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 13config X86_64 14 def_bool y 15 depends on 64BIT 16 17### Arch settings 18config X86 19 def_bool y 20 select ACPI_LEGACY_TABLES_LOOKUP if ACPI 21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 22 select ANON_INODES 23 select ARCH_CLOCKSOURCE_DATA 24 select ARCH_DISCARD_MEMBLOCK 25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 27 select ARCH_HAS_DEVMEM_IS_ALLOWED 28 select ARCH_HAS_ELF_RANDOMIZE 29 select ARCH_HAS_FAST_MULTIPLIER 30 select ARCH_HAS_GCOV_PROFILE_ALL 31 select ARCH_HAS_KCOV if X86_64 32 select ARCH_HAS_PMEM_API if X86_64 33 select ARCH_HAS_MMIO_FLUSH 34 select ARCH_HAS_SG_CHAIN 35 select ARCH_HAS_UBSAN_SANITIZE_ALL 36 select ARCH_HAVE_NMI_SAFE_CMPXCHG 37 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 38 select ARCH_MIGHT_HAVE_PC_PARPORT 39 select ARCH_MIGHT_HAVE_PC_SERIO 40 select ARCH_SUPPORTS_ATOMIC_RMW 41 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 42 select ARCH_SUPPORTS_INT128 if X86_64 43 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 44 select ARCH_USE_BUILTIN_BSWAP 45 select ARCH_USE_CMPXCHG_LOCKREF if X86_64 46 select ARCH_USE_QUEUED_RWLOCKS 47 select ARCH_USE_QUEUED_SPINLOCKS 48 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 49 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 50 select ARCH_WANT_FRAME_POINTERS 51 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 52 select ARCH_WANT_OPTIONAL_GPIOLIB 53 select BUILDTIME_EXTABLE_SORT 54 select CLKEVT_I8253 55 select CLKSRC_I8253 if X86_32 56 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 57 select CLOCKSOURCE_WATCHDOG 58 select CLONE_BACKWARDS if X86_32 59 select COMPAT_OLD_SIGACTION if IA32_EMULATION 60 select DCACHE_WORD_ACCESS 61 select EDAC_ATOMIC_SCRUB 62 select EDAC_SUPPORT 63 select GENERIC_CLOCKEVENTS 64 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 65 select GENERIC_CLOCKEVENTS_MIN_ADJUST 66 select GENERIC_CMOS_UPDATE 67 select GENERIC_CPU_AUTOPROBE 68 select GENERIC_EARLY_IOREMAP 69 select GENERIC_FIND_FIRST_BIT 70 select GENERIC_IOMAP 71 select GENERIC_IRQ_PROBE 72 select GENERIC_IRQ_SHOW 73 select GENERIC_PENDING_IRQ if SMP 74 select GENERIC_SMP_IDLE_THREAD 75 select GENERIC_STRNCPY_FROM_USER 76 select GENERIC_STRNLEN_USER 77 select GENERIC_TIME_VSYSCALL 78 select HAVE_ACPI_APEI if ACPI 79 select HAVE_ACPI_APEI_NMI if ACPI 80 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 81 select HAVE_AOUT if X86_32 82 select HAVE_ARCH_AUDITSYSCALL 83 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 84 select HAVE_ARCH_JUMP_LABEL 85 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 86 select HAVE_ARCH_KGDB 87 select HAVE_ARCH_KMEMCHECK 88 select HAVE_ARCH_MMAP_RND_BITS if MMU 89 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 90 select HAVE_ARCH_SECCOMP_FILTER 91 select HAVE_ARCH_SOFT_DIRTY if X86_64 92 select HAVE_ARCH_TRACEHOOK 93 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 94 select HAVE_BPF_JIT if X86_64 95 select HAVE_CC_STACKPROTECTOR 96 select HAVE_CMPXCHG_DOUBLE 97 select HAVE_CMPXCHG_LOCAL 98 select HAVE_CONTEXT_TRACKING if X86_64 99 select HAVE_COPY_THREAD_TLS 100 select HAVE_C_RECORDMCOUNT 101 select HAVE_DEBUG_KMEMLEAK 102 select HAVE_DEBUG_STACKOVERFLOW 103 select HAVE_DMA_API_DEBUG 104 select HAVE_DMA_CONTIGUOUS 105 select HAVE_DYNAMIC_FTRACE 106 select HAVE_DYNAMIC_FTRACE_WITH_REGS 107 select HAVE_EFFICIENT_UNALIGNED_ACCESS 108 select HAVE_FENTRY if X86_64 109 select HAVE_FTRACE_MCOUNT_RECORD 110 select HAVE_FUNCTION_GRAPH_FP_TEST 111 select HAVE_FUNCTION_GRAPH_TRACER 112 select HAVE_FUNCTION_TRACER 113 select HAVE_GENERIC_DMA_COHERENT if X86_32 114 select HAVE_HW_BREAKPOINT 115 select HAVE_IDE 116 select HAVE_IOREMAP_PROT 117 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 118 select HAVE_IRQ_TIME_ACCOUNTING 119 select HAVE_KERNEL_BZIP2 120 select HAVE_KERNEL_GZIP 121 select HAVE_KERNEL_LZ4 122 select HAVE_KERNEL_LZMA 123 select HAVE_KERNEL_LZO 124 select HAVE_KERNEL_XZ 125 select HAVE_KPROBES 126 select HAVE_KPROBES_ON_FTRACE 127 select HAVE_KRETPROBES 128 select HAVE_KVM 129 select HAVE_LIVEPATCH if X86_64 130 select HAVE_MEMBLOCK 131 select HAVE_MEMBLOCK_NODE_MAP 132 select HAVE_MIXED_BREAKPOINTS_REGS 133 select HAVE_OPROFILE 134 select HAVE_OPTPROBES 135 select HAVE_PCSPKR_PLATFORM 136 select HAVE_PERF_EVENTS 137 select HAVE_PERF_EVENTS_NMI 138 select HAVE_PERF_REGS 139 select HAVE_PERF_USER_STACK_DUMP 140 select HAVE_REGS_AND_STACK_ACCESS_API 141 select HAVE_SYSCALL_TRACEPOINTS 142 select HAVE_UID16 if X86_32 || IA32_EMULATION 143 select HAVE_UNSTABLE_SCHED_CLOCK 144 select HAVE_USER_RETURN_NOTIFIER 145 select IRQ_FORCED_THREADING 146 select MODULES_USE_ELF_RELA if X86_64 147 select MODULES_USE_ELF_REL if X86_32 148 select OLD_SIGACTION if X86_32 149 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 150 select PERF_EVENTS 151 select RTC_LIB 152 select SPARSE_IRQ 153 select SRCU 154 select SYSCTL_EXCEPTION_TRACE 155 select USER_STACKTRACE_SUPPORT 156 select VIRT_TO_BUS 157 select X86_DEV_DMA_OPS if X86_64 158 select X86_FEATURE_NAMES if PROC_FS 159 select HAVE_STACK_VALIDATION if X86_64 160 select ARCH_USES_HIGH_VMA_FLAGS if X86_INTEL_MEMORY_PROTECTION_KEYS 161 select ARCH_HAS_PKEYS if X86_INTEL_MEMORY_PROTECTION_KEYS 162 163config INSTRUCTION_DECODER 164 def_bool y 165 depends on KPROBES || PERF_EVENTS || UPROBES 166 167config PERF_EVENTS_INTEL_UNCORE 168 def_bool y 169 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI 170 171config OUTPUT_FORMAT 172 string 173 default "elf32-i386" if X86_32 174 default "elf64-x86-64" if X86_64 175 176config ARCH_DEFCONFIG 177 string 178 default "arch/x86/configs/i386_defconfig" if X86_32 179 default "arch/x86/configs/x86_64_defconfig" if X86_64 180 181config LOCKDEP_SUPPORT 182 def_bool y 183 184config STACKTRACE_SUPPORT 185 def_bool y 186 187config MMU 188 def_bool y 189 190config ARCH_MMAP_RND_BITS_MIN 191 default 28 if 64BIT 192 default 8 193 194config ARCH_MMAP_RND_BITS_MAX 195 default 32 if 64BIT 196 default 16 197 198config ARCH_MMAP_RND_COMPAT_BITS_MIN 199 default 8 200 201config ARCH_MMAP_RND_COMPAT_BITS_MAX 202 default 16 203 204config SBUS 205 bool 206 207config NEED_DMA_MAP_STATE 208 def_bool y 209 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 210 211config NEED_SG_DMA_LENGTH 212 def_bool y 213 214config GENERIC_ISA_DMA 215 def_bool y 216 depends on ISA_DMA_API 217 218config GENERIC_BUG 219 def_bool y 220 depends on BUG 221 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 222 223config GENERIC_BUG_RELATIVE_POINTERS 224 bool 225 226config GENERIC_HWEIGHT 227 def_bool y 228 229config ARCH_MAY_HAVE_PC_FDC 230 def_bool y 231 depends on ISA_DMA_API 232 233config RWSEM_XCHGADD_ALGORITHM 234 def_bool y 235 236config GENERIC_CALIBRATE_DELAY 237 def_bool y 238 239config ARCH_HAS_CPU_RELAX 240 def_bool y 241 242config ARCH_HAS_CACHE_LINE_SIZE 243 def_bool y 244 245config HAVE_SETUP_PER_CPU_AREA 246 def_bool y 247 248config NEED_PER_CPU_EMBED_FIRST_CHUNK 249 def_bool y 250 251config NEED_PER_CPU_PAGE_FIRST_CHUNK 252 def_bool y 253 254config ARCH_HIBERNATION_POSSIBLE 255 def_bool y 256 257config ARCH_SUSPEND_POSSIBLE 258 def_bool y 259 260config ARCH_WANT_HUGE_PMD_SHARE 261 def_bool y 262 263config ARCH_WANT_GENERAL_HUGETLB 264 def_bool y 265 266config ZONE_DMA32 267 def_bool y if X86_64 268 269config AUDIT_ARCH 270 def_bool y if X86_64 271 272config ARCH_SUPPORTS_OPTIMIZED_INLINING 273 def_bool y 274 275config ARCH_SUPPORTS_DEBUG_PAGEALLOC 276 def_bool y 277 278config KASAN_SHADOW_OFFSET 279 hex 280 depends on KASAN 281 default 0xdffffc0000000000 282 283config HAVE_INTEL_TXT 284 def_bool y 285 depends on INTEL_IOMMU && ACPI 286 287config X86_32_SMP 288 def_bool y 289 depends on X86_32 && SMP 290 291config X86_64_SMP 292 def_bool y 293 depends on X86_64 && SMP 294 295config X86_32_LAZY_GS 296 def_bool y 297 depends on X86_32 && !CC_STACKPROTECTOR 298 299config ARCH_HWEIGHT_CFLAGS 300 string 301 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 302 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 303 304config ARCH_SUPPORTS_UPROBES 305 def_bool y 306 307config FIX_EARLYCON_MEM 308 def_bool y 309 310config DEBUG_RODATA 311 def_bool y 312 313config PGTABLE_LEVELS 314 int 315 default 4 if X86_64 316 default 3 if X86_PAE 317 default 2 318 319source "init/Kconfig" 320source "kernel/Kconfig.freezer" 321 322menu "Processor type and features" 323 324config ZONE_DMA 325 bool "DMA memory allocation support" if EXPERT 326 default y 327 help 328 DMA memory allocation support allows devices with less than 32-bit 329 addressing to allocate within the first 16MB of address space. 330 Disable if no such devices will be used. 331 332 If unsure, say Y. 333 334config SMP 335 bool "Symmetric multi-processing support" 336 ---help--- 337 This enables support for systems with more than one CPU. If you have 338 a system with only one CPU, say N. If you have a system with more 339 than one CPU, say Y. 340 341 If you say N here, the kernel will run on uni- and multiprocessor 342 machines, but will use only one CPU of a multiprocessor machine. If 343 you say Y here, the kernel will run on many, but not all, 344 uniprocessor machines. On a uniprocessor machine, the kernel 345 will run faster if you say N here. 346 347 Note that if you say Y here and choose architecture "586" or 348 "Pentium" under "Processor family", the kernel will not work on 486 349 architectures. Similarly, multiprocessor kernels for the "PPro" 350 architecture may not work on all Pentium based boards. 351 352 People using multiprocessor machines who say Y here should also say 353 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 354 Management" code will be disabled if you say Y here. 355 356 See also <file:Documentation/x86/i386/IO-APIC.txt>, 357 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 358 <http://www.tldp.org/docs.html#howto>. 359 360 If you don't know what to do here, say N. 361 362config X86_FEATURE_NAMES 363 bool "Processor feature human-readable names" if EMBEDDED 364 default y 365 ---help--- 366 This option compiles in a table of x86 feature bits and corresponding 367 names. This is required to support /proc/cpuinfo and a few kernel 368 messages. You can disable this to save space, at the expense of 369 making those few kernel messages show numeric feature bits instead. 370 371 If in doubt, say Y. 372 373config X86_FAST_FEATURE_TESTS 374 bool "Fast CPU feature tests" if EMBEDDED 375 default y 376 ---help--- 377 Some fast-paths in the kernel depend on the capabilities of the CPU. 378 Say Y here for the kernel to patch in the appropriate code at runtime 379 based on the capabilities of the CPU. The infrastructure for patching 380 code at runtime takes up some additional space; space-constrained 381 embedded systems may wish to say N here to produce smaller, slightly 382 slower code. 383 384config X86_X2APIC 385 bool "Support x2apic" 386 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 387 ---help--- 388 This enables x2apic support on CPUs that have this feature. 389 390 This allows 32-bit apic IDs (so it can support very large systems), 391 and accesses the local apic via MSRs not via mmio. 392 393 If you don't know what to do here, say N. 394 395config X86_MPPARSE 396 bool "Enable MPS table" if ACPI || SFI 397 default y 398 depends on X86_LOCAL_APIC 399 ---help--- 400 For old smp systems that do not have proper acpi support. Newer systems 401 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 402 403config X86_BIGSMP 404 bool "Support for big SMP systems with more than 8 CPUs" 405 depends on X86_32 && SMP 406 ---help--- 407 This option is needed for the systems that have more than 8 CPUs 408 409config GOLDFISH 410 def_bool y 411 depends on X86_GOLDFISH 412 413if X86_32 414config X86_EXTENDED_PLATFORM 415 bool "Support for extended (non-PC) x86 platforms" 416 default y 417 ---help--- 418 If you disable this option then the kernel will only support 419 standard PC platforms. (which covers the vast majority of 420 systems out there.) 