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 HAVE_AOUT if X86_32 26 select HAVE_UNSTABLE_SCHED_CLOCK 27 select ARCH_SUPPORTS_NUMA_BALANCING 28 select ARCH_WANTS_PROT_NUMA_PROT_NONE 29 select HAVE_IDE 30 select HAVE_OPROFILE 31 select HAVE_PCSPKR_PLATFORM 32 select HAVE_PERF_EVENTS 33 select HAVE_IOREMAP_PROT 34 select HAVE_KPROBES 35 select HAVE_MEMBLOCK 36 select HAVE_MEMBLOCK_NODE_MAP 37 select ARCH_DISCARD_MEMBLOCK 38 select ARCH_WANT_OPTIONAL_GPIOLIB 39 select ARCH_WANT_FRAME_POINTERS 40 select HAVE_DMA_ATTRS 41 select HAVE_DMA_CONTIGUOUS if !SWIOTLB 42 select HAVE_KRETPROBES 43 select HAVE_OPTPROBES 44 select HAVE_KPROBES_ON_FTRACE 45 select HAVE_FTRACE_MCOUNT_RECORD 46 select HAVE_FENTRY if X86_64 47 select HAVE_C_RECORDMCOUNT 48 select HAVE_DYNAMIC_FTRACE 49 select HAVE_DYNAMIC_FTRACE_WITH_REGS 50 select HAVE_FUNCTION_TRACER 51 select HAVE_FUNCTION_GRAPH_TRACER 52 select HAVE_FUNCTION_GRAPH_FP_TEST 53 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 54 select HAVE_SYSCALL_TRACEPOINTS 55 select SYSCTL_EXCEPTION_TRACE 56 select HAVE_KVM 57 select HAVE_ARCH_KGDB 58 select HAVE_ARCH_TRACEHOOK 59 select HAVE_GENERIC_DMA_COHERENT if X86_32 60 select HAVE_EFFICIENT_UNALIGNED_ACCESS 61 select USER_STACKTRACE_SUPPORT 62 select HAVE_REGS_AND_STACK_ACCESS_API 63 select HAVE_DMA_API_DEBUG 64 select HAVE_KERNEL_GZIP 65 select HAVE_KERNEL_BZIP2 66 select HAVE_KERNEL_LZMA 67 select HAVE_KERNEL_XZ 68 select HAVE_KERNEL_LZO 69 select HAVE_KERNEL_LZ4 70 select HAVE_HW_BREAKPOINT 71 select HAVE_MIXED_BREAKPOINTS_REGS 72 select PERF_EVENTS 73 select HAVE_PERF_EVENTS_NMI 74 select HAVE_PERF_REGS 75 select HAVE_PERF_USER_STACK_DUMP 76 select HAVE_DEBUG_KMEMLEAK 77 select ANON_INODES 78 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 79 select HAVE_CMPXCHG_LOCAL 80 select HAVE_CMPXCHG_DOUBLE 81 select HAVE_ARCH_KMEMCHECK 82 select HAVE_USER_RETURN_NOTIFIER 83 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 84 select HAVE_ARCH_JUMP_LABEL 85 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 86 select SPARSE_IRQ 87 select GENERIC_FIND_FIRST_BIT 88 select GENERIC_IRQ_PROBE 89 select GENERIC_PENDING_IRQ if SMP 90 select GENERIC_IRQ_SHOW 91 select GENERIC_CLOCKEVENTS_MIN_ADJUST 92 select IRQ_FORCED_THREADING 93 select USE_GENERIC_SMP_HELPERS if SMP 94 select HAVE_BPF_JIT if X86_64 95 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 96 select CLKEVT_I8253 97 select ARCH_HAVE_NMI_SAFE_CMPXCHG 98 select GENERIC_IOMAP 99 select DCACHE_WORD_ACCESS 100 select GENERIC_SMP_IDLE_THREAD 101 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 102 select HAVE_ARCH_SECCOMP_FILTER 103 select BUILDTIME_EXTABLE_SORT 104 select GENERIC_CMOS_UPDATE 105 select HAVE_ARCH_SOFT_DIRTY 106 select CLOCKSOURCE_WATCHDOG 107 select GENERIC_CLOCKEVENTS 108 select ARCH_CLOCKSOURCE_DATA if X86_64 109 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 110 select GENERIC_TIME_VSYSCALL if X86_64 111 select KTIME_SCALAR if X86_32 112 select GENERIC_STRNCPY_FROM_USER 113 select GENERIC_STRNLEN_USER 114 select HAVE_CONTEXT_TRACKING if X86_64 115 select HAVE_IRQ_TIME_ACCOUNTING 116 select VIRT_TO_BUS 117 select MODULES_USE_ELF_REL if X86_32 118 select MODULES_USE_ELF_RELA if X86_64 119 select CLONE_BACKWARDS if X86_32 120 select ARCH_USE_BUILTIN_BSWAP 121 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 122 select OLD_SIGACTION if X86_32 123 select COMPAT_OLD_SIGACTION if IA32_EMULATION 124 select RTC_LIB 125 select HAVE_DEBUG_STACKOVERFLOW 126 127config INSTRUCTION_DECODER 128 def_bool y 129 depends on KPROBES || PERF_EVENTS || UPROBES 130 131config OUTPUT_FORMAT 132 string 133 default "elf32-i386" if X86_32 134 default "elf64-x86-64" if X86_64 135 136config ARCH_DEFCONFIG 137 string 138 default "arch/x86/configs/i386_defconfig" if X86_32 139 default "arch/x86/configs/x86_64_defconfig" if X86_64 140 141config LOCKDEP_SUPPORT 142 def_bool y 143 144config STACKTRACE_SUPPORT 145 def_bool y 146 147config HAVE_LATENCYTOP_SUPPORT 148 def_bool y 149 150config MMU 151 def_bool y 152 153config SBUS 154 bool 155 156config NEED_DMA_MAP_STATE 157 def_bool y 158 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG 159 160config NEED_SG_DMA_LENGTH 161 def_bool y 162 163config GENERIC_ISA_DMA 164 def_bool y 165 depends on ISA_DMA_API 166 167config GENERIC_BUG 168 def_bool y 169 depends on BUG 170 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 171 172config GENERIC_BUG_RELATIVE_POINTERS 173 bool 174 175config GENERIC_HWEIGHT 176 def_bool y 177 178config ARCH_MAY_HAVE_PC_FDC 179 def_bool y 180 depends on ISA_DMA_API 181 182config RWSEM_XCHGADD_ALGORITHM 183 def_bool y 184 185config GENERIC_CALIBRATE_DELAY 186 def_bool y 187 188config ARCH_HAS_CPU_RELAX 189 def_bool y 190 191config ARCH_HAS_CACHE_LINE_SIZE 192 def_bool y 193 194config ARCH_HAS_CPU_AUTOPROBE 195 def_bool y 196 197config HAVE_SETUP_PER_CPU_AREA 198 def_bool y 199 200config NEED_PER_CPU_EMBED_FIRST_CHUNK 201 def_bool y 202 203config NEED_PER_CPU_PAGE_FIRST_CHUNK 204 def_bool y 205 206config ARCH_HIBERNATION_POSSIBLE 207 def_bool y 208 209config ARCH_SUSPEND_POSSIBLE 210 def_bool y 211 212config ARCH_WANT_HUGE_PMD_SHARE 213 def_bool y 214 215config ARCH_WANT_GENERAL_HUGETLB 216 def_bool y 217 218config ZONE_DMA32 219 bool 220 default X86_64 221 222config AUDIT_ARCH 223 bool 224 default X86_64 225 226config ARCH_SUPPORTS_OPTIMIZED_INLINING 227 def_bool y 228 229config ARCH_SUPPORTS_DEBUG_PAGEALLOC 230 def_bool y 231 232config HAVE_INTEL_TXT 233 def_bool y 234 depends on INTEL_IOMMU && ACPI 235 236config X86_32_SMP 237 def_bool y 238 depends on X86_32 && SMP 239 240config X86_64_SMP 241 def_bool y 242 depends on X86_64 && SMP 243 244config X86_HT 245 def_bool y 246 depends on SMP 247 248config X86_32_LAZY_GS 249 def_bool y 250 depends on X86_32 && !CC_STACKPROTECTOR 251 252config ARCH_HWEIGHT_CFLAGS 253 string 254 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 255 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_64 256 257config ARCH_CPU_PROBE_RELEASE 258 def_bool y 259 depends on HOTPLUG_CPU 260 261config ARCH_SUPPORTS_UPROBES 262 def_bool y 263 264source "init/Kconfig" 265source "kernel/Kconfig.freezer" 266 267menu "Processor type and features" 268 269config ZONE_DMA 270 bool "DMA memory allocation support" if EXPERT 271 default y 272 help 273 DMA memory allocation support allows devices with less than 32-bit 274 addressing to allocate within the first 16MB of address space. 275 Disable if no such devices will be used. 276 277 If unsure, say Y. 278 279config SMP 280 bool "Symmetric multi-processing support" 281 ---help--- 282 This enables support for systems with more than one CPU. If you have 283 a system with only one CPU, like most personal computers, say N. If 284 you have a system with more than one CPU, say Y. 285 286 If you say N here, the kernel will run on single and multiprocessor 287 machines, but will use only one CPU of a multiprocessor machine. If 288 you say Y here, the kernel will run on many, but not all, 289 singleprocessor machines. On a singleprocessor machine, the kernel 290 will run faster if you say N here. 291 292 Note that if you say Y here and choose architecture "586" or 293 "Pentium" under "Processor family", the kernel will not work on 486 294 architectures. Similarly, multiprocessor kernels for the "PPro" 295 architecture may not work on all Pentium based boards. 296 297 People using multiprocessor machines who say Y here should also say 298 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 299 Management" code will be disabled if you say Y here. 300 301 See also <file:Documentation/x86/i386/IO-APIC.txt>, 302 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 303 <http://www.tldp.org/docs.html#howto>. 304 305 If you don't know what to do here, say N. 306 307config X86_X2APIC 308 bool "Support x2apic" 309 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 310 ---help--- 311 This enables x2apic support on CPUs that have this feature. 312 313 This allows 32-bit apic IDs (so it can support very large systems), 314 and accesses the local apic via MSRs not via mmio. 315 316 If you don't know what to do here, say N. 317 318config X86_MPPARSE 319 bool "Enable MPS table" if ACPI || SFI 320 default y 321 depends on X86_LOCAL_APIC 322 ---help--- 323 For old smp systems that do not have proper acpi support. Newer systems 324 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 325 326config X86_BIGSMP 327 bool "Support for big SMP systems with more than 8 CPUs" 328 depends on X86_32 && SMP 329 ---help--- 330 This option is needed for the systems that have more than 8 CPUs 331 332config GOLDFISH 333 def_bool y 334 depends on X86_GOLDFISH 335 336if X86_32 337config X86_EXTENDED_PLATFORM 338 bool "Support for extended (non-PC) x86 platforms" 339 default y 340 ---help--- 341 If you disable this option then the kernel will only support 342 standard PC platforms. (which covers the vast majority of 343 systems out there.) 344 345 If you enable this option then you'll be able to select support 346 for the following (non-PC) 32 bit x86 platforms: 347 Goldfish (Android emulator) 348 AMD Elan 349 NUMAQ (IBM/Sequent) 350 RDC R-321x SoC 351 SGI 320/540 (Visual Workstation) 352 STA2X11-based (e.g. Northville) 353 Summit/EXA (IBM x440) 354 Unisys ES7000 IA32 series 355 Moorestown MID devices 356 357 If you have one of these systems, or if you want to build a 358 generic distribution kernel, say Y here - otherwise say N. 359endif 360 361if X86_64 362config X86_EXTENDED_PLATFORM 363 bool "Support for extended (non-PC) x86 platforms" 364 default y 365 ---help--- 366 If you disable this option then the kernel will only support 367 standard PC platforms. (which covers the vast majority of 368 systems out there.) 369 370 If you enable this option then you'll be able to select support 371 for the following (non-PC) 64 bit x86 platforms: 372 Numascale NumaChip 373 ScaleMP vSMP 374 SGI Ultraviolet 375 376 If you have one of these systems, or if you want to build a 377 generic distribution kernel, say Y here - otherwise say N. 378endif 379# This is an alphabetically sorted list of 64 bit extended platforms 380# Please maintain the alphabetic order if and when there are additions 381config X86_NUMACHIP 382 bool "Numascale NumaChip" 383 depends on X86_64 384 depends on X86_EXTENDED_PLATFORM 385 depends on NUMA 386 depends on SMP 387 depends on X86_X2APIC 388 depends on PCI_MMCONFIG 389 ---help--- 390 Adds support for Numascale NumaChip large-SMP systems. Needed to 391 enable more than ~168 cores. 