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 if (MEMORY_ISOLATION && COMPACTION) || CMA 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_DEBUG_VIRTUAL 50 select ARCH_HAS_DEVMEM_IS_ALLOWED 51 select ARCH_HAS_ELF_RANDOMIZE 52 select ARCH_HAS_FAST_MULTIPLIER 53 select ARCH_HAS_FORTIFY_SOURCE 54 select ARCH_HAS_GCOV_PROFILE_ALL 55 select ARCH_HAS_KCOV if X86_64 56 select ARCH_HAS_MMIO_FLUSH 57 select ARCH_HAS_PMEM_API if X86_64 58 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 59 select ARCH_HAS_SET_MEMORY 60 select ARCH_HAS_SG_CHAIN 61 select ARCH_HAS_STRICT_KERNEL_RWX 62 select ARCH_HAS_STRICT_MODULE_RWX 63 select ARCH_HAS_UBSAN_SANITIZE_ALL 64 select ARCH_HAS_ZONE_DEVICE if X86_64 65 select ARCH_HAVE_NMI_SAFE_CMPXCHG 66 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 67 select ARCH_MIGHT_HAVE_PC_PARPORT 68 select ARCH_MIGHT_HAVE_PC_SERIO 69 select ARCH_SUPPORTS_ATOMIC_RMW 70 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 71 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 72 select ARCH_USE_BUILTIN_BSWAP 73 select ARCH_USE_QUEUED_RWLOCKS 74 select ARCH_USE_QUEUED_SPINLOCKS 75 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 76 select ARCH_WANT_FRAME_POINTERS 77 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 78 select ARCH_WANTS_THP_SWAP if X86_64 79 select BUILDTIME_EXTABLE_SORT 80 select CLKEVT_I8253 81 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 82 select CLOCKSOURCE_WATCHDOG 83 select DCACHE_WORD_ACCESS 84 select EDAC_ATOMIC_SCRUB 85 select EDAC_SUPPORT 86 select GENERIC_CLOCKEVENTS 87 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 88 select GENERIC_CLOCKEVENTS_MIN_ADJUST 89 select GENERIC_CMOS_UPDATE 90 select GENERIC_CPU_AUTOPROBE 91 select GENERIC_EARLY_IOREMAP 92 select GENERIC_FIND_FIRST_BIT 93 select GENERIC_IOMAP 94 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 95 select GENERIC_IRQ_MIGRATION if SMP 96 select GENERIC_IRQ_PROBE 97 select GENERIC_IRQ_SHOW 98 select GENERIC_PENDING_IRQ if SMP 99 select GENERIC_SMP_IDLE_THREAD 100 select GENERIC_STRNCPY_FROM_USER 101 select GENERIC_STRNLEN_USER 102 select GENERIC_TIME_VSYSCALL 103 select HAVE_ACPI_APEI if ACPI 104 select HAVE_ACPI_APEI_NMI if ACPI 105 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 106 select HAVE_ARCH_AUDITSYSCALL 107 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 108 select HAVE_ARCH_JUMP_LABEL 109 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 110 select HAVE_ARCH_KGDB 111 select HAVE_ARCH_KMEMCHECK 112 select HAVE_ARCH_MMAP_RND_BITS if MMU 113 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 114 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 115 select HAVE_ARCH_SECCOMP_FILTER 116 select HAVE_ARCH_TRACEHOOK 117 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 118 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 119 select HAVE_ARCH_VMAP_STACK if X86_64 120 select HAVE_ARCH_WITHIN_STACK_FRAMES 121 select HAVE_CC_STACKPROTECTOR 122 select HAVE_CMPXCHG_DOUBLE 123 select HAVE_CMPXCHG_LOCAL 124 select HAVE_CONTEXT_TRACKING if X86_64 125 select HAVE_COPY_THREAD_TLS 126 select HAVE_C_RECORDMCOUNT 127 select HAVE_DEBUG_KMEMLEAK 128 select HAVE_DEBUG_STACKOVERFLOW 129 select HAVE_DMA_API_DEBUG 130 select HAVE_DMA_CONTIGUOUS 131 select HAVE_DYNAMIC_FTRACE 132 select HAVE_DYNAMIC_FTRACE_WITH_REGS 133 select HAVE_EBPF_JIT if X86_64 134 select HAVE_EFFICIENT_UNALIGNED_ACCESS 135 select HAVE_EXIT_THREAD 136 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 137 select HAVE_FTRACE_MCOUNT_RECORD 138 select HAVE_FUNCTION_GRAPH_TRACER 139 select HAVE_FUNCTION_TRACER 140 select HAVE_GCC_PLUGINS 141 select HAVE_HW_BREAKPOINT 142 select HAVE_IDE 143 select HAVE_IOREMAP_PROT 144 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 145 select HAVE_IRQ_TIME_ACCOUNTING 146 select HAVE_KERNEL_BZIP2 147 select HAVE_KERNEL_GZIP 148 select HAVE_KERNEL_LZ4 149 select HAVE_KERNEL_LZMA 150 select HAVE_KERNEL_LZO 151 select HAVE_KERNEL_XZ 152 select HAVE_KPROBES 153 select HAVE_KPROBES_ON_FTRACE 154 select HAVE_KRETPROBES 155 select HAVE_KVM 156 select HAVE_LIVEPATCH if X86_64 157 select HAVE_MEMBLOCK 158 select HAVE_MEMBLOCK_NODE_MAP 159 select HAVE_MIXED_BREAKPOINTS_REGS 160 select HAVE_MOD_ARCH_SPECIFIC 161 select HAVE_NMI 162 select HAVE_OPROFILE 163 select HAVE_OPTPROBES 164 select HAVE_PCSPKR_PLATFORM 165 select HAVE_PERF_EVENTS 166 select HAVE_PERF_EVENTS_NMI 167 select HAVE_HARDLOCKUP_DETECTOR_PERF if HAVE_PERF_EVENTS_NMI 168 select HAVE_PERF_REGS 169 select HAVE_PERF_USER_STACK_DUMP 170 select HAVE_REGS_AND_STACK_ACCESS_API 171 select HAVE_RELIABLE_STACKTRACE if X86_64 && FRAME_POINTER && STACK_VALIDATION 172 select HAVE_STACK_VALIDATION if X86_64 173 select HAVE_SYSCALL_TRACEPOINTS 174 select HAVE_UNSTABLE_SCHED_CLOCK 175 select HAVE_USER_RETURN_NOTIFIER 176 select IRQ_FORCED_THREADING 177 select PCI_LOCKLESS_CONFIG 178 select PERF_EVENTS 179 select RTC_LIB 180 select RTC_MC146818_LIB 181 select SPARSE_IRQ 182 select SRCU 183 select SYSCTL_EXCEPTION_TRACE 184 select THREAD_INFO_IN_TASK 185 select USER_STACKTRACE_SUPPORT 186 select VIRT_TO_BUS 187 select X86_FEATURE_NAMES if PROC_FS 188 189config INSTRUCTION_DECODER 190 def_bool y 191 depends on KPROBES || PERF_EVENTS || UPROBES 192 193config OUTPUT_FORMAT 194 string 195 default "elf32-i386" if X86_32 196 default "elf64-x86-64" if X86_64 197 198config ARCH_DEFCONFIG 199 string 200 default "arch/x86/configs/i386_defconfig" if X86_32 201 default "arch/x86/configs/x86_64_defconfig" if X86_64 202 203config LOCKDEP_SUPPORT 204 def_bool y 205 206config STACKTRACE_SUPPORT 207 def_bool y 208 209config MMU 210 def_bool y 211 212config ARCH_MMAP_RND_BITS_MIN 213 default 28 if 64BIT 214 default 8 215 216config ARCH_MMAP_RND_BITS_MAX 217 default 32 if 64BIT 218 default 16 219 220config ARCH_MMAP_RND_COMPAT_BITS_MIN 221 default 8 222 223config ARCH_MMAP_RND_COMPAT_BITS_MAX 224 default 16 225 226config SBUS 227 bool 228 229config NEED_DMA_MAP_STATE 230 def_bool y 231 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 232 233config NEED_SG_DMA_LENGTH 234 def_bool y 235 236config GENERIC_ISA_DMA 237 def_bool y 238 depends on ISA_DMA_API 239 240config GENERIC_BUG 241 def_bool y 242 depends on BUG 243 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 244 245config GENERIC_BUG_RELATIVE_POINTERS 246 bool 247 248config GENERIC_HWEIGHT 249 def_bool y 250 251config ARCH_MAY_HAVE_PC_FDC 252 def_bool y 253 depends on ISA_DMA_API 254 255config RWSEM_XCHGADD_ALGORITHM 256 def_bool y 257 258config GENERIC_CALIBRATE_DELAY 259 def_bool y 260 261config ARCH_HAS_CPU_RELAX 262 def_bool y 263 264config ARCH_HAS_CACHE_LINE_SIZE 265 def_bool y 266 267config HAVE_SETUP_PER_CPU_AREA 268 def_bool y 269 270config NEED_PER_CPU_EMBED_FIRST_CHUNK 271 def_bool y 272 273config NEED_PER_CPU_PAGE_FIRST_CHUNK 274 def_bool y 275 276config ARCH_HIBERNATION_POSSIBLE 277 def_bool y 278 279config ARCH_SUSPEND_POSSIBLE 280 def_bool y 281 282config ARCH_WANT_HUGE_PMD_SHARE 283 def_bool y 284 285config ARCH_WANT_GENERAL_HUGETLB 286 def_bool y 287 288config ZONE_DMA32 289 def_bool y if X86_64 290 291config AUDIT_ARCH 292 def_bool y if X86_64 293 294config ARCH_SUPPORTS_OPTIMIZED_INLINING 295 def_bool y 296 297config ARCH_SUPPORTS_DEBUG_PAGEALLOC 298 def_bool y 299 300config KASAN_SHADOW_OFFSET 301 hex 302 depends on KASAN 303 default 0xdff8000000000000 if X86_5LEVEL 304 default 0xdffffc0000000000 305 306config HAVE_INTEL_TXT 307 def_bool y 308 depends on INTEL_IOMMU && ACPI 309 310config X86_32_SMP 311 def_bool y 312 depends on X86_32 && SMP 313 314config X86_64_SMP 315 def_bool y 316 depends on X86_64 && SMP 317 318config X86_32_LAZY_GS 319 def_bool y 320 depends on X86_32 && !CC_STACKPROTECTOR 321 322config ARCH_SUPPORTS_UPROBES 323 def_bool y 324 325config FIX_EARLYCON_MEM 326 def_bool y 327 328config PGTABLE_LEVELS 329 int 330 default 4 if X86_64 331 default 3 if X86_PAE 332 default 2 333 334source "init/Kconfig" 335source "kernel/Kconfig.freezer" 336 337menu "Processor type and features" 338 339config ZONE_DMA 340 bool "DMA memory allocation support" if EXPERT 341 default y 342 help 343 DMA memory allocation support allows devices with less than 32-bit 344 addressing to allocate within the first 16MB of address space. 345 Disable if no such devices will be used. 346 347 If unsure, say Y. 348 349config SMP 350 bool "Symmetric multi-processing support" 351 ---help--- 352 This enables support for systems with more than one CPU. If you have 353 a system with only one CPU, say N. If you have a system with more 354 than one CPU, say Y. 355 356 If you say N here, the kernel will run on uni- and multiprocessor 357 machines, but will use only one CPU of a multiprocessor machine. If 358 you say Y here, the kernel will run on many, but not all, 359 uniprocessor machines. On a uniprocessor machine, the kernel 360 will run faster if you say N here. 361 362 Note that if you say Y here and choose architecture "586" or 363 "Pentium" under "Processor family", the kernel will not work on 486 364 architectures. Similarly, multiprocessor kernels for the "PPro" 365 architecture may not work on all Pentium based boards. 