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 # Options that are inherently 32-bit kernel only: 13 select ARCH_WANT_IPC_PARSE_VERSION 14 select CLKSRC_I8253 15 select CLONE_BACKWARDS 16 select HAVE_AOUT 17 select HAVE_GENERIC_DMA_COHERENT 18 select MODULES_USE_ELF_REL 19 select OLD_SIGACTION 20 21config X86_64 22 def_bool y 23 depends on 64BIT 24 # Options that are inherently 64-bit kernel only: 25 select ARCH_HAS_GIGANTIC_PAGE 26 select ARCH_SUPPORTS_INT128 27 select ARCH_USE_CMPXCHG_LOCKREF 28 select HAVE_ARCH_SOFT_DIRTY 29 select MODULES_USE_ELF_RELA 30 select X86_DEV_DMA_OPS 31 32# 33# Arch settings 34# 35# ( Note that options that are marked 'if X86_64' could in principle be 36# ported to 32-bit as well. ) 37# 38config X86 39 def_bool y 40 # 41 # Note: keep this list sorted alphabetically 42 # 43 select ACPI_LEGACY_TABLES_LOOKUP if ACPI 44 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 45 select ANON_INODES 46 select ARCH_CLOCKSOURCE_DATA 47 select ARCH_DISCARD_MEMBLOCK 48 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 49 select ARCH_HAS_DEVMEM_IS_ALLOWED 50 select ARCH_HAS_ELF_RANDOMIZE 51 select ARCH_HAS_FAST_MULTIPLIER 52 select ARCH_HAS_GCOV_PROFILE_ALL 53 select ARCH_HAS_KCOV if X86_64 54 select ARCH_HAS_MMIO_FLUSH 55 select ARCH_HAS_PMEM_API if X86_64 56 select ARCH_HAS_SG_CHAIN 57 select ARCH_HAS_UBSAN_SANITIZE_ALL 58 select ARCH_HAVE_NMI_SAFE_CMPXCHG 59 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 60 select ARCH_MIGHT_HAVE_PC_PARPORT 61 select ARCH_MIGHT_HAVE_PC_SERIO 62 select ARCH_SUPPORTS_ATOMIC_RMW 63 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 64 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 65 select ARCH_USE_BUILTIN_BSWAP 66 select ARCH_USE_QUEUED_RWLOCKS 67 select ARCH_USE_QUEUED_SPINLOCKS 68 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 69 select ARCH_WANT_FRAME_POINTERS 70 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 71 select BUILDTIME_EXTABLE_SORT 72 select CLKEVT_I8253 73 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 74 select CLOCKSOURCE_WATCHDOG 75 select DCACHE_WORD_ACCESS 76 select EDAC_ATOMIC_SCRUB 77 select EDAC_SUPPORT 78 select GENERIC_CLOCKEVENTS 79 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 80 select GENERIC_CLOCKEVENTS_MIN_ADJUST 81 select GENERIC_CMOS_UPDATE 82 select GENERIC_CPU_AUTOPROBE 83 select GENERIC_EARLY_IOREMAP 84 select GENERIC_FIND_FIRST_BIT 85 select GENERIC_IOMAP 86 select GENERIC_IRQ_PROBE 87 select GENERIC_IRQ_SHOW 88 select GENERIC_PENDING_IRQ if SMP 89 select GENERIC_SMP_IDLE_THREAD 90 select GENERIC_STRNCPY_FROM_USER 91 select GENERIC_STRNLEN_USER 92 select GENERIC_TIME_VSYSCALL 93 select HAVE_ACPI_APEI if ACPI 94 select HAVE_ACPI_APEI_NMI if ACPI 95 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 96 select HAVE_ARCH_AUDITSYSCALL 97 select HAVE_ARCH_HARDENED_USERCOPY 98 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 99 select HAVE_ARCH_JUMP_LABEL 100 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 101 select HAVE_ARCH_KGDB 102 select HAVE_ARCH_KMEMCHECK 103 select HAVE_ARCH_MMAP_RND_BITS if MMU 104 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 105 select HAVE_ARCH_SECCOMP_FILTER 106 select HAVE_ARCH_TRACEHOOK 107 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 108 select HAVE_ARCH_VMAP_STACK if X86_64 109 select HAVE_ARCH_WITHIN_STACK_FRAMES 110 select HAVE_CC_STACKPROTECTOR 111 select HAVE_CMPXCHG_DOUBLE 112 select HAVE_CMPXCHG_LOCAL 113 select HAVE_CONTEXT_TRACKING if X86_64 114 select HAVE_COPY_THREAD_TLS 115 select HAVE_C_RECORDMCOUNT 116 select HAVE_DEBUG_KMEMLEAK 117 select HAVE_DEBUG_STACKOVERFLOW 118 select HAVE_DMA_API_DEBUG 119 select HAVE_DMA_CONTIGUOUS 120 select HAVE_DYNAMIC_FTRACE 121 select HAVE_DYNAMIC_FTRACE_WITH_REGS 122 select HAVE_EBPF_JIT if X86_64 123 select HAVE_EFFICIENT_UNALIGNED_ACCESS 124 select HAVE_EXIT_THREAD 125 select HAVE_FENTRY if X86_64 126 select HAVE_FTRACE_MCOUNT_RECORD 127 select HAVE_FUNCTION_GRAPH_TRACER 128 select HAVE_FUNCTION_TRACER 129 select HAVE_GCC_PLUGINS 130 select HAVE_HW_BREAKPOINT 131 select HAVE_IDE 132 select HAVE_IOREMAP_PROT 133 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 134 select HAVE_IRQ_TIME_ACCOUNTING 135 select HAVE_KERNEL_BZIP2 136 select HAVE_KERNEL_GZIP 137 select HAVE_KERNEL_LZ4 138 select HAVE_KERNEL_LZMA 139 select HAVE_KERNEL_LZO 140 select HAVE_KERNEL_XZ 141 select HAVE_KPROBES 142 select HAVE_KPROBES_ON_FTRACE 143 select HAVE_KRETPROBES 144 select HAVE_KVM 145 select HAVE_LIVEPATCH if X86_64 146 select HAVE_MEMBLOCK 147 select HAVE_MEMBLOCK_NODE_MAP 148 select HAVE_MIXED_BREAKPOINTS_REGS 149 select HAVE_NMI 150 select HAVE_OPROFILE 151 select HAVE_OPTPROBES 152 select HAVE_PCSPKR_PLATFORM 153 select HAVE_PERF_EVENTS 154 select HAVE_PERF_EVENTS_NMI 155 select HAVE_PERF_REGS 156 select HAVE_PERF_USER_STACK_DUMP 157 select HAVE_REGS_AND_STACK_ACCESS_API 158 select HAVE_STACK_VALIDATION if X86_64 159 select HAVE_SYSCALL_TRACEPOINTS 160 select HAVE_UNSTABLE_SCHED_CLOCK 161 select HAVE_USER_RETURN_NOTIFIER 162 select IRQ_FORCED_THREADING 163 select PERF_EVENTS 164 select RTC_LIB 165 select RTC_MC146818_LIB 166 select SPARSE_IRQ 167 select SRCU 168 select SYSCTL_EXCEPTION_TRACE 169 select THREAD_INFO_IN_TASK 170 select USER_STACKTRACE_SUPPORT 171 select VIRT_TO_BUS 172 select X86_FEATURE_NAMES if PROC_FS 173 174config INSTRUCTION_DECODER 175 def_bool y 176 depends on KPROBES || PERF_EVENTS || UPROBES 177 178config OUTPUT_FORMAT 179 string 180 default "elf32-i386" if X86_32 181 default "elf64-x86-64" if X86_64 182 183config ARCH_DEFCONFIG 184 string 185 default "arch/x86/configs/i386_defconfig" if X86_32 186 default "arch/x86/configs/x86_64_defconfig" if X86_64 187 188config LOCKDEP_SUPPORT 189 def_bool y 190 191config STACKTRACE_SUPPORT 192 def_bool y 193 194config MMU 195 def_bool y 196 197config ARCH_MMAP_RND_BITS_MIN 198 default 28 if 64BIT 199 default 8 200 201config ARCH_MMAP_RND_BITS_MAX 202 default 32 if 64BIT 203 default 16 204 205config ARCH_MMAP_RND_COMPAT_BITS_MIN 206 default 8 207 208config ARCH_MMAP_RND_COMPAT_BITS_MAX 209 default 16 210 211config SBUS 212 bool 213 214config NEED_DMA_MAP_STATE 215 def_bool y 216 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 217 218config NEED_SG_DMA_LENGTH 219 def_bool y 220 221config GENERIC_ISA_DMA 222 def_bool y 223 depends on ISA_DMA_API 224 225config GENERIC_BUG 226 def_bool y 227 depends on BUG 228 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 229 230config GENERIC_BUG_RELATIVE_POINTERS 231 bool 232 233config GENERIC_HWEIGHT 234 def_bool y 235 236config ARCH_MAY_HAVE_PC_FDC 237 def_bool y 238 depends on ISA_DMA_API 239 240config RWSEM_XCHGADD_ALGORITHM 241 def_bool y 242 243config GENERIC_CALIBRATE_DELAY 244 def_bool y 245 246config ARCH_HAS_CPU_RELAX 247 def_bool y 248 249config ARCH_HAS_CACHE_LINE_SIZE 250 def_bool y 251 252config HAVE_SETUP_PER_CPU_AREA 253 def_bool y 254 255config NEED_PER_CPU_EMBED_FIRST_CHUNK 256 def_bool y 257 258config NEED_PER_CPU_PAGE_FIRST_CHUNK 259 def_bool y 260 261config ARCH_HIBERNATION_POSSIBLE 262 def_bool y 263 264config ARCH_SUSPEND_POSSIBLE 265 def_bool y 266 267config ARCH_WANT_HUGE_PMD_SHARE 268 def_bool y 269 270config ARCH_WANT_GENERAL_HUGETLB 271 def_bool y 272 273config ZONE_DMA32 274 def_bool y if X86_64 275 276config AUDIT_ARCH 277 def_bool y if X86_64 278 279config ARCH_SUPPORTS_OPTIMIZED_INLINING 280 def_bool y 281 282config ARCH_SUPPORTS_DEBUG_PAGEALLOC 283 def_bool y 284 285config KASAN_SHADOW_OFFSET 286 hex 287 depends on KASAN 288 default 0xdffffc0000000000 289 290config HAVE_INTEL_TXT 291 def_bool y 292 depends on INTEL_IOMMU && ACPI 293 294config X86_32_SMP 295 def_bool y 296 depends on X86_32 && SMP 297 298config X86_64_SMP 299 def_bool y 300 depends on X86_64 && SMP 301 302config X86_32_LAZY_GS 303 def_bool y 304 depends on X86_32 && !CC_STACKPROTECTOR 305 306config ARCH_SUPPORTS_UPROBES 307 def_bool y 308 309config FIX_EARLYCON_MEM 310 def_bool y 311 312config DEBUG_RODATA 313 def_bool y 314 315config PGTABLE_LEVELS 316 int 317 default 4 if X86_64 318 default 3 if X86_PAE 319 default 2 320 321source "init/Kconfig" 322source "kernel/Kconfig.freezer" 323 324menu "Processor type and features" 325 326config ZONE_DMA 327 bool "DMA memory allocation support" if EXPERT 328 default y 329 help 330 DMA memory allocation support allows devices with less than 32-bit 331 addressing to allocate within the first 16MB of address space. 332 Disable if no such devices will be used. 333 334 If unsure, say Y. 335 336config SMP 337 bool "Symmetric multi-processing support" 338 ---help--- 339 This enables support for systems with more than one CPU. If you have 340 a system with only one CPU, say N. If you have a system with more 341 than one CPU, say Y. 342 343 If you say N here, the kernel will run on uni- and multiprocessor 344 machines, but will use only one CPU of a multiprocessor machine. If 345 you say Y here, the kernel will run on many, but not all, 346 uniprocessor machines. On a uniprocessor machine, the kernel 347 will run faster if you say N here. 348 349 Note that if you say Y here and choose architecture "586" or 350 "Pentium" under "Processor family", the kernel will not work on 486 351 architectures. Similarly, multiprocessor kernels for the "PPro" 352 architecture may not work on all Pentium based boards. 353 354 People using multiprocessor machines who say Y here should also say 355 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 356 Management" code will be disabled if you say Y here. 357 358 See also <file:Documentation/x86/i386/IO-APIC.txt>, 359 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 360 <http://www.tldp.org/docs.html#howto>. 361 362 If you don't know what to do here, say N. 363 364config X86_FEATURE_NAMES 365 bool "Processor feature human-readable names" if EMBEDDED 366 default y 367 ---help--- 368 This option compiles in a table of x86 feature bits and corresponding 369 names. This is required to support /proc/cpuinfo and a few kernel 370 messages. You can disable this to save space, at the expense of 371 making those few kernel messages show numeric feature bits instead. 372 373 If in doubt, say Y. 374 375config X86_FAST_FEATURE_TESTS 376 bool "Fast CPU feature tests" if EMBEDDED 377 default y 378 ---help--- 379 Some fast-paths in the kernel depend on the capabilities of the CPU. 380 Say Y here for the kernel to patch in the appropriate code at runtime 381 based on the capabilities of the CPU. The infrastructure for patching 382 code at runtime takes up some additional space; space-constrained 383 embedded systems may wish to say N here to produce smaller, slightly 384 slower code. 385 386config X86_X2APIC 387 bool "Support x2apic" 388 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 389 ---help--- 390 This enables x2apic support on CPUs that have this feature. 391 392 This allows 32-bit apic IDs (so it can support very large systems), 393 and accesses the local apic via MSRs not via mmio. 394 395 If you don't know what to do here, say N. 396 397config X86_MPPARSE 398 bool "Enable MPS table" if ACPI || SFI 399 default y 400 depends on X86_LOCAL_APIC 401 ---help--- 402 For old smp systems that do not have proper acpi support. Newer systems 403 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 404 405config X86_BIGSMP 406 bool "Support for big SMP systems with more than 8 CPUs" 407 depends on X86_32 && SMP 408 ---help--- 409 This option is needed for the systems that have more than 8 CPUs 410 411config GOLDFISH 412 def_bool y 413 depends on X86_GOLDFISH 414 415if X86_32 416config X86_EXTENDED_PLATFORM 417 bool "Support for extended (non-PC) x86 platforms" 418 default y 419 ---help--- 420 If you disable this option then the kernel will only support 421 standard PC platforms. (which covers the vast majority of 422 systems out there.) 423 424 If you enable this option then you'll be able to select support 425 for the following (non-PC) 32 bit x86 platforms: 426 Goldfish (Android emulator) 427 AMD Elan 428 RDC R-321x SoC 429 SGI 320/540 (Visual Workstation) 430 STA2X11-based (e.g. Northville) 431 Moorestown MID devices 432 433 If you have one of these systems, or if you want to build a 434 generic distribution kernel, say Y here - otherwise say N. 435endif 436 437if X86_64 438config X86_EXTENDED_PLATFORM 439 bool "Support for extended (non-PC) x86 platforms" 440 default y 441 ---help--- 442 If you disable this option then the kernel will only support 443 standard PC platforms. (which covers the vast majority of 444 systems out there.) 