1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH != "i386" 5 ---help--- 6 Say yes to build a 64-bit kernel - formerly known as x86_64 7 Say no to build a 32-bit kernel - formerly known as i386 8 9config X86_32 10 def_bool y 11 depends on !64BIT 12 select CLKSRC_I8253 13 select HAVE_UID16 14 15config X86_64 16 def_bool y 17 depends on 64BIT 18 select X86_DEV_DMA_OPS 19 select ARCH_USE_CMPXCHG_LOCKREF 20 21### Arch settings 22config X86 23 def_bool y 24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 25 select ARCH_MIGHT_HAVE_PC_PARPORT 26 select ARCH_MIGHT_HAVE_PC_SERIO 27 select HAVE_AOUT if X86_32 28 select HAVE_UNSTABLE_SCHED_CLOCK 29 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 30 select ARCH_SUPPORTS_INT128 if X86_64 31 select ARCH_WANTS_PROT_NUMA_PROT_NONE 32 select HAVE_IDE 33 select HAVE_OPROFILE 34 select HAVE_PCSPKR_PLATFORM 35 select HAVE_PERF_EVENTS 36 select HAVE_IOREMAP_PROT 37 select HAVE_KPROBES 38 select HAVE_MEMBLOCK 39 select HAVE_MEMBLOCK_NODE_MAP 40 select ARCH_DISCARD_MEMBLOCK 41 select ARCH_WANT_OPTIONAL_GPIOLIB 42 select ARCH_WANT_FRAME_POINTERS 43 select HAVE_DMA_ATTRS 44 select HAVE_DMA_CONTIGUOUS 45 select HAVE_KRETPROBES 46 select GENERIC_EARLY_IOREMAP 47 select HAVE_OPTPROBES 48 select HAVE_KPROBES_ON_FTRACE 49 select HAVE_FTRACE_MCOUNT_RECORD 50 select HAVE_FENTRY if X86_64 51 select HAVE_C_RECORDMCOUNT 52 select HAVE_DYNAMIC_FTRACE 53 select HAVE_DYNAMIC_FTRACE_WITH_REGS 54 select HAVE_FUNCTION_TRACER 55 select HAVE_FUNCTION_GRAPH_TRACER 56 select HAVE_FUNCTION_GRAPH_FP_TEST 57 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 58 select HAVE_SYSCALL_TRACEPOINTS 59 select SYSCTL_EXCEPTION_TRACE 60 select HAVE_KVM 61 select HAVE_ARCH_KGDB 62 select HAVE_ARCH_TRACEHOOK 63 select HAVE_GENERIC_DMA_COHERENT if X86_32 64 select HAVE_EFFICIENT_UNALIGNED_ACCESS 65 select USER_STACKTRACE_SUPPORT 66 select HAVE_REGS_AND_STACK_ACCESS_API 67 select HAVE_DMA_API_DEBUG 68 select HAVE_KERNEL_GZIP 69 select HAVE_KERNEL_BZIP2 70 select HAVE_KERNEL_LZMA 71 select HAVE_KERNEL_XZ 72 select HAVE_KERNEL_LZO 73 select HAVE_KERNEL_LZ4 74 select HAVE_HW_BREAKPOINT 75 select HAVE_MIXED_BREAKPOINTS_REGS 76 select PERF_EVENTS 77 select HAVE_PERF_EVENTS_NMI 78 select HAVE_PERF_REGS 79 select HAVE_PERF_USER_STACK_DUMP 80 select HAVE_DEBUG_KMEMLEAK 81 select ANON_INODES 82 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 83 select HAVE_CMPXCHG_LOCAL 84 select HAVE_CMPXCHG_DOUBLE 85 select HAVE_ARCH_KMEMCHECK 86 select HAVE_USER_RETURN_NOTIFIER 87 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 88 select HAVE_ARCH_JUMP_LABEL 89 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 90 select SPARSE_IRQ 91 select GENERIC_FIND_FIRST_BIT 92 select GENERIC_IRQ_PROBE 93 select GENERIC_PENDING_IRQ if SMP 94 select GENERIC_IRQ_SHOW 95 select GENERIC_CLOCKEVENTS_MIN_ADJUST 96 select IRQ_FORCED_THREADING 97 select HAVE_BPF_JIT if X86_64 98 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 99 select CLKEVT_I8253 100 select ARCH_HAVE_NMI_SAFE_CMPXCHG 101 select GENERIC_IOMAP 102 select DCACHE_WORD_ACCESS 103 select GENERIC_SMP_IDLE_THREAD 104 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 105 select HAVE_ARCH_SECCOMP_FILTER 106 select BUILDTIME_EXTABLE_SORT 107 select GENERIC_CMOS_UPDATE 108 select HAVE_ARCH_SOFT_DIRTY if X86_64 109 select CLOCKSOURCE_WATCHDOG 110 select GENERIC_CLOCKEVENTS 111 select ARCH_CLOCKSOURCE_DATA 112 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 113 select GENERIC_TIME_VSYSCALL 114 select KTIME_SCALAR if X86_32 115 select GENERIC_STRNCPY_FROM_USER 116 select GENERIC_STRNLEN_USER 117 select HAVE_CONTEXT_TRACKING if X86_64 118 select HAVE_IRQ_TIME_ACCOUNTING 119 select VIRT_TO_BUS 120 select MODULES_USE_ELF_REL if X86_32 121 select MODULES_USE_ELF_RELA if X86_64 122 select CLONE_BACKWARDS if X86_32 123 select ARCH_USE_BUILTIN_BSWAP 124 select ARCH_USE_QUEUE_RWLOCK 125 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 126 select OLD_SIGACTION if X86_32 127 select COMPAT_OLD_SIGACTION if IA32_EMULATION 128 select RTC_LIB 129 select HAVE_DEBUG_STACKOVERFLOW 130 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 131 select HAVE_CC_STACKPROTECTOR 132 select GENERIC_CPU_AUTOPROBE 133 select HAVE_ARCH_AUDITSYSCALL 134 select ARCH_SUPPORTS_ATOMIC_RMW 135 136config INSTRUCTION_DECODER 137 def_bool y 138 depends on KPROBES || PERF_EVENTS || UPROBES 139 140config OUTPUT_FORMAT 141 string 142 default "elf32-i386" if X86_32 143 default "elf64-x86-64" if X86_64 144 145config ARCH_DEFCONFIG 146 string 147 default "arch/x86/configs/i386_defconfig" if X86_32 148 default "arch/x86/configs/x86_64_defconfig" if X86_64 149 150config LOCKDEP_SUPPORT 151 def_bool y 152 153config STACKTRACE_SUPPORT 154 def_bool y 155 156config HAVE_LATENCYTOP_SUPPORT 157 def_bool y 158 159config MMU 160 def_bool y 161 162config SBUS 163 bool 164 165config NEED_DMA_MAP_STATE 166 def_bool y 167 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG 168 169config NEED_SG_DMA_LENGTH 170 def_bool y 171 172config GENERIC_ISA_DMA 173 def_bool y 174 depends on ISA_DMA_API 175 176config GENERIC_BUG 177 def_bool y 178 depends on BUG 179 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 180 181config GENERIC_BUG_RELATIVE_POINTERS 182 bool 183 184config GENERIC_HWEIGHT 185 def_bool y 186 187config ARCH_MAY_HAVE_PC_FDC 188 def_bool y 189 depends on ISA_DMA_API 190 191config RWSEM_XCHGADD_ALGORITHM 192 def_bool y 193 194config GENERIC_CALIBRATE_DELAY 195 def_bool y 196 197config ARCH_HAS_CPU_RELAX 198 def_bool y 199 200config ARCH_HAS_CACHE_LINE_SIZE 201 def_bool y 202 203config HAVE_SETUP_PER_CPU_AREA 204 def_bool y 205 206config NEED_PER_CPU_EMBED_FIRST_CHUNK 207 def_bool y 208 209config NEED_PER_CPU_PAGE_FIRST_CHUNK 210 def_bool y 211 212config ARCH_HIBERNATION_POSSIBLE 213 def_bool y 214 215config ARCH_SUSPEND_POSSIBLE 216 def_bool y 217 218config ARCH_WANT_HUGE_PMD_SHARE 219 def_bool y 220 221config ARCH_WANT_GENERAL_HUGETLB 222 def_bool y 223 224config ZONE_DMA32 225 bool 226 default X86_64 227 228config AUDIT_ARCH 229 bool 230 default X86_64 231 232config ARCH_SUPPORTS_OPTIMIZED_INLINING 233 def_bool y 234 235config ARCH_SUPPORTS_DEBUG_PAGEALLOC 236 def_bool y 237 238config HAVE_INTEL_TXT 239 def_bool y 240 depends on INTEL_IOMMU && ACPI 241 242config X86_32_SMP 243 def_bool y 244 depends on X86_32 && SMP 245 246config X86_64_SMP 247 def_bool y 248 depends on X86_64 && SMP 249 250config X86_HT 251 def_bool y 252 depends on SMP 253 254config X86_32_LAZY_GS 255 def_bool y 256 depends on X86_32 && !CC_STACKPROTECTOR 257 258config ARCH_HWEIGHT_CFLAGS 259 string 260 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 261 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 262 263config ARCH_SUPPORTS_UPROBES 264 def_bool y 265 266config FIX_EARLYCON_MEM 267 def_bool y 268 269source "init/Kconfig" 270source "kernel/Kconfig.freezer" 271 272menu "Processor type and features" 273 274config ZONE_DMA 275 bool "DMA memory allocation support" if EXPERT 276 default y 277 help 278 DMA memory allocation support allows devices with less than 32-bit 279 addressing to allocate within the first 16MB of address space. 280 Disable if no such devices will be used. 281 282 If unsure, say Y. 283 284config SMP 285 bool "Symmetric multi-processing support" 286 ---help--- 287 This enables support for systems with more than one CPU. If you have 288 a system with only one CPU, say N. If you have a system with more 289 than one CPU, say Y. 290 291 If you say N here, the kernel will run on uni- and multiprocessor 292 machines, but will use only one CPU of a multiprocessor machine. If 293 you say Y here, the kernel will run on many, but not all, 294 uniprocessor machines. On a uniprocessor machine, the kernel 295 will run faster if you say N here. 296 297 Note that if you say Y here and choose architecture "586" or 298 "Pentium" under "Processor family", the kernel will not work on 486 299 architectures. Similarly, multiprocessor kernels for the "PPro" 300 architecture may not work on all Pentium based boards. 301 302 People using multiprocessor machines who say Y here should also say 303 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 304 Management" code will be disabled if you say Y here. 305 306 See also <file:Documentation/x86/i386/IO-APIC.txt>, 307 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 308 <http://www.tldp.org/docs.html#howto>. 309 310 If you don't know what to do here, say N. 311 312config X86_X2APIC 313 bool "Support x2apic" 314 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 315 ---help--- 316 This enables x2apic support on CPUs that have this feature. 317 318 This allows 32-bit apic IDs (so it can support very large systems), 319 and accesses the local apic via MSRs not via mmio. 320 321 If you don't know what to do here, say N. 322 323config X86_MPPARSE 324 bool "Enable MPS table" if ACPI || SFI 325 default y 326 depends on X86_LOCAL_APIC 327 ---help--- 328 For old smp systems that do not have proper acpi support. Newer systems 329 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 330 331config X86_BIGSMP 332 bool "Support for big SMP systems with more than 8 CPUs" 333 depends on X86_32 && SMP 334 ---help--- 335 This option is needed for the systems that have more than 8 CPUs 336 337config GOLDFISH 338 def_bool y 339 depends on X86_GOLDFISH 340 341if X86_32 342config X86_EXTENDED_PLATFORM 343 bool "Support for extended (non-PC) x86 platforms" 344 default y 345 ---help--- 346 If you disable this option then the kernel will only support 347 standard PC platforms. (which covers the vast majority of 348 systems out there.) 349 350 If you enable this option then you'll be able to select support 351 for the following (non-PC) 32 bit x86 platforms: 352 Goldfish (Android emulator) 353 AMD Elan 354 RDC R-321x SoC 355 SGI 320/540 (Visual Workstation) 356 STA2X11-based (e.g. Northville) 357 Moorestown MID devices 358 359 If you have one of these systems, or if you want to build a 360 generic distribution kernel, say Y here - otherwise say N. 361endif 362 363if X86_64 364config X86_EXTENDED_PLATFORM 365 bool "Support for extended (non-PC) x86 platforms" 366 default y 367 ---help--- 368 If you disable this option then the kernel will only support 369 standard PC platforms. (which covers the vast majority of 370 systems out there.) 