| blob | 2dc18605831f6e88fd45c2863fc3d1fc7e6b6622 |
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
9 config X86_32
10 def_bool y
11 depends on !64BIT
13 config X86_64
14 def_bool y
15 depends on 64BIT
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_DEVMEM_IS_ALLOWED
28 select ARCH_HAS_ELF_RANDOMIZE
29 select ARCH_HAS_FAST_MULTIPLIER
30 select ARCH_HAS_GCOV_PROFILE_ALL
31 select ARCH_HAS_KCOV if X86_64
32 select ARCH_HAS_PMEM_API if X86_64
33 select ARCH_HAS_MMIO_FLUSH
34 select ARCH_HAS_SG_CHAIN
35 select ARCH_HAS_UBSAN_SANITIZE_ALL
36 select ARCH_HAVE_NMI_SAFE_CMPXCHG
37 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
38 select ARCH_MIGHT_HAVE_PC_PARPORT
39 select ARCH_MIGHT_HAVE_PC_SERIO
40 select ARCH_SUPPORTS_ATOMIC_RMW
41 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
42 select ARCH_SUPPORTS_INT128 if X86_64
43 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
44 select ARCH_USE_BUILTIN_BSWAP
45 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
46 select ARCH_USE_QUEUED_RWLOCKS
47 select ARCH_USE_QUEUED_SPINLOCKS
48 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
49 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
50 select ARCH_WANT_FRAME_POINTERS
51 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
52 select ARCH_WANT_OPTIONAL_GPIOLIB
53 select BUILDTIME_EXTABLE_SORT
54 select CLKEVT_I8253
55 select CLKSRC_I8253 if X86_32
56 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
57 select CLOCKSOURCE_WATCHDOG
58 select CLONE_BACKWARDS if X86_32
59 select COMPAT_OLD_SIGACTION if IA32_EMULATION
60 select DCACHE_WORD_ACCESS
61 select EDAC_ATOMIC_SCRUB
62 select EDAC_SUPPORT
63 select GENERIC_CLOCKEVENTS
64 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
65 select GENERIC_CLOCKEVENTS_MIN_ADJUST
66 select GENERIC_CMOS_UPDATE
67 select GENERIC_CPU_AUTOPROBE
68 select GENERIC_EARLY_IOREMAP
69 select GENERIC_FIND_FIRST_BIT
70 select GENERIC_IOMAP
71 select GENERIC_IRQ_PROBE
72 select GENERIC_IRQ_SHOW
73 select GENERIC_PENDING_IRQ if SMP
74 select GENERIC_SMP_IDLE_THREAD
75 select GENERIC_STRNCPY_FROM_USER
76 select GENERIC_STRNLEN_USER
77 select GENERIC_TIME_VSYSCALL
78 select HAVE_ACPI_APEI if ACPI
79 select HAVE_ACPI_APEI_NMI if ACPI
80 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
81 select HAVE_AOUT if X86_32
82 select HAVE_ARCH_AUDITSYSCALL
83 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
84 select HAVE_ARCH_JUMP_LABEL
85 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
86 select HAVE_ARCH_KGDB
87 select HAVE_ARCH_KMEMCHECK
88 select HAVE_ARCH_MMAP_RND_BITS if MMU
89 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
90 select HAVE_ARCH_SECCOMP_FILTER
91 select HAVE_ARCH_SOFT_DIRTY if X86_64
92 select HAVE_ARCH_TRACEHOOK
93 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
94 select HAVE_BPF_JIT if X86_64
95 select HAVE_CC_STACKPROTECTOR
96 select HAVE_CMPXCHG_DOUBLE
97 select HAVE_CMPXCHG_LOCAL
98 select HAVE_CONTEXT_TRACKING if X86_64
99 select HAVE_COPY_THREAD_TLS
100 select HAVE_C_RECORDMCOUNT
101 select HAVE_DEBUG_KMEMLEAK
102 select HAVE_DEBUG_STACKOVERFLOW
103 select HAVE_DMA_API_DEBUG
104 select HAVE_DMA_CONTIGUOUS
105 select HAVE_DYNAMIC_FTRACE
106 select HAVE_DYNAMIC_FTRACE_WITH_REGS
107 select HAVE_EFFICIENT_UNALIGNED_ACCESS
108 select HAVE_FENTRY if X86_64
109 select HAVE_FTRACE_MCOUNT_RECORD
110 select HAVE_FUNCTION_GRAPH_FP_TEST
111 select HAVE_FUNCTION_GRAPH_TRACER
112 select HAVE_FUNCTION_TRACER
113 select HAVE_GENERIC_DMA_COHERENT if X86_32
114 select HAVE_HW_BREAKPOINT
115 select HAVE_IDE
116 select HAVE_IOREMAP_PROT
117 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
118 select HAVE_IRQ_TIME_ACCOUNTING
119 select HAVE_KERNEL_BZIP2
120 select HAVE_KERNEL_GZIP
121 select HAVE_KERNEL_LZ4
122 select HAVE_KERNEL_LZMA
123 select HAVE_KERNEL_LZO
124 select HAVE_KERNEL_XZ
125 select HAVE_KPROBES
126 select HAVE_KPROBES_ON_FTRACE
127 select HAVE_KRETPROBES
128 select HAVE_KVM
129 select HAVE_LIVEPATCH if X86_64
130 select HAVE_MEMBLOCK
131 select HAVE_MEMBLOCK_NODE_MAP
132 select HAVE_MIXED_BREAKPOINTS_REGS
133 select HAVE_OPROFILE
134 select HAVE_OPTPROBES
135 select HAVE_PCSPKR_PLATFORM
136 select HAVE_PERF_EVENTS
137 select HAVE_PERF_EVENTS_NMI
138 select HAVE_PERF_REGS
139 select HAVE_PERF_USER_STACK_DUMP
140 select HAVE_REGS_AND_STACK_ACCESS_API
141 select HAVE_SYSCALL_TRACEPOINTS
142 select HAVE_UID16 if X86_32 || IA32_EMULATION
143 select HAVE_UNSTABLE_SCHED_CLOCK
144 select HAVE_USER_RETURN_NOTIFIER
145 select IRQ_FORCED_THREADING
146 select MODULES_USE_ELF_RELA if X86_64
147 select MODULES_USE_ELF_REL if X86_32
148 select OLD_SIGACTION if X86_32
149 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
150 select PERF_EVENTS
151 select RTC_LIB
152 select SPARSE_IRQ
153 select SRCU
154 select SYSCTL_EXCEPTION_TRACE
155 select USER_STACKTRACE_SUPPORT
156 select VIRT_TO_BUS
157 select X86_DEV_DMA_OPS if X86_64
158 select X86_FEATURE_NAMES if PROC_FS
159 select HAVE_STACK_VALIDATION if X86_64
160 select ARCH_USES_HIGH_VMA_FLAGS if X86_INTEL_MEMORY_PROTECTION_KEYS
161 select ARCH_HAS_PKEYS if X86_INTEL_MEMORY_PROTECTION_KEYS
163 config INSTRUCTION_DECODER
164 def_bool y
165 depends on KPROBES || PERF_EVENTS || UPROBES
167 config PERF_EVENTS_INTEL_UNCORE
168 def_bool y
169 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
171 config OUTPUT_FORMAT
172 string
173 default "elf32-i386" if X86_32
174 default "elf64-x86-64" if X86_64
176 config ARCH_DEFCONFIG
177 string
178 default "arch/x86/configs/i386_defconfig" if X86_32
179 default "arch/x86/configs/x86_64_defconfig" if X86_64
181 config LOCKDEP_SUPPORT
182 def_bool y
184 config STACKTRACE_SUPPORT
185 def_bool y
187 config MMU
188 def_bool y
190 config ARCH_MMAP_RND_BITS_MIN
191 default 28 if 64BIT
192 default 8
194 config ARCH_MMAP_RND_BITS_MAX
195 default 32 if 64BIT
196 default 16
198 config ARCH_MMAP_RND_COMPAT_BITS_MIN
199 default 8
201 config ARCH_MMAP_RND_COMPAT_BITS_MAX
202 default 16
204 config SBUS
205 bool
207 config NEED_DMA_MAP_STATE
208 def_bool y
209 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
211 config NEED_SG_DMA_LENGTH
212 def_bool y
214 config GENERIC_ISA_DMA
215 def_bool y
216 depends on ISA_DMA_API
218 config GENERIC_BUG
219 def_bool y
220 depends on BUG
221 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
223 config GENERIC_BUG_RELATIVE_POINTERS
224 bool
226 config GENERIC_HWEIGHT
227 def_bool y
229 config ARCH_MAY_HAVE_PC_FDC
230 def_bool y
231 depends on ISA_DMA_API
233 config RWSEM_XCHGADD_ALGORITHM
234 def_bool y
236 config GENERIC_CALIBRATE_DELAY
237 def_bool y
239 config ARCH_HAS_CPU_RELAX
240 def_bool y
242 config ARCH_HAS_CACHE_LINE_SIZE
243 def_bool y
245 config HAVE_SETUP_PER_CPU_AREA
246 def_bool y
248 config NEED_PER_CPU_EMBED_FIRST_CHUNK
249 def_bool y
251 config NEED_PER_CPU_PAGE_FIRST_CHUNK
252 def_bool y
254 config ARCH_HIBERNATION_POSSIBLE
255 def_bool y
257 config ARCH_SUSPEND_POSSIBLE
258 def_bool y
260 config ARCH_WANT_HUGE_PMD_SHARE
261 def_bool y
263 config ARCH_WANT_GENERAL_HUGETLB
264 def_bool y
266 config ZONE_DMA32
267 def_bool y if X86_64
269 config AUDIT_ARCH
270 def_bool y if X86_64
272 config ARCH_SUPPORTS_OPTIMIZED_INLINING
273 def_bool y
275 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
276 def_bool y
278 config KASAN_SHADOW_OFFSET
279 hex
280 depends on KASAN
281 default 0xdffffc0000000000
283 config HAVE_INTEL_TXT
284 def_bool y
285 depends on INTEL_IOMMU && ACPI
287 config X86_32_SMP
288 def_bool y
289 depends on X86_32 && SMP
291 config X86_64_SMP
292 def_bool y
293 depends on X86_64 && SMP
295 config X86_32_LAZY_GS
296 def_bool y
297 depends on X86_32 && !CC_STACKPROTECTOR
299 config ARCH_HWEIGHT_CFLAGS
300 string
301 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
302 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
304 config ARCH_SUPPORTS_UPROBES
305 def_bool y
307 config FIX_EARLYCON_MEM
308 def_bool y
310 config DEBUG_RODATA
311 def_bool y
313 config PGTABLE_LEVELS
314 int
315 default 4 if X86_64
316 default 3 if X86_PAE
317 default 2
319 source "init/Kconfig"
320 source "kernel/Kconfig.freezer"
322 menu "Processor type and features"
324 config ZONE_DMA
325 bool "DMA memory allocation support" if EXPERT
326 default y
327 help
328 DMA memory allocation support allows devices with less than 32-bit
329 addressing to allocate within the first 16MB of address space.
330 Disable if no such devices will be used.
332 If unsure, say Y.
334 config SMP
335 bool "Symmetric multi-processing support"
336 ---help---
337 This enables support for systems with more than one CPU. If you have
338 a system with only one CPU, say N. If you have a system with more
339 than one CPU, say Y.
341 If you say N here, the kernel will run on uni- and multiprocessor
342 machines, but will use only one CPU of a multiprocessor machine. If
343 you say Y here, the kernel will run on many, but not all,
344 uniprocessor machines. On a uniprocessor machine, the kernel
345 will run faster if you say N here.
347 Note that if you say Y here and choose architecture "586" or
348 "Pentium" under "Processor family", the kernel will not work on 486
349 architectures. Similarly, multiprocessor kernels for the "PPro"
350 architecture may not work on all Pentium based boards.
