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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_GENERIC_DMA_COHERENT
18	select MODULES_USE_ELF_REL
19	select OLD_SIGACTION
20
21config X86_64
22	def_bool y
23	depends on 64BIT
24	# Options that are inherently 64-bit kernel only:
25	select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
26	select ARCH_SUPPORTS_INT128
27	select ARCH_USE_CMPXCHG_LOCKREF
28	select HAVE_ARCH_SOFT_DIRTY
29	select MODULES_USE_ELF_RELA
30	select NEED_DMA_MAP_STATE
31	select SWIOTLB
32	select X86_DEV_DMA_OPS
33	select ARCH_HAS_SYSCALL_WRAPPER
34
35#
36# Arch settings
37#
38# ( Note that options that are marked 'if X86_64' could in principle be
39#   ported to 32-bit as well. )
40#
41config X86
42	def_bool y
43	#
44	# Note: keep this list sorted alphabetically
45	#
46	select ACPI_LEGACY_TABLES_LOOKUP	if ACPI
47	select ACPI_SYSTEM_POWER_STATES_SUPPORT	if ACPI
48	select ANON_INODES
49	select ARCH_CLOCKSOURCE_DATA
50	select ARCH_DISCARD_MEMBLOCK
51	select ARCH_HAS_ACPI_TABLE_UPGRADE	if ACPI
52	select ARCH_HAS_DEBUG_VIRTUAL
53	select ARCH_HAS_DEVMEM_IS_ALLOWED
54	select ARCH_HAS_ELF_RANDOMIZE
55	select ARCH_HAS_FAST_MULTIPLIER
56	select ARCH_HAS_FILTER_PGPROT
57	select ARCH_HAS_FORTIFY_SOURCE
58	select ARCH_HAS_GCOV_PROFILE_ALL
59	select ARCH_HAS_KCOV			if X86_64
60	select ARCH_HAS_MEMBARRIER_SYNC_CORE
61	select ARCH_HAS_PMEM_API		if X86_64
62	select ARCH_HAS_PTE_SPECIAL
63	select ARCH_HAS_REFCOUNT
64	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
65	select ARCH_HAS_UACCESS_MCSAFE		if X86_64 && X86_MCE
66	select ARCH_HAS_SET_MEMORY
67	select ARCH_HAS_SG_CHAIN
68	select ARCH_HAS_STRICT_KERNEL_RWX
69	select ARCH_HAS_STRICT_MODULE_RWX
70	select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
71	select ARCH_HAS_UBSAN_SANITIZE_ALL
72	select ARCH_HAS_ZONE_DEVICE		if X86_64
73	select ARCH_HAVE_NMI_SAFE_CMPXCHG
74	select ARCH_MIGHT_HAVE_ACPI_PDC		if ACPI
75	select ARCH_MIGHT_HAVE_PC_PARPORT
76	select ARCH_MIGHT_HAVE_PC_SERIO
77	select ARCH_SUPPORTS_ACPI
78	select ARCH_SUPPORTS_ATOMIC_RMW
79	select ARCH_SUPPORTS_NUMA_BALANCING	if X86_64
80	select ARCH_USE_BUILTIN_BSWAP
81	select ARCH_USE_QUEUED_RWLOCKS
82	select ARCH_USE_QUEUED_SPINLOCKS
83	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
84	select ARCH_WANTS_DYNAMIC_TASK_STRUCT
85	select ARCH_WANTS_THP_SWAP		if X86_64
86	select BUILDTIME_EXTABLE_SORT
87	select CLKEVT_I8253
88	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
89	select CLOCKSOURCE_WATCHDOG
90	select DCACHE_WORD_ACCESS
91	select DMA_DIRECT_OPS
92	select EDAC_ATOMIC_SCRUB
93	select EDAC_SUPPORT
94	select GENERIC_CLOCKEVENTS
95	select GENERIC_CLOCKEVENTS_BROADCAST	if X86_64 || (X86_32 && X86_LOCAL_APIC)
96	select GENERIC_CLOCKEVENTS_MIN_ADJUST
97	select GENERIC_CMOS_UPDATE
98	select GENERIC_CPU_AUTOPROBE
99	select GENERIC_CPU_VULNERABILITIES
100	select GENERIC_EARLY_IOREMAP
101	select GENERIC_FIND_FIRST_BIT
102	select GENERIC_IOMAP
103	select GENERIC_IRQ_EFFECTIVE_AFF_MASK	if SMP
104	select GENERIC_IRQ_MATRIX_ALLOCATOR	if X86_LOCAL_APIC
105	select GENERIC_IRQ_MIGRATION		if SMP
106	select GENERIC_IRQ_PROBE
107	select GENERIC_IRQ_RESERVATION_MODE
108	select GENERIC_IRQ_SHOW
109	select GENERIC_PENDING_IRQ		if SMP
110	select GENERIC_SMP_IDLE_THREAD
111	select GENERIC_STRNCPY_FROM_USER
112	select GENERIC_STRNLEN_USER
113	select GENERIC_TIME_VSYSCALL
114	select HARDLOCKUP_CHECK_TIMESTAMP	if X86_64
115	select HAVE_ACPI_APEI			if ACPI
116	select HAVE_ACPI_APEI_NMI		if ACPI
117	select HAVE_ALIGNED_STRUCT_PAGE		if SLUB
118	select HAVE_ARCH_AUDITSYSCALL
119	select HAVE_ARCH_HUGE_VMAP		if X86_64 || X86_PAE
120	select HAVE_ARCH_JUMP_LABEL
121	select HAVE_ARCH_KASAN			if X86_64
122	select HAVE_ARCH_KGDB
123	select HAVE_ARCH_MMAP_RND_BITS		if MMU
124	select HAVE_ARCH_MMAP_RND_COMPAT_BITS	if MMU && COMPAT
125	select HAVE_ARCH_COMPAT_MMAP_BASES	if MMU && COMPAT
126	select HAVE_ARCH_PREL32_RELOCATIONS
127	select HAVE_ARCH_SECCOMP_FILTER
128	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
129	select HAVE_ARCH_TRACEHOOK
130	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
131	select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
132	select HAVE_ARCH_VMAP_STACK		if X86_64
133	select HAVE_ARCH_WITHIN_STACK_FRAMES
134	select HAVE_CMPXCHG_DOUBLE
135	select HAVE_CMPXCHG_LOCAL
136	select HAVE_CONTEXT_TRACKING		if X86_64
137	select HAVE_COPY_THREAD_TLS
138	select HAVE_C_RECORDMCOUNT
139	select HAVE_DEBUG_KMEMLEAK
140	select HAVE_DEBUG_STACKOVERFLOW
141	select HAVE_DMA_CONTIGUOUS
142	select HAVE_DYNAMIC_FTRACE
143	select HAVE_DYNAMIC_FTRACE_WITH_REGS
144	select HAVE_EBPF_JIT
145	select HAVE_EFFICIENT_UNALIGNED_ACCESS
146	select HAVE_EXIT_THREAD
147	select HAVE_FENTRY			if X86_64 || DYNAMIC_FTRACE
148	select HAVE_FTRACE_MCOUNT_RECORD
149	select HAVE_FUNCTION_GRAPH_TRACER
150	select HAVE_FUNCTION_TRACER
151	select HAVE_GCC_PLUGINS
152	select HAVE_HW_BREAKPOINT
153	select HAVE_IDE
154	select HAVE_IOREMAP_PROT
155	select HAVE_IRQ_EXIT_ON_IRQ_STACK	if X86_64
156	select HAVE_IRQ_TIME_ACCOUNTING
157	select HAVE_KERNEL_BZIP2
158	select HAVE_KERNEL_GZIP
159	select HAVE_KERNEL_LZ4
160	select HAVE_KERNEL_LZMA
161	select HAVE_KERNEL_LZO
162	select HAVE_KERNEL_XZ
163	select HAVE_KPROBES
164	select HAVE_KPROBES_ON_FTRACE
165	select HAVE_FUNCTION_ERROR_INJECTION
166	select HAVE_KRETPROBES
167	select HAVE_KVM
168	select HAVE_LIVEPATCH			if X86_64
169	select HAVE_MEMBLOCK
170	select HAVE_MEMBLOCK_NODE_MAP
171	select HAVE_MIXED_BREAKPOINTS_REGS
172	select HAVE_MOD_ARCH_SPECIFIC
173	select HAVE_NMI
174	select HAVE_OPROFILE
175	select HAVE_OPTPROBES
176	select HAVE_PCSPKR_PLATFORM
177	select HAVE_PERF_EVENTS
178	select HAVE_PERF_EVENTS_NMI
179	select HAVE_HARDLOCKUP_DETECTOR_PERF	if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
180	select HAVE_PERF_REGS
181	select HAVE_PERF_USER_STACK_DUMP
182	select HAVE_RCU_TABLE_FREE		if PARAVIRT
183	select HAVE_RCU_TABLE_INVALIDATE	if HAVE_RCU_TABLE_FREE
184	select HAVE_REGS_AND_STACK_ACCESS_API
185	select HAVE_RELIABLE_STACKTRACE		if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
186	select HAVE_STACKPROTECTOR		if CC_HAS_SANE_STACKPROTECTOR
187	select HAVE_STACK_VALIDATION		if X86_64
188	select HAVE_RSEQ
189	select HAVE_SYSCALL_TRACEPOINTS
190	select HAVE_UNSTABLE_SCHED_CLOCK
191	select HAVE_USER_RETURN_NOTIFIER
192	select HOTPLUG_SMT			if SMP
193	select IRQ_FORCED_THREADING
194	select NEED_SG_DMA_LENGTH
195	select PCI_LOCKLESS_CONFIG
196	select PERF_EVENTS
197	select RTC_LIB
198	select RTC_MC146818_LIB
199	select SPARSE_IRQ
200	select SRCU
201	select SYSCTL_EXCEPTION_TRACE
202	select THREAD_INFO_IN_TASK
203	select USER_STACKTRACE_SUPPORT
204	select VIRT_TO_BUS
205	select X86_FEATURE_NAMES		if PROC_FS
206
207config INSTRUCTION_DECODER
208	def_bool y
209	depends on KPROBES || PERF_EVENTS || UPROBES
210
211config OUTPUT_FORMAT
212	string
213	default "elf32-i386" if X86_32
214	default "elf64-x86-64" if X86_64
215
216config ARCH_DEFCONFIG
217	string
218	default "arch/x86/configs/i386_defconfig" if X86_32
219	default "arch/x86/configs/x86_64_defconfig" if X86_64
220
221config LOCKDEP_SUPPORT
222	def_bool y
223
224config STACKTRACE_SUPPORT
225	def_bool y
226
227config MMU
228	def_bool y
229
230config ARCH_MMAP_RND_BITS_MIN
231	default 28 if 64BIT
232	default 8
233
234config ARCH_MMAP_RND_BITS_MAX
235	default 32 if 64BIT
236	default 16
237
238config ARCH_MMAP_RND_COMPAT_BITS_MIN
239	default 8
240
241config ARCH_MMAP_RND_COMPAT_BITS_MAX
242	default 16
243
244config SBUS
245	bool
246
247config GENERIC_ISA_DMA
248	def_bool y
249	depends on ISA_DMA_API
250
251config GENERIC_BUG
252	def_bool y
253	depends on BUG
254	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
255
256config GENERIC_BUG_RELATIVE_POINTERS
257	bool
258
259config GENERIC_HWEIGHT
260	def_bool y
261
262config ARCH_MAY_HAVE_PC_FDC
263	def_bool y
264	depends on ISA_DMA_API
265
266config RWSEM_XCHGADD_ALGORITHM
267	def_bool y
268
269config GENERIC_CALIBRATE_DELAY
270	def_bool y
271
272config ARCH_HAS_CPU_RELAX
273	def_bool y
274
275config ARCH_HAS_CACHE_LINE_SIZE
276	def_bool y
277
278config ARCH_HAS_FILTER_PGPROT
279	def_bool y
280
281config HAVE_SETUP_PER_CPU_AREA
282	def_bool y
283
284config NEED_PER_CPU_EMBED_FIRST_CHUNK
285	def_bool y
286
287config NEED_PER_CPU_PAGE_FIRST_CHUNK
288	def_bool y
289
290config ARCH_HIBERNATION_POSSIBLE
291	def_bool y
292
293config ARCH_SUSPEND_POSSIBLE
294	def_bool y
295
296config ARCH_WANT_HUGE_PMD_SHARE
297	def_bool y
298
299config ARCH_WANT_GENERAL_HUGETLB
300	def_bool y
301
302config ZONE_DMA32
303	def_bool y if X86_64
304
305config AUDIT_ARCH
306	def_bool y if X86_64
307
308config ARCH_SUPPORTS_OPTIMIZED_INLINING
309	def_bool y
310
311config ARCH_SUPPORTS_DEBUG_PAGEALLOC
312	def_bool y
313
314config KASAN_SHADOW_OFFSET
315	hex
316	depends on KASAN
317	default 0xdffffc0000000000
318
319config HAVE_INTEL_TXT
320	def_bool y
321	depends on INTEL_IOMMU && ACPI
322
323config X86_32_SMP
324	def_bool y
325	depends on X86_32 && SMP
326
327config X86_64_SMP
328	def_bool y
329	depends on X86_64 && SMP
330
331config X86_32_LAZY_GS
332	def_bool y
333	depends on X86_32 && !STACKPROTECTOR
334
335config ARCH_SUPPORTS_UPROBES
336	def_bool y
337
338config FIX_EARLYCON_MEM
339	def_bool y
340
341config DYNAMIC_PHYSICAL_MASK
342	bool
343
344config PGTABLE_LEVELS
345	int
346	default 5 if X86_5LEVEL
347	default 4 if X86_64
348	default 3 if X86_PAE
349	default 2
350
351config CC_HAS_SANE_STACKPROTECTOR
352	bool
353	default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
354	default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
355	help
356	   We have to make sure stack protector is unconditionally disabled if
357	   the compiler produces broken code.
