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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
51b26ada
LT
50config OUTPUT_FORMAT
51 string
52 default "elf32-i386" if X86_32
53 default "elf64-x86-64" if X86_64
54
73531905 55config ARCH_DEFCONFIG
b9b39bfb 56 string
73531905
SR
57 default "arch/x86/configs/i386_defconfig" if X86_32
58 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 59
8d5fffb9 60config GENERIC_TIME
3c2362e6 61 def_bool y
8d5fffb9
SR
62
63config GENERIC_CMOS_UPDATE
3c2362e6 64 def_bool y
8d5fffb9
SR
65
66config CLOCKSOURCE_WATCHDOG
3c2362e6 67 def_bool y
8d5fffb9
SR
68
69config GENERIC_CLOCKEVENTS
3c2362e6 70 def_bool y
8d5fffb9
SR
71
72config GENERIC_CLOCKEVENTS_BROADCAST
3c2362e6 73 def_bool y
8d5fffb9
SR
74 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
75
76config LOCKDEP_SUPPORT
3c2362e6 77 def_bool y
8d5fffb9
SR
78
79config STACKTRACE_SUPPORT
3c2362e6 80 def_bool y
8d5fffb9 81
aa7d9350
HC
82config HAVE_LATENCYTOP_SUPPORT
83 def_bool y
84
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CL
85config FAST_CMPXCHG_LOCAL
86 bool
87 default y
88
8d5fffb9 89config MMU
3c2362e6 90 def_bool y
8d5fffb9
SR
91
92config ZONE_DMA
3c2362e6 93 def_bool y
8d5fffb9 94
8d5fffb9
SR
95config SBUS
96 bool
97
98config GENERIC_ISA_DMA
3c2362e6 99 def_bool y
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SR
100
101config GENERIC_IOMAP
3c2362e6 102 def_bool y
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SR
103
104config GENERIC_BUG
3c2362e6 105 def_bool y
8d5fffb9 106 depends on BUG
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107 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
108
109config GENERIC_BUG_RELATIVE_POINTERS
110 bool
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SR
111
112config GENERIC_HWEIGHT
3c2362e6 113 def_bool y
8d5fffb9 114
a6082959 115config GENERIC_GPIO
9ba16087 116 bool
a6082959 117
8d5fffb9 118config ARCH_MAY_HAVE_PC_FDC
3c2362e6 119 def_bool y
8d5fffb9 120
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121config RWSEM_GENERIC_SPINLOCK
122 def_bool !X86_XADD
123
124config RWSEM_XCHGADD_ALGORITHM
125 def_bool X86_XADD
126
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VP
127config ARCH_HAS_CPU_IDLE_WAIT
128 def_bool y
129
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SR
130config GENERIC_CALIBRATE_DELAY
131 def_bool y
132
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133config GENERIC_TIME_VSYSCALL
134 bool
135 default X86_64
136
9a0b8415 137config ARCH_HAS_CPU_RELAX
138 def_bool y
139
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140config ARCH_HAS_DEFAULT_IDLE
141 def_bool y
142
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PE
143config ARCH_HAS_CACHE_LINE_SIZE
144 def_bool y
145
dd5af90a 146config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 147 def_bool y
b32ef636 148
11124411
TH
149config HAVE_DYNAMIC_PER_CPU_AREA
150 def_bool y
151
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152config HAVE_CPUMASK_OF_CPU_MAP
153 def_bool X86_64_SMP
154
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JB
155config ARCH_HIBERNATION_POSSIBLE
156 def_bool y
801e4062 157
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JB
158config ARCH_SUSPEND_POSSIBLE
159 def_bool y
f4cb5700 160
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SR
161config ZONE_DMA32
162 bool
163 default X86_64
164
165config ARCH_POPULATES_NODE_MAP
166 def_bool y
167
168config AUDIT_ARCH
169 bool
170 default X86_64
171
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172config ARCH_SUPPORTS_OPTIMIZED_INLINING
173 def_bool y
174
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175config ARCH_SUPPORTS_DEBUG_PAGEALLOC
176 def_bool y
177
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178# Use the generic interrupt handling code in kernel/irq/:
179config GENERIC_HARDIRQS
180 bool
181 default y
182
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183config GENERIC_HARDIRQS_NO__DO_IRQ
184 def_bool y
185
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186config GENERIC_IRQ_PROBE
187 bool
188 default y
189
190config GENERIC_PENDING_IRQ
191 bool
192 depends on GENERIC_HARDIRQS && SMP
193 default y
194
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JB
195config USE_GENERIC_SMP_HELPERS
196 def_bool y
197 depends on SMP
198
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SR
199config X86_32_SMP
200 def_bool y
201 depends on X86_32 && SMP
202
203config X86_64_SMP
204 def_bool y
205 depends on X86_64 && SMP
206
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SR
207config X86_HT
208 bool
ee0011a7 209 depends on SMP
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210 default y
211
212config X86_TRAMPOLINE
213 bool
3e5095d1 214 depends on SMP || (64BIT && ACPI_SLEEP)
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SR
215 default y
216
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217config X86_32_LAZY_GS
218 def_bool y
60a5317f 219 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 220
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SR
221config KTIME_SCALAR
222 def_bool X86_32
506f1d07 223source "init/Kconfig"
dc52ddc0 224source "kernel/Kconfig.freezer"
8d5fffb9 225
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SR
226menu "Processor type and features"
227
228source "kernel/time/Kconfig"
229
230config SMP
231 bool "Symmetric multi-processing support"
232 ---help---
233 This enables support for systems with more than one CPU. If you have
234 a system with only one CPU, like most personal computers, say N. If
235 you have a system with more than one CPU, say Y.
236
237 If you say N here, the kernel will run on single and multiprocessor
238 machines, but will use only one CPU of a multiprocessor machine. If
239 you say Y here, the kernel will run on many, but not all,
240 singleprocessor machines. On a singleprocessor machine, the kernel
241 will run faster if you say N here.
242
243 Note that if you say Y here and choose architecture "586" or
244 "Pentium" under "Processor family", the kernel will not work on 486
245 architectures. Similarly, multiprocessor kernels for the "PPro"
246 architecture may not work on all Pentium based boards.
247
248 People using multiprocessor machines who say Y here should also say
249 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
250 Management" code will be disabled if you say Y here.
251
03502faa 252 See also <file:Documentation/i386/IO-APIC.txt>,
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SR
253 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
254 <http://www.tldp.org/docs.html#howto>.
255
256 If you don't know what to do here, say N.
257
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258config X86_X2APIC
259 bool "Support x2apic"
f7d7f866 260 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
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261 ---help---
262 This enables x2apic support on CPUs that have this feature.
263
264 This allows 32-bit apic IDs (so it can support very large systems),
265 and accesses the local apic via MSRs not via mmio.
266
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267 If you don't know what to do here, say N.
268
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269config SPARSE_IRQ
270 bool "Support sparse irq numbering"
17483a1f 271 depends on PCI_MSI || HT_IRQ
8f9ca475 272 ---help---
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273 This enables support for sparse irqs. This is useful for distro
274 kernels that want to define a high CONFIG_NR_CPUS value but still
275 want to have low kernel memory footprint on smaller machines.
0b8f1efa 276
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IM
277 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
278 out the irq_desc[] array in a more NUMA-friendly way. )
279
280 If you don't know what to do here, say N.
0b8f1efa 281
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282config NUMA_IRQ_DESC
283 def_bool y
b9098957 284 depends on SPARSE_IRQ && NUMA
48a1b10a 285
6695c85b 286config X86_MPPARSE
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JB
287 bool "Enable MPS table" if ACPI
288 default y
5ab74722 289 depends on X86_LOCAL_APIC
8f9ca475 290 ---help---
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291 For old smp systems that do not have proper acpi support. Newer systems
292 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 293
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294config X86_BIGSMP
295 bool "Support for big SMP systems with more than 8 CPUs"
296 depends on X86_32 && SMP
8f9ca475 297 ---help---
26f7ef14 298 This option is needed for the systems that have more than 8 CPUs
506f1d07 299
8425091f 300if X86_32
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RT
301config X86_EXTENDED_PLATFORM
302 bool "Support for extended (non-PC) x86 platforms"
303 default y
8f9ca475 304 ---help---
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IM
305 If you disable this option then the kernel will only support
306 standard PC platforms. (which covers the vast majority of
307 systems out there.)
308
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RT
309 If you enable this option then you'll be able to select support
310 for the following (non-PC) 32 bit x86 platforms:
311 AMD Elan
312 NUMAQ (IBM/Sequent)
313 RDC R-321x SoC
314 SGI 320/540 (Visual Workstation)
315 Summit/EXA (IBM x440)
316 Unisys ES7000 IA32 series
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IM
317
318 If you have one of these systems, or if you want to build a
319 generic distribution kernel, say Y here - otherwise say N.
8425091f 320endif
06ac8346 321
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322if X86_64
323config X86_EXTENDED_PLATFORM
324 bool "Support for extended (non-PC) x86 platforms"
325 default y
326 ---help---
327 If you disable this option then the kernel will only support
328 standard PC platforms. (which covers the vast majority of
329 systems out there.)
330
331 If you enable this option then you'll be able to select support
332 for the following (non-PC) 64 bit x86 platforms:
333 ScaleMP vSMP
334 SGI Ultraviolet
335
336 If you have one of these systems, or if you want to build a
337 generic distribution kernel, say Y here - otherwise say N.
