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1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH != "i386"
5 ---help---
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9 config X86_32
10 def_bool y
11 depends on !64BIT
12
13 config X86_64
14 def_bool y
15 depends on 64BIT
16
17 ### Arch settings
18 config X86
19 def_bool y
20 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
22 select ANON_INODES
23 select ARCH_CLOCKSOURCE_DATA
24 select ARCH_DISCARD_MEMBLOCK
25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
27 select ARCH_HAS_ELF_RANDOMIZE
28 select ARCH_HAS_FAST_MULTIPLIER
29 select ARCH_HAS_GCOV_PROFILE_ALL
30 select ARCH_HAS_SG_CHAIN
31 select ARCH_HAVE_NMI_SAFE_CMPXCHG
32 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
33 select ARCH_MIGHT_HAVE_PC_PARPORT
34 select ARCH_MIGHT_HAVE_PC_SERIO
35 select ARCH_SUPPORTS_ATOMIC_RMW
36 select ARCH_SUPPORTS_INT128 if X86_64
37 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
38 select ARCH_USE_BUILTIN_BSWAP
39 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
40 select ARCH_USE_QUEUED_RWLOCKS
41 select ARCH_USE_QUEUED_SPINLOCKS
42 select ARCH_WANT_FRAME_POINTERS
43 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
44 select ARCH_WANT_OPTIONAL_GPIOLIB
45 select BUILDTIME_EXTABLE_SORT
46 select CLKEVT_I8253
47 select CLKSRC_I8253 if X86_32
48 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
49 select CLOCKSOURCE_WATCHDOG
50 select CLONE_BACKWARDS if X86_32
51 select COMPAT_OLD_SIGACTION if IA32_EMULATION
52 select DCACHE_WORD_ACCESS
53 select EDAC_ATOMIC_SCRUB
54 select EDAC_SUPPORT
55 select GENERIC_CLOCKEVENTS
56 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
57 select GENERIC_CLOCKEVENTS_MIN_ADJUST
58 select GENERIC_CMOS_UPDATE
59 select GENERIC_CPU_AUTOPROBE
60 select GENERIC_EARLY_IOREMAP
61 select GENERIC_FIND_FIRST_BIT
62 select GENERIC_IOMAP
63 select GENERIC_IRQ_PROBE
64 select GENERIC_IRQ_SHOW
65 select GENERIC_PENDING_IRQ if SMP
66 select GENERIC_SMP_IDLE_THREAD
67 select GENERIC_STRNCPY_FROM_USER
68 select GENERIC_STRNLEN_USER
69 select GENERIC_TIME_VSYSCALL
70 select HAVE_ACPI_APEI if ACPI
71 select HAVE_ACPI_APEI_NMI if ACPI
72 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
73 select HAVE_AOUT if X86_32
74 select HAVE_ARCH_AUDITSYSCALL
75 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
76 select HAVE_ARCH_JUMP_LABEL
77 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
78 select HAVE_ARCH_KGDB
79 select HAVE_ARCH_KMEMCHECK
80 select HAVE_ARCH_SECCOMP_FILTER
81 select HAVE_ARCH_SOFT_DIRTY if X86_64
82 select HAVE_ARCH_TRACEHOOK
83 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
84 select HAVE_BPF_JIT if X86_64
85 select HAVE_CC_STACKPROTECTOR
86 select HAVE_CMPXCHG_DOUBLE
87 select HAVE_CMPXCHG_LOCAL
88 select HAVE_CONTEXT_TRACKING if X86_64
89 select HAVE_C_RECORDMCOUNT
90 select HAVE_DEBUG_KMEMLEAK
91 select HAVE_DEBUG_STACKOVERFLOW
92 select HAVE_DMA_API_DEBUG
93 select HAVE_DMA_ATTRS
94 select HAVE_DMA_CONTIGUOUS
95 select HAVE_DYNAMIC_FTRACE
96 select HAVE_DYNAMIC_FTRACE_WITH_REGS
97 select HAVE_EFFICIENT_UNALIGNED_ACCESS
98 select HAVE_FENTRY if X86_64
99 select HAVE_FTRACE_MCOUNT_RECORD
100 select HAVE_FUNCTION_GRAPH_FP_TEST
101 select HAVE_FUNCTION_GRAPH_TRACER
102 select HAVE_FUNCTION_TRACER
103 select HAVE_GENERIC_DMA_COHERENT if X86_32
104 select HAVE_HW_BREAKPOINT
105 select HAVE_IDE
106 select HAVE_IOREMAP_PROT
107 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
108 select HAVE_IRQ_TIME_ACCOUNTING
109 select HAVE_KERNEL_BZIP2
110 select HAVE_KERNEL_GZIP
111 select HAVE_KERNEL_LZ4
112 select HAVE_KERNEL_LZMA
113 select HAVE_KERNEL_LZO
114 select HAVE_KERNEL_XZ
115 select HAVE_KPROBES
116 select HAVE_KPROBES_ON_FTRACE
117 select HAVE_KRETPROBES
118 select HAVE_KVM
119 select HAVE_LIVEPATCH if X86_64
120 select HAVE_MEMBLOCK
121 select HAVE_MEMBLOCK_NODE_MAP
122 select HAVE_MIXED_BREAKPOINTS_REGS
123 select HAVE_OPROFILE
124 select HAVE_OPTPROBES
125 select HAVE_PCSPKR_PLATFORM
126 select HAVE_PERF_EVENTS
127 select HAVE_PERF_EVENTS_NMI
128 select HAVE_PERF_REGS
129 select HAVE_PERF_USER_STACK_DUMP
130 select HAVE_REGS_AND_STACK_ACCESS_API
131 select HAVE_SYSCALL_TRACEPOINTS
132 select HAVE_UID16 if X86_32
133 select HAVE_UNSTABLE_SCHED_CLOCK
134 select HAVE_USER_RETURN_NOTIFIER
135 select IRQ_FORCED_THREADING
136 select MODULES_USE_ELF_RELA if X86_64
137 select MODULES_USE_ELF_REL if X86_32
138 select OLD_SIGACTION if X86_32
139 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
140 select PERF_EVENTS
141 select RTC_LIB
142 select SPARSE_IRQ
143 select SRCU
144 select SYSCTL_EXCEPTION_TRACE
145 select USER_STACKTRACE_SUPPORT
146 select VIRT_TO_BUS
147 select X86_DEV_DMA_OPS if X86_64
148 select X86_FEATURE_NAMES if PROC_FS
149
150 config INSTRUCTION_DECODER
151 def_bool y
152 depends on KPROBES || PERF_EVENTS || UPROBES
153
154 config PERF_EVENTS_INTEL_UNCORE
155 def_bool y
156 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
157
158 config OUTPUT_FORMAT
159 string
160 default "elf32-i386" if X86_32
161 default "elf64-x86-64" if X86_64
162
163 config ARCH_DEFCONFIG
164 string
165 default "arch/x86/configs/i386_defconfig" if X86_32
166 default "arch/x86/configs/x86_64_defconfig" if X86_64
167
168 config LOCKDEP_SUPPORT
169 def_bool y
170
171 config STACKTRACE_SUPPORT
172 def_bool y
173
174 config HAVE_LATENCYTOP_SUPPORT
175 def_bool y
176
177 config MMU
178 def_bool y
179
180 config SBUS
181 bool
182
183 config NEED_DMA_MAP_STATE
184 def_bool y
185 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
186
187 config NEED_SG_DMA_LENGTH
188 def_bool y
189
190 config GENERIC_ISA_DMA
191 def_bool y
192 depends on ISA_DMA_API
193
194 config GENERIC_BUG
195 def_bool y
196 depends on BUG
197 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
198
199 config GENERIC_BUG_RELATIVE_POINTERS
200 bool
201
202 config GENERIC_HWEIGHT
203 def_bool y
204
205 config ARCH_MAY_HAVE_PC_FDC
206 def_bool y
207 depends on ISA_DMA_API
208
209 config RWSEM_XCHGADD_ALGORITHM
210 def_bool y
211
212 config GENERIC_CALIBRATE_DELAY
213 def_bool y
214
215 config ARCH_HAS_CPU_RELAX
216 def_bool y
217
218 config ARCH_HAS_CACHE_LINE_SIZE
219 def_bool y
220
221 config HAVE_SETUP_PER_CPU_AREA
222 def_bool y
223
224 config NEED_PER_CPU_EMBED_FIRST_CHUNK
225 def_bool y
226
227 config NEED_PER_CPU_PAGE_FIRST_CHUNK
228 def_bool y
229
230 config ARCH_HIBERNATION_POSSIBLE
231 def_bool y
232
233 config ARCH_SUSPEND_POSSIBLE
234 def_bool y
235
236 config ARCH_WANT_HUGE_PMD_SHARE
237 def_bool y
238
239 config ARCH_WANT_GENERAL_HUGETLB
240 def_bool y
241
242 config ZONE_DMA32
243 def_bool y if X86_64
244
245 config AUDIT_ARCH
246 def_bool y if X86_64
247
248 config ARCH_SUPPORTS_OPTIMIZED_INLINING
249 def_bool y
250
251 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
252 def_bool y
253
254 config HAVE_INTEL_TXT
255 def_bool y
256 depends on INTEL_IOMMU && ACPI
257
258 config X86_32_SMP
259 def_bool y
260 depends on X86_32 && SMP
261
262 config X86_64_SMP
263 def_bool y
264 depends on X86_64 && SMP
265
266 config X86_32_LAZY_GS
267 def_bool y
268 depends on X86_32 && !CC_STACKPROTECTOR
269
270 config ARCH_HWEIGHT_CFLAGS
271 string
272 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
273 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
274
275 config ARCH_SUPPORTS_UPROBES
276 def_bool y
277
278 config FIX_EARLYCON_MEM
279 def_bool y
280
281 config PGTABLE_LEVELS
282 int
283 default 4 if X86_64
284 default 3 if X86_PAE
285 default 2
286
287 source "init/Kconfig"
288 source "kernel/Kconfig.freezer"
289
290 menu "Processor type and features"
291
292 config ZONE_DMA
293 bool "DMA memory allocation support" if EXPERT
294 default y
295 help
296 DMA memory allocation support allows devices with less than 32-bit
297 addressing to allocate within the first 16MB of address space.
298 Disable if no such devices will be used.
299
300 If unsure, say Y.
301
302 config SMP
303 bool "Symmetric multi-processing support"
304 ---help---
305 This enables support for systems with more than one CPU. If you have
306 a system with only one CPU, say N. If you have a system with more
307 than one CPU, say Y.
308
309 If you say N here, the kernel will run on uni- and multiprocessor
310 machines, but will use only one CPU of a multiprocessor machine. If
311 you say Y here, the kernel will run on many, but not all,
312 uniprocessor machines. On a uniprocessor machine, the kernel
313 will run faster if you say N here.
314
315 Note that if you say Y here and choose architecture "586" or
316 "Pentium" under "Processor family", the kernel will not work on 486
317 architectures. Similarly, multiprocessor kernels for the "PPro"
318 architecture may not work on all Pentium based boards.
319
320 People using multiprocessor machines who say Y here should also say
321 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
322 Management" code will be disabled if you say Y here.
323
324 See also <file:Documentation/x86/i386/IO-APIC.txt>,
325 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
326 <http://www.tldp.org/docs.html#howto>.
