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 HAVE_AOUT if X86_32 27 select HAVE_UNSTABLE_SCHED_CLOCK 28 select ARCH_SUPPORTS_NUMA_BALANCING 29 select ARCH_SUPPORTS_INT128 if X86_64 30 select ARCH_WANTS_PROT_NUMA_PROT_NONE 31 select HAVE_IDE 32 select HAVE_OPROFILE 33 select HAVE_PCSPKR_PLATFORM 34 select HAVE_PERF_EVENTS 35 select HAVE_IOREMAP_PROT 36 select HAVE_KPROBES 37 select HAVE_MEMBLOCK 38 select HAVE_MEMBLOCK_NODE_MAP 39 select ARCH_DISCARD_MEMBLOCK 40 select ARCH_WANT_OPTIONAL_GPIOLIB 41 select ARCH_WANT_FRAME_POINTERS 42 select HAVE_DMA_ATTRS 43 select HAVE_DMA_CONTIGUOUS if !SWIOTLB 44 select HAVE_KRETPROBES 45 select HAVE_OPTPROBES 46 select HAVE_KPROBES_ON_FTRACE 47 select HAVE_FTRACE_MCOUNT_RECORD 48 select HAVE_FENTRY if X86_64 49 select HAVE_C_RECORDMCOUNT 50 select HAVE_DYNAMIC_FTRACE 51 select HAVE_DYNAMIC_FTRACE_WITH_REGS 52 select HAVE_FUNCTION_TRACER 53 select HAVE_FUNCTION_GRAPH_TRACER 54 select HAVE_FUNCTION_GRAPH_FP_TEST 55 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 56 select HAVE_SYSCALL_TRACEPOINTS 57 select SYSCTL_EXCEPTION_TRACE 58 select HAVE_KVM 59 select HAVE_ARCH_KGDB 60 select HAVE_ARCH_TRACEHOOK 61 select HAVE_GENERIC_DMA_COHERENT if X86_32 62 select HAVE_EFFICIENT_UNALIGNED_ACCESS 63 select USER_STACKTRACE_SUPPORT 64 select HAVE_REGS_AND_STACK_ACCESS_API 65 select HAVE_DMA_API_DEBUG 66 select HAVE_KERNEL_GZIP 67 select HAVE_KERNEL_BZIP2 68 select HAVE_KERNEL_LZMA 69 select HAVE_KERNEL_XZ 70 select HAVE_KERNEL_LZO 71 select HAVE_KERNEL_LZ4 72 select HAVE_HW_BREAKPOINT 73 select HAVE_MIXED_BREAKPOINTS_REGS 74 select PERF_EVENTS 75 select HAVE_PERF_EVENTS_NMI 76 select HAVE_PERF_REGS 77 select HAVE_PERF_USER_STACK_DUMP 78 select HAVE_DEBUG_KMEMLEAK 79 select ANON_INODES 80 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 81 select HAVE_CMPXCHG_LOCAL 82 select HAVE_CMPXCHG_DOUBLE 83 select HAVE_ARCH_KMEMCHECK 84 select HAVE_USER_RETURN_NOTIFIER 85 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 86 select HAVE_ARCH_JUMP_LABEL 87 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 88 select SPARSE_IRQ 89 select GENERIC_FIND_FIRST_BIT 90 select GENERIC_IRQ_PROBE 91 select GENERIC_PENDING_IRQ if SMP 92 select GENERIC_IRQ_SHOW 93 select GENERIC_CLOCKEVENTS_MIN_ADJUST 94 select IRQ_FORCED_THREADING 95 select HAVE_BPF_JIT if X86_64 96 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 97 select CLKEVT_I8253 98 select ARCH_HAVE_NMI_SAFE_CMPXCHG 99 select GENERIC_IOMAP 100 select DCACHE_WORD_ACCESS 101 select GENERIC_SMP_IDLE_THREAD 102 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 103 select HAVE_ARCH_SECCOMP_FILTER 104 select BUILDTIME_EXTABLE_SORT 105 select GENERIC_CMOS_UPDATE 106 select HAVE_ARCH_SOFT_DIRTY 107 select CLOCKSOURCE_WATCHDOG 108 select GENERIC_CLOCKEVENTS 109 select ARCH_CLOCKSOURCE_DATA if X86_64 110 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 111 select GENERIC_TIME_VSYSCALL if X86_64 112 select KTIME_SCALAR if X86_32 113 select GENERIC_STRNCPY_FROM_USER 114 select GENERIC_STRNLEN_USER 115 select HAVE_CONTEXT_TRACKING if X86_64 116 select HAVE_IRQ_TIME_ACCOUNTING 117 select VIRT_TO_BUS 118 select MODULES_USE_ELF_REL if X86_32 119 select MODULES_USE_ELF_RELA if X86_64 120 select CLONE_BACKWARDS if X86_32 121 select ARCH_USE_BUILTIN_BSWAP 122 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 123 select OLD_SIGACTION if X86_32 124 select COMPAT_OLD_SIGACTION if IA32_EMULATION 125 select RTC_LIB 126 select HAVE_DEBUG_STACKOVERFLOW 127 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 128 129config INSTRUCTION_DECODER 130 def_bool y 131 depends on KPROBES || PERF_EVENTS || UPROBES 132 133config OUTPUT_FORMAT 134 string 135 default "elf32-i386" if X86_32 136 default "elf64-x86-64" if X86_64 137 138config ARCH_DEFCONFIG 139 string 140 default "arch/x86/configs/i386_defconfig" if X86_32 141 default "arch/x86/configs/x86_64_defconfig" if X86_64 142 143config LOCKDEP_SUPPORT 144 def_bool y 145 146config STACKTRACE_SUPPORT 147 def_bool y 148 149config HAVE_LATENCYTOP_SUPPORT 150 def_bool y 151 152config MMU 153 def_bool y 154 155config SBUS 156 bool 157 158config NEED_DMA_MAP_STATE 159 def_bool y 160 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG 161 162config NEED_SG_DMA_LENGTH 163 def_bool y 164 165config GENERIC_ISA_DMA 166 def_bool y 167 depends on ISA_DMA_API 168 169config GENERIC_BUG 170 def_bool y 171 depends on BUG 172 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 173 174config GENERIC_BUG_RELATIVE_POINTERS 175 bool 176 177config GENERIC_HWEIGHT 178 def_bool y 179 180config ARCH_MAY_HAVE_PC_FDC 181 def_bool y 182 depends on ISA_DMA_API 183 184config RWSEM_XCHGADD_ALGORITHM 185 def_bool y 186 187config GENERIC_CALIBRATE_DELAY 188 def_bool y 189 190config ARCH_HAS_CPU_RELAX 191 def_bool y 192 193config ARCH_HAS_CACHE_LINE_SIZE 194 def_bool y 195 196config ARCH_HAS_CPU_AUTOPROBE 197 def_bool y 198 199config HAVE_SETUP_PER_CPU_AREA 200 def_bool y 201 202config NEED_PER_CPU_EMBED_FIRST_CHUNK 203 def_bool y 204 205config NEED_PER_CPU_PAGE_FIRST_CHUNK 206 def_bool y 207 208config ARCH_HIBERNATION_POSSIBLE 209 def_bool y 210 211config ARCH_SUSPEND_POSSIBLE 212 def_bool y 213 214config ARCH_WANT_HUGE_PMD_SHARE 215 def_bool y 216 217config ARCH_WANT_GENERAL_HUGETLB 218 def_bool y 219 220config ZONE_DMA32 221 bool 222 default X86_64 223 224config AUDIT_ARCH 225 bool 226 default X86_64 227 228config ARCH_SUPPORTS_OPTIMIZED_INLINING 229 def_bool y 230 231config ARCH_SUPPORTS_DEBUG_PAGEALLOC 232 def_bool y 233 234config HAVE_INTEL_TXT 235 def_bool y 236 depends on INTEL_IOMMU && ACPI 237 238config X86_32_SMP 239 def_bool y 240 depends on X86_32 && SMP 241 242config X86_64_SMP 243 def_bool y 244 depends on X86_64 && SMP 245 246config X86_HT 247 def_bool y 248 depends on SMP 249 250config X86_32_LAZY_GS 251 def_bool y 252 depends on X86_32 && !CC_STACKPROTECTOR 253 254config ARCH_HWEIGHT_CFLAGS 255 string 256 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 257 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_64 258 259config ARCH_SUPPORTS_UPROBES 260 def_bool y 261 262source "init/Kconfig" 263source "kernel/Kconfig.freezer" 264 265menu "Processor type and features" 266 267config ZONE_DMA 268 bool "DMA memory allocation support" if EXPERT 269 default y 270 help 271 DMA memory allocation support allows devices with less than 32-bit 272 addressing to allocate within the first 16MB of address space. 273 Disable if no such devices will be used. 274 275 If unsure, say Y. 276 277config SMP 278 bool "Symmetric multi-processing support" 279 ---help--- 280 This enables support for systems with more than one CPU. If you have 281 a system with only one CPU, like most personal computers, say N. If 282 you have a system with more than one CPU, say Y. 283 284 If you say N here, the kernel will run on single and multiprocessor 285 machines, but will use only one CPU of a multiprocessor machine. If 286 you say Y here, the kernel will run on many, but not all, 287 singleprocessor machines. On a singleprocessor machine, the kernel 288 will run faster if you say N here. 289 290 Note that if you say Y here and choose architecture "586" or 291 "Pentium" under "Processor family", the kernel will not work on 486 292 architectures. Similarly, multiprocessor kernels for the "PPro" 293 architecture may not work on all Pentium based boards. 294 295 People using multiprocessor machines who say Y here should also say 296 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 297 Management" code will be disabled if you say Y here. 298 299 See also <file:Documentation/x86/i386/IO-APIC.txt>, 300 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 301 <http://www.tldp.org/docs.html#howto>. 302 303 If you don't know what to do here, say N. 304 305config X86_X2APIC 306 bool "Support x2apic" 307 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 308 ---help--- 309 This enables x2apic support on CPUs that have this feature. 310 311 This allows 32-bit apic IDs (so it can support very large systems), 312 and accesses the local apic via MSRs not via mmio. 313 314 If you don't know what to do here, say N. 315 316config X86_MPPARSE 317 bool "Enable MPS table" if ACPI || SFI 318 default y 319 depends on X86_LOCAL_APIC 320 ---help--- 321 For old smp systems that do not have proper acpi support. Newer systems 322 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 323 324config X86_BIGSMP 325 bool "Support for big SMP systems with more than 8 CPUs" 326 depends on X86_32 && SMP 327 ---help--- 328 This option is needed for the systems that have more than 8 CPUs 329 330config GOLDFISH 331 def_bool y 332 depends on X86_GOLDFISH 333 334if X86_32 335config X86_EXTENDED_PLATFORM 336 bool "Support for extended (non-PC) x86 platforms" 337 default y 338 ---help--- 339 If you disable this option then the kernel will only support 340 standard PC platforms. (which covers the vast majority of 341 systems out there.) 342 343 If you enable this option then you'll be able to select support 344 for the following (non-PC) 32 bit x86 platforms: 345 Goldfish (Android emulator) 346 AMD Elan 347 NUMAQ (IBM/Sequent) 348 RDC R-321x SoC 349 SGI 320/540 (Visual Workstation) 350 STA2X11-based (e.g. Northville) 351 Summit/EXA (IBM x440) 352 Unisys ES7000 IA32 series 353 Moorestown MID devices 354 355 If you have one of these systems, or if you want to build a 356 generic distribution kernel, say Y here - otherwise say N. 357endif 358 359if X86_64 360config X86_EXTENDED_PLATFORM 361 bool "Support for extended (non-PC) x86 platforms" 362 default y 363 ---help--- 364 If you disable this option then the kernel will only support 365 standard PC platforms. (which covers the vast majority of 366 systems out there.) 367 368 If you enable this option then you'll be able to select support 369 for the following (non-PC) 64 bit x86 platforms: 370 Numascale NumaChip 371 ScaleMP vSMP 372 SGI Ultraviolet 373 374 If you have one of these systems, or if you want to build a 375 generic distribution kernel, say Y here - otherwise say N. 376endif 377# This is an alphabetically sorted list of 64 bit extended platforms 378# Please maintain the alphabetic order if and when there are additions 379config X86_NUMACHIP 380 bool "Numascale NumaChip" 381 depends on X86_64 382 depends on X86_EXTENDED_PLATFORM 383 depends on NUMA 384 depends on SMP 385 depends on X86_X2APIC 386 depends on PCI_MMCONFIG 387 ---help--- 388 Adds support for Numascale NumaChip large-SMP systems. Needed to 389 enable more than ~168 cores. 