338endif
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339# This is an alphabetically sorted list of 64 bit extended platforms
340# Please maintain the alphabetic order if and when there are additions
506f1d07 341
c5c606d9
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342config X86_VSMP
343 bool "ScaleMP vSMP"
344 select PARAVIRT
345 depends on X86_64 && PCI
346 depends on X86_EXTENDED_PLATFORM
8f9ca475 347 ---help---
c5c606d9
RT
348 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
349 supposed to run on these EM64T-based machines. Only choose this option
350 if you have one of these machines.
5e3a77e9 351
03b48632
NP
352config X86_UV
353 bool "SGI Ultraviolet"
354 depends on X86_64
c5c606d9 355 depends on X86_EXTENDED_PLATFORM
54c28d29 356 depends on NUMA
9d6c26e7 357 depends on X86_X2APIC
8f9ca475 358 ---help---
03b48632
NP
359 This option is needed in order to support SGI Ultraviolet systems.
360 If you don't have one of these, you should say N here.
361
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RT
362# Following is an alphabetically sorted list of 32 bit extended platforms
363# Please maintain the alphabetic order if and when there are additions
506f1d07
SR
364
365config X86_ELAN
366 bool "AMD Elan"
367 depends on X86_32
c5c606d9 368 depends on X86_EXTENDED_PLATFORM
8f9ca475 369 ---help---
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SR
370 Select this for an AMD Elan processor.
371
372 Do not use this option for K6/Athlon/Opteron processors!
373
374 If unsure, choose "PC-compatible" instead.
375
c5c606d9
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376config X86_RDC321X
377 bool "RDC R-321x SoC"
506f1d07 378 depends on X86_32
c5c606d9
RT
379 depends on X86_EXTENDED_PLATFORM
380 select M486
381 select X86_REBOOTFIXUPS
382 ---help---
383 This option is needed for RDC R-321x system-on-chip, also known
384 as R-8610-(G).
385 If you don't have one of these chips, you should say N here.
386
e0c7ae37 387config X86_32_NON_STANDARD
9c398017
IM
388 bool "Support non-standard 32-bit SMP architectures"
389 depends on X86_32 && SMP
c5c606d9 390 depends on X86_EXTENDED_PLATFORM
8f9ca475
IM
391 ---help---
392 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
d49c4288
YL
393 subarchitectures. It is intended for a generic binary kernel.
394 if you select them all, kernel will probe it one by one. and will
395 fallback to default.
396
c5c606d9 397# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 398
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SR
399config X86_NUMAQ
400 bool "NUMAQ (IBM/Sequent)"
e0c7ae37 401 depends on X86_32_NON_STANDARD
506f1d07 402 select NUMA
9c398017 403 select X86_MPPARSE
8f9ca475 404 ---help---
d49c4288
YL
405 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
406 NUMA multiquad box. This changes the way that processors are
407 bootstrapped, and uses Clustered Logical APIC addressing mode instead
408 of Flat Logical. You will need a new lynxer.elf file to flash your
409 firmware with - send email to <Martin.Bligh@us.ibm.com>.
506f1d07 410
1b84e1c8
IM
411config X86_VISWS
412 bool "SGI 320/540 (Visual Workstation)"
c5c606d9
RT
413 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
414 depends on X86_32_NON_STANDARD
415 ---help---
1b84e1c8
IM
416 The SGI Visual Workstation series is an IA32-based workstation
417 based on SGI systems chips with some legacy PC hardware attached.
418
419 Say Y here to create a kernel to run on the SGI 320 or 540.
420
421 A kernel compiled for the Visual Workstation will run on general
422 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
423
9c398017
IM
424config X86_SUMMIT
425 bool "Summit/EXA (IBM x440)"
e0c7ae37 426 depends on X86_32_NON_STANDARD
8f9ca475 427 ---help---
9c398017
IM
428 This option is needed for IBM systems that use the Summit/EXA chipset.
429 In particular, it is needed for the x440.
1f972768 430
9c398017 431config X86_ES7000
c5c606d9 432 bool "Unisys ES7000 IA32 series"
26f7ef14 433 depends on X86_32_NON_STANDARD && X86_BIGSMP
8f9ca475 434 ---help---
9c398017
IM
435 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
436 supposed to run on an IA32-based Unisys ES7000 system.
437
ae1e9130 438config SCHED_OMIT_FRAME_POINTER
3c2362e6
HH
439 def_bool y
440 prompt "Single-depth WCHAN output"
a87d0914 441 depends on X86
8f9ca475 442 ---help---
506f1d07
SR
443 Calculate simpler /proc/<PID>/wchan values. If this option
444 is disabled then wchan values will recurse back to the
445 caller function. This provides more accurate wchan values,
446 at the expense of slightly more scheduling overhead.
447
448 If in doubt, say "Y".
449
506f1d07
SR
450menuconfig PARAVIRT_GUEST
451 bool "Paravirtualized guest support"
8f9ca475 452 ---help---
506f1d07
SR
453 Say Y here to get to see options related to running Linux under
454 various hypervisors. This option alone does not add any kernel code.
455
456 If you say N, all options in this submenu will be skipped and disabled.
457
458if PARAVIRT_GUEST
459
460source "arch/x86/xen/Kconfig"
461
462config VMI
463 bool "VMI Guest support"
464 select PARAVIRT
42d545c9 465 depends on X86_32
8f9ca475 466 ---help---
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SR
467 VMI provides a paravirtualized interface to the VMware ESX server
468 (it could be used by other hypervisors in theory too, but is not
469 at the moment), by linking the kernel to a GPL-ed ROM module
470 provided by the hypervisor.
471
790c73f6
GOC
472config KVM_CLOCK
473 bool "KVM paravirtualized clock"
474 select PARAVIRT
f6e16d5a 475 select PARAVIRT_CLOCK
8f9ca475 476 ---help---
790c73f6
GOC
477 Turning on this option will allow you to run a paravirtualized clock
478 when running over the KVM hypervisor. Instead of relying on a PIT
479 (or probably other) emulation by the underlying device model, the host
480 provides the guest with timing infrastructure such as time of day, and
481 system time
482
0cf1bfd2
MT
483config KVM_GUEST
484 bool "KVM Guest support"
485 select PARAVIRT
8f9ca475
IM
486 ---help---
487 This option enables various optimizations for running under the KVM
488 hypervisor.
0cf1bfd2 489
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SR
490source "arch/x86/lguest/Kconfig"
491
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EPH
492config PARAVIRT
493 bool "Enable paravirtualization code"
8f9ca475 494 ---help---
e61bd94a
EPH
495 This changes the kernel so it can modify itself when it is run
496 under a hypervisor, potentially improving performance significantly
497 over full virtualization. However, when run without a hypervisor
498 the kernel is theoretically slower and slightly larger.
499
b4ecc126
JF
500config PARAVIRT_SPINLOCKS
501 bool "Paravirtualization layer for spinlocks"
502 depends on PARAVIRT && SMP && EXPERIMENTAL
503 ---help---
504 Paravirtualized spinlocks allow a pvops backend to replace the
505 spinlock implementation with something virtualization-friendly
506 (for example, block the virtual CPU rather than spinning).
507
508 Unfortunately the downside is an up to 5% performance hit on
509 native kernels, with various workloads.
510
511 If you are unsure how to answer this question, answer N.
512
7af192c9
GH
513config PARAVIRT_CLOCK
514 bool
515 default n
516
506f1d07
SR
517endif
518
97349135 519config PARAVIRT_DEBUG
8f9ca475
IM
520 bool "paravirt-ops debugging"
521 depends on PARAVIRT && DEBUG_KERNEL
522 ---help---
523 Enable to debug paravirt_ops internals. Specifically, BUG if
524 a paravirt_op is missing when it is called.
97349135 525
03273184
YL
526config MEMTEST
527 bool "Memtest"
8f9ca475 528 ---help---
c64df707 529 This option adds a kernel parameter 'memtest', which allows memtest
03273184 530 to be set.
8f9ca475
IM
531 memtest=0, mean disabled; -- default
532 memtest=1, mean do 1 test pattern;
533 ...
534 memtest=4, mean do 4 test patterns.
aba3728c 535 If you are unsure how to answer this question, answer N.
506f1d07
SR
536
537config X86_SUMMIT_NUMA
3c2362e6 538 def_bool y
e0c7ae37 539 depends on X86_32 && NUMA && X86_32_NON_STANDARD
506f1d07
SR
540
541config X86_CYCLONE_TIMER
3c2362e6 542 def_bool y
e0c7ae37 543 depends on X86_32_NON_STANDARD
506f1d07 544
506f1d07
SR
545source "arch/x86/Kconfig.cpu"
546
547config HPET_TIMER
3c2362e6 548 def_bool X86_64
506f1d07 549 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
550 ---help---
551 Use the IA-PC HPET (High Precision Event Timer) to manage
552 time in preference to the PIT and RTC, if a HPET is
553 present.
554 HPET is the next generation timer replacing legacy 8254s.
555 The HPET provides a stable time base on SMP
556 systems, unlike the TSC, but it is more expensive to access,
557 as it is off-chip. You can find the HPET spec at
558 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
506f1d07 559
8f9ca475
IM
560 You can safely choose Y here. However, HPET will only be
561 activated if the platform and the BIOS support this feature.
562 Otherwise the 8254 will be used for timing services.
506f1d07 563
8f9ca475 564 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
565
566config HPET_EMULATE_RTC
3c2362e6 567 def_bool y
9d8af78b 568 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07
SR
569
570# Mark as embedded because too many people got it wrong.