371 372 If you enable this option then you'll be able to select support 373 for the following (non-PC) 64 bit x86 platforms: 374 Numascale NumaChip 375 ScaleMP vSMP 376 SGI Ultraviolet 377 378 If you have one of these systems, or if you want to build a 379 generic distribution kernel, say Y here - otherwise say N. 380endif 381# This is an alphabetically sorted list of 64 bit extended platforms 382# Please maintain the alphabetic order if and when there are additions 383config X86_NUMACHIP 384 bool "Numascale NumaChip" 385 depends on X86_64 386 depends on X86_EXTENDED_PLATFORM 387 depends on NUMA 388 depends on SMP 389 depends on X86_X2APIC 390 depends on PCI_MMCONFIG 391 ---help--- 392 Adds support for Numascale NumaChip large-SMP systems. Needed to 393 enable more than ~168 cores. 394 If you don't have one of these, you should say N here. 395 396config X86_VSMP 397 bool "ScaleMP vSMP" 398 select HYPERVISOR_GUEST 399 select PARAVIRT 400 depends on X86_64 && PCI 401 depends on X86_EXTENDED_PLATFORM 402 depends on SMP 403 ---help--- 404 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 405 supposed to run on these EM64T-based machines. Only choose this option 406 if you have one of these machines. 407 408config X86_UV 409 bool "SGI Ultraviolet" 410 depends on X86_64 411 depends on X86_EXTENDED_PLATFORM 412 depends on NUMA 413 depends on X86_X2APIC 414 ---help--- 415 This option is needed in order to support SGI Ultraviolet systems. 416 If you don't have one of these, you should say N here. 417 418# Following is an alphabetically sorted list of 32 bit extended platforms 419# Please maintain the alphabetic order if and when there are additions 420 421config X86_GOLDFISH 422 bool "Goldfish (Virtual Platform)" 423 depends on X86_EXTENDED_PLATFORM 424 ---help--- 425 Enable support for the Goldfish virtual platform used primarily 426 for Android development. Unless you are building for the Android 427 Goldfish emulator say N here. 428 429config X86_INTEL_CE 430 bool "CE4100 TV platform" 431 depends on PCI 432 depends on PCI_GODIRECT 433 depends on X86_32 434 depends on X86_EXTENDED_PLATFORM 435 select X86_REBOOTFIXUPS 436 select OF 437 select OF_EARLY_FLATTREE 438 select IRQ_DOMAIN 439 ---help--- 440 Select for the Intel CE media processor (CE4100) SOC. 441 This option compiles in support for the CE4100 SOC for settop 442 boxes and media devices. 443 444config X86_INTEL_MID 445 bool "Intel MID platform support" 446 depends on X86_32 447 depends on X86_EXTENDED_PLATFORM 448 depends on X86_PLATFORM_DEVICES 449 depends on PCI 450 depends on PCI_GOANY 451 depends on X86_IO_APIC 452 select SFI 453 select I2C 454 select DW_APB_TIMER 455 select APB_TIMER 456 select INTEL_SCU_IPC 457 select MFD_INTEL_MSIC 458 ---help--- 459 Select to build a kernel capable of supporting Intel MID (Mobile 460 Internet Device) platform systems which do not have the PCI legacy 461 interfaces. If you are building for a PC class system say N here. 462 463 Intel MID platforms are based on an Intel processor and chipset which 464 consume less power than most of the x86 derivatives. 465 466config X86_INTEL_LPSS 467 bool "Intel Low Power Subsystem Support" 468 depends on ACPI 469 select COMMON_CLK 470 select PINCTRL 471 ---help--- 472 Select to build support for Intel Low Power Subsystem such as 473 found on Intel Lynxpoint PCH. Selecting this option enables 474 things like clock tree (common clock framework) and pincontrol 475 which are needed by the LPSS peripheral drivers. 476 477config X86_RDC321X 478 bool "RDC R-321x SoC" 479 depends on X86_32 480 depends on X86_EXTENDED_PLATFORM 481 select M486 482 select X86_REBOOTFIXUPS 483 ---help--- 484 This option is needed for RDC R-321x system-on-chip, also known 485 as R-8610-(G). 486 If you don't have one of these chips, you should say N here. 487 488config X86_32_NON_STANDARD 489 bool "Support non-standard 32-bit SMP architectures" 490 depends on X86_32 && SMP 491 depends on X86_EXTENDED_PLATFORM 492 ---help--- 493 This option compiles in the bigsmp and STA2X11 default 494 subarchitectures. It is intended for a generic binary 495 kernel. If you select them all, kernel will probe it one by 496 one and will fallback to default. 497 498# Alphabetically sorted list of Non standard 32 bit platforms 499 500config X86_SUPPORTS_MEMORY_FAILURE 501 def_bool y 502 # MCE code calls memory_failure(): 503 depends on X86_MCE 504 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 505 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 506 depends on X86_64 || !SPARSEMEM 507 select ARCH_SUPPORTS_MEMORY_FAILURE 508 509config STA2X11 510 bool "STA2X11 Companion Chip Support" 511 depends on X86_32_NON_STANDARD && PCI 512 select X86_DEV_DMA_OPS 513 select X86_DMA_REMAP 514 select SWIOTLB 515 select MFD_STA2X11 516 select ARCH_REQUIRE_GPIOLIB 517 default n 518 ---help--- 519 This adds support for boards based on the STA2X11 IO-Hub, 520 a.k.a. "ConneXt". The chip is used in place of the standard 521 PC chipset, so all "standard" peripherals are missing. If this 522 option is selected the kernel will still be able to boot on 523 standard PC machines. 524 525config X86_32_IRIS 526 tristate "Eurobraille/Iris poweroff module" 527 depends on X86_32 528 ---help--- 529 The Iris machines from EuroBraille do not have APM or ACPI support 530 to shut themselves down properly. A special I/O sequence is 531 needed to do so, which is what this module does at 532 kernel shutdown. 533 534 This is only for Iris machines from EuroBraille. 535 536 If unused, say N. 537 538config SCHED_OMIT_FRAME_POINTER 539 def_bool y 540 prompt "Single-depth WCHAN output" 541 depends on X86 542 ---help--- 543 Calculate simpler /proc/<PID>/wchan values. If this option 544 is disabled then wchan values will recurse back to the 545 caller function. This provides more accurate wchan values, 546 at the expense of slightly more scheduling overhead. 547 548 If in doubt, say "Y". 549 550menuconfig HYPERVISOR_GUEST 551 bool "Linux guest support" 552 ---help--- 553 Say Y here to enable options for running Linux under various hyper- 554 visors. This option enables basic hypervisor detection and platform 555 setup. 556 557 If you say N, all options in this submenu will be skipped and 558 disabled, and Linux guest support won't be built in. 559 560if HYPERVISOR_GUEST 561 562config PARAVIRT 563 bool "Enable paravirtualization code" 564 ---help--- 565 This changes the kernel so it can modify itself when it is run 566 under a hypervisor, potentially improving performance significantly 567 over full virtualization. However, when run without a hypervisor 568 the kernel is theoretically slower and slightly larger. 569 570config PARAVIRT_DEBUG 571 bool "paravirt-ops debugging" 572 depends on PARAVIRT && DEBUG_KERNEL 573 ---help--- 574 Enable to debug paravirt_ops internals. Specifically, BUG if 575 a paravirt_op is missing when it is called. 576 577config PARAVIRT_SPINLOCKS 578 bool "Paravirtualization layer for spinlocks" 579 depends on PARAVIRT && SMP 580 select UNINLINE_SPIN_UNLOCK 581 ---help--- 582 Paravirtualized spinlocks allow a pvops backend to replace the 583 spinlock implementation with something virtualization-friendly 584 (for example, block the virtual CPU rather than spinning). 585 586 It has a minimal impact on native kernels and gives a nice performance 587 benefit on paravirtualized KVM / Xen kernels. 588 589 If you are unsure how to answer this question, answer Y. 590 591source "arch/x86/xen/Kconfig" 592 593config KVM_GUEST 594 bool "KVM Guest support (including kvmclock)" 595 depends on PARAVIRT 596 select PARAVIRT_CLOCK 597 default y 598 ---help--- 599 This option enables various optimizations for running under the KVM 600 hypervisor. It includes a paravirtualized clock, so that instead 601 of relying on a PIT (or probably other) emulation by the 602 underlying device model, the host provides the guest with 603 timing infrastructure such as time of day, and system time 604 605config KVM_DEBUG_FS 606 bool "Enable debug information for KVM Guests in debugfs" 607 depends on KVM_GUEST && DEBUG_FS 608 default n 609 ---help--- 610 This option enables collection of various statistics for KVM guest. 611 Statistics are displayed in debugfs filesystem. Enabling this option 612 may incur significant overhead. 613 614source "arch/x86/lguest/Kconfig" 615 616config PARAVIRT_TIME_ACCOUNTING 617 bool "Paravirtual steal time accounting" 618 depends on PARAVIRT 619 default n 620 ---help--- 621 Select this option to enable fine granularity task steal time 622 accounting. Time spent executing other tasks in parallel with 623 the current vCPU is discounted from the vCPU power. To account for 624 that, there can be a small performance impact. 625 626 If in doubt, say N here. 627 628config PARAVIRT_CLOCK 629 bool 630 631endif #HYPERVISOR_GUEST 632 633config NO_BOOTMEM 634 def_bool y 635 636config MEMTEST 637 bool "Memtest" 638 ---help--- 639 This option adds a kernel parameter 'memtest', which allows memtest 640 to be set. 641 memtest=0, mean disabled; -- default 642 memtest=1, mean do 1 test pattern; 643 ... 644 memtest=4, mean do 4 test patterns. 645 If you are unsure how to answer this question, answer N. 646 647source "arch/x86/Kconfig.cpu" 648 649config HPET_TIMER 650 def_bool X86_64 651 prompt "HPET Timer Support" if X86_32 652 ---help--- 653 Use the IA-PC HPET (High Precision Event Timer) to manage 654 time in preference to the PIT and RTC, if a HPET is 655 present. 656 HPET is the next generation timer replacing legacy 8254s. 657 The HPET provides a stable time base on SMP 658 systems, unlike the TSC, but it is more expensive to access, 659 as it is off-chip. You can find the HPET spec at 660 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 661 662 You can safely choose Y here. However, HPET will only be 663 activated if the platform and the BIOS support this feature. 664 Otherwise the 8254 will be used for timing services. 665 666 Choose N to continue using the legacy 8254 timer. 667 668config HPET_EMULATE_RTC 669 def_bool y 670 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 671 672config APB_TIMER 673 def_bool y if X86_INTEL_MID 674 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 675 select DW_APB_TIMER 676 depends on X86_INTEL_MID && SFI 677 help 678 APB timer is the replacement for 8254, HPET on X86 MID platforms. 679 The APBT provides a stable time base on SMP 680 systems, unlike the TSC, but it is more expensive to access, 681 as it is off-chip. APB timers are always running regardless of CPU 682 C states, they are used as per CPU clockevent device when possible. 683 684# Mark as expert because too many people got it wrong. 685# The code disables itself when not needed. 