X86_32 && HIGHMEM)
1654
35551053
GH
1655config ARCH_ENABLE_MEMORY_HOTREMOVE
1656 def_bool y
1657 depends on MEMORY_HOTPLUG
1658
506f1d07
SR
1659config HAVE_ARCH_EARLY_PFN_TO_NID
1660 def_bool X86_64
1661 depends on NUMA
1662
da85f865 1663menu "Power management and ACPI options"
e279b6c1
SR
1664
1665config ARCH_HIBERNATION_HEADER
3c2362e6 1666 def_bool y
e279b6c1 1667 depends on X86_64 && HIBERNATION
e279b6c1
SR
1668
1669source "kernel/power/Kconfig"
1670
1671source "drivers/acpi/Kconfig"
1672
a6b68076
AK
1673config X86_APM_BOOT
1674 bool
1675 default y
1676 depends on APM || APM_MODULE
1677
e279b6c1
SR
1678menuconfig APM
1679 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 1680 depends on X86_32 && PM_SLEEP
e279b6c1
SR
1681 ---help---
1682 APM is a BIOS specification for saving power using several different
1683 techniques. This is mostly useful for battery powered laptops with
1684 APM compliant BIOSes. If you say Y here, the system time will be
1685 reset after a RESUME operation, the /proc/apm device will provide
1686 battery status information, and user-space programs will receive
1687 notification of APM "events" (e.g. battery status change).
1688
1689 If you select "Y" here, you can disable actual use of the APM
1690 BIOS by passing the "apm=off" option to the kernel at boot time.
1691
1692 Note that the APM support is almost completely disabled for
1693 machines with more than one CPU.
1694
1695 In order to use APM, you will need supporting software. For location
53471121 1696 and more information, read <file:Documentation/power/pm.txt> and the
e279b6c1
SR
1697 Battery Powered Linux mini-HOWTO, available from
1698 <http://www.tldp.org/docs.html#howto>.
1699
1700 This driver does not spin down disk drives (see the hdparm(8)
1701 manpage ("man 8 hdparm") for that), and it doesn't turn off
1702 VESA-compliant "green" monitors.
1703
1704 This driver does not support the TI 4000M TravelMate and the ACER
1705 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1706 desktop machines also don't have compliant BIOSes, and this driver
1707 may cause those machines to panic during the boot phase.
1708
1709 Generally, if you don't have a battery in your machine, there isn't
1710 much point in using this driver and you should say N. If you get
1711 random kernel OOPSes or reboots that don't seem to be related to
1712 anything, try disabling/enabling this option (or disabling/enabling
1713 APM in your BIOS).
1714
1715 Some other things you should try when experiencing seemingly random,
1716 "weird" problems:
1717
1718 1) make sure that you have enough swap space and that it is
1719 enabled.
1720 2) pass the "no-hlt" option to the kernel
1721 3) switch on floating point emulation in the kernel and pass
1722 the "no387" option to the kernel
1723 4) pass the "floppy=nodma" option to the kernel
1724 5) pass the "mem=4M" option to the kernel (thereby disabling
1725 all but the first 4 MB of RAM)
1726 6) make sure that the CPU is not over clocked.
1727 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1728 8) disable the cache from your BIOS settings
1729 9) install a fan for the video card or exchange video RAM
1730 10) install a better fan for the CPU
1731 11) exchange RAM chips
1732 12) exchange the motherboard.
1733
1734 To compile this driver as a module, choose M here: the
1735 module will be called apm.
1736
1737if APM
1738
1739config APM_IGNORE_USER_SUSPEND
1740 bool "Ignore USER SUSPEND"
8f9ca475 1741 ---help---
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1742 This option will ignore USER SUSPEND requests. On machines with a
1743 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1744 series notebooks, it is necessary to say Y because of a BIOS bug.
1745
1746config APM_DO_ENABLE
1747 bool "Enable PM at boot time"
1748 ---help---
1749 Enable APM features at boot time. From page 36 of the APM BIOS
1750 specification: "When disabled, the APM BIOS does not automatically
1751 power manage devices, enter the Standby State, enter the Suspend
1752 State, or take power saving steps in response to CPU Idle calls."
1753 This driver will make CPU Idle calls when Linux is idle (unless this
1754 feature is turned off -- see "Do CPU IDLE calls", below). This
1755 should always save battery power, but more complicated APM features
1756 will be dependent on your BIOS implementation. You may need to turn
1757 this option off if your computer hangs at boot time when using APM
1758 support, or if it beeps continuously instead of suspending. Turn
1759 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1760 T400CDT. This is off by default since most machines do fine without
1761 this feature.
