xref: /linux/arch/x86/Kconfig (revision ffd81dcfef85a33729f90e4acd2f61a68e56b993)
1# SPDX-License-Identifier: GPL-2.0
2# Select 32 or 64 bit
3config 64BIT
4	bool "64-bit kernel" if ARCH = "x86"
5	default ARCH != "i386"
6	---help---
7	  Say yes to build a 64-bit kernel - formerly known as x86_64
8	  Say no to build a 32-bit kernel - formerly known as i386
9
10config X86_32
11	def_bool y
12	depends on !64BIT
13	# Options that are inherently 32-bit kernel only:
14	select ARCH_WANT_IPC_PARSE_VERSION
15	select CLKSRC_I8253
16	select CLONE_BACKWARDS
17	select HAVE_AOUT
18	select HAVE_GENERIC_DMA_COHERENT
19	select MODULES_USE_ELF_REL
20	select OLD_SIGACTION
21
22config X86_64
23	def_bool y
24	depends on 64BIT
25	# Options that are inherently 64-bit kernel only:
26	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
27	select ARCH_SUPPORTS_INT128
28	select ARCH_USE_CMPXCHG_LOCKREF
29	select HAVE_ARCH_SOFT_DIRTY
30	select MODULES_USE_ELF_RELA
31	select X86_DEV_DMA_OPS
32
33#
34# Arch settings
35#
36# ( Note that options that are marked 'if X86_64' could in principle be
37#   ported to 32-bit as well. )
38#
39config X86
40	def_bool y
41	#
42	# Note: keep this list sorted alphabetically
43	#
44	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
45	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
46	select ANON_INODES
47	select ARCH_CLOCKSOURCE_DATA
48	select ARCH_DISCARD_MEMBLOCK
49	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
50	select ARCH_HAS_DEBUG_VIRTUAL
51	select ARCH_HAS_DEVMEM_IS_ALLOWED
52	select ARCH_HAS_ELF_RANDOMIZE
53	select ARCH_HAS_FAST_MULTIPLIER
54	select ARCH_HAS_FORTIFY_SOURCE
55	select ARCH_HAS_GCOV_PROFILE_ALL
56	select ARCH_HAS_KCOV			if X86_64
57	select ARCH_HAS_PMEM_API		if X86_64
58	select ARCH_HAS_REFCOUNT
59	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
60	select ARCH_HAS_SET_MEMORY
61	select ARCH_HAS_SG_CHAIN
62	select ARCH_HAS_STRICT_KERNEL_RWX
63	select ARCH_HAS_STRICT_MODULE_RWX
64	select ARCH_HAS_UBSAN_SANITIZE_ALL
65	select ARCH_HAS_ZONE_DEVICE		if X86_64
66	select ARCH_HAVE_NMI_SAFE_CMPXCHG
67	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
68	select ARCH_MIGHT_HAVE_PC_PARPORT
69	select ARCH_MIGHT_HAVE_PC_SERIO
70	select ARCH_SUPPORTS_ATOMIC_RMW
71	select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
72	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
73	select ARCH_USE_BUILTIN_BSWAP
74	select ARCH_USE_QUEUED_RWLOCKS
75	select ARCH_USE_QUEUED_SPINLOCKS
76	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
77	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
78	select ARCH_WANTS_THP_SWAP		if X86_64
79	select BUILDTIME_EXTABLE_SORT
80	select CLKEVT_I8253
81	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
82	select CLOCKSOURCE_WATCHDOG
83	select DCACHE_WORD_ACCESS
84	select EDAC_ATOMIC_SCRUB
85	select EDAC_SUPPORT
86	select GENERIC_CLOCKEVENTS
87	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
88	select GENERIC_CLOCKEVENTS_MIN_ADJUST
89	select GENERIC_CMOS_UPDATE
90	select GENERIC_CPU_AUTOPROBE
91	select GENERIC_CPU_VULNERABILITIES
92	select GENERIC_EARLY_IOREMAP
93	select GENERIC_FIND_FIRST_BIT
94	select GENERIC_IOMAP
95	select GENERIC_IRQ_EFFECTIVE_AFF_MASK	if SMP
96	select GENERIC_IRQ_MATRIX_ALLOCATOR	if X86_LOCAL_APIC
97	select GENERIC_IRQ_MIGRATION		if SMP
98	select GENERIC_IRQ_PROBE
99	select GENERIC_IRQ_RESERVATION_MODE
100	select GENERIC_IRQ_SHOW
101	select GENERIC_PENDING_IRQ		if SMP
102	select GENERIC_SMP_IDLE_THREAD
103	select GENERIC_STRNCPY_FROM_USER
104	select GENERIC_STRNLEN_USER
105	select GENERIC_TIME_VSYSCALL
106	select HARDLOCKUP_CHECK_TIMESTAMP	if X86_64
107	select HAVE_ACPI_APEI			if ACPI
108	select HAVE_ACPI_APEI_NMI		if ACPI
109	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
110	select HAVE_ARCH_AUDITSYSCALL
111	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
112	select HAVE_ARCH_JUMP_LABEL
113	select HAVE_ARCH_KASAN			if X86_64
114	select HAVE_ARCH_KGDB
115	select HAVE_ARCH_MMAP_RND_BITS		if MMU
116	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
117	select HAVE_ARCH_COMPAT_MMAP_BASES	if MMU && COMPAT
118	select HAVE_ARCH_SECCOMP_FILTER
119	select HAVE_ARCH_TRACEHOOK
120	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
121	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
122	select HAVE_ARCH_VMAP_STACK		if X86_64
123	select HAVE_ARCH_WITHIN_STACK_FRAMES
124	select HAVE_CC_STACKPROTECTOR
125	select HAVE_CMPXCHG_DOUBLE
126	select HAVE_CMPXCHG_LOCAL
127	select HAVE_CONTEXT_TRACKING		if X86_64
128	select HAVE_COPY_THREAD_TLS
129	select HAVE_C_RECORDMCOUNT
130	select HAVE_DEBUG_KMEMLEAK
131	select HAVE_DEBUG_STACKOVERFLOW
132	select HAVE_DMA_API_DEBUG
133	select HAVE_DMA_CONTIGUOUS
134	select HAVE_DYNAMIC_FTRACE
135	select HAVE_DYNAMIC_FTRACE_WITH_REGS
136	select HAVE_EBPF_JIT			if X86_64
137	select HAVE_EFFICIENT_UNALIGNED_ACCESS
138	select HAVE_EXIT_THREAD
139	select HAVE_FENTRY			if X86_64 || DYNAMIC_FTRACE
140	select HAVE_FTRACE_MCOUNT_RECORD
141	select HAVE_FUNCTION_GRAPH_TRACER
142	select HAVE_FUNCTION_TRACER
143	select HAVE_GCC_PLUGINS
144	select HAVE_HW_BREAKPOINT
145	select HAVE_IDE
146	select HAVE_IOREMAP_PROT
147	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
148	select HAVE_IRQ_TIME_ACCOUNTING
149	select HAVE_KERNEL_BZIP2
150	select HAVE_KERNEL_GZIP
151	select HAVE_KERNEL_LZ4
152	select HAVE_KERNEL_LZMA
153	select HAVE_KERNEL_LZO
154	select HAVE_KERNEL_XZ
155	select HAVE_KPROBES
156	select HAVE_KPROBES_ON_FTRACE
157	select HAVE_KRETPROBES
158	select HAVE_KVM
159	select HAVE_LIVEPATCH			if X86_64
160	select HAVE_MEMBLOCK
161	select HAVE_MEMBLOCK_NODE_MAP
162	select HAVE_MIXED_BREAKPOINTS_REGS
163	select HAVE_MOD_ARCH_SPECIFIC
164	select HAVE_NMI
165	select HAVE_OPROFILE
166	select HAVE_OPTPROBES
167	select HAVE_PCSPKR_PLATFORM
168	select HAVE_PERF_EVENTS
169	select HAVE_PERF_EVENTS_NMI
170	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
171	select HAVE_PERF_REGS
172	select HAVE_PERF_USER_STACK_DUMP
173	select HAVE_RCU_TABLE_FREE
174	select HAVE_REGS_AND_STACK_ACCESS_API
175	select HAVE_RELIABLE_STACKTRACE		if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION
176	select HAVE_STACK_VALIDATION		if X86_64
177	select HAVE_SYSCALL_TRACEPOINTS
178	select HAVE_UNSTABLE_SCHED_CLOCK
179	select HAVE_USER_RETURN_NOTIFIER
180	select IRQ_FORCED_THREADING
181	select PCI_LOCKLESS_CONFIG
182	select PERF_EVENTS
183	select RTC_LIB
184	select RTC_MC146818_LIB
185	select SPARSE_IRQ
186	select SRCU
187	select SYSCTL_EXCEPTION_TRACE
188	select THREAD_INFO_IN_TASK
189	select USER_STACKTRACE_SUPPORT
190	select VIRT_TO_BUS
191	select X86_FEATURE_NAMES		if PROC_FS
192
193config INSTRUCTION_DECODER
194	def_bool y
195	depends on KPROBES || PERF_EVENTS || UPROBES
196
197config OUTPUT_FORMAT
198	string
199	default "elf32-i386" if X86_32
200	default "elf64-x86-64" if X86_64
201
202config ARCH_DEFCONFIG
203	string
204	default "arch/x86/configs/i386_defconfig" if X86_32
205	default "arch/x86/configs/x86_64_defconfig" if X86_64
206
207config LOCKDEP_SUPPORT
208	def_bool y
209
210config STACKTRACE_SUPPORT
211	def_bool y
212
213config MMU
214	def_bool y
215
216config ARCH_MMAP_RND_BITS_MIN
217	default 28 if 64BIT
218	default 8
219
220config ARCH_MMAP_RND_BITS_MAX
221	default 32 if 64BIT
222	default 16
223
224config ARCH_MMAP_RND_COMPAT_BITS_MIN
225	default 8
226
227config ARCH_MMAP_RND_COMPAT_BITS_MAX
228	default 16
229
230config SBUS
231	bool
232
233config NEED_DMA_MAP_STATE
234	def_bool y
235	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
236
237config NEED_SG_DMA_LENGTH
238	def_bool y
239
240config GENERIC_ISA_DMA
241	def_bool y
242	depends on ISA_DMA_API
243
244config GENERIC_BUG
245	def_bool y
246	depends on BUG
247	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
248
249config GENERIC_BUG_RELATIVE_POINTERS
250	bool
251
252config GENERIC_HWEIGHT
253	def_bool y
254
255config ARCH_MAY_HAVE_PC_FDC
256	def_bool y
257	depends on ISA_DMA_API
258
259config RWSEM_XCHGADD_ALGORITHM
260	def_bool y
261
262config GENERIC_CALIBRATE_DELAY
263	def_bool y
264
265config ARCH_HAS_CPU_RELAX
266	def_bool y
267
268config ARCH_HAS_CACHE_LINE_SIZE
269	def_bool y
270
271config HAVE_SETUP_PER_CPU_AREA
272	def_bool y
273
274config NEED_PER_CPU_EMBED_FIRST_CHUNK
275	def_bool y
276
277config NEED_PER_CPU_PAGE_FIRST_CHUNK
278	def_bool y
279
280config ARCH_HIBERNATION_POSSIBLE
281	def_bool y
282
283config ARCH_SUSPEND_POSSIBLE
284	def_bool y
285
286config ARCH_WANT_HUGE_PMD_SHARE
287	def_bool y
288
289config ARCH_WANT_GENERAL_HUGETLB
290	def_bool y
291
292config ZONE_DMA32
293	def_bool y if X86_64
294
295config AUDIT_ARCH
296	def_bool y if X86_64
297
298config ARCH_SUPPORTS_OPTIMIZED_INLINING
299	def_bool y
300
301config ARCH_SUPPORTS_DEBUG_PAGEALLOC
302	def_bool y
303
304config KASAN_SHADOW_OFFSET
305	hex
306	depends on KASAN
307	default 0xdffffc0000000000
308
309config HAVE_INTEL_TXT
310	def_bool y
311	depends on INTEL_IOMMU && ACPI
312
313config X86_32_SMP
314	def_bool y
315	depends on X86_32 && SMP
316
317config X86_64_SMP
318	def_bool y
319	depends on X86_64 && SMP
320
321config X86_32_LAZY_GS
322	def_bool y
323	depends on X86_32 && !CC_STACKPROTECTOR
324
325config ARCH_SUPPORTS_UPROBES
326	def_bool y
327
328config FIX_EARLYCON_MEM
329	def_bool y
330
331config PGTABLE_LEVELS
332	int
333	default 5 if X86_5LEVEL
334	default 4 if X86_64
335	default 3 if X86_PAE
336	default 2
337
338source "init/Kconfig"
339source "kernel/Kconfig.freezer"
340
341menu "Processor type and features"
342
343config ZONE_DMA
344	bool "DMA memory allocation support" if EXPERT
345	default y
346	help
347	  DMA memory allocation support allows devices with less than 32-bit
348	  addressing to allocate within the first 16MB of address space.
349	  Disable if no such devices will be used.
350
351	  If unsure, say Y.
352
353config SMP
354	bool "Symmetric multi-processing support"
355	---help---
356	  This enables support for systems with more than one CPU. If you have
357	  a system with only one CPU, say N. If you have a system with more
358	  than one CPU, say Y.