445 446 If you enable this option then you'll be able to select support 447 for the following (non-PC) 64 bit x86 platforms: 448 Numascale NumaChip 449 ScaleMP vSMP 450 SGI Ultraviolet 451 452 If you have one of these systems, or if you want to build a 453 generic distribution kernel, say Y here - otherwise say N. 454endif 455# This is an alphabetically sorted list of 64 bit extended platforms 456# Please maintain the alphabetic order if and when there are additions 457config X86_NUMACHIP 458 bool "Numascale NumaChip" 459 depends on X86_64 460 depends on X86_EXTENDED_PLATFORM 461 depends on NUMA 462 depends on SMP 463 depends on X86_X2APIC 464 depends on PCI_MMCONFIG 465 ---help--- 466 Adds support for Numascale NumaChip large-SMP systems. Needed to 467 enable more than ~168 cores. 468 If you don't have one of these, you should say N here. 469 470config X86_VSMP 471 bool "ScaleMP vSMP" 472 select HYPERVISOR_GUEST 473 select PARAVIRT 474 depends on X86_64 && PCI 475 depends on X86_EXTENDED_PLATFORM 476 depends on SMP 477 ---help--- 478 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 479 supposed to run on these EM64T-based machines. Only choose this option 480 if you have one of these machines. 481 482config X86_UV 483 bool "SGI Ultraviolet" 484 depends on X86_64 485 depends on X86_EXTENDED_PLATFORM 486 depends on NUMA 487 depends on EFI 488 depends on X86_X2APIC 489 depends on PCI 490 ---help--- 491 This option is needed in order to support SGI Ultraviolet systems. 492 If you don't have one of these, you should say N here. 493 494# Following is an alphabetically sorted list of 32 bit extended platforms 495# Please maintain the alphabetic order if and when there are additions 496 497config X86_GOLDFISH 498 bool "Goldfish (Virtual Platform)" 499 depends on X86_EXTENDED_PLATFORM 500 ---help--- 501 Enable support for the Goldfish virtual platform used primarily 502 for Android development. Unless you are building for the Android 503 Goldfish emulator say N here. 504 505config X86_INTEL_CE 506 bool "CE4100 TV platform" 507 depends on PCI 508 depends on PCI_GODIRECT 509 depends on X86_IO_APIC 510 depends on X86_32 511 depends on X86_EXTENDED_PLATFORM 512 select X86_REBOOTFIXUPS 513 select OF 514 select OF_EARLY_FLATTREE 515 ---help--- 516 Select for the Intel CE media processor (CE4100) SOC. 517 This option compiles in support for the CE4100 SOC for settop 518 boxes and media devices. 519 520config X86_INTEL_MID 521 bool "Intel MID platform support" 522 depends on X86_EXTENDED_PLATFORM 523 depends on X86_PLATFORM_DEVICES 524 depends on PCI 525 depends on X86_64 || (PCI_GOANY && X86_32) 526 depends on X86_IO_APIC 527 select SFI 528 select I2C 529 select DW_APB_TIMER 530 select APB_TIMER 531 select INTEL_SCU_IPC 532 select MFD_INTEL_MSIC 533 ---help--- 534 Select to build a kernel capable of supporting Intel MID (Mobile 535 Internet Device) platform systems which do not have the PCI legacy 536 interfaces. If you are building for a PC class system say N here. 537 538 Intel MID platforms are based on an Intel processor and chipset which 539 consume less power than most of the x86 derivatives. 540 541config X86_INTEL_QUARK 542 bool "Intel Quark platform support" 543 depends on X86_32 544 depends on X86_EXTENDED_PLATFORM 545 depends on X86_PLATFORM_DEVICES 546 depends on X86_TSC 547 depends on PCI 548 depends on PCI_GOANY 549 depends on X86_IO_APIC 550 select IOSF_MBI 551 select INTEL_IMR 552 select COMMON_CLK 553 ---help--- 554 Select to include support for Quark X1000 SoC. 555 Say Y here if you have a Quark based system such as the Arduino 556 compatible Intel Galileo. 557 558config MLX_PLATFORM 559 tristate "Mellanox Technologies platform support" 560 depends on X86_64 561 depends on X86_EXTENDED_PLATFORM 562 ---help--- 563 This option enables system support for the Mellanox Technologies 564 platform. 565 566 Say Y here if you are building a kernel for Mellanox system. 567 568 Otherwise, say N. 569 570config X86_INTEL_LPSS 571 bool "Intel Low Power Subsystem Support" 572 depends on X86 && ACPI 573 select COMMON_CLK 574 select PINCTRL 575 select IOSF_MBI 576 ---help--- 577 Select to build support for Intel Low Power Subsystem such as 578 found on Intel Lynxpoint PCH. Selecting this option enables 579 things like clock tree (common clock framework) and pincontrol 580 which are needed by the LPSS peripheral drivers. 581 582config X86_AMD_PLATFORM_DEVICE 583 bool "AMD ACPI2Platform devices support" 584 depends on ACPI 585 select COMMON_CLK 586 select PINCTRL 587 ---help--- 588 Select to interpret AMD specific ACPI device to platform device 589 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 590 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 591 implemented under PINCTRL subsystem. 592 593config IOSF_MBI 594 tristate "Intel SoC IOSF Sideband support for SoC platforms" 595 depends on PCI 596 ---help--- 597 This option enables sideband register access support for Intel SoC 598 platforms. On these platforms the IOSF sideband is used in lieu of 599 MSR's for some register accesses, mostly but not limited to thermal 600 and power. Drivers may query the availability of this device to 601 determine if they need the sideband in order to work on these 602 platforms. The sideband is available on the following SoC products. 603 This list is not meant to be exclusive. 604 - BayTrail 605 - Braswell 606 - Quark 607 608 You should say Y if you are running a kernel on one of these SoC's. 609 610config IOSF_MBI_DEBUG 611 bool "Enable IOSF sideband access through debugfs" 612 depends on IOSF_MBI && DEBUG_FS 613 ---help--- 614 Select this option to expose the IOSF sideband access registers (MCR, 615 MDR, MCRX) through debugfs to write and read register information from 616 different units on the SoC. This is most useful for obtaining device 617 state information for debug and analysis. As this is a general access 618 mechanism, users of this option would have specific knowledge of the 619 device they want to access. 620 621 If you don't require the option or are in doubt, say N. 622 623config X86_RDC321X 624 bool "RDC R-321x SoC" 625 depends on X86_32 626 depends on X86_EXTENDED_PLATFORM 627 select M486 628 select X86_REBOOTFIXUPS 629 ---help--- 630 This option is needed for RDC R-321x system-on-chip, also known 631 as R-8610-(G). 632 If you don't have one of these chips, you should say N here. 633 634config X86_32_NON_STANDARD 635 bool "Support non-standard 32-bit SMP architectures" 636 depends on X86_32 && SMP 637 depends on X86_EXTENDED_PLATFORM 638 ---help--- 639 This option compiles in the bigsmp and STA2X11 default 640 subarchitectures. It is intended for a generic binary 641 kernel. If you select them all, kernel will probe it one by 642 one and will fallback to default. 643 644# Alphabetically sorted list of Non standard 32 bit platforms 645 646config X86_SUPPORTS_MEMORY_FAILURE 647 def_bool y 648 # MCE code calls memory_failure(): 649 depends on X86_MCE 650 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 651 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 652 depends on X86_64 || !SPARSEMEM 653 select ARCH_SUPPORTS_MEMORY_FAILURE 654 655config STA2X11 656 bool "STA2X11 Companion Chip Support" 657 depends on X86_32_NON_STANDARD && PCI 658 select X86_DEV_DMA_OPS 659 select X86_DMA_REMAP 660 select SWIOTLB 661 select MFD_STA2X11 662 select GPIOLIB 663 default n 664 ---help--- 665 This adds support for boards based on the STA2X11 IO-Hub, 666 a.k.a. "ConneXt". The chip is used in place of the standard 667 PC chipset, so all "standard" peripherals are missing. If this 668 option is selected the kernel will still be able to boot on 669 standard PC machines. 670 671config X86_32_IRIS 672 tristate "Eurobraille/Iris poweroff module" 673 depends on X86_32 674 ---help--- 675 The Iris machines from EuroBraille do not have APM or ACPI support 676 to shut themselves down properly. A special I/O sequence is 677 needed to do so, which is what this module does at 678 kernel shutdown. 679 680 This is only for Iris machines from EuroBraille. 681 682 If unused, say N. 683 684config SCHED_OMIT_FRAME_POINTER 685 def_bool y 686 prompt "Single-depth WCHAN output" 687 depends on X86 688 ---help--- 689 Calculate simpler /proc/<PID>/wchan values. If this option 690 is disabled then wchan values will recurse back to the 691 caller function. This provides more accurate wchan values, 692 at the expense of slightly more scheduling overhead. 693 694 If in doubt, say "Y". 695 696menuconfig HYPERVISOR_GUEST 697 bool "Linux guest support" 698 ---help--- 699 Say Y here to enable options for running Linux under various hyper- 700 visors. This option enables basic hypervisor detection and platform 701 setup. 702 703 If you say N, all options in this submenu will be skipped and 704 disabled, and Linux guest support won't be built in. 705 706if HYPERVISOR_GUEST 707 708config PARAVIRT 709 bool "Enable paravirtualization code" 710 ---help--- 711 This changes the kernel so it can modify itself when it is run 712 under a hypervisor, potentially improving performance significantly 713 over full virtualization. However, when run without a hypervisor 714 the kernel is theoretically slower and slightly larger. 715 716config PARAVIRT_DEBUG 717 bool "paravirt-ops debugging" 718 depends on PARAVIRT && DEBUG_KERNEL 719 ---help--- 720 Enable to debug paravirt_ops internals. Specifically, BUG if 721 a paravirt_op is missing when it is called. 722 723config PARAVIRT_SPINLOCKS 724 bool "Paravirtualization layer for spinlocks" 725 depends on PARAVIRT && SMP 726 ---help--- 727 Paravirtualized spinlocks allow a pvops backend to replace the 728 spinlock implementation with something virtualization-friendly 729 (for example, block the virtual CPU rather than spinning). 730 731 It has a minimal impact on native kernels and gives a nice performance 732 benefit on paravirtualized KVM / Xen kernels. 733 734 If you are unsure how to answer this question, answer Y. 735 736config QUEUED_LOCK_STAT 737 bool "Paravirt queued spinlock statistics" 738 depends on PARAVIRT_SPINLOCKS && DEBUG_FS 739 ---help--- 740 Enable the collection of statistical data on the slowpath 741 behavior of paravirtualized queued spinlocks and report 742 them on debugfs. 743 744source "arch/x86/xen/Kconfig" 745 746config KVM_GUEST 747 bool "KVM Guest support (including kvmclock)" 748 depends on PARAVIRT 749 select PARAVIRT_CLOCK 750 default y 751 ---help--- 752 This option enables various optimizations for running under the KVM 753 hypervisor. It includes a paravirtualized clock, so that instead 754 of relying on a PIT (or probably other) emulation by the 755 underlying device model, the host provides the guest with 756 timing infrastructure such as time of day, and system time 757 758config KVM_DEBUG_FS 759 bool "Enable debug information for KVM Guests in debugfs" 760 depends on KVM_GUEST && DEBUG_FS 761 default n 762 ---help--- 763 This option enables collection of various statistics for KVM guest. 764 Statistics are displayed in debugfs filesystem. Enabling this option 765 may incur significant overhead. 766 767source "arch/x86/lguest/Kconfig" 768 769config PARAVIRT_TIME_ACCOUNTING 770 bool "Paravirtual steal time accounting" 771 depends on PARAVIRT 772 default n 773 ---help--- 774 Select this option to enable fine granularity task steal time 775 accounting. Time spent executing other tasks in parallel with 776 the current vCPU is discounted from the vCPU power. To account for 777 that, there can be a small performance impact. 778 779 If in doubt, say N here. 780 781config PARAVIRT_CLOCK 782 bool 783 784endif #HYPERVISOR_GUEST 785 786config NO_BOOTMEM 787 def_bool y 788 789source "arch/x86/Kconfig.cpu" 790 791config HPET_TIMER 792 def_bool X86_64 793 prompt "HPET Timer Support" if X86_32 794 ---help--- 795 Use the IA-PC HPET (High Precision Event Timer) to manage 796 time in preference to the PIT and RTC, if a HPET is 797 present. 798 HPET is the next generation timer replacing legacy 8254s. 799 The HPET provides a stable time base on SMP 800 systems, unlike the TSC, but it is more expensive to access, 801 as it is off-chip. The interface used is documented 802 in the HPET spec, revision 1. 