686config DMI 687 default y 688 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 689 bool "Enable DMI scanning" if EXPERT 690 ---help--- 691 Enabled scanning of DMI to identify machine quirks. Say Y 692 here unless you have verified that your setup is not 693 affected by entries in the DMI blacklist. Required by PNP 694 BIOS code. 695 696config GART_IOMMU 697 bool "Old AMD GART IOMMU support" 698 select SWIOTLB 699 depends on X86_64 && PCI && AMD_NB 700 ---help--- 701 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 702 GART based hardware IOMMUs. 703 704 The GART supports full DMA access for devices with 32-bit access 705 limitations, on systems with more than 3 GB. This is usually needed 706 for USB, sound, many IDE/SATA chipsets and some other devices. 707 708 Newer systems typically have a modern AMD IOMMU, supported via 709 the CONFIG_AMD_IOMMU=y config option. 710 711 In normal configurations this driver is only active when needed: 712 there's more than 3 GB of memory and the system contains a 713 32-bit limited device. 714 715 If unsure, say Y. 716 717config CALGARY_IOMMU 718 bool "IBM Calgary IOMMU support" 719 select SWIOTLB 720 depends on X86_64 && PCI 721 ---help--- 722 Support for hardware IOMMUs in IBM's xSeries x366 and x460 723 systems. Needed to run systems with more than 3GB of memory 724 properly with 32-bit PCI devices that do not support DAC 725 (Double Address Cycle). Calgary also supports bus level 726 isolation, where all DMAs pass through the IOMMU. This 727 prevents them from going anywhere except their intended 728 destination. This catches hard-to-find kernel bugs and 729 mis-behaving drivers and devices that do not use the DMA-API 730 properly to set up their DMA buffers. The IOMMU can be 731 turned off at boot time with the iommu=off parameter. 732 Normally the kernel will make the right choice by itself. 733 If unsure, say Y. 734 735config CALGARY_IOMMU_ENABLED_BY_DEFAULT 736 def_bool y 737 prompt "Should Calgary be enabled by default?" 738 depends on CALGARY_IOMMU 739 ---help--- 740 Should Calgary be enabled by default? if you choose 'y', Calgary 741 will be used (if it exists). If you choose 'n', Calgary will not be 742 used even if it exists. If you choose 'n' and would like to use 743 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 744 If unsure, say Y. 745 746# need this always selected by IOMMU for the VIA workaround 747config SWIOTLB 748 def_bool y if X86_64 749 ---help--- 750 Support for software bounce buffers used on x86-64 systems 751 which don't have a hardware IOMMU. Using this PCI devices 752 which can only access 32-bits of memory can be used on systems 753 with more than 3 GB of memory. 754 If unsure, say Y. 755 756config IOMMU_HELPER 757 def_bool y 758 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 759 760config MAXSMP 761 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 762 depends on X86_64 && SMP && DEBUG_KERNEL 763 select CPUMASK_OFFSTACK 764 ---help--- 765 Enable maximum number of CPUS and NUMA Nodes for this architecture. 766 If unsure, say N. 767 768config NR_CPUS 769 int "Maximum number of CPUs" if SMP && !MAXSMP 770 range 2 8 if SMP && X86_32 && !X86_BIGSMP 771 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 772 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 773 default "1" if !SMP 774 default "8192" if MAXSMP 775 default "32" if SMP && X86_BIGSMP 776 default "8" if SMP 777 ---help--- 778 This allows you to specify the maximum number of CPUs which this 779 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 780 supported value is 4096, otherwise the maximum value is 512. The 781 minimum value which makes sense is 2. 782 783 This is purely to save memory - each supported CPU adds 784 approximately eight kilobytes to the kernel image. 785 786config SCHED_SMT 787 bool "SMT (Hyperthreading) scheduler support" 788 depends on X86_HT 789 ---help--- 790 SMT scheduler support improves the CPU scheduler's decision making 791 when dealing with Intel Pentium 4 chips with HyperThreading at a 792 cost of slightly increased overhead in some places. If unsure say 793 N here. 794 795config SCHED_MC 796 def_bool y 797 prompt "Multi-core scheduler support" 798 depends on X86_HT 799 ---help--- 800 Multi-core scheduler support improves the CPU scheduler's decision 801 making when dealing with multi-core CPU chips at a cost of slightly 802 increased overhead in some places. If unsure say N here. 803 804source "kernel/Kconfig.preempt" 805 806config X86_UP_APIC 807 bool "Local APIC support on uniprocessors" 808 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI 809 ---help--- 810 A local APIC (Advanced Programmable Interrupt Controller) is an 811 integrated interrupt controller in the CPU. If you have a single-CPU 812 system which has a processor with a local APIC, you can say Y here to 813 enable and use it. If you say Y here even though your machine doesn't 814 have a local APIC, then the kernel will still run with no slowdown at 815 all. The local APIC supports CPU-generated self-interrupts (timer, 816 performance counters), and the NMI watchdog which detects hard 817 lockups. 818 819config X86_UP_IOAPIC 820 bool "IO-APIC support on uniprocessors" 821 depends on X86_UP_APIC 822 ---help--- 823 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 824 SMP-capable replacement for PC-style interrupt controllers. Most 825 SMP systems and many recent uniprocessor systems have one. 826 827 If you have a single-CPU system with an IO-APIC, you can say Y here 828 to use it. If you say Y here even though your machine doesn't have 829 an IO-APIC, then the kernel will still run with no slowdown at all. 830 831config X86_LOCAL_APIC 832 def_bool y 833 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 834 835config X86_IO_APIC 836 def_bool y 837 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI 838 select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ 839 840config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 841 bool "Reroute for broken boot IRQs" 842 depends on X86_IO_APIC 843 ---help--- 844 This option enables a workaround that fixes a source of 845 spurious interrupts. This is recommended when threaded 846 interrupt handling is used on systems where the generation of 847 superfluous "boot interrupts" cannot be disabled. 848 849 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 850 entry in the chipset's IO-APIC is masked (as, e.g. the RT 851 kernel does during interrupt handling). On chipsets where this 852 boot IRQ generation cannot be disabled, this workaround keeps 853 the original IRQ line masked so that only the equivalent "boot 854 IRQ" is delivered to the CPUs. The workaround also tells the 855 kernel to set up the IRQ handler on the boot IRQ line. In this 856 way only one interrupt is delivered to the kernel. Otherwise 857 the spurious second interrupt may cause the kernel to bring 858 down (vital) interrupt lines. 859 860 Only affects "broken" chipsets. Interrupt sharing may be 861 increased on these systems. 862 863config X86_MCE 864 bool "Machine Check / overheating reporting" 865 default y 866 ---help--- 867 Machine Check support allows the processor to notify the 868 kernel if it detects a problem (e.g. overheating, data corruption). 869 The action the kernel takes depends on the severity of the problem, 870 ranging from warning messages to halting the machine. 871 872config X86_MCE_INTEL 873 def_bool y 874 prompt "Intel MCE features" 875 depends on X86_MCE && X86_LOCAL_APIC 876 ---help--- 877 Additional support for intel specific MCE features such as 878 the thermal monitor. 879 880config X86_MCE_AMD 881 def_bool y 882 prompt "AMD MCE features" 883 depends on X86_MCE && X86_LOCAL_APIC 884 ---help--- 885 Additional support for AMD specific MCE features such as 886 the DRAM Error Threshold. 887 888config X86_ANCIENT_MCE 889 bool "Support for old Pentium 5 / WinChip machine checks" 890 depends on X86_32 && X86_MCE 891 ---help--- 892 Include support for machine check handling on old Pentium 5 or WinChip 893 systems. These typically need to be enabled explicitly on the command 894 line. 895 896config X86_MCE_THRESHOLD 897 depends on X86_MCE_AMD || X86_MCE_INTEL 898 def_bool y 899 900config X86_MCE_INJECT 901 depends on X86_MCE 902 tristate "Machine check injector support" 903 ---help--- 904 Provide support for injecting machine checks for testing purposes. 905 If you don't know what a machine check is and you don't do kernel 906 QA it is safe to say n. 907 908config X86_THERMAL_VECTOR 909 def_bool y 910 depends on X86_MCE_INTEL 911 912config VM86 913 bool "Enable VM86 support" if EXPERT 914 default y 915 depends on X86_32 916 ---help--- 917 This option is required by programs like DOSEMU to run 918 16-bit real mode legacy code on x86 processors. It also may 919 be needed by software like XFree86 to initialize some video 920 cards via BIOS. Disabling this option saves about 6K. 921 922config X86_16BIT 923 bool "Enable support for 16-bit segments" if EXPERT 924 default y 925 ---help--- 926 This option is required by programs like Wine to run 16-bit 927 protected mode legacy code on x86 processors. Disabling 928 this option saves about 300 bytes on i386, or around 6K text 929 plus 16K runtime memory on x86-64, 930 931config X86_ESPFIX32 932 def_bool y 933 depends on X86_16BIT && X86_32 934 935config X86_ESPFIX64 936 def_bool y 937 depends on X86_16BIT && X86_64 938 939config TOSHIBA 940 tristate "Toshiba Laptop support" 941 depends on X86_32 942 ---help--- 943 This adds a driver to safely access the System Management Mode of 944 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 945 not work on models with a Phoenix BIOS. The System Management Mode 946 is used to set the BIOS and power saving options on Toshiba portables. 947 948 For information on utilities to make use of this driver see the 949 Toshiba Linux utilities web site at: 950 <http://www.buzzard.org.uk/toshiba/>. 951 952 Say Y if you intend to run this kernel on a Toshiba portable. 953 Say N otherwise. 954 955config I8K 956 tristate "Dell laptop support" 957 select HWMON 958 ---help--- 959 This adds a driver to safely access the System Management Mode 960 of the CPU on the Dell Inspiron 8000. The System Management Mode 961 is used to read cpu temperature and cooling fan status and to 962 control the fans on the I8K portables. 963 964 This driver has been tested only on the Inspiron 8000 but it may 965 also work with other Dell laptops. You can force loading on other 966 models by passing the parameter `force=1' to the module. Use at 967 your own risk. 968 969 For information on utilities to make use of this driver see the 970 I8K Linux utilities web site at: 971 <http://people.debian.org/~dz/i8k/> 972 973 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 974 Say N otherwise. 