xref: /openbmc/linux/arch/x86/Kconfig (revision d774a589)
1# Select 32 or 64 bit
2config 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
9config X86_32
10	def_bool y
11	depends on !64BIT
12	# Options that are inherently 32-bit kernel only:
13	select ARCH_WANT_IPC_PARSE_VERSION
14	select CLKSRC_I8253
15	select CLONE_BACKWARDS
16	select HAVE_AOUT
17	select HAVE_GENERIC_DMA_COHERENT
18	select MODULES_USE_ELF_REL
19	select OLD_SIGACTION
20
21config X86_64
22	def_bool y
23	depends on 64BIT
24	# Options that are inherently 64-bit kernel only:
25	select ARCH_HAS_GIGANTIC_PAGE
26	select ARCH_SUPPORTS_INT128
27	select ARCH_USE_CMPXCHG_LOCKREF
28	select HAVE_ARCH_SOFT_DIRTY
29	select MODULES_USE_ELF_RELA
30	select X86_DEV_DMA_OPS
31
32#
33# Arch settings
34#
35# ( Note that options that are marked 'if X86_64' could in principle be
36#   ported to 32-bit as well. )
37#
38config X86
39	def_bool y
40	#
41	# Note: keep this list sorted alphabetically
42	#
43	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
44	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
45	select ANON_INODES
46	select ARCH_CLOCKSOURCE_DATA
47	select ARCH_DISCARD_MEMBLOCK
48	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
49	select ARCH_HAS_DEVMEM_IS_ALLOWED
50	select ARCH_HAS_ELF_RANDOMIZE
51	select ARCH_HAS_FAST_MULTIPLIER
52	select ARCH_HAS_GCOV_PROFILE_ALL
53	select ARCH_HAS_KCOV			if X86_64
54	select ARCH_HAS_MMIO_FLUSH
55	select ARCH_HAS_PMEM_API		if X86_64
56	select ARCH_HAS_SG_CHAIN
57	select ARCH_HAS_UBSAN_SANITIZE_ALL
58	select ARCH_HAVE_NMI_SAFE_CMPXCHG
59	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
60	select ARCH_MIGHT_HAVE_PC_PARPORT
61	select ARCH_MIGHT_HAVE_PC_SERIO
62	select ARCH_SUPPORTS_ATOMIC_RMW
63	select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
64	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
65	select ARCH_USE_BUILTIN_BSWAP
66	select ARCH_USE_QUEUED_RWLOCKS
67	select ARCH_USE_QUEUED_SPINLOCKS
68	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
69	select ARCH_WANT_FRAME_POINTERS
70	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
71	select BUILDTIME_EXTABLE_SORT
72	select CLKEVT_I8253
73	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
74	select CLOCKSOURCE_WATCHDOG
75	select DCACHE_WORD_ACCESS
76	select EDAC_ATOMIC_SCRUB
77	select EDAC_SUPPORT
78	select GENERIC_CLOCKEVENTS
79	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
80	select GENERIC_CLOCKEVENTS_MIN_ADJUST
81	select GENERIC_CMOS_UPDATE
82	select GENERIC_CPU_AUTOPROBE
83	select GENERIC_EARLY_IOREMAP
84	select GENERIC_FIND_FIRST_BIT
85	select GENERIC_IOMAP
86	select GENERIC_IRQ_PROBE
87	select GENERIC_IRQ_SHOW
88	select GENERIC_PENDING_IRQ		if SMP
89	select GENERIC_SMP_IDLE_THREAD
90	select GENERIC_STRNCPY_FROM_USER
91	select GENERIC_STRNLEN_USER
92	select GENERIC_TIME_VSYSCALL
93	select HAVE_ACPI_APEI			if ACPI
94	select HAVE_ACPI_APEI_NMI		if ACPI
95	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
96	select HAVE_ARCH_AUDITSYSCALL
97	select HAVE_ARCH_HARDENED_USERCOPY
98	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
99	select HAVE_ARCH_JUMP_LABEL
100	select HAVE_ARCH_KASAN			if X86_64 && SPARSEMEM_VMEMMAP
101	select HAVE_ARCH_KGDB
102	select HAVE_ARCH_KMEMCHECK
103	select HAVE_ARCH_MMAP_RND_BITS		if MMU
104	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
105	select HAVE_ARCH_SECCOMP_FILTER
106	select HAVE_ARCH_TRACEHOOK
107	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
108	select HAVE_ARCH_VMAP_STACK		if X86_64
109	select HAVE_ARCH_WITHIN_STACK_FRAMES
110	select HAVE_CC_STACKPROTECTOR
111	select HAVE_CMPXCHG_DOUBLE
112	select HAVE_CMPXCHG_LOCAL
113	select HAVE_CONTEXT_TRACKING		if X86_64
114	select HAVE_COPY_THREAD_TLS
115	select HAVE_C_RECORDMCOUNT
116	select HAVE_DEBUG_KMEMLEAK
117	select HAVE_DEBUG_STACKOVERFLOW
118	select HAVE_DMA_API_DEBUG
119	select HAVE_DMA_CONTIGUOUS
120	select HAVE_DYNAMIC_FTRACE
121	select HAVE_DYNAMIC_FTRACE_WITH_REGS
122	select HAVE_EBPF_JIT			if X86_64
123	select HAVE_EFFICIENT_UNALIGNED_ACCESS
124	select HAVE_EXIT_THREAD
125	select HAVE_FENTRY			if X86_64
126	select HAVE_FTRACE_MCOUNT_RECORD
127	select HAVE_FUNCTION_GRAPH_TRACER
128	select HAVE_FUNCTION_TRACER
129	select HAVE_GCC_PLUGINS
130	select HAVE_HW_BREAKPOINT
131	select HAVE_IDE
132	select HAVE_IOREMAP_PROT
133	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
134	select HAVE_IRQ_TIME_ACCOUNTING
135	select HAVE_KERNEL_BZIP2
136	select HAVE_KERNEL_GZIP
137	select HAVE_KERNEL_LZ4
138	select HAVE_KERNEL_LZMA
139	select HAVE_KERNEL_LZO
140	select HAVE_KERNEL_XZ
141	select HAVE_KPROBES
142	select HAVE_KPROBES_ON_FTRACE
143	select HAVE_KRETPROBES
144	select HAVE_KVM
145	select HAVE_LIVEPATCH			if X86_64
146	select HAVE_MEMBLOCK
147	select HAVE_MEMBLOCK_NODE_MAP
148	select HAVE_MIXED_BREAKPOINTS_REGS
149	select HAVE_NMI
150	select HAVE_OPROFILE
151	select HAVE_OPTPROBES
152	select HAVE_PCSPKR_PLATFORM
153	select HAVE_PERF_EVENTS
154	select HAVE_PERF_EVENTS_NMI
155	select HAVE_PERF_REGS
156	select HAVE_PERF_USER_STACK_DUMP
157	select HAVE_REGS_AND_STACK_ACCESS_API
158	select HAVE_STACK_VALIDATION		if X86_64
159	select HAVE_SYSCALL_TRACEPOINTS
160	select HAVE_UNSTABLE_SCHED_CLOCK
161	select HAVE_USER_RETURN_NOTIFIER
162	select IRQ_FORCED_THREADING
163	select PERF_EVENTS
164	select RTC_LIB
165	select RTC_MC146818_LIB
166	select SPARSE_IRQ
167	select SRCU
168	select SYSCTL_EXCEPTION_TRACE
169	select THREAD_INFO_IN_TASK
170	select USER_STACKTRACE_SUPPORT
171	select VIRT_TO_BUS
172	select X86_FEATURE_NAMES		if PROC_FS
173
174config INSTRUCTION_DECODER
175	def_bool y
176	depends on KPROBES || PERF_EVENTS || UPROBES
177
178config OUTPUT_FORMAT
179	string
180	default "elf32-i386" if X86_32
181	default "elf64-x86-64" if X86_64
182
183config ARCH_DEFCONFIG
184	string
185	default "arch/x86/configs/i386_defconfig" if X86_32
186	default "arch/x86/configs/x86_64_defconfig" if X86_64
187
188config LOCKDEP_SUPPORT
189	def_bool y
190
191config STACKTRACE_SUPPORT
192	def_bool y
193
194config MMU
195	def_bool y
196
197config ARCH_MMAP_RND_BITS_MIN
198	default 28 if 64BIT
199	default 8
200
201config ARCH_MMAP_RND_BITS_MAX
202	default 32 if 64BIT
203	default 16
204
205config ARCH_MMAP_RND_COMPAT_BITS_MIN
206	default 8
207
208config ARCH_MMAP_RND_COMPAT_BITS_MAX
209	default 16
210
211config SBUS
212	bool
213
214config NEED_DMA_MAP_STATE
215	def_bool y
216	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
217
218config NEED_SG_DMA_LENGTH
219	def_bool y
220
221config GENERIC_ISA_DMA
222	def_bool y
223	depends on ISA_DMA_API
224
225config GENERIC_BUG
226	def_bool y
227	depends on BUG
228	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
229
230config GENERIC_BUG_RELATIVE_POINTERS
231	bool
232
233config GENERIC_HWEIGHT
234	def_bool y
235
236config ARCH_MAY_HAVE_PC_FDC
237	def_bool y
238	depends on ISA_DMA_API
239
240config RWSEM_XCHGADD_ALGORITHM
241	def_bool y
242
243config GENERIC_CALIBRATE_DELAY
244	def_bool y
245
246config ARCH_HAS_CPU_RELAX
247	def_bool y
248
249config ARCH_HAS_CACHE_LINE_SIZE
250	def_bool y
251
252config HAVE_SETUP_PER_CPU_AREA
253	def_bool y
254
255config NEED_PER_CPU_EMBED_FIRST_CHUNK
256	def_bool y
257
258config NEED_PER_CPU_PAGE_FIRST_CHUNK
259	def_bool y
260
261config ARCH_HIBERNATION_POSSIBLE
262	def_bool y
263
264config ARCH_SUSPEND_POSSIBLE
265	def_bool y
266
267config ARCH_WANT_HUGE_PMD_SHARE
268	def_bool y
269
270config ARCH_WANT_GENERAL_HUGETLB
271	def_bool y
272
273config ZONE_DMA32
274	def_bool y if X86_64
275
276config AUDIT_ARCH
277	def_bool y if X86_64
278
279config ARCH_SUPPORTS_OPTIMIZED_INLINING
280	def_bool y
281
282config ARCH_SUPPORTS_DEBUG_PAGEALLOC
283	def_bool y
284
285config KASAN_SHADOW_OFFSET
286	hex
287	depends on KASAN
288	default 0xdffffc0000000000
289
290config HAVE_INTEL_TXT
291	def_bool y
292	depends on INTEL_IOMMU && ACPI
293
294config X86_32_SMP
295	def_bool y
296	depends on X86_32 && SMP
297
298config X86_64_SMP
299	def_bool y
300	depends on X86_64 && SMP
301
302config X86_32_LAZY_GS
303	def_bool y
304	depends on X86_32 && !CC_STACKPROTECTOR
305
306config ARCH_SUPPORTS_UPROBES
307	def_bool y
308
309config FIX_EARLYCON_MEM
310	def_bool y
311
312config DEBUG_RODATA
313	def_bool y
314
315config PGTABLE_LEVELS
316	int
317	default 4 if X86_64
318	default 3 if X86_PAE
319	default 2
320
321source "init/Kconfig"
322source "kernel/Kconfig.freezer"
323
324menu "Processor type and features"
325
326config ZONE_DMA
327	bool "DMA memory allocation support" if EXPERT
328	default y
329	help
330	  DMA memory allocation support allows devices with less than 32-bit
331	  addressing to allocate within the first 16MB of address space.
332	  Disable if no such devices will be used.
333
334	  If unsure, say Y.
335
336config SMP
337	bool "Symmetric multi-processing support"
338	---help---
339	  This enables support for systems with more than one CPU. If you have
340	  a system with only one CPU, say N. If you have a system with more
341	  than one CPU, say Y.
342
343	  If you say N here, the kernel will run on uni- and multiprocessor
344	  machines, but will use only one CPU of a multiprocessor machine. If
345	  you say Y here, the kernel will run on many, but not all,
346	  uniprocessor machines. On a uniprocessor machine, the kernel
347	  will run faster if you say N here.
348
349	  Note that if you say Y here and choose architecture "586" or
350	  "Pentium" under "Processor family", the kernel will not work on 486
351	  architectures. Similarly, multiprocessor kernels for the "PPro"
352	  architecture may not work on all Pentium based boards.
353
354	  People using multiprocessor machines who say Y here should also say
355	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
356	  Management" code will be disabled if you say Y here.
357
358	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
359	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
360	  <http://www.tldp.org/docs.html#howto>.