366 367 People using multiprocessor machines who say Y here should also say 368 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 369 Management" code will be disabled if you say Y here. 370 371 See also <file:Documentation/x86/i386/IO-APIC.txt>, 372 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 373 <http://www.tldp.org/docs.html#howto>. 374 375 If you don't know what to do here, say N. 376 377config X86_FEATURE_NAMES 378 bool "Processor feature human-readable names" if EMBEDDED 379 default y 380 ---help--- 381 This option compiles in a table of x86 feature bits and corresponding 382 names. This is required to support /proc/cpuinfo and a few kernel 383 messages. You can disable this to save space, at the expense of 384 making those few kernel messages show numeric feature bits instead. 385 386 If in doubt, say Y. 387 388config X86_FAST_FEATURE_TESTS 389 bool "Fast CPU feature tests" if EMBEDDED 390 default y 391 ---help--- 392 Some fast-paths in the kernel depend on the capabilities of the CPU. 393 Say Y here for the kernel to patch in the appropriate code at runtime 394 based on the capabilities of the CPU. The infrastructure for patching 395 code at runtime takes up some additional space; space-constrained 396 embedded systems may wish to say N here to produce smaller, slightly 397 slower code. 398 399config X86_X2APIC 400 bool "Support x2apic" 401 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 402 ---help--- 403 This enables x2apic support on CPUs that have this feature. 404 405 This allows 32-bit apic IDs (so it can support very large systems), 406 and accesses the local apic via MSRs not via mmio. 407 408 If you don't know what to do here, say N. 409 410config X86_MPPARSE 411 bool "Enable MPS table" if ACPI || SFI 412 default y 413 depends on X86_LOCAL_APIC 414 ---help--- 415 For old smp systems that do not have proper acpi support. Newer systems 416 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 417 418config X86_BIGSMP 419 bool "Support for big SMP systems with more than 8 CPUs" 420 depends on X86_32 && SMP 421 ---help--- 422 This option is needed for the systems that have more than 8 CPUs 423 424config GOLDFISH 425 def_bool y 426 depends on X86_GOLDFISH 427 428config INTEL_RDT_A 429 bool "Intel Resource Director Technology Allocation support" 430 default n 431 depends on X86 && CPU_SUP_INTEL 432 select KERNFS 433 help 434 Select to enable resource allocation which is a sub-feature of 435 Intel Resource Director Technology(RDT). More information about 436 RDT can be found in the Intel x86 Architecture Software 437 Developer Manual. 438 439 Say N if unsure. 440 441if X86_32 442config X86_EXTENDED_PLATFORM 443 bool "Support for extended (non-PC) x86 platforms" 444 default y 445 ---help--- 446 If you disable this option then the kernel will only support 447 standard PC platforms. (which covers the vast majority of 448 systems out there.) 449 450 If you enable this option then you'll be able to select support 451 for the following (non-PC) 32 bit x86 platforms: 452 Goldfish (Android emulator) 453 AMD Elan 454 RDC R-321x SoC 455 SGI 320/540 (Visual Workstation) 456 STA2X11-based (e.g. Northville) 457 Moorestown MID devices 458 459 If you have one of these systems, or if you want to build a 460 generic distribution kernel, say Y here - otherwise say N. 461endif 462 463if X86_64 464config X86_EXTENDED_PLATFORM 465 bool "Support for extended (non-PC) x86 platforms" 466 default y 467 ---help--- 468 If you disable this option then the kernel will only support 469 standard PC platforms. (which covers the vast majority of 470 systems out there.) 471 472 If you enable this option then you'll be able to select support 473 for the following (non-PC) 64 bit x86 platforms: 474 Numascale NumaChip 475 ScaleMP vSMP 476 SGI Ultraviolet 477 478 If you have one of these systems, or if you want to build a 479 generic distribution kernel, say Y here - otherwise say N. 480endif 481# This is an alphabetically sorted list of 64 bit extended platforms 482# Please maintain the alphabetic order if and when there are additions 483config X86_NUMACHIP 484 bool "Numascale NumaChip" 485 depends on X86_64 486 depends on X86_EXTENDED_PLATFORM 487 depends on NUMA 488 depends on SMP 489 depends on X86_X2APIC 490 depends on PCI_MMCONFIG 491 ---help--- 492 Adds support for Numascale NumaChip large-SMP systems. Needed to 493 enable more than ~168 cores. 494 If you don't have one of these, you should say N here. 495 496config X86_VSMP 497 bool "ScaleMP vSMP" 498 select HYPERVISOR_GUEST 499 select PARAVIRT 500 depends on X86_64 && PCI 501 depends on X86_EXTENDED_PLATFORM 502 depends on SMP 503 ---help--- 504 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 505 supposed to run on these EM64T-based machines. Only choose this option 506 if you have one of these machines. 507 508config X86_UV 509 bool "SGI Ultraviolet" 510 depends on X86_64 511 depends on X86_EXTENDED_PLATFORM 512 depends on NUMA 513 depends on EFI 514 depends on X86_X2APIC 515 depends on PCI 516 ---help--- 517 This option is needed in order to support SGI Ultraviolet systems. 518 If you don't have one of these, you should say N here. 519 520# Following is an alphabetically sorted list of 32 bit extended platforms 521# Please maintain the alphabetic order if and when there are additions 522 523config X86_GOLDFISH 524 bool "Goldfish (Virtual Platform)" 525 depends on X86_EXTENDED_PLATFORM 526 ---help--- 527 Enable support for the Goldfish virtual platform used primarily 528 for Android development. Unless you are building for the Android 529 Goldfish emulator say N here. 530 531config X86_INTEL_CE 532 bool "CE4100 TV platform" 533 depends on PCI 534 depends on PCI_GODIRECT 535 depends on X86_IO_APIC 536 depends on X86_32 537 depends on X86_EXTENDED_PLATFORM 538 select X86_REBOOTFIXUPS 539 select OF 540 select OF_EARLY_FLATTREE 541 ---help--- 542 Select for the Intel CE media processor (CE4100) SOC. 543 This option compiles in support for the CE4100 SOC for settop 544 boxes and media devices. 545 546config X86_INTEL_MID 547 bool "Intel MID platform support" 548 depends on X86_EXTENDED_PLATFORM 549 depends on X86_PLATFORM_DEVICES 550 depends on PCI 551 depends on X86_64 || (PCI_GOANY && X86_32) 552 depends on X86_IO_APIC 553 select SFI 554 select I2C 555 select DW_APB_TIMER 556 select APB_TIMER 557 select INTEL_SCU_IPC 558 select MFD_INTEL_MSIC 559 ---help--- 560 Select to build a kernel capable of supporting Intel MID (Mobile 561 Internet Device) platform systems which do not have the PCI legacy 562 interfaces. If you are building for a PC class system say N here. 563 564 Intel MID platforms are based on an Intel processor and chipset which 565 consume less power than most of the x86 derivatives. 566 567config X86_INTEL_QUARK 568 bool "Intel Quark platform support" 569 depends on X86_32 570 depends on X86_EXTENDED_PLATFORM 571 depends on X86_PLATFORM_DEVICES 572 depends on X86_TSC 573 depends on PCI 574 depends on PCI_GOANY 575 depends on X86_IO_APIC 576 select IOSF_MBI 577 select INTEL_IMR 578 select COMMON_CLK 579 ---help--- 580 Select to include support for Quark X1000 SoC. 581 Say Y here if you have a Quark based system such as the Arduino 582 compatible Intel Galileo. 583 584config X86_INTEL_LPSS 585 bool "Intel Low Power Subsystem Support" 586 depends on X86 && ACPI 587 select COMMON_CLK 588 select PINCTRL 589 select IOSF_MBI 590 ---help--- 591 Select to build support for Intel Low Power Subsystem such as 592 found on Intel Lynxpoint PCH. Selecting this option enables 593 things like clock tree (common clock framework) and pincontrol 594 which are needed by the LPSS peripheral drivers. 595 596config X86_AMD_PLATFORM_DEVICE 597 bool "AMD ACPI2Platform devices support" 598 depends on ACPI 599 select COMMON_CLK 600 select PINCTRL 601 ---help--- 602 Select to interpret AMD specific ACPI device to platform device 603 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 604 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 605 implemented under PINCTRL subsystem. 606 607config IOSF_MBI 608 tristate "Intel SoC IOSF Sideband support for SoC platforms" 609 depends on PCI 610 ---help--- 611 This option enables sideband register access support for Intel SoC 612 platforms. On these platforms the IOSF sideband is used in lieu of 613 MSR's for some register accesses, mostly but not limited to thermal 614 and power. Drivers may query the availability of this device to 615 determine if they need the sideband in order to work on these 616 platforms. The sideband is available on the following SoC products. 617 This list is not meant to be exclusive. 618 - BayTrail 619 - Braswell 620 - Quark 621 622 You should say Y if you are running a kernel on one of these SoC's. 623 624config IOSF_MBI_DEBUG 625 bool "Enable IOSF sideband access through debugfs" 626 depends on IOSF_MBI && DEBUG_FS 627 ---help--- 628 Select this option to expose the IOSF sideband access registers (MCR, 629 MDR, MCRX) through debugfs to write and read register information from 630 different units on the SoC. This is most useful for obtaining device 631 state information for debug and analysis. As this is a general access 632 mechanism, users of this option would have specific knowledge of the 633 device they want to access. 