975 976config X86_REBOOTFIXUPS 977 bool "Enable X86 board specific fixups for reboot" 978 depends on X86_32 979 ---help--- 980 This enables chipset and/or board specific fixups to be done 981 in order to get reboot to work correctly. This is only needed on 982 some combinations of hardware and BIOS. The symptom, for which 983 this config is intended, is when reboot ends with a stalled/hung 984 system. 985 986 Currently, the only fixup is for the Geode machines using 987 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 988 989 Say Y if you want to enable the fixup. Currently, it's safe to 990 enable this option even if you don't need it. 991 Say N otherwise. 992 993config MICROCODE 994 tristate "CPU microcode loading support" 995 depends on CPU_SUP_AMD || CPU_SUP_INTEL 996 select FW_LOADER 997 ---help--- 998 999 If you say Y here, you will be able to update the microcode on 1000 certain Intel and AMD processors. The Intel support is for the 1001 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1002 Xeon etc. The AMD support is for families 0x10 and later. You will 1003 obviously need the actual microcode binary data itself which is not 1004 shipped with the Linux kernel. 1005 1006 This option selects the general module only, you need to select 1007 at least one vendor specific module as well. 1008 1009 To compile this driver as a module, choose M here: the module 1010 will be called microcode. 1011 1012config MICROCODE_INTEL 1013 bool "Intel microcode loading support" 1014 depends on MICROCODE 1015 default MICROCODE 1016 select FW_LOADER 1017 ---help--- 1018 This options enables microcode patch loading support for Intel 1019 processors. 1020 1021 For the current Intel microcode data package go to 1022 <https://downloadcenter.intel.com> and search for 1023 'Linux Processor Microcode Data File'. 1024 1025config MICROCODE_AMD 1026 bool "AMD microcode loading support" 1027 depends on MICROCODE 1028 select FW_LOADER 1029 ---help--- 1030 If you select this option, microcode patch loading support for AMD 1031 processors will be enabled. 1032 1033config MICROCODE_OLD_INTERFACE 1034 def_bool y 1035 depends on MICROCODE 1036 1037config MICROCODE_INTEL_EARLY 1038 def_bool n 1039 1040config MICROCODE_AMD_EARLY 1041 def_bool n 1042 1043config MICROCODE_EARLY 1044 bool "Early load microcode" 1045 depends on MICROCODE=y && BLK_DEV_INITRD 1046 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1047 select MICROCODE_AMD_EARLY if MICROCODE_AMD 1048 default y 1049 help 1050 This option provides functionality to read additional microcode data 1051 at the beginning of initrd image. The data tells kernel to load 1052 microcode to CPU's as early as possible. No functional change if no 1053 microcode data is glued to the initrd, therefore it's safe to say Y. 1054 1055config X86_MSR 1056 tristate "/dev/cpu/*/msr - Model-specific register support" 1057 ---help--- 1058 This device gives privileged processes access to the x86 1059 Model-Specific Registers (MSRs). It is a character device with 1060 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1061 MSR accesses are directed to a specific CPU on multi-processor 1062 systems. 1063 1064config X86_CPUID 1065 tristate "/dev/cpu/*/cpuid - CPU information support" 1066 ---help--- 1067 This device gives processes access to the x86 CPUID instruction to 1068 be executed on a specific processor. It is a character device 1069 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1070 /dev/cpu/31/cpuid. 1071 1072choice 1073 prompt "High Memory Support" 1074 default HIGHMEM4G 1075 depends on X86_32 1076 1077config NOHIGHMEM 1078 bool "off" 1079 ---help--- 1080 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1081 However, the address space of 32-bit x86 processors is only 4 1082 Gigabytes large. That means that, if you have a large amount of 1083 physical memory, not all of it can be "permanently mapped" by the 1084 kernel. The physical memory that's not permanently mapped is called 1085 "high memory". 1086 1087 If you are compiling a kernel which will never run on a machine with 1088 more than 1 Gigabyte total physical RAM, answer "off" here (default 1089 choice and suitable for most users). This will result in a "3GB/1GB" 1090 split: 3GB are mapped so that each process sees a 3GB virtual memory 1091 space and the remaining part of the 4GB virtual memory space is used 1092 by the kernel to permanently map as much physical memory as 1093 possible. 1094 1095 If the machine has between 1 and 4 Gigabytes physical RAM, then 1096 answer "4GB" here. 1097 1098 If more than 4 Gigabytes is used then answer "64GB" here. This 1099 selection turns Intel PAE (Physical Address Extension) mode on. 1100 PAE implements 3-level paging on IA32 processors. PAE is fully 1101 supported by Linux, PAE mode is implemented on all recent Intel 1102 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1103 then the kernel will not boot on CPUs that don't support PAE! 1104 1105 The actual amount of total physical memory will either be 1106 auto detected or can be forced by using a kernel command line option 1107 such as "mem=256M". (Try "man bootparam" or see the documentation of 1108 your boot loader (lilo or loadlin) about how to pass options to the 1109 kernel at boot time.) 1110 1111 If unsure, say "off". 1112 1113config HIGHMEM4G 1114 bool "4GB" 1115 ---help--- 1116 Select this if you have a 32-bit processor and between 1 and 4 1117 gigabytes of physical RAM. 1118 1119config HIGHMEM64G 1120 bool "64GB" 1121 depends on !M486 1122 select X86_PAE 1123 ---help--- 1124 Select this if you have a 32-bit processor and more than 4 1125 gigabytes of physical RAM. 1126 1127endchoice 1128 1129choice 1130 prompt "Memory split" if EXPERT 1131 default VMSPLIT_3G 1132 depends on X86_32 1133 ---help--- 1134 Select the desired split between kernel and user memory. 1135 1136 If the address range available to the kernel is less than the 1137 physical memory installed, the remaining memory will be available 1138 as "high memory". Accessing high memory is a little more costly 1139 than low memory, as it needs to be mapped into the kernel first. 1140 Note that increasing the kernel address space limits the range 1141 available to user programs, making the address space there 1142 tighter. Selecting anything other than the default 3G/1G split 1143 will also likely make your kernel incompatible with binary-only 1144 kernel modules. 1145 1146 If you are not absolutely sure what you are doing, leave this 1147 option alone! 1148 1149 config VMSPLIT_3G 1150 bool "3G/1G user/kernel split" 1151 config VMSPLIT_3G_OPT 1152 depends on !X86_PAE 1153 bool "3G/1G user/kernel split (for full 1G low memory)" 1154 config VMSPLIT_2G 1155 bool "2G/2G user/kernel split" 1156 config VMSPLIT_2G_OPT 1157 depends on !X86_PAE 1158 bool "2G/2G user/kernel split (for full 2G low memory)" 1159 config VMSPLIT_1G 1160 bool "1G/3G user/kernel split" 1161endchoice 1162 1163config PAGE_OFFSET 1164 hex 1165 default 0xB0000000 if VMSPLIT_3G_OPT 1166 default 0x80000000 if VMSPLIT_2G 1167 default 0x78000000 if VMSPLIT_2G_OPT 1168 default 0x40000000 if VMSPLIT_1G 1169 default 0xC0000000 1170 depends on X86_32 1171 1172config HIGHMEM 1173 def_bool y 1174 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1175 1176config X86_PAE 1177 bool "PAE (Physical Address Extension) Support" 1178 depends on X86_32 && !HIGHMEM4G 1179 ---help--- 1180 PAE is required for NX support, and furthermore enables 1181 larger swapspace support for non-overcommit purposes. It 1182 has the cost of more pagetable lookup overhead, and also 1183 consumes more pagetable space per process. 1184 1185config ARCH_PHYS_ADDR_T_64BIT 1186 def_bool y 1187 depends on X86_64 || X86_PAE 1188 1189config ARCH_DMA_ADDR_T_64BIT 1190 def_bool y 1191 depends on X86_64 || HIGHMEM64G 1192 1193config DIRECT_GBPAGES 1194 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1195 default y 1196 depends on X86_64 1197 ---help--- 1198 Allow the kernel linear mapping to use 1GB pages on CPUs that 1199 support it. This can improve the kernel's performance a tiny bit by 1200 reducing TLB pressure. If in doubt, say "Y". 1201 1202# Common NUMA Features 1203config NUMA 1204 bool "Numa Memory Allocation and Scheduler Support" 1205 depends on SMP 1206 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1207 default y if X86_BIGSMP 1208 ---help--- 1209 Enable NUMA (Non Uniform Memory Access) support. 1210 1211 The kernel will try to allocate memory used by a CPU on the 1212 local memory controller of the CPU and add some more 1213 NUMA awareness to the kernel. 1214 1215 For 64-bit this is recommended if the system is Intel Core i7 1216 (or later), AMD Opteron, or EM64T NUMA. 1217 1218 For 32-bit this is only needed if you boot a 32-bit 1219 kernel on a 64-bit NUMA platform. 1220 1221 Otherwise, you should say N. 1222 1223config AMD_NUMA 1224 def_bool y 1225 prompt "Old style AMD Opteron NUMA detection" 1226 depends on X86_64 && NUMA && PCI 1227 ---help--- 1228 Enable AMD NUMA node topology detection. You should say Y here if 1229 you have a multi processor AMD system. This uses an old method to 1230 read the NUMA configuration directly from the builtin Northbridge 1231 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1232 which also takes priority if both are compiled in. 1233 1234config X86_64_ACPI_NUMA 1235 def_bool y 1236 prompt "ACPI NUMA detection" 1237 depends on X86_64 && NUMA && ACPI && PCI 1238 select ACPI_NUMA 1239 ---help--- 1240 Enable ACPI SRAT based node topology detection. 1241 1242# Some NUMA nodes have memory ranges that span 1243# other nodes. Even though a pfn is valid and 1244# between a node's start and end pfns, it may not 1245# reside on that node. See memmap_init_zone() 1246# for details. 1247config NODES_SPAN_OTHER_NODES 1248 def_bool y 1249 depends on X86_64_ACPI_NUMA 1250 1251config NUMA_EMU 1252 bool "NUMA emulation" 1253 depends on NUMA 1254 ---help--- 1255 Enable NUMA emulation. A flat machine will be split 1256 into virtual nodes when booted with "numa=fake=N", where N is the 1257 number of nodes. This is only useful for debugging. 1258 1259config NODES_SHIFT 1260 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1261 range 1 10 1262 default "10" if MAXSMP 1263 default "6" if X86_64 1264 default "3" 1265 depends on NEED_MULTIPLE_NODES 1266 ---help--- 1267 Specify the maximum number of NUMA Nodes available on the target 1268 system. Increases memory reserved to accommodate various tables. 