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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_PMEM_API
31 select ARCH_HAS_SG_CHAIN
32 select ARCH_HAVE_NMI_SAFE_CMPXCHG
33 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
34 select ARCH_MIGHT_HAVE_PC_PARPORT
35 select ARCH_MIGHT_HAVE_PC_SERIO
36 select ARCH_SUPPORTS_ATOMIC_RMW
37 select ARCH_SUPPORTS_INT128 if X86_64
38 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
39 select ARCH_USE_BUILTIN_BSWAP
40 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
41 select ARCH_USE_QUEUED_RWLOCKS
42 select ARCH_USE_QUEUED_SPINLOCKS
43 select ARCH_WANT_FRAME_POINTERS
44 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
45 select ARCH_WANT_OPTIONAL_GPIOLIB
46 select BUILDTIME_EXTABLE_SORT
47 select CLKEVT_I8253
48 select CLKSRC_I8253 if X86_32
49 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
50 select CLOCKSOURCE_WATCHDOG
51 select CLONE_BACKWARDS if X86_32
52 select COMPAT_OLD_SIGACTION if IA32_EMULATION
53 select DCACHE_WORD_ACCESS
54 select EDAC_ATOMIC_SCRUB
55 select EDAC_SUPPORT
56 select GENERIC_CLOCKEVENTS
57 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
58 select GENERIC_CLOCKEVENTS_MIN_ADJUST
59 select GENERIC_CMOS_UPDATE
60 select GENERIC_CPU_AUTOPROBE
61 select GENERIC_EARLY_IOREMAP
62 select GENERIC_FIND_FIRST_BIT
63 select GENERIC_IOMAP
64 select GENERIC_IRQ_PROBE
65 select GENERIC_IRQ_SHOW
66 select GENERIC_PENDING_IRQ if SMP
67 select GENERIC_SMP_IDLE_THREAD
68 select GENERIC_STRNCPY_FROM_USER
69 select GENERIC_STRNLEN_USER
70 select GENERIC_TIME_VSYSCALL
71 select HAVE_ACPI_APEI if ACPI
72 select HAVE_ACPI_APEI_NMI if ACPI
73 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
74 select HAVE_AOUT if X86_32
75 select HAVE_ARCH_AUDITSYSCALL
76 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
77 select HAVE_ARCH_JUMP_LABEL
78 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
79 select HAVE_ARCH_KGDB
80 select HAVE_ARCH_KMEMCHECK
81 select HAVE_ARCH_SECCOMP_FILTER
82 select HAVE_ARCH_SOFT_DIRTY if X86_64
83 select HAVE_ARCH_TRACEHOOK
84 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
85 select HAVE_BPF_JIT if X86_64
86 select HAVE_CC_STACKPROTECTOR
87 select HAVE_CMPXCHG_DOUBLE
88 select HAVE_CMPXCHG_LOCAL
89 select HAVE_CONTEXT_TRACKING if X86_64
90 select HAVE_C_RECORDMCOUNT
91 select HAVE_DEBUG_KMEMLEAK
92 select HAVE_DEBUG_STACKOVERFLOW
93 select HAVE_DMA_API_DEBUG
94 select HAVE_DMA_ATTRS
95 select HAVE_DMA_CONTIGUOUS
96 select HAVE_DYNAMIC_FTRACE
97 select HAVE_DYNAMIC_FTRACE_WITH_REGS
98 select HAVE_EFFICIENT_UNALIGNED_ACCESS
99 select HAVE_FENTRY if X86_64
100 select HAVE_FTRACE_MCOUNT_RECORD
101 select HAVE_FUNCTION_GRAPH_FP_TEST
102 select HAVE_FUNCTION_GRAPH_TRACER
103 select HAVE_FUNCTION_TRACER
104 select HAVE_GENERIC_DMA_COHERENT if X86_32
105 select HAVE_HW_BREAKPOINT
106 select HAVE_IDE
107 select HAVE_IOREMAP_PROT
108 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
109 select HAVE_IRQ_TIME_ACCOUNTING
110 select HAVE_KERNEL_BZIP2
111 select HAVE_KERNEL_GZIP
112 select HAVE_KERNEL_LZ4
113 select HAVE_KERNEL_LZMA
114 select HAVE_KERNEL_LZO
115 select HAVE_KERNEL_XZ
116 select HAVE_KPROBES
117 select HAVE_KPROBES_ON_FTRACE
118 select HAVE_KRETPROBES
119 select HAVE_KVM
120 select HAVE_LIVEPATCH if X86_64
121 select HAVE_MEMBLOCK
122 select HAVE_MEMBLOCK_NODE_MAP
123 select HAVE_MIXED_BREAKPOINTS_REGS
124 select HAVE_OPROFILE
125 select HAVE_OPTPROBES
126 select HAVE_PCSPKR_PLATFORM
127 select HAVE_PERF_EVENTS
128 select HAVE_PERF_EVENTS_NMI
129 select HAVE_PERF_REGS
130 select HAVE_PERF_USER_STACK_DUMP
131 select HAVE_REGS_AND_STACK_ACCESS_API
132 select HAVE_SYSCALL_TRACEPOINTS
133 select HAVE_UID16 if X86_32
134 select HAVE_UNSTABLE_SCHED_CLOCK
135 select HAVE_USER_RETURN_NOTIFIER
136 select IRQ_FORCED_THREADING
137 select MODULES_USE_ELF_RELA if X86_64
138 select MODULES_USE_ELF_REL if X86_32
139 select OLD_SIGACTION if X86_32
140 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
141 select PERF_EVENTS
142 select RTC_LIB
143 select SPARSE_IRQ
144 select SRCU
145 select SYSCTL_EXCEPTION_TRACE
146 select USER_STACKTRACE_SUPPORT
147 select VIRT_TO_BUS
148 select X86_DEV_DMA_OPS if X86_64
149 select X86_FEATURE_NAMES if PROC_FS
150
151 config INSTRUCTION_DECODER
152 def_bool y
153 depends on KPROBES || PERF_EVENTS || UPROBES
154
155 config PERF_EVENTS_INTEL_UNCORE
156 def_bool y
157 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
158
159 config OUTPUT_FORMAT
160 string
161 default "elf32-i386" if X86_32
162 default "elf64-x86-64" if X86_64
163
164 config ARCH_DEFCONFIG
165 string
166 default "arch/x86/configs/i386_defconfig" if X86_32
167 default "arch/x86/configs/x86_64_defconfig" if X86_64
168
169 config LOCKDEP_SUPPORT
170 def_bool y
171
172 config STACKTRACE_SUPPORT
173 def_bool y
174
175 config HAVE_LATENCYTOP_SUPPORT
176 def_bool y
177
178 config MMU
179 def_bool y
180
181 config SBUS
182 bool
183
184 config NEED_DMA_MAP_STATE
185 def_bool y
186 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
187
188 config NEED_SG_DMA_LENGTH
189 def_bool y
190
191 config GENERIC_ISA_DMA
192 def_bool y
193 depends on ISA_DMA_API
194
195 config GENERIC_BUG
196 def_bool y
197 depends on BUG
198 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
199
200 config GENERIC_BUG_RELATIVE_POINTERS
201 bool
202
203 config GENERIC_HWEIGHT
204 def_bool y
205
206 config ARCH_MAY_HAVE_PC_FDC
207 def_bool y
208 depends on ISA_DMA_API
209
210 config RWSEM_XCHGADD_ALGORITHM
211 def_bool y
212
213 config GENERIC_CALIBRATE_DELAY
214 def_bool y
215
216 config ARCH_HAS_CPU_RELAX
217 def_bool y
218
219 config ARCH_HAS_CACHE_LINE_SIZE
220 def_bool y
221
222 config HAVE_SETUP_PER_CPU_AREA
223 def_bool y
224
225 config NEED_PER_CPU_EMBED_FIRST_CHUNK
226 def_bool y
227
228 config NEED_PER_CPU_PAGE_FIRST_CHUNK
229 def_bool y
230
231 config ARCH_HIBERNATION_POSSIBLE
232 def_bool y
233
234 config ARCH_SUSPEND_POSSIBLE
235 def_bool y
236
237 config ARCH_WANT_HUGE_PMD_SHARE
238 def_bool y
239
240 config ARCH_WANT_GENERAL_HUGETLB
241 def_bool y
242
243 config ZONE_DMA32
244 def_bool y if X86_64
245
246 config AUDIT_ARCH
247 def_bool y if X86_64
248
249 config ARCH_SUPPORTS_OPTIMIZED_INLINING
250 def_bool y
251
252 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
253 def_bool y
254
255 config HAVE_INTEL_TXT
256 def_bool y
257 depends on INTEL_IOMMU && ACPI
258
259 config X86_32_SMP
260 def_bool y
261 depends on X86_32 && SMP
262
263 config X86_64_SMP
264 def_bool y
265 depends on X86_64 && SMP
266
267 config X86_32_LAZY_GS
268 def_bool y
269 depends on X86_32 && !CC_STACKPROTECTOR
270
271 config ARCH_HWEIGHT_CFLAGS
272 string
273 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
274 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
275
276 config ARCH_SUPPORTS_UPROBES
277 def_bool y
278
279 config FIX_EARLYCON_MEM
280 def_bool y
281
282 config PGTABLE_LEVELS
283 int
284 default 4 if X86_64
285 default 3 if X86_PAE
286 default 2
287
288 source "init/Kconfig"
289 source "kernel/Kconfig.freezer"
290
291 menu "Processor type and features"
292
293 config ZONE_DMA
294 bool "DMA memory allocation support" if EXPERT
295 default y
296 help
297 DMA memory allocation support allows devices with less than 32-bit
298 addressing to allocate within the first 16MB of address space.
299 Disable if no such devices will be used.
300
301 If unsure, say Y.
302
303 config SMP
304 bool "Symmetric multi-processing support"
305 ---help---
306 This enables support for systems with more than one CPU. If you have
307 a system with only one CPU, say N. If you have a system with more
308 than one CPU, say Y.
309
310 If you say N here, the kernel will run on uni- and multiprocessor
311 machines, but will use only one CPU of a multiprocessor machine. If
312 you say Y here, the kernel will run on many, but not all,
313 uniprocessor machines. On a uniprocessor machine, the kernel
314 will run faster if you say N here.
315
316 Note that if you say Y here and choose architecture "586" or
317 "Pentium" under "Processor family", the kernel will not work on 486
318 architectures. Similarly, multiprocessor kernels for the "PPro"
319 architecture may not work on all Pentium based boards.
320
321 People using multiprocessor machines who say Y here should also say
322 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
323 Management" code will be disabled if you say Y here.
324
325 See also <file:Documentation/x86/i386/IO-APIC.txt>,
326 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
327 <http://www.tldp.org/docs.html#howto>.
328
329 If you don't know what to do here, say N.
330
331 config X86_FEATURE_NAMES
332 bool "Processor feature human-readable names" if EMBEDDED
333 default y
334 ---help---
335 This option compiles in a table of x86 feature bits and corresponding
336 names. This is required to support /proc/cpuinfo and a few kernel
337 messages. You can disable this to save space, at the expense of
338 making those few kernel messages show numeric feature bits instead.
339
340 If in doubt, say Y.
341
342 config X86_X2APIC
343 bool "Support x2apic"
344 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
345 ---help---
346 This enables x2apic support on CPUs that have this feature.
347
348 This allows 32-bit apic IDs (so it can support very large systems),
349 and accesses the local apic via MSRs not via mmio.
