| blob | e0055b4302d65aa02daf8be880b8d5b804360e83 |
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_ACPI_TABLE_UPGRADE if ACPI
26 select ARCH_HAS_DEVMEM_IS_ALLOWED
27 select ARCH_HAS_ELF_RANDOMIZE
28 select ARCH_HAS_FAST_MULTIPLIER
29 select ARCH_HAS_GCOV_PROFILE_ALL
30 select ARCH_HAS_GIGANTIC_PAGE if X86_64
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
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 BUILDTIME_EXTABLE_SORT
53 select CLKEVT_I8253
54 select CLKSRC_I8253 if X86_32
55 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
56 select CLOCKSOURCE_WATCHDOG
57 select CLONE_BACKWARDS if X86_32
58 select COMPAT_OLD_SIGACTION if IA32_EMULATION
59 select DCACHE_WORD_ACCESS
60 select EDAC_ATOMIC_SCRUB
61 select EDAC_SUPPORT
62 select GENERIC_CLOCKEVENTS
63 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
64 select GENERIC_CLOCKEVENTS_MIN_ADJUST
65 select GENERIC_CMOS_UPDATE
66 select GENERIC_CPU_AUTOPROBE
67 select GENERIC_CPU_VULNERABILITIES
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_HARDENED_USERCOPY
84 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
85 select HAVE_ARCH_JUMP_LABEL
86 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
87 select HAVE_ARCH_KGDB
88 select HAVE_ARCH_KMEMCHECK
89 select HAVE_ARCH_MMAP_RND_BITS if MMU
90 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
91 select HAVE_ARCH_SECCOMP_FILTER
92 select HAVE_ARCH_SOFT_DIRTY if X86_64
93 select HAVE_ARCH_TRACEHOOK
94 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
95 select HAVE_ARCH_WITHIN_STACK_FRAMES
96 select HAVE_EBPF_JIT if X86_64
97 select HAVE_ARCH_VMAP_STACK if X86_64
98 select HAVE_CC_STACKPROTECTOR
99 select HAVE_CMPXCHG_DOUBLE
100 select HAVE_CMPXCHG_LOCAL
101 select HAVE_CONTEXT_TRACKING if X86_64
102 select HAVE_COPY_THREAD_TLS
103 select HAVE_C_RECORDMCOUNT
104 select HAVE_DEBUG_KMEMLEAK
105 select HAVE_DEBUG_STACKOVERFLOW
106 select HAVE_DMA_API_DEBUG
107 select HAVE_DMA_CONTIGUOUS
108 select HAVE_DYNAMIC_FTRACE
109 select HAVE_DYNAMIC_FTRACE_WITH_REGS
110 select HAVE_EFFICIENT_UNALIGNED_ACCESS
111 select HAVE_EXIT_THREAD
112 select HAVE_FENTRY if X86_64
113 select HAVE_FTRACE_MCOUNT_RECORD
114 select HAVE_FUNCTION_GRAPH_TRACER
115 select HAVE_FUNCTION_TRACER
116 select HAVE_GCC_PLUGINS
117 select HAVE_GENERIC_DMA_COHERENT if X86_32
118 select HAVE_HW_BREAKPOINT
119 select HAVE_IDE
120 select HAVE_IOREMAP_PROT
121 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
122 select HAVE_IRQ_TIME_ACCOUNTING
123 select HAVE_KERNEL_BZIP2
124 select HAVE_KERNEL_GZIP
125 select HAVE_KERNEL_LZ4
126 select HAVE_KERNEL_LZMA
127 select HAVE_KERNEL_LZO
128 select HAVE_KERNEL_XZ
129 select HAVE_KPROBES
130 select HAVE_KPROBES_ON_FTRACE
131 select HAVE_KRETPROBES
132 select HAVE_KVM
133 select HAVE_LIVEPATCH if X86_64
134 select HAVE_MEMBLOCK
135 select HAVE_MEMBLOCK_NODE_MAP
136 select HAVE_MIXED_BREAKPOINTS_REGS
137 select HAVE_NMI
138 select HAVE_OPROFILE
139 select HAVE_OPTPROBES
140 select HAVE_PCSPKR_PLATFORM
141 select HAVE_PERF_EVENTS
142 select HAVE_PERF_EVENTS_NMI
143 select HAVE_PERF_REGS
144 select HAVE_PERF_USER_STACK_DUMP
145 select HAVE_REGS_AND_STACK_ACCESS_API
146 select HAVE_SYSCALL_TRACEPOINTS
147 select HAVE_UID16 if X86_32 || IA32_EMULATION
148 select HAVE_UNSTABLE_SCHED_CLOCK
149 select HAVE_USER_RETURN_NOTIFIER
150 select HOTPLUG_SMT if SMP
151 select IRQ_FORCED_THREADING
152 select MODULES_USE_ELF_RELA if X86_64
153 select MODULES_USE_ELF_REL if X86_32
154 select OLD_SIGACTION if X86_32
155 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
156 select PERF_EVENTS
157 select RTC_LIB
158 select RTC_MC146818_LIB
159 select SPARSE_IRQ
160 select SRCU
161 select SYSCTL_EXCEPTION_TRACE
162 select THREAD_INFO_IN_TASK
163 select USER_STACKTRACE_SUPPORT
164 select VIRT_TO_BUS
165 select X86_DEV_DMA_OPS if X86_64
166 select X86_FEATURE_NAMES if PROC_FS
167 select HAVE_STACK_VALIDATION if X86_64
168 select ARCH_USES_HIGH_VMA_FLAGS if X86_INTEL_MEMORY_PROTECTION_KEYS
169 select ARCH_HAS_PKEYS if X86_INTEL_MEMORY_PROTECTION_KEYS
171 config INSTRUCTION_DECODER
172 def_bool y
173 depends on KPROBES || PERF_EVENTS || UPROBES
175 config OUTPUT_FORMAT
176 string
177 default "elf32-i386" if X86_32
178 default "elf64-x86-64" if X86_64
180 config ARCH_DEFCONFIG
181 string
182 default "arch/x86/configs/i386_defconfig" if X86_32
183 default "arch/x86/configs/x86_64_defconfig" if X86_64
185 config LOCKDEP_SUPPORT
186 def_bool y
188 config STACKTRACE_SUPPORT
189 def_bool y
191 config MMU
192 def_bool y
194 config ARCH_MMAP_RND_BITS_MIN
195 default 28 if 64BIT
196 default 8
198 config ARCH_MMAP_RND_BITS_MAX
199 default 32 if 64BIT
200 default 16
202 config ARCH_MMAP_RND_COMPAT_BITS_MIN
203 default 8
205 config ARCH_MMAP_RND_COMPAT_BITS_MAX
206 default 16
208 config SBUS
209 bool
211 config NEED_DMA_MAP_STATE
212 def_bool y
213 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
215 config NEED_SG_DMA_LENGTH
216 def_bool y
218 config GENERIC_ISA_DMA
219 def_bool y
220 depends on ISA_DMA_API
222 config GENERIC_BUG
223 def_bool y
224 depends on BUG
225 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
227 config GENERIC_BUG_RELATIVE_POINTERS
228 bool
230 config GENERIC_HWEIGHT
231 def_bool y
233 config ARCH_MAY_HAVE_PC_FDC
234 def_bool y
235 depends on ISA_DMA_API
237 config RWSEM_XCHGADD_ALGORITHM
238 def_bool y
240 config GENERIC_CALIBRATE_DELAY
241 def_bool y
243 config ARCH_HAS_CPU_RELAX
244 def_bool y
246 config ARCH_HAS_CACHE_LINE_SIZE
247 def_bool y
249 config HAVE_SETUP_PER_CPU_AREA
250 def_bool y
252 config NEED_PER_CPU_EMBED_FIRST_CHUNK
253 def_bool y
255 config NEED_PER_CPU_PAGE_FIRST_CHUNK
256 def_bool y
258 config ARCH_HIBERNATION_POSSIBLE
259 def_bool y
261 config ARCH_SUSPEND_POSSIBLE
262 def_bool y
264 config ARCH_WANT_HUGE_PMD_SHARE
265 def_bool y
267 config ARCH_WANT_GENERAL_HUGETLB
268 def_bool y
270 config ZONE_DMA32
271 def_bool y if X86_64
273 config AUDIT_ARCH
274 def_bool y if X86_64
276 config ARCH_SUPPORTS_OPTIMIZED_INLINING
277 def_bool y
279 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
280 def_bool y
282 config KASAN_SHADOW_OFFSET
283 hex
284 depends on KASAN
285 default 0xdffffc0000000000
287 config HAVE_INTEL_TXT
288 def_bool y
289 depends on INTEL_IOMMU && ACPI
291 config X86_32_SMP
292 def_bool y
293 depends on X86_32 && SMP
295 config X86_64_SMP
296 def_bool y
297 depends on X86_64 && SMP
299 config X86_32_LAZY_GS
300 def_bool y
301 depends on X86_32 && !CC_STACKPROTECTOR
303 config ARCH_SUPPORTS_UPROBES
304 def_bool y
306 config FIX_EARLYCON_MEM
307 def_bool y
309 config DEBUG_RODATA
310 def_bool y
312 config PGTABLE_LEVELS
313 int
314 default 4 if X86_64
315 default 3 if X86_PAE
316 default 2
318 source "init/Kconfig"
319 source "kernel/Kconfig.freezer"
321 menu "Processor type and features"
323 config ZONE_DMA
324 bool "DMA memory allocation support" if EXPERT
325 default y
326 help
327 DMA memory allocation support allows devices with less than 32-bit
328 addressing to allocate within the first 16MB of address space.
329 Disable if no such devices will be used.
331 If unsure, say Y.
333 config SMP
334 bool "Symmetric multi-processing support"
335 ---help---
336 This enables support for systems with more than one CPU. If you have
337 a system with only one CPU, say N. If you have a system with more
338 than one CPU, say Y.
340 If you say N here, the kernel will run on uni- and multiprocessor
341 machines, but will use only one CPU of a multiprocessor machine. If
342 you say Y here, the kernel will run on many, but not all,
343 uniprocessor machines. On a uniprocessor machine, the kernel
344 will run faster if you say N here.
346 Note that if you say Y here and choose architecture "586" or
347 "Pentium" under "Processor family", the kernel will not work on 486
348 architectures. Similarly, multiprocessor kernels for the "PPro"
349 architecture may not work on all Pentium based boards.
351 People using multiprocessor machines who say Y here should also say
352 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
353 Management" code will be disabled if you say Y here.
355 See also <file:Documentation/x86/i386/IO-APIC.txt>,
356 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
357 <http://www.tldp.org/docs.html#howto>.
359 If you don't know what to do here, say N.
361 config X86_FEATURE_NAMES
362 bool "Processor feature human-readable names" if EMBEDDED
363 default y
364 ---help---
365 This option compiles in a table of x86 feature bits and corresponding
366 names. This is required to support /proc/cpuinfo and a few kernel
367 messages. You can disable this to save space, at the expense of
368 making those few kernel messages show numeric feature bits instead.
370 If in doubt, say Y.
372 config X86_FAST_FEATURE_TESTS
373 bool "Fast CPU feature tests" if EMBEDDED
374 default y
375 ---help---
376 Some fast-paths in the kernel depend on the capabilities of the CPU.
377 Say Y here for the kernel to patch in the appropriate code at runtime
378 based on the capabilities of the CPU. The infrastructure for patching
379 code at runtime takes up some additional space; space-constrained
380 embedded systems may wish to say N here to produce smaller, slightly
381 slower code.
383 config X86_X2APIC
384 bool "Support x2apic"
385 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
386 ---help---
387 This enables x2apic support on CPUs that have this feature.
389 This allows 32-bit apic IDs (so it can support very large systems),
390 and accesses the local apic via MSRs not via mmio.