358
359menu "Processor type and features"
360
361config ZONE_DMA
362	bool "DMA memory allocation support" if EXPERT
363	default y
364	help
365	  DMA memory allocation support allows devices with less than 32-bit
366	  addressing to allocate within the first 16MB of address space.
367	  Disable if no such devices will be used.
368
369	  If unsure, say Y.
370
371config SMP
372	bool "Symmetric multi-processing support"
373	---help---
374	  This enables support for systems with more than one CPU. If you have
375	  a system with only one CPU, say N. If you have a system with more
376	  than one CPU, say Y.
377
378	  If you say N here, the kernel will run on uni- and multiprocessor
379	  machines, but will use only one CPU of a multiprocessor machine. If
380	  you say Y here, the kernel will run on many, but not all,
381	  uniprocessor machines. On a uniprocessor machine, the kernel
382	  will run faster if you say N here.
383
384	  Note that if you say Y here and choose architecture "586" or
385	  "Pentium" under "Processor family", the kernel will not work on 486
386	  architectures. Similarly, multiprocessor kernels for the "PPro"
387	  architecture may not work on all Pentium based boards.
388
389	  People using multiprocessor machines who say Y here should also say
390	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
391	  Management" code will be disabled if you say Y here.
392
393	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
394	  <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
395	  <http://www.tldp.org/docs.html#howto>.
396
397	  If you don't know what to do here, say N.
398
399config X86_FEATURE_NAMES
400	bool "Processor feature human-readable names" if EMBEDDED
401	default y
402	---help---
403	  This option compiles in a table of x86 feature bits and corresponding
404	  names.  This is required to support /proc/cpuinfo and a few kernel
405	  messages.  You can disable this to save space, at the expense of
406	  making those few kernel messages show numeric feature bits instead.
407
408	  If in doubt, say Y.
409
410config X86_X2APIC
411	bool "Support x2apic"
412	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
413	---help---
414	  This enables x2apic support on CPUs that have this feature.
415
416	  This allows 32-bit apic IDs (so it can support very large systems),
417	  and accesses the local apic via MSRs not via mmio.
418
419	  If you don't know what to do here, say N.
420
421config X86_MPPARSE
422	bool "Enable MPS table" if ACPI || SFI
423	default y
424	depends on X86_LOCAL_APIC
425	---help---
426	  For old smp systems that do not have proper acpi support. Newer systems
427	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
428
429config GOLDFISH
430       def_bool y
431       depends on X86_GOLDFISH
432
433config RETPOLINE
434	bool "Avoid speculative indirect branches in kernel"
435	default y
436	select STACK_VALIDATION if HAVE_STACK_VALIDATION
437	help
438	  Compile kernel with the retpoline compiler options to guard against
439	  kernel-to-user data leaks by avoiding speculative indirect
440	  branches. Requires a compiler with -mindirect-branch=thunk-extern
441	  support for full protection. The kernel may run slower.
442
443config INTEL_RDT
444	bool "Intel Resource Director Technology support"
445	default n
446	depends on X86 && CPU_SUP_INTEL
447	select KERNFS
448	help
449	  Select to enable resource allocation and monitoring which are
450	  sub-features of Intel Resource Director Technology(RDT). More
451	  information about RDT can be found in the Intel x86
452	  Architecture Software Developer Manual.
453
454	  Say N if unsure.
455
456if X86_32
457config X86_BIGSMP
458	bool "Support for big SMP systems with more than 8 CPUs"
459	depends on SMP
460	---help---
461	  This option is needed for the systems that have more than 8 CPUs
462
463config X86_EXTENDED_PLATFORM
464	bool "Support for extended (non-PC) x86 platforms"
465	default y
466	---help---
467	  If you disable this option then the kernel will only support
468	  standard PC platforms. (which covers the vast majority of
469	  systems out there.)
470
471	  If you enable this option then you'll be able to select support
472	  for the following (non-PC) 32 bit x86 platforms:
473		Goldfish (Android emulator)
474		AMD Elan
475		RDC R-321x SoC
476		SGI 320/540 (Visual Workstation)
477		STA2X11-based (e.g. Northville)
478		Moorestown MID devices
479
480	  If you have one of these systems, or if you want to build a
481	  generic distribution kernel, say Y here - otherwise say N.
482endif
483
484if X86_64
485config X86_EXTENDED_PLATFORM
486	bool "Support for extended (non-PC) x86 platforms"
487	default y
488	---help---
489	  If you disable this option then the kernel will only support
490	  standard PC platforms. (which covers the vast majority of
491	  systems out there.)
492
493	  If you enable this option then you'll be able to select support
494	  for the following (non-PC) 64 bit x86 platforms:
495		Numascale NumaChip
496		ScaleMP vSMP
497		SGI Ultraviolet
498
499	  If you have one of these systems, or if you want to build a
500	  generic distribution kernel, say Y here - otherwise say N.
501endif
502# This is an alphabetically sorted list of 64 bit extended platforms
503# Please maintain the alphabetic order if and when there are additions
504config X86_NUMACHIP
505	bool "Numascale NumaChip"
506	depends on X86_64
507	depends on X86_EXTENDED_PLATFORM
508	depends on NUMA
509	depends on SMP
510	depends on X86_X2APIC
511	depends on PCI_MMCONFIG
512	---help---
513	  Adds support for Numascale NumaChip large-SMP systems. Needed to
514	  enable more than ~168 cores.
515	  If you don't have one of these, you should say N here.
516
517config X86_VSMP
518	bool "ScaleMP vSMP"
519	select HYPERVISOR_GUEST
520	select PARAVIRT
521	depends on X86_64 && PCI
522	depends on X86_EXTENDED_PLATFORM
523	depends on SMP
524	---help---
525	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
526	  supposed to run on these EM64T-based machines.  Only choose this option
527	  if you have one of these machines.
528
529config X86_UV
530	bool "SGI Ultraviolet"
531	depends on X86_64
532	depends on X86_EXTENDED_PLATFORM
533	depends on NUMA
534	depends on EFI
535	depends on X86_X2APIC
536	depends on PCI
537	---help---
538	  This option is needed in order to support SGI Ultraviolet systems.
539	  If you don't have one of these, you should say N here.
540
541# Following is an alphabetically sorted list of 32 bit extended platforms
542# Please maintain the alphabetic order if and when there are additions
543
544config X86_GOLDFISH
545       bool "Goldfish (Virtual Platform)"
546       depends on X86_EXTENDED_PLATFORM
547       ---help---
548	 Enable support for the Goldfish virtual platform used primarily
549	 for Android development. Unless you are building for the Android
550	 Goldfish emulator say N here.
551
552config X86_INTEL_CE
553	bool "CE4100 TV platform"
554	depends on PCI
555	depends on PCI_GODIRECT
556	depends on X86_IO_APIC
557	depends on X86_32
558	depends on X86_EXTENDED_PLATFORM
559	select X86_REBOOTFIXUPS
560	select OF
561	select OF_EARLY_FLATTREE
562	---help---
563	  Select for the Intel CE media processor (CE4100) SOC.
564	  This option compiles in support for the CE4100 SOC for settop
565	  boxes and media devices.
566
567config X86_INTEL_MID
568	bool "Intel MID platform support"
569	depends on X86_EXTENDED_PLATFORM
570	depends on X86_PLATFORM_DEVICES
571	depends on PCI
572	depends on X86_64 || (PCI_GOANY && X86_32)
573	depends on X86_IO_APIC
574	select SFI
575	select I2C
576	select DW_APB_TIMER
577	select APB_TIMER
578	select INTEL_SCU_IPC
579	select MFD_INTEL_MSIC
580	---help---
581	  Select to build a kernel capable of supporting Intel MID (Mobile
582	  Internet Device) platform systems which do not have the PCI legacy
583	  interfaces. If you are building for a PC class system say N here.
584
585	  Intel MID platforms are based on an Intel processor and chipset which
586	  consume less power than most of the x86 derivatives.
587
588config X86_INTEL_QUARK
589	bool "Intel Quark platform support"
590	depends on X86_32
591	depends on X86_EXTENDED_PLATFORM
592	depends on X86_PLATFORM_DEVICES
593	depends on X86_TSC
594	depends on PCI
595	depends on PCI_GOANY
596	depends on X86_IO_APIC
597	select IOSF_MBI
598	select INTEL_IMR
599	select COMMON_CLK
600	---help---
601	  Select to include support for Quark X1000 SoC.
602	  Say Y here if you have a Quark based system such as the Arduino
603	  compatible Intel Galileo.
604
605config X86_INTEL_LPSS
606	bool "Intel Low Power Subsystem Support"
607	depends on X86 && ACPI
608	select COMMON_CLK
609	select PINCTRL
610	select IOSF_MBI
611	---help---
612	  Select to build support for Intel Low Power Subsystem such as
613	  found on Intel Lynxpoint PCH. Selecting this option enables
614	  things like clock tree (common clock framework) and pincontrol
615	  which are needed by the LPSS peripheral drivers.
616
617config X86_AMD_PLATFORM_DEVICE
618	bool "AMD ACPI2Platform devices support"
619	depends on ACPI
620	select COMMON_CLK
621	select PINCTRL
622	---help---
623	  Select to interpret AMD specific ACPI device to platform device
624	  such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
625	  I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
626	  implemented under PINCTRL subsystem.
627
628config IOSF_MBI
629	tristate "Intel SoC IOSF Sideband support for SoC platforms"
630	depends on PCI
631	---help---
632	  This option enables sideband register access support for Intel SoC
633	  platforms. On these platforms the IOSF sideband is used in lieu of
634	  MSR's for some register accesses, mostly but not limited to thermal
635	  and power. Drivers may query the availability of this device to
636	  determine if they need the sideband in order to work on these
637	  platforms. The sideband is available on the following SoC products.
638	  This list is not meant to be exclusive.
639	   - BayTrail
640	   - Braswell
641	   - Quark
642
643	  You should say Y if you are running a kernel on one of these SoC's.
644
645config IOSF_MBI_DEBUG
646	bool "Enable IOSF sideband access through debugfs"
647	depends on IOSF_MBI && DEBUG_FS
648	---help---
649	  Select this option to expose the IOSF sideband access registers (MCR,
650	  MDR, MCRX) through debugfs to write and read register information from
651	  different units on the SoC. This is most useful for obtaining device
652	  state information for debug and analysis. As this is a general access
653	  mechanism, users of this option would have specific knowledge of the
654	  device they want to access.
655
656	  If you don't require the option or are in doubt, say N.
657
658config X86_RDC321X
659	bool "RDC R-321x SoC"
660	depends on X86_32
661	depends on X86_EXTENDED_PLATFORM
662	select M486
663	select X86_REBOOTFIXUPS
664	---help---
665	  This option is needed for RDC R-321x system-on-chip, also known
666	  as R-8610-(G).
667	  If you don't have one of these chips, you should say N here.
668
669config X86_32_NON_STANDARD
670	bool "Support non-standard 32-bit SMP architectures"
671	depends on X86_32 && SMP
672	depends on X86_EXTENDED_PLATFORM
673	---help---
674	  This option compiles in the bigsmp and STA2X11 default
675	  subarchitectures.  It is intended for a generic binary
676	  kernel. If you select them all, kernel will probe it one by
677	  one and will fallback to default.
678
679# Alphabetically sorted list of Non standard 32 bit platforms
680
681config X86_SUPPORTS_MEMORY_FAILURE
682	def_bool y
683	# MCE code calls memory_failure():
684	depends on X86_MCE
685	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
686	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
687	depends on X86_64 || !SPARSEMEM
688	select ARCH_SUPPORTS_MEMORY_FAILURE
689
690config STA2X11
691	bool "STA2X11 Companion Chip Support"
692	depends on X86_32_NON_STANDARD && PCI
693	select ARCH_HAS_PHYS_TO_DMA
694	select X86_DEV_DMA_OPS
695	select X86_DMA_REMAP
696	select SWIOTLB
697	select MFD_STA2X11
698	select GPIOLIB
699	default n
700	---help---
701	  This adds support for boards based on the STA2X11 IO-Hub,
702	  a.k.a. "ConneXt". The chip is used in place of the standard
703	  PC chipset, so all "standard" peripherals are missing. If this
704	  option is selected the kernel will still be able to boot on
705	  standard PC machines.
706
707config X86_32_IRIS
708	tristate "Eurobraille/Iris poweroff module"
709	depends on X86_32
710	---help---
711	  The Iris machines from EuroBraille do not have APM or ACPI support
712	  to shut themselves down properly.  A special I/O sequence is
713	  needed to do so, which is what this module does at
714	  kernel shutdown.
715
716	  This is only for Iris machines from EuroBraille.
717
718	  If unused, say N.
719
720config SCHED_OMIT_FRAME_POINTER
721	def_bool y
722	prompt "Single-depth WCHAN output"
723	depends on X86
724	---help---
725	  Calculate simpler /proc/<PID>/wchan values. If this option
726	  is disabled then wchan values will recurse back to the
727	  caller function. This provides more accurate wchan values,
728	  at the expense of slightly more scheduling overhead.
729
730	  If in doubt, say "Y".
731
732menuconfig HYPERVISOR_GUEST
733	bool "Linux guest support"
734	---help---
735	  Say Y here to enable options for running Linux under various hyper-
736	  visors. This option enables basic hypervisor detection and platform
737	  setup.