1269 1270config ARCH_HAVE_MEMORY_PRESENT 1271 def_bool y 1272 depends on X86_32 && DISCONTIGMEM 1273 1274config NEED_NODE_MEMMAP_SIZE 1275 def_bool y 1276 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1277 1278config ARCH_FLATMEM_ENABLE 1279 def_bool y 1280 depends on X86_32 && !NUMA 1281 1282config ARCH_DISCONTIGMEM_ENABLE 1283 def_bool y 1284 depends on NUMA && X86_32 1285 1286config ARCH_DISCONTIGMEM_DEFAULT 1287 def_bool y 1288 depends on NUMA && X86_32 1289 1290config ARCH_SPARSEMEM_ENABLE 1291 def_bool y 1292 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1293 select SPARSEMEM_STATIC if X86_32 1294 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1295 1296config ARCH_SPARSEMEM_DEFAULT 1297 def_bool y 1298 depends on X86_64 1299 1300config ARCH_SELECT_MEMORY_MODEL 1301 def_bool y 1302 depends on ARCH_SPARSEMEM_ENABLE 1303 1304config ARCH_MEMORY_PROBE 1305 bool "Enable sysfs memory/probe interface" 1306 depends on X86_64 && MEMORY_HOTPLUG 1307 help 1308 This option enables a sysfs memory/probe interface for testing. 1309 See Documentation/memory-hotplug.txt for more information. 1310 If you are unsure how to answer this question, answer N. 1311 1312config ARCH_PROC_KCORE_TEXT 1313 def_bool y 1314 depends on X86_64 && PROC_KCORE 1315 1316config ILLEGAL_POINTER_VALUE 1317 hex 1318 default 0 if X86_32 1319 default 0xdead000000000000 if X86_64 1320 1321source "mm/Kconfig" 1322 1323config HIGHPTE 1324 bool "Allocate 3rd-level pagetables from highmem" 1325 depends on HIGHMEM 1326 ---help--- 1327 The VM uses one page table entry for each page of physical memory. 1328 For systems with a lot of RAM, this can be wasteful of precious 1329 low memory. Setting this option will put user-space page table 1330 entries in high memory. 1331 1332config X86_CHECK_BIOS_CORRUPTION 1333 bool "Check for low memory corruption" 1334 ---help--- 1335 Periodically check for memory corruption in low memory, which 1336 is suspected to be caused by BIOS. Even when enabled in the 1337 configuration, it is disabled at runtime. Enable it by 1338 setting "memory_corruption_check=1" on the kernel command 1339 line. By default it scans the low 64k of memory every 60 1340 seconds; see the memory_corruption_check_size and 1341 memory_corruption_check_period parameters in 1342 Documentation/kernel-parameters.txt to adjust this. 1343 1344 When enabled with the default parameters, this option has 1345 almost no overhead, as it reserves a relatively small amount 1346 of memory and scans it infrequently. It both detects corruption 1347 and prevents it from affecting the running system. 1348 1349 It is, however, intended as a diagnostic tool; if repeatable 1350 BIOS-originated corruption always affects the same memory, 1351 you can use memmap= to prevent the kernel from using that 1352 memory. 1353 1354config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1355 bool "Set the default setting of memory_corruption_check" 1356 depends on X86_CHECK_BIOS_CORRUPTION 1357 default y 1358 ---help--- 1359 Set whether the default state of memory_corruption_check is 1360 on or off. 1361 1362config X86_RESERVE_LOW 1363 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1364 default 64 1365 range 4 640 1366 ---help--- 1367 Specify the amount of low memory to reserve for the BIOS. 1368 1369 The first page contains BIOS data structures that the kernel 1370 must not use, so that page must always be reserved. 1371 1372 By default we reserve the first 64K of physical RAM, as a 1373 number of BIOSes are known to corrupt that memory range 1374 during events such as suspend/resume or monitor cable 1375 insertion, so it must not be used by the kernel. 1376 1377 You can set this to 4 if you are absolutely sure that you 1378 trust the BIOS to get all its memory reservations and usages 1379 right. If you know your BIOS have problems beyond the 1380 default 64K area, you can set this to 640 to avoid using the 1381 entire low memory range. 1382 1383 If you have doubts about the BIOS (e.g. suspend/resume does 1384 not work or there's kernel crashes after certain hardware 1385 hotplug events) then you might want to enable 1386 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1387 typical corruption patterns. 1388 1389 Leave this to the default value of 64 if you are unsure. 1390 1391config MATH_EMULATION 1392 bool 1393 prompt "Math emulation" if X86_32 1394 ---help--- 1395 Linux can emulate a math coprocessor (used for floating point 1396 operations) if you don't have one. 486DX and Pentium processors have 1397 a math coprocessor built in, 486SX and 386 do not, unless you added 1398 a 487DX or 387, respectively. (The messages during boot time can 1399 give you some hints here ["man dmesg"].) Everyone needs either a 1400 coprocessor or this emulation. 1401 1402 If you don't have a math coprocessor, you need to say Y here; if you 1403 say Y here even though you have a coprocessor, the coprocessor will 1404 be used nevertheless. (This behavior can be changed with the kernel 1405 command line option "no387", which comes handy if your coprocessor 1406 is broken. Try "man bootparam" or see the documentation of your boot 1407 loader (lilo or loadlin) about how to pass options to the kernel at 1408 boot time.) This means that it is a good idea to say Y here if you 1409 intend to use this kernel on different machines. 1410 1411 More information about the internals of the Linux math coprocessor 1412 emulation can be found in <file:arch/x86/math-emu/README>. 1413 1414 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1415 kernel, it won't hurt. 1416 1417config MTRR 1418 def_bool y 1419 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1420 ---help--- 1421 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1422 the Memory Type Range Registers (MTRRs) may be used to control 1423 processor access to memory ranges. This is most useful if you have 1424 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1425 allows bus write transfers to be combined into a larger transfer 1426 before bursting over the PCI/AGP bus. This can increase performance 1427 of image write operations 2.5 times or more. Saying Y here creates a 1428 /proc/mtrr file which may be used to manipulate your processor's 1429 MTRRs. Typically the X server should use this. 1430 1431 This code has a reasonably generic interface so that similar 1432 control registers on other processors can be easily supported 1433 as well: 1434 1435 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1436 Registers (ARRs) which provide a similar functionality to MTRRs. For 1437 these, the ARRs are used to emulate the MTRRs. 1438 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1439 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1440 write-combining. All of these processors are supported by this code 1441 and it makes sense to say Y here if you have one of them. 1442 1443 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1444 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1445 can lead to all sorts of problems, so it's good to say Y here. 1446 1447 You can safely say Y even if your machine doesn't have MTRRs, you'll 1448 just add about 9 KB to your kernel. 1449 1450 See <file:Documentation/x86/mtrr.txt> for more information. 1451 1452config MTRR_SANITIZER 1453 def_bool y 1454 prompt "MTRR cleanup support" 1455 depends on MTRR 1456 ---help--- 1457 Convert MTRR layout from continuous to discrete, so X drivers can 1458 add writeback entries. 1459 1460 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1461 The largest mtrr entry size for a continuous block can be set with 1462 mtrr_chunk_size. 1463 1464 If unsure, say Y. 1465 1466config MTRR_SANITIZER_ENABLE_DEFAULT 1467 int "MTRR cleanup enable value (0-1)" 1468 range 0 1 1469 default "0" 1470 depends on MTRR_SANITIZER 1471 ---help--- 1472 Enable mtrr cleanup default value 1473 1474config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1475 int "MTRR cleanup spare reg num (0-7)" 1476 range 0 7 1477 default "1" 1478 depends on MTRR_SANITIZER 1479 ---help--- 1480 mtrr cleanup spare entries default, it can be changed via 1481 mtrr_spare_reg_nr=N on the kernel command line. 1482 1483config X86_PAT 1484 def_bool y 1485 prompt "x86 PAT support" if EXPERT 1486 depends on MTRR 1487 ---help--- 1488 Use PAT attributes to setup page level cache control. 1489 1490 PATs are the modern equivalents of MTRRs and are much more 1491 flexible than MTRRs. 1492 1493 Say N here if you see bootup problems (boot crash, boot hang, 1494 spontaneous reboots) or a non-working video driver. 1495 1496 If unsure, say Y. 1497 1498config ARCH_USES_PG_UNCACHED 1499 def_bool y 1500 depends on X86_PAT 1501 1502config ARCH_RANDOM 1503 def_bool y 1504 prompt "x86 architectural random number generator" if EXPERT 1505 ---help--- 1506 Enable the x86 architectural RDRAND instruction 1507 (Intel Bull Mountain technology) to generate random numbers. 1508 If supported, this is a high bandwidth, cryptographically 1509 secure hardware random number generator. 1510 1511config X86_SMAP 1512 def_bool y 1513 prompt "Supervisor Mode Access Prevention" if EXPERT 1514 ---help--- 1515 Supervisor Mode Access Prevention (SMAP) is a security 1516 feature in newer Intel processors. There is a small 1517 performance cost if this enabled and turned on; there is 1518 also a small increase in the kernel size if this is enabled. 1519 1520 If unsure, say Y. 1521 1522config EFI 1523 bool "EFI runtime service support" 1524 depends on ACPI 1525 select UCS2_STRING 1526 ---help--- 1527 This enables the kernel to use EFI runtime services that are 1528 available (such as the EFI variable services). 1529 1530 This option is only useful on systems that have EFI firmware. 1531 In addition, you should use the latest ELILO loader available 1532 at <http://elilo.sourceforge.net> in order to take advantage 1533 of EFI runtime services. However, even with this option, the 1534 resultant kernel should continue to boot on existing non-EFI 1535 platforms. 1536 1537config EFI_STUB 1538 bool "EFI stub support" 1539 depends on EFI 1540 ---help--- 1541 This kernel feature allows a bzImage to be loaded directly 1542 by EFI firmware without the use of a bootloader. 1543 1544 See Documentation/efi-stub.txt for more information. 