361
362	  If you don't know what to do here, say N.
363
364config X86_FEATURE_NAMES
365	bool "Processor feature human-readable names" if EMBEDDED
366	default y
367	---help---
368	  This option compiles in a table of x86 feature bits and corresponding
369	  names.  This is required to support /proc/cpuinfo and a few kernel
370	  messages.  You can disable this to save space, at the expense of
371	  making those few kernel messages show numeric feature bits instead.
372
373	  If in doubt, say Y.
374
375config X86_FAST_FEATURE_TESTS
376	bool "Fast CPU feature tests" if EMBEDDED
377	default y
378	---help---
379	  Some fast-paths in the kernel depend on the capabilities of the CPU.
380	  Say Y here for the kernel to patch in the appropriate code at runtime
381	  based on the capabilities of the CPU. The infrastructure for patching
382	  code at runtime takes up some additional space; space-constrained
383	  embedded systems may wish to say N here to produce smaller, slightly
384	  slower code.
385
386config X86_X2APIC
387	bool "Support x2apic"
388	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
389	---help---
390	  This enables x2apic support on CPUs that have this feature.
391
392	  This allows 32-bit apic IDs (so it can support very large systems),
393	  and accesses the local apic via MSRs not via mmio.
394
395	  If you don't know what to do here, say N.
396
397config X86_MPPARSE
398	bool "Enable MPS table" if ACPI || SFI
399	default y
400	depends on X86_LOCAL_APIC
401	---help---
402	  For old smp systems that do not have proper acpi support. Newer systems
403	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
404
405config X86_BIGSMP
406	bool "Support for big SMP systems with more than 8 CPUs"
407	depends on X86_32 && SMP
408	---help---
409	  This option is needed for the systems that have more than 8 CPUs
410
411config GOLDFISH
412       def_bool y
413       depends on X86_GOLDFISH
414
415config INTEL_RDT_A
416	bool "Intel Resource Director Technology Allocation support"
417	default n
418	depends on X86 && CPU_SUP_INTEL
419	select KERNFS
420	help
421	  Select to enable resource allocation which is a sub-feature of
422	  Intel Resource Director Technology(RDT). More information about
423	  RDT can be found in the Intel x86 Architecture Software
424	  Developer Manual.
425
426	  Say N if unsure.
427
428if X86_32
429config X86_EXTENDED_PLATFORM
430	bool "Support for extended (non-PC) x86 platforms"
431	default y
432	---help---
433	  If you disable this option then the kernel will only support
434	  standard PC platforms. (which covers the vast majority of
435	  systems out there.)
436
437	  If you enable this option then you'll be able to select support
438	  for the following (non-PC) 32 bit x86 platforms:
439		Goldfish (Android emulator)
440		AMD Elan
441		RDC R-321x SoC
442		SGI 320/540 (Visual Workstation)
443		STA2X11-based (e.g. Northville)
444		Moorestown MID devices
445
446	  If you have one of these systems, or if you want to build a
447	  generic distribution kernel, say Y here - otherwise say N.
448endif
449
450if X86_64
451config X86_EXTENDED_PLATFORM
452	bool "Support for extended (non-PC) x86 platforms"
453	default y
454	---help---
455	  If you disable this option then the kernel will only support
456	  standard PC platforms. (which covers the vast majority of
457	  systems out there.)
458
459	  If you enable this option then you'll be able to select support
460	  for the following (non-PC) 64 bit x86 platforms:
461		Numascale NumaChip
462		ScaleMP vSMP
463		SGI Ultraviolet
464
465	  If you have one of these systems, or if you want to build a
466	  generic distribution kernel, say Y here - otherwise say N.
467endif
468# This is an alphabetically sorted list of 64 bit extended platforms
469# Please maintain the alphabetic order if and when there are additions
470config X86_NUMACHIP
471	bool "Numascale NumaChip"
472	depends on X86_64
473	depends on X86_EXTENDED_PLATFORM
474	depends on NUMA
475	depends on SMP
476	depends on X86_X2APIC
477	depends on PCI_MMCONFIG
478	---help---
479	  Adds support for Numascale NumaChip large-SMP systems. Needed to
480	  enable more than ~168 cores.
481	  If you don't have one of these, you should say N here.
482
483config X86_VSMP
484	bool "ScaleMP vSMP"
485	select HYPERVISOR_GUEST
486	select PARAVIRT
487	depends on X86_64 && PCI
488	depends on X86_EXTENDED_PLATFORM
489	depends on SMP
490	---help---
491	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
492	  supposed to run on these EM64T-based machines.  Only choose this option
493	  if you have one of these machines.
494
495config X86_UV
496	bool "SGI Ultraviolet"
497	depends on X86_64
498	depends on X86_EXTENDED_PLATFORM
499	depends on NUMA
500	depends on EFI
501	depends on X86_X2APIC
502	depends on PCI
503	---help---
504	  This option is needed in order to support SGI Ultraviolet systems.
505	  If you don't have one of these, you should say N here.
506
507# Following is an alphabetically sorted list of 32 bit extended platforms
508# Please maintain the alphabetic order if and when there are additions
509
510config X86_GOLDFISH
511       bool "Goldfish (Virtual Platform)"
512       depends on X86_EXTENDED_PLATFORM
513       ---help---
514	 Enable support for the Goldfish virtual platform used primarily
515	 for Android development. Unless you are building for the Android
516	 Goldfish emulator say N here.
517
518config X86_INTEL_CE
519	bool "CE4100 TV platform"
520	depends on PCI
521	depends on PCI_GODIRECT
522	depends on X86_IO_APIC
523	depends on X86_32
524	depends on X86_EXTENDED_PLATFORM
525	select X86_REBOOTFIXUPS
526	select OF
527	select OF_EARLY_FLATTREE
528	---help---
529	  Select for the Intel CE media processor (CE4100) SOC.
530	  This option compiles in support for the CE4100 SOC for settop
531	  boxes and media devices.
532
533config X86_INTEL_MID
534	bool "Intel MID platform support"
535	depends on X86_EXTENDED_PLATFORM
536	depends on X86_PLATFORM_DEVICES
537	depends on PCI
538	depends on X86_64 || (PCI_GOANY && X86_32)
539	depends on X86_IO_APIC
540	select SFI
541	select I2C
542	select DW_APB_TIMER
543	select APB_TIMER
544	select INTEL_SCU_IPC
545	select MFD_INTEL_MSIC
546	---help---
547	  Select to build a kernel capable of supporting Intel MID (Mobile
548	  Internet Device) platform systems which do not have the PCI legacy
549	  interfaces. If you are building for a PC class system say N here.
550
551	  Intel MID platforms are based on an Intel processor and chipset which
552	  consume less power than most of the x86 derivatives.
553
554config X86_INTEL_QUARK
555	bool "Intel Quark platform support"
556	depends on X86_32
557	depends on X86_EXTENDED_PLATFORM
558	depends on X86_PLATFORM_DEVICES
559	depends on X86_TSC
560	depends on PCI
561	depends on PCI_GOANY
562	depends on X86_IO_APIC
563	select IOSF_MBI
564	select INTEL_IMR
565	select COMMON_CLK
566	---help---
567	  Select to include support for Quark X1000 SoC.
568	  Say Y here if you have a Quark based system such as the Arduino
569	  compatible Intel Galileo.
570
571config X86_INTEL_LPSS
572	bool "Intel Low Power Subsystem Support"
573	depends on X86 && ACPI
574	select COMMON_CLK
575	select PINCTRL
576	select IOSF_MBI
577	---help---
578	  Select to build support for Intel Low Power Subsystem such as
579	  found on Intel Lynxpoint PCH. Selecting this option enables
580	  things like clock tree (common clock framework) and pincontrol
581	  which are needed by the LPSS peripheral drivers.
582
583config X86_AMD_PLATFORM_DEVICE
584	bool "AMD ACPI2Platform devices support"
585	depends on ACPI
586	select COMMON_CLK
587	select PINCTRL
588	---help---
589	  Select to interpret AMD specific ACPI device to platform device
590	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
591	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
592	  implemented under PINCTRL subsystem.
593
594config IOSF_MBI
595	tristate "Intel SoC IOSF Sideband support for SoC platforms"
596	depends on PCI
597	---help---
598	  This option enables sideband register access support for Intel SoC
599	  platforms. On these platforms the IOSF sideband is used in lieu of
600	  MSR's for some register accesses, mostly but not limited to thermal
601	  and power. Drivers may query the availability of this device to
602	  determine if they need the sideband in order to work on these
603	  platforms. The sideband is available on the following SoC products.
604	  This list is not meant to be exclusive.
605	   - BayTrail
606	   - Braswell
607	   - Quark
608
609	  You should say Y if you are running a kernel on one of these SoC's.
610
611config IOSF_MBI_DEBUG
612	bool "Enable IOSF sideband access through debugfs"
613	depends on IOSF_MBI && DEBUG_FS
614	---help---
615	  Select this option to expose the IOSF sideband access registers (MCR,
616	  MDR, MCRX) through debugfs to write and read register information from
617	  different units on the SoC. This is most useful for obtaining device
618	  state information for debug and analysis. As this is a general access
619	  mechanism, users of this option would have specific knowledge of the
620	  device they want to access.
621
622	  If you don't require the option or are in doubt, say N.
623
624config X86_RDC321X
625	bool "RDC R-321x SoC"
626	depends on X86_32
627	depends on X86_EXTENDED_PLATFORM
628	select M486
629	select X86_REBOOTFIXUPS
630	---help---
631	  This option is needed for RDC R-321x system-on-chip, also known
632	  as R-8610-(G).
633	  If you don't have one of these chips, you should say N here.
634
635config X86_32_NON_STANDARD
636	bool "Support non-standard 32-bit SMP architectures"
637	depends on X86_32 && SMP
638	depends on X86_EXTENDED_PLATFORM
639	---help---
640	  This option compiles in the bigsmp and STA2X11 default
641	  subarchitectures.  It is intended for a generic binary
642	  kernel. If you select them all, kernel will probe it one by
643	  one and will fallback to default.
644
645# Alphabetically sorted list of Non standard 32 bit platforms
646
647config X86_SUPPORTS_MEMORY_FAILURE
648	def_bool y
649	# MCE code calls memory_failure():
650	depends on X86_MCE
651	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
652	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
653	depends on X86_64 || !SPARSEMEM
654	select ARCH_SUPPORTS_MEMORY_FAILURE
655
656config STA2X11
657	bool "STA2X11 Companion Chip Support"
658	depends on X86_32_NON_STANDARD && PCI
659	select X86_DEV_DMA_OPS
660	select X86_DMA_REMAP
661	select SWIOTLB
662	select MFD_STA2X11
663	select GPIOLIB
664	default n
665	---help---
666	  This adds support for boards based on the STA2X11 IO-Hub,
667	  a.k.a. "ConneXt". The chip is used in place of the standard
668	  PC chipset, so all "standard" peripherals are missing. If this
669	  option is selected the kernel will still be able to boot on
670	  standard PC machines.
671
672config X86_32_IRIS
673	tristate "Eurobraille/Iris poweroff module"
674	depends on X86_32
675	---help---
676	  The Iris machines from EuroBraille do not have APM or ACPI support
677	  to shut themselves down properly.  A special I/O sequence is
678	  needed to do so, which is what this module does at
679	  kernel shutdown.
680
681	  This is only for Iris machines from EuroBraille.
682
683	  If unused, say N.
684
685config SCHED_OMIT_FRAME_POINTER
686	def_bool y
687	prompt "Single-depth WCHAN output"
688	depends on X86
689	---help---
690	  Calculate simpler /proc/<PID>/wchan values. If this option
691	  is disabled then wchan values will recurse back to the
692	  caller function. This provides more accurate wchan values,
693	  at the expense of slightly more scheduling overhead.
694
695	  If in doubt, say "Y".
696
697menuconfig HYPERVISOR_GUEST
698	bool "Linux guest support"
699	---help---
700	  Say Y here to enable options for running Linux under various hyper-
701	  visors. This option enables basic hypervisor detection and platform
702	  setup.
703
704	  If you say N, all options in this submenu will be skipped and
705	  disabled, and Linux guest support won't be built in.
706
707if HYPERVISOR_GUEST
708
709config PARAVIRT
710	bool "Enable paravirtualization code"
711	---help---
712	  This changes the kernel so it can modify itself when it is run
713	  under a hypervisor, potentially improving performance significantly
714	  over full virtualization.  However, when run without a hypervisor
715	  the kernel is theoretically slower and slightly larger.