571# The code disables itself when not needed.
7ae9392c
TP
572config DMI
573 default y
574 bool "Enable DMI scanning" if EMBEDDED
8f9ca475 575 ---help---
7ae9392c
TP
576 Enabled scanning of DMI to identify machine quirks. Say Y
577 here unless you have verified that your setup is not
578 affected by entries in the DMI blacklist. Required by PNP
579 BIOS code.
580
506f1d07
SR
581config GART_IOMMU
582 bool "GART IOMMU support" if EMBEDDED
583 default y
584 select SWIOTLB
585 select AGP
586 depends on X86_64 && PCI
8f9ca475 587 ---help---
506f1d07
SR
588 Support for full DMA access of devices with 32bit memory access only
589 on systems with more than 3GB. This is usually needed for USB,
590 sound, many IDE/SATA chipsets and some other devices.
591 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
592 based hardware IOMMU and a software bounce buffer based IOMMU used
593 on Intel systems and as fallback.
594 The code is only active when needed (enough memory and limited
595 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
596 too.
597
598config CALGARY_IOMMU
599 bool "IBM Calgary IOMMU support"
600 select SWIOTLB
601 depends on X86_64 && PCI && EXPERIMENTAL
8f9ca475 602 ---help---
506f1d07
SR
603 Support for hardware IOMMUs in IBM's xSeries x366 and x460
604 systems. Needed to run systems with more than 3GB of memory
605 properly with 32-bit PCI devices that do not support DAC
606 (Double Address Cycle). Calgary also supports bus level
607 isolation, where all DMAs pass through the IOMMU. This
608 prevents them from going anywhere except their intended
609 destination. This catches hard-to-find kernel bugs and
610 mis-behaving drivers and devices that do not use the DMA-API
611 properly to set up their DMA buffers. The IOMMU can be
612 turned off at boot time with the iommu=off parameter.
613 Normally the kernel will make the right choice by itself.
614 If unsure, say Y.
615
616config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
617 def_bool y
618 prompt "Should Calgary be enabled by default?"
506f1d07 619 depends on CALGARY_IOMMU
8f9ca475 620 ---help---
506f1d07
SR
621 Should Calgary be enabled by default? if you choose 'y', Calgary
622 will be used (if it exists). If you choose 'n', Calgary will not be
623 used even if it exists. If you choose 'n' and would like to use
624 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
625 If unsure, say Y.
626
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JR
627config AMD_IOMMU
628 bool "AMD IOMMU support"
07c40e8a 629 select SWIOTLB
a80dc3e0 630 select PCI_MSI
24d2ba0a 631 depends on X86_64 && PCI && ACPI
8f9ca475 632 ---help---
18d22200
JR
633 With this option you can enable support for AMD IOMMU hardware in
634 your system. An IOMMU is a hardware component which provides
635 remapping of DMA memory accesses from devices. With an AMD IOMMU you
636 can isolate the the DMA memory of different devices and protect the
637 system from misbehaving device drivers or hardware.
638
639 You can find out if your system has an AMD IOMMU if you look into
640 your BIOS for an option to enable it or if you have an IVRS ACPI
641 table.
2b188723 642
2e117604
JR
643config AMD_IOMMU_STATS
644 bool "Export AMD IOMMU statistics to debugfs"
645 depends on AMD_IOMMU
646 select DEBUG_FS
8f9ca475 647 ---help---
2e117604
JR
648 This option enables code in the AMD IOMMU driver to collect various
649 statistics about whats happening in the driver and exports that
650 information to userspace via debugfs.
651 If unsure, say N.
652
506f1d07
SR
653# need this always selected by IOMMU for the VIA workaround
654config SWIOTLB
a1afd01c 655 def_bool y if X86_64
8f9ca475 656 ---help---
506f1d07
SR
657 Support for software bounce buffers used on x86-64 systems
658 which don't have a hardware IOMMU (e.g. the current generation
659 of Intel's x86-64 CPUs). Using this PCI devices which can only
660 access 32-bits of memory can be used on systems with more than
661 3 GB of memory. If unsure, say Y.
662
a8522509 663config IOMMU_HELPER
18b743dc 664 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
d25e26b6 665
1aaf1183
JR
666config IOMMU_API
667 def_bool (AMD_IOMMU || DMAR)
668
1184dc2f
MT
669config MAXSMP
670 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
36f5101a
MT
671 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
672 select CPUMASK_OFFSTACK
1184dc2f 673 default n
8f9ca475 674 ---help---
1184dc2f
MT
675 Configure maximum number of CPUS and NUMA Nodes for this architecture.
676 If unsure, say N.
506f1d07
SR
677
678config NR_CPUS
36f5101a 679 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 680 range 2 8 if SMP && X86_32 && !X86_BIGSMP
36f5101a 681 range 2 512 if SMP && !MAXSMP
78637a97 682 default "1" if !SMP
d25e26b6 683 default "4096" if MAXSMP
78637a97
MT
684 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
685 default "8" if SMP
8f9ca475 686 ---help---
506f1d07 687 This allows you to specify the maximum number of CPUs which this
d25e26b6 688 kernel will support. The maximum supported value is 512 and the
506f1d07
SR
689 minimum value which makes sense is 2.
690
691 This is purely to save memory - each supported CPU adds
692 approximately eight kilobytes to the kernel image.
693
694config SCHED_SMT
695 bool "SMT (Hyperthreading) scheduler support"
b089c12b 696 depends on X86_HT
8f9ca475 697 ---help---
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SR
698 SMT scheduler support improves the CPU scheduler's decision making
699 when dealing with Intel Pentium 4 chips with HyperThreading at a
700 cost of slightly increased overhead in some places. If unsure say
701 N here.
702
703config SCHED_MC
3c2362e6
HH
704 def_bool y
705 prompt "Multi-core scheduler support"
b089c12b 706 depends on X86_HT
8f9ca475 707 ---help---
506f1d07
SR
708 Multi-core scheduler support improves the CPU scheduler's decision
709 making when dealing with multi-core CPU chips at a cost of slightly
710 increased overhead in some places. If unsure say N here.
711
712source "kernel/Kconfig.preempt"
713
714config X86_UP_APIC
715 bool "Local APIC support on uniprocessors"
e0c7ae37 716 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 717 ---help---
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SR
718 A local APIC (Advanced Programmable Interrupt Controller) is an
719 integrated interrupt controller in the CPU. If you have a single-CPU
720 system which has a processor with a local APIC, you can say Y here to
721 enable and use it. If you say Y here even though your machine doesn't
722 have a local APIC, then the kernel will still run with no slowdown at
723 all. The local APIC supports CPU-generated self-interrupts (timer,
724 performance counters), and the NMI watchdog which detects hard
725 lockups.
726
727config X86_UP_IOAPIC
728 bool "IO-APIC support on uniprocessors"
729 depends on X86_UP_APIC
8f9ca475 730 ---help---
506f1d07
SR
731 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
732 SMP-capable replacement for PC-style interrupt controllers. Most
733 SMP systems and many recent uniprocessor systems have one.
734
735 If you have a single-CPU system with an IO-APIC, you can say Y here
736 to use it. If you say Y here even though your machine doesn't have
737 an IO-APIC, then the kernel will still run with no slowdown at all.
738
739config X86_LOCAL_APIC
3c2362e6 740 def_bool y
e0c7ae37 741 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
ee06094f 742 select HAVE_PERF_COUNTERS if (!M386 && !M486)
506f1d07
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
41b9eb26
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
792config X86_MCE_INTEL
3c2362e6
HH
793 def_bool y
794 prompt "Intel MCE features"
506f1d07 795 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
8f9ca475 796 ---help---
506f1d07
SR
797 Additional support for intel specific MCE features such as
798 the thermal monitor.
799
800config X86_MCE_AMD
3c2362e6
HH
801 def_bool y
802 prompt "AMD MCE features"
506f1d07 803 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
8f9ca475 804 ---help---
506f1d07
SR
805 Additional support for AMD specific MCE features such as
806 the DRAM Error Threshold.
807
b2762686
AK
808config X86_MCE_THRESHOLD
809 depends on X86_MCE_AMD || X86_MCE_INTEL
810 bool
811 default y
812
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SR
813config X86_MCE_NONFATAL
814 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
815 depends on X86_32 && X86_MCE
8f9ca475 816 ---help---
506f1d07
SR
817 Enabling this feature starts a timer that triggers every 5 seconds which
818 will look at the machine check registers to see if anything happened.
819 Non-fatal problems automatically get corrected (but still logged).
820 Disable this if you don't want to see these messages.
821 Seeing the messages this option prints out may be indicative of dying
822 or out-of-spec (ie, overclocked) hardware.
823 This option only does something on certain CPUs.
824 (AMD Athlon/Duron and Intel Pentium 4)
825
826config X86_MCE_P4THERMAL
827 bool "check for P4 thermal throttling interrupt."
efefa6f6 828 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
8f9ca475 829 ---help---
506f1d07
SR
830 Enabling this feature will cause a message to be printed when the P4
831 enters thermal throttling.
832
833config VM86
834 bool "Enable VM86 support" if EMBEDDED
835 default y
836 depends on X86_32
8f9ca475
IM
837 ---help---
838 This option is required by programs like DOSEMU to run 16-bit legacy
506f1d07 839 code on X86 processors. It also may be needed by software like
8f9ca475
IM
840 XFree86 to initialize some video cards via BIOS. Disabling this
841 option saves about 6k.