352 People using multiprocessor machines who say Y here should also say
353 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
354 Management" code will be disabled if you say Y here.
356 See also <file:Documentation/x86/i386/IO-APIC.txt>,
357 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
358 <http://www.tldp.org/docs.html#howto>.
360 If you don't know what to do here, say N.
362 config X86_FEATURE_NAMES
363 bool "Processor feature human-readable names" if EMBEDDED
364 default y
365 ---help---
366 This option compiles in a table of x86 feature bits and corresponding
367 names. This is required to support /proc/cpuinfo and a few kernel
368 messages. You can disable this to save space, at the expense of
369 making those few kernel messages show numeric feature bits instead.
371 If in doubt, say Y.
373 config X86_FAST_FEATURE_TESTS
374 bool "Fast CPU feature tests" if EMBEDDED
375 default y
376 ---help---
377 Some fast-paths in the kernel depend on the capabilities of the CPU.
378 Say Y here for the kernel to patch in the appropriate code at runtime
379 based on the capabilities of the CPU. The infrastructure for patching
380 code at runtime takes up some additional space; space-constrained
381 embedded systems may wish to say N here to produce smaller, slightly
382 slower code.
384 config X86_X2APIC
385 bool "Support x2apic"
386 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
387 ---help---
388 This enables x2apic support on CPUs that have this feature.
390 This allows 32-bit apic IDs (so it can support very large systems),
391 and accesses the local apic via MSRs not via mmio.
393 If you don't know what to do here, say N.
395 config X86_MPPARSE
396 bool "Enable MPS table" if ACPI || SFI
397 default y
398 depends on X86_LOCAL_APIC
399 ---help---
400 For old smp systems that do not have proper acpi support. Newer systems
401 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
403 config X86_BIGSMP
404 bool "Support for big SMP systems with more than 8 CPUs"
405 depends on X86_32 && SMP
406 ---help---
407 This option is needed for the systems that have more than 8 CPUs
409 config GOLDFISH
410 def_bool y
411 depends on X86_GOLDFISH
413 if X86_32
414 config X86_EXTENDED_PLATFORM
415 bool "Support for extended (non-PC) x86 platforms"
416 default y
417 ---help---
418 If you disable this option then the kernel will only support
419 standard PC platforms. (which covers the vast majority of
420 systems out there.)
422 If you enable this option then you'll be able to select support
423 for the following (non-PC) 32 bit x86 platforms:
424 Goldfish (Android emulator)
425 AMD Elan
426 RDC R-321x SoC
427 SGI 320/540 (Visual Workstation)
428 STA2X11-based (e.g. Northville)
429 Moorestown MID devices
431 If you have one of these systems, or if you want to build a
432 generic distribution kernel, say Y here - otherwise say N.
433 endif
435 if X86_64
436 config X86_EXTENDED_PLATFORM
437 bool "Support for extended (non-PC) x86 platforms"
438 default y
439 ---help---
440 If you disable this option then the kernel will only support
441 standard PC platforms. (which covers the vast majority of
442 systems out there.)
444 If you enable this option then you'll be able to select support
445 for the following (non-PC) 64 bit x86 platforms:
446 Numascale NumaChip
447 ScaleMP vSMP
448 SGI Ultraviolet
450 If you have one of these systems, or if you want to build a
451 generic distribution kernel, say Y here - otherwise say N.
452 endif
453 # This is an alphabetically sorted list of 64 bit extended platforms
454 # Please maintain the alphabetic order if and when there are additions
455 config X86_NUMACHIP
456 bool "Numascale NumaChip"
457 depends on X86_64
458 depends on X86_EXTENDED_PLATFORM
459 depends on NUMA
460 depends on SMP
461 depends on X86_X2APIC
462 depends on PCI_MMCONFIG
463 ---help---
464 Adds support for Numascale NumaChip large-SMP systems. Needed to
465 enable more than ~168 cores.
466 If you don't have one of these, you should say N here.
468 config X86_VSMP
469 bool "ScaleMP vSMP"
470 select HYPERVISOR_GUEST
471 select PARAVIRT
472 depends on X86_64 && PCI
473 depends on X86_EXTENDED_PLATFORM
474 depends on SMP
475 ---help---
476 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
477 supposed to run on these EM64T-based machines. Only choose this option
478 if you have one of these machines.
480 config X86_UV
481 bool "SGI Ultraviolet"
482 depends on X86_64
483 depends on X86_EXTENDED_PLATFORM
484 depends on NUMA
485 depends on EFI
486 depends on X86_X2APIC
487 depends on PCI
488 ---help---
489 This option is needed in order to support SGI Ultraviolet systems.
490 If you don't have one of these, you should say N here.
492 # Following is an alphabetically sorted list of 32 bit extended platforms
493 # Please maintain the alphabetic order if and when there are additions
495 config X86_GOLDFISH
496 bool "Goldfish (Virtual Platform)"
497 depends on X86_EXTENDED_PLATFORM
498 ---help---
499 Enable support for the Goldfish virtual platform used primarily
500 for Android development. Unless you are building for the Android
501 Goldfish emulator say N here.
503 config X86_INTEL_CE
504 bool "CE4100 TV platform"
505 depends on PCI
506 depends on PCI_GODIRECT
507 depends on X86_IO_APIC
508 depends on X86_32
509 depends on X86_EXTENDED_PLATFORM
510 select X86_REBOOTFIXUPS
511 select OF
512 select OF_EARLY_FLATTREE
513 ---help---
514 Select for the Intel CE media processor (CE4100) SOC.
515 This option compiles in support for the CE4100 SOC for settop
516 boxes and media devices.
518 config X86_INTEL_MID
519 bool "Intel MID platform support"
520 depends on X86_EXTENDED_PLATFORM
521 depends on X86_PLATFORM_DEVICES
522 depends on PCI
523 depends on X86_64 || (PCI_GOANY && X86_32)
524 depends on X86_IO_APIC
525 select SFI
526 select I2C
527 select DW_APB_TIMER
528 select APB_TIMER
529 select INTEL_SCU_IPC
530 select MFD_INTEL_MSIC
531 ---help---
532 Select to build a kernel capable of supporting Intel MID (Mobile
533 Internet Device) platform systems which do not have the PCI legacy
534 interfaces. If you are building for a PC class system say N here.
536 Intel MID platforms are based on an Intel processor and chipset which
537 consume less power than most of the x86 derivatives.
539 config X86_INTEL_QUARK
540 bool "Intel Quark platform support"
541 depends on X86_32
542 depends on X86_EXTENDED_PLATFORM
543 depends on X86_PLATFORM_DEVICES
544 depends on X86_TSC
545 depends on PCI
546 depends on PCI_GOANY
547 depends on X86_IO_APIC
548 select IOSF_MBI
549 select INTEL_IMR
550 select COMMON_CLK
551 ---help---
552 Select to include support for Quark X1000 SoC.
553 Say Y here if you have a Quark based system such as the Arduino
554 compatible Intel Galileo.
556 config X86_INTEL_LPSS
557 bool "Intel Low Power Subsystem Support"
558 depends on X86 && ACPI
559 select COMMON_CLK
560 select PINCTRL
561 select IOSF_MBI
562 ---help---
563 Select to build support for Intel Low Power Subsystem such as
564 found on Intel Lynxpoint PCH. Selecting this option enables
565 things like clock tree (common clock framework) and pincontrol
566 which are needed by the LPSS peripheral drivers.
568 config X86_AMD_PLATFORM_DEVICE
569 bool "AMD ACPI2Platform devices support"
570 depends on ACPI
571 select COMMON_CLK
572 select PINCTRL
573 ---help---
574 Select to interpret AMD specific ACPI device to platform device
575 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
576 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
577 implemented under PINCTRL subsystem.
579 config IOSF_MBI
580 tristate "Intel SoC IOSF Sideband support for SoC platforms"
581 depends on PCI
582 ---help---
583 This option enables sideband register access support for Intel SoC
584 platforms. On these platforms the IOSF sideband is used in lieu of
585 MSR's for some register accesses, mostly but not limited to thermal
586 and power. Drivers may query the availability of this device to
587 determine if they need the sideband in order to work on these
588 platforms. The sideband is available on the following SoC products.
589 This list is not meant to be exclusive.
590 - BayTrail
591 - Braswell
592 - Quark
594 You should say Y if you are running a kernel on one of these SoC's.
596 config IOSF_MBI_DEBUG
597 bool "Enable IOSF sideband access through debugfs"
598 depends on IOSF_MBI && DEBUG_FS
599 ---help---
600 Select this option to expose the IOSF sideband access registers (MCR,
601 MDR, MCRX) through debugfs to write and read register information from
602 different units on the SoC. This is most useful for obtaining device
603 state information for debug and analysis. As this is a general access
604 mechanism, users of this option would have specific knowledge of the
605 device they want to access.
607 If you don't require the option or are in doubt, say N.
609 config X86_RDC321X
610 bool "RDC R-321x SoC"
611 depends on X86_32
612 depends on X86_EXTENDED_PLATFORM
613 select M486
614 select X86_REBOOTFIXUPS
615 ---help---
616 This option is needed for RDC R-321x system-on-chip, also known
617 as R-8610-(G).
618 If you don't have one of these chips, you should say N here.
620 config X86_32_NON_STANDARD
621 bool "Support non-standard 32-bit SMP architectures"
622 depends on X86_32 && SMP
623 depends on X86_EXTENDED_PLATFORM
624 ---help---
625 This option compiles in the bigsmp and STA2X11 default
626 subarchitectures. It is intended for a generic binary
627 kernel. If you select them all, kernel will probe it one by
628 one and will fallback to default.
630 # Alphabetically sorted list of Non standard 32 bit platforms
632 config X86_SUPPORTS_MEMORY_FAILURE
633 def_bool y
634 # MCE code calls memory_failure():
635 depends on X86_MCE
636 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
637 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
638 depends on X86_64 || !SPARSEMEM
639 select ARCH_SUPPORTS_MEMORY_FAILURE
641 config STA2X11
642 bool "STA2X11 Companion Chip Support"
643 depends on X86_32_NON_STANDARD && PCI
644 select X86_DEV_DMA_OPS
645 select X86_DMA_REMAP
646 select SWIOTLB
647 select MFD_STA2X11
648 select ARCH_REQUIRE_GPIOLIB
649 default n
650 ---help---
651 This adds support for boards based on the STA2X11 IO-Hub,
652 a.k.a. "ConneXt". The chip is used in place of the standard
653 PC chipset, so all "standard" peripherals are missing. If this
654 option is selected the kernel will still be able to boot on
655 standard PC machines.
657 config X86_32_IRIS
658 tristate "Eurobraille/Iris poweroff module"
659 depends on X86_32
660 ---help---
661 The Iris machines from EuroBraille do not have APM or ACPI support
662 to shut themselves down properly. A special I/O sequence is
663 needed to do so, which is what this module does at
664 kernel shutdown.
666 This is only for Iris machines from EuroBraille.
668 If unused, say N.
670 config SCHED_OMIT_FRAME_POINTER
671 def_bool y
672 prompt "Single-depth WCHAN output"
673 depends on X86
674 ---help---
675 Calculate simpler /proc/<PID>/wchan values. If this option
676 is disabled then wchan values will recurse back to the
677 caller function. This provides more accurate wchan values,
678 at the expense of slightly more scheduling overhead.
680 If in doubt, say "Y".
682 menuconfig HYPERVISOR_GUEST
683 bool "Linux guest support"
684 ---help---
685 Say Y here to enable options for running Linux under various hyper-
686 visors. This option enables basic hypervisor detection and platform
687 setup.
689 If you say N, all options in this submenu will be skipped and
690 disabled, and Linux guest support won't be built in.
692 if HYPERVISOR_GUEST
694 config PARAVIRT
695 bool "Enable paravirtualization code"
696 ---help---
697 This changes the kernel so it can modify itself when it is run
698 under a hypervisor, potentially improving performance significantly
699 over full virtualization. However, when run without a hypervisor
700 the kernel is theoretically slower and slightly larger.