359
360	  If you say N here, the kernel will run on uni- and multiprocessor
361	  machines, but will use only one CPU of a multiprocessor machine. If
362	  you say Y here, the kernel will run on many, but not all,
363	  uniprocessor machines. On a uniprocessor machine, the kernel
364	  will run faster if you say N here.
365
366	  Note that if you say Y here and choose architecture "586" or
367	  "Pentium" under "Processor family", the kernel will not work on 486
368	  architectures. Similarly, multiprocessor kernels for the "PPro"
369	  architecture may not work on all Pentium based boards.
370
371	  People using multiprocessor machines who say Y here should also say
372	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
373	  Management" code will be disabled if you say Y here.
374
375	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
376	  <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
377	  <http://www.tldp.org/docs.html#howto>.
378
379	  If you don't know what to do here, say N.
380
381config X86_FEATURE_NAMES
382	bool "Processor feature human-readable names" if EMBEDDED
383	default y
384	---help---
385	  This option compiles in a table of x86 feature bits and corresponding
386	  names.  This is required to support /proc/cpuinfo and a few kernel
387	  messages.  You can disable this to save space, at the expense of
388	  making those few kernel messages show numeric feature bits instead.
389
390	  If in doubt, say Y.
391
392config X86_FAST_FEATURE_TESTS
393	bool "Fast CPU feature tests" if EMBEDDED
394	default y
395	---help---
396	  Some fast-paths in the kernel depend on the capabilities of the CPU.
397	  Say Y here for the kernel to patch in the appropriate code at runtime
398	  based on the capabilities of the CPU. The infrastructure for patching
399	  code at runtime takes up some additional space; space-constrained
400	  embedded systems may wish to say N here to produce smaller, slightly
401	  slower code.
402
403config X86_X2APIC
404	bool "Support x2apic"
405	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
406	---help---
407	  This enables x2apic support on CPUs that have this feature.
408
409	  This allows 32-bit apic IDs (so it can support very large systems),
410	  and accesses the local apic via MSRs not via mmio.
411
412	  If you don't know what to do here, say N.
413
414config X86_MPPARSE
415	bool "Enable MPS table" if ACPI || SFI
416	default y
417	depends on X86_LOCAL_APIC
418	---help---
419	  For old smp systems that do not have proper acpi support. Newer systems
420	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
421
422config X86_BIGSMP
423	bool "Support for big SMP systems with more than 8 CPUs"
424	depends on X86_32 && SMP
425	---help---
426	  This option is needed for the systems that have more than 8 CPUs
427
428config GOLDFISH
429       def_bool y
430       depends on X86_GOLDFISH
431
432config RETPOLINE
433	bool "Avoid speculative indirect branches in kernel"
434	default y
435	help
436	  Compile kernel with the retpoline compiler options to guard against
437	  kernel-to-user data leaks by avoiding speculative indirect
438	  branches. Requires a compiler with -mindirect-branch=thunk-extern
439	  support for full protection. The kernel may run slower.
440
441	  Without compiler support, at least indirect branches in assembler
442	  code are eliminated. Since this includes the syscall entry path,
443	  it is not entirely pointless.
444
445config INTEL_RDT
446	bool "Intel Resource Director Technology support"
447	default n
448	depends on X86 && CPU_SUP_INTEL
449	select KERNFS
450	help
451	  Select to enable resource allocation and monitoring which are
452	  sub-features of Intel Resource Director Technology(RDT). More
453	  information about RDT can be found in the Intel x86
454	  Architecture Software Developer Manual.
455
456	  Say N if unsure.
457
458if X86_32
459config X86_EXTENDED_PLATFORM
460	bool "Support for extended (non-PC) x86 platforms"
461	default y
462	---help---
463	  If you disable this option then the kernel will only support
464	  standard PC platforms. (which covers the vast majority of
465	  systems out there.)
466
467	  If you enable this option then you'll be able to select support
468	  for the following (non-PC) 32 bit x86 platforms:
469		Goldfish (Android emulator)
470		AMD Elan
471		RDC R-321x SoC
472		SGI 320/540 (Visual Workstation)
473		STA2X11-based (e.g. Northville)
474		Moorestown MID devices
475
476	  If you have one of these systems, or if you want to build a
477	  generic distribution kernel, say Y here - otherwise say N.
478endif
479
480if X86_64
481config X86_EXTENDED_PLATFORM
482	bool "Support for extended (non-PC) x86 platforms"
483	default y
484	---help---
485	  If you disable this option then the kernel will only support
486	  standard PC platforms. (which covers the vast majority of
487	  systems out there.)
488
489	  If you enable this option then you'll be able to select support
490	  for the following (non-PC) 64 bit x86 platforms:
491		Numascale NumaChip
492		ScaleMP vSMP
493		SGI Ultraviolet
494
495	  If you have one of these systems, or if you want to build a
496	  generic distribution kernel, say Y here - otherwise say N.
497endif
498# This is an alphabetically sorted list of 64 bit extended platforms
499# Please maintain the alphabetic order if and when there are additions
500config X86_NUMACHIP
501	bool "Numascale NumaChip"
502	depends on X86_64
503	depends on X86_EXTENDED_PLATFORM
504	depends on NUMA
505	depends on SMP
506	depends on X86_X2APIC
507	depends on PCI_MMCONFIG
508	---help---
509	  Adds support for Numascale NumaChip large-SMP systems. Needed to
510	  enable more than ~168 cores.
511	  If you don't have one of these, you should say N here.
512
513config X86_VSMP
514	bool "ScaleMP vSMP"
515	select HYPERVISOR_GUEST
516	select PARAVIRT
517	depends on X86_64 && PCI
518	depends on X86_EXTENDED_PLATFORM
519	depends on SMP
520	---help---
521	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
522	  supposed to run on these EM64T-based machines.  Only choose this option
523	  if you have one of these machines.
524
525config X86_UV
526	bool "SGI Ultraviolet"
527	depends on X86_64
528	depends on X86_EXTENDED_PLATFORM
529	depends on NUMA
530	depends on EFI
531	depends on X86_X2APIC
532	depends on PCI
533	---help---
534	  This option is needed in order to support SGI Ultraviolet systems.
535	  If you don't have one of these, you should say N here.
536
537# Following is an alphabetically sorted list of 32 bit extended platforms
538# Please maintain the alphabetic order if and when there are additions
539
540config X86_GOLDFISH
541       bool "Goldfish (Virtual Platform)"
542       depends on X86_EXTENDED_PLATFORM
543       ---help---
544	 Enable support for the Goldfish virtual platform used primarily
545	 for Android development. Unless you are building for the Android
546	 Goldfish emulator say N here.
547
548config X86_INTEL_CE
549	bool "CE4100 TV platform"
550	depends on PCI
551	depends on PCI_GODIRECT
552	depends on X86_IO_APIC
553	depends on X86_32
554	depends on X86_EXTENDED_PLATFORM
555	select X86_REBOOTFIXUPS
556	select OF
557	select OF_EARLY_FLATTREE
558	---help---
559	  Select for the Intel CE media processor (CE4100) SOC.
560	  This option compiles in support for the CE4100 SOC for settop
561	  boxes and media devices.
562
563config X86_INTEL_MID
564	bool "Intel MID platform support"
565	depends on X86_EXTENDED_PLATFORM
566	depends on X86_PLATFORM_DEVICES
567	depends on PCI
568	depends on X86_64 || (PCI_GOANY && X86_32)
569	depends on X86_IO_APIC
570	select SFI
571	select I2C
572	select DW_APB_TIMER
573	select APB_TIMER
574	select INTEL_SCU_IPC
575	select MFD_INTEL_MSIC
576	---help---
577	  Select to build a kernel capable of supporting Intel MID (Mobile
578	  Internet Device) platform systems which do not have the PCI legacy
579	  interfaces. If you are building for a PC class system say N here.
580
581	  Intel MID platforms are based on an Intel processor and chipset which
582	  consume less power than most of the x86 derivatives.
583
584config X86_INTEL_QUARK
585	bool "Intel Quark platform support"
586	depends on X86_32
587	depends on X86_EXTENDED_PLATFORM
588	depends on X86_PLATFORM_DEVICES
589	depends on X86_TSC
590	depends on PCI
591	depends on PCI_GOANY
592	depends on X86_IO_APIC
593	select IOSF_MBI
594	select INTEL_IMR
595	select COMMON_CLK
596	---help---
597	  Select to include support for Quark X1000 SoC.
598	  Say Y here if you have a Quark based system such as the Arduino
599	  compatible Intel Galileo.
600
601config X86_INTEL_LPSS
602	bool "Intel Low Power Subsystem Support"
603	depends on X86 && ACPI
604	select COMMON_CLK
605	select PINCTRL
606	select IOSF_MBI
607	---help---
608	  Select to build support for Intel Low Power Subsystem such as
609	  found on Intel Lynxpoint PCH. Selecting this option enables
610	  things like clock tree (common clock framework) and pincontrol
611	  which are needed by the LPSS peripheral drivers.
612
613config X86_AMD_PLATFORM_DEVICE
614	bool "AMD ACPI2Platform devices support"
615	depends on ACPI
616	select COMMON_CLK
617	select PINCTRL
618	---help---
619	  Select to interpret AMD specific ACPI device to platform device
620	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
621	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
622	  implemented under PINCTRL subsystem.
623
624config IOSF_MBI
625	tristate "Intel SoC IOSF Sideband support for SoC platforms"
626	depends on PCI
627	---help---
628	  This option enables sideband register access support for Intel SoC
629	  platforms. On these platforms the IOSF sideband is used in lieu of
630	  MSR's for some register accesses, mostly but not limited to thermal
631	  and power. Drivers may query the availability of this device to
632	  determine if they need the sideband in order to work on these
633	  platforms. The sideband is available on the following SoC products.
634	  This list is not meant to be exclusive.
635	   - BayTrail
636	   - Braswell
637	   - Quark
638
639	  You should say Y if you are running a kernel on one of these SoC's.
640
641config IOSF_MBI_DEBUG
642	bool "Enable IOSF sideband access through debugfs"
643	depends on IOSF_MBI && DEBUG_FS
644	---help---
645	  Select this option to expose the IOSF sideband access registers (MCR,
646	  MDR, MCRX) through debugfs to write and read register information from
647	  different units on the SoC. This is most useful for obtaining device
648	  state information for debug and analysis. As this is a general access
649	  mechanism, users of this option would have specific knowledge of the
650	  device they want to access.
651
652	  If you don't require the option or are in doubt, say N.
653
654config X86_RDC321X
655	bool "RDC R-321x SoC"
656	depends on X86_32
657	depends on X86_EXTENDED_PLATFORM
658	select M486
659	select X86_REBOOTFIXUPS
660	---help---
661	  This option is needed for RDC R-321x system-on-chip, also known
662	  as R-8610-(G).
663	  If you don't have one of these chips, you should say N here.
664
665config X86_32_NON_STANDARD
666	bool "Support non-standard 32-bit SMP architectures"
667	depends on X86_32 && SMP
668	depends on X86_EXTENDED_PLATFORM
669	---help---
670	  This option compiles in the bigsmp and STA2X11 default
671	  subarchitectures.  It is intended for a generic binary
672	  kernel. If you select them all, kernel will probe it one by
673	  one and will fallback to default.
674
675# Alphabetically sorted list of Non standard 32 bit platforms
676
677config X86_SUPPORTS_MEMORY_FAILURE
678	def_bool y
679	# MCE code calls memory_failure():
680	depends on X86_MCE
681	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
682	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
683	depends on X86_64 || !SPARSEMEM
684	select ARCH_SUPPORTS_MEMORY_FAILURE
685
686config STA2X11
687	bool "STA2X11 Companion Chip Support"
688	depends on X86_32_NON_STANDARD && PCI
689	select X86_DEV_DMA_OPS
690	select X86_DMA_REMAP
691	select SWIOTLB
692	select MFD_STA2X11
693	select GPIOLIB
694	default n
695	---help---
696	  This adds support for boards based on the STA2X11 IO-Hub,
697	  a.k.a. "ConneXt". The chip is used in place of the standard
698	  PC chipset, so all "standard" peripherals are missing. If this
699	  option is selected the kernel will still be able to boot on
700	  standard PC machines.
701
702config X86_32_IRIS
703	tristate "Eurobraille/Iris poweroff module"
704	depends on X86_32
705	---help---
706	  The Iris machines from EuroBraille do not have APM or ACPI support
707	  to shut themselves down properly.  A special I/O sequence is
708	  needed to do so, which is what this module does at
709	  kernel shutdown.
710
711	  This is only for Iris machines from EuroBraille.
712
713	  If unused, say N.
714
715config SCHED_OMIT_FRAME_POINTER
716	def_bool y
717	prompt "Single-depth WCHAN output"
718	depends on X86
719	---help---
720	  Calculate simpler /proc/<PID>/wchan values. If this option
721	  is disabled then wchan values will recurse back to the
722	  caller function. This provides more accurate wchan values,
723	  at the expense of slightly more scheduling overhead.