392 If you don't know what to do here, say N.
394 config X86_MPPARSE
395 bool "Enable MPS table" if ACPI || SFI
396 default y
397 depends on X86_LOCAL_APIC
398 ---help---
399 For old smp systems that do not have proper acpi support. Newer systems
400 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
402 config X86_BIGSMP
403 bool "Support for big SMP systems with more than 8 CPUs"
404 depends on X86_32 && SMP
405 ---help---
406 This option is needed for the systems that have more than 8 CPUs
408 config GOLDFISH
409 def_bool y
410 depends on X86_GOLDFISH
412 config RETPOLINE
413 bool "Avoid speculative indirect branches in kernel"
414 default y
415 ---help---
416 Compile kernel with the retpoline compiler options to guard against
417 kernel-to-user data leaks by avoiding speculative indirect
418 branches. Requires a compiler with -mindirect-branch=thunk-extern
419 support for full protection. The kernel may run slower.
421 Without compiler support, at least indirect branches in assembler
422 code are eliminated. Since this includes the syscall entry path,
423 it is not entirely pointless.
425 if X86_32
426 config X86_EXTENDED_PLATFORM
427 bool "Support for extended (non-PC) x86 platforms"
428 default y
429 ---help---
430 If you disable this option then the kernel will only support
431 standard PC platforms. (which covers the vast majority of
432 systems out there.)
434 If you enable this option then you'll be able to select support
435 for the following (non-PC) 32 bit x86 platforms:
436 Goldfish (Android emulator)
437 AMD Elan
438 RDC R-321x SoC
439 SGI 320/540 (Visual Workstation)
440 STA2X11-based (e.g. Northville)
441 Moorestown MID devices
443 If you have one of these systems, or if you want to build a
444 generic distribution kernel, say Y here - otherwise say N.
445 endif
447 if X86_64
448 config X86_EXTENDED_PLATFORM
449 bool "Support for extended (non-PC) x86 platforms"
450 default y
451 ---help---
452 If you disable this option then the kernel will only support
453 standard PC platforms. (which covers the vast majority of
454 systems out there.)
456 If you enable this option then you'll be able to select support
457 for the following (non-PC) 64 bit x86 platforms:
458 Numascale NumaChip
459 ScaleMP vSMP
460 SGI Ultraviolet
462 If you have one of these systems, or if you want to build a
463 generic distribution kernel, say Y here - otherwise say N.
464 endif
465 # This is an alphabetically sorted list of 64 bit extended platforms
466 # Please maintain the alphabetic order if and when there are additions
467 config X86_NUMACHIP
468 bool "Numascale NumaChip"
469 depends on X86_64
470 depends on X86_EXTENDED_PLATFORM
471 depends on NUMA
472 depends on SMP
473 depends on X86_X2APIC
474 depends on PCI_MMCONFIG
475 ---help---
476 Adds support for Numascale NumaChip large-SMP systems. Needed to
477 enable more than ~168 cores.
478 If you don't have one of these, you should say N here.
480 config X86_VSMP
481 bool "ScaleMP vSMP"
482 select HYPERVISOR_GUEST
483 select PARAVIRT
484 depends on X86_64 && PCI
485 depends on X86_EXTENDED_PLATFORM
486 depends on SMP
487 ---help---
488 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
489 supposed to run on these EM64T-based machines. Only choose this option
490 if you have one of these machines.
492 config X86_UV
493 bool "SGI Ultraviolet"
494 depends on X86_64
495 depends on X86_EXTENDED_PLATFORM
496 depends on NUMA
497 depends on EFI
498 depends on X86_X2APIC
499 depends on PCI
500 ---help---
501 This option is needed in order to support SGI Ultraviolet systems.
502 If you don't have one of these, you should say N here.
504 # Following is an alphabetically sorted list of 32 bit extended platforms
505 # Please maintain the alphabetic order if and when there are additions
507 config X86_GOLDFISH
508 bool "Goldfish (Virtual Platform)"
509 depends on X86_EXTENDED_PLATFORM
510 ---help---
511 Enable support for the Goldfish virtual platform used primarily
512 for Android development. Unless you are building for the Android
513 Goldfish emulator say N here.
515 config X86_INTEL_CE
516 bool "CE4100 TV platform"
517 depends on PCI
518 depends on PCI_GODIRECT
519 depends on X86_IO_APIC
520 depends on X86_32
521 depends on X86_EXTENDED_PLATFORM
522 select X86_REBOOTFIXUPS
523 select OF
524 select OF_EARLY_FLATTREE
525 ---help---
526 Select for the Intel CE media processor (CE4100) SOC.
527 This option compiles in support for the CE4100 SOC for settop
528 boxes and media devices.
530 config X86_INTEL_MID
531 bool "Intel MID platform support"
532 depends on X86_EXTENDED_PLATFORM
533 depends on X86_PLATFORM_DEVICES
534 depends on PCI
535 depends on X86_64 || (PCI_GOANY && X86_32)
536 depends on X86_IO_APIC
537 select SFI
538 select I2C
539 select DW_APB_TIMER
540 select APB_TIMER
541 select INTEL_SCU_IPC
542 select MFD_INTEL_MSIC
543 ---help---
544 Select to build a kernel capable of supporting Intel MID (Mobile
545 Internet Device) platform systems which do not have the PCI legacy
546 interfaces. If you are building for a PC class system say N here.
548 Intel MID platforms are based on an Intel processor and chipset which
549 consume less power than most of the x86 derivatives.
551 config X86_INTEL_QUARK
552 bool "Intel Quark platform support"
553 depends on X86_32
554 depends on X86_EXTENDED_PLATFORM
555 depends on X86_PLATFORM_DEVICES
556 depends on X86_TSC
557 depends on PCI
558 depends on PCI_GOANY
559 depends on X86_IO_APIC
560 select IOSF_MBI
561 select INTEL_IMR
562 select COMMON_CLK
563 ---help---
564 Select to include support for Quark X1000 SoC.
565 Say Y here if you have a Quark based system such as the Arduino
566 compatible Intel Galileo.
568 config MLX_PLATFORM
569 tristate "Mellanox Technologies platform support"
570 depends on X86_64
571 depends on X86_EXTENDED_PLATFORM
572 ---help---
573 This option enables system support for the Mellanox Technologies
574 platform.
576 Say Y here if you are building a kernel for Mellanox system.
578 Otherwise, say N.
580 config X86_INTEL_LPSS
581 bool "Intel Low Power Subsystem Support"
582 depends on X86 && ACPI
583 select COMMON_CLK
584 select PINCTRL
585 select IOSF_MBI
586 ---help---
587 Select to build support for Intel Low Power Subsystem such as
588 found on Intel Lynxpoint PCH. Selecting this option enables
589 things like clock tree (common clock framework) and pincontrol
590 which are needed by the LPSS peripheral drivers.
592 config X86_AMD_PLATFORM_DEVICE
593 bool "AMD ACPI2Platform devices support"
594 depends on ACPI
595 select COMMON_CLK
596 select PINCTRL
597 ---help---
598 Select to interpret AMD specific ACPI device to platform device
599 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
600 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
601 implemented under PINCTRL subsystem.
603 config IOSF_MBI
604 tristate "Intel SoC IOSF Sideband support for SoC platforms"
605 depends on PCI
606 ---help---
607 This option enables sideband register access support for Intel SoC
608 platforms. On these platforms the IOSF sideband is used in lieu of
609 MSR's for some register accesses, mostly but not limited to thermal
610 and power. Drivers may query the availability of this device to
611 determine if they need the sideband in order to work on these
612 platforms. The sideband is available on the following SoC products.
613 This list is not meant to be exclusive.
614 - BayTrail
615 - Braswell
616 - Quark
618 You should say Y if you are running a kernel on one of these SoC's.
620 config IOSF_MBI_DEBUG
621 bool "Enable IOSF sideband access through debugfs"
622 depends on IOSF_MBI && DEBUG_FS
623 ---help---
624 Select this option to expose the IOSF sideband access registers (MCR,
625 MDR, MCRX) through debugfs to write and read register information from
626 different units on the SoC. This is most useful for obtaining device
627 state information for debug and analysis. As this is a general access
628 mechanism, users of this option would have specific knowledge of the
629 device they want to access.
631 If you don't require the option or are in doubt, say N.
633 config X86_RDC321X
634 bool "RDC R-321x SoC"
635 depends on X86_32
636 depends on X86_EXTENDED_PLATFORM
637 select M486
638 select X86_REBOOTFIXUPS
639 ---help---
640 This option is needed for RDC R-321x system-on-chip, also known
641 as R-8610-(G).
642 If you don't have one of these chips, you should say N here.
644 config X86_32_NON_STANDARD
645 bool "Support non-standard 32-bit SMP architectures"
646 depends on X86_32 && SMP
647 depends on X86_EXTENDED_PLATFORM
648 ---help---
649 This option compiles in the bigsmp and STA2X11 default
650 subarchitectures. It is intended for a generic binary
651 kernel. If you select them all, kernel will probe it one by
652 one and will fallback to default.
654 # Alphabetically sorted list of Non standard 32 bit platforms
656 config X86_SUPPORTS_MEMORY_FAILURE
657 def_bool y
658 # MCE code calls memory_failure():
659 depends on X86_MCE
660 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
661 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
662 depends on X86_64 || !SPARSEMEM
663 select ARCH_SUPPORTS_MEMORY_FAILURE
665 config STA2X11
666 bool "STA2X11 Companion Chip Support"
667 depends on X86_32_NON_STANDARD && PCI
668 select X86_DEV_DMA_OPS
669 select X86_DMA_REMAP
670 select SWIOTLB
671 select MFD_STA2X11
672 select GPIOLIB
673 default n
674 ---help---
675 This adds support for boards based on the STA2X11 IO-Hub,
676 a.k.a. "ConneXt". The chip is used in place of the standard
677 PC chipset, so all "standard" peripherals are missing. If this
678 option is selected the kernel will still be able to boot on
679 standard PC machines.
681 config X86_32_IRIS
682 tristate "Eurobraille/Iris poweroff module"
683 depends on X86_32
684 ---help---
685 The Iris machines from EuroBraille do not have APM or ACPI support
686 to shut themselves down properly. A special I/O sequence is
687 needed to do so, which is what this module does at
688 kernel shutdown.
690 This is only for Iris machines from EuroBraille.
692 If unused, say N.
694 config SCHED_OMIT_FRAME_POINTER
695 def_bool y
696 prompt "Single-depth WCHAN output"
697 depends on X86
698 ---help---
699 Calculate simpler /proc/<PID>/wchan values. If this option
700 is disabled then wchan values will recurse back to the
701 caller function. This provides more accurate wchan values,
702 at the expense of slightly more scheduling overhead.
704 If in doubt, say "Y".
706 menuconfig HYPERVISOR_GUEST
707 bool "Linux guest support"
708 ---help---
709 Say Y here to enable options for running Linux under various hyper-
710 visors. This option enables basic hypervisor detection and platform
711 setup.
713 If you say N, all options in this submenu will be skipped and
714 disabled, and Linux guest support won't be built in.
716 if HYPERVISOR_GUEST
718 config PARAVIRT
719 bool "Enable paravirtualization code"
720 ---help---
721 This changes the kernel so it can modify itself when it is run
722 under a hypervisor, potentially improving performance significantly
723 over full virtualization. However, when run without a hypervisor
724 the kernel is theoretically slower and slightly larger.
726 config PARAVIRT_DEBUG
727 bool "paravirt-ops debugging"
728 depends on PARAVIRT && DEBUG_KERNEL
729 ---help---
730 Enable to debug paravirt_ops internals. Specifically, BUG if
731 a paravirt_op is missing when it is called.
733 config PARAVIRT_SPINLOCKS
734 bool "Paravirtualization layer for spinlocks"
735 depends on PARAVIRT && SMP
736 ---help---
737 Paravirtualized spinlocks allow a pvops backend to replace the
738 spinlock implementation with something virtualization-friendly
739 (for example, block the virtual CPU rather than spinning).