350
351 If you don't know what to do here, say N.
352
353 config X86_MPPARSE
354 bool "Enable MPS table" if ACPI || SFI
355 default y
356 depends on X86_LOCAL_APIC
357 ---help---
358 For old smp systems that do not have proper acpi support. Newer systems
359 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
360
361 config X86_BIGSMP
362 bool "Support for big SMP systems with more than 8 CPUs"
363 depends on X86_32 && SMP
364 ---help---
365 This option is needed for the systems that have more than 8 CPUs
366
367 config GOLDFISH
368 def_bool y
369 depends on X86_GOLDFISH
370
371 if X86_32
372 config X86_EXTENDED_PLATFORM
373 bool "Support for extended (non-PC) x86 platforms"
374 default y
375 ---help---
376 If you disable this option then the kernel will only support
377 standard PC platforms. (which covers the vast majority of
378 systems out there.)
379
380 If you enable this option then you'll be able to select support
381 for the following (non-PC) 32 bit x86 platforms:
382 Goldfish (Android emulator)
383 AMD Elan
384 RDC R-321x SoC
385 SGI 320/540 (Visual Workstation)
386 STA2X11-based (e.g. Northville)
387 Moorestown MID devices
388
389 If you have one of these systems, or if you want to build a
390 generic distribution kernel, say Y here - otherwise say N.
391 endif
392
393 if X86_64
394 config X86_EXTENDED_PLATFORM
395 bool "Support for extended (non-PC) x86 platforms"
396 default y
397 ---help---
398 If you disable this option then the kernel will only support
399 standard PC platforms. (which covers the vast majority of
400 systems out there.)
401
402 If you enable this option then you'll be able to select support
403 for the following (non-PC) 64 bit x86 platforms:
404 Numascale NumaChip
405 ScaleMP vSMP
406 SGI Ultraviolet
407
408 If you have one of these systems, or if you want to build a
409 generic distribution kernel, say Y here - otherwise say N.
410 endif
411 # This is an alphabetically sorted list of 64 bit extended platforms
412 # Please maintain the alphabetic order if and when there are additions
413 config X86_NUMACHIP
414 bool "Numascale NumaChip"
415 depends on X86_64
416 depends on X86_EXTENDED_PLATFORM
417 depends on NUMA
418 depends on SMP
419 depends on X86_X2APIC
420 depends on PCI_MMCONFIG
421 ---help---
422 Adds support for Numascale NumaChip large-SMP systems. Needed to
423 enable more than ~168 cores.
424 If you don't have one of these, you should say N here.
425
426 config X86_VSMP
427 bool "ScaleMP vSMP"
428 select HYPERVISOR_GUEST
429 select PARAVIRT
430 depends on X86_64 && PCI
431 depends on X86_EXTENDED_PLATFORM
432 depends on SMP
433 ---help---
434 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
435 supposed to run on these EM64T-based machines. Only choose this option
436 if you have one of these machines.
437
438 config X86_UV
439 bool "SGI Ultraviolet"
440 depends on X86_64
441 depends on X86_EXTENDED_PLATFORM
442 depends on NUMA
443 depends on X86_X2APIC
444 depends on PCI
445 ---help---
446 This option is needed in order to support SGI Ultraviolet systems.
447 If you don't have one of these, you should say N here.
448
449 # Following is an alphabetically sorted list of 32 bit extended platforms
450 # Please maintain the alphabetic order if and when there are additions
451
452 config X86_GOLDFISH
453 bool "Goldfish (Virtual Platform)"
454 depends on X86_EXTENDED_PLATFORM
455 ---help---
456 Enable support for the Goldfish virtual platform used primarily
457 for Android development. Unless you are building for the Android
458 Goldfish emulator say N here.
459
460 config X86_INTEL_CE
461 bool "CE4100 TV platform"
462 depends on PCI
463 depends on PCI_GODIRECT
464 depends on X86_IO_APIC
465 depends on X86_32
466 depends on X86_EXTENDED_PLATFORM
467 select X86_REBOOTFIXUPS
468 select OF
469 select OF_EARLY_FLATTREE
470 ---help---
471 Select for the Intel CE media processor (CE4100) SOC.
472 This option compiles in support for the CE4100 SOC for settop
473 boxes and media devices.
474
475 config X86_INTEL_MID
476 bool "Intel MID platform support"
477 depends on X86_32
478 depends on X86_EXTENDED_PLATFORM
479 depends on X86_PLATFORM_DEVICES
480 depends on PCI
481 depends on PCI_GOANY
482 depends on X86_IO_APIC
483 select SFI
484 select I2C
485 select DW_APB_TIMER
486 select APB_TIMER
487 select INTEL_SCU_IPC
488 select MFD_INTEL_MSIC
489 ---help---
490 Select to build a kernel capable of supporting Intel MID (Mobile
491 Internet Device) platform systems which do not have the PCI legacy
492 interfaces. If you are building for a PC class system say N here.
493
494 Intel MID platforms are based on an Intel processor and chipset which
495 consume less power than most of the x86 derivatives.
496
497 config X86_INTEL_QUARK
498 bool "Intel Quark platform support"
499 depends on X86_32
500 depends on X86_EXTENDED_PLATFORM
501 depends on X86_PLATFORM_DEVICES
502 depends on X86_TSC
503 depends on PCI
504 depends on PCI_GOANY
505 depends on X86_IO_APIC
506 select IOSF_MBI
507 select INTEL_IMR
508 select COMMON_CLK
509 ---help---
510 Select to include support for Quark X1000 SoC.
511 Say Y here if you have a Quark based system such as the Arduino
512 compatible Intel Galileo.
513
514 config X86_INTEL_LPSS
515 bool "Intel Low Power Subsystem Support"
516 depends on ACPI
517 select COMMON_CLK
518 select PINCTRL
519 ---help---
520 Select to build support for Intel Low Power Subsystem such as
521 found on Intel Lynxpoint PCH. Selecting this option enables
522 things like clock tree (common clock framework) and pincontrol
523 which are needed by the LPSS peripheral drivers.
524
525 config X86_AMD_PLATFORM_DEVICE
526 bool "AMD ACPI2Platform devices support"
527 depends on ACPI
528 select COMMON_CLK
529 select PINCTRL
530 ---help---
531 Select to interpret AMD specific ACPI device to platform device
532 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
533 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
534 implemented under PINCTRL subsystem.
535
536 config IOSF_MBI
537 tristate "Intel SoC IOSF Sideband support for SoC platforms"
538 depends on PCI
539 ---help---
540 This option enables sideband register access support for Intel SoC
541 platforms. On these platforms the IOSF sideband is used in lieu of
542 MSR's for some register accesses, mostly but not limited to thermal
543 and power. Drivers may query the availability of this device to
544 determine if they need the sideband in order to work on these
545 platforms. The sideband is available on the following SoC products.
546 This list is not meant to be exclusive.
547 - BayTrail
548 - Braswell
549 - Quark
550
551 You should say Y if you are running a kernel on one of these SoC's.
552
553 config IOSF_MBI_DEBUG
554 bool "Enable IOSF sideband access through debugfs"
555 depends on IOSF_MBI && DEBUG_FS
556 ---help---
557 Select this option to expose the IOSF sideband access registers (MCR,
558 MDR, MCRX) through debugfs to write and read register information from
559 different units on the SoC. This is most useful for obtaining device
560 state information for debug and analysis. As this is a general access
561 mechanism, users of this option would have specific knowledge of the
562 device they want to access.
563
564 If you don't require the option or are in doubt, say N.
565
566 config X86_RDC321X
567 bool "RDC R-321x SoC"
568 depends on X86_32
569 depends on X86_EXTENDED_PLATFORM
570 select M486
571 select X86_REBOOTFIXUPS
572 ---help---
573 This option is needed for RDC R-321x system-on-chip, also known
574 as R-8610-(G).
575 If you don't have one of these chips, you should say N here.
576
577 config X86_32_NON_STANDARD
578 bool "Support non-standard 32-bit SMP architectures"
579 depends on X86_32 && SMP
580 depends on X86_EXTENDED_PLATFORM
581 ---help---
582 This option compiles in the bigsmp and STA2X11 default
583 subarchitectures. It is intended for a generic binary
584 kernel. If you select them all, kernel will probe it one by
585 one and will fallback to default.
586
587 # Alphabetically sorted list of Non standard 32 bit platforms
588
589 config X86_SUPPORTS_MEMORY_FAILURE
590 def_bool y
591 # MCE code calls memory_failure():
592 depends on X86_MCE
593 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
594 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
595 depends on X86_64 || !SPARSEMEM
596 select ARCH_SUPPORTS_MEMORY_FAILURE
597
598 config STA2X11
599 bool "STA2X11 Companion Chip Support"
600 depends on X86_32_NON_STANDARD && PCI
601 select X86_DEV_DMA_OPS
602 select X86_DMA_REMAP
603 select SWIOTLB
604 select MFD_STA2X11
605 select ARCH_REQUIRE_GPIOLIB
606 default n
607 ---help---
608 This adds support for boards based on the STA2X11 IO-Hub,
609 a.k.a. "ConneXt". The chip is used in place of the standard
610 PC chipset, so all "standard" peripherals are missing. If this
611 option is selected the kernel will still be able to boot on
612 standard PC machines.
613
614 config X86_32_IRIS
615 tristate "Eurobraille/Iris poweroff module"
616 depends on X86_32
617 ---help---
618 The Iris machines from EuroBraille do not have APM or ACPI support
619 to shut themselves down properly. A special I/O sequence is
620 needed to do so, which is what this module does at
621 kernel shutdown.
622
623 This is only for Iris machines from EuroBraille.
624
625 If unused, say N.
626
627 config SCHED_OMIT_FRAME_POINTER
628 def_bool y
629 prompt "Single-depth WCHAN output"
630 depends on X86
631 ---help---
632 Calculate simpler /proc/<PID>/wchan values. If this option
633 is disabled then wchan values will recurse back to the
634 caller function. This provides more accurate wchan values,
635 at the expense of slightly more scheduling overhead.
636
637 If in doubt, say "Y".
638
639 menuconfig HYPERVISOR_GUEST
640 bool "Linux guest support"
641 ---help---
642 Say Y here to enable options for running Linux under various hyper-
643 visors. This option enables basic hypervisor detection and platform
644 setup.
645
646 If you say N, all options in this submenu will be skipped and
647 disabled, and Linux guest support won't be built in.
648
649 if HYPERVISOR_GUEST
650
651 config PARAVIRT
652 bool "Enable paravirtualization code"
653 ---help---
654 This changes the kernel so it can modify itself when it is run
655 under a hypervisor, potentially improving performance significantly
656 over full virtualization. However, when run without a hypervisor
657 the kernel is theoretically slower and slightly larger.
658
659 config PARAVIRT_DEBUG
660 bool "paravirt-ops debugging"
661 depends on PARAVIRT && DEBUG_KERNEL
662 ---help---
663 Enable to debug paravirt_ops internals. Specifically, BUG if
664 a paravirt_op is missing when it is called.
665
666 config PARAVIRT_SPINLOCKS
667 bool "Paravirtualization layer for spinlocks"
668 depends on PARAVIRT && SMP
669 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
670 ---help---
671 Paravirtualized spinlocks allow a pvops backend to replace the
672 spinlock implementation with something virtualization-friendly
673 (for example, block the virtual CPU rather than spinning).