716
717config PARAVIRT_DEBUG
718	bool "paravirt-ops debugging"
719	depends on PARAVIRT && DEBUG_KERNEL
720	---help---
721	  Enable to debug paravirt_ops internals.  Specifically, BUG if
722	  a paravirt_op is missing when it is called.
723
724config PARAVIRT_SPINLOCKS
725	bool "Paravirtualization layer for spinlocks"
726	depends on PARAVIRT && SMP
727	---help---
728	  Paravirtualized spinlocks allow a pvops backend to replace the
729	  spinlock implementation with something virtualization-friendly
730	  (for example, block the virtual CPU rather than spinning).
731
732	  It has a minimal impact on native kernels and gives a nice performance
733	  benefit on paravirtualized KVM / Xen kernels.
734
735	  If you are unsure how to answer this question, answer Y.
736
737config QUEUED_LOCK_STAT
738	bool "Paravirt queued spinlock statistics"
739	depends on PARAVIRT_SPINLOCKS && DEBUG_FS
740	---help---
741	  Enable the collection of statistical data on the slowpath
742	  behavior of paravirtualized queued spinlocks and report
743	  them on debugfs.
744
745source "arch/x86/xen/Kconfig"
746
747config KVM_GUEST
748	bool "KVM Guest support (including kvmclock)"
749	depends on PARAVIRT
750	select PARAVIRT_CLOCK
751	default y
752	---help---
753	  This option enables various optimizations for running under the KVM
754	  hypervisor. It includes a paravirtualized clock, so that instead
755	  of relying on a PIT (or probably other) emulation by the
756	  underlying device model, the host provides the guest with
757	  timing infrastructure such as time of day, and system time
758
759config KVM_DEBUG_FS
760	bool "Enable debug information for KVM Guests in debugfs"
761	depends on KVM_GUEST && DEBUG_FS
762	default n
763	---help---
764	  This option enables collection of various statistics for KVM guest.
765	  Statistics are displayed in debugfs filesystem. Enabling this option
766	  may incur significant overhead.
767
768source "arch/x86/lguest/Kconfig"
769
770config PARAVIRT_TIME_ACCOUNTING
771	bool "Paravirtual steal time accounting"
772	depends on PARAVIRT
773	default n
774	---help---
775	  Select this option to enable fine granularity task steal time
776	  accounting. Time spent executing other tasks in parallel with
777	  the current vCPU is discounted from the vCPU power. To account for
778	  that, there can be a small performance impact.
779
780	  If in doubt, say N here.
781
782config PARAVIRT_CLOCK
783	bool
784
785endif #HYPERVISOR_GUEST
786
787config NO_BOOTMEM
788	def_bool y
789
790source "arch/x86/Kconfig.cpu"
791
792config HPET_TIMER
793	def_bool X86_64
794	prompt "HPET Timer Support" if X86_32
795	---help---
796	  Use the IA-PC HPET (High Precision Event Timer) to manage
797	  time in preference to the PIT and RTC, if a HPET is
798	  present.
799	  HPET is the next generation timer replacing legacy 8254s.
800	  The HPET provides a stable time base on SMP
801	  systems, unlike the TSC, but it is more expensive to access,
802	  as it is off-chip.  The interface used is documented
803	  in the HPET spec, revision 1.
804
805	  You can safely choose Y here.  However, HPET will only be
806	  activated if the platform and the BIOS support this feature.
807	  Otherwise the 8254 will be used for timing services.
808
809	  Choose N to continue using the legacy 8254 timer.
810
811config HPET_EMULATE_RTC
812	def_bool y
813	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
814
815config APB_TIMER
816       def_bool y if X86_INTEL_MID
817       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
818       select DW_APB_TIMER
819       depends on X86_INTEL_MID && SFI
820       help
821         APB timer is the replacement for 8254, HPET on X86 MID platforms.
822         The APBT provides a stable time base on SMP
823         systems, unlike the TSC, but it is more expensive to access,
824         as it is off-chip. APB timers are always running regardless of CPU
825         C states, they are used as per CPU clockevent device when possible.
826
827# Mark as expert because too many people got it wrong.
828# The code disables itself when not needed.
829config DMI
830	default y
831	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
832	bool "Enable DMI scanning" if EXPERT
833	---help---
834	  Enabled scanning of DMI to identify machine quirks. Say Y
835	  here unless you have verified that your setup is not
836	  affected by entries in the DMI blacklist. Required by PNP
837	  BIOS code.
838
839config GART_IOMMU
840	bool "Old AMD GART IOMMU support"
841	select SWIOTLB
842	depends on X86_64 && PCI && AMD_NB
843	---help---
844	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
845	  GART based hardware IOMMUs.
846
847	  The GART supports full DMA access for devices with 32-bit access
848	  limitations, on systems with more than 3 GB. This is usually needed
849	  for USB, sound, many IDE/SATA chipsets and some other devices.
850
851	  Newer systems typically have a modern AMD IOMMU, supported via
852	  the CONFIG_AMD_IOMMU=y config option.
853
854	  In normal configurations this driver is only active when needed:
855	  there's more than 3 GB of memory and the system contains a
856	  32-bit limited device.
857
858	  If unsure, say Y.
859
860config CALGARY_IOMMU
861	bool "IBM Calgary IOMMU support"
862	select SWIOTLB
863	depends on X86_64 && PCI
864	---help---
865	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
866	  systems. Needed to run systems with more than 3GB of memory
867	  properly with 32-bit PCI devices that do not support DAC
868	  (Double Address Cycle). Calgary also supports bus level
869	  isolation, where all DMAs pass through the IOMMU.  This
870	  prevents them from going anywhere except their intended
871	  destination. This catches hard-to-find kernel bugs and
872	  mis-behaving drivers and devices that do not use the DMA-API
873	  properly to set up their DMA buffers.  The IOMMU can be
874	  turned off at boot time with the iommu=off parameter.
875	  Normally the kernel will make the right choice by itself.
876	  If unsure, say Y.
877
878config CALGARY_IOMMU_ENABLED_BY_DEFAULT
879	def_bool y
880	prompt "Should Calgary be enabled by default?"
881	depends on CALGARY_IOMMU
882	---help---
883	  Should Calgary be enabled by default? if you choose 'y', Calgary
884	  will be used (if it exists). If you choose 'n', Calgary will not be
885	  used even if it exists. If you choose 'n' and would like to use
886	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
887	  If unsure, say Y.
888
889# need this always selected by IOMMU for the VIA workaround
890config SWIOTLB
891	def_bool y if X86_64
892	---help---
893	  Support for software bounce buffers used on x86-64 systems
894	  which don't have a hardware IOMMU. Using this PCI devices
895	  which can only access 32-bits of memory can be used on systems
896	  with more than 3 GB of memory.
897	  If unsure, say Y.
898
899config IOMMU_HELPER
900	def_bool y
901	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
902
903config MAXSMP
904	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
905	depends on X86_64 && SMP && DEBUG_KERNEL
906	select CPUMASK_OFFSTACK
907	---help---
908	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
909	  If unsure, say N.
910
911config NR_CPUS
912	int "Maximum number of CPUs" if SMP && !MAXSMP
913	range 2 8 if SMP && X86_32 && !X86_BIGSMP
914	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
915	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
916	default "1" if !SMP
917	default "8192" if MAXSMP
918	default "32" if SMP && X86_BIGSMP
919	default "8" if SMP && X86_32
920	default "64" if SMP
921	---help---
922	  This allows you to specify the maximum number of CPUs which this
923	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
924	  supported value is 8192, otherwise the maximum value is 512.  The
925	  minimum value which makes sense is 2.
926
927	  This is purely to save memory - each supported CPU adds
928	  approximately eight kilobytes to the kernel image.
929
930config SCHED_SMT
931	bool "SMT (Hyperthreading) scheduler support"
932	depends on SMP
933	---help---
934	  SMT scheduler support improves the CPU scheduler's decision making
935	  when dealing with Intel Pentium 4 chips with HyperThreading at a
936	  cost of slightly increased overhead in some places. If unsure say
937	  N here.
938
939config SCHED_MC
940	def_bool y
941	prompt "Multi-core scheduler support"
942	depends on SMP
943	---help---
944	  Multi-core scheduler support improves the CPU scheduler's decision
945	  making when dealing with multi-core CPU chips at a cost of slightly
946	  increased overhead in some places. If unsure say N here.
947
948config SCHED_MC_PRIO
949	bool "CPU core priorities scheduler support"
950	depends on SCHED_MC && CPU_SUP_INTEL
951	select X86_INTEL_PSTATE
952	select CPU_FREQ
953	default y
954	---help---
955	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
956	  core ordering determined at manufacturing time, which allows
957	  certain cores to reach higher turbo frequencies (when running
958	  single threaded workloads) than others.
959
960	  Enabling this kernel feature teaches the scheduler about
961	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
962	  scheduler's CPU selection logic accordingly, so that higher
963	  overall system performance can be achieved.
964
965	  This feature will have no effect on CPUs without this feature.
966
967	  If unsure say Y here.
968
969source "kernel/Kconfig.preempt"
970
971config UP_LATE_INIT
972       def_bool y
973       depends on !SMP && X86_LOCAL_APIC
974
975config X86_UP_APIC
976	bool "Local APIC support on uniprocessors" if !PCI_MSI
977	default PCI_MSI
978	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
979	---help---
980	  A local APIC (Advanced Programmable Interrupt Controller) is an
981	  integrated interrupt controller in the CPU. If you have a single-CPU
982	  system which has a processor with a local APIC, you can say Y here to
983	  enable and use it. If you say Y here even though your machine doesn't
984	  have a local APIC, then the kernel will still run with no slowdown at
985	  all. The local APIC supports CPU-generated self-interrupts (timer,
986	  performance counters), and the NMI watchdog which detects hard
987	  lockups.
988
989config X86_UP_IOAPIC
990	bool "IO-APIC support on uniprocessors"
991	depends on X86_UP_APIC
992	---help---
993	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
994	  SMP-capable replacement for PC-style interrupt controllers. Most
995	  SMP systems and many recent uniprocessor systems have one.
996
997	  If you have a single-CPU system with an IO-APIC, you can say Y here
998	  to use it. If you say Y here even though your machine doesn't have
999	  an IO-APIC, then the kernel will still run with no slowdown at all.
1000
1001config X86_LOCAL_APIC
1002	def_bool y
1003	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1004	select IRQ_DOMAIN_HIERARCHY
1005	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
1006
1007config X86_IO_APIC
1008	def_bool y
1009	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1010
1011config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1012	bool "Reroute for broken boot IRQs"
1013	depends on X86_IO_APIC
1014	---help---
1015	  This option enables a workaround that fixes a source of
1016	  spurious interrupts. This is recommended when threaded
1017	  interrupt handling is used on systems where the generation of
1018	  superfluous "boot interrupts" cannot be disabled.
1019
1020	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1021	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
1022	  kernel does during interrupt handling). On chipsets where this
1023	  boot IRQ generation cannot be disabled, this workaround keeps
1024	  the original IRQ line masked so that only the equivalent "boot
1025	  IRQ" is delivered to the CPUs. The workaround also tells the
1026	  kernel to set up the IRQ handler on the boot IRQ line. In this
1027	  way only one interrupt is delivered to the kernel. Otherwise
1028	  the spurious second interrupt may cause the kernel to bring
1029	  down (vital) interrupt lines.
1030
1031	  Only affects "broken" chipsets. Interrupt sharing may be
1032	  increased on these systems.
1033
1034config X86_MCE
1035	bool "Machine Check / overheating reporting"
1036	select GENERIC_ALLOCATOR
1037	default y
1038	---help---
1039	  Machine Check support allows the processor to notify the
1040	  kernel if it detects a problem (e.g. overheating, data corruption).
1041	  The action the kernel takes depends on the severity of the problem,
1042	  ranging from warning messages to halting the machine.
1043
1044config X86_MCE_INTEL
1045	def_bool y
1046	prompt "Intel MCE features"
1047	depends on X86_MCE && X86_LOCAL_APIC
1048	---help---
1049	   Additional support for intel specific MCE features such as
1050	   the thermal monitor.
1051
1052config X86_MCE_AMD
1053	def_bool y
1054	prompt "AMD MCE features"
1055	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
1056	---help---
1057	   Additional support for AMD specific MCE features such as
1058	   the DRAM Error Threshold.
1059
1060config X86_ANCIENT_MCE
1061	bool "Support for old Pentium 5 / WinChip machine checks"
1062	depends on X86_32 && X86_MCE
1063	---help---
1064	  Include support for machine check handling on old Pentium 5 or WinChip
1065	  systems. These typically need to be enabled explicitly on the command
1066	  line.