327
328 If you don't know what to do here, say N.
329
330 config X86_FEATURE_NAMES
331 bool "Processor feature human-readable names" if EMBEDDED
332 default y
333 ---help---
334 This option compiles in a table of x86 feature bits and corresponding
335 names. This is required to support /proc/cpuinfo and a few kernel
336 messages. You can disable this to save space, at the expense of
337 making those few kernel messages show numeric feature bits instead.
338
339 If in doubt, say Y.
340
341 config X86_X2APIC
342 bool "Support x2apic"
343 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
344 ---help---
345 This enables x2apic support on CPUs that have this feature.
346
347 This allows 32-bit apic IDs (so it can support very large systems),
348 and accesses the local apic via MSRs not via mmio.
349
350 If you don't know what to do here, say N.
351
352 config X86_MPPARSE
353 bool "Enable MPS table" if ACPI || SFI
354 default y
355 depends on X86_LOCAL_APIC
356 ---help---
357 For old smp systems that do not have proper acpi support. Newer systems
358 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
359
360 config X86_BIGSMP
361 bool "Support for big SMP systems with more than 8 CPUs"
362 depends on X86_32 && SMP
363 ---help---
364 This option is needed for the systems that have more than 8 CPUs
365
366 config GOLDFISH
367 def_bool y
368 depends on X86_GOLDFISH
369
370 if X86_32
371 config X86_EXTENDED_PLATFORM
372 bool "Support for extended (non-PC) x86 platforms"
373 default y
374 ---help---
375 If you disable this option then the kernel will only support
376 standard PC platforms. (which covers the vast majority of
377 systems out there.)
378
379 If you enable this option then you'll be able to select support
380 for the following (non-PC) 32 bit x86 platforms:
381 Goldfish (Android emulator)
382 AMD Elan
383 RDC R-321x SoC
384 SGI 320/540 (Visual Workstation)
385 STA2X11-based (e.g. Northville)
386 Moorestown MID devices
387
388 If you have one of these systems, or if you want to build a
389 generic distribution kernel, say Y here - otherwise say N.
390 endif
391
392 if X86_64
393 config X86_EXTENDED_PLATFORM
394 bool "Support for extended (non-PC) x86 platforms"
395 default y
396 ---help---
397 If you disable this option then the kernel will only support
398 standard PC platforms. (which covers the vast majority of
399 systems out there.)
400
401 If you enable this option then you'll be able to select support
402 for the following (non-PC) 64 bit x86 platforms:
403 Numascale NumaChip
404 ScaleMP vSMP
405 SGI Ultraviolet
406
407 If you have one of these systems, or if you want to build a
408 generic distribution kernel, say Y here - otherwise say N.
409 endif
410 # This is an alphabetically sorted list of 64 bit extended platforms
411 # Please maintain the alphabetic order if and when there are additions
412 config X86_NUMACHIP
413 bool "Numascale NumaChip"
414 depends on X86_64
415 depends on X86_EXTENDED_PLATFORM
416 depends on NUMA
417 depends on SMP
418 depends on X86_X2APIC
419 depends on PCI_MMCONFIG
420 ---help---
421 Adds support for Numascale NumaChip large-SMP systems. Needed to
422 enable more than ~168 cores.
423 If you don't have one of these, you should say N here.
424
425 config X86_VSMP
426 bool "ScaleMP vSMP"
427 select HYPERVISOR_GUEST
428 select PARAVIRT
429 depends on X86_64 && PCI
430 depends on X86_EXTENDED_PLATFORM
431 depends on SMP
432 ---help---
433 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
434 supposed to run on these EM64T-based machines. Only choose this option
435 if you have one of these machines.
436
437 config X86_UV
438 bool "SGI Ultraviolet"
439 depends on X86_64
440 depends on X86_EXTENDED_PLATFORM
441 depends on NUMA
442 depends on X86_X2APIC
443 depends on PCI
444 ---help---
445 This option is needed in order to support SGI Ultraviolet systems.
446 If you don't have one of these, you should say N here.
447
448 # Following is an alphabetically sorted list of 32 bit extended platforms
449 # Please maintain the alphabetic order if and when there are additions
450
451 config X86_GOLDFISH
452 bool "Goldfish (Virtual Platform)"
453 depends on X86_EXTENDED_PLATFORM
454 ---help---
455 Enable support for the Goldfish virtual platform used primarily
456 for Android development. Unless you are building for the Android
457 Goldfish emulator say N here.
458
459 config X86_INTEL_CE
460 bool "CE4100 TV platform"
461 depends on PCI
462 depends on PCI_GODIRECT
463 depends on X86_IO_APIC
464 depends on X86_32
465 depends on X86_EXTENDED_PLATFORM
466 select X86_REBOOTFIXUPS
467 select OF
468 select OF_EARLY_FLATTREE
469 ---help---
470 Select for the Intel CE media processor (CE4100) SOC.
471 This option compiles in support for the CE4100 SOC for settop
472 boxes and media devices.
473
474 config X86_INTEL_MID
475 bool "Intel MID platform support"
476 depends on X86_32
477 depends on X86_EXTENDED_PLATFORM
478 depends on X86_PLATFORM_DEVICES
479 depends on PCI
480 depends on PCI_GOANY
481 depends on X86_IO_APIC
482 select SFI
483 select I2C
484 select DW_APB_TIMER
485 select APB_TIMER
486 select INTEL_SCU_IPC
487 select MFD_INTEL_MSIC
488 ---help---
489 Select to build a kernel capable of supporting Intel MID (Mobile
490 Internet Device) platform systems which do not have the PCI legacy
491 interfaces. If you are building for a PC class system say N here.
492
493 Intel MID platforms are based on an Intel processor and chipset which
494 consume less power than most of the x86 derivatives.
495
496 config X86_INTEL_QUARK
497 bool "Intel Quark platform support"
498 depends on X86_32
499 depends on X86_EXTENDED_PLATFORM
500 depends on X86_PLATFORM_DEVICES
501 depends on X86_TSC
502 depends on PCI
503 depends on PCI_GOANY
504 depends on X86_IO_APIC
505 select IOSF_MBI
506 select INTEL_IMR
507 select COMMON_CLK
508 ---help---
509 Select to include support for Quark X1000 SoC.
510 Say Y here if you have a Quark based system such as the Arduino
511 compatible Intel Galileo.
512
513 config X86_INTEL_LPSS
514 bool "Intel Low Power Subsystem Support"
515 depends on ACPI
516 select COMMON_CLK
517 select PINCTRL
518 ---help---
519 Select to build support for Intel Low Power Subsystem such as
520 found on Intel Lynxpoint PCH. Selecting this option enables
521 things like clock tree (common clock framework) and pincontrol
522 which are needed by the LPSS peripheral drivers.
523
524 config X86_AMD_PLATFORM_DEVICE
525 bool "AMD ACPI2Platform devices support"
526 depends on ACPI
527 select COMMON_CLK
528 select PINCTRL
529 ---help---
530 Select to interpret AMD specific ACPI device to platform device
531 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
532 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
533 implemented under PINCTRL subsystem.
534
535 config IOSF_MBI
536 tristate "Intel SoC IOSF Sideband support for SoC platforms"
537 depends on PCI
538 ---help---
539 This option enables sideband register access support for Intel SoC
540 platforms. On these platforms the IOSF sideband is used in lieu of
541 MSR's for some register accesses, mostly but not limited to thermal
542 and power. Drivers may query the availability of this device to
543 determine if they need the sideband in order to work on these
544 platforms. The sideband is available on the following SoC products.
545 This list is not meant to be exclusive.
546 - BayTrail
547 - Braswell
548 - Quark
549
550 You should say Y if you are running a kernel on one of these SoC's.
551
552 config IOSF_MBI_DEBUG
553 bool "Enable IOSF sideband access through debugfs"
554 depends on IOSF_MBI && DEBUG_FS
555 ---help---
556 Select this option to expose the IOSF sideband access registers (MCR,
557 MDR, MCRX) through debugfs to write and read register information from
558 different units on the SoC. This is most useful for obtaining device
559 state information for debug and analysis. As this is a general access
560 mechanism, users of this option would have specific knowledge of the
561 device they want to access.
562
563 If you don't require the option or are in doubt, say N.
564
565 config X86_RDC321X
566 bool "RDC R-321x SoC"
567 depends on X86_32
568 depends on X86_EXTENDED_PLATFORM
569 select M486
570 select X86_REBOOTFIXUPS
571 ---help---
572 This option is needed for RDC R-321x system-on-chip, also known
573 as R-8610-(G).
574 If you don't have one of these chips, you should say N here.
575
576 config X86_32_NON_STANDARD
577 bool "Support non-standard 32-bit SMP architectures"
578 depends on X86_32 && SMP
579 depends on X86_EXTENDED_PLATFORM
580 ---help---
581 This option compiles in the bigsmp and STA2X11 default
582 subarchitectures. It is intended for a generic binary
583 kernel. If you select them all, kernel will probe it one by
584 one and will fallback to default.
585
586 # Alphabetically sorted list of Non standard 32 bit platforms
587
588 config X86_SUPPORTS_MEMORY_FAILURE
589 def_bool y
590 # MCE code calls memory_failure():
591 depends on X86_MCE
592 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
593 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
594 depends on X86_64 || !SPARSEMEM
595 select ARCH_SUPPORTS_MEMORY_FAILURE
596
597 config STA2X11
598 bool "STA2X11 Companion Chip Support"
599 depends on X86_32_NON_STANDARD && PCI
600 select X86_DEV_DMA_OPS
601 select X86_DMA_REMAP
602 select SWIOTLB
603 select MFD_STA2X11
604 select ARCH_REQUIRE_GPIOLIB
605 default n
606 ---help---
607 This adds support for boards based on the STA2X11 IO-Hub,
608 a.k.a. "ConneXt". The chip is used in place of the standard
609 PC chipset, so all "standard" peripherals are missing. If this
610 option is selected the kernel will still be able to boot on
611 standard PC machines.
612
613 config X86_32_IRIS
614 tristate "Eurobraille/Iris poweroff module"
615 depends on X86_32
616 ---help---
617 The Iris machines from EuroBraille do not have APM or ACPI support
618 to shut themselves down properly. A special I/O sequence is
619 needed to do so, which is what this module does at
620 kernel shutdown.
621
622 This is only for Iris machines from EuroBraille.
623
624 If unused, say N.
625
626 config SCHED_OMIT_FRAME_POINTER
627 def_bool y
628 prompt "Single-depth WCHAN output"
629 depends on X86
630 ---help---
631 Calculate simpler /proc/<PID>/wchan values. If this option
632 is disabled then wchan values will recurse back to the
633 caller function. This provides more accurate wchan values,
634 at the expense of slightly more scheduling overhead.
635
636 If in doubt, say "Y".
637
638 menuconfig HYPERVISOR_GUEST
639 bool "Linux guest support"
640 ---help---
641 Say Y here to enable options for running Linux under various hyper-
642 visors. This option enables basic hypervisor detection and platform
643 setup.
644
645 If you say N, all options in this submenu will be skipped and
646 disabled, and Linux guest support won't be built in.
647
648 if HYPERVISOR_GUEST
649
650 config PARAVIRT
651 bool "Enable paravirtualization code"
652 ---help---
653 This changes the kernel so it can modify itself when it is run
654 under a hypervisor, potentially improving performance significantly
655 over full virtualization. However, when run without a hypervisor
656 the kernel is theoretically slower and slightly larger.
657
658 config PARAVIRT_DEBUG
659 bool "paravirt-ops debugging"
660 depends on PARAVIRT && DEBUG_KERNEL
661 ---help---
662 Enable to debug paravirt_ops internals. Specifically, BUG if
663 a paravirt_op is missing when it is called.