724
725	  If in doubt, say "Y".
726
727menuconfig HYPERVISOR_GUEST
728	bool "Linux guest support"
729	---help---
730	  Say Y here to enable options for running Linux under various hyper-
731	  visors. This option enables basic hypervisor detection and platform
732	  setup.
733
734	  If you say N, all options in this submenu will be skipped and
735	  disabled, and Linux guest support won't be built in.
736
737if HYPERVISOR_GUEST
738
739config PARAVIRT
740	bool "Enable paravirtualization code"
741	---help---
742	  This changes the kernel so it can modify itself when it is run
743	  under a hypervisor, potentially improving performance significantly
744	  over full virtualization.  However, when run without a hypervisor
745	  the kernel is theoretically slower and slightly larger.
746
747config PARAVIRT_DEBUG
748	bool "paravirt-ops debugging"
749	depends on PARAVIRT && DEBUG_KERNEL
750	---help---
751	  Enable to debug paravirt_ops internals.  Specifically, BUG if
752	  a paravirt_op is missing when it is called.
753
754config PARAVIRT_SPINLOCKS
755	bool "Paravirtualization layer for spinlocks"
756	depends on PARAVIRT && SMP
757	---help---
758	  Paravirtualized spinlocks allow a pvops backend to replace the
759	  spinlock implementation with something virtualization-friendly
760	  (for example, block the virtual CPU rather than spinning).
761
762	  It has a minimal impact on native kernels and gives a nice performance
763	  benefit on paravirtualized KVM / Xen kernels.
764
765	  If you are unsure how to answer this question, answer Y.
766
767config QUEUED_LOCK_STAT
768	bool "Paravirt queued spinlock statistics"
769	depends on PARAVIRT_SPINLOCKS && DEBUG_FS
770	---help---
771	  Enable the collection of statistical data on the slowpath
772	  behavior of paravirtualized queued spinlocks and report
773	  them on debugfs.
774
775source "arch/x86/xen/Kconfig"
776
777config KVM_GUEST
778	bool "KVM Guest support (including kvmclock)"
779	depends on PARAVIRT
780	select PARAVIRT_CLOCK
781	default y
782	---help---
783	  This option enables various optimizations for running under the KVM
784	  hypervisor. It includes a paravirtualized clock, so that instead
785	  of relying on a PIT (or probably other) emulation by the
786	  underlying device model, the host provides the guest with
787	  timing infrastructure such as time of day, and system time
788
789config KVM_DEBUG_FS
790	bool "Enable debug information for KVM Guests in debugfs"
791	depends on KVM_GUEST && DEBUG_FS
792	default n
793	---help---
794	  This option enables collection of various statistics for KVM guest.
795	  Statistics are displayed in debugfs filesystem. Enabling this option
796	  may incur significant overhead.
797
798config PARAVIRT_TIME_ACCOUNTING
799	bool "Paravirtual steal time accounting"
800	depends on PARAVIRT
801	default n
802	---help---
803	  Select this option to enable fine granularity task steal time
804	  accounting. Time spent executing other tasks in parallel with
805	  the current vCPU is discounted from the vCPU power. To account for
806	  that, there can be a small performance impact.
807
808	  If in doubt, say N here.
809
810config PARAVIRT_CLOCK
811	bool
812
813endif #HYPERVISOR_GUEST
814
815config NO_BOOTMEM
816	def_bool y
817
818source "arch/x86/Kconfig.cpu"
819
820config HPET_TIMER
821	def_bool X86_64
822	prompt "HPET Timer Support" if X86_32
823	---help---
824	  Use the IA-PC HPET (High Precision Event Timer) to manage
825	  time in preference to the PIT and RTC, if a HPET is
826	  present.
827	  HPET is the next generation timer replacing legacy 8254s.
828	  The HPET provides a stable time base on SMP
829	  systems, unlike the TSC, but it is more expensive to access,
830	  as it is off-chip.  The interface used is documented
831	  in the HPET spec, revision 1.
832
833	  You can safely choose Y here.  However, HPET will only be
834	  activated if the platform and the BIOS support this feature.
835	  Otherwise the 8254 will be used for timing services.
836
837	  Choose N to continue using the legacy 8254 timer.
838
839config HPET_EMULATE_RTC
840	def_bool y
841	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
842
843config APB_TIMER
844       def_bool y if X86_INTEL_MID
845       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
846       select DW_APB_TIMER
847       depends on X86_INTEL_MID && SFI
848       help
849         APB timer is the replacement for 8254, HPET on X86 MID platforms.
850         The APBT provides a stable time base on SMP
851         systems, unlike the TSC, but it is more expensive to access,
852         as it is off-chip. APB timers are always running regardless of CPU
853         C states, they are used as per CPU clockevent device when possible.
854
855# Mark as expert because too many people got it wrong.
856# The code disables itself when not needed.
857config DMI
858	default y
859	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
860	bool "Enable DMI scanning" if EXPERT
861	---help---
862	  Enabled scanning of DMI to identify machine quirks. Say Y
863	  here unless you have verified that your setup is not
864	  affected by entries in the DMI blacklist. Required by PNP
865	  BIOS code.
866
867config GART_IOMMU
868	bool "Old AMD GART IOMMU support"
869	select SWIOTLB
870	depends on X86_64 && PCI && AMD_NB
871	---help---
872	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
873	  GART based hardware IOMMUs.
874
875	  The GART supports full DMA access for devices with 32-bit access
876	  limitations, on systems with more than 3 GB. This is usually needed
877	  for USB, sound, many IDE/SATA chipsets and some other devices.
878
879	  Newer systems typically have a modern AMD IOMMU, supported via
880	  the CONFIG_AMD_IOMMU=y config option.
881
882	  In normal configurations this driver is only active when needed:
883	  there's more than 3 GB of memory and the system contains a
884	  32-bit limited device.
885
886	  If unsure, say Y.
887
888config CALGARY_IOMMU
889	bool "IBM Calgary IOMMU support"
890	select SWIOTLB
891	depends on X86_64 && PCI
892	---help---
893	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
894	  systems. Needed to run systems with more than 3GB of memory
895	  properly with 32-bit PCI devices that do not support DAC
896	  (Double Address Cycle). Calgary also supports bus level
897	  isolation, where all DMAs pass through the IOMMU.  This
898	  prevents them from going anywhere except their intended
899	  destination. This catches hard-to-find kernel bugs and
900	  mis-behaving drivers and devices that do not use the DMA-API
901	  properly to set up their DMA buffers.  The IOMMU can be
902	  turned off at boot time with the iommu=off parameter.
903	  Normally the kernel will make the right choice by itself.
904	  If unsure, say Y.
905
906config CALGARY_IOMMU_ENABLED_BY_DEFAULT
907	def_bool y
908	prompt "Should Calgary be enabled by default?"
909	depends on CALGARY_IOMMU
910	---help---
911	  Should Calgary be enabled by default? if you choose 'y', Calgary
912	  will be used (if it exists). If you choose 'n', Calgary will not be
913	  used even if it exists. If you choose 'n' and would like to use
914	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
915	  If unsure, say Y.
916
917# need this always selected by IOMMU for the VIA workaround
918config SWIOTLB
919	def_bool y if X86_64
920	---help---
921	  Support for software bounce buffers used on x86-64 systems
922	  which don't have a hardware IOMMU. Using this PCI devices
923	  which can only access 32-bits of memory can be used on systems
924	  with more than 3 GB of memory.
925	  If unsure, say Y.
926
927config IOMMU_HELPER
928	def_bool y
929	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
930
931config MAXSMP
932	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
933	depends on X86_64 && SMP && DEBUG_KERNEL
934	select CPUMASK_OFFSTACK
935	---help---
936	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
937	  If unsure, say N.
938
939config NR_CPUS
940	int "Maximum number of CPUs" if SMP && !MAXSMP
941	range 2 8 if SMP && X86_32 && !X86_BIGSMP
942	range 2 64 if SMP && X86_32 && X86_BIGSMP
943	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK && X86_64
944	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
945	default "1" if !SMP
946	default "8192" if MAXSMP
947	default "32" if SMP && X86_BIGSMP
948	default "8" if SMP && X86_32
949	default "64" if SMP
950	---help---
951	  This allows you to specify the maximum number of CPUs which this
952	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
953	  supported value is 8192, otherwise the maximum value is 512.  The
954	  minimum value which makes sense is 2.
955
956	  This is purely to save memory - each supported CPU adds
957	  approximately eight kilobytes to the kernel image.
958
959config SCHED_SMT
960	bool "SMT (Hyperthreading) scheduler support"
961	depends on SMP
962	---help---
963	  SMT scheduler support improves the CPU scheduler's decision making
964	  when dealing with Intel Pentium 4 chips with HyperThreading at a
965	  cost of slightly increased overhead in some places. If unsure say
966	  N here.
967
968config SCHED_MC
969	def_bool y
970	prompt "Multi-core scheduler support"
971	depends on SMP
972	---help---
973	  Multi-core scheduler support improves the CPU scheduler's decision
974	  making when dealing with multi-core CPU chips at a cost of slightly
975	  increased overhead in some places. If unsure say N here.
976
977config SCHED_MC_PRIO
978	bool "CPU core priorities scheduler support"
979	depends on SCHED_MC && CPU_SUP_INTEL
980	select X86_INTEL_PSTATE
981	select CPU_FREQ
982	default y
983	---help---
984	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
985	  core ordering determined at manufacturing time, which allows
986	  certain cores to reach higher turbo frequencies (when running
987	  single threaded workloads) than others.
988
989	  Enabling this kernel feature teaches the scheduler about
990	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
991	  scheduler's CPU selection logic accordingly, so that higher
992	  overall system performance can be achieved.
993
994	  This feature will have no effect on CPUs without this feature.
995
996	  If unsure say Y here.
997
998source "kernel/Kconfig.preempt"
999
1000config UP_LATE_INIT
1001       def_bool y
1002       depends on !SMP && X86_LOCAL_APIC
1003
1004config X86_UP_APIC
1005	bool "Local APIC support on uniprocessors" if !PCI_MSI
1006	default PCI_MSI
1007	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
1008	---help---
1009	  A local APIC (Advanced Programmable Interrupt Controller) is an
1010	  integrated interrupt controller in the CPU. If you have a single-CPU
1011	  system which has a processor with a local APIC, you can say Y here to
1012	  enable and use it. If you say Y here even though your machine doesn't
1013	  have a local APIC, then the kernel will still run with no slowdown at
1014	  all. The local APIC supports CPU-generated self-interrupts (timer,
1015	  performance counters), and the NMI watchdog which detects hard
1016	  lockups.
1017
1018config X86_UP_IOAPIC
1019	bool "IO-APIC support on uniprocessors"
1020	depends on X86_UP_APIC
1021	---help---
1022	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1023	  SMP-capable replacement for PC-style interrupt controllers. Most
1024	  SMP systems and many recent uniprocessor systems have one.
1025
1026	  If you have a single-CPU system with an IO-APIC, you can say Y here
1027	  to use it. If you say Y here even though your machine doesn't have
1028	  an IO-APIC, then the kernel will still run with no slowdown at all.
1029
1030config X86_LOCAL_APIC
1031	def_bool y
1032	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1033	select IRQ_DOMAIN_HIERARCHY
1034	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
1035
1036config X86_IO_APIC
1037	def_bool y
1038	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1039
1040config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1041	bool "Reroute for broken boot IRQs"
1042	depends on X86_IO_APIC
1043	---help---
1044	  This option enables a workaround that fixes a source of
1045	  spurious interrupts. This is recommended when threaded
1046	  interrupt handling is used on systems where the generation of
1047	  superfluous "boot interrupts" cannot be disabled.
1048
1049	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1050	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
1051	  kernel does during interrupt handling). On chipsets where this
1052	  boot IRQ generation cannot be disabled, this workaround keeps
1053	  the original IRQ line masked so that only the equivalent "boot
1054	  IRQ" is delivered to the CPUs. The workaround also tells the
1055	  kernel to set up the IRQ handler on the boot IRQ line. In this
1056	  way only one interrupt is delivered to the kernel. Otherwise
1057	  the spurious second interrupt may cause the kernel to bring
1058	  down (vital) interrupt lines.
1059
1060	  Only affects "broken" chipsets. Interrupt sharing may be
1061	  increased on these systems.
1062
1063config X86_MCE
1064	bool "Machine Check / overheating reporting"
1065	select GENERIC_ALLOCATOR
1066	default y
1067	---help---
1068	  Machine Check support allows the processor to notify the
1069	  kernel if it detects a problem (e.g. overheating, data corruption).
1070	  The action the kernel takes depends on the severity of the problem,
1071	  ranging from warning messages to halting the machine.
1072
1073config X86_MCELOG_LEGACY
1074	bool "Support for deprecated /dev/mcelog character device"
1075	depends on X86_MCE
1076	---help---
1077	  Enable support for /dev/mcelog which is needed by the old mcelog
1078	  userspace logging daemon. Consider switching to the new generation
1079	  rasdaemon solution.
1080
1081config X86_MCE_INTEL
1082	def_bool y
1083	prompt "Intel MCE features"
1084	depends on X86_MCE && X86_LOCAL_APIC
1085	---help---
1086	   Additional support for intel specific MCE features such as
1087	   the thermal monitor.