741 It has a minimal impact on native kernels and gives a nice performance
742 benefit on paravirtualized KVM / Xen kernels.
744 If you are unsure how to answer this question, answer Y.
746 config QUEUED_LOCK_STAT
747 bool "Paravirt queued spinlock statistics"
748 depends on PARAVIRT_SPINLOCKS && DEBUG_FS
749 ---help---
750 Enable the collection of statistical data on the slowpath
751 behavior of paravirtualized queued spinlocks and report
752 them on debugfs.
754 source "arch/x86/xen/Kconfig"
756 config KVM_GUEST
757 bool "KVM Guest support (including kvmclock)"
758 depends on PARAVIRT
759 select PARAVIRT_CLOCK
760 default y
761 ---help---
762 This option enables various optimizations for running under the KVM
763 hypervisor. It includes a paravirtualized clock, so that instead
764 of relying on a PIT (or probably other) emulation by the
765 underlying device model, the host provides the guest with
766 timing infrastructure such as time of day, and system time
768 config KVM_DEBUG_FS
769 bool "Enable debug information for KVM Guests in debugfs"
770 depends on KVM_GUEST && DEBUG_FS
771 default n
772 ---help---
773 This option enables collection of various statistics for KVM guest.
774 Statistics are displayed in debugfs filesystem. Enabling this option
775 may incur significant overhead.
777 source "arch/x86/lguest/Kconfig"
779 config PARAVIRT_TIME_ACCOUNTING
780 bool "Paravirtual steal time accounting"
781 depends on PARAVIRT
782 default n
783 ---help---
784 Select this option to enable fine granularity task steal time
785 accounting. Time spent executing other tasks in parallel with
786 the current vCPU is discounted from the vCPU power. To account for
787 that, there can be a small performance impact.
789 If in doubt, say N here.
791 config PARAVIRT_CLOCK
792 bool
794 endif #HYPERVISOR_GUEST
796 config NO_BOOTMEM
797 def_bool y
799 source "arch/x86/Kconfig.cpu"
801 config HPET_TIMER
802 def_bool X86_64
803 prompt "HPET Timer Support" if X86_32
804 ---help---
805 Use the IA-PC HPET (High Precision Event Timer) to manage
806 time in preference to the PIT and RTC, if a HPET is
807 present.
808 HPET is the next generation timer replacing legacy 8254s.
809 The HPET provides a stable time base on SMP
810 systems, unlike the TSC, but it is more expensive to access,
811 as it is off-chip. The interface used is documented
812 in the HPET spec, revision 1.
814 You can safely choose Y here. However, HPET will only be
815 activated if the platform and the BIOS support this feature.
816 Otherwise the 8254 will be used for timing services.
818 Choose N to continue using the legacy 8254 timer.
820 config HPET_EMULATE_RTC
821 def_bool y
822 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
824 config APB_TIMER
825 def_bool y if X86_INTEL_MID
826 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
827 select DW_APB_TIMER
828 depends on X86_INTEL_MID && SFI
829 help
830 APB timer is the replacement for 8254, HPET on X86 MID platforms.
831 The APBT provides a stable time base on SMP
832 systems, unlike the TSC, but it is more expensive to access,
833 as it is off-chip. APB timers are always running regardless of CPU
834 C states, they are used as per CPU clockevent device when possible.
836 # Mark as expert because too many people got it wrong.
837 # The code disables itself when not needed.
838 config DMI
839 default y
840 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
841 bool "Enable DMI scanning" if EXPERT
842 ---help---
843 Enabled scanning of DMI to identify machine quirks. Say Y
844 here unless you have verified that your setup is not
845 affected by entries in the DMI blacklist. Required by PNP
846 BIOS code.
848 config GART_IOMMU
849 bool "Old AMD GART IOMMU support"
850 select SWIOTLB
851 depends on X86_64 && PCI && AMD_NB
852 ---help---
853 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
854 GART based hardware IOMMUs.
856 The GART supports full DMA access for devices with 32-bit access
857 limitations, on systems with more than 3 GB. This is usually needed
858 for USB, sound, many IDE/SATA chipsets and some other devices.
860 Newer systems typically have a modern AMD IOMMU, supported via
861 the CONFIG_AMD_IOMMU=y config option.
863 In normal configurations this driver is only active when needed:
864 there's more than 3 GB of memory and the system contains a
865 32-bit limited device.
867 If unsure, say Y.
869 config CALGARY_IOMMU
870 bool "IBM Calgary IOMMU support"
871 select SWIOTLB
872 depends on X86_64 && PCI
873 ---help---
874 Support for hardware IOMMUs in IBM's xSeries x366 and x460
875 systems. Needed to run systems with more than 3GB of memory
876 properly with 32-bit PCI devices that do not support DAC
877 (Double Address Cycle). Calgary also supports bus level
878 isolation, where all DMAs pass through the IOMMU. This
879 prevents them from going anywhere except their intended
880 destination. This catches hard-to-find kernel bugs and
881 mis-behaving drivers and devices that do not use the DMA-API
882 properly to set up their DMA buffers. The IOMMU can be
883 turned off at boot time with the iommu=off parameter.
884 Normally the kernel will make the right choice by itself.
885 If unsure, say Y.
887 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
888 def_bool y
889 prompt "Should Calgary be enabled by default?"
890 depends on CALGARY_IOMMU
891 ---help---
892 Should Calgary be enabled by default? if you choose 'y', Calgary
893 will be used (if it exists). If you choose 'n', Calgary will not be
894 used even if it exists. If you choose 'n' and would like to use
895 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
896 If unsure, say Y.
898 # need this always selected by IOMMU for the VIA workaround
899 config SWIOTLB
900 def_bool y if X86_64
901 ---help---
902 Support for software bounce buffers used on x86-64 systems
903 which don't have a hardware IOMMU. Using this PCI devices
904 which can only access 32-bits of memory can be used on systems
905 with more than 3 GB of memory.
906 If unsure, say Y.
908 config IOMMU_HELPER
909 def_bool y
910 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
912 config MAXSMP
913 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
914 depends on X86_64 && SMP && DEBUG_KERNEL
915 select CPUMASK_OFFSTACK
916 ---help---
917 Enable maximum number of CPUS and NUMA Nodes for this architecture.
918 If unsure, say N.
920 config NR_CPUS
921 int "Maximum number of CPUs" if SMP && !MAXSMP
922 range 2 8 if SMP && X86_32 && !X86_BIGSMP
923 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
924 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
925 default "1" if !SMP
926 default "8192" if MAXSMP
927 default "32" if SMP && X86_BIGSMP
928 default "8" if SMP && X86_32
929 default "64" if SMP
930 ---help---
931 This allows you to specify the maximum number of CPUs which this
932 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
933 supported value is 8192, otherwise the maximum value is 512. The
934 minimum value which makes sense is 2.
936 This is purely to save memory - each supported CPU adds
937 approximately eight kilobytes to the kernel image.
939 config SCHED_SMT
940 def_bool y if SMP
942 config SCHED_MC
943 def_bool y
944 prompt "Multi-core scheduler support"
945 depends on SMP
946 ---help---
947 Multi-core scheduler support improves the CPU scheduler's decision
948 making when dealing with multi-core CPU chips at a cost of slightly
949 increased overhead in some places. If unsure say N here.
951 source "kernel/Kconfig.preempt"
953 config UP_LATE_INIT
954 def_bool y
955 depends on !SMP && X86_LOCAL_APIC
957 config X86_UP_APIC
958 bool "Local APIC support on uniprocessors" if !PCI_MSI
959 default PCI_MSI
960 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
961 ---help---
962 A local APIC (Advanced Programmable Interrupt Controller) is an
963 integrated interrupt controller in the CPU. If you have a single-CPU
964 system which has a processor with a local APIC, you can say Y here to
965 enable and use it. If you say Y here even though your machine doesn't
966 have a local APIC, then the kernel will still run with no slowdown at
967 all. The local APIC supports CPU-generated self-interrupts (timer,
968 performance counters), and the NMI watchdog which detects hard
969 lockups.
971 config X86_UP_IOAPIC
972 bool "IO-APIC support on uniprocessors"
973 depends on X86_UP_APIC
974 ---help---
975 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
976 SMP-capable replacement for PC-style interrupt controllers. Most
977 SMP systems and many recent uniprocessor systems have one.
979 If you have a single-CPU system with an IO-APIC, you can say Y here
980 to use it. If you say Y here even though your machine doesn't have
981 an IO-APIC, then the kernel will still run with no slowdown at all.
983 config X86_LOCAL_APIC
984 def_bool y
985 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
986 select IRQ_DOMAIN_HIERARCHY
987 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
989 config X86_IO_APIC
990 def_bool y
991 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
993 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
994 bool "Reroute for broken boot IRQs"
995 depends on X86_IO_APIC
996 ---help---
997 This option enables a workaround that fixes a source of
998 spurious interrupts. This is recommended when threaded
999 interrupt handling is used on systems where the generation of
1000 superfluous "boot interrupts" cannot be disabled.
1002 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
1003 entry in the chipset's IO-APIC is masked (as, e.g. the RT
1004 kernel does during interrupt handling). On chipsets where this
1005 boot IRQ generation cannot be disabled, this workaround keeps
1006 the original IRQ line masked so that only the equivalent "boot
1007 IRQ" is delivered to the CPUs. The workaround also tells the
1008 kernel to set up the IRQ handler on the boot IRQ line. In this
1009 way only one interrupt is delivered to the kernel. Otherwise
1010 the spurious second interrupt may cause the kernel to bring
1011 down (vital) interrupt lines.
1013 Only affects "broken" chipsets. Interrupt sharing may be
1014 increased on these systems.
1016 config X86_MCE
1017 bool "Machine Check / overheating reporting"
1018 select GENERIC_ALLOCATOR
1019 default y
1020 ---help---
1021 Machine Check support allows the processor to notify the
1022 kernel if it detects a problem (e.g. overheating, data corruption).
1023 The action the kernel takes depends on the severity of the problem,
1024 ranging from warning messages to halting the machine.
1026 config X86_MCE_INTEL
1027 def_bool y
1028 prompt "Intel MCE features"
1029 depends on X86_MCE && X86_LOCAL_APIC
1030 ---help---
1031 Additional support for intel specific MCE features such as
1032 the thermal monitor.
1034 config X86_MCE_AMD
1035 def_bool y
1036 prompt "AMD MCE features"
1037 depends on X86_MCE && X86_LOCAL_APIC
1038 ---help---
1039 Additional support for AMD specific MCE features such as
1040 the DRAM Error Threshold.
1042 config X86_ANCIENT_MCE
1043 bool "Support for old Pentium 5 / WinChip machine checks"
1044 depends on X86_32 && X86_MCE
1045 ---help---
1046 Include support for machine check handling on old Pentium 5 or WinChip
1047 systems. These typically need to be enabled explicitly on the command
1048 line.
1050 config X86_MCE_THRESHOLD
1051 depends on X86_MCE_AMD || X86_MCE_INTEL
1052 def_bool y
1054 config X86_MCE_INJECT
1055 depends on X86_MCE && X86_LOCAL_APIC
1056 tristate "Machine check injector support"
1057 ---help---
1058 Provide support for injecting machine checks for testing purposes.
1059 If you don't know what a machine check is and you don't do kernel
1060 QA it is safe to say n.
1062 config X86_THERMAL_VECTOR
1063 def_bool y
1064 depends on X86_MCE_INTEL
1066 source "arch/x86/events/Kconfig"
1068 config X86_LEGACY_VM86
1069 bool "Legacy VM86 support"
1070 default n
1071 depends on X86_32
1072 ---help---
1073 This option allows user programs to put the CPU into V8086
1074 mode, which is an 80286-era approximation of 16-bit real mode.