738
739	  If you say N, all options in this submenu will be skipped and
740	  disabled, and Linux guest support won't be built in.
741
742if HYPERVISOR_GUEST
743
744config PARAVIRT
745	bool "Enable paravirtualization code"
746	---help---
747	  This changes the kernel so it can modify itself when it is run
748	  under a hypervisor, potentially improving performance significantly
749	  over full virtualization.  However, when run without a hypervisor
750	  the kernel is theoretically slower and slightly larger.
751
752config PARAVIRT_DEBUG
753	bool "paravirt-ops debugging"
754	depends on PARAVIRT && DEBUG_KERNEL
755	---help---
756	  Enable to debug paravirt_ops internals.  Specifically, BUG if
757	  a paravirt_op is missing when it is called.
758
759config PARAVIRT_SPINLOCKS
760	bool "Paravirtualization layer for spinlocks"
761	depends on PARAVIRT && SMP
762	---help---
763	  Paravirtualized spinlocks allow a pvops backend to replace the
764	  spinlock implementation with something virtualization-friendly
765	  (for example, block the virtual CPU rather than spinning).
766
767	  It has a minimal impact on native kernels and gives a nice performance
768	  benefit on paravirtualized KVM / Xen kernels.
769
770	  If you are unsure how to answer this question, answer Y.
771
772config QUEUED_LOCK_STAT
773	bool "Paravirt queued spinlock statistics"
774	depends on PARAVIRT_SPINLOCKS && DEBUG_FS
775	---help---
776	  Enable the collection of statistical data on the slowpath
777	  behavior of paravirtualized queued spinlocks and report
778	  them on debugfs.
779
780source "arch/x86/xen/Kconfig"
781
782config KVM_GUEST
783	bool "KVM Guest support (including kvmclock)"
784	depends on PARAVIRT
785	select PARAVIRT_CLOCK
786	default y
787	---help---
788	  This option enables various optimizations for running under the KVM
789	  hypervisor. It includes a paravirtualized clock, so that instead
790	  of relying on a PIT (or probably other) emulation by the
791	  underlying device model, the host provides the guest with
792	  timing infrastructure such as time of day, and system time
793
794config KVM_DEBUG_FS
795	bool "Enable debug information for KVM Guests in debugfs"
796	depends on KVM_GUEST && DEBUG_FS
797	default n
798	---help---
799	  This option enables collection of various statistics for KVM guest.
800	  Statistics are displayed in debugfs filesystem. Enabling this option
801	  may incur significant overhead.
802
803config PARAVIRT_TIME_ACCOUNTING
804	bool "Paravirtual steal time accounting"
805	depends on PARAVIRT
806	default n
807	---help---
808	  Select this option to enable fine granularity task steal time
809	  accounting. Time spent executing other tasks in parallel with
810	  the current vCPU is discounted from the vCPU power. To account for
811	  that, there can be a small performance impact.
812
813	  If in doubt, say N here.
814
815config PARAVIRT_CLOCK
816	bool
817
818config JAILHOUSE_GUEST
819	bool "Jailhouse non-root cell support"
820	depends on X86_64 && PCI
821	select X86_PM_TIMER
822	---help---
823	  This option allows to run Linux as guest in a Jailhouse non-root
824	  cell. You can leave this option disabled if you only want to start
825	  Jailhouse and run Linux afterwards in the root cell.
826
827endif #HYPERVISOR_GUEST
828
829config NO_BOOTMEM
830	def_bool y
831
832source "arch/x86/Kconfig.cpu"
833
834config HPET_TIMER
835	def_bool X86_64
836	prompt "HPET Timer Support" if X86_32
837	---help---
838	  Use the IA-PC HPET (High Precision Event Timer) to manage
839	  time in preference to the PIT and RTC, if a HPET is
840	  present.
841	  HPET is the next generation timer replacing legacy 8254s.
842	  The HPET provides a stable time base on SMP
843	  systems, unlike the TSC, but it is more expensive to access,
844	  as it is off-chip.  The interface used is documented
845	  in the HPET spec, revision 1.
846
847	  You can safely choose Y here.  However, HPET will only be
848	  activated if the platform and the BIOS support this feature.
849	  Otherwise the 8254 will be used for timing services.
850
851	  Choose N to continue using the legacy 8254 timer.
852
853config HPET_EMULATE_RTC
854	def_bool y
855	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
856
857config APB_TIMER
858       def_bool y if X86_INTEL_MID
859       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
860       select DW_APB_TIMER
861       depends on X86_INTEL_MID && SFI
862       help
863         APB timer is the replacement for 8254, HPET on X86 MID platforms.
864         The APBT provides a stable time base on SMP
865         systems, unlike the TSC, but it is more expensive to access,
866         as it is off-chip. APB timers are always running regardless of CPU
867         C states, they are used as per CPU clockevent device when possible.
868
869# Mark as expert because too many people got it wrong.
870# The code disables itself when not needed.
871config DMI
872	default y
873	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
874	bool "Enable DMI scanning" if EXPERT
875	---help---
876	  Enabled scanning of DMI to identify machine quirks. Say Y
877	  here unless you have verified that your setup is not
878	  affected by entries in the DMI blacklist. Required by PNP
879	  BIOS code.
880
881config GART_IOMMU
882	bool "Old AMD GART IOMMU support"
883	select IOMMU_HELPER
884	select SWIOTLB
885	depends on X86_64 && PCI && AMD_NB
886	---help---
887	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
888	  GART based hardware IOMMUs.
889
890	  The GART supports full DMA access for devices with 32-bit access
891	  limitations, on systems with more than 3 GB. This is usually needed
892	  for USB, sound, many IDE/SATA chipsets and some other devices.
893
894	  Newer systems typically have a modern AMD IOMMU, supported via
895	  the CONFIG_AMD_IOMMU=y config option.
896
897	  In normal configurations this driver is only active when needed:
898	  there's more than 3 GB of memory and the system contains a
899	  32-bit limited device.
900
901	  If unsure, say Y.
902
903config CALGARY_IOMMU
904	bool "IBM Calgary IOMMU support"
905	select IOMMU_HELPER
906	select SWIOTLB
907	depends on X86_64 && PCI
908	---help---
909	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
910	  systems. Needed to run systems with more than 3GB of memory
911	  properly with 32-bit PCI devices that do not support DAC
912	  (Double Address Cycle). Calgary also supports bus level
913	  isolation, where all DMAs pass through the IOMMU.  This
914	  prevents them from going anywhere except their intended
915	  destination. This catches hard-to-find kernel bugs and
916	  mis-behaving drivers and devices that do not use the DMA-API
917	  properly to set up their DMA buffers.  The IOMMU can be
918	  turned off at boot time with the iommu=off parameter.
919	  Normally the kernel will make the right choice by itself.
920	  If unsure, say Y.
921
922config CALGARY_IOMMU_ENABLED_BY_DEFAULT
923	def_bool y
924	prompt "Should Calgary be enabled by default?"
925	depends on CALGARY_IOMMU
926	---help---
927	  Should Calgary be enabled by default? if you choose 'y', Calgary
928	  will be used (if it exists). If you choose 'n', Calgary will not be
929	  used even if it exists. If you choose 'n' and would like to use
930	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
931	  If unsure, say Y.
932
933config MAXSMP
934	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
935	depends on X86_64 && SMP && DEBUG_KERNEL
936	select CPUMASK_OFFSTACK
937	---help---
938	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
939	  If unsure, say N.
940
941#
942# The maximum number of CPUs supported:
943#
944# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT,
945# and which can be configured interactively in the
946# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range.
947#
948# The ranges are different on 32-bit and 64-bit kernels, depending on
949# hardware capabilities and scalability features of the kernel.
950#
951# ( If MAXSMP is enabled we just use the highest possible value and disable
952#   interactive configuration. )
953#
954
955config NR_CPUS_RANGE_BEGIN
956	int
957	default NR_CPUS_RANGE_END if MAXSMP
958	default    1 if !SMP
959	default    2
960
961config NR_CPUS_RANGE_END
962	int
963	depends on X86_32
964	default   64 if  SMP &&  X86_BIGSMP
965	default    8 if  SMP && !X86_BIGSMP
966	default    1 if !SMP
967
968config NR_CPUS_RANGE_END
969	int
970	depends on X86_64
971	default 8192 if  SMP && ( MAXSMP ||  CPUMASK_OFFSTACK)
972	default  512 if  SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
973	default    1 if !SMP
974
975config NR_CPUS_DEFAULT
976	int
977	depends on X86_32
978	default   32 if  X86_BIGSMP
979	default    8 if  SMP
980	default    1 if !SMP
981
982config NR_CPUS_DEFAULT
983	int
984	depends on X86_64
985	default 8192 if  MAXSMP
986	default   64 if  SMP
987	default    1 if !SMP
988
989config NR_CPUS
990	int "Maximum number of CPUs" if SMP && !MAXSMP
991	range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END
992	default NR_CPUS_DEFAULT
993	---help---
994	  This allows you to specify the maximum number of CPUs which this
995	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
996	  supported value is 8192, otherwise the maximum value is 512.  The
997	  minimum value which makes sense is 2.
998
999	  This is purely to save memory: each supported CPU adds about 8KB
1000	  to the kernel image.
1001
1002config SCHED_SMT
1003	def_bool y if SMP
1004
1005config SCHED_MC
1006	def_bool y
1007	prompt "Multi-core scheduler support"
1008	depends on SMP
1009	---help---
1010	  Multi-core scheduler support improves the CPU scheduler's decision
1011	  making when dealing with multi-core CPU chips at a cost of slightly
1012	  increased overhead in some places. If unsure say N here.
1013
1014config SCHED_MC_PRIO
1015	bool "CPU core priorities scheduler support"
1016	depends on SCHED_MC && CPU_SUP_INTEL
1017	select X86_INTEL_PSTATE
1018	select CPU_FREQ
1019	default y
1020	---help---
1021	  Intel Turbo Boost Max Technology 3.0 enabled CPUs have a
1022	  core ordering determined at manufacturing time, which allows
1023	  certain cores to reach higher turbo frequencies (when running
1024	  single threaded workloads) than others.
1025
1026	  Enabling this kernel feature teaches the scheduler about
1027	  the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the
1028	  scheduler's CPU selection logic accordingly, so that higher
1029	  overall system performance can be achieved.
1030
1031	  This feature will have no effect on CPUs without this feature.
1032
1033	  If unsure say Y here.
1034
1035config UP_LATE_INIT
1036       def_bool y
1037       depends on !SMP && X86_LOCAL_APIC
1038
1039config X86_UP_APIC
1040	bool "Local APIC support on uniprocessors" if !PCI_MSI
1041	default PCI_MSI
1042	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
1043	---help---
1044	  A local APIC (Advanced Programmable Interrupt Controller) is an
1045	  integrated interrupt controller in the CPU. If you have a single-CPU
1046	  system which has a processor with a local APIC, you can say Y here to
1047	  enable and use it. If you say Y here even though your machine doesn't
1048	  have a local APIC, then the kernel will still run with no slowdown at
1049	  all. The local APIC supports CPU-generated self-interrupts (timer,
1050	  performance counters), and the NMI watchdog which detects hard
1051	  lockups.
1052
1053config X86_UP_IOAPIC
1054	bool "IO-APIC support on uniprocessors"
1055	depends on X86_UP_APIC
1056	---help---
1057	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
1058	  SMP-capable replacement for PC-style interrupt controllers. Most
1059	  SMP systems and many recent uniprocessor systems have one.
1060
1061	  If you have a single-CPU system with an IO-APIC, you can say Y here
1062	  to use it. If you say Y here even though your machine doesn't have
1063	  an IO-APIC, then the kernel will still run with no slowdown at all.
1064
1065config X86_LOCAL_APIC
1066	def_bool y
1067	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
1068	select IRQ_DOMAIN_HIERARCHY
1069	select PCI_MSI_IRQ_DOMAIN if PCI_MSI
1070
1071config X86_IO_APIC
1072	def_bool y
1073	depends on X86_LOCAL_APIC || X86_UP_IOAPIC
1074
1075config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
1076	bool "Reroute for broken boot IRQs"
1077	depends on X86_IO_APIC
1078	---help---
1079	  This option enables a workaround that fixes a source of
1080	  spurious interrupts. This is recommended when threaded
1081	  interrupt handling is used on systems where the generation of
1082	  superfluous "boot interrupts" cannot be disabled.
1083
1084	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1085	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
1086	  kernel does during interrupt handling). On chipsets where this
1087	  boot IRQ generation cannot be disabled, this workaround keeps
1088	  the original IRQ line masked so that only the equivalent "boot
1089	  IRQ" is delivered to the CPUs. The workaround also tells the
1090	  kernel to set up the IRQ handler on the boot IRQ line. In this
1091	  way only one interrupt is delivered to the kernel. Otherwise
1092	  the spurious second interrupt may cause the kernel to bring
1093	  down (vital) interrupt lines.
1094
1095	  Only affects "broken" chipsets. Interrupt sharing may be
1096	  increased on these systems.
1097
1098config X86_MCE
1099	bool "Machine Check / overheating reporting"
1100	select GENERIC_ALLOCATOR
1101	default y
1102	---help---
1103	  Machine Check support allows the processor to notify the
1104	  kernel if it detects a problem (e.g. overheating, data corruption).
1105	  The action the kernel takes depends on the severity of the problem,
1106	  ranging from warning messages to halting the machine.
1107
1108config X86_MCELOG_LEGACY
1109	bool "Support for deprecated /dev/mcelog character device"
1110	depends on X86_MCE
1111	---help---
1112	  Enable support for /dev/mcelog which is needed by the old mcelog
1113	  userspace logging daemon. Consider switching to the new generation
1114	  rasdaemon solution.