421 422 If you enable this option then you'll be able to select support 423 for the following (non-PC) 32 bit x86 platforms: 424 Goldfish (Android emulator) 425 AMD Elan 426 RDC R-321x SoC 427 SGI 320/540 (Visual Workstation) 428 STA2X11-based (e.g. Northville) 429 Moorestown MID devices 430 431 If you have one of these systems, or if you want to build a 432 generic distribution kernel, say Y here - otherwise say N. 433endif 434 435if X86_64 436config X86_EXTENDED_PLATFORM 437 bool "Support for extended (non-PC) x86 platforms" 438 default y 439 ---help--- 440 If you disable this option then the kernel will only support 441 standard PC platforms. (which covers the vast majority of 442 systems out there.) 443 444 If you enable this option then you'll be able to select support 445 for the following (non-PC) 64 bit x86 platforms: 446 Numascale NumaChip 447 ScaleMP vSMP 448 SGI Ultraviolet 449 450 If you have one of these systems, or if you want to build a 451 generic distribution kernel, say Y here - otherwise say N. 452endif 453# This is an alphabetically sorted list of 64 bit extended platforms 454# Please maintain the alphabetic order if and when there are additions 455config X86_NUMACHIP 456 bool "Numascale NumaChip" 457 depends on X86_64 458 depends on X86_EXTENDED_PLATFORM 459 depends on NUMA 460 depends on SMP 461 depends on X86_X2APIC 462 depends on PCI_MMCONFIG 463 ---help--- 464 Adds support for Numascale NumaChip large-SMP systems. Needed to 465 enable more than ~168 cores. 466 If you don't have one of these, you should say N here. 467 468config X86_VSMP 469 bool "ScaleMP vSMP" 470 select HYPERVISOR_GUEST 471 select PARAVIRT 472 depends on X86_64 && PCI 473 depends on X86_EXTENDED_PLATFORM 474 depends on SMP 475 ---help--- 476 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 477 supposed to run on these EM64T-based machines. Only choose this option 478 if you have one of these machines. 479 480config X86_UV 481 bool "SGI Ultraviolet" 482 depends on X86_64 483 depends on X86_EXTENDED_PLATFORM 484 depends on NUMA 485 depends on EFI 486 depends on X86_X2APIC 487 depends on PCI 488 ---help--- 489 This option is needed in order to support SGI Ultraviolet systems. 490 If you don't have one of these, you should say N here. 491 492# Following is an alphabetically sorted list of 32 bit extended platforms 493# Please maintain the alphabetic order if and when there are additions 494 495config X86_GOLDFISH 496 bool "Goldfish (Virtual Platform)" 497 depends on X86_EXTENDED_PLATFORM 498 ---help--- 499 Enable support for the Goldfish virtual platform used primarily 500 for Android development. Unless you are building for the Android 501 Goldfish emulator say N here. 502 503config X86_INTEL_CE 504 bool "CE4100 TV platform" 505 depends on PCI 506 depends on PCI_GODIRECT 507 depends on X86_IO_APIC 508 depends on X86_32 509 depends on X86_EXTENDED_PLATFORM 510 select X86_REBOOTFIXUPS 511 select OF 512 select OF_EARLY_FLATTREE 513 ---help--- 514 Select for the Intel CE media processor (CE4100) SOC. 515 This option compiles in support for the CE4100 SOC for settop 516 boxes and media devices. 517 518config X86_INTEL_MID 519 bool "Intel MID platform support" 520 depends on X86_EXTENDED_PLATFORM 521 depends on X86_PLATFORM_DEVICES 522 depends on PCI 523 depends on X86_64 || (PCI_GOANY && X86_32) 524 depends on X86_IO_APIC 525 select SFI 526 select I2C 527 select DW_APB_TIMER 528 select APB_TIMER 529 select INTEL_SCU_IPC 530 select MFD_INTEL_MSIC 531 ---help--- 532 Select to build a kernel capable of supporting Intel MID (Mobile 533 Internet Device) platform systems which do not have the PCI legacy 534 interfaces. If you are building for a PC class system say N here. 535 536 Intel MID platforms are based on an Intel processor and chipset which 537 consume less power than most of the x86 derivatives. 538 539config X86_INTEL_QUARK 540 bool "Intel Quark platform support" 541 depends on X86_32 542 depends on X86_EXTENDED_PLATFORM 543 depends on X86_PLATFORM_DEVICES 544 depends on X86_TSC 545 depends on PCI 546 depends on PCI_GOANY 547 depends on X86_IO_APIC 548 select IOSF_MBI 549 select INTEL_IMR 550 select COMMON_CLK 551 ---help--- 552 Select to include support for Quark X1000 SoC. 553 Say Y here if you have a Quark based system such as the Arduino 554 compatible Intel Galileo. 555 556config X86_INTEL_LPSS 557 bool "Intel Low Power Subsystem Support" 558 depends on X86 && ACPI 559 select COMMON_CLK 560 select PINCTRL 561 select IOSF_MBI 562 ---help--- 563 Select to build support for Intel Low Power Subsystem such as 564 found on Intel Lynxpoint PCH. Selecting this option enables 565 things like clock tree (common clock framework) and pincontrol 566 which are needed by the LPSS peripheral drivers. 567 568config X86_AMD_PLATFORM_DEVICE 569 bool "AMD ACPI2Platform devices support" 570 depends on ACPI 571 select COMMON_CLK 572 select PINCTRL 573 ---help--- 574 Select to interpret AMD specific ACPI device to platform device 575 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 576 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 577 implemented under PINCTRL subsystem. 578 579config IOSF_MBI 580 tristate "Intel SoC IOSF Sideband support for SoC platforms" 581 depends on PCI 582 ---help--- 583 This option enables sideband register access support for Intel SoC 584 platforms. On these platforms the IOSF sideband is used in lieu of 585 MSR's for some register accesses, mostly but not limited to thermal 586 and power. Drivers may query the availability of this device to 587 determine if they need the sideband in order to work on these 588 platforms. The sideband is available on the following SoC products. 589 This list is not meant to be exclusive. 590 - BayTrail 591 - Braswell 592 - Quark 593 594 You should say Y if you are running a kernel on one of these SoC's. 595 596config IOSF_MBI_DEBUG 597 bool "Enable IOSF sideband access through debugfs" 598 depends on IOSF_MBI && DEBUG_FS 599 ---help--- 600 Select this option to expose the IOSF sideband access registers (MCR, 601 MDR, MCRX) through debugfs to write and read register information from 602 different units on the SoC. This is most useful for obtaining device 603 state information for debug and analysis. As this is a general access 604 mechanism, users of this option would have specific knowledge of the 605 device they want to access. 606 607 If you don't require the option or are in doubt, say N. 608 609config X86_RDC321X 610 bool "RDC R-321x SoC" 611 depends on X86_32 612 depends on X86_EXTENDED_PLATFORM 613 select M486 614 select X86_REBOOTFIXUPS 615 ---help--- 616 This option is needed for RDC R-321x system-on-chip, also known 617 as R-8610-(G). 618 If you don't have one of these chips, you should say N here. 619 620config X86_32_NON_STANDARD 621 bool "Support non-standard 32-bit SMP architectures" 622 depends on X86_32 && SMP 623 depends on X86_EXTENDED_PLATFORM 624 ---help--- 625 This option compiles in the bigsmp and STA2X11 default 626 subarchitectures. It is intended for a generic binary 627 kernel. If you select them all, kernel will probe it one by 628 one and will fallback to default. 629 630# Alphabetically sorted list of Non standard 32 bit platforms 631 632config X86_SUPPORTS_MEMORY_FAILURE 633 def_bool y 634 # MCE code calls memory_failure(): 635 depends on X86_MCE 636 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 637 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 638 depends on X86_64 || !SPARSEMEM 639 select ARCH_SUPPORTS_MEMORY_FAILURE 640 641config STA2X11 642 bool "STA2X11 Companion Chip Support" 643 depends on X86_32_NON_STANDARD && PCI 644 select X86_DEV_DMA_OPS 645 select X86_DMA_REMAP 646 select SWIOTLB 647 select MFD_STA2X11 648 select ARCH_REQUIRE_GPIOLIB 649 default n 650 ---help--- 651 This adds support for boards based on the STA2X11 IO-Hub, 652 a.k.a. "ConneXt". The chip is used in place of the standard 653 PC chipset, so all "standard" peripherals are missing. If this 654 option is selected the kernel will still be able to boot on 655 standard PC machines. 656 657config X86_32_IRIS 658 tristate "Eurobraille/Iris poweroff module" 659 depends on X86_32 660 ---help--- 661 The Iris machines from EuroBraille do not have APM or ACPI support 662 to shut themselves down properly. A special I/O sequence is 663 needed to do so, which is what this module does at 664 kernel shutdown. 665 666 This is only for Iris machines from EuroBraille. 667 668 If unused, say N. 669 670config SCHED_OMIT_FRAME_POINTER 671 def_bool y 672 prompt "Single-depth WCHAN output" 673 depends on X86 674 ---help--- 675 Calculate simpler /proc/<PID>/wchan values. If this option 676 is disabled then wchan values will recurse back to the 677 caller function. This provides more accurate wchan values, 678 at the expense of slightly more scheduling overhead. 679 680 If in doubt, say "Y". 681 682menuconfig HYPERVISOR_GUEST 683 bool "Linux guest support" 684 ---help--- 685 Say Y here to enable options for running Linux under various hyper- 686 visors. This option enables basic hypervisor detection and platform 687 setup. 688 689 If you say N, all options in this submenu will be skipped and 690 disabled, and Linux guest support won't be built in. 691 692if HYPERVISOR_GUEST 693 694config PARAVIRT 695 bool "Enable paravirtualization code" 696 ---help--- 697 This changes the kernel so it can modify itself when it is run 698 under a hypervisor, potentially improving performance significantly 699 over full virtualization. However, when run without a hypervisor 700 the kernel is theoretically slower and slightly larger. 701 702config PARAVIRT_DEBUG 703 bool "paravirt-ops debugging" 704 depends on PARAVIRT && DEBUG_KERNEL 705 ---help--- 706 Enable to debug paravirt_ops internals. Specifically, BUG if 707 a paravirt_op is missing when it is called. 708 709config PARAVIRT_SPINLOCKS 710 bool "Paravirtualization layer for spinlocks" 711 depends on PARAVIRT && SMP 712 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS 713 ---help--- 714 Paravirtualized spinlocks allow a pvops backend to replace the 715 spinlock implementation with something virtualization-friendly 716 (for example, block the virtual CPU rather than spinning). 717 718 It has a minimal impact on native kernels and gives a nice performance 719 benefit on paravirtualized KVM / Xen kernels. 720 721 If you are unsure how to answer this question, answer Y. 722 723config QUEUED_LOCK_STAT 724 bool "Paravirt queued spinlock statistics" 725 depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS 726 ---help--- 727 Enable the collection of statistical data on the slowpath 728 behavior of paravirtualized queued spinlocks and report 729 them on debugfs. 730 731source "arch/x86/xen/Kconfig" 732 733config KVM_GUEST 734 bool "KVM Guest support (including kvmclock)" 735 depends on PARAVIRT 736 select PARAVIRT_CLOCK 737 default y 738 ---help--- 739 This option enables various optimizations for running under the KVM 740 hypervisor. It includes a paravirtualized clock, so that instead 741 of relying on a PIT (or probably other) emulation by the 742 underlying device model, the host provides the guest with 743 timing infrastructure such as time of day, and system time 744 745config KVM_DEBUG_FS 746 bool "Enable debug information for KVM Guests in debugfs" 747 depends on KVM_GUEST && DEBUG_FS 748 default n 749 ---help--- 750 This option enables collection of various statistics for KVM guest. 751 Statistics are displayed in debugfs filesystem. Enabling this option 752 may incur significant overhead. 753 754source "arch/x86/lguest/Kconfig" 755 756config PARAVIRT_TIME_ACCOUNTING 757 bool "Paravirtual steal time accounting" 758 depends on PARAVIRT 759 default n 760 ---help--- 761 Select this option to enable fine granularity task steal time 762 accounting. Time spent executing other tasks in parallel with 763 the current vCPU is discounted from the vCPU power. To account for 764 that, there can be a small performance impact. 765 766 If in doubt, say N here. 767 768config PARAVIRT_CLOCK 769 bool 770 771endif #HYPERVISOR_GUEST 772 773config NO_BOOTMEM 774 def_bool y 775 776source "arch/x86/Kconfig.cpu" 777 778config HPET_TIMER 779 def_bool X86_64 780 prompt "HPET Timer Support" if X86_32 781 ---help--- 782 Use the IA-PC HPET (High Precision Event Timer) to manage 783 time in preference to the PIT and RTC, if a HPET is 784 present. 