674
675 It has a minimal impact on native kernels and gives a nice performance
676 benefit on paravirtualized KVM / Xen kernels.
677
678 If you are unsure how to answer this question, answer Y.
679
680 source "arch/x86/xen/Kconfig"
681
682 config KVM_GUEST
683 bool "KVM Guest support (including kvmclock)"
684 depends on PARAVIRT
685 select PARAVIRT_CLOCK
686 default y
687 ---help---
688 This option enables various optimizations for running under the KVM
689 hypervisor. It includes a paravirtualized clock, so that instead
690 of relying on a PIT (or probably other) emulation by the
691 underlying device model, the host provides the guest with
692 timing infrastructure such as time of day, and system time
693
694 config KVM_DEBUG_FS
695 bool "Enable debug information for KVM Guests in debugfs"
696 depends on KVM_GUEST && DEBUG_FS
697 default n
698 ---help---
699 This option enables collection of various statistics for KVM guest.
700 Statistics are displayed in debugfs filesystem. Enabling this option
701 may incur significant overhead.
702
703 source "arch/x86/lguest/Kconfig"
704
705 config PARAVIRT_TIME_ACCOUNTING
706 bool "Paravirtual steal time accounting"
707 depends on PARAVIRT
708 default n
709 ---help---
710 Select this option to enable fine granularity task steal time
711 accounting. Time spent executing other tasks in parallel with
712 the current vCPU is discounted from the vCPU power. To account for
713 that, there can be a small performance impact.
714
715 If in doubt, say N here.
716
717 config PARAVIRT_CLOCK
718 bool
719
720 endif #HYPERVISOR_GUEST
721
722 config NO_BOOTMEM
723 def_bool y
724
725 source "arch/x86/Kconfig.cpu"
726
727 config HPET_TIMER
728 def_bool X86_64
729 prompt "HPET Timer Support" if X86_32
730 ---help---
731 Use the IA-PC HPET (High Precision Event Timer) to manage
732 time in preference to the PIT and RTC, if a HPET is
733 present.
734 HPET is the next generation timer replacing legacy 8254s.
735 The HPET provides a stable time base on SMP
736 systems, unlike the TSC, but it is more expensive to access,
737 as it is off-chip. You can find the HPET spec at
738 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
739
740 You can safely choose Y here. However, HPET will only be
741 activated if the platform and the BIOS support this feature.
742 Otherwise the 8254 will be used for timing services.
743
744 Choose N to continue using the legacy 8254 timer.
745
746 config HPET_EMULATE_RTC
747 def_bool y
748 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
749
750 config APB_TIMER
751 def_bool y if X86_INTEL_MID
752 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
753 select DW_APB_TIMER
754 depends on X86_INTEL_MID && SFI
755 help
756 APB timer is the replacement for 8254, HPET on X86 MID platforms.
757 The APBT provides a stable time base on SMP
758 systems, unlike the TSC, but it is more expensive to access,
759 as it is off-chip. APB timers are always running regardless of CPU
760 C states, they are used as per CPU clockevent device when possible.
761
762 # Mark as expert because too many people got it wrong.
763 # The code disables itself when not needed.
764 config DMI
765 default y
766 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
767 bool "Enable DMI scanning" if EXPERT
768 ---help---
769 Enabled scanning of DMI to identify machine quirks. Say Y
770 here unless you have verified that your setup is not
771 affected by entries in the DMI blacklist. Required by PNP
772 BIOS code.
773
774 config GART_IOMMU
775 bool "Old AMD GART IOMMU support"
776 select SWIOTLB
777 depends on X86_64 && PCI && AMD_NB
778 ---help---
779 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
780 GART based hardware IOMMUs.
781
782 The GART supports full DMA access for devices with 32-bit access
783 limitations, on systems with more than 3 GB. This is usually needed
784 for USB, sound, many IDE/SATA chipsets and some other devices.
785
786 Newer systems typically have a modern AMD IOMMU, supported via
787 the CONFIG_AMD_IOMMU=y config option.
788
789 In normal configurations this driver is only active when needed:
790 there's more than 3 GB of memory and the system contains a
791 32-bit limited device.
792
793 If unsure, say Y.
794
795 config CALGARY_IOMMU
796 bool "IBM Calgary IOMMU support"
797 select SWIOTLB
798 depends on X86_64 && PCI
799 ---help---
800 Support for hardware IOMMUs in IBM's xSeries x366 and x460
801 systems. Needed to run systems with more than 3GB of memory
802 properly with 32-bit PCI devices that do not support DAC
803 (Double Address Cycle). Calgary also supports bus level
804 isolation, where all DMAs pass through the IOMMU. This
805 prevents them from going anywhere except their intended
806 destination. This catches hard-to-find kernel bugs and
807 mis-behaving drivers and devices that do not use the DMA-API
808 properly to set up their DMA buffers. The IOMMU can be
809 turned off at boot time with the iommu=off parameter.
810 Normally the kernel will make the right choice by itself.
811 If unsure, say Y.
812
813 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
814 def_bool y
815 prompt "Should Calgary be enabled by default?"
816 depends on CALGARY_IOMMU
817 ---help---
818 Should Calgary be enabled by default? if you choose 'y', Calgary
819 will be used (if it exists). If you choose 'n', Calgary will not be
820 used even if it exists. If you choose 'n' and would like to use
821 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
822 If unsure, say Y.
823
824 # need this always selected by IOMMU for the VIA workaround
825 config SWIOTLB
826 def_bool y if X86_64
827 ---help---
828 Support for software bounce buffers used on x86-64 systems
829 which don't have a hardware IOMMU. Using this PCI devices
830 which can only access 32-bits of memory can be used on systems
831 with more than 3 GB of memory.
832 If unsure, say Y.
833
834 config IOMMU_HELPER
835 def_bool y
836 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
837
838 config MAXSMP
839 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
840 depends on X86_64 && SMP && DEBUG_KERNEL
841 select CPUMASK_OFFSTACK
842 ---help---
843 Enable maximum number of CPUS and NUMA Nodes for this architecture.
844 If unsure, say N.
845
846 config NR_CPUS
847 int "Maximum number of CPUs" if SMP && !MAXSMP
848 range 2 8 if SMP && X86_32 && !X86_BIGSMP
849 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
850 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
851 default "1" if !SMP
852 default "8192" if MAXSMP
853 default "32" if SMP && X86_BIGSMP
854 default "8" if SMP && X86_32
855 default "64" if SMP
856 ---help---
857 This allows you to specify the maximum number of CPUs which this
858 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
859 supported value is 8192, otherwise the maximum value is 512. The
860 minimum value which makes sense is 2.
861
862 This is purely to save memory - each supported CPU adds
863 approximately eight kilobytes to the kernel image.
864
865 config SCHED_SMT
866 bool "SMT (Hyperthreading) scheduler support"
867 depends on SMP
868 ---help---
869 SMT scheduler support improves the CPU scheduler's decision making
870 when dealing with Intel Pentium 4 chips with HyperThreading at a
871 cost of slightly increased overhead in some places. If unsure say
872 N here.
873
874 config SCHED_MC
875 def_bool y
876 prompt "Multi-core scheduler support"
877 depends on SMP
878 ---help---
879 Multi-core scheduler support improves the CPU scheduler's decision
880 making when dealing with multi-core CPU chips at a cost of slightly
881 increased overhead in some places. If unsure say N here.
882
883 source "kernel/Kconfig.preempt"
884
885 config UP_LATE_INIT
886 def_bool y
887 depends on !SMP && X86_LOCAL_APIC
888
889 config X86_UP_APIC
890 bool "Local APIC support on uniprocessors" if !PCI_MSI
891 default PCI_MSI
892 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
893 ---help---
894 A local APIC (Advanced Programmable Interrupt Controller) is an
895 integrated interrupt controller in the CPU. If you have a single-CPU
896 system which has a processor with a local APIC, you can say Y here to
897 enable and use it. If you say Y here even though your machine doesn't
898 have a local APIC, then the kernel will still run with no slowdown at
899 all. The local APIC supports CPU-generated self-interrupts (timer,
900 performance counters), and the NMI watchdog which detects hard
901 lockups.
902
903 config X86_UP_IOAPIC
904 bool "IO-APIC support on uniprocessors"
905 depends on X86_UP_APIC
906 ---help---
907 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
908 SMP-capable replacement for PC-style interrupt controllers. Most
909 SMP systems and many recent uniprocessor systems have one.
910
911 If you have a single-CPU system with an IO-APIC, you can say Y here
912 to use it. If you say Y here even though your machine doesn't have
913 an IO-APIC, then the kernel will still run with no slowdown at all.
914
915 config X86_LOCAL_APIC
916 def_bool y
917 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
918 select IRQ_DOMAIN_HIERARCHY
919 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
920
921 config X86_IO_APIC
922 def_bool y
923 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
924
925 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
926 bool "Reroute for broken boot IRQs"
927 depends on X86_IO_APIC
928 ---help---
929 This option enables a workaround that fixes a source of
930 spurious interrupts. This is recommended when threaded
931 interrupt handling is used on systems where the generation of
932 superfluous "boot interrupts" cannot be disabled.
933
934 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
935 entry in the chipset's IO-APIC is masked (as, e.g. the RT
936 kernel does during interrupt handling). On chipsets where this
937 boot IRQ generation cannot be disabled, this workaround keeps
938 the original IRQ line masked so that only the equivalent "boot
939 IRQ" is delivered to the CPUs. The workaround also tells the
940 kernel to set up the IRQ handler on the boot IRQ line. In this
941 way only one interrupt is delivered to the kernel. Otherwise
942 the spurious second interrupt may cause the kernel to bring
943 down (vital) interrupt lines.
944
945 Only affects "broken" chipsets. Interrupt sharing may be
946 increased on these systems.
947
948 config X86_MCE
949 bool "Machine Check / overheating reporting"
950 default y
951 ---help---
952 Machine Check support allows the processor to notify the
953 kernel if it detects a problem (e.g. overheating, data corruption).
954 The action the kernel takes depends on the severity of the problem,
955 ranging from warning messages to halting the machine.
956
957 config X86_MCE_INTEL
958 def_bool y
959 prompt "Intel MCE features"
960 depends on X86_MCE && X86_LOCAL_APIC
961 ---help---
962 Additional support for intel specific MCE features such as
963 the thermal monitor.
964
965 config X86_MCE_AMD
966 def_bool y
967 prompt "AMD MCE features"
968 depends on X86_MCE && X86_LOCAL_APIC
969 ---help---
970 Additional support for AMD specific MCE features such as
971 the DRAM Error Threshold.
972
973 config X86_ANCIENT_MCE
974 bool "Support for old Pentium 5 / WinChip machine checks"
975 depends on X86_32 && X86_MCE
976 ---help---
977 Include support for machine check handling on old Pentium 5 or WinChip
978 systems. These typically need to be enabled explicitly on the command
979 line.
980
981 config X86_MCE_THRESHOLD
982 depends on X86_MCE_AMD || X86_MCE_INTEL
983 def_bool y
984
985 config X86_MCE_INJECT
986 depends on X86_MCE
987 tristate "Machine check injector support"
988 ---help---
989 Provide support for injecting machine checks for testing purposes.
990 If you don't know what a machine check is and you don't do kernel
991 QA it is safe to say n.
992
993 config X86_THERMAL_VECTOR
994 def_bool y
995 depends on X86_MCE_INTEL
996
997 config VM86
998 bool "Enable VM86 support" if EXPERT
999 default y
1000 depends on X86_32
1001 ---help---
1002 This option is required by programs like DOSEMU to run
1003 16-bit real mode legacy code on x86 processors. It also may
1004 be needed by software like XFree86 to initialize some video
1005 cards via BIOS. Disabling this option saves about 6K.