1115
1116config X86_MCE_INTEL
1117	def_bool y
1118	prompt "Intel MCE features"
1119	depends on X86_MCE && X86_LOCAL_APIC
1120	---help---
1121	   Additional support for intel specific MCE features such as
1122	   the thermal monitor.
1123
1124config X86_MCE_AMD
1125	def_bool y
1126	prompt "AMD MCE features"
1127	depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
1128	---help---
1129	   Additional support for AMD specific MCE features such as
1130	   the DRAM Error Threshold.
1131
1132config X86_ANCIENT_MCE
1133	bool "Support for old Pentium 5 / WinChip machine checks"
1134	depends on X86_32 && X86_MCE
1135	---help---
1136	  Include support for machine check handling on old Pentium 5 or WinChip
1137	  systems. These typically need to be enabled explicitly on the command
1138	  line.
1139
1140config X86_MCE_THRESHOLD
1141	depends on X86_MCE_AMD || X86_MCE_INTEL
1142	def_bool y
1143
1144config X86_MCE_INJECT
1145	depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
1146	tristate "Machine check injector support"
1147	---help---
1148	  Provide support for injecting machine checks for testing purposes.
1149	  If you don't know what a machine check is and you don't do kernel
1150	  QA it is safe to say n.
1151
1152config X86_THERMAL_VECTOR
1153	def_bool y
1154	depends on X86_MCE_INTEL
1155
1156source "arch/x86/events/Kconfig"
1157
1158config X86_LEGACY_VM86
1159	bool "Legacy VM86 support"
1160	default n
1161	depends on X86_32
1162	---help---
1163	  This option allows user programs to put the CPU into V8086
1164	  mode, which is an 80286-era approximation of 16-bit real mode.
1165
1166	  Some very old versions of X and/or vbetool require this option
1167	  for user mode setting.  Similarly, DOSEMU will use it if
1168	  available to accelerate real mode DOS programs.  However, any
1169	  recent version of DOSEMU, X, or vbetool should be fully
1170	  functional even without kernel VM86 support, as they will all
1171	  fall back to software emulation. Nevertheless, if you are using
1172	  a 16-bit DOS program where 16-bit performance matters, vm86
1173	  mode might be faster than emulation and you might want to
1174	  enable this option.
1175
1176	  Note that any app that works on a 64-bit kernel is unlikely to
1177	  need this option, as 64-bit kernels don't, and can't, support
1178	  V8086 mode. This option is also unrelated to 16-bit protected
1179	  mode and is not needed to run most 16-bit programs under Wine.
1180
1181	  Enabling this option increases the complexity of the kernel
1182	  and slows down exception handling a tiny bit.
1183
1184	  If unsure, say N here.
1185
1186config VM86
1187       bool
1188       default X86_LEGACY_VM86
1189
1190config X86_16BIT
1191	bool "Enable support for 16-bit segments" if EXPERT
1192	default y
1193	depends on MODIFY_LDT_SYSCALL
1194	---help---
1195	  This option is required by programs like Wine to run 16-bit
1196	  protected mode legacy code on x86 processors.  Disabling
1197	  this option saves about 300 bytes on i386, or around 6K text
1198	  plus 16K runtime memory on x86-64,
1199
1200config X86_ESPFIX32
1201	def_bool y
1202	depends on X86_16BIT && X86_32
1203
1204config X86_ESPFIX64
1205	def_bool y
1206	depends on X86_16BIT && X86_64
1207
1208config X86_VSYSCALL_EMULATION
1209       bool "Enable vsyscall emulation" if EXPERT
1210       default y
1211       depends on X86_64
1212       ---help---
1213	 This enables emulation of the legacy vsyscall page.  Disabling
1214	 it is roughly equivalent to booting with vsyscall=none, except
1215	 that it will also disable the helpful warning if a program
1216	 tries to use a vsyscall.  With this option set to N, offending
1217	 programs will just segfault, citing addresses of the form
1218	 0xffffffffff600?00.
1219
1220	 This option is required by many programs built before 2013, and
1221	 care should be used even with newer programs if set to N.
1222
1223	 Disabling this option saves about 7K of kernel size and
1224	 possibly 4K of additional runtime pagetable memory.
1225
1226config TOSHIBA
1227	tristate "Toshiba Laptop support"
1228	depends on X86_32
1229	---help---
1230	  This adds a driver to safely access the System Management Mode of
1231	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1232	  not work on models with a Phoenix BIOS. The System Management Mode
1233	  is used to set the BIOS and power saving options on Toshiba portables.
1234
1235	  For information on utilities to make use of this driver see the
1236	  Toshiba Linux utilities web site at:
1237	  <http://www.buzzard.org.uk/toshiba/>.
1238
1239	  Say Y if you intend to run this kernel on a Toshiba portable.
1240	  Say N otherwise.
1241
1242config I8K
1243	tristate "Dell i8k legacy laptop support"
1244	select HWMON
1245	select SENSORS_DELL_SMM
1246	---help---
1247	  This option enables legacy /proc/i8k userspace interface in hwmon
1248	  dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1249	  temperature and allows controlling fan speeds of Dell laptops via
1250	  System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1251	  it reports also power and hotkey status. For fan speed control is
1252	  needed userspace package i8kutils.
1253
1254	  Say Y if you intend to run this kernel on old Dell laptops or want to
1255	  use userspace package i8kutils.
1256	  Say N otherwise.
1257
1258config X86_REBOOTFIXUPS
1259	bool "Enable X86 board specific fixups for reboot"
1260	depends on X86_32
1261	---help---
1262	  This enables chipset and/or board specific fixups to be done
1263	  in order to get reboot to work correctly. This is only needed on
1264	  some combinations of hardware and BIOS. The symptom, for which
1265	  this config is intended, is when reboot ends with a stalled/hung
1266	  system.
1267
1268	  Currently, the only fixup is for the Geode machines using
1269	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1270
1271	  Say Y if you want to enable the fixup. Currently, it's safe to
1272	  enable this option even if you don't need it.
1273	  Say N otherwise.
1274
1275config MICROCODE
1276	bool "CPU microcode loading support"
1277	default y
1278	depends on CPU_SUP_AMD || CPU_SUP_INTEL
1279	select FW_LOADER
1280	---help---
1281	  If you say Y here, you will be able to update the microcode on
1282	  Intel and AMD processors. The Intel support is for the IA32 family,
1283	  e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1284	  AMD support is for families 0x10 and later. You will obviously need
1285	  the actual microcode binary data itself which is not shipped with
1286	  the Linux kernel.
1287
1288	  The preferred method to load microcode from a detached initrd is described
1289	  in Documentation/x86/microcode.txt. For that you need to enable
1290	  CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1291	  initrd for microcode blobs.
1292
1293	  In addition, you can build the microcode into the kernel. For that you
1294	  need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
1295	  config option.
1296
1297config MICROCODE_INTEL
1298	bool "Intel microcode loading support"
1299	depends on MICROCODE
1300	default MICROCODE
1301	select FW_LOADER
1302	---help---
1303	  This options enables microcode patch loading support for Intel
1304	  processors.
1305
1306	  For the current Intel microcode data package go to
1307	  <https://downloadcenter.intel.com> and search for
1308	  'Linux Processor Microcode Data File'.
1309
1310config MICROCODE_AMD
1311	bool "AMD microcode loading support"
1312	depends on MICROCODE
1313	select FW_LOADER
1314	---help---
1315	  If you select this option, microcode patch loading support for AMD
1316	  processors will be enabled.
1317
1318config MICROCODE_OLD_INTERFACE
1319	def_bool y
1320	depends on MICROCODE
1321
1322config X86_MSR
1323	tristate "/dev/cpu/*/msr - Model-specific register support"
1324	---help---
1325	  This device gives privileged processes access to the x86
1326	  Model-Specific Registers (MSRs).  It is a character device with
1327	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1328	  MSR accesses are directed to a specific CPU on multi-processor
1329	  systems.
1330
1331config X86_CPUID
1332	tristate "/dev/cpu/*/cpuid - CPU information support"
1333	---help---
1334	  This device gives processes access to the x86 CPUID instruction to
1335	  be executed on a specific processor.  It is a character device
1336	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1337	  /dev/cpu/31/cpuid.
1338
1339choice
1340	prompt "High Memory Support"
1341	default HIGHMEM4G
1342	depends on X86_32
1343
1344config NOHIGHMEM
1345	bool "off"
1346	---help---
1347	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1348	  However, the address space of 32-bit x86 processors is only 4
1349	  Gigabytes large. That means that, if you have a large amount of
1350	  physical memory, not all of it can be "permanently mapped" by the
1351	  kernel. The physical memory that's not permanently mapped is called
1352	  "high memory".
1353
1354	  If you are compiling a kernel which will never run on a machine with
1355	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1356	  choice and suitable for most users). This will result in a "3GB/1GB"
1357	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1358	  space and the remaining part of the 4GB virtual memory space is used
1359	  by the kernel to permanently map as much physical memory as
1360	  possible.
1361
1362	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1363	  answer "4GB" here.
1364
1365	  If more than 4 Gigabytes is used then answer "64GB" here. This
1366	  selection turns Intel PAE (Physical Address Extension) mode on.
1367	  PAE implements 3-level paging on IA32 processors. PAE is fully
1368	  supported by Linux, PAE mode is implemented on all recent Intel
1369	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1370	  then the kernel will not boot on CPUs that don't support PAE!
1371
1372	  The actual amount of total physical memory will either be
1373	  auto detected or can be forced by using a kernel command line option
1374	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1375	  your boot loader (lilo or loadlin) about how to pass options to the
1376	  kernel at boot time.)
1377
1378	  If unsure, say "off".
1379
1380config HIGHMEM4G
1381	bool "4GB"
1382	---help---
1383	  Select this if you have a 32-bit processor and between 1 and 4
1384	  gigabytes of physical RAM.
1385
1386config HIGHMEM64G
1387	bool "64GB"
1388	depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6
1389	select X86_PAE
1390	---help---
1391	  Select this if you have a 32-bit processor and more than 4
1392	  gigabytes of physical RAM.
1393
1394endchoice
1395
1396choice
1397	prompt "Memory split" if EXPERT
1398	default VMSPLIT_3G
1399	depends on X86_32
1400	---help---
1401	  Select the desired split between kernel and user memory.
1402
1403	  If the address range available to the kernel is less than the
1404	  physical memory installed, the remaining memory will be available
1405	  as "high memory". Accessing high memory is a little more costly
1406	  than low memory, as it needs to be mapped into the kernel first.
1407	  Note that increasing the kernel address space limits the range
1408	  available to user programs, making the address space there
1409	  tighter.  Selecting anything other than the default 3G/1G split
1410	  will also likely make your kernel incompatible with binary-only
1411	  kernel modules.
1412
1413	  If you are not absolutely sure what you are doing, leave this
1414	  option alone!
1415
1416	config VMSPLIT_3G
1417		bool "3G/1G user/kernel split"
1418	config VMSPLIT_3G_OPT
1419		depends on !X86_PAE
1420		bool "3G/1G user/kernel split (for full 1G low memory)"
1421	config VMSPLIT_2G
1422		bool "2G/2G user/kernel split"
1423	config VMSPLIT_2G_OPT
1424		depends on !X86_PAE
1425		bool "2G/2G user/kernel split (for full 2G low memory)"
1426	config VMSPLIT_1G
1427		bool "1G/3G user/kernel split"
1428endchoice
1429
1430config PAGE_OFFSET
1431	hex
1432	default 0xB0000000 if VMSPLIT_3G_OPT
1433	default 0x80000000 if VMSPLIT_2G
1434	default 0x78000000 if VMSPLIT_2G_OPT
1435	default 0x40000000 if VMSPLIT_1G
1436	default 0xC0000000
1437	depends on X86_32
1438
1439config HIGHMEM
1440	def_bool y
1441	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1442
1443config X86_PAE
1444	bool "PAE (Physical Address Extension) Support"
1445	depends on X86_32 && !HIGHMEM4G
1446	select PHYS_ADDR_T_64BIT
1447	select SWIOTLB
1448	---help---
1449	  PAE is required for NX support, and furthermore enables
1450	  larger swapspace support for non-overcommit purposes. It
1451	  has the cost of more pagetable lookup overhead, and also
1452	  consumes more pagetable space per process.
1453
1454config X86_5LEVEL
1455	bool "Enable 5-level page tables support"
1456	select DYNAMIC_MEMORY_LAYOUT
1457	select SPARSEMEM_VMEMMAP
1458	depends on X86_64
1459	---help---
1460	  5-level paging enables access to larger address space:
1461	  upto 128 PiB of virtual address space and 4 PiB of
1462	  physical address space.
1463
1464	  It will be supported by future Intel CPUs.
1465
1466	  A kernel with the option enabled can be booted on machines that
1467	  support 4- or 5-level paging.
1468
1469	  See Documentation/x86/x86_64/5level-paging.txt for more
1470	  information.
1471
1472	  Say N if unsure.
1473
1474config X86_DIRECT_GBPAGES
1475	def_bool y
1476	depends on X86_64 && !DEBUG_PAGEALLOC
1477	---help---
1478	  Certain kernel features effectively disable kernel
1479	  linear 1 GB mappings (even if the CPU otherwise
1480	  supports them), so don't confuse the user by printing
1481	  that we have them enabled.