390 If you don't have one of these, you should say N here. 391 392config X86_VSMP 393 bool "ScaleMP vSMP" 394 select HYPERVISOR_GUEST 395 select PARAVIRT 396 depends on X86_64 && PCI 397 depends on X86_EXTENDED_PLATFORM 398 depends on SMP 399 ---help--- 400 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 401 supposed to run on these EM64T-based machines. Only choose this option 402 if you have one of these machines. 403 404config X86_UV 405 bool "SGI Ultraviolet" 406 depends on X86_64 407 depends on X86_EXTENDED_PLATFORM 408 depends on NUMA 409 depends on X86_X2APIC 410 ---help--- 411 This option is needed in order to support SGI Ultraviolet systems. 412 If you don't have one of these, you should say N here. 413 414# Following is an alphabetically sorted list of 32 bit extended platforms 415# Please maintain the alphabetic order if and when there are additions 416 417config X86_GOLDFISH 418 bool "Goldfish (Virtual Platform)" 419 depends on X86_32 420 depends on X86_EXTENDED_PLATFORM 421 ---help--- 422 Enable support for the Goldfish virtual platform used primarily 423 for Android development. Unless you are building for the Android 424 Goldfish emulator say N here. 425 426config X86_INTEL_CE 427 bool "CE4100 TV platform" 428 depends on PCI 429 depends on PCI_GODIRECT 430 depends on X86_32 431 depends on X86_EXTENDED_PLATFORM 432 select X86_REBOOTFIXUPS 433 select OF 434 select OF_EARLY_FLATTREE 435 select IRQ_DOMAIN 436 ---help--- 437 Select for the Intel CE media processor (CE4100) SOC. 438 This option compiles in support for the CE4100 SOC for settop 439 boxes and media devices. 440 441config X86_WANT_INTEL_MID 442 bool "Intel MID platform support" 443 depends on X86_32 444 depends on X86_EXTENDED_PLATFORM 445 ---help--- 446 Select to build a kernel capable of supporting Intel MID platform 447 systems which do not have the PCI legacy interfaces (Moorestown, 448 Medfield). If you are building for a PC class system say N here. 449 450if X86_WANT_INTEL_MID 451 452config X86_INTEL_MID 453 bool 454 455config X86_MDFLD 456 bool "Medfield MID platform" 457 depends on PCI 458 depends on PCI_GOANY 459 depends on X86_IO_APIC 460 select X86_INTEL_MID 461 select SFI 462 select DW_APB_TIMER 463 select APB_TIMER 464 select I2C 465 select SPI 466 select INTEL_SCU_IPC 467 select X86_PLATFORM_DEVICES 468 select MFD_INTEL_MSIC 469 ---help--- 470 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin 471 Internet Device(MID) platform. 472 Unlike standard x86 PCs, Medfield does not have many legacy devices 473 nor standard legacy replacement devices/features. e.g. Medfield does 474 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 475 476endif 477 478config X86_INTEL_LPSS 479 bool "Intel Low Power Subsystem Support" 480 depends on ACPI 481 select COMMON_CLK 482 select PINCTRL 483 ---help--- 484 Select to build support for Intel Low Power Subsystem such as 485 found on Intel Lynxpoint PCH. Selecting this option enables 486 things like clock tree (common clock framework) and pincontrol 487 which are needed by the LPSS peripheral drivers. 488 489config X86_RDC321X 490 bool "RDC R-321x SoC" 491 depends on X86_32 492 depends on X86_EXTENDED_PLATFORM 493 select M486 494 select X86_REBOOTFIXUPS 495 ---help--- 496 This option is needed for RDC R-321x system-on-chip, also known 497 as R-8610-(G). 498 If you don't have one of these chips, you should say N here. 499 500config X86_32_NON_STANDARD 501 bool "Support non-standard 32-bit SMP architectures" 502 depends on X86_32 && SMP 503 depends on X86_EXTENDED_PLATFORM 504 ---help--- 505 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, 506 STA2X11, default subarchitectures. It is intended for a generic 507 binary kernel. If you select them all, kernel will probe it 508 one by one and will fallback to default. 509 510# Alphabetically sorted list of Non standard 32 bit platforms 511 512config X86_NUMAQ 513 bool "NUMAQ (IBM/Sequent)" 514 depends on X86_32_NON_STANDARD 515 depends on PCI 516 select NUMA 517 select X86_MPPARSE 518 ---help--- 519 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 520 NUMA multiquad box. This changes the way that processors are 521 bootstrapped, and uses Clustered Logical APIC addressing mode instead 522 of Flat Logical. You will need a new lynxer.elf file to flash your 523 firmware with - send email to <Martin.Bligh@us.ibm.com>. 524 525config X86_SUPPORTS_MEMORY_FAILURE 526 def_bool y 527 # MCE code calls memory_failure(): 528 depends on X86_MCE 529 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 530 depends on !X86_NUMAQ 531 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 532 depends on X86_64 || !SPARSEMEM 533 select ARCH_SUPPORTS_MEMORY_FAILURE 534 535config X86_VISWS 536 bool "SGI 320/540 (Visual Workstation)" 537 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 538 depends on X86_32_NON_STANDARD 539 ---help--- 540 The SGI Visual Workstation series is an IA32-based workstation 541 based on SGI systems chips with some legacy PC hardware attached. 542 543 Say Y here to create a kernel to run on the SGI 320 or 540. 544 545 A kernel compiled for the Visual Workstation will run on general 546 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 547 548config STA2X11 549 bool "STA2X11 Companion Chip Support" 550 depends on X86_32_NON_STANDARD && PCI 551 select X86_DEV_DMA_OPS 552 select X86_DMA_REMAP 553 select SWIOTLB 554 select MFD_STA2X11 555 select ARCH_REQUIRE_GPIOLIB 556 default n 557 ---help--- 558 This adds support for boards based on the STA2X11 IO-Hub, 559 a.k.a. "ConneXt". The chip is used in place of the standard 560 PC chipset, so all "standard" peripherals are missing. If this 561 option is selected the kernel will still be able to boot on 562 standard PC machines. 563 564config X86_SUMMIT 565 bool "Summit/EXA (IBM x440)" 566 depends on X86_32_NON_STANDARD 567 ---help--- 568 This option is needed for IBM systems that use the Summit/EXA chipset. 569 In particular, it is needed for the x440. 570 571config X86_ES7000 572 bool "Unisys ES7000 IA32 series" 573 depends on X86_32_NON_STANDARD && X86_BIGSMP 574 ---help--- 575 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 576 supposed to run on an IA32-based Unisys ES7000 system. 577 578config X86_32_IRIS 579 tristate "Eurobraille/Iris poweroff module" 580 depends on X86_32 581 ---help--- 582 The Iris machines from EuroBraille do not have APM or ACPI support 583 to shut themselves down properly. A special I/O sequence is 584 needed to do so, which is what this module does at 585 kernel shutdown. 586 587 This is only for Iris machines from EuroBraille. 588 589 If unused, say N. 590 591config SCHED_OMIT_FRAME_POINTER 592 def_bool y 593 prompt "Single-depth WCHAN output" 594 depends on X86 595 ---help--- 596 Calculate simpler /proc/<PID>/wchan values. If this option 597 is disabled then wchan values will recurse back to the 598 caller function. This provides more accurate wchan values, 599 at the expense of slightly more scheduling overhead. 600 601 If in doubt, say "Y". 602 603menuconfig HYPERVISOR_GUEST 604 bool "Linux guest support" 605 ---help--- 606 Say Y here to enable options for running Linux under various hyper- 607 visors. This option enables basic hypervisor detection and platform 608 setup. 609 610 If you say N, all options in this submenu will be skipped and 611 disabled, and Linux guest support won't be built in. 612 613if HYPERVISOR_GUEST 614 615config PARAVIRT 616 bool "Enable paravirtualization code" 617 ---help--- 618 This changes the kernel so it can modify itself when it is run 619 under a hypervisor, potentially improving performance significantly 620 over full virtualization. However, when run without a hypervisor 621 the kernel is theoretically slower and slightly larger. 622 623config PARAVIRT_DEBUG 624 bool "paravirt-ops debugging" 625 depends on PARAVIRT && DEBUG_KERNEL 626 ---help--- 627 Enable to debug paravirt_ops internals. Specifically, BUG if 628 a paravirt_op is missing when it is called. 629 630config PARAVIRT_SPINLOCKS 631 bool "Paravirtualization layer for spinlocks" 632 depends on PARAVIRT && SMP 633 select UNINLINE_SPIN_UNLOCK 634 ---help--- 635 Paravirtualized spinlocks allow a pvops backend to replace the 636 spinlock implementation with something virtualization-friendly 637 (for example, block the virtual CPU rather than spinning). 638 639 It has a minimal impact on native kernels and gives a nice performance 640 benefit on paravirtualized KVM / Xen kernels. 641 642 If you are unsure how to answer this question, answer Y. 643 644source "arch/x86/xen/Kconfig" 645 646config KVM_GUEST 647 bool "KVM Guest support (including kvmclock)" 648 depends on PARAVIRT 649 select PARAVIRT_CLOCK 650 default y 651 ---help--- 652 This option enables various optimizations for running under the KVM 653 hypervisor. It includes a paravirtualized clock, so that instead 654 of relying on a PIT (or probably other) emulation by the 655 underlying device model, the host provides the guest with 656 timing infrastructure such as time of day, and system time 657 658config KVM_DEBUG_FS 659 bool "Enable debug information for KVM Guests in debugfs" 660 depends on KVM_GUEST && DEBUG_FS 661 default n 662 ---help--- 663 This option enables collection of various statistics for KVM guest. 664 Statistics are displayed in debugfs filesystem. Enabling this option 665 may incur significant overhead. 666 667source "arch/x86/lguest/Kconfig" 668 669config PARAVIRT_TIME_ACCOUNTING 670 bool "Paravirtual steal time accounting" 671 depends on PARAVIRT 672 default n 673 ---help--- 674 Select this option to enable fine granularity task steal time 675 accounting. Time spent executing other tasks in parallel with 676 the current vCPU is discounted from the vCPU power. To account for 677 that, there can be a small performance impact. 678 679 If in doubt, say N here. 680 681config PARAVIRT_CLOCK 682 bool 683 684endif #HYPERVISOR_GUEST 685 686config NO_BOOTMEM 687 def_bool y 688 689config MEMTEST 690 bool "Memtest" 691 ---help--- 692 This option adds a kernel parameter 'memtest', which allows memtest 693 to be set. 694 memtest=0, mean disabled; -- default 695 memtest=1, mean do 1 test pattern; 696 ... 697 memtest=4, mean do 4 test patterns. 