1076 Some very old versions of X and/or vbetool require this option
1077 for user mode setting. Similarly, DOSEMU will use it if
1078 available to accelerate real mode DOS programs. However, any
1079 recent version of DOSEMU, X, or vbetool should be fully
1080 functional even without kernel VM86 support, as they will all
1081 fall back to software emulation. Nevertheless, if you are using
1082 a 16-bit DOS program where 16-bit performance matters, vm86
1083 mode might be faster than emulation and you might want to
1084 enable this option.
1086 Note that any app that works on a 64-bit kernel is unlikely to
1087 need this option, as 64-bit kernels don't, and can't, support
1088 V8086 mode. This option is also unrelated to 16-bit protected
1089 mode and is not needed to run most 16-bit programs under Wine.
1091 Enabling this option increases the complexity of the kernel
1092 and slows down exception handling a tiny bit.
1094 If unsure, say N here.
1096 config VM86
1097 bool
1098 default X86_LEGACY_VM86
1100 config X86_16BIT
1101 bool "Enable support for 16-bit segments" if EXPERT
1102 default y
1103 depends on MODIFY_LDT_SYSCALL
1104 ---help---
1105 This option is required by programs like Wine to run 16-bit
1106 protected mode legacy code on x86 processors. Disabling
1107 this option saves about 300 bytes on i386, or around 6K text
1108 plus 16K runtime memory on x86-64,
1110 config X86_ESPFIX32
1111 def_bool y
1112 depends on X86_16BIT && X86_32
1114 config X86_ESPFIX64
1115 def_bool y
1116 depends on X86_16BIT && X86_64
1118 config X86_VSYSCALL_EMULATION
1119 bool "Enable vsyscall emulation" if EXPERT
1120 default y
1121 depends on X86_64
1122 ---help---
1123 This enables emulation of the legacy vsyscall page. Disabling
1124 it is roughly equivalent to booting with vsyscall=none, except
1125 that it will also disable the helpful warning if a program
1126 tries to use a vsyscall. With this option set to N, offending
1127 programs will just segfault, citing addresses of the form
1128 0xffffffffff600?00.
1130 This option is required by many programs built before 2013, and
1131 care should be used even with newer programs if set to N.
1133 Disabling this option saves about 7K of kernel size and
1134 possibly 4K of additional runtime pagetable memory.
1136 config TOSHIBA
1137 tristate "Toshiba Laptop support"
1138 depends on X86_32
1139 ---help---
1140 This adds a driver to safely access the System Management Mode of
1141 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1142 not work on models with a Phoenix BIOS. The System Management Mode
1143 is used to set the BIOS and power saving options on Toshiba portables.
1145 For information on utilities to make use of this driver see the
1146 Toshiba Linux utilities web site at:
1147 <http://www.buzzard.org.uk/toshiba/>.
1149 Say Y if you intend to run this kernel on a Toshiba portable.
1150 Say N otherwise.
1152 config I8K
1153 tristate "Dell i8k legacy laptop support"
1154 select HWMON
1155 select SENSORS_DELL_SMM
1156 ---help---
1157 This option enables legacy /proc/i8k userspace interface in hwmon
1158 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1159 temperature and allows controlling fan speeds of Dell laptops via
1160 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1161 it reports also power and hotkey status. For fan speed control is
1162 needed userspace package i8kutils.
1164 Say Y if you intend to run this kernel on old Dell laptops or want to
1165 use userspace package i8kutils.
1166 Say N otherwise.
1168 config X86_REBOOTFIXUPS
1169 bool "Enable X86 board specific fixups for reboot"
1170 depends on X86_32
1171 ---help---
1172 This enables chipset and/or board specific fixups to be done
1173 in order to get reboot to work correctly. This is only needed on
1174 some combinations of hardware and BIOS. The symptom, for which
1175 this config is intended, is when reboot ends with a stalled/hung
1176 system.
1178 Currently, the only fixup is for the Geode machines using
1179 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1181 Say Y if you want to enable the fixup. Currently, it's safe to
1182 enable this option even if you don't need it.
1183 Say N otherwise.
1185 config MICROCODE
1186 bool "CPU microcode loading support"
1187 default y
1188 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1189 select FW_LOADER
1190 ---help---
1191 If you say Y here, you will be able to update the microcode on
1192 Intel and AMD processors. The Intel support is for the IA32 family,
1193 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
1194 AMD support is for families 0x10 and later. You will obviously need
1195 the actual microcode binary data itself which is not shipped with
1196 the Linux kernel.
1198 The preferred method to load microcode from a detached initrd is described
1199 in Documentation/x86/early-microcode.txt. For that you need to enable
1200 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
1201 initrd for microcode blobs.
1203 In addition, you can build-in the microcode into the kernel. For that you
1204 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode
1205 to the CONFIG_EXTRA_FIRMWARE config option.
1207 config MICROCODE_INTEL
1208 bool "Intel microcode loading support"
1209 depends on MICROCODE
1210 default MICROCODE
1211 select FW_LOADER
1212 ---help---
1213 This options enables microcode patch loading support for Intel
1214 processors.
1216 For the current Intel microcode data package go to
1217 <https://downloadcenter.intel.com> and search for
1218 'Linux Processor Microcode Data File'.
1220 config MICROCODE_AMD
1221 bool "AMD microcode loading support"
1222 depends on MICROCODE
1223 select FW_LOADER
1224 ---help---
1225 If you select this option, microcode patch loading support for AMD
1226 processors will be enabled.
1228 config MICROCODE_OLD_INTERFACE
1229 def_bool y
1230 depends on MICROCODE
1232 config X86_MSR
1233 tristate "/dev/cpu/*/msr - Model-specific register support"
1234 ---help---
1235 This device gives privileged processes access to the x86
1236 Model-Specific Registers (MSRs). It is a character device with
1237 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1238 MSR accesses are directed to a specific CPU on multi-processor
1239 systems.
1241 config X86_CPUID
1242 tristate "/dev/cpu/*/cpuid - CPU information support"
1243 ---help---
1244 This device gives processes access to the x86 CPUID instruction to
1245 be executed on a specific processor. It is a character device
1246 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1247 /dev/cpu/31/cpuid.
1249 choice
1250 prompt "High Memory Support"
1251 default HIGHMEM4G
1252 depends on X86_32
1254 config NOHIGHMEM
1255 bool "off"
1256 ---help---
1257 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1258 However, the address space of 32-bit x86 processors is only 4
1259 Gigabytes large. That means that, if you have a large amount of
1260 physical memory, not all of it can be "permanently mapped" by the
1261 kernel. The physical memory that's not permanently mapped is called
1262 "high memory".
1264 If you are compiling a kernel which will never run on a machine with
1265 more than 1 Gigabyte total physical RAM, answer "off" here (default
1266 choice and suitable for most users). This will result in a "3GB/1GB"
1267 split: 3GB are mapped so that each process sees a 3GB virtual memory
1268 space and the remaining part of the 4GB virtual memory space is used
1269 by the kernel to permanently map as much physical memory as
1270 possible.
1272 If the machine has between 1 and 4 Gigabytes physical RAM, then
1273 answer "4GB" here.
1275 If more than 4 Gigabytes is used then answer "64GB" here. This
1276 selection turns Intel PAE (Physical Address Extension) mode on.
1277 PAE implements 3-level paging on IA32 processors. PAE is fully
1278 supported by Linux, PAE mode is implemented on all recent Intel
1279 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1280 then the kernel will not boot on CPUs that don't support PAE!
1282 The actual amount of total physical memory will either be
1283 auto detected or can be forced by using a kernel command line option
1284 such as "mem=256M". (Try "man bootparam" or see the documentation of
1285 your boot loader (lilo or loadlin) about how to pass options to the
1286 kernel at boot time.)
1288 If unsure, say "off".
1290 config HIGHMEM4G
1291 bool "4GB"
1292 ---help---
1293 Select this if you have a 32-bit processor and between 1 and 4
1294 gigabytes of physical RAM.
1296 config HIGHMEM64G
1297 bool "64GB"
1298 depends on !M486
1299 select X86_PAE
1300 ---help---
1301 Select this if you have a 32-bit processor and more than 4
1302 gigabytes of physical RAM.
1304 endchoice
1306 choice
1307 prompt "Memory split" if EXPERT
1308 default VMSPLIT_3G
1309 depends on X86_32
1310 ---help---
1311 Select the desired split between kernel and user memory.
1313 If the address range available to the kernel is less than the
1314 physical memory installed, the remaining memory will be available
1315 as "high memory". Accessing high memory is a little more costly
1316 than low memory, as it needs to be mapped into the kernel first.
1317 Note that increasing the kernel address space limits the range
1318 available to user programs, making the address space there
1319 tighter. Selecting anything other than the default 3G/1G split
1320 will also likely make your kernel incompatible with binary-only
1321 kernel modules.
1323 If you are not absolutely sure what you are doing, leave this
1324 option alone!
1326 config VMSPLIT_3G
1327 bool "3G/1G user/kernel split"
1328 config VMSPLIT_3G_OPT
1329 depends on !X86_PAE
1330 bool "3G/1G user/kernel split (for full 1G low memory)"
1331 config VMSPLIT_2G
1332 bool "2G/2G user/kernel split"
1333 config VMSPLIT_2G_OPT
1334 depends on !X86_PAE
1335 bool "2G/2G user/kernel split (for full 2G low memory)"
1336 config VMSPLIT_1G
1337 bool "1G/3G user/kernel split"
1338 endchoice
1340 config PAGE_OFFSET
1341 hex
1342 default 0xB0000000 if VMSPLIT_3G_OPT
1343 default 0x80000000 if VMSPLIT_2G
1344 default 0x78000000 if VMSPLIT_2G_OPT
1345 default 0x40000000 if VMSPLIT_1G
1346 default 0xC0000000
1347 depends on X86_32
1349 config HIGHMEM
1350 def_bool y
1351 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1353 config X86_PAE
1354 bool "PAE (Physical Address Extension) Support"
1355 depends on X86_32 && !HIGHMEM4G
1356 select SWIOTLB
1357 ---help---
1358 PAE is required for NX support, and furthermore enables
1359 larger swapspace support for non-overcommit purposes. It
1360 has the cost of more pagetable lookup overhead, and also
1361 consumes more pagetable space per process.
1363 config ARCH_PHYS_ADDR_T_64BIT
1364 def_bool y
1365 depends on X86_64 || X86_PAE
1367 config ARCH_DMA_ADDR_T_64BIT
1368 def_bool y
1369 depends on X86_64 || HIGHMEM64G
1371 config X86_DIRECT_GBPAGES
1372 def_bool y
1373 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1374 ---help---
1375 Certain kernel features effectively disable kernel
1376 linear 1 GB mappings (even if the CPU otherwise
1377 supports them), so don't confuse the user by printing
1378 that we have them enabled.
1380 # Common NUMA Features
1381 config NUMA
1382 bool "Numa Memory Allocation and Scheduler Support"
1383 depends on SMP
1384 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1385 default y if X86_BIGSMP
1386 ---help---
1387 Enable NUMA (Non Uniform Memory Access) support.
1389 The kernel will try to allocate memory used by a CPU on the
1390 local memory controller of the CPU and add some more
1391 NUMA awareness to the kernel.
1393 For 64-bit this is recommended if the system is Intel Core i7
1394 (or later), AMD Opteron, or EM64T NUMA.
1396 For 32-bit this is only needed if you boot a 32-bit
1397 kernel on a 64-bit NUMA platform.
1399 Otherwise, you should say N.
1401 config AMD_NUMA
1402 def_bool y
1403 prompt "Old style AMD Opteron NUMA detection"
1404 depends on X86_64 && NUMA && PCI
1405 ---help---
1406 Enable AMD NUMA node topology detection. You should say Y here if
1407 you have a multi processor AMD system. This uses an old method to
1408 read the NUMA configuration directly from the builtin Northbridge
1409 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1410 which also takes priority if both are compiled in.