1482
1483config ARCH_HAS_MEM_ENCRYPT
1484	def_bool y
1485
1486config AMD_MEM_ENCRYPT
1487	bool "AMD Secure Memory Encryption (SME) support"
1488	depends on X86_64 && CPU_SUP_AMD
1489	select DYNAMIC_PHYSICAL_MASK
1490	---help---
1491	  Say yes to enable support for the encryption of system memory.
1492	  This requires an AMD processor that supports Secure Memory
1493	  Encryption (SME).
1494
1495config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT
1496	bool "Activate AMD Secure Memory Encryption (SME) by default"
1497	default y
1498	depends on AMD_MEM_ENCRYPT
1499	---help---
1500	  Say yes to have system memory encrypted by default if running on
1501	  an AMD processor that supports Secure Memory Encryption (SME).
1502
1503	  If set to Y, then the encryption of system memory can be
1504	  deactivated with the mem_encrypt=off command line option.
1505
1506	  If set to N, then the encryption of system memory can be
1507	  activated with the mem_encrypt=on command line option.
1508
1509config ARCH_USE_MEMREMAP_PROT
1510	def_bool y
1511	depends on AMD_MEM_ENCRYPT
1512
1513# Common NUMA Features
1514config NUMA
1515	bool "Numa Memory Allocation and Scheduler Support"
1516	depends on SMP
1517	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1518	default y if X86_BIGSMP
1519	---help---
1520	  Enable NUMA (Non Uniform Memory Access) support.
1521
1522	  The kernel will try to allocate memory used by a CPU on the
1523	  local memory controller of the CPU and add some more
1524	  NUMA awareness to the kernel.
1525
1526	  For 64-bit this is recommended if the system is Intel Core i7
1527	  (or later), AMD Opteron, or EM64T NUMA.
1528
1529	  For 32-bit this is only needed if you boot a 32-bit
1530	  kernel on a 64-bit NUMA platform.
1531
1532	  Otherwise, you should say N.
1533
1534config AMD_NUMA
1535	def_bool y
1536	prompt "Old style AMD Opteron NUMA detection"
1537	depends on X86_64 && NUMA && PCI
1538	---help---
1539	  Enable AMD NUMA node topology detection.  You should say Y here if
1540	  you have a multi processor AMD system. This uses an old method to
1541	  read the NUMA configuration directly from the builtin Northbridge
1542	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1543	  which also takes priority if both are compiled in.
1544
1545config X86_64_ACPI_NUMA
1546	def_bool y
1547	prompt "ACPI NUMA detection"
1548	depends on X86_64 && NUMA && ACPI && PCI
1549	select ACPI_NUMA
1550	---help---
1551	  Enable ACPI SRAT based node topology detection.
1552
1553# Some NUMA nodes have memory ranges that span
1554# other nodes.  Even though a pfn is valid and
1555# between a node's start and end pfns, it may not
1556# reside on that node.  See memmap_init_zone()
1557# for details.
1558config NODES_SPAN_OTHER_NODES
1559	def_bool y
1560	depends on X86_64_ACPI_NUMA
1561
1562config NUMA_EMU
1563	bool "NUMA emulation"
1564	depends on NUMA
1565	---help---
1566	  Enable NUMA emulation. A flat machine will be split
1567	  into virtual nodes when booted with "numa=fake=N", where N is the
1568	  number of nodes. This is only useful for debugging.
1569
1570config NODES_SHIFT
1571	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1572	range 1 10
1573	default "10" if MAXSMP
1574	default "6" if X86_64
1575	default "3"
1576	depends on NEED_MULTIPLE_NODES
1577	---help---
1578	  Specify the maximum number of NUMA Nodes available on the target
1579	  system.  Increases memory reserved to accommodate various tables.
1580
1581config ARCH_HAVE_MEMORY_PRESENT
1582	def_bool y
1583	depends on X86_32 && DISCONTIGMEM
1584
1585config ARCH_FLATMEM_ENABLE
1586	def_bool y
1587	depends on X86_32 && !NUMA
1588
1589config ARCH_DISCONTIGMEM_ENABLE
1590	def_bool y
1591	depends on NUMA && X86_32
1592
1593config ARCH_DISCONTIGMEM_DEFAULT
1594	def_bool y
1595	depends on NUMA && X86_32
1596
1597config ARCH_SPARSEMEM_ENABLE
1598	def_bool y
1599	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1600	select SPARSEMEM_STATIC if X86_32
1601	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1602
1603config ARCH_SPARSEMEM_DEFAULT
1604	def_bool y
1605	depends on X86_64
1606
1607config ARCH_SELECT_MEMORY_MODEL
1608	def_bool y
1609	depends on ARCH_SPARSEMEM_ENABLE
1610
1611config ARCH_MEMORY_PROBE
1612	bool "Enable sysfs memory/probe interface"
1613	depends on X86_64 && MEMORY_HOTPLUG
1614	help
1615	  This option enables a sysfs memory/probe interface for testing.
1616	  See Documentation/memory-hotplug.txt for more information.
1617	  If you are unsure how to answer this question, answer N.
1618
1619config ARCH_PROC_KCORE_TEXT
1620	def_bool y
1621	depends on X86_64 && PROC_KCORE
1622
1623config ILLEGAL_POINTER_VALUE
1624       hex
1625       default 0 if X86_32
1626       default 0xdead000000000000 if X86_64
1627
1628config X86_PMEM_LEGACY_DEVICE
1629	bool
1630
1631config X86_PMEM_LEGACY
1632	tristate "Support non-standard NVDIMMs and ADR protected memory"
1633	depends on PHYS_ADDR_T_64BIT
1634	depends on BLK_DEV
1635	select X86_PMEM_LEGACY_DEVICE
1636	select LIBNVDIMM
1637	help
1638	  Treat memory marked using the non-standard e820 type of 12 as used
1639	  by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1640	  The kernel will offer these regions to the 'pmem' driver so
1641	  they can be used for persistent storage.
1642
1643	  Say Y if unsure.
1644
1645config HIGHPTE
1646	bool "Allocate 3rd-level pagetables from highmem"
1647	depends on HIGHMEM
1648	---help---
1649	  The VM uses one page table entry for each page of physical memory.
1650	  For systems with a lot of RAM, this can be wasteful of precious
1651	  low memory.  Setting this option will put user-space page table
1652	  entries in high memory.
1653
1654config X86_CHECK_BIOS_CORRUPTION
1655	bool "Check for low memory corruption"
1656	---help---
1657	  Periodically check for memory corruption in low memory, which
1658	  is suspected to be caused by BIOS.  Even when enabled in the
1659	  configuration, it is disabled at runtime.  Enable it by
1660	  setting "memory_corruption_check=1" on the kernel command
1661	  line.  By default it scans the low 64k of memory every 60
1662	  seconds; see the memory_corruption_check_size and
1663	  memory_corruption_check_period parameters in
1664	  Documentation/admin-guide/kernel-parameters.rst to adjust this.
1665
1666	  When enabled with the default parameters, this option has
1667	  almost no overhead, as it reserves a relatively small amount
1668	  of memory and scans it infrequently.  It both detects corruption
1669	  and prevents it from affecting the running system.
1670
1671	  It is, however, intended as a diagnostic tool; if repeatable
1672	  BIOS-originated corruption always affects the same memory,
1673	  you can use memmap= to prevent the kernel from using that
1674	  memory.
1675
1676config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1677	bool "Set the default setting of memory_corruption_check"
1678	depends on X86_CHECK_BIOS_CORRUPTION
1679	default y
1680	---help---
1681	  Set whether the default state of memory_corruption_check is
1682	  on or off.
1683
1684config X86_RESERVE_LOW
1685	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1686	default 64
1687	range 4 640
1688	---help---
1689	  Specify the amount of low memory to reserve for the BIOS.
1690
1691	  The first page contains BIOS data structures that the kernel
1692	  must not use, so that page must always be reserved.
1693
1694	  By default we reserve the first 64K of physical RAM, as a
1695	  number of BIOSes are known to corrupt that memory range
1696	  during events such as suspend/resume or monitor cable
1697	  insertion, so it must not be used by the kernel.
1698
1699	  You can set this to 4 if you are absolutely sure that you
1700	  trust the BIOS to get all its memory reservations and usages
1701	  right.  If you know your BIOS have problems beyond the
1702	  default 64K area, you can set this to 640 to avoid using the
1703	  entire low memory range.
1704
1705	  If you have doubts about the BIOS (e.g. suspend/resume does
1706	  not work or there's kernel crashes after certain hardware
1707	  hotplug events) then you might want to enable
1708	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1709	  typical corruption patterns.
1710
1711	  Leave this to the default value of 64 if you are unsure.
1712
1713config MATH_EMULATION
1714	bool
1715	depends on MODIFY_LDT_SYSCALL
1716	prompt "Math emulation" if X86_32
1717	---help---
1718	  Linux can emulate a math coprocessor (used for floating point
1719	  operations) if you don't have one. 486DX and Pentium processors have
1720	  a math coprocessor built in, 486SX and 386 do not, unless you added
1721	  a 487DX or 387, respectively. (The messages during boot time can
1722	  give you some hints here ["man dmesg"].) Everyone needs either a
1723	  coprocessor or this emulation.
1724
1725	  If you don't have a math coprocessor, you need to say Y here; if you
1726	  say Y here even though you have a coprocessor, the coprocessor will
1727	  be used nevertheless. (This behavior can be changed with the kernel
1728	  command line option "no387", which comes handy if your coprocessor
1729	  is broken. Try "man bootparam" or see the documentation of your boot
1730	  loader (lilo or loadlin) about how to pass options to the kernel at
1731	  boot time.) This means that it is a good idea to say Y here if you
1732	  intend to use this kernel on different machines.
1733
1734	  More information about the internals of the Linux math coprocessor
1735	  emulation can be found in <file:arch/x86/math-emu/README>.
1736
1737	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1738	  kernel, it won't hurt.
1739
1740config MTRR
1741	def_bool y
1742	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1743	---help---
1744	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1745	  the Memory Type Range Registers (MTRRs) may be used to control
1746	  processor access to memory ranges. This is most useful if you have
1747	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1748	  allows bus write transfers to be combined into a larger transfer
1749	  before bursting over the PCI/AGP bus. This can increase performance
1750	  of image write operations 2.5 times or more. Saying Y here creates a
1751	  /proc/mtrr file which may be used to manipulate your processor's
1752	  MTRRs. Typically the X server should use this.
1753
1754	  This code has a reasonably generic interface so that similar
1755	  control registers on other processors can be easily supported
1756	  as well:
1757
1758	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1759	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1760	  these, the ARRs are used to emulate the MTRRs.
1761	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1762	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1763	  write-combining. All of these processors are supported by this code
1764	  and it makes sense to say Y here if you have one of them.
1765
1766	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1767	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1768	  can lead to all sorts of problems, so it's good to say Y here.
1769
1770	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1771	  just add about 9 KB to your kernel.
1772
1773	  See <file:Documentation/x86/mtrr.txt> for more information.
1774
1775config MTRR_SANITIZER
1776	def_bool y
1777	prompt "MTRR cleanup support"
1778	depends on MTRR
1779	---help---
1780	  Convert MTRR layout from continuous to discrete, so X drivers can
1781	  add writeback entries.
1782
1783	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1784	  The largest mtrr entry size for a continuous block can be set with
1785	  mtrr_chunk_size.
1786
1787	  If unsure, say Y.
1788
1789config MTRR_SANITIZER_ENABLE_DEFAULT
1790	int "MTRR cleanup enable value (0-1)"
1791	range 0 1
1792	default "0"
1793	depends on MTRR_SANITIZER
1794	---help---
1795	  Enable mtrr cleanup default value
1796
1797config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1798	int "MTRR cleanup spare reg num (0-7)"
1799	range 0 7
1800	default "1"
1801	depends on MTRR_SANITIZER
1802	---help---
1803	  mtrr cleanup spare entries default, it can be changed via
1804	  mtrr_spare_reg_nr=N on the kernel command line.
1805
1806config X86_PAT
1807	def_bool y
1808	prompt "x86 PAT support" if EXPERT
1809	depends on MTRR
1810	---help---
1811	  Use PAT attributes to setup page level cache control.
1812
1813	  PATs are the modern equivalents of MTRRs and are much more
1814	  flexible than MTRRs.
1815
1816	  Say N here if you see bootup problems (boot crash, boot hang,
1817	  spontaneous reboots) or a non-working video driver.
1818
1819	  If unsure, say Y.
1820
1821config ARCH_USES_PG_UNCACHED
1822	def_bool y
1823	depends on X86_PAT
1824
1825config ARCH_RANDOM
1826	def_bool y
1827	prompt "x86 architectural random number generator" if EXPERT
1828	---help---
1829	  Enable the x86 architectural RDRAND instruction
1830	  (Intel Bull Mountain technology) to generate random numbers.
1831	  If supported, this is a high bandwidth, cryptographically
1832	  secure hardware random number generator.
1833
1834config X86_SMAP
1835	def_bool y
1836	prompt "Supervisor Mode Access Prevention" if EXPERT
1837	---help---
1838	  Supervisor Mode Access Prevention (SMAP) is a security
1839	  feature in newer Intel processors.  There is a small
1840	  performance cost if this enabled and turned on; there is
1841	  also a small increase in the kernel size if this is enabled.
1842
1843	  If unsure, say Y.
1844
1845config X86_INTEL_UMIP
1846	def_bool y
1847	depends on CPU_SUP_INTEL
1848	prompt "Intel User Mode Instruction Prevention" if EXPERT
1849	---help---
1850	  The User Mode Instruction Prevention (UMIP) is a security
1851	  feature in newer Intel processors. If enabled, a general
1852	  protection fault is issued if the SGDT, SLDT, SIDT, SMSW
1853	  or STR instructions are executed in user mode. These instructions
1854	  unnecessarily expose information about the hardware state.