664
665 config PARAVIRT_SPINLOCKS
666 bool "Paravirtualization layer for spinlocks"
667 depends on PARAVIRT && SMP
668 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
669 ---help---
670 Paravirtualized spinlocks allow a pvops backend to replace the
671 spinlock implementation with something virtualization-friendly
672 (for example, block the virtual CPU rather than spinning).
673
674 It has a minimal impact on native kernels and gives a nice performance
675 benefit on paravirtualized KVM / Xen kernels.
676
677 If you are unsure how to answer this question, answer Y.
678
679 source "arch/x86/xen/Kconfig"
680
681 config KVM_GUEST
682 bool "KVM Guest support (including kvmclock)"
683 depends on PARAVIRT
684 select PARAVIRT_CLOCK
685 default y
686 ---help---
687 This option enables various optimizations for running under the KVM
688 hypervisor. It includes a paravirtualized clock, so that instead
689 of relying on a PIT (or probably other) emulation by the
690 underlying device model, the host provides the guest with
691 timing infrastructure such as time of day, and system time
692
693 config KVM_DEBUG_FS
694 bool "Enable debug information for KVM Guests in debugfs"
695 depends on KVM_GUEST && DEBUG_FS
696 default n
697 ---help---
698 This option enables collection of various statistics for KVM guest.
699 Statistics are displayed in debugfs filesystem. Enabling this option
700 may incur significant overhead.
701
702 source "arch/x86/lguest/Kconfig"
703
704 config PARAVIRT_TIME_ACCOUNTING
705 bool "Paravirtual steal time accounting"
706 depends on PARAVIRT
707 default n
708 ---help---
709 Select this option to enable fine granularity task steal time
710 accounting. Time spent executing other tasks in parallel with
711 the current vCPU is discounted from the vCPU power. To account for
712 that, there can be a small performance impact.
713
714 If in doubt, say N here.
715
716 config PARAVIRT_CLOCK
717 bool
718
719 endif #HYPERVISOR_GUEST
720
721 config NO_BOOTMEM
722 def_bool y
723
724 source "arch/x86/Kconfig.cpu"
725
726 config HPET_TIMER
727 def_bool X86_64
728 prompt "HPET Timer Support" if X86_32
729 ---help---
730 Use the IA-PC HPET (High Precision Event Timer) to manage
731 time in preference to the PIT and RTC, if a HPET is
732 present.
733 HPET is the next generation timer replacing legacy 8254s.
734 The HPET provides a stable time base on SMP
735 systems, unlike the TSC, but it is more expensive to access,
736 as it is off-chip. You can find the HPET spec at
737 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
738
739 You can safely choose Y here. However, HPET will only be
740 activated if the platform and the BIOS support this feature.
741 Otherwise the 8254 will be used for timing services.
742
743 Choose N to continue using the legacy 8254 timer.
744
745 config HPET_EMULATE_RTC
746 def_bool y
747 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
748
749 config APB_TIMER
750 def_bool y if X86_INTEL_MID
751 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
752 select DW_APB_TIMER
753 depends on X86_INTEL_MID && SFI
754 help
755 APB timer is the replacement for 8254, HPET on X86 MID platforms.
756 The APBT provides a stable time base on SMP
757 systems, unlike the TSC, but it is more expensive to access,
758 as it is off-chip. APB timers are always running regardless of CPU
759 C states, they are used as per CPU clockevent device when possible.
760
761 # Mark as expert because too many people got it wrong.
762 # The code disables itself when not needed.
763 config DMI
764 default y
765 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
766 bool "Enable DMI scanning" if EXPERT
767 ---help---
768 Enabled scanning of DMI to identify machine quirks. Say Y
769 here unless you have verified that your setup is not
770 affected by entries in the DMI blacklist. Required by PNP
771 BIOS code.
772
773 config GART_IOMMU
774 bool "Old AMD GART IOMMU support"
775 select SWIOTLB
776 depends on X86_64 && PCI && AMD_NB
777 ---help---
778 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
779 GART based hardware IOMMUs.
780
781 The GART supports full DMA access for devices with 32-bit access
782 limitations, on systems with more than 3 GB. This is usually needed
783 for USB, sound, many IDE/SATA chipsets and some other devices.
784
785 Newer systems typically have a modern AMD IOMMU, supported via
786 the CONFIG_AMD_IOMMU=y config option.
787
788 In normal configurations this driver is only active when needed:
789 there's more than 3 GB of memory and the system contains a
790 32-bit limited device.
791
792 If unsure, say Y.
793
794 config CALGARY_IOMMU
795 bool "IBM Calgary IOMMU support"
796 select SWIOTLB
797 depends on X86_64 && PCI
798 ---help---
799 Support for hardware IOMMUs in IBM's xSeries x366 and x460
800 systems. Needed to run systems with more than 3GB of memory
801 properly with 32-bit PCI devices that do not support DAC
802 (Double Address Cycle). Calgary also supports bus level
803 isolation, where all DMAs pass through the IOMMU. This
804 prevents them from going anywhere except their intended
805 destination. This catches hard-to-find kernel bugs and
806 mis-behaving drivers and devices that do not use the DMA-API
807 properly to set up their DMA buffers. The IOMMU can be
808 turned off at boot time with the iommu=off parameter.
809 Normally the kernel will make the right choice by itself.
810 If unsure, say Y.
811
812 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
813 def_bool y
814 prompt "Should Calgary be enabled by default?"
815 depends on CALGARY_IOMMU
816 ---help---
817 Should Calgary be enabled by default? if you choose 'y', Calgary
818 will be used (if it exists). If you choose 'n', Calgary will not be
819 used even if it exists. If you choose 'n' and would like to use
820 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
821 If unsure, say Y.
822
823 # need this always selected by IOMMU for the VIA workaround
824 config SWIOTLB
825 def_bool y if X86_64
826 ---help---
827 Support for software bounce buffers used on x86-64 systems
828 which don't have a hardware IOMMU. Using this PCI devices
829 which can only access 32-bits of memory can be used on systems
830 with more than 3 GB of memory.
831 If unsure, say Y.
832
833 config IOMMU_HELPER
834 def_bool y
835 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
836
837 config MAXSMP
838 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
839 depends on X86_64 && SMP && DEBUG_KERNEL
840 select CPUMASK_OFFSTACK
841 ---help---
842 Enable maximum number of CPUS and NUMA Nodes for this architecture.
843 If unsure, say N.
844
845 config NR_CPUS
846 int "Maximum number of CPUs" if SMP && !MAXSMP
847 range 2 8 if SMP && X86_32 && !X86_BIGSMP
848 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
849 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
850 default "1" if !SMP
851 default "8192" if MAXSMP
852 default "32" if SMP && X86_BIGSMP
853 default "8" if SMP && X86_32
854 default "64" if SMP
855 ---help---
856 This allows you to specify the maximum number of CPUs which this
857 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
858 supported value is 8192, otherwise the maximum value is 512. The
859 minimum value which makes sense is 2.
860
861 This is purely to save memory - each supported CPU adds
862 approximately eight kilobytes to the kernel image.
863
864 config SCHED_SMT
865 bool "SMT (Hyperthreading) scheduler support"
866 depends on SMP
867 ---help---
868 SMT scheduler support improves the CPU scheduler's decision making
869 when dealing with Intel Pentium 4 chips with HyperThreading at a
870 cost of slightly increased overhead in some places. If unsure say
871 N here.
872
873 config SCHED_MC
874 def_bool y
875 prompt "Multi-core scheduler support"
876 depends on SMP
877 ---help---
878 Multi-core scheduler support improves the CPU scheduler's decision
879 making when dealing with multi-core CPU chips at a cost of slightly
880 increased overhead in some places. If unsure say N here.
881
882 source "kernel/Kconfig.preempt"
883
884 config UP_LATE_INIT
885 def_bool y
886 depends on !SMP && X86_LOCAL_APIC
887
888 config X86_UP_APIC
889 bool "Local APIC support on uniprocessors" if !PCI_MSI
890 default PCI_MSI
891 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
892 ---help---
893 A local APIC (Advanced Programmable Interrupt Controller) is an
894 integrated interrupt controller in the CPU. If you have a single-CPU
895 system which has a processor with a local APIC, you can say Y here to
896 enable and use it. If you say Y here even though your machine doesn't
897 have a local APIC, then the kernel will still run with no slowdown at
898 all. The local APIC supports CPU-generated self-interrupts (timer,
899 performance counters), and the NMI watchdog which detects hard
900 lockups.
901
902 config X86_UP_IOAPIC
903 bool "IO-APIC support on uniprocessors"
904 depends on X86_UP_APIC
905 ---help---
906 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
907 SMP-capable replacement for PC-style interrupt controllers. Most
908 SMP systems and many recent uniprocessor systems have one.
909
910 If you have a single-CPU system with an IO-APIC, you can say Y here
911 to use it. If you say Y here even though your machine doesn't have
912 an IO-APIC, then the kernel will still run with no slowdown at all.
913
914 config X86_LOCAL_APIC
915 def_bool y
916 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
917 select IRQ_DOMAIN_HIERARCHY
918 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
919
920 config X86_IO_APIC
921 def_bool y
922 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
923
924 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
925 bool "Reroute for broken boot IRQs"
926 depends on X86_IO_APIC
927 ---help---
928 This option enables a workaround that fixes a source of
929 spurious interrupts. This is recommended when threaded
930 interrupt handling is used on systems where the generation of
931 superfluous "boot interrupts" cannot be disabled.
932
933 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
934 entry in the chipset's IO-APIC is masked (as, e.g. the RT
935 kernel does during interrupt handling). On chipsets where this
936 boot IRQ generation cannot be disabled, this workaround keeps
937 the original IRQ line masked so that only the equivalent "boot
938 IRQ" is delivered to the CPUs. The workaround also tells the
939 kernel to set up the IRQ handler on the boot IRQ line. In this
940 way only one interrupt is delivered to the kernel. Otherwise
941 the spurious second interrupt may cause the kernel to bring
942 down (vital) interrupt lines.
943
944 Only affects "broken" chipsets. Interrupt sharing may be
945 increased on these systems.
946
947 config X86_MCE
948 bool "Machine Check / overheating reporting"
949 default y
950 ---help---
951 Machine Check support allows the processor to notify the
952 kernel if it detects a problem (e.g. overheating, data corruption).
953 The action the kernel takes depends on the severity of the problem,
954 ranging from warning messages to halting the machine.
955
956 config X86_MCE_INTEL
957 def_bool y
958 prompt "Intel MCE features"
959 depends on X86_MCE && X86_LOCAL_APIC
960 ---help---
961 Additional support for intel specific MCE features such as
962 the thermal monitor.
963
964 config X86_MCE_AMD
965 def_bool y
966 prompt "AMD MCE features"
967 depends on X86_MCE && X86_LOCAL_APIC
968 ---help---
969 Additional support for AMD specific MCE features such as
970 the DRAM Error Threshold.
971
972 config X86_ANCIENT_MCE
973 bool "Support for old Pentium 5 / WinChip machine checks"
974 depends on X86_32 && X86_MCE
975 ---help---
976 Include support for machine check handling on old Pentium 5 or WinChip
977 systems. These typically need to be enabled explicitly on the command
978 line.