392 If you don't have one of these, you should say N here. 393 394config X86_VSMP 395 bool "ScaleMP vSMP" 396 select HYPERVISOR_GUEST 397 select PARAVIRT 398 depends on X86_64 && PCI 399 depends on X86_EXTENDED_PLATFORM 400 depends on SMP 401 ---help--- 402 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 403 supposed to run on these EM64T-based machines. Only choose this option 404 if you have one of these machines. 405 406config X86_UV 407 bool "SGI Ultraviolet" 408 depends on X86_64 409 depends on X86_EXTENDED_PLATFORM 410 depends on NUMA 411 depends on X86_X2APIC 412 ---help--- 413 This option is needed in order to support SGI Ultraviolet systems. 414 If you don't have one of these, you should say N here. 415 416# Following is an alphabetically sorted list of 32 bit extended platforms 417# Please maintain the alphabetic order if and when there are additions 418 419config X86_GOLDFISH 420 bool "Goldfish (Virtual Platform)" 421 depends on X86_32 422 depends on X86_EXTENDED_PLATFORM 423 ---help--- 424 Enable support for the Goldfish virtual platform used primarily 425 for Android development. Unless you are building for the Android 426 Goldfish emulator say N here. 427 428config X86_INTEL_CE 429 bool "CE4100 TV platform" 430 depends on PCI 431 depends on PCI_GODIRECT 432 depends on X86_32 433 depends on X86_EXTENDED_PLATFORM 434 select X86_REBOOTFIXUPS 435 select OF 436 select OF_EARLY_FLATTREE 437 select IRQ_DOMAIN 438 ---help--- 439 Select for the Intel CE media processor (CE4100) SOC. 440 This option compiles in support for the CE4100 SOC for settop 441 boxes and media devices. 442 443config X86_WANT_INTEL_MID 444 bool "Intel MID platform support" 445 depends on X86_32 446 depends on X86_EXTENDED_PLATFORM 447 ---help--- 448 Select to build a kernel capable of supporting Intel MID platform 449 systems which do not have the PCI legacy interfaces (Moorestown, 450 Medfield). If you are building for a PC class system say N here. 451 452if X86_WANT_INTEL_MID 453 454config X86_INTEL_MID 455 bool 456 457config X86_MDFLD 458 bool "Medfield MID platform" 459 depends on PCI 460 depends on PCI_GOANY 461 depends on X86_IO_APIC 462 select X86_INTEL_MID 463 select SFI 464 select DW_APB_TIMER 465 select APB_TIMER 466 select I2C 467 select SPI 468 select INTEL_SCU_IPC 469 select X86_PLATFORM_DEVICES 470 select MFD_INTEL_MSIC 471 ---help--- 472 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin 473 Internet Device(MID) platform. 474 Unlike standard x86 PCs, Medfield does not have many legacy devices 475 nor standard legacy replacement devices/features. e.g. Medfield does 476 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 477 478endif 479 480config X86_INTEL_LPSS 481 bool "Intel Low Power Subsystem Support" 482 depends on ACPI 483 select COMMON_CLK 484 select PINCTRL 485 ---help--- 486 Select to build support for Intel Low Power Subsystem such as 487 found on Intel Lynxpoint PCH. Selecting this option enables 488 things like clock tree (common clock framework) and pincontrol 489 which are needed by the LPSS peripheral drivers. 490 491config X86_RDC321X 492 bool "RDC R-321x SoC" 493 depends on X86_32 494 depends on X86_EXTENDED_PLATFORM 495 select M486 496 select X86_REBOOTFIXUPS 497 ---help--- 498 This option is needed for RDC R-321x system-on-chip, also known 499 as R-8610-(G). 500 If you don't have one of these chips, you should say N here. 501 502config X86_32_NON_STANDARD 503 bool "Support non-standard 32-bit SMP architectures" 504 depends on X86_32 && SMP 505 depends on X86_EXTENDED_PLATFORM 506 ---help--- 507 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, 508 STA2X11, default subarchitectures. It is intended for a generic 509 binary kernel. If you select them all, kernel will probe it 510 one by one and will fallback to default. 511 512# Alphabetically sorted list of Non standard 32 bit platforms 513 514config X86_NUMAQ 515 bool "NUMAQ (IBM/Sequent)" 516 depends on X86_32_NON_STANDARD 517 depends on PCI 518 select NUMA 519 select X86_MPPARSE 520 ---help--- 521 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 522 NUMA multiquad box. This changes the way that processors are 523 bootstrapped, and uses Clustered Logical APIC addressing mode instead 524 of Flat Logical. You will need a new lynxer.elf file to flash your 525 firmware with - send email to <Martin.Bligh@us.ibm.com>. 526 527config X86_SUPPORTS_MEMORY_FAILURE 528 def_bool y 529 # MCE code calls memory_failure(): 530 depends on X86_MCE 531 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 532 depends on !X86_NUMAQ 533 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 534 depends on X86_64 || !SPARSEMEM 535 select ARCH_SUPPORTS_MEMORY_FAILURE 536 537config X86_VISWS 538 bool "SGI 320/540 (Visual Workstation)" 539 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 540 depends on X86_32_NON_STANDARD 541 ---help--- 542 The SGI Visual Workstation series is an IA32-based workstation 543 based on SGI systems chips with some legacy PC hardware attached. 544 545 Say Y here to create a kernel to run on the SGI 320 or 540. 546 547 A kernel compiled for the Visual Workstation will run on general 548 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 549 550config STA2X11 551 bool "STA2X11 Companion Chip Support" 552 depends on X86_32_NON_STANDARD && PCI 553 select X86_DEV_DMA_OPS 554 select X86_DMA_REMAP 555 select SWIOTLB 556 select MFD_STA2X11 557 select ARCH_REQUIRE_GPIOLIB 558 default n 559 ---help--- 560 This adds support for boards based on the STA2X11 IO-Hub, 561 a.k.a. "ConneXt". The chip is used in place of the standard 562 PC chipset, so all "standard" peripherals are missing. If this 563 option is selected the kernel will still be able to boot on 564 standard PC machines. 565 566config X86_SUMMIT 567 bool "Summit/EXA (IBM x440)" 568 depends on X86_32_NON_STANDARD 569 ---help--- 570 This option is needed for IBM systems that use the Summit/EXA chipset. 571 In particular, it is needed for the x440. 572 573config X86_ES7000 574 bool "Unisys ES7000 IA32 series" 575 depends on X86_32_NON_STANDARD && X86_BIGSMP 576 ---help--- 577 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 578 supposed to run on an IA32-based Unisys ES7000 system. 579 580config X86_32_IRIS 581 tristate "Eurobraille/Iris poweroff module" 582 depends on X86_32 583 ---help--- 584 The Iris machines from EuroBraille do not have APM or ACPI support 585 to shut themselves down properly. A special I/O sequence is 586 needed to do so, which is what this module does at 587 kernel shutdown. 588 589 This is only for Iris machines from EuroBraille. 590 591 If unused, say N. 592 593config SCHED_OMIT_FRAME_POINTER 594 def_bool y 595 prompt "Single-depth WCHAN output" 596 depends on X86 597 ---help--- 598 Calculate simpler /proc/<PID>/wchan values. If this option 599 is disabled then wchan values will recurse back to the 600 caller function. This provides more accurate wchan values, 601 at the expense of slightly more scheduling overhead. 602 603 If in doubt, say "Y". 604 605menuconfig HYPERVISOR_GUEST 606 bool "Linux guest support" 607 ---help--- 608 Say Y here to enable options for running Linux under various hyper- 609 visors. This option enables basic hypervisor detection and platform 610 setup. 611 612 If you say N, all options in this submenu will be skipped and 613 disabled, and Linux guest support won't be built in. 614 615if HYPERVISOR_GUEST 616 617config PARAVIRT 618 bool "Enable paravirtualization code" 619 ---help--- 620 This changes the kernel so it can modify itself when it is run 621 under a hypervisor, potentially improving performance significantly 622 over full virtualization. However, when run without a hypervisor 623 the kernel is theoretically slower and slightly larger. 624 625config PARAVIRT_DEBUG 626 bool "paravirt-ops debugging" 627 depends on PARAVIRT && DEBUG_KERNEL 628 ---help--- 629 Enable to debug paravirt_ops internals. Specifically, BUG if 630 a paravirt_op is missing when it is called. 631 632config PARAVIRT_SPINLOCKS 633 bool "Paravirtualization layer for spinlocks" 634 depends on PARAVIRT && SMP 635 select UNINLINE_SPIN_UNLOCK 636 ---help--- 637 Paravirtualized spinlocks allow a pvops backend to replace the 638 spinlock implementation with something virtualization-friendly 639 (for example, block the virtual CPU rather than spinning). 640 641 Unfortunately the downside is an up to 5% performance hit on 642 native kernels, with various workloads. 643 644 If you are unsure how to answer this question, answer N. 645 646source "arch/x86/xen/Kconfig" 647 648config KVM_GUEST 649 bool "KVM Guest support (including kvmclock)" 650 depends on PARAVIRT 651 select PARAVIRT_CLOCK 652 default y 653 ---help--- 654 This option enables various optimizations for running under the KVM 655 hypervisor. It includes a paravirtualized clock, so that instead 656 of relying on a PIT (or probably other) emulation by the 657 underlying device model, the host provides the guest with 658 timing infrastructure such as time of day, and system time 659 660config KVM_DEBUG_FS 661 bool "Enable debug information for KVM Guests in debugfs" 662 depends on KVM_GUEST && DEBUG_FS 663 default n 664 ---help--- 665 This option enables collection of various statistics for KVM guest. 666 Statistics are displayed in debugfs filesystem. Enabling this option 667 may incur significant overhead. 668 669source "arch/x86/lguest/Kconfig" 670 671config PARAVIRT_TIME_ACCOUNTING 672 bool "Paravirtual steal time accounting" 673 depends on PARAVIRT 674 default n 675 ---help--- 676 Select this option to enable fine granularity task steal time 677 accounting. Time spent executing other tasks in parallel with 678 the current vCPU is discounted from the vCPU power. To account for 679 that, there can be a small performance impact. 680 681 If in doubt, say N here. 682 683config PARAVIRT_CLOCK 684 bool 685 686endif #HYPERVISOR_GUEST 687 688config NO_BOOTMEM 689 def_bool y 690 691config MEMTEST 692 bool "Memtest" 693 ---help--- 694 This option adds a kernel parameter 'memtest', which allows memtest 695 to be set. 696 memtest=0, mean disabled; -- default 697 memtest=1, mean do 1 test pattern; 698 ... 699 memtest=4, mean do 4 test patterns. 