1855
1856	  The vast majority of applications do not use these instructions.
1857	  For the very few that do, software emulation is provided in
1858	  specific cases in protected and virtual-8086 modes. Emulated
1859	  results are dummy.
1860
1861config X86_INTEL_MPX
1862	prompt "Intel MPX (Memory Protection Extensions)"
1863	def_bool n
1864	# Note: only available in 64-bit mode due to VMA flags shortage
1865	depends on CPU_SUP_INTEL && X86_64
1866	select ARCH_USES_HIGH_VMA_FLAGS
1867	---help---
1868	  MPX provides hardware features that can be used in
1869	  conjunction with compiler-instrumented code to check
1870	  memory references.  It is designed to detect buffer
1871	  overflow or underflow bugs.
1872
1873	  This option enables running applications which are
1874	  instrumented or otherwise use MPX.  It does not use MPX
1875	  itself inside the kernel or to protect the kernel
1876	  against bad memory references.
1877
1878	  Enabling this option will make the kernel larger:
1879	  ~8k of kernel text and 36 bytes of data on a 64-bit
1880	  defconfig.  It adds a long to the 'mm_struct' which
1881	  will increase the kernel memory overhead of each
1882	  process and adds some branches to paths used during
1883	  exec() and munmap().
1884
1885	  For details, see Documentation/x86/intel_mpx.txt
1886
1887	  If unsure, say N.
1888
1889config X86_INTEL_MEMORY_PROTECTION_KEYS
1890	prompt "Intel Memory Protection Keys"
1891	def_bool y
1892	# Note: only available in 64-bit mode
1893	depends on CPU_SUP_INTEL && X86_64
1894	select ARCH_USES_HIGH_VMA_FLAGS
1895	select ARCH_HAS_PKEYS
1896	---help---
1897	  Memory Protection Keys provides a mechanism for enforcing
1898	  page-based protections, but without requiring modification of the
1899	  page tables when an application changes protection domains.
1900
1901	  For details, see Documentation/x86/protection-keys.txt
1902
1903	  If unsure, say y.
1904
1905choice
1906	prompt "TSX enable mode"
1907	depends on CPU_SUP_INTEL
1908	default X86_INTEL_TSX_MODE_OFF
1909	help
1910	  Intel's TSX (Transactional Synchronization Extensions) feature
1911	  allows to optimize locking protocols through lock elision which
1912	  can lead to a noticeable performance boost.
1913
1914	  On the other hand it has been shown that TSX can be exploited
1915	  to form side channel attacks (e.g. TAA) and chances are there
1916	  will be more of those attacks discovered in the future.
1917
1918	  Therefore TSX is not enabled by default (aka tsx=off). An admin
1919	  might override this decision by tsx=on the command line parameter.
1920	  Even with TSX enabled, the kernel will attempt to enable the best
1921	  possible TAA mitigation setting depending on the microcode available
1922	  for the particular machine.
1923
1924	  This option allows to set the default tsx mode between tsx=on, =off
1925	  and =auto. See Documentation/admin-guide/kernel-parameters.txt for more
1926	  details.
1927
1928	  Say off if not sure, auto if TSX is in use but it should be used on safe
1929	  platforms or on if TSX is in use and the security aspect of tsx is not
1930	  relevant.
1931
1932config X86_INTEL_TSX_MODE_OFF
1933	bool "off"
1934	help
1935	  TSX is disabled if possible - equals to tsx=off command line parameter.
1936
1937config X86_INTEL_TSX_MODE_ON
1938	bool "on"
1939	help
1940	  TSX is always enabled on TSX capable HW - equals the tsx=on command
1941	  line parameter.
1942
1943config X86_INTEL_TSX_MODE_AUTO
1944	bool "auto"
1945	help
1946	  TSX is enabled on TSX capable HW that is believed to be safe against
1947	  side channel attacks- equals the tsx=auto command line parameter.
1948endchoice
1949
1950config EFI
1951	bool "EFI runtime service support"
1952	depends on ACPI
1953	select UCS2_STRING
1954	select EFI_RUNTIME_WRAPPERS
1955	---help---
1956	  This enables the kernel to use EFI runtime services that are
1957	  available (such as the EFI variable services).
1958
1959	  This option is only useful on systems that have EFI firmware.
1960	  In addition, you should use the latest ELILO loader available
1961	  at <http://elilo.sourceforge.net> in order to take advantage
1962	  of EFI runtime services. However, even with this option, the
1963	  resultant kernel should continue to boot on existing non-EFI
1964	  platforms.
1965
1966config EFI_STUB
1967       bool "EFI stub support"
1968       depends on EFI && !X86_USE_3DNOW
1969       select RELOCATABLE
1970       ---help---
1971          This kernel feature allows a bzImage to be loaded directly
1972	  by EFI firmware without the use of a bootloader.
1973
1974	  See Documentation/efi-stub.txt for more information.
1975
1976config EFI_MIXED
1977	bool "EFI mixed-mode support"
1978	depends on EFI_STUB && X86_64
1979	---help---
1980	   Enabling this feature allows a 64-bit kernel to be booted
1981	   on a 32-bit firmware, provided that your CPU supports 64-bit
1982	   mode.
1983
1984	   Note that it is not possible to boot a mixed-mode enabled
1985	   kernel via the EFI boot stub - a bootloader that supports
1986	   the EFI handover protocol must be used.
1987
1988	   If unsure, say N.
1989
1990config SECCOMP
1991	def_bool y
1992	prompt "Enable seccomp to safely compute untrusted bytecode"
1993	---help---
1994	  This kernel feature is useful for number crunching applications
1995	  that may need to compute untrusted bytecode during their
1996	  execution. By using pipes or other transports made available to
1997	  the process as file descriptors supporting the read/write
1998	  syscalls, it's possible to isolate those applications in
1999	  their own address space using seccomp. Once seccomp is
2000	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
2001	  and the task is only allowed to execute a few safe syscalls
2002	  defined by each seccomp mode.
2003
2004	  If unsure, say Y. Only embedded should say N here.
2005
2006source kernel/Kconfig.hz
2007
2008config KEXEC
2009	bool "kexec system call"
2010	select KEXEC_CORE
2011	---help---
2012	  kexec is a system call that implements the ability to shutdown your
2013	  current kernel, and to start another kernel.  It is like a reboot
2014	  but it is independent of the system firmware.   And like a reboot
2015	  you can start any kernel with it, not just Linux.
2016
2017	  The name comes from the similarity to the exec system call.
2018
2019	  It is an ongoing process to be certain the hardware in a machine
2020	  is properly shutdown, so do not be surprised if this code does not
2021	  initially work for you.  As of this writing the exact hardware
2022	  interface is strongly in flux, so no good recommendation can be
2023	  made.
2024
2025config KEXEC_FILE
2026	bool "kexec file based system call"
2027	select KEXEC_CORE
2028	select BUILD_BIN2C
2029	depends on X86_64
2030	depends on CRYPTO=y
2031	depends on CRYPTO_SHA256=y
2032	---help---
2033	  This is new version of kexec system call. This system call is
2034	  file based and takes file descriptors as system call argument
2035	  for kernel and initramfs as opposed to list of segments as
2036	  accepted by previous system call.
2037
2038config ARCH_HAS_KEXEC_PURGATORY
2039	def_bool KEXEC_FILE
2040
2041config KEXEC_VERIFY_SIG
2042	bool "Verify kernel signature during kexec_file_load() syscall"
2043	depends on KEXEC_FILE
2044	---help---
2045	  This option makes kernel signature verification mandatory for
2046	  the kexec_file_load() syscall.
2047
2048	  In addition to that option, you need to enable signature
2049	  verification for the corresponding kernel image type being
2050	  loaded in order for this to work.
2051
2052config KEXEC_BZIMAGE_VERIFY_SIG
2053	bool "Enable bzImage signature verification support"
2054	depends on KEXEC_VERIFY_SIG
2055	depends on SIGNED_PE_FILE_VERIFICATION
2056	select SYSTEM_TRUSTED_KEYRING
2057	---help---
2058	  Enable bzImage signature verification support.
2059
2060config CRASH_DUMP
2061	bool "kernel crash dumps"
2062	depends on X86_64 || (X86_32 && HIGHMEM)
2063	---help---
2064	  Generate crash dump after being started by kexec.
2065	  This should be normally only set in special crash dump kernels
2066	  which are loaded in the main kernel with kexec-tools into
2067	  a specially reserved region and then later executed after
2068	  a crash by kdump/kexec. The crash dump kernel must be compiled
2069	  to a memory address not used by the main kernel or BIOS using
2070	  PHYSICAL_START, or it must be built as a relocatable image
2071	  (CONFIG_RELOCATABLE=y).
2072	  For more details see Documentation/kdump/kdump.txt
2073
2074config KEXEC_JUMP
2075	bool "kexec jump"
2076	depends on KEXEC && HIBERNATION
2077	---help---
2078	  Jump between original kernel and kexeced kernel and invoke
2079	  code in physical address mode via KEXEC
2080
2081config PHYSICAL_START
2082	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
2083	default "0x1000000"
2084	---help---
2085	  This gives the physical address where the kernel is loaded.
2086
2087	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
2088	  bzImage will decompress itself to above physical address and
2089	  run from there. Otherwise, bzImage will run from the address where
2090	  it has been loaded by the boot loader and will ignore above physical
2091	  address.
2092
2093	  In normal kdump cases one does not have to set/change this option
2094	  as now bzImage can be compiled as a completely relocatable image
2095	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
2096	  address. This option is mainly useful for the folks who don't want
2097	  to use a bzImage for capturing the crash dump and want to use a
2098	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
2099	  to be specifically compiled to run from a specific memory area
2100	  (normally a reserved region) and this option comes handy.
2101
2102	  So if you are using bzImage for capturing the crash dump,
2103	  leave the value here unchanged to 0x1000000 and set
2104	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
2105	  for capturing the crash dump change this value to start of
2106	  the reserved region.  In other words, it can be set based on
2107	  the "X" value as specified in the "crashkernel=YM@XM"
2108	  command line boot parameter passed to the panic-ed
2109	  kernel. Please take a look at Documentation/kdump/kdump.txt
2110	  for more details about crash dumps.
2111
2112	  Usage of bzImage for capturing the crash dump is recommended as
2113	  one does not have to build two kernels. Same kernel can be used
2114	  as production kernel and capture kernel. Above option should have
2115	  gone away after relocatable bzImage support is introduced. But it
2116	  is present because there are users out there who continue to use
2117	  vmlinux for dump capture. This option should go away down the
2118	  line.
2119
2120	  Don't change this unless you know what you are doing.
2121
2122config RELOCATABLE
2123	bool "Build a relocatable kernel"
2124	default y
2125	---help---
2126	  This builds a kernel image that retains relocation information
2127	  so it can be loaded someplace besides the default 1MB.
2128	  The relocations tend to make the kernel binary about 10% larger,
2129	  but are discarded at runtime.
2130
2131	  One use is for the kexec on panic case where the recovery kernel
2132	  must live at a different physical address than the primary
2133	  kernel.
2134
2135	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
2136	  it has been loaded at and the compile time physical address
2137	  (CONFIG_PHYSICAL_START) is used as the minimum location.
2138
2139config RANDOMIZE_BASE
2140	bool "Randomize the address of the kernel image (KASLR)"
2141	depends on RELOCATABLE
2142	default y
2143	---help---
2144	  In support of Kernel Address Space Layout Randomization (KASLR),
2145	  this randomizes the physical address at which the kernel image
2146	  is decompressed and the virtual address where the kernel
2147	  image is mapped, as a security feature that deters exploit
2148	  attempts relying on knowledge of the location of kernel
2149	  code internals.
2150
2151	  On 64-bit, the kernel physical and virtual addresses are
2152	  randomized separately. The physical address will be anywhere
2153	  between 16MB and the top of physical memory (up to 64TB). The
2154	  virtual address will be randomized from 16MB up to 1GB (9 bits
2155	  of entropy). Note that this also reduces the memory space
2156	  available to kernel modules from 1.5GB to 1GB.
2157
2158	  On 32-bit, the kernel physical and virtual addresses are
2159	  randomized together. They will be randomized from 16MB up to
2160	  512MB (8 bits of entropy).
2161
2162	  Entropy is generated using the RDRAND instruction if it is
2163	  supported. If RDTSC is supported, its value is mixed into
2164	  the entropy pool as well. If neither RDRAND nor RDTSC are
2165	  supported, then entropy is read from the i8254 timer. The
2166	  usable entropy is limited by the kernel being built using
2167	  2GB addressing, and that PHYSICAL_ALIGN must be at a
2168	  minimum of 2MB. As a result, only 10 bits of entropy are
2169	  theoretically possible, but the implementations are further
2170	  limited due to memory layouts.
2171
2172	  If unsure, say Y.
2173
2174# Relocation on x86 needs some additional build support
2175config X86_NEED_RELOCS
2176	def_bool y
2177	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
2178
2179config PHYSICAL_ALIGN
2180	hex "Alignment value to which kernel should be aligned"
2181	default "0x200000"
2182	range 0x2000 0x1000000 if X86_32
2183	range 0x200000 0x1000000 if X86_64
2184	---help---
2185	  This value puts the alignment restrictions on physical address
2186	  where kernel is loaded and run from. Kernel is compiled for an
2187	  address which meets above alignment restriction.
2188
2189	  If bootloader loads the kernel at a non-aligned address and
2190	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2191	  address aligned to above value and run from there.