506f1d07
SR
842
843config TOSHIBA
844 tristate "Toshiba Laptop support"
845 depends on X86_32
846 ---help---
847 This adds a driver to safely access the System Management Mode of
848 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
849 not work on models with a Phoenix BIOS. The System Management Mode
850 is used to set the BIOS and power saving options on Toshiba portables.
851
852 For information on utilities to make use of this driver see the
853 Toshiba Linux utilities web site at:
854 <http://www.buzzard.org.uk/toshiba/>.
855
856 Say Y if you intend to run this kernel on a Toshiba portable.
857 Say N otherwise.
858
859config I8K
860 tristate "Dell laptop support"
506f1d07
SR
861 ---help---
862 This adds a driver to safely access the System Management Mode
863 of the CPU on the Dell Inspiron 8000. The System Management Mode
864 is used to read cpu temperature and cooling fan status and to
865 control the fans on the I8K portables.
866
867 This driver has been tested only on the Inspiron 8000 but it may
868 also work with other Dell laptops. You can force loading on other
869 models by passing the parameter `force=1' to the module. Use at
870 your own risk.
871
872 For information on utilities to make use of this driver see the
873 I8K Linux utilities web site at:
874 <http://people.debian.org/~dz/i8k/>
875
876 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
877 Say N otherwise.
878
879config X86_REBOOTFIXUPS
9ba16087
JB
880 bool "Enable X86 board specific fixups for reboot"
881 depends on X86_32
506f1d07
SR
882 ---help---
883 This enables chipset and/or board specific fixups to be done
884 in order to get reboot to work correctly. This is only needed on
885 some combinations of hardware and BIOS. The symptom, for which
886 this config is intended, is when reboot ends with a stalled/hung
887 system.
888
889 Currently, the only fixup is for the Geode machines using
5e3a77e9 890 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
891
892 Say Y if you want to enable the fixup. Currently, it's safe to
893 enable this option even if you don't need it.
894 Say N otherwise.
895
896config MICROCODE
8d86f390 897 tristate "/dev/cpu/microcode - microcode support"
506f1d07
SR
898 select FW_LOADER
899 ---help---
900 If you say Y here, you will be able to update the microcode on
80cc9f10
PO
901 certain Intel and AMD processors. The Intel support is for the
902 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
903 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
904 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
905 You will obviously need the actual microcode binary data itself
906 which is not shipped with the Linux kernel.
506f1d07 907
8d86f390
PO
908 This option selects the general module only, you need to select
909 at least one vendor specific module as well.
506f1d07
SR
910
911 To compile this driver as a module, choose M here: the
912 module will be called microcode.
913
8d86f390 914config MICROCODE_INTEL
8f9ca475
IM
915 bool "Intel microcode patch loading support"
916 depends on MICROCODE
917 default MICROCODE
918 select FW_LOADER
919 ---help---
920 This options enables microcode patch loading support for Intel
921 processors.
922
923 For latest news and information on obtaining all the required
924 Intel ingredients for this driver, check:
925 <http://www.urbanmyth.org/microcode/>.
8d86f390 926
80cc9f10 927config MICROCODE_AMD
8f9ca475
IM
928 bool "AMD microcode patch loading support"
929 depends on MICROCODE
930 select FW_LOADER
931 ---help---
932 If you select this option, microcode patch loading support for AMD
933 processors will be enabled.
80cc9f10 934
8f9ca475 935config MICROCODE_OLD_INTERFACE
3c2362e6 936 def_bool y
506f1d07 937 depends on MICROCODE
506f1d07
SR
938
939config X86_MSR
940 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 941 ---help---
506f1d07
SR
942 This device gives privileged processes access to the x86
943 Model-Specific Registers (MSRs). It is a character device with
944 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
945 MSR accesses are directed to a specific CPU on multi-processor
946 systems.
947
948config X86_CPUID
949 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 950 ---help---
506f1d07
SR
951 This device gives processes access to the x86 CPUID instruction to
952 be executed on a specific processor. It is a character device
953 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
954 /dev/cpu/31/cpuid.
955
9b779edf
JSR
956config X86_CPU_DEBUG
957 tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
958 ---help---
959 If you select this option, this will provide various x86 CPUs
960 information through debugfs.
961
506f1d07
SR
962choice
963 prompt "High Memory Support"
964 default HIGHMEM4G if !X86_NUMAQ
965 default HIGHMEM64G if X86_NUMAQ
966 depends on X86_32
967
968config NOHIGHMEM
969 bool "off"
970 depends on !X86_NUMAQ
971 ---help---
972 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
973 However, the address space of 32-bit x86 processors is only 4
974 Gigabytes large. That means that, if you have a large amount of
975 physical memory, not all of it can be "permanently mapped" by the
976 kernel. The physical memory that's not permanently mapped is called
977 "high memory".
978
979 If you are compiling a kernel which will never run on a machine with
980 more than 1 Gigabyte total physical RAM, answer "off" here (default
981 choice and suitable for most users). This will result in a "3GB/1GB"
982 split: 3GB are mapped so that each process sees a 3GB virtual memory
983 space and the remaining part of the 4GB virtual memory space is used
984 by the kernel to permanently map as much physical memory as
985 possible.
986
987 If the machine has between 1 and 4 Gigabytes physical RAM, then
988 answer "4GB" here.
989
990 If more than 4 Gigabytes is used then answer "64GB" here. This
991 selection turns Intel PAE (Physical Address Extension) mode on.
992 PAE implements 3-level paging on IA32 processors. PAE is fully
993 supported by Linux, PAE mode is implemented on all recent Intel
994 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
995 then the kernel will not boot on CPUs that don't support PAE!
996
997 The actual amount of total physical memory will either be
998 auto detected or can be forced by using a kernel command line option
999 such as "mem=256M". (Try "man bootparam" or see the documentation of
1000 your boot loader (lilo or loadlin) about how to pass options to the
1001 kernel at boot time.)
1002
1003 If unsure, say "off".
1004
1005config HIGHMEM4G
1006 bool "4GB"
1007 depends on !X86_NUMAQ
8f9ca475 1008 ---help---
506f1d07
SR
1009 Select this if you have a 32-bit processor and between 1 and 4
1010 gigabytes of physical RAM.
1011
1012config HIGHMEM64G
1013 bool "64GB"
1014 depends on !M386 && !M486
1015 select X86_PAE
8f9ca475 1016 ---help---
506f1d07
SR
1017 Select this if you have a 32-bit processor and more than 4
1018 gigabytes of physical RAM.
1019
1020endchoice
1021
1022choice
1023 depends on EXPERIMENTAL
1024 prompt "Memory split" if EMBEDDED
1025 default VMSPLIT_3G
1026 depends on X86_32
8f9ca475 1027 ---help---
506f1d07
SR
1028 Select the desired split between kernel and user memory.
1029
1030 If the address range available to the kernel is less than the
1031 physical memory installed, the remaining memory will be available
1032 as "high memory". Accessing high memory is a little more costly
1033 than low memory, as it needs to be mapped into the kernel first.
1034 Note that increasing the kernel address space limits the range
1035 available to user programs, making the address space there
1036 tighter. Selecting anything other than the default 3G/1G split
1037 will also likely make your kernel incompatible with binary-only
1038 kernel modules.
1039
1040 If you are not absolutely sure what you are doing, leave this
1041 option alone!
1042
1043 config VMSPLIT_3G
1044 bool "3G/1G user/kernel split"
1045 config VMSPLIT_3G_OPT
1046 depends on !X86_PAE
1047 bool "3G/1G user/kernel split (for full 1G low memory)"
1048 config VMSPLIT_2G
1049 bool "2G/2G user/kernel split"
1050 config VMSPLIT_2G_OPT
1051 depends on !X86_PAE
1052 bool "2G/2G user/kernel split (for full 2G low memory)"
1053 config VMSPLIT_1G
1054 bool "1G/3G user/kernel split"
1055endchoice
1056
1057config PAGE_OFFSET
1058 hex
1059 default 0xB0000000 if VMSPLIT_3G_OPT
1060 default 0x80000000 if VMSPLIT_2G
1061 default 0x78000000 if VMSPLIT_2G_OPT
1062 default 0x40000000 if VMSPLIT_1G
1063 default 0xC0000000
1064 depends on X86_32
1065
1066config HIGHMEM
3c2362e6 1067 def_bool y
506f1d07 1068 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1069
1070config X86_PAE
9ba16087 1071 bool "PAE (Physical Address Extension) Support"
506f1d07 1072 depends on X86_32 && !HIGHMEM4G
8f9ca475 1073 ---help---
506f1d07
SR
1074 PAE is required for NX support, and furthermore enables
1075 larger swapspace support for non-overcommit purposes. It
1076 has the cost of more pagetable lookup overhead, and also
1077 consumes more pagetable space per process.
1078
600715dc 1079config ARCH_PHYS_ADDR_T_64BIT
8f9ca475 1080 def_bool X86_64 || X86_PAE
600715dc 1081
9e899816
NP
1082config DIRECT_GBPAGES
1083 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1084 default y
1085 depends on X86_64
8f9ca475 1086 ---help---
9e899816
NP
1087 Allow the kernel linear mapping to use 1GB pages on CPUs that
1088 support it. This can improve the kernel's performance a tiny bit by
1089 reducing TLB pressure. If in doubt, say "Y".