979
980 config X86_MCE_THRESHOLD
981 depends on X86_MCE_AMD || X86_MCE_INTEL
982 def_bool y
983
984 config X86_MCE_INJECT
985 depends on X86_MCE
986 tristate "Machine check injector support"
987 ---help---
988 Provide support for injecting machine checks for testing purposes.
989 If you don't know what a machine check is and you don't do kernel
990 QA it is safe to say n.
991
992 config X86_THERMAL_VECTOR
993 def_bool y
994 depends on X86_MCE_INTEL
995
996 config VM86
997 bool "Enable VM86 support" if EXPERT
998 default y
999 depends on X86_32
1000 ---help---
1001 This option is required by programs like DOSEMU to run
1002 16-bit real mode legacy code on x86 processors. It also may
1003 be needed by software like XFree86 to initialize some video
1004 cards via BIOS. Disabling this option saves about 6K.
1005
1006 config X86_16BIT
1007 bool "Enable support for 16-bit segments" if EXPERT
1008 default y
1009 ---help---
1010 This option is required by programs like Wine to run 16-bit
1011 protected mode legacy code on x86 processors. Disabling
1012 this option saves about 300 bytes on i386, or around 6K text
1013 plus 16K runtime memory on x86-64,
1014
1015 config X86_ESPFIX32
1016 def_bool y
1017 depends on X86_16BIT && X86_32
1018
1019 config X86_ESPFIX64
1020 def_bool y
1021 depends on X86_16BIT && X86_64
1022
1023 config X86_VSYSCALL_EMULATION
1024 bool "Enable vsyscall emulation" if EXPERT
1025 default y
1026 depends on X86_64
1027 ---help---
1028 This enables emulation of the legacy vsyscall page. Disabling
1029 it is roughly equivalent to booting with vsyscall=none, except
1030 that it will also disable the helpful warning if a program
1031 tries to use a vsyscall. With this option set to N, offending
1032 programs will just segfault, citing addresses of the form
1033 0xffffffffff600?00.
1034
1035 This option is required by many programs built before 2013, and
1036 care should be used even with newer programs if set to N.
1037
1038 Disabling this option saves about 7K of kernel size and
1039 possibly 4K of additional runtime pagetable memory.
1040
1041 config TOSHIBA
1042 tristate "Toshiba Laptop support"
1043 depends on X86_32
1044 ---help---
1045 This adds a driver to safely access the System Management Mode of
1046 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1047 not work on models with a Phoenix BIOS. The System Management Mode
1048 is used to set the BIOS and power saving options on Toshiba portables.
1049
1050 For information on utilities to make use of this driver see the
1051 Toshiba Linux utilities web site at:
1052 <http://www.buzzard.org.uk/toshiba/>.
1053
1054 Say Y if you intend to run this kernel on a Toshiba portable.
1055 Say N otherwise.
1056
1057 config I8K
1058 tristate "Dell i8k legacy laptop support"
1059 select HWMON
1060 select SENSORS_DELL_SMM
1061 ---help---
1062 This option enables legacy /proc/i8k userspace interface in hwmon
1063 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1064 temperature and allows controlling fan speeds of Dell laptops via
1065 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1066 it reports also power and hotkey status. For fan speed control is
1067 needed userspace package i8kutils.
1068
1069 Say Y if you intend to run this kernel on old Dell laptops or want to
1070 use userspace package i8kutils.
1071 Say N otherwise.
1072
1073 config X86_REBOOTFIXUPS
1074 bool "Enable X86 board specific fixups for reboot"
1075 depends on X86_32
1076 ---help---
1077 This enables chipset and/or board specific fixups to be done
1078 in order to get reboot to work correctly. This is only needed on
1079 some combinations of hardware and BIOS. The symptom, for which
1080 this config is intended, is when reboot ends with a stalled/hung
1081 system.
1082
1083 Currently, the only fixup is for the Geode machines using
1084 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1085
1086 Say Y if you want to enable the fixup. Currently, it's safe to
1087 enable this option even if you don't need it.
1088 Say N otherwise.
1089
1090 config MICROCODE
1091 tristate "CPU microcode loading support"
1092 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1093 select FW_LOADER
1094 ---help---
1095
1096 If you say Y here, you will be able to update the microcode on
1097 certain Intel and AMD processors. The Intel support is for the
1098 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1099 Xeon etc. The AMD support is for families 0x10 and later. You will
1100 obviously need the actual microcode binary data itself which is not
1101 shipped with the Linux kernel.
1102
1103 This option selects the general module only, you need to select
1104 at least one vendor specific module as well.
1105
1106 To compile this driver as a module, choose M here: the module
1107 will be called microcode.
1108
1109 config MICROCODE_INTEL
1110 bool "Intel microcode loading support"
1111 depends on MICROCODE
1112 default MICROCODE
1113 select FW_LOADER
1114 ---help---
1115 This options enables microcode patch loading support for Intel
1116 processors.
1117
1118 For the current Intel microcode data package go to
1119 <https://downloadcenter.intel.com> and search for
1120 'Linux Processor Microcode Data File'.
1121
1122 config MICROCODE_AMD
1123 bool "AMD microcode loading support"
1124 depends on MICROCODE
1125 select FW_LOADER
1126 ---help---
1127 If you select this option, microcode patch loading support for AMD
1128 processors will be enabled.
1129
1130 config MICROCODE_OLD_INTERFACE
1131 def_bool y
1132 depends on MICROCODE
1133
1134 config MICROCODE_INTEL_EARLY
1135 bool
1136
1137 config MICROCODE_AMD_EARLY
1138 bool
1139
1140 config MICROCODE_EARLY
1141 bool "Early load microcode"
1142 depends on MICROCODE=y && BLK_DEV_INITRD
1143 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1144 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1145 default y
1146 help
1147 This option provides functionality to read additional microcode data
1148 at the beginning of initrd image. The data tells kernel to load
1149 microcode to CPU's as early as possible. No functional change if no
1150 microcode data is glued to the initrd, therefore it's safe to say Y.
1151
1152 config X86_MSR
1153 tristate "/dev/cpu/*/msr - Model-specific register support"
1154 ---help---
1155 This device gives privileged processes access to the x86
1156 Model-Specific Registers (MSRs). It is a character device with
1157 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1158 MSR accesses are directed to a specific CPU on multi-processor
1159 systems.
1160
1161 config X86_CPUID
1162 tristate "/dev/cpu/*/cpuid - CPU information support"
1163 ---help---
1164 This device gives processes access to the x86 CPUID instruction to
1165 be executed on a specific processor. It is a character device
1166 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1167 /dev/cpu/31/cpuid.
1168
1169 choice
1170 prompt "High Memory Support"
1171 default HIGHMEM4G
1172 depends on X86_32
1173
1174 config NOHIGHMEM
1175 bool "off"
1176 ---help---
1177 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1178 However, the address space of 32-bit x86 processors is only 4
1179 Gigabytes large. That means that, if you have a large amount of
1180 physical memory, not all of it can be "permanently mapped" by the
1181 kernel. The physical memory that's not permanently mapped is called
1182 "high memory".
1183
1184 If you are compiling a kernel which will never run on a machine with
1185 more than 1 Gigabyte total physical RAM, answer "off" here (default
1186 choice and suitable for most users). This will result in a "3GB/1GB"
1187 split: 3GB are mapped so that each process sees a 3GB virtual memory
1188 space and the remaining part of the 4GB virtual memory space is used
1189 by the kernel to permanently map as much physical memory as
1190 possible.
1191
1192 If the machine has between 1 and 4 Gigabytes physical RAM, then
1193 answer "4GB" here.
1194
1195 If more than 4 Gigabytes is used then answer "64GB" here. This
1196 selection turns Intel PAE (Physical Address Extension) mode on.
1197 PAE implements 3-level paging on IA32 processors. PAE is fully
1198 supported by Linux, PAE mode is implemented on all recent Intel
1199 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1200 then the kernel will not boot on CPUs that don't support PAE!
1201
1202 The actual amount of total physical memory will either be
1203 auto detected or can be forced by using a kernel command line option
1204 such as "mem=256M". (Try "man bootparam" or see the documentation of
1205 your boot loader (lilo or loadlin) about how to pass options to the
1206 kernel at boot time.)
1207
1208 If unsure, say "off".
1209
1210 config HIGHMEM4G
1211 bool "4GB"
1212 ---help---
1213 Select this if you have a 32-bit processor and between 1 and 4
1214 gigabytes of physical RAM.
1215
1216 config HIGHMEM64G
1217 bool "64GB"
1218 depends on !M486
1219 select X86_PAE
1220 ---help---
1221 Select this if you have a 32-bit processor and more than 4
1222 gigabytes of physical RAM.
1223
1224 endchoice
1225
1226 choice
1227 prompt "Memory split" if EXPERT
1228 default VMSPLIT_3G
1229 depends on X86_32
1230 ---help---
1231 Select the desired split between kernel and user memory.
1232
1233 If the address range available to the kernel is less than the
1234 physical memory installed, the remaining memory will be available
1235 as "high memory". Accessing high memory is a little more costly
1236 than low memory, as it needs to be mapped into the kernel first.
1237 Note that increasing the kernel address space limits the range
1238 available to user programs, making the address space there
1239 tighter. Selecting anything other than the default 3G/1G split
1240 will also likely make your kernel incompatible with binary-only
1241 kernel modules.
1242
1243 If you are not absolutely sure what you are doing, leave this
1244 option alone!
1245
1246 config VMSPLIT_3G
1247 bool "3G/1G user/kernel split"
1248 config VMSPLIT_3G_OPT
1249 depends on !X86_PAE
1250 bool "3G/1G user/kernel split (for full 1G low memory)"
1251 config VMSPLIT_2G
1252 bool "2G/2G user/kernel split"
1253 config VMSPLIT_2G_OPT
1254 depends on !X86_PAE
1255 bool "2G/2G user/kernel split (for full 2G low memory)"
1256 config VMSPLIT_1G
1257 bool "1G/3G user/kernel split"
1258 endchoice
1259
1260 config PAGE_OFFSET
1261 hex
1262 default 0xB0000000 if VMSPLIT_3G_OPT
1263 default 0x80000000 if VMSPLIT_2G
1264 default 0x78000000 if VMSPLIT_2G_OPT
1265 default 0x40000000 if VMSPLIT_1G
1266 default 0xC0000000
1267 depends on X86_32
1268
1269 config HIGHMEM
1270 def_bool y
1271 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1272
1273 config X86_PAE
1274 bool "PAE (Physical Address Extension) Support"
1275 depends on X86_32 && !HIGHMEM4G
1276 ---help---
1277 PAE is required for NX support, and furthermore enables
1278 larger swapspace support for non-overcommit purposes. It
1279 has the cost of more pagetable lookup overhead, and also
1280 consumes more pagetable space per process.
1281
1282 config ARCH_PHYS_ADDR_T_64BIT
1283 def_bool y
1284 depends on X86_64 || X86_PAE
1285
1286 config ARCH_DMA_ADDR_T_64BIT
1287 def_bool y
1288 depends on X86_64 || HIGHMEM64G
1289
1290 config X86_DIRECT_GBPAGES
1291 def_bool y
1292 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1293 ---help---
1294 Certain kernel features effectively disable kernel
1295 linear 1 GB mappings (even if the CPU otherwise
1296 supports them), so don't confuse the user by printing
1297 that we have them enabled.