1067
1068config X86_MCE_THRESHOLD
1069	depends on X86_MCE_AMD || X86_MCE_INTEL
1070	def_bool y
1071
1072config X86_MCE_INJECT
1073	depends on X86_MCE
1074	tristate "Machine check injector support"
1075	---help---
1076	  Provide support for injecting machine checks for testing purposes.
1077	  If you don't know what a machine check is and you don't do kernel
1078	  QA it is safe to say n.
1079
1080config X86_THERMAL_VECTOR
1081	def_bool y
1082	depends on X86_MCE_INTEL
1083
1084source "arch/x86/events/Kconfig"
1085
1086config X86_LEGACY_VM86
1087	bool "Legacy VM86 support"
1088	default n
1089	depends on X86_32
1090	---help---
1091	  This option allows user programs to put the CPU into V8086
1092	  mode, which is an 80286-era approximation of 16-bit real mode.
1093
1094	  Some very old versions of X and/or vbetool require this option
1095	  for user mode setting.  Similarly, DOSEMU will use it if
1096	  available to accelerate real mode DOS programs.  However, any
1097	  recent version of DOSEMU, X, or vbetool should be fully
1098	  functional even without kernel VM86 support, as they will all
1099	  fall back to software emulation. Nevertheless, if you are using
1100	  a 16-bit DOS program where 16-bit performance matters, vm86
1101	  mode might be faster than emulation and you might want to
1102	  enable this option.
1103
1104	  Note that any app that works on a 64-bit kernel is unlikely to
1105	  need this option, as 64-bit kernels don't, and can't, support
1106	  V8086 mode. This option is also unrelated to 16-bit protected
1107	  mode and is not needed to run most 16-bit programs under Wine.
1108
1109	  Enabling this option increases the complexity of the kernel
1110	  and slows down exception handling a tiny bit.
1111
1112	  If unsure, say N here.
1113
1114config VM86
1115       bool
1116       default X86_LEGACY_VM86
1117
1118config X86_16BIT
1119	bool "Enable support for 16-bit segments" if EXPERT
1120	default y
1121	depends on MODIFY_LDT_SYSCALL
1122	---help---
1123	  This option is required by programs like Wine to run 16-bit
1124	  protected mode legacy code on x86 processors.  Disabling
1125	  this option saves about 300 bytes on i386, or around 6K text
1126	  plus 16K runtime memory on x86-64,
1127
1128config X86_ESPFIX32
1129	def_bool y
1130	depends on X86_16BIT && X86_32
1131
1132config X86_ESPFIX64
1133	def_bool y
1134	depends on X86_16BIT && X86_64
1135
1136config X86_VSYSCALL_EMULATION
1137       bool "Enable vsyscall emulation" if EXPERT
1138       default y
1139       depends on X86_64
1140       ---help---
1141	 This enables emulation of the legacy vsyscall page.  Disabling
1142	 it is roughly equivalent to booting with vsyscall=none, except
1143	 that it will also disable the helpful warning if a program
1144	 tries to use a vsyscall.  With this option set to N, offending
1145	 programs will just segfault, citing addresses of the form
1146	 0xffffffffff600?00.
1147
1148	 This option is required by many programs built before 2013, and
1149	 care should be used even with newer programs if set to N.
1150
1151	 Disabling this option saves about 7K of kernel size and
1152	 possibly 4K of additional runtime pagetable memory.
1153
1154config TOSHIBA
1155	tristate "Toshiba Laptop support"
1156	depends on X86_32
1157	---help---
1158	  This adds a driver to safely access the System Management Mode of
1159	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1160	  not work on models with a Phoenix BIOS. The System Management Mode
1161	  is used to set the BIOS and power saving options on Toshiba portables.
1162
1163	  For information on utilities to make use of this driver see the
1164	  Toshiba Linux utilities web site at:
1165	  <http://www.buzzard.org.uk/toshiba/>.
1166
1167	  Say Y if you intend to run this kernel on a Toshiba portable.
1168	  Say N otherwise.
1169
1170config I8K
1171	tristate "Dell i8k legacy laptop support"
1172	select HWMON
1173	select SENSORS_DELL_SMM
1174	---help---
1175	  This option enables legacy /proc/i8k userspace interface in hwmon
1176	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1177	  temperature and allows controlling fan speeds of Dell laptops via
1178	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1179	  it reports also power and hotkey status. For fan speed control is
1180	  needed userspace package i8kutils.
1181
1182	  Say Y if you intend to run this kernel on old Dell laptops or want to
1183	  use userspace package i8kutils.
1184	  Say N otherwise.
1185
1186config X86_REBOOTFIXUPS
1187	bool "Enable X86 board specific fixups for reboot"
1188	depends on X86_32
1189	---help---
1190	  This enables chipset and/or board specific fixups to be done
1191	  in order to get reboot to work correctly. This is only needed on
1192	  some combinations of hardware and BIOS. The symptom, for which
1193	  this config is intended, is when reboot ends with a stalled/hung
1194	  system.
1195
1196	  Currently, the only fixup is for the Geode machines using
1197	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1198
1199	  Say Y if you want to enable the fixup. Currently, it's safe to
1200	  enable this option even if you don't need it.
1201	  Say N otherwise.
1202
1203config MICROCODE
1204	bool "CPU microcode loading support"
1205	default y
1206	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1207	select FW_LOADER
1208	---help---
1209	  If you say Y here, you will be able to update the microcode on
1210	  Intel and AMD processors. The Intel support is for the IA32 family,
1211	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1212	  AMD support is for families 0x10 and later. You will obviously need
1213	  the actual microcode binary data itself which is not shipped with
1214	  the Linux kernel.
1215
1216	  The preferred method to load microcode from a detached initrd is described
1217	  in Documentation/x86/early-microcode.txt. For that you need to enable
1218	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1219	  initrd for microcode blobs.
1220
1221	  In addition, you can build-in the microcode into the kernel. For that you
1222	  need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
1223	  to the CONFIG_EXTRA_FIRMWARE config option.
1224
1225config MICROCODE_INTEL
1226	bool "Intel microcode loading support"
1227	depends on MICROCODE
1228	default MICROCODE
1229	select FW_LOADER
1230	---help---
1231	  This options enables microcode patch loading support for Intel
1232	  processors.
1233
1234	  For the current Intel microcode data package go to
1235	  <https://downloadcenter.intel.com> and search for
1236	  'Linux Processor Microcode Data File'.
1237
1238config MICROCODE_AMD
1239	bool "AMD microcode loading support"
1240	depends on MICROCODE
1241	select FW_LOADER
1242	---help---
1243	  If you select this option, microcode patch loading support for AMD
1244	  processors will be enabled.
1245
1246config MICROCODE_OLD_INTERFACE
1247	def_bool y
1248	depends on MICROCODE
1249
1250config X86_MSR
1251	tristate "/dev/cpu/*/msr - Model-specific register support"
1252	---help---
1253	  This device gives privileged processes access to the x86
1254	  Model-Specific Registers (MSRs).  It is a character device with
1255	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1256	  MSR accesses are directed to a specific CPU on multi-processor
1257	  systems.
1258
1259config X86_CPUID
1260	tristate "/dev/cpu/*/cpuid - CPU information support"
1261	---help---
1262	  This device gives processes access to the x86 CPUID instruction to
1263	  be executed on a specific processor.  It is a character device
1264	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1265	  /dev/cpu/31/cpuid.
1266
1267choice
1268	prompt "High Memory Support"
1269	default HIGHMEM4G
1270	depends on X86_32
1271
1272config NOHIGHMEM
1273	bool "off"
1274	---help---
1275	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1276	  However, the address space of 32-bit x86 processors is only 4
1277	  Gigabytes large. That means that, if you have a large amount of
1278	  physical memory, not all of it can be "permanently mapped" by the
1279	  kernel. The physical memory that's not permanently mapped is called
1280	  "high memory".
1281
1282	  If you are compiling a kernel which will never run on a machine with
1283	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1284	  choice and suitable for most users). This will result in a "3GB/1GB"
1285	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1286	  space and the remaining part of the 4GB virtual memory space is used
1287	  by the kernel to permanently map as much physical memory as
1288	  possible.
1289
1290	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1291	  answer "4GB" here.
1292
1293	  If more than 4 Gigabytes is used then answer "64GB" here. This
1294	  selection turns Intel PAE (Physical Address Extension) mode on.
1295	  PAE implements 3-level paging on IA32 processors. PAE is fully
1296	  supported by Linux, PAE mode is implemented on all recent Intel
1297	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1298	  then the kernel will not boot on CPUs that don't support PAE!
1299
1300	  The actual amount of total physical memory will either be
1301	  auto detected or can be forced by using a kernel command line option
1302	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1303	  your boot loader (lilo or loadlin) about how to pass options to the
1304	  kernel at boot time.)
1305
1306	  If unsure, say "off".
1307
1308config HIGHMEM4G
1309	bool "4GB"
1310	---help---
1311	  Select this if you have a 32-bit processor and between 1 and 4
1312	  gigabytes of physical RAM.
1313
1314config HIGHMEM64G
1315	bool "64GB"
1316	depends on !M486
1317	select X86_PAE
1318	---help---
1319	  Select this if you have a 32-bit processor and more than 4
1320	  gigabytes of physical RAM.
1321
1322endchoice
1323
1324choice
1325	prompt "Memory split" if EXPERT
1326	default VMSPLIT_3G
1327	depends on X86_32
1328	---help---
1329	  Select the desired split between kernel and user memory.
1330
1331	  If the address range available to the kernel is less than the
1332	  physical memory installed, the remaining memory will be available
1333	  as "high memory". Accessing high memory is a little more costly
1334	  than low memory, as it needs to be mapped into the kernel first.
1335	  Note that increasing the kernel address space limits the range
1336	  available to user programs, making the address space there
1337	  tighter.  Selecting anything other than the default 3G/1G split
1338	  will also likely make your kernel incompatible with binary-only
1339	  kernel modules.
1340
1341	  If you are not absolutely sure what you are doing, leave this
1342	  option alone!
1343
1344	config VMSPLIT_3G
1345		bool "3G/1G user/kernel split"
1346	config VMSPLIT_3G_OPT
1347		depends on !X86_PAE
1348		bool "3G/1G user/kernel split (for full 1G low memory)"
1349	config VMSPLIT_2G
1350		bool "2G/2G user/kernel split"
1351	config VMSPLIT_2G_OPT
1352		depends on !X86_PAE
1353		bool "2G/2G user/kernel split (for full 2G low memory)"
1354	config VMSPLIT_1G
1355		bool "1G/3G user/kernel split"
1356endchoice
1357
1358config PAGE_OFFSET
1359	hex
1360	default 0xB0000000 if VMSPLIT_3G_OPT
1361	default 0x80000000 if VMSPLIT_2G
1362	default 0x78000000 if VMSPLIT_2G_OPT
1363	default 0x40000000 if VMSPLIT_1G
1364	default 0xC0000000
1365	depends on X86_32
1366
1367config HIGHMEM
1368	def_bool y
1369	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1370
1371config X86_PAE
1372	bool "PAE (Physical Address Extension) Support"
1373	depends on X86_32 && !HIGHMEM4G
1374	select SWIOTLB
1375	---help---
1376	  PAE is required for NX support, and furthermore enables
1377	  larger swapspace support for non-overcommit purposes. It
1378	  has the cost of more pagetable lookup overhead, and also
1379	  consumes more pagetable space per process.
1380
1381config ARCH_PHYS_ADDR_T_64BIT
1382	def_bool y
1383	depends on X86_64 || X86_PAE
1384
1385config ARCH_DMA_ADDR_T_64BIT
1386	def_bool y
1387	depends on X86_64 || HIGHMEM64G
1388
1389config X86_DIRECT_GBPAGES
1390	def_bool y
1391	depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1392	---help---
1393	  Certain kernel features effectively disable kernel
1394	  linear 1 GB mappings (even if the CPU otherwise
1395	  supports them), so don't confuse the user by printing
1396	  that we have them enabled.
1397
1398# Common NUMA Features
1399config NUMA
1400	bool "Numa Memory Allocation and Scheduler Support"
1401	depends on SMP
1402	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1403	default y if X86_BIGSMP
1404	---help---
1405	  Enable NUMA (Non Uniform Memory Access) support.
1406
1407	  The kernel will try to allocate memory used by a CPU on the
1408	  local memory controller of the CPU and add some more
1409	  NUMA awareness to the kernel.
1410
1411	  For 64-bit this is recommended if the system is Intel Core i7
1412	  (or later), AMD Opteron, or EM64T NUMA.
1413
1414	  For 32-bit this is only needed if you boot a 32-bit
1415	  kernel on a 64-bit NUMA platform.