1088
1089config X86_MCE_AMD
1090	def_bool y
1091	prompt "AMD MCE features"
1092	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
1093	---help---
1094	   Additional support for AMD specific MCE features such as
1095	   the DRAM Error Threshold.
1096
1097config X86_ANCIENT_MCE
1098	bool "Support for old Pentium 5 / WinChip machine checks"
1099	depends on X86_32 && X86_MCE
1100	---help---
1101	  Include support for machine check handling on old Pentium 5 or WinChip
1102	  systems. These typically need to be enabled explicitly on the command
1103	  line.
1104
1105config X86_MCE_THRESHOLD
1106	depends on X86_MCE_AMD || X86_MCE_INTEL
1107	def_bool y
1108
1109config X86_MCE_INJECT
1110	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
1111	tristate "Machine check injector support"
1112	---help---
1113	  Provide support for injecting machine checks for testing purposes.
1114	  If you don't know what a machine check is and you don't do kernel
1115	  QA it is safe to say n.
1116
1117config X86_THERMAL_VECTOR
1118	def_bool y
1119	depends on X86_MCE_INTEL
1120
1121source "arch/x86/events/Kconfig"
1122
1123config X86_LEGACY_VM86
1124	bool "Legacy VM86 support"
1125	default n
1126	depends on X86_32
1127	---help---
1128	  This option allows user programs to put the CPU into V8086
1129	  mode, which is an 80286-era approximation of 16-bit real mode.
1130
1131	  Some very old versions of X and/or vbetool require this option
1132	  for user mode setting.  Similarly, DOSEMU will use it if
1133	  available to accelerate real mode DOS programs.  However, any
1134	  recent version of DOSEMU, X, or vbetool should be fully
1135	  functional even without kernel VM86 support, as they will all
1136	  fall back to software emulation. Nevertheless, if you are using
1137	  a 16-bit DOS program where 16-bit performance matters, vm86
1138	  mode might be faster than emulation and you might want to
1139	  enable this option.
1140
1141	  Note that any app that works on a 64-bit kernel is unlikely to
1142	  need this option, as 64-bit kernels don't, and can't, support
1143	  V8086 mode. This option is also unrelated to 16-bit protected
1144	  mode and is not needed to run most 16-bit programs under Wine.
1145
1146	  Enabling this option increases the complexity of the kernel
1147	  and slows down exception handling a tiny bit.
1148
1149	  If unsure, say N here.
1150
1151config VM86
1152       bool
1153       default X86_LEGACY_VM86
1154
1155config X86_16BIT
1156	bool "Enable support for 16-bit segments" if EXPERT
1157	default y
1158	depends on MODIFY_LDT_SYSCALL
1159	---help---
1160	  This option is required by programs like Wine to run 16-bit
1161	  protected mode legacy code on x86 processors.  Disabling
1162	  this option saves about 300 bytes on i386, or around 6K text
1163	  plus 16K runtime memory on x86-64,
1164
1165config X86_ESPFIX32
1166	def_bool y
1167	depends on X86_16BIT && X86_32
1168
1169config X86_ESPFIX64
1170	def_bool y
1171	depends on X86_16BIT && X86_64
1172
1173config X86_VSYSCALL_EMULATION
1174       bool "Enable vsyscall emulation" if EXPERT
1175       default y
1176       depends on X86_64
1177       ---help---
1178	 This enables emulation of the legacy vsyscall page.  Disabling
1179	 it is roughly equivalent to booting with vsyscall=none, except
1180	 that it will also disable the helpful warning if a program
1181	 tries to use a vsyscall.  With this option set to N, offending
1182	 programs will just segfault, citing addresses of the form
1183	 0xffffffffff600?00.
1184
1185	 This option is required by many programs built before 2013, and
1186	 care should be used even with newer programs if set to N.
1187
1188	 Disabling this option saves about 7K of kernel size and
1189	 possibly 4K of additional runtime pagetable memory.
1190
1191config TOSHIBA
1192	tristate "Toshiba Laptop support"
1193	depends on X86_32
1194	---help---
1195	  This adds a driver to safely access the System Management Mode of
1196	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1197	  not work on models with a Phoenix BIOS. The System Management Mode
1198	  is used to set the BIOS and power saving options on Toshiba portables.
1199
1200	  For information on utilities to make use of this driver see the
1201	  Toshiba Linux utilities web site at:
1202	  <http://www.buzzard.org.uk/toshiba/>.
1203
1204	  Say Y if you intend to run this kernel on a Toshiba portable.
1205	  Say N otherwise.
1206
1207config I8K
1208	tristate "Dell i8k legacy laptop support"
1209	select HWMON
1210	select SENSORS_DELL_SMM
1211	---help---
1212	  This option enables legacy /proc/i8k userspace interface in hwmon
1213	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1214	  temperature and allows controlling fan speeds of Dell laptops via
1215	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1216	  it reports also power and hotkey status. For fan speed control is
1217	  needed userspace package i8kutils.
1218
1219	  Say Y if you intend to run this kernel on old Dell laptops or want to
1220	  use userspace package i8kutils.
1221	  Say N otherwise.
1222
1223config X86_REBOOTFIXUPS
1224	bool "Enable X86 board specific fixups for reboot"
1225	depends on X86_32
1226	---help---
1227	  This enables chipset and/or board specific fixups to be done
1228	  in order to get reboot to work correctly. This is only needed on
1229	  some combinations of hardware and BIOS. The symptom, for which
1230	  this config is intended, is when reboot ends with a stalled/hung
1231	  system.
1232
1233	  Currently, the only fixup is for the Geode machines using
1234	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1235
1236	  Say Y if you want to enable the fixup. Currently, it's safe to
1237	  enable this option even if you don't need it.
1238	  Say N otherwise.
1239
1240config MICROCODE
1241	bool "CPU microcode loading support"
1242	default y
1243	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1244	select FW_LOADER
1245	---help---
1246	  If you say Y here, you will be able to update the microcode on
1247	  Intel and AMD processors. The Intel support is for the IA32 family,
1248	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1249	  AMD support is for families 0x10 and later. You will obviously need
1250	  the actual microcode binary data itself which is not shipped with
1251	  the Linux kernel.
1252
1253	  The preferred method to load microcode from a detached initrd is described
1254	  in Documentation/x86/early-microcode.txt. For that you need to enable
1255	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1256	  initrd for microcode blobs.
1257
1258	  In addition, you can build-in the microcode into the kernel. For that you
1259	  need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
1260	  to the CONFIG_EXTRA_FIRMWARE config option.
1261
1262config MICROCODE_INTEL
1263	bool "Intel microcode loading support"
1264	depends on MICROCODE
1265	default MICROCODE
1266	select FW_LOADER
1267	---help---
1268	  This options enables microcode patch loading support for Intel
1269	  processors.
1270
1271	  For the current Intel microcode data package go to
1272	  <https://downloadcenter.intel.com> and search for
1273	  'Linux Processor Microcode Data File'.
1274
1275config MICROCODE_AMD
1276	bool "AMD microcode loading support"
1277	depends on MICROCODE
1278	select FW_LOADER
1279	---help---
1280	  If you select this option, microcode patch loading support for AMD
1281	  processors will be enabled.
1282
1283config MICROCODE_OLD_INTERFACE
1284	def_bool y
1285	depends on MICROCODE
1286
1287config X86_MSR
1288	tristate "/dev/cpu/*/msr - Model-specific register support"
1289	---help---
1290	  This device gives privileged processes access to the x86
1291	  Model-Specific Registers (MSRs).  It is a character device with
1292	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1293	  MSR accesses are directed to a specific CPU on multi-processor
1294	  systems.
1295
1296config X86_CPUID
1297	tristate "/dev/cpu/*/cpuid - CPU information support"
1298	---help---
1299	  This device gives processes access to the x86 CPUID instruction to
1300	  be executed on a specific processor.  It is a character device
1301	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1302	  /dev/cpu/31/cpuid.
1303
1304choice
1305	prompt "High Memory Support"
1306	default HIGHMEM4G
1307	depends on X86_32
1308
1309config NOHIGHMEM
1310	bool "off"
1311	---help---
1312	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1313	  However, the address space of 32-bit x86 processors is only 4
1314	  Gigabytes large. That means that, if you have a large amount of
1315	  physical memory, not all of it can be "permanently mapped" by the
1316	  kernel. The physical memory that's not permanently mapped is called
1317	  "high memory".
1318
1319	  If you are compiling a kernel which will never run on a machine with
1320	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1321	  choice and suitable for most users). This will result in a "3GB/1GB"
1322	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1323	  space and the remaining part of the 4GB virtual memory space is used
1324	  by the kernel to permanently map as much physical memory as
1325	  possible.
1326
1327	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1328	  answer "4GB" here.
1329
1330	  If more than 4 Gigabytes is used then answer "64GB" here. This
1331	  selection turns Intel PAE (Physical Address Extension) mode on.
1332	  PAE implements 3-level paging on IA32 processors. PAE is fully
1333	  supported by Linux, PAE mode is implemented on all recent Intel
1334	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1335	  then the kernel will not boot on CPUs that don't support PAE!
1336
1337	  The actual amount of total physical memory will either be
1338	  auto detected or can be forced by using a kernel command line option
1339	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1340	  your boot loader (lilo or loadlin) about how to pass options to the
1341	  kernel at boot time.)
1342
1343	  If unsure, say "off".
1344
1345config HIGHMEM4G
1346	bool "4GB"
1347	---help---
1348	  Select this if you have a 32-bit processor and between 1 and 4
1349	  gigabytes of physical RAM.
1350
1351config HIGHMEM64G
1352	bool "64GB"
1353	depends on !M486
1354	select X86_PAE
1355	---help---
1356	  Select this if you have a 32-bit processor and more than 4
1357	  gigabytes of physical RAM.
1358
1359endchoice
1360
1361choice
1362	prompt "Memory split" if EXPERT
1363	default VMSPLIT_3G
1364	depends on X86_32
1365	---help---
1366	  Select the desired split between kernel and user memory.
1367
1368	  If the address range available to the kernel is less than the
1369	  physical memory installed, the remaining memory will be available
1370	  as "high memory". Accessing high memory is a little more costly
1371	  than low memory, as it needs to be mapped into the kernel first.
1372	  Note that increasing the kernel address space limits the range
1373	  available to user programs, making the address space there
1374	  tighter.  Selecting anything other than the default 3G/1G split
1375	  will also likely make your kernel incompatible with binary-only
1376	  kernel modules.
1377
1378	  If you are not absolutely sure what you are doing, leave this
1379	  option alone!
1380
1381	config VMSPLIT_3G
1382		bool "3G/1G user/kernel split"
1383	config VMSPLIT_3G_OPT
1384		depends on !X86_PAE
1385		bool "3G/1G user/kernel split (for full 1G low memory)"
1386	config VMSPLIT_2G
1387		bool "2G/2G user/kernel split"
1388	config VMSPLIT_2G_OPT
1389		depends on !X86_PAE
1390		bool "2G/2G user/kernel split (for full 2G low memory)"
1391	config VMSPLIT_1G
1392		bool "1G/3G user/kernel split"
1393endchoice
1394
1395config PAGE_OFFSET
1396	hex
1397	default 0xB0000000 if VMSPLIT_3G_OPT
1398	default 0x80000000 if VMSPLIT_2G
1399	default 0x78000000 if VMSPLIT_2G_OPT
1400	default 0x40000000 if VMSPLIT_1G
1401	default 0xC0000000
1402	depends on X86_32
1403
1404config HIGHMEM
1405	def_bool y
1406	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1407
1408config X86_PAE
1409	bool "PAE (Physical Address Extension) Support"
1410	depends on X86_32 && !HIGHMEM4G
1411	select SWIOTLB
1412	---help---
1413	  PAE is required for NX support, and furthermore enables
1414	  larger swapspace support for non-overcommit purposes. It
1415	  has the cost of more pagetable lookup overhead, and also
1416	  consumes more pagetable space per process.
1417
1418config X86_5LEVEL
1419	bool "Enable 5-level page tables support"
1420	depends on X86_64
1421	---help---
1422	  5-level paging enables access to larger address space:
1423	  upto 128 PiB of virtual address space and 4 PiB of
1424	  physical address space.
1425
1426	  It will be supported by future Intel CPUs.
1427
1428	  Note: a kernel with this option enabled can only be booted
1429	  on machines that support the feature.
1430
1431	  See Documentation/x86/x86_64/5level-paging.txt for more
1432	  information.
1433
1434	  Say N if unsure.
1435
1436config ARCH_PHYS_ADDR_T_64BIT
1437	def_bool y
1438	depends on X86_64 || X86_PAE
1439
1440config ARCH_DMA_ADDR_T_64BIT
1441	def_bool y
1442	depends on X86_64 || HIGHMEM64G
1443
1444config X86_DIRECT_GBPAGES
1445	def_bool y
1446	depends on X86_64 && !DEBUG_PAGEALLOC
1447	---help---
1448	  Certain kernel features effectively disable kernel
1449	  linear 1 GB mappings (even if the CPU otherwise
1450	  supports them), so don't confuse the user by printing
1451	  that we have them enabled.