1006
1007 config X86_16BIT
1008 bool "Enable support for 16-bit segments" if EXPERT
1009 default y
1010 ---help---
1011 This option is required by programs like Wine to run 16-bit
1012 protected mode legacy code on x86 processors. Disabling
1013 this option saves about 300 bytes on i386, or around 6K text
1014 plus 16K runtime memory on x86-64,
1015
1016 config X86_ESPFIX32
1017 def_bool y
1018 depends on X86_16BIT && X86_32
1019
1020 config X86_ESPFIX64
1021 def_bool y
1022 depends on X86_16BIT && X86_64
1023
1024 config X86_VSYSCALL_EMULATION
1025 bool "Enable vsyscall emulation" if EXPERT
1026 default y
1027 depends on X86_64
1028 ---help---
1029 This enables emulation of the legacy vsyscall page. Disabling
1030 it is roughly equivalent to booting with vsyscall=none, except
1031 that it will also disable the helpful warning if a program
1032 tries to use a vsyscall. With this option set to N, offending
1033 programs will just segfault, citing addresses of the form
1034 0xffffffffff600?00.
1035
1036 This option is required by many programs built before 2013, and
1037 care should be used even with newer programs if set to N.
1038
1039 Disabling this option saves about 7K of kernel size and
1040 possibly 4K of additional runtime pagetable memory.
1041
1042 config TOSHIBA
1043 tristate "Toshiba Laptop support"
1044 depends on X86_32
1045 ---help---
1046 This adds a driver to safely access the System Management Mode of
1047 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1048 not work on models with a Phoenix BIOS. The System Management Mode
1049 is used to set the BIOS and power saving options on Toshiba portables.
1050
1051 For information on utilities to make use of this driver see the
1052 Toshiba Linux utilities web site at:
1053 <http://www.buzzard.org.uk/toshiba/>.
1054
1055 Say Y if you intend to run this kernel on a Toshiba portable.
1056 Say N otherwise.
1057
1058 config I8K
1059 tristate "Dell i8k legacy laptop support"
1060 select HWMON
1061 select SENSORS_DELL_SMM
1062 ---help---
1063 This option enables legacy /proc/i8k userspace interface in hwmon
1064 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1065 temperature and allows controlling fan speeds of Dell laptops via
1066 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1067 it reports also power and hotkey status. For fan speed control is
1068 needed userspace package i8kutils.
1069
1070 Say Y if you intend to run this kernel on old Dell laptops or want to
1071 use userspace package i8kutils.
1072 Say N otherwise.
1073
1074 config X86_REBOOTFIXUPS
1075 bool "Enable X86 board specific fixups for reboot"
1076 depends on X86_32
1077 ---help---
1078 This enables chipset and/or board specific fixups to be done
1079 in order to get reboot to work correctly. This is only needed on
1080 some combinations of hardware and BIOS. The symptom, for which
1081 this config is intended, is when reboot ends with a stalled/hung
1082 system.
1083
1084 Currently, the only fixup is for the Geode machines using
1085 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1086
1087 Say Y if you want to enable the fixup. Currently, it's safe to
1088 enable this option even if you don't need it.
1089 Say N otherwise.
1090
1091 config MICROCODE
1092 tristate "CPU microcode loading support"
1093 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1094 select FW_LOADER
1095 ---help---
1096
1097 If you say Y here, you will be able to update the microcode on
1098 certain Intel and AMD processors. The Intel support is for the
1099 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1100 Xeon etc. The AMD support is for families 0x10 and later. You will
1101 obviously need the actual microcode binary data itself which is not
1102 shipped with the Linux kernel.
1103
1104 This option selects the general module only, you need to select
1105 at least one vendor specific module as well.
1106
1107 To compile this driver as a module, choose M here: the module
1108 will be called microcode.
1109
1110 config MICROCODE_INTEL
1111 bool "Intel microcode loading support"
1112 depends on MICROCODE
1113 default MICROCODE
1114 select FW_LOADER
1115 ---help---
1116 This options enables microcode patch loading support for Intel
1117 processors.
1118
1119 For the current Intel microcode data package go to
1120 <https://downloadcenter.intel.com> and search for
1121 'Linux Processor Microcode Data File'.
1122
1123 config MICROCODE_AMD
1124 bool "AMD microcode loading support"
1125 depends on MICROCODE
1126 select FW_LOADER
1127 ---help---
1128 If you select this option, microcode patch loading support for AMD
1129 processors will be enabled.
1130
1131 config MICROCODE_OLD_INTERFACE
1132 def_bool y
1133 depends on MICROCODE
1134
1135 config MICROCODE_INTEL_EARLY
1136 bool
1137
1138 config MICROCODE_AMD_EARLY
1139 bool
1140
1141 config MICROCODE_EARLY
1142 bool "Early load microcode"
1143 depends on MICROCODE=y && BLK_DEV_INITRD
1144 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1145 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1146 default y
1147 help
1148 This option provides functionality to read additional microcode data
1149 at the beginning of initrd image. The data tells kernel to load
1150 microcode to CPU's as early as possible. No functional change if no
1151 microcode data is glued to the initrd, therefore it's safe to say Y.
1152
1153 config X86_MSR
1154 tristate "/dev/cpu/*/msr - Model-specific register support"
1155 ---help---
1156 This device gives privileged processes access to the x86
1157 Model-Specific Registers (MSRs). It is a character device with
1158 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1159 MSR accesses are directed to a specific CPU on multi-processor
1160 systems.
1161
1162 config X86_CPUID
1163 tristate "/dev/cpu/*/cpuid - CPU information support"
1164 ---help---
1165 This device gives processes access to the x86 CPUID instruction to
1166 be executed on a specific processor. It is a character device
1167 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1168 /dev/cpu/31/cpuid.
1169
1170 choice
1171 prompt "High Memory Support"
1172 default HIGHMEM4G
1173 depends on X86_32
1174
1175 config NOHIGHMEM
1176 bool "off"
1177 ---help---
1178 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1179 However, the address space of 32-bit x86 processors is only 4
1180 Gigabytes large. That means that, if you have a large amount of
1181 physical memory, not all of it can be "permanently mapped" by the
1182 kernel. The physical memory that's not permanently mapped is called
1183 "high memory".
1184
1185 If you are compiling a kernel which will never run on a machine with
1186 more than 1 Gigabyte total physical RAM, answer "off" here (default
1187 choice and suitable for most users). This will result in a "3GB/1GB"
1188 split: 3GB are mapped so that each process sees a 3GB virtual memory
1189 space and the remaining part of the 4GB virtual memory space is used
1190 by the kernel to permanently map as much physical memory as
1191 possible.
1192
1193 If the machine has between 1 and 4 Gigabytes physical RAM, then
1194 answer "4GB" here.
1195
1196 If more than 4 Gigabytes is used then answer "64GB" here. This
1197 selection turns Intel PAE (Physical Address Extension) mode on.
1198 PAE implements 3-level paging on IA32 processors. PAE is fully
1199 supported by Linux, PAE mode is implemented on all recent Intel
1200 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1201 then the kernel will not boot on CPUs that don't support PAE!
1202
1203 The actual amount of total physical memory will either be
1204 auto detected or can be forced by using a kernel command line option
1205 such as "mem=256M". (Try "man bootparam" or see the documentation of
1206 your boot loader (lilo or loadlin) about how to pass options to the
1207 kernel at boot time.)
1208
1209 If unsure, say "off".
1210
1211 config HIGHMEM4G
1212 bool "4GB"
1213 ---help---
1214 Select this if you have a 32-bit processor and between 1 and 4
1215 gigabytes of physical RAM.
1216
1217 config HIGHMEM64G
1218 bool "64GB"
1219 depends on !M486
1220 select X86_PAE
1221 ---help---
1222 Select this if you have a 32-bit processor and more than 4
1223 gigabytes of physical RAM.
1224
1225 endchoice
1226
1227 choice
1228 prompt "Memory split" if EXPERT
1229 default VMSPLIT_3G
1230 depends on X86_32
1231 ---help---
1232 Select the desired split between kernel and user memory.
1233
1234 If the address range available to the kernel is less than the
1235 physical memory installed, the remaining memory will be available
1236 as "high memory". Accessing high memory is a little more costly
1237 than low memory, as it needs to be mapped into the kernel first.
1238 Note that increasing the kernel address space limits the range
1239 available to user programs, making the address space there
1240 tighter. Selecting anything other than the default 3G/1G split
1241 will also likely make your kernel incompatible with binary-only
1242 kernel modules.
1243
1244 If you are not absolutely sure what you are doing, leave this
1245 option alone!
1246
1247 config VMSPLIT_3G
1248 bool "3G/1G user/kernel split"
1249 config VMSPLIT_3G_OPT
1250 depends on !X86_PAE
1251 bool "3G/1G user/kernel split (for full 1G low memory)"
1252 config VMSPLIT_2G
1253 bool "2G/2G user/kernel split"
1254 config VMSPLIT_2G_OPT
1255 depends on !X86_PAE
1256 bool "2G/2G user/kernel split (for full 2G low memory)"
1257 config VMSPLIT_1G
1258 bool "1G/3G user/kernel split"
1259 endchoice
1260
1261 config PAGE_OFFSET
1262 hex
1263 default 0xB0000000 if VMSPLIT_3G_OPT
1264 default 0x80000000 if VMSPLIT_2G
1265 default 0x78000000 if VMSPLIT_2G_OPT
1266 default 0x40000000 if VMSPLIT_1G
1267 default 0xC0000000
1268 depends on X86_32
1269
1270 config HIGHMEM
1271 def_bool y
1272 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1273
1274 config X86_PAE
1275 bool "PAE (Physical Address Extension) Support"
1276 depends on X86_32 && !HIGHMEM4G
1277 ---help---
1278 PAE is required for NX support, and furthermore enables
1279 larger swapspace support for non-overcommit purposes. It
1280 has the cost of more pagetable lookup overhead, and also
1281 consumes more pagetable space per process.
1282
1283 config ARCH_PHYS_ADDR_T_64BIT
1284 def_bool y
1285 depends on X86_64 || X86_PAE
1286
1287 config ARCH_DMA_ADDR_T_64BIT
1288 def_bool y
1289 depends on X86_64 || HIGHMEM64G
1290
1291 config X86_DIRECT_GBPAGES
1292 def_bool y
1293 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1294 ---help---
1295 Certain kernel features effectively disable kernel
1296 linear 1 GB mappings (even if the CPU otherwise
1297 supports them), so don't confuse the user by printing
1298 that we have them enabled.
1299
1300 # Common NUMA Features
1301 config NUMA
1302 bool "Numa Memory Allocation and Scheduler Support"
1303 depends on SMP
1304 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1305 default y if X86_BIGSMP
1306 ---help---
1307 Enable NUMA (Non Uniform Memory Access) support.
1308
1309 The kernel will try to allocate memory used by a CPU on the
1310 local memory controller of the CPU and add some more
1311 NUMA awareness to the kernel.
1312
1313 For 64-bit this is recommended if the system is Intel Core i7
1314 (or later), AMD Opteron, or EM64T NUMA.
