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1032c0ba 1# x86 configuration
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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"
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8 help
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
1a4e3f89 37 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
fcbc04c0 38 select HAVE_ARCH_KGDB if !X86_VOYAGER
99bbc4b1 39 select HAVE_ARCH_TRACEHOOK
323ec001 40 select HAVE_GENERIC_DMA_COHERENT if X86_32
58340a07 41 select HAVE_EFFICIENT_UNALIGNED_ACCESS
8d26487f 42 select USER_STACKTRACE_SUPPORT
7d8330a5 43
73531905 44config ARCH_DEFCONFIG
b9b39bfb 45 string
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46 default "arch/x86/configs/i386_defconfig" if X86_32
47 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 48
8d5fffb9 49config GENERIC_TIME
3c2362e6 50 def_bool y
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51
52config GENERIC_CMOS_UPDATE
3c2362e6 53 def_bool y
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54
55config CLOCKSOURCE_WATCHDOG
3c2362e6 56 def_bool y
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57
58config GENERIC_CLOCKEVENTS
3c2362e6 59 def_bool y
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60
61config GENERIC_CLOCKEVENTS_BROADCAST
3c2362e6 62 def_bool y
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63 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
64
65config LOCKDEP_SUPPORT
3c2362e6 66 def_bool y
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67
68config STACKTRACE_SUPPORT
3c2362e6 69 def_bool y
8d5fffb9 70
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71config HAVE_LATENCYTOP_SUPPORT
72 def_bool y
73
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74config FAST_CMPXCHG_LOCAL
75 bool
76 default y
77
8d5fffb9 78config MMU
3c2362e6 79 def_bool y
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80
81config ZONE_DMA
3c2362e6 82 def_bool y
8d5fffb9 83
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84config SBUS
85 bool
86
87config GENERIC_ISA_DMA
3c2362e6 88 def_bool y
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89
90config GENERIC_IOMAP
3c2362e6 91 def_bool y
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92
93config GENERIC_BUG
3c2362e6 94 def_bool y
8d5fffb9 95 depends on BUG
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96 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
97
98config GENERIC_BUG_RELATIVE_POINTERS
99 bool
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100
101config GENERIC_HWEIGHT
3c2362e6 102 def_bool y
8d5fffb9 103
a6082959 104config GENERIC_GPIO
9ba16087 105 bool
a6082959 106
8d5fffb9 107config ARCH_MAY_HAVE_PC_FDC
3c2362e6 108 def_bool y
8d5fffb9 109
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110config RWSEM_GENERIC_SPINLOCK
111 def_bool !X86_XADD
112
113config RWSEM_XCHGADD_ALGORITHM
114 def_bool X86_XADD
115
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116config ARCH_HAS_CPU_IDLE_WAIT
117 def_bool y
118
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119config GENERIC_CALIBRATE_DELAY
120 def_bool y
121
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122config GENERIC_TIME_VSYSCALL
123 bool
124 default X86_64
125
9a0b8415 126config ARCH_HAS_CPU_RELAX
127 def_bool y
128
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129config ARCH_HAS_DEFAULT_IDLE
130 def_bool y
131
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132config ARCH_HAS_CACHE_LINE_SIZE
133 def_bool y
134
dd5af90a 135config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 136 def_bool y
b32ef636 137
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138config HAVE_CPUMASK_OF_CPU_MAP
139 def_bool X86_64_SMP
140
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141config ARCH_HIBERNATION_POSSIBLE
142 def_bool y
143 depends on !SMP || !X86_VOYAGER
144
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145config ARCH_SUSPEND_POSSIBLE
146 def_bool y
147 depends on !X86_VOYAGER
148
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149config ZONE_DMA32
150 bool
151 default X86_64
152
153config ARCH_POPULATES_NODE_MAP
154 def_bool y
155
156config AUDIT_ARCH
157 bool
158 default X86_64
159
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160config ARCH_SUPPORTS_OPTIMIZED_INLINING
161 def_bool y
162
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163# Use the generic interrupt handling code in kernel/irq/:
164config GENERIC_HARDIRQS
165 bool
166 default y
167
168config GENERIC_IRQ_PROBE
169 bool
170 default y
171
172config GENERIC_PENDING_IRQ
173 bool
174 depends on GENERIC_HARDIRQS && SMP
175 default y
176
177config X86_SMP
178 bool
6b0c3d44 179 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
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180 default y
181
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182config USE_GENERIC_SMP_HELPERS
183 def_bool y
184 depends on SMP
185
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186config X86_32_SMP
187 def_bool y
188 depends on X86_32 && SMP
189
190config X86_64_SMP
191 def_bool y
192 depends on X86_64 && SMP
193
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194config X86_HT
195 bool
ee0011a7 196 depends on SMP
efefa6f6 197 depends on (X86_32 && !X86_VOYAGER) || X86_64
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198 default y
199
200config X86_BIOS_REBOOT
201 bool
31ac409a 202 depends on !X86_VOYAGER
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203 default y
204
205config X86_TRAMPOLINE
206 bool
e44b7b75 207 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
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208 default y
209
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210config X86_32_LAZY_GS
211 def_bool y
212 depends on X86_32
213
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214config KTIME_SCALAR
215 def_bool X86_32
506f1d07 216source "init/Kconfig"
dc52ddc0 217source "kernel/Kconfig.freezer"
8d5fffb9 218
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219menu "Processor type and features"
220
221source "kernel/time/Kconfig"
222
223config SMP
224 bool "Symmetric multi-processing support"
225 ---help---
226 This enables support for systems with more than one CPU. If you have
227 a system with only one CPU, like most personal computers, say N. If
228 you have a system with more than one CPU, say Y.
229
230 If you say N here, the kernel will run on single and multiprocessor
231 machines, but will use only one CPU of a multiprocessor machine. If
232 you say Y here, the kernel will run on many, but not all,
233 singleprocessor machines. On a singleprocessor machine, the kernel
234 will run faster if you say N here.
235
236 Note that if you say Y here and choose architecture "586" or
237 "Pentium" under "Processor family", the kernel will not work on 486
238 architectures. Similarly, multiprocessor kernels for the "PPro"
239 architecture may not work on all Pentium based boards.
240
241 People using multiprocessor machines who say Y here should also say
242 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
243 Management" code will be disabled if you say Y here.
244
03502faa 245 See also <file:Documentation/i386/IO-APIC.txt>,
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246 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
247 <http://www.tldp.org/docs.html#howto>.
248
249 If you don't know what to do here, say N.
250
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251config X86_HAS_BOOT_CPU_ID
252 def_bool y
253 depends on X86_VOYAGER
254
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255config SPARSE_IRQ
256 bool "Support sparse irq numbering"
17483a1f 257 depends on PCI_MSI || HT_IRQ
0b8f1efa 258 help
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259 This enables support for sparse irqs. This is useful for distro
260 kernels that want to define a high CONFIG_NR_CPUS value but still
261 want to have low kernel memory footprint on smaller machines.
0b8f1efa 262
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263 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
264 out the irq_desc[] array in a more NUMA-friendly way. )
265
266 If you don't know what to do here, say N.
0b8f1efa 267
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268config NUMA_MIGRATE_IRQ_DESC
269 bool "Move irq desc when changing irq smp_affinity"
b9098957 270 depends on SPARSE_IRQ && NUMA
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271 default n
272 help
273 This enables moving irq_desc to cpu/node that irq will use handled.
274
275 If you don't know what to do here, say N.
276
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277config X86_FIND_SMP_CONFIG
278 def_bool y
1b84e1c8 279 depends on X86_MPPARSE || X86_VOYAGER
6695c85b 280
6695c85b 281config X86_MPPARSE
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282 bool "Enable MPS table" if ACPI
283 default y
5ab74722 284 depends on X86_LOCAL_APIC
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285 help
286 For old smp systems that do not have proper acpi support. Newer systems
287 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 288
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289choice
290 prompt "Subarchitecture Type"
291 default X86_PC
292
293config X86_PC
294 bool "PC-compatible"
295 help
296 Choose this option if your computer is a standard PC or compatible.
297
298config X86_ELAN
299 bool "AMD Elan"
300 depends on X86_32
301 help
302 Select this for an AMD Elan processor.
303
304 Do not use this option for K6/Athlon/Opteron processors!
305
306 If unsure, choose "PC-compatible" instead.
307
308config X86_VOYAGER
309 bool "Voyager (NCR)"
1ac97018 310 depends on X86_32 && (SMP || BROKEN) && !PCI
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311 help
312 Voyager is an MCA-based 32-way capable SMP architecture proprietary
313 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
314
315 *** WARNING ***
316
317 If you do not specifically know you have a Voyager based machine,
318 say N here, otherwise the kernel you build will not be bootable.
319
506f1d07 320config X86_GENERICARCH
d49c4288 321 bool "Generic architecture"
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322 depends on X86_32
323 help
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324 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
325 subarchitectures. It is intended for a generic binary kernel.
326 if you select them all, kernel will probe it one by one. and will
327 fallback to default.