1545 1546config EFI_MIXED 1547 bool "EFI mixed-mode support" 1548 depends on EFI_STUB && X86_64 1549 ---help--- 1550 Enabling this feature allows a 64-bit kernel to be booted 1551 on a 32-bit firmware, provided that your CPU supports 64-bit 1552 mode. 1553 1554 Note that it is not possible to boot a mixed-mode enabled 1555 kernel via the EFI boot stub - a bootloader that supports 1556 the EFI handover protocol must be used. 1557 1558 If unsure, say N. 1559 1560config SECCOMP 1561 def_bool y 1562 prompt "Enable seccomp to safely compute untrusted bytecode" 1563 ---help--- 1564 This kernel feature is useful for number crunching applications 1565 that may need to compute untrusted bytecode during their 1566 execution. By using pipes or other transports made available to 1567 the process as file descriptors supporting the read/write 1568 syscalls, it's possible to isolate those applications in 1569 their own address space using seccomp. Once seccomp is 1570 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1571 and the task is only allowed to execute a few safe syscalls 1572 defined by each seccomp mode. 1573 1574 If unsure, say Y. Only embedded should say N here. 1575 1576source kernel/Kconfig.hz 1577 1578config KEXEC 1579 bool "kexec system call" 1580 ---help--- 1581 kexec is a system call that implements the ability to shutdown your 1582 current kernel, and to start another kernel. It is like a reboot 1583 but it is independent of the system firmware. And like a reboot 1584 you can start any kernel with it, not just Linux. 1585 1586 The name comes from the similarity to the exec system call. 1587 1588 It is an ongoing process to be certain the hardware in a machine 1589 is properly shutdown, so do not be surprised if this code does not 1590 initially work for you. As of this writing the exact hardware 1591 interface is strongly in flux, so no good recommendation can be 1592 made. 1593 1594config CRASH_DUMP 1595 bool "kernel crash dumps" 1596 depends on X86_64 || (X86_32 && HIGHMEM) 1597 ---help--- 1598 Generate crash dump after being started by kexec. 1599 This should be normally only set in special crash dump kernels 1600 which are loaded in the main kernel with kexec-tools into 1601 a specially reserved region and then later executed after 1602 a crash by kdump/kexec. The crash dump kernel must be compiled 1603 to a memory address not used by the main kernel or BIOS using 1604 PHYSICAL_START, or it must be built as a relocatable image 1605 (CONFIG_RELOCATABLE=y). 1606 For more details see Documentation/kdump/kdump.txt 1607 1608config KEXEC_JUMP 1609 bool "kexec jump" 1610 depends on KEXEC && HIBERNATION 1611 ---help--- 1612 Jump between original kernel and kexeced kernel and invoke 1613 code in physical address mode via KEXEC 1614 1615config PHYSICAL_START 1616 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1617 default "0x1000000" 1618 ---help--- 1619 This gives the physical address where the kernel is loaded. 1620 1621 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1622 bzImage will decompress itself to above physical address and 1623 run from there. Otherwise, bzImage will run from the address where 1624 it has been loaded by the boot loader and will ignore above physical 1625 address. 1626 1627 In normal kdump cases one does not have to set/change this option 1628 as now bzImage can be compiled as a completely relocatable image 1629 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1630 address. This option is mainly useful for the folks who don't want 1631 to use a bzImage for capturing the crash dump and want to use a 1632 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1633 to be specifically compiled to run from a specific memory area 1634 (normally a reserved region) and this option comes handy. 1635 1636 So if you are using bzImage for capturing the crash dump, 1637 leave the value here unchanged to 0x1000000 and set 1638 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1639 for capturing the crash dump change this value to start of 1640 the reserved region. In other words, it can be set based on 1641 the "X" value as specified in the "crashkernel=YM@XM" 1642 command line boot parameter passed to the panic-ed 1643 kernel. Please take a look at Documentation/kdump/kdump.txt 1644 for more details about crash dumps. 1645 1646 Usage of bzImage for capturing the crash dump is recommended as 1647 one does not have to build two kernels. Same kernel can be used 1648 as production kernel and capture kernel. Above option should have 1649 gone away after relocatable bzImage support is introduced. But it 1650 is present because there are users out there who continue to use 1651 vmlinux for dump capture. This option should go away down the 1652 line. 1653 1654 Don't change this unless you know what you are doing. 1655 1656config RELOCATABLE 1657 bool "Build a relocatable kernel" 1658 default y 1659 ---help--- 1660 This builds a kernel image that retains relocation information 1661 so it can be loaded someplace besides the default 1MB. 1662 The relocations tend to make the kernel binary about 10% larger, 1663 but are discarded at runtime. 1664 1665 One use is for the kexec on panic case where the recovery kernel 1666 must live at a different physical address than the primary 1667 kernel. 1668 1669 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1670 it has been loaded at and the compile time physical address 1671 (CONFIG_PHYSICAL_START) is used as the minimum location. 1672 1673config RANDOMIZE_BASE 1674 bool "Randomize the address of the kernel image" 1675 depends on RELOCATABLE 1676 default n 1677 ---help--- 1678 Randomizes the physical and virtual address at which the 1679 kernel image is decompressed, as a security feature that 1680 deters exploit attempts relying on knowledge of the location 1681 of kernel internals. 1682 1683 Entropy is generated using the RDRAND instruction if it is 1684 supported. If RDTSC is supported, it is used as well. If 1685 neither RDRAND nor RDTSC are supported, then randomness is 1686 read from the i8254 timer. 1687 1688 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1689 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1690 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1691 minimum of 2MiB, only 10 bits of entropy is theoretically 1692 possible. At best, due to page table layouts, 64-bit can use 1693 9 bits of entropy and 32-bit uses 8 bits. 1694 1695 If unsure, say N. 1696 1697config RANDOMIZE_BASE_MAX_OFFSET 1698 hex "Maximum kASLR offset allowed" if EXPERT 1699 depends on RANDOMIZE_BASE 1700 range 0x0 0x20000000 if X86_32 1701 default "0x20000000" if X86_32 1702 range 0x0 0x40000000 if X86_64 1703 default "0x40000000" if X86_64 1704 ---help--- 1705 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1706 memory is used to determine the maximal offset in bytes that will 1707 be applied to the kernel when kernel Address Space Layout 1708 Randomization (kASLR) is active. This must be a multiple of 1709 PHYSICAL_ALIGN. 1710 1711 On 32-bit this is limited to 512MiB by page table layouts. The 1712 default is 512MiB. 1713 1714 On 64-bit this is limited by how the kernel fixmap page table is 1715 positioned, so this cannot be larger than 1GiB currently. Without 1716 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1717 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1718 modules area will shrink to compensate, up to the current maximum 1719 1GiB to 1GiB split. The default is 1GiB. 1720 1721 If unsure, leave at the default value. 1722 1723# Relocation on x86 needs some additional build support 1724config X86_NEED_RELOCS 1725 def_bool y 1726 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1727 1728config PHYSICAL_ALIGN 1729 hex "Alignment value to which kernel should be aligned" 1730 default "0x200000" 1731 range 0x2000 0x1000000 if X86_32 1732 range 0x200000 0x1000000 if X86_64 1733 ---help--- 1734 This value puts the alignment restrictions on physical address 1735 where kernel is loaded and run from. Kernel is compiled for an 1736 address which meets above alignment restriction. 1737 1738 If bootloader loads the kernel at a non-aligned address and 1739 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1740 address aligned to above value and run from there. 1741 1742 If bootloader loads the kernel at a non-aligned address and 1743 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1744 load address and decompress itself to the address it has been 1745 compiled for and run from there. The address for which kernel is 1746 compiled already meets above alignment restrictions. Hence the 1747 end result is that kernel runs from a physical address meeting 1748 above alignment restrictions. 1749 1750 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1751 this value must be a multiple of 0x200000. 1752 1753 Don't change this unless you know what you are doing. 1754 1755config HOTPLUG_CPU 1756 bool "Support for hot-pluggable CPUs" 1757 depends on SMP 1758 ---help--- 1759 Say Y here to allow turning CPUs off and on. CPUs can be 1760 controlled through /sys/devices/system/cpu. 1761 ( Note: power management support will enable this option 1762 automatically on SMP systems. ) 1763 Say N if you want to disable CPU hotplug. 1764 1765config BOOTPARAM_HOTPLUG_CPU0 1766 bool "Set default setting of cpu0_hotpluggable" 1767 default n 1768 depends on HOTPLUG_CPU 1769 ---help--- 1770 Set whether default state of cpu0_hotpluggable is on or off. 1771 1772 Say Y here to enable CPU0 hotplug by default. If this switch 1773 is turned on, there is no need to give cpu0_hotplug kernel 1774 parameter and the CPU0 hotplug feature is enabled by default. 1775 1776 Please note: there are two known CPU0 dependencies if you want 1777 to enable the CPU0 hotplug feature either by this switch or by 1778 cpu0_hotplug kernel parameter. 1779 1780 First, resume from hibernate or suspend always starts from CPU0. 1781 So hibernate and suspend are prevented if CPU0 is offline. 1782 1783 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1784 offline if any interrupt can not migrate out of CPU0. There may 1785 be other CPU0 dependencies. 1786 1787 Please make sure the dependencies are under your control before 1788 you enable this feature. 1789 1790 Say N if you don't want to enable CPU0 hotplug feature by default. 1791 You still can enable the CPU0 hotplug feature at boot by kernel 1792 parameter cpu0_hotplug. 