1090
506f1d07
SR
1091# Common NUMA Features
1092config NUMA
fd51b2d7 1093 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1094 depends on SMP
604d2055 1095 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
0699eae1 1096 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
8f9ca475 1097 ---help---
506f1d07 1098 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1099
506f1d07
SR
1100 The kernel will try to allocate memory used by a CPU on the
1101 local memory controller of the CPU and add some more
1102 NUMA awareness to the kernel.
1103
c280ea5e 1104 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1105 (or later), AMD Opteron, or EM64T NUMA.
1106
1107 For 32-bit this is only needed on (rare) 32-bit-only platforms
1108 that support NUMA topologies, such as NUMAQ / Summit, or if you
1109 boot a 32-bit kernel on a 64-bit NUMA platform.
1110
1111 Otherwise, you should say N.
506f1d07
SR
1112
1113comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1114 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1115
1116config K8_NUMA
3c2362e6
HH
1117 def_bool y
1118 prompt "Old style AMD Opteron NUMA detection"
1119 depends on X86_64 && NUMA && PCI
8f9ca475
IM
1120 ---help---
1121 Enable K8 NUMA node topology detection. You should say Y here if
1122 you have a multi processor AMD K8 system. This uses an old
1123 method to read the NUMA configuration directly from the builtin
1124 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1125 instead, which also takes priority if both are compiled in.
506f1d07
SR
1126
1127config X86_64_ACPI_NUMA
3c2362e6
HH
1128 def_bool y
1129 prompt "ACPI NUMA detection"
506f1d07
SR
1130 depends on X86_64 && NUMA && ACPI && PCI
1131 select ACPI_NUMA
8f9ca475 1132 ---help---
506f1d07
SR
1133 Enable ACPI SRAT based node topology detection.
1134
6ec6e0d9
SS
1135# Some NUMA nodes have memory ranges that span
1136# other nodes. Even though a pfn is valid and
1137# between a node's start and end pfns, it may not
1138# reside on that node. See memmap_init_zone()
1139# for details.
1140config NODES_SPAN_OTHER_NODES
1141 def_bool y
1142 depends on X86_64_ACPI_NUMA
1143
506f1d07
SR
1144config NUMA_EMU
1145 bool "NUMA emulation"
1146 depends on X86_64 && NUMA
8f9ca475 1147 ---help---
506f1d07
SR
1148 Enable NUMA emulation. A flat machine will be split
1149 into virtual nodes when booted with "numa=fake=N", where N is the
1150 number of nodes. This is only useful for debugging.
1151
1152config NODES_SHIFT
d25e26b6 1153 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
46d50c98 1154 range 1 9
d25e26b6 1155 default "9" if MAXSMP
506f1d07
SR
1156 default "6" if X86_64
1157 default "4" if X86_NUMAQ
1158 default "3"
1159 depends on NEED_MULTIPLE_NODES
8f9ca475 1160 ---help---
1184dc2f 1161 Specify the maximum number of NUMA Nodes available on the target
692105b8 1162 system. Increases memory reserved to accommodate various tables.
506f1d07 1163
c1329375 1164config HAVE_ARCH_BOOTMEM
3c2362e6 1165 def_bool y
506f1d07 1166 depends on X86_32 && NUMA
506f1d07
SR
1167
1168config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1169 def_bool y
506f1d07 1170 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1171
1172config NEED_NODE_MEMMAP_SIZE
3c2362e6 1173 def_bool y
506f1d07 1174 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07
SR
1175
1176config HAVE_ARCH_ALLOC_REMAP
3c2362e6 1177 def_bool y
506f1d07 1178 depends on X86_32 && NUMA
506f1d07
SR
1179
1180config ARCH_FLATMEM_ENABLE
1181 def_bool y
99809963 1182 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
506f1d07
SR
1183
1184config ARCH_DISCONTIGMEM_ENABLE
1185 def_bool y
b263295d 1186 depends on NUMA && X86_32
506f1d07
SR
1187
1188config ARCH_DISCONTIGMEM_DEFAULT
1189 def_bool y
b263295d
CL
1190 depends on NUMA && X86_32
1191
1192config ARCH_SPARSEMEM_DEFAULT
1193 def_bool y
1194 depends on X86_64
506f1d07
SR
1195
1196config ARCH_SPARSEMEM_ENABLE
1197 def_bool y
4272ebfb 1198 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
506f1d07
SR
1199 select SPARSEMEM_STATIC if X86_32
1200 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1201
1202config ARCH_SELECT_MEMORY_MODEL
1203 def_bool y
b263295d 1204 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1205
1206config ARCH_MEMORY_PROBE
1207 def_bool X86_64
1208 depends on MEMORY_HOTPLUG
1209
1210source "mm/Kconfig"
1211
1212config HIGHPTE
1213 bool "Allocate 3rd-level pagetables from highmem"
1214 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
8f9ca475 1215 ---help---
506f1d07
SR
1216 The VM uses one page table entry for each page of physical memory.
1217 For systems with a lot of RAM, this can be wasteful of precious
1218 low memory. Setting this option will put user-space page table
1219 entries in high memory.
1220
9f077871 1221config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1222 bool "Check for low memory corruption"
1223 ---help---
1224 Periodically check for memory corruption in low memory, which
1225 is suspected to be caused by BIOS. Even when enabled in the
1226 configuration, it is disabled at runtime. Enable it by
1227 setting "memory_corruption_check=1" on the kernel command
1228 line. By default it scans the low 64k of memory every 60
1229 seconds; see the memory_corruption_check_size and
1230 memory_corruption_check_period parameters in
1231 Documentation/kernel-parameters.txt to adjust this.
1232
1233 When enabled with the default parameters, this option has
1234 almost no overhead, as it reserves a relatively small amount
1235 of memory and scans it infrequently. It both detects corruption
1236 and prevents it from affecting the running system.
1237
1238 It is, however, intended as a diagnostic tool; if repeatable
1239 BIOS-originated corruption always affects the same memory,
1240 you can use memmap= to prevent the kernel from using that
1241 memory.
9f077871 1242
c885df50 1243config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1244 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1245 depends on X86_CHECK_BIOS_CORRUPTION
1246 default y
8f9ca475
IM
1247 ---help---
1248 Set whether the default state of memory_corruption_check is
1249 on or off.
c885df50 1250
fc381519 1251config X86_RESERVE_LOW_64K
8f9ca475 1252 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
fc381519 1253 default y
8f9ca475
IM
1254 ---help---
1255 Reserve the first 64K of physical RAM on BIOSes that are known
1256 to potentially corrupt that memory range. A numbers of BIOSes are
1257 known to utilize this area during suspend/resume, so it must not
1258 be used by the kernel.
fc381519 1259
8f9ca475
IM
1260 Set this to N if you are absolutely sure that you trust the BIOS
1261 to get all its memory reservations and usages right.
fc381519 1262
8f9ca475
IM
1263 If you have doubts about the BIOS (e.g. suspend/resume does not
1264 work or there's kernel crashes after certain hardware hotplug
1265 events) and it's not AMI or Phoenix, then you might want to enable
1266 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1267 corruption patterns.
fc381519 1268
8f9ca475 1269 Say Y if unsure.
fc381519 1270
506f1d07
SR
1271config MATH_EMULATION
1272 bool
1273 prompt "Math emulation" if X86_32
1274 ---help---
1275 Linux can emulate a math coprocessor (used for floating point
1276 operations) if you don't have one. 486DX and Pentium processors have
1277 a math coprocessor built in, 486SX and 386 do not, unless you added
1278 a 487DX or 387, respectively. (The messages during boot time can
1279 give you some hints here ["man dmesg"].) Everyone needs either a
1280 coprocessor or this emulation.
1281
1282 If you don't have a math coprocessor, you need to say Y here; if you
1283 say Y here even though you have a coprocessor, the coprocessor will
1284 be used nevertheless. (This behavior can be changed with the kernel
1285 command line option "no387", which comes handy if your coprocessor
1286 is broken. Try "man bootparam" or see the documentation of your boot
1287 loader (lilo or loadlin) about how to pass options to the kernel at
1288 boot time.) This means that it is a good idea to say Y here if you
1289 intend to use this kernel on different machines.
1290
1291 More information about the internals of the Linux math coprocessor
1292 emulation can be found in <file:arch/x86/math-emu/README>.
1293
1294 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1295 kernel, it won't hurt.
1296
1297config MTRR
1298 bool "MTRR (Memory Type Range Register) support"
1299 ---help---
1300 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1301 the Memory Type Range Registers (MTRRs) may be used to control
1302 processor access to memory ranges. This is most useful if you have
1303 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1304 allows bus write transfers to be combined into a larger transfer
1305 before bursting over the PCI/AGP bus. This can increase performance
1306 of image write operations 2.5 times or more. Saying Y here creates a
1307 /proc/mtrr file which may be used to manipulate your processor's
1308 MTRRs. Typically the X server should use this.
1309
1310 This code has a reasonably generic interface so that similar
1311 control registers on other processors can be easily supported
1312 as well:
1313
1314 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1315 Registers (ARRs) which provide a similar functionality to MTRRs. For
1316 these, the ARRs are used to emulate the MTRRs.
1317 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1318 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1319 write-combining. All of these processors are supported by this code
1320 and it makes sense to say Y here if you have one of them.
1321
1322 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1323 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1324 can lead to all sorts of problems, so it's good to say Y here.
1325
1326 You can safely say Y even if your machine doesn't have MTRRs, you'll
1327 just add about 9 KB to your kernel.
1328
7225e751 1329 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1330
95ffa243 1331config MTRR_SANITIZER
2ffb3501 1332 def_bool y
95ffa243
YL
1333 prompt "MTRR cleanup support"
1334 depends on MTRR
8f9ca475 1335 ---help---
aba3728c
TG
1336 Convert MTRR layout from continuous to discrete, so X drivers can
1337 add writeback entries.