634 635 If you don't require the option or are in doubt, say N. 636 637config X86_RDC321X 638 bool "RDC R-321x SoC" 639 depends on X86_32 640 depends on X86_EXTENDED_PLATFORM 641 select M486 642 select X86_REBOOTFIXUPS 643 ---help--- 644 This option is needed for RDC R-321x system-on-chip, also known 645 as R-8610-(G). 646 If you don't have one of these chips, you should say N here. 647 648config X86_32_NON_STANDARD 649 bool "Support non-standard 32-bit SMP architectures" 650 depends on X86_32 && SMP 651 depends on X86_EXTENDED_PLATFORM 652 ---help--- 653 This option compiles in the bigsmp and STA2X11 default 654 subarchitectures. It is intended for a generic binary 655 kernel. If you select them all, kernel will probe it one by 656 one and will fallback to default. 657 658# Alphabetically sorted list of Non standard 32 bit platforms 659 660config X86_SUPPORTS_MEMORY_FAILURE 661 def_bool y 662 # MCE code calls memory_failure(): 663 depends on X86_MCE 664 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 665 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 666 depends on X86_64 || !SPARSEMEM 667 select ARCH_SUPPORTS_MEMORY_FAILURE 668 669config STA2X11 670 bool "STA2X11 Companion Chip Support" 671 depends on X86_32_NON_STANDARD && PCI 672 select X86_DEV_DMA_OPS 673 select X86_DMA_REMAP 674 select SWIOTLB 675 select MFD_STA2X11 676 select GPIOLIB 677 default n 678 ---help--- 679 This adds support for boards based on the STA2X11 IO-Hub, 680 a.k.a. "ConneXt". The chip is used in place of the standard 681 PC chipset, so all "standard" peripherals are missing. If this 682 option is selected the kernel will still be able to boot on 683 standard PC machines. 684 685config X86_32_IRIS 686 tristate "Eurobraille/Iris poweroff module" 687 depends on X86_32 688 ---help--- 689 The Iris machines from EuroBraille do not have APM or ACPI support 690 to shut themselves down properly. A special I/O sequence is 691 needed to do so, which is what this module does at 692 kernel shutdown. 693 694 This is only for Iris machines from EuroBraille. 695 696 If unused, say N. 697 698config SCHED_OMIT_FRAME_POINTER 699 def_bool y 700 prompt "Single-depth WCHAN output" 701 depends on X86 702 ---help--- 703 Calculate simpler /proc/<PID>/wchan values. If this option 704 is disabled then wchan values will recurse back to the 705 caller function. This provides more accurate wchan values, 706 at the expense of slightly more scheduling overhead. 707 708 If in doubt, say "Y". 709 710menuconfig HYPERVISOR_GUEST 711 bool "Linux guest support" 712 ---help--- 713 Say Y here to enable options for running Linux under various hyper- 714 visors. This option enables basic hypervisor detection and platform 715 setup. 716 717 If you say N, all options in this submenu will be skipped and 718 disabled, and Linux guest support won't be built in. 719 720if HYPERVISOR_GUEST 721 722config PARAVIRT 723 bool "Enable paravirtualization code" 724 ---help--- 725 This changes the kernel so it can modify itself when it is run 726 under a hypervisor, potentially improving performance significantly 727 over full virtualization. However, when run without a hypervisor 728 the kernel is theoretically slower and slightly larger. 729 730config PARAVIRT_DEBUG 731 bool "paravirt-ops debugging" 732 depends on PARAVIRT && DEBUG_KERNEL 733 ---help--- 734 Enable to debug paravirt_ops internals. Specifically, BUG if 735 a paravirt_op is missing when it is called. 736 737config PARAVIRT_SPINLOCKS 738 bool "Paravirtualization layer for spinlocks" 739 depends on PARAVIRT && SMP 740 ---help--- 741 Paravirtualized spinlocks allow a pvops backend to replace the 742 spinlock implementation with something virtualization-friendly 743 (for example, block the virtual CPU rather than spinning). 744 745 It has a minimal impact on native kernels and gives a nice performance 746 benefit on paravirtualized KVM / Xen kernels. 747 748 If you are unsure how to answer this question, answer Y. 749 750config QUEUED_LOCK_STAT 751 bool "Paravirt queued spinlock statistics" 752 depends on PARAVIRT_SPINLOCKS && DEBUG_FS 753 ---help--- 754 Enable the collection of statistical data on the slowpath 755 behavior of paravirtualized queued spinlocks and report 756 them on debugfs. 757 758source "arch/x86/xen/Kconfig" 759 760config KVM_GUEST 761 bool "KVM Guest support (including kvmclock)" 762 depends on PARAVIRT 763 select PARAVIRT_CLOCK 764 default y 765 ---help--- 766 This option enables various optimizations for running under the KVM 767 hypervisor. It includes a paravirtualized clock, so that instead 768 of relying on a PIT (or probably other) emulation by the 769 underlying device model, the host provides the guest with 770 timing infrastructure such as time of day, and system time 771 772config KVM_DEBUG_FS 773 bool "Enable debug information for KVM Guests in debugfs" 774 depends on KVM_GUEST && DEBUG_FS 775 default n 776 ---help--- 777 This option enables collection of various statistics for KVM guest. 778 Statistics are displayed in debugfs filesystem. Enabling this option 779 may incur significant overhead. 780 781source "arch/x86/lguest/Kconfig" 782 783config PARAVIRT_TIME_ACCOUNTING 784 bool "Paravirtual steal time accounting" 785 depends on PARAVIRT 786 default n 787 ---help--- 788 Select this option to enable fine granularity task steal time 789 accounting. Time spent executing other tasks in parallel with 790 the current vCPU is discounted from the vCPU power. To account for 791 that, there can be a small performance impact. 792 793 If in doubt, say N here. 794 795config PARAVIRT_CLOCK 796 bool 797 798endif #HYPERVISOR_GUEST 799 800config NO_BOOTMEM 801 def_bool y 802 803source "arch/x86/Kconfig.cpu" 804 805config HPET_TIMER 806 def_bool X86_64 807 prompt "HPET Timer Support" if X86_32 808 ---help--- 809 Use the IA-PC HPET (High Precision Event Timer) to manage 810 time in preference to the PIT and RTC, if a HPET is 811 present. 812 HPET is the next generation timer replacing legacy 8254s. 813 The HPET provides a stable time base on SMP 814 systems, unlike the TSC, but it is more expensive to access, 815 as it is off-chip. The interface used is documented 816 in the HPET spec, revision 1. 817 818 You can safely choose Y here. However, HPET will only be 819 activated if the platform and the BIOS support this feature. 820 Otherwise the 8254 will be used for timing services. 821 822 Choose N to continue using the legacy 8254 timer. 823 824config HPET_EMULATE_RTC 825 def_bool y 826 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 827 828config APB_TIMER 829 def_bool y if X86_INTEL_MID 830 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 831 select DW_APB_TIMER 832 depends on X86_INTEL_MID && SFI 833 help 834 APB timer is the replacement for 8254, HPET on X86 MID platforms. 835 The APBT provides a stable time base on SMP 836 systems, unlike the TSC, but it is more expensive to access, 837 as it is off-chip. APB timers are always running regardless of CPU 838 C states, they are used as per CPU clockevent device when possible. 839 840# Mark as expert because too many people got it wrong. 841# The code disables itself when not needed. 842config DMI 843 default y 844 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 845 bool "Enable DMI scanning" if EXPERT 846 ---help--- 847 Enabled scanning of DMI to identify machine quirks. Say Y 848 here unless you have verified that your setup is not 849 affected by entries in the DMI blacklist. Required by PNP 850 BIOS code. 851 852config GART_IOMMU 853 bool "Old AMD GART IOMMU support" 854 select SWIOTLB 855 depends on X86_64 && PCI && AMD_NB 856 ---help--- 857 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 858 GART based hardware IOMMUs. 859 860 The GART supports full DMA access for devices with 32-bit access 861 limitations, on systems with more than 3 GB. This is usually needed 862 for USB, sound, many IDE/SATA chipsets and some other devices. 863 864 Newer systems typically have a modern AMD IOMMU, supported via 865 the CONFIG_AMD_IOMMU=y config option. 866 867 In normal configurations this driver is only active when needed: 868 there's more than 3 GB of memory and the system contains a 869 32-bit limited device. 870 871 If unsure, say Y. 872 873config CALGARY_IOMMU 874 bool "IBM Calgary IOMMU support" 875 select SWIOTLB 876 depends on X86_64 && PCI 877 ---help--- 878 Support for hardware IOMMUs in IBM's xSeries x366 and x460 879 systems. Needed to run systems with more than 3GB of memory 880 properly with 32-bit PCI devices that do not support DAC 881 (Double Address Cycle). Calgary also supports bus level 882 isolation, where all DMAs pass through the IOMMU. This 883 prevents them from going anywhere except their intended 884 destination. This catches hard-to-find kernel bugs and 885 mis-behaving drivers and devices that do not use the DMA-API 886 properly to set up their DMA buffers. The IOMMU can be 887 turned off at boot time with the iommu=off parameter. 888 Normally the kernel will make the right choice by itself. 889 If unsure, say Y. 890 891config CALGARY_IOMMU_ENABLED_BY_DEFAULT 892 def_bool y 893 prompt "Should Calgary be enabled by default?" 