1412 config X86_64_ACPI_NUMA
1413 def_bool y
1414 prompt "ACPI NUMA detection"
1415 depends on X86_64 && NUMA && ACPI && PCI
1416 select ACPI_NUMA
1417 ---help---
1418 Enable ACPI SRAT based node topology detection.
1420 # Some NUMA nodes have memory ranges that span
1421 # other nodes. Even though a pfn is valid and
1422 # between a node's start and end pfns, it may not
1423 # reside on that node. See memmap_init_zone()
1424 # for details.
1425 config NODES_SPAN_OTHER_NODES
1426 def_bool y
1427 depends on X86_64_ACPI_NUMA
1429 config NUMA_EMU
1430 bool "NUMA emulation"
1431 depends on NUMA
1432 ---help---
1433 Enable NUMA emulation. A flat machine will be split
1434 into virtual nodes when booted with "numa=fake=N", where N is the
1435 number of nodes. This is only useful for debugging.
1437 config NODES_SHIFT
1438 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1439 range 1 10
1440 default "10" if MAXSMP
1441 default "6" if X86_64
1442 default "3"
1443 depends on NEED_MULTIPLE_NODES
1444 ---help---
1445 Specify the maximum number of NUMA Nodes available on the target
1446 system. Increases memory reserved to accommodate various tables.
1448 config ARCH_HAVE_MEMORY_PRESENT
1449 def_bool y
1450 depends on X86_32 && DISCONTIGMEM
1452 config NEED_NODE_MEMMAP_SIZE
1453 def_bool y
1454 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1456 config ARCH_FLATMEM_ENABLE
1457 def_bool y
1458 depends on X86_32 && !NUMA
1460 config ARCH_DISCONTIGMEM_ENABLE
1461 def_bool y
1462 depends on NUMA && X86_32
1464 config ARCH_DISCONTIGMEM_DEFAULT
1465 def_bool y
1466 depends on NUMA && X86_32
1468 config ARCH_SPARSEMEM_ENABLE
1469 def_bool y
1470 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1471 select SPARSEMEM_STATIC if X86_32
1472 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1474 config ARCH_SPARSEMEM_DEFAULT
1475 def_bool y
1476 depends on X86_64
1478 config ARCH_SELECT_MEMORY_MODEL
1479 def_bool y
1480 depends on ARCH_SPARSEMEM_ENABLE
1482 config ARCH_MEMORY_PROBE
1483 bool "Enable sysfs memory/probe interface"
1484 depends on X86_64 && MEMORY_HOTPLUG
1485 help
1486 This option enables a sysfs memory/probe interface for testing.
1487 See Documentation/memory-hotplug.txt for more information.
1488 If you are unsure how to answer this question, answer N.
1490 config ARCH_PROC_KCORE_TEXT
1491 def_bool y
1492 depends on X86_64 && PROC_KCORE
1494 config ILLEGAL_POINTER_VALUE
1495 hex
1496 default 0 if X86_32
1497 default 0xdead000000000000 if X86_64
1499 source "mm/Kconfig"
1501 config X86_PMEM_LEGACY_DEVICE
1502 bool
1504 config X86_PMEM_LEGACY
1505 tristate "Support non-standard NVDIMMs and ADR protected memory"
1506 depends on PHYS_ADDR_T_64BIT
1507 depends on BLK_DEV
1508 select X86_PMEM_LEGACY_DEVICE
1509 select LIBNVDIMM
1510 help
1511 Treat memory marked using the non-standard e820 type of 12 as used
1512 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1513 The kernel will offer these regions to the 'pmem' driver so
1514 they can be used for persistent storage.
1516 Say Y if unsure.
1518 config HIGHPTE
1519 bool "Allocate 3rd-level pagetables from highmem"
1520 depends on HIGHMEM
1521 ---help---
1522 The VM uses one page table entry for each page of physical memory.
1523 For systems with a lot of RAM, this can be wasteful of precious
1524 low memory. Setting this option will put user-space page table
1525 entries in high memory.
1527 config X86_CHECK_BIOS_CORRUPTION
1528 bool "Check for low memory corruption"
1529 ---help---
1530 Periodically check for memory corruption in low memory, which
1531 is suspected to be caused by BIOS. Even when enabled in the
1532 configuration, it is disabled at runtime. Enable it by
1533 setting "memory_corruption_check=1" on the kernel command
1534 line. By default it scans the low 64k of memory every 60
1535 seconds; see the memory_corruption_check_size and
1536 memory_corruption_check_period parameters in
1537 Documentation/kernel-parameters.txt to adjust this.
1539 When enabled with the default parameters, this option has
1540 almost no overhead, as it reserves a relatively small amount
1541 of memory and scans it infrequently. It both detects corruption
1542 and prevents it from affecting the running system.
1544 It is, however, intended as a diagnostic tool; if repeatable
1545 BIOS-originated corruption always affects the same memory,
1546 you can use memmap= to prevent the kernel from using that
1547 memory.
1549 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1550 bool "Set the default setting of memory_corruption_check"
1551 depends on X86_CHECK_BIOS_CORRUPTION
1552 default y
1553 ---help---
1554 Set whether the default state of memory_corruption_check is
1555 on or off.
1557 config X86_RESERVE_LOW
1558 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1559 default 64
1560 range 4 640
1561 ---help---
1562 Specify the amount of low memory to reserve for the BIOS.
1564 The first page contains BIOS data structures that the kernel
1565 must not use, so that page must always be reserved.
1567 By default we reserve the first 64K of physical RAM, as a
1568 number of BIOSes are known to corrupt that memory range
1569 during events such as suspend/resume or monitor cable
1570 insertion, so it must not be used by the kernel.
1572 You can set this to 4 if you are absolutely sure that you
1573 trust the BIOS to get all its memory reservations and usages
1574 right. If you know your BIOS have problems beyond the
1575 default 64K area, you can set this to 640 to avoid using the
1576 entire low memory range.
1578 If you have doubts about the BIOS (e.g. suspend/resume does
1579 not work or there's kernel crashes after certain hardware
1580 hotplug events) then you might want to enable
1581 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1582 typical corruption patterns.
1584 Leave this to the default value of 64 if you are unsure.
1586 config MATH_EMULATION
1587 bool
1588 depends on MODIFY_LDT_SYSCALL
1589 prompt "Math emulation" if X86_32
1590 ---help---
1591 Linux can emulate a math coprocessor (used for floating point
1592 operations) if you don't have one. 486DX and Pentium processors have
1593 a math coprocessor built in, 486SX and 386 do not, unless you added
1594 a 487DX or 387, respectively. (The messages during boot time can
1595 give you some hints here ["man dmesg"].) Everyone needs either a
1596 coprocessor or this emulation.
1598 If you don't have a math coprocessor, you need to say Y here; if you
1599 say Y here even though you have a coprocessor, the coprocessor will
1600 be used nevertheless. (This behavior can be changed with the kernel
1601 command line option "no387", which comes handy if your coprocessor
1602 is broken. Try "man bootparam" or see the documentation of your boot
1603 loader (lilo or loadlin) about how to pass options to the kernel at
1604 boot time.) This means that it is a good idea to say Y here if you
1605 intend to use this kernel on different machines.
1607 More information about the internals of the Linux math coprocessor
1608 emulation can be found in <file:arch/x86/math-emu/README>.
1610 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1611 kernel, it won't hurt.
1613 config MTRR
1614 def_bool y
1615 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1616 ---help---
1617 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1618 the Memory Type Range Registers (MTRRs) may be used to control
1619 processor access to memory ranges. This is most useful if you have
1620 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1621 allows bus write transfers to be combined into a larger transfer
1622 before bursting over the PCI/AGP bus. This can increase performance
1623 of image write operations 2.5 times or more. Saying Y here creates a
1624 /proc/mtrr file which may be used to manipulate your processor's
1625 MTRRs. Typically the X server should use this.
1627 This code has a reasonably generic interface so that similar
1628 control registers on other processors can be easily supported
1629 as well:
1631 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1632 Registers (ARRs) which provide a similar functionality to MTRRs. For
1633 these, the ARRs are used to emulate the MTRRs.
1634 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1635 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1636 write-combining. All of these processors are supported by this code
1637 and it makes sense to say Y here if you have one of them.
1639 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1640 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1641 can lead to all sorts of problems, so it's good to say Y here.
1643 You can safely say Y even if your machine doesn't have MTRRs, you'll
1644 just add about 9 KB to your kernel.
1646 See <file:Documentation/x86/mtrr.txt> for more information.
1648 config MTRR_SANITIZER
1649 def_bool y
1650 prompt "MTRR cleanup support"
1651 depends on MTRR
1652 ---help---
1653 Convert MTRR layout from continuous to discrete, so X drivers can
1654 add writeback entries.
1656 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1657 The largest mtrr entry size for a continuous block can be set with
1658 mtrr_chunk_size.
1660 If unsure, say Y.
1662 config MTRR_SANITIZER_ENABLE_DEFAULT
1663 int "MTRR cleanup enable value (0-1)"
1664 range 0 1
1665 default "0"
1666 depends on MTRR_SANITIZER
1667 ---help---
1668 Enable mtrr cleanup default value
1670 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1671 int "MTRR cleanup spare reg num (0-7)"
1672 range 0 7
1673 default "1"
1674 depends on MTRR_SANITIZER
1675 ---help---
1676 mtrr cleanup spare entries default, it can be changed via
1677 mtrr_spare_reg_nr=N on the kernel command line.
1679 config X86_PAT
1680 def_bool y
1681 prompt "x86 PAT support" if EXPERT
1682 depends on MTRR
1683 ---help---
1684 Use PAT attributes to setup page level cache control.
1686 PATs are the modern equivalents of MTRRs and are much more
1687 flexible than MTRRs.
1689 Say N here if you see bootup problems (boot crash, boot hang,
1690 spontaneous reboots) or a non-working video driver.
1692 If unsure, say Y.
1694 config ARCH_USES_PG_UNCACHED
1695 def_bool y
1696 depends on X86_PAT
1698 config ARCH_RANDOM
1699 def_bool y
1700 prompt "x86 architectural random number generator" if EXPERT
1701 ---help---
1702 Enable the x86 architectural RDRAND instruction
1703 (Intel Bull Mountain technology) to generate random numbers.
1704 If supported, this is a high bandwidth, cryptographically
1705 secure hardware random number generator.
1707 config X86_SMAP
1708 def_bool y
1709 prompt "Supervisor Mode Access Prevention" if EXPERT
1710 ---help---
1711 Supervisor Mode Access Prevention (SMAP) is a security
1712 feature in newer Intel processors. There is a small
1713 performance cost if this enabled and turned on; there is
1714 also a small increase in the kernel size if this is enabled.
1716 If unsure, say Y.
1718 config X86_INTEL_MPX
1719 prompt "Intel MPX (Memory Protection Extensions)"
1720 def_bool n
1721 depends on CPU_SUP_INTEL
1722 ---help---
1723 MPX provides hardware features that can be used in
1724 conjunction with compiler-instrumented code to check
1725 memory references. It is designed to detect buffer
1726 overflow or underflow bugs.
1728 This option enables running applications which are
1729 instrumented or otherwise use MPX. It does not use MPX
1730 itself inside the kernel or to protect the kernel
1731 against bad memory references.
1733 Enabling this option will make the kernel larger:
1734 ~8k of kernel text and 36 bytes of data on a 64-bit
1735 defconfig. It adds a long to the 'mm_struct' which
1736 will increase the kernel memory overhead of each
1737 process and adds some branches to paths used during
1738 exec() and munmap().