95ffa243 1338
aba3728c 1339 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1340 The largest mtrr entry size for a continuous block can be set with
aba3728c 1341 mtrr_chunk_size.
95ffa243 1342
2ffb3501 1343 If unsure, say Y.
95ffa243
YL
1344
1345config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1346 int "MTRR cleanup enable value (0-1)"
1347 range 0 1
1348 default "0"
95ffa243 1349 depends on MTRR_SANITIZER
8f9ca475 1350 ---help---
f5098d62 1351 Enable mtrr cleanup default value
95ffa243 1352
12031a62
YL
1353config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1354 int "MTRR cleanup spare reg num (0-7)"
1355 range 0 7
1356 default "1"
1357 depends on MTRR_SANITIZER
8f9ca475 1358 ---help---
12031a62 1359 mtrr cleanup spare entries default, it can be changed via
aba3728c 1360 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1361
2e5d9c85 1362config X86_PAT
2a8a2719 1363 bool
2e5d9c85 1364 prompt "x86 PAT support"
2a8a2719 1365 depends on MTRR
8f9ca475 1366 ---help---
2e5d9c85 1367 Use PAT attributes to setup page level cache control.
042b78e4 1368
2e5d9c85 1369 PATs are the modern equivalents of MTRRs and are much more
1370 flexible than MTRRs.
1371
1372 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1373 spontaneous reboots) or a non-working video driver.
2e5d9c85 1374
1375 If unsure, say Y.
1376
506f1d07 1377config EFI
9ba16087 1378 bool "EFI runtime service support"
5b83683f 1379 depends on ACPI
506f1d07 1380 ---help---
8f9ca475
IM
1381 This enables the kernel to use EFI runtime services that are
1382 available (such as the EFI variable services).
506f1d07 1383
8f9ca475
IM
1384 This option is only useful on systems that have EFI firmware.
1385 In addition, you should use the latest ELILO loader available
1386 at <http://elilo.sourceforge.net> in order to take advantage
1387 of EFI runtime services. However, even with this option, the
1388 resultant kernel should continue to boot on existing non-EFI
1389 platforms.
506f1d07 1390
506f1d07 1391config SECCOMP
3c2362e6
HH
1392 def_bool y
1393 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1394 ---help---
506f1d07
SR
1395 This kernel feature is useful for number crunching applications
1396 that may need to compute untrusted bytecode during their
1397 execution. By using pipes or other transports made available to
1398 the process as file descriptors supporting the read/write
1399 syscalls, it's possible to isolate those applications in
1400 their own address space using seccomp. Once seccomp is
9c0bbee8 1401 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1402 and the task is only allowed to execute a few safe syscalls
1403 defined by each seccomp mode.
1404
1405 If unsure, say Y. Only embedded should say N here.
1406
113c5413
IM
1407config CC_STACKPROTECTOR_ALL
1408 bool
1409
506f1d07
SR
1410config CC_STACKPROTECTOR
1411 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
113c5413 1412 select CC_STACKPROTECTOR_ALL
8f9ca475
IM
1413 ---help---
1414 This option turns on the -fstack-protector GCC feature. This
113c5413
IM
1415 feature puts, at the beginning of functions, a canary value on
1416 the stack just before the return address, and validates
506f1d07
SR
1417 the value just before actually returning. Stack based buffer
1418 overflows (that need to overwrite this return address) now also
1419 overwrite the canary, which gets detected and the attack is then
1420 neutralized via a kernel panic.
1421
1422 This feature requires gcc version 4.2 or above, or a distribution
1423 gcc with the feature backported. Older versions are automatically
113c5413
IM
1424 detected and for those versions, this configuration option is
1425 ignored. (and a warning is printed during bootup)
506f1d07
SR
1426
1427source kernel/Kconfig.hz
1428
1429config KEXEC
1430 bool "kexec system call"
8f9ca475 1431 ---help---
506f1d07
SR
1432 kexec is a system call that implements the ability to shutdown your
1433 current kernel, and to start another kernel. It is like a reboot
1434 but it is independent of the system firmware. And like a reboot
1435 you can start any kernel with it, not just Linux.
1436
1437 The name comes from the similarity to the exec system call.
1438
1439 It is an ongoing process to be certain the hardware in a machine
1440 is properly shutdown, so do not be surprised if this code does not
1441 initially work for you. It may help to enable device hotplugging
1442 support. As of this writing the exact hardware interface is
1443 strongly in flux, so no good recommendation can be made.
1444
1445config CRASH_DUMP
04b69447 1446 bool "kernel crash dumps"
506f1d07 1447 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1448 ---help---
506f1d07
SR
1449 Generate crash dump after being started by kexec.
1450 This should be normally only set in special crash dump kernels
1451 which are loaded in the main kernel with kexec-tools into
1452 a specially reserved region and then later executed after
1453 a crash by kdump/kexec. The crash dump kernel must be compiled
1454 to a memory address not used by the main kernel or BIOS using
1455 PHYSICAL_START, or it must be built as a relocatable image
1456 (CONFIG_RELOCATABLE=y).
1457 For more details see Documentation/kdump/kdump.txt
1458
3ab83521
HY
1459config KEXEC_JUMP
1460 bool "kexec jump (EXPERIMENTAL)"
1461 depends on EXPERIMENTAL
fee7b0d8 1462 depends on KEXEC && HIBERNATION
8f9ca475 1463 ---help---
89081d17
HY
1464 Jump between original kernel and kexeced kernel and invoke
1465 code in physical address mode via KEXEC
3ab83521 1466
506f1d07
SR
1467config PHYSICAL_START
1468 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
ceefccc9 1469 default "0x1000000"
8f9ca475 1470 ---help---
506f1d07
SR
1471 This gives the physical address where the kernel is loaded.
1472
1473 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1474 bzImage will decompress itself to above physical address and
1475 run from there. Otherwise, bzImage will run from the address where
1476 it has been loaded by the boot loader and will ignore above physical
1477 address.
1478
1479 In normal kdump cases one does not have to set/change this option
1480 as now bzImage can be compiled as a completely relocatable image
1481 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1482 address. This option is mainly useful for the folks who don't want
1483 to use a bzImage for capturing the crash dump and want to use a
1484 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1485 to be specifically compiled to run from a specific memory area
1486 (normally a reserved region) and this option comes handy.
1487
ceefccc9
PA
1488 So if you are using bzImage for capturing the crash dump,
1489 leave the value here unchanged to 0x1000000 and set
1490 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1491 for capturing the crash dump change this value to start of
1492 the reserved region. In other words, it can be set based on
1493 the "X" value as specified in the "crashkernel=YM@XM"
1494 command line boot parameter passed to the panic-ed
1495 kernel. Please take a look at Documentation/kdump/kdump.txt
1496 for more details about crash dumps.
506f1d07
SR
1497
1498 Usage of bzImage for capturing the crash dump is recommended as
1499 one does not have to build two kernels. Same kernel can be used
1500 as production kernel and capture kernel. Above option should have
1501 gone away after relocatable bzImage support is introduced. But it
1502 is present because there are users out there who continue to use
1503 vmlinux for dump capture. This option should go away down the
1504 line.
1505
1506 Don't change this unless you know what you are doing.
1507
1508config RELOCATABLE
26717808
PA
1509 bool "Build a relocatable kernel"
1510 default y
8f9ca475 1511 ---help---
506f1d07
SR
1512 This builds a kernel image that retains relocation information
1513 so it can be loaded someplace besides the default 1MB.
1514 The relocations tend to make the kernel binary about 10% larger,
1515 but are discarded at runtime.
1516
1517 One use is for the kexec on panic case where the recovery kernel
1518 must live at a different physical address than the primary
1519 kernel.
1520
1521 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1522 it has been loaded at and the compile time physical address
1523 (CONFIG_PHYSICAL_START) is ignored.
1524
845adf72
PA
1525# Relocation on x86-32 needs some additional build support
1526config X86_NEED_RELOCS
1527 def_bool y
1528 depends on X86_32 && RELOCATABLE
1529
506f1d07
SR
1530config PHYSICAL_ALIGN
1531 hex
1532 prompt "Alignment value to which kernel should be aligned" if X86_32
ceefccc9
PA
1533 default "0x1000000"
1534 range 0x2000 0x1000000
8f9ca475 1535 ---help---
506f1d07
SR
1536 This value puts the alignment restrictions on physical address
1537 where kernel is loaded and run from. Kernel is compiled for an
1538 address which meets above alignment restriction.
1539
1540 If bootloader loads the kernel at a non-aligned address and
1541 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1542 address aligned to above value and run from there.
1543
1544 If bootloader loads the kernel at a non-aligned address and
1545 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1546 load address and decompress itself to the address it has been
1547 compiled for and run from there. The address for which kernel is
1548 compiled already meets above alignment restrictions. Hence the
1549 end result is that kernel runs from a physical address meeting
1550 above alignment restrictions.
1551
1552 Don't change this unless you know what you are doing.
1553
1554config HOTPLUG_CPU
7c13e6a3 1555 bool "Support for hot-pluggable CPUs"
4b19ed91 1556 depends on SMP && HOTPLUG
506f1d07 1557 ---help---
7c13e6a3
DS
1558 Say Y here to allow turning CPUs off and on. CPUs can be
1559 controlled through /sys/devices/system/cpu.