328
329if X86_GENERICARCH
330
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331config X86_NUMAQ
332 bool "NUMAQ (IBM/Sequent)"
3de352bb 333 depends on SMP && X86_32 && PCI && X86_MPPARSE
506f1d07 334 select NUMA
506f1d07 335 help
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336 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
337 NUMA multiquad box. This changes the way that processors are
338 bootstrapped, and uses Clustered Logical APIC addressing mode instead
339 of Flat Logical. You will need a new lynxer.elf file to flash your
340 firmware with - send email to <Martin.Bligh@us.ibm.com>.
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341
342config X86_SUMMIT
343 bool "Summit/EXA (IBM x440)"
344 depends on X86_32 && SMP
345 help
346 This option is needed for IBM systems that use the Summit/EXA chipset.
347 In particular, it is needed for the x440.
348
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349config X86_ES7000
350 bool "Support for Unisys ES7000 IA32 series"
351 depends on X86_32 && SMP
352 help
353 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
354 supposed to run on an IA32-based Unisys ES7000 system.
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355
356config X86_BIGSMP
d49c4288 357 bool "Support for big SMP systems with more than 8 CPUs"
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358 depends on X86_32 && SMP
359 help
360 This option is needed for the systems that have more than 8 CPUs
361 and if the system is not of any sub-arch type above.
362
d49c4288 363endif
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364
365config X86_VSMP
366 bool "Support for ScaleMP vSMP"
96597fd2 367 select PARAVIRT
a6784ad7 368 depends on X86_64 && PCI
96597fd2 369 help
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370 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
371 supposed to run on these EM64T-based machines. Only choose this option
372 if you have one of these machines.
373
374endchoice
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375
376config X86_VISWS
377 bool "SGI 320/540 (Visual Workstation)"
39415a44 378 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT
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379 help
380 The SGI Visual Workstation series is an IA32-based workstation
381 based on SGI systems chips with some legacy PC hardware attached.
382
383 Say Y here to create a kernel to run on the SGI 320 or 540.
384
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385 A kernel compiled for the Visual Workstation will run on general
386 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
506f1d07 387
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388config X86_RDC321X
389 bool "RDC R-321x SoC"
390 depends on X86_32
391 select M486
392 select X86_REBOOTFIXUPS
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393 help
394 This option is needed for RDC R-321x system-on-chip, also known
395 as R-8610-(G).
396 If you don't have one of these chips, you should say N here.
397
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398config X86_UV
399 bool "SGI Ultraviolet"
400 depends on X86_64
401 help
402 This option is needed in order to support SGI Ultraviolet systems.
403 If you don't have one of these, you should say N here.
404
ae1e9130 405config SCHED_OMIT_FRAME_POINTER
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406 def_bool y
407 prompt "Single-depth WCHAN output"
a87d0914 408 depends on X86
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409 help
410 Calculate simpler /proc/<PID>/wchan values. If this option
411 is disabled then wchan values will recurse back to the
412 caller function. This provides more accurate wchan values,
413 at the expense of slightly more scheduling overhead.
414
415 If in doubt, say "Y".
416
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417menuconfig PARAVIRT_GUEST
418 bool "Paravirtualized guest support"
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419 help
420 Say Y here to get to see options related to running Linux under
421 various hypervisors. This option alone does not add any kernel code.
422
423 If you say N, all options in this submenu will be skipped and disabled.
424
425if PARAVIRT_GUEST
426
427source "arch/x86/xen/Kconfig"
428
429config VMI
430 bool "VMI Guest support"
431 select PARAVIRT
42d545c9 432 depends on X86_32
efefa6f6 433 depends on !X86_VOYAGER
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434 help
435 VMI provides a paravirtualized interface to the VMware ESX server
436 (it could be used by other hypervisors in theory too, but is not
437 at the moment), by linking the kernel to a GPL-ed ROM module
438 provided by the hypervisor.
439
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440config KVM_CLOCK
441 bool "KVM paravirtualized clock"
442 select PARAVIRT
f6e16d5a 443 select PARAVIRT_CLOCK
efefa6f6 444 depends on !X86_VOYAGER
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445 help
446 Turning on this option will allow you to run a paravirtualized clock
447 when running over the KVM hypervisor. Instead of relying on a PIT
448 (or probably other) emulation by the underlying device model, the host
449 provides the guest with timing infrastructure such as time of day, and
450 system time
451
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452config KVM_GUEST
453 bool "KVM Guest support"
454 select PARAVIRT
efefa6f6 455 depends on !X86_VOYAGER
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456 help
457 This option enables various optimizations for running under the KVM
458 hypervisor.
459
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460source "arch/x86/lguest/Kconfig"
461
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462config PARAVIRT
463 bool "Enable paravirtualization code"
efefa6f6 464 depends on !X86_VOYAGER
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465 help
466 This changes the kernel so it can modify itself when it is run
467 under a hypervisor, potentially improving performance significantly
468 over full virtualization. However, when run without a hypervisor
469 the kernel is theoretically slower and slightly larger.
470
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471config PARAVIRT_CLOCK
472 bool
473 default n
474
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475endif
476
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477config PARAVIRT_DEBUG
478 bool "paravirt-ops debugging"
479 depends on PARAVIRT && DEBUG_KERNEL
480 help
481 Enable to debug paravirt_ops internals. Specifically, BUG if
482 a paravirt_op is missing when it is called.
c64df707 483
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484config MEMTEST
485 bool "Memtest"
c64df707 486 help
c64df707 487 This option adds a kernel parameter 'memtest', which allows memtest
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488 to be set.
489 memtest=0, mean disabled; -- default
490 memtest=1, mean do 1 test pattern;
491 ...
492 memtest=4, mean do 4 test patterns.
aba3728c 493 If you are unsure how to answer this question, answer N.
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494
495config X86_SUMMIT_NUMA
3c2362e6 496 def_bool y
0699eae1 497 depends on X86_32 && NUMA && X86_GENERICARCH
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498
499config X86_CYCLONE_TIMER
3c2362e6 500 def_bool y
0699eae1 501 depends on X86_GENERICARCH
506f1d07 502
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503source "arch/x86/Kconfig.cpu"
504
505config HPET_TIMER
3c2362e6 506 def_bool X86_64
506f1d07 507 prompt "HPET Timer Support" if X86_32
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SR
508 help
509 Use the IA-PC HPET (High Precision Event Timer) to manage
510 time in preference to the PIT and RTC, if a HPET is
511 present.
512 HPET is the next generation timer replacing legacy 8254s.
513 The HPET provides a stable time base on SMP
514 systems, unlike the TSC, but it is more expensive to access,
515 as it is off-chip. You can find the HPET spec at
e45f2c07 516 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
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517
518 You can safely choose Y here. However, HPET will only be
519 activated if the platform and the BIOS support this feature.
520 Otherwise the 8254 will be used for timing services.
521
522 Choose N to continue using the legacy 8254 timer.
523
524config HPET_EMULATE_RTC
3c2362e6 525 def_bool y
9d8af78b 526 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
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527
528# Mark as embedded because too many people got it wrong.
529# The code disables itself when not needed.
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530config DMI
531 default y
532 bool "Enable DMI scanning" if EMBEDDED
533 help
534 Enabled scanning of DMI to identify machine quirks. Say Y
535 here unless you have verified that your setup is not
536 affected by entries in the DMI blacklist. Required by PNP
537 BIOS code.
538
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539config GART_IOMMU
540 bool "GART IOMMU support" if EMBEDDED
541 default y
542 select SWIOTLB
543 select AGP
544 depends on X86_64 && PCI
545 help
546 Support for full DMA access of devices with 32bit memory access only
547 on systems with more than 3GB. This is usually needed for USB,
548 sound, many IDE/SATA chipsets and some other devices.
549 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
550 based hardware IOMMU and a software bounce buffer based IOMMU used
551 on Intel systems and as fallback.
552 The code is only active when needed (enough memory and limited
553 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
554 too.
555
556config CALGARY_IOMMU
557 bool "IBM Calgary IOMMU support"
558 select SWIOTLB
559 depends on X86_64 && PCI && EXPERIMENTAL
560 help
561 Support for hardware IOMMUs in IBM's xSeries x366 and x460
562 systems. Needed to run systems with more than 3GB of memory
563 properly with 32-bit PCI devices that do not support DAC
564 (Double Address Cycle). Calgary also supports bus level
565 isolation, where all DMAs pass through the IOMMU. This
566 prevents them from going anywhere except their intended
567 destination. This catches hard-to-find kernel bugs and
568 mis-behaving drivers and devices that do not use the DMA-API
569 properly to set up their DMA buffers. The IOMMU can be
570 turned off at boot time with the iommu=off parameter.
571 Normally the kernel will make the right choice by itself.
572 If unsure, say Y.
573
574config CALGARY_IOMMU_ENABLED_BY_DEFAULT
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HH
575 def_bool y
576 prompt "Should Calgary be enabled by default?"
