Version:  2.0.40 2.2.26 2.4.37 3.6 3.7 3.8 3.9 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2

Linux/arch/x86/Kconfig

  1 # Select 32 or 64 bit
  2 config 64BIT
  3         bool "64-bit kernel" if ARCH = "x86"
  4         default ARCH != "i386"
  5         ---help---
  6           Say yes to build a 64-bit kernel - formerly known as x86_64
  7           Say no to build a 32-bit kernel - formerly known as i386
  8 
  9 config X86_32
 10         def_bool y
 11         depends on !64BIT
 12 
 13 config X86_64
 14         def_bool y
 15         depends on 64BIT
 16 
 17 ### Arch settings
 18 config X86
 19         def_bool y
 20         select ACPI_LEGACY_TABLES_LOOKUP        if ACPI
 21         select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
 22         select ANON_INODES
 23         select ARCH_CLOCKSOURCE_DATA
 24         select ARCH_DISCARD_MEMBLOCK
 25         select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
 26         select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
 27         select ARCH_HAS_ELF_RANDOMIZE
 28         select ARCH_HAS_FAST_MULTIPLIER
 29         select ARCH_HAS_GCOV_PROFILE_ALL
 30         select ARCH_HAS_PMEM_API
 31         select ARCH_HAS_SG_CHAIN
 32         select ARCH_HAVE_NMI_SAFE_CMPXCHG
 33         select ARCH_MIGHT_HAVE_ACPI_PDC         if ACPI
 34         select ARCH_MIGHT_HAVE_PC_PARPORT
 35         select ARCH_MIGHT_HAVE_PC_SERIO
 36         select ARCH_SUPPORTS_ATOMIC_RMW
 37         select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
 38         select ARCH_SUPPORTS_INT128             if X86_64
 39         select ARCH_SUPPORTS_NUMA_BALANCING     if X86_64
 40         select ARCH_USE_BUILTIN_BSWAP
 41         select ARCH_USE_CMPXCHG_LOCKREF         if X86_64
 42         select ARCH_USE_QUEUED_RWLOCKS
 43         select ARCH_USE_QUEUED_SPINLOCKS
 44         select ARCH_WANTS_DYNAMIC_TASK_STRUCT
 45         select ARCH_WANT_FRAME_POINTERS
 46         select ARCH_WANT_IPC_PARSE_VERSION      if X86_32
 47         select ARCH_WANT_OPTIONAL_GPIOLIB
 48         select BUILDTIME_EXTABLE_SORT
 49         select CLKEVT_I8253
 50         select CLKSRC_I8253                     if X86_32
 51         select CLOCKSOURCE_VALIDATE_LAST_CYCLE
 52         select CLOCKSOURCE_WATCHDOG
 53         select CLONE_BACKWARDS                  if X86_32
 54         select COMPAT_OLD_SIGACTION             if IA32_EMULATION
 55         select DCACHE_WORD_ACCESS
 56         select EDAC_ATOMIC_SCRUB
 57         select EDAC_SUPPORT
 58         select GENERIC_CLOCKEVENTS
 59         select GENERIC_CLOCKEVENTS_BROADCAST    if X86_64 || (X86_32 && X86_LOCAL_APIC)
 60         select GENERIC_CLOCKEVENTS_MIN_ADJUST
 61         select GENERIC_CMOS_UPDATE
 62         select GENERIC_CPU_AUTOPROBE
 63         select GENERIC_EARLY_IOREMAP
 64         select GENERIC_FIND_FIRST_BIT
 65         select GENERIC_IOMAP
 66         select GENERIC_IRQ_PROBE
 67         select GENERIC_IRQ_SHOW
 68         select GENERIC_PENDING_IRQ              if SMP
 69         select GENERIC_SMP_IDLE_THREAD
 70         select GENERIC_STRNCPY_FROM_USER
 71         select GENERIC_STRNLEN_USER
 72         select GENERIC_TIME_VSYSCALL
 73         select HAVE_ACPI_APEI                   if ACPI
 74         select HAVE_ACPI_APEI_NMI               if ACPI
 75         select HAVE_ALIGNED_STRUCT_PAGE         if SLUB
 76         select HAVE_AOUT                        if X86_32
 77         select HAVE_ARCH_AUDITSYSCALL
 78         select HAVE_ARCH_HUGE_VMAP              if X86_64 || X86_PAE
 79         select HAVE_ARCH_JUMP_LABEL
 80         select HAVE_ARCH_KASAN                  if X86_64 && SPARSEMEM_VMEMMAP
 81         select HAVE_ARCH_KGDB
 82         select HAVE_ARCH_KMEMCHECK
 83         select HAVE_ARCH_SECCOMP_FILTER
 84         select HAVE_ARCH_SOFT_DIRTY             if X86_64
 85         select HAVE_ARCH_TRACEHOOK
 86         select HAVE_ARCH_TRANSPARENT_HUGEPAGE
 87         select HAVE_BPF_JIT                     if X86_64
 88         select HAVE_CC_STACKPROTECTOR
 89         select HAVE_CMPXCHG_DOUBLE
 90         select HAVE_CMPXCHG_LOCAL
 91         select HAVE_CONTEXT_TRACKING            if X86_64
 92         select HAVE_COPY_THREAD_TLS
 93         select HAVE_C_RECORDMCOUNT
 94         select HAVE_DEBUG_KMEMLEAK
 95         select HAVE_DEBUG_STACKOVERFLOW
 96         select HAVE_DMA_API_DEBUG
 97         select HAVE_DMA_ATTRS
 98         select HAVE_DMA_CONTIGUOUS
 99         select HAVE_DYNAMIC_FTRACE
100         select HAVE_DYNAMIC_FTRACE_WITH_REGS
101         select HAVE_EFFICIENT_UNALIGNED_ACCESS
102         select HAVE_FENTRY                      if X86_64
103         select HAVE_FTRACE_MCOUNT_RECORD
104         select HAVE_FUNCTION_GRAPH_FP_TEST
105         select HAVE_FUNCTION_GRAPH_TRACER
106         select HAVE_FUNCTION_TRACER
107         select HAVE_GENERIC_DMA_COHERENT        if X86_32
108         select HAVE_HW_BREAKPOINT
109         select HAVE_IDE
110         select HAVE_IOREMAP_PROT
111         select HAVE_IRQ_EXIT_ON_IRQ_STACK       if X86_64
112         select HAVE_IRQ_TIME_ACCOUNTING
113         select HAVE_KERNEL_BZIP2
114         select HAVE_KERNEL_GZIP
115         select HAVE_KERNEL_LZ4
116         select HAVE_KERNEL_LZMA
117         select HAVE_KERNEL_LZO
118         select HAVE_KERNEL_XZ
119         select HAVE_KPROBES
120         select HAVE_KPROBES_ON_FTRACE
121         select HAVE_KRETPROBES
122         select HAVE_KVM
123         select HAVE_LIVEPATCH                   if X86_64
124         select HAVE_MEMBLOCK
125         select HAVE_MEMBLOCK_NODE_MAP
126         select HAVE_MIXED_BREAKPOINTS_REGS
127         select HAVE_OPROFILE
128         select HAVE_OPTPROBES
129         select HAVE_PCSPKR_PLATFORM
130         select HAVE_PERF_EVENTS
131         select HAVE_PERF_EVENTS_NMI
132         select HAVE_PERF_REGS
133         select HAVE_PERF_USER_STACK_DUMP
134         select HAVE_REGS_AND_STACK_ACCESS_API
135         select HAVE_SYSCALL_TRACEPOINTS
136         select HAVE_UID16                       if X86_32
137         select HAVE_UNSTABLE_SCHED_CLOCK
138         select HAVE_USER_RETURN_NOTIFIER
139         select IRQ_FORCED_THREADING
140         select MODULES_USE_ELF_RELA             if X86_64
141         select MODULES_USE_ELF_REL              if X86_32
142         select OLD_SIGACTION                    if X86_32
143         select OLD_SIGSUSPEND3                  if X86_32 || IA32_EMULATION
144         select PERF_EVENTS
145         select RTC_LIB
146         select SPARSE_IRQ
147         select SRCU
148         select SYSCTL_EXCEPTION_TRACE
149         select USER_STACKTRACE_SUPPORT
150         select VIRT_TO_BUS
151         select X86_DEV_DMA_OPS                  if X86_64
152         select X86_FEATURE_NAMES                if PROC_FS
153 
154 config INSTRUCTION_DECODER
155         def_bool y
156         depends on KPROBES || PERF_EVENTS || UPROBES
157 
158 config PERF_EVENTS_INTEL_UNCORE
159         def_bool y
160         depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
161 
162 config OUTPUT_FORMAT
163         string
164         default "elf32-i386" if X86_32
165         default "elf64-x86-64" if X86_64
166 
167 config ARCH_DEFCONFIG
168         string
169         default "arch/x86/configs/i386_defconfig" if X86_32
170         default "arch/x86/configs/x86_64_defconfig" if X86_64
171 
172 config LOCKDEP_SUPPORT
173         def_bool y
174 
175 config STACKTRACE_SUPPORT
176         def_bool y
177 
178 config HAVE_LATENCYTOP_SUPPORT
179         def_bool y
180 
181 config MMU
182         def_bool y
183 
184 config SBUS
185         bool
186 
187 config NEED_DMA_MAP_STATE
188         def_bool y
189         depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
190 
191 config NEED_SG_DMA_LENGTH
192         def_bool y
193 
194 config GENERIC_ISA_DMA
195         def_bool y
196         depends on ISA_DMA_API
197 
198 config GENERIC_BUG
199         def_bool y
200         depends on BUG
201         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
202 
203 config GENERIC_BUG_RELATIVE_POINTERS
204         bool
205 
206 config GENERIC_HWEIGHT
207         def_bool y
208 
209 config ARCH_MAY_HAVE_PC_FDC
210         def_bool y
211         depends on ISA_DMA_API
212 
213 config RWSEM_XCHGADD_ALGORITHM
214         def_bool y
215 
216 config GENERIC_CALIBRATE_DELAY
217         def_bool y
218 
219 config ARCH_HAS_CPU_RELAX
220         def_bool y
221 
222 config ARCH_HAS_CACHE_LINE_SIZE
223         def_bool y
224 
225 config HAVE_SETUP_PER_CPU_AREA
226         def_bool y
227 
228 config NEED_PER_CPU_EMBED_FIRST_CHUNK
229         def_bool y
230 
231 config NEED_PER_CPU_PAGE_FIRST_CHUNK
232         def_bool y
233 
234 config ARCH_HIBERNATION_POSSIBLE
235         def_bool y
236 
237 config ARCH_SUSPEND_POSSIBLE
238         def_bool y
239 
240 config ARCH_WANT_HUGE_PMD_SHARE
241         def_bool y
242 
243 config ARCH_WANT_GENERAL_HUGETLB
244         def_bool y
245 
246 config ZONE_DMA32
247         def_bool y if X86_64
248 
249 config AUDIT_ARCH
250         def_bool y if X86_64
251 
252 config ARCH_SUPPORTS_OPTIMIZED_INLINING
253         def_bool y
254 
255 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
256         def_bool y
257 
258 config KASAN_SHADOW_OFFSET
259         hex
260         depends on KASAN
261         default 0xdffffc0000000000
262 
263 config HAVE_INTEL_TXT
264         def_bool y
265         depends on INTEL_IOMMU && ACPI
266 
267 config X86_32_SMP
268         def_bool y
269         depends on X86_32 && SMP
270 
271 config X86_64_SMP
272         def_bool y
273         depends on X86_64 && SMP
274 
275 config X86_32_LAZY_GS
276         def_bool y
277         depends on X86_32 && !CC_STACKPROTECTOR
278 
279 config ARCH_HWEIGHT_CFLAGS
280         string
281         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
282         default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
283 
284 config ARCH_SUPPORTS_UPROBES
285         def_bool y
286 
287 config FIX_EARLYCON_MEM
288         def_bool y
289 
290 config PGTABLE_LEVELS
291         int
292         default 4 if X86_64
293         default 3 if X86_PAE
294         default 2
295 
296 source "init/Kconfig"
297 source "kernel/Kconfig.freezer"
298 
299 menu "Processor type and features"
300 
301 config ZONE_DMA
302         bool "DMA memory allocation support" if EXPERT
303         default y
304         help
305           DMA memory allocation support allows devices with less than 32-bit
306           addressing to allocate within the first 16MB of address space.