1560 ( Note: power management support will enable this option
1561 automatically on SMP systems. )
1562 Say N if you want to disable CPU hotplug.
506f1d07
SR
1563
1564config COMPAT_VDSO
3c2362e6
HH
1565 def_bool y
1566 prompt "Compat VDSO support"
af65d648 1567 depends on X86_32 || IA32_EMULATION
8f9ca475 1568 ---help---
af65d648 1569 Map the 32-bit VDSO to the predictable old-style address too.
506f1d07
SR
1570 ---help---
1571 Say N here if you are running a sufficiently recent glibc
1572 version (2.3.3 or later), to remove the high-mapped
1573 VDSO mapping and to exclusively use the randomized VDSO.
1574
1575 If unsure, say Y.
1576
516cbf37
TB
1577config CMDLINE_BOOL
1578 bool "Built-in kernel command line"
1579 default n
8f9ca475 1580 ---help---
516cbf37
TB
1581 Allow for specifying boot arguments to the kernel at
1582 build time. On some systems (e.g. embedded ones), it is
1583 necessary or convenient to provide some or all of the
1584 kernel boot arguments with the kernel itself (that is,
1585 to not rely on the boot loader to provide them.)
1586
1587 To compile command line arguments into the kernel,
1588 set this option to 'Y', then fill in the
1589 the boot arguments in CONFIG_CMDLINE.
1590
1591 Systems with fully functional boot loaders (i.e. non-embedded)
1592 should leave this option set to 'N'.
1593
1594config CMDLINE
1595 string "Built-in kernel command string"
1596 depends on CMDLINE_BOOL
1597 default ""
8f9ca475 1598 ---help---
516cbf37
TB
1599 Enter arguments here that should be compiled into the kernel
1600 image and used at boot time. If the boot loader provides a
1601 command line at boot time, it is appended to this string to
1602 form the full kernel command line, when the system boots.
1603
1604 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1605 change this behavior.
1606
1607 In most cases, the command line (whether built-in or provided
1608 by the boot loader) should specify the device for the root
1609 file system.
1610
1611config CMDLINE_OVERRIDE
1612 bool "Built-in command line overrides boot loader arguments"
1613 default n
1614 depends on CMDLINE_BOOL
8f9ca475 1615 ---help---
516cbf37
TB
1616 Set this option to 'Y' to have the kernel ignore the boot loader
1617 command line, and use ONLY the built-in command line.
1618
1619 This is used to work around broken boot loaders. This should
1620 be set to 'N' under normal conditions.
1621
506f1d07
SR
1622endmenu
1623
1624config ARCH_ENABLE_MEMORY_HOTPLUG
1625 def_bool y
1626 depends on X86_64 || (X86_32 && HIGHMEM)
1627
35551053
GH
1628config ARCH_ENABLE_MEMORY_HOTREMOVE
1629 def_bool y
1630 depends on MEMORY_HOTPLUG
1631
506f1d07
SR
1632config HAVE_ARCH_EARLY_PFN_TO_NID
1633 def_bool X86_64
1634 depends on NUMA
1635
da85f865 1636menu "Power management and ACPI options"
e279b6c1
SR
1637
1638config ARCH_HIBERNATION_HEADER
3c2362e6 1639 def_bool y
e279b6c1 1640 depends on X86_64 && HIBERNATION
e279b6c1
SR
1641
1642source "kernel/power/Kconfig"
1643
1644source "drivers/acpi/Kconfig"
1645
a6b68076
AK
1646config X86_APM_BOOT
1647 bool
1648 default y
1649 depends on APM || APM_MODULE
1650
e279b6c1
SR
1651menuconfig APM
1652 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 1653 depends on X86_32 && PM_SLEEP
e279b6c1
SR
1654 ---help---
1655 APM is a BIOS specification for saving power using several different
1656 techniques. This is mostly useful for battery powered laptops with
1657 APM compliant BIOSes. If you say Y here, the system time will be
1658 reset after a RESUME operation, the /proc/apm device will provide
1659 battery status information, and user-space programs will receive
1660 notification of APM "events" (e.g. battery status change).
1661
1662 If you select "Y" here, you can disable actual use of the APM
1663 BIOS by passing the "apm=off" option to the kernel at boot time.
1664
1665 Note that the APM support is almost completely disabled for
1666 machines with more than one CPU.
1667
1668 In order to use APM, you will need supporting software. For location
53471121 1669 and more information, read <file:Documentation/power/pm.txt> and the
e279b6c1
SR
1670 Battery Powered Linux mini-HOWTO, available from
1671 <http://www.tldp.org/docs.html#howto>.
1672
1673 This driver does not spin down disk drives (see the hdparm(8)
1674 manpage ("man 8 hdparm") for that), and it doesn't turn off
1675 VESA-compliant "green" monitors.
1676
1677 This driver does not support the TI 4000M TravelMate and the ACER
1678 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1679 desktop machines also don't have compliant BIOSes, and this driver
1680 may cause those machines to panic during the boot phase.
1681
1682 Generally, if you don't have a battery in your machine, there isn't
1683 much point in using this driver and you should say N. If you get
1684 random kernel OOPSes or reboots that don't seem to be related to
1685 anything, try disabling/enabling this option (or disabling/enabling
1686 APM in your BIOS).
1687
1688 Some other things you should try when experiencing seemingly random,
1689 "weird" problems:
1690
1691 1) make sure that you have enough swap space and that it is
1692 enabled.
1693 2) pass the "no-hlt" option to the kernel
1694 3) switch on floating point emulation in the kernel and pass
1695 the "no387" option to the kernel
1696 4) pass the "floppy=nodma" option to the kernel
1697 5) pass the "mem=4M" option to the kernel (thereby disabling
1698 all but the first 4 MB of RAM)
1699 6) make sure that the CPU is not over clocked.
1700 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1701 8) disable the cache from your BIOS settings
1702 9) install a fan for the video card or exchange video RAM
1703 10) install a better fan for the CPU
1704 11) exchange RAM chips
1705 12) exchange the motherboard.
1706
1707 To compile this driver as a module, choose M here: the
1708 module will be called apm.
1709
1710if APM
1711
1712config APM_IGNORE_USER_SUSPEND
1713 bool "Ignore USER SUSPEND"
8f9ca475 1714 ---help---
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1715 This option will ignore USER SUSPEND requests. On machines with a
1716 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1717 series notebooks, it is necessary to say Y because of a BIOS bug.
1718
1719config APM_DO_ENABLE
1720 bool "Enable PM at boot time"
1721 ---help---
1722 Enable APM features at boot time. From page 36 of the APM BIOS
1723 specification: "When disabled, the APM BIOS does not automatically
1724 power manage devices, enter the Standby State, enter the Suspend
1725 State, or take power saving steps in response to CPU Idle calls."
1726 This driver will make CPU Idle calls when Linux is idle (unless this
1727 feature is turned off -- see "Do CPU IDLE calls", below). This
1728 should always save battery power, but more complicated APM features
1729 will be dependent on your BIOS implementation. You may need to turn
1730 this option off if your computer hangs at boot time when using APM
1731 support, or if it beeps continuously instead of suspending. Turn
1732 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1733 T400CDT. This is off by default since most machines do fine without
1734 this feature.
1735
1736config APM_CPU_IDLE
1737 bool "Make CPU Idle calls when idle"
8f9ca475 1738 ---help---
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SR
1739 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1740 On some machines, this can activate improved power savings, such as
1741 a slowed CPU clock rate, when the machine is idle. These idle calls
1742 are made after the idle loop has run for some length of time (e.g.,
1743 333 mS). On some machines, this will cause a hang at boot time or
1744 whenever the CPU becomes idle. (On machines with more than one CPU,
1745 this option does nothing.)
1746
1747config APM_DISPLAY_BLANK
1748 bool "Enable console blanking using APM"
8f9ca475 1749 ---help---
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1750 Enable console blanking using the APM. Some laptops can use this to
1751 turn off the LCD backlight when the screen blanker of the Linux
1752 virtual console blanks the screen. Note that this is only used by
1753 the virtual console screen blanker, and won't turn off the backlight
1754 when using the X Window system. This also doesn't have anything to
1755 do with your VESA-compliant power-saving monitor. Further, this
1756 option doesn't work for all laptops -- it might not turn off your
1757 backlight at all, or it might print a lot of errors to the console,
1758 especially if you are using gpm.
1759
1760config APM_ALLOW_INTS
1761 bool "Allow interrupts during APM BIOS calls"
8f9ca475 1762 ---help---
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1763 Normally we disable external interrupts while we are making calls to
1764 the APM BIOS as a measure to lessen the effects of a badly behaving
1765 BIOS implementation. The BIOS should reenable interrupts if it
1766 needs to. Unfortunately, some BIOSes do not -- especially those in
1767 many of the newer IBM Thinkpads. If you experience hangs when you
1768 suspend, try setting this to Y. Otherwise, say N.
1769
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1770endif # APM
1771
1772source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1773
1774source "drivers/cpuidle/Kconfig"
1775
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1776source "drivers/idle/Kconfig"
1777
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1778endmenu
1779
1780
1781menu "Bus options (PCI etc.)"
1782
1783config PCI
1ac97018 1784 bool "PCI support"
1c858087 1785 default y
e279b6c1 1786 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
8f9ca475 1787 ---help---
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1788 Find out whether you have a PCI motherboard. PCI is the name of a
1789 bus system, i.e. the way the CPU talks to the other stuff inside
1790 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1791 VESA. If you have PCI, say Y, otherwise N.