1416
1417	  Otherwise, you should say N.
1418
1419config AMD_NUMA
1420	def_bool y
1421	prompt "Old style AMD Opteron NUMA detection"
1422	depends on X86_64 && NUMA && PCI
1423	---help---
1424	  Enable AMD NUMA node topology detection.  You should say Y here if
1425	  you have a multi processor AMD system. This uses an old method to
1426	  read the NUMA configuration directly from the builtin Northbridge
1427	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1428	  which also takes priority if both are compiled in.
1429
1430config X86_64_ACPI_NUMA
1431	def_bool y
1432	prompt "ACPI NUMA detection"
1433	depends on X86_64 && NUMA && ACPI && PCI
1434	select ACPI_NUMA
1435	---help---
1436	  Enable ACPI SRAT based node topology detection.
1437
1438# Some NUMA nodes have memory ranges that span
1439# other nodes.  Even though a pfn is valid and
1440# between a node's start and end pfns, it may not
1441# reside on that node.  See memmap_init_zone()
1442# for details.
1443config NODES_SPAN_OTHER_NODES
1444	def_bool y
1445	depends on X86_64_ACPI_NUMA
1446
1447config NUMA_EMU
1448	bool "NUMA emulation"
1449	depends on NUMA
1450	---help---
1451	  Enable NUMA emulation. A flat machine will be split
1452	  into virtual nodes when booted with "numa=fake=N", where N is the
1453	  number of nodes. This is only useful for debugging.
1454
1455config NODES_SHIFT
1456	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1457	range 1 10
1458	default "10" if MAXSMP
1459	default "6" if X86_64
1460	default "3"
1461	depends on NEED_MULTIPLE_NODES
1462	---help---
1463	  Specify the maximum number of NUMA Nodes available on the target
1464	  system.  Increases memory reserved to accommodate various tables.
1465
1466config ARCH_HAVE_MEMORY_PRESENT
1467	def_bool y
1468	depends on X86_32 && DISCONTIGMEM
1469
1470config NEED_NODE_MEMMAP_SIZE
1471	def_bool y
1472	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1473
1474config ARCH_FLATMEM_ENABLE
1475	def_bool y
1476	depends on X86_32 && !NUMA
1477
1478config ARCH_DISCONTIGMEM_ENABLE
1479	def_bool y
1480	depends on NUMA && X86_32
1481
1482config ARCH_DISCONTIGMEM_DEFAULT
1483	def_bool y
1484	depends on NUMA && X86_32
1485
1486config ARCH_SPARSEMEM_ENABLE
1487	def_bool y
1488	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1489	select SPARSEMEM_STATIC if X86_32
1490	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1491
1492config ARCH_SPARSEMEM_DEFAULT
1493	def_bool y
1494	depends on X86_64
1495
1496config ARCH_SELECT_MEMORY_MODEL
1497	def_bool y
1498	depends on ARCH_SPARSEMEM_ENABLE
1499
1500config ARCH_MEMORY_PROBE
1501	bool "Enable sysfs memory/probe interface"
1502	depends on X86_64 && MEMORY_HOTPLUG
1503	help
1504	  This option enables a sysfs memory/probe interface for testing.
1505	  See Documentation/memory-hotplug.txt for more information.
1506	  If you are unsure how to answer this question, answer N.
1507
1508config ARCH_PROC_KCORE_TEXT
1509	def_bool y
1510	depends on X86_64 && PROC_KCORE
1511
1512config ILLEGAL_POINTER_VALUE
1513       hex
1514       default 0 if X86_32
1515       default 0xdead000000000000 if X86_64
1516
1517source "mm/Kconfig"
1518
1519config X86_PMEM_LEGACY_DEVICE
1520	bool
1521
1522config X86_PMEM_LEGACY
1523	tristate "Support non-standard NVDIMMs and ADR protected memory"
1524	depends on PHYS_ADDR_T_64BIT
1525	depends on BLK_DEV
1526	select X86_PMEM_LEGACY_DEVICE
1527	select LIBNVDIMM
1528	help
1529	  Treat memory marked using the non-standard e820 type of 12 as used
1530	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1531	  The kernel will offer these regions to the 'pmem' driver so
1532	  they can be used for persistent storage.
1533
1534	  Say Y if unsure.
1535
1536config HIGHPTE
1537	bool "Allocate 3rd-level pagetables from highmem"
1538	depends on HIGHMEM
1539	---help---
1540	  The VM uses one page table entry for each page of physical memory.
1541	  For systems with a lot of RAM, this can be wasteful of precious
1542	  low memory.  Setting this option will put user-space page table
1543	  entries in high memory.
1544
1545config X86_CHECK_BIOS_CORRUPTION
1546	bool "Check for low memory corruption"
1547	---help---
1548	  Periodically check for memory corruption in low memory, which
1549	  is suspected to be caused by BIOS.  Even when enabled in the
1550	  configuration, it is disabled at runtime.  Enable it by
1551	  setting "memory_corruption_check=1" on the kernel command
1552	  line.  By default it scans the low 64k of memory every 60
1553	  seconds; see the memory_corruption_check_size and
1554	  memory_corruption_check_period parameters in
1555	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
1556
1557	  When enabled with the default parameters, this option has
1558	  almost no overhead, as it reserves a relatively small amount
1559	  of memory and scans it infrequently.  It both detects corruption
1560	  and prevents it from affecting the running system.
1561
1562	  It is, however, intended as a diagnostic tool; if repeatable
1563	  BIOS-originated corruption always affects the same memory,
1564	  you can use memmap= to prevent the kernel from using that
1565	  memory.
1566
1567config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1568	bool "Set the default setting of memory_corruption_check"
1569	depends on X86_CHECK_BIOS_CORRUPTION
1570	default y
1571	---help---
1572	  Set whether the default state of memory_corruption_check is
1573	  on or off.
1574
1575config X86_RESERVE_LOW
1576	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1577	default 64
1578	range 4 640
1579	---help---
1580	  Specify the amount of low memory to reserve for the BIOS.
1581
1582	  The first page contains BIOS data structures that the kernel
1583	  must not use, so that page must always be reserved.
1584
1585	  By default we reserve the first 64K of physical RAM, as a
1586	  number of BIOSes are known to corrupt that memory range
1587	  during events such as suspend/resume or monitor cable
1588	  insertion, so it must not be used by the kernel.
1589
1590	  You can set this to 4 if you are absolutely sure that you
1591	  trust the BIOS to get all its memory reservations and usages
1592	  right.  If you know your BIOS have problems beyond the
1593	  default 64K area, you can set this to 640 to avoid using the
1594	  entire low memory range.
1595
1596	  If you have doubts about the BIOS (e.g. suspend/resume does
1597	  not work or there's kernel crashes after certain hardware
1598	  hotplug events) then you might want to enable
1599	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1600	  typical corruption patterns.
1601
1602	  Leave this to the default value of 64 if you are unsure.
1603
1604config MATH_EMULATION
1605	bool
1606	depends on MODIFY_LDT_SYSCALL
1607	prompt "Math emulation" if X86_32
1608	---help---
1609	  Linux can emulate a math coprocessor (used for floating point
1610	  operations) if you don't have one. 486DX and Pentium processors have
1611	  a math coprocessor built in, 486SX and 386 do not, unless you added
1612	  a 487DX or 387, respectively. (The messages during boot time can
1613	  give you some hints here ["man dmesg"].) Everyone needs either a
1614	  coprocessor or this emulation.
1615
1616	  If you don't have a math coprocessor, you need to say Y here; if you
1617	  say Y here even though you have a coprocessor, the coprocessor will
1618	  be used nevertheless. (This behavior can be changed with the kernel
1619	  command line option "no387", which comes handy if your coprocessor
1620	  is broken. Try "man bootparam" or see the documentation of your boot
1621	  loader (lilo or loadlin) about how to pass options to the kernel at
1622	  boot time.) This means that it is a good idea to say Y here if you
1623	  intend to use this kernel on different machines.
1624
1625	  More information about the internals of the Linux math coprocessor
1626	  emulation can be found in <file:arch/x86/math-emu/README>.
1627
1628	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1629	  kernel, it won't hurt.
1630
1631config MTRR
1632	def_bool y
1633	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1634	---help---
1635	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1636	  the Memory Type Range Registers (MTRRs) may be used to control
1637	  processor access to memory ranges. This is most useful if you have
1638	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1639	  allows bus write transfers to be combined into a larger transfer
1640	  before bursting over the PCI/AGP bus. This can increase performance
1641	  of image write operations 2.5 times or more. Saying Y here creates a
1642	  /proc/mtrr file which may be used to manipulate your processor's
1643	  MTRRs. Typically the X server should use this.
1644
1645	  This code has a reasonably generic interface so that similar
1646	  control registers on other processors can be easily supported
1647	  as well:
1648
1649	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1650	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1651	  these, the ARRs are used to emulate the MTRRs.
1652	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1653	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1654	  write-combining. All of these processors are supported by this code
1655	  and it makes sense to say Y here if you have one of them.
1656
1657	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1658	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1659	  can lead to all sorts of problems, so it's good to say Y here.
1660
1661	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1662	  just add about 9 KB to your kernel.
1663
1664	  See <file:Documentation/x86/mtrr.txt> for more information.
1665
1666config MTRR_SANITIZER
1667	def_bool y
1668	prompt "MTRR cleanup support"
1669	depends on MTRR
1670	---help---
1671	  Convert MTRR layout from continuous to discrete, so X drivers can
1672	  add writeback entries.
1673
1674	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1675	  The largest mtrr entry size for a continuous block can be set with
1676	  mtrr_chunk_size.
1677
1678	  If unsure, say Y.
1679
1680config MTRR_SANITIZER_ENABLE_DEFAULT
1681	int "MTRR cleanup enable value (0-1)"
1682	range 0 1
1683	default "0"
1684	depends on MTRR_SANITIZER
1685	---help---
1686	  Enable mtrr cleanup default value
1687
1688config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1689	int "MTRR cleanup spare reg num (0-7)"
1690	range 0 7
1691	default "1"
1692	depends on MTRR_SANITIZER
1693	---help---
1694	  mtrr cleanup spare entries default, it can be changed via
1695	  mtrr_spare_reg_nr=N on the kernel command line.
1696
1697config X86_PAT
1698	def_bool y
1699	prompt "x86 PAT support" if EXPERT
1700	depends on MTRR
1701	---help---
1702	  Use PAT attributes to setup page level cache control.
1703
1704	  PATs are the modern equivalents of MTRRs and are much more
1705	  flexible than MTRRs.
1706
1707	  Say N here if you see bootup problems (boot crash, boot hang,
1708	  spontaneous reboots) or a non-working video driver.
1709
1710	  If unsure, say Y.
1711
1712config ARCH_USES_PG_UNCACHED
1713	def_bool y
1714	depends on X86_PAT
1715
1716config ARCH_RANDOM
1717	def_bool y
1718	prompt "x86 architectural random number generator" if EXPERT
1719	---help---
1720	  Enable the x86 architectural RDRAND instruction
1721	  (Intel Bull Mountain technology) to generate random numbers.
1722	  If supported, this is a high bandwidth, cryptographically
1723	  secure hardware random number generator.
1724
1725config X86_SMAP
1726	def_bool y
1727	prompt "Supervisor Mode Access Prevention" if EXPERT
1728	---help---
1729	  Supervisor Mode Access Prevention (SMAP) is a security
1730	  feature in newer Intel processors.  There is a small
1731	  performance cost if this enabled and turned on; there is
1732	  also a small increase in the kernel size if this is enabled.
1733
1734	  If unsure, say Y.
1735
1736config X86_INTEL_MPX
1737	prompt "Intel MPX (Memory Protection Extensions)"
1738	def_bool n
1739	depends on CPU_SUP_INTEL
1740	---help---
1741	  MPX provides hardware features that can be used in
1742	  conjunction with compiler-instrumented code to check
1743	  memory references.  It is designed to detect buffer
1744	  overflow or underflow bugs.
1745
1746	  This option enables running applications which are
1747	  instrumented or otherwise use MPX.  It does not use MPX
1748	  itself inside the kernel or to protect the kernel
1749	  against bad memory references.
1750
1751	  Enabling this option will make the kernel larger:
1752	  ~8k of kernel text and 36 bytes of data on a 64-bit
1753	  defconfig.  It adds a long to the 'mm_struct' which
1754	  will increase the kernel memory overhead of each
1755	  process and adds some branches to paths used during
1756	  exec() and munmap().