700 If you are unsure how to answer this question, answer N. 701 702config X86_SUMMIT_NUMA 703 def_bool y 704 depends on X86_32 && NUMA && X86_32_NON_STANDARD 705 706config X86_CYCLONE_TIMER 707 def_bool y 708 depends on X86_SUMMIT 709 710source "arch/x86/Kconfig.cpu" 711 712config HPET_TIMER 713 def_bool X86_64 714 prompt "HPET Timer Support" if X86_32 715 ---help--- 716 Use the IA-PC HPET (High Precision Event Timer) to manage 717 time in preference to the PIT and RTC, if a HPET is 718 present. 719 HPET is the next generation timer replacing legacy 8254s. 720 The HPET provides a stable time base on SMP 721 systems, unlike the TSC, but it is more expensive to access, 722 as it is off-chip. You can find the HPET spec at 723 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 724 725 You can safely choose Y here. However, HPET will only be 726 activated if the platform and the BIOS support this feature. 727 Otherwise the 8254 will be used for timing services. 728 729 Choose N to continue using the legacy 8254 timer. 730 731config HPET_EMULATE_RTC 732 def_bool y 733 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 734 735config APB_TIMER 736 def_bool y if X86_INTEL_MID 737 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 738 select DW_APB_TIMER 739 depends on X86_INTEL_MID && SFI 740 help 741 APB timer is the replacement for 8254, HPET on X86 MID platforms. 742 The APBT provides a stable time base on SMP 743 systems, unlike the TSC, but it is more expensive to access, 744 as it is off-chip. APB timers are always running regardless of CPU 745 C states, they are used as per CPU clockevent device when possible. 746 747# Mark as expert because too many people got it wrong. 748# The code disables itself when not needed. 749config DMI 750 default y 751 bool "Enable DMI scanning" if EXPERT 752 ---help--- 753 Enabled scanning of DMI to identify machine quirks. Say Y 754 here unless you have verified that your setup is not 755 affected by entries in the DMI blacklist. Required by PNP 756 BIOS code. 757 758config GART_IOMMU 759 bool "GART IOMMU support" if EXPERT 760 default y 761 select SWIOTLB 762 depends on X86_64 && PCI && AMD_NB 763 ---help--- 764 Support for full DMA access of devices with 32bit memory access only 765 on systems with more than 3GB. This is usually needed for USB, 766 sound, many IDE/SATA chipsets and some other devices. 767 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 768 based hardware IOMMU and a software bounce buffer based IOMMU used 769 on Intel systems and as fallback. 770 The code is only active when needed (enough memory and limited 771 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 772 too. 773 774config CALGARY_IOMMU 775 bool "IBM Calgary IOMMU support" 776 select SWIOTLB 777 depends on X86_64 && PCI 778 ---help--- 779 Support for hardware IOMMUs in IBM's xSeries x366 and x460 780 systems. Needed to run systems with more than 3GB of memory 781 properly with 32-bit PCI devices that do not support DAC 782 (Double Address Cycle). Calgary also supports bus level 783 isolation, where all DMAs pass through the IOMMU. This 784 prevents them from going anywhere except their intended 785 destination. This catches hard-to-find kernel bugs and 786 mis-behaving drivers and devices that do not use the DMA-API 787 properly to set up their DMA buffers. The IOMMU can be 788 turned off at boot time with the iommu=off parameter. 789 Normally the kernel will make the right choice by itself. 790 If unsure, say Y. 791 792config CALGARY_IOMMU_ENABLED_BY_DEFAULT 793 def_bool y 794 prompt "Should Calgary be enabled by default?" 795 depends on CALGARY_IOMMU 796 ---help--- 797 Should Calgary be enabled by default? if you choose 'y', Calgary 798 will be used (if it exists). If you choose 'n', Calgary will not be 799 used even if it exists. If you choose 'n' and would like to use 800 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 801 If unsure, say Y. 802 803# need this always selected by IOMMU for the VIA workaround 804config SWIOTLB 805 def_bool y if X86_64 806 ---help--- 807 Support for software bounce buffers used on x86-64 systems 808 which don't have a hardware IOMMU. Using this PCI devices 809 which can only access 32-bits of memory can be used on systems 810 with more than 3 GB of memory. 811 If unsure, say Y. 812 813config IOMMU_HELPER 814 def_bool y 815 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 816 817config MAXSMP 818 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 819 depends on X86_64 && SMP && DEBUG_KERNEL 820 select CPUMASK_OFFSTACK 821 ---help--- 822 Enable maximum number of CPUS and NUMA Nodes for this architecture. 823 If unsure, say N. 824 825config NR_CPUS 826 int "Maximum number of CPUs" if SMP && !MAXSMP 827 range 2 8 if SMP && X86_32 && !X86_BIGSMP 828 range 2 512 if SMP && !MAXSMP 829 default "1" if !SMP 830 default "4096" if MAXSMP 831 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 832 default "8" if SMP 833 ---help--- 834 This allows you to specify the maximum number of CPUs which this 835 kernel will support. The maximum supported value is 512 and the 836 minimum value which makes sense is 2. 837 838 This is purely to save memory - each supported CPU adds 839 approximately eight kilobytes to the kernel image. 840 841config SCHED_SMT 842 bool "SMT (Hyperthreading) scheduler support" 843 depends on X86_HT 844 ---help--- 845 SMT scheduler support improves the CPU scheduler's decision making 846 when dealing with Intel Pentium 4 chips with HyperThreading at a 847 cost of slightly increased overhead in some places. If unsure say 848 N here. 849 850config SCHED_MC 851 def_bool y 852 prompt "Multi-core scheduler support" 853 depends on X86_HT 854 ---help--- 855 Multi-core scheduler support improves the CPU scheduler's decision 856 making when dealing with multi-core CPU chips at a cost of slightly 857 increased overhead in some places. If unsure say N here. 858 859source "kernel/Kconfig.preempt" 860 861config X86_UP_APIC 862 bool "Local APIC support on uniprocessors" 863 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI 864 ---help--- 865 A local APIC (Advanced Programmable Interrupt Controller) is an 866 integrated interrupt controller in the CPU. If you have a single-CPU 867 system which has a processor with a local APIC, you can say Y here to 868 enable and use it. If you say Y here even though your machine doesn't 869 have a local APIC, then the kernel will still run with no slowdown at 870 all. The local APIC supports CPU-generated self-interrupts (timer, 871 performance counters), and the NMI watchdog which detects hard 872 lockups. 873 874config X86_UP_IOAPIC 875 bool "IO-APIC support on uniprocessors" 876 depends on X86_UP_APIC 877 ---help--- 878 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 879 SMP-capable replacement for PC-style interrupt controllers. Most 880 SMP systems and many recent uniprocessor systems have one. 881 882 If you have a single-CPU system with an IO-APIC, you can say Y here 883 to use it. If you say Y here even though your machine doesn't have 884 an IO-APIC, then the kernel will still run with no slowdown at all. 885 886config X86_LOCAL_APIC 887 def_bool y 888 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 889 890config X86_IO_APIC 891 def_bool y 892 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI 893 894config X86_VISWS_APIC 895 def_bool y 896 depends on X86_32 && X86_VISWS 897 898config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 899 bool "Reroute for broken boot IRQs" 900 depends on X86_IO_APIC 901 ---help--- 902 This option enables a workaround that fixes a source of 903 spurious interrupts. This is recommended when threaded 904 interrupt handling is used on systems where the generation of 905 superfluous "boot interrupts" cannot be disabled. 906 907 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 908 entry in the chipset's IO-APIC is masked (as, e.g. the RT 909 kernel does during interrupt handling). On chipsets where this 910 boot IRQ generation cannot be disabled, this workaround keeps 911 the original IRQ line masked so that only the equivalent "boot 912 IRQ" is delivered to the CPUs. The workaround also tells the 913 kernel to set up the IRQ handler on the boot IRQ line. In this 914 way only one interrupt is delivered to the kernel. Otherwise 915 the spurious second interrupt may cause the kernel to bring 916 down (vital) interrupt lines. 917 918 Only affects "broken" chipsets. Interrupt sharing may be 919 increased on these systems. 920 921config X86_MCE 922 bool "Machine Check / overheating reporting" 923 default y 924 ---help--- 925 Machine Check support allows the processor to notify the 926 kernel if it detects a problem (e.g. overheating, data corruption). 927 The action the kernel takes depends on the severity of the problem, 928 ranging from warning messages to halting the machine. 929 930config X86_MCE_INTEL 931 def_bool y 932 prompt "Intel MCE features" 933 depends on X86_MCE && X86_LOCAL_APIC 934 ---help--- 935 Additional support for intel specific MCE features such as 936 the thermal monitor. 937 938config X86_MCE_AMD 939 def_bool y 940 prompt "AMD MCE features" 941 depends on X86_MCE && X86_LOCAL_APIC 942 ---help--- 943 Additional support for AMD specific MCE features such as 944 the DRAM Error Threshold. 945 946config X86_ANCIENT_MCE 947 bool "Support for old Pentium 5 / WinChip machine checks" 948 depends on X86_32 && X86_MCE 949 ---help--- 950 Include support for machine check handling on old Pentium 5 or WinChip 951 systems. These typically need to be enabled explicitely on the command 952 line. 953 954config X86_MCE_THRESHOLD 955 depends on X86_MCE_AMD || X86_MCE_INTEL 956 def_bool y 957 958config X86_MCE_INJECT 959 depends on X86_MCE 960 tristate "Machine check injector support" 961 ---help--- 962 Provide support for injecting machine checks for testing purposes. 963 If you don't know what a machine check is and you don't do kernel 964 QA it is safe to say n. 965 966config X86_THERMAL_VECTOR 967 def_bool y 968 depends on X86_MCE_INTEL 969 970config VM86 971 bool "Enable VM86 support" if EXPERT 972 default y 973 depends on X86_32 974 ---help--- 975 This option is required by programs like DOSEMU to run 16-bit legacy 976 code on X86 processors. It also may be needed by software like 977 XFree86 to initialize some video cards via BIOS. Disabling this 978 option saves about 6k. 979 980config TOSHIBA 981 tristate "Toshiba Laptop support" 982 depends on X86_32 983 ---help--- 984 This adds a driver to safely access the System Management Mode of 985 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 986 not work on models with a Phoenix BIOS. The System Management Mode 987 is used to set the BIOS and power saving options on Toshiba portables. 