1315
1316 For 32-bit this is only needed if you boot a 32-bit
1317 kernel on a 64-bit NUMA platform.
1318
1319 Otherwise, you should say N.
1320
1321 config AMD_NUMA
1322 def_bool y
1323 prompt "Old style AMD Opteron NUMA detection"
1324 depends on X86_64 && NUMA && PCI
1325 ---help---
1326 Enable AMD NUMA node topology detection. You should say Y here if
1327 you have a multi processor AMD system. This uses an old method to
1328 read the NUMA configuration directly from the builtin Northbridge
1329 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1330 which also takes priority if both are compiled in.
1331
1332 config X86_64_ACPI_NUMA
1333 def_bool y
1334 prompt "ACPI NUMA detection"
1335 depends on X86_64 && NUMA && ACPI && PCI
1336 select ACPI_NUMA
1337 ---help---
1338 Enable ACPI SRAT based node topology detection.
1339
1340 # Some NUMA nodes have memory ranges that span
1341 # other nodes. Even though a pfn is valid and
1342 # between a node's start and end pfns, it may not
1343 # reside on that node. See memmap_init_zone()
1344 # for details.
1345 config NODES_SPAN_OTHER_NODES
1346 def_bool y
1347 depends on X86_64_ACPI_NUMA
1348
1349 config NUMA_EMU
1350 bool "NUMA emulation"
1351 depends on NUMA
1352 ---help---
1353 Enable NUMA emulation. A flat machine will be split
1354 into virtual nodes when booted with "numa=fake=N", where N is the
1355 number of nodes. This is only useful for debugging.
1356
1357 config NODES_SHIFT
1358 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1359 range 1 10
1360 default "10" if MAXSMP
1361 default "6" if X86_64
1362 default "3"
1363 depends on NEED_MULTIPLE_NODES
1364 ---help---
1365 Specify the maximum number of NUMA Nodes available on the target
1366 system. Increases memory reserved to accommodate various tables.
1367
1368 config ARCH_HAVE_MEMORY_PRESENT
1369 def_bool y
1370 depends on X86_32 && DISCONTIGMEM
1371
1372 config NEED_NODE_MEMMAP_SIZE
1373 def_bool y
1374 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1375
1376 config ARCH_FLATMEM_ENABLE
1377 def_bool y
1378 depends on X86_32 && !NUMA
1379
1380 config ARCH_DISCONTIGMEM_ENABLE
1381 def_bool y
1382 depends on NUMA && X86_32
1383
1384 config ARCH_DISCONTIGMEM_DEFAULT
1385 def_bool y
1386 depends on NUMA && X86_32
1387
1388 config ARCH_SPARSEMEM_ENABLE
1389 def_bool y
1390 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1391 select SPARSEMEM_STATIC if X86_32
1392 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1393
1394 config ARCH_SPARSEMEM_DEFAULT
1395 def_bool y
1396 depends on X86_64
1397
1398 config ARCH_SELECT_MEMORY_MODEL
1399 def_bool y
1400 depends on ARCH_SPARSEMEM_ENABLE
1401
1402 config ARCH_MEMORY_PROBE
1403 bool "Enable sysfs memory/probe interface"
1404 depends on X86_64 && MEMORY_HOTPLUG
1405 help
1406 This option enables a sysfs memory/probe interface for testing.
1407 See Documentation/memory-hotplug.txt for more information.
1408 If you are unsure how to answer this question, answer N.
1409
1410 config ARCH_PROC_KCORE_TEXT
1411 def_bool y
1412 depends on X86_64 && PROC_KCORE
1413
1414 config ILLEGAL_POINTER_VALUE
1415 hex
1416 default 0 if X86_32
1417 default 0xdead000000000000 if X86_64
1418
1419 source "mm/Kconfig"
1420
1421 config X86_PMEM_LEGACY
1422 bool "Support non-standard NVDIMMs and ADR protected memory"
1423 depends on PHYS_ADDR_T_64BIT
1424 depends on BLK_DEV
1425 select LIBNVDIMM
1426 help
1427 Treat memory marked using the non-standard e820 type of 12 as used
1428 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1429 The kernel will offer these regions to the 'pmem' driver so
1430 they can be used for persistent storage.
1431
1432 Say Y if unsure.
1433
1434 config HIGHPTE
1435 bool "Allocate 3rd-level pagetables from highmem"
1436 depends on HIGHMEM
1437 ---help---
1438 The VM uses one page table entry for each page of physical memory.
1439 For systems with a lot of RAM, this can be wasteful of precious
1440 low memory. Setting this option will put user-space page table
1441 entries in high memory.
1442
1443 config X86_CHECK_BIOS_CORRUPTION
1444 bool "Check for low memory corruption"
1445 ---help---
1446 Periodically check for memory corruption in low memory, which
1447 is suspected to be caused by BIOS. Even when enabled in the
1448 configuration, it is disabled at runtime. Enable it by
1449 setting "memory_corruption_check=1" on the kernel command
1450 line. By default it scans the low 64k of memory every 60
1451 seconds; see the memory_corruption_check_size and
1452 memory_corruption_check_period parameters in
1453 Documentation/kernel-parameters.txt to adjust this.
1454
1455 When enabled with the default parameters, this option has
1456 almost no overhead, as it reserves a relatively small amount
1457 of memory and scans it infrequently. It both detects corruption
1458 and prevents it from affecting the running system.
1459
1460 It is, however, intended as a diagnostic tool; if repeatable
1461 BIOS-originated corruption always affects the same memory,
1462 you can use memmap= to prevent the kernel from using that
1463 memory.
1464
1465 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1466 bool "Set the default setting of memory_corruption_check"
1467 depends on X86_CHECK_BIOS_CORRUPTION
1468 default y
1469 ---help---
1470 Set whether the default state of memory_corruption_check is
1471 on or off.
1472
1473 config X86_RESERVE_LOW
1474 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1475 default 64
1476 range 4 640
1477 ---help---
1478 Specify the amount of low memory to reserve for the BIOS.
1479
1480 The first page contains BIOS data structures that the kernel
1481 must not use, so that page must always be reserved.
1482
1483 By default we reserve the first 64K of physical RAM, as a
1484 number of BIOSes are known to corrupt that memory range
1485 during events such as suspend/resume or monitor cable
1486 insertion, so it must not be used by the kernel.
1487
1488 You can set this to 4 if you are absolutely sure that you
1489 trust the BIOS to get all its memory reservations and usages
1490 right. If you know your BIOS have problems beyond the
1491 default 64K area, you can set this to 640 to avoid using the
1492 entire low memory range.
1493
1494 If you have doubts about the BIOS (e.g. suspend/resume does
1495 not work or there's kernel crashes after certain hardware
1496 hotplug events) then you might want to enable
1497 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1498 typical corruption patterns.
1499
1500 Leave this to the default value of 64 if you are unsure.
1501
1502 config MATH_EMULATION
1503 bool
1504 prompt "Math emulation" if X86_32
1505 ---help---
1506 Linux can emulate a math coprocessor (used for floating point
1507 operations) if you don't have one. 486DX and Pentium processors have
1508 a math coprocessor built in, 486SX and 386 do not, unless you added
1509 a 487DX or 387, respectively. (The messages during boot time can
1510 give you some hints here ["man dmesg"].) Everyone needs either a
1511 coprocessor or this emulation.
1512
1513 If you don't have a math coprocessor, you need to say Y here; if you
1514 say Y here even though you have a coprocessor, the coprocessor will
1515 be used nevertheless. (This behavior can be changed with the kernel
1516 command line option "no387", which comes handy if your coprocessor
1517 is broken. Try "man bootparam" or see the documentation of your boot
1518 loader (lilo or loadlin) about how to pass options to the kernel at
1519 boot time.) This means that it is a good idea to say Y here if you
1520 intend to use this kernel on different machines.
1521
1522 More information about the internals of the Linux math coprocessor
1523 emulation can be found in <file:arch/x86/math-emu/README>.
1524
1525 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1526 kernel, it won't hurt.
1527
1528 config MTRR
1529 def_bool y
1530 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1531 ---help---
1532 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1533 the Memory Type Range Registers (MTRRs) may be used to control
1534 processor access to memory ranges. This is most useful if you have
1535 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1536 allows bus write transfers to be combined into a larger transfer
1537 before bursting over the PCI/AGP bus. This can increase performance
1538 of image write operations 2.5 times or more. Saying Y here creates a
1539 /proc/mtrr file which may be used to manipulate your processor's
1540 MTRRs. Typically the X server should use this.
1541
1542 This code has a reasonably generic interface so that similar
1543 control registers on other processors can be easily supported
1544 as well:
1545
1546 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1547 Registers (ARRs) which provide a similar functionality to MTRRs. For
1548 these, the ARRs are used to emulate the MTRRs.
1549 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1550 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1551 write-combining. All of these processors are supported by this code
1552 and it makes sense to say Y here if you have one of them.
1553
1554 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1555 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1556 can lead to all sorts of problems, so it's good to say Y here.
1557
1558 You can safely say Y even if your machine doesn't have MTRRs, you'll
1559 just add about 9 KB to your kernel.
1560
1561 See <file:Documentation/x86/mtrr.txt> for more information.
1562
1563 config MTRR_SANITIZER
1564 def_bool y
1565 prompt "MTRR cleanup support"
1566 depends on MTRR
1567 ---help---
1568 Convert MTRR layout from continuous to discrete, so X drivers can
1569 add writeback entries.
1570
1571 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1572 The largest mtrr entry size for a continuous block can be set with
1573 mtrr_chunk_size.
1574
1575 If unsure, say Y.
1576
1577 config MTRR_SANITIZER_ENABLE_DEFAULT
1578 int "MTRR cleanup enable value (0-1)"
1579 range 0 1
1580 default "0"
1581 depends on MTRR_SANITIZER
1582 ---help---
1583 Enable mtrr cleanup default value
1584
1585 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1586 int "MTRR cleanup spare reg num (0-7)"
1587 range 0 7
1588 default "1"
1589 depends on MTRR_SANITIZER
1590 ---help---
1591 mtrr cleanup spare entries default, it can be changed via
1592 mtrr_spare_reg_nr=N on the kernel command line.
1593
1594 config X86_PAT
1595 def_bool y
1596 prompt "x86 PAT support" if EXPERT
1597 depends on MTRR
1598 ---help---
1599 Use PAT attributes to setup page level cache control.
1600
1601 PATs are the modern equivalents of MTRRs and are much more
1602 flexible than MTRRs.
1603
1604 Say N here if you see bootup problems (boot crash, boot hang,
1605 spontaneous reboots) or a non-working video driver.
1606
1607 If unsure, say Y.
1608
1609 config ARCH_USES_PG_UNCACHED
1610 def_bool y
1611 depends on X86_PAT
1612
1613 config ARCH_RANDOM
1614 def_bool y
1615 prompt "x86 architectural random number generator" if EXPERT
1616 ---help---
1617 Enable the x86 architectural RDRAND instruction
1618 (Intel Bull Mountain technology) to generate random numbers.
1619 If supported, this is a high bandwidth, cryptographically
1620 secure hardware random number generator.
1621
1622 config X86_SMAP
1623 def_bool y
1624 prompt "Supervisor Mode Access Prevention" if EXPERT
1625 ---help---
1626 Supervisor Mode Access Prevention (SMAP) is a security
1627 feature in newer Intel processors. There is a small
1628 performance cost if this enabled and turned on; there is
1629 also a small increase in the kernel size if this is enabled.