698 If you are unsure how to answer this question, answer N. 699 700config X86_SUMMIT_NUMA 701 def_bool y 702 depends on X86_32 && NUMA && X86_32_NON_STANDARD 703 704config X86_CYCLONE_TIMER 705 def_bool y 706 depends on X86_SUMMIT 707 708source "arch/x86/Kconfig.cpu" 709 710config HPET_TIMER 711 def_bool X86_64 712 prompt "HPET Timer Support" if X86_32 713 ---help--- 714 Use the IA-PC HPET (High Precision Event Timer) to manage 715 time in preference to the PIT and RTC, if a HPET is 716 present. 717 HPET is the next generation timer replacing legacy 8254s. 718 The HPET provides a stable time base on SMP 719 systems, unlike the TSC, but it is more expensive to access, 720 as it is off-chip. You can find the HPET spec at 721 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 722 723 You can safely choose Y here. However, HPET will only be 724 activated if the platform and the BIOS support this feature. 725 Otherwise the 8254 will be used for timing services. 726 727 Choose N to continue using the legacy 8254 timer. 728 729config HPET_EMULATE_RTC 730 def_bool y 731 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 732 733config APB_TIMER 734 def_bool y if X86_INTEL_MID 735 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 736 select DW_APB_TIMER 737 depends on X86_INTEL_MID && SFI 738 help 739 APB timer is the replacement for 8254, HPET on X86 MID platforms. 740 The APBT provides a stable time base on SMP 741 systems, unlike the TSC, but it is more expensive to access, 742 as it is off-chip. APB timers are always running regardless of CPU 743 C states, they are used as per CPU clockevent device when possible. 744 745# Mark as expert because too many people got it wrong. 746# The code disables itself when not needed. 747config DMI 748 default y 749 bool "Enable DMI scanning" if EXPERT 750 ---help--- 751 Enabled scanning of DMI to identify machine quirks. Say Y 752 here unless you have verified that your setup is not 753 affected by entries in the DMI blacklist. Required by PNP 754 BIOS code. 755 756config GART_IOMMU 757 bool "Old AMD GART IOMMU support" 758 select SWIOTLB 759 depends on X86_64 && PCI && AMD_NB 760 ---help--- 761 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 762 GART based hardware IOMMUs. 763 764 The GART supports full DMA access for devices with 32-bit access 765 limitations, on systems with more than 3 GB. This is usually needed 766 for USB, sound, many IDE/SATA chipsets and some other devices. 767 768 Newer systems typically have a modern AMD IOMMU, supported via 769 the CONFIG_AMD_IOMMU=y config option. 770 771 In normal configurations this driver is only active when needed: 772 there's more than 3 GB of memory and the system contains a 773 32-bit limited device. 774 775 If unsure, say Y. 776 777config CALGARY_IOMMU 778 bool "IBM Calgary IOMMU support" 779 select SWIOTLB 780 depends on X86_64 && PCI 781 ---help--- 782 Support for hardware IOMMUs in IBM's xSeries x366 and x460 783 systems. Needed to run systems with more than 3GB of memory 784 properly with 32-bit PCI devices that do not support DAC 785 (Double Address Cycle). Calgary also supports bus level 786 isolation, where all DMAs pass through the IOMMU. This 787 prevents them from going anywhere except their intended 788 destination. This catches hard-to-find kernel bugs and 789 mis-behaving drivers and devices that do not use the DMA-API 790 properly to set up their DMA buffers. The IOMMU can be 791 turned off at boot time with the iommu=off parameter. 792 Normally the kernel will make the right choice by itself. 793 If unsure, say Y. 794 795config CALGARY_IOMMU_ENABLED_BY_DEFAULT 796 def_bool y 797 prompt "Should Calgary be enabled by default?" 798 depends on CALGARY_IOMMU 799 ---help--- 800 Should Calgary be enabled by default? if you choose 'y', Calgary 801 will be used (if it exists). If you choose 'n', Calgary will not be 802 used even if it exists. If you choose 'n' and would like to use 803 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 804 If unsure, say Y. 805 806# need this always selected by IOMMU for the VIA workaround 807config SWIOTLB 808 def_bool y if X86_64 809 ---help--- 810 Support for software bounce buffers used on x86-64 systems 811 which don't have a hardware IOMMU. Using this PCI devices 812 which can only access 32-bits of memory can be used on systems 813 with more than 3 GB of memory. 814 If unsure, say Y. 815 816config IOMMU_HELPER 817 def_bool y 818 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 819 820config MAXSMP 821 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 822 depends on X86_64 && SMP && DEBUG_KERNEL 823 select CPUMASK_OFFSTACK 824 ---help--- 825 Enable maximum number of CPUS and NUMA Nodes for this architecture. 826 If unsure, say N. 827 828config NR_CPUS 829 int "Maximum number of CPUs" if SMP && !MAXSMP 830 range 2 8 if SMP && X86_32 && !X86_BIGSMP 831 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 832 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 833 default "1" if !SMP 834 default "8192" if MAXSMP 835 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 836 default "8" if SMP 837 ---help--- 838 This allows you to specify the maximum number of CPUs which this 839 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 840 supported value is 4096, otherwise the maximum value is 512. The 841 minimum value which makes sense is 2. 842 843 This is purely to save memory - each supported CPU adds 844 approximately eight kilobytes to the kernel image. 845 846config SCHED_SMT 847 bool "SMT (Hyperthreading) scheduler support" 848 depends on X86_HT 849 ---help--- 850 SMT scheduler support improves the CPU scheduler's decision making 851 when dealing with Intel Pentium 4 chips with HyperThreading at a 852 cost of slightly increased overhead in some places. If unsure say 853 N here. 854 855config SCHED_MC 856 def_bool y 857 prompt "Multi-core scheduler support" 858 depends on X86_HT 859 ---help--- 860 Multi-core scheduler support improves the CPU scheduler's decision 861 making when dealing with multi-core CPU chips at a cost of slightly 862 increased overhead in some places. If unsure say N here. 863 864source "kernel/Kconfig.preempt" 865 866config X86_UP_APIC 867 bool "Local APIC support on uniprocessors" 868 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI 869 ---help--- 870 A local APIC (Advanced Programmable Interrupt Controller) is an 871 integrated interrupt controller in the CPU. If you have a single-CPU 872 system which has a processor with a local APIC, you can say Y here to 873 enable and use it. If you say Y here even though your machine doesn't 874 have a local APIC, then the kernel will still run with no slowdown at 875 all. The local APIC supports CPU-generated self-interrupts (timer, 876 performance counters), and the NMI watchdog which detects hard 877 lockups. 878 879config X86_UP_IOAPIC 880 bool "IO-APIC support on uniprocessors" 881 depends on X86_UP_APIC 882 ---help--- 883 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 884 SMP-capable replacement for PC-style interrupt controllers. Most 885 SMP systems and many recent uniprocessor systems have one. 886 887 If you have a single-CPU system with an IO-APIC, you can say Y here 888 to use it. If you say Y here even though your machine doesn't have 889 an IO-APIC, then the kernel will still run with no slowdown at all. 890 891config X86_LOCAL_APIC 892 def_bool y 893 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 894 895config X86_IO_APIC 896 def_bool y 897 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI 898 899config X86_VISWS_APIC 900 def_bool y 901 depends on X86_32 && X86_VISWS 902 903config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 904 bool "Reroute for broken boot IRQs" 905 depends on X86_IO_APIC 906 ---help--- 907 This option enables a workaround that fixes a source of 908 spurious interrupts. This is recommended when threaded 909 interrupt handling is used on systems where the generation of 910 superfluous "boot interrupts" cannot be disabled. 911 912 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 913 entry in the chipset's IO-APIC is masked (as, e.g. the RT 914 kernel does during interrupt handling). On chipsets where this 915 boot IRQ generation cannot be disabled, this workaround keeps 916 the original IRQ line masked so that only the equivalent "boot 917 IRQ" is delivered to the CPUs. The workaround also tells the 918 kernel to set up the IRQ handler on the boot IRQ line. In this 919 way only one interrupt is delivered to the kernel. Otherwise 920 the spurious second interrupt may cause the kernel to bring 921 down (vital) interrupt lines. 922 923 Only affects "broken" chipsets. Interrupt sharing may be 924 increased on these systems. 925 926config X86_MCE 927 bool "Machine Check / overheating reporting" 928 default y 929 ---help--- 930 Machine Check support allows the processor to notify the 931 kernel if it detects a problem (e.g. overheating, data corruption). 932 The action the kernel takes depends on the severity of the problem, 933 ranging from warning messages to halting the machine. 934 935config X86_MCE_INTEL 936 def_bool y 937 prompt "Intel MCE features" 938 depends on X86_MCE && X86_LOCAL_APIC 939 ---help--- 940 Additional support for intel specific MCE features such as 941 the thermal monitor. 942 943config X86_MCE_AMD 944 def_bool y 945 prompt "AMD MCE features" 946 depends on X86_MCE && X86_LOCAL_APIC 947 ---help--- 948 Additional support for AMD specific MCE features such as 949 the DRAM Error Threshold. 950 951config X86_ANCIENT_MCE 952 bool "Support for old Pentium 5 / WinChip machine checks" 953 depends on X86_32 && X86_MCE 954 ---help--- 955 Include support for machine check handling on old Pentium 5 or WinChip 956 systems. These typically need to be enabled explicitely on the command 957 line. 958 959config X86_MCE_THRESHOLD 960 depends on X86_MCE_AMD || X86_MCE_INTEL 961 def_bool y 962 963config X86_MCE_INJECT 964 depends on X86_MCE 965 tristate "Machine check injector support" 966 ---help--- 967 Provide support for injecting machine checks for testing purposes. 