803 804 You can safely choose Y here. However, HPET will only be 805 activated if the platform and the BIOS support this feature. 806 Otherwise the 8254 will be used for timing services. 807 808 Choose N to continue using the legacy 8254 timer. 809 810config HPET_EMULATE_RTC 811 def_bool y 812 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 813 814config APB_TIMER 815 def_bool y if X86_INTEL_MID 816 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 817 select DW_APB_TIMER 818 depends on X86_INTEL_MID && SFI 819 help 820 APB timer is the replacement for 8254, HPET on X86 MID platforms. 821 The APBT provides a stable time base on SMP 822 systems, unlike the TSC, but it is more expensive to access, 823 as it is off-chip. APB timers are always running regardless of CPU 824 C states, they are used as per CPU clockevent device when possible. 825 826# Mark as expert because too many people got it wrong. 827# The code disables itself when not needed. 828config DMI 829 default y 830 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 831 bool "Enable DMI scanning" if EXPERT 832 ---help--- 833 Enabled scanning of DMI to identify machine quirks. Say Y 834 here unless you have verified that your setup is not 835 affected by entries in the DMI blacklist. Required by PNP 836 BIOS code. 837 838config GART_IOMMU 839 bool "Old AMD GART IOMMU support" 840 select SWIOTLB 841 depends on X86_64 && PCI && AMD_NB 842 ---help--- 843 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 844 GART based hardware IOMMUs. 845 846 The GART supports full DMA access for devices with 32-bit access 847 limitations, on systems with more than 3 GB. This is usually needed 848 for USB, sound, many IDE/SATA chipsets and some other devices. 849 850 Newer systems typically have a modern AMD IOMMU, supported via 851 the CONFIG_AMD_IOMMU=y config option. 852 853 In normal configurations this driver is only active when needed: 854 there's more than 3 GB of memory and the system contains a 855 32-bit limited device. 856 857 If unsure, say Y. 858 859config CALGARY_IOMMU 860 bool "IBM Calgary IOMMU support" 861 select SWIOTLB 862 depends on X86_64 && PCI 863 ---help--- 864 Support for hardware IOMMUs in IBM's xSeries x366 and x460 865 systems. Needed to run systems with more than 3GB of memory 866 properly with 32-bit PCI devices that do not support DAC 867 (Double Address Cycle). Calgary also supports bus level 868 isolation, where all DMAs pass through the IOMMU. This 869 prevents them from going anywhere except their intended 870 destination. This catches hard-to-find kernel bugs and 871 mis-behaving drivers and devices that do not use the DMA-API 872 properly to set up their DMA buffers. The IOMMU can be 873 turned off at boot time with the iommu=off parameter. 874 Normally the kernel will make the right choice by itself. 875 If unsure, say Y. 876 877config CALGARY_IOMMU_ENABLED_BY_DEFAULT 878 def_bool y 879 prompt "Should Calgary be enabled by default?" 880 depends on CALGARY_IOMMU 881 ---help--- 882 Should Calgary be enabled by default? if you choose 'y', Calgary 883 will be used (if it exists). If you choose 'n', Calgary will not be 884 used even if it exists. If you choose 'n' and would like to use 885 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 886 If unsure, say Y. 887 888# need this always selected by IOMMU for the VIA workaround 889config SWIOTLB 890 def_bool y if X86_64 891 ---help--- 892 Support for software bounce buffers used on x86-64 systems 893 which don't have a hardware IOMMU. Using this PCI devices 894 which can only access 32-bits of memory can be used on systems 895 with more than 3 GB of memory. 896 If unsure, say Y. 897 898config IOMMU_HELPER 899 def_bool y 900 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 901 902config MAXSMP 903 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 904 depends on X86_64 && SMP && DEBUG_KERNEL 905 select CPUMASK_OFFSTACK 906 ---help--- 907 Enable maximum number of CPUS and NUMA Nodes for this architecture. 908 If unsure, say N. 909 910config NR_CPUS 911 int "Maximum number of CPUs" if SMP && !MAXSMP 912 range 2 8 if SMP && X86_32 && !X86_BIGSMP 913 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 914 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 915 default "1" if !SMP 916 default "8192" if MAXSMP 917 default "32" if SMP && X86_BIGSMP 918 default "8" if SMP && X86_32 919 default "64" if SMP 920 ---help--- 921 This allows you to specify the maximum number of CPUs which this 922 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 923 supported value is 8192, otherwise the maximum value is 512. The 924 minimum value which makes sense is 2. 925 926 This is purely to save memory - each supported CPU adds 927 approximately eight kilobytes to the kernel image. 928 929config SCHED_SMT 930 bool "SMT (Hyperthreading) scheduler support" 931 depends on SMP 932 ---help--- 933 SMT scheduler support improves the CPU scheduler's decision making 934 when dealing with Intel Pentium 4 chips with HyperThreading at a 935 cost of slightly increased overhead in some places. If unsure say 936 N here. 937 938config SCHED_MC 939 def_bool y 940 prompt "Multi-core scheduler support" 941 depends on SMP 942 ---help--- 943 Multi-core scheduler support improves the CPU scheduler's decision 944 making when dealing with multi-core CPU chips at a cost of slightly 945 increased overhead in some places. If unsure say N here. 946 947config SCHED_MC_PRIO 948 bool "CPU core priorities scheduler support" 949 depends on SCHED_MC && CPU_SUP_INTEL 950 select X86_INTEL_PSTATE 951 select CPU_FREQ 952 default y 953 ---help--- 954 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 955 core ordering determined at manufacturing time, which allows 956 certain cores to reach higher turbo frequencies (when running 957 single threaded workloads) than others. 958 959 Enabling this kernel feature teaches the scheduler about 960 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 961 scheduler's CPU selection logic accordingly, so that higher 962 overall system performance can be achieved. 963 964 This feature will have no effect on CPUs without this feature. 965 966 If unsure say Y here. 967 968source "kernel/Kconfig.preempt" 969 970config UP_LATE_INIT 971 def_bool y 972 depends on !SMP && X86_LOCAL_APIC 973 974config X86_UP_APIC 975 bool "Local APIC support on uniprocessors" if !PCI_MSI 976 default PCI_MSI 977 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 978 ---help--- 979 A local APIC (Advanced Programmable Interrupt Controller) is an 980 integrated interrupt controller in the CPU. If you have a single-CPU 981 system which has a processor with a local APIC, you can say Y here to 982 enable and use it. If you say Y here even though your machine doesn't 983 have a local APIC, then the kernel will still run with no slowdown at 984 all. The local APIC supports CPU-generated self-interrupts (timer, 985 performance counters), and the NMI watchdog which detects hard 986 lockups. 987 988config X86_UP_IOAPIC 989 bool "IO-APIC support on uniprocessors" 990 depends on X86_UP_APIC 991 ---help--- 992 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 993 SMP-capable replacement for PC-style interrupt controllers. Most 994 SMP systems and many recent uniprocessor systems have one. 995 996 If you have a single-CPU system with an IO-APIC, you can say Y here 997 to use it. If you say Y here even though your machine doesn't have 998 an IO-APIC, then the kernel will still run with no slowdown at all. 999 1000config X86_LOCAL_APIC 1001 def_bool y 1002 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1003 select IRQ_DOMAIN_HIERARCHY 1004 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1005 1006config X86_IO_APIC 1007 def_bool y 1008 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1009 1010config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 1011 bool "Reroute for broken boot IRQs" 1012 depends on X86_IO_APIC 1013 ---help--- 1014 This option enables a workaround that fixes a source of 1015 spurious interrupts. This is recommended when threaded 1016 interrupt handling is used on systems where the generation of 1017 superfluous "boot interrupts" cannot be disabled. 1018 1019 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 1020 entry in the chipset's IO-APIC is masked (as, e.g. the RT 1021 kernel does during interrupt handling). On chipsets where this 1022 boot IRQ generation cannot be disabled, this workaround keeps 1023 the original IRQ line masked so that only the equivalent "boot 1024 IRQ" is delivered to the CPUs. The workaround also tells the 1025 kernel to set up the IRQ handler on the boot IRQ line. In this 1026 way only one interrupt is delivered to the kernel. Otherwise 1027 the spurious second interrupt may cause the kernel to bring 1028 down (vital) interrupt lines. 1029 1030 Only affects "broken" chipsets. Interrupt sharing may be 1031 increased on these systems. 1032 1033config X86_MCE 1034 bool "Machine Check / overheating reporting" 1035 select GENERIC_ALLOCATOR 1036 default y 1037 ---help--- 1038 Machine Check support allows the processor to notify the 1039 kernel if it detects a problem (e.g. overheating, data corruption). 1040 The action the kernel takes depends on the severity of the problem, 1041 ranging from warning messages to halting the machine. 1042 1043config X86_MCE_INTEL 1044 def_bool y 1045 prompt "Intel MCE features" 1046 depends on X86_MCE && X86_LOCAL_APIC 1047 ---help--- 1048 Additional support for intel specific MCE features such as 1049 the thermal monitor. 1050 1051config X86_MCE_AMD 1052 def_bool y 1053 prompt "AMD MCE features" 1054 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 1055 ---help--- 1056 Additional support for AMD specific MCE features such as 1057 the DRAM Error Threshold. 1058 1059config X86_ANCIENT_MCE 1060 bool "Support for old Pentium 5 / WinChip machine checks" 1061 depends on X86_32 && X86_MCE 1062 ---help--- 1063 Include support for machine check handling on old Pentium 5 or WinChip 1064 systems. These typically need to be enabled explicitly on the command 1065 line. 1066 1067config X86_MCE_THRESHOLD 1068 depends on X86_MCE_AMD || X86_MCE_INTEL 1069 def_bool y 1070 1071config X86_MCE_INJECT 1072 depends on X86_MCE 1073 tristate "Machine check injector support" 1074 ---help--- 1075 Provide support for injecting machine checks for testing purposes. 1076 If you don't know what a machine check is and you don't do kernel 1077 QA it is safe to say n. 1078 1079config X86_THERMAL_VECTOR 1080 def_bool y 1081 depends on X86_MCE_INTEL 1082 1083source "arch/x86/events/Kconfig" 1084 1085config X86_LEGACY_VM86 1086 bool "Legacy VM86 support" 1087 default n 1088 depends on X86_32 1089 ---help--- 1090 This option allows user programs to put the CPU into V8086 1091 mode, which is an 80286-era approximation of 16-bit real mode. 1092 1093 Some very old versions of X and/or vbetool require this option 1094 for user mode setting. Similarly, DOSEMU will use it if 1095 available to accelerate real mode DOS programs. However, any 1096 recent version of DOSEMU, X, or vbetool should be fully 1097 functional even without kernel VM86 support, as they will all 1098 fall back to software emulation. Nevertheless, if you are using 1099 a 16-bit DOS program where 16-bit performance matters, vm86 1100 mode might be faster than emulation and you might want to 1101 enable this option. 1102 1103 Note that any app that works on a 64-bit kernel is unlikely to 1104 need this option, as 64-bit kernels don't, and can't, support 1105 V8086 mode. This option is also unrelated to 16-bit protected 1106 mode and is not needed to run most 16-bit programs under Wine. 1107 1108 Enabling this option increases the complexity of the kernel 1109 and slows down exception handling a tiny bit. 1110 1111 If unsure, say N here. 1112 1113config VM86 1114 bool 1115 default X86_LEGACY_VM86 1116 1117config X86_16BIT 1118 bool "Enable support for 16-bit segments" if EXPERT 1119 default y 1120 depends on MODIFY_LDT_SYSCALL 1121 ---help--- 1122 This option is required by programs like Wine to run 16-bit 1123 protected mode legacy code on x86 processors. Disabling 1124 this option saves about 300 bytes on i386, or around 6K text 1125 plus 16K runtime memory on x86-64, 1126 1127config X86_ESPFIX32 1128 def_bool y 1129 depends on X86_16BIT && X86_32 1130 1131config X86_ESPFIX64 1132 def_bool y 1133 depends on X86_16BIT && X86_64 1134 1135config X86_VSYSCALL_EMULATION 1136 bool "Enable vsyscall emulation" if EXPERT 1137 default y 1138 depends on X86_64 1139 ---help--- 1140 This enables emulation of the legacy vsyscall page. Disabling 1141 it is roughly equivalent to booting with vsyscall=none, except 1142 that it will also disable the helpful warning if a program 1143 tries to use a vsyscall. With this option set to N, offending 1144 programs will just segfault, citing addresses of the form 1145 0xffffffffff600?00. 