894 depends on CALGARY_IOMMU 895 ---help--- 896 Should Calgary be enabled by default? if you choose 'y', Calgary 897 will be used (if it exists). If you choose 'n', Calgary will not be 898 used even if it exists. If you choose 'n' and would like to use 899 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 900 If unsure, say Y. 901 902# need this always selected by IOMMU for the VIA workaround 903config SWIOTLB 904 def_bool y if X86_64 905 ---help--- 906 Support for software bounce buffers used on x86-64 systems 907 which don't have a hardware IOMMU. Using this PCI devices 908 which can only access 32-bits of memory can be used on systems 909 with more than 3 GB of memory. 910 If unsure, say Y. 911 912config IOMMU_HELPER 913 def_bool y 914 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 915 916config MAXSMP 917 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 918 depends on X86_64 && SMP && DEBUG_KERNEL 919 select CPUMASK_OFFSTACK 920 ---help--- 921 Enable maximum number of CPUS and NUMA Nodes for this architecture. 922 If unsure, say N. 923 924config NR_CPUS 925 int "Maximum number of CPUs" if SMP && !MAXSMP 926 range 2 8 if SMP && X86_32 && !X86_BIGSMP 927 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 928 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 929 default "1" if !SMP 930 default "8192" if MAXSMP 931 default "32" if SMP && X86_BIGSMP 932 default "8" if SMP && X86_32 933 default "64" if SMP 934 ---help--- 935 This allows you to specify the maximum number of CPUs which this 936 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 937 supported value is 8192, otherwise the maximum value is 512. The 938 minimum value which makes sense is 2. 939 940 This is purely to save memory - each supported CPU adds 941 approximately eight kilobytes to the kernel image. 942 943config SCHED_SMT 944 bool "SMT (Hyperthreading) scheduler support" 945 depends on SMP 946 ---help--- 947 SMT scheduler support improves the CPU scheduler's decision making 948 when dealing with Intel Pentium 4 chips with HyperThreading at a 949 cost of slightly increased overhead in some places. If unsure say 950 N here. 951 952config SCHED_MC 953 def_bool y 954 prompt "Multi-core scheduler support" 955 depends on SMP 956 ---help--- 957 Multi-core scheduler support improves the CPU scheduler's decision 958 making when dealing with multi-core CPU chips at a cost of slightly 959 increased overhead in some places. If unsure say N here. 960 961config SCHED_MC_PRIO 962 bool "CPU core priorities scheduler support" 963 depends on SCHED_MC && CPU_SUP_INTEL 964 select X86_INTEL_PSTATE 965 select CPU_FREQ 966 default y 967 ---help--- 968 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 969 core ordering determined at manufacturing time, which allows 970 certain cores to reach higher turbo frequencies (when running 971 single threaded workloads) than others. 972 973 Enabling this kernel feature teaches the scheduler about 974 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 975 scheduler's CPU selection logic accordingly, so that higher 976 overall system performance can be achieved. 977 978 This feature will have no effect on CPUs without this feature. 979 980 If unsure say Y here. 981 982source "kernel/Kconfig.preempt" 983 984config UP_LATE_INIT 985 def_bool y 986 depends on !SMP && X86_LOCAL_APIC 987 988config X86_UP_APIC 989 bool "Local APIC support on uniprocessors" if !PCI_MSI 990 default PCI_MSI 991 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 992 ---help--- 993 A local APIC (Advanced Programmable Interrupt Controller) is an 994 integrated interrupt controller in the CPU. If you have a single-CPU 995 system which has a processor with a local APIC, you can say Y here to 996 enable and use it. If you say Y here even though your machine doesn't 997 have a local APIC, then the kernel will still run with no slowdown at 998 all. The local APIC supports CPU-generated self-interrupts (timer, 999 performance counters), and the NMI watchdog which detects hard 1000 lockups. 1001 1002config X86_UP_IOAPIC 1003 bool "IO-APIC support on uniprocessors" 1004 depends on X86_UP_APIC 1005 ---help--- 1006 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1007 SMP-capable replacement for PC-style interrupt controllers. Most 1008 SMP systems and many recent uniprocessor systems have one. 1009 1010 If you have a single-CPU system with an IO-APIC, you can say Y here 1011 to use it. If you say Y here even though your machine doesn't have 1012 an IO-APIC, then the kernel will still run with no slowdown at all. 1013 1014config X86_LOCAL_APIC 1015 def_bool y 1016 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1017 select IRQ_DOMAIN_HIERARCHY 1018 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1019 1020config X86_IO_APIC 1021 def_bool y 1022 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1023 1024config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 1025 bool "Reroute for broken boot IRQs" 1026 depends on X86_IO_APIC 1027 ---help--- 1028 This option enables a workaround that fixes a source of 1029 spurious interrupts. This is recommended when threaded 1030 interrupt handling is used on systems where the generation of 1031 superfluous "boot interrupts" cannot be disabled. 1032 1033 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 1034 entry in the chipset's IO-APIC is masked (as, e.g. the RT 1035 kernel does during interrupt handling). On chipsets where this 1036 boot IRQ generation cannot be disabled, this workaround keeps 1037 the original IRQ line masked so that only the equivalent "boot 1038 IRQ" is delivered to the CPUs. The workaround also tells the 1039 kernel to set up the IRQ handler on the boot IRQ line. In this 1040 way only one interrupt is delivered to the kernel. Otherwise 1041 the spurious second interrupt may cause the kernel to bring 1042 down (vital) interrupt lines. 1043 1044 Only affects "broken" chipsets. Interrupt sharing may be 1045 increased on these systems. 1046 1047config X86_MCE 1048 bool "Machine Check / overheating reporting" 1049 select GENERIC_ALLOCATOR 1050 default y 1051 ---help--- 1052 Machine Check support allows the processor to notify the 1053 kernel if it detects a problem (e.g. overheating, data corruption). 1054 The action the kernel takes depends on the severity of the problem, 1055 ranging from warning messages to halting the machine. 1056 1057config X86_MCELOG_LEGACY 1058 bool "Support for deprecated /dev/mcelog character device" 1059 depends on X86_MCE 1060 ---help--- 1061 Enable support for /dev/mcelog which is needed by the old mcelog 1062 userspace logging daemon. Consider switching to the new generation 1063 rasdaemon solution. 1064 1065config X86_MCE_INTEL 1066 def_bool y 1067 prompt "Intel MCE features" 1068 depends on X86_MCE && X86_LOCAL_APIC 1069 ---help--- 1070 Additional support for intel specific MCE features such as 1071 the thermal monitor. 1072 1073config X86_MCE_AMD 1074 def_bool y 1075 prompt "AMD MCE features" 1076 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 1077 ---help--- 1078 Additional support for AMD specific MCE features such as 1079 the DRAM Error Threshold. 1080 1081config X86_ANCIENT_MCE 1082 bool "Support for old Pentium 5 / WinChip machine checks" 1083 depends on X86_32 && X86_MCE 1084 ---help--- 1085 Include support for machine check handling on old Pentium 5 or WinChip 1086 systems. These typically need to be enabled explicitly on the command 1087 line. 1088 1089config X86_MCE_THRESHOLD 1090 depends on X86_MCE_AMD || X86_MCE_INTEL 1091 def_bool y 1092 1093config X86_MCE_INJECT 1094 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1095 tristate "Machine check injector support" 1096 ---help--- 1097 Provide support for injecting machine checks for testing purposes. 1098 If you don't know what a machine check is and you don't do kernel 1099 QA it is safe to say n. 1100 1101config X86_THERMAL_VECTOR 1102 def_bool y 1103 depends on X86_MCE_INTEL 1104 1105source "arch/x86/events/Kconfig" 1106 1107config X86_LEGACY_VM86 1108 bool "Legacy VM86 support" 1109 default n 1110 depends on X86_32 1111 ---help--- 1112 This option allows user programs to put the CPU into V8086 1113 mode, which is an 80286-era approximation of 16-bit real mode. 1114 1115 Some very old versions of X and/or vbetool require this option 1116 for user mode setting. Similarly, DOSEMU will use it if 1117 available to accelerate real mode DOS programs. However, any 1118 recent version of DOSEMU, X, or vbetool should be fully 1119 functional even without kernel VM86 support, as they will all 1120 fall back to software emulation. Nevertheless, if you are using 1121 a 16-bit DOS program where 16-bit performance matters, vm86 1122 mode might be faster than emulation and you might want to 1123 enable this option. 