1762
1763config APM_CPU_IDLE
1764 bool "Make CPU Idle calls when idle"
8f9ca475 1765 ---help---
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1766 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1767 On some machines, this can activate improved power savings, such as
1768 a slowed CPU clock rate, when the machine is idle. These idle calls
1769 are made after the idle loop has run for some length of time (e.g.,
1770 333 mS). On some machines, this will cause a hang at boot time or
1771 whenever the CPU becomes idle. (On machines with more than one CPU,
1772 this option does nothing.)
1773
1774config APM_DISPLAY_BLANK
1775 bool "Enable console blanking using APM"
8f9ca475 1776 ---help---
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1777 Enable console blanking using the APM. Some laptops can use this to
1778 turn off the LCD backlight when the screen blanker of the Linux
1779 virtual console blanks the screen. Note that this is only used by
1780 the virtual console screen blanker, and won't turn off the backlight
1781 when using the X Window system. This also doesn't have anything to
1782 do with your VESA-compliant power-saving monitor. Further, this
1783 option doesn't work for all laptops -- it might not turn off your
1784 backlight at all, or it might print a lot of errors to the console,
1785 especially if you are using gpm.
1786
1787config APM_ALLOW_INTS
1788 bool "Allow interrupts during APM BIOS calls"
8f9ca475 1789 ---help---
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1790 Normally we disable external interrupts while we are making calls to
1791 the APM BIOS as a measure to lessen the effects of a badly behaving
1792 BIOS implementation. The BIOS should reenable interrupts if it
1793 needs to. Unfortunately, some BIOSes do not -- especially those in
1794 many of the newer IBM Thinkpads. If you experience hangs when you
1795 suspend, try setting this to Y. Otherwise, say N.
1796
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1797endif # APM
1798
1799source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1800
1801source "drivers/cpuidle/Kconfig"
1802
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1803source "drivers/idle/Kconfig"
1804
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1805endmenu
1806
1807
1808menu "Bus options (PCI etc.)"
1809
1810config PCI
1ac97018 1811 bool "PCI support"
1c858087 1812 default y
e279b6c1 1813 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
8f9ca475 1814 ---help---
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1815 Find out whether you have a PCI motherboard. PCI is the name of a
1816 bus system, i.e. the way the CPU talks to the other stuff inside
1817 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1818 VESA. If you have PCI, say Y, otherwise N.
1819
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1820choice
1821 prompt "PCI access mode"
efefa6f6 1822 depends on X86_32 && PCI
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SR
1823 default PCI_GOANY
1824 ---help---
1825 On PCI systems, the BIOS can be used to detect the PCI devices and
1826 determine their configuration. However, some old PCI motherboards
1827 have BIOS bugs and may crash if this is done. Also, some embedded
1828 PCI-based systems don't have any BIOS at all. Linux can also try to
1829 detect the PCI hardware directly without using the BIOS.
1830
1831 With this option, you can specify how Linux should detect the
1832 PCI devices. If you choose "BIOS", the BIOS will be used,
1833 if you choose "Direct", the BIOS won't be used, and if you
1834 choose "MMConfig", then PCI Express MMCONFIG will be used.
1835 If you choose "Any", the kernel will try MMCONFIG, then the
1836 direct access method and falls back to the BIOS if that doesn't
1837 work. If unsure, go with the default, which is "Any".