1740 For details, see Documentation/x86/intel_mpx.txt
1742 If unsure, say N.
1744 config X86_INTEL_MEMORY_PROTECTION_KEYS
1745 prompt "Intel Memory Protection Keys"
1746 def_bool y
1747 # Note: only available in 64-bit mode
1748 depends on CPU_SUP_INTEL && X86_64
1749 ---help---
1750 Memory Protection Keys provides a mechanism for enforcing
1751 page-based protections, but without requiring modification of the
1752 page tables when an application changes protection domains.
1754 For details, see Documentation/x86/protection-keys.txt
1756 If unsure, say y.
1758 config EFI
1759 bool "EFI runtime service support"
1760 depends on ACPI
1761 select UCS2_STRING
1762 select EFI_RUNTIME_WRAPPERS
1763 ---help---
1764 This enables the kernel to use EFI runtime services that are
1765 available (such as the EFI variable services).
1767 This option is only useful on systems that have EFI firmware.
1768 In addition, you should use the latest ELILO loader available
1769 at <http://elilo.sourceforge.net> in order to take advantage
1770 of EFI runtime services. However, even with this option, the
1771 resultant kernel should continue to boot on existing non-EFI
1772 platforms.
1774 config EFI_STUB
1775 bool "EFI stub support"
1776 depends on EFI && !X86_USE_3DNOW
1777 select RELOCATABLE
1778 ---help---
1779 This kernel feature allows a bzImage to be loaded directly
1780 by EFI firmware without the use of a bootloader.
1782 See Documentation/efi-stub.txt for more information.
1784 config EFI_MIXED
1785 bool "EFI mixed-mode support"
1786 depends on EFI_STUB && X86_64
1787 ---help---
1788 Enabling this feature allows a 64-bit kernel to be booted
1789 on a 32-bit firmware, provided that your CPU supports 64-bit
1790 mode.
1792 Note that it is not possible to boot a mixed-mode enabled
1793 kernel via the EFI boot stub - a bootloader that supports
1794 the EFI handover protocol must be used.
1796 If unsure, say N.
1798 config SECCOMP
1799 def_bool y
1800 prompt "Enable seccomp to safely compute untrusted bytecode"
1801 ---help---
1802 This kernel feature is useful for number crunching applications
1803 that may need to compute untrusted bytecode during their
1804 execution. By using pipes or other transports made available to
1805 the process as file descriptors supporting the read/write
1806 syscalls, it's possible to isolate those applications in
1807 their own address space using seccomp. Once seccomp is
1808 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1809 and the task is only allowed to execute a few safe syscalls
1810 defined by each seccomp mode.
1812 If unsure, say Y. Only embedded should say N here.
1814 source kernel/Kconfig.hz
1816 config KEXEC
1817 bool "kexec system call"
1818 select KEXEC_CORE
1819 ---help---
1820 kexec is a system call that implements the ability to shutdown your
1821 current kernel, and to start another kernel. It is like a reboot
1822 but it is independent of the system firmware. And like a reboot
1823 you can start any kernel with it, not just Linux.
1825 The name comes from the similarity to the exec system call.
1827 It is an ongoing process to be certain the hardware in a machine
1828 is properly shutdown, so do not be surprised if this code does not
1829 initially work for you. As of this writing the exact hardware
1830 interface is strongly in flux, so no good recommendation can be
1831 made.
1833 config KEXEC_FILE
1834 bool "kexec file based system call"
1835 select KEXEC_CORE
1836 select BUILD_BIN2C
1837 depends on X86_64
1838 depends on CRYPTO=y
1839 depends on CRYPTO_SHA256=y
1840 ---help---
1841 This is new version of kexec system call. This system call is
1842 file based and takes file descriptors as system call argument
1843 for kernel and initramfs as opposed to list of segments as
1844 accepted by previous system call.
1846 config KEXEC_VERIFY_SIG
1847 bool "Verify kernel signature during kexec_file_load() syscall"
1848 depends on KEXEC_FILE
1849 ---help---
1850 This option makes kernel signature verification mandatory for
1851 the kexec_file_load() syscall.
1853 In addition to that option, you need to enable signature
1854 verification for the corresponding kernel image type being
1855 loaded in order for this to work.
1857 config KEXEC_BZIMAGE_VERIFY_SIG
1858 bool "Enable bzImage signature verification support"
1859 depends on KEXEC_VERIFY_SIG
1860 depends on SIGNED_PE_FILE_VERIFICATION
1861 select SYSTEM_TRUSTED_KEYRING
1862 ---help---
1863 Enable bzImage signature verification support.
1865 config CRASH_DUMP
1866 bool "kernel crash dumps"
1867 depends on X86_64 || (X86_32 && HIGHMEM)
1868 ---help---
1869 Generate crash dump after being started by kexec.
1870 This should be normally only set in special crash dump kernels
1871 which are loaded in the main kernel with kexec-tools into
1872 a specially reserved region and then later executed after
1873 a crash by kdump/kexec. The crash dump kernel must be compiled
1874 to a memory address not used by the main kernel or BIOS using
1875 PHYSICAL_START, or it must be built as a relocatable image
1876 (CONFIG_RELOCATABLE=y).
1877 For more details see Documentation/kdump/kdump.txt
1879 config KEXEC_JUMP
1880 bool "kexec jump"
1881 depends on KEXEC && HIBERNATION
1882 ---help---
1883 Jump between original kernel and kexeced kernel and invoke
1884 code in physical address mode via KEXEC
1886 config PHYSICAL_START
1887 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1888 default "0x1000000"
1889 ---help---
1890 This gives the physical address where the kernel is loaded.
1892 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1893 bzImage will decompress itself to above physical address and
1894 run from there. Otherwise, bzImage will run from the address where
1895 it has been loaded by the boot loader and will ignore above physical
1896 address.
1898 In normal kdump cases one does not have to set/change this option
1899 as now bzImage can be compiled as a completely relocatable image
1900 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1901 address. This option is mainly useful for the folks who don't want
1902 to use a bzImage for capturing the crash dump and want to use a
1903 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1904 to be specifically compiled to run from a specific memory area
1905 (normally a reserved region) and this option comes handy.
1907 So if you are using bzImage for capturing the crash dump,
1908 leave the value here unchanged to 0x1000000 and set
1909 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1910 for capturing the crash dump change this value to start of
1911 the reserved region. In other words, it can be set based on
1912 the "X" value as specified in the "crashkernel=YM@XM"
1913 command line boot parameter passed to the panic-ed
1914 kernel. Please take a look at Documentation/kdump/kdump.txt
1915 for more details about crash dumps.
1917 Usage of bzImage for capturing the crash dump is recommended as
1918 one does not have to build two kernels. Same kernel can be used
1919 as production kernel and capture kernel. Above option should have
1920 gone away after relocatable bzImage support is introduced. But it
1921 is present because there are users out there who continue to use
1922 vmlinux for dump capture. This option should go away down the
1923 line.
1925 Don't change this unless you know what you are doing.
1927 config RELOCATABLE
1928 bool "Build a relocatable kernel"
1929 default y
1930 ---help---
1931 This builds a kernel image that retains relocation information
1932 so it can be loaded someplace besides the default 1MB.
1933 The relocations tend to make the kernel binary about 10% larger,
1934 but are discarded at runtime.
1936 One use is for the kexec on panic case where the recovery kernel
1937 must live at a different physical address than the primary
1938 kernel.
1940 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1941 it has been loaded at and the compile time physical address
1942 (CONFIG_PHYSICAL_START) is used as the minimum location.
1944 config RANDOMIZE_BASE
1945 bool "Randomize the address of the kernel image (KASLR)"
1946 depends on RELOCATABLE
1947 default n
1948 ---help---
1949 In support of Kernel Address Space Layout Randomization (KASLR),
1950 this randomizes the physical address at which the kernel image
1951 is decompressed and the virtual address where the kernel
1952 image is mapped, as a security feature that deters exploit
1953 attempts relying on knowledge of the location of kernel
1954 code internals.
1956 On 64-bit, the kernel physical and virtual addresses are
1957 randomized separately. The physical address will be anywhere
1958 between 16MB and the top of physical memory (up to 64TB). The
1959 virtual address will be randomized from 16MB up to 1GB (9 bits
1960 of entropy). Note that this also reduces the memory space
1961 available to kernel modules from 1.5GB to 1GB.
1963 On 32-bit, the kernel physical and virtual addresses are
1964 randomized together. They will be randomized from 16MB up to
1965 512MB (8 bits of entropy).
1967 Entropy is generated using the RDRAND instruction if it is
1968 supported. If RDTSC is supported, its value is mixed into
1969 the entropy pool as well. If neither RDRAND nor RDTSC are
1970 supported, then entropy is read from the i8254 timer. The
1971 usable entropy is limited by the kernel being built using
1972 2GB addressing, and that PHYSICAL_ALIGN must be at a
1973 minimum of 2MB. As a result, only 10 bits of entropy are
1974 theoretically possible, but the implementations are further
1975 limited due to memory layouts.
1977 If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot
1978 time. To enable it, boot with "kaslr" on the kernel command
1979 line (which will also disable hibernation).
1981 If unsure, say N.
1983 # Relocation on x86 needs some additional build support
1984 config X86_NEED_RELOCS
1985 def_bool y
1986 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1988 config PHYSICAL_ALIGN
1989 hex "Alignment value to which kernel should be aligned"
1990 default "0x200000"
1991 range 0x2000 0x1000000 if X86_32
1992 range 0x200000 0x1000000 if X86_64
1993 ---help---
1994 This value puts the alignment restrictions on physical address
1995 where kernel is loaded and run from. Kernel is compiled for an
1996 address which meets above alignment restriction.
1998 If bootloader loads the kernel at a non-aligned address and
1999 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
2000 address aligned to above value and run from there.
2002 If bootloader loads the kernel at a non-aligned address and
2003 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
2004 load address and decompress itself to the address it has been
2005 compiled for and run from there. The address for which kernel is
2006 compiled already meets above alignment restrictions. Hence the
2007 end result is that kernel runs from a physical address meeting
2008 above alignment restrictions.
2010 On 32-bit this value must be a multiple of 0x2000. On 64-bit
2011 this value must be a multiple of 0x200000.
2013 Don't change this unless you know what you are doing.
2015 config RANDOMIZE_MEMORY
2016 bool "Randomize the kernel memory sections"
2017 depends on X86_64
2018 depends on RANDOMIZE_BASE
2019 default RANDOMIZE_BASE
2020 ---help---
2021 Randomizes the base virtual address of kernel memory sections
2022 (physical memory mapping, vmalloc & vmemmap). This security feature
2023 makes exploits relying on predictable memory locations less reliable.
2025 The order of allocations remains unchanged. Entropy is generated in
2026 the same way as RANDOMIZE_BASE. Current implementation in the optimal
2027 configuration have in average 30,000 different possible virtual
2028 addresses for each memory section.
2030 If unsure, say N.
2032 config RANDOMIZE_MEMORY_PHYSICAL_PADDING
2033 hex "Physical memory mapping padding" if EXPERT
2034 depends on RANDOMIZE_MEMORY
2035 default "0xa" if MEMORY_HOTPLUG
2036 default "0x0"
2037 range 0x1 0x40 if MEMORY_HOTPLUG
2038 range 0x0 0x40
2039 ---help---
2040 Define the padding in terabytes added to the existing physical
2041 memory size during kernel memory randomization. It is useful
2042 for memory hotplug support but reduces the entropy available for
2043 address randomization.
2045 If unsure, leave at the default value.
2047 config HOTPLUG_CPU
2048 def_bool y
2049 depends on SMP
2051 config BOOTPARAM_HOTPLUG_CPU0
2052 bool "Set default setting of cpu0_hotpluggable"
2053 default n
2054 depends on HOTPLUG_CPU
2055 ---help---
2056 Set whether default state of cpu0_hotpluggable is on or off.
2058 Say Y here to enable CPU0 hotplug by default. If this switch
2059 is turned on, there is no need to give cpu0_hotplug kernel
2060 parameter and the CPU0 hotplug feature is enabled by default.