1452
1453config ARCH_HAS_MEM_ENCRYPT
1454	def_bool y
1455
1456config AMD_MEM_ENCRYPT
1457	bool "AMD Secure Memory Encryption (SME) support"
1458	depends on X86_64 && CPU_SUP_AMD
1459	---help---
1460	  Say yes to enable support for the encryption of system memory.
1461	  This requires an AMD processor that supports Secure Memory
1462	  Encryption (SME).
1463
1464config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1465	bool "Activate AMD Secure Memory Encryption (SME) by default"
1466	default y
1467	depends on AMD_MEM_ENCRYPT
1468	---help---
1469	  Say yes to have system memory encrypted by default if running on
1470	  an AMD processor that supports Secure Memory Encryption (SME).
1471
1472	  If set to Y, then the encryption of system memory can be
1473	  deactivated with the mem_encrypt=off command line option.
1474
1475	  If set to N, then the encryption of system memory can be
1476	  activated with the mem_encrypt=on command line option.
1477
1478config ARCH_USE_MEMREMAP_PROT
1479	def_bool y
1480	depends on AMD_MEM_ENCRYPT
1481
1482# Common NUMA Features
1483config NUMA
1484	bool "Numa Memory Allocation and Scheduler Support"
1485	depends on SMP
1486	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1487	default y if X86_BIGSMP
1488	---help---
1489	  Enable NUMA (Non Uniform Memory Access) support.
1490
1491	  The kernel will try to allocate memory used by a CPU on the
1492	  local memory controller of the CPU and add some more
1493	  NUMA awareness to the kernel.
1494
1495	  For 64-bit this is recommended if the system is Intel Core i7
1496	  (or later), AMD Opteron, or EM64T NUMA.
1497
1498	  For 32-bit this is only needed if you boot a 32-bit
1499	  kernel on a 64-bit NUMA platform.
1500
1501	  Otherwise, you should say N.
1502
1503config AMD_NUMA
1504	def_bool y
1505	prompt "Old style AMD Opteron NUMA detection"
1506	depends on X86_64 && NUMA && PCI
1507	---help---
1508	  Enable AMD NUMA node topology detection.  You should say Y here if
1509	  you have a multi processor AMD system. This uses an old method to
1510	  read the NUMA configuration directly from the builtin Northbridge
1511	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1512	  which also takes priority if both are compiled in.
1513
1514config X86_64_ACPI_NUMA
1515	def_bool y
1516	prompt "ACPI NUMA detection"
1517	depends on X86_64 && NUMA && ACPI && PCI
1518	select ACPI_NUMA
1519	---help---
1520	  Enable ACPI SRAT based node topology detection.
1521
1522# Some NUMA nodes have memory ranges that span
1523# other nodes.  Even though a pfn is valid and
1524# between a node's start and end pfns, it may not
1525# reside on that node.  See memmap_init_zone()
1526# for details.
1527config NODES_SPAN_OTHER_NODES
1528	def_bool y
1529	depends on X86_64_ACPI_NUMA
1530
1531config NUMA_EMU
1532	bool "NUMA emulation"
1533	depends on NUMA
1534	---help---
1535	  Enable NUMA emulation. A flat machine will be split
1536	  into virtual nodes when booted with "numa=fake=N", where N is the
1537	  number of nodes. This is only useful for debugging.
1538
1539config NODES_SHIFT
1540	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1541	range 1 10
1542	default "10" if MAXSMP
1543	default "6" if X86_64
1544	default "3"
1545	depends on NEED_MULTIPLE_NODES
1546	---help---
1547	  Specify the maximum number of NUMA Nodes available on the target
1548	  system.  Increases memory reserved to accommodate various tables.
1549
1550config ARCH_HAVE_MEMORY_PRESENT
1551	def_bool y
1552	depends on X86_32 && DISCONTIGMEM
1553
1554config NEED_NODE_MEMMAP_SIZE
1555	def_bool y
1556	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1557
1558config ARCH_FLATMEM_ENABLE
1559	def_bool y
1560	depends on X86_32 && !NUMA
1561
1562config ARCH_DISCONTIGMEM_ENABLE
1563	def_bool y
1564	depends on NUMA && X86_32
1565
1566config ARCH_DISCONTIGMEM_DEFAULT
1567	def_bool y
1568	depends on NUMA && X86_32
1569
1570config ARCH_SPARSEMEM_ENABLE
1571	def_bool y
1572	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1573	select SPARSEMEM_STATIC if X86_32
1574	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1575
1576config ARCH_SPARSEMEM_DEFAULT
1577	def_bool y
1578	depends on X86_64
1579
1580config ARCH_SELECT_MEMORY_MODEL
1581	def_bool y
1582	depends on ARCH_SPARSEMEM_ENABLE
1583
1584config ARCH_MEMORY_PROBE
1585	bool "Enable sysfs memory/probe interface"
1586	depends on X86_64 && MEMORY_HOTPLUG
1587	help
1588	  This option enables a sysfs memory/probe interface for testing.
1589	  See Documentation/memory-hotplug.txt for more information.
1590	  If you are unsure how to answer this question, answer N.
1591
1592config ARCH_PROC_KCORE_TEXT
1593	def_bool y
1594	depends on X86_64 && PROC_KCORE
1595
1596config ILLEGAL_POINTER_VALUE
1597       hex
1598       default 0 if X86_32
1599       default 0xdead000000000000 if X86_64
1600
1601source "mm/Kconfig"
1602
1603config X86_PMEM_LEGACY_DEVICE
1604	bool
1605
1606config X86_PMEM_LEGACY
1607	tristate "Support non-standard NVDIMMs and ADR protected memory"
1608	depends on PHYS_ADDR_T_64BIT
1609	depends on BLK_DEV
1610	select X86_PMEM_LEGACY_DEVICE
1611	select LIBNVDIMM
1612	help
1613	  Treat memory marked using the non-standard e820 type of 12 as used
1614	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1615	  The kernel will offer these regions to the 'pmem' driver so
1616	  they can be used for persistent storage.
1617
1618	  Say Y if unsure.
1619
1620config HIGHPTE
1621	bool "Allocate 3rd-level pagetables from highmem"
1622	depends on HIGHMEM
1623	---help---
1624	  The VM uses one page table entry for each page of physical memory.
1625	  For systems with a lot of RAM, this can be wasteful of precious
1626	  low memory.  Setting this option will put user-space page table
1627	  entries in high memory.
1628
1629config X86_CHECK_BIOS_CORRUPTION
1630	bool "Check for low memory corruption"
1631	---help---
1632	  Periodically check for memory corruption in low memory, which
1633	  is suspected to be caused by BIOS.  Even when enabled in the
1634	  configuration, it is disabled at runtime.  Enable it by
1635	  setting "memory_corruption_check=1" on the kernel command
1636	  line.  By default it scans the low 64k of memory every 60
1637	  seconds; see the memory_corruption_check_size and
1638	  memory_corruption_check_period parameters in
1639	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
1640
1641	  When enabled with the default parameters, this option has
1642	  almost no overhead, as it reserves a relatively small amount
1643	  of memory and scans it infrequently.  It both detects corruption
1644	  and prevents it from affecting the running system.
1645
1646	  It is, however, intended as a diagnostic tool; if repeatable
1647	  BIOS-originated corruption always affects the same memory,
1648	  you can use memmap= to prevent the kernel from using that
1649	  memory.
1650
1651config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1652	bool "Set the default setting of memory_corruption_check"
1653	depends on X86_CHECK_BIOS_CORRUPTION
1654	default y
1655	---help---
1656	  Set whether the default state of memory_corruption_check is
1657	  on or off.
1658
1659config X86_RESERVE_LOW
1660	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1661	default 64
1662	range 4 640
1663	---help---
1664	  Specify the amount of low memory to reserve for the BIOS.
1665
1666	  The first page contains BIOS data structures that the kernel
1667	  must not use, so that page must always be reserved.
1668
1669	  By default we reserve the first 64K of physical RAM, as a
1670	  number of BIOSes are known to corrupt that memory range
1671	  during events such as suspend/resume or monitor cable
1672	  insertion, so it must not be used by the kernel.
1673
1674	  You can set this to 4 if you are absolutely sure that you
1675	  trust the BIOS to get all its memory reservations and usages
1676	  right.  If you know your BIOS have problems beyond the
1677	  default 64K area, you can set this to 640 to avoid using the
1678	  entire low memory range.
1679
1680	  If you have doubts about the BIOS (e.g. suspend/resume does
1681	  not work or there's kernel crashes after certain hardware
1682	  hotplug events) then you might want to enable
1683	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1684	  typical corruption patterns.
1685
1686	  Leave this to the default value of 64 if you are unsure.
1687
1688config MATH_EMULATION
1689	bool
1690	depends on MODIFY_LDT_SYSCALL
1691	prompt "Math emulation" if X86_32
1692	---help---
1693	  Linux can emulate a math coprocessor (used for floating point
1694	  operations) if you don't have one. 486DX and Pentium processors have
1695	  a math coprocessor built in, 486SX and 386 do not, unless you added
1696	  a 487DX or 387, respectively. (The messages during boot time can
1697	  give you some hints here ["man dmesg"].) Everyone needs either a
1698	  coprocessor or this emulation.
1699
1700	  If you don't have a math coprocessor, you need to say Y here; if you
1701	  say Y here even though you have a coprocessor, the coprocessor will
1702	  be used nevertheless. (This behavior can be changed with the kernel
1703	  command line option "no387", which comes handy if your coprocessor
1704	  is broken. Try "man bootparam" or see the documentation of your boot
1705	  loader (lilo or loadlin) about how to pass options to the kernel at
1706	  boot time.) This means that it is a good idea to say Y here if you
1707	  intend to use this kernel on different machines.
1708
1709	  More information about the internals of the Linux math coprocessor
1710	  emulation can be found in <file:arch/x86/math-emu/README>.
1711
1712	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1713	  kernel, it won't hurt.
1714
1715config MTRR
1716	def_bool y
1717	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1718	---help---
1719	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1720	  the Memory Type Range Registers (MTRRs) may be used to control
1721	  processor access to memory ranges. This is most useful if you have
1722	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1723	  allows bus write transfers to be combined into a larger transfer
1724	  before bursting over the PCI/AGP bus. This can increase performance
1725	  of image write operations 2.5 times or more. Saying Y here creates a
1726	  /proc/mtrr file which may be used to manipulate your processor's
1727	  MTRRs. Typically the X server should use this.
1728
1729	  This code has a reasonably generic interface so that similar
1730	  control registers on other processors can be easily supported
1731	  as well:
1732
1733	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1734	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1735	  these, the ARRs are used to emulate the MTRRs.
1736	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1737	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1738	  write-combining. All of these processors are supported by this code
1739	  and it makes sense to say Y here if you have one of them.
1740
1741	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1742	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1743	  can lead to all sorts of problems, so it's good to say Y here.
1744
1745	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1746	  just add about 9 KB to your kernel.
1747
1748	  See <file:Documentation/x86/mtrr.txt> for more information.
1749
1750config MTRR_SANITIZER
1751	def_bool y
1752	prompt "MTRR cleanup support"
1753	depends on MTRR
1754	---help---
1755	  Convert MTRR layout from continuous to discrete, so X drivers can
1756	  add writeback entries.
1757
1758	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1759	  The largest mtrr entry size for a continuous block can be set with
1760	  mtrr_chunk_size.
1761
1762	  If unsure, say Y.
1763
1764config MTRR_SANITIZER_ENABLE_DEFAULT
1765	int "MTRR cleanup enable value (0-1)"
1766	range 0 1
1767	default "0"
1768	depends on MTRR_SANITIZER
1769	---help---
1770	  Enable mtrr cleanup default value
1771
1772config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1773	int "MTRR cleanup spare reg num (0-7)"
1774	range 0 7
1775	default "1"
1776	depends on MTRR_SANITIZER
1777	---help---
1778	  mtrr cleanup spare entries default, it can be changed via
1779	  mtrr_spare_reg_nr=N on the kernel command line.
1780
1781config X86_PAT
1782	def_bool y
1783	prompt "x86 PAT support" if EXPERT
1784	depends on MTRR
1785	---help---
1786	  Use PAT attributes to setup page level cache control.
1787
1788	  PATs are the modern equivalents of MTRRs and are much more
1789	  flexible than MTRRs.
1790
1791	  Say N here if you see bootup problems (boot crash, boot hang,
1792	  spontaneous reboots) or a non-working video driver.
1793
1794	  If unsure, say Y.
1795
1796config ARCH_USES_PG_UNCACHED
1797	def_bool y
1798	depends on X86_PAT
1799
1800config ARCH_RANDOM
1801	def_bool y
1802	prompt "x86 architectural random number generator" if EXPERT
1803	---help---
1804	  Enable the x86 architectural RDRAND instruction
1805	  (Intel Bull Mountain technology) to generate random numbers.
1806	  If supported, this is a high bandwidth, cryptographically
1807	  secure hardware random number generator.
1808
1809config X86_SMAP
1810	def_bool y
1811	prompt "Supervisor Mode Access Prevention" if EXPERT
1812	---help---
1813	  Supervisor Mode Access Prevention (SMAP) is a security
1814	  feature in newer Intel processors.  There is a small
1815	  performance cost if this enabled and turned on; there is
1816	  also a small increase in the kernel size if this is enabled.