702 config PARAVIRT_DEBUG
703 bool "paravirt-ops debugging"
704 depends on PARAVIRT && DEBUG_KERNEL
705 ---help---
706 Enable to debug paravirt_ops internals. Specifically, BUG if
707 a paravirt_op is missing when it is called.
709 config PARAVIRT_SPINLOCKS
710 bool "Paravirtualization layer for spinlocks"
711 depends on PARAVIRT && SMP
712 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
713 ---help---
714 Paravirtualized spinlocks allow a pvops backend to replace the
715 spinlock implementation with something virtualization-friendly
716 (for example, block the virtual CPU rather than spinning).
718 It has a minimal impact on native kernels and gives a nice performance
719 benefit on paravirtualized KVM / Xen kernels.
721 If you are unsure how to answer this question, answer Y.
723 config QUEUED_LOCK_STAT
724 bool "Paravirt queued spinlock statistics"
725 depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS
726 ---help---
727 Enable the collection of statistical data on the slowpath
728 behavior of paravirtualized queued spinlocks and report
729 them on debugfs.
731 source "arch/x86/xen/Kconfig"
733 config KVM_GUEST
734 bool "KVM Guest support (including kvmclock)"
735 depends on PARAVIRT
736 select PARAVIRT_CLOCK
737 default y
738 ---help---
739 This option enables various optimizations for running under the KVM
740 hypervisor. It includes a paravirtualized clock, so that instead
741 of relying on a PIT (or probably other) emulation by the
742 underlying device model, the host provides the guest with
743 timing infrastructure such as time of day, and system time
745 config KVM_DEBUG_FS
746 bool "Enable debug information for KVM Guests in debugfs"
747 depends on KVM_GUEST && DEBUG_FS
748 default n
749 ---help---
750 This option enables collection of various statistics for KVM guest.
751 Statistics are displayed in debugfs filesystem. Enabling this option
752 may incur significant overhead.
754 source "arch/x86/lguest/Kconfig"
756 config PARAVIRT_TIME_ACCOUNTING
757 bool "Paravirtual steal time accounting"
758 depends on PARAVIRT
759 default n
760 ---help---
761 Select this option to enable fine granularity task steal time
762 accounting. Time spent executing other tasks in parallel with
763 the current vCPU is discounted from the vCPU power. To account for
764 that, there can be a small performance impact.
766 If in doubt, say N here.
768 config PARAVIRT_CLOCK
769 bool
771 endif #HYPERVISOR_GUEST
773 config NO_BOOTMEM
774 def_bool y
776 source "arch/x86/Kconfig.cpu"
778 config HPET_TIMER
779 def_bool X86_64
780 prompt "HPET Timer Support" if X86_32
781 ---help---
782 Use the IA-PC HPET (High Precision Event Timer) to manage
783 time in preference to the PIT and RTC, if a HPET is
784 present.
785 HPET is the next generation timer replacing legacy 8254s.
786 The HPET provides a stable time base on SMP
787 systems, unlike the TSC, but it is more expensive to access,
788 as it is off-chip. The interface used is documented
789 in the HPET spec, revision 1.
791 You can safely choose Y here. However, HPET will only be
792 activated if the platform and the BIOS support this feature.
793 Otherwise the 8254 will be used for timing services.
795 Choose N to continue using the legacy 8254 timer.
797 config HPET_EMULATE_RTC
798 def_bool y
799 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
801 config APB_TIMER
802 def_bool y if X86_INTEL_MID
803 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
804 select DW_APB_TIMER
805 depends on X86_INTEL_MID && SFI
806 help
807 APB timer is the replacement for 8254, HPET on X86 MID platforms.
808 The APBT provides a stable time base on SMP
809 systems, unlike the TSC, but it is more expensive to access,
810 as it is off-chip. APB timers are always running regardless of CPU
811 C states, they are used as per CPU clockevent device when possible.
813 # Mark as expert because too many people got it wrong.
814 # The code disables itself when not needed.
815 config DMI
816 default y
817 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
818 bool "Enable DMI scanning" if EXPERT
819 ---help---
820 Enabled scanning of DMI to identify machine quirks. Say Y
821 here unless you have verified that your setup is not
822 affected by entries in the DMI blacklist. Required by PNP
823 BIOS code.
825 config GART_IOMMU
826 bool "Old AMD GART IOMMU support"
827 select SWIOTLB
828 depends on X86_64 && PCI && AMD_NB
829 ---help---
830 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
831 GART based hardware IOMMUs.
833 The GART supports full DMA access for devices with 32-bit access
834 limitations, on systems with more than 3 GB. This is usually needed
835 for USB, sound, many IDE/SATA chipsets and some other devices.
837 Newer systems typically have a modern AMD IOMMU, supported via
838 the CONFIG_AMD_IOMMU=y config option.
840 In normal configurations this driver is only active when needed:
841 there's more than 3 GB of memory and the system contains a
842 32-bit limited device.
844 If unsure, say Y.
846 config CALGARY_IOMMU
847 bool "IBM Calgary IOMMU support"
848 select SWIOTLB
849 depends on X86_64 && PCI
850 ---help---
851 Support for hardware IOMMUs in IBM's xSeries x366 and x460
852 systems. Needed to run systems with more than 3GB of memory
853 properly with 32-bit PCI devices that do not support DAC
854 (Double Address Cycle). Calgary also supports bus level
855 isolation, where all DMAs pass through the IOMMU. This
856 prevents them from going anywhere except their intended
857 destination. This catches hard-to-find kernel bugs and
858 mis-behaving drivers and devices that do not use the DMA-API
859 properly to set up their DMA buffers. The IOMMU can be
860 turned off at boot time with the iommu=off parameter.
861 Normally the kernel will make the right choice by itself.
862 If unsure, say Y.
864 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
865 def_bool y
866 prompt "Should Calgary be enabled by default?"
867 depends on CALGARY_IOMMU
868 ---help---
869 Should Calgary be enabled by default? if you choose 'y', Calgary
870 will be used (if it exists). If you choose 'n', Calgary will not be
871 used even if it exists. If you choose 'n' and would like to use
872 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
873 If unsure, say Y.
875 # need this always selected by IOMMU for the VIA workaround
876 config SWIOTLB
877 def_bool y if X86_64
878 ---help---
879 Support for software bounce buffers used on x86-64 systems
880 which don't have a hardware IOMMU. Using this PCI devices
881 which can only access 32-bits of memory can be used on systems
882 with more than 3 GB of memory.
883 If unsure, say Y.
885 config IOMMU_HELPER
886 def_bool y
887 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
889 config MAXSMP
890 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
891 depends on X86_64 && SMP && DEBUG_KERNEL
892 select CPUMASK_OFFSTACK
893 ---help---
894 Enable maximum number of CPUS and NUMA Nodes for this architecture.
895 If unsure, say N.
897 config NR_CPUS
898 int "Maximum number of CPUs" if SMP && !MAXSMP
899 range 2 8 if SMP && X86_32 && !X86_BIGSMP
900 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
901 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
902 default "1" if !SMP
903 default "8192" if MAXSMP
904 default "32" if SMP && X86_BIGSMP
905 default "8" if SMP && X86_32
906 default "64" if SMP
907 ---help---
908 This allows you to specify the maximum number of CPUs which this
909 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
910 supported value is 8192, otherwise the maximum value is 512. The
911 minimum value which makes sense is 2.
913 This is purely to save memory - each supported CPU adds
914 approximately eight kilobytes to the kernel image.
916 config SCHED_SMT
917 bool "SMT (Hyperthreading) scheduler support"
918 depends on SMP
919 ---help---
920 SMT scheduler support improves the CPU scheduler's decision making
921 when dealing with Intel Pentium 4 chips with HyperThreading at a
922 cost of slightly increased overhead in some places. If unsure say
923 N here.
925 config SCHED_MC
926 def_bool y
927 prompt "Multi-core scheduler support"
928 depends on SMP
929 ---help---
930 Multi-core scheduler support improves the CPU scheduler's decision
931 making when dealing with multi-core CPU chips at a cost of slightly
932 increased overhead in some places. If unsure say N here.
934 source "kernel/Kconfig.preempt"
936 config UP_LATE_INIT
937 def_bool y
938 depends on !SMP && X86_LOCAL_APIC
940 config X86_UP_APIC
941 bool "Local APIC support on uniprocessors" if !PCI_MSI
942 default PCI_MSI
943 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
944 ---help---
945 A local APIC (Advanced Programmable Interrupt Controller) is an
946 integrated interrupt controller in the CPU. If you have a single-CPU
947 system which has a processor with a local APIC, you can say Y here to
948 enable and use it. If you say Y here even though your machine doesn't
949 have a local APIC, then the kernel will still run with no slowdown at
950 all. The local APIC supports CPU-generated self-interrupts (timer,
951 performance counters), and the NMI watchdog which detects hard
952 lockups.
954 config X86_UP_IOAPIC
955 bool "IO-APIC support on uniprocessors"
956 depends on X86_UP_APIC
957 ---help---
958 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
959 SMP-capable replacement for PC-style interrupt controllers. Most
960 SMP systems and many recent uniprocessor systems have one.
962 If you have a single-CPU system with an IO-APIC, you can say Y here
963 to use it. If you say Y here even though your machine doesn't have
964 an IO-APIC, then the kernel will still run with no slowdown at all.
966 config X86_LOCAL_APIC
967 def_bool y
968 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
969 select IRQ_DOMAIN_HIERARCHY
970 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
972 config X86_IO_APIC
973 def_bool y
974 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
976 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
977 bool "Reroute for broken boot IRQs"
978 depends on X86_IO_APIC
979 ---help---
980 This option enables a workaround that fixes a source of
981 spurious interrupts. This is recommended when threaded
982 interrupt handling is used on systems where the generation of
983 superfluous "boot interrupts" cannot be disabled.
985 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
986 entry in the chipset's IO-APIC is masked (as, e.g. the RT
987 kernel does during interrupt handling). On chipsets where this
988 boot IRQ generation cannot be disabled, this workaround keeps
989 the original IRQ line masked so that only the equivalent "boot
990 IRQ" is delivered to the CPUs. The workaround also tells the
991 kernel to set up the IRQ handler on the boot IRQ line. In this
992 way only one interrupt is delivered to the kernel. Otherwise
993 the spurious second interrupt may cause the kernel to bring
994 down (vital) interrupt lines.
996 Only affects "broken" chipsets. Interrupt sharing may be
997 increased on these systems.
999 config X86_MCE
1000 bool "Machine Check / overheating reporting"
1001 select GENERIC_ALLOCATOR
1002 default y
1003 ---help---
1004 Machine Check support allows the processor to notify the
1005 kernel if it detects a problem (e.g. overheating, data corruption).
1006 The action the kernel takes depends on the severity of the problem,
1007 ranging from warning messages to halting the machine.
1009 config X86_MCE_INTEL
1010 def_bool y
1011 prompt "Intel MCE features"
1012 depends on X86_MCE && X86_LOCAL_APIC
1013 ---help---
1014 Additional support for intel specific MCE features such as
1015 the thermal monitor.
1017 config X86_MCE_AMD
1018 def_bool y
1019 prompt "AMD MCE features"
1020 depends on X86_MCE && X86_LOCAL_APIC
1021 ---help---
1022 Additional support for AMD specific MCE features such as
1023 the DRAM Error Threshold.
1025 config X86_ANCIENT_MCE
1026 bool "Support for old Pentium 5 / WinChip machine checks"
1027 depends on X86_32 && X86_MCE
1028 ---help---
1029 Include support for machine check handling on old Pentium 5 or WinChip
1030 systems. These typically need to be enabled explicitly on the command
1031 line.