785 HPET is the next generation timer replacing legacy 8254s. 786 The HPET provides a stable time base on SMP 787 systems, unlike the TSC, but it is more expensive to access, 788 as it is off-chip. The interface used is documented 789 in the HPET spec, revision 1. 790 791 You can safely choose Y here. However, HPET will only be 792 activated if the platform and the BIOS support this feature. 793 Otherwise the 8254 will be used for timing services. 794 795 Choose N to continue using the legacy 8254 timer. 796 797config HPET_EMULATE_RTC 798 def_bool y 799 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 800 801config APB_TIMER 802 def_bool y if X86_INTEL_MID 803 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 804 select DW_APB_TIMER 805 depends on X86_INTEL_MID && SFI 806 help 807 APB timer is the replacement for 8254, HPET on X86 MID platforms. 808 The APBT provides a stable time base on SMP 809 systems, unlike the TSC, but it is more expensive to access, 810 as it is off-chip. APB timers are always running regardless of CPU 811 C states, they are used as per CPU clockevent device when possible. 812 813# Mark as expert because too many people got it wrong. 814# The code disables itself when not needed. 815config DMI 816 default y 817 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 818 bool "Enable DMI scanning" if EXPERT 819 ---help--- 820 Enabled scanning of DMI to identify machine quirks. Say Y 821 here unless you have verified that your setup is not 822 affected by entries in the DMI blacklist. Required by PNP 823 BIOS code. 824 825config GART_IOMMU 826 bool "Old AMD GART IOMMU support" 827 select SWIOTLB 828 depends on X86_64 && PCI && AMD_NB 829 ---help--- 830 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 831 GART based hardware IOMMUs. 832 833 The GART supports full DMA access for devices with 32-bit access 834 limitations, on systems with more than 3 GB. This is usually needed 835 for USB, sound, many IDE/SATA chipsets and some other devices. 836 837 Newer systems typically have a modern AMD IOMMU, supported via 838 the CONFIG_AMD_IOMMU=y config option. 839 840 In normal configurations this driver is only active when needed: 841 there's more than 3 GB of memory and the system contains a 842 32-bit limited device. 843 844 If unsure, say Y. 845 846config CALGARY_IOMMU 847 bool "IBM Calgary IOMMU support" 848 select SWIOTLB 849 depends on X86_64 && PCI 850 ---help--- 851 Support for hardware IOMMUs in IBM's xSeries x366 and x460 852 systems. Needed to run systems with more than 3GB of memory 853 properly with 32-bit PCI devices that do not support DAC 854 (Double Address Cycle). Calgary also supports bus level 855 isolation, where all DMAs pass through the IOMMU. This 856 prevents them from going anywhere except their intended 857 destination. This catches hard-to-find kernel bugs and 858 mis-behaving drivers and devices that do not use the DMA-API 859 properly to set up their DMA buffers. The IOMMU can be 860 turned off at boot time with the iommu=off parameter. 861 Normally the kernel will make the right choice by itself. 862 If unsure, say Y. 863 864config CALGARY_IOMMU_ENABLED_BY_DEFAULT 865 def_bool y 866 prompt "Should Calgary be enabled by default?" 867 depends on CALGARY_IOMMU 868 ---help--- 869 Should Calgary be enabled by default? if you choose 'y', Calgary 870 will be used (if it exists). If you choose 'n', Calgary will not be 871 used even if it exists. If you choose 'n' and would like to use 872 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 873 If unsure, say Y. 874 875# need this always selected by IOMMU for the VIA workaround 876config SWIOTLB 877 def_bool y if X86_64 878 ---help--- 879 Support for software bounce buffers used on x86-64 systems 880 which don't have a hardware IOMMU. Using this PCI devices 881 which can only access 32-bits of memory can be used on systems 882 with more than 3 GB of memory. 883 If unsure, say Y. 884 885config IOMMU_HELPER 886 def_bool y 887 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 888 889config MAXSMP 890 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 891 depends on X86_64 && SMP && DEBUG_KERNEL 892 select CPUMASK_OFFSTACK 893 ---help--- 894 Enable maximum number of CPUS and NUMA Nodes for this architecture. 895 If unsure, say N. 896 897config NR_CPUS 898 int "Maximum number of CPUs" if SMP && !MAXSMP 899 range 2 8 if SMP && X86_32 && !X86_BIGSMP 900 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 901 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 902 default "1" if !SMP 903 default "8192" if MAXSMP 904 default "32" if SMP && X86_BIGSMP 905 default "8" if SMP && X86_32 906 default "64" if SMP 907 ---help--- 908 This allows you to specify the maximum number of CPUs which this 909 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 910 supported value is 8192, otherwise the maximum value is 512. The 911 minimum value which makes sense is 2. 912 913 This is purely to save memory - each supported CPU adds 914 approximately eight kilobytes to the kernel image. 915 916config SCHED_SMT 917 bool "SMT (Hyperthreading) scheduler support" 918 depends on SMP 919 ---help--- 920 SMT scheduler support improves the CPU scheduler's decision making 921 when dealing with Intel Pentium 4 chips with HyperThreading at a 922 cost of slightly increased overhead in some places. If unsure say 923 N here. 924 925config SCHED_MC 926 def_bool y 927 prompt "Multi-core scheduler support" 928 depends on SMP 929 ---help--- 930 Multi-core scheduler support improves the CPU scheduler's decision 931 making when dealing with multi-core CPU chips at a cost of slightly 932 increased overhead in some places. If unsure say N here. 933 934source "kernel/Kconfig.preempt" 935 936config UP_LATE_INIT 937 def_bool y 938 depends on !SMP && X86_LOCAL_APIC 939 940config X86_UP_APIC 941 bool "Local APIC support on uniprocessors" if !PCI_MSI 942 default PCI_MSI 943 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 944 ---help--- 945 A local APIC (Advanced Programmable Interrupt Controller) is an 946 integrated interrupt controller in the CPU. If you have a single-CPU 947 system which has a processor with a local APIC, you can say Y here to 948 enable and use it. If you say Y here even though your machine doesn't 949 have a local APIC, then the kernel will still run with no slowdown at 950 all. The local APIC supports CPU-generated self-interrupts (timer, 951 performance counters), and the NMI watchdog which detects hard 952 lockups. 953 954config X86_UP_IOAPIC 955 bool "IO-APIC support on uniprocessors" 956 depends on X86_UP_APIC 957 ---help--- 958 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 959 SMP-capable replacement for PC-style interrupt controllers. Most 960 SMP systems and many recent uniprocessor systems have one. 961 962 If you have a single-CPU system with an IO-APIC, you can say Y here 963 to use it. If you say Y here even though your machine doesn't have 964 an IO-APIC, then the kernel will still run with no slowdown at all. 965 966config X86_LOCAL_APIC 967 def_bool y 968 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 969 select IRQ_DOMAIN_HIERARCHY 970 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 971 972config X86_IO_APIC 973 def_bool y 974 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 975 976config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 977 bool "Reroute for broken boot IRQs" 978 depends on X86_IO_APIC 979 ---help--- 980 This option enables a workaround that fixes a source of 981 spurious interrupts. This is recommended when threaded 982 interrupt handling is used on systems where the generation of 983 superfluous "boot interrupts" cannot be disabled. 984 985 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 986 entry in the chipset's IO-APIC is masked (as, e.g. the RT 987 kernel does during interrupt handling). On chipsets where this 988 boot IRQ generation cannot be disabled, this workaround keeps 989 the original IRQ line masked so that only the equivalent "boot 990 IRQ" is delivered to the CPUs. The workaround also tells the 991 kernel to set up the IRQ handler on the boot IRQ line. In this 992 way only one interrupt is delivered to the kernel. Otherwise 993 the spurious second interrupt may cause the kernel to bring 994 down (vital) interrupt lines. 995 996 Only affects "broken" chipsets. Interrupt sharing may be 997 increased on these systems. 998 999config X86_MCE 1000 bool "Machine Check / overheating reporting" 1001 select GENERIC_ALLOCATOR 1002 default y 1003 ---help--- 1004 Machine Check support allows the processor to notify the 1005 kernel if it detects a problem (e.g. overheating, data corruption). 1006 The action the kernel takes depends on the severity of the problem, 1007 ranging from warning messages to halting the machine. 1008 1009config X86_MCE_INTEL 1010 def_bool y 1011 prompt "Intel MCE features" 1012 depends on X86_MCE && X86_LOCAL_APIC 1013 ---help--- 1014 Additional support for intel specific MCE features such as 1015 the thermal monitor. 1016 1017config X86_MCE_AMD 1018 def_bool y 1019 prompt "AMD MCE features" 1020 depends on X86_MCE && X86_LOCAL_APIC 1021 ---help--- 1022 Additional support for AMD specific MCE features such as 1023 the DRAM Error Threshold. 1024 1025config X86_ANCIENT_MCE 1026 bool "Support for old Pentium 5 / WinChip machine checks" 1027 depends on X86_32 && X86_MCE 1028 ---help--- 1029 Include support for machine check handling on old Pentium 5 or WinChip 1030 systems. These typically need to be enabled explicitly on the command 1031 line. 1032 1033config X86_MCE_THRESHOLD 1034 depends on X86_MCE_AMD || X86_MCE_INTEL 1035 def_bool y 1036 1037config X86_MCE_INJECT 1038 depends on X86_MCE 1039 tristate "Machine check injector support" 1040 ---help--- 1041 Provide support for injecting machine checks for testing purposes. 1042 If you don't know what a machine check is and you don't do kernel 1043 QA it is safe to say n. 1044 1045config X86_THERMAL_VECTOR 1046 def_bool y 1047 depends on X86_MCE_INTEL 1048 1049config X86_LEGACY_VM86 1050 bool "Legacy VM86 support" 1051 default n 1052 depends on X86_32 1053 ---help--- 1054 This option allows user programs to put the CPU into V8086 1055 mode, which is an 80286-era approximation of 16-bit real mode. 1056 1057 Some very old versions of X and/or vbetool require this option 1058 for user mode setting. Similarly, DOSEMU will use it if 1059 available to accelerate real mode DOS programs. However, any 1060 recent version of DOSEMU, X, or vbetool should be fully 1061 functional even without kernel VM86 support, as they will all 1062 fall back to software emulation. Nevertheless, if you are using 1063 a 16-bit DOS program where 16-bit performance matters, vm86 1064 mode might be faster than emulation and you might want to 1065 enable this option. 1066 1067 Note that any app that works on a 64-bit kernel is unlikely to 1068 need this option, as 64-bit kernels don't, and can't, support 1069 V8086 mode. This option is also unrelated to 16-bit protected 1070 mode and is not needed to run most 16-bit programs under Wine. 1071 1072 Enabling this option increases the complexity of the kernel 1073 and slows down exception handling a tiny bit. 1074 1075 If unsure, say N here. 1076 1077config VM86 1078 bool 1079 default X86_LEGACY_VM86 1080 1081config X86_16BIT 1082 bool "Enable support for 16-bit segments" if EXPERT 1083 default y 1084 depends on MODIFY_LDT_SYSCALL 1085 ---help--- 1086 This option is required by programs like Wine to run 16-bit 1087 protected mode legacy code on x86 processors. Disabling 1088 this option saves about 300 bytes on i386, or around 6K text 1089 plus 16K runtime memory on x86-64, 1090 1091config X86_ESPFIX32 1092 def_bool y 1093 depends on X86_16BIT && X86_32 1094 1095config X86_ESPFIX64 1096 def_bool y 1097 depends on X86_16BIT && X86_64 1098 1099config X86_VSYSCALL_EMULATION 1100 bool "Enable vsyscall emulation" if EXPERT 1101 default y 1102 depends on X86_64 1103 ---help--- 1104 This enables emulation of the legacy vsyscall page. Disabling 1105 it is roughly equivalent to booting with vsyscall=none, except 1106 that it will also disable the helpful warning if a program 1107 tries to use a vsyscall. With this option set to N, offending 1108 programs will just segfault, citing addresses of the form 1109 0xffffffffff600?00. 