1757
1758	  For details, see Documentation/x86/intel_mpx.txt
1759
1760	  If unsure, say N.
1761
1762config X86_INTEL_MEMORY_PROTECTION_KEYS
1763	prompt "Intel Memory Protection Keys"
1764	def_bool y
1765	# Note: only available in 64-bit mode
1766	depends on CPU_SUP_INTEL && X86_64
1767	select ARCH_USES_HIGH_VMA_FLAGS
1768	select ARCH_HAS_PKEYS
1769	---help---
1770	  Memory Protection Keys provides a mechanism for enforcing
1771	  page-based protections, but without requiring modification of the
1772	  page tables when an application changes protection domains.
1773
1774	  For details, see Documentation/x86/protection-keys.txt
1775
1776	  If unsure, say y.
1777
1778config EFI
1779	bool "EFI runtime service support"
1780	depends on ACPI
1781	select UCS2_STRING
1782	select EFI_RUNTIME_WRAPPERS
1783	---help---
1784	  This enables the kernel to use EFI runtime services that are
1785	  available (such as the EFI variable services).
1786
1787	  This option is only useful on systems that have EFI firmware.
1788	  In addition, you should use the latest ELILO loader available
1789	  at <http://elilo.sourceforge.net> in order to take advantage
1790	  of EFI runtime services. However, even with this option, the
1791	  resultant kernel should continue to boot on existing non-EFI
1792	  platforms.
1793
1794config EFI_STUB
1795       bool "EFI stub support"
1796       depends on EFI && !X86_USE_3DNOW
1797       select RELOCATABLE
1798       ---help---
1799          This kernel feature allows a bzImage to be loaded directly
1800	  by EFI firmware without the use of a bootloader.
1801
1802	  See Documentation/efi-stub.txt for more information.
1803
1804config EFI_MIXED
1805	bool "EFI mixed-mode support"
1806	depends on EFI_STUB && X86_64
1807	---help---
1808	   Enabling this feature allows a 64-bit kernel to be booted
1809	   on a 32-bit firmware, provided that your CPU supports 64-bit
1810	   mode.
1811
1812	   Note that it is not possible to boot a mixed-mode enabled
1813	   kernel via the EFI boot stub - a bootloader that supports
1814	   the EFI handover protocol must be used.
1815
1816	   If unsure, say N.
1817
1818config SECCOMP
1819	def_bool y
1820	prompt "Enable seccomp to safely compute untrusted bytecode"
1821	---help---
1822	  This kernel feature is useful for number crunching applications
1823	  that may need to compute untrusted bytecode during their
1824	  execution. By using pipes or other transports made available to
1825	  the process as file descriptors supporting the read/write
1826	  syscalls, it's possible to isolate those applications in
1827	  their own address space using seccomp. Once seccomp is
1828	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1829	  and the task is only allowed to execute a few safe syscalls
1830	  defined by each seccomp mode.
1831
1832	  If unsure, say Y. Only embedded should say N here.
1833
1834source kernel/Kconfig.hz
1835
1836config KEXEC
1837	bool "kexec system call"
1838	select KEXEC_CORE
1839	---help---
1840	  kexec is a system call that implements the ability to shutdown your
1841	  current kernel, and to start another kernel.  It is like a reboot
1842	  but it is independent of the system firmware.   And like a reboot
1843	  you can start any kernel with it, not just Linux.
1844
1845	  The name comes from the similarity to the exec system call.
1846
1847	  It is an ongoing process to be certain the hardware in a machine
1848	  is properly shutdown, so do not be surprised if this code does not
1849	  initially work for you.  As of this writing the exact hardware
1850	  interface is strongly in flux, so no good recommendation can be
1851	  made.
1852
1853config KEXEC_FILE
1854	bool "kexec file based system call"
1855	select KEXEC_CORE
1856	select BUILD_BIN2C
1857	depends on X86_64
1858	depends on CRYPTO=y
1859	depends on CRYPTO_SHA256=y
1860	---help---
1861	  This is new version of kexec system call. This system call is
1862	  file based and takes file descriptors as system call argument
1863	  for kernel and initramfs as opposed to list of segments as
1864	  accepted by previous system call.
1865
1866config KEXEC_VERIFY_SIG
1867	bool "Verify kernel signature during kexec_file_load() syscall"
1868	depends on KEXEC_FILE
1869	---help---
1870	  This option makes kernel signature verification mandatory for
1871	  the kexec_file_load() syscall.
1872
1873	  In addition to that option, you need to enable signature
1874	  verification for the corresponding kernel image type being
1875	  loaded in order for this to work.
1876
1877config KEXEC_BZIMAGE_VERIFY_SIG
1878	bool "Enable bzImage signature verification support"
1879	depends on KEXEC_VERIFY_SIG
1880	depends on SIGNED_PE_FILE_VERIFICATION
1881	select SYSTEM_TRUSTED_KEYRING
1882	---help---
1883	  Enable bzImage signature verification support.
1884
1885config CRASH_DUMP
1886	bool "kernel crash dumps"
1887	depends on X86_64 || (X86_32 && HIGHMEM)
1888	---help---
1889	  Generate crash dump after being started by kexec.
1890	  This should be normally only set in special crash dump kernels
1891	  which are loaded in the main kernel with kexec-tools into
1892	  a specially reserved region and then later executed after
1893	  a crash by kdump/kexec. The crash dump kernel must be compiled
1894	  to a memory address not used by the main kernel or BIOS using
1895	  PHYSICAL_START, or it must be built as a relocatable image
1896	  (CONFIG_RELOCATABLE=y).
1897	  For more details see Documentation/kdump/kdump.txt
1898
1899config KEXEC_JUMP
1900	bool "kexec jump"
1901	depends on KEXEC && HIBERNATION
1902	---help---
1903	  Jump between original kernel and kexeced kernel and invoke
1904	  code in physical address mode via KEXEC
1905
1906config PHYSICAL_START
1907	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1908	default "0x1000000"
1909	---help---
1910	  This gives the physical address where the kernel is loaded.
1911
1912	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1913	  bzImage will decompress itself to above physical address and
1914	  run from there. Otherwise, bzImage will run from the address where
1915	  it has been loaded by the boot loader and will ignore above physical
1916	  address.
1917
1918	  In normal kdump cases one does not have to set/change this option
1919	  as now bzImage can be compiled as a completely relocatable image
1920	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1921	  address. This option is mainly useful for the folks who don't want
1922	  to use a bzImage for capturing the crash dump and want to use a
1923	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1924	  to be specifically compiled to run from a specific memory area
1925	  (normally a reserved region) and this option comes handy.
1926
1927	  So if you are using bzImage for capturing the crash dump,
1928	  leave the value here unchanged to 0x1000000 and set
1929	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1930	  for capturing the crash dump change this value to start of
1931	  the reserved region.  In other words, it can be set based on
1932	  the "X" value as specified in the "crashkernel=YM@XM"
1933	  command line boot parameter passed to the panic-ed
1934	  kernel. Please take a look at Documentation/kdump/kdump.txt
1935	  for more details about crash dumps.
1936
1937	  Usage of bzImage for capturing the crash dump is recommended as
1938	  one does not have to build two kernels. Same kernel can be used
1939	  as production kernel and capture kernel. Above option should have
1940	  gone away after relocatable bzImage support is introduced. But it
1941	  is present because there are users out there who continue to use
1942	  vmlinux for dump capture. This option should go away down the
1943	  line.
1944
1945	  Don't change this unless you know what you are doing.
1946
1947config RELOCATABLE
1948	bool "Build a relocatable kernel"
1949	default y
1950	---help---
1951	  This builds a kernel image that retains relocation information
1952	  so it can be loaded someplace besides the default 1MB.
1953	  The relocations tend to make the kernel binary about 10% larger,
1954	  but are discarded at runtime.
1955
1956	  One use is for the kexec on panic case where the recovery kernel
1957	  must live at a different physical address than the primary
1958	  kernel.
1959
1960	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1961	  it has been loaded at and the compile time physical address
1962	  (CONFIG_PHYSICAL_START) is used as the minimum location.
1963
1964config RANDOMIZE_BASE
1965	bool "Randomize the address of the kernel image (KASLR)"
1966	depends on RELOCATABLE
1967	default n
1968	---help---
1969	  In support of Kernel Address Space Layout Randomization (KASLR),
1970	  this randomizes the physical address at which the kernel image
1971	  is decompressed and the virtual address where the kernel
1972	  image is mapped, as a security feature that deters exploit
1973	  attempts relying on knowledge of the location of kernel
1974	  code internals.
1975
1976	  On 64-bit, the kernel physical and virtual addresses are
1977	  randomized separately. The physical address will be anywhere
1978	  between 16MB and the top of physical memory (up to 64TB). The
1979	  virtual address will be randomized from 16MB up to 1GB (9 bits
1980	  of entropy). Note that this also reduces the memory space
1981	  available to kernel modules from 1.5GB to 1GB.
1982
1983	  On 32-bit, the kernel physical and virtual addresses are
1984	  randomized together. They will be randomized from 16MB up to
1985	  512MB (8 bits of entropy).
1986
1987	  Entropy is generated using the RDRAND instruction if it is
1988	  supported. If RDTSC is supported, its value is mixed into
1989	  the entropy pool as well. If neither RDRAND nor RDTSC are
1990	  supported, then entropy is read from the i8254 timer. The
1991	  usable entropy is limited by the kernel being built using
1992	  2GB addressing, and that PHYSICAL_ALIGN must be at a
1993	  minimum of 2MB. As a result, only 10 bits of entropy are
1994	  theoretically possible, but the implementations are further
1995	  limited due to memory layouts.
1996
1997	  If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot
1998	  time. To enable it, boot with "kaslr" on the kernel command
1999	  line (which will also disable hibernation).
2000
2001	  If unsure, say N.
2002
2003# Relocation on x86 needs some additional build support
2004config X86_NEED_RELOCS
2005	def_bool y
2006	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2007
2008config PHYSICAL_ALIGN
2009	hex "Alignment value to which kernel should be aligned"
2010	default "0x200000"
2011	range 0x2000 0x1000000 if X86_32
2012	range 0x200000 0x1000000 if X86_64
2013	---help---
2014	  This value puts the alignment restrictions on physical address
2015	  where kernel is loaded and run from. Kernel is compiled for an
2016	  address which meets above alignment restriction.
2017
2018	  If bootloader loads the kernel at a non-aligned address and
2019	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2020	  address aligned to above value and run from there.
2021
2022	  If bootloader loads the kernel at a non-aligned address and
2023	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2024	  load address and decompress itself to the address it has been
2025	  compiled for and run from there. The address for which kernel is
2026	  compiled already meets above alignment restrictions. Hence the
2027	  end result is that kernel runs from a physical address meeting
2028	  above alignment restrictions.
2029
2030	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2031	  this value must be a multiple of 0x200000.
2032
2033	  Don't change this unless you know what you are doing.
2034
2035config RANDOMIZE_MEMORY
2036	bool "Randomize the kernel memory sections"
2037	depends on X86_64
2038	depends on RANDOMIZE_BASE
2039	default RANDOMIZE_BASE
2040	---help---
2041	   Randomizes the base virtual address of kernel memory sections
2042	   (physical memory mapping, vmalloc & vmemmap). This security feature
2043	   makes exploits relying on predictable memory locations less reliable.
2044
2045	   The order of allocations remains unchanged. Entropy is generated in
2046	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
2047	   configuration have in average 30,000 different possible virtual
2048	   addresses for each memory section.
2049
2050	   If unsure, say N.
2051
2052config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2053	hex "Physical memory mapping padding" if EXPERT
2054	depends on RANDOMIZE_MEMORY
2055	default "0xa" if MEMORY_HOTPLUG
2056	default "0x0"
2057	range 0x1 0x40 if MEMORY_HOTPLUG
2058	range 0x0 0x40
2059	---help---
2060	   Define the padding in terabytes added to the existing physical
2061	   memory size during kernel memory randomization. It is useful
2062	   for memory hotplug support but reduces the entropy available for
2063	   address randomization.
2064
2065	   If unsure, leave at the default value.
2066
2067config HOTPLUG_CPU
2068	bool "Support for hot-pluggable CPUs"
2069	depends on SMP
2070	---help---
2071	  Say Y here to allow turning CPUs off and on. CPUs can be
2072	  controlled through /sys/devices/system/cpu.
2073	  ( Note: power management support will enable this option
2074	    automatically on SMP systems. )
2075	  Say N if you want to disable CPU hotplug.
2076
2077config BOOTPARAM_HOTPLUG_CPU0
2078	bool "Set default setting of cpu0_hotpluggable"
2079	default n
2080	depends on HOTPLUG_CPU
2081	---help---
2082	  Set whether default state of cpu0_hotpluggable is on or off.
2083
2084	  Say Y here to enable CPU0 hotplug by default. If this switch
2085	  is turned on, there is no need to give cpu0_hotplug kernel
2086	  parameter and the CPU0 hotplug feature is enabled by default.