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577 depends on CALGARY_IOMMU
578 help
579 Should Calgary be enabled by default? if you choose 'y', Calgary
580 will be used (if it exists). If you choose 'n', Calgary will not be
581 used even if it exists. If you choose 'n' and would like to use
582 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
583 If unsure, say Y.
584
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585config AMD_IOMMU
586 bool "AMD IOMMU support"
07c40e8a 587 select SWIOTLB
a80dc3e0 588 select PCI_MSI
24d2ba0a 589 depends on X86_64 && PCI && ACPI
2b188723 590 help
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JR
591 With this option you can enable support for AMD IOMMU hardware in
592 your system. An IOMMU is a hardware component which provides
593 remapping of DMA memory accesses from devices. With an AMD IOMMU you
594 can isolate the the DMA memory of different devices and protect the
595 system from misbehaving device drivers or hardware.
596
597 You can find out if your system has an AMD IOMMU if you look into
598 your BIOS for an option to enable it or if you have an IVRS ACPI
599 table.
2b188723 600
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JR
601config AMD_IOMMU_STATS
602 bool "Export AMD IOMMU statistics to debugfs"
603 depends on AMD_IOMMU
604 select DEBUG_FS
605 help
606 This option enables code in the AMD IOMMU driver to collect various
607 statistics about whats happening in the driver and exports that
608 information to userspace via debugfs.
609 If unsure, say N.
610
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611# need this always selected by IOMMU for the VIA workaround
612config SWIOTLB
a1afd01c 613 def_bool y if X86_64
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614 help
615 Support for software bounce buffers used on x86-64 systems
616 which don't have a hardware IOMMU (e.g. the current generation
617 of Intel's x86-64 CPUs). Using this PCI devices which can only
618 access 32-bits of memory can be used on systems with more than
619 3 GB of memory. If unsure, say Y.
620
a8522509 621config IOMMU_HELPER
18b743dc 622 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
d25e26b6 623
1aaf1183
JR
624config IOMMU_API
625 def_bool (AMD_IOMMU || DMAR)
626
1184dc2f
MT
627config MAXSMP
628 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
36f5101a
MT
629 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
630 select CPUMASK_OFFSTACK
1184dc2f
MT
631 default n
632 help
633 Configure maximum number of CPUS and NUMA Nodes for this architecture.
634 If unsure, say N.
506f1d07
SR
635
636config NR_CPUS
36f5101a
MT
637 int "Maximum number of CPUs" if SMP && !MAXSMP
638 range 2 512 if SMP && !MAXSMP
78637a97 639 default "1" if !SMP
d25e26b6 640 default "4096" if MAXSMP
78637a97
MT
641 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
642 default "8" if SMP
506f1d07
SR
643 help
644 This allows you to specify the maximum number of CPUs which this
d25e26b6 645 kernel will support. The maximum supported value is 512 and the
506f1d07
SR
646 minimum value which makes sense is 2.
647
648 This is purely to save memory - each supported CPU adds
649 approximately eight kilobytes to the kernel image.
650
651config SCHED_SMT
652 bool "SMT (Hyperthreading) scheduler support"
b089c12b 653 depends on X86_HT
506f1d07
SR
654 help
655 SMT scheduler support improves the CPU scheduler's decision making
656 when dealing with Intel Pentium 4 chips with HyperThreading at a
657 cost of slightly increased overhead in some places. If unsure say
658 N here.
659
660config SCHED_MC
3c2362e6
HH
661 def_bool y
662 prompt "Multi-core scheduler support"
b089c12b 663 depends on X86_HT
506f1d07
SR
664 help
665 Multi-core scheduler support improves the CPU scheduler's decision
666 making when dealing with multi-core CPU chips at a cost of slightly
667 increased overhead in some places. If unsure say N here.
668
669source "kernel/Kconfig.preempt"
670
671config X86_UP_APIC
672 bool "Local APIC support on uniprocessors"
efefa6f6 673 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH)
506f1d07
SR
674 help
675 A local APIC (Advanced Programmable Interrupt Controller) is an
676 integrated interrupt controller in the CPU. If you have a single-CPU
677 system which has a processor with a local APIC, you can say Y here to
678 enable and use it. If you say Y here even though your machine doesn't
679 have a local APIC, then the kernel will still run with no slowdown at
680 all. The local APIC supports CPU-generated self-interrupts (timer,
681 performance counters), and the NMI watchdog which detects hard
682 lockups.
683
684config X86_UP_IOAPIC
685 bool "IO-APIC support on uniprocessors"
686 depends on X86_UP_APIC
687 help
688 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
689 SMP-capable replacement for PC-style interrupt controllers. Most
690 SMP systems and many recent uniprocessor systems have one.
691
692 If you have a single-CPU system with an IO-APIC, you can say Y here
693 to use it. If you say Y here even though your machine doesn't have
694 an IO-APIC, then the kernel will still run with no slowdown at all.
695
696config X86_LOCAL_APIC
3c2362e6 697 def_bool y
efefa6f6 698 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
506f1d07
SR
699
700config X86_IO_APIC
3c2362e6 701 def_bool y
efefa6f6 702 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH))
506f1d07
SR
703
704config X86_VISWS_APIC
3c2362e6 705 def_bool y
506f1d07 706 depends on X86_32 && X86_VISWS
506f1d07 707
41b9eb26
SA
708config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
709 bool "Reroute for broken boot IRQs"
710 default n
711 depends on X86_IO_APIC
712 help
713 This option enables a workaround that fixes a source of
714 spurious interrupts. This is recommended when threaded
715 interrupt handling is used on systems where the generation of
716 superfluous "boot interrupts" cannot be disabled.
717
718 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
719 entry in the chipset's IO-APIC is masked (as, e.g. the RT
720 kernel does during interrupt handling). On chipsets where this
721 boot IRQ generation cannot be disabled, this workaround keeps
722 the original IRQ line masked so that only the equivalent "boot
723 IRQ" is delivered to the CPUs. The workaround also tells the
724 kernel to set up the IRQ handler on the boot IRQ line. In this
725 way only one interrupt is delivered to the kernel. Otherwise
726 the spurious second interrupt may cause the kernel to bring
727 down (vital) interrupt lines.
728
729 Only affects "broken" chipsets. Interrupt sharing may be
730 increased on these systems.
731
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SR
732config X86_MCE
733 bool "Machine Check Exception"
734 depends on !X86_VOYAGER
735 ---help---
736 Machine Check Exception support allows the processor to notify the
737 kernel if it detects a problem (e.g. overheating, component failure).
738 The action the kernel takes depends on the severity of the problem,
739 ranging from a warning message on the console, to halting the machine.
740 Your processor must be a Pentium or newer to support this - check the
741 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
742 have a design flaw which leads to false MCE events - hence MCE is
743 disabled on all P5 processors, unless explicitly enabled with "mce"
744 as a boot argument. Similarly, if MCE is built in and creates a
745 problem on some new non-standard machine, you can boot with "nomce"
746 to disable it. MCE support simply ignores non-MCE processors like
747 the 386 and 486, so nearly everyone can say Y here.
748
749config X86_MCE_INTEL
3c2362e6
HH
750 def_bool y
751 prompt "Intel MCE features"
506f1d07 752 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
506f1d07
SR
753 help
754 Additional support for intel specific MCE features such as
755 the thermal monitor.
756
757config X86_MCE_AMD
3c2362e6
HH
758 def_bool y
759 prompt "AMD MCE features"
506f1d07 760 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
506f1d07
SR
761 help
762 Additional support for AMD specific MCE features such as
763 the DRAM Error Threshold.
764
765config X86_MCE_NONFATAL
766 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
767 depends on X86_32 && X86_MCE
768 help
769 Enabling this feature starts a timer that triggers every 5 seconds which
770 will look at the machine check registers to see if anything happened.
771 Non-fatal problems automatically get corrected (but still logged).
772 Disable this if you don't want to see these messages.
773 Seeing the messages this option prints out may be indicative of dying
774 or out-of-spec (ie, overclocked) hardware.
775 This option only does something on certain CPUs.
776 (AMD Athlon/Duron and Intel Pentium 4)
777
778config X86_MCE_P4THERMAL
779 bool "check for P4 thermal throttling interrupt."
efefa6f6 780 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP)
506f1d07
SR
781 help
782 Enabling this feature will cause a message to be printed when the P4
783 enters thermal throttling.
784
785config VM86
786 bool "Enable VM86 support" if EMBEDDED
787 default y
788 depends on X86_32
789 help
790 This option is required by programs like DOSEMU to run 16-bit legacy
791 code on X86 processors. It also may be needed by software like
792 XFree86 to initialize some video cards via BIOS. Disabling this
793 option saves about 6k.
794
795config TOSHIBA
796 tristate "Toshiba Laptop support"
797 depends on X86_32
798 ---help---
799 This adds a driver to safely access the System Management Mode of
800 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
801 not work on models with a Phoenix BIOS. The System Management Mode
802 is used to set the BIOS and power saving options on Toshiba portables.
803
804 For information on utilities to make use of this driver see the
805 Toshiba Linux utilities web site at:
806 <http://www.buzzard.org.uk/toshiba/>.