1792
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1793choice
1794 prompt "PCI access mode"
efefa6f6 1795 depends on X86_32 && PCI
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1796 default PCI_GOANY
1797 ---help---
1798 On PCI systems, the BIOS can be used to detect the PCI devices and
1799 determine their configuration. However, some old PCI motherboards
1800 have BIOS bugs and may crash if this is done. Also, some embedded
1801 PCI-based systems don't have any BIOS at all. Linux can also try to
1802 detect the PCI hardware directly without using the BIOS.
1803
1804 With this option, you can specify how Linux should detect the
1805 PCI devices. If you choose "BIOS", the BIOS will be used,
1806 if you choose "Direct", the BIOS won't be used, and if you
1807 choose "MMConfig", then PCI Express MMCONFIG will be used.
1808 If you choose "Any", the kernel will try MMCONFIG, then the
1809 direct access method and falls back to the BIOS if that doesn't
1810 work. If unsure, go with the default, which is "Any".
1811
1812config PCI_GOBIOS
1813 bool "BIOS"
1814
1815config PCI_GOMMCONFIG
1816 bool "MMConfig"
1817
1818config PCI_GODIRECT
1819 bool "Direct"
1820
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1821config PCI_GOOLPC
1822 bool "OLPC"
1823 depends on OLPC
1824
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1825config PCI_GOANY
1826 bool "Any"
1827
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SR
1828endchoice
1829
1830config PCI_BIOS
3c2362e6 1831 def_bool y
efefa6f6 1832 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
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1833
1834# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1835config PCI_DIRECT
3c2362e6 1836 def_bool y
efefa6f6 1837 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
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1838
1839config PCI_MMCONFIG
3c2362e6 1840 def_bool y
e279b6c1 1841 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 1842
3ef0e1f8 1843config PCI_OLPC
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AS
1844 def_bool y
1845 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 1846
e279b6c1 1847config PCI_DOMAINS
3c2362e6 1848 def_bool y
e279b6c1 1849 depends on PCI
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1850
1851config PCI_MMCONFIG
1852 bool "Support mmconfig PCI config space access"
1853 depends on X86_64 && PCI && ACPI
1854
1855config DMAR
1856 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
4cf2e75d 1857 depends on PCI_MSI && ACPI && EXPERIMENTAL
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1858 help
1859 DMA remapping (DMAR) devices support enables independent address
1860 translations for Direct Memory Access (DMA) from devices.
1861 These DMA remapping devices are reported via ACPI tables
1862 and include PCI device scope covered by these DMA
1863 remapping devices.
1864
0cd5c3c8 1865config DMAR_DEFAULT_ON
f6be37fd 1866 def_bool y
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KM
1867 prompt "Enable DMA Remapping Devices by default"
1868 depends on DMAR
1869 help
1870 Selecting this option will enable a DMAR device at boot time if
1871 one is found. If this option is not selected, DMAR support can
1872 be enabled by passing intel_iommu=on to the kernel. It is
1873 recommended you say N here while the DMAR code remains
1874 experimental.
1875
e279b6c1 1876config DMAR_GFX_WA
3c2362e6
HH
1877 def_bool y
1878 prompt "Support for Graphics workaround"
e279b6c1 1879 depends on DMAR
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1880 ---help---
1881 Current Graphics drivers tend to use physical address
1882 for DMA and avoid using DMA APIs. Setting this config
1883 option permits the IOMMU driver to set a unity map for
1884 all the OS-visible memory. Hence the driver can continue
1885 to use physical addresses for DMA.
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1886
1887config DMAR_FLOPPY_WA
3c2362e6 1888 def_bool y
e279b6c1 1889 depends on DMAR
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1890 ---help---
1891 Floppy disk drivers are know to bypass DMA API calls
1892 thereby failing to work when IOMMU is enabled. This
1893 workaround will setup a 1:1 mapping for the first
1894 16M to make floppy (an ISA device) work.
e279b6c1 1895
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SS
1896config INTR_REMAP
1897 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1898 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
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1899 ---help---
1900 Supports Interrupt remapping for IO-APIC and MSI devices.
1901 To use x2apic mode in the CPU's which support x2APIC enhancements or
1902 to support platforms with CPU's having > 8 bit APIC ID, say Y.
9fa8c481 1903
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1904source "drivers/pci/pcie/Kconfig"
1905
1906source "drivers/pci/Kconfig"
1907
1908# x86_64 have no ISA slots, but do have ISA-style DMA.
1909config ISA_DMA_API
3c2362e6 1910 def_bool y
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1911
1912if X86_32
1913
1914config ISA
1915 bool "ISA support"
8f9ca475 1916 ---help---
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1917 Find out whether you have ISA slots on your motherboard. ISA is the
1918 name of a bus system, i.e. the way the CPU talks to the other stuff
1919 inside your box. Other bus systems are PCI, EISA, MicroChannel
1920 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1921 newer boards don't support it. If you have ISA, say Y, otherwise N.
1922
1923config EISA
1924 bool "EISA support"
1925 depends on ISA
1926 ---help---
1927 The Extended Industry Standard Architecture (EISA) bus was
1928 developed as an open alternative to the IBM MicroChannel bus.
1929
1930 The EISA bus provided some of the features of the IBM MicroChannel
1931 bus while maintaining backward compatibility with cards made for
1932 the older ISA bus. The EISA bus saw limited use between 1988 and
1933 1995 when it was made obsolete by the PCI bus.
1934
1935 Say Y here if you are building a kernel for an EISA-based machine.
1936
1937 Otherwise, say N.
1938
1939source "drivers/eisa/Kconfig"
1940
1941config MCA
72ee6ebb 1942 bool "MCA support"
8f9ca475 1943 ---help---
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1944 MicroChannel Architecture is found in some IBM PS/2 machines and
1945 laptops. It is a bus system similar to PCI or ISA. See
1946 <file:Documentation/mca.txt> (and especially the web page given
1947 there) before attempting to build an MCA bus kernel.
1948
1949source "drivers/mca/Kconfig"
1950
1951config SCx200
1952 tristate "NatSemi SCx200 support"
8f9ca475 1953 ---help---
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1954 This provides basic support for National Semiconductor's
1955 (now AMD's) Geode processors. The driver probes for the
1956 PCI-IDs of several on-chip devices, so its a good dependency
1957 for other scx200_* drivers.
1958
1959 If compiled as a module, the driver is named scx200.
1960
1961config SCx200HR_TIMER
1962 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1963 depends on SCx200 && GENERIC_TIME
1964 default y
8f9ca475 1965 ---help---
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SR
1966 This driver provides a clocksource built upon the on-chip
1967 27MHz high-resolution timer. Its also a workaround for
1968 NSC Geode SC-1100's buggy TSC, which loses time when the
1969 processor goes idle (as is done by the scheduler). The
1970 other workaround is idle=poll boot option.
1971
1972config GEODE_MFGPT_TIMER
3c2362e6
HH
1973 def_bool y
1974 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
e279b6c1 1975 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
8f9ca475 1976 ---help---
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SR
1977 This driver provides a clock event source based on the MFGPT
1978 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1979 MFGPTs have a better resolution and max interval than the
1980 generic PIT, and are suitable for use as high-res timers.
1981
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1982config OLPC
1983 bool "One Laptop Per Child support"
1984 default n
8f9ca475 1985 ---help---
3ef0e1f8
AS
1986 Add support for detecting the unique features of the OLPC
1987 XO hardware.
1988
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SR
1989endif # X86_32
1990
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1991config K8_NB
1992 def_bool y
bc0120fd 1993 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
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1994
1995source "drivers/pcmcia/Kconfig"
1996
1997source "drivers/pci/hotplug/Kconfig"
1998
1999endmenu
2000
2001
2002menu "Executable file formats / Emulations"
2003
2004source "fs/Kconfig.binfmt"
2005
2006config IA32_EMULATION
2007 bool "IA32 Emulation"
2008 depends on X86_64
a97f52e6 2009 select COMPAT_BINFMT_ELF
8f9ca475 2010 ---help---
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2011 Include code to run 32-bit programs under a 64-bit kernel. You should
2012 likely turn this on, unless you're 100% sure that you don't have any
2013 32-bit programs left.
2014
2015config IA32_AOUT
8f9ca475
IM
2016 tristate "IA32 a.out support"
2017 depends on IA32_EMULATION
2018 ---help---
2019 Support old a.out binaries in the 32bit emulation.
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SR
2020
2021config COMPAT
3c2362e6 2022 def_bool y
e279b6c1 2023 depends on IA32_EMULATION
e279b6c1
SR
2024
2025config COMPAT_FOR_U64_ALIGNMENT
2026 def_bool COMPAT
2027 depends on X86_64
2028
2029config SYSVIPC_COMPAT
3c2362e6 2030 def_bool y
b8992195 2031 depends on COMPAT && SYSVIPC
e279b6c1
SR
2032
2033endmenu
2034
2035
e5beae16
KP
2036config HAVE_ATOMIC_IOMAP
2037 def_bool y
2038 depends on X86_32
2039
e279b6c1
SR
2040source "net/Kconfig"
2041
2042source "drivers/Kconfig"
2043
2044source "drivers/firmware/Kconfig"
2045
2046source "fs/Kconfig"
2047
e279b6c1
SR
2048source "arch/x86/Kconfig.debug"
2049
2050source "security/Kconfig"
2051
2052source "crypto/Kconfig"
2053
edf88417
AK
2054source "arch/x86/kvm/Kconfig"
2055
e279b6c1 2056source "lib/Kconfig"