1838
1839config PCI_GOBIOS
1840 bool "BIOS"
1841
1842config PCI_GOMMCONFIG
1843 bool "MMConfig"
1844
1845config PCI_GODIRECT
1846 bool "Direct"
1847
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1848config PCI_GOOLPC
1849 bool "OLPC"
1850 depends on OLPC
1851
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1852config PCI_GOANY
1853 bool "Any"
1854
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SR
1855endchoice
1856
1857config PCI_BIOS
3c2362e6 1858 def_bool y
efefa6f6 1859 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
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1860
1861# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1862config PCI_DIRECT
3c2362e6 1863 def_bool y
efefa6f6 1864 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
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1865
1866config PCI_MMCONFIG
3c2362e6 1867 def_bool y
e279b6c1 1868 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 1869
3ef0e1f8 1870config PCI_OLPC
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AS
1871 def_bool y
1872 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 1873
e279b6c1 1874config PCI_DOMAINS
3c2362e6 1875 def_bool y
e279b6c1 1876 depends on PCI
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SR
1877
1878config PCI_MMCONFIG
1879 bool "Support mmconfig PCI config space access"
1880 depends on X86_64 && PCI && ACPI
1881
1882config DMAR
1883 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
4cf2e75d 1884 depends on PCI_MSI && ACPI && EXPERIMENTAL
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SR
1885 help
1886 DMA remapping (DMAR) devices support enables independent address
1887 translations for Direct Memory Access (DMA) from devices.
1888 These DMA remapping devices are reported via ACPI tables
1889 and include PCI device scope covered by these DMA
1890 remapping devices.
1891
0cd5c3c8 1892config DMAR_DEFAULT_ON
f6be37fd 1893 def_bool y
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KM
1894 prompt "Enable DMA Remapping Devices by default"
1895 depends on DMAR
1896 help
1897 Selecting this option will enable a DMAR device at boot time if
1898 one is found. If this option is not selected, DMAR support can
1899 be enabled by passing intel_iommu=on to the kernel. It is
1900 recommended you say N here while the DMAR code remains
1901 experimental.
1902
e279b6c1 1903config DMAR_GFX_WA
3c2362e6
HH
1904 def_bool y
1905 prompt "Support for Graphics workaround"
e279b6c1 1906 depends on DMAR
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IM
1907 ---help---
1908 Current Graphics drivers tend to use physical address
1909 for DMA and avoid using DMA APIs. Setting this config
1910 option permits the IOMMU driver to set a unity map for
1911 all the OS-visible memory. Hence the driver can continue
1912 to use physical addresses for DMA.
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1913
1914config DMAR_FLOPPY_WA
3c2362e6 1915 def_bool y
e279b6c1 1916 depends on DMAR
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IM
1917 ---help---
1918 Floppy disk drivers are know to bypass DMA API calls
1919 thereby failing to work when IOMMU is enabled. This
1920 workaround will setup a 1:1 mapping for the first
1921 16M to make floppy (an ISA device) work.
e279b6c1 1922
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SS
1923config INTR_REMAP
1924 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1925 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
8f9ca475
IM
1926 ---help---
1927 Supports Interrupt remapping for IO-APIC and MSI devices.
1928 To use x2apic mode in the CPU's which support x2APIC enhancements or
1929 to support platforms with CPU's having > 8 bit APIC ID, say Y.
9fa8c481 1930
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SR
1931source "drivers/pci/pcie/Kconfig"
1932
1933source "drivers/pci/Kconfig"
1934
1935# x86_64 have no ISA slots, but do have ISA-style DMA.
1936config ISA_DMA_API
3c2362e6 1937 def_bool y
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SR
1938
1939if X86_32
1940
1941config ISA
1942 bool "ISA support"
8f9ca475 1943 ---help---
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SR
1944 Find out whether you have ISA slots on your motherboard. ISA is the
1945 name of a bus system, i.e. the way the CPU talks to the other stuff
1946 inside your box. Other bus systems are PCI, EISA, MicroChannel
1947 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1948 newer boards don't support it. If you have ISA, say Y, otherwise N.
1949
1950config EISA
1951 bool "EISA support"
1952 depends on ISA
1953 ---help---
1954 The Extended Industry Standard Architecture (EISA) bus was
1955 developed as an open alternative to the IBM MicroChannel bus.
1956
1957 The EISA bus provided some of the features of the IBM MicroChannel
1958 bus while maintaining backward compatibility with cards made for
1959 the older ISA bus. The EISA bus saw limited use between 1988 and
1960 1995 when it was made obsolete by the PCI bus.