307           Disable if no such devices will be used.
308 
309           If unsure, say Y.
310 
311 config SMP
312         bool "Symmetric multi-processing support"
313         ---help---
314           This enables support for systems with more than one CPU. If you have
315           a system with only one CPU, say N. If you have a system with more
316           than one CPU, say Y.
317 
318           If you say N here, the kernel will run on uni- and multiprocessor
319           machines, but will use only one CPU of a multiprocessor machine. If
320           you say Y here, the kernel will run on many, but not all,
321           uniprocessor machines. On a uniprocessor machine, the kernel
322           will run faster if you say N here.
323 
324           Note that if you say Y here and choose architecture "586" or
325           "Pentium" under "Processor family", the kernel will not work on 486
326           architectures. Similarly, multiprocessor kernels for the "PPro"
327           architecture may not work on all Pentium based boards.
328 
329           People using multiprocessor machines who say Y here should also say
330           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
331           Management" code will be disabled if you say Y here.
332 
333           See also <file:Documentation/x86/i386/IO-APIC.txt>,
334           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
335           <http://www.tldp.org/docs.html#howto>.
336 
337           If you don't know what to do here, say N.
338 
339 config X86_FEATURE_NAMES
340         bool "Processor feature human-readable names" if EMBEDDED
341         default y
342         ---help---
343           This option compiles in a table of x86 feature bits and corresponding
344           names.  This is required to support /proc/cpuinfo and a few kernel
345           messages.  You can disable this to save space, at the expense of
346           making those few kernel messages show numeric feature bits instead.
347 
348           If in doubt, say Y.
349 
350 config X86_X2APIC
351         bool "Support x2apic"
352         depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
353         ---help---
354           This enables x2apic support on CPUs that have this feature.
355 
356           This allows 32-bit apic IDs (so it can support very large systems),
357           and accesses the local apic via MSRs not via mmio.
358 
359           If you don't know what to do here, say N.
360 
361 config X86_MPPARSE
362         bool "Enable MPS table" if ACPI || SFI
363         default y
364         depends on X86_LOCAL_APIC
365         ---help---
366           For old smp systems that do not have proper acpi support. Newer systems
367           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
368 
369 config X86_BIGSMP
370         bool "Support for big SMP systems with more than 8 CPUs"
371         depends on X86_32 && SMP
372         ---help---
373           This option is needed for the systems that have more than 8 CPUs
374 
375 config GOLDFISH
376        def_bool y
377        depends on X86_GOLDFISH
378 
379 if X86_32
380 config X86_EXTENDED_PLATFORM
381         bool "Support for extended (non-PC) x86 platforms"
382         default y
383         ---help---
384           If you disable this option then the kernel will only support
385           standard PC platforms. (which covers the vast majority of
386           systems out there.)
387 
388           If you enable this option then you'll be able to select support
389           for the following (non-PC) 32 bit x86 platforms:
390                 Goldfish (Android emulator)
391                 AMD Elan
392                 RDC R-321x SoC
393                 SGI 320/540 (Visual Workstation)
394                 STA2X11-based (e.g. Northville)
395                 Moorestown MID devices
396 
397           If you have one of these systems, or if you want to build a
398           generic distribution kernel, say Y here - otherwise say N.
399 endif
400 
401 if X86_64
402 config X86_EXTENDED_PLATFORM
403         bool "Support for extended (non-PC) x86 platforms"
404         default y
405         ---help---
406           If you disable this option then the kernel will only support
407           standard PC platforms. (which covers the vast majority of
408           systems out there.)
409 
410           If you enable this option then you'll be able to select support
411           for the following (non-PC) 64 bit x86 platforms:
412                 Numascale NumaChip
413                 ScaleMP vSMP
414                 SGI Ultraviolet
415 
416           If you have one of these systems, or if you want to build a
417           generic distribution kernel, say Y here - otherwise say N.
418 endif
419 # This is an alphabetically sorted list of 64 bit extended platforms
420 # Please maintain the alphabetic order if and when there are additions
421 config X86_NUMACHIP
422         bool "Numascale NumaChip"
423         depends on X86_64
424         depends on X86_EXTENDED_PLATFORM
425         depends on NUMA
426         depends on SMP
427         depends on X86_X2APIC
428         depends on PCI_MMCONFIG
429         ---help---
430           Adds support for Numascale NumaChip large-SMP systems. Needed to
431           enable more than ~168 cores.
432           If you don't have one of these, you should say N here.
433 
434 config X86_VSMP
435         bool "ScaleMP vSMP"
436         select HYPERVISOR_GUEST
437         select PARAVIRT
438         depends on X86_64 && PCI
439         depends on X86_EXTENDED_PLATFORM
440         depends on SMP
441         ---help---
442           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
443           supposed to run on these EM64T-based machines.  Only choose this option
444           if you have one of these machines.
445 
446 config X86_UV
447         bool "SGI Ultraviolet"
448         depends on X86_64
449         depends on X86_EXTENDED_PLATFORM
450         depends on NUMA
451         depends on X86_X2APIC
452         depends on PCI
453         ---help---
454           This option is needed in order to support SGI Ultraviolet systems.
455           If you don't have one of these, you should say N here.
456 
457 # Following is an alphabetically sorted list of 32 bit extended platforms
458 # Please maintain the alphabetic order if and when there are additions
459 
460 config X86_GOLDFISH
461        bool "Goldfish (Virtual Platform)"
462        depends on X86_EXTENDED_PLATFORM
463        ---help---
464          Enable support for the Goldfish virtual platform used primarily
465          for Android development. Unless you are building for the Android
466          Goldfish emulator say N here.
467 
468 config X86_INTEL_CE
469         bool "CE4100 TV platform"
470         depends on PCI
471         depends on PCI_GODIRECT
472         depends on X86_IO_APIC
473         depends on X86_32
474         depends on X86_EXTENDED_PLATFORM
475         select X86_REBOOTFIXUPS
476         select OF
477         select OF_EARLY_FLATTREE
478         ---help---
479           Select for the Intel CE media processor (CE4100) SOC.
480           This option compiles in support for the CE4100 SOC for settop
481           boxes and media devices.
482 
483 config X86_INTEL_MID
484         bool "Intel MID platform support"
485         depends on X86_32
486         depends on X86_EXTENDED_PLATFORM
487         depends on X86_PLATFORM_DEVICES
488         depends on PCI
489         depends on PCI_GOANY
490         depends on X86_IO_APIC
491         select SFI
492         select I2C
493         select DW_APB_TIMER
494         select APB_TIMER
495         select INTEL_SCU_IPC
496         select MFD_INTEL_MSIC
497         ---help---
498           Select to build a kernel capable of supporting Intel MID (Mobile
499           Internet Device) platform systems which do not have the PCI legacy
500           interfaces. If you are building for a PC class system say N here.
501 
502           Intel MID platforms are based on an Intel processor and chipset which
503           consume less power than most of the x86 derivatives.
504 
505 config X86_INTEL_QUARK
506         bool "Intel Quark platform support"
507         depends on X86_32
508         depends on X86_EXTENDED_PLATFORM
509         depends on X86_PLATFORM_DEVICES
510         depends on X86_TSC
511         depends on PCI
512         depends on PCI_GOANY
513         depends on X86_IO_APIC
514         select IOSF_MBI
515         select INTEL_IMR
516         select COMMON_CLK
517         ---help---
518           Select to include support for Quark X1000 SoC.
519           Say Y here if you have a Quark based system such as the Arduino
520           compatible Intel Galileo.
521 
522 config X86_INTEL_LPSS
523         bool "Intel Low Power Subsystem Support"
524         depends on ACPI
525         select COMMON_CLK
526         select PINCTRL
527         ---help---
528           Select to build support for Intel Low Power Subsystem such as
529           found on Intel Lynxpoint PCH. Selecting this option enables
530           things like clock tree (common clock framework) and pincontrol
531           which are needed by the LPSS peripheral drivers.
532 
533 config X86_AMD_PLATFORM_DEVICE
534         bool "AMD ACPI2Platform devices support"
535         depends on ACPI
536         select COMMON_CLK
537         select PINCTRL
538         ---help---
539           Select to interpret AMD specific ACPI device to platform device
540           such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
541           I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
542           implemented under PINCTRL subsystem.
543 
544 config IOSF_MBI
545         tristate "Intel SoC IOSF Sideband support for SoC platforms"
546         depends on PCI
547         ---help---
548           This option enables sideband register access support for Intel SoC
549           platforms. On these platforms the IOSF sideband is used in lieu of
550           MSR's for some register accesses, mostly but not limited to thermal
551           and power. Drivers may query the availability of this device to
552           determine if they need the sideband in order to work on these
553           platforms. The sideband is available on the following SoC products.
554           This list is not meant to be exclusive.
555            - BayTrail
556            - Braswell
557            - Quark
558 
559           You should say Y if you are running a kernel on one of these SoC's.
560 
561 config IOSF_MBI_DEBUG
562         bool "Enable IOSF sideband access through debugfs"
563         depends on IOSF_MBI && DEBUG_FS
564         ---help---
565           Select this option to expose the IOSF sideband access registers (MCR,
566           MDR, MCRX) through debugfs to write and read register information from
567           different units on the SoC. This is most useful for obtaining device
568           state information for debug and analysis. As this is a general access
569           mechanism, users of this option would have specific knowledge of the
570           device they want to access.
571 
572           If you don't require the option or are in doubt, say N.
573 
574 config X86_RDC321X
575         bool "RDC R-321x SoC"
576         depends on X86_32
577         depends on X86_EXTENDED_PLATFORM
578         select M486
579         select X86_REBOOTFIXUPS
580         ---help---
581           This option is needed for RDC R-321x system-on-chip, also known
582           as R-8610-(G).
583           If you don't have one of these chips, you should say N here.
584 
585 config X86_32_NON_STANDARD
586         bool "Support non-standard 32-bit SMP architectures"
587         depends on X86_32 && SMP
588         depends on X86_EXTENDED_PLATFORM
589         ---help---
590           This option compiles in the bigsmp and STA2X11 default
591           subarchitectures.  It is intended for a generic binary
592           kernel. If you select them all, kernel will probe it one by
593           one and will fallback to default.
594 
595 # Alphabetically sorted list of Non standard 32 bit platforms
596 
597 config X86_SUPPORTS_MEMORY_FAILURE
598         def_bool y
599         # MCE code calls memory_failure():
600         depends on X86_MCE
601         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
602         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
603         depends on X86_64 || !SPARSEMEM
604         select ARCH_SUPPORTS_MEMORY_FAILURE
605 
606 config STA2X11
607         bool "STA2X11 Companion Chip Support"
608         depends on X86_32_NON_STANDARD && PCI
609         select X86_DEV_DMA_OPS
610         select X86_DMA_REMAP
611         select SWIOTLB
612         select MFD_STA2X11
613         select ARCH_REQUIRE_GPIOLIB
614         default n
615         ---help---
616           This adds support for boards based on the STA2X11 IO-Hub,
617           a.k.a. "ConneXt". The chip is used in place of the standard
618           PC chipset, so all "standard" peripherals are missing. If this
619           option is selected the kernel will still be able to boot on
620           standard PC machines.
621 
622 config X86_32_IRIS
623         tristate "Eurobraille/Iris poweroff module"
624         depends on X86_32
625         ---help---
626           The Iris machines from EuroBraille do not have APM or ACPI support
627           to shut themselves down properly.  A special I/O sequence is
628           needed to do so, which is what this module does at
629           kernel shutdown.
630 
631           This is only for Iris machines from EuroBraille.
632 
633           If unused, say N.
634 
635 config SCHED_OMIT_FRAME_POINTER
636         def_bool y
637         prompt "Single-depth WCHAN output"
638         depends on X86
639         ---help---
640           Calculate simpler /proc/<PID>/wchan values. If this option
641           is disabled then wchan values will recurse back to the
642           caller function. This provides more accurate wchan values,
643           at the expense of slightly more scheduling overhead.