1630
1631 If unsure, say Y.
1632
1633 config X86_INTEL_MPX
1634 prompt "Intel MPX (Memory Protection Extensions)"
1635 def_bool n
1636 depends on CPU_SUP_INTEL
1637 ---help---
1638 MPX provides hardware features that can be used in
1639 conjunction with compiler-instrumented code to check
1640 memory references. It is designed to detect buffer
1641 overflow or underflow bugs.
1642
1643 This option enables running applications which are
1644 instrumented or otherwise use MPX. It does not use MPX
1645 itself inside the kernel or to protect the kernel
1646 against bad memory references.
1647
1648 Enabling this option will make the kernel larger:
1649 ~8k of kernel text and 36 bytes of data on a 64-bit
1650 defconfig. It adds a long to the 'mm_struct' which
1651 will increase the kernel memory overhead of each
1652 process and adds some branches to paths used during
1653 exec() and munmap().
1654
1655 For details, see Documentation/x86/intel_mpx.txt
1656
1657 If unsure, say N.
1658
1659 config EFI
1660 bool "EFI runtime service support"
1661 depends on ACPI
1662 select UCS2_STRING
1663 select EFI_RUNTIME_WRAPPERS
1664 ---help---
1665 This enables the kernel to use EFI runtime services that are
1666 available (such as the EFI variable services).
1667
1668 This option is only useful on systems that have EFI firmware.
1669 In addition, you should use the latest ELILO loader available
1670 at <http://elilo.sourceforge.net> in order to take advantage
1671 of EFI runtime services. However, even with this option, the
1672 resultant kernel should continue to boot on existing non-EFI
1673 platforms.
1674
1675 config EFI_STUB
1676 bool "EFI stub support"
1677 depends on EFI && !X86_USE_3DNOW
1678 select RELOCATABLE
1679 ---help---
1680 This kernel feature allows a bzImage to be loaded directly
1681 by EFI firmware without the use of a bootloader.
1682
1683 See Documentation/efi-stub.txt for more information.
1684
1685 config EFI_MIXED
1686 bool "EFI mixed-mode support"
1687 depends on EFI_STUB && X86_64
1688 ---help---
1689 Enabling this feature allows a 64-bit kernel to be booted
1690 on a 32-bit firmware, provided that your CPU supports 64-bit
1691 mode.
1692
1693 Note that it is not possible to boot a mixed-mode enabled
1694 kernel via the EFI boot stub - a bootloader that supports
1695 the EFI handover protocol must be used.
1696
1697 If unsure, say N.
1698
1699 config SECCOMP
1700 def_bool y
1701 prompt "Enable seccomp to safely compute untrusted bytecode"
1702 ---help---
1703 This kernel feature is useful for number crunching applications
1704 that may need to compute untrusted bytecode during their
1705 execution. By using pipes or other transports made available to
1706 the process as file descriptors supporting the read/write
1707 syscalls, it's possible to isolate those applications in
1708 their own address space using seccomp. Once seccomp is
1709 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1710 and the task is only allowed to execute a few safe syscalls
1711 defined by each seccomp mode.
1712
1713 If unsure, say Y. Only embedded should say N here.
1714
1715 source kernel/Kconfig.hz
1716
1717 config KEXEC
1718 bool "kexec system call"
1719 ---help---
1720 kexec is a system call that implements the ability to shutdown your
1721 current kernel, and to start another kernel. It is like a reboot
1722 but it is independent of the system firmware. And like a reboot
1723 you can start any kernel with it, not just Linux.
1724
1725 The name comes from the similarity to the exec system call.
1726
1727 It is an ongoing process to be certain the hardware in a machine
1728 is properly shutdown, so do not be surprised if this code does not
1729 initially work for you. As of this writing the exact hardware
1730 interface is strongly in flux, so no good recommendation can be
1731 made.
1732
1733 config KEXEC_FILE
1734 bool "kexec file based system call"
1735 select BUILD_BIN2C
1736 depends on KEXEC
1737 depends on X86_64
1738 depends on CRYPTO=y
1739 depends on CRYPTO_SHA256=y
1740 ---help---
1741 This is new version of kexec system call. This system call is
1742 file based and takes file descriptors as system call argument
1743 for kernel and initramfs as opposed to list of segments as
1744 accepted by previous system call.
1745
1746 config KEXEC_VERIFY_SIG
1747 bool "Verify kernel signature during kexec_file_load() syscall"
1748 depends on KEXEC_FILE
1749 ---help---
1750 This option makes kernel signature verification mandatory for
1751 the kexec_file_load() syscall.
1752
1753 In addition to that option, you need to enable signature
1754 verification for the corresponding kernel image type being
1755 loaded in order for this to work.
1756
1757 config KEXEC_BZIMAGE_VERIFY_SIG
1758 bool "Enable bzImage signature verification support"
1759 depends on KEXEC_VERIFY_SIG
1760 depends on SIGNED_PE_FILE_VERIFICATION
1761 select SYSTEM_TRUSTED_KEYRING
1762 ---help---
1763 Enable bzImage signature verification support.
1764
1765 config CRASH_DUMP
1766 bool "kernel crash dumps"
1767 depends on X86_64 || (X86_32 && HIGHMEM)
1768 ---help---
1769 Generate crash dump after being started by kexec.
1770 This should be normally only set in special crash dump kernels
1771 which are loaded in the main kernel with kexec-tools into
1772 a specially reserved region and then later executed after
1773 a crash by kdump/kexec. The crash dump kernel must be compiled
1774 to a memory address not used by the main kernel or BIOS using
1775 PHYSICAL_START, or it must be built as a relocatable image
1776 (CONFIG_RELOCATABLE=y).
1777 For more details see Documentation/kdump/kdump.txt
1778
1779 config KEXEC_JUMP
1780 bool "kexec jump"
1781 depends on KEXEC && HIBERNATION
1782 ---help---
1783 Jump between original kernel and kexeced kernel and invoke
1784 code in physical address mode via KEXEC
1785
1786 config PHYSICAL_START
1787 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1788 default "0x1000000"
1789 ---help---
1790 This gives the physical address where the kernel is loaded.
1791
1792 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1793 bzImage will decompress itself to above physical address and
1794 run from there. Otherwise, bzImage will run from the address where
1795 it has been loaded by the boot loader and will ignore above physical
1796 address.
1797
1798 In normal kdump cases one does not have to set/change this option
1799 as now bzImage can be compiled as a completely relocatable image
1800 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1801 address. This option is mainly useful for the folks who don't want
1802 to use a bzImage for capturing the crash dump and want to use a
1803 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1804 to be specifically compiled to run from a specific memory area
1805 (normally a reserved region) and this option comes handy.
1806
1807 So if you are using bzImage for capturing the crash dump,
1808 leave the value here unchanged to 0x1000000 and set
1809 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1810 for capturing the crash dump change this value to start of
1811 the reserved region. In other words, it can be set based on
1812 the "X" value as specified in the "crashkernel=YM@XM"
1813 command line boot parameter passed to the panic-ed
1814 kernel. Please take a look at Documentation/kdump/kdump.txt
1815 for more details about crash dumps.
1816
1817 Usage of bzImage for capturing the crash dump is recommended as
1818 one does not have to build two kernels. Same kernel can be used
1819 as production kernel and capture kernel. Above option should have
1820 gone away after relocatable bzImage support is introduced. But it
1821 is present because there are users out there who continue to use
1822 vmlinux for dump capture. This option should go away down the
1823 line.
1824
1825 Don't change this unless you know what you are doing.
1826
1827 config RELOCATABLE
1828 bool "Build a relocatable kernel"
1829 default y
1830 ---help---
1831 This builds a kernel image that retains relocation information
1832 so it can be loaded someplace besides the default 1MB.
1833 The relocations tend to make the kernel binary about 10% larger,
1834 but are discarded at runtime.
1835
1836 One use is for the kexec on panic case where the recovery kernel
1837 must live at a different physical address than the primary
1838 kernel.
1839
1840 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1841 it has been loaded at and the compile time physical address
1842 (CONFIG_PHYSICAL_START) is used as the minimum location.
1843
1844 config RANDOMIZE_BASE
1845 bool "Randomize the address of the kernel image"
1846 depends on RELOCATABLE
1847 default n
1848 ---help---
1849 Randomizes the physical and virtual address at which the
1850 kernel image is decompressed, as a security feature that
1851 deters exploit attempts relying on knowledge of the location
1852 of kernel internals.
1853
1854 Entropy is generated using the RDRAND instruction if it is
1855 supported. If RDTSC is supported, it is used as well. If
1856 neither RDRAND nor RDTSC are supported, then randomness is
1857 read from the i8254 timer.
1858
1859 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1860 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1861 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1862 minimum of 2MiB, only 10 bits of entropy is theoretically
1863 possible. At best, due to page table layouts, 64-bit can use
1864 9 bits of entropy and 32-bit uses 8 bits.
1865
1866 If unsure, say N.
1867
1868 config RANDOMIZE_BASE_MAX_OFFSET
1869 hex "Maximum kASLR offset allowed" if EXPERT
1870 depends on RANDOMIZE_BASE
1871 range 0x0 0x20000000 if X86_32
1872 default "0x20000000" if X86_32
1873 range 0x0 0x40000000 if X86_64
1874 default "0x40000000" if X86_64
1875 ---help---
1876 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1877 memory is used to determine the maximal offset in bytes that will
1878 be applied to the kernel when kernel Address Space Layout
1879 Randomization (kASLR) is active. This must be a multiple of
1880 PHYSICAL_ALIGN.
1881
1882 On 32-bit this is limited to 512MiB by page table layouts. The
1883 default is 512MiB.
1884
1885 On 64-bit this is limited by how the kernel fixmap page table is
1886 positioned, so this cannot be larger than 1GiB currently. Without
1887 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1888 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1889 modules area will shrink to compensate, up to the current maximum
1890 1GiB to 1GiB split. The default is 1GiB.
1891
1892 If unsure, leave at the default value.
1893
1894 # Relocation on x86 needs some additional build support
1895 config X86_NEED_RELOCS
1896 def_bool y
1897 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1898
1899 config PHYSICAL_ALIGN
1900 hex "Alignment value to which kernel should be aligned"
1901 default "0x200000"
1902 range 0x2000 0x1000000 if X86_32
1903 range 0x200000 0x1000000 if X86_64
1904 ---help---
1905 This value puts the alignment restrictions on physical address
1906 where kernel is loaded and run from. Kernel is compiled for an
1907 address which meets above alignment restriction.
1908
1909 If bootloader loads the kernel at a non-aligned address and
1910 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1911 address aligned to above value and run from there.
1912
1913 If bootloader loads the kernel at a non-aligned address and
1914 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1915 load address and decompress itself to the address it has been
1916 compiled for and run from there. The address for which kernel is
1917 compiled already meets above alignment restrictions. Hence the
1918 end result is that kernel runs from a physical address meeting
1919 above alignment restrictions.
1920
1921 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1922 this value must be a multiple of 0x200000.
1923
1924 Don't change this unless you know what you are doing.
1925
1926 config HOTPLUG_CPU
1927 bool "Support for hot-pluggable CPUs"
1928 depends on SMP
1929 ---help---
1930 Say Y here to allow turning CPUs off and on. CPUs can be
1931 controlled through /sys/devices/system/cpu.