1961
1962 Say Y here if you are building a kernel for an EISA-based machine.
1963
1964 Otherwise, say N.
1965
1966source "drivers/eisa/Kconfig"
1967
1968config MCA
72ee6ebb 1969 bool "MCA support"
8f9ca475 1970 ---help---
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SR
1971 MicroChannel Architecture is found in some IBM PS/2 machines and
1972 laptops. It is a bus system similar to PCI or ISA. See
1973 <file:Documentation/mca.txt> (and especially the web page given
1974 there) before attempting to build an MCA bus kernel.
1975
1976source "drivers/mca/Kconfig"
1977
1978config SCx200
1979 tristate "NatSemi SCx200 support"
8f9ca475 1980 ---help---
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SR
1981 This provides basic support for National Semiconductor's
1982 (now AMD's) Geode processors. The driver probes for the
1983 PCI-IDs of several on-chip devices, so its a good dependency
1984 for other scx200_* drivers.
1985
1986 If compiled as a module, the driver is named scx200.
1987
1988config SCx200HR_TIMER
1989 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1990 depends on SCx200 && GENERIC_TIME
1991 default y
8f9ca475 1992 ---help---
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SR
1993 This driver provides a clocksource built upon the on-chip
1994 27MHz high-resolution timer. Its also a workaround for
1995 NSC Geode SC-1100's buggy TSC, which loses time when the
1996 processor goes idle (as is done by the scheduler). The
1997 other workaround is idle=poll boot option.
1998
1999config GEODE_MFGPT_TIMER
3c2362e6
HH
2000 def_bool y
2001 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
e279b6c1 2002 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
8f9ca475 2003 ---help---
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SR
2004 This driver provides a clock event source based on the MFGPT
2005 timer(s) in the CS5535 and CS5536 companion chip for the geode.
2006 MFGPTs have a better resolution and max interval than the
2007 generic PIT, and are suitable for use as high-res timers.
2008
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AS
2009config OLPC
2010 bool "One Laptop Per Child support"
2011 default n
8f9ca475 2012 ---help---
3ef0e1f8
AS
2013 Add support for detecting the unique features of the OLPC
2014 XO hardware.
2015
bc0120fd
SR
2016endif # X86_32
2017
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SR
2018config K8_NB
2019 def_bool y
bc0120fd 2020 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
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SR
2021
2022source "drivers/pcmcia/Kconfig"
2023
2024source "drivers/pci/hotplug/Kconfig"
2025
2026endmenu
2027
2028
2029menu "Executable file formats / Emulations"
2030
2031source "fs/Kconfig.binfmt"
2032
2033config IA32_EMULATION
2034 bool "IA32 Emulation"
2035 depends on X86_64
a97f52e6 2036 select COMPAT_BINFMT_ELF
8f9ca475 2037 ---help---
e279b6c1
SR
2038 Include code to run 32-bit programs under a 64-bit kernel. You should
2039 likely turn this on, unless you're 100% sure that you don't have any
2040 32-bit programs left.
2041
2042config IA32_AOUT
8f9ca475
IM
2043 tristate "IA32 a.out support"
2044 depends on IA32_EMULATION
2045 ---help---
2046 Support old a.out binaries in the 32bit emulation.
e279b6c1
SR
2047
2048config COMPAT
3c2362e6 2049 def_bool y
e279b6c1 2050 depends on IA32_EMULATION
e279b6c1
SR
2051
2052config COMPAT_FOR_U64_ALIGNMENT
2053 def_bool COMPAT
2054 depends on X86_64
2055
2056config SYSVIPC_COMPAT
3c2362e6 2057 def_bool y
b8992195 2058 depends on COMPAT && SYSVIPC
e279b6c1
SR
2059
2060endmenu
2061
2062
e5beae16
KP
2063config HAVE_ATOMIC_IOMAP
2064 def_bool y
2065 depends on X86_32
2066
e279b6c1
SR
2067source "net/Kconfig"
2068
2069source "drivers/Kconfig"
2070
2071source "drivers/firmware/Kconfig"
2072
2073source "fs/Kconfig"
2074
e279b6c1
SR
2075source "arch/x86/Kconfig.debug"
2076
2077source "security/Kconfig"
2078
2079source "crypto/Kconfig"
2080
edf88417
AK
2081source "arch/x86/kvm/Kconfig"
2082
e279b6c1 2083source "lib/Kconfig"