644 
645           If in doubt, say "Y".
646 
647 menuconfig HYPERVISOR_GUEST
648         bool "Linux guest support"
649         ---help---
650           Say Y here to enable options for running Linux under various hyper-
651           visors. This option enables basic hypervisor detection and platform
652           setup.
653 
654           If you say N, all options in this submenu will be skipped and
655           disabled, and Linux guest support won't be built in.
656 
657 if HYPERVISOR_GUEST
658 
659 config PARAVIRT
660         bool "Enable paravirtualization code"
661         ---help---
662           This changes the kernel so it can modify itself when it is run
663           under a hypervisor, potentially improving performance significantly
664           over full virtualization.  However, when run without a hypervisor
665           the kernel is theoretically slower and slightly larger.
666 
667 config PARAVIRT_DEBUG
668         bool "paravirt-ops debugging"
669         depends on PARAVIRT && DEBUG_KERNEL
670         ---help---
671           Enable to debug paravirt_ops internals.  Specifically, BUG if
672           a paravirt_op is missing when it is called.
673 
674 config PARAVIRT_SPINLOCKS
675         bool "Paravirtualization layer for spinlocks"
676         depends on PARAVIRT && SMP
677         select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
678         ---help---
679           Paravirtualized spinlocks allow a pvops backend to replace the
680           spinlock implementation with something virtualization-friendly
681           (for example, block the virtual CPU rather than spinning).
682 
683           It has a minimal impact on native kernels and gives a nice performance
684           benefit on paravirtualized KVM / Xen kernels.
685 
686           If you are unsure how to answer this question, answer Y.
687 
688 source "arch/x86/xen/Kconfig"
689 
690 config KVM_GUEST
691         bool "KVM Guest support (including kvmclock)"
692         depends on PARAVIRT
693         select PARAVIRT_CLOCK
694         default y
695         ---help---
696           This option enables various optimizations for running under the KVM
697           hypervisor. It includes a paravirtualized clock, so that instead
698           of relying on a PIT (or probably other) emulation by the
699           underlying device model, the host provides the guest with
700           timing infrastructure such as time of day, and system time
701 
702 config KVM_DEBUG_FS
703         bool "Enable debug information for KVM Guests in debugfs"
704         depends on KVM_GUEST && DEBUG_FS
705         default n
706         ---help---
707           This option enables collection of various statistics for KVM guest.
708           Statistics are displayed in debugfs filesystem. Enabling this option
709           may incur significant overhead.
710 
711 source "arch/x86/lguest/Kconfig"
712 
713 config PARAVIRT_TIME_ACCOUNTING
714         bool "Paravirtual steal time accounting"
715         depends on PARAVIRT
716         default n
717         ---help---
718           Select this option to enable fine granularity task steal time
719           accounting. Time spent executing other tasks in parallel with
720           the current vCPU is discounted from the vCPU power. To account for
721           that, there can be a small performance impact.
722 
723           If in doubt, say N here.
724 
725 config PARAVIRT_CLOCK
726         bool
727 
728 endif #HYPERVISOR_GUEST
729 
730 config NO_BOOTMEM
731         def_bool y
732 
733 source "arch/x86/Kconfig.cpu"
734 
735 config HPET_TIMER
736         def_bool X86_64
737         prompt "HPET Timer Support" if X86_32
738         ---help---
739           Use the IA-PC HPET (High Precision Event Timer) to manage
740           time in preference to the PIT and RTC, if a HPET is
741           present.
742           HPET is the next generation timer replacing legacy 8254s.
743           The HPET provides a stable time base on SMP
744           systems, unlike the TSC, but it is more expensive to access,
745           as it is off-chip.  You can find the HPET spec at
746           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
747 
748           You can safely choose Y here.  However, HPET will only be
749           activated if the platform and the BIOS support this feature.
750           Otherwise the 8254 will be used for timing services.
751 
752           Choose N to continue using the legacy 8254 timer.
753 
754 config HPET_EMULATE_RTC
755         def_bool y
756         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
757 
758 config APB_TIMER
759        def_bool y if X86_INTEL_MID
760        prompt "Intel MID APB Timer Support" if X86_INTEL_MID
761        select DW_APB_TIMER
762        depends on X86_INTEL_MID && SFI
763        help
764          APB timer is the replacement for 8254, HPET on X86 MID platforms.
765          The APBT provides a stable time base on SMP
766          systems, unlike the TSC, but it is more expensive to access,
767          as it is off-chip. APB timers are always running regardless of CPU
768          C states, they are used as per CPU clockevent device when possible.
769 
770 # Mark as expert because too many people got it wrong.
771 # The code disables itself when not needed.
772 config DMI
773         default y
774         select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
775         bool "Enable DMI scanning" if EXPERT
776         ---help---
777           Enabled scanning of DMI to identify machine quirks. Say Y
778           here unless you have verified that your setup is not
779           affected by entries in the DMI blacklist. Required by PNP
780           BIOS code.
781 
782 config GART_IOMMU
783         bool "Old AMD GART IOMMU support"
784         select SWIOTLB
785         depends on X86_64 && PCI && AMD_NB
786         ---help---
787           Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
788           GART based hardware IOMMUs.
789 
790           The GART supports full DMA access for devices with 32-bit access
791           limitations, on systems with more than 3 GB. This is usually needed
792           for USB, sound, many IDE/SATA chipsets and some other devices.
793 
794           Newer systems typically have a modern AMD IOMMU, supported via
795           the CONFIG_AMD_IOMMU=y config option.
796 
797           In normal configurations this driver is only active when needed:
798           there's more than 3 GB of memory and the system contains a
799           32-bit limited device.
800 
801           If unsure, say Y.
802 
803 config CALGARY_IOMMU
804         bool "IBM Calgary IOMMU support"
805         select SWIOTLB
806         depends on X86_64 && PCI
807         ---help---
808           Support for hardware IOMMUs in IBM's xSeries x366 and x460
809           systems. Needed to run systems with more than 3GB of memory
810           properly with 32-bit PCI devices that do not support DAC
811           (Double Address Cycle). Calgary also supports bus level
812           isolation, where all DMAs pass through the IOMMU.  This
813           prevents them from going anywhere except their intended
814           destination. This catches hard-to-find kernel bugs and
815           mis-behaving drivers and devices that do not use the DMA-API
816           properly to set up their DMA buffers.  The IOMMU can be
817           turned off at boot time with the iommu=off parameter.
818           Normally the kernel will make the right choice by itself.
819           If unsure, say Y.
820 
821 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
822         def_bool y
823         prompt "Should Calgary be enabled by default?"
824         depends on CALGARY_IOMMU
825         ---help---
826           Should Calgary be enabled by default? if you choose 'y', Calgary
827           will be used (if it exists). If you choose 'n', Calgary will not be
828           used even if it exists. If you choose 'n' and would like to use
829           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
830           If unsure, say Y.
831 
832 # need this always selected by IOMMU for the VIA workaround
833 config SWIOTLB
834         def_bool y if X86_64
835         ---help---
836           Support for software bounce buffers used on x86-64 systems
837           which don't have a hardware IOMMU. Using this PCI devices
838           which can only access 32-bits of memory can be used on systems
839           with more than 3 GB of memory.
840           If unsure, say Y.
841 
842 config IOMMU_HELPER
843         def_bool y
844         depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
845 
846 config MAXSMP
847         bool "Enable Maximum number of SMP Processors and NUMA Nodes"
848         depends on X86_64 && SMP && DEBUG_KERNEL
849         select CPUMASK_OFFSTACK
850         ---help---
851           Enable maximum number of CPUS and NUMA Nodes for this architecture.
852           If unsure, say N.
853 
854 config NR_CPUS
855         int "Maximum number of CPUs" if SMP && !MAXSMP
856         range 2 8 if SMP && X86_32 && !X86_BIGSMP
857         range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
858         range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
859         default "1" if !SMP
860         default "8192" if MAXSMP
861         default "32" if SMP && X86_BIGSMP
862         default "8" if SMP && X86_32
863         default "64" if SMP
864         ---help---
865           This allows you to specify the maximum number of CPUs which this
866           kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
867           supported value is 8192, otherwise the maximum value is 512.  The
868           minimum value which makes sense is 2.
869 
870           This is purely to save memory - each supported CPU adds
871           approximately eight kilobytes to the kernel image.
872 
873 config SCHED_SMT
874         bool "SMT (Hyperthreading) scheduler support"
875         depends on SMP
876         ---help---
877           SMT scheduler support improves the CPU scheduler's decision making
878           when dealing with Intel Pentium 4 chips with HyperThreading at a
879           cost of slightly increased overhead in some places. If unsure say
880           N here.
881 
882 config SCHED_MC
883         def_bool y
884         prompt "Multi-core scheduler support"
885         depends on SMP
886         ---help---
887           Multi-core scheduler support improves the CPU scheduler's decision
888           making when dealing with multi-core CPU chips at a cost of slightly
889           increased overhead in some places. If unsure say N here.
890 
891 source "kernel/Kconfig.preempt"
892 
893 config UP_LATE_INIT
894        def_bool y
895        depends on !SMP && X86_LOCAL_APIC
896 
897 config X86_UP_APIC
898         bool "Local APIC support on uniprocessors" if !PCI_MSI
899         default PCI_MSI
900         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
901         ---help---
902           A local APIC (Advanced Programmable Interrupt Controller) is an
903           integrated interrupt controller in the CPU. If you have a single-CPU
904           system which has a processor with a local APIC, you can say Y here to
905           enable and use it. If you say Y here even though your machine doesn't
906           have a local APIC, then the kernel will still run with no slowdown at
907           all. The local APIC supports CPU-generated self-interrupts (timer,
908           performance counters), and the NMI watchdog which detects hard
909           lockups.
910 
911 config X86_UP_IOAPIC
912         bool "IO-APIC support on uniprocessors"
913         depends on X86_UP_APIC
914         ---help---
915           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
916           SMP-capable replacement for PC-style interrupt controllers. Most
917           SMP systems and many recent uniprocessor systems have one.
918 
919           If you have a single-CPU system with an IO-APIC, you can say Y here
920           to use it. If you say Y here even though your machine doesn't have
921           an IO-APIC, then the kernel will still run with no slowdown at all.
922 
923 config X86_LOCAL_APIC
924         def_bool y
925         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
926         select IRQ_DOMAIN_HIERARCHY
927         select PCI_MSI_IRQ_DOMAIN if PCI_MSI
928 
929 config X86_IO_APIC
930         def_bool y
931         depends on X86_LOCAL_APIC || X86_UP_IOAPIC
932 
933 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
934         bool "Reroute for broken boot IRQs"
935         depends on X86_IO_APIC
936         ---help---
937           This option enables a workaround that fixes a source of
938           spurious interrupts. This is recommended when threaded
939           interrupt handling is used on systems where the generation of
940           superfluous "boot interrupts" cannot be disabled.
941 
942           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
943           entry in the chipset's IO-APIC is masked (as, e.g. the RT
944           kernel does during interrupt handling). On chipsets where this
945           boot IRQ generation cannot be disabled, this workaround keeps
946           the original IRQ line masked so that only the equivalent "boot
947           IRQ" is delivered to the CPUs. The workaround also tells the
948           kernel to set up the IRQ handler on the boot IRQ line. In this
949           way only one interrupt is delivered to the kernel. Otherwise
950           the spurious second interrupt may cause the kernel to bring
951           down (vital) interrupt lines.
952 
953           Only affects "broken" chipsets. Interrupt sharing may be
954           increased on these systems.
955 
956 config X86_MCE
957         bool "Machine Check / overheating reporting"
958         default y
959         ---help---
960           Machine Check support allows the processor to notify the
961           kernel if it detects a problem (e.g. overheating, data corruption).
962           The action the kernel takes depends on the severity of the problem,
963           ranging from warning messages to halting the machine.