807
808 Say Y if you intend to run this kernel on a Toshiba portable.
809 Say N otherwise.
810
811config I8K
812 tristate "Dell laptop support"
506f1d07
SR
813 ---help---
814 This adds a driver to safely access the System Management Mode
815 of the CPU on the Dell Inspiron 8000. The System Management Mode
816 is used to read cpu temperature and cooling fan status and to
817 control the fans on the I8K portables.
818
819 This driver has been tested only on the Inspiron 8000 but it may
820 also work with other Dell laptops. You can force loading on other
821 models by passing the parameter `force=1' to the module. Use at
822 your own risk.
823
824 For information on utilities to make use of this driver see the
825 I8K Linux utilities web site at:
826 <http://people.debian.org/~dz/i8k/>
827
828 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
829 Say N otherwise.
830
831config X86_REBOOTFIXUPS
9ba16087
JB
832 bool "Enable X86 board specific fixups for reboot"
833 depends on X86_32
506f1d07
SR
834 ---help---
835 This enables chipset and/or board specific fixups to be done
836 in order to get reboot to work correctly. This is only needed on
837 some combinations of hardware and BIOS. The symptom, for which
838 this config is intended, is when reboot ends with a stalled/hung
839 system.
840
841 Currently, the only fixup is for the Geode machines using
5e3a77e9 842 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
843
844 Say Y if you want to enable the fixup. Currently, it's safe to
845 enable this option even if you don't need it.
846 Say N otherwise.
847
848config MICROCODE
8d86f390 849 tristate "/dev/cpu/microcode - microcode support"
506f1d07
SR
850 select FW_LOADER
851 ---help---
852 If you say Y here, you will be able to update the microcode on
80cc9f10
PO
853 certain Intel and AMD processors. The Intel support is for the
854 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
855 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
856 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
857 You will obviously need the actual microcode binary data itself
858 which is not shipped with the Linux kernel.
506f1d07 859
8d86f390
PO
860 This option selects the general module only, you need to select
861 at least one vendor specific module as well.
506f1d07
SR
862
863 To compile this driver as a module, choose M here: the
864 module will be called microcode.
865
8d86f390 866config MICROCODE_INTEL
18dbc916 867 bool "Intel microcode patch loading support"
8d86f390
PO
868 depends on MICROCODE
869 default MICROCODE
870 select FW_LOADER
871 --help---
872 This options enables microcode patch loading support for Intel
873 processors.
874
875 For latest news and information on obtaining all the required
876 Intel ingredients for this driver, check:
877 <http://www.urbanmyth.org/microcode/>.
878
80cc9f10 879config MICROCODE_AMD
18dbc916 880 bool "AMD microcode patch loading support"
80cc9f10
PO
881 depends on MICROCODE
882 select FW_LOADER
883 --help---
884 If you select this option, microcode patch loading support for AMD
885 processors will be enabled.
886
8d86f390 887 config MICROCODE_OLD_INTERFACE
3c2362e6 888 def_bool y
506f1d07 889 depends on MICROCODE
506f1d07
SR
890
891config X86_MSR
892 tristate "/dev/cpu/*/msr - Model-specific register support"
893 help
894 This device gives privileged processes access to the x86
895 Model-Specific Registers (MSRs). It is a character device with
896 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
897 MSR accesses are directed to a specific CPU on multi-processor
898 systems.
899
900config X86_CPUID
901 tristate "/dev/cpu/*/cpuid - CPU information support"
902 help
903 This device gives processes access to the x86 CPUID instruction to
904 be executed on a specific processor. It is a character device
905 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
906 /dev/cpu/31/cpuid.
907
908choice
909 prompt "High Memory Support"
910 default HIGHMEM4G if !X86_NUMAQ
911 default HIGHMEM64G if X86_NUMAQ
912 depends on X86_32
913
914config NOHIGHMEM
915 bool "off"
916 depends on !X86_NUMAQ
917 ---help---
918 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
919 However, the address space of 32-bit x86 processors is only 4
920 Gigabytes large. That means that, if you have a large amount of
921 physical memory, not all of it can be "permanently mapped" by the
922 kernel. The physical memory that's not permanently mapped is called
923 "high memory".
924
925 If you are compiling a kernel which will never run on a machine with
926 more than 1 Gigabyte total physical RAM, answer "off" here (default
927 choice and suitable for most users). This will result in a "3GB/1GB"
928 split: 3GB are mapped so that each process sees a 3GB virtual memory
929 space and the remaining part of the 4GB virtual memory space is used
930 by the kernel to permanently map as much physical memory as
931 possible.
932
933 If the machine has between 1 and 4 Gigabytes physical RAM, then
934 answer "4GB" here.
935
936 If more than 4 Gigabytes is used then answer "64GB" here. This
937 selection turns Intel PAE (Physical Address Extension) mode on.
938 PAE implements 3-level paging on IA32 processors. PAE is fully
939 supported by Linux, PAE mode is implemented on all recent Intel
940 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
941 then the kernel will not boot on CPUs that don't support PAE!
942
943 The actual amount of total physical memory will either be
944 auto detected or can be forced by using a kernel command line option
945 such as "mem=256M". (Try "man bootparam" or see the documentation of
946 your boot loader (lilo or loadlin) about how to pass options to the
947 kernel at boot time.)
948
949 If unsure, say "off".
950
951config HIGHMEM4G
952 bool "4GB"
953 depends on !X86_NUMAQ
954 help
955 Select this if you have a 32-bit processor and between 1 and 4
956 gigabytes of physical RAM.
957
958config HIGHMEM64G
959 bool "64GB"
960 depends on !M386 && !M486
961 select X86_PAE
962 help
963 Select this if you have a 32-bit processor and more than 4
964 gigabytes of physical RAM.
965
966endchoice
967
968choice
969 depends on EXPERIMENTAL
970 prompt "Memory split" if EMBEDDED
971 default VMSPLIT_3G
972 depends on X86_32
973 help
974 Select the desired split between kernel and user memory.
975
976 If the address range available to the kernel is less than the
977 physical memory installed, the remaining memory will be available
978 as "high memory". Accessing high memory is a little more costly
979 than low memory, as it needs to be mapped into the kernel first.
980 Note that increasing the kernel address space limits the range
981 available to user programs, making the address space there
982 tighter. Selecting anything other than the default 3G/1G split
983 will also likely make your kernel incompatible with binary-only
984 kernel modules.
985
986 If you are not absolutely sure what you are doing, leave this
987 option alone!
988
989 config VMSPLIT_3G
990 bool "3G/1G user/kernel split"
991 config VMSPLIT_3G_OPT
992 depends on !X86_PAE
993 bool "3G/1G user/kernel split (for full 1G low memory)"
994 config VMSPLIT_2G
995 bool "2G/2G user/kernel split"
996 config VMSPLIT_2G_OPT
997 depends on !X86_PAE
998 bool "2G/2G user/kernel split (for full 2G low memory)"
999 config VMSPLIT_1G
1000 bool "1G/3G user/kernel split"
1001endchoice
1002
1003config PAGE_OFFSET
1004 hex
1005 default 0xB0000000 if VMSPLIT_3G_OPT
1006 default 0x80000000 if VMSPLIT_2G
1007 default 0x78000000 if VMSPLIT_2G_OPT
1008 default 0x40000000 if VMSPLIT_1G
1009 default 0xC0000000
1010 depends on X86_32
1011
1012config HIGHMEM
3c2362e6 1013 def_bool y
506f1d07 1014 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1015
1016config X86_PAE
9ba16087 1017 bool "PAE (Physical Address Extension) Support"
506f1d07 1018 depends on X86_32 && !HIGHMEM4G
506f1d07
SR
1019 help
1020 PAE is required for NX support, and furthermore enables
1021 larger swapspace support for non-overcommit purposes. It
1022 has the cost of more pagetable lookup overhead, and also
1023 consumes more pagetable space per process.
1024
600715dc
JF
1025config ARCH_PHYS_ADDR_T_64BIT
1026 def_bool X86_64 || X86_PAE
1027
9e899816
NP
1028config DIRECT_GBPAGES
1029 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1030 default y
1031 depends on X86_64
1032 help
1033 Allow the kernel linear mapping to use 1GB pages on CPUs that
1034 support it. This can improve the kernel's performance a tiny bit by
1035 reducing TLB pressure. If in doubt, say "Y".
1036
506f1d07
SR
1037# Common NUMA Features
1038config NUMA
fd51b2d7 1039 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1040 depends on SMP
0699eae1 1041 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
506f1d07 1042 default n if X86_PC
0699eae1 1043 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
506f1d07
SR
1044 help
1045 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1046
506f1d07
SR
1047 The kernel will try to allocate memory used by a CPU on the
1048 local memory controller of the CPU and add some more
1049 NUMA awareness to the kernel.
1050
c280ea5e 1051 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1052 (or later), AMD Opteron, or EM64T NUMA.
1053
1054 For 32-bit this is only needed on (rare) 32-bit-only platforms
1055 that support NUMA topologies, such as NUMAQ / Summit, or if you
1056 boot a 32-bit kernel on a 64-bit NUMA platform.