2062 Please note: there are two known CPU0 dependencies if you want
2063 to enable the CPU0 hotplug feature either by this switch or by
2064 cpu0_hotplug kernel parameter.
2066 First, resume from hibernate or suspend always starts from CPU0.
2067 So hibernate and suspend are prevented if CPU0 is offline.
2069 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2070 offline if any interrupt can not migrate out of CPU0. There may
2071 be other CPU0 dependencies.
2073 Please make sure the dependencies are under your control before
2074 you enable this feature.
2076 Say N if you don't want to enable CPU0 hotplug feature by default.
2077 You still can enable the CPU0 hotplug feature at boot by kernel
2078 parameter cpu0_hotplug.
2080 config DEBUG_HOTPLUG_CPU0
2081 def_bool n
2082 prompt "Debug CPU0 hotplug"
2083 depends on HOTPLUG_CPU
2084 ---help---
2085 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2086 soon as possible and boots up userspace with CPU0 offlined. User
2087 can online CPU0 back after boot time.
2089 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2090 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2091 compilation or giving cpu0_hotplug kernel parameter at boot.
2093 If unsure, say N.
2095 config COMPAT_VDSO
2096 def_bool n
2097 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2098 depends on X86_32 || IA32_EMULATION
2099 ---help---
2100 Certain buggy versions of glibc will crash if they are
2101 presented with a 32-bit vDSO that is not mapped at the address
2102 indicated in its segment table.
2104 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2105 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2106 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2107 the only released version with the bug, but OpenSUSE 9
2108 contains a buggy "glibc 2.3.2".
2110 The symptom of the bug is that everything crashes on startup, saying:
2111 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2113 Saying Y here changes the default value of the vdso32 boot
2114 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2115 This works around the glibc bug but hurts performance.
2117 If unsure, say N: if you are compiling your own kernel, you
2118 are unlikely to be using a buggy version of glibc.
2120 choice
2121 prompt "vsyscall table for legacy applications"
2122 depends on X86_64
2123 default LEGACY_VSYSCALL_EMULATE
2124 help
2125 Legacy user code that does not know how to find the vDSO expects
2126 to be able to issue three syscalls by calling fixed addresses in
2127 kernel space. Since this location is not randomized with ASLR,
2128 it can be used to assist security vulnerability exploitation.
2130 This setting can be changed at boot time via the kernel command
2131 line parameter vsyscall=[native|emulate|none].
2133 On a system with recent enough glibc (2.14 or newer) and no
2134 static binaries, you can say None without a performance penalty
2135 to improve security.
2137 If unsure, select "Emulate".
2139 config LEGACY_VSYSCALL_NATIVE
2140 bool "Native"
2141 help
2142 Actual executable code is located in the fixed vsyscall
2143 address mapping, implementing time() efficiently. Since
2144 this makes the mapping executable, it can be used during
2145 security vulnerability exploitation (traditionally as
2146 ROP gadgets). This configuration is not recommended.
2148 config LEGACY_VSYSCALL_EMULATE
2149 bool "Emulate"
2150 help
2151 The kernel traps and emulates calls into the fixed
2152 vsyscall address mapping. This makes the mapping
2153 non-executable, but it still contains known contents,
2154 which could be used in certain rare security vulnerability
2155 exploits. This configuration is recommended when userspace
2156 still uses the vsyscall area.
2158 config LEGACY_VSYSCALL_NONE
2159 bool "None"
2160 help
2161 There will be no vsyscall mapping at all. This will
2162 eliminate any risk of ASLR bypass due to the vsyscall
2163 fixed address mapping. Attempts to use the vsyscalls
2164 will be reported to dmesg, so that either old or
2165 malicious userspace programs can be identified.
2167 endchoice
2169 config CMDLINE_BOOL
2170 bool "Built-in kernel command line"
2171 ---help---
2172 Allow for specifying boot arguments to the kernel at
2173 build time. On some systems (e.g. embedded ones), it is
2174 necessary or convenient to provide some or all of the
2175 kernel boot arguments with the kernel itself (that is,
2176 to not rely on the boot loader to provide them.)
2178 To compile command line arguments into the kernel,
2179 set this option to 'Y', then fill in the
2180 boot arguments in CONFIG_CMDLINE.
2182 Systems with fully functional boot loaders (i.e. non-embedded)
2183 should leave this option set to 'N'.
2185 config CMDLINE
2186 string "Built-in kernel command string"
2187 depends on CMDLINE_BOOL
2188 default ""
2189 ---help---
2190 Enter arguments here that should be compiled into the kernel
2191 image and used at boot time. If the boot loader provides a
2192 command line at boot time, it is appended to this string to
2193 form the full kernel command line, when the system boots.
2195 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2196 change this behavior.
2198 In most cases, the command line (whether built-in or provided
2199 by the boot loader) should specify the device for the root
2200 file system.
2202 config CMDLINE_OVERRIDE
2203 bool "Built-in command line overrides boot loader arguments"
2204 depends on CMDLINE_BOOL
2205 ---help---
2206 Set this option to 'Y' to have the kernel ignore the boot loader
2207 command line, and use ONLY the built-in command line.
2209 This is used to work around broken boot loaders. This should
2210 be set to 'N' under normal conditions.
2212 config MODIFY_LDT_SYSCALL
2213 bool "Enable the LDT (local descriptor table)" if EXPERT
2214 default y
2215 ---help---
2216 Linux can allow user programs to install a per-process x86
2217 Local Descriptor Table (LDT) using the modify_ldt(2) system
2218 call. This is required to run 16-bit or segmented code such as
2219 DOSEMU or some Wine programs. It is also used by some very old
2220 threading libraries.
2222 Enabling this feature adds a small amount of overhead to
2223 context switches and increases the low-level kernel attack
2224 surface. Disabling it removes the modify_ldt(2) system call.
2226 Saying 'N' here may make sense for embedded or server kernels.
2228 source "kernel/livepatch/Kconfig"
2230 endmenu
2232 config ARCH_ENABLE_MEMORY_HOTPLUG
2233 def_bool y
2234 depends on X86_64 || (X86_32 && HIGHMEM)
2236 config ARCH_ENABLE_MEMORY_HOTREMOVE
2237 def_bool y
2238 depends on MEMORY_HOTPLUG
2240 config USE_PERCPU_NUMA_NODE_ID
2241 def_bool y
2242 depends on NUMA
2244 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2245 def_bool y
2246 depends on X86_64 || X86_PAE
2248 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2249 def_bool y
2250 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2252 menu "Power management and ACPI options"
2254 config ARCH_HIBERNATION_HEADER
2255 def_bool y
2256 depends on X86_64 && HIBERNATION
2258 source "kernel/power/Kconfig"
2260 source "drivers/acpi/Kconfig"
2262 source "drivers/sfi/Kconfig"
2264 config X86_APM_BOOT
2265 def_bool y
2266 depends on APM
2268 menuconfig APM
2269 tristate "APM (Advanced Power Management) BIOS support"
2270 depends on X86_32 && PM_SLEEP
2271 ---help---
2272 APM is a BIOS specification for saving power using several different
2273 techniques. This is mostly useful for battery powered laptops with
2274 APM compliant BIOSes. If you say Y here, the system time will be
2275 reset after a RESUME operation, the /proc/apm device will provide
2276 battery status information, and user-space programs will receive
2277 notification of APM "events" (e.g. battery status change).
2279 If you select "Y" here, you can disable actual use of the APM
2280 BIOS by passing the "apm=off" option to the kernel at boot time.
2282 Note that the APM support is almost completely disabled for
2283 machines with more than one CPU.
2285 In order to use APM, you will need supporting software. For location
2286 and more information, read <file:Documentation/power/apm-acpi.txt>
2287 and the Battery Powered Linux mini-HOWTO, available from
2288 <http://www.tldp.org/docs.html#howto>.
2290 This driver does not spin down disk drives (see the hdparm(8)
2291 manpage ("man 8 hdparm") for that), and it doesn't turn off
2292 VESA-compliant "green" monitors.
2294 This driver does not support the TI 4000M TravelMate and the ACER
2295 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2296 desktop machines also don't have compliant BIOSes, and this driver
2297 may cause those machines to panic during the boot phase.
2299 Generally, if you don't have a battery in your machine, there isn't
2300 much point in using this driver and you should say N. If you get
2301 random kernel OOPSes or reboots that don't seem to be related to
2302 anything, try disabling/enabling this option (or disabling/enabling
2303 APM in your BIOS).
2305 Some other things you should try when experiencing seemingly random,
2306 "weird" problems:
2308 1) make sure that you have enough swap space and that it is
2309 enabled.
2310 2) pass the "no-hlt" option to the kernel
2311 3) switch on floating point emulation in the kernel and pass
2312 the "no387" option to the kernel
2313 4) pass the "floppy=nodma" option to the kernel
2314 5) pass the "mem=4M" option to the kernel (thereby disabling
2315 all but the first 4 MB of RAM)
2316 6) make sure that the CPU is not over clocked.
2317 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2318 8) disable the cache from your BIOS settings
2319 9) install a fan for the video card or exchange video RAM
2320 10) install a better fan for the CPU
2321 11) exchange RAM chips
2322 12) exchange the motherboard.
2324 To compile this driver as a module, choose M here: the
2325 module will be called apm.
2327 if APM
2329 config APM_IGNORE_USER_SUSPEND
2330 bool "Ignore USER SUSPEND"
2331 ---help---
2332 This option will ignore USER SUSPEND requests. On machines with a
2333 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2334 series notebooks, it is necessary to say Y because of a BIOS bug.
2336 config APM_DO_ENABLE
2337 bool "Enable PM at boot time"
2338 ---help---
2339 Enable APM features at boot time. From page 36 of the APM BIOS
2340 specification: "When disabled, the APM BIOS does not automatically
2341 power manage devices, enter the Standby State, enter the Suspend
2342 State, or take power saving steps in response to CPU Idle calls."
2343 This driver will make CPU Idle calls when Linux is idle (unless this
2344 feature is turned off -- see "Do CPU IDLE calls", below). This
2345 should always save battery power, but more complicated APM features
2346 will be dependent on your BIOS implementation. You may need to turn
2347 this option off if your computer hangs at boot time when using APM
2348 support, or if it beeps continuously instead of suspending. Turn
2349 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2350 T400CDT. This is off by default since most machines do fine without
2351 this feature.
2353 config APM_CPU_IDLE
2354 depends on CPU_IDLE
2355 bool "Make CPU Idle calls when idle"
2356 ---help---
2357 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2358 On some machines, this can activate improved power savings, such as
2359 a slowed CPU clock rate, when the machine is idle. These idle calls
2360 are made after the idle loop has run for some length of time (e.g.,
2361 333 mS). On some machines, this will cause a hang at boot time or
2362 whenever the CPU becomes idle. (On machines with more than one CPU,
2363 this option does nothing.)
2365 config APM_DISPLAY_BLANK
2366 bool "Enable console blanking using APM"
2367 ---help---
2368 Enable console blanking using the APM. Some laptops can use this to
2369 turn off the LCD backlight when the screen blanker of the Linux
2370 virtual console blanks the screen. Note that this is only used by
2371 the virtual console screen blanker, and won't turn off the backlight
2372 when using the X Window system. This also doesn't have anything to
2373 do with your VESA-compliant power-saving monitor. Further, this
2374 option doesn't work for all laptops -- it might not turn off your
2375 backlight at all, or it might print a lot of errors to the console,
2376 especially if you are using gpm.
2378 config APM_ALLOW_INTS
2379 bool "Allow interrupts during APM BIOS calls"
2380 ---help---
2381 Normally we disable external interrupts while we are making calls to
2382 the APM BIOS as a measure to lessen the effects of a badly behaving
2383 BIOS implementation. The BIOS should reenable interrupts if it
2384 needs to. Unfortunately, some BIOSes do not -- especially those in
2385 many of the newer IBM Thinkpads. If you experience hangs when you
2386 suspend, try setting this to Y. Otherwise, say N.