964 
965 config X86_MCE_INTEL
966         def_bool y
967         prompt "Intel MCE features"
968         depends on X86_MCE && X86_LOCAL_APIC
969         ---help---
970            Additional support for intel specific MCE features such as
971            the thermal monitor.
972 
973 config X86_MCE_AMD
974         def_bool y
975         prompt "AMD MCE features"
976         depends on X86_MCE && X86_LOCAL_APIC
977         ---help---
978            Additional support for AMD specific MCE features such as
979            the DRAM Error Threshold.
980 
981 config X86_ANCIENT_MCE
982         bool "Support for old Pentium 5 / WinChip machine checks"
983         depends on X86_32 && X86_MCE
984         ---help---
985           Include support for machine check handling on old Pentium 5 or WinChip
986           systems. These typically need to be enabled explicitly on the command
987           line.
988 
989 config X86_MCE_THRESHOLD
990         depends on X86_MCE_AMD || X86_MCE_INTEL
991         def_bool y
992 
993 config X86_MCE_INJECT
994         depends on X86_MCE
995         tristate "Machine check injector support"
996         ---help---
997           Provide support for injecting machine checks for testing purposes.
998           If you don't know what a machine check is and you don't do kernel
999           QA it is safe to say n.
1000 
1001 config X86_THERMAL_VECTOR
1002         def_bool y
1003         depends on X86_MCE_INTEL
1004 
1005 config VM86
1006         bool "Enable VM86 support" if EXPERT
1007         default y
1008         depends on X86_32
1009         ---help---
1010           This option is required by programs like DOSEMU to run
1011           16-bit real mode legacy code on x86 processors. It also may
1012           be needed by software like XFree86 to initialize some video
1013           cards via BIOS. Disabling this option saves about 6K.
1014 
1015 config X86_16BIT
1016         bool "Enable support for 16-bit segments" if EXPERT
1017         default y
1018         ---help---
1019           This option is required by programs like Wine to run 16-bit
1020           protected mode legacy code on x86 processors.  Disabling
1021           this option saves about 300 bytes on i386, or around 6K text
1022           plus 16K runtime memory on x86-64,
1023 
1024 config X86_ESPFIX32
1025         def_bool y
1026         depends on X86_16BIT && X86_32
1027 
1028 config X86_ESPFIX64
1029         def_bool y
1030         depends on X86_16BIT && X86_64
1031 
1032 config X86_VSYSCALL_EMULATION
1033        bool "Enable vsyscall emulation" if EXPERT
1034        default y
1035        depends on X86_64
1036        ---help---
1037          This enables emulation of the legacy vsyscall page.  Disabling
1038          it is roughly equivalent to booting with vsyscall=none, except
1039          that it will also disable the helpful warning if a program
1040          tries to use a vsyscall.  With this option set to N, offending
1041          programs will just segfault, citing addresses of the form
1042          0xffffffffff600?00.
1043 
1044          This option is required by many programs built before 2013, and
1045          care should be used even with newer programs if set to N.
1046 
1047          Disabling this option saves about 7K of kernel size and
1048          possibly 4K of additional runtime pagetable memory.
1049 
1050 config TOSHIBA
1051         tristate "Toshiba Laptop support"
1052         depends on X86_32
1053         ---help---
1054           This adds a driver to safely access the System Management Mode of
1055           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1056           not work on models with a Phoenix BIOS. The System Management Mode
1057           is used to set the BIOS and power saving options on Toshiba portables.
1058 
1059           For information on utilities to make use of this driver see the
1060           Toshiba Linux utilities web site at:
1061           <http://www.buzzard.org.uk/toshiba/>.
1062 
1063           Say Y if you intend to run this kernel on a Toshiba portable.
1064           Say N otherwise.
1065 
1066 config I8K
1067         tristate "Dell i8k legacy laptop support"
1068         select HWMON
1069         select SENSORS_DELL_SMM
1070         ---help---
1071           This option enables legacy /proc/i8k userspace interface in hwmon
1072           dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1073           temperature and allows controlling fan speeds of Dell laptops via
1074           System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1075           it reports also power and hotkey status. For fan speed control is
1076           needed userspace package i8kutils.
1077 
1078           Say Y if you intend to run this kernel on old Dell laptops or want to
1079           use userspace package i8kutils.
1080           Say N otherwise.
1081 
1082 config X86_REBOOTFIXUPS
1083         bool "Enable X86 board specific fixups for reboot"
1084         depends on X86_32
1085         ---help---
1086           This enables chipset and/or board specific fixups to be done
1087           in order to get reboot to work correctly. This is only needed on
1088           some combinations of hardware and BIOS. The symptom, for which
1089           this config is intended, is when reboot ends with a stalled/hung
1090           system.
1091 
1092           Currently, the only fixup is for the Geode machines using
1093           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1094 
1095           Say Y if you want to enable the fixup. Currently, it's safe to
1096           enable this option even if you don't need it.
1097           Say N otherwise.
1098 
1099 config MICROCODE
1100         tristate "CPU microcode loading support"
1101         depends on CPU_SUP_AMD || CPU_SUP_INTEL
1102         select FW_LOADER
1103         ---help---
1104 
1105           If you say Y here, you will be able to update the microcode on
1106           certain Intel and AMD processors. The Intel support is for the
1107           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1108           Xeon etc. The AMD support is for families 0x10 and later. You will
1109           obviously need the actual microcode binary data itself which is not
1110           shipped with the Linux kernel.
1111 
1112           This option selects the general module only, you need to select
1113           at least one vendor specific module as well.
1114 
1115           To compile this driver as a module, choose M here: the module
1116           will be called microcode.
1117 
1118 config MICROCODE_INTEL
1119         bool "Intel microcode loading support"
1120         depends on MICROCODE
1121         default MICROCODE
1122         select FW_LOADER
1123         ---help---
1124           This options enables microcode patch loading support for Intel
1125           processors.
1126 
1127           For the current Intel microcode data package go to
1128           <https://downloadcenter.intel.com> and search for
1129           'Linux Processor Microcode Data File'.
1130 
1131 config MICROCODE_AMD
1132         bool "AMD microcode loading support"
1133         depends on MICROCODE
1134         select FW_LOADER
1135         ---help---
1136           If you select this option, microcode patch loading support for AMD
1137           processors will be enabled.
1138 
1139 config MICROCODE_OLD_INTERFACE
1140         def_bool y
1141         depends on MICROCODE
1142 
1143 config MICROCODE_INTEL_EARLY
1144         bool
1145 
1146 config MICROCODE_AMD_EARLY
1147         bool
1148 
1149 config MICROCODE_EARLY
1150         bool "Early load microcode"
1151         depends on MICROCODE=y && BLK_DEV_INITRD
1152         select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1153         select MICROCODE_AMD_EARLY if MICROCODE_AMD
1154         default y
1155         help
1156           This option provides functionality to read additional microcode data
1157           at the beginning of initrd image. The data tells kernel to load
1158           microcode to CPU's as early as possible. No functional change if no
1159           microcode data is glued to the initrd, therefore it's safe to say Y.
1160 
1161 config X86_MSR
1162         tristate "/dev/cpu/*/msr - Model-specific register support"
1163         ---help---
1164           This device gives privileged processes access to the x86
1165           Model-Specific Registers (MSRs).  It is a character device with
1166           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1167           MSR accesses are directed to a specific CPU on multi-processor
1168           systems.
1169 
1170 config X86_CPUID
1171         tristate "/dev/cpu/*/cpuid - CPU information support"
1172         ---help---
1173           This device gives processes access to the x86 CPUID instruction to
1174           be executed on a specific processor.  It is a character device
1175           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1176           /dev/cpu/31/cpuid.
1177 
1178 choice
1179         prompt "High Memory Support"
1180         default HIGHMEM4G
1181         depends on X86_32
1182 
1183 config NOHIGHMEM
1184         bool "off"
1185         ---help---
1186           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1187           However, the address space of 32-bit x86 processors is only 4
1188           Gigabytes large. That means that, if you have a large amount of
1189           physical memory, not all of it can be "permanently mapped" by the
1190           kernel. The physical memory that's not permanently mapped is called
1191           "high memory".
1192 
1193           If you are compiling a kernel which will never run on a machine with
1194           more than 1 Gigabyte total physical RAM, answer "off" here (default
1195           choice and suitable for most users). This will result in a "3GB/1GB"
1196           split: 3GB are mapped so that each process sees a 3GB virtual memory
1197           space and the remaining part of the 4GB virtual memory space is used
1198           by the kernel to permanently map as much physical memory as
1199           possible.
1200 
1201           If the machine has between 1 and 4 Gigabytes physical RAM, then
1202           answer "4GB" here.
1203 
1204           If more than 4 Gigabytes is used then answer "64GB" here. This
1205           selection turns Intel PAE (Physical Address Extension) mode on.
1206           PAE implements 3-level paging on IA32 processors. PAE is fully
1207           supported by Linux, PAE mode is implemented on all recent Intel
1208           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1209           then the kernel will not boot on CPUs that don't support PAE!
1210 
1211           The actual amount of total physical memory will either be
1212           auto detected or can be forced by using a kernel command line option
1213           such as "mem=256M". (Try "man bootparam" or see the documentation of
1214           your boot loader (lilo or loadlin) about how to pass options to the
1215           kernel at boot time.)
1216 
1217           If unsure, say "off".
1218 
1219 config HIGHMEM4G
1220         bool "4GB"
1221         ---help---
1222           Select this if you have a 32-bit processor and between 1 and 4
1223           gigabytes of physical RAM.
1224 
1225 config HIGHMEM64G
1226         bool "64GB"
1227         depends on !M486
1228         select X86_PAE
1229         ---help---
1230           Select this if you have a 32-bit processor and more than 4
1231           gigabytes of physical RAM.
1232 
1233 endchoice
1234 
1235 choice
1236         prompt "Memory split" if EXPERT
1237         default VMSPLIT_3G
1238         depends on X86_32
1239         ---help---
1240           Select the desired split between kernel and user memory.
1241 
1242           If the address range available to the kernel is less than the
1243           physical memory installed, the remaining memory will be available
1244           as "high memory". Accessing high memory is a little more costly
1245           than low memory, as it needs to be mapped into the kernel first.
1246           Note that increasing the kernel address space limits the range
1247           available to user programs, making the address space there
1248           tighter.  Selecting anything other than the default 3G/1G split
1249           will also likely make your kernel incompatible with binary-only
1250           kernel modules.
1251 
1252           If you are not absolutely sure what you are doing, leave this
1253           option alone!
1254 
1255         config VMSPLIT_3G
1256                 bool "3G/1G user/kernel split"
1257         config VMSPLIT_3G_OPT
1258                 depends on !X86_PAE
1259                 bool "3G/1G user/kernel split (for full 1G low memory)"
1260         config VMSPLIT_2G
1261                 bool "2G/2G user/kernel split"
1262         config VMSPLIT_2G_OPT
1263                 depends on !X86_PAE
1264                 bool "2G/2G user/kernel split (for full 2G low memory)"
1265         config VMSPLIT_1G
1266                 bool "1G/3G user/kernel split"
1267 endchoice
1268 
1269 config PAGE_OFFSET
1270         hex
1271         default 0xB0000000 if VMSPLIT_3G_OPT
1272         default 0x80000000 if VMSPLIT_2G
1273         default 0x78000000 if VMSPLIT_2G_OPT
1274         default 0x40000000 if VMSPLIT_1G
1275         default 0xC0000000
1276         depends on X86_32
1277 
1278 config HIGHMEM
1279         def_bool y
1280         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1281 
1282 config X86_PAE
1283         bool "PAE (Physical Address Extension) Support"
1284         depends on X86_32 && !HIGHMEM4G
1285         ---help---
1286           PAE is required for NX support, and furthermore enables
1287           larger swapspace support for non-overcommit purposes. It
1288           has the cost of more pagetable lookup overhead, and also
1289           consumes more pagetable space per process.