1146 1147 This option is required by many programs built before 2013, and 1148 care should be used even with newer programs if set to N. 1149 1150 Disabling this option saves about 7K of kernel size and 1151 possibly 4K of additional runtime pagetable memory. 1152 1153config TOSHIBA 1154 tristate "Toshiba Laptop support" 1155 depends on X86_32 1156 ---help--- 1157 This adds a driver to safely access the System Management Mode of 1158 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1159 not work on models with a Phoenix BIOS. The System Management Mode 1160 is used to set the BIOS and power saving options on Toshiba portables. 1161 1162 For information on utilities to make use of this driver see the 1163 Toshiba Linux utilities web site at: 1164 <http://www.buzzard.org.uk/toshiba/>. 1165 1166 Say Y if you intend to run this kernel on a Toshiba portable. 1167 Say N otherwise. 1168 1169config I8K 1170 tristate "Dell i8k legacy laptop support" 1171 select HWMON 1172 select SENSORS_DELL_SMM 1173 ---help--- 1174 This option enables legacy /proc/i8k userspace interface in hwmon 1175 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1176 temperature and allows controlling fan speeds of Dell laptops via 1177 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1178 it reports also power and hotkey status. For fan speed control is 1179 needed userspace package i8kutils. 1180 1181 Say Y if you intend to run this kernel on old Dell laptops or want to 1182 use userspace package i8kutils. 1183 Say N otherwise. 1184 1185config X86_REBOOTFIXUPS 1186 bool "Enable X86 board specific fixups for reboot" 1187 depends on X86_32 1188 ---help--- 1189 This enables chipset and/or board specific fixups to be done 1190 in order to get reboot to work correctly. This is only needed on 1191 some combinations of hardware and BIOS. The symptom, for which 1192 this config is intended, is when reboot ends with a stalled/hung 1193 system. 1194 1195 Currently, the only fixup is for the Geode machines using 1196 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1197 1198 Say Y if you want to enable the fixup. Currently, it's safe to 1199 enable this option even if you don't need it. 1200 Say N otherwise. 1201 1202config MICROCODE 1203 bool "CPU microcode loading support" 1204 default y 1205 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1206 select FW_LOADER 1207 ---help--- 1208 If you say Y here, you will be able to update the microcode on 1209 Intel and AMD processors. The Intel support is for the IA32 family, 1210 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1211 AMD support is for families 0x10 and later. You will obviously need 1212 the actual microcode binary data itself which is not shipped with 1213 the Linux kernel. 1214 1215 The preferred method to load microcode from a detached initrd is described 1216 in Documentation/x86/early-microcode.txt. For that you need to enable 1217 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1218 initrd for microcode blobs. 1219 1220 In addition, you can build-in the microcode into the kernel. For that you 1221 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 1222 to the CONFIG_EXTRA_FIRMWARE config option. 1223 1224config MICROCODE_INTEL 1225 bool "Intel microcode loading support" 1226 depends on MICROCODE 1227 default MICROCODE 1228 select FW_LOADER 1229 ---help--- 1230 This options enables microcode patch loading support for Intel 1231 processors. 1232 1233 For the current Intel microcode data package go to 1234 <https://downloadcenter.intel.com> and search for 1235 'Linux Processor Microcode Data File'. 1236 1237config MICROCODE_AMD 1238 bool "AMD microcode loading support" 1239 depends on MICROCODE 1240 select FW_LOADER 1241 ---help--- 1242 If you select this option, microcode patch loading support for AMD 1243 processors will be enabled. 1244 1245config MICROCODE_OLD_INTERFACE 1246 def_bool y 1247 depends on MICROCODE 1248 1249config X86_MSR 1250 tristate "/dev/cpu/*/msr - Model-specific register support" 1251 ---help--- 1252 This device gives privileged processes access to the x86 1253 Model-Specific Registers (MSRs). It is a character device with 1254 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1255 MSR accesses are directed to a specific CPU on multi-processor 1256 systems. 1257 1258config X86_CPUID 1259 tristate "/dev/cpu/*/cpuid - CPU information support" 1260 ---help--- 1261 This device gives processes access to the x86 CPUID instruction to 1262 be executed on a specific processor. It is a character device 1263 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1264 /dev/cpu/31/cpuid. 1265 1266choice 1267 prompt "High Memory Support" 1268 default HIGHMEM4G 1269 depends on X86_32 1270 1271config NOHIGHMEM 1272 bool "off" 1273 ---help--- 1274 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1275 However, the address space of 32-bit x86 processors is only 4 1276 Gigabytes large. That means that, if you have a large amount of 1277 physical memory, not all of it can be "permanently mapped" by the 1278 kernel. The physical memory that's not permanently mapped is called 1279 "high memory". 1280 1281 If you are compiling a kernel which will never run on a machine with 1282 more than 1 Gigabyte total physical RAM, answer "off" here (default 1283 choice and suitable for most users). This will result in a "3GB/1GB" 1284 split: 3GB are mapped so that each process sees a 3GB virtual memory 1285 space and the remaining part of the 4GB virtual memory space is used 1286 by the kernel to permanently map as much physical memory as 1287 possible. 1288 1289 If the machine has between 1 and 4 Gigabytes physical RAM, then 1290 answer "4GB" here. 1291 1292 If more than 4 Gigabytes is used then answer "64GB" here. This 1293 selection turns Intel PAE (Physical Address Extension) mode on. 1294 PAE implements 3-level paging on IA32 processors. PAE is fully 1295 supported by Linux, PAE mode is implemented on all recent Intel 1296 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1297 then the kernel will not boot on CPUs that don't support PAE! 1298 1299 The actual amount of total physical memory will either be 1300 auto detected or can be forced by using a kernel command line option 1301 such as "mem=256M". (Try "man bootparam" or see the documentation of 1302 your boot loader (lilo or loadlin) about how to pass options to the 1303 kernel at boot time.) 1304 1305 If unsure, say "off". 1306 1307config HIGHMEM4G 1308 bool "4GB" 1309 ---help--- 1310 Select this if you have a 32-bit processor and between 1 and 4 1311 gigabytes of physical RAM. 1312 1313config HIGHMEM64G 1314 bool "64GB" 1315 depends on !M486 1316 select X86_PAE 1317 ---help--- 1318 Select this if you have a 32-bit processor and more than 4 1319 gigabytes of physical RAM. 1320 1321endchoice 1322 1323choice 1324 prompt "Memory split" if EXPERT 1325 default VMSPLIT_3G 1326 depends on X86_32 1327 ---help--- 1328 Select the desired split between kernel and user memory. 1329 1330 If the address range available to the kernel is less than the 1331 physical memory installed, the remaining memory will be available 1332 as "high memory". Accessing high memory is a little more costly 1333 than low memory, as it needs to be mapped into the kernel first. 1334 Note that increasing the kernel address space limits the range 1335 available to user programs, making the address space there 1336 tighter. Selecting anything other than the default 3G/1G split 1337 will also likely make your kernel incompatible with binary-only 1338 kernel modules. 1339 1340 If you are not absolutely sure what you are doing, leave this 1341 option alone! 1342 1343 config VMSPLIT_3G 1344 bool "3G/1G user/kernel split" 1345 config VMSPLIT_3G_OPT 1346 depends on !X86_PAE 1347 bool "3G/1G user/kernel split (for full 1G low memory)" 1348 config VMSPLIT_2G 1349 bool "2G/2G user/kernel split" 1350 config VMSPLIT_2G_OPT 1351 depends on !X86_PAE 1352 bool "2G/2G user/kernel split (for full 2G low memory)" 1353 config VMSPLIT_1G 1354 bool "1G/3G user/kernel split" 1355endchoice 1356 1357config PAGE_OFFSET 1358 hex 1359 default 0xB0000000 if VMSPLIT_3G_OPT 1360 default 0x80000000 if VMSPLIT_2G 1361 default 0x78000000 if VMSPLIT_2G_OPT 1362 default 0x40000000 if VMSPLIT_1G 1363 default 0xC0000000 1364 depends on X86_32 1365 1366config HIGHMEM 1367 def_bool y 1368 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1369 1370config X86_PAE 1371 bool "PAE (Physical Address Extension) Support" 1372 depends on X86_32 && !HIGHMEM4G 1373 select SWIOTLB 1374 ---help--- 1375 PAE is required for NX support, and furthermore enables 1376 larger swapspace support for non-overcommit purposes. It 1377 has the cost of more pagetable lookup overhead, and also 1378 consumes more pagetable space per process. 1379 1380config ARCH_PHYS_ADDR_T_64BIT 1381 def_bool y 1382 depends on X86_64 || X86_PAE 1383 1384config ARCH_DMA_ADDR_T_64BIT 1385 def_bool y 1386 depends on X86_64 || HIGHMEM64G 1387 1388config X86_DIRECT_GBPAGES 1389 def_bool y 1390 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1391 ---help--- 1392 Certain kernel features effectively disable kernel 1393 linear 1 GB mappings (even if the CPU otherwise 1394 supports them), so don't confuse the user by printing 1395 that we have them enabled. 1396 1397# Common NUMA Features 1398config NUMA 1399 bool "Numa Memory Allocation and Scheduler Support" 1400 depends on SMP 1401 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1402 default y if X86_BIGSMP 1403 ---help--- 1404 Enable NUMA (Non Uniform Memory Access) support. 1405 1406 The kernel will try to allocate memory used by a CPU on the 1407 local memory controller of the CPU and add some more 1408 NUMA awareness to the kernel. 1409 1410 For 64-bit this is recommended if the system is Intel Core i7 1411 (or later), AMD Opteron, or EM64T NUMA. 1412 1413 For 32-bit this is only needed if you boot a 32-bit 1414 kernel on a 64-bit NUMA platform. 1415 1416 Otherwise, you should say N. 1417 1418config AMD_NUMA 1419 def_bool y 1420 prompt "Old style AMD Opteron NUMA detection" 1421 depends on X86_64 && NUMA && PCI 1422 ---help--- 1423 Enable AMD NUMA node topology detection. You should say Y here if 1424 you have a multi processor AMD system. This uses an old method to 1425 read the NUMA configuration directly from the builtin Northbridge 1426 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1427 which also takes priority if both are compiled in. 1428 1429config X86_64_ACPI_NUMA 1430 def_bool y 1431 prompt "ACPI NUMA detection" 1432 depends on X86_64 && NUMA && ACPI && PCI 1433 select ACPI_NUMA 1434 ---help--- 1435 Enable ACPI SRAT based node topology detection. 1436 1437# Some NUMA nodes have memory ranges that span 1438# other nodes. Even though a pfn is valid and 1439# between a node's start and end pfns, it may not 1440# reside on that node. See memmap_init_zone() 1441# for details. 1442config NODES_SPAN_OTHER_NODES 1443 def_bool y 1444 depends on X86_64_ACPI_NUMA 1445 1446config NUMA_EMU 1447 bool "NUMA emulation" 1448 depends on NUMA 1449 ---help--- 1450 Enable NUMA emulation. A flat machine will be split 1451 into virtual nodes when booted with "numa=fake=N", where N is the 1452 number of nodes. This is only useful for debugging. 1453 1454config NODES_SHIFT 1455 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1456 range 1 10 1457 default "10" if MAXSMP 1458 default "6" if X86_64 1459 default "3" 1460 depends on NEED_MULTIPLE_NODES 1461 ---help--- 1462 Specify the maximum number of NUMA Nodes available on the target 1463 system. Increases memory reserved to accommodate various tables. 