1110 1111 This option is required by many programs built before 2013, and 1112 care should be used even with newer programs if set to N. 1113 1114 Disabling this option saves about 7K of kernel size and 1115 possibly 4K of additional runtime pagetable memory. 1116 1117config TOSHIBA 1118 tristate "Toshiba Laptop support" 1119 depends on X86_32 1120 ---help--- 1121 This adds a driver to safely access the System Management Mode of 1122 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1123 not work on models with a Phoenix BIOS. The System Management Mode 1124 is used to set the BIOS and power saving options on Toshiba portables. 1125 1126 For information on utilities to make use of this driver see the 1127 Toshiba Linux utilities web site at: 1128 <http://www.buzzard.org.uk/toshiba/>. 1129 1130 Say Y if you intend to run this kernel on a Toshiba portable. 1131 Say N otherwise. 1132 1133config I8K 1134 tristate "Dell i8k legacy laptop support" 1135 select HWMON 1136 select SENSORS_DELL_SMM 1137 ---help--- 1138 This option enables legacy /proc/i8k userspace interface in hwmon 1139 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1140 temperature and allows controlling fan speeds of Dell laptops via 1141 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1142 it reports also power and hotkey status. For fan speed control is 1143 needed userspace package i8kutils. 1144 1145 Say Y if you intend to run this kernel on old Dell laptops or want to 1146 use userspace package i8kutils. 1147 Say N otherwise. 1148 1149config X86_REBOOTFIXUPS 1150 bool "Enable X86 board specific fixups for reboot" 1151 depends on X86_32 1152 ---help--- 1153 This enables chipset and/or board specific fixups to be done 1154 in order to get reboot to work correctly. This is only needed on 1155 some combinations of hardware and BIOS. The symptom, for which 1156 this config is intended, is when reboot ends with a stalled/hung 1157 system. 1158 1159 Currently, the only fixup is for the Geode machines using 1160 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1161 1162 Say Y if you want to enable the fixup. Currently, it's safe to 1163 enable this option even if you don't need it. 1164 Say N otherwise. 1165 1166config MICROCODE 1167 bool "CPU microcode loading support" 1168 default y 1169 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1170 select FW_LOADER 1171 ---help--- 1172 If you say Y here, you will be able to update the microcode on 1173 Intel and AMD processors. The Intel support is for the IA32 family, 1174 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1175 AMD support is for families 0x10 and later. You will obviously need 1176 the actual microcode binary data itself which is not shipped with 1177 the Linux kernel. 1178 1179 The preferred method to load microcode from a detached initrd is described 1180 in Documentation/x86/early-microcode.txt. For that you need to enable 1181 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1182 initrd for microcode blobs. 1183 1184 In addition, you can build-in the microcode into the kernel. For that you 1185 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 1186 to the CONFIG_EXTRA_FIRMWARE config option. 1187 1188config MICROCODE_INTEL 1189 bool "Intel microcode loading support" 1190 depends on MICROCODE 1191 default MICROCODE 1192 select FW_LOADER 1193 ---help--- 1194 This options enables microcode patch loading support for Intel 1195 processors. 1196 1197 For the current Intel microcode data package go to 1198 <https://downloadcenter.intel.com> and search for 1199 'Linux Processor Microcode Data File'. 1200 1201config MICROCODE_AMD 1202 bool "AMD microcode loading support" 1203 depends on MICROCODE 1204 select FW_LOADER 1205 ---help--- 1206 If you select this option, microcode patch loading support for AMD 1207 processors will be enabled. 1208 1209config MICROCODE_OLD_INTERFACE 1210 def_bool y 1211 depends on MICROCODE 1212 1213config PERF_EVENTS_AMD_POWER 1214 depends on PERF_EVENTS && CPU_SUP_AMD 1215 tristate "AMD Processor Power Reporting Mechanism" 1216 ---help--- 1217 Provide power reporting mechanism support for AMD processors. 1218 Currently, it leverages X86_FEATURE_ACC_POWER 1219 (CPUID Fn8000_0007_EDX[12]) interface to calculate the 1220 average power consumption on Family 15h processors. 1221 1222config X86_MSR 1223 tristate "/dev/cpu/*/msr - Model-specific register support" 1224 ---help--- 1225 This device gives privileged processes access to the x86 1226 Model-Specific Registers (MSRs). It is a character device with 1227 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1228 MSR accesses are directed to a specific CPU on multi-processor 1229 systems. 1230 1231config X86_CPUID 1232 tristate "/dev/cpu/*/cpuid - CPU information support" 1233 ---help--- 1234 This device gives processes access to the x86 CPUID instruction to 1235 be executed on a specific processor. It is a character device 1236 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1237 /dev/cpu/31/cpuid. 1238 1239choice 1240 prompt "High Memory Support" 1241 default HIGHMEM4G 1242 depends on X86_32 1243 1244config NOHIGHMEM 1245 bool "off" 1246 ---help--- 1247 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1248 However, the address space of 32-bit x86 processors is only 4 1249 Gigabytes large. That means that, if you have a large amount of 1250 physical memory, not all of it can be "permanently mapped" by the 1251 kernel. The physical memory that's not permanently mapped is called 1252 "high memory". 1253 1254 If you are compiling a kernel which will never run on a machine with 1255 more than 1 Gigabyte total physical RAM, answer "off" here (default 1256 choice and suitable for most users). This will result in a "3GB/1GB" 1257 split: 3GB are mapped so that each process sees a 3GB virtual memory 1258 space and the remaining part of the 4GB virtual memory space is used 1259 by the kernel to permanently map as much physical memory as 1260 possible. 1261 1262 If the machine has between 1 and 4 Gigabytes physical RAM, then 1263 answer "4GB" here. 1264 1265 If more than 4 Gigabytes is used then answer "64GB" here. This 1266 selection turns Intel PAE (Physical Address Extension) mode on. 1267 PAE implements 3-level paging on IA32 processors. PAE is fully 1268 supported by Linux, PAE mode is implemented on all recent Intel 1269 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1270 then the kernel will not boot on CPUs that don't support PAE! 1271 1272 The actual amount of total physical memory will either be 1273 auto detected or can be forced by using a kernel command line option 1274 such as "mem=256M". (Try "man bootparam" or see the documentation of 1275 your boot loader (lilo or loadlin) about how to pass options to the 1276 kernel at boot time.) 1277 1278 If unsure, say "off". 1279 1280config HIGHMEM4G 1281 bool "4GB" 1282 ---help--- 1283 Select this if you have a 32-bit processor and between 1 and 4 1284 gigabytes of physical RAM. 1285 1286config HIGHMEM64G 1287 bool "64GB" 1288 depends on !M486 1289 select X86_PAE 1290 ---help--- 1291 Select this if you have a 32-bit processor and more than 4 1292 gigabytes of physical RAM. 1293 1294endchoice 1295 1296choice 1297 prompt "Memory split" if EXPERT 1298 default VMSPLIT_3G 1299 depends on X86_32 1300 ---help--- 1301 Select the desired split between kernel and user memory. 1302 1303 If the address range available to the kernel is less than the 1304 physical memory installed, the remaining memory will be available 1305 as "high memory". Accessing high memory is a little more costly 1306 than low memory, as it needs to be mapped into the kernel first. 1307 Note that increasing the kernel address space limits the range 1308 available to user programs, making the address space there 1309 tighter. Selecting anything other than the default 3G/1G split 1310 will also likely make your kernel incompatible with binary-only 1311 kernel modules. 1312 1313 If you are not absolutely sure what you are doing, leave this 1314 option alone! 1315 1316 config VMSPLIT_3G 1317 bool "3G/1G user/kernel split" 1318 config VMSPLIT_3G_OPT 1319 depends on !X86_PAE 1320 bool "3G/1G user/kernel split (for full 1G low memory)" 1321 config VMSPLIT_2G 1322 bool "2G/2G user/kernel split" 1323 config VMSPLIT_2G_OPT 1324 depends on !X86_PAE 1325 bool "2G/2G user/kernel split (for full 2G low memory)" 1326 config VMSPLIT_1G 1327 bool "1G/3G user/kernel split" 1328endchoice 1329 1330config PAGE_OFFSET 1331 hex 1332 default 0xB0000000 if VMSPLIT_3G_OPT 1333 default 0x80000000 if VMSPLIT_2G 1334 default 0x78000000 if VMSPLIT_2G_OPT 1335 default 0x40000000 if VMSPLIT_1G 1336 default 0xC0000000 1337 depends on X86_32 1338 1339config HIGHMEM 1340 def_bool y 1341 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1342 1343config X86_PAE 1344 bool "PAE (Physical Address Extension) Support" 1345 depends on X86_32 && !HIGHMEM4G 1346 select SWIOTLB 1347 ---help--- 1348 PAE is required for NX support, and furthermore enables 1349 larger swapspace support for non-overcommit purposes. It 1350 has the cost of more pagetable lookup overhead, and also 1351 consumes more pagetable space per process. 1352 1353config ARCH_PHYS_ADDR_T_64BIT 1354 def_bool y 1355 depends on X86_64 || X86_PAE 1356 1357config ARCH_DMA_ADDR_T_64BIT 1358 def_bool y 1359 depends on X86_64 || HIGHMEM64G 1360 1361config X86_DIRECT_GBPAGES 1362 def_bool y 1363 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1364 ---help--- 1365 Certain kernel features effectively disable kernel 1366 linear 1 GB mappings (even if the CPU otherwise 1367 supports them), so don't confuse the user by printing 1368 that we have them enabled. 1369 1370# Common NUMA Features 1371config NUMA 1372 bool "Numa Memory Allocation and Scheduler Support" 1373 depends on SMP 1374 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1375 default y if X86_BIGSMP 1376 ---help--- 1377 Enable NUMA (Non Uniform Memory Access) support. 1378 1379 The kernel will try to allocate memory used by a CPU on the 1380 local memory controller of the CPU and add some more 1381 NUMA awareness to the kernel. 1382 1383 For 64-bit this is recommended if the system is Intel Core i7 1384 (or later), AMD Opteron, or EM64T NUMA. 1385 1386 For 32-bit this is only needed if you boot a 32-bit 1387 kernel on a 64-bit NUMA platform. 1388 1389 Otherwise, you should say N. 1390 1391config AMD_NUMA 1392 def_bool y 1393 prompt "Old style AMD Opteron NUMA detection" 1394 depends on X86_64 && NUMA && PCI 1395 ---help--- 1396 Enable AMD NUMA node topology detection. You should say Y here if 1397 you have a multi processor AMD system. This uses an old method to 1398 read the NUMA configuration directly from the builtin Northbridge 1399 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1400 which also takes priority if both are compiled in. 1401 1402config X86_64_ACPI_NUMA 1403 def_bool y 1404 prompt "ACPI NUMA detection" 1405 depends on X86_64 && NUMA && ACPI && PCI 1406 select ACPI_NUMA 1407 ---help--- 1408 Enable ACPI SRAT based node topology detection. 1409 1410# Some NUMA nodes have memory ranges that span 1411# other nodes. Even though a pfn is valid and 1412# between a node's start and end pfns, it may not 1413# reside on that node. See memmap_init_zone() 1414# for details. 1415config NODES_SPAN_OTHER_NODES 1416 def_bool y 1417 depends on X86_64_ACPI_NUMA 1418 1419config NUMA_EMU 1420 bool "NUMA emulation" 1421 depends on NUMA 1422 ---help--- 1423 Enable NUMA emulation. A flat machine will be split 1424 into virtual nodes when booted with "numa=fake=N", where N is the 1425 number of nodes. This is only useful for debugging. 