988 989 For information on utilities to make use of this driver see the 990 Toshiba Linux utilities web site at: 991 <http://www.buzzard.org.uk/toshiba/>. 992 993 Say Y if you intend to run this kernel on a Toshiba portable. 994 Say N otherwise. 995 996config I8K 997 tristate "Dell laptop support" 998 select HWMON 999 ---help--- 1000 This adds a driver to safely access the System Management Mode 1001 of the CPU on the Dell Inspiron 8000. The System Management Mode 1002 is used to read cpu temperature and cooling fan status and to 1003 control the fans on the I8K portables. 1004 1005 This driver has been tested only on the Inspiron 8000 but it may 1006 also work with other Dell laptops. You can force loading on other 1007 models by passing the parameter `force=1' to the module. Use at 1008 your own risk. 1009 1010 For information on utilities to make use of this driver see the 1011 I8K Linux utilities web site at: 1012 <http://people.debian.org/~dz/i8k/> 1013 1014 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 1015 Say N otherwise. 1016 1017config X86_REBOOTFIXUPS 1018 bool "Enable X86 board specific fixups for reboot" 1019 depends on X86_32 1020 ---help--- 1021 This enables chipset and/or board specific fixups to be done 1022 in order to get reboot to work correctly. This is only needed on 1023 some combinations of hardware and BIOS. The symptom, for which 1024 this config is intended, is when reboot ends with a stalled/hung 1025 system. 1026 1027 Currently, the only fixup is for the Geode machines using 1028 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1029 1030 Say Y if you want to enable the fixup. Currently, it's safe to 1031 enable this option even if you don't need it. 1032 Say N otherwise. 1033 1034config MICROCODE 1035 tristate "CPU microcode loading support" 1036 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1037 select FW_LOADER 1038 ---help--- 1039 1040 If you say Y here, you will be able to update the microcode on 1041 certain Intel and AMD processors. The Intel support is for the 1042 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1043 Xeon etc. The AMD support is for families 0x10 and later. You will 1044 obviously need the actual microcode binary data itself which is not 1045 shipped with the Linux kernel. 1046 1047 This option selects the general module only, you need to select 1048 at least one vendor specific module as well. 1049 1050 To compile this driver as a module, choose M here: the module 1051 will be called microcode. 1052 1053config MICROCODE_INTEL 1054 bool "Intel microcode loading support" 1055 depends on MICROCODE 1056 default MICROCODE 1057 select FW_LOADER 1058 ---help--- 1059 This options enables microcode patch loading support for Intel 1060 processors. 1061 1062 For latest news and information on obtaining all the required 1063 Intel ingredients for this driver, check: 1064 <http://www.urbanmyth.org/microcode/>. 1065 1066config MICROCODE_AMD 1067 bool "AMD microcode loading support" 1068 depends on MICROCODE 1069 select FW_LOADER 1070 ---help--- 1071 If you select this option, microcode patch loading support for AMD 1072 processors will be enabled. 1073 1074config MICROCODE_OLD_INTERFACE 1075 def_bool y 1076 depends on MICROCODE 1077 1078config MICROCODE_INTEL_LIB 1079 def_bool y 1080 depends on MICROCODE_INTEL 1081 1082config MICROCODE_INTEL_EARLY 1083 def_bool n 1084 1085config MICROCODE_AMD_EARLY 1086 def_bool n 1087 1088config MICROCODE_EARLY 1089 bool "Early load microcode" 1090 depends on MICROCODE=y && BLK_DEV_INITRD 1091 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1092 select MICROCODE_AMD_EARLY if MICROCODE_AMD 1093 default y 1094 help 1095 This option provides functionality to read additional microcode data 1096 at the beginning of initrd image. The data tells kernel to load 1097 microcode to CPU's as early as possible. No functional change if no 1098 microcode data is glued to the initrd, therefore it's safe to say Y. 1099 1100config X86_MSR 1101 tristate "/dev/cpu/*/msr - Model-specific register support" 1102 ---help--- 1103 This device gives privileged processes access to the x86 1104 Model-Specific Registers (MSRs). It is a character device with 1105 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1106 MSR accesses are directed to a specific CPU on multi-processor 1107 systems. 1108 1109config X86_CPUID 1110 tristate "/dev/cpu/*/cpuid - CPU information support" 1111 ---help--- 1112 This device gives processes access to the x86 CPUID instruction to 1113 be executed on a specific processor. It is a character device 1114 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1115 /dev/cpu/31/cpuid. 1116 1117choice 1118 prompt "High Memory Support" 1119 default HIGHMEM64G if X86_NUMAQ 1120 default HIGHMEM4G 1121 depends on X86_32 1122 1123config NOHIGHMEM 1124 bool "off" 1125 depends on !X86_NUMAQ 1126 ---help--- 1127 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1128 However, the address space of 32-bit x86 processors is only 4 1129 Gigabytes large. That means that, if you have a large amount of 1130 physical memory, not all of it can be "permanently mapped" by the 1131 kernel. The physical memory that's not permanently mapped is called 1132 "high memory". 1133 1134 If you are compiling a kernel which will never run on a machine with 1135 more than 1 Gigabyte total physical RAM, answer "off" here (default 1136 choice and suitable for most users). This will result in a "3GB/1GB" 1137 split: 3GB are mapped so that each process sees a 3GB virtual memory 1138 space and the remaining part of the 4GB virtual memory space is used 1139 by the kernel to permanently map as much physical memory as 1140 possible. 1141 1142 If the machine has between 1 and 4 Gigabytes physical RAM, then 1143 answer "4GB" here. 1144 1145 If more than 4 Gigabytes is used then answer "64GB" here. This 1146 selection turns Intel PAE (Physical Address Extension) mode on. 1147 PAE implements 3-level paging on IA32 processors. PAE is fully 1148 supported by Linux, PAE mode is implemented on all recent Intel 1149 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1150 then the kernel will not boot on CPUs that don't support PAE! 1151 1152 The actual amount of total physical memory will either be 1153 auto detected or can be forced by using a kernel command line option 1154 such as "mem=256M". (Try "man bootparam" or see the documentation of 1155 your boot loader (lilo or loadlin) about how to pass options to the 1156 kernel at boot time.) 1157 1158 If unsure, say "off". 1159 1160config HIGHMEM4G 1161 bool "4GB" 1162 depends on !X86_NUMAQ 1163 ---help--- 1164 Select this if you have a 32-bit processor and between 1 and 4 1165 gigabytes of physical RAM. 1166 1167config HIGHMEM64G 1168 bool "64GB" 1169 depends on !M486 1170 select X86_PAE 1171 ---help--- 1172 Select this if you have a 32-bit processor and more than 4 1173 gigabytes of physical RAM. 1174 1175endchoice 1176 1177choice 1178 prompt "Memory split" if EXPERT 1179 default VMSPLIT_3G 1180 depends on X86_32 1181 ---help--- 1182 Select the desired split between kernel and user memory. 1183 1184 If the address range available to the kernel is less than the 1185 physical memory installed, the remaining memory will be available 1186 as "high memory". Accessing high memory is a little more costly 1187 than low memory, as it needs to be mapped into the kernel first. 1188 Note that increasing the kernel address space limits the range 1189 available to user programs, making the address space there 1190 tighter. Selecting anything other than the default 3G/1G split 1191 will also likely make your kernel incompatible with binary-only 1192 kernel modules. 1193 1194 If you are not absolutely sure what you are doing, leave this 1195 option alone! 1196 1197 config VMSPLIT_3G 1198 bool "3G/1G user/kernel split" 1199 config VMSPLIT_3G_OPT 1200 depends on !X86_PAE 1201 bool "3G/1G user/kernel split (for full 1G low memory)" 1202 config VMSPLIT_2G 1203 bool "2G/2G user/kernel split" 1204 config VMSPLIT_2G_OPT 1205 depends on !X86_PAE 1206 bool "2G/2G user/kernel split (for full 2G low memory)" 1207 config VMSPLIT_1G 1208 bool "1G/3G user/kernel split" 1209endchoice 1210 1211config PAGE_OFFSET 1212 hex 1213 default 0xB0000000 if VMSPLIT_3G_OPT 1214 default 0x80000000 if VMSPLIT_2G 1215 default 0x78000000 if VMSPLIT_2G_OPT 1216 default 0x40000000 if VMSPLIT_1G 1217 default 0xC0000000 1218 depends on X86_32 1219 1220config HIGHMEM 1221 def_bool y 1222 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1223 1224config X86_PAE 1225 bool "PAE (Physical Address Extension) Support" 1226 depends on X86_32 && !HIGHMEM4G 1227 ---help--- 1228 PAE is required for NX support, and furthermore enables 1229 larger swapspace support for non-overcommit purposes. It 1230 has the cost of more pagetable lookup overhead, and also 1231 consumes more pagetable space per process. 1232 1233config ARCH_PHYS_ADDR_T_64BIT 1234 def_bool y 1235 depends on X86_64 || X86_PAE 1236 1237config ARCH_DMA_ADDR_T_64BIT 1238 def_bool y 1239 depends on X86_64 || HIGHMEM64G 1240 1241config DIRECT_GBPAGES 1242 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1243 default y 1244 depends on X86_64 1245 ---help--- 1246 Allow the kernel linear mapping to use 1GB pages on CPUs that 1247 support it. This can improve the kernel's performance a tiny bit by 1248 reducing TLB pressure. If in doubt, say "Y". 1249 1250# Common NUMA Features 1251config NUMA 1252 bool "Numa Memory Allocation and Scheduler Support" 1253 depends on SMP 1254 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI)) 1255 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1256 ---help--- 1257 Enable NUMA (Non Uniform Memory Access) support. 1258 1259 The kernel will try to allocate memory used by a CPU on the 1260 local memory controller of the CPU and add some more 1261 NUMA awareness to the kernel. 