1464 1465config ARCH_HAVE_MEMORY_PRESENT 1466 def_bool y 1467 depends on X86_32 && DISCONTIGMEM 1468 1469config NEED_NODE_MEMMAP_SIZE 1470 def_bool y 1471 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1472 1473config ARCH_FLATMEM_ENABLE 1474 def_bool y 1475 depends on X86_32 && !NUMA 1476 1477config ARCH_DISCONTIGMEM_ENABLE 1478 def_bool y 1479 depends on NUMA && X86_32 1480 1481config ARCH_DISCONTIGMEM_DEFAULT 1482 def_bool y 1483 depends on NUMA && X86_32 1484 1485config ARCH_SPARSEMEM_ENABLE 1486 def_bool y 1487 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1488 select SPARSEMEM_STATIC if X86_32 1489 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1490 1491config ARCH_SPARSEMEM_DEFAULT 1492 def_bool y 1493 depends on X86_64 1494 1495config ARCH_SELECT_MEMORY_MODEL 1496 def_bool y 1497 depends on ARCH_SPARSEMEM_ENABLE 1498 1499config ARCH_MEMORY_PROBE 1500 bool "Enable sysfs memory/probe interface" 1501 depends on X86_64 && MEMORY_HOTPLUG 1502 help 1503 This option enables a sysfs memory/probe interface for testing. 1504 See Documentation/memory-hotplug.txt for more information. 1505 If you are unsure how to answer this question, answer N. 1506 1507config ARCH_PROC_KCORE_TEXT 1508 def_bool y 1509 depends on X86_64 && PROC_KCORE 1510 1511config ILLEGAL_POINTER_VALUE 1512 hex 1513 default 0 if X86_32 1514 default 0xdead000000000000 if X86_64 1515 1516source "mm/Kconfig" 1517 1518config X86_PMEM_LEGACY_DEVICE 1519 bool 1520 1521config X86_PMEM_LEGACY 1522 tristate "Support non-standard NVDIMMs and ADR protected memory" 1523 depends on PHYS_ADDR_T_64BIT 1524 depends on BLK_DEV 1525 select X86_PMEM_LEGACY_DEVICE 1526 select LIBNVDIMM 1527 help 1528 Treat memory marked using the non-standard e820 type of 12 as used 1529 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1530 The kernel will offer these regions to the 'pmem' driver so 1531 they can be used for persistent storage. 1532 1533 Say Y if unsure. 1534 1535config HIGHPTE 1536 bool "Allocate 3rd-level pagetables from highmem" 1537 depends on HIGHMEM 1538 ---help--- 1539 The VM uses one page table entry for each page of physical memory. 1540 For systems with a lot of RAM, this can be wasteful of precious 1541 low memory. Setting this option will put user-space page table 1542 entries in high memory. 1543 1544config X86_CHECK_BIOS_CORRUPTION 1545 bool "Check for low memory corruption" 1546 ---help--- 1547 Periodically check for memory corruption in low memory, which 1548 is suspected to be caused by BIOS. Even when enabled in the 1549 configuration, it is disabled at runtime. Enable it by 1550 setting "memory_corruption_check=1" on the kernel command 1551 line. By default it scans the low 64k of memory every 60 1552 seconds; see the memory_corruption_check_size and 1553 memory_corruption_check_period parameters in 1554 Documentation/admin-guide/kernel-parameters.rst to adjust this. 1555 1556 When enabled with the default parameters, this option has 1557 almost no overhead, as it reserves a relatively small amount 1558 of memory and scans it infrequently. It both detects corruption 1559 and prevents it from affecting the running system. 1560 1561 It is, however, intended as a diagnostic tool; if repeatable 1562 BIOS-originated corruption always affects the same memory, 1563 you can use memmap= to prevent the kernel from using that 1564 memory. 1565 1566config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1567 bool "Set the default setting of memory_corruption_check" 1568 depends on X86_CHECK_BIOS_CORRUPTION 1569 default y 1570 ---help--- 1571 Set whether the default state of memory_corruption_check is 1572 on or off. 1573 1574config X86_RESERVE_LOW 1575 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1576 default 64 1577 range 4 640 1578 ---help--- 1579 Specify the amount of low memory to reserve for the BIOS. 1580 1581 The first page contains BIOS data structures that the kernel 1582 must not use, so that page must always be reserved. 1583 1584 By default we reserve the first 64K of physical RAM, as a 1585 number of BIOSes are known to corrupt that memory range 1586 during events such as suspend/resume or monitor cable 1587 insertion, so it must not be used by the kernel. 1588 1589 You can set this to 4 if you are absolutely sure that you 1590 trust the BIOS to get all its memory reservations and usages 1591 right. If you know your BIOS have problems beyond the 1592 default 64K area, you can set this to 640 to avoid using the 1593 entire low memory range. 1594 1595 If you have doubts about the BIOS (e.g. suspend/resume does 1596 not work or there's kernel crashes after certain hardware 1597 hotplug events) then you might want to enable 1598 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1599 typical corruption patterns. 1600 1601 Leave this to the default value of 64 if you are unsure. 1602 1603config MATH_EMULATION 1604 bool 1605 depends on MODIFY_LDT_SYSCALL 1606 prompt "Math emulation" if X86_32 1607 ---help--- 1608 Linux can emulate a math coprocessor (used for floating point 1609 operations) if you don't have one. 486DX and Pentium processors have 1610 a math coprocessor built in, 486SX and 386 do not, unless you added 1611 a 487DX or 387, respectively. (The messages during boot time can 1612 give you some hints here ["man dmesg"].) Everyone needs either a 1613 coprocessor or this emulation. 1614 1615 If you don't have a math coprocessor, you need to say Y here; if you 1616 say Y here even though you have a coprocessor, the coprocessor will 1617 be used nevertheless. (This behavior can be changed with the kernel 1618 command line option "no387", which comes handy if your coprocessor 1619 is broken. Try "man bootparam" or see the documentation of your boot 1620 loader (lilo or loadlin) about how to pass options to the kernel at 1621 boot time.) This means that it is a good idea to say Y here if you 1622 intend to use this kernel on different machines. 1623 1624 More information about the internals of the Linux math coprocessor 1625 emulation can be found in <file:arch/x86/math-emu/README>. 1626 1627 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1628 kernel, it won't hurt. 1629 1630config MTRR 1631 def_bool y 1632 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1633 ---help--- 1634 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1635 the Memory Type Range Registers (MTRRs) may be used to control 1636 processor access to memory ranges. This is most useful if you have 1637 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1638 allows bus write transfers to be combined into a larger transfer 1639 before bursting over the PCI/AGP bus. This can increase performance 1640 of image write operations 2.5 times or more. Saying Y here creates a 1641 /proc/mtrr file which may be used to manipulate your processor's 1642 MTRRs. Typically the X server should use this. 1643 1644 This code has a reasonably generic interface so that similar 1645 control registers on other processors can be easily supported 1646 as well: 1647 1648 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1649 Registers (ARRs) which provide a similar functionality to MTRRs. For 1650 these, the ARRs are used to emulate the MTRRs. 1651 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1652 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1653 write-combining. All of these processors are supported by this code 1654 and it makes sense to say Y here if you have one of them. 1655 1656 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1657 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1658 can lead to all sorts of problems, so it's good to say Y here. 1659 1660 You can safely say Y even if your machine doesn't have MTRRs, you'll 1661 just add about 9 KB to your kernel. 1662 1663 See <file:Documentation/x86/mtrr.txt> for more information. 1664 1665config MTRR_SANITIZER 1666 def_bool y 1667 prompt "MTRR cleanup support" 1668 depends on MTRR 1669 ---help--- 1670 Convert MTRR layout from continuous to discrete, so X drivers can 1671 add writeback entries. 1672 1673 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1674 The largest mtrr entry size for a continuous block can be set with 1675 mtrr_chunk_size. 1676 1677 If unsure, say Y. 1678 1679config MTRR_SANITIZER_ENABLE_DEFAULT 1680 int "MTRR cleanup enable value (0-1)" 1681 range 0 1 1682 default "0" 1683 depends on MTRR_SANITIZER 1684 ---help--- 1685 Enable mtrr cleanup default value 1686 1687config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1688 int "MTRR cleanup spare reg num (0-7)" 1689 range 0 7 1690 default "1" 1691 depends on MTRR_SANITIZER 1692 ---help--- 1693 mtrr cleanup spare entries default, it can be changed via 1694 mtrr_spare_reg_nr=N on the kernel command line. 1695 1696config X86_PAT 1697 def_bool y 1698 prompt "x86 PAT support" if EXPERT 1699 depends on MTRR 1700 ---help--- 1701 Use PAT attributes to setup page level cache control. 1702 1703 PATs are the modern equivalents of MTRRs and are much more 1704 flexible than MTRRs. 1705 1706 Say N here if you see bootup problems (boot crash, boot hang, 1707 spontaneous reboots) or a non-working video driver. 1708 1709 If unsure, say Y. 1710 1711config ARCH_USES_PG_UNCACHED 1712 def_bool y 1713 depends on X86_PAT 1714 1715config ARCH_RANDOM 1716 def_bool y 1717 prompt "x86 architectural random number generator" if EXPERT 1718 ---help--- 1719 Enable the x86 architectural RDRAND instruction 1720 (Intel Bull Mountain technology) to generate random numbers. 1721 If supported, this is a high bandwidth, cryptographically 1722 secure hardware random number generator. 1723 1724config X86_SMAP 1725 def_bool y 1726 prompt "Supervisor Mode Access Prevention" if EXPERT 1727 ---help--- 1728 Supervisor Mode Access Prevention (SMAP) is a security 1729 feature in newer Intel processors. There is a small 1730 performance cost if this enabled and turned on; there is 1731 also a small increase in the kernel size if this is enabled. 1732 1733 If unsure, say Y. 1734 1735config X86_INTEL_MPX 1736 prompt "Intel MPX (Memory Protection Extensions)" 1737 def_bool n 1738 depends on CPU_SUP_INTEL 1739 ---help--- 1740 MPX provides hardware features that can be used in 1741 conjunction with compiler-instrumented code to check 1742 memory references. It is designed to detect buffer 1743 overflow or underflow bugs. 1744 1745 This option enables running applications which are 1746 instrumented or otherwise use MPX. It does not use MPX 1747 itself inside the kernel or to protect the kernel 1748 against bad memory references. 1749 1750 Enabling this option will make the kernel larger: 1751 ~8k of kernel text and 36 bytes of data on a 64-bit 1752 defconfig. It adds a long to the 'mm_struct' which 1753 will increase the kernel memory overhead of each 1754 process and adds some branches to paths used during 1755 exec() and munmap(). 1756 1757 For details, see Documentation/x86/intel_mpx.txt 1758 1759 If unsure, say N. 1760 1761config X86_INTEL_MEMORY_PROTECTION_KEYS 1762 prompt "Intel Memory Protection Keys" 1763 def_bool y 1764 # Note: only available in 64-bit mode 1765 depends on CPU_SUP_INTEL && X86_64 1766 select ARCH_USES_HIGH_VMA_FLAGS 1767 select ARCH_HAS_PKEYS 1768 ---help--- 1769 Memory Protection Keys provides a mechanism for enforcing 1770 page-based protections, but without requiring modification of the 1771 page tables when an application changes protection domains. 1772 1773 For details, see Documentation/x86/protection-keys.txt 1774 1775 If unsure, say y. 1776 1777config EFI 1778 bool "EFI runtime service support" 1779 depends on ACPI 1780 select UCS2_STRING 1781 select EFI_RUNTIME_WRAPPERS 1782 ---help--- 1783 This enables the kernel to use EFI runtime services that are 1784 available (such as the EFI variable services). 1785 1786 This option is only useful on systems that have EFI firmware. 1787 In addition, you should use the latest ELILO loader available 1788 at <http://elilo.sourceforge.net> in order to take advantage 1789 of EFI runtime services. However, even with this option, the 1790 resultant kernel should continue to boot on existing non-EFI 1791 platforms. 1792 1793config EFI_STUB 1794 bool "EFI stub support" 1795 depends on EFI && !X86_USE_3DNOW 1796 select RELOCATABLE 1797 ---help--- 1798 This kernel feature allows a bzImage to be loaded directly 1799 by EFI firmware without the use of a bootloader. 