2087
2088	  Please note: there are two known CPU0 dependencies if you want
2089	  to enable the CPU0 hotplug feature either by this switch or by
2090	  cpu0_hotplug kernel parameter.
2091
2092	  First, resume from hibernate or suspend always starts from CPU0.
2093	  So hibernate and suspend are prevented if CPU0 is offline.
2094
2095	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2096	  offline if any interrupt can not migrate out of CPU0. There may
2097	  be other CPU0 dependencies.
2098
2099	  Please make sure the dependencies are under your control before
2100	  you enable this feature.
2101
2102	  Say N if you don't want to enable CPU0 hotplug feature by default.
2103	  You still can enable the CPU0 hotplug feature at boot by kernel
2104	  parameter cpu0_hotplug.
2105
2106config DEBUG_HOTPLUG_CPU0
2107	def_bool n
2108	prompt "Debug CPU0 hotplug"
2109	depends on HOTPLUG_CPU
2110	---help---
2111	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2112	  soon as possible and boots up userspace with CPU0 offlined. User
2113	  can online CPU0 back after boot time.
2114
2115	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2116	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2117	  compilation or giving cpu0_hotplug kernel parameter at boot.
2118
2119	  If unsure, say N.
2120
2121config COMPAT_VDSO
2122	def_bool n
2123	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2124	depends on COMPAT_32
2125	---help---
2126	  Certain buggy versions of glibc will crash if they are
2127	  presented with a 32-bit vDSO that is not mapped at the address
2128	  indicated in its segment table.
2129
2130	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2131	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2132	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2133	  the only released version with the bug, but OpenSUSE 9
2134	  contains a buggy "glibc 2.3.2".
2135
2136	  The symptom of the bug is that everything crashes on startup, saying:
2137	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2138
2139	  Saying Y here changes the default value of the vdso32 boot
2140	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2141	  This works around the glibc bug but hurts performance.
2142
2143	  If unsure, say N: if you are compiling your own kernel, you
2144	  are unlikely to be using a buggy version of glibc.
2145
2146choice
2147	prompt "vsyscall table for legacy applications"
2148	depends on X86_64
2149	default LEGACY_VSYSCALL_EMULATE
2150	help
2151	  Legacy user code that does not know how to find the vDSO expects
2152	  to be able to issue three syscalls by calling fixed addresses in
2153	  kernel space. Since this location is not randomized with ASLR,
2154	  it can be used to assist security vulnerability exploitation.
2155
2156	  This setting can be changed at boot time via the kernel command
2157	  line parameter vsyscall=[native|emulate|none].
2158
2159	  On a system with recent enough glibc (2.14 or newer) and no
2160	  static binaries, you can say None without a performance penalty
2161	  to improve security.
2162
2163	  If unsure, select "Emulate".
2164
2165	config LEGACY_VSYSCALL_NATIVE
2166		bool "Native"
2167		help
2168		  Actual executable code is located in the fixed vsyscall
2169		  address mapping, implementing time() efficiently. Since
2170		  this makes the mapping executable, it can be used during
2171		  security vulnerability exploitation (traditionally as
2172		  ROP gadgets). This configuration is not recommended.
2173
2174	config LEGACY_VSYSCALL_EMULATE
2175		bool "Emulate"
2176		help
2177		  The kernel traps and emulates calls into the fixed
2178		  vsyscall address mapping. This makes the mapping
2179		  non-executable, but it still contains known contents,
2180		  which could be used in certain rare security vulnerability
2181		  exploits. This configuration is recommended when userspace
2182		  still uses the vsyscall area.
2183
2184	config LEGACY_VSYSCALL_NONE
2185		bool "None"
2186		help
2187		  There will be no vsyscall mapping at all. This will
2188		  eliminate any risk of ASLR bypass due to the vsyscall
2189		  fixed address mapping. Attempts to use the vsyscalls
2190		  will be reported to dmesg, so that either old or
2191		  malicious userspace programs can be identified.
2192
2193endchoice
2194
2195config CMDLINE_BOOL
2196	bool "Built-in kernel command line"
2197	---help---
2198	  Allow for specifying boot arguments to the kernel at
2199	  build time.  On some systems (e.g. embedded ones), it is
2200	  necessary or convenient to provide some or all of the
2201	  kernel boot arguments with the kernel itself (that is,
2202	  to not rely on the boot loader to provide them.)
2203
2204	  To compile command line arguments into the kernel,
2205	  set this option to 'Y', then fill in the
2206	  boot arguments in CONFIG_CMDLINE.
2207
2208	  Systems with fully functional boot loaders (i.e. non-embedded)
2209	  should leave this option set to 'N'.
2210
2211config CMDLINE
2212	string "Built-in kernel command string"
2213	depends on CMDLINE_BOOL
2214	default ""
2215	---help---
2216	  Enter arguments here that should be compiled into the kernel
2217	  image and used at boot time.  If the boot loader provides a
2218	  command line at boot time, it is appended to this string to
2219	  form the full kernel command line, when the system boots.
2220
2221	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2222	  change this behavior.
2223
2224	  In most cases, the command line (whether built-in or provided
2225	  by the boot loader) should specify the device for the root
2226	  file system.
2227
2228config CMDLINE_OVERRIDE
2229	bool "Built-in command line overrides boot loader arguments"
2230	depends on CMDLINE_BOOL
2231	---help---
2232	  Set this option to 'Y' to have the kernel ignore the boot loader
2233	  command line, and use ONLY the built-in command line.
2234
2235	  This is used to work around broken boot loaders.  This should
2236	  be set to 'N' under normal conditions.
2237
2238config MODIFY_LDT_SYSCALL
2239	bool "Enable the LDT (local descriptor table)" if EXPERT
2240	default y
2241	---help---
2242	  Linux can allow user programs to install a per-process x86
2243	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2244	  call.  This is required to run 16-bit or segmented code such as
2245	  DOSEMU or some Wine programs.  It is also used by some very old
2246	  threading libraries.
2247
2248	  Enabling this feature adds a small amount of overhead to
2249	  context switches and increases the low-level kernel attack
2250	  surface.  Disabling it removes the modify_ldt(2) system call.
2251
2252	  Saying 'N' here may make sense for embedded or server kernels.
2253
2254source "kernel/livepatch/Kconfig"
2255
2256endmenu
2257
2258config ARCH_ENABLE_MEMORY_HOTPLUG
2259	def_bool y
2260	depends on X86_64 || (X86_32 && HIGHMEM)
2261
2262config ARCH_ENABLE_MEMORY_HOTREMOVE
2263	def_bool y
2264	depends on MEMORY_HOTPLUG
2265
2266config USE_PERCPU_NUMA_NODE_ID
2267	def_bool y
2268	depends on NUMA
2269
2270config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2271	def_bool y
2272	depends on X86_64 || X86_PAE
2273
2274config ARCH_ENABLE_HUGEPAGE_MIGRATION
2275	def_bool y
2276	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2277
2278menu "Power management and ACPI options"
2279
2280config ARCH_HIBERNATION_HEADER
2281	def_bool y
2282	depends on X86_64 && HIBERNATION
2283
2284source "kernel/power/Kconfig"
2285
2286source "drivers/acpi/Kconfig"
2287
2288source "drivers/sfi/Kconfig"
2289
2290config X86_APM_BOOT
2291	def_bool y
2292	depends on APM
2293
2294menuconfig APM
2295	tristate "APM (Advanced Power Management) BIOS support"
2296	depends on X86_32 && PM_SLEEP
2297	---help---
2298	  APM is a BIOS specification for saving power using several different
2299	  techniques. This is mostly useful for battery powered laptops with
2300	  APM compliant BIOSes. If you say Y here, the system time will be
2301	  reset after a RESUME operation, the /proc/apm device will provide
2302	  battery status information, and user-space programs will receive
2303	  notification of APM "events" (e.g. battery status change).
2304
2305	  If you select "Y" here, you can disable actual use of the APM
2306	  BIOS by passing the "apm=off" option to the kernel at boot time.
2307
2308	  Note that the APM support is almost completely disabled for
2309	  machines with more than one CPU.
2310
2311	  In order to use APM, you will need supporting software. For location
2312	  and more information, read <file:Documentation/power/apm-acpi.txt>
2313	  and the Battery Powered Linux mini-HOWTO, available from
2314	  <http://www.tldp.org/docs.html#howto>.
2315
2316	  This driver does not spin down disk drives (see the hdparm(8)
2317	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2318	  VESA-compliant "green" monitors.
2319
2320	  This driver does not support the TI 4000M TravelMate and the ACER
2321	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2322	  desktop machines also don't have compliant BIOSes, and this driver
2323	  may cause those machines to panic during the boot phase.
2324
2325	  Generally, if you don't have a battery in your machine, there isn't
2326	  much point in using this driver and you should say N. If you get
2327	  random kernel OOPSes or reboots that don't seem to be related to
2328	  anything, try disabling/enabling this option (or disabling/enabling
2329	  APM in your BIOS).
2330
2331	  Some other things you should try when experiencing seemingly random,
2332	  "weird" problems:
2333
2334	  1) make sure that you have enough swap space and that it is
2335	  enabled.
2336	  2) pass the "no-hlt" option to the kernel
2337	  3) switch on floating point emulation in the kernel and pass
2338	  the "no387" option to the kernel
2339	  4) pass the "floppy=nodma" option to the kernel
2340	  5) pass the "mem=4M" option to the kernel (thereby disabling
2341	  all but the first 4 MB of RAM)
2342	  6) make sure that the CPU is not over clocked.
2343	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2344	  8) disable the cache from your BIOS settings
2345	  9) install a fan for the video card or exchange video RAM
2346	  10) install a better fan for the CPU
2347	  11) exchange RAM chips
2348	  12) exchange the motherboard.
2349
2350	  To compile this driver as a module, choose M here: the
2351	  module will be called apm.
2352
2353if APM
2354
2355config APM_IGNORE_USER_SUSPEND
2356	bool "Ignore USER SUSPEND"
2357	---help---
2358	  This option will ignore USER SUSPEND requests. On machines with a
2359	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2360	  series notebooks, it is necessary to say Y because of a BIOS bug.
2361
2362config APM_DO_ENABLE
2363	bool "Enable PM at boot time"
2364	---help---
2365	  Enable APM features at boot time. From page 36 of the APM BIOS
2366	  specification: "When disabled, the APM BIOS does not automatically
2367	  power manage devices, enter the Standby State, enter the Suspend
2368	  State, or take power saving steps in response to CPU Idle calls."
2369	  This driver will make CPU Idle calls when Linux is idle (unless this
2370	  feature is turned off -- see "Do CPU IDLE calls", below). This
2371	  should always save battery power, but more complicated APM features
2372	  will be dependent on your BIOS implementation. You may need to turn
2373	  this option off if your computer hangs at boot time when using APM
2374	  support, or if it beeps continuously instead of suspending. Turn
2375	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2376	  T400CDT. This is off by default since most machines do fine without
2377	  this feature.
2378
2379config APM_CPU_IDLE
2380	depends on CPU_IDLE
2381	bool "Make CPU Idle calls when idle"
2382	---help---
2383	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2384	  On some machines, this can activate improved power savings, such as
2385	  a slowed CPU clock rate, when the machine is idle. These idle calls
2386	  are made after the idle loop has run for some length of time (e.g.,
2387	  333 mS). On some machines, this will cause a hang at boot time or
2388	  whenever the CPU becomes idle. (On machines with more than one CPU,
2389	  this option does nothing.)
2390
2391config APM_DISPLAY_BLANK
2392	bool "Enable console blanking using APM"
2393	---help---
2394	  Enable console blanking using the APM. Some laptops can use this to
2395	  turn off the LCD backlight when the screen blanker of the Linux
2396	  virtual console blanks the screen. Note that this is only used by
2397	  the virtual console screen blanker, and won't turn off the backlight
2398	  when using the X Window system. This also doesn't have anything to
2399	  do with your VESA-compliant power-saving monitor. Further, this
2400	  option doesn't work for all laptops -- it might not turn off your
2401	  backlight at all, or it might print a lot of errors to the console,
2402	  especially if you are using gpm.
2403
2404config APM_ALLOW_INTS
2405	bool "Allow interrupts during APM BIOS calls"
2406	---help---
2407	  Normally we disable external interrupts while we are making calls to
2408	  the APM BIOS as a measure to lessen the effects of a badly behaving
2409	  BIOS implementation.  The BIOS should reenable interrupts if it
2410	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2411	  many of the newer IBM Thinkpads.  If you experience hangs when you
2412	  suspend, try setting this to Y.  Otherwise, say N.