1033 config X86_MCE_THRESHOLD
1034 depends on X86_MCE_AMD || X86_MCE_INTEL
1035 def_bool y
1037 config X86_MCE_INJECT
1038 depends on X86_MCE
1039 tristate "Machine check injector support"
1040 ---help---
1041 Provide support for injecting machine checks for testing purposes.
1042 If you don't know what a machine check is and you don't do kernel
1043 QA it is safe to say n.
1045 config X86_THERMAL_VECTOR
1046 def_bool y
1047 depends on X86_MCE_INTEL
1049 config X86_LEGACY_VM86
1050 bool "Legacy VM86 support"
1051 default n
1052 depends on X86_32
1053 ---help---
1054 This option allows user programs to put the CPU into V8086
1055 mode, which is an 80286-era approximation of 16-bit real mode.
1057 Some very old versions of X and/or vbetool require this option
1058 for user mode setting. Similarly, DOSEMU will use it if
1059 available to accelerate real mode DOS programs. However, any
1060 recent version of DOSEMU, X, or vbetool should be fully
1061 functional even without kernel VM86 support, as they will all
1062 fall back to software emulation. Nevertheless, if you are using
1063 a 16-bit DOS program where 16-bit performance matters, vm86
1064 mode might be faster than emulation and you might want to
1065 enable this option.
1067 Note that any app that works on a 64-bit kernel is unlikely to
1068 need this option, as 64-bit kernels don't, and can't, support
1069 V8086 mode. This option is also unrelated to 16-bit protected
1070 mode and is not needed to run most 16-bit programs under Wine.
1072 Enabling this option increases the complexity of the kernel
1073 and slows down exception handling a tiny bit.
1075 If unsure, say N here.
1077 config VM86
1078 bool
1079 default X86_LEGACY_VM86
1081 config X86_16BIT
1082 bool "Enable support for 16-bit segments" if EXPERT
1083 default y
1084 depends on MODIFY_LDT_SYSCALL
1085 ---help---
1086 This option is required by programs like Wine to run 16-bit
1087 protected mode legacy code on x86 processors. Disabling
1088 this option saves about 300 bytes on i386, or around 6K text
1089 plus 16K runtime memory on x86-64,
1091 config X86_ESPFIX32
1092 def_bool y
1093 depends on X86_16BIT && X86_32
1095 config X86_ESPFIX64
1096 def_bool y
1097 depends on X86_16BIT && X86_64
1099 config X86_VSYSCALL_EMULATION
1100 bool "Enable vsyscall emulation" if EXPERT
1101 default y
1102 depends on X86_64
1103 ---help---
1104 This enables emulation of the legacy vsyscall page. Disabling
1105 it is roughly equivalent to booting with vsyscall=none, except
1106 that it will also disable the helpful warning if a program
1107 tries to use a vsyscall. With this option set to N, offending
1108 programs will just segfault, citing addresses of the form
1109 0xffffffffff600?00.
1111 This option is required by many programs built before 2013, and
1112 care should be used even with newer programs if set to N.
1114 Disabling this option saves about 7K of kernel size and
1115 possibly 4K of additional runtime pagetable memory.
1117 config TOSHIBA
1118 tristate "Toshiba Laptop support"
1119 depends on X86_32
1120 ---help---
1121 This adds a driver to safely access the System Management Mode of
1122 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1123 not work on models with a Phoenix BIOS. The System Management Mode
1124 is used to set the BIOS and power saving options on Toshiba portables.
1126 For information on utilities to make use of this driver see the
1127 Toshiba Linux utilities web site at:
1128 <http://www.buzzard.org.uk/toshiba/>.
1130 Say Y if you intend to run this kernel on a Toshiba portable.
1131 Say N otherwise.
1133 config I8K
1134 tristate "Dell i8k legacy laptop support"
1135 select HWMON
1136 select SENSORS_DELL_SMM
1137 ---help---
1138 This option enables legacy /proc/i8k userspace interface in hwmon
1139 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1140 temperature and allows controlling fan speeds of Dell laptops via
1141 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1142 it reports also power and hotkey status. For fan speed control is
1143 needed userspace package i8kutils.
1145 Say Y if you intend to run this kernel on old Dell laptops or want to
1146 use userspace package i8kutils.
1147 Say N otherwise.
1149 config X86_REBOOTFIXUPS
1150 bool "Enable X86 board specific fixups for reboot"
1151 depends on X86_32
1152 ---help---
1153 This enables chipset and/or board specific fixups to be done
1154 in order to get reboot to work correctly. This is only needed on
1155 some combinations of hardware and BIOS. The symptom, for which
1156 this config is intended, is when reboot ends with a stalled/hung
1157 system.
1159 Currently, the only fixup is for the Geode machines using
1160 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1162 Say Y if you want to enable the fixup. Currently, it's safe to
1163 enable this option even if you don't need it.
1164 Say N otherwise.
1166 config MICROCODE
1167 bool "CPU microcode loading support"
1168 default y
1169 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1170 select FW_LOADER
1171 ---help---
1172 If you say Y here, you will be able to update the microcode on
1173 Intel and AMD processors. The Intel support is for the IA32 family,
1174 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1175 AMD support is for families 0x10 and later. You will obviously need
1176 the actual microcode binary data itself which is not shipped with
1177 the Linux kernel.
1179 The preferred method to load microcode from a detached initrd is described
1180 in Documentation/x86/early-microcode.txt. For that you need to enable
1181 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1182 initrd for microcode blobs.
1184 In addition, you can build-in the microcode into the kernel. For that you
1185 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
1186 to the CONFIG_EXTRA_FIRMWARE config option.
1188 config MICROCODE_INTEL
1189 bool "Intel microcode loading support"
1190 depends on MICROCODE
1191 default MICROCODE
1192 select FW_LOADER
1193 ---help---
1194 This options enables microcode patch loading support for Intel
1195 processors.
1197 For the current Intel microcode data package go to
1198 <https://downloadcenter.intel.com> and search for
1199 'Linux Processor Microcode Data File'.
1201 config MICROCODE_AMD
1202 bool "AMD microcode loading support"
1203 depends on MICROCODE
1204 select FW_LOADER
1205 ---help---
1206 If you select this option, microcode patch loading support for AMD
1207 processors will be enabled.
1209 config MICROCODE_OLD_INTERFACE
1210 def_bool y
1211 depends on MICROCODE
1213 config PERF_EVENTS_AMD_POWER
1214 depends on PERF_EVENTS && CPU_SUP_AMD
1215 tristate "AMD Processor Power Reporting Mechanism"
1216 ---help---
1217 Provide power reporting mechanism support for AMD processors.
1218 Currently, it leverages X86_FEATURE_ACC_POWER
1219 (CPUID Fn8000_0007_EDX[12]) interface to calculate the
1220 average power consumption on Family 15h processors.
1222 config X86_MSR
1223 tristate "/dev/cpu/*/msr - Model-specific register support"
1224 ---help---
1225 This device gives privileged processes access to the x86
1226 Model-Specific Registers (MSRs). It is a character device with
1227 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1228 MSR accesses are directed to a specific CPU on multi-processor
1229 systems.
1231 config X86_CPUID
1232 tristate "/dev/cpu/*/cpuid - CPU information support"
1233 ---help---
1234 This device gives processes access to the x86 CPUID instruction to
1235 be executed on a specific processor. It is a character device
1236 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1237 /dev/cpu/31/cpuid.
1239 choice
1240 prompt "High Memory Support"
1241 default HIGHMEM4G
1242 depends on X86_32
1244 config NOHIGHMEM
1245 bool "off"
1246 ---help---
1247 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1248 However, the address space of 32-bit x86 processors is only 4
1249 Gigabytes large. That means that, if you have a large amount of
1250 physical memory, not all of it can be "permanently mapped" by the
1251 kernel. The physical memory that's not permanently mapped is called
1252 "high memory".
1254 If you are compiling a kernel which will never run on a machine with
1255 more than 1 Gigabyte total physical RAM, answer "off" here (default
1256 choice and suitable for most users). This will result in a "3GB/1GB"
1257 split: 3GB are mapped so that each process sees a 3GB virtual memory
1258 space and the remaining part of the 4GB virtual memory space is used
1259 by the kernel to permanently map as much physical memory as
1260 possible.
1262 If the machine has between 1 and 4 Gigabytes physical RAM, then
1263 answer "4GB" here.
1265 If more than 4 Gigabytes is used then answer "64GB" here. This
1266 selection turns Intel PAE (Physical Address Extension) mode on.
1267 PAE implements 3-level paging on IA32 processors. PAE is fully
1268 supported by Linux, PAE mode is implemented on all recent Intel
1269 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1270 then the kernel will not boot on CPUs that don't support PAE!
1272 The actual amount of total physical memory will either be
1273 auto detected or can be forced by using a kernel command line option
1274 such as "mem=256M". (Try "man bootparam" or see the documentation of
1275 your boot loader (lilo or loadlin) about how to pass options to the
1276 kernel at boot time.)
1278 If unsure, say "off".
1280 config HIGHMEM4G
1281 bool "4GB"
1282 ---help---
1283 Select this if you have a 32-bit processor and between 1 and 4
1284 gigabytes of physical RAM.
1286 config HIGHMEM64G
1287 bool "64GB"
1288 depends on !M486
1289 select X86_PAE
1290 ---help---
1291 Select this if you have a 32-bit processor and more than 4
1292 gigabytes of physical RAM.
1294 endchoice
1296 choice
1297 prompt "Memory split" if EXPERT
1298 default VMSPLIT_3G
1299 depends on X86_32
1300 ---help---
1301 Select the desired split between kernel and user memory.
1303 If the address range available to the kernel is less than the
1304 physical memory installed, the remaining memory will be available
1305 as "high memory". Accessing high memory is a little more costly
1306 than low memory, as it needs to be mapped into the kernel first.
1307 Note that increasing the kernel address space limits the range
1308 available to user programs, making the address space there
1309 tighter. Selecting anything other than the default 3G/1G split
1310 will also likely make your kernel incompatible with binary-only
1311 kernel modules.
1313 If you are not absolutely sure what you are doing, leave this
1314 option alone!
1316 config VMSPLIT_3G
1317 bool "3G/1G user/kernel split"
1318 config VMSPLIT_3G_OPT
1319 depends on !X86_PAE
1320 bool "3G/1G user/kernel split (for full 1G low memory)"
1321 config VMSPLIT_2G
1322 bool "2G/2G user/kernel split"
1323 config VMSPLIT_2G_OPT
1324 depends on !X86_PAE
1325 bool "2G/2G user/kernel split (for full 2G low memory)"
1326 config VMSPLIT_1G
1327 bool "1G/3G user/kernel split"
1328 endchoice
1330 config PAGE_OFFSET
1331 hex
1332 default 0xB0000000 if VMSPLIT_3G_OPT
1333 default 0x80000000 if VMSPLIT_2G
1334 default 0x78000000 if VMSPLIT_2G_OPT
1335 default 0x40000000 if VMSPLIT_1G
1336 default 0xC0000000
1337 depends on X86_32
1339 config HIGHMEM
1340 def_bool y
1341 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1343 config X86_PAE
1344 bool "PAE (Physical Address Extension) Support"
1345 depends on X86_32 && !HIGHMEM4G
1346 select SWIOTLB
1347 ---help---
1348 PAE is required for NX support, and furthermore enables
1349 larger swapspace support for non-overcommit purposes. It
1350 has the cost of more pagetable lookup overhead, and also
1351 consumes more pagetable space per process.
1353 config ARCH_PHYS_ADDR_T_64BIT
1354 def_bool y
1355 depends on X86_64 || X86_PAE
1357 config ARCH_DMA_ADDR_T_64BIT
1358 def_bool y
1359 depends on X86_64 || HIGHMEM64G
1361 config X86_DIRECT_GBPAGES
1362 def_bool y
1363 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1364 ---help---
1365 Certain kernel features effectively disable kernel
1366 linear 1 GB mappings (even if the CPU otherwise
1367 supports them), so don't confuse the user by printing
1368 that we have them enabled.