1800 1801 See Documentation/efi-stub.txt for more information. 1802 1803config EFI_MIXED 1804 bool "EFI mixed-mode support" 1805 depends on EFI_STUB && X86_64 1806 ---help--- 1807 Enabling this feature allows a 64-bit kernel to be booted 1808 on a 32-bit firmware, provided that your CPU supports 64-bit 1809 mode. 1810 1811 Note that it is not possible to boot a mixed-mode enabled 1812 kernel via the EFI boot stub - a bootloader that supports 1813 the EFI handover protocol must be used. 1814 1815 If unsure, say N. 1816 1817config SECCOMP 1818 def_bool y 1819 prompt "Enable seccomp to safely compute untrusted bytecode" 1820 ---help--- 1821 This kernel feature is useful for number crunching applications 1822 that may need to compute untrusted bytecode during their 1823 execution. By using pipes or other transports made available to 1824 the process as file descriptors supporting the read/write 1825 syscalls, it's possible to isolate those applications in 1826 their own address space using seccomp. Once seccomp is 1827 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1828 and the task is only allowed to execute a few safe syscalls 1829 defined by each seccomp mode. 1830 1831 If unsure, say Y. Only embedded should say N here. 1832 1833source kernel/Kconfig.hz 1834 1835config KEXEC 1836 bool "kexec system call" 1837 select KEXEC_CORE 1838 ---help--- 1839 kexec is a system call that implements the ability to shutdown your 1840 current kernel, and to start another kernel. It is like a reboot 1841 but it is independent of the system firmware. And like a reboot 1842 you can start any kernel with it, not just Linux. 1843 1844 The name comes from the similarity to the exec system call. 1845 1846 It is an ongoing process to be certain the hardware in a machine 1847 is properly shutdown, so do not be surprised if this code does not 1848 initially work for you. As of this writing the exact hardware 1849 interface is strongly in flux, so no good recommendation can be 1850 made. 1851 1852config KEXEC_FILE 1853 bool "kexec file based system call" 1854 select KEXEC_CORE 1855 select BUILD_BIN2C 1856 depends on X86_64 1857 depends on CRYPTO=y 1858 depends on CRYPTO_SHA256=y 1859 ---help--- 1860 This is new version of kexec system call. This system call is 1861 file based and takes file descriptors as system call argument 1862 for kernel and initramfs as opposed to list of segments as 1863 accepted by previous system call. 1864 1865config KEXEC_VERIFY_SIG 1866 bool "Verify kernel signature during kexec_file_load() syscall" 1867 depends on KEXEC_FILE 1868 ---help--- 1869 This option makes kernel signature verification mandatory for 1870 the kexec_file_load() syscall. 1871 1872 In addition to that option, you need to enable signature 1873 verification for the corresponding kernel image type being 1874 loaded in order for this to work. 1875 1876config KEXEC_BZIMAGE_VERIFY_SIG 1877 bool "Enable bzImage signature verification support" 1878 depends on KEXEC_VERIFY_SIG 1879 depends on SIGNED_PE_FILE_VERIFICATION 1880 select SYSTEM_TRUSTED_KEYRING 1881 ---help--- 1882 Enable bzImage signature verification support. 1883 1884config CRASH_DUMP 1885 bool "kernel crash dumps" 1886 depends on X86_64 || (X86_32 && HIGHMEM) 1887 ---help--- 1888 Generate crash dump after being started by kexec. 1889 This should be normally only set in special crash dump kernels 1890 which are loaded in the main kernel with kexec-tools into 1891 a specially reserved region and then later executed after 1892 a crash by kdump/kexec. The crash dump kernel must be compiled 1893 to a memory address not used by the main kernel or BIOS using 1894 PHYSICAL_START, or it must be built as a relocatable image 1895 (CONFIG_RELOCATABLE=y). 1896 For more details see Documentation/kdump/kdump.txt 1897 1898config KEXEC_JUMP 1899 bool "kexec jump" 1900 depends on KEXEC && HIBERNATION 1901 ---help--- 1902 Jump between original kernel and kexeced kernel and invoke 1903 code in physical address mode via KEXEC 1904 1905config PHYSICAL_START 1906 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1907 default "0x1000000" 1908 ---help--- 1909 This gives the physical address where the kernel is loaded. 1910 1911 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1912 bzImage will decompress itself to above physical address and 1913 run from there. Otherwise, bzImage will run from the address where 1914 it has been loaded by the boot loader and will ignore above physical 1915 address. 1916 1917 In normal kdump cases one does not have to set/change this option 1918 as now bzImage can be compiled as a completely relocatable image 1919 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1920 address. This option is mainly useful for the folks who don't want 1921 to use a bzImage for capturing the crash dump and want to use a 1922 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1923 to be specifically compiled to run from a specific memory area 1924 (normally a reserved region) and this option comes handy. 1925 1926 So if you are using bzImage for capturing the crash dump, 1927 leave the value here unchanged to 0x1000000 and set 1928 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1929 for capturing the crash dump change this value to start of 1930 the reserved region. In other words, it can be set based on 1931 the "X" value as specified in the "crashkernel=YM@XM" 1932 command line boot parameter passed to the panic-ed 1933 kernel. Please take a look at Documentation/kdump/kdump.txt 1934 for more details about crash dumps. 1935 1936 Usage of bzImage for capturing the crash dump is recommended as 1937 one does not have to build two kernels. Same kernel can be used 1938 as production kernel and capture kernel. Above option should have 1939 gone away after relocatable bzImage support is introduced. But it 1940 is present because there are users out there who continue to use 1941 vmlinux for dump capture. This option should go away down the 1942 line. 1943 1944 Don't change this unless you know what you are doing. 1945 1946config RELOCATABLE 1947 bool "Build a relocatable kernel" 1948 default y 1949 ---help--- 1950 This builds a kernel image that retains relocation information 1951 so it can be loaded someplace besides the default 1MB. 1952 The relocations tend to make the kernel binary about 10% larger, 1953 but are discarded at runtime. 1954 1955 One use is for the kexec on panic case where the recovery kernel 1956 must live at a different physical address than the primary 1957 kernel. 1958 1959 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1960 it has been loaded at and the compile time physical address 1961 (CONFIG_PHYSICAL_START) is used as the minimum location. 1962 1963config RANDOMIZE_BASE 1964 bool "Randomize the address of the kernel image (KASLR)" 1965 depends on RELOCATABLE 1966 default n 1967 ---help--- 1968 In support of Kernel Address Space Layout Randomization (KASLR), 1969 this randomizes the physical address at which the kernel image 1970 is decompressed and the virtual address where the kernel 1971 image is mapped, as a security feature that deters exploit 1972 attempts relying on knowledge of the location of kernel 1973 code internals. 1974 1975 On 64-bit, the kernel physical and virtual addresses are 1976 randomized separately. The physical address will be anywhere 1977 between 16MB and the top of physical memory (up to 64TB). The 1978 virtual address will be randomized from 16MB up to 1GB (9 bits 1979 of entropy). Note that this also reduces the memory space 1980 available to kernel modules from 1.5GB to 1GB. 1981 1982 On 32-bit, the kernel physical and virtual addresses are 1983 randomized together. They will be randomized from 16MB up to 1984 512MB (8 bits of entropy). 1985 1986 Entropy is generated using the RDRAND instruction if it is 1987 supported. If RDTSC is supported, its value is mixed into 1988 the entropy pool as well. If neither RDRAND nor RDTSC are 1989 supported, then entropy is read from the i8254 timer. The 1990 usable entropy is limited by the kernel being built using 1991 2GB addressing, and that PHYSICAL_ALIGN must be at a 1992 minimum of 2MB. As a result, only 10 bits of entropy are 1993 theoretically possible, but the implementations are further 1994 limited due to memory layouts. 1995 1996 If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot 1997 time. To enable it, boot with "kaslr" on the kernel command 1998 line (which will also disable hibernation). 1999 2000 If unsure, say N. 2001 2002# Relocation on x86 needs some additional build support 2003config X86_NEED_RELOCS 2004 def_bool y 2005 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2006 2007config PHYSICAL_ALIGN 2008 hex "Alignment value to which kernel should be aligned" 2009 default "0x200000" 2010 range 0x2000 0x1000000 if X86_32 2011 range 0x200000 0x1000000 if X86_64 2012 ---help--- 2013 This value puts the alignment restrictions on physical address 2014 where kernel is loaded and run from. Kernel is compiled for an 2015 address which meets above alignment restriction. 2016 2017 If bootloader loads the kernel at a non-aligned address and 2018 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2019 address aligned to above value and run from there. 2020 2021 If bootloader loads the kernel at a non-aligned address and 2022 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2023 load address and decompress itself to the address it has been 2024 compiled for and run from there. The address for which kernel is 2025 compiled already meets above alignment restrictions. Hence the 2026 end result is that kernel runs from a physical address meeting 2027 above alignment restrictions. 2028 2029 On 32-bit this value must be a multiple of 0x2000. On 64-bit 2030 this value must be a multiple of 0x200000. 2031 2032 Don't change this unless you know what you are doing. 2033 2034config RANDOMIZE_MEMORY 2035 bool "Randomize the kernel memory sections" 2036 depends on X86_64 2037 depends on RANDOMIZE_BASE 2038 default RANDOMIZE_BASE 2039 ---help--- 2040 Randomizes the base virtual address of kernel memory sections 2041 (physical memory mapping, vmalloc & vmemmap). This security feature 2042 makes exploits relying on predictable memory locations less reliable. 2043 2044 The order of allocations remains unchanged. Entropy is generated in 2045 the same way as RANDOMIZE_BASE. Current implementation in the optimal 2046 configuration have in average 30,000 different possible virtual 2047 addresses for each memory section. 2048 2049 If unsure, say N. 2050 2051config RANDOMIZE_MEMORY_PHYSICAL_PADDING 2052 hex "Physical memory mapping padding" if EXPERT 2053 depends on RANDOMIZE_MEMORY 2054 default "0xa" if MEMORY_HOTPLUG 2055 default "0x0" 2056 range 0x1 0x40 if MEMORY_HOTPLUG 2057 range 0x0 0x40 2058 ---help--- 2059 Define the padding in terabytes added to the existing physical 2060 memory size during kernel memory randomization. It is useful 2061 for memory hotplug support but reduces the entropy available for 2062 address randomization. 2063 2064 If unsure, leave at the default value. 2065 2066config HOTPLUG_CPU 2067 bool "Support for hot-pluggable CPUs" 2068 depends on SMP 2069 ---help--- 2070 Say Y here to allow turning CPUs off and on. CPUs can be 2071 controlled through /sys/devices/system/cpu. 2072 ( Note: power management support will enable this option 2073 automatically on SMP systems. ) 2074 Say N if you want to disable CPU hotplug. 2075 2076config BOOTPARAM_HOTPLUG_CPU0 2077 bool "Set default setting of cpu0_hotpluggable" 2078 default n 2079 depends on HOTPLUG_CPU 2080 ---help--- 2081 Set whether default state of cpu0_hotpluggable is on or off. 2082 2083 Say Y here to enable CPU0 hotplug by default. If this switch 2084 is turned on, there is no need to give cpu0_hotplug kernel 2085 parameter and the CPU0 hotplug feature is enabled by default. 2086 2087 Please note: there are two known CPU0 dependencies if you want 2088 to enable the CPU0 hotplug feature either by this switch or by 2089 cpu0_hotplug kernel parameter. 2090 2091 First, resume from hibernate or suspend always starts from CPU0. 2092 So hibernate and suspend are prevented if CPU0 is offline. 