1057
1058 Otherwise, you should say N.
506f1d07
SR
1059
1060comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1061 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1062
1063config K8_NUMA
3c2362e6
HH
1064 def_bool y
1065 prompt "Old style AMD Opteron NUMA detection"
1066 depends on X86_64 && NUMA && PCI
1067 help
506f1d07
SR
1068 Enable K8 NUMA node topology detection. You should say Y here if
1069 you have a multi processor AMD K8 system. This uses an old
1070 method to read the NUMA configuration directly from the builtin
1071 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1072 instead, which also takes priority if both are compiled in.
1073
1074config X86_64_ACPI_NUMA
3c2362e6
HH
1075 def_bool y
1076 prompt "ACPI NUMA detection"
506f1d07
SR
1077 depends on X86_64 && NUMA && ACPI && PCI
1078 select ACPI_NUMA
506f1d07
SR
1079 help
1080 Enable ACPI SRAT based node topology detection.
1081
6ec6e0d9
SS
1082# Some NUMA nodes have memory ranges that span
1083# other nodes. Even though a pfn is valid and
1084# between a node's start and end pfns, it may not
1085# reside on that node. See memmap_init_zone()
1086# for details.
1087config NODES_SPAN_OTHER_NODES
1088 def_bool y
1089 depends on X86_64_ACPI_NUMA
1090
506f1d07
SR
1091config NUMA_EMU
1092 bool "NUMA emulation"
1093 depends on X86_64 && NUMA
1094 help
1095 Enable NUMA emulation. A flat machine will be split
1096 into virtual nodes when booted with "numa=fake=N", where N is the
1097 number of nodes. This is only useful for debugging.
1098
1099config NODES_SHIFT
d25e26b6 1100 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1184dc2f 1101 range 1 9 if X86_64
d25e26b6 1102 default "9" if MAXSMP
506f1d07
SR
1103 default "6" if X86_64
1104 default "4" if X86_NUMAQ
1105 default "3"
1106 depends on NEED_MULTIPLE_NODES
1184dc2f
MT
1107 help
1108 Specify the maximum number of NUMA Nodes available on the target
1109 system. Increases memory reserved to accomodate various tables.
506f1d07
SR
1110
1111config HAVE_ARCH_BOOTMEM_NODE
3c2362e6 1112 def_bool y
506f1d07 1113 depends on X86_32 && NUMA
506f1d07
SR
1114
1115config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1116 def_bool y
506f1d07 1117 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1118
1119config NEED_NODE_MEMMAP_SIZE
3c2362e6 1120 def_bool y
506f1d07 1121 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07
SR
1122
1123config HAVE_ARCH_ALLOC_REMAP
3c2362e6 1124 def_bool y
506f1d07 1125 depends on X86_32 && NUMA
506f1d07
SR
1126
1127config ARCH_FLATMEM_ENABLE
1128 def_bool y
99809963 1129 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
506f1d07
SR
1130
1131config ARCH_DISCONTIGMEM_ENABLE
1132 def_bool y
b263295d 1133 depends on NUMA && X86_32
506f1d07
SR
1134
1135config ARCH_DISCONTIGMEM_DEFAULT
1136 def_bool y
b263295d
CL
1137 depends on NUMA && X86_32
1138
1139config ARCH_SPARSEMEM_DEFAULT
1140 def_bool y
1141 depends on X86_64
506f1d07
SR
1142
1143config ARCH_SPARSEMEM_ENABLE
1144 def_bool y
99809963 1145 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) || X86_GENERICARCH
506f1d07
SR
1146 select SPARSEMEM_STATIC if X86_32
1147 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1148
1149config ARCH_SELECT_MEMORY_MODEL
1150 def_bool y
b263295d 1151 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1152
1153config ARCH_MEMORY_PROBE
1154 def_bool X86_64
1155 depends on MEMORY_HOTPLUG
1156
1157source "mm/Kconfig"
1158
1159config HIGHPTE
1160 bool "Allocate 3rd-level pagetables from highmem"
1161 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1162 help
1163 The VM uses one page table entry for each page of physical memory.
1164 For systems with a lot of RAM, this can be wasteful of precious
1165 low memory. Setting this option will put user-space page table
1166 entries in high memory.
1167
9f077871
JF
1168config X86_CHECK_BIOS_CORRUPTION
1169 bool "Check for low memory corruption"
9f077871
JF
1170 help
1171 Periodically check for memory corruption in low memory, which
1172 is suspected to be caused by BIOS. Even when enabled in the
1173 configuration, it is disabled at runtime. Enable it by
1174 setting "memory_corruption_check=1" on the kernel command
1175 line. By default it scans the low 64k of memory every 60
1176 seconds; see the memory_corruption_check_size and
1177 memory_corruption_check_period parameters in
1178 Documentation/kernel-parameters.txt to adjust this.
1179
1180 When enabled with the default parameters, this option has
1181 almost no overhead, as it reserves a relatively small amount
1182 of memory and scans it infrequently. It both detects corruption
1183 and prevents it from affecting the running system.
1184
1185 It is, however, intended as a diagnostic tool; if repeatable
1186 BIOS-originated corruption always affects the same memory,
1187 you can use memmap= to prevent the kernel from using that
1188 memory.
1189
c885df50
JF
1190config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1191 bool "Set the default setting of memory_corruption_check"
1192 depends on X86_CHECK_BIOS_CORRUPTION
1193 default y
1194 help
1195 Set whether the default state of memory_corruption_check is
1196 on or off.
1197
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IM
1198config X86_RESERVE_LOW_64K
1199 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1200 default y
1201 help
1202 Reserve the first 64K of physical RAM on BIOSes that are known
1203 to potentially corrupt that memory range. A numbers of BIOSes are
1204 known to utilize this area during suspend/resume, so it must not
1205 be used by the kernel.
1206
1207 Set this to N if you are absolutely sure that you trust the BIOS
1208 to get all its memory reservations and usages right.
1209
1210 If you have doubts about the BIOS (e.g. suspend/resume does not
1211 work or there's kernel crashes after certain hardware hotplug
1212 events) and it's not AMI or Phoenix, then you might want to enable
1213 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1214 corruption patterns.
1215
1216 Say Y if unsure.
1217
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SR
1218config MATH_EMULATION
1219 bool
1220 prompt "Math emulation" if X86_32
1221 ---help---
1222 Linux can emulate a math coprocessor (used for floating point
1223 operations) if you don't have one. 486DX and Pentium processors have
1224 a math coprocessor built in, 486SX and 386 do not, unless you added
1225 a 487DX or 387, respectively. (The messages during boot time can
1226 give you some hints here ["man dmesg"].) Everyone needs either a
1227 coprocessor or this emulation.
1228
1229 If you don't have a math coprocessor, you need to say Y here; if you
1230 say Y here even though you have a coprocessor, the coprocessor will
1231 be used nevertheless. (This behavior can be changed with the kernel
1232 command line option "no387", which comes handy if your coprocessor
1233 is broken. Try "man bootparam" or see the documentation of your boot
1234 loader (lilo or loadlin) about how to pass options to the kernel at
1235 boot time.) This means that it is a good idea to say Y here if you
1236 intend to use this kernel on different machines.
1237
1238 More information about the internals of the Linux math coprocessor
1239 emulation can be found in <file:arch/x86/math-emu/README>.
1240
1241 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1242 kernel, it won't hurt.
1243
1244config MTRR
1245 bool "MTRR (Memory Type Range Register) support"
1246 ---help---
1247 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1248 the Memory Type Range Registers (MTRRs) may be used to control
1249 processor access to memory ranges. This is most useful if you have
1250 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1251 allows bus write transfers to be combined into a larger transfer
1252 before bursting over the PCI/AGP bus. This can increase performance
1253 of image write operations 2.5 times or more. Saying Y here creates a
1254 /proc/mtrr file which may be used to manipulate your processor's
1255 MTRRs. Typically the X server should use this.
1256
1257 This code has a reasonably generic interface so that similar
1258 control registers on other processors can be easily supported
1259 as well:
1260
1261 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1262 Registers (ARRs) which provide a similar functionality to MTRRs. For
1263 these, the ARRs are used to emulate the MTRRs.
1264 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1265 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1266 write-combining. All of these processors are supported by this code
1267 and it makes sense to say Y here if you have one of them.
1268
1269 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1270 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1271 can lead to all sorts of problems, so it's good to say Y here.
1272
1273 You can safely say Y even if your machine doesn't have MTRRs, you'll
1274 just add about 9 KB to your kernel.
1275
7225e751 1276 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1277
95ffa243 1278config MTRR_SANITIZER
2ffb3501 1279 def_bool y
95ffa243
YL
1280 prompt "MTRR cleanup support"
1281 depends on MTRR
1282 help
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TG
1283 Convert MTRR layout from continuous to discrete, so X drivers can
1284 add writeback entries.
95ffa243 1285
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TG
1286 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1287 The largest mtrr entry size for a continous block can be set with
1288 mtrr_chunk_size.
95ffa243 1289
2ffb3501 1290 If unsure, say Y.