2388 endif # APM
2390 source "drivers/cpufreq/Kconfig"
2392 source "drivers/cpuidle/Kconfig"
2394 source "drivers/idle/Kconfig"
2396 endmenu
2399 menu "Bus options (PCI etc.)"
2401 config PCI
2402 bool "PCI support"
2403 default y
2404 ---help---
2405 Find out whether you have a PCI motherboard. PCI is the name of a
2406 bus system, i.e. the way the CPU talks to the other stuff inside
2407 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2408 VESA. If you have PCI, say Y, otherwise N.
2410 choice
2411 prompt "PCI access mode"
2412 depends on X86_32 && PCI
2413 default PCI_GOANY
2414 ---help---
2415 On PCI systems, the BIOS can be used to detect the PCI devices and
2416 determine their configuration. However, some old PCI motherboards
2417 have BIOS bugs and may crash if this is done. Also, some embedded
2418 PCI-based systems don't have any BIOS at all. Linux can also try to
2419 detect the PCI hardware directly without using the BIOS.
2421 With this option, you can specify how Linux should detect the
2422 PCI devices. If you choose "BIOS", the BIOS will be used,
2423 if you choose "Direct", the BIOS won't be used, and if you
2424 choose "MMConfig", then PCI Express MMCONFIG will be used.
2425 If you choose "Any", the kernel will try MMCONFIG, then the
2426 direct access method and falls back to the BIOS if that doesn't
2427 work. If unsure, go with the default, which is "Any".
2429 config PCI_GOBIOS
2430 bool "BIOS"
2432 config PCI_GOMMCONFIG
2433 bool "MMConfig"
2435 config PCI_GODIRECT
2436 bool "Direct"
2438 config PCI_GOOLPC
2439 bool "OLPC XO-1"
2440 depends on OLPC
2442 config PCI_GOANY
2443 bool "Any"
2445 endchoice
2447 config PCI_BIOS
2448 def_bool y
2449 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2451 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2452 config PCI_DIRECT
2453 def_bool y
2454 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2456 config PCI_MMCONFIG
2457 def_bool y
2458 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2460 config PCI_OLPC
2461 def_bool y
2462 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2464 config PCI_XEN
2465 def_bool y
2466 depends on PCI && XEN
2467 select SWIOTLB_XEN
2469 config PCI_DOMAINS
2470 def_bool y
2471 depends on PCI
2473 config PCI_MMCONFIG
2474 bool "Support mmconfig PCI config space access"
2475 depends on X86_64 && PCI && ACPI
2477 config PCI_CNB20LE_QUIRK
2478 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2479 depends on PCI
2480 help
2481 Read the PCI windows out of the CNB20LE host bridge. This allows
2482 PCI hotplug to work on systems with the CNB20LE chipset which do
2483 not have ACPI.
2485 There's no public spec for this chipset, and this functionality
2486 is known to be incomplete.
2488 You should say N unless you know you need this.
2490 source "drivers/pci/Kconfig"
2492 config ISA_BUS
2493 bool "ISA-style bus support on modern systems" if EXPERT
2494 select ISA_BUS_API
2495 help
2496 Enables ISA-style drivers on modern systems. This is necessary to
2497 support PC/104 devices on X86_64 platforms.
2499 If unsure, say N.
2501 # x86_64 have no ISA slots, but can have ISA-style DMA.
2502 config ISA_DMA_API
2503 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2504 default y
2505 help
2506 Enables ISA-style DMA support for devices requiring such controllers.
2507 If unsure, say Y.
2509 if X86_32
2511 config ISA
2512 bool "ISA support"
2513 ---help---
2514 Find out whether you have ISA slots on your motherboard. ISA is the
2515 name of a bus system, i.e. the way the CPU talks to the other stuff
2516 inside your box. Other bus systems are PCI, EISA, MicroChannel
2517 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2518 newer boards don't support it. If you have ISA, say Y, otherwise N.
2520 config EISA
2521 bool "EISA support"
2522 depends on ISA
2523 ---help---
2524 The Extended Industry Standard Architecture (EISA) bus was
2525 developed as an open alternative to the IBM MicroChannel bus.
2527 The EISA bus provided some of the features of the IBM MicroChannel
2528 bus while maintaining backward compatibility with cards made for
2529 the older ISA bus. The EISA bus saw limited use between 1988 and
2530 1995 when it was made obsolete by the PCI bus.
2532 Say Y here if you are building a kernel for an EISA-based machine.
2534 Otherwise, say N.
2536 source "drivers/eisa/Kconfig"
2538 config SCx200
2539 tristate "NatSemi SCx200 support"
2540 ---help---
2541 This provides basic support for National Semiconductor's
2542 (now AMD's) Geode processors. The driver probes for the
2543 PCI-IDs of several on-chip devices, so its a good dependency
2544 for other scx200_* drivers.
2546 If compiled as a module, the driver is named scx200.
2548 config SCx200HR_TIMER
2549 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2550 depends on SCx200
2551 default y
2552 ---help---
2553 This driver provides a clocksource built upon the on-chip
2554 27MHz high-resolution timer. Its also a workaround for
2555 NSC Geode SC-1100's buggy TSC, which loses time when the
2556 processor goes idle (as is done by the scheduler). The
2557 other workaround is idle=poll boot option.
2559 config OLPC
2560 bool "One Laptop Per Child support"
2561 depends on !X86_PAE
2562 select GPIOLIB
2563 select OF
2564 select OF_PROMTREE
2565 select IRQ_DOMAIN
2566 ---help---
2567 Add support for detecting the unique features of the OLPC
2568 XO hardware.
2570 config OLPC_XO1_PM
2571 bool "OLPC XO-1 Power Management"
2572 depends on OLPC && MFD_CS5535 && PM_SLEEP
2573 select MFD_CORE
2574 ---help---
2575 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2577 config OLPC_XO1_RTC
2578 bool "OLPC XO-1 Real Time Clock"
2579 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2580 ---help---
2581 Add support for the XO-1 real time clock, which can be used as a
2582 programmable wakeup source.
2584 config OLPC_XO1_SCI
2585 bool "OLPC XO-1 SCI extras"
2586 depends on OLPC && OLPC_XO1_PM
2587 depends on INPUT=y
2588 select POWER_SUPPLY
2589 select GPIO_CS5535
2590 select MFD_CORE
2591 ---help---
2592 Add support for SCI-based features of the OLPC XO-1 laptop:
2593 - EC-driven system wakeups
2594 - Power button
2595 - Ebook switch
2596 - Lid switch
2597 - AC adapter status updates
2598 - Battery status updates
2600 config OLPC_XO15_SCI
2601 bool "OLPC XO-1.5 SCI extras"
2602 depends on OLPC && ACPI
2603 select POWER_SUPPLY
2604 ---help---
2605 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2606 - EC-driven system wakeups
2607 - AC adapter status updates
2608 - Battery status updates
2610 config ALIX
2611 bool "PCEngines ALIX System Support (LED setup)"
2612 select GPIOLIB
2613 ---help---
2614 This option enables system support for the PCEngines ALIX.
2615 At present this just sets up LEDs for GPIO control on
2616 ALIX2/3/6 boards. However, other system specific setup should
2617 get added here.
2619 Note: You must still enable the drivers for GPIO and LED support
2620 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2622 Note: You have to set alix.force=1 for boards with Award BIOS.
2624 config NET5501
2625 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2626 select GPIOLIB
2627 ---help---
2628 This option enables system support for the Soekris Engineering net5501.
2630 config GEOS
2631 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2632 select GPIOLIB
2633 depends on DMI
2634 ---help---
2635 This option enables system support for the Traverse Technologies GEOS.
2637 config TS5500
2638 bool "Technologic Systems TS-5500 platform support"
2639 depends on MELAN
2640 select CHECK_SIGNATURE
2641 select NEW_LEDS
2642 select LEDS_CLASS
2643 ---help---
2644 This option enables system support for the Technologic Systems TS-5500.
2646 endif # X86_32
2648 config AMD_NB
2649 def_bool y
2650 depends on CPU_SUP_AMD && PCI
2652 source "drivers/pcmcia/Kconfig"
2654 config RAPIDIO
2655 tristate "RapidIO support"
2656 depends on PCI
2657 default n
2658 help
2659 If enabled this option will include drivers and the core
2660 infrastructure code to support RapidIO interconnect devices.
2662 source "drivers/rapidio/Kconfig"
2664 config X86_SYSFB
2665 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2666 help
2667 Firmwares often provide initial graphics framebuffers so the BIOS,
2668 bootloader or kernel can show basic video-output during boot for
2669 user-guidance and debugging. Historically, x86 used the VESA BIOS
2670 Extensions and EFI-framebuffers for this, which are mostly limited
2671 to x86.
2672 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2673 framebuffers so the new generic system-framebuffer drivers can be
2674 used on x86. If the framebuffer is not compatible with the generic
2675 modes, it is adverticed as fallback platform framebuffer so legacy
2676 drivers like efifb, vesafb and uvesafb can pick it up.
2677 If this option is not selected, all system framebuffers are always
2678 marked as fallback platform framebuffers as usual.
2680 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2681 not be able to pick up generic system framebuffers if this option
2682 is selected. You are highly encouraged to enable simplefb as
2683 replacement if you select this option. simplefb can correctly deal
2684 with generic system framebuffers. But you should still keep vesafb
2685 and others enabled as fallback if a system framebuffer is
2686 incompatible with simplefb.
2688 If unsure, say Y.
2690 endmenu
2693 menu "Executable file formats / Emulations"
2695 source "fs/Kconfig.binfmt"
2697 config IA32_EMULATION
2698 bool "IA32 Emulation"
2699 depends on X86_64
2700 select BINFMT_ELF
2701 select COMPAT_BINFMT_ELF
2702 select ARCH_WANT_OLD_COMPAT_IPC
2703 ---help---
2704 Include code to run legacy 32-bit programs under a
2705 64-bit kernel. You should likely turn this on, unless you're
2706 100% sure that you don't have any 32-bit programs left.
2708 config IA32_AOUT
2709 tristate "IA32 a.out support"
2710 depends on IA32_EMULATION
2711 ---help---
2712 Support old a.out binaries in the 32bit emulation.
2714 config X86_X32
2715 bool "x32 ABI for 64-bit mode"
2716 depends on X86_64
2717 ---help---
2718 Include code to run binaries for the x32 native 32-bit ABI
2719 for 64-bit processors. An x32 process gets access to the
2720 full 64-bit register file and wide data path while leaving
2721 pointers at 32 bits for smaller memory footprint.
2723 You will need a recent binutils (2.22 or later) with
2724 elf32_x86_64 support enabled to compile a kernel with this
2725 option set.
2727 config COMPAT
2728 def_bool y
2729 depends on IA32_EMULATION || X86_X32
2731 if COMPAT
2732 config COMPAT_FOR_U64_ALIGNMENT
2733 def_bool y
2735 config SYSVIPC_COMPAT
2736 def_bool y
2737 depends on SYSVIPC
2738 endif
2740 endmenu
2743 config HAVE_ATOMIC_IOMAP
2744 def_bool y
2745 depends on X86_32
2747 config X86_DEV_DMA_OPS
2748 bool
2749 depends on X86_64 || STA2X11
2751 config X86_DMA_REMAP
2752 bool
2753 depends on STA2X11
2755 config PMC_ATOM
2756 def_bool y
2757 depends on PCI
2759 source "net/Kconfig"
2761 source "drivers/Kconfig"
2763 source "drivers/firmware/Kconfig"
2765 source "fs/Kconfig"
2767 source "arch/x86/Kconfig.debug"
2769 source "security/Kconfig"
2771 source "crypto/Kconfig"
2773 source "arch/x86/kvm/Kconfig"
2775 source "lib/Kconfig"