1262 1263 For 64-bit this is recommended if the system is Intel Core i7 1264 (or later), AMD Opteron, or EM64T NUMA. 1265 1266 For 32-bit this is only needed on (rare) 32-bit-only platforms 1267 that support NUMA topologies, such as NUMAQ / Summit, or if you 1268 boot a 32-bit kernel on a 64-bit NUMA platform. 1269 1270 Otherwise, you should say N. 1271 1272comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1273 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1274 1275config AMD_NUMA 1276 def_bool y 1277 prompt "Old style AMD Opteron NUMA detection" 1278 depends on X86_64 && NUMA && PCI 1279 ---help--- 1280 Enable AMD NUMA node topology detection. You should say Y here if 1281 you have a multi processor AMD system. This uses an old method to 1282 read the NUMA configuration directly from the builtin Northbridge 1283 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1284 which also takes priority if both are compiled in. 1285 1286config X86_64_ACPI_NUMA 1287 def_bool y 1288 prompt "ACPI NUMA detection" 1289 depends on X86_64 && NUMA && ACPI && PCI 1290 select ACPI_NUMA 1291 ---help--- 1292 Enable ACPI SRAT based node topology detection. 1293 1294# Some NUMA nodes have memory ranges that span 1295# other nodes. Even though a pfn is valid and 1296# between a node's start and end pfns, it may not 1297# reside on that node. See memmap_init_zone() 1298# for details. 1299config NODES_SPAN_OTHER_NODES 1300 def_bool y 1301 depends on X86_64_ACPI_NUMA 1302 1303config NUMA_EMU 1304 bool "NUMA emulation" 1305 depends on NUMA 1306 ---help--- 1307 Enable NUMA emulation. A flat machine will be split 1308 into virtual nodes when booted with "numa=fake=N", where N is the 1309 number of nodes. This is only useful for debugging. 1310 1311config NODES_SHIFT 1312 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1313 range 1 10 1314 default "10" if MAXSMP 1315 default "6" if X86_64 1316 default "4" if X86_NUMAQ 1317 default "3" 1318 depends on NEED_MULTIPLE_NODES 1319 ---help--- 1320 Specify the maximum number of NUMA Nodes available on the target 1321 system. Increases memory reserved to accommodate various tables. 1322 1323config ARCH_HAVE_MEMORY_PRESENT 1324 def_bool y 1325 depends on X86_32 && DISCONTIGMEM 1326 1327config NEED_NODE_MEMMAP_SIZE 1328 def_bool y 1329 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1330 1331config ARCH_FLATMEM_ENABLE 1332 def_bool y 1333 depends on X86_32 && !NUMA 1334 1335config ARCH_DISCONTIGMEM_ENABLE 1336 def_bool y 1337 depends on NUMA && X86_32 1338 1339config ARCH_DISCONTIGMEM_DEFAULT 1340 def_bool y 1341 depends on NUMA && X86_32 1342 1343config ARCH_SPARSEMEM_ENABLE 1344 def_bool y 1345 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1346 select SPARSEMEM_STATIC if X86_32 1347 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1348 1349config ARCH_SPARSEMEM_DEFAULT 1350 def_bool y 1351 depends on X86_64 1352 1353config ARCH_SELECT_MEMORY_MODEL 1354 def_bool y 1355 depends on ARCH_SPARSEMEM_ENABLE 1356 1357config ARCH_MEMORY_PROBE 1358 bool "Enable sysfs memory/probe interface" 1359 depends on X86_64 && MEMORY_HOTPLUG 1360 help 1361 This option enables a sysfs memory/probe interface for testing. 1362 See Documentation/memory-hotplug.txt for more information. 1363 If you are unsure how to answer this question, answer N. 1364 1365config ARCH_PROC_KCORE_TEXT 1366 def_bool y 1367 depends on X86_64 && PROC_KCORE 1368 1369config ILLEGAL_POINTER_VALUE 1370 hex 1371 default 0 if X86_32 1372 default 0xdead000000000000 if X86_64 1373 1374source "mm/Kconfig" 1375 1376config HIGHPTE 1377 bool "Allocate 3rd-level pagetables from highmem" 1378 depends on HIGHMEM 1379 ---help--- 1380 The VM uses one page table entry for each page of physical memory. 1381 For systems with a lot of RAM, this can be wasteful of precious 1382 low memory. Setting this option will put user-space page table 1383 entries in high memory. 1384 1385config X86_CHECK_BIOS_CORRUPTION 1386 bool "Check for low memory corruption" 1387 ---help--- 1388 Periodically check for memory corruption in low memory, which 1389 is suspected to be caused by BIOS. Even when enabled in the 1390 configuration, it is disabled at runtime. Enable it by 1391 setting "memory_corruption_check=1" on the kernel command 1392 line. By default it scans the low 64k of memory every 60 1393 seconds; see the memory_corruption_check_size and 1394 memory_corruption_check_period parameters in 1395 Documentation/kernel-parameters.txt to adjust this. 1396 1397 When enabled with the default parameters, this option has 1398 almost no overhead, as it reserves a relatively small amount 1399 of memory and scans it infrequently. It both detects corruption 1400 and prevents it from affecting the running system. 1401 1402 It is, however, intended as a diagnostic tool; if repeatable 1403 BIOS-originated corruption always affects the same memory, 1404 you can use memmap= to prevent the kernel from using that 1405 memory. 1406 1407config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1408 bool "Set the default setting of memory_corruption_check" 1409 depends on X86_CHECK_BIOS_CORRUPTION 1410 default y 1411 ---help--- 1412 Set whether the default state of memory_corruption_check is 1413 on or off. 1414 1415config X86_RESERVE_LOW 1416 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1417 default 64 1418 range 4 640 1419 ---help--- 1420 Specify the amount of low memory to reserve for the BIOS. 1421 1422 The first page contains BIOS data structures that the kernel 1423 must not use, so that page must always be reserved. 1424 1425 By default we reserve the first 64K of physical RAM, as a 1426 number of BIOSes are known to corrupt that memory range 1427 during events such as suspend/resume or monitor cable 1428 insertion, so it must not be used by the kernel. 1429 1430 You can set this to 4 if you are absolutely sure that you 1431 trust the BIOS to get all its memory reservations and usages 1432 right. If you know your BIOS have problems beyond the 1433 default 64K area, you can set this to 640 to avoid using the 1434 entire low memory range. 1435 1436 If you have doubts about the BIOS (e.g. suspend/resume does 1437 not work or there's kernel crashes after certain hardware 1438 hotplug events) then you might want to enable 1439 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1440 typical corruption patterns. 1441 1442 Leave this to the default value of 64 if you are unsure. 1443 1444config MATH_EMULATION 1445 bool 1446 prompt "Math emulation" if X86_32 1447 ---help--- 1448 Linux can emulate a math coprocessor (used for floating point 1449 operations) if you don't have one. 486DX and Pentium processors have 1450 a math coprocessor built in, 486SX and 386 do not, unless you added 1451 a 487DX or 387, respectively. (The messages during boot time can 1452 give you some hints here ["man dmesg"].) Everyone needs either a 1453 coprocessor or this emulation. 1454 1455 If you don't have a math coprocessor, you need to say Y here; if you 1456 say Y here even though you have a coprocessor, the coprocessor will 1457 be used nevertheless. (This behavior can be changed with the kernel 1458 command line option "no387", which comes handy if your coprocessor 1459 is broken. Try "man bootparam" or see the documentation of your boot 1460 loader (lilo or loadlin) about how to pass options to the kernel at 1461 boot time.) This means that it is a good idea to say Y here if you 1462 intend to use this kernel on different machines. 1463 1464 More information about the internals of the Linux math coprocessor 1465 emulation can be found in <file:arch/x86/math-emu/README>. 1466 1467 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1468 kernel, it won't hurt. 1469 1470config MTRR 1471 def_bool y 1472 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1473 ---help--- 1474 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1475 the Memory Type Range Registers (MTRRs) may be used to control 1476 processor access to memory ranges. This is most useful if you have 1477 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1478 allows bus write transfers to be combined into a larger transfer 1479 before bursting over the PCI/AGP bus. This can increase performance 1480 of image write operations 2.5 times or more. Saying Y here creates a 1481 /proc/mtrr file which may be used to manipulate your processor's 1482 MTRRs. Typically the X server should use this. 1483 1484 This code has a reasonably generic interface so that similar 1485 control registers on other processors can be easily supported 1486 as well: 1487 1488 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1489 Registers (ARRs) which provide a similar functionality to MTRRs. For 1490 these, the ARRs are used to emulate the MTRRs. 1491 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1492 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1493 write-combining. All of these processors are supported by this code 1494 and it makes sense to say Y here if you have one of them. 1495 1496 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1497 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1498 can lead to all sorts of problems, so it's good to say Y here. 1499 1500 You can safely say Y even if your machine doesn't have MTRRs, you'll 1501 just add about 9 KB to your kernel. 1502 1503 See <file:Documentation/x86/mtrr.txt> for more information. 1504 1505config MTRR_SANITIZER 1506 def_bool y 1507 prompt "MTRR cleanup support" 1508 depends on MTRR 1509 ---help--- 1510 Convert MTRR layout from continuous to discrete, so X drivers can 1511 add writeback entries. 1512 1513 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1514 The largest mtrr entry size for a continuous block can be set with 1515 mtrr_chunk_size. 1516 1517 If unsure, say Y. 1518 1519config MTRR_SANITIZER_ENABLE_DEFAULT 1520 int "MTRR cleanup enable value (0-1)" 1521 range 0 1 1522 default "0" 1523 depends on MTRR_SANITIZER 1524 ---help--- 1525 Enable mtrr cleanup default value 1526 1527config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1528 int "MTRR cleanup spare reg num (0-7)" 1529 range 0 7 1530 default "1" 1531 depends on MTRR_SANITIZER 1532 ---help--- 1533 mtrr cleanup spare entries default, it can be changed via 1534 mtrr_spare_reg_nr=N on the kernel command line. 1535 1536config X86_PAT 1537 def_bool y 1538 prompt "x86 PAT support" if EXPERT 1539 depends on MTRR 1540 ---help--- 1541 Use PAT attributes to setup page level cache control. 