1370 # Common NUMA Features
1371 config NUMA
1372 bool "Numa Memory Allocation and Scheduler Support"
1373 depends on SMP
1374 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1375 default y if X86_BIGSMP
1376 ---help---
1377 Enable NUMA (Non Uniform Memory Access) support.
1379 The kernel will try to allocate memory used by a CPU on the
1380 local memory controller of the CPU and add some more
1381 NUMA awareness to the kernel.
1383 For 64-bit this is recommended if the system is Intel Core i7
1384 (or later), AMD Opteron, or EM64T NUMA.
1386 For 32-bit this is only needed if you boot a 32-bit
1387 kernel on a 64-bit NUMA platform.
1389 Otherwise, you should say N.
1391 config AMD_NUMA
1392 def_bool y
1393 prompt "Old style AMD Opteron NUMA detection"
1394 depends on X86_64 && NUMA && PCI
1395 ---help---
1396 Enable AMD NUMA node topology detection. You should say Y here if
1397 you have a multi processor AMD system. This uses an old method to
1398 read the NUMA configuration directly from the builtin Northbridge
1399 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1400 which also takes priority if both are compiled in.
1402 config X86_64_ACPI_NUMA
1403 def_bool y
1404 prompt "ACPI NUMA detection"
1405 depends on X86_64 && NUMA && ACPI && PCI
1406 select ACPI_NUMA
1407 ---help---
1408 Enable ACPI SRAT based node topology detection.
1410 # Some NUMA nodes have memory ranges that span
1411 # other nodes. Even though a pfn is valid and
1412 # between a node's start and end pfns, it may not
1413 # reside on that node. See memmap_init_zone()
1414 # for details.
1415 config NODES_SPAN_OTHER_NODES
1416 def_bool y
1417 depends on X86_64_ACPI_NUMA
1419 config NUMA_EMU
1420 bool "NUMA emulation"
1421 depends on NUMA
1422 ---help---
1423 Enable NUMA emulation. A flat machine will be split
1424 into virtual nodes when booted with "numa=fake=N", where N is the
1425 number of nodes. This is only useful for debugging.
1427 config NODES_SHIFT
1428 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1429 range 1 10
1430 default "10" if MAXSMP
1431 default "6" if X86_64
1432 default "3"
1433 depends on NEED_MULTIPLE_NODES
1434 ---help---
1435 Specify the maximum number of NUMA Nodes available on the target
1436 system. Increases memory reserved to accommodate various tables.
1438 config ARCH_HAVE_MEMORY_PRESENT
1439 def_bool y
1440 depends on X86_32 && DISCONTIGMEM
1442 config NEED_NODE_MEMMAP_SIZE
1443 def_bool y
1444 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1446 config ARCH_FLATMEM_ENABLE
1447 def_bool y
1448 depends on X86_32 && !NUMA
1450 config ARCH_DISCONTIGMEM_ENABLE
1451 def_bool y
1452 depends on NUMA && X86_32
1454 config ARCH_DISCONTIGMEM_DEFAULT
1455 def_bool y
1456 depends on NUMA && X86_32
1458 config ARCH_SPARSEMEM_ENABLE
1459 def_bool y
1460 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1461 select SPARSEMEM_STATIC if X86_32
1462 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1464 config ARCH_SPARSEMEM_DEFAULT
1465 def_bool y
1466 depends on X86_64
1468 config ARCH_SELECT_MEMORY_MODEL
1469 def_bool y
1470 depends on ARCH_SPARSEMEM_ENABLE
1472 config ARCH_MEMORY_PROBE
1473 bool "Enable sysfs memory/probe interface"
1474 depends on X86_64 && MEMORY_HOTPLUG
1475 help
1476 This option enables a sysfs memory/probe interface for testing.
1477 See Documentation/memory-hotplug.txt for more information.
1478 If you are unsure how to answer this question, answer N.
1480 config ARCH_PROC_KCORE_TEXT
1481 def_bool y
1482 depends on X86_64 && PROC_KCORE
1484 config ILLEGAL_POINTER_VALUE
1485 hex
1486 default 0 if X86_32
1487 default 0xdead000000000000 if X86_64
1489 source "mm/Kconfig"
1491 config X86_PMEM_LEGACY_DEVICE
1492 bool
1494 config X86_PMEM_LEGACY
1495 tristate "Support non-standard NVDIMMs and ADR protected memory"
1496 depends on PHYS_ADDR_T_64BIT
1497 depends on BLK_DEV
1498 select X86_PMEM_LEGACY_DEVICE
1499 select LIBNVDIMM
1500 help
1501 Treat memory marked using the non-standard e820 type of 12 as used
1502 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1503 The kernel will offer these regions to the 'pmem' driver so
1504 they can be used for persistent storage.
1506 Say Y if unsure.
1508 config HIGHPTE
1509 bool "Allocate 3rd-level pagetables from highmem"
1510 depends on HIGHMEM
1511 ---help---
1512 The VM uses one page table entry for each page of physical memory.
1513 For systems with a lot of RAM, this can be wasteful of precious
1514 low memory. Setting this option will put user-space page table
1515 entries in high memory.
1517 config X86_CHECK_BIOS_CORRUPTION
1518 bool "Check for low memory corruption"
1519 ---help---
1520 Periodically check for memory corruption in low memory, which
1521 is suspected to be caused by BIOS. Even when enabled in the
1522 configuration, it is disabled at runtime. Enable it by
1523 setting "memory_corruption_check=1" on the kernel command
1524 line. By default it scans the low 64k of memory every 60
1525 seconds; see the memory_corruption_check_size and
1526 memory_corruption_check_period parameters in
1527 Documentation/kernel-parameters.txt to adjust this.
1529 When enabled with the default parameters, this option has
1530 almost no overhead, as it reserves a relatively small amount
1531 of memory and scans it infrequently. It both detects corruption
1532 and prevents it from affecting the running system.
1534 It is, however, intended as a diagnostic tool; if repeatable
1535 BIOS-originated corruption always affects the same memory,
1536 you can use memmap= to prevent the kernel from using that
1537 memory.
1539 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1540 bool "Set the default setting of memory_corruption_check"
1541 depends on X86_CHECK_BIOS_CORRUPTION
1542 default y
1543 ---help---
1544 Set whether the default state of memory_corruption_check is
1545 on or off.
1547 config X86_RESERVE_LOW
1548 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1549 default 64
1550 range 4 640
1551 ---help---
1552 Specify the amount of low memory to reserve for the BIOS.
1554 The first page contains BIOS data structures that the kernel
1555 must not use, so that page must always be reserved.
1557 By default we reserve the first 64K of physical RAM, as a
1558 number of BIOSes are known to corrupt that memory range
1559 during events such as suspend/resume or monitor cable
1560 insertion, so it must not be used by the kernel.
1562 You can set this to 4 if you are absolutely sure that you
1563 trust the BIOS to get all its memory reservations and usages
1564 right. If you know your BIOS have problems beyond the
1565 default 64K area, you can set this to 640 to avoid using the
1566 entire low memory range.
1568 If you have doubts about the BIOS (e.g. suspend/resume does
1569 not work or there's kernel crashes after certain hardware
1570 hotplug events) then you might want to enable
1571 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1572 typical corruption patterns.
1574 Leave this to the default value of 64 if you are unsure.
1576 config MATH_EMULATION
1577 bool
1578 depends on MODIFY_LDT_SYSCALL
1579 prompt "Math emulation" if X86_32
1580 ---help---
1581 Linux can emulate a math coprocessor (used for floating point
1582 operations) if you don't have one. 486DX and Pentium processors have
1583 a math coprocessor built in, 486SX and 386 do not, unless you added
1584 a 487DX or 387, respectively. (The messages during boot time can
1585 give you some hints here ["man dmesg"].) Everyone needs either a
1586 coprocessor or this emulation.
1588 If you don't have a math coprocessor, you need to say Y here; if you
1589 say Y here even though you have a coprocessor, the coprocessor will
1590 be used nevertheless. (This behavior can be changed with the kernel
1591 command line option "no387", which comes handy if your coprocessor
1592 is broken. Try "man bootparam" or see the documentation of your boot
1593 loader (lilo or loadlin) about how to pass options to the kernel at
1594 boot time.) This means that it is a good idea to say Y here if you
1595 intend to use this kernel on different machines.
1597 More information about the internals of the Linux math coprocessor
1598 emulation can be found in <file:arch/x86/math-emu/README>.
1600 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1601 kernel, it won't hurt.
1603 config MTRR
1604 def_bool y
1605 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1606 ---help---
1607 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1608 the Memory Type Range Registers (MTRRs) may be used to control
1609 processor access to memory ranges. This is most useful if you have
1610 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1611 allows bus write transfers to be combined into a larger transfer
1612 before bursting over the PCI/AGP bus. This can increase performance
1613 of image write operations 2.5 times or more. Saying Y here creates a
1614 /proc/mtrr file which may be used to manipulate your processor's
1615 MTRRs. Typically the X server should use this.
1617 This code has a reasonably generic interface so that similar
1618 control registers on other processors can be easily supported
1619 as well:
1621 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1622 Registers (ARRs) which provide a similar functionality to MTRRs. For
1623 these, the ARRs are used to emulate the MTRRs.
1624 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1625 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1626 write-combining. All of these processors are supported by this code
1627 and it makes sense to say Y here if you have one of them.
1629 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1630 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1631 can lead to all sorts of problems, so it's good to say Y here.
1633 You can safely say Y even if your machine doesn't have MTRRs, you'll
1634 just add about 9 KB to your kernel.
1636 See <file:Documentation/x86/mtrr.txt> for more information.
1638 config MTRR_SANITIZER
1639 def_bool y
1640 prompt "MTRR cleanup support"
1641 depends on MTRR
1642 ---help---
1643 Convert MTRR layout from continuous to discrete, so X drivers can
1644 add writeback entries.
1646 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1647 The largest mtrr entry size for a continuous block can be set with
1648 mtrr_chunk_size.
1650 If unsure, say Y.
1652 config MTRR_SANITIZER_ENABLE_DEFAULT
1653 int "MTRR cleanup enable value (0-1)"
1654 range 0 1
1655 default "0"
1656 depends on MTRR_SANITIZER
1657 ---help---
1658 Enable mtrr cleanup default value
1660 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1661 int "MTRR cleanup spare reg num (0-7)"
1662 range 0 7
1663 default "1"
1664 depends on MTRR_SANITIZER
1665 ---help---
1666 mtrr cleanup spare entries default, it can be changed via
1667 mtrr_spare_reg_nr=N on the kernel command line.
1669 config X86_PAT
1670 def_bool y
1671 prompt "x86 PAT support" if EXPERT
1672 depends on MTRR
1673 ---help---
1674 Use PAT attributes to setup page level cache control.
1676 PATs are the modern equivalents of MTRRs and are much more
1677 flexible than MTRRs.
1679 Say N here if you see bootup problems (boot crash, boot hang,
1680 spontaneous reboots) or a non-working video driver.
1682 If unsure, say Y.
1684 config ARCH_USES_PG_UNCACHED
1685 def_bool y
1686 depends on X86_PAT
1688 config ARCH_RANDOM
1689 def_bool y
1690 prompt "x86 architectural random number generator" if EXPERT
1691 ---help---
1692 Enable the x86 architectural RDRAND instruction
1693 (Intel Bull Mountain technology) to generate random numbers.
1694 If supported, this is a high bandwidth, cryptographically
1695 secure hardware random number generator.
1697 config X86_SMAP
1698 def_bool y
1699 prompt "Supervisor Mode Access Prevention" if EXPERT
1700 ---help---
1701 Supervisor Mode Access Prevention (SMAP) is a security
1702 feature in newer Intel processors. There is a small
1703 performance cost if this enabled and turned on; there is
1704 also a small increase in the kernel size if this is enabled.
1706 If unsure, say Y.
1708 config X86_INTEL_MPX
1709 prompt "Intel MPX (Memory Protection Extensions)"
1710 def_bool n
1711 depends on CPU_SUP_INTEL
1712 ---help---
1713 MPX provides hardware features that can be used in
1714 conjunction with compiler-instrumented code to check
1715 memory references. It is designed to detect buffer
1716 overflow or underflow bugs.