1817
1818	  If unsure, say Y.
1819
1820config X86_INTEL_UMIP
1821	def_bool y
1822	depends on CPU_SUP_INTEL
1823	prompt "Intel User Mode Instruction Prevention" if EXPERT
1824	---help---
1825	  The User Mode Instruction Prevention (UMIP) is a security
1826	  feature in newer Intel processors. If enabled, a general
1827	  protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1828	  or STR instructions are executed in user mode. These instructions
1829	  unnecessarily expose information about the hardware state.
1830
1831	  The vast majority of applications do not use these instructions.
1832	  For the very few that do, software emulation is provided in
1833	  specific cases in protected and virtual-8086 modes. Emulated
1834	  results are dummy.
1835
1836config X86_INTEL_MPX
1837	prompt "Intel MPX (Memory Protection Extensions)"
1838	def_bool n
1839	# Note: only available in 64-bit mode due to VMA flags shortage
1840	depends on CPU_SUP_INTEL && X86_64
1841	select ARCH_USES_HIGH_VMA_FLAGS
1842	---help---
1843	  MPX provides hardware features that can be used in
1844	  conjunction with compiler-instrumented code to check
1845	  memory references.  It is designed to detect buffer
1846	  overflow or underflow bugs.
1847
1848	  This option enables running applications which are
1849	  instrumented or otherwise use MPX.  It does not use MPX
1850	  itself inside the kernel or to protect the kernel
1851	  against bad memory references.
1852
1853	  Enabling this option will make the kernel larger:
1854	  ~8k of kernel text and 36 bytes of data on a 64-bit
1855	  defconfig.  It adds a long to the 'mm_struct' which
1856	  will increase the kernel memory overhead of each
1857	  process and adds some branches to paths used during
1858	  exec() and munmap().
1859
1860	  For details, see Documentation/x86/intel_mpx.txt
1861
1862	  If unsure, say N.
1863
1864config X86_INTEL_MEMORY_PROTECTION_KEYS
1865	prompt "Intel Memory Protection Keys"
1866	def_bool y
1867	# Note: only available in 64-bit mode
1868	depends on CPU_SUP_INTEL && X86_64
1869	select ARCH_USES_HIGH_VMA_FLAGS
1870	select ARCH_HAS_PKEYS
1871	---help---
1872	  Memory Protection Keys provides a mechanism for enforcing
1873	  page-based protections, but without requiring modification of the
1874	  page tables when an application changes protection domains.
1875
1876	  For details, see Documentation/x86/protection-keys.txt
1877
1878	  If unsure, say y.
1879
1880config EFI
1881	bool "EFI runtime service support"
1882	depends on ACPI
1883	select UCS2_STRING
1884	select EFI_RUNTIME_WRAPPERS
1885	---help---
1886	  This enables the kernel to use EFI runtime services that are
1887	  available (such as the EFI variable services).
1888
1889	  This option is only useful on systems that have EFI firmware.
1890	  In addition, you should use the latest ELILO loader available
1891	  at <http://elilo.sourceforge.net> in order to take advantage
1892	  of EFI runtime services. However, even with this option, the
1893	  resultant kernel should continue to boot on existing non-EFI
1894	  platforms.
1895
1896config EFI_STUB
1897       bool "EFI stub support"
1898       depends on EFI && !X86_USE_3DNOW
1899       select RELOCATABLE
1900       ---help---
1901          This kernel feature allows a bzImage to be loaded directly
1902	  by EFI firmware without the use of a bootloader.
1903
1904	  See Documentation/efi-stub.txt for more information.
1905
1906config EFI_MIXED
1907	bool "EFI mixed-mode support"
1908	depends on EFI_STUB && X86_64
1909	---help---
1910	   Enabling this feature allows a 64-bit kernel to be booted
1911	   on a 32-bit firmware, provided that your CPU supports 64-bit
1912	   mode.
1913
1914	   Note that it is not possible to boot a mixed-mode enabled
1915	   kernel via the EFI boot stub - a bootloader that supports
1916	   the EFI handover protocol must be used.
1917
1918	   If unsure, say N.
1919
1920config SECCOMP
1921	def_bool y
1922	prompt "Enable seccomp to safely compute untrusted bytecode"
1923	---help---
1924	  This kernel feature is useful for number crunching applications
1925	  that may need to compute untrusted bytecode during their
1926	  execution. By using pipes or other transports made available to
1927	  the process as file descriptors supporting the read/write
1928	  syscalls, it's possible to isolate those applications in
1929	  their own address space using seccomp. Once seccomp is
1930	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1931	  and the task is only allowed to execute a few safe syscalls
1932	  defined by each seccomp mode.
1933
1934	  If unsure, say Y. Only embedded should say N here.
1935
1936source kernel/Kconfig.hz
1937
1938config KEXEC
1939	bool "kexec system call"
1940	select KEXEC_CORE
1941	---help---
1942	  kexec is a system call that implements the ability to shutdown your
1943	  current kernel, and to start another kernel.  It is like a reboot
1944	  but it is independent of the system firmware.   And like a reboot
1945	  you can start any kernel with it, not just Linux.
1946
1947	  The name comes from the similarity to the exec system call.
1948
1949	  It is an ongoing process to be certain the hardware in a machine
1950	  is properly shutdown, so do not be surprised if this code does not
1951	  initially work for you.  As of this writing the exact hardware
1952	  interface is strongly in flux, so no good recommendation can be
1953	  made.
1954
1955config KEXEC_FILE
1956	bool "kexec file based system call"
1957	select KEXEC_CORE
1958	select BUILD_BIN2C
1959	depends on X86_64
1960	depends on CRYPTO=y
1961	depends on CRYPTO_SHA256=y
1962	---help---
1963	  This is new version of kexec system call. This system call is
1964	  file based and takes file descriptors as system call argument
1965	  for kernel and initramfs as opposed to list of segments as
1966	  accepted by previous system call.
1967
1968config KEXEC_VERIFY_SIG
1969	bool "Verify kernel signature during kexec_file_load() syscall"
1970	depends on KEXEC_FILE
1971	---help---
1972	  This option makes kernel signature verification mandatory for
1973	  the kexec_file_load() syscall.
1974
1975	  In addition to that option, you need to enable signature
1976	  verification for the corresponding kernel image type being
1977	  loaded in order for this to work.
1978
1979config KEXEC_BZIMAGE_VERIFY_SIG
1980	bool "Enable bzImage signature verification support"
1981	depends on KEXEC_VERIFY_SIG
1982	depends on SIGNED_PE_FILE_VERIFICATION
1983	select SYSTEM_TRUSTED_KEYRING
1984	---help---
1985	  Enable bzImage signature verification support.
1986
1987config CRASH_DUMP
1988	bool "kernel crash dumps"
1989	depends on X86_64 || (X86_32 && HIGHMEM)
1990	---help---
1991	  Generate crash dump after being started by kexec.
1992	  This should be normally only set in special crash dump kernels
1993	  which are loaded in the main kernel with kexec-tools into
1994	  a specially reserved region and then later executed after
1995	  a crash by kdump/kexec. The crash dump kernel must be compiled
1996	  to a memory address not used by the main kernel or BIOS using
1997	  PHYSICAL_START, or it must be built as a relocatable image
1998	  (CONFIG_RELOCATABLE=y).
1999	  For more details see Documentation/kdump/kdump.txt
2000
2001config KEXEC_JUMP
2002	bool "kexec jump"
2003	depends on KEXEC && HIBERNATION
2004	---help---
2005	  Jump between original kernel and kexeced kernel and invoke
2006	  code in physical address mode via KEXEC
2007
2008config PHYSICAL_START
2009	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
2010	default "0x1000000"
2011	---help---
2012	  This gives the physical address where the kernel is loaded.
2013
2014	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2015	  bzImage will decompress itself to above physical address and
2016	  run from there. Otherwise, bzImage will run from the address where
2017	  it has been loaded by the boot loader and will ignore above physical
2018	  address.
2019
2020	  In normal kdump cases one does not have to set/change this option
2021	  as now bzImage can be compiled as a completely relocatable image
2022	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2023	  address. This option is mainly useful for the folks who don't want
2024	  to use a bzImage for capturing the crash dump and want to use a
2025	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
2026	  to be specifically compiled to run from a specific memory area
2027	  (normally a reserved region) and this option comes handy.
2028
2029	  So if you are using bzImage for capturing the crash dump,
2030	  leave the value here unchanged to 0x1000000 and set
2031	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
2032	  for capturing the crash dump change this value to start of
2033	  the reserved region.  In other words, it can be set based on
2034	  the "X" value as specified in the "crashkernel=YM@XM"
2035	  command line boot parameter passed to the panic-ed
2036	  kernel. Please take a look at Documentation/kdump/kdump.txt
2037	  for more details about crash dumps.
2038
2039	  Usage of bzImage for capturing the crash dump is recommended as
2040	  one does not have to build two kernels. Same kernel can be used
2041	  as production kernel and capture kernel. Above option should have
2042	  gone away after relocatable bzImage support is introduced. But it
2043	  is present because there are users out there who continue to use
2044	  vmlinux for dump capture. This option should go away down the
2045	  line.
2046
2047	  Don't change this unless you know what you are doing.
2048
2049config RELOCATABLE
2050	bool "Build a relocatable kernel"
2051	default y
2052	---help---
2053	  This builds a kernel image that retains relocation information
2054	  so it can be loaded someplace besides the default 1MB.
2055	  The relocations tend to make the kernel binary about 10% larger,
2056	  but are discarded at runtime.
2057
2058	  One use is for the kexec on panic case where the recovery kernel
2059	  must live at a different physical address than the primary
2060	  kernel.
2061
2062	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2063	  it has been loaded at and the compile time physical address
2064	  (CONFIG_PHYSICAL_START) is used as the minimum location.
2065
2066config RANDOMIZE_BASE
2067	bool "Randomize the address of the kernel image (KASLR)"
2068	depends on RELOCATABLE
2069	default y
2070	---help---
2071	  In support of Kernel Address Space Layout Randomization (KASLR),
2072	  this randomizes the physical address at which the kernel image
2073	  is decompressed and the virtual address where the kernel
2074	  image is mapped, as a security feature that deters exploit
2075	  attempts relying on knowledge of the location of kernel
2076	  code internals.
2077
2078	  On 64-bit, the kernel physical and virtual addresses are
2079	  randomized separately. The physical address will be anywhere
2080	  between 16MB and the top of physical memory (up to 64TB). The
2081	  virtual address will be randomized from 16MB up to 1GB (9 bits
2082	  of entropy). Note that this also reduces the memory space
2083	  available to kernel modules from 1.5GB to 1GB.
2084
2085	  On 32-bit, the kernel physical and virtual addresses are
2086	  randomized together. They will be randomized from 16MB up to
2087	  512MB (8 bits of entropy).
2088
2089	  Entropy is generated using the RDRAND instruction if it is
2090	  supported. If RDTSC is supported, its value is mixed into
2091	  the entropy pool as well. If neither RDRAND nor RDTSC are
2092	  supported, then entropy is read from the i8254 timer. The
2093	  usable entropy is limited by the kernel being built using
2094	  2GB addressing, and that PHYSICAL_ALIGN must be at a
2095	  minimum of 2MB. As a result, only 10 bits of entropy are
2096	  theoretically possible, but the implementations are further
2097	  limited due to memory layouts.
2098
2099	  If unsure, say Y.
2100
2101# Relocation on x86 needs some additional build support
2102config X86_NEED_RELOCS
2103	def_bool y
2104	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2105
2106config PHYSICAL_ALIGN
2107	hex "Alignment value to which kernel should be aligned"
2108	default "0x200000"
2109	range 0x2000 0x1000000 if X86_32
2110	range 0x200000 0x1000000 if X86_64
2111	---help---
2112	  This value puts the alignment restrictions on physical address
2113	  where kernel is loaded and run from. Kernel is compiled for an
2114	  address which meets above alignment restriction.
2115
2116	  If bootloader loads the kernel at a non-aligned address and
2117	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2118	  address aligned to above value and run from there.
2119
2120	  If bootloader loads the kernel at a non-aligned address and
2121	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2122	  load address and decompress itself to the address it has been
2123	  compiled for and run from there. The address for which kernel is
2124	  compiled already meets above alignment restrictions. Hence the
2125	  end result is that kernel runs from a physical address meeting
2126	  above alignment restrictions.
2127
2128	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2129	  this value must be a multiple of 0x200000.
2130
2131	  Don't change this unless you know what you are doing.
2132
2133config RANDOMIZE_MEMORY
2134	bool "Randomize the kernel memory sections"
2135	depends on X86_64
2136	depends on RANDOMIZE_BASE
2137	default RANDOMIZE_BASE
2138	---help---
2139	   Randomizes the base virtual address of kernel memory sections
2140	   (physical memory mapping, vmalloc & vmemmap). This security feature
2141	   makes exploits relying on predictable memory locations less reliable.
2142
2143	   The order of allocations remains unchanged. Entropy is generated in
2144	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
2145	   configuration have in average 30,000 different possible virtual
2146	   addresses for each memory section.
2147
2148	   If unsure, say Y.
2149
2150config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2151	hex "Physical memory mapping padding" if EXPERT
2152	depends on RANDOMIZE_MEMORY
2153	default "0xa" if MEMORY_HOTPLUG
2154	default "0x0"
2155	range 0x1 0x40 if MEMORY_HOTPLUG
2156	range 0x0 0x40
2157	---help---
2158	   Define the padding in terabytes added to the existing physical
2159	   memory size during kernel memory randomization. It is useful
2160	   for memory hotplug support but reduces the entropy available for
2161	   address randomization.