968 If you don't know what a machine check is and you don't do kernel 969 QA it is safe to say n. 970 971config X86_THERMAL_VECTOR 972 def_bool y 973 depends on X86_MCE_INTEL 974 975config VM86 976 bool "Enable VM86 support" if EXPERT 977 default y 978 depends on X86_32 979 ---help--- 980 This option is required by programs like DOSEMU to run 16-bit legacy 981 code on X86 processors. It also may be needed by software like 982 XFree86 to initialize some video cards via BIOS. Disabling this 983 option saves about 6k. 984 985config TOSHIBA 986 tristate "Toshiba Laptop support" 987 depends on X86_32 988 ---help--- 989 This adds a driver to safely access the System Management Mode of 990 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 991 not work on models with a Phoenix BIOS. The System Management Mode 992 is used to set the BIOS and power saving options on Toshiba portables. 993 994 For information on utilities to make use of this driver see the 995 Toshiba Linux utilities web site at: 996 <http://www.buzzard.org.uk/toshiba/>. 997 998 Say Y if you intend to run this kernel on a Toshiba portable. 999 Say N otherwise. 1000 1001config I8K 1002 tristate "Dell laptop support" 1003 select HWMON 1004 ---help--- 1005 This adds a driver to safely access the System Management Mode 1006 of the CPU on the Dell Inspiron 8000. The System Management Mode 1007 is used to read cpu temperature and cooling fan status and to 1008 control the fans on the I8K portables. 1009 1010 This driver has been tested only on the Inspiron 8000 but it may 1011 also work with other Dell laptops. You can force loading on other 1012 models by passing the parameter `force=1' to the module. Use at 1013 your own risk. 1014 1015 For information on utilities to make use of this driver see the 1016 I8K Linux utilities web site at: 1017 <http://people.debian.org/~dz/i8k/> 1018 1019 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 1020 Say N otherwise. 1021 1022config X86_REBOOTFIXUPS 1023 bool "Enable X86 board specific fixups for reboot" 1024 depends on X86_32 1025 ---help--- 1026 This enables chipset and/or board specific fixups to be done 1027 in order to get reboot to work correctly. This is only needed on 1028 some combinations of hardware and BIOS. The symptom, for which 1029 this config is intended, is when reboot ends with a stalled/hung 1030 system. 1031 1032 Currently, the only fixup is for the Geode machines using 1033 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1034 1035 Say Y if you want to enable the fixup. Currently, it's safe to 1036 enable this option even if you don't need it. 1037 Say N otherwise. 1038 1039config MICROCODE 1040 tristate "CPU microcode loading support" 1041 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1042 select FW_LOADER 1043 ---help--- 1044 1045 If you say Y here, you will be able to update the microcode on 1046 certain Intel and AMD processors. The Intel support is for the 1047 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1048 Xeon etc. The AMD support is for families 0x10 and later. You will 1049 obviously need the actual microcode binary data itself which is not 1050 shipped with the Linux kernel. 1051 1052 This option selects the general module only, you need to select 1053 at least one vendor specific module as well. 1054 1055 To compile this driver as a module, choose M here: the module 1056 will be called microcode. 1057 1058config MICROCODE_INTEL 1059 bool "Intel microcode loading support" 1060 depends on MICROCODE 1061 default MICROCODE 1062 select FW_LOADER 1063 ---help--- 1064 This options enables microcode patch loading support for Intel 1065 processors. 1066 1067 For latest news and information on obtaining all the required 1068 Intel ingredients for this driver, check: 1069 <http://www.urbanmyth.org/microcode/>. 1070 1071config MICROCODE_AMD 1072 bool "AMD microcode loading support" 1073 depends on MICROCODE 1074 select FW_LOADER 1075 ---help--- 1076 If you select this option, microcode patch loading support for AMD 1077 processors will be enabled. 1078 1079config MICROCODE_OLD_INTERFACE 1080 def_bool y 1081 depends on MICROCODE 1082 1083config MICROCODE_INTEL_LIB 1084 def_bool y 1085 depends on MICROCODE_INTEL 1086 1087config MICROCODE_INTEL_EARLY 1088 def_bool n 1089 1090config MICROCODE_AMD_EARLY 1091 def_bool n 1092 1093config MICROCODE_EARLY 1094 bool "Early load microcode" 1095 depends on MICROCODE=y && BLK_DEV_INITRD 1096 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1097 select MICROCODE_AMD_EARLY if MICROCODE_AMD 1098 default y 1099 help 1100 This option provides functionality to read additional microcode data 1101 at the beginning of initrd image. The data tells kernel to load 1102 microcode to CPU's as early as possible. No functional change if no 1103 microcode data is glued to the initrd, therefore it's safe to say Y. 1104 1105config X86_MSR 1106 tristate "/dev/cpu/*/msr - Model-specific register support" 1107 ---help--- 1108 This device gives privileged processes access to the x86 1109 Model-Specific Registers (MSRs). It is a character device with 1110 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1111 MSR accesses are directed to a specific CPU on multi-processor 1112 systems. 1113 1114config X86_CPUID 1115 tristate "/dev/cpu/*/cpuid - CPU information support" 1116 ---help--- 1117 This device gives processes access to the x86 CPUID instruction to 1118 be executed on a specific processor. It is a character device 1119 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1120 /dev/cpu/31/cpuid. 1121 1122choice 1123 prompt "High Memory Support" 1124 default HIGHMEM64G if X86_NUMAQ 1125 default HIGHMEM4G 1126 depends on X86_32 1127 1128config NOHIGHMEM 1129 bool "off" 1130 depends on !X86_NUMAQ 1131 ---help--- 1132 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1133 However, the address space of 32-bit x86 processors is only 4 1134 Gigabytes large. That means that, if you have a large amount of 1135 physical memory, not all of it can be "permanently mapped" by the 1136 kernel. The physical memory that's not permanently mapped is called 1137 "high memory". 1138 1139 If you are compiling a kernel which will never run on a machine with 1140 more than 1 Gigabyte total physical RAM, answer "off" here (default 1141 choice and suitable for most users). This will result in a "3GB/1GB" 1142 split: 3GB are mapped so that each process sees a 3GB virtual memory 1143 space and the remaining part of the 4GB virtual memory space is used 1144 by the kernel to permanently map as much physical memory as 1145 possible. 1146 1147 If the machine has between 1 and 4 Gigabytes physical RAM, then 1148 answer "4GB" here. 1149 1150 If more than 4 Gigabytes is used then answer "64GB" here. This 1151 selection turns Intel PAE (Physical Address Extension) mode on. 1152 PAE implements 3-level paging on IA32 processors. PAE is fully 1153 supported by Linux, PAE mode is implemented on all recent Intel 1154 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1155 then the kernel will not boot on CPUs that don't support PAE! 1156 1157 The actual amount of total physical memory will either be 1158 auto detected or can be forced by using a kernel command line option 1159 such as "mem=256M". (Try "man bootparam" or see the documentation of 1160 your boot loader (lilo or loadlin) about how to pass options to the 1161 kernel at boot time.) 1162 1163 If unsure, say "off". 1164 1165config HIGHMEM4G 1166 bool "4GB" 1167 depends on !X86_NUMAQ 1168 ---help--- 1169 Select this if you have a 32-bit processor and between 1 and 4 1170 gigabytes of physical RAM. 1171 1172config HIGHMEM64G 1173 bool "64GB" 1174 depends on !M486 1175 select X86_PAE 1176 ---help--- 1177 Select this if you have a 32-bit processor and more than 4 1178 gigabytes of physical RAM. 1179 1180endchoice 1181 1182choice 1183 prompt "Memory split" if EXPERT 1184 default VMSPLIT_3G 1185 depends on X86_32 1186 ---help--- 1187 Select the desired split between kernel and user memory. 1188 1189 If the address range available to the kernel is less than the 1190 physical memory installed, the remaining memory will be available 1191 as "high memory". Accessing high memory is a little more costly 1192 than low memory, as it needs to be mapped into the kernel first. 1193 Note that increasing the kernel address space limits the range 1194 available to user programs, making the address space there 1195 tighter. Selecting anything other than the default 3G/1G split 1196 will also likely make your kernel incompatible with binary-only 1197 kernel modules. 1198 1199 If you are not absolutely sure what you are doing, leave this 1200 option alone! 1201 1202 config VMSPLIT_3G 1203 bool "3G/1G user/kernel split" 1204 config VMSPLIT_3G_OPT 1205 depends on !X86_PAE 1206 bool "3G/1G user/kernel split (for full 1G low memory)" 1207 config VMSPLIT_2G 1208 bool "2G/2G user/kernel split" 1209 config VMSPLIT_2G_OPT 1210 depends on !X86_PAE 1211 bool "2G/2G user/kernel split (for full 2G low memory)" 1212 config VMSPLIT_1G 1213 bool "1G/3G user/kernel split" 1214endchoice 1215 1216config PAGE_OFFSET 1217 hex 1218 default 0xB0000000 if VMSPLIT_3G_OPT 1219 default 0x80000000 if VMSPLIT_2G 1220 default 0x78000000 if VMSPLIT_2G_OPT 1221 default 0x40000000 if VMSPLIT_1G 1222 default 0xC0000000 1223 depends on X86_32 1224 1225config HIGHMEM 1226 def_bool y 1227 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1228 1229config X86_PAE 1230 bool "PAE (Physical Address Extension) Support" 1231 depends on X86_32 && !HIGHMEM4G 1232 ---help--- 1233 PAE is required for NX support, and furthermore enables 1234 larger swapspace support for non-overcommit purposes. It 1235 has the cost of more pagetable lookup overhead, and also 1236 consumes more pagetable space per process. 1237 1238config ARCH_PHYS_ADDR_T_64BIT 1239 def_bool y 1240 depends on X86_64 || X86_PAE 1241 1242config ARCH_DMA_ADDR_T_64BIT 1243 def_bool y 1244 depends on X86_64 || HIGHMEM64G 1245 1246config DIRECT_GBPAGES 1247 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1248 default y 1249 depends on X86_64 1250 ---help--- 1251 Allow the kernel linear mapping to use 1GB pages on CPUs that 1252 support it. This can improve the kernel's performance a tiny bit by 1253 reducing TLB pressure. If in doubt, say "Y". 1254 1255# Common NUMA Features 1256config NUMA 1257 bool "Numa Memory Allocation and Scheduler Support" 1258 depends on SMP 1259 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI)) 1260 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1261 ---help--- 1262 Enable NUMA (Non Uniform Memory Access) support. 1263 1264 The kernel will try to allocate memory used by a CPU on the 1265 local memory controller of the CPU and add some more 1266 NUMA awareness to the kernel. 