1124 1125 Note that any app that works on a 64-bit kernel is unlikely to 1126 need this option, as 64-bit kernels don't, and can't, support 1127 V8086 mode. This option is also unrelated to 16-bit protected 1128 mode and is not needed to run most 16-bit programs under Wine. 1129 1130 Enabling this option increases the complexity of the kernel 1131 and slows down exception handling a tiny bit. 1132 1133 If unsure, say N here. 1134 1135config VM86 1136 bool 1137 default X86_LEGACY_VM86 1138 1139config X86_16BIT 1140 bool "Enable support for 16-bit segments" if EXPERT 1141 default y 1142 depends on MODIFY_LDT_SYSCALL 1143 ---help--- 1144 This option is required by programs like Wine to run 16-bit 1145 protected mode legacy code on x86 processors. Disabling 1146 this option saves about 300 bytes on i386, or around 6K text 1147 plus 16K runtime memory on x86-64, 1148 1149config X86_ESPFIX32 1150 def_bool y 1151 depends on X86_16BIT && X86_32 1152 1153config X86_ESPFIX64 1154 def_bool y 1155 depends on X86_16BIT && X86_64 1156 1157config X86_VSYSCALL_EMULATION 1158 bool "Enable vsyscall emulation" if EXPERT 1159 default y 1160 depends on X86_64 1161 ---help--- 1162 This enables emulation of the legacy vsyscall page. Disabling 1163 it is roughly equivalent to booting with vsyscall=none, except 1164 that it will also disable the helpful warning if a program 1165 tries to use a vsyscall. With this option set to N, offending 1166 programs will just segfault, citing addresses of the form 1167 0xffffffffff600?00. 1168 1169 This option is required by many programs built before 2013, and 1170 care should be used even with newer programs if set to N. 1171 1172 Disabling this option saves about 7K of kernel size and 1173 possibly 4K of additional runtime pagetable memory. 1174 1175config TOSHIBA 1176 tristate "Toshiba Laptop support" 1177 depends on X86_32 1178 ---help--- 1179 This adds a driver to safely access the System Management Mode of 1180 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1181 not work on models with a Phoenix BIOS. The System Management Mode 1182 is used to set the BIOS and power saving options on Toshiba portables. 1183 1184 For information on utilities to make use of this driver see the 1185 Toshiba Linux utilities web site at: 1186 <http://www.buzzard.org.uk/toshiba/>. 1187 1188 Say Y if you intend to run this kernel on a Toshiba portable. 1189 Say N otherwise. 1190 1191config I8K 1192 tristate "Dell i8k legacy laptop support" 1193 select HWMON 1194 select SENSORS_DELL_SMM 1195 ---help--- 1196 This option enables legacy /proc/i8k userspace interface in hwmon 1197 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1198 temperature and allows controlling fan speeds of Dell laptops via 1199 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1200 it reports also power and hotkey status. For fan speed control is 1201 needed userspace package i8kutils. 1202 1203 Say Y if you intend to run this kernel on old Dell laptops or want to 1204 use userspace package i8kutils. 1205 Say N otherwise. 1206 1207config X86_REBOOTFIXUPS 1208 bool "Enable X86 board specific fixups for reboot" 1209 depends on X86_32 1210 ---help--- 1211 This enables chipset and/or board specific fixups to be done 1212 in order to get reboot to work correctly. This is only needed on 1213 some combinations of hardware and BIOS. The symptom, for which 1214 this config is intended, is when reboot ends with a stalled/hung 1215 system. 1216 1217 Currently, the only fixup is for the Geode machines using 1218 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1219 1220 Say Y if you want to enable the fixup. Currently, it's safe to 1221 enable this option even if you don't need it. 1222 Say N otherwise. 1223 1224config MICROCODE 1225 bool "CPU microcode loading support" 1226 default y 1227 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1228 select FW_LOADER 1229 ---help--- 1230 If you say Y here, you will be able to update the microcode on 1231 Intel and AMD processors. The Intel support is for the IA32 family, 1232 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1233 AMD support is for families 0x10 and later. You will obviously need 1234 the actual microcode binary data itself which is not shipped with 1235 the Linux kernel. 1236 1237 The preferred method to load microcode from a detached initrd is described 1238 in Documentation/x86/early-microcode.txt. For that you need to enable 1239 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1240 initrd for microcode blobs. 1241 1242 In addition, you can build-in the microcode into the kernel. For that you 1243 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 1244 to the CONFIG_EXTRA_FIRMWARE config option. 1245 1246config MICROCODE_INTEL 1247 bool "Intel microcode loading support" 1248 depends on MICROCODE 1249 default MICROCODE 1250 select FW_LOADER 1251 ---help--- 1252 This options enables microcode patch loading support for Intel 1253 processors. 1254 1255 For the current Intel microcode data package go to 1256 <https://downloadcenter.intel.com> and search for 1257 'Linux Processor Microcode Data File'. 1258 1259config MICROCODE_AMD 1260 bool "AMD microcode loading support" 1261 depends on MICROCODE 1262 select FW_LOADER 1263 ---help--- 1264 If you select this option, microcode patch loading support for AMD 1265 processors will be enabled. 1266 1267config MICROCODE_OLD_INTERFACE 1268 def_bool y 1269 depends on MICROCODE 1270 1271config X86_MSR 1272 tristate "/dev/cpu/*/msr - Model-specific register support" 1273 ---help--- 1274 This device gives privileged processes access to the x86 1275 Model-Specific Registers (MSRs). It is a character device with 1276 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1277 MSR accesses are directed to a specific CPU on multi-processor 1278 systems. 1279 1280config X86_CPUID 1281 tristate "/dev/cpu/*/cpuid - CPU information support" 1282 ---help--- 1283 This device gives processes access to the x86 CPUID instruction to 1284 be executed on a specific processor. It is a character device 1285 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1286 /dev/cpu/31/cpuid. 1287 1288choice 1289 prompt "High Memory Support" 1290 default HIGHMEM4G 1291 depends on X86_32 1292 1293config NOHIGHMEM 1294 bool "off" 1295 ---help--- 1296 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1297 However, the address space of 32-bit x86 processors is only 4 1298 Gigabytes large. That means that, if you have a large amount of 1299 physical memory, not all of it can be "permanently mapped" by the 1300 kernel. The physical memory that's not permanently mapped is called 1301 "high memory". 1302 1303 If you are compiling a kernel which will never run on a machine with 1304 more than 1 Gigabyte total physical RAM, answer "off" here (default 1305 choice and suitable for most users). This will result in a "3GB/1GB" 1306 split: 3GB are mapped so that each process sees a 3GB virtual memory 1307 space and the remaining part of the 4GB virtual memory space is used 1308 by the kernel to permanently map as much physical memory as 1309 possible. 1310 1311 If the machine has between 1 and 4 Gigabytes physical RAM, then 1312 answer "4GB" here. 1313 1314 If more than 4 Gigabytes is used then answer "64GB" here. This 1315 selection turns Intel PAE (Physical Address Extension) mode on. 1316 PAE implements 3-level paging on IA32 processors. PAE is fully 1317 supported by Linux, PAE mode is implemented on all recent Intel 1318 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1319 then the kernel will not boot on CPUs that don't support PAE! 1320 1321 The actual amount of total physical memory will either be 1322 auto detected or can be forced by using a kernel command line option 1323 such as "mem=256M". (Try "man bootparam" or see the documentation of 1324 your boot loader (lilo or loadlin) about how to pass options to the 1325 kernel at boot time.) 1326 1327 If unsure, say "off". 1328 1329config HIGHMEM4G 1330 bool "4GB" 1331 ---help--- 1332 Select this if you have a 32-bit processor and between 1 and 4 1333 gigabytes of physical RAM. 1334 1335config HIGHMEM64G 1336 bool "64GB" 1337 depends on !M486 1338 select X86_PAE 1339 ---help--- 1340 Select this if you have a 32-bit processor and more than 4 1341 gigabytes of physical RAM. 1342 1343endchoice 1344 1345choice 1346 prompt "Memory split" if EXPERT 1347 default VMSPLIT_3G 1348 depends on X86_32 1349 ---help--- 1350 Select the desired split between kernel and user memory. 1351 1352 If the address range available to the kernel is less than the 1353 physical memory installed, the remaining memory will be available 1354 as "high memory". Accessing high memory is a little more costly 1355 than low memory, as it needs to be mapped into the kernel first. 1356 Note that increasing the kernel address space limits the range 1357 available to user programs, making the address space there 1358 tighter. Selecting anything other than the default 3G/1G split 1359 will also likely make your kernel incompatible with binary-only 1360 kernel modules. 1361 1362 If you are not absolutely sure what you are doing, leave this 1363 option alone! 1364 1365 config VMSPLIT_3G 1366 bool "3G/1G user/kernel split" 1367 config VMSPLIT_3G_OPT 1368 depends on !X86_PAE 1369 bool "3G/1G user/kernel split (for full 1G low memory)" 1370 config VMSPLIT_2G 1371 bool "2G/2G user/kernel split" 1372 config VMSPLIT_2G_OPT 1373 depends on !X86_PAE 1374 bool "2G/2G user/kernel split (for full 2G low memory)" 1375 config VMSPLIT_1G 1376 bool "1G/3G user/kernel split" 1377endchoice 1378 1379config PAGE_OFFSET 1380 hex 1381 default 0xB0000000 if VMSPLIT_3G_OPT 1382 default 0x80000000 if VMSPLIT_2G 1383 default 0x78000000 if VMSPLIT_2G_OPT 1384 default 0x40000000 if VMSPLIT_1G 1385 default 0xC0000000 1386 depends on X86_32 1387 1388config HIGHMEM 1389 def_bool y 1390 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1391 1392config X86_PAE 1393 bool "PAE (Physical Address Extension) Support" 1394 depends on X86_32 && !HIGHMEM4G 1395 select SWIOTLB 1396 ---help--- 1397 PAE is required for NX support, and furthermore enables 1398 larger swapspace support for non-overcommit purposes. It 1399 has the cost of more pagetable lookup overhead, and also 1400 consumes more pagetable space per process. 