1290 
1291 config ARCH_PHYS_ADDR_T_64BIT
1292         def_bool y
1293         depends on X86_64 || X86_PAE
1294 
1295 config ARCH_DMA_ADDR_T_64BIT
1296         def_bool y
1297         depends on X86_64 || HIGHMEM64G
1298 
1299 config X86_DIRECT_GBPAGES
1300         def_bool y
1301         depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1302         ---help---
1303           Certain kernel features effectively disable kernel
1304           linear 1 GB mappings (even if the CPU otherwise
1305           supports them), so don't confuse the user by printing
1306           that we have them enabled.
1307 
1308 # Common NUMA Features
1309 config NUMA
1310         bool "Numa Memory Allocation and Scheduler Support"
1311         depends on SMP
1312         depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1313         default y if X86_BIGSMP
1314         ---help---
1315           Enable NUMA (Non Uniform Memory Access) support.
1316 
1317           The kernel will try to allocate memory used by a CPU on the
1318           local memory controller of the CPU and add some more
1319           NUMA awareness to the kernel.
1320 
1321           For 64-bit this is recommended if the system is Intel Core i7
1322           (or later), AMD Opteron, or EM64T NUMA.
1323 
1324           For 32-bit this is only needed if you boot a 32-bit
1325           kernel on a 64-bit NUMA platform.
1326 
1327           Otherwise, you should say N.
1328 
1329 config AMD_NUMA
1330         def_bool y
1331         prompt "Old style AMD Opteron NUMA detection"
1332         depends on X86_64 && NUMA && PCI
1333         ---help---
1334           Enable AMD NUMA node topology detection.  You should say Y here if
1335           you have a multi processor AMD system. This uses an old method to
1336           read the NUMA configuration directly from the builtin Northbridge
1337           of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1338           which also takes priority if both are compiled in.
1339 
1340 config X86_64_ACPI_NUMA
1341         def_bool y
1342         prompt "ACPI NUMA detection"
1343         depends on X86_64 && NUMA && ACPI && PCI
1344         select ACPI_NUMA
1345         ---help---
1346           Enable ACPI SRAT based node topology detection.
1347 
1348 # Some NUMA nodes have memory ranges that span
1349 # other nodes.  Even though a pfn is valid and
1350 # between a node's start and end pfns, it may not
1351 # reside on that node.  See memmap_init_zone()
1352 # for details.
1353 config NODES_SPAN_OTHER_NODES
1354         def_bool y
1355         depends on X86_64_ACPI_NUMA
1356 
1357 config NUMA_EMU
1358         bool "NUMA emulation"
1359         depends on NUMA
1360         ---help---
1361           Enable NUMA emulation. A flat machine will be split
1362           into virtual nodes when booted with "numa=fake=N", where N is the
1363           number of nodes. This is only useful for debugging.
1364 
1365 config NODES_SHIFT
1366         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1367         range 1 10
1368         default "10" if MAXSMP
1369         default "6" if X86_64
1370         default "3"
1371         depends on NEED_MULTIPLE_NODES
1372         ---help---
1373           Specify the maximum number of NUMA Nodes available on the target
1374           system.  Increases memory reserved to accommodate various tables.
1375 
1376 config ARCH_HAVE_MEMORY_PRESENT
1377         def_bool y
1378         depends on X86_32 && DISCONTIGMEM
1379 
1380 config NEED_NODE_MEMMAP_SIZE
1381         def_bool y
1382         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1383 
1384 config ARCH_FLATMEM_ENABLE
1385         def_bool y
1386         depends on X86_32 && !NUMA
1387 
1388 config ARCH_DISCONTIGMEM_ENABLE
1389         def_bool y
1390         depends on NUMA && X86_32
1391 
1392 config ARCH_DISCONTIGMEM_DEFAULT
1393         def_bool y
1394         depends on NUMA && X86_32
1395 
1396 config ARCH_SPARSEMEM_ENABLE
1397         def_bool y
1398         depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1399         select SPARSEMEM_STATIC if X86_32
1400         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1401 
1402 config ARCH_SPARSEMEM_DEFAULT
1403         def_bool y
1404         depends on X86_64
1405 
1406 config ARCH_SELECT_MEMORY_MODEL
1407         def_bool y
1408         depends on ARCH_SPARSEMEM_ENABLE
1409 
1410 config ARCH_MEMORY_PROBE
1411         bool "Enable sysfs memory/probe interface"
1412         depends on X86_64 && MEMORY_HOTPLUG
1413         help
1414           This option enables a sysfs memory/probe interface for testing.
1415           See Documentation/memory-hotplug.txt for more information.
1416           If you are unsure how to answer this question, answer N.
1417 
1418 config ARCH_PROC_KCORE_TEXT
1419         def_bool y
1420         depends on X86_64 && PROC_KCORE
1421 
1422 config ILLEGAL_POINTER_VALUE
1423        hex
1424        default 0 if X86_32
1425        default 0xdead000000000000 if X86_64
1426 
1427 source "mm/Kconfig"
1428 
1429 config X86_PMEM_LEGACY
1430         bool "Support non-standard NVDIMMs and ADR protected memory"
1431         depends on PHYS_ADDR_T_64BIT
1432         depends on BLK_DEV
1433         select LIBNVDIMM
1434         help
1435           Treat memory marked using the non-standard e820 type of 12 as used
1436           by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1437           The kernel will offer these regions to the 'pmem' driver so
1438           they can be used for persistent storage.
1439 
1440           Say Y if unsure.
1441 
1442 config HIGHPTE
1443         bool "Allocate 3rd-level pagetables from highmem"
1444         depends on HIGHMEM
1445         ---help---
1446           The VM uses one page table entry for each page of physical memory.
1447           For systems with a lot of RAM, this can be wasteful of precious
1448           low memory.  Setting this option will put user-space page table
1449           entries in high memory.
1450 
1451 config X86_CHECK_BIOS_CORRUPTION
1452         bool "Check for low memory corruption"
1453         ---help---
1454           Periodically check for memory corruption in low memory, which
1455           is suspected to be caused by BIOS.  Even when enabled in the
1456           configuration, it is disabled at runtime.  Enable it by
1457           setting "memory_corruption_check=1" on the kernel command
1458           line.  By default it scans the low 64k of memory every 60
1459           seconds; see the memory_corruption_check_size and
1460           memory_corruption_check_period parameters in
1461           Documentation/kernel-parameters.txt to adjust this.
1462 
1463           When enabled with the default parameters, this option has
1464           almost no overhead, as it reserves a relatively small amount
1465           of memory and scans it infrequently.  It both detects corruption
1466           and prevents it from affecting the running system.
1467 
1468           It is, however, intended as a diagnostic tool; if repeatable
1469           BIOS-originated corruption always affects the same memory,
1470           you can use memmap= to prevent the kernel from using that
1471           memory.
1472 
1473 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1474         bool "Set the default setting of memory_corruption_check"
1475         depends on X86_CHECK_BIOS_CORRUPTION
1476         default y
1477         ---help---
1478           Set whether the default state of memory_corruption_check is
1479           on or off.
1480 
1481 config X86_RESERVE_LOW
1482         int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1483         default 64
1484         range 4 640
1485         ---help---
1486           Specify the amount of low memory to reserve for the BIOS.
1487 
1488           The first page contains BIOS data structures that the kernel
1489           must not use, so that page must always be reserved.
1490 
1491           By default we reserve the first 64K of physical RAM, as a
1492           number of BIOSes are known to corrupt that memory range
1493           during events such as suspend/resume or monitor cable
1494           insertion, so it must not be used by the kernel.
1495 
1496           You can set this to 4 if you are absolutely sure that you
1497           trust the BIOS to get all its memory reservations and usages
1498           right.  If you know your BIOS have problems beyond the
1499           default 64K area, you can set this to 640 to avoid using the
1500           entire low memory range.
1501 
1502           If you have doubts about the BIOS (e.g. suspend/resume does
1503           not work or there's kernel crashes after certain hardware
1504           hotplug events) then you might want to enable
1505           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1506           typical corruption patterns.
1507 
1508           Leave this to the default value of 64 if you are unsure.
1509 
1510 config MATH_EMULATION
1511         bool
1512         prompt "Math emulation" if X86_32
1513         ---help---
1514           Linux can emulate a math coprocessor (used for floating point
1515           operations) if you don't have one. 486DX and Pentium processors have
1516           a math coprocessor built in, 486SX and 386 do not, unless you added
1517           a 487DX or 387, respectively. (The messages during boot time can
1518           give you some hints here ["man dmesg"].) Everyone needs either a
1519           coprocessor or this emulation.
1520 
1521           If you don't have a math coprocessor, you need to say Y here; if you
1522           say Y here even though you have a coprocessor, the coprocessor will
1523           be used nevertheless. (This behavior can be changed with the kernel
1524           command line option "no387", which comes handy if your coprocessor
1525           is broken. Try "man bootparam" or see the documentation of your boot
1526           loader (lilo or loadlin) about how to pass options to the kernel at
1527           boot time.) This means that it is a good idea to say Y here if you
1528           intend to use this kernel on different machines.
1529 
1530           More information about the internals of the Linux math coprocessor
1531           emulation can be found in <file:arch/x86/math-emu/README>.
1532 
1533           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1534           kernel, it won't hurt.
1535 
1536 config MTRR
1537         def_bool y
1538         prompt "MTRR (Memory Type Range Register) support" if EXPERT
1539         ---help---
1540           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1541           the Memory Type Range Registers (MTRRs) may be used to control
1542           processor access to memory ranges. This is most useful if you have
1543           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1544           allows bus write transfers to be combined into a larger transfer
1545           before bursting over the PCI/AGP bus. This can increase performance
1546           of image write operations 2.5 times or more. Saying Y here creates a
1547           /proc/mtrr file which may be used to manipulate your processor's
1548           MTRRs. Typically the X server should use this.
1549 
1550           This code has a reasonably generic interface so that similar
1551           control registers on other processors can be easily supported
1552           as well:
1553 
1554           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1555           Registers (ARRs) which provide a similar functionality to MTRRs. For
1556           these, the ARRs are used to emulate the MTRRs.
1557           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1558           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1559           write-combining. All of these processors are supported by this code
1560           and it makes sense to say Y here if you have one of them.
1561 
1562           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1563           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1564           can lead to all sorts of problems, so it's good to say Y here.
1565 
1566           You can safely say Y even if your machine doesn't have MTRRs, you'll
1567           just add about 9 KB to your kernel.
1568 
1569           See <file:Documentation/x86/mtrr.txt> for more information.
1570 
1571 config MTRR_SANITIZER
1572         def_bool y
1573         prompt "MTRR cleanup support"
1574         depends on MTRR
1575         ---help---
1576           Convert MTRR layout from continuous to discrete, so X drivers can
1577           add writeback entries.
1578 
1579           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1580           The largest mtrr entry size for a continuous block can be set with
1581           mtrr_chunk_size.
1582 
1583           If unsure, say Y.
1584 
1585 config MTRR_SANITIZER_ENABLE_DEFAULT
1586         int "MTRR cleanup enable value (0-1)"
1587         range 0 1
1588         default "0"
1589         depends on MTRR_SANITIZER
1590         ---help---
1591           Enable mtrr cleanup default value
1592 
1593 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1594         int "MTRR cleanup spare reg num (0-7)"
1595         range 0 7
1596         default "1"
1597         depends on MTRR_SANITIZER
1598         ---help---
1599           mtrr cleanup spare entries default, it can be changed via
1600           mtrr_spare_reg_nr=N on the kernel command line.
1601 
1602 config X86_PAT
1603         def_bool y
1604         prompt "x86 PAT support" if EXPERT
1605         depends on MTRR
1606         ---help---
1607           Use PAT attributes to setup page level cache control.
1608 
1609           PATs are the modern equivalents of MTRRs and are much more
1610           flexible than MTRRs.
1611 
1612           Say N here if you see bootup problems (boot crash, boot hang,
1613           spontaneous reboots) or a non-working video driver.
1614 
1615           If unsure, say Y.
1616 
1617 config ARCH_USES_PG_UNCACHED
1618         def_bool y
1619         depends on X86_PAT
1620 
1621 config ARCH_RANDOM
1622         def_bool y
1623         prompt "x86 architectural random number generator" if EXPERT
1624         ---help---
1625           Enable the x86 architectural RDRAND instruction
1626           (Intel Bull Mountain technology) to generate random numbers.