1267 1268 For 64-bit this is recommended if the system is Intel Core i7 1269 (or later), AMD Opteron, or EM64T NUMA. 1270 1271 For 32-bit this is only needed on (rare) 32-bit-only platforms 1272 that support NUMA topologies, such as NUMAQ / Summit, or if you 1273 boot a 32-bit kernel on a 64-bit NUMA platform. 1274 1275 Otherwise, you should say N. 1276 1277comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1278 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1279 1280config AMD_NUMA 1281 def_bool y 1282 prompt "Old style AMD Opteron NUMA detection" 1283 depends on X86_64 && NUMA && PCI 1284 ---help--- 1285 Enable AMD NUMA node topology detection. You should say Y here if 1286 you have a multi processor AMD system. This uses an old method to 1287 read the NUMA configuration directly from the builtin Northbridge 1288 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1289 which also takes priority if both are compiled in. 1290 1291config X86_64_ACPI_NUMA 1292 def_bool y 1293 prompt "ACPI NUMA detection" 1294 depends on X86_64 && NUMA && ACPI && PCI 1295 select ACPI_NUMA 1296 ---help--- 1297 Enable ACPI SRAT based node topology detection. 1298 1299# Some NUMA nodes have memory ranges that span 1300# other nodes. Even though a pfn is valid and 1301# between a node's start and end pfns, it may not 1302# reside on that node. See memmap_init_zone() 1303# for details. 1304config NODES_SPAN_OTHER_NODES 1305 def_bool y 1306 depends on X86_64_ACPI_NUMA 1307 1308config NUMA_EMU 1309 bool "NUMA emulation" 1310 depends on NUMA 1311 ---help--- 1312 Enable NUMA emulation. A flat machine will be split 1313 into virtual nodes when booted with "numa=fake=N", where N is the 1314 number of nodes. This is only useful for debugging. 1315 1316config NODES_SHIFT 1317 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1318 range 1 10 1319 default "10" if MAXSMP 1320 default "6" if X86_64 1321 default "4" if X86_NUMAQ 1322 default "3" 1323 depends on NEED_MULTIPLE_NODES 1324 ---help--- 1325 Specify the maximum number of NUMA Nodes available on the target 1326 system. Increases memory reserved to accommodate various tables. 1327 1328config ARCH_HAVE_MEMORY_PRESENT 1329 def_bool y 1330 depends on X86_32 && DISCONTIGMEM 1331 1332config NEED_NODE_MEMMAP_SIZE 1333 def_bool y 1334 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1335 1336config ARCH_FLATMEM_ENABLE 1337 def_bool y 1338 depends on X86_32 && !NUMA 1339 1340config ARCH_DISCONTIGMEM_ENABLE 1341 def_bool y 1342 depends on NUMA && X86_32 1343 1344config ARCH_DISCONTIGMEM_DEFAULT 1345 def_bool y 1346 depends on NUMA && X86_32 1347 1348config ARCH_SPARSEMEM_ENABLE 1349 def_bool y 1350 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1351 select SPARSEMEM_STATIC if X86_32 1352 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1353 1354config ARCH_SPARSEMEM_DEFAULT 1355 def_bool y 1356 depends on X86_64 1357 1358config ARCH_SELECT_MEMORY_MODEL 1359 def_bool y 1360 depends on ARCH_SPARSEMEM_ENABLE 1361 1362config ARCH_MEMORY_PROBE 1363 bool "Enable sysfs memory/probe interface" 1364 depends on X86_64 && MEMORY_HOTPLUG 1365 help 1366 This option enables a sysfs memory/probe interface for testing. 1367 See Documentation/memory-hotplug.txt for more information. 1368 If you are unsure how to answer this question, answer N. 1369 1370config ARCH_PROC_KCORE_TEXT 1371 def_bool y 1372 depends on X86_64 && PROC_KCORE 1373 1374config ILLEGAL_POINTER_VALUE 1375 hex 1376 default 0 if X86_32 1377 default 0xdead000000000000 if X86_64 1378 1379source "mm/Kconfig" 1380 1381config HIGHPTE 1382 bool "Allocate 3rd-level pagetables from highmem" 1383 depends on HIGHMEM 1384 ---help--- 1385 The VM uses one page table entry for each page of physical memory. 1386 For systems with a lot of RAM, this can be wasteful of precious 1387 low memory. Setting this option will put user-space page table 1388 entries in high memory. 1389 1390config X86_CHECK_BIOS_CORRUPTION 1391 bool "Check for low memory corruption" 1392 ---help--- 1393 Periodically check for memory corruption in low memory, which 1394 is suspected to be caused by BIOS. Even when enabled in the 1395 configuration, it is disabled at runtime. Enable it by 1396 setting "memory_corruption_check=1" on the kernel command 1397 line. By default it scans the low 64k of memory every 60 1398 seconds; see the memory_corruption_check_size and 1399 memory_corruption_check_period parameters in 1400 Documentation/kernel-parameters.txt to adjust this. 1401 1402 When enabled with the default parameters, this option has 1403 almost no overhead, as it reserves a relatively small amount 1404 of memory and scans it infrequently. It both detects corruption 1405 and prevents it from affecting the running system. 1406 1407 It is, however, intended as a diagnostic tool; if repeatable 1408 BIOS-originated corruption always affects the same memory, 1409 you can use memmap= to prevent the kernel from using that 1410 memory. 1411 1412config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1413 bool "Set the default setting of memory_corruption_check" 1414 depends on X86_CHECK_BIOS_CORRUPTION 1415 default y 1416 ---help--- 1417 Set whether the default state of memory_corruption_check is 1418 on or off. 1419 1420config X86_RESERVE_LOW 1421 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1422 default 64 1423 range 4 640 1424 ---help--- 1425 Specify the amount of low memory to reserve for the BIOS. 1426 1427 The first page contains BIOS data structures that the kernel 1428 must not use, so that page must always be reserved. 1429 1430 By default we reserve the first 64K of physical RAM, as a 1431 number of BIOSes are known to corrupt that memory range 1432 during events such as suspend/resume or monitor cable 1433 insertion, so it must not be used by the kernel. 1434 1435 You can set this to 4 if you are absolutely sure that you 1436 trust the BIOS to get all its memory reservations and usages 1437 right. If you know your BIOS have problems beyond the 1438 default 64K area, you can set this to 640 to avoid using the 1439 entire low memory range. 1440 1441 If you have doubts about the BIOS (e.g. suspend/resume does 1442 not work or there's kernel crashes after certain hardware 1443 hotplug events) then you might want to enable 1444 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1445 typical corruption patterns. 1446 1447 Leave this to the default value of 64 if you are unsure. 1448 1449config MATH_EMULATION 1450 bool 1451 prompt "Math emulation" if X86_32 1452 ---help--- 1453 Linux can emulate a math coprocessor (used for floating point 1454 operations) if you don't have one. 486DX and Pentium processors have 1455 a math coprocessor built in, 486SX and 386 do not, unless you added 1456 a 487DX or 387, respectively. (The messages during boot time can 1457 give you some hints here ["man dmesg"].) Everyone needs either a 1458 coprocessor or this emulation. 1459 1460 If you don't have a math coprocessor, you need to say Y here; if you 1461 say Y here even though you have a coprocessor, the coprocessor will 1462 be used nevertheless. (This behavior can be changed with the kernel 1463 command line option "no387", which comes handy if your coprocessor 1464 is broken. Try "man bootparam" or see the documentation of your boot 1465 loader (lilo or loadlin) about how to pass options to the kernel at 1466 boot time.) This means that it is a good idea to say Y here if you 1467 intend to use this kernel on different machines. 1468 1469 More information about the internals of the Linux math coprocessor 1470 emulation can be found in <file:arch/x86/math-emu/README>. 1471 1472 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1473 kernel, it won't hurt. 1474 1475config MTRR 1476 def_bool y 1477 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1478 ---help--- 1479 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1480 the Memory Type Range Registers (MTRRs) may be used to control 1481 processor access to memory ranges. This is most useful if you have 1482 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1483 allows bus write transfers to be combined into a larger transfer 1484 before bursting over the PCI/AGP bus. This can increase performance 1485 of image write operations 2.5 times or more. Saying Y here creates a 1486 /proc/mtrr file which may be used to manipulate your processor's 1487 MTRRs. Typically the X server should use this. 1488 1489 This code has a reasonably generic interface so that similar 1490 control registers on other processors can be easily supported 1491 as well: 1492 1493 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1494 Registers (ARRs) which provide a similar functionality to MTRRs. For 1495 these, the ARRs are used to emulate the MTRRs. 1496 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1497 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1498 write-combining. All of these processors are supported by this code 1499 and it makes sense to say Y here if you have one of them. 1500 1501 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1502 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1503 can lead to all sorts of problems, so it's good to say Y here. 1504 1505 You can safely say Y even if your machine doesn't have MTRRs, you'll 1506 just add about 9 KB to your kernel. 1507 1508 See <file:Documentation/x86/mtrr.txt> for more information. 1509 1510config MTRR_SANITIZER 1511 def_bool y 1512 prompt "MTRR cleanup support" 1513 depends on MTRR 1514 ---help--- 1515 Convert MTRR layout from continuous to discrete, so X drivers can 1516 add writeback entries. 1517 1518 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1519 The largest mtrr entry size for a continuous block can be set with 1520 mtrr_chunk_size. 1521 1522 If unsure, say Y. 1523 1524config MTRR_SANITIZER_ENABLE_DEFAULT 1525 int "MTRR cleanup enable value (0-1)" 1526 range 0 1 1527 default "0" 1528 depends on MTRR_SANITIZER 1529 ---help--- 1530 Enable mtrr cleanup default value 1531 1532config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1533 int "MTRR cleanup spare reg num (0-7)" 1534 range 0 7 1535 default "1" 1536 depends on MTRR_SANITIZER 1537 ---help--- 1538 mtrr cleanup spare entries default, it can be changed via 1539 mtrr_spare_reg_nr=N on the kernel command line. 1540 1541config X86_PAT 1542 def_bool y 1543 prompt "x86 PAT support" if EXPERT 1544 depends on MTRR 1545 ---help--- 1546 Use PAT attributes to setup page level cache control. 