1542 1543 PATs are the modern equivalents of MTRRs and are much more 1544 flexible than MTRRs. 1545 1546 Say N here if you see bootup problems (boot crash, boot hang, 1547 spontaneous reboots) or a non-working video driver. 1548 1549 If unsure, say Y. 1550 1551config ARCH_USES_PG_UNCACHED 1552 def_bool y 1553 depends on X86_PAT 1554 1555config ARCH_RANDOM 1556 def_bool y 1557 prompt "x86 architectural random number generator" if EXPERT 1558 ---help--- 1559 Enable the x86 architectural RDRAND instruction 1560 (Intel Bull Mountain technology) to generate random numbers. 1561 If supported, this is a high bandwidth, cryptographically 1562 secure hardware random number generator. 1563 1564config X86_SMAP 1565 def_bool y 1566 prompt "Supervisor Mode Access Prevention" if EXPERT 1567 ---help--- 1568 Supervisor Mode Access Prevention (SMAP) is a security 1569 feature in newer Intel processors. There is a small 1570 performance cost if this enabled and turned on; there is 1571 also a small increase in the kernel size if this is enabled. 1572 1573 If unsure, say Y. 1574 1575config EFI 1576 bool "EFI runtime service support" 1577 depends on ACPI 1578 select UCS2_STRING 1579 ---help--- 1580 This enables the kernel to use EFI runtime services that are 1581 available (such as the EFI variable services). 1582 1583 This option is only useful on systems that have EFI firmware. 1584 In addition, you should use the latest ELILO loader available 1585 at <http://elilo.sourceforge.net> in order to take advantage 1586 of EFI runtime services. However, even with this option, the 1587 resultant kernel should continue to boot on existing non-EFI 1588 platforms. 1589 1590config EFI_STUB 1591 bool "EFI stub support" 1592 depends on EFI 1593 ---help--- 1594 This kernel feature allows a bzImage to be loaded directly 1595 by EFI firmware without the use of a bootloader. 1596 1597 See Documentation/x86/efi-stub.txt for more information. 1598 1599config SECCOMP 1600 def_bool y 1601 prompt "Enable seccomp to safely compute untrusted bytecode" 1602 ---help--- 1603 This kernel feature is useful for number crunching applications 1604 that may need to compute untrusted bytecode during their 1605 execution. By using pipes or other transports made available to 1606 the process as file descriptors supporting the read/write 1607 syscalls, it's possible to isolate those applications in 1608 their own address space using seccomp. Once seccomp is 1609 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1610 and the task is only allowed to execute a few safe syscalls 1611 defined by each seccomp mode. 1612 1613 If unsure, say Y. Only embedded should say N here. 1614 1615config CC_STACKPROTECTOR 1616 bool "Enable -fstack-protector buffer overflow detection" 1617 ---help--- 1618 This option turns on the -fstack-protector GCC feature. This 1619 feature puts, at the beginning of functions, a canary value on 1620 the stack just before the return address, and validates 1621 the value just before actually returning. Stack based buffer 1622 overflows (that need to overwrite this return address) now also 1623 overwrite the canary, which gets detected and the attack is then 1624 neutralized via a kernel panic. 1625 1626 This feature requires gcc version 4.2 or above, or a distribution 1627 gcc with the feature backported. Older versions are automatically 1628 detected and for those versions, this configuration option is 1629 ignored. (and a warning is printed during bootup) 1630 1631source kernel/Kconfig.hz 1632 1633config KEXEC 1634 bool "kexec system call" 1635 ---help--- 1636 kexec is a system call that implements the ability to shutdown your 1637 current kernel, and to start another kernel. It is like a reboot 1638 but it is independent of the system firmware. And like a reboot 1639 you can start any kernel with it, not just Linux. 1640 1641 The name comes from the similarity to the exec system call. 1642 1643 It is an ongoing process to be certain the hardware in a machine 1644 is properly shutdown, so do not be surprised if this code does not 1645 initially work for you. As of this writing the exact hardware 1646 interface is strongly in flux, so no good recommendation can be 1647 made. 1648 1649config CRASH_DUMP 1650 bool "kernel crash dumps" 1651 depends on X86_64 || (X86_32 && HIGHMEM) 1652 ---help--- 1653 Generate crash dump after being started by kexec. 1654 This should be normally only set in special crash dump kernels 1655 which are loaded in the main kernel with kexec-tools into 1656 a specially reserved region and then later executed after 1657 a crash by kdump/kexec. The crash dump kernel must be compiled 1658 to a memory address not used by the main kernel or BIOS using 1659 PHYSICAL_START, or it must be built as a relocatable image 1660 (CONFIG_RELOCATABLE=y). 1661 For more details see Documentation/kdump/kdump.txt 1662 1663config KEXEC_JUMP 1664 bool "kexec jump" 1665 depends on KEXEC && HIBERNATION 1666 ---help--- 1667 Jump between original kernel and kexeced kernel and invoke 1668 code in physical address mode via KEXEC 1669 1670config PHYSICAL_START 1671 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1672 default "0x1000000" 1673 ---help--- 1674 This gives the physical address where the kernel is loaded. 1675 1676 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1677 bzImage will decompress itself to above physical address and 1678 run from there. Otherwise, bzImage will run from the address where 1679 it has been loaded by the boot loader and will ignore above physical 1680 address. 1681 1682 In normal kdump cases one does not have to set/change this option 1683 as now bzImage can be compiled as a completely relocatable image 1684 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1685 address. This option is mainly useful for the folks who don't want 1686 to use a bzImage for capturing the crash dump and want to use a 1687 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1688 to be specifically compiled to run from a specific memory area 1689 (normally a reserved region) and this option comes handy. 1690 1691 So if you are using bzImage for capturing the crash dump, 1692 leave the value here unchanged to 0x1000000 and set 1693 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1694 for capturing the crash dump change this value to start of 1695 the reserved region. In other words, it can be set based on 1696 the "X" value as specified in the "crashkernel=YM@XM" 1697 command line boot parameter passed to the panic-ed 1698 kernel. Please take a look at Documentation/kdump/kdump.txt 1699 for more details about crash dumps. 1700 1701 Usage of bzImage for capturing the crash dump is recommended as 1702 one does not have to build two kernels. Same kernel can be used 1703 as production kernel and capture kernel. Above option should have 1704 gone away after relocatable bzImage support is introduced. But it 1705 is present because there are users out there who continue to use 1706 vmlinux for dump capture. This option should go away down the 1707 line. 1708 1709 Don't change this unless you know what you are doing. 1710 1711config RELOCATABLE 1712 bool "Build a relocatable kernel" 1713 default y 1714 ---help--- 1715 This builds a kernel image that retains relocation information 1716 so it can be loaded someplace besides the default 1MB. 1717 The relocations tend to make the kernel binary about 10% larger, 1718 but are discarded at runtime. 1719 1720 One use is for the kexec on panic case where the recovery kernel 1721 must live at a different physical address than the primary 1722 kernel. 1723 1724 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1725 it has been loaded at and the compile time physical address 1726 (CONFIG_PHYSICAL_START) is ignored. 1727 1728# Relocation on x86-32 needs some additional build support 1729config X86_NEED_RELOCS 1730 def_bool y 1731 depends on X86_32 && RELOCATABLE 1732 1733config PHYSICAL_ALIGN 1734 hex "Alignment value to which kernel should be aligned" 1735 default "0x1000000" 1736 range 0x2000 0x1000000 if X86_32 1737 range 0x200000 0x1000000 if X86_64 1738 ---help--- 1739 This value puts the alignment restrictions on physical address 1740 where kernel is loaded and run from. Kernel is compiled for an 1741 address which meets above alignment restriction. 1742 1743 If bootloader loads the kernel at a non-aligned address and 1744 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1745 address aligned to above value and run from there. 1746 1747 If bootloader loads the kernel at a non-aligned address and 1748 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1749 load address and decompress itself to the address it has been 1750 compiled for and run from there. The address for which kernel is 1751 compiled already meets above alignment restrictions. Hence the 1752 end result is that kernel runs from a physical address meeting 1753 above alignment restrictions. 1754 1755 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1756 this value must be a multiple of 0x200000. 1757 1758 Don't change this unless you know what you are doing. 1759 1760config HOTPLUG_CPU 1761 bool "Support for hot-pluggable CPUs" 1762 depends on SMP 1763 ---help--- 1764 Say Y here to allow turning CPUs off and on. CPUs can be 1765 controlled through /sys/devices/system/cpu. 1766 ( Note: power management support will enable this option 1767 automatically on SMP systems. ) 1768 Say N if you want to disable CPU hotplug. 1769 1770config BOOTPARAM_HOTPLUG_CPU0 1771 bool "Set default setting of cpu0_hotpluggable" 1772 default n 1773 depends on HOTPLUG_CPU 1774 ---help--- 1775 Set whether default state of cpu0_hotpluggable is on or off. 1776 1777 Say Y here to enable CPU0 hotplug by default. If this switch 1778 is turned on, there is no need to give cpu0_hotplug kernel 1779 parameter and the CPU0 hotplug feature is enabled by default. 1780 1781 Please note: there are two known CPU0 dependencies if you want 1782 to enable the CPU0 hotplug feature either by this switch or by 1783 cpu0_hotplug kernel parameter. 1784 1785 First, resume from hibernate or suspend always starts from CPU0. 1786 So hibernate and suspend are prevented if CPU0 is offline. 1787 1788 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1789 offline if any interrupt can not migrate out of CPU0. There may 1790 be other CPU0 dependencies. 