1298
1299 # Common NUMA Features
1300 config NUMA
1301 bool "Numa Memory Allocation and Scheduler Support"
1302 depends on SMP
1303 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1304 default y if X86_BIGSMP
1305 ---help---
1306 Enable NUMA (Non Uniform Memory Access) support.
1307
1308 The kernel will try to allocate memory used by a CPU on the
1309 local memory controller of the CPU and add some more
1310 NUMA awareness to the kernel.
1311
1312 For 64-bit this is recommended if the system is Intel Core i7
1313 (or later), AMD Opteron, or EM64T NUMA.
1314
1315 For 32-bit this is only needed if you boot a 32-bit
1316 kernel on a 64-bit NUMA platform.
1317
1318 Otherwise, you should say N.
1319
1320 config AMD_NUMA
1321 def_bool y
1322 prompt "Old style AMD Opteron NUMA detection"
1323 depends on X86_64 && NUMA && PCI
1324 ---help---
1325 Enable AMD NUMA node topology detection. You should say Y here if
1326 you have a multi processor AMD system. This uses an old method to
1327 read the NUMA configuration directly from the builtin Northbridge
1328 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1329 which also takes priority if both are compiled in.
1330
1331 config X86_64_ACPI_NUMA
1332 def_bool y
1333 prompt "ACPI NUMA detection"
1334 depends on X86_64 && NUMA && ACPI && PCI
1335 select ACPI_NUMA
1336 ---help---
1337 Enable ACPI SRAT based node topology detection.
1338
1339 # Some NUMA nodes have memory ranges that span
1340 # other nodes. Even though a pfn is valid and
1341 # between a node's start and end pfns, it may not
1342 # reside on that node. See memmap_init_zone()
1343 # for details.
1344 config NODES_SPAN_OTHER_NODES
1345 def_bool y
1346 depends on X86_64_ACPI_NUMA
1347
1348 config NUMA_EMU
1349 bool "NUMA emulation"
1350 depends on NUMA
1351 ---help---
1352 Enable NUMA emulation. A flat machine will be split
1353 into virtual nodes when booted with "numa=fake=N", where N is the
1354 number of nodes. This is only useful for debugging.
1355
1356 config NODES_SHIFT
1357 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1358 range 1 10
1359 default "10" if MAXSMP
1360 default "6" if X86_64
1361 default "3"
1362 depends on NEED_MULTIPLE_NODES
1363 ---help---
1364 Specify the maximum number of NUMA Nodes available on the target
1365 system. Increases memory reserved to accommodate various tables.
1366
1367 config ARCH_HAVE_MEMORY_PRESENT
1368 def_bool y
1369 depends on X86_32 && DISCONTIGMEM
1370
1371 config NEED_NODE_MEMMAP_SIZE
1372 def_bool y
1373 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1374
1375 config ARCH_FLATMEM_ENABLE
1376 def_bool y
1377 depends on X86_32 && !NUMA
1378
1379 config ARCH_DISCONTIGMEM_ENABLE
1380 def_bool y
1381 depends on NUMA && X86_32
1382
1383 config ARCH_DISCONTIGMEM_DEFAULT
1384 def_bool y
1385 depends on NUMA && X86_32
1386
1387 config ARCH_SPARSEMEM_ENABLE
1388 def_bool y
1389 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1390 select SPARSEMEM_STATIC if X86_32
1391 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1392
1393 config ARCH_SPARSEMEM_DEFAULT
1394 def_bool y
1395 depends on X86_64
1396
1397 config ARCH_SELECT_MEMORY_MODEL
1398 def_bool y
1399 depends on ARCH_SPARSEMEM_ENABLE
1400
1401 config ARCH_MEMORY_PROBE
1402 bool "Enable sysfs memory/probe interface"
1403 depends on X86_64 && MEMORY_HOTPLUG
1404 help
1405 This option enables a sysfs memory/probe interface for testing.
1406 See Documentation/memory-hotplug.txt for more information.
1407 If you are unsure how to answer this question, answer N.
1408
1409 config ARCH_PROC_KCORE_TEXT
1410 def_bool y
1411 depends on X86_64 && PROC_KCORE
1412
1413 config ILLEGAL_POINTER_VALUE
1414 hex
1415 default 0 if X86_32
1416 default 0xdead000000000000 if X86_64
1417
1418 source "mm/Kconfig"
1419
1420 config X86_PMEM_LEGACY
1421 bool "Support non-standard NVDIMMs and ADR protected memory"
1422 help
1423 Treat memory marked using the non-standard e820 type of 12 as used
1424 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1425 The kernel will offer these regions to the 'pmem' driver so
1426 they can be used for persistent storage.
1427
1428 Say Y if unsure.
1429
1430 config HIGHPTE
1431 bool "Allocate 3rd-level pagetables from highmem"
1432 depends on HIGHMEM
1433 ---help---
1434 The VM uses one page table entry for each page of physical memory.
1435 For systems with a lot of RAM, this can be wasteful of precious
1436 low memory. Setting this option will put user-space page table
1437 entries in high memory.
1438
1439 config X86_CHECK_BIOS_CORRUPTION
1440 bool "Check for low memory corruption"
1441 ---help---
1442 Periodically check for memory corruption in low memory, which
1443 is suspected to be caused by BIOS. Even when enabled in the
1444 configuration, it is disabled at runtime. Enable it by
1445 setting "memory_corruption_check=1" on the kernel command
1446 line. By default it scans the low 64k of memory every 60
1447 seconds; see the memory_corruption_check_size and
1448 memory_corruption_check_period parameters in
1449 Documentation/kernel-parameters.txt to adjust this.
1450
1451 When enabled with the default parameters, this option has
1452 almost no overhead, as it reserves a relatively small amount
1453 of memory and scans it infrequently. It both detects corruption
1454 and prevents it from affecting the running system.
1455
1456 It is, however, intended as a diagnostic tool; if repeatable
1457 BIOS-originated corruption always affects the same memory,
1458 you can use memmap= to prevent the kernel from using that
1459 memory.
1460
1461 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1462 bool "Set the default setting of memory_corruption_check"
1463 depends on X86_CHECK_BIOS_CORRUPTION
1464 default y
1465 ---help---
1466 Set whether the default state of memory_corruption_check is
1467 on or off.
1468
1469 config X86_RESERVE_LOW
1470 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1471 default 64
1472 range 4 640
1473 ---help---
1474 Specify the amount of low memory to reserve for the BIOS.
1475
1476 The first page contains BIOS data structures that the kernel
1477 must not use, so that page must always be reserved.
1478
1479 By default we reserve the first 64K of physical RAM, as a
1480 number of BIOSes are known to corrupt that memory range
1481 during events such as suspend/resume or monitor cable
1482 insertion, so it must not be used by the kernel.
1483
1484 You can set this to 4 if you are absolutely sure that you
1485 trust the BIOS to get all its memory reservations and usages
1486 right. If you know your BIOS have problems beyond the
1487 default 64K area, you can set this to 640 to avoid using the
1488 entire low memory range.
1489
1490 If you have doubts about the BIOS (e.g. suspend/resume does
1491 not work or there's kernel crashes after certain hardware
1492 hotplug events) then you might want to enable
1493 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1494 typical corruption patterns.
1495
1496 Leave this to the default value of 64 if you are unsure.
1497
1498 config MATH_EMULATION
1499 bool
1500 prompt "Math emulation" if X86_32
1501 ---help---
1502 Linux can emulate a math coprocessor (used for floating point
1503 operations) if you don't have one. 486DX and Pentium processors have
1504 a math coprocessor built in, 486SX and 386 do not, unless you added
1505 a 487DX or 387, respectively. (The messages during boot time can
1506 give you some hints here ["man dmesg"].) Everyone needs either a
1507 coprocessor or this emulation.
1508
1509 If you don't have a math coprocessor, you need to say Y here; if you
1510 say Y here even though you have a coprocessor, the coprocessor will
1511 be used nevertheless. (This behavior can be changed with the kernel
1512 command line option "no387", which comes handy if your coprocessor
1513 is broken. Try "man bootparam" or see the documentation of your boot
1514 loader (lilo or loadlin) about how to pass options to the kernel at
1515 boot time.) This means that it is a good idea to say Y here if you
1516 intend to use this kernel on different machines.
1517
1518 More information about the internals of the Linux math coprocessor
1519 emulation can be found in <file:arch/x86/math-emu/README>.
1520
1521 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1522 kernel, it won't hurt.
1523
1524 config MTRR
1525 def_bool y
1526 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1527 ---help---
1528 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1529 the Memory Type Range Registers (MTRRs) may be used to control
1530 processor access to memory ranges. This is most useful if you have
1531 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1532 allows bus write transfers to be combined into a larger transfer
1533 before bursting over the PCI/AGP bus. This can increase performance
1534 of image write operations 2.5 times or more. Saying Y here creates a
1535 /proc/mtrr file which may be used to manipulate your processor's
1536 MTRRs. Typically the X server should use this.
1537
1538 This code has a reasonably generic interface so that similar
1539 control registers on other processors can be easily supported
1540 as well:
1541
1542 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1543 Registers (ARRs) which provide a similar functionality to MTRRs. For
1544 these, the ARRs are used to emulate the MTRRs.
1545 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1546 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1547 write-combining. All of these processors are supported by this code
1548 and it makes sense to say Y here if you have one of them.
1549
1550 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1551 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1552 can lead to all sorts of problems, so it's good to say Y here.
1553
1554 You can safely say Y even if your machine doesn't have MTRRs, you'll
1555 just add about 9 KB to your kernel.
1556
1557 See <file:Documentation/x86/mtrr.txt> for more information.
1558
1559 config MTRR_SANITIZER
1560 def_bool y
1561 prompt "MTRR cleanup support"
1562 depends on MTRR
1563 ---help---
1564 Convert MTRR layout from continuous to discrete, so X drivers can
1565 add writeback entries.
1566
1567 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1568 The largest mtrr entry size for a continuous block can be set with
1569 mtrr_chunk_size.
1570
1571 If unsure, say Y.
1572
1573 config MTRR_SANITIZER_ENABLE_DEFAULT
1574 int "MTRR cleanup enable value (0-1)"
1575 range 0 1
1576 default "0"
1577 depends on MTRR_SANITIZER
1578 ---help---
1579 Enable mtrr cleanup default value
1580
1581 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1582 int "MTRR cleanup spare reg num (0-7)"
1583 range 0 7
1584 default "1"
1585 depends on MTRR_SANITIZER
1586 ---help---
1587 mtrr cleanup spare entries default, it can be changed via
1588 mtrr_spare_reg_nr=N on the kernel command line.
1589
1590 config X86_PAT
1591 def_bool y
1592 prompt "x86 PAT support" if EXPERT
1593 depends on MTRR
1594 ---help---
1595 Use PAT attributes to setup page level cache control.
1596
1597 PATs are the modern equivalents of MTRRs and are much more
1598 flexible than MTRRs.
1599
1600 Say N here if you see bootup problems (boot crash, boot hang,
1601 spontaneous reboots) or a non-working video driver.
1602
1603 If unsure, say Y.
1604
1605 config ARCH_USES_PG_UNCACHED
1606 def_bool y
1607 depends on X86_PAT
1608
1609 config ARCH_RANDOM
1610 def_bool y
1611 prompt "x86 architectural random number generator" if EXPERT
1612 ---help---
1613 Enable the x86 architectural RDRAND instruction
1614 (Intel Bull Mountain technology) to generate random numbers.
1615 If supported, this is a high bandwidth, cryptographically
1616 secure hardware random number generator.