1547 1548 PATs are the modern equivalents of MTRRs and are much more 1549 flexible than MTRRs. 1550 1551 Say N here if you see bootup problems (boot crash, boot hang, 1552 spontaneous reboots) or a non-working video driver. 1553 1554 If unsure, say Y. 1555 1556config ARCH_USES_PG_UNCACHED 1557 def_bool y 1558 depends on X86_PAT 1559 1560config ARCH_RANDOM 1561 def_bool y 1562 prompt "x86 architectural random number generator" if EXPERT 1563 ---help--- 1564 Enable the x86 architectural RDRAND instruction 1565 (Intel Bull Mountain technology) to generate random numbers. 1566 If supported, this is a high bandwidth, cryptographically 1567 secure hardware random number generator. 1568 1569config X86_SMAP 1570 def_bool y 1571 prompt "Supervisor Mode Access Prevention" if EXPERT 1572 ---help--- 1573 Supervisor Mode Access Prevention (SMAP) is a security 1574 feature in newer Intel processors. There is a small 1575 performance cost if this enabled and turned on; there is 1576 also a small increase in the kernel size if this is enabled. 1577 1578 If unsure, say Y. 1579 1580config EFI 1581 bool "EFI runtime service support" 1582 depends on ACPI 1583 select UCS2_STRING 1584 ---help--- 1585 This enables the kernel to use EFI runtime services that are 1586 available (such as the EFI variable services). 1587 1588 This option is only useful on systems that have EFI firmware. 1589 In addition, you should use the latest ELILO loader available 1590 at <http://elilo.sourceforge.net> in order to take advantage 1591 of EFI runtime services. However, even with this option, the 1592 resultant kernel should continue to boot on existing non-EFI 1593 platforms. 1594 1595config EFI_STUB 1596 bool "EFI stub support" 1597 depends on EFI 1598 ---help--- 1599 This kernel feature allows a bzImage to be loaded directly 1600 by EFI firmware without the use of a bootloader. 1601 1602 See Documentation/efi-stub.txt for more information. 1603 1604config SECCOMP 1605 def_bool y 1606 prompt "Enable seccomp to safely compute untrusted bytecode" 1607 ---help--- 1608 This kernel feature is useful for number crunching applications 1609 that may need to compute untrusted bytecode during their 1610 execution. By using pipes or other transports made available to 1611 the process as file descriptors supporting the read/write 1612 syscalls, it's possible to isolate those applications in 1613 their own address space using seccomp. Once seccomp is 1614 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1615 and the task is only allowed to execute a few safe syscalls 1616 defined by each seccomp mode. 1617 1618 If unsure, say Y. Only embedded should say N here. 1619 1620config CC_STACKPROTECTOR 1621 bool "Enable -fstack-protector buffer overflow detection" 1622 ---help--- 1623 This option turns on the -fstack-protector GCC feature. This 1624 feature puts, at the beginning of functions, a canary value on 1625 the stack just before the return address, and validates 1626 the value just before actually returning. Stack based buffer 1627 overflows (that need to overwrite this return address) now also 1628 overwrite the canary, which gets detected and the attack is then 1629 neutralized via a kernel panic. 1630 1631 This feature requires gcc version 4.2 or above, or a distribution 1632 gcc with the feature backported. Older versions are automatically 1633 detected and for those versions, this configuration option is 1634 ignored. (and a warning is printed during bootup) 1635 1636source kernel/Kconfig.hz 1637 1638config KEXEC 1639 bool "kexec system call" 1640 ---help--- 1641 kexec is a system call that implements the ability to shutdown your 1642 current kernel, and to start another kernel. It is like a reboot 1643 but it is independent of the system firmware. And like a reboot 1644 you can start any kernel with it, not just Linux. 1645 1646 The name comes from the similarity to the exec system call. 1647 1648 It is an ongoing process to be certain the hardware in a machine 1649 is properly shutdown, so do not be surprised if this code does not 1650 initially work for you. As of this writing the exact hardware 1651 interface is strongly in flux, so no good recommendation can be 1652 made. 1653 1654config CRASH_DUMP 1655 bool "kernel crash dumps" 1656 depends on X86_64 || (X86_32 && HIGHMEM) 1657 ---help--- 1658 Generate crash dump after being started by kexec. 1659 This should be normally only set in special crash dump kernels 1660 which are loaded in the main kernel with kexec-tools into 1661 a specially reserved region and then later executed after 1662 a crash by kdump/kexec. The crash dump kernel must be compiled 1663 to a memory address not used by the main kernel or BIOS using 1664 PHYSICAL_START, or it must be built as a relocatable image 1665 (CONFIG_RELOCATABLE=y). 1666 For more details see Documentation/kdump/kdump.txt 1667 1668config KEXEC_JUMP 1669 bool "kexec jump" 1670 depends on KEXEC && HIBERNATION 1671 ---help--- 1672 Jump between original kernel and kexeced kernel and invoke 1673 code in physical address mode via KEXEC 1674 1675config PHYSICAL_START 1676 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1677 default "0x1000000" 1678 ---help--- 1679 This gives the physical address where the kernel is loaded. 1680 1681 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1682 bzImage will decompress itself to above physical address and 1683 run from there. Otherwise, bzImage will run from the address where 1684 it has been loaded by the boot loader and will ignore above physical 1685 address. 1686 1687 In normal kdump cases one does not have to set/change this option 1688 as now bzImage can be compiled as a completely relocatable image 1689 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1690 address. This option is mainly useful for the folks who don't want 1691 to use a bzImage for capturing the crash dump and want to use a 1692 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1693 to be specifically compiled to run from a specific memory area 1694 (normally a reserved region) and this option comes handy. 1695 1696 So if you are using bzImage for capturing the crash dump, 1697 leave the value here unchanged to 0x1000000 and set 1698 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1699 for capturing the crash dump change this value to start of 1700 the reserved region. In other words, it can be set based on 1701 the "X" value as specified in the "crashkernel=YM@XM" 1702 command line boot parameter passed to the panic-ed 1703 kernel. Please take a look at Documentation/kdump/kdump.txt 1704 for more details about crash dumps. 1705 1706 Usage of bzImage for capturing the crash dump is recommended as 1707 one does not have to build two kernels. Same kernel can be used 1708 as production kernel and capture kernel. Above option should have 1709 gone away after relocatable bzImage support is introduced. But it 1710 is present because there are users out there who continue to use 1711 vmlinux for dump capture. This option should go away down the 1712 line. 1713 1714 Don't change this unless you know what you are doing. 1715 1716config RELOCATABLE 1717 bool "Build a relocatable kernel" 1718 default y 1719 ---help--- 1720 This builds a kernel image that retains relocation information 1721 so it can be loaded someplace besides the default 1MB. 1722 The relocations tend to make the kernel binary about 10% larger, 1723 but are discarded at runtime. 1724 1725 One use is for the kexec on panic case where the recovery kernel 1726 must live at a different physical address than the primary 1727 kernel. 1728 1729 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1730 it has been loaded at and the compile time physical address 1731 (CONFIG_PHYSICAL_START) is ignored. 1732 1733# Relocation on x86-32 needs some additional build support 1734config X86_NEED_RELOCS 1735 def_bool y 1736 depends on X86_32 && RELOCATABLE 1737 1738config PHYSICAL_ALIGN 1739 hex "Alignment value to which kernel should be aligned" 1740 default "0x1000000" 1741 range 0x2000 0x1000000 if X86_32 1742 range 0x200000 0x1000000 if X86_64 1743 ---help--- 1744 This value puts the alignment restrictions on physical address 1745 where kernel is loaded and run from. Kernel is compiled for an 1746 address which meets above alignment restriction. 1747 1748 If bootloader loads the kernel at a non-aligned address and 1749 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1750 address aligned to above value and run from there. 1751 1752 If bootloader loads the kernel at a non-aligned address and 1753 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1754 load address and decompress itself to the address it has been 1755 compiled for and run from there. The address for which kernel is 1756 compiled already meets above alignment restrictions. Hence the 1757 end result is that kernel runs from a physical address meeting 1758 above alignment restrictions. 1759 1760 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1761 this value must be a multiple of 0x200000. 1762 1763 Don't change this unless you know what you are doing. 1764 1765config HOTPLUG_CPU 1766 bool "Support for hot-pluggable CPUs" 1767 depends on SMP 1768 ---help--- 1769 Say Y here to allow turning CPUs off and on. CPUs can be 1770 controlled through /sys/devices/system/cpu. 1771 ( Note: power management support will enable this option 1772 automatically on SMP systems. ) 1773 Say N if you want to disable CPU hotplug. 1774 1775config BOOTPARAM_HOTPLUG_CPU0 1776 bool "Set default setting of cpu0_hotpluggable" 1777 default n 1778 depends on HOTPLUG_CPU 1779 ---help--- 1780 Set whether default state of cpu0_hotpluggable is on or off. 1781 1782 Say Y here to enable CPU0 hotplug by default. If this switch 1783 is turned on, there is no need to give cpu0_hotplug kernel 1784 parameter and the CPU0 hotplug feature is enabled by default. 1785 1786 Please note: there are two known CPU0 dependencies if you want 1787 to enable the CPU0 hotplug feature either by this switch or by 1788 cpu0_hotplug kernel parameter. 1789 1790 First, resume from hibernate or suspend always starts from CPU0. 1791 So hibernate and suspend are prevented if CPU0 is offline. 1792 1793 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1794 offline if any interrupt can not migrate out of CPU0. There may 1795 be other CPU0 dependencies. 