2192
2193	  If bootloader loads the kernel at a non-aligned address and
2194	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2195	  load address and decompress itself to the address it has been
2196	  compiled for and run from there. The address for which kernel is
2197	  compiled already meets above alignment restrictions. Hence the
2198	  end result is that kernel runs from a physical address meeting
2199	  above alignment restrictions.
2200
2201	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
2202	  this value must be a multiple of 0x200000.
2203
2204	  Don't change this unless you know what you are doing.
2205
2206config DYNAMIC_MEMORY_LAYOUT
2207	bool
2208	---help---
2209	  This option makes base addresses of vmalloc and vmemmap as well as
2210	  __PAGE_OFFSET movable during boot.
2211
2212config RANDOMIZE_MEMORY
2213	bool "Randomize the kernel memory sections"
2214	depends on X86_64
2215	depends on RANDOMIZE_BASE
2216	select DYNAMIC_MEMORY_LAYOUT
2217	default RANDOMIZE_BASE
2218	---help---
2219	   Randomizes the base virtual address of kernel memory sections
2220	   (physical memory mapping, vmalloc & vmemmap). This security feature
2221	   makes exploits relying on predictable memory locations less reliable.
2222
2223	   The order of allocations remains unchanged. Entropy is generated in
2224	   the same way as RANDOMIZE_BASE. Current implementation in the optimal
2225	   configuration have in average 30,000 different possible virtual
2226	   addresses for each memory section.
2227
2228	   If unsure, say Y.
2229
2230config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2231	hex "Physical memory mapping padding" if EXPERT
2232	depends on RANDOMIZE_MEMORY
2233	default "0xa" if MEMORY_HOTPLUG
2234	default "0x0"
2235	range 0x1 0x40 if MEMORY_HOTPLUG
2236	range 0x0 0x40
2237	---help---
2238	   Define the padding in terabytes added to the existing physical
2239	   memory size during kernel memory randomization. It is useful
2240	   for memory hotplug support but reduces the entropy available for
2241	   address randomization.
2242
2243	   If unsure, leave at the default value.
2244
2245config HOTPLUG_CPU
2246	def_bool y
2247	depends on SMP
2248
2249config BOOTPARAM_HOTPLUG_CPU0
2250	bool "Set default setting of cpu0_hotpluggable"
2251	default n
2252	depends on HOTPLUG_CPU
2253	---help---
2254	  Set whether default state of cpu0_hotpluggable is on or off.
2255
2256	  Say Y here to enable CPU0 hotplug by default. If this switch
2257	  is turned on, there is no need to give cpu0_hotplug kernel
2258	  parameter and the CPU0 hotplug feature is enabled by default.
2259
2260	  Please note: there are two known CPU0 dependencies if you want
2261	  to enable the CPU0 hotplug feature either by this switch or by
2262	  cpu0_hotplug kernel parameter.
2263
2264	  First, resume from hibernate or suspend always starts from CPU0.
2265	  So hibernate and suspend are prevented if CPU0 is offline.
2266
2267	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2268	  offline if any interrupt can not migrate out of CPU0. There may
2269	  be other CPU0 dependencies.
2270
2271	  Please make sure the dependencies are under your control before
2272	  you enable this feature.
2273
2274	  Say N if you don't want to enable CPU0 hotplug feature by default.
2275	  You still can enable the CPU0 hotplug feature at boot by kernel
2276	  parameter cpu0_hotplug.
2277
2278config DEBUG_HOTPLUG_CPU0
2279	def_bool n
2280	prompt "Debug CPU0 hotplug"
2281	depends on HOTPLUG_CPU
2282	---help---
2283	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2284	  soon as possible and boots up userspace with CPU0 offlined. User
2285	  can online CPU0 back after boot time.
2286
2287	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
2288	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2289	  compilation or giving cpu0_hotplug kernel parameter at boot.
2290
2291	  If unsure, say N.
2292
2293config COMPAT_VDSO
2294	def_bool n
2295	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2296	depends on COMPAT_32
2297	---help---
2298	  Certain buggy versions of glibc will crash if they are
2299	  presented with a 32-bit vDSO that is not mapped at the address
2300	  indicated in its segment table.
2301
2302	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2303	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2304	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2305	  the only released version with the bug, but OpenSUSE 9
2306	  contains a buggy "glibc 2.3.2".
2307
2308	  The symptom of the bug is that everything crashes on startup, saying:
2309	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2310
2311	  Saying Y here changes the default value of the vdso32 boot
2312	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
2313	  This works around the glibc bug but hurts performance.
2314
2315	  If unsure, say N: if you are compiling your own kernel, you
2316	  are unlikely to be using a buggy version of glibc.
2317
2318choice
2319	prompt "vsyscall table for legacy applications"
2320	depends on X86_64
2321	default LEGACY_VSYSCALL_EMULATE
2322	help
2323	  Legacy user code that does not know how to find the vDSO expects
2324	  to be able to issue three syscalls by calling fixed addresses in
2325	  kernel space. Since this location is not randomized with ASLR,
2326	  it can be used to assist security vulnerability exploitation.
2327
2328	  This setting can be changed at boot time via the kernel command
2329	  line parameter vsyscall=[emulate|none].
2330
2331	  On a system with recent enough glibc (2.14 or newer) and no
2332	  static binaries, you can say None without a performance penalty
2333	  to improve security.
2334
2335	  If unsure, select "Emulate".
2336
2337	config LEGACY_VSYSCALL_EMULATE
2338		bool "Emulate"
2339		help
2340		  The kernel traps and emulates calls into the fixed
2341		  vsyscall address mapping. This makes the mapping
2342		  non-executable, but it still contains known contents,
2343		  which could be used in certain rare security vulnerability
2344		  exploits. This configuration is recommended when userspace
2345		  still uses the vsyscall area.
2346
2347	config LEGACY_VSYSCALL_NONE
2348		bool "None"
2349		help
2350		  There will be no vsyscall mapping at all. This will
2351		  eliminate any risk of ASLR bypass due to the vsyscall
2352		  fixed address mapping. Attempts to use the vsyscalls
2353		  will be reported to dmesg, so that either old or
2354		  malicious userspace programs can be identified.
2355
2356endchoice
2357
2358config CMDLINE_BOOL
2359	bool "Built-in kernel command line"
2360	---help---
2361	  Allow for specifying boot arguments to the kernel at
2362	  build time.  On some systems (e.g. embedded ones), it is
2363	  necessary or convenient to provide some or all of the
2364	  kernel boot arguments with the kernel itself (that is,
2365	  to not rely on the boot loader to provide them.)
2366
2367	  To compile command line arguments into the kernel,
2368	  set this option to 'Y', then fill in the
2369	  boot arguments in CONFIG_CMDLINE.
2370
2371	  Systems with fully functional boot loaders (i.e. non-embedded)
2372	  should leave this option set to 'N'.
2373
2374config CMDLINE
2375	string "Built-in kernel command string"
2376	depends on CMDLINE_BOOL
2377	default ""
2378	---help---
2379	  Enter arguments here that should be compiled into the kernel
2380	  image and used at boot time.  If the boot loader provides a
2381	  command line at boot time, it is appended to this string to
2382	  form the full kernel command line, when the system boots.
2383
2384	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2385	  change this behavior.
2386
2387	  In most cases, the command line (whether built-in or provided
2388	  by the boot loader) should specify the device for the root
2389	  file system.
2390
2391config CMDLINE_OVERRIDE
2392	bool "Built-in command line overrides boot loader arguments"
2393	depends on CMDLINE_BOOL
2394	---help---
2395	  Set this option to 'Y' to have the kernel ignore the boot loader
2396	  command line, and use ONLY the built-in command line.
2397
2398	  This is used to work around broken boot loaders.  This should
2399	  be set to 'N' under normal conditions.
2400
2401config MODIFY_LDT_SYSCALL
2402	bool "Enable the LDT (local descriptor table)" if EXPERT
2403	default y
2404	---help---
2405	  Linux can allow user programs to install a per-process x86
2406	  Local Descriptor Table (LDT) using the modify_ldt(2) system
2407	  call.  This is required to run 16-bit or segmented code such as
2408	  DOSEMU or some Wine programs.  It is also used by some very old
2409	  threading libraries.
2410
2411	  Enabling this feature adds a small amount of overhead to
2412	  context switches and increases the low-level kernel attack
2413	  surface.  Disabling it removes the modify_ldt(2) system call.
2414
2415	  Saying 'N' here may make sense for embedded or server kernels.
2416
2417source "kernel/livepatch/Kconfig"
2418
2419endmenu
2420
2421config ARCH_HAS_ADD_PAGES
2422	def_bool y
2423	depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
2424
2425config ARCH_ENABLE_MEMORY_HOTPLUG
2426	def_bool y
2427	depends on X86_64 || (X86_32 && HIGHMEM)
2428
2429config ARCH_ENABLE_MEMORY_HOTREMOVE
2430	def_bool y
2431	depends on MEMORY_HOTPLUG
2432
2433config USE_PERCPU_NUMA_NODE_ID
2434	def_bool y
2435	depends on NUMA
2436
2437config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2438	def_bool y
2439	depends on X86_64 || X86_PAE
2440
2441config ARCH_ENABLE_HUGEPAGE_MIGRATION
2442	def_bool y
2443	depends on X86_64 && HUGETLB_PAGE && MIGRATION
2444
2445config ARCH_ENABLE_THP_MIGRATION
2446	def_bool y
2447	depends on X86_64 && TRANSPARENT_HUGEPAGE
2448
2449menu "Power management and ACPI options"
2450
2451config ARCH_HIBERNATION_HEADER
2452	def_bool y
2453	depends on X86_64 && HIBERNATION
2454
2455source "kernel/power/Kconfig"
2456
2457source "drivers/acpi/Kconfig"
2458
2459source "drivers/sfi/Kconfig"
2460
2461config X86_APM_BOOT
2462	def_bool y
2463	depends on APM
2464
2465menuconfig APM
2466	tristate "APM (Advanced Power Management) BIOS support"
2467	depends on X86_32 && PM_SLEEP
2468	---help---
2469	  APM is a BIOS specification for saving power using several different
2470	  techniques. This is mostly useful for battery powered laptops with
2471	  APM compliant BIOSes. If you say Y here, the system time will be
2472	  reset after a RESUME operation, the /proc/apm device will provide
2473	  battery status information, and user-space programs will receive
2474	  notification of APM "events" (e.g. battery status change).
2475
2476	  If you select "Y" here, you can disable actual use of the APM
2477	  BIOS by passing the "apm=off" option to the kernel at boot time.
2478
2479	  Note that the APM support is almost completely disabled for
2480	  machines with more than one CPU.
2481
2482	  In order to use APM, you will need supporting software. For location
2483	  and more information, read <file:Documentation/power/apm-acpi.txt>
2484	  and the Battery Powered Linux mini-HOWTO, available from
2485	  <http://www.tldp.org/docs.html#howto>.
2486
2487	  This driver does not spin down disk drives (see the hdparm(8)
2488	  manpage ("man 8 hdparm") for that), and it doesn't turn off
2489	  VESA-compliant "green" monitors.
2490
2491	  This driver does not support the TI 4000M TravelMate and the ACER
2492	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
2493	  desktop machines also don't have compliant BIOSes, and this driver
2494	  may cause those machines to panic during the boot phase.
2495
2496	  Generally, if you don't have a battery in your machine, there isn't
2497	  much point in using this driver and you should say N. If you get
2498	  random kernel OOPSes or reboots that don't seem to be related to
2499	  anything, try disabling/enabling this option (or disabling/enabling
2500	  APM in your BIOS).
2501
2502	  Some other things you should try when experiencing seemingly random,
2503	  "weird" problems:
2504
2505	  1) make sure that you have enough swap space and that it is
2506	  enabled.
2507	  2) pass the "no-hlt" option to the kernel
2508	  3) switch on floating point emulation in the kernel and pass
2509	  the "no387" option to the kernel
2510	  4) pass the "floppy=nodma" option to the kernel
2511	  5) pass the "mem=4M" option to the kernel (thereby disabling
2512	  all but the first 4 MB of RAM)
2513	  6) make sure that the CPU is not over clocked.
2514	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2515	  8) disable the cache from your BIOS settings
2516	  9) install a fan for the video card or exchange video RAM
2517	  10) install a better fan for the CPU
2518	  11) exchange RAM chips
2519	  12) exchange the motherboard.
2520
2521	  To compile this driver as a module, choose M here: the
2522	  module will be called apm.
2523
2524if APM
2525
2526config APM_IGNORE_USER_SUSPEND
2527	bool "Ignore USER SUSPEND"
2528	---help---
2529	  This option will ignore USER SUSPEND requests. On machines with a
2530	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
2531	  series notebooks, it is necessary to say Y because of a BIOS bug.
2532
2533config APM_DO_ENABLE
2534	bool "Enable PM at boot time"
2535	---help---
2536	  Enable APM features at boot time. From page 36 of the APM BIOS
2537	  specification: "When disabled, the APM BIOS does not automatically
2538	  power manage devices, enter the Standby State, enter the Suspend
2539	  State, or take power saving steps in response to CPU Idle calls."
2540	  This driver will make CPU Idle calls when Linux is idle (unless this
2541	  feature is turned off -- see "Do CPU IDLE calls", below). This
2542	  should always save battery power, but more complicated APM features
2543	  will be dependent on your BIOS implementation. You may need to turn
2544	  this option off if your computer hangs at boot time when using APM
2545	  support, or if it beeps continuously instead of suspending. Turn
2546	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2547	  T400CDT. This is off by default since most machines do fine without
2548	  this feature.