1617
1618 config X86_SMAP
1619 def_bool y
1620 prompt "Supervisor Mode Access Prevention" if EXPERT
1621 ---help---
1622 Supervisor Mode Access Prevention (SMAP) is a security
1623 feature in newer Intel processors. There is a small
1624 performance cost if this enabled and turned on; there is
1625 also a small increase in the kernel size if this is enabled.
1626
1627 If unsure, say Y.
1628
1629 config X86_INTEL_MPX
1630 prompt "Intel MPX (Memory Protection Extensions)"
1631 def_bool n
1632 depends on CPU_SUP_INTEL
1633 ---help---
1634 MPX provides hardware features that can be used in
1635 conjunction with compiler-instrumented code to check
1636 memory references. It is designed to detect buffer
1637 overflow or underflow bugs.
1638
1639 This option enables running applications which are
1640 instrumented or otherwise use MPX. It does not use MPX
1641 itself inside the kernel or to protect the kernel
1642 against bad memory references.
1643
1644 Enabling this option will make the kernel larger:
1645 ~8k of kernel text and 36 bytes of data on a 64-bit
1646 defconfig. It adds a long to the 'mm_struct' which
1647 will increase the kernel memory overhead of each
1648 process and adds some branches to paths used during
1649 exec() and munmap().
1650
1651 For details, see Documentation/x86/intel_mpx.txt
1652
1653 If unsure, say N.
1654
1655 config EFI
1656 bool "EFI runtime service support"
1657 depends on ACPI
1658 select UCS2_STRING
1659 select EFI_RUNTIME_WRAPPERS
1660 ---help---
1661 This enables the kernel to use EFI runtime services that are
1662 available (such as the EFI variable services).
1663
1664 This option is only useful on systems that have EFI firmware.
1665 In addition, you should use the latest ELILO loader available
1666 at <http://elilo.sourceforge.net> in order to take advantage
1667 of EFI runtime services. However, even with this option, the
1668 resultant kernel should continue to boot on existing non-EFI
1669 platforms.
1670
1671 config EFI_STUB
1672 bool "EFI stub support"
1673 depends on EFI && !X86_USE_3DNOW
1674 select RELOCATABLE
1675 ---help---
1676 This kernel feature allows a bzImage to be loaded directly
1677 by EFI firmware without the use of a bootloader.
1678
1679 See Documentation/efi-stub.txt for more information.
1680
1681 config EFI_MIXED
1682 bool "EFI mixed-mode support"
1683 depends on EFI_STUB && X86_64
1684 ---help---
1685 Enabling this feature allows a 64-bit kernel to be booted
1686 on a 32-bit firmware, provided that your CPU supports 64-bit
1687 mode.
1688
1689 Note that it is not possible to boot a mixed-mode enabled
1690 kernel via the EFI boot stub - a bootloader that supports
1691 the EFI handover protocol must be used.
1692
1693 If unsure, say N.
1694
1695 config SECCOMP
1696 def_bool y
1697 prompt "Enable seccomp to safely compute untrusted bytecode"
1698 ---help---
1699 This kernel feature is useful for number crunching applications
1700 that may need to compute untrusted bytecode during their
1701 execution. By using pipes or other transports made available to
1702 the process as file descriptors supporting the read/write
1703 syscalls, it's possible to isolate those applications in
1704 their own address space using seccomp. Once seccomp is
1705 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1706 and the task is only allowed to execute a few safe syscalls
1707 defined by each seccomp mode.
1708
1709 If unsure, say Y. Only embedded should say N here.
1710
1711 source kernel/Kconfig.hz
1712
1713 config KEXEC
1714 bool "kexec system call"
1715 ---help---
1716 kexec is a system call that implements the ability to shutdown your
1717 current kernel, and to start another kernel. It is like a reboot
1718 but it is independent of the system firmware. And like a reboot
1719 you can start any kernel with it, not just Linux.
1720
1721 The name comes from the similarity to the exec system call.
1722
1723 It is an ongoing process to be certain the hardware in a machine
1724 is properly shutdown, so do not be surprised if this code does not
1725 initially work for you. As of this writing the exact hardware
1726 interface is strongly in flux, so no good recommendation can be
1727 made.
1728
1729 config KEXEC_FILE
1730 bool "kexec file based system call"
1731 select BUILD_BIN2C
1732 depends on KEXEC
1733 depends on X86_64
1734 depends on CRYPTO=y
1735 depends on CRYPTO_SHA256=y
1736 ---help---
1737 This is new version of kexec system call. This system call is
1738 file based and takes file descriptors as system call argument
1739 for kernel and initramfs as opposed to list of segments as
1740 accepted by previous system call.
1741
1742 config KEXEC_VERIFY_SIG
1743 bool "Verify kernel signature during kexec_file_load() syscall"
1744 depends on KEXEC_FILE
1745 ---help---
1746 This option makes kernel signature verification mandatory for
1747 the kexec_file_load() syscall.
1748
1749 In addition to that option, you need to enable signature
1750 verification for the corresponding kernel image type being
1751 loaded in order for this to work.
1752
1753 config KEXEC_BZIMAGE_VERIFY_SIG
1754 bool "Enable bzImage signature verification support"
1755 depends on KEXEC_VERIFY_SIG
1756 depends on SIGNED_PE_FILE_VERIFICATION
1757 select SYSTEM_TRUSTED_KEYRING
1758 ---help---
1759 Enable bzImage signature verification support.
1760
1761 config CRASH_DUMP
1762 bool "kernel crash dumps"
1763 depends on X86_64 || (X86_32 && HIGHMEM)
1764 ---help---
1765 Generate crash dump after being started by kexec.
1766 This should be normally only set in special crash dump kernels
1767 which are loaded in the main kernel with kexec-tools into
1768 a specially reserved region and then later executed after
1769 a crash by kdump/kexec. The crash dump kernel must be compiled
1770 to a memory address not used by the main kernel or BIOS using
1771 PHYSICAL_START, or it must be built as a relocatable image
1772 (CONFIG_RELOCATABLE=y).
1773 For more details see Documentation/kdump/kdump.txt
1774
1775 config KEXEC_JUMP
1776 bool "kexec jump"
1777 depends on KEXEC && HIBERNATION
1778 ---help---
1779 Jump between original kernel and kexeced kernel and invoke
1780 code in physical address mode via KEXEC
1781
1782 config PHYSICAL_START
1783 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1784 default "0x1000000"
1785 ---help---
1786 This gives the physical address where the kernel is loaded.
1787
1788 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1789 bzImage will decompress itself to above physical address and
1790 run from there. Otherwise, bzImage will run from the address where
1791 it has been loaded by the boot loader and will ignore above physical
1792 address.
1793
1794 In normal kdump cases one does not have to set/change this option
1795 as now bzImage can be compiled as a completely relocatable image
1796 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1797 address. This option is mainly useful for the folks who don't want
1798 to use a bzImage for capturing the crash dump and want to use a
1799 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1800 to be specifically compiled to run from a specific memory area
1801 (normally a reserved region) and this option comes handy.
1802
1803 So if you are using bzImage for capturing the crash dump,
1804 leave the value here unchanged to 0x1000000 and set
1805 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1806 for capturing the crash dump change this value to start of
1807 the reserved region. In other words, it can be set based on
1808 the "X" value as specified in the "crashkernel=YM@XM"
1809 command line boot parameter passed to the panic-ed
1810 kernel. Please take a look at Documentation/kdump/kdump.txt
1811 for more details about crash dumps.
1812
1813 Usage of bzImage for capturing the crash dump is recommended as
1814 one does not have to build two kernels. Same kernel can be used
1815 as production kernel and capture kernel. Above option should have
1816 gone away after relocatable bzImage support is introduced. But it
1817 is present because there are users out there who continue to use
1818 vmlinux for dump capture. This option should go away down the
1819 line.
1820
1821 Don't change this unless you know what you are doing.
1822
1823 config RELOCATABLE
1824 bool "Build a relocatable kernel"
1825 default y
1826 ---help---
1827 This builds a kernel image that retains relocation information
1828 so it can be loaded someplace besides the default 1MB.
1829 The relocations tend to make the kernel binary about 10% larger,
1830 but are discarded at runtime.
1831
1832 One use is for the kexec on panic case where the recovery kernel
1833 must live at a different physical address than the primary
1834 kernel.
1835
1836 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1837 it has been loaded at and the compile time physical address
1838 (CONFIG_PHYSICAL_START) is used as the minimum location.
1839
1840 config RANDOMIZE_BASE
1841 bool "Randomize the address of the kernel image"
1842 depends on RELOCATABLE
1843 default n
1844 ---help---
1845 Randomizes the physical and virtual address at which the
1846 kernel image is decompressed, as a security feature that
1847 deters exploit attempts relying on knowledge of the location
1848 of kernel internals.
1849
1850 Entropy is generated using the RDRAND instruction if it is
1851 supported. If RDTSC is supported, it is used as well. If
1852 neither RDRAND nor RDTSC are supported, then randomness is
1853 read from the i8254 timer.
1854
1855 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1856 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1857 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1858 minimum of 2MiB, only 10 bits of entropy is theoretically
1859 possible. At best, due to page table layouts, 64-bit can use
1860 9 bits of entropy and 32-bit uses 8 bits.
1861
1862 If unsure, say N.
1863
1864 config RANDOMIZE_BASE_MAX_OFFSET
1865 hex "Maximum kASLR offset allowed" if EXPERT
1866 depends on RANDOMIZE_BASE
1867 range 0x0 0x20000000 if X86_32
1868 default "0x20000000" if X86_32
1869 range 0x0 0x40000000 if X86_64
1870 default "0x40000000" if X86_64
1871 ---help---
1872 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1873 memory is used to determine the maximal offset in bytes that will
1874 be applied to the kernel when kernel Address Space Layout
1875 Randomization (kASLR) is active. This must be a multiple of
1876 PHYSICAL_ALIGN.
1877
1878 On 32-bit this is limited to 512MiB by page table layouts. The
1879 default is 512MiB.
1880
1881 On 64-bit this is limited by how the kernel fixmap page table is
1882 positioned, so this cannot be larger than 1GiB currently. Without
1883 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1884 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1885 modules area will shrink to compensate, up to the current maximum
1886 1GiB to 1GiB split. The default is 1GiB.
1887
1888 If unsure, leave at the default value.
1889
1890 # Relocation on x86 needs some additional build support
1891 config X86_NEED_RELOCS
1892 def_bool y
1893 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1894
1895 config PHYSICAL_ALIGN
1896 hex "Alignment value to which kernel should be aligned"
1897 default "0x200000"
1898 range 0x2000 0x1000000 if X86_32
1899 range 0x200000 0x1000000 if X86_64
1900 ---help---
1901 This value puts the alignment restrictions on physical address
1902 where kernel is loaded and run from. Kernel is compiled for an
1903 address which meets above alignment restriction.
1904
1905 If bootloader loads the kernel at a non-aligned address and
1906 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1907 address aligned to above value and run from there.
1908
1909 If bootloader loads the kernel at a non-aligned address and
1910 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1911 load address and decompress itself to the address it has been
1912 compiled for and run from there. The address for which kernel is
1913 compiled already meets above alignment restrictions. Hence the
1914 end result is that kernel runs from a physical address meeting
1915 above alignment restrictions.
1916
1917 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1918 this value must be a multiple of 0x200000.
1919
1920 Don't change this unless you know what you are doing.
1921
1922 config HOTPLUG_CPU
1923 bool "Support for hot-pluggable CPUs"
1924 depends on SMP
1925 ---help---
1926 Say Y here to allow turning CPUs off and on. CPUs can be
1927 controlled through /sys/devices/system/cpu.