1796 1797 Please make sure the dependencies are under your control before 1798 you enable this feature. 1799 1800 Say N if you don't want to enable CPU0 hotplug feature by default. 1801 You still can enable the CPU0 hotplug feature at boot by kernel 1802 parameter cpu0_hotplug. 1803 1804config DEBUG_HOTPLUG_CPU0 1805 def_bool n 1806 prompt "Debug CPU0 hotplug" 1807 depends on HOTPLUG_CPU 1808 ---help--- 1809 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 1810 soon as possible and boots up userspace with CPU0 offlined. User 1811 can online CPU0 back after boot time. 1812 1813 To debug CPU0 hotplug, you need to enable CPU0 offline/online 1814 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 1815 compilation or giving cpu0_hotplug kernel parameter at boot. 1816 1817 If unsure, say N. 1818 1819config COMPAT_VDSO 1820 def_bool y 1821 prompt "Compat VDSO support" 1822 depends on X86_32 || IA32_EMULATION 1823 ---help--- 1824 Map the 32-bit VDSO to the predictable old-style address too. 1825 1826 Say N here if you are running a sufficiently recent glibc 1827 version (2.3.3 or later), to remove the high-mapped 1828 VDSO mapping and to exclusively use the randomized VDSO. 1829 1830 If unsure, say Y. 1831 1832config CMDLINE_BOOL 1833 bool "Built-in kernel command line" 1834 ---help--- 1835 Allow for specifying boot arguments to the kernel at 1836 build time. On some systems (e.g. embedded ones), it is 1837 necessary or convenient to provide some or all of the 1838 kernel boot arguments with the kernel itself (that is, 1839 to not rely on the boot loader to provide them.) 1840 1841 To compile command line arguments into the kernel, 1842 set this option to 'Y', then fill in the 1843 the boot arguments in CONFIG_CMDLINE. 1844 1845 Systems with fully functional boot loaders (i.e. non-embedded) 1846 should leave this option set to 'N'. 1847 1848config CMDLINE 1849 string "Built-in kernel command string" 1850 depends on CMDLINE_BOOL 1851 default "" 1852 ---help--- 1853 Enter arguments here that should be compiled into the kernel 1854 image and used at boot time. If the boot loader provides a 1855 command line at boot time, it is appended to this string to 1856 form the full kernel command line, when the system boots. 1857 1858 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1859 change this behavior. 1860 1861 In most cases, the command line (whether built-in or provided 1862 by the boot loader) should specify the device for the root 1863 file system. 1864 1865config CMDLINE_OVERRIDE 1866 bool "Built-in command line overrides boot loader arguments" 1867 depends on CMDLINE_BOOL 1868 ---help--- 1869 Set this option to 'Y' to have the kernel ignore the boot loader 1870 command line, and use ONLY the built-in command line. 1871 1872 This is used to work around broken boot loaders. This should 1873 be set to 'N' under normal conditions. 1874 1875endmenu 1876 1877config ARCH_ENABLE_MEMORY_HOTPLUG 1878 def_bool y 1879 depends on X86_64 || (X86_32 && HIGHMEM) 1880 1881config ARCH_ENABLE_MEMORY_HOTREMOVE 1882 def_bool y 1883 depends on MEMORY_HOTPLUG 1884 1885config USE_PERCPU_NUMA_NODE_ID 1886 def_bool y 1887 depends on NUMA 1888 1889config ARCH_ENABLE_SPLIT_PMD_PTLOCK 1890 def_bool y 1891 depends on X86_64 || X86_PAE 1892 1893menu "Power management and ACPI options" 1894 1895config ARCH_HIBERNATION_HEADER 1896 def_bool y 1897 depends on X86_64 && HIBERNATION 1898 1899source "kernel/power/Kconfig" 1900 1901source "drivers/acpi/Kconfig" 1902 1903source "drivers/sfi/Kconfig" 1904 1905config X86_APM_BOOT 1906 def_bool y 1907 depends on APM 1908 1909menuconfig APM 1910 tristate "APM (Advanced Power Management) BIOS support" 1911 depends on X86_32 && PM_SLEEP 1912 ---help--- 1913 APM is a BIOS specification for saving power using several different 1914 techniques. This is mostly useful for battery powered laptops with 1915 APM compliant BIOSes. If you say Y here, the system time will be 1916 reset after a RESUME operation, the /proc/apm device will provide 1917 battery status information, and user-space programs will receive 1918 notification of APM "events" (e.g. battery status change). 1919 1920 If you select "Y" here, you can disable actual use of the APM 1921 BIOS by passing the "apm=off" option to the kernel at boot time. 1922 1923 Note that the APM support is almost completely disabled for 1924 machines with more than one CPU. 1925 1926 In order to use APM, you will need supporting software. For location 1927 and more information, read <file:Documentation/power/apm-acpi.txt> 1928 and the Battery Powered Linux mini-HOWTO, available from 1929 <http://www.tldp.org/docs.html#howto>. 1930 1931 This driver does not spin down disk drives (see the hdparm(8) 1932 manpage ("man 8 hdparm") for that), and it doesn't turn off 1933 VESA-compliant "green" monitors. 1934 1935 This driver does not support the TI 4000M TravelMate and the ACER 1936 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1937 desktop machines also don't have compliant BIOSes, and this driver 1938 may cause those machines to panic during the boot phase. 1939 1940 Generally, if you don't have a battery in your machine, there isn't 1941 much point in using this driver and you should say N. If you get 1942 random kernel OOPSes or reboots that don't seem to be related to 1943 anything, try disabling/enabling this option (or disabling/enabling 1944 APM in your BIOS). 1945 1946 Some other things you should try when experiencing seemingly random, 1947 "weird" problems: 1948 1949 1) make sure that you have enough swap space and that it is 1950 enabled. 1951 2) pass the "no-hlt" option to the kernel 1952 3) switch on floating point emulation in the kernel and pass 1953 the "no387" option to the kernel 1954 4) pass the "floppy=nodma" option to the kernel 1955 5) pass the "mem=4M" option to the kernel (thereby disabling 1956 all but the first 4 MB of RAM) 1957 6) make sure that the CPU is not over clocked. 1958 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1959 8) disable the cache from your BIOS settings 1960 9) install a fan for the video card or exchange video RAM 1961 10) install a better fan for the CPU 1962 11) exchange RAM chips 1963 12) exchange the motherboard. 1964 1965 To compile this driver as a module, choose M here: the 1966 module will be called apm. 1967 1968if APM 1969 1970config APM_IGNORE_USER_SUSPEND 1971 bool "Ignore USER SUSPEND" 1972 ---help--- 1973 This option will ignore USER SUSPEND requests. On machines with a 1974 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1975 series notebooks, it is necessary to say Y because of a BIOS bug. 1976 1977config APM_DO_ENABLE 1978 bool "Enable PM at boot time" 1979 ---help--- 1980 Enable APM features at boot time. From page 36 of the APM BIOS 1981 specification: "When disabled, the APM BIOS does not automatically 1982 power manage devices, enter the Standby State, enter the Suspend 1983 State, or take power saving steps in response to CPU Idle calls." 1984 This driver will make CPU Idle calls when Linux is idle (unless this 1985 feature is turned off -- see "Do CPU IDLE calls", below). This 1986 should always save battery power, but more complicated APM features 1987 will be dependent on your BIOS implementation. You may need to turn 1988 this option off if your computer hangs at boot time when using APM 1989 support, or if it beeps continuously instead of suspending. Turn 1990 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1991 T400CDT. This is off by default since most machines do fine without 1992 this feature. 1993 1994config APM_CPU_IDLE 1995 depends on CPU_IDLE 1996 bool "Make CPU Idle calls when idle" 1997 ---help--- 1998 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1999 On some machines, this can activate improved power savings, such as 2000 a slowed CPU clock rate, when the machine is idle. These idle calls 2001 are made after the idle loop has run for some length of time (e.g., 2002 333 mS). On some machines, this will cause a hang at boot time or 2003 whenever the CPU becomes idle. (On machines with more than one CPU, 2004 this option does nothing.) 2005 2006config APM_DISPLAY_BLANK 2007 bool "Enable console blanking using APM" 2008 ---help--- 2009 Enable console blanking using the APM. Some laptops can use this to 2010 turn off the LCD backlight when the screen blanker of the Linux 2011 virtual console blanks the screen. Note that this is only used by 2012 the virtual console screen blanker, and won't turn off the backlight 2013 when using the X Window system. This also doesn't have anything to 2014 do with your VESA-compliant power-saving monitor. Further, this 2015 option doesn't work for all laptops -- it might not turn off your 2016 backlight at all, or it might print a lot of errors to the console, 2017 especially if you are using gpm. 2018 2019config APM_ALLOW_INTS 2020 bool "Allow interrupts during APM BIOS calls" 2021 ---help--- 2022 Normally we disable external interrupts while we are making calls to 2023 the APM BIOS as a measure to lessen the effects of a badly behaving 2024 BIOS implementation. The BIOS should reenable interrupts if it 2025 needs to. Unfortunately, some BIOSes do not -- especially those in 2026 many of the newer IBM Thinkpads. If you experience hangs when you 2027 suspend, try setting this to Y. Otherwise, say N. 2028 2029endif # APM 2030 2031source "drivers/cpufreq/Kconfig" 2032 2033source "drivers/cpuidle/Kconfig" 2034 2035source "drivers/idle/Kconfig" 2036 2037endmenu 2038 2039 2040menu "Bus options (PCI etc.)" 2041 2042config PCI 2043 bool "PCI support" 2044 default y 2045 ---help--- 2046 Find out whether you have a PCI motherboard. PCI is the name of a 2047 bus system, i.e. the way the CPU talks to the other stuff inside 2048 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2049 VESA. If you have PCI, say Y, otherwise N. 2050 2051choice 2052 prompt "PCI access mode" 2053 depends on X86_32 && PCI 2054 default PCI_GOANY 2055 ---help--- 2056 On PCI systems, the BIOS can be used to detect the PCI devices and 2057 determine their configuration. However, some old PCI motherboards 2058 have BIOS bugs and may crash if this is done. Also, some embedded 2059 PCI-based systems don't have any BIOS at all. Linux can also try to 2060 detect the PCI hardware directly without using the BIOS. 2061 2062 With this option, you can specify how Linux should detect the 2063 PCI devices. If you choose "BIOS", the BIOS will be used, 2064 if you choose "Direct", the BIOS won't be used, and if you 2065 choose "MMConfig", then PCI Express MMCONFIG will be used. 2066 If you choose "Any", the kernel will try MMCONFIG, then the 2067 direct access method and falls back to the BIOS if that doesn't 2068 work. If unsure, go with the default, which is "Any". 