1793 1794config DEBUG_HOTPLUG_CPU0 1795 def_bool n 1796 prompt "Debug CPU0 hotplug" 1797 depends on HOTPLUG_CPU 1798 ---help--- 1799 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 1800 soon as possible and boots up userspace with CPU0 offlined. User 1801 can online CPU0 back after boot time. 1802 1803 To debug CPU0 hotplug, you need to enable CPU0 offline/online 1804 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 1805 compilation or giving cpu0_hotplug kernel parameter at boot. 1806 1807 If unsure, say N. 1808 1809config COMPAT_VDSO 1810 def_bool n 1811 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 1812 depends on X86_32 || IA32_EMULATION 1813 ---help--- 1814 Certain buggy versions of glibc will crash if they are 1815 presented with a 32-bit vDSO that is not mapped at the address 1816 indicated in its segment table. 1817 1818 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 1819 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 1820 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 1821 the only released version with the bug, but OpenSUSE 9 1822 contains a buggy "glibc 2.3.2". 1823 1824 The symptom of the bug is that everything crashes on startup, saying: 1825 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 1826 1827 Saying Y here changes the default value of the vdso32 boot 1828 option from 1 to 0, which turns off the 32-bit vDSO entirely. 1829 This works around the glibc bug but hurts performance. 1830 1831 If unsure, say N: if you are compiling your own kernel, you 1832 are unlikely to be using a buggy version of glibc. 1833 1834config CMDLINE_BOOL 1835 bool "Built-in kernel command line" 1836 ---help--- 1837 Allow for specifying boot arguments to the kernel at 1838 build time. On some systems (e.g. embedded ones), it is 1839 necessary or convenient to provide some or all of the 1840 kernel boot arguments with the kernel itself (that is, 1841 to not rely on the boot loader to provide them.) 1842 1843 To compile command line arguments into the kernel, 1844 set this option to 'Y', then fill in the 1845 the boot arguments in CONFIG_CMDLINE. 1846 1847 Systems with fully functional boot loaders (i.e. non-embedded) 1848 should leave this option set to 'N'. 1849 1850config CMDLINE 1851 string "Built-in kernel command string" 1852 depends on CMDLINE_BOOL 1853 default "" 1854 ---help--- 1855 Enter arguments here that should be compiled into the kernel 1856 image and used at boot time. If the boot loader provides a 1857 command line at boot time, it is appended to this string to 1858 form the full kernel command line, when the system boots. 1859 1860 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1861 change this behavior. 1862 1863 In most cases, the command line (whether built-in or provided 1864 by the boot loader) should specify the device for the root 1865 file system. 1866 1867config CMDLINE_OVERRIDE 1868 bool "Built-in command line overrides boot loader arguments" 1869 depends on CMDLINE_BOOL 1870 ---help--- 1871 Set this option to 'Y' to have the kernel ignore the boot loader 1872 command line, and use ONLY the built-in command line. 1873 1874 This is used to work around broken boot loaders. This should 1875 be set to 'N' under normal conditions. 1876 1877endmenu 1878 1879config ARCH_ENABLE_MEMORY_HOTPLUG 1880 def_bool y 1881 depends on X86_64 || (X86_32 && HIGHMEM) 1882 1883config ARCH_ENABLE_MEMORY_HOTREMOVE 1884 def_bool y 1885 depends on MEMORY_HOTPLUG 1886 1887config USE_PERCPU_NUMA_NODE_ID 1888 def_bool y 1889 depends on NUMA 1890 1891config ARCH_ENABLE_SPLIT_PMD_PTLOCK 1892 def_bool y 1893 depends on X86_64 || X86_PAE 1894 1895config ARCH_ENABLE_HUGEPAGE_MIGRATION 1896 def_bool y 1897 depends on X86_64 && HUGETLB_PAGE && MIGRATION 1898 1899menu "Power management and ACPI options" 1900 1901config ARCH_HIBERNATION_HEADER 1902 def_bool y 1903 depends on X86_64 && HIBERNATION 1904 1905source "kernel/power/Kconfig" 1906 1907source "drivers/acpi/Kconfig" 1908 1909source "drivers/sfi/Kconfig" 1910 1911config X86_APM_BOOT 1912 def_bool y 1913 depends on APM 1914 1915menuconfig APM 1916 tristate "APM (Advanced Power Management) BIOS support" 1917 depends on X86_32 && PM_SLEEP 1918 ---help--- 1919 APM is a BIOS specification for saving power using several different 1920 techniques. This is mostly useful for battery powered laptops with 1921 APM compliant BIOSes. If you say Y here, the system time will be 1922 reset after a RESUME operation, the /proc/apm device will provide 1923 battery status information, and user-space programs will receive 1924 notification of APM "events" (e.g. battery status change). 1925 1926 If you select "Y" here, you can disable actual use of the APM 1927 BIOS by passing the "apm=off" option to the kernel at boot time. 1928 1929 Note that the APM support is almost completely disabled for 1930 machines with more than one CPU. 1931 1932 In order to use APM, you will need supporting software. For location 1933 and more information, read <file:Documentation/power/apm-acpi.txt> 1934 and the Battery Powered Linux mini-HOWTO, available from 1935 <http://www.tldp.org/docs.html#howto>. 1936 1937 This driver does not spin down disk drives (see the hdparm(8) 1938 manpage ("man 8 hdparm") for that), and it doesn't turn off 1939 VESA-compliant "green" monitors. 1940 1941 This driver does not support the TI 4000M TravelMate and the ACER 1942 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1943 desktop machines also don't have compliant BIOSes, and this driver 1944 may cause those machines to panic during the boot phase. 1945 1946 Generally, if you don't have a battery in your machine, there isn't 1947 much point in using this driver and you should say N. If you get 1948 random kernel OOPSes or reboots that don't seem to be related to 1949 anything, try disabling/enabling this option (or disabling/enabling 1950 APM in your BIOS). 1951 1952 Some other things you should try when experiencing seemingly random, 1953 "weird" problems: 1954 1955 1) make sure that you have enough swap space and that it is 1956 enabled. 1957 2) pass the "no-hlt" option to the kernel 1958 3) switch on floating point emulation in the kernel and pass 1959 the "no387" option to the kernel 1960 4) pass the "floppy=nodma" option to the kernel 1961 5) pass the "mem=4M" option to the kernel (thereby disabling 1962 all but the first 4 MB of RAM) 1963 6) make sure that the CPU is not over clocked. 1964 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1965 8) disable the cache from your BIOS settings 1966 9) install a fan for the video card or exchange video RAM 1967 10) install a better fan for the CPU 1968 11) exchange RAM chips 1969 12) exchange the motherboard. 1970 1971 To compile this driver as a module, choose M here: the 1972 module will be called apm. 1973 1974if APM 1975 1976config APM_IGNORE_USER_SUSPEND 1977 bool "Ignore USER SUSPEND" 1978 ---help--- 1979 This option will ignore USER SUSPEND requests. On machines with a 1980 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1981 series notebooks, it is necessary to say Y because of a BIOS bug. 1982 1983config APM_DO_ENABLE 1984 bool "Enable PM at boot time" 1985 ---help--- 1986 Enable APM features at boot time. From page 36 of the APM BIOS 1987 specification: "When disabled, the APM BIOS does not automatically 1988 power manage devices, enter the Standby State, enter the Suspend 1989 State, or take power saving steps in response to CPU Idle calls." 1990 This driver will make CPU Idle calls when Linux is idle (unless this 1991 feature is turned off -- see "Do CPU IDLE calls", below). This 1992 should always save battery power, but more complicated APM features 1993 will be dependent on your BIOS implementation. You may need to turn 1994 this option off if your computer hangs at boot time when using APM 1995 support, or if it beeps continuously instead of suspending. Turn 1996 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1997 T400CDT. This is off by default since most machines do fine without 1998 this feature. 1999 2000config APM_CPU_IDLE 2001 depends on CPU_IDLE 2002 bool "Make CPU Idle calls when idle" 2003 ---help--- 2004 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2005 On some machines, this can activate improved power savings, such as 2006 a slowed CPU clock rate, when the machine is idle. These idle calls 2007 are made after the idle loop has run for some length of time (e.g., 2008 333 mS). On some machines, this will cause a hang at boot time or 2009 whenever the CPU becomes idle. (On machines with more than one CPU, 2010 this option does nothing.) 2011 2012config APM_DISPLAY_BLANK 2013 bool "Enable console blanking using APM" 2014 ---help--- 2015 Enable console blanking using the APM. Some laptops can use this to 2016 turn off the LCD backlight when the screen blanker of the Linux 2017 virtual console blanks the screen. Note that this is only used by 2018 the virtual console screen blanker, and won't turn off the backlight 2019 when using the X Window system. This also doesn't have anything to 2020 do with your VESA-compliant power-saving monitor. Further, this 2021 option doesn't work for all laptops -- it might not turn off your 2022 backlight at all, or it might print a lot of errors to the console, 2023 especially if you are using gpm. 2024 2025config APM_ALLOW_INTS 2026 bool "Allow interrupts during APM BIOS calls" 2027 ---help--- 2028 Normally we disable external interrupts while we are making calls to 2029 the APM BIOS as a measure to lessen the effects of a badly behaving 2030 BIOS implementation. The BIOS should reenable interrupts if it 2031 needs to. Unfortunately, some BIOSes do not -- especially those in 2032 many of the newer IBM Thinkpads. If you experience hangs when you 2033 suspend, try setting this to Y. Otherwise, say N. 2034 2035endif # APM 2036 2037source "drivers/cpufreq/Kconfig" 2038 2039source "drivers/cpuidle/Kconfig" 2040 2041source "drivers/idle/Kconfig" 2042 2043endmenu 2044 2045 2046menu "Bus options (PCI etc.)" 2047 2048config PCI 2049 bool "PCI support" 2050 default y 2051 ---help--- 2052 Find out whether you have a PCI motherboard. PCI is the name of a 2053 bus system, i.e. the way the CPU talks to the other stuff inside 2054 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2055 VESA. If you have PCI, say Y, otherwise N. 2056 2057choice 2058 prompt "PCI access mode" 2059 depends on X86_32 && PCI 2060 default PCI_GOANY 2061 ---help--- 2062 On PCI systems, the BIOS can be used to detect the PCI devices and 2063 determine their configuration. However, some old PCI motherboards 2064 have BIOS bugs and may crash if this is done. Also, some embedded 2065 PCI-based systems don't have any BIOS at all. Linux can also try to 2066 detect the PCI hardware directly without using the BIOS. 2067 2068 With this option, you can specify how Linux should detect the 2069 PCI devices. If you choose "BIOS", the BIOS will be used, 2070 if you choose "Direct", the BIOS won't be used, and if you 2071 choose "MMConfig", then PCI Express MMCONFIG will be used. 2072 If you choose "Any", the kernel will try MMCONFIG, then the 2073 direct access method and falls back to the BIOS if that doesn't 2074 work. If unsure, go with the default, which is "Any". 