2093 2094 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2095 offline if any interrupt can not migrate out of CPU0. There may 2096 be other CPU0 dependencies. 2097 2098 Please make sure the dependencies are under your control before 2099 you enable this feature. 2100 2101 Say N if you don't want to enable CPU0 hotplug feature by default. 2102 You still can enable the CPU0 hotplug feature at boot by kernel 2103 parameter cpu0_hotplug. 2104 2105config DEBUG_HOTPLUG_CPU0 2106 def_bool n 2107 prompt "Debug CPU0 hotplug" 2108 depends on HOTPLUG_CPU 2109 ---help--- 2110 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2111 soon as possible and boots up userspace with CPU0 offlined. User 2112 can online CPU0 back after boot time. 2113 2114 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2115 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2116 compilation or giving cpu0_hotplug kernel parameter at boot. 2117 2118 If unsure, say N. 2119 2120config COMPAT_VDSO 2121 def_bool n 2122 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2123 depends on COMPAT_32 2124 ---help--- 2125 Certain buggy versions of glibc will crash if they are 2126 presented with a 32-bit vDSO that is not mapped at the address 2127 indicated in its segment table. 2128 2129 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2130 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2131 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2132 the only released version with the bug, but OpenSUSE 9 2133 contains a buggy "glibc 2.3.2". 2134 2135 The symptom of the bug is that everything crashes on startup, saying: 2136 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2137 2138 Saying Y here changes the default value of the vdso32 boot 2139 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2140 This works around the glibc bug but hurts performance. 2141 2142 If unsure, say N: if you are compiling your own kernel, you 2143 are unlikely to be using a buggy version of glibc. 2144 2145choice 2146 prompt "vsyscall table for legacy applications" 2147 depends on X86_64 2148 default LEGACY_VSYSCALL_EMULATE 2149 help 2150 Legacy user code that does not know how to find the vDSO expects 2151 to be able to issue three syscalls by calling fixed addresses in 2152 kernel space. Since this location is not randomized with ASLR, 2153 it can be used to assist security vulnerability exploitation. 2154 2155 This setting can be changed at boot time via the kernel command 2156 line parameter vsyscall=[native|emulate|none]. 2157 2158 On a system with recent enough glibc (2.14 or newer) and no 2159 static binaries, you can say None without a performance penalty 2160 to improve security. 2161 2162 If unsure, select "Emulate". 2163 2164 config LEGACY_VSYSCALL_NATIVE 2165 bool "Native" 2166 help 2167 Actual executable code is located in the fixed vsyscall 2168 address mapping, implementing time() efficiently. Since 2169 this makes the mapping executable, it can be used during 2170 security vulnerability exploitation (traditionally as 2171 ROP gadgets). This configuration is not recommended. 2172 2173 config LEGACY_VSYSCALL_EMULATE 2174 bool "Emulate" 2175 help 2176 The kernel traps and emulates calls into the fixed 2177 vsyscall address mapping. This makes the mapping 2178 non-executable, but it still contains known contents, 2179 which could be used in certain rare security vulnerability 2180 exploits. This configuration is recommended when userspace 2181 still uses the vsyscall area. 2182 2183 config LEGACY_VSYSCALL_NONE 2184 bool "None" 2185 help 2186 There will be no vsyscall mapping at all. This will 2187 eliminate any risk of ASLR bypass due to the vsyscall 2188 fixed address mapping. Attempts to use the vsyscalls 2189 will be reported to dmesg, so that either old or 2190 malicious userspace programs can be identified. 2191 2192endchoice 2193 2194config CMDLINE_BOOL 2195 bool "Built-in kernel command line" 2196 ---help--- 2197 Allow for specifying boot arguments to the kernel at 2198 build time. On some systems (e.g. embedded ones), it is 2199 necessary or convenient to provide some or all of the 2200 kernel boot arguments with the kernel itself (that is, 2201 to not rely on the boot loader to provide them.) 2202 2203 To compile command line arguments into the kernel, 2204 set this option to 'Y', then fill in the 2205 boot arguments in CONFIG_CMDLINE. 2206 2207 Systems with fully functional boot loaders (i.e. non-embedded) 2208 should leave this option set to 'N'. 2209 2210config CMDLINE 2211 string "Built-in kernel command string" 2212 depends on CMDLINE_BOOL 2213 default "" 2214 ---help--- 2215 Enter arguments here that should be compiled into the kernel 2216 image and used at boot time. If the boot loader provides a 2217 command line at boot time, it is appended to this string to 2218 form the full kernel command line, when the system boots. 2219 2220 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2221 change this behavior. 2222 2223 In most cases, the command line (whether built-in or provided 2224 by the boot loader) should specify the device for the root 2225 file system. 2226 2227config CMDLINE_OVERRIDE 2228 bool "Built-in command line overrides boot loader arguments" 2229 depends on CMDLINE_BOOL 2230 ---help--- 2231 Set this option to 'Y' to have the kernel ignore the boot loader 2232 command line, and use ONLY the built-in command line. 2233 2234 This is used to work around broken boot loaders. This should 2235 be set to 'N' under normal conditions. 2236 2237config MODIFY_LDT_SYSCALL 2238 bool "Enable the LDT (local descriptor table)" if EXPERT 2239 default y 2240 ---help--- 2241 Linux can allow user programs to install a per-process x86 2242 Local Descriptor Table (LDT) using the modify_ldt(2) system 2243 call. This is required to run 16-bit or segmented code such as 2244 DOSEMU or some Wine programs. It is also used by some very old 2245 threading libraries. 2246 2247 Enabling this feature adds a small amount of overhead to 2248 context switches and increases the low-level kernel attack 2249 surface. Disabling it removes the modify_ldt(2) system call. 2250 2251 Saying 'N' here may make sense for embedded or server kernels. 2252 2253source "kernel/livepatch/Kconfig" 2254 2255endmenu 2256 2257config ARCH_ENABLE_MEMORY_HOTPLUG 2258 def_bool y 2259 depends on X86_64 || (X86_32 && HIGHMEM) 2260 2261config ARCH_ENABLE_MEMORY_HOTREMOVE 2262 def_bool y 2263 depends on MEMORY_HOTPLUG 2264 2265config USE_PERCPU_NUMA_NODE_ID 2266 def_bool y 2267 depends on NUMA 2268 2269config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2270 def_bool y 2271 depends on X86_64 || X86_PAE 2272 2273config ARCH_ENABLE_HUGEPAGE_MIGRATION 2274 def_bool y 2275 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2276 2277menu "Power management and ACPI options" 2278 2279config ARCH_HIBERNATION_HEADER 2280 def_bool y 2281 depends on X86_64 && HIBERNATION 2282 2283source "kernel/power/Kconfig" 2284 2285source "drivers/acpi/Kconfig" 2286 2287source "drivers/sfi/Kconfig" 2288 2289config X86_APM_BOOT 2290 def_bool y 2291 depends on APM 2292 2293menuconfig APM 2294 tristate "APM (Advanced Power Management) BIOS support" 2295 depends on X86_32 && PM_SLEEP 2296 ---help--- 2297 APM is a BIOS specification for saving power using several different 2298 techniques. This is mostly useful for battery powered laptops with 2299 APM compliant BIOSes. If you say Y here, the system time will be 2300 reset after a RESUME operation, the /proc/apm device will provide 2301 battery status information, and user-space programs will receive 2302 notification of APM "events" (e.g. battery status change). 2303 2304 If you select "Y" here, you can disable actual use of the APM 2305 BIOS by passing the "apm=off" option to the kernel at boot time. 2306 2307 Note that the APM support is almost completely disabled for 2308 machines with more than one CPU. 2309 2310 In order to use APM, you will need supporting software. For location 2311 and more information, read <file:Documentation/power/apm-acpi.txt> 2312 and the Battery Powered Linux mini-HOWTO, available from 2313 <http://www.tldp.org/docs.html#howto>. 2314 2315 This driver does not spin down disk drives (see the hdparm(8) 2316 manpage ("man 8 hdparm") for that), and it doesn't turn off 2317 VESA-compliant "green" monitors. 2318 2319 This driver does not support the TI 4000M TravelMate and the ACER 2320 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2321 desktop machines also don't have compliant BIOSes, and this driver 2322 may cause those machines to panic during the boot phase. 2323 2324 Generally, if you don't have a battery in your machine, there isn't 2325 much point in using this driver and you should say N. If you get 2326 random kernel OOPSes or reboots that don't seem to be related to 2327 anything, try disabling/enabling this option (or disabling/enabling 2328 APM in your BIOS). 2329 2330 Some other things you should try when experiencing seemingly random, 2331 "weird" problems: 2332 2333 1) make sure that you have enough swap space and that it is 2334 enabled. 2335 2) pass the "no-hlt" option to the kernel 2336 3) switch on floating point emulation in the kernel and pass 2337 the "no387" option to the kernel 2338 4) pass the "floppy=nodma" option to the kernel 2339 5) pass the "mem=4M" option to the kernel (thereby disabling 2340 all but the first 4 MB of RAM) 2341 6) make sure that the CPU is not over clocked. 2342 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2343 8) disable the cache from your BIOS settings 2344 9) install a fan for the video card or exchange video RAM 2345 10) install a better fan for the CPU 2346 11) exchange RAM chips 2347 12) exchange the motherboard. 2348 2349 To compile this driver as a module, choose M here: the 2350 module will be called apm. 2351 2352if APM 2353 2354config APM_IGNORE_USER_SUSPEND 2355 bool "Ignore USER SUSPEND" 2356 ---help--- 2357 This option will ignore USER SUSPEND requests. On machines with a 2358 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2359 series notebooks, it is necessary to say Y because of a BIOS bug. 2360 2361config APM_DO_ENABLE 2362 bool "Enable PM at boot time" 2363 ---help--- 2364 Enable APM features at boot time. From page 36 of the APM BIOS 2365 specification: "When disabled, the APM BIOS does not automatically 2366 power manage devices, enter the Standby State, enter the Suspend 2367 State, or take power saving steps in response to CPU Idle calls." 2368 This driver will make CPU Idle calls when Linux is idle (unless this 2369 feature is turned off -- see "Do CPU IDLE calls", below). This 2370 should always save battery power, but more complicated APM features 2371 will be dependent on your BIOS implementation. You may need to turn 2372 this option off if your computer hangs at boot time when using APM 2373 support, or if it beeps continuously instead of suspending. Turn 2374 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2375 T400CDT. This is off by default since most machines do fine without 2376 this feature. 2377 2378config APM_CPU_IDLE 2379 depends on CPU_IDLE 2380 bool "Make CPU Idle calls when idle" 2381 ---help--- 2382 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2383 On some machines, this can activate improved power savings, such as 2384 a slowed CPU clock rate, when the machine is idle. These idle calls 2385 are made after the idle loop has run for some length of time (e.g., 2386 333 mS). On some machines, this will cause a hang at boot time or 2387 whenever the CPU becomes idle. (On machines with more than one CPU, 2388 this option does nothing.) 