1718 This option enables running applications which are
1719 instrumented or otherwise use MPX. It does not use MPX
1720 itself inside the kernel or to protect the kernel
1721 against bad memory references.
1723 Enabling this option will make the kernel larger:
1724 ~8k of kernel text and 36 bytes of data on a 64-bit
1725 defconfig. It adds a long to the 'mm_struct' which
1726 will increase the kernel memory overhead of each
1727 process and adds some branches to paths used during
1728 exec() and munmap().
1730 For details, see Documentation/x86/intel_mpx.txt
1732 If unsure, say N.
1734 config X86_INTEL_MEMORY_PROTECTION_KEYS
1735 prompt "Intel Memory Protection Keys"
1736 def_bool y
1737 # Note: only available in 64-bit mode
1738 depends on CPU_SUP_INTEL && X86_64
1739 ---help---
1740 Memory Protection Keys provides a mechanism for enforcing
1741 page-based protections, but without requiring modification of the
1742 page tables when an application changes protection domains.
1744 For details, see Documentation/x86/protection-keys.txt
1746 If unsure, say y.
1748 config EFI
1749 bool "EFI runtime service support"
1750 depends on ACPI
1751 select UCS2_STRING
1752 select EFI_RUNTIME_WRAPPERS
1753 ---help---
1754 This enables the kernel to use EFI runtime services that are
1755 available (such as the EFI variable services).
1757 This option is only useful on systems that have EFI firmware.
1758 In addition, you should use the latest ELILO loader available
1759 at <http://elilo.sourceforge.net> in order to take advantage
1760 of EFI runtime services. However, even with this option, the
1761 resultant kernel should continue to boot on existing non-EFI
1762 platforms.
1764 config EFI_STUB
1765 bool "EFI stub support"
1766 depends on EFI && !X86_USE_3DNOW
1767 select RELOCATABLE
1768 ---help---
1769 This kernel feature allows a bzImage to be loaded directly
1770 by EFI firmware without the use of a bootloader.
1772 See Documentation/efi-stub.txt for more information.
1774 config EFI_MIXED
1775 bool "EFI mixed-mode support"
1776 depends on EFI_STUB && X86_64
1777 ---help---
1778 Enabling this feature allows a 64-bit kernel to be booted
1779 on a 32-bit firmware, provided that your CPU supports 64-bit
1780 mode.
1782 Note that it is not possible to boot a mixed-mode enabled
1783 kernel via the EFI boot stub - a bootloader that supports
1784 the EFI handover protocol must be used.
1786 If unsure, say N.
1788 config SECCOMP
1789 def_bool y
1790 prompt "Enable seccomp to safely compute untrusted bytecode"
1791 ---help---
1792 This kernel feature is useful for number crunching applications
1793 that may need to compute untrusted bytecode during their
1794 execution. By using pipes or other transports made available to
1795 the process as file descriptors supporting the read/write
1796 syscalls, it's possible to isolate those applications in
1797 their own address space using seccomp. Once seccomp is
1798 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1799 and the task is only allowed to execute a few safe syscalls
1800 defined by each seccomp mode.
1802 If unsure, say Y. Only embedded should say N here.
1804 source kernel/Kconfig.hz
1806 config KEXEC
1807 bool "kexec system call"
1808 select KEXEC_CORE
1809 ---help---
1810 kexec is a system call that implements the ability to shutdown your
1811 current kernel, and to start another kernel. It is like a reboot
1812 but it is independent of the system firmware. And like a reboot
1813 you can start any kernel with it, not just Linux.
1815 The name comes from the similarity to the exec system call.
1817 It is an ongoing process to be certain the hardware in a machine
1818 is properly shutdown, so do not be surprised if this code does not
1819 initially work for you. As of this writing the exact hardware
1820 interface is strongly in flux, so no good recommendation can be
1821 made.
1823 config KEXEC_FILE
1824 bool "kexec file based system call"
1825 select KEXEC_CORE
1826 select BUILD_BIN2C
1827 depends on X86_64
1828 depends on CRYPTO=y
1829 depends on CRYPTO_SHA256=y
1830 ---help---
1831 This is new version of kexec system call. This system call is
1832 file based and takes file descriptors as system call argument
1833 for kernel and initramfs as opposed to list of segments as
1834 accepted by previous system call.
1836 config KEXEC_VERIFY_SIG
1837 bool "Verify kernel signature during kexec_file_load() syscall"
1838 depends on KEXEC_FILE
1839 ---help---
1840 This option makes kernel signature verification mandatory for
1841 the kexec_file_load() syscall.
1843 In addition to that option, you need to enable signature
1844 verification for the corresponding kernel image type being
1845 loaded in order for this to work.
1847 config KEXEC_BZIMAGE_VERIFY_SIG
1848 bool "Enable bzImage signature verification support"
1849 depends on KEXEC_VERIFY_SIG
1850 depends on SIGNED_PE_FILE_VERIFICATION
1851 select SYSTEM_TRUSTED_KEYRING
1852 ---help---
1853 Enable bzImage signature verification support.
1855 config CRASH_DUMP
1856 bool "kernel crash dumps"
1857 depends on X86_64 || (X86_32 && HIGHMEM)
1858 ---help---
1859 Generate crash dump after being started by kexec.
1860 This should be normally only set in special crash dump kernels
1861 which are loaded in the main kernel with kexec-tools into
1862 a specially reserved region and then later executed after
1863 a crash by kdump/kexec. The crash dump kernel must be compiled
1864 to a memory address not used by the main kernel or BIOS using
1865 PHYSICAL_START, or it must be built as a relocatable image
1866 (CONFIG_RELOCATABLE=y).
1867 For more details see Documentation/kdump/kdump.txt
1869 config KEXEC_JUMP
1870 bool "kexec jump"
1871 depends on KEXEC && HIBERNATION
1872 ---help---
1873 Jump between original kernel and kexeced kernel and invoke
1874 code in physical address mode via KEXEC
1876 config PHYSICAL_START
1877 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1878 default "0x1000000"
1879 ---help---
1880 This gives the physical address where the kernel is loaded.
1882 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1883 bzImage will decompress itself to above physical address and
1884 run from there. Otherwise, bzImage will run from the address where
1885 it has been loaded by the boot loader and will ignore above physical
1886 address.
1888 In normal kdump cases one does not have to set/change this option
1889 as now bzImage can be compiled as a completely relocatable image
1890 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1891 address. This option is mainly useful for the folks who don't want
1892 to use a bzImage for capturing the crash dump and want to use a
1893 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1894 to be specifically compiled to run from a specific memory area
1895 (normally a reserved region) and this option comes handy.
1897 So if you are using bzImage for capturing the crash dump,
1898 leave the value here unchanged to 0x1000000 and set
1899 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1900 for capturing the crash dump change this value to start of
1901 the reserved region. In other words, it can be set based on
1902 the "X" value as specified in the "crashkernel=YM@XM"
1903 command line boot parameter passed to the panic-ed
1904 kernel. Please take a look at Documentation/kdump/kdump.txt
1905 for more details about crash dumps.
1907 Usage of bzImage for capturing the crash dump is recommended as
1908 one does not have to build two kernels. Same kernel can be used
1909 as production kernel and capture kernel. Above option should have
1910 gone away after relocatable bzImage support is introduced. But it
1911 is present because there are users out there who continue to use
1912 vmlinux for dump capture. This option should go away down the
1913 line.
1915 Don't change this unless you know what you are doing.
1917 config RELOCATABLE
1918 bool "Build a relocatable kernel"
1919 default y
1920 ---help---
1921 This builds a kernel image that retains relocation information
1922 so it can be loaded someplace besides the default 1MB.
1923 The relocations tend to make the kernel binary about 10% larger,
1924 but are discarded at runtime.
1926 One use is for the kexec on panic case where the recovery kernel
1927 must live at a different physical address than the primary
1928 kernel.
1930 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1931 it has been loaded at and the compile time physical address
1932 (CONFIG_PHYSICAL_START) is used as the minimum location.
1934 config RANDOMIZE_BASE
1935 bool "Randomize the address of the kernel image"
1936 depends on RELOCATABLE
1937 default n
1938 ---help---
1939 Randomizes the physical and virtual address at which the
1940 kernel image is decompressed, as a security feature that
1941 deters exploit attempts relying on knowledge of the location
1942 of kernel internals.
1944 Entropy is generated using the RDRAND instruction if it is
1945 supported. If RDTSC is supported, it is used as well. If
1946 neither RDRAND nor RDTSC are supported, then randomness is
1947 read from the i8254 timer.
1949 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1950 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1951 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1952 minimum of 2MiB, only 10 bits of entropy is theoretically
1953 possible. At best, due to page table layouts, 64-bit can use
1954 9 bits of entropy and 32-bit uses 8 bits.
1956 If unsure, say N.
1958 config RANDOMIZE_BASE_MAX_OFFSET
1959 hex "Maximum kASLR offset allowed" if EXPERT
1960 depends on RANDOMIZE_BASE
1961 range 0x0 0x20000000 if X86_32
1962 default "0x20000000" if X86_32
1963 range 0x0 0x40000000 if X86_64
1964 default "0x40000000" if X86_64
1965 ---help---
1966 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1967 memory is used to determine the maximal offset in bytes that will
1968 be applied to the kernel when kernel Address Space Layout
1969 Randomization (kASLR) is active. This must be a multiple of
1970 PHYSICAL_ALIGN.
1972 On 32-bit this is limited to 512MiB by page table layouts. The
1973 default is 512MiB.
1975 On 64-bit this is limited by how the kernel fixmap page table is
1976 positioned, so this cannot be larger than 1GiB currently. Without
1977 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1978 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1979 modules area will shrink to compensate, up to the current maximum
1980 1GiB to 1GiB split. The default is 1GiB.
1982 If unsure, leave at the default value.
1984 # Relocation on x86 needs some additional build support
1985 config X86_NEED_RELOCS
1986 def_bool y
1987 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1989 config PHYSICAL_ALIGN
1990 hex "Alignment value to which kernel should be aligned"
1991 default "0x200000"
1992 range 0x2000 0x1000000 if X86_32
1993 range 0x200000 0x1000000 if X86_64
1994 ---help---
1995 This value puts the alignment restrictions on physical address
1996 where kernel is loaded and run from. Kernel is compiled for an
1997 address which meets above alignment restriction.
1999 If bootloader loads the kernel at a non-aligned address and
2000 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2001 address aligned to above value and run from there.
2003 If bootloader loads the kernel at a non-aligned address and
2004 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2005 load address and decompress itself to the address it has been
2006 compiled for and run from there. The address for which kernel is
2007 compiled already meets above alignment restrictions. Hence the
2008 end result is that kernel runs from a physical address meeting
2009 above alignment restrictions.
2011 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2012 this value must be a multiple of 0x200000.
2014 Don't change this unless you know what you are doing.
2016 config HOTPLUG_CPU
2017 bool "Support for hot-pluggable CPUs"
2018 depends on SMP
2019 ---help---
2020 Say Y here to allow turning CPUs off and on. CPUs can be
2021 controlled through /sys/devices/system/cpu.
2022 ( Note: power management support will enable this option
2023 automatically on SMP systems. )
2024 Say N if you want to disable CPU hotplug.
2026 config BOOTPARAM_HOTPLUG_CPU0
2027 bool "Set default setting of cpu0_hotpluggable"
2028 default n
2029 depends on HOTPLUG_CPU
2030 ---help---
2031 Set whether default state of cpu0_hotpluggable is on or off.
2033 Say Y here to enable CPU0 hotplug by default. If this switch
2034 is turned on, there is no need to give cpu0_hotplug kernel
2035 parameter and the CPU0 hotplug feature is enabled by default.
2037 Please note: there are two known CPU0 dependencies if you want
2038 to enable the CPU0 hotplug feature either by this switch or by
2039 cpu0_hotplug kernel parameter.