2075 2076config PCI_GOBIOS 2077 bool "BIOS" 2078 2079config PCI_GOMMCONFIG 2080 bool "MMConfig" 2081 2082config PCI_GODIRECT 2083 bool "Direct" 2084 2085config PCI_GOOLPC 2086 bool "OLPC XO-1" 2087 depends on OLPC 2088 2089config PCI_GOANY 2090 bool "Any" 2091 2092endchoice 2093 2094config PCI_BIOS 2095 def_bool y 2096 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2097 2098# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2099config PCI_DIRECT 2100 def_bool y 2101 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2102 2103config PCI_MMCONFIG 2104 def_bool y 2105 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2106 2107config PCI_OLPC 2108 def_bool y 2109 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2110 2111config PCI_XEN 2112 def_bool y 2113 depends on PCI && XEN 2114 select SWIOTLB_XEN 2115 2116config PCI_DOMAINS 2117 def_bool y 2118 depends on PCI 2119 2120config PCI_MMCONFIG 2121 bool "Support mmconfig PCI config space access" 2122 depends on X86_64 && PCI && ACPI 2123 2124config PCI_CNB20LE_QUIRK 2125 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2126 depends on PCI 2127 help 2128 Read the PCI windows out of the CNB20LE host bridge. This allows 2129 PCI hotplug to work on systems with the CNB20LE chipset which do 2130 not have ACPI. 2131 2132 There's no public spec for this chipset, and this functionality 2133 is known to be incomplete. 2134 2135 You should say N unless you know you need this. 2136 2137source "drivers/pci/pcie/Kconfig" 2138 2139source "drivers/pci/Kconfig" 2140 2141# x86_64 have no ISA slots, but can have ISA-style DMA. 2142config ISA_DMA_API 2143 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2144 default y 2145 help 2146 Enables ISA-style DMA support for devices requiring such controllers. 2147 If unsure, say Y. 2148 2149if X86_32 2150 2151config ISA 2152 bool "ISA support" 2153 ---help--- 2154 Find out whether you have ISA slots on your motherboard. ISA is the 2155 name of a bus system, i.e. the way the CPU talks to the other stuff 2156 inside your box. Other bus systems are PCI, EISA, MicroChannel 2157 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2158 newer boards don't support it. If you have ISA, say Y, otherwise N. 2159 2160config EISA 2161 bool "EISA support" 2162 depends on ISA 2163 ---help--- 2164 The Extended Industry Standard Architecture (EISA) bus was 2165 developed as an open alternative to the IBM MicroChannel bus. 2166 2167 The EISA bus provided some of the features of the IBM MicroChannel 2168 bus while maintaining backward compatibility with cards made for 2169 the older ISA bus. The EISA bus saw limited use between 1988 and 2170 1995 when it was made obsolete by the PCI bus. 2171 2172 Say Y here if you are building a kernel for an EISA-based machine. 2173 2174 Otherwise, say N. 2175 2176source "drivers/eisa/Kconfig" 2177 2178config SCx200 2179 tristate "NatSemi SCx200 support" 2180 ---help--- 2181 This provides basic support for National Semiconductor's 2182 (now AMD's) Geode processors. The driver probes for the 2183 PCI-IDs of several on-chip devices, so its a good dependency 2184 for other scx200_* drivers. 2185 2186 If compiled as a module, the driver is named scx200. 2187 2188config SCx200HR_TIMER 2189 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2190 depends on SCx200 2191 default y 2192 ---help--- 2193 This driver provides a clocksource built upon the on-chip 2194 27MHz high-resolution timer. Its also a workaround for 2195 NSC Geode SC-1100's buggy TSC, which loses time when the 2196 processor goes idle (as is done by the scheduler). The 2197 other workaround is idle=poll boot option. 2198 2199config OLPC 2200 bool "One Laptop Per Child support" 2201 depends on !X86_PAE 2202 select GPIOLIB 2203 select OF 2204 select OF_PROMTREE 2205 select IRQ_DOMAIN 2206 ---help--- 2207 Add support for detecting the unique features of the OLPC 2208 XO hardware. 2209 2210config OLPC_XO1_PM 2211 bool "OLPC XO-1 Power Management" 2212 depends on OLPC && MFD_CS5535 && PM_SLEEP 2213 select MFD_CORE 2214 ---help--- 2215 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2216 2217config OLPC_XO1_RTC 2218 bool "OLPC XO-1 Real Time Clock" 2219 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2220 ---help--- 2221 Add support for the XO-1 real time clock, which can be used as a 2222 programmable wakeup source. 2223 2224config OLPC_XO1_SCI 2225 bool "OLPC XO-1 SCI extras" 2226 depends on OLPC && OLPC_XO1_PM 2227 depends on INPUT=y 2228 select POWER_SUPPLY 2229 select GPIO_CS5535 2230 select MFD_CORE 2231 ---help--- 2232 Add support for SCI-based features of the OLPC XO-1 laptop: 2233 - EC-driven system wakeups 2234 - Power button 2235 - Ebook switch 2236 - Lid switch 2237 - AC adapter status updates 2238 - Battery status updates 2239 2240config OLPC_XO15_SCI 2241 bool "OLPC XO-1.5 SCI extras" 2242 depends on OLPC && ACPI 2243 select POWER_SUPPLY 2244 ---help--- 2245 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2246 - EC-driven system wakeups 2247 - AC adapter status updates 2248 - Battery status updates 2249 2250config ALIX 2251 bool "PCEngines ALIX System Support (LED setup)" 2252 select GPIOLIB 2253 ---help--- 2254 This option enables system support for the PCEngines ALIX. 2255 At present this just sets up LEDs for GPIO control on 2256 ALIX2/3/6 boards. However, other system specific setup should 2257 get added here. 2258 2259 Note: You must still enable the drivers for GPIO and LED support 2260 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2261 2262 Note: You have to set alix.force=1 for boards with Award BIOS. 2263 2264config NET5501 2265 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2266 select GPIOLIB 2267 ---help--- 2268 This option enables system support for the Soekris Engineering net5501. 2269 2270config GEOS 2271 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2272 select GPIOLIB 2273 depends on DMI 2274 ---help--- 2275 This option enables system support for the Traverse Technologies GEOS. 2276 2277config TS5500 2278 bool "Technologic Systems TS-5500 platform support" 2279 depends on MELAN 2280 select CHECK_SIGNATURE 2281 select NEW_LEDS 2282 select LEDS_CLASS 2283 ---help--- 2284 This option enables system support for the Technologic Systems TS-5500. 2285 2286endif # X86_32 2287 2288config AMD_NB 2289 def_bool y 2290 depends on CPU_SUP_AMD && PCI 2291 2292source "drivers/pcmcia/Kconfig" 2293 2294source "drivers/pci/hotplug/Kconfig" 2295 2296config RAPIDIO 2297 tristate "RapidIO support" 2298 depends on PCI 2299 default n 2300 help 2301 If enabled this option will include drivers and the core 2302 infrastructure code to support RapidIO interconnect devices. 2303 2304source "drivers/rapidio/Kconfig" 2305 2306config X86_SYSFB 2307 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2308 help 2309 Firmwares often provide initial graphics framebuffers so the BIOS, 2310 bootloader or kernel can show basic video-output during boot for 2311 user-guidance and debugging. Historically, x86 used the VESA BIOS 2312 Extensions and EFI-framebuffers for this, which are mostly limited 2313 to x86. 2314 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2315 framebuffers so the new generic system-framebuffer drivers can be 2316 used on x86. If the framebuffer is not compatible with the generic 2317 modes, it is adverticed as fallback platform framebuffer so legacy 2318 drivers like efifb, vesafb and uvesafb can pick it up. 2319 If this option is not selected, all system framebuffers are always 2320 marked as fallback platform framebuffers as usual. 2321 2322 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2323 not be able to pick up generic system framebuffers if this option 2324 is selected. You are highly encouraged to enable simplefb as 2325 replacement if you select this option. simplefb can correctly deal 2326 with generic system framebuffers. But you should still keep vesafb 2327 and others enabled as fallback if a system framebuffer is 2328 incompatible with simplefb. 2329 2330 If unsure, say Y. 2331 2332endmenu 2333 2334 2335menu "Executable file formats / Emulations" 2336 2337source "fs/Kconfig.binfmt" 2338 2339config IA32_EMULATION 2340 bool "IA32 Emulation" 2341 depends on X86_64 2342 select BINFMT_ELF 2343 select COMPAT_BINFMT_ELF 2344 select HAVE_UID16 2345 ---help--- 2346 Include code to run legacy 32-bit programs under a 2347 64-bit kernel. You should likely turn this on, unless you're 2348 100% sure that you don't have any 32-bit programs left. 2349 2350config IA32_AOUT 2351 tristate "IA32 a.out support" 2352 depends on IA32_EMULATION 2353 ---help--- 2354 Support old a.out binaries in the 32bit emulation. 2355 2356config X86_X32 2357 bool "x32 ABI for 64-bit mode" 2358 depends on X86_64 && IA32_EMULATION 2359 ---help--- 2360 Include code to run binaries for the x32 native 32-bit ABI 2361 for 64-bit processors. An x32 process gets access to the 2362 full 64-bit register file and wide data path while leaving 2363 pointers at 32 bits for smaller memory footprint. 2364 2365 You will need a recent binutils (2.22 or later) with 2366 elf32_x86_64 support enabled to compile a kernel with this 2367 option set. 2368 2369config COMPAT 2370 def_bool y 2371 depends on IA32_EMULATION || X86_X32 2372 select ARCH_WANT_OLD_COMPAT_IPC 2373 2374if COMPAT 2375config COMPAT_FOR_U64_ALIGNMENT 2376 def_bool y 2377 2378config SYSVIPC_COMPAT 2379 def_bool y 2380 depends on SYSVIPC 2381 2382config KEYS_COMPAT 2383 def_bool y 2384 depends on KEYS 2385endif 2386 2387endmenu 2388 2389 2390config HAVE_ATOMIC_IOMAP 2391 def_bool y 2392 depends on X86_32 2393 2394config X86_DEV_DMA_OPS 2395 bool 2396 depends on X86_64 || STA2X11 2397 2398config X86_DMA_REMAP 2399 bool 2400 depends on STA2X11 2401 2402config IOSF_MBI 2403 tristate 2404 default m 2405 depends on PCI 2406 2407source "net/Kconfig" 2408 2409source "drivers/Kconfig" 2410 2411source "drivers/firmware/Kconfig" 2412 2413source "fs/Kconfig" 2414 2415source "arch/x86/Kconfig.debug" 2416 2417source "security/Kconfig" 2418 2419source "crypto/Kconfig" 2420 2421source "arch/x86/kvm/Kconfig" 2422 2423source "lib/Kconfig" 2424