1426 1427config NODES_SHIFT 1428 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1429 range 1 10 1430 default "10" if MAXSMP 1431 default "6" if X86_64 1432 default "3" 1433 depends on NEED_MULTIPLE_NODES 1434 ---help--- 1435 Specify the maximum number of NUMA Nodes available on the target 1436 system. Increases memory reserved to accommodate various tables. 1437 1438config ARCH_HAVE_MEMORY_PRESENT 1439 def_bool y 1440 depends on X86_32 && DISCONTIGMEM 1441 1442config NEED_NODE_MEMMAP_SIZE 1443 def_bool y 1444 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1445 1446config ARCH_FLATMEM_ENABLE 1447 def_bool y 1448 depends on X86_32 && !NUMA 1449 1450config ARCH_DISCONTIGMEM_ENABLE 1451 def_bool y 1452 depends on NUMA && X86_32 1453 1454config ARCH_DISCONTIGMEM_DEFAULT 1455 def_bool y 1456 depends on NUMA && X86_32 1457 1458config ARCH_SPARSEMEM_ENABLE 1459 def_bool y 1460 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1461 select SPARSEMEM_STATIC if X86_32 1462 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1463 1464config ARCH_SPARSEMEM_DEFAULT 1465 def_bool y 1466 depends on X86_64 1467 1468config ARCH_SELECT_MEMORY_MODEL 1469 def_bool y 1470 depends on ARCH_SPARSEMEM_ENABLE 1471 1472config ARCH_MEMORY_PROBE 1473 bool "Enable sysfs memory/probe interface" 1474 depends on X86_64 && MEMORY_HOTPLUG 1475 help 1476 This option enables a sysfs memory/probe interface for testing. 1477 See Documentation/memory-hotplug.txt for more information. 1478 If you are unsure how to answer this question, answer N. 1479 1480config ARCH_PROC_KCORE_TEXT 1481 def_bool y 1482 depends on X86_64 && PROC_KCORE 1483 1484config ILLEGAL_POINTER_VALUE 1485 hex 1486 default 0 if X86_32 1487 default 0xdead000000000000 if X86_64 1488 1489source "mm/Kconfig" 1490 1491config X86_PMEM_LEGACY_DEVICE 1492 bool 1493 1494config X86_PMEM_LEGACY 1495 tristate "Support non-standard NVDIMMs and ADR protected memory" 1496 depends on PHYS_ADDR_T_64BIT 1497 depends on BLK_DEV 1498 select X86_PMEM_LEGACY_DEVICE 1499 select LIBNVDIMM 1500 help 1501 Treat memory marked using the non-standard e820 type of 12 as used 1502 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1503 The kernel will offer these regions to the 'pmem' driver so 1504 they can be used for persistent storage. 1505 1506 Say Y if unsure. 1507 1508config HIGHPTE 1509 bool "Allocate 3rd-level pagetables from highmem" 1510 depends on HIGHMEM 1511 ---help--- 1512 The VM uses one page table entry for each page of physical memory. 1513 For systems with a lot of RAM, this can be wasteful of precious 1514 low memory. Setting this option will put user-space page table 1515 entries in high memory. 1516 1517config X86_CHECK_BIOS_CORRUPTION 1518 bool "Check for low memory corruption" 1519 ---help--- 1520 Periodically check for memory corruption in low memory, which 1521 is suspected to be caused by BIOS. Even when enabled in the 1522 configuration, it is disabled at runtime. Enable it by 1523 setting "memory_corruption_check=1" on the kernel command 1524 line. By default it scans the low 64k of memory every 60 1525 seconds; see the memory_corruption_check_size and 1526 memory_corruption_check_period parameters in 1527 Documentation/kernel-parameters.txt to adjust this. 1528 1529 When enabled with the default parameters, this option has 1530 almost no overhead, as it reserves a relatively small amount 1531 of memory and scans it infrequently. It both detects corruption 1532 and prevents it from affecting the running system. 1533 1534 It is, however, intended as a diagnostic tool; if repeatable 1535 BIOS-originated corruption always affects the same memory, 1536 you can use memmap= to prevent the kernel from using that 1537 memory. 1538 1539config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1540 bool "Set the default setting of memory_corruption_check" 1541 depends on X86_CHECK_BIOS_CORRUPTION 1542 default y 1543 ---help--- 1544 Set whether the default state of memory_corruption_check is 1545 on or off. 1546 1547config X86_RESERVE_LOW 1548 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1549 default 64 1550 range 4 640 1551 ---help--- 1552 Specify the amount of low memory to reserve for the BIOS. 1553 1554 The first page contains BIOS data structures that the kernel 1555 must not use, so that page must always be reserved. 1556 1557 By default we reserve the first 64K of physical RAM, as a 1558 number of BIOSes are known to corrupt that memory range 1559 during events such as suspend/resume or monitor cable 1560 insertion, so it must not be used by the kernel. 1561 1562 You can set this to 4 if you are absolutely sure that you 1563 trust the BIOS to get all its memory reservations and usages 1564 right. If you know your BIOS have problems beyond the 1565 default 64K area, you can set this to 640 to avoid using the 1566 entire low memory range. 1567 1568 If you have doubts about the BIOS (e.g. suspend/resume does 1569 not work or there's kernel crashes after certain hardware 1570 hotplug events) then you might want to enable 1571 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1572 typical corruption patterns. 1573 1574 Leave this to the default value of 64 if you are unsure. 1575 1576config MATH_EMULATION 1577 bool 1578 depends on MODIFY_LDT_SYSCALL 1579 prompt "Math emulation" if X86_32 1580 ---help--- 1581 Linux can emulate a math coprocessor (used for floating point 1582 operations) if you don't have one. 486DX and Pentium processors have 1583 a math coprocessor built in, 486SX and 386 do not, unless you added 1584 a 487DX or 387, respectively. (The messages during boot time can 1585 give you some hints here ["man dmesg"].) Everyone needs either a 1586 coprocessor or this emulation. 1587 1588 If you don't have a math coprocessor, you need to say Y here; if you 1589 say Y here even though you have a coprocessor, the coprocessor will 1590 be used nevertheless. (This behavior can be changed with the kernel 1591 command line option "no387", which comes handy if your coprocessor 1592 is broken. Try "man bootparam" or see the documentation of your boot 1593 loader (lilo or loadlin) about how to pass options to the kernel at 1594 boot time.) This means that it is a good idea to say Y here if you 1595 intend to use this kernel on different machines. 1596 1597 More information about the internals of the Linux math coprocessor 1598 emulation can be found in <file:arch/x86/math-emu/README>. 1599 1600 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1601 kernel, it won't hurt. 1602 1603config MTRR 1604 def_bool y 1605 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1606 ---help--- 1607 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1608 the Memory Type Range Registers (MTRRs) may be used to control 1609 processor access to memory ranges. This is most useful if you have 1610 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1611 allows bus write transfers to be combined into a larger transfer 1612 before bursting over the PCI/AGP bus. This can increase performance 1613 of image write operations 2.5 times or more. Saying Y here creates a 1614 /proc/mtrr file which may be used to manipulate your processor's 1615 MTRRs. Typically the X server should use this. 1616 1617 This code has a reasonably generic interface so that similar 1618 control registers on other processors can be easily supported 1619 as well: 1620 1621 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1622 Registers (ARRs) which provide a similar functionality to MTRRs. For 1623 these, the ARRs are used to emulate the MTRRs. 1624 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1625 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1626 write-combining. All of these processors are supported by this code 1627 and it makes sense to say Y here if you have one of them. 1628 1629 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1630 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1631 can lead to all sorts of problems, so it's good to say Y here. 1632 1633 You can safely say Y even if your machine doesn't have MTRRs, you'll 1634 just add about 9 KB to your kernel. 1635 1636 See <file:Documentation/x86/mtrr.txt> for more information. 1637 1638config MTRR_SANITIZER 1639 def_bool y 1640 prompt "MTRR cleanup support" 1641 depends on MTRR 1642 ---help--- 1643 Convert MTRR layout from continuous to discrete, so X drivers can 1644 add writeback entries. 1645 1646 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1647 The largest mtrr entry size for a continuous block can be set with 1648 mtrr_chunk_size. 1649 1650 If unsure, say Y. 1651 1652config MTRR_SANITIZER_ENABLE_DEFAULT 1653 int "MTRR cleanup enable value (0-1)" 1654 range 0 1 1655 default "0" 1656 depends on MTRR_SANITIZER 1657 ---help--- 1658 Enable mtrr cleanup default value 1659 1660config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1661 int "MTRR cleanup spare reg num (0-7)" 1662 range 0 7 1663 default "1" 1664 depends on MTRR_SANITIZER 1665 ---help--- 1666 mtrr cleanup spare entries default, it can be changed via 1667 mtrr_spare_reg_nr=N on the kernel command line. 1668 1669config X86_PAT 1670 def_bool y 1671 prompt "x86 PAT support" if EXPERT 1672 depends on MTRR 1673 ---help--- 1674 Use PAT attributes to setup page level cache control. 1675 1676 PATs are the modern equivalents of MTRRs and are much more 1677 flexible than MTRRs. 1678 1679 Say N here if you see bootup problems (boot crash, boot hang, 1680 spontaneous reboots) or a non-working video driver. 1681 1682 If unsure, say Y. 1683 1684config ARCH_USES_PG_UNCACHED 1685 def_bool y 1686 depends on X86_PAT 1687 1688config ARCH_RANDOM 1689 def_bool y 1690 prompt "x86 architectural random number generator" if EXPERT 1691 ---help--- 1692 Enable the x86 architectural RDRAND instruction 1693 (Intel Bull Mountain technology) to generate random numbers. 1694 If supported, this is a high bandwidth, cryptographically 1695 secure hardware random number generator. 1696 1697config X86_SMAP 1698 def_bool y 1699 prompt "Supervisor Mode Access Prevention" if EXPERT 1700 ---help--- 1701 Supervisor Mode Access Prevention (SMAP) is a security 1702 feature in newer Intel processors. There is a small 1703 performance cost if this enabled and turned on; there is 1704 also a small increase in the kernel size if this is enabled. 1705 1706 If unsure, say Y. 1707 1708config X86_INTEL_MPX 1709 prompt "Intel MPX (Memory Protection Extensions)" 1710 def_bool n 1711 depends on CPU_SUP_INTEL 1712 ---help--- 1713 MPX provides hardware features that can be used in 1714 conjunction with compiler-instrumented code to check 1715 memory references. It is designed to detect buffer 1716 overflow or underflow bugs. 1717 1718 This option enables running applications which are 1719 instrumented or otherwise use MPX. It does not use MPX 1720 itself inside the kernel or to protect the kernel 1721 against bad memory references. 1722 1723 Enabling this option will make the kernel larger: 1724 ~8k of kernel text and 36 bytes of data on a 64-bit 1725 defconfig. It adds a long to the 'mm_struct' which 1726 will increase the kernel memory overhead of each 1727 process and adds some branches to paths used during 1728 exec() and munmap(). 1729 1730 For details, see Documentation/x86/intel_mpx.txt 1731 1732 If unsure, say N. 1733 1734config X86_INTEL_MEMORY_PROTECTION_KEYS 1735 prompt "Intel Memory Protection Keys" 1736 def_bool y 1737 # Note: only available in 64-bit mode 1738 depends on CPU_SUP_INTEL && X86_64 1739 ---help--- 1740 Memory Protection Keys provides a mechanism for enforcing 1741 page-based protections, but without requiring modification of the 1742 page tables when an application changes protection domains. 1743 1744 For details, see Documentation/x86/protection-keys.txt 1745 1746 If unsure, say y. 1747 1748config EFI 1749 bool "EFI runtime service support" 1750 depends on ACPI 1751 select UCS2_STRING 1752 select EFI_RUNTIME_WRAPPERS 1753 ---help--- 1754 This enables the kernel to use EFI runtime services that are 1755 available (such as the EFI variable services). 1756 1757 This option is only useful on systems that have EFI firmware. 1758 In addition, you should use the latest ELILO loader available 1759 at <http://elilo.sourceforge.net> in order to take advantage 1760 of EFI runtime services. However, even with this option, the 1761 resultant kernel should continue to boot on existing non-EFI 1762 platforms. 