1627           If supported, this is a high bandwidth, cryptographically
1628           secure hardware random number generator.
1629 
1630 config X86_SMAP
1631         def_bool y
1632         prompt "Supervisor Mode Access Prevention" if EXPERT
1633         ---help---
1634           Supervisor Mode Access Prevention (SMAP) is a security
1635           feature in newer Intel processors.  There is a small
1636           performance cost if this enabled and turned on; there is
1637           also a small increase in the kernel size if this is enabled.
1638 
1639           If unsure, say Y.
1640 
1641 config X86_INTEL_MPX
1642         prompt "Intel MPX (Memory Protection Extensions)"
1643         def_bool n
1644         depends on CPU_SUP_INTEL
1645         ---help---
1646           MPX provides hardware features that can be used in
1647           conjunction with compiler-instrumented code to check
1648           memory references.  It is designed to detect buffer
1649           overflow or underflow bugs.
1650 
1651           This option enables running applications which are
1652           instrumented or otherwise use MPX.  It does not use MPX
1653           itself inside the kernel or to protect the kernel
1654           against bad memory references.
1655 
1656           Enabling this option will make the kernel larger:
1657           ~8k of kernel text and 36 bytes of data on a 64-bit
1658           defconfig.  It adds a long to the 'mm_struct' which
1659           will increase the kernel memory overhead of each
1660           process and adds some branches to paths used during
1661           exec() and munmap().
1662 
1663           For details, see Documentation/x86/intel_mpx.txt
1664 
1665           If unsure, say N.
1666 
1667 config EFI
1668         bool "EFI runtime service support"
1669         depends on ACPI
1670         select UCS2_STRING
1671         select EFI_RUNTIME_WRAPPERS
1672         ---help---
1673           This enables the kernel to use EFI runtime services that are
1674           available (such as the EFI variable services).
1675 
1676           This option is only useful on systems that have EFI firmware.
1677           In addition, you should use the latest ELILO loader available
1678           at <http://elilo.sourceforge.net> in order to take advantage
1679           of EFI runtime services. However, even with this option, the
1680           resultant kernel should continue to boot on existing non-EFI
1681           platforms.
1682 
1683 config EFI_STUB
1684        bool "EFI stub support"
1685        depends on EFI && !X86_USE_3DNOW
1686        select RELOCATABLE
1687        ---help---
1688           This kernel feature allows a bzImage to be loaded directly
1689           by EFI firmware without the use of a bootloader.
1690 
1691           See Documentation/efi-stub.txt for more information.
1692 
1693 config EFI_MIXED
1694         bool "EFI mixed-mode support"
1695         depends on EFI_STUB && X86_64
1696         ---help---
1697            Enabling this feature allows a 64-bit kernel to be booted
1698            on a 32-bit firmware, provided that your CPU supports 64-bit
1699            mode.
1700 
1701            Note that it is not possible to boot a mixed-mode enabled
1702            kernel via the EFI boot stub - a bootloader that supports
1703            the EFI handover protocol must be used.
1704 
1705            If unsure, say N.
1706 
1707 config SECCOMP
1708         def_bool y
1709         prompt "Enable seccomp to safely compute untrusted bytecode"
1710         ---help---
1711           This kernel feature is useful for number crunching applications
1712           that may need to compute untrusted bytecode during their
1713           execution. By using pipes or other transports made available to
1714           the process as file descriptors supporting the read/write
1715           syscalls, it's possible to isolate those applications in
1716           their own address space using seccomp. Once seccomp is
1717           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1718           and the task is only allowed to execute a few safe syscalls
1719           defined by each seccomp mode.
1720 
1721           If unsure, say Y. Only embedded should say N here.
1722 
1723 source kernel/Kconfig.hz
1724 
1725 config KEXEC
1726         bool "kexec system call"
1727         ---help---
1728           kexec is a system call that implements the ability to shutdown your
1729           current kernel, and to start another kernel.  It is like a reboot
1730           but it is independent of the system firmware.   And like a reboot
1731           you can start any kernel with it, not just Linux.
1732 
1733           The name comes from the similarity to the exec system call.
1734 
1735           It is an ongoing process to be certain the hardware in a machine
1736           is properly shutdown, so do not be surprised if this code does not
1737           initially work for you.  As of this writing the exact hardware
1738           interface is strongly in flux, so no good recommendation can be
1739           made.
1740 
1741 config KEXEC_FILE
1742         bool "kexec file based system call"
1743         select BUILD_BIN2C
1744         depends on KEXEC
1745         depends on X86_64
1746         depends on CRYPTO=y
1747         depends on CRYPTO_SHA256=y
1748         ---help---
1749           This is new version of kexec system call. This system call is
1750           file based and takes file descriptors as system call argument
1751           for kernel and initramfs as opposed to list of segments as
1752           accepted by previous system call.
1753 
1754 config KEXEC_VERIFY_SIG
1755         bool "Verify kernel signature during kexec_file_load() syscall"
1756         depends on KEXEC_FILE
1757         ---help---
1758           This option makes kernel signature verification mandatory for
1759           the kexec_file_load() syscall.
1760 
1761           In addition to that option, you need to enable signature
1762           verification for the corresponding kernel image type being
1763           loaded in order for this to work.
1764 
1765 config KEXEC_BZIMAGE_VERIFY_SIG
1766         bool "Enable bzImage signature verification support"
1767         depends on KEXEC_VERIFY_SIG
1768         depends on SIGNED_PE_FILE_VERIFICATION
1769         select SYSTEM_TRUSTED_KEYRING
1770         ---help---
1771           Enable bzImage signature verification support.
1772 
1773 config CRASH_DUMP
1774         bool "kernel crash dumps"
1775         depends on X86_64 || (X86_32 && HIGHMEM)
1776         ---help---
1777           Generate crash dump after being started by kexec.
1778           This should be normally only set in special crash dump kernels
1779           which are loaded in the main kernel with kexec-tools into
1780           a specially reserved region and then later executed after
1781           a crash by kdump/kexec. The crash dump kernel must be compiled
1782           to a memory address not used by the main kernel or BIOS using
1783           PHYSICAL_START, or it must be built as a relocatable image
1784           (CONFIG_RELOCATABLE=y).
1785           For more details see Documentation/kdump/kdump.txt
1786 
1787 config KEXEC_JUMP
1788         bool "kexec jump"
1789         depends on KEXEC && HIBERNATION
1790         ---help---
1791           Jump between original kernel and kexeced kernel and invoke
1792           code in physical address mode via KEXEC
1793 
1794 config PHYSICAL_START
1795         hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1796         default "0x1000000"
1797         ---help---
1798           This gives the physical address where the kernel is loaded.
1799 
1800           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1801           bzImage will decompress itself to above physical address and
1802           run from there. Otherwise, bzImage will run from the address where
1803           it has been loaded by the boot loader and will ignore above physical
1804           address.
1805 
1806           In normal kdump cases one does not have to set/change this option
1807           as now bzImage can be compiled as a completely relocatable image
1808           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1809           address. This option is mainly useful for the folks who don't want
1810           to use a bzImage for capturing the crash dump and want to use a
1811           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1812           to be specifically compiled to run from a specific memory area
1813           (normally a reserved region) and this option comes handy.
1814 
1815           So if you are using bzImage for capturing the crash dump,
1816           leave the value here unchanged to 0x1000000 and set
1817           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1818           for capturing the crash dump change this value to start of
1819           the reserved region.  In other words, it can be set based on
1820           the "X" value as specified in the "crashkernel=YM@XM"
1821           command line boot parameter passed to the panic-ed
1822           kernel. Please take a look at Documentation/kdump/kdump.txt
1823           for more details about crash dumps.
1824 
1825           Usage of bzImage for capturing the crash dump is recommended as
1826           one does not have to build two kernels. Same kernel can be used
1827           as production kernel and capture kernel. Above option should have
1828           gone away after relocatable bzImage support is introduced. But it
1829           is present because there are users out there who continue to use
1830           vmlinux for dump capture. This option should go away down the
1831           line.
1832 
1833           Don't change this unless you know what you are doing.
1834 
1835 config RELOCATABLE
1836         bool "Build a relocatable kernel"
1837         default y
1838         ---help---
1839           This builds a kernel image that retains relocation information
1840           so it can be loaded someplace besides the default 1MB.
1841           The relocations tend to make the kernel binary about 10% larger,
1842           but are discarded at runtime.
1843 
1844           One use is for the kexec on panic case where the recovery kernel
1845           must live at a different physical address than the primary
1846           kernel.
1847 
1848           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1849           it has been loaded at and the compile time physical address
1850           (CONFIG_PHYSICAL_START) is used as the minimum location.
1851 
1852 config RANDOMIZE_BASE
1853         bool "Randomize the address of the kernel image"
1854         depends on RELOCATABLE
1855         default n
1856         ---help---
1857            Randomizes the physical and virtual address at which the
1858            kernel image is decompressed, as a security feature that
1859            deters exploit attempts relying on knowledge of the location
1860            of kernel internals.
1861 
1862            Entropy is generated using the RDRAND instruction if it is
1863            supported. If RDTSC is supported, it is used as well. If
1864            neither RDRAND nor RDTSC are supported, then randomness is
1865            read from the i8254 timer.
1866 
1867            The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1868            and aligned according to PHYSICAL_ALIGN. Since the kernel is
1869            built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1870            minimum of 2MiB, only 10 bits of entropy is theoretically
1871            possible. At best, due to page table layouts, 64-bit can use
1872            9 bits of entropy and 32-bit uses 8 bits.
1873 
1874            If unsure, say N.
1875 
1876 config RANDOMIZE_BASE_MAX_OFFSET
1877         hex "Maximum kASLR offset allowed" if EXPERT
1878         depends on RANDOMIZE_BASE
1879         range 0x0 0x20000000 if X86_32
1880         default "0x20000000" if X86_32
1881         range 0x0 0x40000000 if X86_64
1882         default "0x40000000" if X86_64
1883         ---help---
1884           The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1885           memory is used to determine the maximal offset in bytes that will
1886           be applied to the kernel when kernel Address Space Layout
1887           Randomization (kASLR) is active. This must be a multiple of
1888           PHYSICAL_ALIGN.
1889 
1890           On 32-bit this is limited to 512MiB by page table layouts. The
1891           default is 512MiB.
1892 
1893           On 64-bit this is limited by how the kernel fixmap page table is
1894           positioned, so this cannot be larger than 1GiB currently. Without
1895           RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1896           and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1897           modules area will shrink to compensate, up to the current maximum
1898           1GiB to 1GiB split. The default is 1GiB.
1899 
1900           If unsure, leave at the default value.
1901 
1902 # Relocation on x86 needs some additional build support
1903 config X86_NEED_RELOCS
1904         def_bool y
1905         depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1906 
1907 config PHYSICAL_ALIGN
1908         hex "Alignment value to which kernel should be aligned"
1909         default "0x200000"
1910         range 0x2000 0x1000000 if X86_32
1911         range 0x200000 0x1000000 if X86_64
1912         ---help---
1913           This value puts the alignment restrictions on physical address
1914           where kernel is loaded and run from. Kernel is compiled for an
1915           address which meets above alignment restriction.
1916 
1917           If bootloader loads the kernel at a non-aligned address and
1918           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1919           address aligned to above value and run from there.
1920 
1921           If bootloader loads the kernel at a non-aligned address and
1922           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1923           load address and decompress itself to the address it has been
1924           compiled for and run from there. The address for which kernel is
1925           compiled already meets above alignment restrictions. Hence the
1926           end result is that kernel runs from a physical address meeting
1927           above alignment restrictions.
1928 
1929           On 32-bit this value must be a multiple of 0x2000. On 64-bit
1930           this value must be a multiple of 0x200000.
1931 
1932           Don't change this unless you know what you are doing.
1933 
1934 config HOTPLUG_CPU
1935         bool "Support for hot-pluggable CPUs"
1936         depends on SMP
1937         ---help---
1938           Say Y here to allow turning CPUs off and on. CPUs can be
1939           controlled through /sys/devices/system/cpu.