1932 ( Note: power management support will enable this option
1933 automatically on SMP systems. )
1934 Say N if you want to disable CPU hotplug.
1935
1936 config BOOTPARAM_HOTPLUG_CPU0
1937 bool "Set default setting of cpu0_hotpluggable"
1938 default n
1939 depends on HOTPLUG_CPU
1940 ---help---
1941 Set whether default state of cpu0_hotpluggable is on or off.
1942
1943 Say Y here to enable CPU0 hotplug by default. If this switch
1944 is turned on, there is no need to give cpu0_hotplug kernel
1945 parameter and the CPU0 hotplug feature is enabled by default.
1946
1947 Please note: there are two known CPU0 dependencies if you want
1948 to enable the CPU0 hotplug feature either by this switch or by
1949 cpu0_hotplug kernel parameter.
1950
1951 First, resume from hibernate or suspend always starts from CPU0.
1952 So hibernate and suspend are prevented if CPU0 is offline.
1953
1954 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1955 offline if any interrupt can not migrate out of CPU0. There may
1956 be other CPU0 dependencies.
1957
1958 Please make sure the dependencies are under your control before
1959 you enable this feature.
1960
1961 Say N if you don't want to enable CPU0 hotplug feature by default.
1962 You still can enable the CPU0 hotplug feature at boot by kernel
1963 parameter cpu0_hotplug.
1964
1965 config DEBUG_HOTPLUG_CPU0
1966 def_bool n
1967 prompt "Debug CPU0 hotplug"
1968 depends on HOTPLUG_CPU
1969 ---help---
1970 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1971 soon as possible and boots up userspace with CPU0 offlined. User
1972 can online CPU0 back after boot time.
1973
1974 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1975 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1976 compilation or giving cpu0_hotplug kernel parameter at boot.
1977
1978 If unsure, say N.
1979
1980 config COMPAT_VDSO
1981 def_bool n
1982 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1983 depends on X86_32 || IA32_EMULATION
1984 ---help---
1985 Certain buggy versions of glibc will crash if they are
1986 presented with a 32-bit vDSO that is not mapped at the address
1987 indicated in its segment table.
1988
1989 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1990 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1991 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
1992 the only released version with the bug, but OpenSUSE 9
1993 contains a buggy "glibc 2.3.2".
1994
1995 The symptom of the bug is that everything crashes on startup, saying:
1996 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1997
1998 Saying Y here changes the default value of the vdso32 boot
1999 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2000 This works around the glibc bug but hurts performance.
2001
2002 If unsure, say N: if you are compiling your own kernel, you
2003 are unlikely to be using a buggy version of glibc.
2004
2005 config CMDLINE_BOOL
2006 bool "Built-in kernel command line"
2007 ---help---
2008 Allow for specifying boot arguments to the kernel at
2009 build time. On some systems (e.g. embedded ones), it is
2010 necessary or convenient to provide some or all of the
2011 kernel boot arguments with the kernel itself (that is,
2012 to not rely on the boot loader to provide them.)
2013
2014 To compile command line arguments into the kernel,
2015 set this option to 'Y', then fill in the
2016 the boot arguments in CONFIG_CMDLINE.
2017
2018 Systems with fully functional boot loaders (i.e. non-embedded)
2019 should leave this option set to 'N'.
2020
2021 config CMDLINE
2022 string "Built-in kernel command string"
2023 depends on CMDLINE_BOOL
2024 default ""
2025 ---help---
2026 Enter arguments here that should be compiled into the kernel
2027 image and used at boot time. If the boot loader provides a
2028 command line at boot time, it is appended to this string to
2029 form the full kernel command line, when the system boots.
2030
2031 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2032 change this behavior.
2033
2034 In most cases, the command line (whether built-in or provided
2035 by the boot loader) should specify the device for the root
2036 file system.
2037
2038 config CMDLINE_OVERRIDE
2039 bool "Built-in command line overrides boot loader arguments"
2040 depends on CMDLINE_BOOL
2041 ---help---
2042 Set this option to 'Y' to have the kernel ignore the boot loader
2043 command line, and use ONLY the built-in command line.
2044
2045 This is used to work around broken boot loaders. This should
2046 be set to 'N' under normal conditions.
2047
2048 source "kernel/livepatch/Kconfig"
2049
2050 endmenu
2051
2052 config ARCH_ENABLE_MEMORY_HOTPLUG
2053 def_bool y
2054 depends on X86_64 || (X86_32 && HIGHMEM)
2055
2056 config ARCH_ENABLE_MEMORY_HOTREMOVE
2057 def_bool y
2058 depends on MEMORY_HOTPLUG
2059
2060 config USE_PERCPU_NUMA_NODE_ID
2061 def_bool y
2062 depends on NUMA
2063
2064 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2065 def_bool y
2066 depends on X86_64 || X86_PAE
2067
2068 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2069 def_bool y
2070 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2071
2072 menu "Power management and ACPI options"
2073
2074 config ARCH_HIBERNATION_HEADER
2075 def_bool y
2076 depends on X86_64 && HIBERNATION
2077
2078 source "kernel/power/Kconfig"
2079
2080 source "drivers/acpi/Kconfig"
2081
2082 source "drivers/sfi/Kconfig"
2083
2084 config X86_APM_BOOT
2085 def_bool y
2086 depends on APM
2087
2088 menuconfig APM
2089 tristate "APM (Advanced Power Management) BIOS support"
2090 depends on X86_32 && PM_SLEEP
2091 ---help---
2092 APM is a BIOS specification for saving power using several different
2093 techniques. This is mostly useful for battery powered laptops with
2094 APM compliant BIOSes. If you say Y here, the system time will be
2095 reset after a RESUME operation, the /proc/apm device will provide
2096 battery status information, and user-space programs will receive
2097 notification of APM "events" (e.g. battery status change).
2098
2099 If you select "Y" here, you can disable actual use of the APM
2100 BIOS by passing the "apm=off" option to the kernel at boot time.
2101
2102 Note that the APM support is almost completely disabled for
2103 machines with more than one CPU.
2104
2105 In order to use APM, you will need supporting software. For location
2106 and more information, read <file:Documentation/power/apm-acpi.txt>
2107 and the Battery Powered Linux mini-HOWTO, available from
2108 <http://www.tldp.org/docs.html#howto>.
2109
2110 This driver does not spin down disk drives (see the hdparm(8)
2111 manpage ("man 8 hdparm") for that), and it doesn't turn off
2112 VESA-compliant "green" monitors.
2113
2114 This driver does not support the TI 4000M TravelMate and the ACER
2115 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2116 desktop machines also don't have compliant BIOSes, and this driver
2117 may cause those machines to panic during the boot phase.
2118
2119 Generally, if you don't have a battery in your machine, there isn't
2120 much point in using this driver and you should say N. If you get
2121 random kernel OOPSes or reboots that don't seem to be related to
2122 anything, try disabling/enabling this option (or disabling/enabling
2123 APM in your BIOS).
2124
2125 Some other things you should try when experiencing seemingly random,
2126 "weird" problems:
2127
2128 1) make sure that you have enough swap space and that it is
2129 enabled.
2130 2) pass the "no-hlt" option to the kernel
2131 3) switch on floating point emulation in the kernel and pass
2132 the "no387" option to the kernel
2133 4) pass the "floppy=nodma" option to the kernel
2134 5) pass the "mem=4M" option to the kernel (thereby disabling
2135 all but the first 4 MB of RAM)
2136 6) make sure that the CPU is not over clocked.
2137 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2138 8) disable the cache from your BIOS settings
2139 9) install a fan for the video card or exchange video RAM
2140 10) install a better fan for the CPU
2141 11) exchange RAM chips
2142 12) exchange the motherboard.
2143
2144 To compile this driver as a module, choose M here: the
2145 module will be called apm.
2146
2147 if APM
2148
2149 config APM_IGNORE_USER_SUSPEND
2150 bool "Ignore USER SUSPEND"
2151 ---help---
2152 This option will ignore USER SUSPEND requests. On machines with a
2153 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2154 series notebooks, it is necessary to say Y because of a BIOS bug.
2155
2156 config APM_DO_ENABLE
2157 bool "Enable PM at boot time"
2158 ---help---
2159 Enable APM features at boot time. From page 36 of the APM BIOS
2160 specification: "When disabled, the APM BIOS does not automatically
2161 power manage devices, enter the Standby State, enter the Suspend
2162 State, or take power saving steps in response to CPU Idle calls."
2163 This driver will make CPU Idle calls when Linux is idle (unless this
2164 feature is turned off -- see "Do CPU IDLE calls", below). This
2165 should always save battery power, but more complicated APM features
2166 will be dependent on your BIOS implementation. You may need to turn
2167 this option off if your computer hangs at boot time when using APM
2168 support, or if it beeps continuously instead of suspending. Turn
2169 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2170 T400CDT. This is off by default since most machines do fine without
2171 this feature.
2172
2173 config APM_CPU_IDLE
2174 depends on CPU_IDLE
2175 bool "Make CPU Idle calls when idle"
2176 ---help---
2177 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2178 On some machines, this can activate improved power savings, such as
2179 a slowed CPU clock rate, when the machine is idle. These idle calls
2180 are made after the idle loop has run for some length of time (e.g.,
2181 333 mS). On some machines, this will cause a hang at boot time or
2182 whenever the CPU becomes idle. (On machines with more than one CPU,
2183 this option does nothing.)
2184
2185 config APM_DISPLAY_BLANK
2186 bool "Enable console blanking using APM"
2187 ---help---
2188 Enable console blanking using the APM. Some laptops can use this to
2189 turn off the LCD backlight when the screen blanker of the Linux
2190 virtual console blanks the screen. Note that this is only used by
2191 the virtual console screen blanker, and won't turn off the backlight
2192 when using the X Window system. This also doesn't have anything to
2193 do with your VESA-compliant power-saving monitor. Further, this
2194 option doesn't work for all laptops -- it might not turn off your
2195 backlight at all, or it might print a lot of errors to the console,
2196 especially if you are using gpm.
2197
2198 config APM_ALLOW_INTS
2199 bool "Allow interrupts during APM BIOS calls"
2200 ---help---
2201 Normally we disable external interrupts while we are making calls to
2202 the APM BIOS as a measure to lessen the effects of a badly behaving
2203 BIOS implementation. The BIOS should reenable interrupts if it
2204 needs to. Unfortunately, some BIOSes do not -- especially those in
2205 many of the newer IBM Thinkpads. If you experience hangs when you
2206 suspend, try setting this to Y. Otherwise, say N.
2207
2208 endif # APM
2209
2210 source "drivers/cpufreq/Kconfig"
2211
2212 source "drivers/cpuidle/Kconfig"
2213
2214 source "drivers/idle/Kconfig"
2215
2216 endmenu
2217
2218
2219 menu "Bus options (PCI etc.)"
2220
2221 config PCI
2222 bool "PCI support"
2223 default y
2224 ---help---
2225 Find out whether you have a PCI motherboard. PCI is the name of a
2226 bus system, i.e. the way the CPU talks to the other stuff inside
2227 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2228 VESA. If you have PCI, say Y, otherwise N.
2229
2230 choice
2231 prompt "PCI access mode"
2232 depends on X86_32 && PCI
2233 default PCI_GOANY
2234 ---help---
2235 On PCI systems, the BIOS can be used to detect the PCI devices and
2236 determine their configuration. However, some old PCI motherboards
2237 have BIOS bugs and may crash if this is done. Also, some embedded
2238 PCI-based systems don't have any BIOS at all. Linux can also try to
2239 detect the PCI hardware directly without using the BIOS.