2389 2390config APM_DISPLAY_BLANK 2391 bool "Enable console blanking using APM" 2392 ---help--- 2393 Enable console blanking using the APM. Some laptops can use this to 2394 turn off the LCD backlight when the screen blanker of the Linux 2395 virtual console blanks the screen. Note that this is only used by 2396 the virtual console screen blanker, and won't turn off the backlight 2397 when using the X Window system. This also doesn't have anything to 2398 do with your VESA-compliant power-saving monitor. Further, this 2399 option doesn't work for all laptops -- it might not turn off your 2400 backlight at all, or it might print a lot of errors to the console, 2401 especially if you are using gpm. 2402 2403config APM_ALLOW_INTS 2404 bool "Allow interrupts during APM BIOS calls" 2405 ---help--- 2406 Normally we disable external interrupts while we are making calls to 2407 the APM BIOS as a measure to lessen the effects of a badly behaving 2408 BIOS implementation. The BIOS should reenable interrupts if it 2409 needs to. Unfortunately, some BIOSes do not -- especially those in 2410 many of the newer IBM Thinkpads. If you experience hangs when you 2411 suspend, try setting this to Y. Otherwise, say N. 2412 2413endif # APM 2414 2415source "drivers/cpufreq/Kconfig" 2416 2417source "drivers/cpuidle/Kconfig" 2418 2419source "drivers/idle/Kconfig" 2420 2421endmenu 2422 2423 2424menu "Bus options (PCI etc.)" 2425 2426config PCI 2427 bool "PCI support" 2428 default y 2429 ---help--- 2430 Find out whether you have a PCI motherboard. PCI is the name of a 2431 bus system, i.e. the way the CPU talks to the other stuff inside 2432 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2433 VESA. If you have PCI, say Y, otherwise N. 2434 2435choice 2436 prompt "PCI access mode" 2437 depends on X86_32 && PCI 2438 default PCI_GOANY 2439 ---help--- 2440 On PCI systems, the BIOS can be used to detect the PCI devices and 2441 determine their configuration. However, some old PCI motherboards 2442 have BIOS bugs and may crash if this is done. Also, some embedded 2443 PCI-based systems don't have any BIOS at all. Linux can also try to 2444 detect the PCI hardware directly without using the BIOS. 2445 2446 With this option, you can specify how Linux should detect the 2447 PCI devices. If you choose "BIOS", the BIOS will be used, 2448 if you choose "Direct", the BIOS won't be used, and if you 2449 choose "MMConfig", then PCI Express MMCONFIG will be used. 2450 If you choose "Any", the kernel will try MMCONFIG, then the 2451 direct access method and falls back to the BIOS if that doesn't 2452 work. If unsure, go with the default, which is "Any". 2453 2454config PCI_GOBIOS 2455 bool "BIOS" 2456 2457config PCI_GOMMCONFIG 2458 bool "MMConfig" 2459 2460config PCI_GODIRECT 2461 bool "Direct" 2462 2463config PCI_GOOLPC 2464 bool "OLPC XO-1" 2465 depends on OLPC 2466 2467config PCI_GOANY 2468 bool "Any" 2469 2470endchoice 2471 2472config PCI_BIOS 2473 def_bool y 2474 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2475 2476# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2477config PCI_DIRECT 2478 def_bool y 2479 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2480 2481config PCI_MMCONFIG 2482 def_bool y 2483 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2484 2485config PCI_OLPC 2486 def_bool y 2487 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2488 2489config PCI_XEN 2490 def_bool y 2491 depends on PCI && XEN 2492 select SWIOTLB_XEN 2493 2494config PCI_DOMAINS 2495 def_bool y 2496 depends on PCI 2497 2498config PCI_MMCONFIG 2499 bool "Support mmconfig PCI config space access" 2500 depends on X86_64 && PCI && ACPI 2501 2502config PCI_CNB20LE_QUIRK 2503 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2504 depends on PCI 2505 help 2506 Read the PCI windows out of the CNB20LE host bridge. This allows 2507 PCI hotplug to work on systems with the CNB20LE chipset which do 2508 not have ACPI. 2509 2510 There's no public spec for this chipset, and this functionality 2511 is known to be incomplete. 2512 2513 You should say N unless you know you need this. 2514 2515source "drivers/pci/Kconfig" 2516 2517config ISA_BUS 2518 bool "ISA-style bus support on modern systems" if EXPERT 2519 select ISA_BUS_API 2520 help 2521 Enables ISA-style drivers on modern systems. This is necessary to 2522 support PC/104 devices on X86_64 platforms. 2523 2524 If unsure, say N. 2525 2526# x86_64 have no ISA slots, but can have ISA-style DMA. 2527config ISA_DMA_API 2528 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2529 default y 2530 help 2531 Enables ISA-style DMA support for devices requiring such controllers. 2532 If unsure, say Y. 2533 2534if X86_32 2535 2536config ISA 2537 bool "ISA support" 2538 ---help--- 2539 Find out whether you have ISA slots on your motherboard. ISA is the 2540 name of a bus system, i.e. the way the CPU talks to the other stuff 2541 inside your box. Other bus systems are PCI, EISA, MicroChannel 2542 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2543 newer boards don't support it. If you have ISA, say Y, otherwise N. 2544 2545config EISA 2546 bool "EISA support" 2547 depends on ISA 2548 ---help--- 2549 The Extended Industry Standard Architecture (EISA) bus was 2550 developed as an open alternative to the IBM MicroChannel bus. 2551 2552 The EISA bus provided some of the features of the IBM MicroChannel 2553 bus while maintaining backward compatibility with cards made for 2554 the older ISA bus. The EISA bus saw limited use between 1988 and 2555 1995 when it was made obsolete by the PCI bus. 2556 2557 Say Y here if you are building a kernel for an EISA-based machine. 2558 2559 Otherwise, say N. 2560 2561source "drivers/eisa/Kconfig" 2562 2563config SCx200 2564 tristate "NatSemi SCx200 support" 2565 ---help--- 2566 This provides basic support for National Semiconductor's 2567 (now AMD's) Geode processors. The driver probes for the 2568 PCI-IDs of several on-chip devices, so its a good dependency 2569 for other scx200_* drivers. 2570 2571 If compiled as a module, the driver is named scx200. 2572 2573config SCx200HR_TIMER 2574 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2575 depends on SCx200 2576 default y 2577 ---help--- 2578 This driver provides a clocksource built upon the on-chip 2579 27MHz high-resolution timer. Its also a workaround for 2580 NSC Geode SC-1100's buggy TSC, which loses time when the 2581 processor goes idle (as is done by the scheduler). The 2582 other workaround is idle=poll boot option. 2583 2584config OLPC 2585 bool "One Laptop Per Child support" 2586 depends on !X86_PAE 2587 select GPIOLIB 2588 select OF 2589 select OF_PROMTREE 2590 select IRQ_DOMAIN 2591 ---help--- 2592 Add support for detecting the unique features of the OLPC 2593 XO hardware. 2594 2595config OLPC_XO1_PM 2596 bool "OLPC XO-1 Power Management" 2597 depends on OLPC && MFD_CS5535 && PM_SLEEP 2598 select MFD_CORE 2599 ---help--- 2600 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2601 2602config OLPC_XO1_RTC 2603 bool "OLPC XO-1 Real Time Clock" 2604 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2605 ---help--- 2606 Add support for the XO-1 real time clock, which can be used as a 2607 programmable wakeup source. 2608 2609config OLPC_XO1_SCI 2610 bool "OLPC XO-1 SCI extras" 2611 depends on OLPC && OLPC_XO1_PM 2612 depends on INPUT=y 2613 select POWER_SUPPLY 2614 select GPIO_CS5535 2615 select MFD_CORE 2616 ---help--- 2617 Add support for SCI-based features of the OLPC XO-1 laptop: 2618 - EC-driven system wakeups 2619 - Power button 2620 - Ebook switch 2621 - Lid switch 2622 - AC adapter status updates 2623 - Battery status updates 2624 2625config OLPC_XO15_SCI 2626 bool "OLPC XO-1.5 SCI extras" 2627 depends on OLPC && ACPI 2628 select POWER_SUPPLY 2629 ---help--- 2630 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2631 - EC-driven system wakeups 2632 - AC adapter status updates 2633 - Battery status updates 2634 2635config ALIX 2636 bool "PCEngines ALIX System Support (LED setup)" 2637 select GPIOLIB 2638 ---help--- 2639 This option enables system support for the PCEngines ALIX. 2640 At present this just sets up LEDs for GPIO control on 2641 ALIX2/3/6 boards. However, other system specific setup should 2642 get added here. 2643 2644 Note: You must still enable the drivers for GPIO and LED support 2645 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2646 2647 Note: You have to set alix.force=1 for boards with Award BIOS. 2648 2649config NET5501 2650 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2651 select GPIOLIB 2652 ---help--- 2653 This option enables system support for the Soekris Engineering net5501. 2654 2655config GEOS 2656 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2657 select GPIOLIB 2658 depends on DMI 2659 ---help--- 2660 This option enables system support for the Traverse Technologies GEOS. 2661 2662config TS5500 2663 bool "Technologic Systems TS-5500 platform support" 2664 depends on MELAN 2665 select CHECK_SIGNATURE 2666 select NEW_LEDS 2667 select LEDS_CLASS 2668 ---help--- 2669 This option enables system support for the Technologic Systems TS-5500. 2670 2671endif # X86_32 2672 2673config AMD_NB 2674 def_bool y 2675 depends on CPU_SUP_AMD && PCI 2676 2677source "drivers/pcmcia/Kconfig" 2678 2679config RAPIDIO 2680 tristate "RapidIO support" 2681 depends on PCI 2682 default n 2683 help 2684 If enabled this option will include drivers and the core 2685 infrastructure code to support RapidIO interconnect devices. 2686 2687source "drivers/rapidio/Kconfig" 2688 2689config X86_SYSFB 2690 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2691 help 2692 Firmwares often provide initial graphics framebuffers so the BIOS, 2693 bootloader or kernel can show basic video-output during boot for 2694 user-guidance and debugging. Historically, x86 used the VESA BIOS 2695 Extensions and EFI-framebuffers for this, which are mostly limited 2696 to x86. 2697 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2698 framebuffers so the new generic system-framebuffer drivers can be 2699 used on x86. If the framebuffer is not compatible with the generic 2700 modes, it is adverticed as fallback platform framebuffer so legacy 2701 drivers like efifb, vesafb and uvesafb can pick it up. 2702 If this option is not selected, all system framebuffers are always 2703 marked as fallback platform framebuffers as usual. 2704 2705 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2706 not be able to pick up generic system framebuffers if this option 2707 is selected. You are highly encouraged to enable simplefb as 2708 replacement if you select this option. simplefb can correctly deal 2709 with generic system framebuffers. But you should still keep vesafb 2710 and others enabled as fallback if a system framebuffer is 2711 incompatible with simplefb. 2712 2713 If unsure, say Y. 2714 2715endmenu 2716 2717 2718menu "Executable file formats / Emulations" 2719 2720source "fs/Kconfig.binfmt" 2721 2722config IA32_EMULATION 2723 bool "IA32 Emulation" 2724 depends on X86_64 2725 select ARCH_WANT_OLD_COMPAT_IPC 2726 select BINFMT_ELF 2727 select COMPAT_BINFMT_ELF 2728 select COMPAT_OLD_SIGACTION 2729 ---help--- 2730 Include code to run legacy 32-bit programs under a 2731 64-bit kernel. You should likely turn this on, unless you're 2732 100% sure that you don't have any 32-bit programs left. 2733 2734config IA32_AOUT 2735 tristate "IA32 a.out support" 2736 depends on IA32_EMULATION 2737 ---help--- 2738 Support old a.out binaries in the 32bit emulation. 2739 2740config X86_X32 2741 bool "x32 ABI for 64-bit mode" 2742 depends on X86_64 2743 ---help--- 2744 Include code to run binaries for the x32 native 32-bit ABI 2745 for 64-bit processors. An x32 process gets access to the 2746 full 64-bit register file and wide data path while leaving 2747 pointers at 32 bits for smaller memory footprint. 2748 2749 You will need a recent binutils (2.22 or later) with 2750 elf32_x86_64 support enabled to compile a kernel with this 2751 option set. 2752 2753config COMPAT_32 2754 def_bool y 2755 depends on IA32_EMULATION || X86_32 2756 select HAVE_UID16 2757 select OLD_SIGSUSPEND3 2758 2759config COMPAT 2760 def_bool y 2761 depends on IA32_EMULATION || X86_X32 2762 2763if COMPAT 2764config COMPAT_FOR_U64_ALIGNMENT 2765 def_bool y 2766 2767config SYSVIPC_COMPAT 2768 def_bool y 2769 depends on SYSVIPC 2770 2771config KEYS_COMPAT 2772 def_bool y 2773 depends on KEYS 2774endif 2775 2776endmenu 2777 2778 2779config HAVE_ATOMIC_IOMAP 2780 def_bool y 2781 depends on X86_32 2782 2783config X86_DEV_DMA_OPS 2784 bool 2785 depends on X86_64 || STA2X11 2786 2787config X86_DMA_REMAP 2788 bool 2789 depends on STA2X11 2790 2791config PMC_ATOM 2792 def_bool y 2793 depends on PCI 2794 2795source "net/Kconfig" 2796 2797source "drivers/Kconfig" 2798 2799source "drivers/firmware/Kconfig" 2800 2801source "fs/Kconfig" 2802 2803source "arch/x86/Kconfig.debug" 2804 2805source "security/Kconfig" 2806 2807source "crypto/Kconfig" 2808 2809source "arch/x86/kvm/Kconfig" 2810 2811source "lib/Kconfig" 2812