1940           ( Note: power management support will enable this option
1941             automatically on SMP systems. )
1942           Say N if you want to disable CPU hotplug.
1943 
1944 config BOOTPARAM_HOTPLUG_CPU0
1945         bool "Set default setting of cpu0_hotpluggable"
1946         default n
1947         depends on HOTPLUG_CPU
1948         ---help---
1949           Set whether default state of cpu0_hotpluggable is on or off.
1950 
1951           Say Y here to enable CPU0 hotplug by default. If this switch
1952           is turned on, there is no need to give cpu0_hotplug kernel
1953           parameter and the CPU0 hotplug feature is enabled by default.
1954 
1955           Please note: there are two known CPU0 dependencies if you want
1956           to enable the CPU0 hotplug feature either by this switch or by
1957           cpu0_hotplug kernel parameter.
1958 
1959           First, resume from hibernate or suspend always starts from CPU0.
1960           So hibernate and suspend are prevented if CPU0 is offline.
1961 
1962           Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1963           offline if any interrupt can not migrate out of CPU0. There may
1964           be other CPU0 dependencies.
1965 
1966           Please make sure the dependencies are under your control before
1967           you enable this feature.
1968 
1969           Say N if you don't want to enable CPU0 hotplug feature by default.
1970           You still can enable the CPU0 hotplug feature at boot by kernel
1971           parameter cpu0_hotplug.
1972 
1973 config DEBUG_HOTPLUG_CPU0
1974         def_bool n
1975         prompt "Debug CPU0 hotplug"
1976         depends on HOTPLUG_CPU
1977         ---help---
1978           Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1979           soon as possible and boots up userspace with CPU0 offlined. User
1980           can online CPU0 back after boot time.
1981 
1982           To debug CPU0 hotplug, you need to enable CPU0 offline/online
1983           feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1984           compilation or giving cpu0_hotplug kernel parameter at boot.
1985 
1986           If unsure, say N.
1987 
1988 config COMPAT_VDSO
1989         def_bool n
1990         prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1991         depends on X86_32 || IA32_EMULATION
1992         ---help---
1993           Certain buggy versions of glibc will crash if they are
1994           presented with a 32-bit vDSO that is not mapped at the address
1995           indicated in its segment table.
1996 
1997           The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1998           and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1999           49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
2000           the only released version with the bug, but OpenSUSE 9
2001           contains a buggy "glibc 2.3.2".
2002 
2003           The symptom of the bug is that everything crashes on startup, saying:
2004           dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2005 
2006           Saying Y here changes the default value of the vdso32 boot
2007           option from 1 to 0, which turns off the 32-bit vDSO entirely.
2008           This works around the glibc bug but hurts performance.
2009 
2010           If unsure, say N: if you are compiling your own kernel, you
2011           are unlikely to be using a buggy version of glibc.
2012 
2013 config CMDLINE_BOOL
2014         bool "Built-in kernel command line"
2015         ---help---
2016           Allow for specifying boot arguments to the kernel at
2017           build time.  On some systems (e.g. embedded ones), it is
2018           necessary or convenient to provide some or all of the
2019           kernel boot arguments with the kernel itself (that is,
2020           to not rely on the boot loader to provide them.)
2021 
2022           To compile command line arguments into the kernel,
2023           set this option to 'Y', then fill in the
2024           boot arguments in CONFIG_CMDLINE.
2025 
2026           Systems with fully functional boot loaders (i.e. non-embedded)
2027           should leave this option set to 'N'.
2028 
2029 config CMDLINE
2030         string "Built-in kernel command string"
2031         depends on CMDLINE_BOOL
2032         default ""
2033         ---help---
2034           Enter arguments here that should be compiled into the kernel
2035           image and used at boot time.  If the boot loader provides a
2036           command line at boot time, it is appended to this string to
2037           form the full kernel command line, when the system boots.
2038 
2039           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2040           change this behavior.
2041 
2042           In most cases, the command line (whether built-in or provided
2043           by the boot loader) should specify the device for the root
2044           file system.
2045 
2046 config CMDLINE_OVERRIDE
2047         bool "Built-in command line overrides boot loader arguments"
2048         depends on CMDLINE_BOOL
2049         ---help---
2050           Set this option to 'Y' to have the kernel ignore the boot loader
2051           command line, and use ONLY the built-in command line.
2052 
2053           This is used to work around broken boot loaders.  This should
2054           be set to 'N' under normal conditions.
2055 
2056 source "kernel/livepatch/Kconfig"
2057 
2058 endmenu
2059 
2060 config ARCH_ENABLE_MEMORY_HOTPLUG
2061         def_bool y
2062         depends on X86_64 || (X86_32 && HIGHMEM)
2063 
2064 config ARCH_ENABLE_MEMORY_HOTREMOVE
2065         def_bool y
2066         depends on MEMORY_HOTPLUG
2067 
2068 config USE_PERCPU_NUMA_NODE_ID
2069         def_bool y
2070         depends on NUMA
2071 
2072 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2073         def_bool y
2074         depends on X86_64 || X86_PAE
2075 
2076 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2077         def_bool y
2078         depends on X86_64 && HUGETLB_PAGE && MIGRATION
2079 
2080 menu "Power management and ACPI options"
2081 
2082 config ARCH_HIBERNATION_HEADER
2083         def_bool y
2084         depends on X86_64 && HIBERNATION
2085 
2086 source "kernel/power/Kconfig"
2087 
2088 source "drivers/acpi/Kconfig"
2089 
2090 source "drivers/sfi/Kconfig"
2091 
2092 config X86_APM_BOOT
2093         def_bool y
2094         depends on APM
2095 
2096 menuconfig APM
2097         tristate "APM (Advanced Power Management) BIOS support"
2098         depends on X86_32 && PM_SLEEP
2099         ---help---
2100           APM is a BIOS specification for saving power using several different
2101           techniques. This is mostly useful for battery powered laptops with
2102           APM compliant BIOSes. If you say Y here, the system time will be
2103           reset after a RESUME operation, the /proc/apm device will provide
2104           battery status information, and user-space programs will receive
2105           notification of APM "events" (e.g. battery status change).
2106 
2107           If you select "Y" here, you can disable actual use of the APM
2108           BIOS by passing the "apm=off" option to the kernel at boot time.
2109 
2110           Note that the APM support is almost completely disabled for
2111           machines with more than one CPU.
2112 
2113           In order to use APM, you will need supporting software. For location
2114           and more information, read <file:Documentation/power/apm-acpi.txt>
2115           and the Battery Powered Linux mini-HOWTO, available from
2116           <http://www.tldp.org/docs.html#howto>.
2117 
2118           This driver does not spin down disk drives (see the hdparm(8)
2119           manpage ("man 8 hdparm") for that), and it doesn't turn off
2120           VESA-compliant "green" monitors.
2121 
2122           This driver does not support the TI 4000M TravelMate and the ACER
2123           486/DX4/75 because they don't have compliant BIOSes. Many "green"
2124           desktop machines also don't have compliant BIOSes, and this driver
2125           may cause those machines to panic during the boot phase.
2126 
2127           Generally, if you don't have a battery in your machine, there isn't
2128           much point in using this driver and you should say N. If you get
2129           random kernel OOPSes or reboots that don't seem to be related to
2130           anything, try disabling/enabling this option (or disabling/enabling
2131           APM in your BIOS).
2132 
2133           Some other things you should try when experiencing seemingly random,
2134           "weird" problems:
2135 
2136           1) make sure that you have enough swap space and that it is
2137           enabled.
2138           2) pass the "no-hlt" option to the kernel
2139           3) switch on floating point emulation in the kernel and pass
2140           the "no387" option to the kernel
2141           4) pass the "floppy=nodma" option to the kernel
2142           5) pass the "mem=4M" option to the kernel (thereby disabling
2143           all but the first 4 MB of RAM)
2144           6) make sure that the CPU is not over clocked.
2145           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2146           8) disable the cache from your BIOS settings
2147           9) install a fan for the video card or exchange video RAM
2148           10) install a better fan for the CPU
2149           11) exchange RAM chips
2150           12) exchange the motherboard.
2151 
2152           To compile this driver as a module, choose M here: the
2153           module will be called apm.
2154 
2155 if APM
2156 
2157 config APM_IGNORE_USER_SUSPEND
2158         bool "Ignore USER SUSPEND"
2159         ---help---
2160           This option will ignore USER SUSPEND requests. On machines with a
2161           compliant APM BIOS, you want to say N. However, on the NEC Versa M
2162           series notebooks, it is necessary to say Y because of a BIOS bug.
2163 
2164 config APM_DO_ENABLE
2165         bool "Enable PM at boot time"
2166         ---help---
2167           Enable APM features at boot time. From page 36 of the APM BIOS
2168           specification: "When disabled, the APM BIOS does not automatically
2169           power manage devices, enter the Standby State, enter the Suspend
2170           State, or take power saving steps in response to CPU Idle calls."
2171           This driver will make CPU Idle calls when Linux is idle (unless this
2172           feature is turned off -- see "Do CPU IDLE calls", below). This
2173           should always save battery power, but more complicated APM features
2174           will be dependent on your BIOS implementation. You may need to turn
2175           this option off if your computer hangs at boot time when using APM
2176           support, or if it beeps continuously instead of suspending. Turn
2177           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2178           T400CDT. This is off by default since most machines do fine without
2179           this feature.
2180 
2181 config APM_CPU_IDLE
2182         depends on CPU_IDLE
2183         bool "Make CPU Idle calls when idle"
2184         ---help---
2185           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2186           On some machines, this can activate improved power savings, such as
2187           a slowed CPU clock rate, when the machine is idle. These idle calls
2188           are made after the idle loop has run for some length of time (e.g.,
2189           333 mS). On some machines, this will cause a hang at boot time or
2190           whenever the CPU becomes idle. (On machines with more than one CPU,
2191           this option does nothing.)
2192 
2193 config APM_DISPLAY_BLANK
2194         bool "Enable console blanking using APM"
2195         ---help---
2196           Enable console blanking using the APM. Some laptops can use this to
2197           turn off the LCD backlight when the screen blanker of the Linux
2198           virtual console blanks the screen. Note that this is only used by
2199           the virtual console screen blanker, and won't turn off the backlight
2200           when using the X Window system. This also doesn't have anything to
2201           do with your VESA-compliant power-saving monitor. Further, this
2202           option doesn't work for all laptops -- it might not turn off your
2203           backlight at all, or it might print a lot of errors to the console,
2204           especially if you are using gpm.
2205 
2206 config APM_ALLOW_INTS
2207         bool "Allow interrupts during APM BIOS calls"
2208         ---help---
2209           Normally we disable external interrupts while we are making calls to
2210           the APM BIOS as a measure to lessen the effects of a badly behaving
2211           BIOS implementation.  The BIOS should reenable interrupts if it
2212           needs to.  Unfortunately, some BIOSes do not -- especially those in
2213           many of the newer IBM Thinkpads.  If you experience hangs when you
2214           suspend, try setting this to Y.  Otherwise, say N.
2215 
2216 endif # APM
2217 
2218 source "drivers/cpufreq/Kconfig"
2219 
2220 source "drivers/cpuidle/Kconfig"
2221 
2222 source "drivers/idle/Kconfig"
2223 
2224 endmenu
2225 
2226 
2227 menu "Bus options (PCI etc.)"
2228 
2229 config PCI
2230         bool "PCI support"
2231         default y
2232         ---help---
2233           Find out whether you have a PCI motherboard. PCI is the name of a
2234           bus system, i.e. the way the CPU talks to the other stuff inside
2235           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2236           VESA. If you have PCI, say Y, otherwise N.
2237 
2238 choice
2239         prompt "PCI access mode"
2240         depends on X86_32 && PCI
2241         default PCI_GOANY
2242         ---help---
2243           On PCI systems, the BIOS can be used to detect the PCI devices and
2244           determine their configuration. However, some old PCI motherboards
2245           have BIOS bugs and may crash if this is done. Also, some embedded
2246           PCI-based systems don't have any BIOS at all. Linux can also try to
2247           detect the PCI hardware directly without using the BIOS.