2240
2241 With this option, you can specify how Linux should detect the
2242 PCI devices. If you choose "BIOS", the BIOS will be used,
2243 if you choose "Direct", the BIOS won't be used, and if you
2244 choose "MMConfig", then PCI Express MMCONFIG will be used.
2245 If you choose "Any", the kernel will try MMCONFIG, then the
2246 direct access method and falls back to the BIOS if that doesn't
2247 work. If unsure, go with the default, which is "Any".
2248
2249 config PCI_GOBIOS
2250 bool "BIOS"
2251
2252 config PCI_GOMMCONFIG
2253 bool "MMConfig"
2254
2255 config PCI_GODIRECT
2256 bool "Direct"
2257
2258 config PCI_GOOLPC
2259 bool "OLPC XO-1"
2260 depends on OLPC
2261
2262 config PCI_GOANY
2263 bool "Any"
2264
2265 endchoice
2266
2267 config PCI_BIOS
2268 def_bool y
2269 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2270
2271 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2272 config PCI_DIRECT
2273 def_bool y
2274 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2275
2276 config PCI_MMCONFIG
2277 def_bool y
2278 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2279
2280 config PCI_OLPC
2281 def_bool y
2282 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2283
2284 config PCI_XEN
2285 def_bool y
2286 depends on PCI && XEN
2287 select SWIOTLB_XEN
2288
2289 config PCI_DOMAINS
2290 def_bool y
2291 depends on PCI
2292
2293 config PCI_MMCONFIG
2294 bool "Support mmconfig PCI config space access"
2295 depends on X86_64 && PCI && ACPI
2296
2297 config PCI_CNB20LE_QUIRK
2298 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2299 depends on PCI
2300 help
2301 Read the PCI windows out of the CNB20LE host bridge. This allows
2302 PCI hotplug to work on systems with the CNB20LE chipset which do
2303 not have ACPI.
2304
2305 There's no public spec for this chipset, and this functionality
2306 is known to be incomplete.
2307
2308 You should say N unless you know you need this.
2309
2310 source "drivers/pci/pcie/Kconfig"
2311
2312 source "drivers/pci/Kconfig"
2313
2314 # x86_64 have no ISA slots, but can have ISA-style DMA.
2315 config ISA_DMA_API
2316 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2317 default y
2318 help
2319 Enables ISA-style DMA support for devices requiring such controllers.
2320 If unsure, say Y.
2321
2322 if X86_32
2323
2324 config ISA
2325 bool "ISA support"
2326 ---help---
2327 Find out whether you have ISA slots on your motherboard. ISA is the
2328 name of a bus system, i.e. the way the CPU talks to the other stuff
2329 inside your box. Other bus systems are PCI, EISA, MicroChannel
2330 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2331 newer boards don't support it. If you have ISA, say Y, otherwise N.
2332
2333 config EISA
2334 bool "EISA support"
2335 depends on ISA
2336 ---help---
2337 The Extended Industry Standard Architecture (EISA) bus was
2338 developed as an open alternative to the IBM MicroChannel bus.
2339
2340 The EISA bus provided some of the features of the IBM MicroChannel
2341 bus while maintaining backward compatibility with cards made for
2342 the older ISA bus. The EISA bus saw limited use between 1988 and
2343 1995 when it was made obsolete by the PCI bus.
2344
2345 Say Y here if you are building a kernel for an EISA-based machine.
2346
2347 Otherwise, say N.
2348
2349 source "drivers/eisa/Kconfig"
2350
2351 config SCx200
2352 tristate "NatSemi SCx200 support"
2353 ---help---
2354 This provides basic support for National Semiconductor's
2355 (now AMD's) Geode processors. The driver probes for the
2356 PCI-IDs of several on-chip devices, so its a good dependency
2357 for other scx200_* drivers.
2358
2359 If compiled as a module, the driver is named scx200.
2360
2361 config SCx200HR_TIMER
2362 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2363 depends on SCx200
2364 default y
2365 ---help---
2366 This driver provides a clocksource built upon the on-chip
2367 27MHz high-resolution timer. Its also a workaround for
2368 NSC Geode SC-1100's buggy TSC, which loses time when the
2369 processor goes idle (as is done by the scheduler). The
2370 other workaround is idle=poll boot option.
2371
2372 config OLPC
2373 bool "One Laptop Per Child support"
2374 depends on !X86_PAE
2375 select GPIOLIB
2376 select OF
2377 select OF_PROMTREE
2378 select IRQ_DOMAIN
2379 ---help---
2380 Add support for detecting the unique features of the OLPC
2381 XO hardware.
2382
2383 config OLPC_XO1_PM
2384 bool "OLPC XO-1 Power Management"
2385 depends on OLPC && MFD_CS5535 && PM_SLEEP
2386 select MFD_CORE
2387 ---help---
2388 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2389
2390 config OLPC_XO1_RTC
2391 bool "OLPC XO-1 Real Time Clock"
2392 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2393 ---help---
2394 Add support for the XO-1 real time clock, which can be used as a
2395 programmable wakeup source.
2396
2397 config OLPC_XO1_SCI
2398 bool "OLPC XO-1 SCI extras"
2399 depends on OLPC && OLPC_XO1_PM
2400 depends on INPUT=y
2401 select POWER_SUPPLY
2402 select GPIO_CS5535
2403 select MFD_CORE
2404 ---help---
2405 Add support for SCI-based features of the OLPC XO-1 laptop:
2406 - EC-driven system wakeups
2407 - Power button
2408 - Ebook switch
2409 - Lid switch
2410 - AC adapter status updates
2411 - Battery status updates
2412
2413 config OLPC_XO15_SCI
2414 bool "OLPC XO-1.5 SCI extras"
2415 depends on OLPC && ACPI
2416 select POWER_SUPPLY
2417 ---help---
2418 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2419 - EC-driven system wakeups
2420 - AC adapter status updates
2421 - Battery status updates
2422
2423 config ALIX
2424 bool "PCEngines ALIX System Support (LED setup)"
2425 select GPIOLIB
2426 ---help---
2427 This option enables system support for the PCEngines ALIX.
2428 At present this just sets up LEDs for GPIO control on
2429 ALIX2/3/6 boards. However, other system specific setup should
2430 get added here.
2431
2432 Note: You must still enable the drivers for GPIO and LED support
2433 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2434
2435 Note: You have to set alix.force=1 for boards with Award BIOS.
2436
2437 config NET5501
2438 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2439 select GPIOLIB
2440 ---help---
2441 This option enables system support for the Soekris Engineering net5501.
2442
2443 config GEOS
2444 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2445 select GPIOLIB
2446 depends on DMI
2447 ---help---
2448 This option enables system support for the Traverse Technologies GEOS.
2449
2450 config TS5500
2451 bool "Technologic Systems TS-5500 platform support"
2452 depends on MELAN
2453 select CHECK_SIGNATURE
2454 select NEW_LEDS
2455 select LEDS_CLASS
2456 ---help---
2457 This option enables system support for the Technologic Systems TS-5500.
2458
2459 endif # X86_32
2460
2461 config AMD_NB
2462 def_bool y
2463 depends on CPU_SUP_AMD && PCI
2464
2465 source "drivers/pcmcia/Kconfig"
2466
2467 source "drivers/pci/hotplug/Kconfig"
2468
2469 config RAPIDIO
2470 tristate "RapidIO support"
2471 depends on PCI
2472 default n
2473 help
2474 If enabled this option will include drivers and the core
2475 infrastructure code to support RapidIO interconnect devices.
2476
2477 source "drivers/rapidio/Kconfig"
2478
2479 config X86_SYSFB
2480 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2481 help
2482 Firmwares often provide initial graphics framebuffers so the BIOS,
2483 bootloader or kernel can show basic video-output during boot for
2484 user-guidance and debugging. Historically, x86 used the VESA BIOS
2485 Extensions and EFI-framebuffers for this, which are mostly limited
2486 to x86.
2487 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2488 framebuffers so the new generic system-framebuffer drivers can be
2489 used on x86. If the framebuffer is not compatible with the generic
2490 modes, it is adverticed as fallback platform framebuffer so legacy
2491 drivers like efifb, vesafb and uvesafb can pick it up.
2492 If this option is not selected, all system framebuffers are always
2493 marked as fallback platform framebuffers as usual.
2494
2495 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2496 not be able to pick up generic system framebuffers if this option
2497 is selected. You are highly encouraged to enable simplefb as
2498 replacement if you select this option. simplefb can correctly deal
2499 with generic system framebuffers. But you should still keep vesafb
2500 and others enabled as fallback if a system framebuffer is
2501 incompatible with simplefb.
2502
2503 If unsure, say Y.
2504
2505 endmenu
2506
2507
2508 menu "Executable file formats / Emulations"
2509
2510 source "fs/Kconfig.binfmt"
2511
2512 config IA32_EMULATION
2513 bool "IA32 Emulation"
2514 depends on X86_64
2515 select BINFMT_ELF
2516 select COMPAT_BINFMT_ELF
2517 select HAVE_UID16
2518 ---help---
2519 Include code to run legacy 32-bit programs under a
2520 64-bit kernel. You should likely turn this on, unless you're
2521 100% sure that you don't have any 32-bit programs left.
2522
2523 config IA32_AOUT
2524 tristate "IA32 a.out support"
2525 depends on IA32_EMULATION
2526 ---help---
2527 Support old a.out binaries in the 32bit emulation.
2528
2529 config X86_X32
2530 bool "x32 ABI for 64-bit mode"
2531 depends on X86_64 && IA32_EMULATION
2532 ---help---
2533 Include code to run binaries for the x32 native 32-bit ABI
2534 for 64-bit processors. An x32 process gets access to the
2535 full 64-bit register file and wide data path while leaving
2536 pointers at 32 bits for smaller memory footprint.
2537
2538 You will need a recent binutils (2.22 or later) with
2539 elf32_x86_64 support enabled to compile a kernel with this
2540 option set.
2541
2542 config COMPAT
2543 def_bool y
2544 depends on IA32_EMULATION || X86_X32
2545 select ARCH_WANT_OLD_COMPAT_IPC
2546
2547 if COMPAT
2548 config COMPAT_FOR_U64_ALIGNMENT
2549 def_bool y
2550
2551 config SYSVIPC_COMPAT
2552 def_bool y
2553 depends on SYSVIPC
2554
2555 config KEYS_COMPAT
2556 def_bool y
2557 depends on KEYS
2558 endif
2559
2560 endmenu
2561
2562
2563 config HAVE_ATOMIC_IOMAP
2564 def_bool y
2565 depends on X86_32
2566
2567 config X86_DEV_DMA_OPS
2568 bool
2569 depends on X86_64 || STA2X11
2570
2571 config X86_DMA_REMAP
2572 bool
2573 depends on STA2X11
2574
2575 config PMC_ATOM
2576 def_bool y
2577 depends on PCI
2578
2579 source "net/Kconfig"
2580
2581 source "drivers/Kconfig"
2582
2583 source "drivers/firmware/Kconfig"
2584
2585 source "fs/Kconfig"
2586
2587 source "arch/x86/Kconfig.debug"
2588
2589 source "security/Kconfig"
2590
2591 source "crypto/Kconfig"
2592
2593 source "arch/x86/kvm/Kconfig"
2594
2595 source "lib/Kconfig"