1401 1402config ARCH_PHYS_ADDR_T_64BIT 1403 def_bool y 1404 depends on X86_64 || X86_PAE 1405 1406config ARCH_DMA_ADDR_T_64BIT 1407 def_bool y 1408 depends on X86_64 || HIGHMEM64G 1409 1410config X86_DIRECT_GBPAGES 1411 def_bool y 1412 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1413 ---help--- 1414 Certain kernel features effectively disable kernel 1415 linear 1 GB mappings (even if the CPU otherwise 1416 supports them), so don't confuse the user by printing 1417 that we have them enabled. 1418 1419# Common NUMA Features 1420config NUMA 1421 bool "Numa Memory Allocation and Scheduler Support" 1422 depends on SMP 1423 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1424 default y if X86_BIGSMP 1425 ---help--- 1426 Enable NUMA (Non Uniform Memory Access) support. 1427 1428 The kernel will try to allocate memory used by a CPU on the 1429 local memory controller of the CPU and add some more 1430 NUMA awareness to the kernel. 1431 1432 For 64-bit this is recommended if the system is Intel Core i7 1433 (or later), AMD Opteron, or EM64T NUMA. 1434 1435 For 32-bit this is only needed if you boot a 32-bit 1436 kernel on a 64-bit NUMA platform. 1437 1438 Otherwise, you should say N. 1439 1440config AMD_NUMA 1441 def_bool y 1442 prompt "Old style AMD Opteron NUMA detection" 1443 depends on X86_64 && NUMA && PCI 1444 ---help--- 1445 Enable AMD NUMA node topology detection. You should say Y here if 1446 you have a multi processor AMD system. This uses an old method to 1447 read the NUMA configuration directly from the builtin Northbridge 1448 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1449 which also takes priority if both are compiled in. 1450 1451config X86_64_ACPI_NUMA 1452 def_bool y 1453 prompt "ACPI NUMA detection" 1454 depends on X86_64 && NUMA && ACPI && PCI 1455 select ACPI_NUMA 1456 ---help--- 1457 Enable ACPI SRAT based node topology detection. 1458 1459# Some NUMA nodes have memory ranges that span 1460# other nodes. Even though a pfn is valid and 1461# between a node's start and end pfns, it may not 1462# reside on that node. See memmap_init_zone() 1463# for details. 1464config NODES_SPAN_OTHER_NODES 1465 def_bool y 1466 depends on X86_64_ACPI_NUMA 1467 1468config NUMA_EMU 1469 bool "NUMA emulation" 1470 depends on NUMA 1471 ---help--- 1472 Enable NUMA emulation. A flat machine will be split 1473 into virtual nodes when booted with "numa=fake=N", where N is the 1474 number of nodes. This is only useful for debugging. 1475 1476config NODES_SHIFT 1477 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1478 range 1 10 1479 default "10" if MAXSMP 1480 default "6" if X86_64 1481 default "3" 1482 depends on NEED_MULTIPLE_NODES 1483 ---help--- 1484 Specify the maximum number of NUMA Nodes available on the target 1485 system. Increases memory reserved to accommodate various tables. 1486 1487config ARCH_HAVE_MEMORY_PRESENT 1488 def_bool y 1489 depends on X86_32 && DISCONTIGMEM 1490 1491config NEED_NODE_MEMMAP_SIZE 1492 def_bool y 1493 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1494 1495config ARCH_FLATMEM_ENABLE 1496 def_bool y 1497 depends on X86_32 && !NUMA 1498 1499config ARCH_DISCONTIGMEM_ENABLE 1500 def_bool y 1501 depends on NUMA && X86_32 1502 1503config ARCH_DISCONTIGMEM_DEFAULT 1504 def_bool y 1505 depends on NUMA && X86_32 1506 1507config ARCH_SPARSEMEM_ENABLE 1508 def_bool y 1509 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1510 select SPARSEMEM_STATIC if X86_32 1511 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1512 1513config ARCH_SPARSEMEM_DEFAULT 1514 def_bool y 1515 depends on X86_64 1516 1517config ARCH_SELECT_MEMORY_MODEL 1518 def_bool y 1519 depends on ARCH_SPARSEMEM_ENABLE 1520 1521config ARCH_MEMORY_PROBE 1522 bool "Enable sysfs memory/probe interface" 1523 depends on X86_64 && MEMORY_HOTPLUG 1524 help 1525 This option enables a sysfs memory/probe interface for testing. 1526 See Documentation/memory-hotplug.txt for more information. 1527 If you are unsure how to answer this question, answer N. 1528 1529config ARCH_PROC_KCORE_TEXT 1530 def_bool y 1531 depends on X86_64 && PROC_KCORE 1532 1533config ILLEGAL_POINTER_VALUE 1534 hex 1535 default 0 if X86_32 1536 default 0xdead000000000000 if X86_64 1537 1538source "mm/Kconfig" 1539 1540config X86_PMEM_LEGACY_DEVICE 1541 bool 1542 1543config X86_PMEM_LEGACY 1544 tristate "Support non-standard NVDIMMs and ADR protected memory" 1545 depends on PHYS_ADDR_T_64BIT 1546 depends on BLK_DEV 1547 select X86_PMEM_LEGACY_DEVICE 1548 select LIBNVDIMM 1549 help 1550 Treat memory marked using the non-standard e820 type of 12 as used 1551 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1552 The kernel will offer these regions to the 'pmem' driver so 1553 they can be used for persistent storage. 1554 1555 Say Y if unsure. 1556 1557config HIGHPTE 1558 bool "Allocate 3rd-level pagetables from highmem" 1559 depends on HIGHMEM 1560 ---help--- 1561 The VM uses one page table entry for each page of physical memory. 1562 For systems with a lot of RAM, this can be wasteful of precious 1563 low memory. Setting this option will put user-space page table 1564 entries in high memory. 1565 1566config X86_CHECK_BIOS_CORRUPTION 1567 bool "Check for low memory corruption" 1568 ---help--- 1569 Periodically check for memory corruption in low memory, which 1570 is suspected to be caused by BIOS. Even when enabled in the 1571 configuration, it is disabled at runtime. Enable it by 1572 setting "memory_corruption_check=1" on the kernel command 1573 line. By default it scans the low 64k of memory every 60 1574 seconds; see the memory_corruption_check_size and 1575 memory_corruption_check_period parameters in 1576 Documentation/admin-guide/kernel-parameters.rst to adjust this. 1577 1578 When enabled with the default parameters, this option has 1579 almost no overhead, as it reserves a relatively small amount 1580 of memory and scans it infrequently. It both detects corruption 1581 and prevents it from affecting the running system. 1582 1583 It is, however, intended as a diagnostic tool; if repeatable 1584 BIOS-originated corruption always affects the same memory, 1585 you can use memmap= to prevent the kernel from using that 1586 memory. 1587 1588config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1589 bool "Set the default setting of memory_corruption_check" 1590 depends on X86_CHECK_BIOS_CORRUPTION 1591 default y 1592 ---help--- 1593 Set whether the default state of memory_corruption_check is 1594 on or off. 1595 1596config X86_RESERVE_LOW 1597 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1598 default 64 1599 range 4 640 1600 ---help--- 1601 Specify the amount of low memory to reserve for the BIOS. 1602 1603 The first page contains BIOS data structures that the kernel 1604 must not use, so that page must always be reserved. 1605 1606 By default we reserve the first 64K of physical RAM, as a 1607 number of BIOSes are known to corrupt that memory range 1608 during events such as suspend/resume or monitor cable 1609 insertion, so it must not be used by the kernel. 1610 1611 You can set this to 4 if you are absolutely sure that you 1612 trust the BIOS to get all its memory reservations and usages 1613 right. If you know your BIOS have problems beyond the 1614 default 64K area, you can set this to 640 to avoid using the 1615 entire low memory range. 1616 1617 If you have doubts about the BIOS (e.g. suspend/resume does 1618 not work or there's kernel crashes after certain hardware 1619 hotplug events) then you might want to enable 1620 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1621 typical corruption patterns. 1622 1623 Leave this to the default value of 64 if you are unsure. 1624 1625config MATH_EMULATION 1626 bool 1627 depends on MODIFY_LDT_SYSCALL 1628 prompt "Math emulation" if X86_32 1629 ---help--- 1630 Linux can emulate a math coprocessor (used for floating point 1631 operations) if you don't have one. 486DX and Pentium processors have 1632 a math coprocessor built in, 486SX and 386 do not, unless you added 1633 a 487DX or 387, respectively. (The messages during boot time can 1634 give you some hints here ["man dmesg"].) Everyone needs either a 1635 coprocessor or this emulation. 1636 1637 If you don't have a math coprocessor, you need to say Y here; if you 1638 say Y here even though you have a coprocessor, the coprocessor will 1639 be used nevertheless. (This behavior can be changed with the kernel 1640 command line option "no387", which comes handy if your coprocessor 1641 is broken. Try "man bootparam" or see the documentation of your boot 1642 loader (lilo or loadlin) about how to pass options to the kernel at 1643 boot time.) This means that it is a good idea to say Y here if you 1644 intend to use this kernel on different machines. 1645 1646 More information about the internals of the Linux math coprocessor 1647 emulation can be found in <file:arch/x86/math-emu/README>. 