1763 1764config EFI_STUB 1765 bool "EFI stub support" 1766 depends on EFI && !X86_USE_3DNOW 1767 select RELOCATABLE 1768 ---help--- 1769 This kernel feature allows a bzImage to be loaded directly 1770 by EFI firmware without the use of a bootloader. 1771 1772 See Documentation/efi-stub.txt for more information. 1773 1774config EFI_MIXED 1775 bool "EFI mixed-mode support" 1776 depends on EFI_STUB && X86_64 1777 ---help--- 1778 Enabling this feature allows a 64-bit kernel to be booted 1779 on a 32-bit firmware, provided that your CPU supports 64-bit 1780 mode. 1781 1782 Note that it is not possible to boot a mixed-mode enabled 1783 kernel via the EFI boot stub - a bootloader that supports 1784 the EFI handover protocol must be used. 1785 1786 If unsure, say N. 1787 1788config SECCOMP 1789 def_bool y 1790 prompt "Enable seccomp to safely compute untrusted bytecode" 1791 ---help--- 1792 This kernel feature is useful for number crunching applications 1793 that may need to compute untrusted bytecode during their 1794 execution. By using pipes or other transports made available to 1795 the process as file descriptors supporting the read/write 1796 syscalls, it's possible to isolate those applications in 1797 their own address space using seccomp. Once seccomp is 1798 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1799 and the task is only allowed to execute a few safe syscalls 1800 defined by each seccomp mode. 1801 1802 If unsure, say Y. Only embedded should say N here. 1803 1804source kernel/Kconfig.hz 1805 1806config KEXEC 1807 bool "kexec system call" 1808 select KEXEC_CORE 1809 ---help--- 1810 kexec is a system call that implements the ability to shutdown your 1811 current kernel, and to start another kernel. It is like a reboot 1812 but it is independent of the system firmware. And like a reboot 1813 you can start any kernel with it, not just Linux. 1814 1815 The name comes from the similarity to the exec system call. 1816 1817 It is an ongoing process to be certain the hardware in a machine 1818 is properly shutdown, so do not be surprised if this code does not 1819 initially work for you. As of this writing the exact hardware 1820 interface is strongly in flux, so no good recommendation can be 1821 made. 1822 1823config KEXEC_FILE 1824 bool "kexec file based system call" 1825 select KEXEC_CORE 1826 select BUILD_BIN2C 1827 depends on X86_64 1828 depends on CRYPTO=y 1829 depends on CRYPTO_SHA256=y 1830 ---help--- 1831 This is new version of kexec system call. This system call is 1832 file based and takes file descriptors as system call argument 1833 for kernel and initramfs as opposed to list of segments as 1834 accepted by previous system call. 1835 1836config KEXEC_VERIFY_SIG 1837 bool "Verify kernel signature during kexec_file_load() syscall" 1838 depends on KEXEC_FILE 1839 ---help--- 1840 This option makes kernel signature verification mandatory for 1841 the kexec_file_load() syscall. 1842 1843 In addition to that option, you need to enable signature 1844 verification for the corresponding kernel image type being 1845 loaded in order for this to work. 1846 1847config KEXEC_BZIMAGE_VERIFY_SIG 1848 bool "Enable bzImage signature verification support" 1849 depends on KEXEC_VERIFY_SIG 1850 depends on SIGNED_PE_FILE_VERIFICATION 1851 select SYSTEM_TRUSTED_KEYRING 1852 ---help--- 1853 Enable bzImage signature verification support. 1854 1855config CRASH_DUMP 1856 bool "kernel crash dumps" 1857 depends on X86_64 || (X86_32 && HIGHMEM) 1858 ---help--- 1859 Generate crash dump after being started by kexec. 1860 This should be normally only set in special crash dump kernels 1861 which are loaded in the main kernel with kexec-tools into 1862 a specially reserved region and then later executed after 1863 a crash by kdump/kexec. The crash dump kernel must be compiled 1864 to a memory address not used by the main kernel or BIOS using 1865 PHYSICAL_START, or it must be built as a relocatable image 1866 (CONFIG_RELOCATABLE=y). 1867 For more details see Documentation/kdump/kdump.txt 1868 1869config KEXEC_JUMP 1870 bool "kexec jump" 1871 depends on KEXEC && HIBERNATION 1872 ---help--- 1873 Jump between original kernel and kexeced kernel and invoke 1874 code in physical address mode via KEXEC 1875 1876config PHYSICAL_START 1877 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1878 default "0x1000000" 1879 ---help--- 1880 This gives the physical address where the kernel is loaded. 1881 1882 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1883 bzImage will decompress itself to above physical address and 1884 run from there. Otherwise, bzImage will run from the address where 1885 it has been loaded by the boot loader and will ignore above physical 1886 address. 1887 1888 In normal kdump cases one does not have to set/change this option 1889 as now bzImage can be compiled as a completely relocatable image 1890 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1891 address. This option is mainly useful for the folks who don't want 1892 to use a bzImage for capturing the crash dump and want to use a 1893 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1894 to be specifically compiled to run from a specific memory area 1895 (normally a reserved region) and this option comes handy. 1896 1897 So if you are using bzImage for capturing the crash dump, 1898 leave the value here unchanged to 0x1000000 and set 1899 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1900 for capturing the crash dump change this value to start of 1901 the reserved region. In other words, it can be set based on 1902 the "X" value as specified in the "crashkernel=YM@XM" 1903 command line boot parameter passed to the panic-ed 1904 kernel. Please take a look at Documentation/kdump/kdump.txt 1905 for more details about crash dumps. 1906 1907 Usage of bzImage for capturing the crash dump is recommended as 1908 one does not have to build two kernels. Same kernel can be used 1909 as production kernel and capture kernel. Above option should have 1910 gone away after relocatable bzImage support is introduced. But it 1911 is present because there are users out there who continue to use 1912 vmlinux for dump capture. This option should go away down the 1913 line. 1914 1915 Don't change this unless you know what you are doing. 1916 1917config RELOCATABLE 1918 bool "Build a relocatable kernel" 1919 default y 1920 ---help--- 1921 This builds a kernel image that retains relocation information 1922 so it can be loaded someplace besides the default 1MB. 1923 The relocations tend to make the kernel binary about 10% larger, 1924 but are discarded at runtime. 1925 1926 One use is for the kexec on panic case where the recovery kernel 1927 must live at a different physical address than the primary 1928 kernel. 1929 1930 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1931 it has been loaded at and the compile time physical address 1932 (CONFIG_PHYSICAL_START) is used as the minimum location. 1933 1934config RANDOMIZE_BASE 1935 bool "Randomize the address of the kernel image" 1936 depends on RELOCATABLE 1937 default n 1938 ---help--- 1939 Randomizes the physical and virtual address at which the 1940 kernel image is decompressed, as a security feature that 1941 deters exploit attempts relying on knowledge of the location 1942 of kernel internals. 1943 1944 Entropy is generated using the RDRAND instruction if it is 1945 supported. If RDTSC is supported, it is used as well. If 1946 neither RDRAND nor RDTSC are supported, then randomness is 1947 read from the i8254 timer. 1948 1949 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1950 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1951 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1952 minimum of 2MiB, only 10 bits of entropy is theoretically 1953 possible. At best, due to page table layouts, 64-bit can use 1954 9 bits of entropy and 32-bit uses 8 bits. 1955 1956 If unsure, say N. 1957 1958config RANDOMIZE_BASE_MAX_OFFSET 1959 hex "Maximum kASLR offset allowed" if EXPERT 1960 depends on RANDOMIZE_BASE 1961 range 0x0 0x20000000 if X86_32 1962 default "0x20000000" if X86_32 1963 range 0x0 0x40000000 if X86_64 1964 default "0x40000000" if X86_64 1965 ---help--- 1966 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1967 memory is used to determine the maximal offset in bytes that will 1968 be applied to the kernel when kernel Address Space Layout 1969 Randomization (kASLR) is active. This must be a multiple of 1970 PHYSICAL_ALIGN. 1971 1972 On 32-bit this is limited to 512MiB by page table layouts. The 1973 default is 512MiB. 1974 1975 On 64-bit this is limited by how the kernel fixmap page table is 1976 positioned, so this cannot be larger than 1GiB currently. Without 1977 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1978 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1979 modules area will shrink to compensate, up to the current maximum 1980 1GiB to 1GiB split. The default is 1GiB. 1981 1982 If unsure, leave at the default value. 1983 1984# Relocation on x86 needs some additional build support 1985config X86_NEED_RELOCS 1986 def_bool y 1987 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1988 1989config PHYSICAL_ALIGN 1990 hex "Alignment value to which kernel should be aligned" 1991 default "0x200000" 1992 range 0x2000 0x1000000 if X86_32 1993 range 0x200000 0x1000000 if X86_64 1994 ---help--- 1995 This value puts the alignment restrictions on physical address 1996 where kernel is loaded and run from. Kernel is compiled for an 1997 address which meets above alignment restriction. 1998 1999 If bootloader loads the kernel at a non-aligned address and 2000 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2001 address aligned to above value and run from there. 2002 2003 If bootloader loads the kernel at a non-aligned address and 2004 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2005 load address and decompress itself to the address it has been 2006 compiled for and run from there. The address for which kernel is 2007 compiled already meets above alignment restrictions. Hence the 2008 end result is that kernel runs from a physical address meeting 2009 above alignment restrictions. 2010 2011 On 32-bit this value must be a multiple of 0x2000. On 64-bit 2012 this value must be a multiple of 0x200000. 2013 2014 Don't change this unless you know what you are doing. 2015 2016config HOTPLUG_CPU 2017 bool "Support for hot-pluggable CPUs" 2018 depends on SMP 2019 ---help--- 2020 Say Y here to allow turning CPUs off and on. CPUs can be 2021 controlled through /sys/devices/system/cpu. 2022 ( Note: power management support will enable this option 2023 automatically on SMP systems. ) 2024 Say N if you want to disable CPU hotplug. 2025 2026config BOOTPARAM_HOTPLUG_CPU0 2027 bool "Set default setting of cpu0_hotpluggable" 2028 default n 2029 depends on HOTPLUG_CPU 2030 ---help--- 2031 Set whether default state of cpu0_hotpluggable is on or off. 2032 2033 Say Y here to enable CPU0 hotplug by default. If this switch 2034 is turned on, there is no need to give cpu0_hotplug kernel 2035 parameter and the CPU0 hotplug feature is enabled by default. 2036 2037 Please note: there are two known CPU0 dependencies if you want 2038 to enable the CPU0 hotplug feature either by this switch or by 2039 cpu0_hotplug kernel parameter. 2040 2041 First, resume from hibernate or suspend always starts from CPU0. 2042 So hibernate and suspend are prevented if CPU0 is offline. 2043 2044 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2045 offline if any interrupt can not migrate out of CPU0. There may 2046 be other CPU0 dependencies. 2047 2048 Please make sure the dependencies are under your control before 2049 you enable this feature. 2050 2051 Say N if you don't want to enable CPU0 hotplug feature by default. 2052 You still can enable the CPU0 hotplug feature at boot by kernel 2053 parameter cpu0_hotplug. 