2041 First, resume from hibernate or suspend always starts from CPU0.
2042 So hibernate and suspend are prevented if CPU0 is offline.
2044 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2045 offline if any interrupt can not migrate out of CPU0. There may
2046 be other CPU0 dependencies.
2048 Please make sure the dependencies are under your control before
2049 you enable this feature.
2051 Say N if you don't want to enable CPU0 hotplug feature by default.
2052 You still can enable the CPU0 hotplug feature at boot by kernel
2053 parameter cpu0_hotplug.
2055 config DEBUG_HOTPLUG_CPU0
2056 def_bool n
2057 prompt "Debug CPU0 hotplug"
2058 depends on HOTPLUG_CPU
2059 ---help---
2060 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2061 soon as possible and boots up userspace with CPU0 offlined. User
2062 can online CPU0 back after boot time.
2064 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2065 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2066 compilation or giving cpu0_hotplug kernel parameter at boot.
2068 If unsure, say N.
2070 config COMPAT_VDSO
2071 def_bool n
2072 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2073 depends on X86_32 || IA32_EMULATION
2074 ---help---
2075 Certain buggy versions of glibc will crash if they are
2076 presented with a 32-bit vDSO that is not mapped at the address
2077 indicated in its segment table.
2079 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2080 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2081 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2082 the only released version with the bug, but OpenSUSE 9
2083 contains a buggy "glibc 2.3.2".
2085 The symptom of the bug is that everything crashes on startup, saying:
2086 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2088 Saying Y here changes the default value of the vdso32 boot
2089 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2090 This works around the glibc bug but hurts performance.
2092 If unsure, say N: if you are compiling your own kernel, you
2093 are unlikely to be using a buggy version of glibc.
2095 choice
2096 prompt "vsyscall table for legacy applications"
2097 depends on X86_64
2098 default LEGACY_VSYSCALL_EMULATE
2099 help
2100 Legacy user code that does not know how to find the vDSO expects
2101 to be able to issue three syscalls by calling fixed addresses in
2102 kernel space. Since this location is not randomized with ASLR,
2103 it can be used to assist security vulnerability exploitation.
2105 This setting can be changed at boot time via the kernel command
2106 line parameter vsyscall=[native|emulate|none].
2108 On a system with recent enough glibc (2.14 or newer) and no
2109 static binaries, you can say None without a performance penalty
2110 to improve security.
2112 If unsure, select "Emulate".
2114 config LEGACY_VSYSCALL_NATIVE
2115 bool "Native"
2116 help
2117 Actual executable code is located in the fixed vsyscall
2118 address mapping, implementing time() efficiently. Since
2119 this makes the mapping executable, it can be used during
2120 security vulnerability exploitation (traditionally as
2121 ROP gadgets). This configuration is not recommended.
2123 config LEGACY_VSYSCALL_EMULATE
2124 bool "Emulate"
2125 help
2126 The kernel traps and emulates calls into the fixed
2127 vsyscall address mapping. This makes the mapping
2128 non-executable, but it still contains known contents,
2129 which could be used in certain rare security vulnerability
2130 exploits. This configuration is recommended when userspace
2131 still uses the vsyscall area.
2133 config LEGACY_VSYSCALL_NONE
2134 bool "None"
2135 help
2136 There will be no vsyscall mapping at all. This will
2137 eliminate any risk of ASLR bypass due to the vsyscall
2138 fixed address mapping. Attempts to use the vsyscalls
2139 will be reported to dmesg, so that either old or
2140 malicious userspace programs can be identified.
2142 endchoice
2144 config CMDLINE_BOOL
2145 bool "Built-in kernel command line"
2146 ---help---
2147 Allow for specifying boot arguments to the kernel at
2148 build time. On some systems (e.g. embedded ones), it is
2149 necessary or convenient to provide some or all of the
2150 kernel boot arguments with the kernel itself (that is,
2151 to not rely on the boot loader to provide them.)
2153 To compile command line arguments into the kernel,
2154 set this option to 'Y', then fill in the
2155 boot arguments in CONFIG_CMDLINE.
2157 Systems with fully functional boot loaders (i.e. non-embedded)
2158 should leave this option set to 'N'.
2160 config CMDLINE
2161 string "Built-in kernel command string"
2162 depends on CMDLINE_BOOL
2163 default ""
2164 ---help---
2165 Enter arguments here that should be compiled into the kernel
2166 image and used at boot time. If the boot loader provides a
2167 command line at boot time, it is appended to this string to
2168 form the full kernel command line, when the system boots.
2170 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2171 change this behavior.
2173 In most cases, the command line (whether built-in or provided
2174 by the boot loader) should specify the device for the root
2175 file system.
2177 config CMDLINE_OVERRIDE
2178 bool "Built-in command line overrides boot loader arguments"
2179 depends on CMDLINE_BOOL
2180 ---help---
2181 Set this option to 'Y' to have the kernel ignore the boot loader
2182 command line, and use ONLY the built-in command line.
2184 This is used to work around broken boot loaders. This should
2185 be set to 'N' under normal conditions.
2187 config MODIFY_LDT_SYSCALL
2188 bool "Enable the LDT (local descriptor table)" if EXPERT
2189 default y
2190 ---help---
2191 Linux can allow user programs to install a per-process x86
2192 Local Descriptor Table (LDT) using the modify_ldt(2) system
2193 call. This is required to run 16-bit or segmented code such as
2194 DOSEMU or some Wine programs. It is also used by some very old
2195 threading libraries.
2197 Enabling this feature adds a small amount of overhead to
2198 context switches and increases the low-level kernel attack
2199 surface. Disabling it removes the modify_ldt(2) system call.
2201 Saying 'N' here may make sense for embedded or server kernels.
2203 source "kernel/livepatch/Kconfig"
2205 endmenu
2207 config ARCH_ENABLE_MEMORY_HOTPLUG
2208 def_bool y
2209 depends on X86_64 || (X86_32 && HIGHMEM)
2211 config ARCH_ENABLE_MEMORY_HOTREMOVE
2212 def_bool y
2213 depends on MEMORY_HOTPLUG
2215 config USE_PERCPU_NUMA_NODE_ID
2216 def_bool y
2217 depends on NUMA
2219 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2220 def_bool y
2221 depends on X86_64 || X86_PAE
2223 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2224 def_bool y
2225 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2227 menu "Power management and ACPI options"
2229 config ARCH_HIBERNATION_HEADER
2230 def_bool y
2231 depends on X86_64 && HIBERNATION
2233 source "kernel/power/Kconfig"
2235 source "drivers/acpi/Kconfig"
2237 source "drivers/sfi/Kconfig"
2239 config X86_APM_BOOT
2240 def_bool y
2241 depends on APM
2243 menuconfig APM
2244 tristate "APM (Advanced Power Management) BIOS support"
2245 depends on X86_32 && PM_SLEEP
2246 ---help---
2247 APM is a BIOS specification for saving power using several different
2248 techniques. This is mostly useful for battery powered laptops with
2249 APM compliant BIOSes. If you say Y here, the system time will be
2250 reset after a RESUME operation, the /proc/apm device will provide
2251 battery status information, and user-space programs will receive
2252 notification of APM "events" (e.g. battery status change).
2254 If you select "Y" here, you can disable actual use of the APM
2255 BIOS by passing the "apm=off" option to the kernel at boot time.
2257 Note that the APM support is almost completely disabled for
2258 machines with more than one CPU.
2260 In order to use APM, you will need supporting software. For location
2261 and more information, read <file:Documentation/power/apm-acpi.txt>
2262 and the Battery Powered Linux mini-HOWTO, available from
2263 <http://www.tldp.org/docs.html#howto>.
2265 This driver does not spin down disk drives (see the hdparm(8)
2266 manpage ("man 8 hdparm") for that), and it doesn't turn off
2267 VESA-compliant "green" monitors.
2269 This driver does not support the TI 4000M TravelMate and the ACER
2270 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2271 desktop machines also don't have compliant BIOSes, and this driver
2272 may cause those machines to panic during the boot phase.
2274 Generally, if you don't have a battery in your machine, there isn't
2275 much point in using this driver and you should say N. If you get
2276 random kernel OOPSes or reboots that don't seem to be related to
2277 anything, try disabling/enabling this option (or disabling/enabling
2278 APM in your BIOS).
2280 Some other things you should try when experiencing seemingly random,
2281 "weird" problems:
2283 1) make sure that you have enough swap space and that it is
2284 enabled.
2285 2) pass the "no-hlt" option to the kernel
2286 3) switch on floating point emulation in the kernel and pass
2287 the "no387" option to the kernel
2288 4) pass the "floppy=nodma" option to the kernel
2289 5) pass the "mem=4M" option to the kernel (thereby disabling
2290 all but the first 4 MB of RAM)
2291 6) make sure that the CPU is not over clocked.
2292 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2293 8) disable the cache from your BIOS settings
2294 9) install a fan for the video card or exchange video RAM
2295 10) install a better fan for the CPU
2296 11) exchange RAM chips
2297 12) exchange the motherboard.
2299 To compile this driver as a module, choose M here: the
2300 module will be called apm.
2302 if APM
2304 config APM_IGNORE_USER_SUSPEND
2305 bool "Ignore USER SUSPEND"
2306 ---help---
2307 This option will ignore USER SUSPEND requests. On machines with a
2308 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2309 series notebooks, it is necessary to say Y because of a BIOS bug.
2311 config APM_DO_ENABLE
2312 bool "Enable PM at boot time"
2313 ---help---
2314 Enable APM features at boot time. From page 36 of the APM BIOS
2315 specification: "When disabled, the APM BIOS does not automatically
2316 power manage devices, enter the Standby State, enter the Suspend
2317 State, or take power saving steps in response to CPU Idle calls."
2318 This driver will make CPU Idle calls when Linux is idle (unless this
2319 feature is turned off -- see "Do CPU IDLE calls", below). This
2320 should always save battery power, but more complicated APM features
2321 will be dependent on your BIOS implementation. You may need to turn
2322 this option off if your computer hangs at boot time when using APM
2323 support, or if it beeps continuously instead of suspending. Turn
2324 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2325 T400CDT. This is off by default since most machines do fine without
2326 this feature.
2328 config APM_CPU_IDLE
2329 depends on CPU_IDLE
2330 bool "Make CPU Idle calls when idle"
2331 ---help---
2332 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2333 On some machines, this can activate improved power savings, such as
2334 a slowed CPU clock rate, when the machine is idle. These idle calls
2335 are made after the idle loop has run for some length of time (e.g.,
2336 333 mS). On some machines, this will cause a hang at boot time or
2337 whenever the CPU becomes idle. (On machines with more than one CPU,
2338 this option does nothing.)
2340 config APM_DISPLAY_BLANK
2341 bool "Enable console blanking using APM"
2342 ---help---
2343 Enable console blanking using the APM. Some laptops can use this to
2344 turn off the LCD backlight when the screen blanker of the Linux
2345 virtual console blanks the screen. Note that this is only used by
2346 the virtual console screen blanker, and won't turn off the backlight
2347 when using the X Window system. This also doesn't have anything to
2348 do with your VESA-compliant power-saving monitor. Further, this
2349 option doesn't work for all laptops -- it might not turn off your
2350 backlight at all, or it might print a lot of errors to the console,
2351 especially if you are using gpm.
2353 config APM_ALLOW_INTS
2354 bool "Allow interrupts during APM BIOS calls"
2355 ---help---
2356 Normally we disable external interrupts while we are making calls to
2357 the APM BIOS as a measure to lessen the effects of a badly behaving
2358 BIOS implementation. The BIOS should reenable interrupts if it
2359 needs to. Unfortunately, some BIOSes do not -- especially those in
2360 many of the newer IBM Thinkpads. If you experience hangs when you
2361 suspend, try setting this to Y. Otherwise, say N.
2363 endif # APM
2365 source "drivers/cpufreq/Kconfig"
2367 source "drivers/cpuidle/Kconfig"
2369 source "drivers/idle/Kconfig"
2371 endmenu
2374 menu "Bus options (PCI etc.)"