1791 1792 Please make sure the dependencies are under your control before 1793 you enable this feature. 1794 1795 Say N if you don't want to enable CPU0 hotplug feature by default. 1796 You still can enable the CPU0 hotplug feature at boot by kernel 1797 parameter cpu0_hotplug. 1798 1799config DEBUG_HOTPLUG_CPU0 1800 def_bool n 1801 prompt "Debug CPU0 hotplug" 1802 depends on HOTPLUG_CPU 1803 ---help--- 1804 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 1805 soon as possible and boots up userspace with CPU0 offlined. User 1806 can online CPU0 back after boot time. 1807 1808 To debug CPU0 hotplug, you need to enable CPU0 offline/online 1809 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 1810 compilation or giving cpu0_hotplug kernel parameter at boot. 1811 1812 If unsure, say N. 1813 1814config COMPAT_VDSO 1815 def_bool y 1816 prompt "Compat VDSO support" 1817 depends on X86_32 || IA32_EMULATION 1818 ---help--- 1819 Map the 32-bit VDSO to the predictable old-style address too. 1820 1821 Say N here if you are running a sufficiently recent glibc 1822 version (2.3.3 or later), to remove the high-mapped 1823 VDSO mapping and to exclusively use the randomized VDSO. 1824 1825 If unsure, say Y. 1826 1827config CMDLINE_BOOL 1828 bool "Built-in kernel command line" 1829 ---help--- 1830 Allow for specifying boot arguments to the kernel at 1831 build time. On some systems (e.g. embedded ones), it is 1832 necessary or convenient to provide some or all of the 1833 kernel boot arguments with the kernel itself (that is, 1834 to not rely on the boot loader to provide them.) 1835 1836 To compile command line arguments into the kernel, 1837 set this option to 'Y', then fill in the 1838 the boot arguments in CONFIG_CMDLINE. 1839 1840 Systems with fully functional boot loaders (i.e. non-embedded) 1841 should leave this option set to 'N'. 1842 1843config CMDLINE 1844 string "Built-in kernel command string" 1845 depends on CMDLINE_BOOL 1846 default "" 1847 ---help--- 1848 Enter arguments here that should be compiled into the kernel 1849 image and used at boot time. If the boot loader provides a 1850 command line at boot time, it is appended to this string to 1851 form the full kernel command line, when the system boots. 1852 1853 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1854 change this behavior. 1855 1856 In most cases, the command line (whether built-in or provided 1857 by the boot loader) should specify the device for the root 1858 file system. 1859 1860config CMDLINE_OVERRIDE 1861 bool "Built-in command line overrides boot loader arguments" 1862 depends on CMDLINE_BOOL 1863 ---help--- 1864 Set this option to 'Y' to have the kernel ignore the boot loader 1865 command line, and use ONLY the built-in command line. 1866 1867 This is used to work around broken boot loaders. This should 1868 be set to 'N' under normal conditions. 1869 1870endmenu 1871 1872config ARCH_ENABLE_MEMORY_HOTPLUG 1873 def_bool y 1874 depends on X86_64 || (X86_32 && HIGHMEM) 1875 1876config ARCH_ENABLE_MEMORY_HOTREMOVE 1877 def_bool y 1878 depends on MEMORY_HOTPLUG 1879 1880config USE_PERCPU_NUMA_NODE_ID 1881 def_bool y 1882 depends on NUMA 1883 1884menu "Power management and ACPI options" 1885 1886config ARCH_HIBERNATION_HEADER 1887 def_bool y 1888 depends on X86_64 && HIBERNATION 1889 1890source "kernel/power/Kconfig" 1891 1892source "drivers/acpi/Kconfig" 1893 1894source "drivers/sfi/Kconfig" 1895 1896config X86_APM_BOOT 1897 def_bool y 1898 depends on APM 1899 1900menuconfig APM 1901 tristate "APM (Advanced Power Management) BIOS support" 1902 depends on X86_32 && PM_SLEEP 1903 ---help--- 1904 APM is a BIOS specification for saving power using several different 1905 techniques. This is mostly useful for battery powered laptops with 1906 APM compliant BIOSes. If you say Y here, the system time will be 1907 reset after a RESUME operation, the /proc/apm device will provide 1908 battery status information, and user-space programs will receive 1909 notification of APM "events" (e.g. battery status change). 1910 1911 If you select "Y" here, you can disable actual use of the APM 1912 BIOS by passing the "apm=off" option to the kernel at boot time. 1913 1914 Note that the APM support is almost completely disabled for 1915 machines with more than one CPU. 1916 1917 In order to use APM, you will need supporting software. For location 1918 and more information, read <file:Documentation/power/apm-acpi.txt> 1919 and the Battery Powered Linux mini-HOWTO, available from 1920 <http://www.tldp.org/docs.html#howto>. 1921 1922 This driver does not spin down disk drives (see the hdparm(8) 1923 manpage ("man 8 hdparm") for that), and it doesn't turn off 1924 VESA-compliant "green" monitors. 1925 1926 This driver does not support the TI 4000M TravelMate and the ACER 1927 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1928 desktop machines also don't have compliant BIOSes, and this driver 1929 may cause those machines to panic during the boot phase. 1930 1931 Generally, if you don't have a battery in your machine, there isn't 1932 much point in using this driver and you should say N. If you get 1933 random kernel OOPSes or reboots that don't seem to be related to 1934 anything, try disabling/enabling this option (or disabling/enabling 1935 APM in your BIOS). 1936 1937 Some other things you should try when experiencing seemingly random, 1938 "weird" problems: 1939 1940 1) make sure that you have enough swap space and that it is 1941 enabled. 1942 2) pass the "no-hlt" option to the kernel 1943 3) switch on floating point emulation in the kernel and pass 1944 the "no387" option to the kernel 1945 4) pass the "floppy=nodma" option to the kernel 1946 5) pass the "mem=4M" option to the kernel (thereby disabling 1947 all but the first 4 MB of RAM) 1948 6) make sure that the CPU is not over clocked. 1949 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1950 8) disable the cache from your BIOS settings 1951 9) install a fan for the video card or exchange video RAM 1952 10) install a better fan for the CPU 1953 11) exchange RAM chips 1954 12) exchange the motherboard. 1955 1956 To compile this driver as a module, choose M here: the 1957 module will be called apm. 1958 1959if APM 1960 1961config APM_IGNORE_USER_SUSPEND 1962 bool "Ignore USER SUSPEND" 1963 ---help--- 1964 This option will ignore USER SUSPEND requests. On machines with a 1965 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1966 series notebooks, it is necessary to say Y because of a BIOS bug. 1967 1968config APM_DO_ENABLE 1969 bool "Enable PM at boot time" 1970 ---help--- 1971 Enable APM features at boot time. From page 36 of the APM BIOS 1972 specification: "When disabled, the APM BIOS does not automatically 1973 power manage devices, enter the Standby State, enter the Suspend 1974 State, or take power saving steps in response to CPU Idle calls." 1975 This driver will make CPU Idle calls when Linux is idle (unless this 1976 feature is turned off -- see "Do CPU IDLE calls", below). This 1977 should always save battery power, but more complicated APM features 1978 will be dependent on your BIOS implementation. You may need to turn 1979 this option off if your computer hangs at boot time when using APM 1980 support, or if it beeps continuously instead of suspending. Turn 1981 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1982 T400CDT. This is off by default since most machines do fine without 1983 this feature. 1984 1985config APM_CPU_IDLE 1986 depends on CPU_IDLE 1987 bool "Make CPU Idle calls when idle" 1988 ---help--- 1989 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1990 On some machines, this can activate improved power savings, such as 1991 a slowed CPU clock rate, when the machine is idle. These idle calls 1992 are made after the idle loop has run for some length of time (e.g., 1993 333 mS). On some machines, this will cause a hang at boot time or 1994 whenever the CPU becomes idle. (On machines with more than one CPU, 1995 this option does nothing.) 1996 1997config APM_DISPLAY_BLANK 1998 bool "Enable console blanking using APM" 1999 ---help--- 2000 Enable console blanking using the APM. Some laptops can use this to 2001 turn off the LCD backlight when the screen blanker of the Linux 2002 virtual console blanks the screen. Note that this is only used by 2003 the virtual console screen blanker, and won't turn off the backlight 2004 when using the X Window system. This also doesn't have anything to 2005 do with your VESA-compliant power-saving monitor. Further, this 2006 option doesn't work for all laptops -- it might not turn off your 2007 backlight at all, or it might print a lot of errors to the console, 2008 especially if you are using gpm. 2009 2010config APM_ALLOW_INTS 2011 bool "Allow interrupts during APM BIOS calls" 2012 ---help--- 2013 Normally we disable external interrupts while we are making calls to 2014 the APM BIOS as a measure to lessen the effects of a badly behaving 2015 BIOS implementation. The BIOS should reenable interrupts if it 2016 needs to. Unfortunately, some BIOSes do not -- especially those in 2017 many of the newer IBM Thinkpads. If you experience hangs when you 2018 suspend, try setting this to Y. Otherwise, say N. 2019 2020endif # APM 2021 2022source "drivers/cpufreq/Kconfig" 2023 2024source "drivers/cpuidle/Kconfig" 2025 2026source "drivers/idle/Kconfig" 2027 2028endmenu 2029 2030 2031menu "Bus options (PCI etc.)" 2032 2033config PCI 2034 bool "PCI support" 2035 default y 2036 ---help--- 2037 Find out whether you have a PCI motherboard. PCI is the name of a 2038 bus system, i.e. the way the CPU talks to the other stuff inside 2039 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2040 VESA. If you have PCI, say Y, otherwise N. 2041 2042choice 2043 prompt "PCI access mode" 2044 depends on X86_32 && PCI 2045 default PCI_GOANY 2046 ---help--- 2047 On PCI systems, the BIOS can be used to detect the PCI devices and 2048 determine their configuration. However, some old PCI motherboards 2049 have BIOS bugs and may crash if this is done. Also, some embedded 2050 PCI-based systems don't have any BIOS at all. Linux can also try to 2051 detect the PCI hardware directly without using the BIOS. 2052 2053 With this option, you can specify how Linux should detect the 2054 PCI devices. If you choose "BIOS", the BIOS will be used, 2055 if you choose "Direct", the BIOS won't be used, and if you 2056 choose "MMConfig", then PCI Express MMCONFIG will be used. 2057 If you choose "Any", the kernel will try MMCONFIG, then the 2058 direct access method and falls back to the BIOS if that doesn't 2059 work. If unsure, go with the default, which is "Any". 