1928 ( Note: power management support will enable this option
1929 automatically on SMP systems. )
1930 Say N if you want to disable CPU hotplug.
1931
1932 config BOOTPARAM_HOTPLUG_CPU0
1933 bool "Set default setting of cpu0_hotpluggable"
1934 default n
1935 depends on HOTPLUG_CPU
1936 ---help---
1937 Set whether default state of cpu0_hotpluggable is on or off.
1938
1939 Say Y here to enable CPU0 hotplug by default. If this switch
1940 is turned on, there is no need to give cpu0_hotplug kernel
1941 parameter and the CPU0 hotplug feature is enabled by default.
1942
1943 Please note: there are two known CPU0 dependencies if you want
1944 to enable the CPU0 hotplug feature either by this switch or by
1945 cpu0_hotplug kernel parameter.
1946
1947 First, resume from hibernate or suspend always starts from CPU0.
1948 So hibernate and suspend are prevented if CPU0 is offline.
1949
1950 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1951 offline if any interrupt can not migrate out of CPU0. There may
1952 be other CPU0 dependencies.
1953
1954 Please make sure the dependencies are under your control before
1955 you enable this feature.
1956
1957 Say N if you don't want to enable CPU0 hotplug feature by default.
1958 You still can enable the CPU0 hotplug feature at boot by kernel
1959 parameter cpu0_hotplug.
1960
1961 config DEBUG_HOTPLUG_CPU0
1962 def_bool n
1963 prompt "Debug CPU0 hotplug"
1964 depends on HOTPLUG_CPU
1965 ---help---
1966 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1967 soon as possible and boots up userspace with CPU0 offlined. User
1968 can online CPU0 back after boot time.
1969
1970 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1971 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1972 compilation or giving cpu0_hotplug kernel parameter at boot.
1973
1974 If unsure, say N.
1975
1976 config COMPAT_VDSO
1977 def_bool n
1978 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1979 depends on X86_32 || IA32_EMULATION
1980 ---help---
1981 Certain buggy versions of glibc will crash if they are
1982 presented with a 32-bit vDSO that is not mapped at the address
1983 indicated in its segment table.
1984
1985 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1986 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1987 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
1988 the only released version with the bug, but OpenSUSE 9
1989 contains a buggy "glibc 2.3.2".
1990
1991 The symptom of the bug is that everything crashes on startup, saying:
1992 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1993
1994 Saying Y here changes the default value of the vdso32 boot
1995 option from 1 to 0, which turns off the 32-bit vDSO entirely.
1996 This works around the glibc bug but hurts performance.
1997
1998 If unsure, say N: if you are compiling your own kernel, you
1999 are unlikely to be using a buggy version of glibc.
2000
2001 config CMDLINE_BOOL
2002 bool "Built-in kernel command line"
2003 ---help---
2004 Allow for specifying boot arguments to the kernel at
2005 build time. On some systems (e.g. embedded ones), it is
2006 necessary or convenient to provide some or all of the
2007 kernel boot arguments with the kernel itself (that is,
2008 to not rely on the boot loader to provide them.)
2009
2010 To compile command line arguments into the kernel,
2011 set this option to 'Y', then fill in the
2012 the boot arguments in CONFIG_CMDLINE.
2013
2014 Systems with fully functional boot loaders (i.e. non-embedded)
2015 should leave this option set to 'N'.
2016
2017 config CMDLINE
2018 string "Built-in kernel command string"
2019 depends on CMDLINE_BOOL
2020 default ""
2021 ---help---
2022 Enter arguments here that should be compiled into the kernel
2023 image and used at boot time. If the boot loader provides a
2024 command line at boot time, it is appended to this string to
2025 form the full kernel command line, when the system boots.
2026
2027 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2028 change this behavior.
2029
2030 In most cases, the command line (whether built-in or provided
2031 by the boot loader) should specify the device for the root
2032 file system.
2033
2034 config CMDLINE_OVERRIDE
2035 bool "Built-in command line overrides boot loader arguments"
2036 depends on CMDLINE_BOOL
2037 ---help---
2038 Set this option to 'Y' to have the kernel ignore the boot loader
2039 command line, and use ONLY the built-in command line.
2040
2041 This is used to work around broken boot loaders. This should
2042 be set to 'N' under normal conditions.
2043
2044 source "kernel/livepatch/Kconfig"
2045
2046 endmenu
2047
2048 config ARCH_ENABLE_MEMORY_HOTPLUG
2049 def_bool y
2050 depends on X86_64 || (X86_32 && HIGHMEM)
2051
2052 config ARCH_ENABLE_MEMORY_HOTREMOVE
2053 def_bool y
2054 depends on MEMORY_HOTPLUG
2055
2056 config USE_PERCPU_NUMA_NODE_ID
2057 def_bool y
2058 depends on NUMA
2059
2060 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2061 def_bool y
2062 depends on X86_64 || X86_PAE
2063
2064 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2065 def_bool y
2066 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2067
2068 menu "Power management and ACPI options"
2069
2070 config ARCH_HIBERNATION_HEADER
2071 def_bool y
2072 depends on X86_64 && HIBERNATION
2073
2074 source "kernel/power/Kconfig"
2075
2076 source "drivers/acpi/Kconfig"
2077
2078 source "drivers/sfi/Kconfig"
2079
2080 config X86_APM_BOOT
2081 def_bool y
2082 depends on APM
2083
2084 menuconfig APM
2085 tristate "APM (Advanced Power Management) BIOS support"
2086 depends on X86_32 && PM_SLEEP
2087 ---help---
2088 APM is a BIOS specification for saving power using several different
2089 techniques. This is mostly useful for battery powered laptops with
2090 APM compliant BIOSes. If you say Y here, the system time will be
2091 reset after a RESUME operation, the /proc/apm device will provide
2092 battery status information, and user-space programs will receive
2093 notification of APM "events" (e.g. battery status change).
2094
2095 If you select "Y" here, you can disable actual use of the APM
2096 BIOS by passing the "apm=off" option to the kernel at boot time.
2097
2098 Note that the APM support is almost completely disabled for
2099 machines with more than one CPU.
2100
2101 In order to use APM, you will need supporting software. For location
2102 and more information, read <file:Documentation/power/apm-acpi.txt>
2103 and the Battery Powered Linux mini-HOWTO, available from
2104 <http://www.tldp.org/docs.html#howto>.
2105
2106 This driver does not spin down disk drives (see the hdparm(8)
2107 manpage ("man 8 hdparm") for that), and it doesn't turn off
2108 VESA-compliant "green" monitors.
2109
2110 This driver does not support the TI 4000M TravelMate and the ACER
2111 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2112 desktop machines also don't have compliant BIOSes, and this driver
2113 may cause those machines to panic during the boot phase.
2114
2115 Generally, if you don't have a battery in your machine, there isn't
2116 much point in using this driver and you should say N. If you get
2117 random kernel OOPSes or reboots that don't seem to be related to
2118 anything, try disabling/enabling this option (or disabling/enabling
2119 APM in your BIOS).
2120
2121 Some other things you should try when experiencing seemingly random,
2122 "weird" problems:
2123
2124 1) make sure that you have enough swap space and that it is
2125 enabled.
2126 2) pass the "no-hlt" option to the kernel
2127 3) switch on floating point emulation in the kernel and pass
2128 the "no387" option to the kernel
2129 4) pass the "floppy=nodma" option to the kernel
2130 5) pass the "mem=4M" option to the kernel (thereby disabling
2131 all but the first 4 MB of RAM)
2132 6) make sure that the CPU is not over clocked.
2133 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2134 8) disable the cache from your BIOS settings
2135 9) install a fan for the video card or exchange video RAM
2136 10) install a better fan for the CPU
2137 11) exchange RAM chips
2138 12) exchange the motherboard.
2139
2140 To compile this driver as a module, choose M here: the
2141 module will be called apm.
2142
2143 if APM
2144
2145 config APM_IGNORE_USER_SUSPEND
2146 bool "Ignore USER SUSPEND"
2147 ---help---
2148 This option will ignore USER SUSPEND requests. On machines with a
2149 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2150 series notebooks, it is necessary to say Y because of a BIOS bug.
2151
2152 config APM_DO_ENABLE
2153 bool "Enable PM at boot time"
2154 ---help---
2155 Enable APM features at boot time. From page 36 of the APM BIOS
2156 specification: "When disabled, the APM BIOS does not automatically
2157 power manage devices, enter the Standby State, enter the Suspend
2158 State, or take power saving steps in response to CPU Idle calls."
2159 This driver will make CPU Idle calls when Linux is idle (unless this
2160 feature is turned off -- see "Do CPU IDLE calls", below). This
2161 should always save battery power, but more complicated APM features
2162 will be dependent on your BIOS implementation. You may need to turn
2163 this option off if your computer hangs at boot time when using APM
2164 support, or if it beeps continuously instead of suspending. Turn
2165 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2166 T400CDT. This is off by default since most machines do fine without
2167 this feature.
2168
2169 config APM_CPU_IDLE
2170 depends on CPU_IDLE
2171 bool "Make CPU Idle calls when idle"
2172 ---help---
2173 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2174 On some machines, this can activate improved power savings, such as
2175 a slowed CPU clock rate, when the machine is idle. These idle calls
2176 are made after the idle loop has run for some length of time (e.g.,
2177 333 mS). On some machines, this will cause a hang at boot time or
2178 whenever the CPU becomes idle. (On machines with more than one CPU,
2179 this option does nothing.)
2180
2181 config APM_DISPLAY_BLANK
2182 bool "Enable console blanking using APM"
2183 ---help---
2184 Enable console blanking using the APM. Some laptops can use this to
2185 turn off the LCD backlight when the screen blanker of the Linux
2186 virtual console blanks the screen. Note that this is only used by
2187 the virtual console screen blanker, and won't turn off the backlight
2188 when using the X Window system. This also doesn't have anything to
2189 do with your VESA-compliant power-saving monitor. Further, this
2190 option doesn't work for all laptops -- it might not turn off your
2191 backlight at all, or it might print a lot of errors to the console,
2192 especially if you are using gpm.
2193
2194 config APM_ALLOW_INTS
2195 bool "Allow interrupts during APM BIOS calls"
2196 ---help---
2197 Normally we disable external interrupts while we are making calls to
2198 the APM BIOS as a measure to lessen the effects of a badly behaving
2199 BIOS implementation. The BIOS should reenable interrupts if it
2200 needs to. Unfortunately, some BIOSes do not -- especially those in
2201 many of the newer IBM Thinkpads. If you experience hangs when you
2202 suspend, try setting this to Y. Otherwise, say N.
2203
2204 endif # APM
2205
2206 source "drivers/cpufreq/Kconfig"
2207
2208 source "drivers/cpuidle/Kconfig"
2209
2210 source "drivers/idle/Kconfig"
2211
2212 endmenu
2213
2214
2215 menu "Bus options (PCI etc.)"
2216
2217 config PCI
2218 bool "PCI support"
2219 default y
2220 ---help---
2221 Find out whether you have a PCI motherboard. PCI is the name of a
2222 bus system, i.e. the way the CPU talks to the other stuff inside
2223 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2224 VESA. If you have PCI, say Y, otherwise N.
2225
2226 choice
2227 prompt "PCI access mode"
2228 depends on X86_32 && PCI
2229 default PCI_GOANY
2230 ---help---
2231 On PCI systems, the BIOS can be used to detect the PCI devices and
2232 determine their configuration. However, some old PCI motherboards
2233 have BIOS bugs and may crash if this is done. Also, some embedded
2234 PCI-based systems don't have any BIOS at all. Linux can also try to
2235 detect the PCI hardware directly without using the BIOS.