2162
2163	   If unsure, leave at the default value.
2164
2165config HOTPLUG_CPU
2166	bool "Support for hot-pluggable CPUs"
2167	depends on SMP
2168	---help---
2169	  Say Y here to allow turning CPUs off and on. CPUs can be
2170	  controlled through /sys/devices/system/cpu.
2171	  ( Note: power management support will enable this option
2172	    automatically on SMP systems. )
2173	  Say N if you want to disable CPU hotplug.
2174
2175config BOOTPARAM_HOTPLUG_CPU0
2176	bool "Set default setting of cpu0_hotpluggable"
2177	default n
2178	depends on HOTPLUG_CPU
2179	---help---
2180	  Set whether default state of cpu0_hotpluggable is on or off.
2181
2182	  Say Y here to enable CPU0 hotplug by default. If this switch
2183	  is turned on, there is no need to give cpu0_hotplug kernel
2184	  parameter and the CPU0 hotplug feature is enabled by default.
2185
2186	  Please note: there are two known CPU0 dependencies if you want
2187	  to enable the CPU0 hotplug feature either by this switch or by
2188	  cpu0_hotplug kernel parameter.
2189
2190	  First, resume from hibernate or suspend always starts from CPU0.
2191	  So hibernate and suspend are prevented if CPU0 is offline.
2192
2193	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2194	  offline if any interrupt can not migrate out of CPU0. There may
2195	  be other CPU0 dependencies.
2196
2197	  Please make sure the dependencies are under your control before
2198	  you enable this feature.
2199
2200	  Say N if you don't want to enable CPU0 hotplug feature by default.
2201	  You still can enable the CPU0 hotplug feature at boot by kernel
2202	  parameter cpu0_hotplug.
2203
2204config DEBUG_HOTPLUG_CPU0
2205	def_bool n
2206	prompt "Debug CPU0 hotplug"
2207	depends on HOTPLUG_CPU
2208	---help---
2209	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2210	  soon as possible and boots up userspace with CPU0 offlined. User
2211	  can online CPU0 back after boot time.
2212
2213	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2214	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2215	  compilation or giving cpu0_hotplug kernel parameter at boot.
2216
2217	  If unsure, say N.
2218
2219config COMPAT_VDSO
2220	def_bool n
2221	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2222	depends on COMPAT_32
2223	---help---
2224	  Certain buggy versions of glibc will crash if they are
2225	  presented with a 32-bit vDSO that is not mapped at the address
2226	  indicated in its segment table.
2227
2228	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2229	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2230	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2231	  the only released version with the bug, but OpenSUSE 9
2232	  contains a buggy "glibc 2.3.2".
2233
2234	  The symptom of the bug is that everything crashes on startup, saying:
2235	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2236
2237	  Saying Y here changes the default value of the vdso32 boot
2238	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2239	  This works around the glibc bug but hurts performance.
2240
2241	  If unsure, say N: if you are compiling your own kernel, you
2242	  are unlikely to be using a buggy version of glibc.
2243
2244choice
2245	prompt "vsyscall table for legacy applications"
2246	depends on X86_64
2247	default LEGACY_VSYSCALL_EMULATE
2248	help
2249	  Legacy user code that does not know how to find the vDSO expects
2250	  to be able to issue three syscalls by calling fixed addresses in
2251	  kernel space. Since this location is not randomized with ASLR,
2252	  it can be used to assist security vulnerability exploitation.
2253
2254	  This setting can be changed at boot time via the kernel command
2255	  line parameter vsyscall=[native|emulate|none].
2256
2257	  On a system with recent enough glibc (2.14 or newer) and no
2258	  static binaries, you can say None without a performance penalty
2259	  to improve security.
2260
2261	  If unsure, select "Emulate".
2262
2263	config LEGACY_VSYSCALL_NATIVE
2264		bool "Native"
2265		help
2266		  Actual executable code is located in the fixed vsyscall
2267		  address mapping, implementing time() efficiently. Since
2268		  this makes the mapping executable, it can be used during
2269		  security vulnerability exploitation (traditionally as
2270		  ROP gadgets). This configuration is not recommended.
2271
2272	config LEGACY_VSYSCALL_EMULATE
2273		bool "Emulate"
2274		help
2275		  The kernel traps and emulates calls into the fixed
2276		  vsyscall address mapping. This makes the mapping
2277		  non-executable, but it still contains known contents,
2278		  which could be used in certain rare security vulnerability
2279		  exploits. This configuration is recommended when userspace
2280		  still uses the vsyscall area.
2281
2282	config LEGACY_VSYSCALL_NONE
2283		bool "None"
2284		help
2285		  There will be no vsyscall mapping at all. This will
2286		  eliminate any risk of ASLR bypass due to the vsyscall
2287		  fixed address mapping. Attempts to use the vsyscalls
2288		  will be reported to dmesg, so that either old or
2289		  malicious userspace programs can be identified.
2290
2291endchoice
2292
2293config CMDLINE_BOOL
2294	bool "Built-in kernel command line"
2295	---help---
2296	  Allow for specifying boot arguments to the kernel at
2297	  build time.  On some systems (e.g. embedded ones), it is
2298	  necessary or convenient to provide some or all of the
2299	  kernel boot arguments with the kernel itself (that is,
2300	  to not rely on the boot loader to provide them.)
2301
2302	  To compile command line arguments into the kernel,
2303	  set this option to 'Y', then fill in the
2304	  boot arguments in CONFIG_CMDLINE.
2305
2306	  Systems with fully functional boot loaders (i.e. non-embedded)
2307	  should leave this option set to 'N'.
2308
2309config CMDLINE
2310	string "Built-in kernel command string"
2311	depends on CMDLINE_BOOL
2312	default ""
2313	---help---
2314	  Enter arguments here that should be compiled into the kernel
2315	  image and used at boot time.  If the boot loader provides a
2316	  command line at boot time, it is appended to this string to
2317	  form the full kernel command line, when the system boots.
2318
2319	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2320	  change this behavior.
2321
2322	  In most cases, the command line (whether built-in or provided
2323	  by the boot loader) should specify the device for the root
2324	  file system.
2325
2326config CMDLINE_OVERRIDE
2327	bool "Built-in command line overrides boot loader arguments"
2328	depends on CMDLINE_BOOL
2329	---help---
2330	  Set this option to 'Y' to have the kernel ignore the boot loader
2331	  command line, and use ONLY the built-in command line.
2332
2333	  This is used to work around broken boot loaders.  This should
2334	  be set to 'N' under normal conditions.
2335
2336config MODIFY_LDT_SYSCALL
2337	bool "Enable the LDT (local descriptor table)" if EXPERT
2338	default y
2339	---help---
2340	  Linux can allow user programs to install a per-process x86
2341	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2342	  call.  This is required to run 16-bit or segmented code such as
2343	  DOSEMU or some Wine programs.  It is also used by some very old
2344	  threading libraries.
2345
2346	  Enabling this feature adds a small amount of overhead to
2347	  context switches and increases the low-level kernel attack
2348	  surface.  Disabling it removes the modify_ldt(2) system call.
2349
2350	  Saying 'N' here may make sense for embedded or server kernels.
2351
2352source "kernel/livepatch/Kconfig"
2353
2354endmenu
2355
2356config ARCH_HAS_ADD_PAGES
2357	def_bool y
2358	depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2359
2360config ARCH_ENABLE_MEMORY_HOTPLUG
2361	def_bool y
2362	depends on X86_64 || (X86_32 && HIGHMEM)
2363
2364config ARCH_ENABLE_MEMORY_HOTREMOVE
2365	def_bool y
2366	depends on MEMORY_HOTPLUG
2367
2368config USE_PERCPU_NUMA_NODE_ID
2369	def_bool y
2370	depends on NUMA
2371
2372config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2373	def_bool y
2374	depends on X86_64 || X86_PAE
2375
2376config ARCH_ENABLE_HUGEPAGE_MIGRATION
2377	def_bool y
2378	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2379
2380config ARCH_ENABLE_THP_MIGRATION
2381	def_bool y
2382	depends on X86_64 && TRANSPARENT_HUGEPAGE
2383
2384menu "Power management and ACPI options"
2385
2386config ARCH_HIBERNATION_HEADER
2387	def_bool y
2388	depends on X86_64 && HIBERNATION
2389
2390source "kernel/power/Kconfig"
2391
2392source "drivers/acpi/Kconfig"
2393
2394source "drivers/sfi/Kconfig"
2395
2396config X86_APM_BOOT
2397	def_bool y
2398	depends on APM
2399
2400menuconfig APM
2401	tristate "APM (Advanced Power Management) BIOS support"
2402	depends on X86_32 && PM_SLEEP
2403	---help---
2404	  APM is a BIOS specification for saving power using several different
2405	  techniques. This is mostly useful for battery powered laptops with
2406	  APM compliant BIOSes. If you say Y here, the system time will be
2407	  reset after a RESUME operation, the /proc/apm device will provide
2408	  battery status information, and user-space programs will receive
2409	  notification of APM "events" (e.g. battery status change).
2410
2411	  If you select "Y" here, you can disable actual use of the APM
2412	  BIOS by passing the "apm=off" option to the kernel at boot time.
2413
2414	  Note that the APM support is almost completely disabled for
2415	  machines with more than one CPU.
2416
2417	  In order to use APM, you will need supporting software. For location
2418	  and more information, read <file:Documentation/power/apm-acpi.txt>
2419	  and the Battery Powered Linux mini-HOWTO, available from
2420	  <http://www.tldp.org/docs.html#howto>.
2421
2422	  This driver does not spin down disk drives (see the hdparm(8)
2423	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2424	  VESA-compliant "green" monitors.
2425
2426	  This driver does not support the TI 4000M TravelMate and the ACER
2427	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2428	  desktop machines also don't have compliant BIOSes, and this driver
2429	  may cause those machines to panic during the boot phase.
2430
2431	  Generally, if you don't have a battery in your machine, there isn't
2432	  much point in using this driver and you should say N. If you get
2433	  random kernel OOPSes or reboots that don't seem to be related to
2434	  anything, try disabling/enabling this option (or disabling/enabling
2435	  APM in your BIOS).
2436
2437	  Some other things you should try when experiencing seemingly random,
2438	  "weird" problems:
2439
2440	  1) make sure that you have enough swap space and that it is
2441	  enabled.
2442	  2) pass the "no-hlt" option to the kernel
2443	  3) switch on floating point emulation in the kernel and pass
2444	  the "no387" option to the kernel
2445	  4) pass the "floppy=nodma" option to the kernel
2446	  5) pass the "mem=4M" option to the kernel (thereby disabling
2447	  all but the first 4 MB of RAM)
2448	  6) make sure that the CPU is not over clocked.
2449	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2450	  8) disable the cache from your BIOS settings
2451	  9) install a fan for the video card or exchange video RAM
2452	  10) install a better fan for the CPU
2453	  11) exchange RAM chips
2454	  12) exchange the motherboard.
2455
2456	  To compile this driver as a module, choose M here: the
2457	  module will be called apm.
2458
2459if APM
2460
2461config APM_IGNORE_USER_SUSPEND
2462	bool "Ignore USER SUSPEND"
2463	---help---
2464	  This option will ignore USER SUSPEND requests. On machines with a
2465	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2466	  series notebooks, it is necessary to say Y because of a BIOS bug.
2467
2468config APM_DO_ENABLE
2469	bool "Enable PM at boot time"
2470	---help---
2471	  Enable APM features at boot time. From page 36 of the APM BIOS
2472	  specification: "When disabled, the APM BIOS does not automatically
2473	  power manage devices, enter the Standby State, enter the Suspend
2474	  State, or take power saving steps in response to CPU Idle calls."
2475	  This driver will make CPU Idle calls when Linux is idle (unless this
2476	  feature is turned off -- see "Do CPU IDLE calls", below). This
2477	  should always save battery power, but more complicated APM features
2478	  will be dependent on your BIOS implementation. You may need to turn
2479	  this option off if your computer hangs at boot time when using APM
2480	  support, or if it beeps continuously instead of suspending. Turn
2481	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2482	  T400CDT. This is off by default since most machines do fine without
2483	  this feature.
2484
2485config APM_CPU_IDLE
2486	depends on CPU_IDLE
2487	bool "Make CPU Idle calls when idle"
2488	---help---
2489	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2490	  On some machines, this can activate improved power savings, such as
2491	  a slowed CPU clock rate, when the machine is idle. These idle calls
2492	  are made after the idle loop has run for some length of time (e.g.,
2493	  333 mS). On some machines, this will cause a hang at boot time or
2494	  whenever the CPU becomes idle. (On machines with more than one CPU,
2495	  this option does nothing.)