2060 2061config PCI_GOBIOS 2062 bool "BIOS" 2063 2064config PCI_GOMMCONFIG 2065 bool "MMConfig" 2066 2067config PCI_GODIRECT 2068 bool "Direct" 2069 2070config PCI_GOOLPC 2071 bool "OLPC XO-1" 2072 depends on OLPC 2073 2074config PCI_GOANY 2075 bool "Any" 2076 2077endchoice 2078 2079config PCI_BIOS 2080 def_bool y 2081 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2082 2083# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2084config PCI_DIRECT 2085 def_bool y 2086 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2087 2088config PCI_MMCONFIG 2089 def_bool y 2090 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2091 2092config PCI_OLPC 2093 def_bool y 2094 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2095 2096config PCI_XEN 2097 def_bool y 2098 depends on PCI && XEN 2099 select SWIOTLB_XEN 2100 2101config PCI_DOMAINS 2102 def_bool y 2103 depends on PCI 2104 2105config PCI_MMCONFIG 2106 bool "Support mmconfig PCI config space access" 2107 depends on X86_64 && PCI && ACPI 2108 2109config PCI_CNB20LE_QUIRK 2110 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2111 depends on PCI 2112 help 2113 Read the PCI windows out of the CNB20LE host bridge. This allows 2114 PCI hotplug to work on systems with the CNB20LE chipset which do 2115 not have ACPI. 2116 2117 There's no public spec for this chipset, and this functionality 2118 is known to be incomplete. 2119 2120 You should say N unless you know you need this. 2121 2122source "drivers/pci/pcie/Kconfig" 2123 2124source "drivers/pci/Kconfig" 2125 2126# x86_64 have no ISA slots, but can have ISA-style DMA. 2127config ISA_DMA_API 2128 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2129 default y 2130 help 2131 Enables ISA-style DMA support for devices requiring such controllers. 2132 If unsure, say Y. 2133 2134if X86_32 2135 2136config ISA 2137 bool "ISA support" 2138 ---help--- 2139 Find out whether you have ISA slots on your motherboard. ISA is the 2140 name of a bus system, i.e. the way the CPU talks to the other stuff 2141 inside your box. Other bus systems are PCI, EISA, MicroChannel 2142 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2143 newer boards don't support it. If you have ISA, say Y, otherwise N. 2144 2145config EISA 2146 bool "EISA support" 2147 depends on ISA 2148 ---help--- 2149 The Extended Industry Standard Architecture (EISA) bus was 2150 developed as an open alternative to the IBM MicroChannel bus. 2151 2152 The EISA bus provided some of the features of the IBM MicroChannel 2153 bus while maintaining backward compatibility with cards made for 2154 the older ISA bus. The EISA bus saw limited use between 1988 and 2155 1995 when it was made obsolete by the PCI bus. 2156 2157 Say Y here if you are building a kernel for an EISA-based machine. 2158 2159 Otherwise, say N. 2160 2161source "drivers/eisa/Kconfig" 2162 2163config SCx200 2164 tristate "NatSemi SCx200 support" 2165 ---help--- 2166 This provides basic support for National Semiconductor's 2167 (now AMD's) Geode processors. The driver probes for the 2168 PCI-IDs of several on-chip devices, so its a good dependency 2169 for other scx200_* drivers. 2170 2171 If compiled as a module, the driver is named scx200. 2172 2173config SCx200HR_TIMER 2174 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2175 depends on SCx200 2176 default y 2177 ---help--- 2178 This driver provides a clocksource built upon the on-chip 2179 27MHz high-resolution timer. Its also a workaround for 2180 NSC Geode SC-1100's buggy TSC, which loses time when the 2181 processor goes idle (as is done by the scheduler). The 2182 other workaround is idle=poll boot option. 2183 2184config OLPC 2185 bool "One Laptop Per Child support" 2186 depends on !X86_PAE 2187 select GPIOLIB 2188 select OF 2189 select OF_PROMTREE 2190 select IRQ_DOMAIN 2191 ---help--- 2192 Add support for detecting the unique features of the OLPC 2193 XO hardware. 2194 2195config OLPC_XO1_PM 2196 bool "OLPC XO-1 Power Management" 2197 depends on OLPC && MFD_CS5535 && PM_SLEEP 2198 select MFD_CORE 2199 ---help--- 2200 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2201 2202config OLPC_XO1_RTC 2203 bool "OLPC XO-1 Real Time Clock" 2204 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2205 ---help--- 2206 Add support for the XO-1 real time clock, which can be used as a 2207 programmable wakeup source. 2208 2209config OLPC_XO1_SCI 2210 bool "OLPC XO-1 SCI extras" 2211 depends on OLPC && OLPC_XO1_PM 2212 depends on INPUT=y 2213 select POWER_SUPPLY 2214 select GPIO_CS5535 2215 select MFD_CORE 2216 ---help--- 2217 Add support for SCI-based features of the OLPC XO-1 laptop: 2218 - EC-driven system wakeups 2219 - Power button 2220 - Ebook switch 2221 - Lid switch 2222 - AC adapter status updates 2223 - Battery status updates 2224 2225config OLPC_XO15_SCI 2226 bool "OLPC XO-1.5 SCI extras" 2227 depends on OLPC && ACPI 2228 select POWER_SUPPLY 2229 ---help--- 2230 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2231 - EC-driven system wakeups 2232 - AC adapter status updates 2233 - Battery status updates 2234 2235config ALIX 2236 bool "PCEngines ALIX System Support (LED setup)" 2237 select GPIOLIB 2238 ---help--- 2239 This option enables system support for the PCEngines ALIX. 2240 At present this just sets up LEDs for GPIO control on 2241 ALIX2/3/6 boards. However, other system specific setup should 2242 get added here. 2243 2244 Note: You must still enable the drivers for GPIO and LED support 2245 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2246 2247 Note: You have to set alix.force=1 for boards with Award BIOS. 2248 2249config NET5501 2250 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2251 select GPIOLIB 2252 ---help--- 2253 This option enables system support for the Soekris Engineering net5501. 2254 2255config GEOS 2256 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2257 select GPIOLIB 2258 depends on DMI 2259 ---help--- 2260 This option enables system support for the Traverse Technologies GEOS. 2261 2262config TS5500 2263 bool "Technologic Systems TS-5500 platform support" 2264 depends on MELAN 2265 select CHECK_SIGNATURE 2266 select NEW_LEDS 2267 select LEDS_CLASS 2268 ---help--- 2269 This option enables system support for the Technologic Systems TS-5500. 2270 2271endif # X86_32 2272 2273config AMD_NB 2274 def_bool y 2275 depends on CPU_SUP_AMD && PCI 2276 2277source "drivers/pcmcia/Kconfig" 2278 2279source "drivers/pci/hotplug/Kconfig" 2280 2281config RAPIDIO 2282 tristate "RapidIO support" 2283 depends on PCI 2284 default n 2285 help 2286 If enabled this option will include drivers and the core 2287 infrastructure code to support RapidIO interconnect devices. 2288 2289source "drivers/rapidio/Kconfig" 2290 2291config X86_SYSFB 2292 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2293 help 2294 Firmwares often provide initial graphics framebuffers so the BIOS, 2295 bootloader or kernel can show basic video-output during boot for 2296 user-guidance and debugging. Historically, x86 used the VESA BIOS 2297 Extensions and EFI-framebuffers for this, which are mostly limited 2298 to x86. 2299 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2300 framebuffers so the new generic system-framebuffer drivers can be 2301 used on x86. If the framebuffer is not compatible with the generic 2302 modes, it is adverticed as fallback platform framebuffer so legacy 2303 drivers like efifb, vesafb and uvesafb can pick it up. 2304 If this option is not selected, all system framebuffers are always 2305 marked as fallback platform framebuffers as usual. 2306 2307 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2308 not be able to pick up generic system framebuffers if this option 2309 is selected. You are highly encouraged to enable simplefb as 2310 replacement if you select this option. simplefb can correctly deal 2311 with generic system framebuffers. But you should still keep vesafb 2312 and others enabled as fallback if a system framebuffer is 2313 incompatible with simplefb. 2314 2315 If unsure, say Y. 2316 2317endmenu 2318 2319 2320menu "Executable file formats / Emulations" 2321 2322source "fs/Kconfig.binfmt" 2323 2324config IA32_EMULATION 2325 bool "IA32 Emulation" 2326 depends on X86_64 2327 select BINFMT_ELF 2328 select COMPAT_BINFMT_ELF 2329 select HAVE_UID16 2330 ---help--- 2331 Include code to run legacy 32-bit programs under a 2332 64-bit kernel. You should likely turn this on, unless you're 2333 100% sure that you don't have any 32-bit programs left. 2334 2335config IA32_AOUT 2336 tristate "IA32 a.out support" 2337 depends on IA32_EMULATION 2338 ---help--- 2339 Support old a.out binaries in the 32bit emulation. 2340 2341config X86_X32 2342 bool "x32 ABI for 64-bit mode" 2343 depends on X86_64 && IA32_EMULATION 2344 ---help--- 2345 Include code to run binaries for the x32 native 32-bit ABI 2346 for 64-bit processors. An x32 process gets access to the 2347 full 64-bit register file and wide data path while leaving 2348 pointers at 32 bits for smaller memory footprint. 2349 2350 You will need a recent binutils (2.22 or later) with 2351 elf32_x86_64 support enabled to compile a kernel with this 2352 option set. 2353 2354config COMPAT 2355 def_bool y 2356 depends on IA32_EMULATION || X86_X32 2357 select ARCH_WANT_OLD_COMPAT_IPC 2358 2359if COMPAT 2360config COMPAT_FOR_U64_ALIGNMENT 2361 def_bool y 2362 2363config SYSVIPC_COMPAT 2364 def_bool y 2365 depends on SYSVIPC 2366 2367config KEYS_COMPAT 2368 def_bool y 2369 depends on KEYS 2370endif 2371 2372endmenu 2373 2374 2375config HAVE_ATOMIC_IOMAP 2376 def_bool y 2377 depends on X86_32 2378 2379config X86_DEV_DMA_OPS 2380 bool 2381 depends on X86_64 || STA2X11 2382 2383config X86_DMA_REMAP 2384 bool 2385 depends on STA2X11 2386 2387source "net/Kconfig" 2388 2389source "drivers/Kconfig" 2390 2391source "drivers/firmware/Kconfig" 2392 2393source "fs/Kconfig" 2394 2395source "arch/x86/Kconfig.debug" 2396 2397source "security/Kconfig" 2398 2399source "crypto/Kconfig" 2400 2401source "arch/x86/kvm/Kconfig" 2402 2403source "lib/Kconfig" 2404