95ffa243
YL
1291
1292config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1293 int "MTRR cleanup enable value (0-1)"
1294 range 0 1
1295 default "0"
95ffa243
YL
1296 depends on MTRR_SANITIZER
1297 help
f5098d62 1298 Enable mtrr cleanup default value
95ffa243 1299
12031a62
YL
1300config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1301 int "MTRR cleanup spare reg num (0-7)"
1302 range 0 7
1303 default "1"
1304 depends on MTRR_SANITIZER
1305 help
1306 mtrr cleanup spare entries default, it can be changed via
aba3728c 1307 mtrr_spare_reg_nr=N on the kernel command line.
506f1d07 1308
2e5d9c85 1309config X86_PAT
2a8a2719 1310 bool
2e5d9c85 1311 prompt "x86 PAT support"
2a8a2719 1312 depends on MTRR
2e5d9c85 1313 help
1314 Use PAT attributes to setup page level cache control.
042b78e4 1315
2e5d9c85 1316 PATs are the modern equivalents of MTRRs and are much more
1317 flexible than MTRRs.
1318
1319 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1320 spontaneous reboots) or a non-working video driver.
2e5d9c85 1321
1322 If unsure, say Y.
1323
506f1d07 1324config EFI
9ba16087 1325 bool "EFI runtime service support"
5b83683f 1326 depends on ACPI
506f1d07 1327 ---help---
8b2cb7a8 1328 This enables the kernel to use EFI runtime services that are
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SR
1329 available (such as the EFI variable services).
1330
8b2cb7a8
HY
1331 This option is only useful on systems that have EFI firmware.
1332 In addition, you should use the latest ELILO loader available
1333 at <http://elilo.sourceforge.net> in order to take advantage
1334 of EFI runtime services. However, even with this option, the
1335 resultant kernel should continue to boot on existing non-EFI
1336 platforms.
506f1d07 1337
506f1d07 1338config SECCOMP
3c2362e6
HH
1339 def_bool y
1340 prompt "Enable seccomp to safely compute untrusted bytecode"
506f1d07
SR
1341 help
1342 This kernel feature is useful for number crunching applications
1343 that may need to compute untrusted bytecode during their
1344 execution. By using pipes or other transports made available to
1345 the process as file descriptors supporting the read/write
1346 syscalls, it's possible to isolate those applications in
1347 their own address space using seccomp. Once seccomp is
9c0bbee8 1348 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1349 and the task is only allowed to execute a few safe syscalls
1350 defined by each seccomp mode.
1351
1352 If unsure, say Y. Only embedded should say N here.
1353
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IM
1354config CC_STACKPROTECTOR_ALL
1355 bool
1356
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SR
1357config CC_STACKPROTECTOR
1358 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
72370f2a 1359 depends on X86_64
113c5413 1360 select CC_STACKPROTECTOR_ALL
506f1d07 1361 help
113c5413
IM
1362 This option turns on the -fstack-protector GCC feature. This
1363 feature puts, at the beginning of functions, a canary value on
1364 the stack just before the return address, and validates
506f1d07
SR
1365 the value just before actually returning. Stack based buffer
1366 overflows (that need to overwrite this return address) now also
1367 overwrite the canary, which gets detected and the attack is then
1368 neutralized via a kernel panic.
1369
1370 This feature requires gcc version 4.2 or above, or a distribution
1371 gcc with the feature backported. Older versions are automatically
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IM
1372 detected and for those versions, this configuration option is
1373 ignored. (and a warning is printed during bootup)
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SR
1374
1375source kernel/Kconfig.hz
1376
1377config KEXEC
1378 bool "kexec system call"
3e8f7e35 1379 depends on X86_BIOS_REBOOT
506f1d07
SR
1380 help
1381 kexec is a system call that implements the ability to shutdown your
1382 current kernel, and to start another kernel. It is like a reboot
1383 but it is independent of the system firmware. And like a reboot
1384 you can start any kernel with it, not just Linux.
1385
1386 The name comes from the similarity to the exec system call.
1387
1388 It is an ongoing process to be certain the hardware in a machine
1389 is properly shutdown, so do not be surprised if this code does not
1390 initially work for you. It may help to enable device hotplugging
1391 support. As of this writing the exact hardware interface is
1392 strongly in flux, so no good recommendation can be made.
1393
1394config CRASH_DUMP
04b69447 1395 bool "kernel crash dumps"
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SR
1396 depends on X86_64 || (X86_32 && HIGHMEM)
1397 help
1398 Generate crash dump after being started by kexec.
1399 This should be normally only set in special crash dump kernels
1400 which are loaded in the main kernel with kexec-tools into
1401 a specially reserved region and then later executed after
1402 a crash by kdump/kexec. The crash dump kernel must be compiled
1403 to a memory address not used by the main kernel or BIOS using
1404 PHYSICAL_START, or it must be built as a relocatable image
1405 (CONFIG_RELOCATABLE=y).
1406 For more details see Documentation/kdump/kdump.txt
1407
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HY
1408config KEXEC_JUMP
1409 bool "kexec jump (EXPERIMENTAL)"
1410 depends on EXPERIMENTAL
89081d17 1411 depends on KEXEC && HIBERNATION && X86_32
3ab83521 1412 help
89081d17
HY
1413 Jump between original kernel and kexeced kernel and invoke
1414 code in physical address mode via KEXEC
3ab83521 1415
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SR
1416config PHYSICAL_START
1417 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1418 default "0x1000000" if X86_NUMAQ
1419 default "0x200000" if X86_64
1420 default "0x100000"
1421 help
1422 This gives the physical address where the kernel is loaded.
1423
1424 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1425 bzImage will decompress itself to above physical address and
1426 run from there. Otherwise, bzImage will run from the address where
1427 it has been loaded by the boot loader and will ignore above physical
1428 address.
1429
1430 In normal kdump cases one does not have to set/change this option
1431 as now bzImage can be compiled as a completely relocatable image
1432 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1433 address. This option is mainly useful for the folks who don't want
1434 to use a bzImage for capturing the crash dump and want to use a
1435 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1436 to be specifically compiled to run from a specific memory area
1437 (normally a reserved region) and this option comes handy.
1438
1439 So if you are using bzImage for capturing the crash dump, leave
1440 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1441 Otherwise if you plan to use vmlinux for capturing the crash dump
1442 change this value to start of the reserved region (Typically 16MB
1443 0x1000000). In other words, it can be set based on the "X" value as
1444 specified in the "crashkernel=YM@XM" command line boot parameter
1445 passed to the panic-ed kernel. Typically this parameter is set as
1446 crashkernel=64M@16M. Please take a look at
1447 Documentation/kdump/kdump.txt for more details about crash dumps.
1448
1449 Usage of bzImage for capturing the crash dump is recommended as
1450 one does not have to build two kernels. Same kernel can be used
1451 as production kernel and capture kernel. Above option should have
1452 gone away after relocatable bzImage support is introduced. But it
1453 is present because there are users out there who continue to use
1454 vmlinux for dump capture. This option should go away down the
1455 line.
1456
1457 Don't change this unless you know what you are doing.
1458
1459config RELOCATABLE
1460 bool "Build a relocatable kernel (EXPERIMENTAL)"
1461 depends on EXPERIMENTAL
1462 help
1463 This builds a kernel image that retains relocation information
1464 so it can be loaded someplace besides the default 1MB.
1465 The relocations tend to make the kernel binary about 10% larger,
1466 but are discarded at runtime.
1467
1468 One use is for the kexec on panic case where the recovery kernel
1469 must live at a different physical address than the primary
1470 kernel.
1471
1472 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1473 it has been loaded at and the compile time physical address
1474 (CONFIG_PHYSICAL_START) is ignored.
1475
1476config PHYSICAL_ALIGN
1477 hex
1478 prompt "Alignment value to which kernel should be aligned" if X86_32
1479 default "0x100000" if X86_32
1480 default "0x200000" if X86_64
1481 range 0x2000 0x400000
1482 help
1483 This value puts the alignment restrictions on physical address
1484 where kernel is loaded and run from. Kernel is compiled for an
1485 address which meets above alignment restriction.
1486
1487 If bootloader loads the kernel at a non-aligned address and
1488 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1489 address aligned to above value and run from there.
1490
1491 If bootloader loads the kernel at a non-aligned address and
1492 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1493 load address and decompress itself to the address it has been
1494 compiled for and run from there. The address for which kernel is
1495 compiled already meets above alignment restrictions. Hence the
1496 end result is that kernel runs from a physical address meeting
1497 above alignment restrictions.
1498
1499 Don't change this unless you know what you are doing.
1500
1501config HOTPLUG_CPU
7c13e6a3
DS
1502 bool "Support for hot-pluggable CPUs"
1503 depends on SMP && HOTPLUG && !X86_VOYAGER
506f1d07 1504 ---help---
7c13e6a3
DS
1505 Say Y here to allow turning CPUs off and on. CPUs can be
1506 controlled through /sys/devices/system/cpu.
1507 ( Note: power management support will enable this option
1508 automatically on SMP systems. )
1509 Say N if you want to disable CPU hotplug.
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SR
1510
1511config COMPAT_VDSO
3c2362e6
HH
1512 def_bool y
1513 prompt "Compat VDSO support"
af65d648 1514 depends on X86_32 || IA32_EMULATION
506f1d07 1515 help
af65d648 1516 Map the 32-bit VDSO to the predictable old-style address too.