2376 config PCI
2377 bool "PCI support"
2378 default y
2379 ---help---
2380 Find out whether you have a PCI motherboard. PCI is the name of a
2381 bus system, i.e. the way the CPU talks to the other stuff inside
2382 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2383 VESA. If you have PCI, say Y, otherwise N.
2385 choice
2386 prompt "PCI access mode"
2387 depends on X86_32 && PCI
2388 default PCI_GOANY
2389 ---help---
2390 On PCI systems, the BIOS can be used to detect the PCI devices and
2391 determine their configuration. However, some old PCI motherboards
2392 have BIOS bugs and may crash if this is done. Also, some embedded
2393 PCI-based systems don't have any BIOS at all. Linux can also try to
2394 detect the PCI hardware directly without using the BIOS.
2396 With this option, you can specify how Linux should detect the
2397 PCI devices. If you choose "BIOS", the BIOS will be used,
2398 if you choose "Direct", the BIOS won't be used, and if you
2399 choose "MMConfig", then PCI Express MMCONFIG will be used.
2400 If you choose "Any", the kernel will try MMCONFIG, then the
2401 direct access method and falls back to the BIOS if that doesn't
2402 work. If unsure, go with the default, which is "Any".
2404 config PCI_GOBIOS
2405 bool "BIOS"
2407 config PCI_GOMMCONFIG
2408 bool "MMConfig"
2410 config PCI_GODIRECT
2411 bool "Direct"
2413 config PCI_GOOLPC
2414 bool "OLPC XO-1"
2415 depends on OLPC
2417 config PCI_GOANY
2418 bool "Any"
2420 endchoice
2422 config PCI_BIOS
2423 def_bool y
2424 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2426 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2427 config PCI_DIRECT
2428 def_bool y
2429 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2431 config PCI_MMCONFIG
2432 def_bool y
2433 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2435 config PCI_OLPC
2436 def_bool y
2437 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2439 config PCI_XEN
2440 def_bool y
2441 depends on PCI && XEN
2442 select SWIOTLB_XEN
2444 config PCI_DOMAINS
2445 def_bool y
2446 depends on PCI
2448 config PCI_MMCONFIG
2449 bool "Support mmconfig PCI config space access"
2450 depends on X86_64 && PCI && ACPI
2452 config PCI_CNB20LE_QUIRK
2453 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2454 depends on PCI
2455 help
2456 Read the PCI windows out of the CNB20LE host bridge. This allows
2457 PCI hotplug to work on systems with the CNB20LE chipset which do
2458 not have ACPI.
2460 There's no public spec for this chipset, and this functionality
2461 is known to be incomplete.
2463 You should say N unless you know you need this.
2465 source "drivers/pci/Kconfig"
2467 # x86_64 have no ISA slots, but can have ISA-style DMA.
2468 config ISA_DMA_API
2469 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2470 default y
2471 help
2472 Enables ISA-style DMA support for devices requiring such controllers.
2473 If unsure, say Y.
2475 if X86_32
2477 config ISA
2478 bool "ISA support"
2479 ---help---
2480 Find out whether you have ISA slots on your motherboard. ISA is the
2481 name of a bus system, i.e. the way the CPU talks to the other stuff
2482 inside your box. Other bus systems are PCI, EISA, MicroChannel
2483 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2484 newer boards don't support it. If you have ISA, say Y, otherwise N.
2486 config EISA
2487 bool "EISA support"
2488 depends on ISA
2489 ---help---
2490 The Extended Industry Standard Architecture (EISA) bus was
2491 developed as an open alternative to the IBM MicroChannel bus.
2493 The EISA bus provided some of the features of the IBM MicroChannel
2494 bus while maintaining backward compatibility with cards made for
2495 the older ISA bus. The EISA bus saw limited use between 1988 and
2496 1995 when it was made obsolete by the PCI bus.
2498 Say Y here if you are building a kernel for an EISA-based machine.
2500 Otherwise, say N.
2502 source "drivers/eisa/Kconfig"
2504 config SCx200
2505 tristate "NatSemi SCx200 support"
2506 ---help---
2507 This provides basic support for National Semiconductor's
2508 (now AMD's) Geode processors. The driver probes for the
2509 PCI-IDs of several on-chip devices, so its a good dependency
2510 for other scx200_* drivers.
2512 If compiled as a module, the driver is named scx200.
2514 config SCx200HR_TIMER
2515 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2516 depends on SCx200
2517 default y
2518 ---help---
2519 This driver provides a clocksource built upon the on-chip
2520 27MHz high-resolution timer. Its also a workaround for
2521 NSC Geode SC-1100's buggy TSC, which loses time when the
2522 processor goes idle (as is done by the scheduler). The
2523 other workaround is idle=poll boot option.
2525 config OLPC
2526 bool "One Laptop Per Child support"
2527 depends on !X86_PAE
2528 select GPIOLIB
2529 select OF
2530 select OF_PROMTREE
2531 select IRQ_DOMAIN
2532 ---help---
2533 Add support for detecting the unique features of the OLPC
2534 XO hardware.
2536 config OLPC_XO1_PM
2537 bool "OLPC XO-1 Power Management"
2538 depends on OLPC && MFD_CS5535 && PM_SLEEP
2539 select MFD_CORE
2540 ---help---
2541 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2543 config OLPC_XO1_RTC
2544 bool "OLPC XO-1 Real Time Clock"
2545 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2546 ---help---
2547 Add support for the XO-1 real time clock, which can be used as a
2548 programmable wakeup source.
2550 config OLPC_XO1_SCI
2551 bool "OLPC XO-1 SCI extras"
2552 depends on OLPC && OLPC_XO1_PM
2553 depends on INPUT=y
2554 select POWER_SUPPLY
2555 select GPIO_CS5535
2556 select MFD_CORE
2557 ---help---
2558 Add support for SCI-based features of the OLPC XO-1 laptop:
2559 - EC-driven system wakeups
2560 - Power button
2561 - Ebook switch
2562 - Lid switch
2563 - AC adapter status updates
2564 - Battery status updates
2566 config OLPC_XO15_SCI
2567 bool "OLPC XO-1.5 SCI extras"
2568 depends on OLPC && ACPI
2569 select POWER_SUPPLY
2570 ---help---
2571 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2572 - EC-driven system wakeups
2573 - AC adapter status updates
2574 - Battery status updates
2576 config ALIX
2577 bool "PCEngines ALIX System Support (LED setup)"
2578 select GPIOLIB
2579 ---help---
2580 This option enables system support for the PCEngines ALIX.
2581 At present this just sets up LEDs for GPIO control on
2582 ALIX2/3/6 boards. However, other system specific setup should
2583 get added here.
2585 Note: You must still enable the drivers for GPIO and LED support
2586 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2588 Note: You have to set alix.force=1 for boards with Award BIOS.
2590 config NET5501
2591 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2592 select GPIOLIB
2593 ---help---
2594 This option enables system support for the Soekris Engineering net5501.
2596 config GEOS
2597 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2598 select GPIOLIB
2599 depends on DMI
2600 ---help---
2601 This option enables system support for the Traverse Technologies GEOS.
2603 config TS5500
2604 bool "Technologic Systems TS-5500 platform support"
2605 depends on MELAN
2606 select CHECK_SIGNATURE
2607 select NEW_LEDS
2608 select LEDS_CLASS
2609 ---help---
2610 This option enables system support for the Technologic Systems TS-5500.
2612 endif # X86_32
2614 config AMD_NB
2615 def_bool y
2616 depends on CPU_SUP_AMD && PCI
2618 source "drivers/pcmcia/Kconfig"
2620 config RAPIDIO
2621 tristate "RapidIO support"
2622 depends on PCI
2623 default n
2624 help
2625 If enabled this option will include drivers and the core
2626 infrastructure code to support RapidIO interconnect devices.
2628 source "drivers/rapidio/Kconfig"
2630 config X86_SYSFB
2631 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2632 help
2633 Firmwares often provide initial graphics framebuffers so the BIOS,
2634 bootloader or kernel can show basic video-output during boot for
2635 user-guidance and debugging. Historically, x86 used the VESA BIOS
2636 Extensions and EFI-framebuffers for this, which are mostly limited
2637 to x86.
2638 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2639 framebuffers so the new generic system-framebuffer drivers can be
2640 used on x86. If the framebuffer is not compatible with the generic
2641 modes, it is adverticed as fallback platform framebuffer so legacy
2642 drivers like efifb, vesafb and uvesafb can pick it up.
2643 If this option is not selected, all system framebuffers are always
2644 marked as fallback platform framebuffers as usual.
2646 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2647 not be able to pick up generic system framebuffers if this option
2648 is selected. You are highly encouraged to enable simplefb as
2649 replacement if you select this option. simplefb can correctly deal
2650 with generic system framebuffers. But you should still keep vesafb
2651 and others enabled as fallback if a system framebuffer is
2652 incompatible with simplefb.
2654 If unsure, say Y.
2656 endmenu
2659 menu "Executable file formats / Emulations"
2661 source "fs/Kconfig.binfmt"
2663 config IA32_EMULATION
2664 bool "IA32 Emulation"
2665 depends on X86_64
2666 select BINFMT_ELF
2667 select COMPAT_BINFMT_ELF
2668 select ARCH_WANT_OLD_COMPAT_IPC
2669 ---help---
2670 Include code to run legacy 32-bit programs under a
2671 64-bit kernel. You should likely turn this on, unless you're
2672 100% sure that you don't have any 32-bit programs left.
2674 config IA32_AOUT
2675 tristate "IA32 a.out support"
2676 depends on IA32_EMULATION
2677 ---help---
2678 Support old a.out binaries in the 32bit emulation.
2680 config X86_X32
2681 bool "x32 ABI for 64-bit mode"
2682 depends on X86_64
2683 ---help---
2684 Include code to run binaries for the x32 native 32-bit ABI
2685 for 64-bit processors. An x32 process gets access to the
2686 full 64-bit register file and wide data path while leaving
2687 pointers at 32 bits for smaller memory footprint.
2689 You will need a recent binutils (2.22 or later) with
2690 elf32_x86_64 support enabled to compile a kernel with this
2691 option set.
2693 config COMPAT
2694 def_bool y
2695 depends on IA32_EMULATION || X86_X32
2697 if COMPAT
2698 config COMPAT_FOR_U64_ALIGNMENT
2699 def_bool y
2701 config SYSVIPC_COMPAT
2702 def_bool y
2703 depends on SYSVIPC
2705 config KEYS_COMPAT
2706 def_bool y
2707 depends on KEYS
2708 endif
2710 endmenu
2713 config HAVE_ATOMIC_IOMAP
2714 def_bool y
2715 depends on X86_32
2717 config X86_DEV_DMA_OPS
2718 bool
2719 depends on X86_64 || STA2X11
2721 config X86_DMA_REMAP
2722 bool
2723 depends on STA2X11
2725 config PMC_ATOM
2726 def_bool y
2727 depends on PCI
2729 config VMD
2730 depends on PCI_MSI
2731 tristate "Volume Management Device Driver"
2732 default N
2733 ---help---
2734 Adds support for the Intel Volume Management Device (VMD). VMD is a
2735 secondary PCI host bridge that allows PCI Express root ports,
2736 and devices attached to them, to be removed from the default
2737 PCI domain and placed within the VMD domain. This provides
2738 more bus resources than are otherwise possible with a
2739 single domain. If you know your system provides one of these and
2740 has devices attached to it, say Y; if you are not sure, say N.
2742 source "net/Kconfig"
2744 source "drivers/Kconfig"
2746 source "drivers/firmware/Kconfig"
2748 source "fs/Kconfig"
2750 source "arch/x86/Kconfig.debug"
2752 source "security/Kconfig"
2754 source "crypto/Kconfig"
2756 source "arch/x86/kvm/Kconfig"
2758 source "lib/Kconfig"