1648 1649 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1650 kernel, it won't hurt. 1651 1652config MTRR 1653 def_bool y 1654 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1655 ---help--- 1656 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1657 the Memory Type Range Registers (MTRRs) may be used to control 1658 processor access to memory ranges. This is most useful if you have 1659 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1660 allows bus write transfers to be combined into a larger transfer 1661 before bursting over the PCI/AGP bus. This can increase performance 1662 of image write operations 2.5 times or more. Saying Y here creates a 1663 /proc/mtrr file which may be used to manipulate your processor's 1664 MTRRs. Typically the X server should use this. 1665 1666 This code has a reasonably generic interface so that similar 1667 control registers on other processors can be easily supported 1668 as well: 1669 1670 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1671 Registers (ARRs) which provide a similar functionality to MTRRs. For 1672 these, the ARRs are used to emulate the MTRRs. 1673 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1674 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1675 write-combining. All of these processors are supported by this code 1676 and it makes sense to say Y here if you have one of them. 1677 1678 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1679 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1680 can lead to all sorts of problems, so it's good to say Y here. 1681 1682 You can safely say Y even if your machine doesn't have MTRRs, you'll 1683 just add about 9 KB to your kernel. 1684 1685 See <file:Documentation/x86/mtrr.txt> for more information. 1686 1687config MTRR_SANITIZER 1688 def_bool y 1689 prompt "MTRR cleanup support" 1690 depends on MTRR 1691 ---help--- 1692 Convert MTRR layout from continuous to discrete, so X drivers can 1693 add writeback entries. 1694 1695 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1696 The largest mtrr entry size for a continuous block can be set with 1697 mtrr_chunk_size. 1698 1699 If unsure, say Y. 1700 1701config MTRR_SANITIZER_ENABLE_DEFAULT 1702 int "MTRR cleanup enable value (0-1)" 1703 range 0 1 1704 default "0" 1705 depends on MTRR_SANITIZER 1706 ---help--- 1707 Enable mtrr cleanup default value 1708 1709config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1710 int "MTRR cleanup spare reg num (0-7)" 1711 range 0 7 1712 default "1" 1713 depends on MTRR_SANITIZER 1714 ---help--- 1715 mtrr cleanup spare entries default, it can be changed via 1716 mtrr_spare_reg_nr=N on the kernel command line. 1717 1718config X86_PAT 1719 def_bool y 1720 prompt "x86 PAT support" if EXPERT 1721 depends on MTRR 1722 ---help--- 1723 Use PAT attributes to setup page level cache control. 1724 1725 PATs are the modern equivalents of MTRRs and are much more 1726 flexible than MTRRs. 1727 1728 Say N here if you see bootup problems (boot crash, boot hang, 1729 spontaneous reboots) or a non-working video driver. 1730 1731 If unsure, say Y. 1732 1733config ARCH_USES_PG_UNCACHED 1734 def_bool y 1735 depends on X86_PAT 1736 1737config ARCH_RANDOM 1738 def_bool y 1739 prompt "x86 architectural random number generator" if EXPERT 1740 ---help--- 1741 Enable the x86 architectural RDRAND instruction 1742 (Intel Bull Mountain technology) to generate random numbers. 1743 If supported, this is a high bandwidth, cryptographically 1744 secure hardware random number generator. 1745 1746config X86_SMAP 1747 def_bool y 1748 prompt "Supervisor Mode Access Prevention" if EXPERT 1749 ---help--- 1750 Supervisor Mode Access Prevention (SMAP) is a security 1751 feature in newer Intel processors. There is a small 1752 performance cost if this enabled and turned on; there is 1753 also a small increase in the kernel size if this is enabled. 1754 1755 If unsure, say Y. 1756 1757config X86_INTEL_MPX 1758 prompt "Intel MPX (Memory Protection Extensions)" 1759 def_bool n 1760 depends on CPU_SUP_INTEL 1761 ---help--- 1762 MPX provides hardware features that can be used in 1763 conjunction with compiler-instrumented code to check 1764 memory references. It is designed to detect buffer 1765 overflow or underflow bugs. 1766 1767 This option enables running applications which are 1768 instrumented or otherwise use MPX. It does not use MPX 1769 itself inside the kernel or to protect the kernel 1770 against bad memory references. 1771 1772 Enabling this option will make the kernel larger: 1773 ~8k of kernel text and 36 bytes of data on a 64-bit 1774 defconfig. It adds a long to the 'mm_struct' which 1775 will increase the kernel memory overhead of each 1776 process and adds some branches to paths used during 1777 exec() and munmap(). 1778 1779 For details, see Documentation/x86/intel_mpx.txt 1780 1781 If unsure, say N. 1782 1783config X86_INTEL_MEMORY_PROTECTION_KEYS 1784 prompt "Intel Memory Protection Keys" 1785 def_bool y 1786 # Note: only available in 64-bit mode 1787 depends on CPU_SUP_INTEL && X86_64 1788 select ARCH_USES_HIGH_VMA_FLAGS 1789 select ARCH_HAS_PKEYS 1790 ---help--- 1791 Memory Protection Keys provides a mechanism for enforcing 1792 page-based protections, but without requiring modification of the 1793 page tables when an application changes protection domains. 1794 1795 For details, see Documentation/x86/protection-keys.txt 1796 1797 If unsure, say y. 1798 1799config EFI 1800 bool "EFI runtime service support" 1801 depends on ACPI 1802 select UCS2_STRING 1803 select EFI_RUNTIME_WRAPPERS 1804 ---help--- 1805 This enables the kernel to use EFI runtime services that are 1806 available (such as the EFI variable services). 1807 1808 This option is only useful on systems that have EFI firmware. 1809 In addition, you should use the latest ELILO loader available 1810 at <http://elilo.sourceforge.net> in order to take advantage 1811 of EFI runtime services. However, even with this option, the 1812 resultant kernel should continue to boot on existing non-EFI 1813 platforms. 1814 1815config EFI_STUB 1816 bool "EFI stub support" 1817 depends on EFI && !X86_USE_3DNOW 1818 select RELOCATABLE 1819 ---help--- 1820 This kernel feature allows a bzImage to be loaded directly 1821 by EFI firmware without the use of a bootloader. 1822 1823 See Documentation/efi-stub.txt for more information. 1824 1825config EFI_MIXED 1826 bool "EFI mixed-mode support" 1827 depends on EFI_STUB && X86_64 1828 ---help--- 1829 Enabling this feature allows a 64-bit kernel to be booted 1830 on a 32-bit firmware, provided that your CPU supports 64-bit 1831 mode. 1832 1833 Note that it is not possible to boot a mixed-mode enabled 1834 kernel via the EFI boot stub - a bootloader that supports 1835 the EFI handover protocol must be used. 1836 1837 If unsure, say N. 1838 1839config SECCOMP 1840 def_bool y 1841 prompt "Enable seccomp to safely compute untrusted bytecode" 1842 ---help--- 1843 This kernel feature is useful for number crunching applications 1844 that may need to compute untrusted bytecode during their 1845 execution. By using pipes or other transports made available to 1846 the process as file descriptors supporting the read/write 1847 syscalls, it's possible to isolate those applications in 1848 their own address space using seccomp. Once seccomp is 1849 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1850 and the task is only allowed to execute a few safe syscalls 1851 defined by each seccomp mode. 1852 1853 If unsure, say Y. Only embedded should say N here. 1854 1855source kernel/Kconfig.hz 1856 1857config KEXEC 1858 bool "kexec system call" 1859 select KEXEC_CORE 1860 ---help--- 1861 kexec is a system call that implements the ability to shutdown your 1862 current kernel, and to start another kernel. It is like a reboot 1863 but it is independent of the system firmware. And like a reboot 1864 you can start any kernel with it, not just Linux. 1865 1866 The name comes from the similarity to the exec system call. 1867 1868 It is an ongoing process to be certain the hardware in a machine 1869 is properly shutdown, so do not be surprised if this code does not 1870 initially work for you. As of this writing the exact hardware 1871 interface is strongly in flux, so no good recommendation can be 1872 made. 1873 1874config KEXEC_FILE 1875 bool "kexec file based system call" 1876 select KEXEC_CORE 1877 select BUILD_BIN2C 1878 depends on X86_64 1879 depends on CRYPTO=y 1880 depends on CRYPTO_SHA256=y 1881 ---help--- 1882 This is new version of kexec system call. This system call is 1883 file based and takes file descriptors as system call argument 1884 for kernel and initramfs as opposed to list of segments as 1885 accepted by previous system call. 1886 1887config KEXEC_VERIFY_SIG 1888 bool "Verify kernel signature during kexec_file_load() syscall" 1889 depends on KEXEC_FILE 1890 ---help--- 1891 This option makes kernel signature verification mandatory for 1892 the kexec_file_load() syscall. 1893 1894 In addition to that option, you need to enable signature 1895 verification for the corresponding kernel image type being 1896 loaded in order for this to work. 1897 1898config KEXEC_BZIMAGE_VERIFY_SIG 1899 bool "Enable bzImage signature verification support" 1900 depends on KEXEC_VERIFY_SIG 1901 depends on SIGNED_PE_FILE_VERIFICATION 1902 select SYSTEM_TRUSTED_KEYRING 1903 ---help--- 1904 Enable bzImage signature verification support. 