2248 
2249           With this option, you can specify how Linux should detect the
2250           PCI devices. If you choose "BIOS", the BIOS will be used,
2251           if you choose "Direct", the BIOS won't be used, and if you
2252           choose "MMConfig", then PCI Express MMCONFIG will be used.
2253           If you choose "Any", the kernel will try MMCONFIG, then the
2254           direct access method and falls back to the BIOS if that doesn't
2255           work. If unsure, go with the default, which is "Any".
2256 
2257 config PCI_GOBIOS
2258         bool "BIOS"
2259 
2260 config PCI_GOMMCONFIG
2261         bool "MMConfig"
2262 
2263 config PCI_GODIRECT
2264         bool "Direct"
2265 
2266 config PCI_GOOLPC
2267         bool "OLPC XO-1"
2268         depends on OLPC
2269 
2270 config PCI_GOANY
2271         bool "Any"
2272 
2273 endchoice
2274 
2275 config PCI_BIOS
2276         def_bool y
2277         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2278 
2279 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2280 config PCI_DIRECT
2281         def_bool y
2282         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2283 
2284 config PCI_MMCONFIG
2285         def_bool y
2286         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2287 
2288 config PCI_OLPC
2289         def_bool y
2290         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2291 
2292 config PCI_XEN
2293         def_bool y
2294         depends on PCI && XEN
2295         select SWIOTLB_XEN
2296 
2297 config PCI_DOMAINS
2298         def_bool y
2299         depends on PCI
2300 
2301 config PCI_MMCONFIG
2302         bool "Support mmconfig PCI config space access"
2303         depends on X86_64 && PCI && ACPI
2304 
2305 config PCI_CNB20LE_QUIRK
2306         bool "Read CNB20LE Host Bridge Windows" if EXPERT
2307         depends on PCI
2308         help
2309           Read the PCI windows out of the CNB20LE host bridge. This allows
2310           PCI hotplug to work on systems with the CNB20LE chipset which do
2311           not have ACPI.
2312 
2313           There's no public spec for this chipset, and this functionality
2314           is known to be incomplete.
2315 
2316           You should say N unless you know you need this.
2317 
2318 source "drivers/pci/pcie/Kconfig"
2319 
2320 source "drivers/pci/Kconfig"
2321 
2322 # x86_64 have no ISA slots, but can have ISA-style DMA.
2323 config ISA_DMA_API
2324         bool "ISA-style DMA support" if (X86_64 && EXPERT)
2325         default y
2326         help
2327           Enables ISA-style DMA support for devices requiring such controllers.
2328           If unsure, say Y.
2329 
2330 if X86_32
2331 
2332 config ISA
2333         bool "ISA support"
2334         ---help---
2335           Find out whether you have ISA slots on your motherboard.  ISA is the
2336           name of a bus system, i.e. the way the CPU talks to the other stuff
2337           inside your box.  Other bus systems are PCI, EISA, MicroChannel
2338           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2339           newer boards don't support it.  If you have ISA, say Y, otherwise N.
2340 
2341 config EISA
2342         bool "EISA support"
2343         depends on ISA
2344         ---help---
2345           The Extended Industry Standard Architecture (EISA) bus was
2346           developed as an open alternative to the IBM MicroChannel bus.
2347 
2348           The EISA bus provided some of the features of the IBM MicroChannel
2349           bus while maintaining backward compatibility with cards made for
2350           the older ISA bus.  The EISA bus saw limited use between 1988 and
2351           1995 when it was made obsolete by the PCI bus.
2352 
2353           Say Y here if you are building a kernel for an EISA-based machine.
2354 
2355           Otherwise, say N.
2356 
2357 source "drivers/eisa/Kconfig"
2358 
2359 config SCx200
2360         tristate "NatSemi SCx200 support"
2361         ---help---
2362           This provides basic support for National Semiconductor's
2363           (now AMD's) Geode processors.  The driver probes for the
2364           PCI-IDs of several on-chip devices, so its a good dependency
2365           for other scx200_* drivers.
2366 
2367           If compiled as a module, the driver is named scx200.
2368 
2369 config SCx200HR_TIMER
2370         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2371         depends on SCx200
2372         default y
2373         ---help---
2374           This driver provides a clocksource built upon the on-chip
2375           27MHz high-resolution timer.  Its also a workaround for
2376           NSC Geode SC-1100's buggy TSC, which loses time when the
2377           processor goes idle (as is done by the scheduler).  The
2378           other workaround is idle=poll boot option.
2379 
2380 config OLPC
2381         bool "One Laptop Per Child support"
2382         depends on !X86_PAE
2383         select GPIOLIB
2384         select OF
2385         select OF_PROMTREE
2386         select IRQ_DOMAIN
2387         ---help---
2388           Add support for detecting the unique features of the OLPC
2389           XO hardware.
2390 
2391 config OLPC_XO1_PM
2392         bool "OLPC XO-1 Power Management"
2393         depends on OLPC && MFD_CS5535 && PM_SLEEP
2394         select MFD_CORE
2395         ---help---
2396           Add support for poweroff and suspend of the OLPC XO-1 laptop.
2397 
2398 config OLPC_XO1_RTC
2399         bool "OLPC XO-1 Real Time Clock"
2400         depends on OLPC_XO1_PM && RTC_DRV_CMOS
2401         ---help---
2402           Add support for the XO-1 real time clock, which can be used as a
2403           programmable wakeup source.
2404 
2405 config OLPC_XO1_SCI
2406         bool "OLPC XO-1 SCI extras"
2407         depends on OLPC && OLPC_XO1_PM
2408         depends on INPUT=y
2409         select POWER_SUPPLY
2410         select GPIO_CS5535
2411         select MFD_CORE
2412         ---help---
2413           Add support for SCI-based features of the OLPC XO-1 laptop:
2414            - EC-driven system wakeups
2415            - Power button
2416            - Ebook switch
2417            - Lid switch
2418            - AC adapter status updates
2419            - Battery status updates
2420 
2421 config OLPC_XO15_SCI
2422         bool "OLPC XO-1.5 SCI extras"
2423         depends on OLPC && ACPI
2424         select POWER_SUPPLY
2425         ---help---
2426           Add support for SCI-based features of the OLPC XO-1.5 laptop:
2427            - EC-driven system wakeups
2428            - AC adapter status updates
2429            - Battery status updates
2430 
2431 config ALIX
2432         bool "PCEngines ALIX System Support (LED setup)"
2433         select GPIOLIB
2434         ---help---
2435           This option enables system support for the PCEngines ALIX.
2436           At present this just sets up LEDs for GPIO control on
2437           ALIX2/3/6 boards.  However, other system specific setup should
2438           get added here.
2439 
2440           Note: You must still enable the drivers for GPIO and LED support
2441           (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2442 
2443           Note: You have to set alix.force=1 for boards with Award BIOS.
2444 
2445 config NET5501
2446         bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2447         select GPIOLIB
2448         ---help---
2449           This option enables system support for the Soekris Engineering net5501.
2450 
2451 config GEOS
2452         bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2453         select GPIOLIB
2454         depends on DMI
2455         ---help---
2456           This option enables system support for the Traverse Technologies GEOS.
2457 
2458 config TS5500
2459         bool "Technologic Systems TS-5500 platform support"
2460         depends on MELAN
2461         select CHECK_SIGNATURE
2462         select NEW_LEDS
2463         select LEDS_CLASS
2464         ---help---
2465           This option enables system support for the Technologic Systems TS-5500.
2466 
2467 endif # X86_32
2468 
2469 config AMD_NB
2470         def_bool y
2471         depends on CPU_SUP_AMD && PCI
2472 
2473 source "drivers/pcmcia/Kconfig"
2474 
2475 source "drivers/pci/hotplug/Kconfig"
2476 
2477 config RAPIDIO
2478         tristate "RapidIO support"
2479         depends on PCI
2480         default n
2481         help
2482           If enabled this option will include drivers and the core
2483           infrastructure code to support RapidIO interconnect devices.
2484 
2485 source "drivers/rapidio/Kconfig"
2486 
2487 config X86_SYSFB
2488         bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2489         help
2490           Firmwares often provide initial graphics framebuffers so the BIOS,
2491           bootloader or kernel can show basic video-output during boot for
2492           user-guidance and debugging. Historically, x86 used the VESA BIOS
2493           Extensions and EFI-framebuffers for this, which are mostly limited
2494           to x86.
2495           This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2496           framebuffers so the new generic system-framebuffer drivers can be
2497           used on x86. If the framebuffer is not compatible with the generic
2498           modes, it is adverticed as fallback platform framebuffer so legacy
2499           drivers like efifb, vesafb and uvesafb can pick it up.
2500           If this option is not selected, all system framebuffers are always
2501           marked as fallback platform framebuffers as usual.
2502 
2503           Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2504           not be able to pick up generic system framebuffers if this option
2505           is selected. You are highly encouraged to enable simplefb as
2506           replacement if you select this option. simplefb can correctly deal
2507           with generic system framebuffers. But you should still keep vesafb
2508           and others enabled as fallback if a system framebuffer is
2509           incompatible with simplefb.
2510 
2511           If unsure, say Y.
2512 
2513 endmenu
2514 
2515 
2516 menu "Executable file formats / Emulations"
2517 
2518 source "fs/Kconfig.binfmt"
2519 
2520 config IA32_EMULATION
2521         bool "IA32 Emulation"
2522         depends on X86_64
2523         select BINFMT_ELF
2524         select COMPAT_BINFMT_ELF
2525         select HAVE_UID16
2526         ---help---
2527           Include code to run legacy 32-bit programs under a
2528           64-bit kernel. You should likely turn this on, unless you're
2529           100% sure that you don't have any 32-bit programs left.
2530 
2531 config IA32_AOUT
2532         tristate "IA32 a.out support"
2533         depends on IA32_EMULATION
2534         ---help---
2535           Support old a.out binaries in the 32bit emulation.
2536 
2537 config X86_X32
2538         bool "x32 ABI for 64-bit mode"
2539         depends on X86_64 && IA32_EMULATION
2540         ---help---
2541           Include code to run binaries for the x32 native 32-bit ABI
2542           for 64-bit processors.  An x32 process gets access to the
2543           full 64-bit register file and wide data path while leaving
2544           pointers at 32 bits for smaller memory footprint.
2545 
2546           You will need a recent binutils (2.22 or later) with
2547           elf32_x86_64 support enabled to compile a kernel with this
2548           option set.
2549 
2550 config COMPAT
2551         def_bool y
2552         depends on IA32_EMULATION || X86_X32
2553         select ARCH_WANT_OLD_COMPAT_IPC
2554 
2555 if COMPAT
2556 config COMPAT_FOR_U64_ALIGNMENT
2557         def_bool y
2558 
2559 config SYSVIPC_COMPAT
2560         def_bool y
2561         depends on SYSVIPC
2562 
2563 config KEYS_COMPAT
2564         def_bool y
2565         depends on KEYS
2566 endif
2567 
2568 endmenu
2569 
2570 
2571 config HAVE_ATOMIC_IOMAP
2572         def_bool y
2573         depends on X86_32
2574 
2575 config X86_DEV_DMA_OPS
2576         bool
2577         depends on X86_64 || STA2X11
2578 
2579 config X86_DMA_REMAP
2580         bool
2581         depends on STA2X11
2582 
2583 config PMC_ATOM
2584         def_bool y
2585         depends on PCI
2586 
2587 source "net/Kconfig"
2588 
2589 source "drivers/Kconfig"
2590 
2591 source "drivers/firmware/Kconfig"
2592 
2593 source "fs/Kconfig"
2594 
2595 source "arch/x86/Kconfig.debug"
2596 
2597 source "security/Kconfig"
2598 
2599 source "crypto/Kconfig"
2600 
2601 source "arch/x86/kvm/Kconfig"
2602 
2603 source "lib/Kconfig"

This page was automatically generated by LXR 0.3.1 (source).  •  Linux is a registered trademark of Linus Torvalds  •  Contact us