2054 2055config DEBUG_HOTPLUG_CPU0 2056 def_bool n 2057 prompt "Debug CPU0 hotplug" 2058 depends on HOTPLUG_CPU 2059 ---help--- 2060 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2061 soon as possible and boots up userspace with CPU0 offlined. User 2062 can online CPU0 back after boot time. 2063 2064 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2065 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2066 compilation or giving cpu0_hotplug kernel parameter at boot. 2067 2068 If unsure, say N. 2069 2070config COMPAT_VDSO 2071 def_bool n 2072 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2073 depends on X86_32 || IA32_EMULATION 2074 ---help--- 2075 Certain buggy versions of glibc will crash if they are 2076 presented with a 32-bit vDSO that is not mapped at the address 2077 indicated in its segment table. 2078 2079 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2080 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2081 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2082 the only released version with the bug, but OpenSUSE 9 2083 contains a buggy "glibc 2.3.2". 2084 2085 The symptom of the bug is that everything crashes on startup, saying: 2086 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2087 2088 Saying Y here changes the default value of the vdso32 boot 2089 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2090 This works around the glibc bug but hurts performance. 2091 2092 If unsure, say N: if you are compiling your own kernel, you 2093 are unlikely to be using a buggy version of glibc. 2094 2095choice 2096 prompt "vsyscall table for legacy applications" 2097 depends on X86_64 2098 default LEGACY_VSYSCALL_EMULATE 2099 help 2100 Legacy user code that does not know how to find the vDSO expects 2101 to be able to issue three syscalls by calling fixed addresses in 2102 kernel space. Since this location is not randomized with ASLR, 2103 it can be used to assist security vulnerability exploitation. 2104 2105 This setting can be changed at boot time via the kernel command 2106 line parameter vsyscall=[native|emulate|none]. 2107 2108 On a system with recent enough glibc (2.14 or newer) and no 2109 static binaries, you can say None without a performance penalty 2110 to improve security. 2111 2112 If unsure, select "Emulate". 2113 2114 config LEGACY_VSYSCALL_NATIVE 2115 bool "Native" 2116 help 2117 Actual executable code is located in the fixed vsyscall 2118 address mapping, implementing time() efficiently. Since 2119 this makes the mapping executable, it can be used during 2120 security vulnerability exploitation (traditionally as 2121 ROP gadgets). This configuration is not recommended. 2122 2123 config LEGACY_VSYSCALL_EMULATE 2124 bool "Emulate" 2125 help 2126 The kernel traps and emulates calls into the fixed 2127 vsyscall address mapping. This makes the mapping 2128 non-executable, but it still contains known contents, 2129 which could be used in certain rare security vulnerability 2130 exploits. This configuration is recommended when userspace 2131 still uses the vsyscall area. 2132 2133 config LEGACY_VSYSCALL_NONE 2134 bool "None" 2135 help 2136 There will be no vsyscall mapping at all. This will 2137 eliminate any risk of ASLR bypass due to the vsyscall 2138 fixed address mapping. Attempts to use the vsyscalls 2139 will be reported to dmesg, so that either old or 2140 malicious userspace programs can be identified. 2141 2142endchoice 2143 2144config CMDLINE_BOOL 2145 bool "Built-in kernel command line" 2146 ---help--- 2147 Allow for specifying boot arguments to the kernel at 2148 build time. On some systems (e.g. embedded ones), it is 2149 necessary or convenient to provide some or all of the 2150 kernel boot arguments with the kernel itself (that is, 2151 to not rely on the boot loader to provide them.) 2152 2153 To compile command line arguments into the kernel, 2154 set this option to 'Y', then fill in the 2155 boot arguments in CONFIG_CMDLINE. 2156 2157 Systems with fully functional boot loaders (i.e. non-embedded) 2158 should leave this option set to 'N'. 2159 2160config CMDLINE 2161 string "Built-in kernel command string" 2162 depends on CMDLINE_BOOL 2163 default "" 2164 ---help--- 2165 Enter arguments here that should be compiled into the kernel 2166 image and used at boot time. If the boot loader provides a 2167 command line at boot time, it is appended to this string to 2168 form the full kernel command line, when the system boots. 2169 2170 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2171 change this behavior. 2172 2173 In most cases, the command line (whether built-in or provided 2174 by the boot loader) should specify the device for the root 2175 file system. 2176 2177config CMDLINE_OVERRIDE 2178 bool "Built-in command line overrides boot loader arguments" 2179 depends on CMDLINE_BOOL 2180 ---help--- 2181 Set this option to 'Y' to have the kernel ignore the boot loader 2182 command line, and use ONLY the built-in command line. 2183 2184 This is used to work around broken boot loaders. This should 2185 be set to 'N' under normal conditions. 2186 2187config MODIFY_LDT_SYSCALL 2188 bool "Enable the LDT (local descriptor table)" if EXPERT 2189 default y 2190 ---help--- 2191 Linux can allow user programs to install a per-process x86 2192 Local Descriptor Table (LDT) using the modify_ldt(2) system 2193 call. This is required to run 16-bit or segmented code such as 2194 DOSEMU or some Wine programs. It is also used by some very old 2195 threading libraries. 2196 2197 Enabling this feature adds a small amount of overhead to 2198 context switches and increases the low-level kernel attack 2199 surface. Disabling it removes the modify_ldt(2) system call. 2200 2201 Saying 'N' here may make sense for embedded or server kernels. 2202 2203source "kernel/livepatch/Kconfig" 2204 2205endmenu 2206 2207config ARCH_ENABLE_MEMORY_HOTPLUG 2208 def_bool y 2209 depends on X86_64 || (X86_32 && HIGHMEM) 2210 2211config ARCH_ENABLE_MEMORY_HOTREMOVE 2212 def_bool y 2213 depends on MEMORY_HOTPLUG 2214 2215config USE_PERCPU_NUMA_NODE_ID 2216 def_bool y 2217 depends on NUMA 2218 2219config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2220 def_bool y 2221 depends on X86_64 || X86_PAE 2222 2223config ARCH_ENABLE_HUGEPAGE_MIGRATION 2224 def_bool y 2225 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2226 2227menu "Power management and ACPI options" 2228 2229config ARCH_HIBERNATION_HEADER 2230 def_bool y 2231 depends on X86_64 && HIBERNATION 2232 2233source "kernel/power/Kconfig" 2234 2235source "drivers/acpi/Kconfig" 2236 2237source "drivers/sfi/Kconfig" 2238 2239config X86_APM_BOOT 2240 def_bool y 2241 depends on APM 2242 2243menuconfig APM 2244 tristate "APM (Advanced Power Management) BIOS support" 2245 depends on X86_32 && PM_SLEEP 2246 ---help--- 2247 APM is a BIOS specification for saving power using several different 2248 techniques. This is mostly useful for battery powered laptops with 2249 APM compliant BIOSes. If you say Y here, the system time will be 2250 reset after a RESUME operation, the /proc/apm device will provide 2251 battery status information, and user-space programs will receive 2252 notification of APM "events" (e.g. battery status change). 2253 2254 If you select "Y" here, you can disable actual use of the APM 2255 BIOS by passing the "apm=off" option to the kernel at boot time. 2256 2257 Note that the APM support is almost completely disabled for 2258 machines with more than one CPU. 2259 2260 In order to use APM, you will need supporting software. For location 2261 and more information, read <file:Documentation/power/apm-acpi.txt> 2262 and the Battery Powered Linux mini-HOWTO, available from 2263 <http://www.tldp.org/docs.html#howto>. 2264 2265 This driver does not spin down disk drives (see the hdparm(8) 2266 manpage ("man 8 hdparm") for that), and it doesn't turn off 2267 VESA-compliant "green" monitors. 2268 2269 This driver does not support the TI 4000M TravelMate and the ACER 2270 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2271 desktop machines also don't have compliant BIOSes, and this driver 2272 may cause those machines to panic during the boot phase. 2273 2274 Generally, if you don't have a battery in your machine, there isn't 2275 much point in using this driver and you should say N. If you get 2276 random kernel OOPSes or reboots that don't seem to be related to 2277 anything, try disabling/enabling this option (or disabling/enabling 2278 APM in your BIOS). 2279 2280 Some other things you should try when experiencing seemingly random, 2281 "weird" problems: 2282 2283 1) make sure that you have enough swap space and that it is 2284 enabled. 2285 2) pass the "no-hlt" option to the kernel 2286 3) switch on floating point emulation in the kernel and pass 2287 the "no387" option to the kernel 2288 4) pass the "floppy=nodma" option to the kernel 2289 5) pass the "mem=4M" option to the kernel (thereby disabling 2290 all but the first 4 MB of RAM) 2291 6) make sure that the CPU is not over clocked. 2292 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2293 8) disable the cache from your BIOS settings 2294 9) install a fan for the video card or exchange video RAM 2295 10) install a better fan for the CPU 2296 11) exchange RAM chips 2297 12) exchange the motherboard. 2298 2299 To compile this driver as a module, choose M here: the 2300 module will be called apm. 2301 2302if APM 2303 2304config APM_IGNORE_USER_SUSPEND 2305 bool "Ignore USER SUSPEND" 2306 ---help--- 2307 This option will ignore USER SUSPEND requests. On machines with a 2308 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2309 series notebooks, it is necessary to say Y because of a BIOS bug. 2310 2311config APM_DO_ENABLE 2312 bool "Enable PM at boot time" 2313 ---help--- 2314 Enable APM features at boot time. From page 36 of the APM BIOS 2315 specification: "When disabled, the APM BIOS does not automatically 2316 power manage devices, enter the Standby State, enter the Suspend 2317 State, or take power saving steps in response to CPU Idle calls." 2318 This driver will make CPU Idle calls when Linux is idle (unless this 2319 feature is turned off -- see "Do CPU IDLE calls", below). This 2320 should always save battery power, but more complicated APM features 2321 will be dependent on your BIOS implementation. You may need to turn 2322 this option off if your computer hangs at boot time when using APM 2323 support, or if it beeps continuously instead of suspending. Turn 2324 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2325 T400CDT. This is off by default since most machines do fine without 2326 this feature. 2327 2328config APM_CPU_IDLE 2329 depends on CPU_IDLE 2330 bool "Make CPU Idle calls when idle" 2331 ---help--- 2332 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2333 On some machines, this can activate improved power savings, such as 2334 a slowed CPU clock rate, when the machine is idle. These idle calls 2335 are made after the idle loop has run for some length of time (e.g., 2336 333 mS). On some machines, this will cause a hang at boot time or 2337 whenever the CPU becomes idle. (On machines with more than one CPU, 2338 this option does nothing.) 