2413
2414endif # APM
2415
2416source "drivers/cpufreq/Kconfig"
2417
2418source "drivers/cpuidle/Kconfig"
2419
2420source "drivers/idle/Kconfig"
2421
2422endmenu
2423
2424
2425menu "Bus options (PCI etc.)"
2426
2427config PCI
2428	bool "PCI support"
2429	default y
2430	---help---
2431	  Find out whether you have a PCI motherboard. PCI is the name of a
2432	  bus system, i.e. the way the CPU talks to the other stuff inside
2433	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2434	  VESA. If you have PCI, say Y, otherwise N.
2435
2436choice
2437	prompt "PCI access mode"
2438	depends on X86_32 && PCI
2439	default PCI_GOANY
2440	---help---
2441	  On PCI systems, the BIOS can be used to detect the PCI devices and
2442	  determine their configuration. However, some old PCI motherboards
2443	  have BIOS bugs and may crash if this is done. Also, some embedded
2444	  PCI-based systems don't have any BIOS at all. Linux can also try to
2445	  detect the PCI hardware directly without using the BIOS.
2446
2447	  With this option, you can specify how Linux should detect the
2448	  PCI devices. If you choose "BIOS", the BIOS will be used,
2449	  if you choose "Direct", the BIOS won't be used, and if you
2450	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2451	  If you choose "Any", the kernel will try MMCONFIG, then the
2452	  direct access method and falls back to the BIOS if that doesn't
2453	  work. If unsure, go with the default, which is "Any".
2454
2455config PCI_GOBIOS
2456	bool "BIOS"
2457
2458config PCI_GOMMCONFIG
2459	bool "MMConfig"
2460
2461config PCI_GODIRECT
2462	bool "Direct"
2463
2464config PCI_GOOLPC
2465	bool "OLPC XO-1"
2466	depends on OLPC
2467
2468config PCI_GOANY
2469	bool "Any"
2470
2471endchoice
2472
2473config PCI_BIOS
2474	def_bool y
2475	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2476
2477# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2478config PCI_DIRECT
2479	def_bool y
2480	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2481
2482config PCI_MMCONFIG
2483	def_bool y
2484	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2485
2486config PCI_OLPC
2487	def_bool y
2488	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2489
2490config PCI_XEN
2491	def_bool y
2492	depends on PCI && XEN
2493	select SWIOTLB_XEN
2494
2495config PCI_DOMAINS
2496	def_bool y
2497	depends on PCI
2498
2499config PCI_MMCONFIG
2500	bool "Support mmconfig PCI config space access"
2501	depends on X86_64 && PCI && ACPI
2502
2503config PCI_CNB20LE_QUIRK
2504	bool "Read CNB20LE Host Bridge Windows" if EXPERT
2505	depends on PCI
2506	help
2507	  Read the PCI windows out of the CNB20LE host bridge. This allows
2508	  PCI hotplug to work on systems with the CNB20LE chipset which do
2509	  not have ACPI.
2510
2511	  There's no public spec for this chipset, and this functionality
2512	  is known to be incomplete.
2513
2514	  You should say N unless you know you need this.
2515
2516source "drivers/pci/Kconfig"
2517
2518config ISA_BUS
2519	bool "ISA-style bus support on modern systems" if EXPERT
2520	select ISA_BUS_API
2521	help
2522	  Enables ISA-style drivers on modern systems. This is necessary to
2523	  support PC/104 devices on X86_64 platforms.
2524
2525	  If unsure, say N.
2526
2527# x86_64 have no ISA slots, but can have ISA-style DMA.
2528config ISA_DMA_API
2529	bool "ISA-style DMA support" if (X86_64 && EXPERT)
2530	default y
2531	help
2532	  Enables ISA-style DMA support for devices requiring such controllers.
2533	  If unsure, say Y.
2534
2535if X86_32
2536
2537config ISA
2538	bool "ISA support"
2539	---help---
2540	  Find out whether you have ISA slots on your motherboard.  ISA is the
2541	  name of a bus system, i.e. the way the CPU talks to the other stuff
2542	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2543	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2544	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2545
2546config EISA
2547	bool "EISA support"
2548	depends on ISA
2549	---help---
2550	  The Extended Industry Standard Architecture (EISA) bus was
2551	  developed as an open alternative to the IBM MicroChannel bus.
2552
2553	  The EISA bus provided some of the features of the IBM MicroChannel
2554	  bus while maintaining backward compatibility with cards made for
2555	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2556	  1995 when it was made obsolete by the PCI bus.
2557
2558	  Say Y here if you are building a kernel for an EISA-based machine.
2559
2560	  Otherwise, say N.
2561
2562source "drivers/eisa/Kconfig"
2563
2564config SCx200
2565	tristate "NatSemi SCx200 support"
2566	---help---
2567	  This provides basic support for National Semiconductor's
2568	  (now AMD's) Geode processors.  The driver probes for the
2569	  PCI-IDs of several on-chip devices, so its a good dependency
2570	  for other scx200_* drivers.
2571
2572	  If compiled as a module, the driver is named scx200.
2573
2574config SCx200HR_TIMER
2575	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2576	depends on SCx200
2577	default y
2578	---help---
2579	  This driver provides a clocksource built upon the on-chip
2580	  27MHz high-resolution timer.  Its also a workaround for
2581	  NSC Geode SC-1100's buggy TSC, which loses time when the
2582	  processor goes idle (as is done by the scheduler).  The
2583	  other workaround is idle=poll boot option.
2584
2585config OLPC
2586	bool "One Laptop Per Child support"
2587	depends on !X86_PAE
2588	select GPIOLIB
2589	select OF
2590	select OF_PROMTREE
2591	select IRQ_DOMAIN
2592	---help---
2593	  Add support for detecting the unique features of the OLPC
2594	  XO hardware.
2595
2596config OLPC_XO1_PM
2597	bool "OLPC XO-1 Power Management"
2598	depends on OLPC && MFD_CS5535 && PM_SLEEP
2599	select MFD_CORE
2600	---help---
2601	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2602
2603config OLPC_XO1_RTC
2604	bool "OLPC XO-1 Real Time Clock"
2605	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2606	---help---
2607	  Add support for the XO-1 real time clock, which can be used as a
2608	  programmable wakeup source.
2609
2610config OLPC_XO1_SCI
2611	bool "OLPC XO-1 SCI extras"
2612	depends on OLPC && OLPC_XO1_PM
2613	depends on INPUT=y
2614	select POWER_SUPPLY
2615	select GPIO_CS5535
2616	select MFD_CORE
2617	---help---
2618	  Add support for SCI-based features of the OLPC XO-1 laptop:
2619	   - EC-driven system wakeups
2620	   - Power button
2621	   - Ebook switch
2622	   - Lid switch
2623	   - AC adapter status updates
2624	   - Battery status updates
2625
2626config OLPC_XO15_SCI
2627	bool "OLPC XO-1.5 SCI extras"
2628	depends on OLPC && ACPI
2629	select POWER_SUPPLY
2630	---help---
2631	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2632	   - EC-driven system wakeups
2633	   - AC adapter status updates
2634	   - Battery status updates
2635
2636config ALIX
2637	bool "PCEngines ALIX System Support (LED setup)"
2638	select GPIOLIB
2639	---help---
2640	  This option enables system support for the PCEngines ALIX.
2641	  At present this just sets up LEDs for GPIO control on
2642	  ALIX2/3/6 boards.  However, other system specific setup should
2643	  get added here.
2644
2645	  Note: You must still enable the drivers for GPIO and LED support
2646	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2647
2648	  Note: You have to set alix.force=1 for boards with Award BIOS.
2649
2650config NET5501
2651	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2652	select GPIOLIB
2653	---help---
2654	  This option enables system support for the Soekris Engineering net5501.
2655
2656config GEOS
2657	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2658	select GPIOLIB
2659	depends on DMI
2660	---help---
2661	  This option enables system support for the Traverse Technologies GEOS.
2662
2663config TS5500
2664	bool "Technologic Systems TS-5500 platform support"
2665	depends on MELAN
2666	select CHECK_SIGNATURE
2667	select NEW_LEDS
2668	select LEDS_CLASS
2669	---help---
2670	  This option enables system support for the Technologic Systems TS-5500.
2671
2672endif # X86_32
2673
2674config AMD_NB
2675	def_bool y
2676	depends on CPU_SUP_AMD && PCI
2677
2678source "drivers/pcmcia/Kconfig"
2679
2680config RAPIDIO
2681	tristate "RapidIO support"
2682	depends on PCI
2683	default n
2684	help
2685	  If enabled this option will include drivers and the core
2686	  infrastructure code to support RapidIO interconnect devices.
2687
2688source "drivers/rapidio/Kconfig"
2689
2690config X86_SYSFB
2691	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2692	help
2693	  Firmwares often provide initial graphics framebuffers so the BIOS,
2694	  bootloader or kernel can show basic video-output during boot for
2695	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2696	  Extensions and EFI-framebuffers for this, which are mostly limited
2697	  to x86.
2698	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2699	  framebuffers so the new generic system-framebuffer drivers can be
2700	  used on x86. If the framebuffer is not compatible with the generic
2701	  modes, it is adverticed as fallback platform framebuffer so legacy
2702	  drivers like efifb, vesafb and uvesafb can pick it up.
2703	  If this option is not selected, all system framebuffers are always
2704	  marked as fallback platform framebuffers as usual.
2705
2706	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2707	  not be able to pick up generic system framebuffers if this option
2708	  is selected. You are highly encouraged to enable simplefb as
2709	  replacement if you select this option. simplefb can correctly deal
2710	  with generic system framebuffers. But you should still keep vesafb
2711	  and others enabled as fallback if a system framebuffer is
2712	  incompatible with simplefb.
2713
2714	  If unsure, say Y.
2715
2716endmenu
2717
2718
2719menu "Executable file formats / Emulations"
2720
2721source "fs/Kconfig.binfmt"
2722
2723config IA32_EMULATION
2724	bool "IA32 Emulation"
2725	depends on X86_64
2726	select ARCH_WANT_OLD_COMPAT_IPC
2727	select BINFMT_ELF
2728	select COMPAT_BINFMT_ELF
2729	select COMPAT_OLD_SIGACTION
2730	---help---
2731	  Include code to run legacy 32-bit programs under a
2732	  64-bit kernel. You should likely turn this on, unless you're
2733	  100% sure that you don't have any 32-bit programs left.
2734
2735config IA32_AOUT
2736	tristate "IA32 a.out support"
2737	depends on IA32_EMULATION
2738	---help---
2739	  Support old a.out binaries in the 32bit emulation.
2740
2741config X86_X32
2742	bool "x32 ABI for 64-bit mode"
2743	depends on X86_64
2744	---help---
2745	  Include code to run binaries for the x32 native 32-bit ABI
2746	  for 64-bit processors.  An x32 process gets access to the
2747	  full 64-bit register file and wide data path while leaving
2748	  pointers at 32 bits for smaller memory footprint.
2749
2750	  You will need a recent binutils (2.22 or later) with
2751	  elf32_x86_64 support enabled to compile a kernel with this
2752	  option set.
2753
2754config COMPAT_32
2755	def_bool y
2756	depends on IA32_EMULATION || X86_32
2757	select HAVE_UID16
2758	select OLD_SIGSUSPEND3
2759
2760config COMPAT
2761	def_bool y
2762	depends on IA32_EMULATION || X86_X32
2763
2764if COMPAT
2765config COMPAT_FOR_U64_ALIGNMENT
2766	def_bool y
2767
2768config SYSVIPC_COMPAT
2769	def_bool y
2770	depends on SYSVIPC
2771
2772config KEYS_COMPAT
2773	def_bool y
2774	depends on KEYS
2775endif
2776
2777endmenu
2778
2779
2780config HAVE_ATOMIC_IOMAP
2781	def_bool y
2782	depends on X86_32
2783
2784config X86_DEV_DMA_OPS
2785	bool
2786	depends on X86_64 || STA2X11
2787
2788config X86_DMA_REMAP
2789	bool
2790	depends on STA2X11
2791
2792config PMC_ATOM
2793	def_bool y
2794        depends on PCI
2795
2796source "net/Kconfig"
2797
2798source "drivers/Kconfig"
2799
2800source "drivers/firmware/Kconfig"
2801
2802source "fs/Kconfig"
2803
2804source "arch/x86/Kconfig.debug"
2805
2806source "security/Kconfig"
2807
2808source "crypto/Kconfig"
2809
2810source "arch/x86/kvm/Kconfig"
2811
2812source "lib/Kconfig"
2813