506f1d07
SR
1517 ---help---
1518 Say N here if you are running a sufficiently recent glibc
1519 version (2.3.3 or later), to remove the high-mapped
1520 VDSO mapping and to exclusively use the randomized VDSO.
1521
1522 If unsure, say Y.
1523
516cbf37
TB
1524config CMDLINE_BOOL
1525 bool "Built-in kernel command line"
1526 default n
1527 help
1528 Allow for specifying boot arguments to the kernel at
1529 build time. On some systems (e.g. embedded ones), it is
1530 necessary or convenient to provide some or all of the
1531 kernel boot arguments with the kernel itself (that is,
1532 to not rely on the boot loader to provide them.)
1533
1534 To compile command line arguments into the kernel,
1535 set this option to 'Y', then fill in the
1536 the boot arguments in CONFIG_CMDLINE.
1537
1538 Systems with fully functional boot loaders (i.e. non-embedded)
1539 should leave this option set to 'N'.
1540
1541config CMDLINE
1542 string "Built-in kernel command string"
1543 depends on CMDLINE_BOOL
1544 default ""
1545 help
1546 Enter arguments here that should be compiled into the kernel
1547 image and used at boot time. If the boot loader provides a
1548 command line at boot time, it is appended to this string to
1549 form the full kernel command line, when the system boots.
1550
1551 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1552 change this behavior.
1553
1554 In most cases, the command line (whether built-in or provided
1555 by the boot loader) should specify the device for the root
1556 file system.
1557
1558config CMDLINE_OVERRIDE
1559 bool "Built-in command line overrides boot loader arguments"
1560 default n
1561 depends on CMDLINE_BOOL
1562 help
1563 Set this option to 'Y' to have the kernel ignore the boot loader
1564 command line, and use ONLY the built-in command line.
1565
1566 This is used to work around broken boot loaders. This should
1567 be set to 'N' under normal conditions.
1568
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SR
1569endmenu
1570
1571config ARCH_ENABLE_MEMORY_HOTPLUG
1572 def_bool y
1573 depends on X86_64 || (X86_32 && HIGHMEM)
1574
35551053
GH
1575config ARCH_ENABLE_MEMORY_HOTREMOVE
1576 def_bool y
1577 depends on MEMORY_HOTPLUG
1578
506f1d07
SR
1579config HAVE_ARCH_EARLY_PFN_TO_NID
1580 def_bool X86_64
1581 depends on NUMA
1582
da85f865 1583menu "Power management and ACPI options"
e279b6c1
SR
1584 depends on !X86_VOYAGER
1585
1586config ARCH_HIBERNATION_HEADER
3c2362e6 1587 def_bool y
e279b6c1 1588 depends on X86_64 && HIBERNATION
e279b6c1
SR
1589
1590source "kernel/power/Kconfig"
1591
1592source "drivers/acpi/Kconfig"
1593
a6b68076
AK
1594config X86_APM_BOOT
1595 bool
1596 default y
1597 depends on APM || APM_MODULE
1598
e279b6c1
SR
1599menuconfig APM
1600 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 1601 depends on X86_32 && PM_SLEEP
e279b6c1
SR
1602 ---help---
1603 APM is a BIOS specification for saving power using several different
1604 techniques. This is mostly useful for battery powered laptops with
1605 APM compliant BIOSes. If you say Y here, the system time will be
1606 reset after a RESUME operation, the /proc/apm device will provide
1607 battery status information, and user-space programs will receive
1608 notification of APM "events" (e.g. battery status change).
1609
1610 If you select "Y" here, you can disable actual use of the APM
1611 BIOS by passing the "apm=off" option to the kernel at boot time.
1612
1613 Note that the APM support is almost completely disabled for
1614 machines with more than one CPU.
1615
1616 In order to use APM, you will need supporting software. For location
53471121 1617 and more information, read <file:Documentation/power/pm.txt> and the
e279b6c1
SR
1618 Battery Powered Linux mini-HOWTO, available from
1619 <http://www.tldp.org/docs.html#howto>.
1620
1621 This driver does not spin down disk drives (see the hdparm(8)
1622 manpage ("man 8 hdparm") for that), and it doesn't turn off
1623 VESA-compliant "green" monitors.
1624
1625 This driver does not support the TI 4000M TravelMate and the ACER
1626 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1627 desktop machines also don't have compliant BIOSes, and this driver
1628 may cause those machines to panic during the boot phase.
1629
1630 Generally, if you don't have a battery in your machine, there isn't
1631 much point in using this driver and you should say N. If you get
1632 random kernel OOPSes or reboots that don't seem to be related to
1633 anything, try disabling/enabling this option (or disabling/enabling
1634 APM in your BIOS).
1635
1636 Some other things you should try when experiencing seemingly random,
1637 "weird" problems:
1638
1639 1) make sure that you have enough swap space and that it is
1640 enabled.
1641 2) pass the "no-hlt" option to the kernel
1642 3) switch on floating point emulation in the kernel and pass
1643 the "no387" option to the kernel
1644 4) pass the "floppy=nodma" option to the kernel
1645 5) pass the "mem=4M" option to the kernel (thereby disabling
1646 all but the first 4 MB of RAM)
1647 6) make sure that the CPU is not over clocked.
1648 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1649 8) disable the cache from your BIOS settings
1650 9) install a fan for the video card or exchange video RAM
1651 10) install a better fan for the CPU
1652 11) exchange RAM chips
1653 12) exchange the motherboard.
1654
1655 To compile this driver as a module, choose M here: the
1656 module will be called apm.
1657
1658if APM
1659
1660config APM_IGNORE_USER_SUSPEND
1661 bool "Ignore USER SUSPEND"
1662 help
1663 This option will ignore USER SUSPEND requests. On machines with a
1664 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1665 series notebooks, it is necessary to say Y because of a BIOS bug.
1666
1667config APM_DO_ENABLE
1668 bool "Enable PM at boot time"
1669 ---help---
1670 Enable APM features at boot time. From page 36 of the APM BIOS
1671 specification: "When disabled, the APM BIOS does not automatically
1672 power manage devices, enter the Standby State, enter the Suspend
1673 State, or take power saving steps in response to CPU Idle calls."
1674 This driver will make CPU Idle calls when Linux is idle (unless this
1675 feature is turned off -- see "Do CPU IDLE calls", below). This
1676 should always save battery power, but more complicated APM features
1677 will be dependent on your BIOS implementation. You may need to turn
1678 this option off if your computer hangs at boot time when using APM
1679 support, or if it beeps continuously instead of suspending. Turn
1680 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1681 T400CDT. This is off by default since most machines do fine without
1682 this feature.
1683
1684config APM_CPU_IDLE
1685 bool "Make CPU Idle calls when idle"
1686 help
1687 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1688 On some machines, this can activate improved power savings, such as
1689 a slowed CPU clock rate, when the machine is idle. These idle calls
1690 are made after the idle loop has run for some length of time (e.g.,
1691 333 mS). On some machines, this will cause a hang at boot time or
1692 whenever the CPU becomes idle. (On machines with more than one CPU,
1693 this option does nothing.)
1694
1695config APM_DISPLAY_BLANK
1696 bool "Enable console blanking using APM"
1697 help
1698 Enable console blanking using the APM. Some laptops can use this to
1699 turn off the LCD backlight when the screen blanker of the Linux
1700 virtual console blanks the screen. Note that this is only used by
1701 the virtual console screen blanker, and won't turn off the backlight
1702 when using the X Window system. This also doesn't have anything to
1703 do with your VESA-compliant power-saving monitor. Further, this
1704 option doesn't work for all laptops -- it might not turn off your
1705 backlight at all, or it might print a lot of errors to the console,
1706 especially if you are using gpm.
1707
1708config APM_ALLOW_INTS
1709 bool "Allow interrupts during APM BIOS calls"
1710 help
1711 Normally we disable external interrupts while we are making calls to
1712 the APM BIOS as a measure to lessen the effects of a badly behaving
1713 BIOS implementation. The BIOS should reenable interrupts if it
1714 needs to. Unfortunately, some BIOSes do not -- especially those in
1715 many of the newer IBM Thinkpads. If you experience hangs when you
1716 suspend, try setting this to Y. Otherwise, say N.
1717
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SR
1718endif # APM
1719
1720source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1721
1722source "drivers/cpuidle/Kconfig"
1723
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AH
1724source "drivers/idle/Kconfig"
1725
e279b6c1
SR
1726endmenu
1727
1728
1729menu "Bus options (PCI etc.)"
1730
1731config PCI
1ac97018 1732 bool "PCI support"
1c858087 1733 default y
e279b6c1
SR
1734 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1735 help
1736 Find out whether you have a PCI motherboard. PCI is the name of a
1737 bus system, i.e. the way the CPU talks to the other stuff inside
1738 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1739 VESA. If you have PCI, say Y, otherwise N.