2496
2497config APM_DISPLAY_BLANK
2498	bool "Enable console blanking using APM"
2499	---help---
2500	  Enable console blanking using the APM. Some laptops can use this to
2501	  turn off the LCD backlight when the screen blanker of the Linux
2502	  virtual console blanks the screen. Note that this is only used by
2503	  the virtual console screen blanker, and won't turn off the backlight
2504	  when using the X Window system. This also doesn't have anything to
2505	  do with your VESA-compliant power-saving monitor. Further, this
2506	  option doesn't work for all laptops -- it might not turn off your
2507	  backlight at all, or it might print a lot of errors to the console,
2508	  especially if you are using gpm.
2509
2510config APM_ALLOW_INTS
2511	bool "Allow interrupts during APM BIOS calls"
2512	---help---
2513	  Normally we disable external interrupts while we are making calls to
2514	  the APM BIOS as a measure to lessen the effects of a badly behaving
2515	  BIOS implementation.  The BIOS should reenable interrupts if it
2516	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2517	  many of the newer IBM Thinkpads.  If you experience hangs when you
2518	  suspend, try setting this to Y.  Otherwise, say N.
2519
2520endif # APM
2521
2522source "drivers/cpufreq/Kconfig"
2523
2524source "drivers/cpuidle/Kconfig"
2525
2526source "drivers/idle/Kconfig"
2527
2528endmenu
2529
2530
2531menu "Bus options (PCI etc.)"
2532
2533config PCI
2534	bool "PCI support"
2535	default y
2536	---help---
2537	  Find out whether you have a PCI motherboard. PCI is the name of a
2538	  bus system, i.e. the way the CPU talks to the other stuff inside
2539	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2540	  VESA. If you have PCI, say Y, otherwise N.
2541
2542choice
2543	prompt "PCI access mode"
2544	depends on X86_32 && PCI
2545	default PCI_GOANY
2546	---help---
2547	  On PCI systems, the BIOS can be used to detect the PCI devices and
2548	  determine their configuration. However, some old PCI motherboards
2549	  have BIOS bugs and may crash if this is done. Also, some embedded
2550	  PCI-based systems don't have any BIOS at all. Linux can also try to
2551	  detect the PCI hardware directly without using the BIOS.
2552
2553	  With this option, you can specify how Linux should detect the
2554	  PCI devices. If you choose "BIOS", the BIOS will be used,
2555	  if you choose "Direct", the BIOS won't be used, and if you
2556	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2557	  If you choose "Any", the kernel will try MMCONFIG, then the
2558	  direct access method and falls back to the BIOS if that doesn't
2559	  work. If unsure, go with the default, which is "Any".
2560
2561config PCI_GOBIOS
2562	bool "BIOS"
2563
2564config PCI_GOMMCONFIG
2565	bool "MMConfig"
2566
2567config PCI_GODIRECT
2568	bool "Direct"
2569
2570config PCI_GOOLPC
2571	bool "OLPC XO-1"
2572	depends on OLPC
2573
2574config PCI_GOANY
2575	bool "Any"
2576
2577endchoice
2578
2579config PCI_BIOS
2580	def_bool y
2581	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2582
2583# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2584config PCI_DIRECT
2585	def_bool y
2586	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2587
2588config PCI_MMCONFIG
2589	def_bool y
2590	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2591
2592config PCI_OLPC
2593	def_bool y
2594	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2595
2596config PCI_XEN
2597	def_bool y
2598	depends on PCI && XEN
2599	select SWIOTLB_XEN
2600
2601config PCI_DOMAINS
2602	def_bool y
2603	depends on PCI
2604
2605config PCI_MMCONFIG
2606	bool "Support mmconfig PCI config space access"
2607	depends on X86_64 && PCI && ACPI
2608
2609config PCI_CNB20LE_QUIRK
2610	bool "Read CNB20LE Host Bridge Windows" if EXPERT
2611	depends on PCI
2612	help
2613	  Read the PCI windows out of the CNB20LE host bridge. This allows
2614	  PCI hotplug to work on systems with the CNB20LE chipset which do
2615	  not have ACPI.
2616
2617	  There's no public spec for this chipset, and this functionality
2618	  is known to be incomplete.
2619
2620	  You should say N unless you know you need this.
2621
2622source "drivers/pci/Kconfig"
2623
2624config ISA_BUS
2625	bool "ISA-style bus support on modern systems" if EXPERT
2626	select ISA_BUS_API
2627	help
2628	  Enables ISA-style drivers on modern systems. This is necessary to
2629	  support PC/104 devices on X86_64 platforms.
2630
2631	  If unsure, say N.
2632
2633# x86_64 have no ISA slots, but can have ISA-style DMA.
2634config ISA_DMA_API
2635	bool "ISA-style DMA support" if (X86_64 && EXPERT)
2636	default y
2637	help
2638	  Enables ISA-style DMA support for devices requiring such controllers.
2639	  If unsure, say Y.
2640
2641if X86_32
2642
2643config ISA
2644	bool "ISA support"
2645	---help---
2646	  Find out whether you have ISA slots on your motherboard.  ISA is the
2647	  name of a bus system, i.e. the way the CPU talks to the other stuff
2648	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2649	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2650	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2651
2652config EISA
2653	bool "EISA support"
2654	depends on ISA
2655	---help---
2656	  The Extended Industry Standard Architecture (EISA) bus was
2657	  developed as an open alternative to the IBM MicroChannel bus.
2658
2659	  The EISA bus provided some of the features of the IBM MicroChannel
2660	  bus while maintaining backward compatibility with cards made for
2661	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2662	  1995 when it was made obsolete by the PCI bus.
2663
2664	  Say Y here if you are building a kernel for an EISA-based machine.
2665
2666	  Otherwise, say N.
2667
2668source "drivers/eisa/Kconfig"
2669
2670config SCx200
2671	tristate "NatSemi SCx200 support"
2672	---help---
2673	  This provides basic support for National Semiconductor's
2674	  (now AMD's) Geode processors.  The driver probes for the
2675	  PCI-IDs of several on-chip devices, so its a good dependency
2676	  for other scx200_* drivers.
2677
2678	  If compiled as a module, the driver is named scx200.
2679
2680config SCx200HR_TIMER
2681	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2682	depends on SCx200
2683	default y
2684	---help---
2685	  This driver provides a clocksource built upon the on-chip
2686	  27MHz high-resolution timer.  Its also a workaround for
2687	  NSC Geode SC-1100's buggy TSC, which loses time when the
2688	  processor goes idle (as is done by the scheduler).  The
2689	  other workaround is idle=poll boot option.
2690
2691config OLPC
2692	bool "One Laptop Per Child support"
2693	depends on !X86_PAE
2694	select GPIOLIB
2695	select OF
2696	select OF_PROMTREE
2697	select IRQ_DOMAIN
2698	---help---
2699	  Add support for detecting the unique features of the OLPC
2700	  XO hardware.
2701
2702config OLPC_XO1_PM
2703	bool "OLPC XO-1 Power Management"
2704	depends on OLPC && MFD_CS5535 && PM_SLEEP
2705	select MFD_CORE
2706	---help---
2707	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2708
2709config OLPC_XO1_RTC
2710	bool "OLPC XO-1 Real Time Clock"
2711	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2712	---help---
2713	  Add support for the XO-1 real time clock, which can be used as a
2714	  programmable wakeup source.
2715
2716config OLPC_XO1_SCI
2717	bool "OLPC XO-1 SCI extras"
2718	depends on OLPC && OLPC_XO1_PM
2719	depends on INPUT=y
2720	select POWER_SUPPLY
2721	select GPIO_CS5535
2722	select MFD_CORE
2723	---help---
2724	  Add support for SCI-based features of the OLPC XO-1 laptop:
2725	   - EC-driven system wakeups
2726	   - Power button
2727	   - Ebook switch
2728	   - Lid switch
2729	   - AC adapter status updates
2730	   - Battery status updates
2731
2732config OLPC_XO15_SCI
2733	bool "OLPC XO-1.5 SCI extras"
2734	depends on OLPC && ACPI
2735	select POWER_SUPPLY
2736	---help---
2737	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2738	   - EC-driven system wakeups
2739	   - AC adapter status updates
2740	   - Battery status updates
2741
2742config ALIX
2743	bool "PCEngines ALIX System Support (LED setup)"
2744	select GPIOLIB
2745	---help---
2746	  This option enables system support for the PCEngines ALIX.
2747	  At present this just sets up LEDs for GPIO control on
2748	  ALIX2/3/6 boards.  However, other system specific setup should
2749	  get added here.
2750
2751	  Note: You must still enable the drivers for GPIO and LED support
2752	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2753
2754	  Note: You have to set alix.force=1 for boards with Award BIOS.
2755
2756config NET5501
2757	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2758	select GPIOLIB
2759	---help---
2760	  This option enables system support for the Soekris Engineering net5501.
2761
2762config GEOS
2763	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2764	select GPIOLIB
2765	depends on DMI
2766	---help---
2767	  This option enables system support for the Traverse Technologies GEOS.
2768
2769config TS5500
2770	bool "Technologic Systems TS-5500 platform support"
2771	depends on MELAN
2772	select CHECK_SIGNATURE
2773	select NEW_LEDS
2774	select LEDS_CLASS
2775	---help---
2776	  This option enables system support for the Technologic Systems TS-5500.
2777
2778endif # X86_32
2779
2780config AMD_NB
2781	def_bool y
2782	depends on CPU_SUP_AMD && PCI
2783
2784source "drivers/pcmcia/Kconfig"
2785
2786config RAPIDIO
2787	tristate "RapidIO support"
2788	depends on PCI
2789	default n
2790	help
2791	  If enabled this option will include drivers and the core
2792	  infrastructure code to support RapidIO interconnect devices.
2793
2794source "drivers/rapidio/Kconfig"
2795
2796config X86_SYSFB
2797	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2798	help
2799	  Firmwares often provide initial graphics framebuffers so the BIOS,
2800	  bootloader or kernel can show basic video-output during boot for
2801	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2802	  Extensions and EFI-framebuffers for this, which are mostly limited
2803	  to x86.
2804	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2805	  framebuffers so the new generic system-framebuffer drivers can be
2806	  used on x86. If the framebuffer is not compatible with the generic
2807	  modes, it is adverticed as fallback platform framebuffer so legacy
2808	  drivers like efifb, vesafb and uvesafb can pick it up.
2809	  If this option is not selected, all system framebuffers are always
2810	  marked as fallback platform framebuffers as usual.
2811
2812	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2813	  not be able to pick up generic system framebuffers if this option
2814	  is selected. You are highly encouraged to enable simplefb as
2815	  replacement if you select this option. simplefb can correctly deal
2816	  with generic system framebuffers. But you should still keep vesafb
2817	  and others enabled as fallback if a system framebuffer is
2818	  incompatible with simplefb.
2819
2820	  If unsure, say Y.
2821
2822endmenu
2823
2824
2825menu "Executable file formats / Emulations"
2826
2827source "fs/Kconfig.binfmt"
2828
2829config IA32_EMULATION
2830	bool "IA32 Emulation"
2831	depends on X86_64
2832	select ARCH_WANT_OLD_COMPAT_IPC
2833	select BINFMT_ELF
2834	select COMPAT_BINFMT_ELF
2835	select COMPAT_OLD_SIGACTION
2836	---help---
2837	  Include code to run legacy 32-bit programs under a
2838	  64-bit kernel. You should likely turn this on, unless you're
2839	  100% sure that you don't have any 32-bit programs left.
2840
2841config IA32_AOUT
2842	tristate "IA32 a.out support"
2843	depends on IA32_EMULATION
2844	---help---
2845	  Support old a.out binaries in the 32bit emulation.
2846
2847config X86_X32
2848	bool "x32 ABI for 64-bit mode"
2849	depends on X86_64
2850	---help---
2851	  Include code to run binaries for the x32 native 32-bit ABI
2852	  for 64-bit processors.  An x32 process gets access to the
2853	  full 64-bit register file and wide data path while leaving
2854	  pointers at 32 bits for smaller memory footprint.
2855
2856	  You will need a recent binutils (2.22 or later) with
2857	  elf32_x86_64 support enabled to compile a kernel with this
2858	  option set.
2859
2860config COMPAT_32
2861	def_bool y
2862	depends on IA32_EMULATION || X86_32
2863	select HAVE_UID16
2864	select OLD_SIGSUSPEND3
2865
2866config COMPAT
2867	def_bool y
2868	depends on IA32_EMULATION || X86_X32
2869
2870if COMPAT
2871config COMPAT_FOR_U64_ALIGNMENT
2872	def_bool y
2873
2874config SYSVIPC_COMPAT
2875	def_bool y
2876	depends on SYSVIPC
2877endif
2878
2879endmenu
2880
2881
2882config HAVE_ATOMIC_IOMAP
2883	def_bool y
2884	depends on X86_32
2885
2886config X86_DEV_DMA_OPS
2887	bool
2888	depends on X86_64 || STA2X11
2889
2890config X86_DMA_REMAP
2891	bool
2892	depends on STA2X11
2893
2894config HAVE_GENERIC_GUP
2895	def_bool y
2896
2897source "net/Kconfig"
2898
2899source "drivers/Kconfig"
2900
2901source "drivers/firmware/Kconfig"
2902
2903source "fs/Kconfig"
2904
2905source "arch/x86/Kconfig.debug"
2906
2907source "security/Kconfig"
2908
2909source "crypto/Kconfig"
2910
2911source "arch/x86/kvm/Kconfig"
2912
2913source "lib/Kconfig"
2914