2069 2070config PCI_GOBIOS 2071 bool "BIOS" 2072 2073config PCI_GOMMCONFIG 2074 bool "MMConfig" 2075 2076config PCI_GODIRECT 2077 bool "Direct" 2078 2079config PCI_GOOLPC 2080 bool "OLPC XO-1" 2081 depends on OLPC 2082 2083config PCI_GOANY 2084 bool "Any" 2085 2086endchoice 2087 2088config PCI_BIOS 2089 def_bool y 2090 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2091 2092# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2093config PCI_DIRECT 2094 def_bool y 2095 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2096 2097config PCI_MMCONFIG 2098 def_bool y 2099 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2100 2101config PCI_OLPC 2102 def_bool y 2103 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2104 2105config PCI_XEN 2106 def_bool y 2107 depends on PCI && XEN 2108 select SWIOTLB_XEN 2109 2110config PCI_DOMAINS 2111 def_bool y 2112 depends on PCI 2113 2114config PCI_MMCONFIG 2115 bool "Support mmconfig PCI config space access" 2116 depends on X86_64 && PCI && ACPI 2117 2118config PCI_CNB20LE_QUIRK 2119 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2120 depends on PCI 2121 help 2122 Read the PCI windows out of the CNB20LE host bridge. This allows 2123 PCI hotplug to work on systems with the CNB20LE chipset which do 2124 not have ACPI. 2125 2126 There's no public spec for this chipset, and this functionality 2127 is known to be incomplete. 2128 2129 You should say N unless you know you need this. 2130 2131source "drivers/pci/pcie/Kconfig" 2132 2133source "drivers/pci/Kconfig" 2134 2135# x86_64 have no ISA slots, but can have ISA-style DMA. 2136config ISA_DMA_API 2137 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2138 default y 2139 help 2140 Enables ISA-style DMA support for devices requiring such controllers. 2141 If unsure, say Y. 2142 2143if X86_32 2144 2145config ISA 2146 bool "ISA support" 2147 ---help--- 2148 Find out whether you have ISA slots on your motherboard. ISA is the 2149 name of a bus system, i.e. the way the CPU talks to the other stuff 2150 inside your box. Other bus systems are PCI, EISA, MicroChannel 2151 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2152 newer boards don't support it. If you have ISA, say Y, otherwise N. 2153 2154config EISA 2155 bool "EISA support" 2156 depends on ISA 2157 ---help--- 2158 The Extended Industry Standard Architecture (EISA) bus was 2159 developed as an open alternative to the IBM MicroChannel bus. 2160 2161 The EISA bus provided some of the features of the IBM MicroChannel 2162 bus while maintaining backward compatibility with cards made for 2163 the older ISA bus. The EISA bus saw limited use between 1988 and 2164 1995 when it was made obsolete by the PCI bus. 2165 2166 Say Y here if you are building a kernel for an EISA-based machine. 2167 2168 Otherwise, say N. 2169 2170source "drivers/eisa/Kconfig" 2171 2172config SCx200 2173 tristate "NatSemi SCx200 support" 2174 ---help--- 2175 This provides basic support for National Semiconductor's 2176 (now AMD's) Geode processors. The driver probes for the 2177 PCI-IDs of several on-chip devices, so its a good dependency 2178 for other scx200_* drivers. 2179 2180 If compiled as a module, the driver is named scx200. 2181 2182config SCx200HR_TIMER 2183 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2184 depends on SCx200 2185 default y 2186 ---help--- 2187 This driver provides a clocksource built upon the on-chip 2188 27MHz high-resolution timer. Its also a workaround for 2189 NSC Geode SC-1100's buggy TSC, which loses time when the 2190 processor goes idle (as is done by the scheduler). The 2191 other workaround is idle=poll boot option. 2192 2193config OLPC 2194 bool "One Laptop Per Child support" 2195 depends on !X86_PAE 2196 select GPIOLIB 2197 select OF 2198 select OF_PROMTREE 2199 select IRQ_DOMAIN 2200 ---help--- 2201 Add support for detecting the unique features of the OLPC 2202 XO hardware. 2203 2204config OLPC_XO1_PM 2205 bool "OLPC XO-1 Power Management" 2206 depends on OLPC && MFD_CS5535 && PM_SLEEP 2207 select MFD_CORE 2208 ---help--- 2209 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2210 2211config OLPC_XO1_RTC 2212 bool "OLPC XO-1 Real Time Clock" 2213 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2214 ---help--- 2215 Add support for the XO-1 real time clock, which can be used as a 2216 programmable wakeup source. 2217 2218config OLPC_XO1_SCI 2219 bool "OLPC XO-1 SCI extras" 2220 depends on OLPC && OLPC_XO1_PM 2221 depends on INPUT=y 2222 select POWER_SUPPLY 2223 select GPIO_CS5535 2224 select MFD_CORE 2225 ---help--- 2226 Add support for SCI-based features of the OLPC XO-1 laptop: 2227 - EC-driven system wakeups 2228 - Power button 2229 - Ebook switch 2230 - Lid switch 2231 - AC adapter status updates 2232 - Battery status updates 2233 2234config OLPC_XO15_SCI 2235 bool "OLPC XO-1.5 SCI extras" 2236 depends on OLPC && ACPI 2237 select POWER_SUPPLY 2238 ---help--- 2239 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2240 - EC-driven system wakeups 2241 - AC adapter status updates 2242 - Battery status updates 2243 2244config ALIX 2245 bool "PCEngines ALIX System Support (LED setup)" 2246 select GPIOLIB 2247 ---help--- 2248 This option enables system support for the PCEngines ALIX. 2249 At present this just sets up LEDs for GPIO control on 2250 ALIX2/3/6 boards. However, other system specific setup should 2251 get added here. 2252 2253 Note: You must still enable the drivers for GPIO and LED support 2254 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2255 2256 Note: You have to set alix.force=1 for boards with Award BIOS. 2257 2258config NET5501 2259 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2260 select GPIOLIB 2261 ---help--- 2262 This option enables system support for the Soekris Engineering net5501. 2263 2264config GEOS 2265 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2266 select GPIOLIB 2267 depends on DMI 2268 ---help--- 2269 This option enables system support for the Traverse Technologies GEOS. 2270 2271config TS5500 2272 bool "Technologic Systems TS-5500 platform support" 2273 depends on MELAN 2274 select CHECK_SIGNATURE 2275 select NEW_LEDS 2276 select LEDS_CLASS 2277 ---help--- 2278 This option enables system support for the Technologic Systems TS-5500. 2279 2280endif # X86_32 2281 2282config AMD_NB 2283 def_bool y 2284 depends on CPU_SUP_AMD && PCI 2285 2286source "drivers/pcmcia/Kconfig" 2287 2288source "drivers/pci/hotplug/Kconfig" 2289 2290config RAPIDIO 2291 tristate "RapidIO support" 2292 depends on PCI 2293 default n 2294 help 2295 If enabled this option will include drivers and the core 2296 infrastructure code to support RapidIO interconnect devices. 2297 2298source "drivers/rapidio/Kconfig" 2299 2300config X86_SYSFB 2301 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2302 help 2303 Firmwares often provide initial graphics framebuffers so the BIOS, 2304 bootloader or kernel can show basic video-output during boot for 2305 user-guidance and debugging. Historically, x86 used the VESA BIOS 2306 Extensions and EFI-framebuffers for this, which are mostly limited 2307 to x86. 2308 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2309 framebuffers so the new generic system-framebuffer drivers can be 2310 used on x86. If the framebuffer is not compatible with the generic 2311 modes, it is adverticed as fallback platform framebuffer so legacy 2312 drivers like efifb, vesafb and uvesafb can pick it up. 2313 If this option is not selected, all system framebuffers are always 2314 marked as fallback platform framebuffers as usual. 2315 2316 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2317 not be able to pick up generic system framebuffers if this option 2318 is selected. You are highly encouraged to enable simplefb as 2319 replacement if you select this option. simplefb can correctly deal 2320 with generic system framebuffers. But you should still keep vesafb 2321 and others enabled as fallback if a system framebuffer is 2322 incompatible with simplefb. 2323 2324 If unsure, say Y. 2325 2326endmenu 2327 2328 2329menu "Executable file formats / Emulations" 2330 2331source "fs/Kconfig.binfmt" 2332 2333config IA32_EMULATION 2334 bool "IA32 Emulation" 2335 depends on X86_64 2336 select BINFMT_ELF 2337 select COMPAT_BINFMT_ELF 2338 select HAVE_UID16 2339 ---help--- 2340 Include code to run legacy 32-bit programs under a 2341 64-bit kernel. You should likely turn this on, unless you're 2342 100% sure that you don't have any 32-bit programs left. 2343 2344config IA32_AOUT 2345 tristate "IA32 a.out support" 2346 depends on IA32_EMULATION 2347 ---help--- 2348 Support old a.out binaries in the 32bit emulation. 2349 2350config X86_X32 2351 bool "x32 ABI for 64-bit mode" 2352 depends on X86_64 && IA32_EMULATION 2353 ---help--- 2354 Include code to run binaries for the x32 native 32-bit ABI 2355 for 64-bit processors. An x32 process gets access to the 2356 full 64-bit register file and wide data path while leaving 2357 pointers at 32 bits for smaller memory footprint. 2358 2359 You will need a recent binutils (2.22 or later) with 2360 elf32_x86_64 support enabled to compile a kernel with this 2361 option set. 2362 2363config COMPAT 2364 def_bool y 2365 depends on IA32_EMULATION || X86_X32 2366 select ARCH_WANT_OLD_COMPAT_IPC 2367 2368if COMPAT 2369config COMPAT_FOR_U64_ALIGNMENT 2370 def_bool y 2371 2372config SYSVIPC_COMPAT 2373 def_bool y 2374 depends on SYSVIPC 2375 2376config KEYS_COMPAT 2377 def_bool y 2378 depends on KEYS 2379endif 2380 2381endmenu 2382 2383 2384config HAVE_ATOMIC_IOMAP 2385 def_bool y 2386 depends on X86_32 2387 2388config X86_DEV_DMA_OPS 2389 bool 2390 depends on X86_64 || STA2X11 2391 2392config X86_DMA_REMAP 2393 bool 2394 depends on STA2X11 2395 2396source "net/Kconfig" 2397 2398source "drivers/Kconfig" 2399 2400source "drivers/firmware/Kconfig" 2401 2402source "fs/Kconfig" 2403 2404source "arch/x86/Kconfig.debug" 2405 2406source "security/Kconfig" 2407 2408source "crypto/Kconfig" 2409 2410source "arch/x86/kvm/Kconfig" 2411 2412source "lib/Kconfig" 2413