1740
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SR
1741choice
1742 prompt "PCI access mode"
efefa6f6 1743 depends on X86_32 && PCI
e279b6c1
SR
1744 default PCI_GOANY
1745 ---help---
1746 On PCI systems, the BIOS can be used to detect the PCI devices and
1747 determine their configuration. However, some old PCI motherboards
1748 have BIOS bugs and may crash if this is done. Also, some embedded
1749 PCI-based systems don't have any BIOS at all. Linux can also try to
1750 detect the PCI hardware directly without using the BIOS.
1751
1752 With this option, you can specify how Linux should detect the
1753 PCI devices. If you choose "BIOS", the BIOS will be used,
1754 if you choose "Direct", the BIOS won't be used, and if you
1755 choose "MMConfig", then PCI Express MMCONFIG will be used.
1756 If you choose "Any", the kernel will try MMCONFIG, then the
1757 direct access method and falls back to the BIOS if that doesn't
1758 work. If unsure, go with the default, which is "Any".
1759
1760config PCI_GOBIOS
1761 bool "BIOS"
1762
1763config PCI_GOMMCONFIG
1764 bool "MMConfig"
1765
1766config PCI_GODIRECT
1767 bool "Direct"
1768
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1769config PCI_GOOLPC
1770 bool "OLPC"
1771 depends on OLPC
1772
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1773config PCI_GOANY
1774 bool "Any"
1775
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1776endchoice
1777
1778config PCI_BIOS
3c2362e6 1779 def_bool y
efefa6f6 1780 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
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1781
1782# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1783config PCI_DIRECT
3c2362e6 1784 def_bool y
efefa6f6 1785 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
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1786
1787config PCI_MMCONFIG
3c2362e6 1788 def_bool y
e279b6c1 1789 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 1790
3ef0e1f8 1791config PCI_OLPC
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1792 def_bool y
1793 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 1794
e279b6c1 1795config PCI_DOMAINS
3c2362e6 1796 def_bool y
e279b6c1 1797 depends on PCI
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1798
1799config PCI_MMCONFIG
1800 bool "Support mmconfig PCI config space access"
1801 depends on X86_64 && PCI && ACPI
1802
1803config DMAR
1804 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1805 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1806 help
1807 DMA remapping (DMAR) devices support enables independent address
1808 translations for Direct Memory Access (DMA) from devices.
1809 These DMA remapping devices are reported via ACPI tables
1810 and include PCI device scope covered by these DMA
1811 remapping devices.
1812
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1813config DMAR_DEFAULT_ON
1814 def_bool n
1815 prompt "Enable DMA Remapping Devices by default"
1816 depends on DMAR
1817 help
1818 Selecting this option will enable a DMAR device at boot time if
1819 one is found. If this option is not selected, DMAR support can
1820 be enabled by passing intel_iommu=on to the kernel. It is
1821 recommended you say N here while the DMAR code remains
1822 experimental.
1823
e279b6c1 1824config DMAR_GFX_WA
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1825 def_bool y
1826 prompt "Support for Graphics workaround"
e279b6c1 1827 depends on DMAR
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1828 help
1829 Current Graphics drivers tend to use physical address
1830 for DMA and avoid using DMA APIs. Setting this config
1831 option permits the IOMMU driver to set a unity map for
1832 all the OS-visible memory. Hence the driver can continue
1833 to use physical addresses for DMA.
1834
1835config DMAR_FLOPPY_WA
3c2362e6 1836 def_bool y
e279b6c1 1837 depends on DMAR
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1838 help
1839 Floppy disk drivers are know to bypass DMA API calls
1840 thereby failing to work when IOMMU is enabled. This
1841 workaround will setup a 1:1 mapping for the first
1842 16M to make floppy (an ISA device) work.
1843
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1844config INTR_REMAP
1845 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1846 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1847 help
1848 Supports Interrupt remapping for IO-APIC and MSI devices.
1849 To use x2apic mode in the CPU's which support x2APIC enhancements or
1850 to support platforms with CPU's having > 8 bit APIC ID, say Y.
1851
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1852source "drivers/pci/pcie/Kconfig"
1853
1854source "drivers/pci/Kconfig"
1855
1856# x86_64 have no ISA slots, but do have ISA-style DMA.
1857config ISA_DMA_API
3c2362e6 1858 def_bool y
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1859
1860if X86_32
1861
1862config ISA
1863 bool "ISA support"
efefa6f6 1864 depends on !X86_VOYAGER
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1865 help
1866 Find out whether you have ISA slots on your motherboard. ISA is the
1867 name of a bus system, i.e. the way the CPU talks to the other stuff
1868 inside your box. Other bus systems are PCI, EISA, MicroChannel
1869 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1870 newer boards don't support it. If you have ISA, say Y, otherwise N.
1871
1872config EISA
1873 bool "EISA support"
1874 depends on ISA
1875 ---help---
1876 The Extended Industry Standard Architecture (EISA) bus was
1877 developed as an open alternative to the IBM MicroChannel bus.
1878
1879 The EISA bus provided some of the features of the IBM MicroChannel
1880 bus while maintaining backward compatibility with cards made for
1881 the older ISA bus. The EISA bus saw limited use between 1988 and
1882 1995 when it was made obsolete by the PCI bus.
1883
1884 Say Y here if you are building a kernel for an EISA-based machine.
1885
1886 Otherwise, say N.
1887
1888source "drivers/eisa/Kconfig"
1889
1890config MCA
efefa6f6 1891 bool "MCA support" if !X86_VOYAGER
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1892 default y if X86_VOYAGER
1893 help
1894 MicroChannel Architecture is found in some IBM PS/2 machines and
1895 laptops. It is a bus system similar to PCI or ISA. See
1896 <file:Documentation/mca.txt> (and especially the web page given
1897 there) before attempting to build an MCA bus kernel.
1898
1899source "drivers/mca/Kconfig"
1900
1901config SCx200
1902 tristate "NatSemi SCx200 support"
1903 depends on !X86_VOYAGER
1904 help
1905 This provides basic support for National Semiconductor's
1906 (now AMD's) Geode processors. The driver probes for the
1907 PCI-IDs of several on-chip devices, so its a good dependency
1908 for other scx200_* drivers.
1909
1910 If compiled as a module, the driver is named scx200.
1911
1912config SCx200HR_TIMER
1913 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1914 depends on SCx200 && GENERIC_TIME
1915 default y
1916 help
1917 This driver provides a clocksource built upon the on-chip
1918 27MHz high-resolution timer. Its also a workaround for
1919 NSC Geode SC-1100's buggy TSC, which loses time when the
1920 processor goes idle (as is done by the scheduler). The
1921 other workaround is idle=poll boot option.
1922
1923config GEODE_MFGPT_TIMER
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1924 def_bool y
1925 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
e279b6c1 1926 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
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1927 help
1928 This driver provides a clock event source based on the MFGPT
1929 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1930 MFGPTs have a better resolution and max interval than the
1931 generic PIT, and are suitable for use as high-res timers.
1932
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1933config OLPC
1934 bool "One Laptop Per Child support"
1935 default n
1936 help
1937 Add support for detecting the unique features of the OLPC
1938 XO hardware.
1939
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1940endif # X86_32
1941
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1942config K8_NB
1943 def_bool y
bc0120fd 1944 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
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1945
1946source "drivers/pcmcia/Kconfig"
1947
1948source "drivers/pci/hotplug/Kconfig"
1949
1950endmenu
1951
1952
1953menu "Executable file formats / Emulations"
1954
1955source "fs/Kconfig.binfmt"
1956
1957config IA32_EMULATION
1958 bool "IA32 Emulation"
1959 depends on X86_64
a97f52e6 1960 select COMPAT_BINFMT_ELF
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1961 help
1962 Include code to run 32-bit programs under a 64-bit kernel. You should
1963 likely turn this on, unless you're 100% sure that you don't have any
1964 32-bit programs left.
1965
1966config IA32_AOUT
1967 tristate "IA32 a.out support"
6b213e1b 1968 depends on IA32_EMULATION
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1969 help
1970 Support old a.out binaries in the 32bit emulation.
1971
1972config COMPAT
3c2362e6 1973 def_bool y
e279b6c1 1974 depends on IA32_EMULATION
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1975
1976config COMPAT_FOR_U64_ALIGNMENT
1977 def_bool COMPAT
1978 depends on X86_64
1979
1980config SYSVIPC_COMPAT
3c2362e6 1981 def_bool y
b8992195 1982 depends on COMPAT && SYSVIPC
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1983
1984endmenu
1985
1986
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1987config HAVE_ATOMIC_IOMAP
1988 def_bool y
1989 depends on X86_32
1990
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1991source "net/Kconfig"
1992
1993source "drivers/Kconfig"
1994
1995source "drivers/firmware/Kconfig"
1996
1997source "fs/Kconfig"
1998
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1999source "arch/x86/Kconfig.debug"
2000
2001source "security/Kconfig"
2002
2003source "crypto/Kconfig"
2004
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2005source "arch/x86/kvm/Kconfig"
2006
e279b6c1 2007source "lib/Kconfig"