2236
2237 With this option, you can specify how Linux should detect the
2238 PCI devices. If you choose "BIOS", the BIOS will be used,
2239 if you choose "Direct", the BIOS won't be used, and if you
2240 choose "MMConfig", then PCI Express MMCONFIG will be used.
2241 If you choose "Any", the kernel will try MMCONFIG, then the
2242 direct access method and falls back to the BIOS if that doesn't
2243 work. If unsure, go with the default, which is "Any".
2244
2245 config PCI_GOBIOS
2246 bool "BIOS"
2247
2248 config PCI_GOMMCONFIG
2249 bool "MMConfig"
2250
2251 config PCI_GODIRECT
2252 bool "Direct"
2253
2254 config PCI_GOOLPC
2255 bool "OLPC XO-1"
2256 depends on OLPC
2257
2258 config PCI_GOANY
2259 bool "Any"
2260
2261 endchoice
2262
2263 config PCI_BIOS
2264 def_bool y
2265 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2266
2267 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2268 config PCI_DIRECT
2269 def_bool y
2270 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2271
2272 config PCI_MMCONFIG
2273 def_bool y
2274 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2275
2276 config PCI_OLPC
2277 def_bool y
2278 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2279
2280 config PCI_XEN
2281 def_bool y
2282 depends on PCI && XEN
2283 select SWIOTLB_XEN
2284
2285 config PCI_DOMAINS
2286 def_bool y
2287 depends on PCI
2288
2289 config PCI_MMCONFIG
2290 bool "Support mmconfig PCI config space access"
2291 depends on X86_64 && PCI && ACPI
2292
2293 config PCI_CNB20LE_QUIRK
2294 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2295 depends on PCI
2296 help
2297 Read the PCI windows out of the CNB20LE host bridge. This allows
2298 PCI hotplug to work on systems with the CNB20LE chipset which do
2299 not have ACPI.
2300
2301 There's no public spec for this chipset, and this functionality
2302 is known to be incomplete.
2303
2304 You should say N unless you know you need this.
2305
2306 source "drivers/pci/pcie/Kconfig"
2307
2308 source "drivers/pci/Kconfig"
2309
2310 # x86_64 have no ISA slots, but can have ISA-style DMA.
2311 config ISA_DMA_API
2312 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2313 default y
2314 help
2315 Enables ISA-style DMA support for devices requiring such controllers.
2316 If unsure, say Y.
2317
2318 if X86_32
2319
2320 config ISA
2321 bool "ISA support"
2322 ---help---
2323 Find out whether you have ISA slots on your motherboard. ISA is the
2324 name of a bus system, i.e. the way the CPU talks to the other stuff
2325 inside your box. Other bus systems are PCI, EISA, MicroChannel
2326 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2327 newer boards don't support it. If you have ISA, say Y, otherwise N.
2328
2329 config EISA
2330 bool "EISA support"
2331 depends on ISA
2332 ---help---
2333 The Extended Industry Standard Architecture (EISA) bus was
2334 developed as an open alternative to the IBM MicroChannel bus.
2335
2336 The EISA bus provided some of the features of the IBM MicroChannel
2337 bus while maintaining backward compatibility with cards made for
2338 the older ISA bus. The EISA bus saw limited use between 1988 and
2339 1995 when it was made obsolete by the PCI bus.
2340
2341 Say Y here if you are building a kernel for an EISA-based machine.
2342
2343 Otherwise, say N.
2344
2345 source "drivers/eisa/Kconfig"
2346
2347 config SCx200
2348 tristate "NatSemi SCx200 support"
2349 ---help---
2350 This provides basic support for National Semiconductor's
2351 (now AMD's) Geode processors. The driver probes for the
2352 PCI-IDs of several on-chip devices, so its a good dependency
2353 for other scx200_* drivers.
2354
2355 If compiled as a module, the driver is named scx200.
2356
2357 config SCx200HR_TIMER
2358 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2359 depends on SCx200
2360 default y
2361 ---help---
2362 This driver provides a clocksource built upon the on-chip
2363 27MHz high-resolution timer. Its also a workaround for
2364 NSC Geode SC-1100's buggy TSC, which loses time when the
2365 processor goes idle (as is done by the scheduler). The
2366 other workaround is idle=poll boot option.
2367
2368 config OLPC
2369 bool "One Laptop Per Child support"
2370 depends on !X86_PAE
2371 select GPIOLIB
2372 select OF
2373 select OF_PROMTREE
2374 select IRQ_DOMAIN
2375 ---help---
2376 Add support for detecting the unique features of the OLPC
2377 XO hardware.
2378
2379 config OLPC_XO1_PM
2380 bool "OLPC XO-1 Power Management"
2381 depends on OLPC && MFD_CS5535 && PM_SLEEP
2382 select MFD_CORE
2383 ---help---
2384 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2385
2386 config OLPC_XO1_RTC
2387 bool "OLPC XO-1 Real Time Clock"
2388 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2389 ---help---
2390 Add support for the XO-1 real time clock, which can be used as a
2391 programmable wakeup source.
2392
2393 config OLPC_XO1_SCI
2394 bool "OLPC XO-1 SCI extras"
2395 depends on OLPC && OLPC_XO1_PM
2396 depends on INPUT=y
2397 select POWER_SUPPLY
2398 select GPIO_CS5535
2399 select MFD_CORE
2400 ---help---
2401 Add support for SCI-based features of the OLPC XO-1 laptop:
2402 - EC-driven system wakeups
2403 - Power button
2404 - Ebook switch
2405 - Lid switch
2406 - AC adapter status updates
2407 - Battery status updates
2408
2409 config OLPC_XO15_SCI
2410 bool "OLPC XO-1.5 SCI extras"
2411 depends on OLPC && ACPI
2412 select POWER_SUPPLY
2413 ---help---
2414 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2415 - EC-driven system wakeups
2416 - AC adapter status updates
2417 - Battery status updates
2418
2419 config ALIX
2420 bool "PCEngines ALIX System Support (LED setup)"
2421 select GPIOLIB
2422 ---help---
2423 This option enables system support for the PCEngines ALIX.
2424 At present this just sets up LEDs for GPIO control on
2425 ALIX2/3/6 boards. However, other system specific setup should
2426 get added here.
2427
2428 Note: You must still enable the drivers for GPIO and LED support
2429 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2430
2431 Note: You have to set alix.force=1 for boards with Award BIOS.
2432
2433 config NET5501
2434 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2435 select GPIOLIB
2436 ---help---
2437 This option enables system support for the Soekris Engineering net5501.
2438
2439 config GEOS
2440 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2441 select GPIOLIB
2442 depends on DMI
2443 ---help---
2444 This option enables system support for the Traverse Technologies GEOS.
2445
2446 config TS5500
2447 bool "Technologic Systems TS-5500 platform support"
2448 depends on MELAN
2449 select CHECK_SIGNATURE
2450 select NEW_LEDS
2451 select LEDS_CLASS
2452 ---help---
2453 This option enables system support for the Technologic Systems TS-5500.
2454
2455 endif # X86_32
2456
2457 config AMD_NB
2458 def_bool y
2459 depends on CPU_SUP_AMD && PCI
2460
2461 source "drivers/pcmcia/Kconfig"
2462
2463 source "drivers/pci/hotplug/Kconfig"
2464
2465 config RAPIDIO
2466 tristate "RapidIO support"
2467 depends on PCI
2468 default n
2469 help
2470 If enabled this option will include drivers and the core
2471 infrastructure code to support RapidIO interconnect devices.
2472
2473 source "drivers/rapidio/Kconfig"
2474
2475 config X86_SYSFB
2476 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2477 help
2478 Firmwares often provide initial graphics framebuffers so the BIOS,
2479 bootloader or kernel can show basic video-output during boot for
2480 user-guidance and debugging. Historically, x86 used the VESA BIOS
2481 Extensions and EFI-framebuffers for this, which are mostly limited
2482 to x86.
2483 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2484 framebuffers so the new generic system-framebuffer drivers can be
2485 used on x86. If the framebuffer is not compatible with the generic
2486 modes, it is adverticed as fallback platform framebuffer so legacy
2487 drivers like efifb, vesafb and uvesafb can pick it up.
2488 If this option is not selected, all system framebuffers are always
2489 marked as fallback platform framebuffers as usual.
2490
2491 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2492 not be able to pick up generic system framebuffers if this option
2493 is selected. You are highly encouraged to enable simplefb as
2494 replacement if you select this option. simplefb can correctly deal
2495 with generic system framebuffers. But you should still keep vesafb
2496 and others enabled as fallback if a system framebuffer is
2497 incompatible with simplefb.
2498
2499 If unsure, say Y.
2500
2501 endmenu
2502
2503
2504 menu "Executable file formats / Emulations"
2505
2506 source "fs/Kconfig.binfmt"
2507
2508 config IA32_EMULATION
2509 bool "IA32 Emulation"
2510 depends on X86_64
2511 select BINFMT_ELF
2512 select COMPAT_BINFMT_ELF
2513 select HAVE_UID16
2514 ---help---
2515 Include code to run legacy 32-bit programs under a
2516 64-bit kernel. You should likely turn this on, unless you're
2517 100% sure that you don't have any 32-bit programs left.
2518
2519 config IA32_AOUT
2520 tristate "IA32 a.out support"
2521 depends on IA32_EMULATION
2522 ---help---
2523 Support old a.out binaries in the 32bit emulation.
2524
2525 config X86_X32
2526 bool "x32 ABI for 64-bit mode"
2527 depends on X86_64 && IA32_EMULATION
2528 ---help---
2529 Include code to run binaries for the x32 native 32-bit ABI
2530 for 64-bit processors. An x32 process gets access to the
2531 full 64-bit register file and wide data path while leaving
2532 pointers at 32 bits for smaller memory footprint.
2533
2534 You will need a recent binutils (2.22 or later) with
2535 elf32_x86_64 support enabled to compile a kernel with this
2536 option set.
2537
2538 config COMPAT
2539 def_bool y
2540 depends on IA32_EMULATION || X86_X32
2541 select ARCH_WANT_OLD_COMPAT_IPC
2542
2543 if COMPAT
2544 config COMPAT_FOR_U64_ALIGNMENT
2545 def_bool y
2546
2547 config SYSVIPC_COMPAT
2548 def_bool y
2549 depends on SYSVIPC
2550
2551 config KEYS_COMPAT
2552 def_bool y
2553 depends on KEYS
2554 endif
2555
2556 endmenu
2557
2558
2559 config HAVE_ATOMIC_IOMAP
2560 def_bool y
2561 depends on X86_32
2562
2563 config X86_DEV_DMA_OPS
2564 bool
2565 depends on X86_64 || STA2X11
2566
2567 config X86_DMA_REMAP
2568 bool
2569 depends on STA2X11
2570
2571 config PMC_ATOM
2572 def_bool y
2573 depends on PCI
2574
2575 source "net/Kconfig"
2576
2577 source "drivers/Kconfig"
2578
2579 source "drivers/firmware/Kconfig"
2580
2581 source "fs/Kconfig"
2582
2583 source "arch/x86/Kconfig.debug"
2584
2585 source "security/Kconfig"
2586
2587 source "crypto/Kconfig"
2588
2589 source "arch/x86/kvm/Kconfig"
2590
2591 source "lib/Kconfig"