2549
2550config APM_CPU_IDLE
2551	depends on CPU_IDLE
2552	bool "Make CPU Idle calls when idle"
2553	---help---
2554	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2555	  On some machines, this can activate improved power savings, such as
2556	  a slowed CPU clock rate, when the machine is idle. These idle calls
2557	  are made after the idle loop has run for some length of time (e.g.,
2558	  333 mS). On some machines, this will cause a hang at boot time or
2559	  whenever the CPU becomes idle. (On machines with more than one CPU,
2560	  this option does nothing.)
2561
2562config APM_DISPLAY_BLANK
2563	bool "Enable console blanking using APM"
2564	---help---
2565	  Enable console blanking using the APM. Some laptops can use this to
2566	  turn off the LCD backlight when the screen blanker of the Linux
2567	  virtual console blanks the screen. Note that this is only used by
2568	  the virtual console screen blanker, and won't turn off the backlight
2569	  when using the X Window system. This also doesn't have anything to
2570	  do with your VESA-compliant power-saving monitor. Further, this
2571	  option doesn't work for all laptops -- it might not turn off your
2572	  backlight at all, or it might print a lot of errors to the console,
2573	  especially if you are using gpm.
2574
2575config APM_ALLOW_INTS
2576	bool "Allow interrupts during APM BIOS calls"
2577	---help---
2578	  Normally we disable external interrupts while we are making calls to
2579	  the APM BIOS as a measure to lessen the effects of a badly behaving
2580	  BIOS implementation.  The BIOS should reenable interrupts if it
2581	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2582	  many of the newer IBM Thinkpads.  If you experience hangs when you
2583	  suspend, try setting this to Y.  Otherwise, say N.
2584
2585endif # APM
2586
2587source "drivers/cpufreq/Kconfig"
2588
2589source "drivers/cpuidle/Kconfig"
2590
2591source "drivers/idle/Kconfig"
2592
2593endmenu
2594
2595
2596menu "Bus options (PCI etc.)"
2597
2598config PCI
2599	bool "PCI support"
2600	default y
2601	---help---
2602	  Find out whether you have a PCI motherboard. PCI is the name of a
2603	  bus system, i.e. the way the CPU talks to the other stuff inside
2604	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2605	  VESA. If you have PCI, say Y, otherwise N.
2606
2607choice
2608	prompt "PCI access mode"
2609	depends on X86_32 && PCI
2610	default PCI_GOANY
2611	---help---
2612	  On PCI systems, the BIOS can be used to detect the PCI devices and
2613	  determine their configuration. However, some old PCI motherboards
2614	  have BIOS bugs and may crash if this is done. Also, some embedded
2615	  PCI-based systems don't have any BIOS at all. Linux can also try to
2616	  detect the PCI hardware directly without using the BIOS.
2617
2618	  With this option, you can specify how Linux should detect the
2619	  PCI devices. If you choose "BIOS", the BIOS will be used,
2620	  if you choose "Direct", the BIOS won't be used, and if you
2621	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2622	  If you choose "Any", the kernel will try MMCONFIG, then the
2623	  direct access method and falls back to the BIOS if that doesn't
2624	  work. If unsure, go with the default, which is "Any".
2625
2626config PCI_GOBIOS
2627	bool "BIOS"
2628
2629config PCI_GOMMCONFIG
2630	bool "MMConfig"
2631
2632config PCI_GODIRECT
2633	bool "Direct"
2634
2635config PCI_GOOLPC
2636	bool "OLPC XO-1"
2637	depends on OLPC
2638
2639config PCI_GOANY
2640	bool "Any"
2641
2642endchoice
2643
2644config PCI_BIOS
2645	def_bool y
2646	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2647
2648# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2649config PCI_DIRECT
2650	def_bool y
2651	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2652
2653config PCI_MMCONFIG
2654	bool "Support mmconfig PCI config space access" if X86_64
2655	default y
2656	depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
2657	depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
2658
2659config PCI_OLPC
2660	def_bool y
2661	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2662
2663config PCI_XEN
2664	def_bool y
2665	depends on PCI && XEN
2666	select SWIOTLB_XEN
2667
2668config PCI_DOMAINS
2669	def_bool y
2670	depends on PCI
2671
2672config MMCONF_FAM10H
2673	def_bool y
2674	depends on X86_64 && PCI_MMCONFIG && ACPI
2675
2676config PCI_CNB20LE_QUIRK
2677	bool "Read CNB20LE Host Bridge Windows" if EXPERT
2678	depends on PCI
2679	help
2680	  Read the PCI windows out of the CNB20LE host bridge. This allows
2681	  PCI hotplug to work on systems with the CNB20LE chipset which do
2682	  not have ACPI.
2683
2684	  There's no public spec for this chipset, and this functionality
2685	  is known to be incomplete.
2686
2687	  You should say N unless you know you need this.
2688
2689source "drivers/pci/Kconfig"
2690
2691config ISA_BUS
2692	bool "ISA bus support on modern systems" if EXPERT
2693	help
2694	  Expose ISA bus device drivers and options available for selection and
2695	  configuration. Enable this option if your target machine has an ISA
2696	  bus. ISA is an older system, displaced by PCI and newer bus
2697	  architectures -- if your target machine is modern, it probably does
2698	  not have an ISA bus.
2699
2700	  If unsure, say N.
2701
2702# x86_64 have no ISA slots, but can have ISA-style DMA.
2703config ISA_DMA_API
2704	bool "ISA-style DMA support" if (X86_64 && EXPERT)
2705	default y
2706	help
2707	  Enables ISA-style DMA support for devices requiring such controllers.
2708	  If unsure, say Y.
2709
2710if X86_32
2711
2712config ISA
2713	bool "ISA support"
2714	---help---
2715	  Find out whether you have ISA slots on your motherboard.  ISA is the
2716	  name of a bus system, i.e. the way the CPU talks to the other stuff
2717	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2718	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2719	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2720
2721config EISA
2722	bool "EISA support"
2723	depends on ISA
2724	---help---
2725	  The Extended Industry Standard Architecture (EISA) bus was
2726	  developed as an open alternative to the IBM MicroChannel bus.
2727
2728	  The EISA bus provided some of the features of the IBM MicroChannel
2729	  bus while maintaining backward compatibility with cards made for
2730	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2731	  1995 when it was made obsolete by the PCI bus.
2732
2733	  Say Y here if you are building a kernel for an EISA-based machine.
2734
2735	  Otherwise, say N.
2736
2737source "drivers/eisa/Kconfig"
2738
2739config SCx200
2740	tristate "NatSemi SCx200 support"
2741	---help---
2742	  This provides basic support for National Semiconductor's
2743	  (now AMD's) Geode processors.  The driver probes for the
2744	  PCI-IDs of several on-chip devices, so its a good dependency
2745	  for other scx200_* drivers.
2746
2747	  If compiled as a module, the driver is named scx200.
2748
2749config SCx200HR_TIMER
2750	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2751	depends on SCx200
2752	default y
2753	---help---
2754	  This driver provides a clocksource built upon the on-chip
2755	  27MHz high-resolution timer.  Its also a workaround for
2756	  NSC Geode SC-1100's buggy TSC, which loses time when the
2757	  processor goes idle (as is done by the scheduler).  The
2758	  other workaround is idle=poll boot option.
2759
2760config OLPC
2761	bool "One Laptop Per Child support"
2762	depends on !X86_PAE
2763	select GPIOLIB
2764	select OF
2765	select OF_PROMTREE
2766	select IRQ_DOMAIN
2767	---help---
2768	  Add support for detecting the unique features of the OLPC
2769	  XO hardware.
2770
2771config OLPC_XO1_PM
2772	bool "OLPC XO-1 Power Management"
2773	depends on OLPC && MFD_CS5535=y && PM_SLEEP
2774	---help---
2775	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2776
2777config OLPC_XO1_RTC
2778	bool "OLPC XO-1 Real Time Clock"
2779	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2780	---help---
2781	  Add support for the XO-1 real time clock, which can be used as a
2782	  programmable wakeup source.
2783
2784config OLPC_XO1_SCI
2785	bool "OLPC XO-1 SCI extras"
2786	depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
2787	depends on INPUT=y
2788	select POWER_SUPPLY
2789	---help---
2790	  Add support for SCI-based features of the OLPC XO-1 laptop:
2791	   - EC-driven system wakeups
2792	   - Power button
2793	   - Ebook switch
2794	   - Lid switch
2795	   - AC adapter status updates
2796	   - Battery status updates
2797
2798config OLPC_XO15_SCI
2799	bool "OLPC XO-1.5 SCI extras"
2800	depends on OLPC && ACPI
2801	select POWER_SUPPLY
2802	---help---
2803	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2804	   - EC-driven system wakeups
2805	   - AC adapter status updates
2806	   - Battery status updates
2807
2808config ALIX
2809	bool "PCEngines ALIX System Support (LED setup)"
2810	select GPIOLIB
2811	---help---
2812	  This option enables system support for the PCEngines ALIX.
2813	  At present this just sets up LEDs for GPIO control on
2814	  ALIX2/3/6 boards.  However, other system specific setup should
2815	  get added here.
2816
2817	  Note: You must still enable the drivers for GPIO and LED support
2818	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2819
2820	  Note: You have to set alix.force=1 for boards with Award BIOS.
2821
2822config NET5501
2823	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2824	select GPIOLIB
2825	---help---
2826	  This option enables system support for the Soekris Engineering net5501.
2827
2828config GEOS
2829	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2830	select GPIOLIB
2831	depends on DMI
2832	---help---
2833	  This option enables system support for the Traverse Technologies GEOS.
2834
2835config TS5500
2836	bool "Technologic Systems TS-5500 platform support"
2837	depends on MELAN
2838	select CHECK_SIGNATURE
2839	select NEW_LEDS
2840	select LEDS_CLASS
2841	---help---
2842	  This option enables system support for the Technologic Systems TS-5500.
2843
2844endif # X86_32
2845
2846config AMD_NB
2847	def_bool y
2848	depends on CPU_SUP_AMD && PCI
2849
2850source "drivers/pcmcia/Kconfig"
2851
2852config RAPIDIO
2853	tristate "RapidIO support"
2854	depends on PCI
2855	default n
2856	help
2857	  If enabled this option will include drivers and the core
2858	  infrastructure code to support RapidIO interconnect devices.
2859
2860source "drivers/rapidio/Kconfig"
2861
2862config X86_SYSFB
2863	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2864	help
2865	  Firmwares often provide initial graphics framebuffers so the BIOS,
2866	  bootloader or kernel can show basic video-output during boot for
2867	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2868	  Extensions and EFI-framebuffers for this, which are mostly limited
2869	  to x86.
2870	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2871	  framebuffers so the new generic system-framebuffer drivers can be
2872	  used on x86. If the framebuffer is not compatible with the generic
2873	  modes, it is advertised as fallback platform framebuffer so legacy
2874	  drivers like efifb, vesafb and uvesafb can pick it up.
2875	  If this option is not selected, all system framebuffers are always
2876	  marked as fallback platform framebuffers as usual.
2877
2878	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2879	  not be able to pick up generic system framebuffers if this option
2880	  is selected. You are highly encouraged to enable simplefb as
2881	  replacement if you select this option. simplefb can correctly deal
2882	  with generic system framebuffers. But you should still keep vesafb
2883	  and others enabled as fallback if a system framebuffer is
2884	  incompatible with simplefb.
2885
2886	  If unsure, say Y.
2887
2888endmenu
2889
2890
2891menu "Binary Emulations"
2892
2893config IA32_EMULATION
2894	bool "IA32 Emulation"
2895	depends on X86_64
2896	select ARCH_WANT_OLD_COMPAT_IPC
2897	select BINFMT_ELF
2898	select COMPAT_BINFMT_ELF
2899	select COMPAT_OLD_SIGACTION
2900	---help---
2901	  Include code to run legacy 32-bit programs under a
2902	  64-bit kernel. You should likely turn this on, unless you're
2903	  100% sure that you don't have any 32-bit programs left.
2904
2905config IA32_AOUT
2906	tristate "IA32 a.out support"
2907	depends on IA32_EMULATION
2908	depends on BROKEN
2909	---help---
2910	  Support old a.out binaries in the 32bit emulation.
2911
2912config X86_X32
2913	bool "x32 ABI for 64-bit mode"
2914	depends on X86_64
2915	---help---
2916	  Include code to run binaries for the x32 native 32-bit ABI
2917	  for 64-bit processors.  An x32 process gets access to the
2918	  full 64-bit register file and wide data path while leaving
2919	  pointers at 32 bits for smaller memory footprint.
2920
2921	  You will need a recent binutils (2.22 or later) with
2922	  elf32_x86_64 support enabled to compile a kernel with this
2923	  option set.
2924
2925config COMPAT_32
2926	def_bool y
2927	depends on IA32_EMULATION || X86_32
2928	select HAVE_UID16
2929	select OLD_SIGSUSPEND3
2930
2931config COMPAT
2932	def_bool y
2933	depends on IA32_EMULATION || X86_X32
2934
2935if COMPAT
2936config COMPAT_FOR_U64_ALIGNMENT
2937	def_bool y
2938
2939config SYSVIPC_COMPAT
2940	def_bool y
2941	depends on SYSVIPC
2942endif
2943
2944endmenu
2945
2946
2947config HAVE_ATOMIC_IOMAP
2948	def_bool y
2949	depends on X86_32
2950
2951config X86_DEV_DMA_OPS
2952	bool
2953	depends on X86_64 || STA2X11
2954
2955config X86_DMA_REMAP
2956	bool
2957	depends on STA2X11
2958
2959config HAVE_GENERIC_GUP
2960	def_bool y
2961
2962source "drivers/firmware/Kconfig"
2963
2964source "arch/x86/kvm/Kconfig"
2965