2339 2340config APM_DISPLAY_BLANK 2341 bool "Enable console blanking using APM" 2342 ---help--- 2343 Enable console blanking using the APM. Some laptops can use this to 2344 turn off the LCD backlight when the screen blanker of the Linux 2345 virtual console blanks the screen. Note that this is only used by 2346 the virtual console screen blanker, and won't turn off the backlight 2347 when using the X Window system. This also doesn't have anything to 2348 do with your VESA-compliant power-saving monitor. Further, this 2349 option doesn't work for all laptops -- it might not turn off your 2350 backlight at all, or it might print a lot of errors to the console, 2351 especially if you are using gpm. 2352 2353config APM_ALLOW_INTS 2354 bool "Allow interrupts during APM BIOS calls" 2355 ---help--- 2356 Normally we disable external interrupts while we are making calls to 2357 the APM BIOS as a measure to lessen the effects of a badly behaving 2358 BIOS implementation. The BIOS should reenable interrupts if it 2359 needs to. Unfortunately, some BIOSes do not -- especially those in 2360 many of the newer IBM Thinkpads. If you experience hangs when you 2361 suspend, try setting this to Y. Otherwise, say N. 2362 2363endif # APM 2364 2365source "drivers/cpufreq/Kconfig" 2366 2367source "drivers/cpuidle/Kconfig" 2368 2369source "drivers/idle/Kconfig" 2370 2371endmenu 2372 2373 2374menu "Bus options (PCI etc.)" 2375 2376config PCI 2377 bool "PCI support" 2378 default y 2379 ---help--- 2380 Find out whether you have a PCI motherboard. PCI is the name of a 2381 bus system, i.e. the way the CPU talks to the other stuff inside 2382 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2383 VESA. If you have PCI, say Y, otherwise N. 2384 2385choice 2386 prompt "PCI access mode" 2387 depends on X86_32 && PCI 2388 default PCI_GOANY 2389 ---help--- 2390 On PCI systems, the BIOS can be used to detect the PCI devices and 2391 determine their configuration. However, some old PCI motherboards 2392 have BIOS bugs and may crash if this is done. Also, some embedded 2393 PCI-based systems don't have any BIOS at all. Linux can also try to 2394 detect the PCI hardware directly without using the BIOS. 2395 2396 With this option, you can specify how Linux should detect the 2397 PCI devices. If you choose "BIOS", the BIOS will be used, 2398 if you choose "Direct", the BIOS won't be used, and if you 2399 choose "MMConfig", then PCI Express MMCONFIG will be used. 2400 If you choose "Any", the kernel will try MMCONFIG, then the 2401 direct access method and falls back to the BIOS if that doesn't 2402 work. If unsure, go with the default, which is "Any". 2403 2404config PCI_GOBIOS 2405 bool "BIOS" 2406 2407config PCI_GOMMCONFIG 2408 bool "MMConfig" 2409 2410config PCI_GODIRECT 2411 bool "Direct" 2412 2413config PCI_GOOLPC 2414 bool "OLPC XO-1" 2415 depends on OLPC 2416 2417config PCI_GOANY 2418 bool "Any" 2419 2420endchoice 2421 2422config PCI_BIOS 2423 def_bool y 2424 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2425 2426# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2427config PCI_DIRECT 2428 def_bool y 2429 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2430 2431config PCI_MMCONFIG 2432 def_bool y 2433 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2434 2435config PCI_OLPC 2436 def_bool y 2437 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2438 2439config PCI_XEN 2440 def_bool y 2441 depends on PCI && XEN 2442 select SWIOTLB_XEN 2443 2444config PCI_DOMAINS 2445 def_bool y 2446 depends on PCI 2447 2448config PCI_MMCONFIG 2449 bool "Support mmconfig PCI config space access" 2450 depends on X86_64 && PCI && ACPI 2451 2452config PCI_CNB20LE_QUIRK 2453 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2454 depends on PCI 2455 help 2456 Read the PCI windows out of the CNB20LE host bridge. This allows 2457 PCI hotplug to work on systems with the CNB20LE chipset which do 2458 not have ACPI. 2459 2460 There's no public spec for this chipset, and this functionality 2461 is known to be incomplete. 2462 2463 You should say N unless you know you need this. 2464 2465source "drivers/pci/Kconfig" 2466 2467# x86_64 have no ISA slots, but can have ISA-style DMA. 2468config ISA_DMA_API 2469 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2470 default y 2471 help 2472 Enables ISA-style DMA support for devices requiring such controllers. 2473 If unsure, say Y. 2474 2475if X86_32 2476 2477config ISA 2478 bool "ISA support" 2479 ---help--- 2480 Find out whether you have ISA slots on your motherboard. ISA is the 2481 name of a bus system, i.e. the way the CPU talks to the other stuff 2482 inside your box. Other bus systems are PCI, EISA, MicroChannel 2483 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2484 newer boards don't support it. If you have ISA, say Y, otherwise N. 2485 2486config EISA 2487 bool "EISA support" 2488 depends on ISA 2489 ---help--- 2490 The Extended Industry Standard Architecture (EISA) bus was 2491 developed as an open alternative to the IBM MicroChannel bus. 2492 2493 The EISA bus provided some of the features of the IBM MicroChannel 2494 bus while maintaining backward compatibility with cards made for 2495 the older ISA bus. The EISA bus saw limited use between 1988 and 2496 1995 when it was made obsolete by the PCI bus. 2497 2498 Say Y here if you are building a kernel for an EISA-based machine. 2499 2500 Otherwise, say N. 2501 2502source "drivers/eisa/Kconfig" 2503 2504config SCx200 2505 tristate "NatSemi SCx200 support" 2506 ---help--- 2507 This provides basic support for National Semiconductor's 2508 (now AMD's) Geode processors. The driver probes for the 2509 PCI-IDs of several on-chip devices, so its a good dependency 2510 for other scx200_* drivers. 2511 2512 If compiled as a module, the driver is named scx200. 2513 2514config SCx200HR_TIMER 2515 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2516 depends on SCx200 2517 default y 2518 ---help--- 2519 This driver provides a clocksource built upon the on-chip 2520 27MHz high-resolution timer. Its also a workaround for 2521 NSC Geode SC-1100's buggy TSC, which loses time when the 2522 processor goes idle (as is done by the scheduler). The 2523 other workaround is idle=poll boot option. 2524 2525config OLPC 2526 bool "One Laptop Per Child support" 2527 depends on !X86_PAE 2528 select GPIOLIB 2529 select OF 2530 select OF_PROMTREE 2531 select IRQ_DOMAIN 2532 ---help--- 2533 Add support for detecting the unique features of the OLPC 2534 XO hardware. 2535 2536config OLPC_XO1_PM 2537 bool "OLPC XO-1 Power Management" 2538 depends on OLPC && MFD_CS5535 && PM_SLEEP 2539 select MFD_CORE 2540 ---help--- 2541 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2542 2543config OLPC_XO1_RTC 2544 bool "OLPC XO-1 Real Time Clock" 2545 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2546 ---help--- 2547 Add support for the XO-1 real time clock, which can be used as a 2548 programmable wakeup source. 2549 2550config OLPC_XO1_SCI 2551 bool "OLPC XO-1 SCI extras" 2552 depends on OLPC && OLPC_XO1_PM 2553 depends on INPUT=y 2554 select POWER_SUPPLY 2555 select GPIO_CS5535 2556 select MFD_CORE 2557 ---help--- 2558 Add support for SCI-based features of the OLPC XO-1 laptop: 2559 - EC-driven system wakeups 2560 - Power button 2561 - Ebook switch 2562 - Lid switch 2563 - AC adapter status updates 2564 - Battery status updates 2565 2566config OLPC_XO15_SCI 2567 bool "OLPC XO-1.5 SCI extras" 2568 depends on OLPC && ACPI 2569 select POWER_SUPPLY 2570 ---help--- 2571 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2572 - EC-driven system wakeups 2573 - AC adapter status updates 2574 - Battery status updates 2575 2576config ALIX 2577 bool "PCEngines ALIX System Support (LED setup)" 2578 select GPIOLIB 2579 ---help--- 2580 This option enables system support for the PCEngines ALIX. 2581 At present this just sets up LEDs for GPIO control on 2582 ALIX2/3/6 boards. However, other system specific setup should 2583 get added here. 2584 2585 Note: You must still enable the drivers for GPIO and LED support 2586 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2587 2588 Note: You have to set alix.force=1 for boards with Award BIOS. 2589 2590config NET5501 2591 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2592 select GPIOLIB 2593 ---help--- 2594 This option enables system support for the Soekris Engineering net5501. 2595 2596config GEOS 2597 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2598 select GPIOLIB 2599 depends on DMI 2600 ---help--- 2601 This option enables system support for the Traverse Technologies GEOS. 2602 2603config TS5500 2604 bool "Technologic Systems TS-5500 platform support" 2605 depends on MELAN 2606 select CHECK_SIGNATURE 2607 select NEW_LEDS 2608 select LEDS_CLASS 2609 ---help--- 2610 This option enables system support for the Technologic Systems TS-5500. 2611 2612endif # X86_32 2613 2614config AMD_NB 2615 def_bool y 2616 depends on CPU_SUP_AMD && PCI 2617 2618source "drivers/pcmcia/Kconfig" 2619 2620config RAPIDIO 2621 tristate "RapidIO support" 2622 depends on PCI 2623 default n 2624 help 2625 If enabled this option will include drivers and the core 2626 infrastructure code to support RapidIO interconnect devices. 2627 2628source "drivers/rapidio/Kconfig" 2629 2630config X86_SYSFB 2631 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2632 help 2633 Firmwares often provide initial graphics framebuffers so the BIOS, 2634 bootloader or kernel can show basic video-output during boot for 2635 user-guidance and debugging. Historically, x86 used the VESA BIOS 2636 Extensions and EFI-framebuffers for this, which are mostly limited 2637 to x86. 2638 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2639 framebuffers so the new generic system-framebuffer drivers can be 2640 used on x86. If the framebuffer is not compatible with the generic 2641 modes, it is adverticed as fallback platform framebuffer so legacy 2642 drivers like efifb, vesafb and uvesafb can pick it up. 2643 If this option is not selected, all system framebuffers are always 2644 marked as fallback platform framebuffers as usual. 2645 2646 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2647 not be able to pick up generic system framebuffers if this option 2648 is selected. You are highly encouraged to enable simplefb as 2649 replacement if you select this option. simplefb can correctly deal 2650 with generic system framebuffers. But you should still keep vesafb 2651 and others enabled as fallback if a system framebuffer is 2652 incompatible with simplefb. 2653 2654 If unsure, say Y. 2655 2656endmenu 2657 2658 2659menu "Executable file formats / Emulations" 2660 2661source "fs/Kconfig.binfmt" 2662 2663config IA32_EMULATION 2664 bool "IA32 Emulation" 2665 depends on X86_64 2666 select BINFMT_ELF 2667 select COMPAT_BINFMT_ELF 2668 select ARCH_WANT_OLD_COMPAT_IPC 2669 ---help--- 2670 Include code to run legacy 32-bit programs under a 2671 64-bit kernel. You should likely turn this on, unless you're 2672 100% sure that you don't have any 32-bit programs left. 2673 2674config IA32_AOUT 2675 tristate "IA32 a.out support" 2676 depends on IA32_EMULATION 2677 ---help--- 2678 Support old a.out binaries in the 32bit emulation. 2679 2680config X86_X32 2681 bool "x32 ABI for 64-bit mode" 2682 depends on X86_64 2683 ---help--- 2684 Include code to run binaries for the x32 native 32-bit ABI 2685 for 64-bit processors. An x32 process gets access to the 2686 full 64-bit register file and wide data path while leaving 2687 pointers at 32 bits for smaller memory footprint. 2688 2689 You will need a recent binutils (2.22 or later) with 2690 elf32_x86_64 support enabled to compile a kernel with this 2691 option set. 2692 2693config COMPAT 2694 def_bool y 2695 depends on IA32_EMULATION || X86_X32 2696 2697if COMPAT 2698config COMPAT_FOR_U64_ALIGNMENT 2699 def_bool y 2700 2701config SYSVIPC_COMPAT 2702 def_bool y 2703 depends on SYSVIPC 2704 2705config KEYS_COMPAT 2706 def_bool y 2707 depends on KEYS 2708endif 2709 2710endmenu 2711 2712 2713config HAVE_ATOMIC_IOMAP 2714 def_bool y 2715 depends on X86_32 2716 2717config X86_DEV_DMA_OPS 2718 bool 2719 depends on X86_64 || STA2X11 2720 2721config X86_DMA_REMAP 2722 bool 2723 depends on STA2X11 2724 2725config PMC_ATOM 2726 def_bool y 2727 depends on PCI 2728 2729config VMD 2730 depends on PCI_MSI 2731 tristate "Volume Management Device Driver" 2732 default N 2733 ---help--- 2734 Adds support for the Intel Volume Management Device (VMD). VMD is a 2735 secondary PCI host bridge that allows PCI Express root ports, 2736 and devices attached to them, to be removed from the default 2737 PCI domain and placed within the VMD domain. This provides 2738 more bus resources than are otherwise possible with a 2739 single domain. If you know your system provides one of these and 2740 has devices attached to it, say Y; if you are not sure, say N. 2741 2742source "net/Kconfig" 2743 2744source "drivers/Kconfig" 2745 2746source "drivers/firmware/Kconfig" 2747 2748source "fs/Kconfig" 2749 2750source "arch/x86/Kconfig.debug" 2751 2752source "security/Kconfig" 2753 2754source "crypto/Kconfig" 2755 2756source "arch/x86/kvm/Kconfig" 2757 2758source "lib/Kconfig" 2759