1905 1906config CRASH_DUMP 1907 bool "kernel crash dumps" 1908 depends on X86_64 || (X86_32 && HIGHMEM) 1909 ---help--- 1910 Generate crash dump after being started by kexec. 1911 This should be normally only set in special crash dump kernels 1912 which are loaded in the main kernel with kexec-tools into 1913 a specially reserved region and then later executed after 1914 a crash by kdump/kexec. The crash dump kernel must be compiled 1915 to a memory address not used by the main kernel or BIOS using 1916 PHYSICAL_START, or it must be built as a relocatable image 1917 (CONFIG_RELOCATABLE=y). 1918 For more details see Documentation/kdump/kdump.txt 1919 1920config KEXEC_JUMP 1921 bool "kexec jump" 1922 depends on KEXEC && HIBERNATION 1923 ---help--- 1924 Jump between original kernel and kexeced kernel and invoke 1925 code in physical address mode via KEXEC 1926 1927config PHYSICAL_START 1928 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1929 default "0x1000000" 1930 ---help--- 1931 This gives the physical address where the kernel is loaded. 1932 1933 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1934 bzImage will decompress itself to above physical address and 1935 run from there. Otherwise, bzImage will run from the address where 1936 it has been loaded by the boot loader and will ignore above physical 1937 address. 1938 1939 In normal kdump cases one does not have to set/change this option 1940 as now bzImage can be compiled as a completely relocatable image 1941 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1942 address. This option is mainly useful for the folks who don't want 1943 to use a bzImage for capturing the crash dump and want to use a 1944 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1945 to be specifically compiled to run from a specific memory area 1946 (normally a reserved region) and this option comes handy. 1947 1948 So if you are using bzImage for capturing the crash dump, 1949 leave the value here unchanged to 0x1000000 and set 1950 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1951 for capturing the crash dump change this value to start of 1952 the reserved region. In other words, it can be set based on 1953 the "X" value as specified in the "crashkernel=YM@XM" 1954 command line boot parameter passed to the panic-ed 1955 kernel. Please take a look at Documentation/kdump/kdump.txt 1956 for more details about crash dumps. 1957 1958 Usage of bzImage for capturing the crash dump is recommended as 1959 one does not have to build two kernels. Same kernel can be used 1960 as production kernel and capture kernel. Above option should have 1961 gone away after relocatable bzImage support is introduced. But it 1962 is present because there are users out there who continue to use 1963 vmlinux for dump capture. This option should go away down the 1964 line. 1965 1966 Don't change this unless you know what you are doing. 1967 1968config RELOCATABLE 1969 bool "Build a relocatable kernel" 1970 default y 1971 ---help--- 1972 This builds a kernel image that retains relocation information 1973 so it can be loaded someplace besides the default 1MB. 1974 The relocations tend to make the kernel binary about 10% larger, 1975 but are discarded at runtime. 1976 1977 One use is for the kexec on panic case where the recovery kernel 1978 must live at a different physical address than the primary 1979 kernel. 1980 1981 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1982 it has been loaded at and the compile time physical address 1983 (CONFIG_PHYSICAL_START) is used as the minimum location. 1984 1985config RANDOMIZE_BASE 1986 bool "Randomize the address of the kernel image (KASLR)" 1987 depends on RELOCATABLE 1988 default y 1989 ---help--- 1990 In support of Kernel Address Space Layout Randomization (KASLR), 1991 this randomizes the physical address at which the kernel image 1992 is decompressed and the virtual address where the kernel 1993 image is mapped, as a security feature that deters exploit 1994 attempts relying on knowledge of the location of kernel 1995 code internals. 1996 1997 On 64-bit, the kernel physical and virtual addresses are 1998 randomized separately. The physical address will be anywhere 1999 between 16MB and the top of physical memory (up to 64TB). The 2000 virtual address will be randomized from 16MB up to 1GB (9 bits 2001 of entropy). Note that this also reduces the memory space 2002 available to kernel modules from 1.5GB to 1GB. 2003 2004 On 32-bit, the kernel physical and virtual addresses are 2005 randomized together. They will be randomized from 16MB up to 2006 512MB (8 bits of entropy). 2007 2008 Entropy is generated using the RDRAND instruction if it is 2009 supported. If RDTSC is supported, its value is mixed into 2010 the entropy pool as well. If neither RDRAND nor RDTSC are 2011 supported, then entropy is read from the i8254 timer. The 2012 usable entropy is limited by the kernel being built using 2013 2GB addressing, and that PHYSICAL_ALIGN must be at a 2014 minimum of 2MB. As a result, only 10 bits of entropy are 2015 theoretically possible, but the implementations are further 2016 limited due to memory layouts. 2017 2018 If unsure, say Y. 2019 2020# Relocation on x86 needs some additional build support 2021config X86_NEED_RELOCS 2022 def_bool y 2023 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2024 2025config PHYSICAL_ALIGN 2026 hex "Alignment value to which kernel should be aligned" 2027 default "0x200000" 2028 range 0x2000 0x1000000 if X86_32 2029 range 0x200000 0x1000000 if X86_64 2030 ---help--- 2031 This value puts the alignment restrictions on physical address 2032 where kernel is loaded and run from. Kernel is compiled for an 2033 address which meets above alignment restriction. 2034 2035 If bootloader loads the kernel at a non-aligned address and 2036 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2037 address aligned to above value and run from there. 2038 2039 If bootloader loads the kernel at a non-aligned address and 2040 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2041 load address and decompress itself to the address it has been 2042 compiled for and run from there. The address for which kernel is 2043 compiled already meets above alignment restrictions. Hence the 2044 end result is that kernel runs from a physical address meeting 2045 above alignment restrictions. 2046 2047 On 32-bit this value must be a multiple of 0x2000. On 64-bit 2048 this value must be a multiple of 0x200000. 2049 2050 Don't change this unless you know what you are doing. 2051 2052config RANDOMIZE_MEMORY 2053 bool "Randomize the kernel memory sections" 2054 depends on X86_64 2055 depends on RANDOMIZE_BASE 2056 default RANDOMIZE_BASE 2057 ---help--- 2058 Randomizes the base virtual address of kernel memory sections 2059 (physical memory mapping, vmalloc & vmemmap). This security feature 2060 makes exploits relying on predictable memory locations less reliable. 2061 2062 The order of allocations remains unchanged. Entropy is generated in 2063 the same way as RANDOMIZE_BASE. Current implementation in the optimal 2064 configuration have in average 30,000 different possible virtual 2065 addresses for each memory section. 2066 2067 If unsure, say Y. 2068 2069config RANDOMIZE_MEMORY_PHYSICAL_PADDING 2070 hex "Physical memory mapping padding" if EXPERT 2071 depends on RANDOMIZE_MEMORY 2072 default "0xa" if MEMORY_HOTPLUG 2073 default "0x0" 2074 range 0x1 0x40 if MEMORY_HOTPLUG 2075 range 0x0 0x40 2076 ---help--- 2077 Define the padding in terabytes added to the existing physical 2078 memory size during kernel memory randomization. It is useful 2079 for memory hotplug support but reduces the entropy available for 2080 address randomization. 2081 2082 If unsure, leave at the default value. 2083 2084config HOTPLUG_CPU 2085 bool "Support for hot-pluggable CPUs" 2086 depends on SMP 2087 ---help--- 2088 Say Y here to allow turning CPUs off and on. CPUs can be 2089 controlled through /sys/devices/system/cpu. 2090 ( Note: power management support will enable this option 2091 automatically on SMP systems. ) 2092 Say N if you want to disable CPU hotplug. 2093 2094config BOOTPARAM_HOTPLUG_CPU0 2095 bool "Set default setting of cpu0_hotpluggable" 2096 default n 2097 depends on HOTPLUG_CPU 2098 ---help--- 2099 Set whether default state of cpu0_hotpluggable is on or off. 2100 2101 Say Y here to enable CPU0 hotplug by default. If this switch 2102 is turned on, there is no need to give cpu0_hotplug kernel 2103 parameter and the CPU0 hotplug feature is enabled by default. 2104 2105 Please note: there are two known CPU0 dependencies if you want 2106 to enable the CPU0 hotplug feature either by this switch or by 2107 cpu0_hotplug kernel parameter. 2108 2109 First, resume from hibernate or suspend always starts from CPU0. 2110 So hibernate and suspend are prevented if CPU0 is offline. 2111 2112 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2113 offline if any interrupt can not migrate out of CPU0. There may 2114 be other CPU0 dependencies. 2115 2116 Please make sure the dependencies are under your control before 2117 you enable this feature. 2118 2119 Say N if you don't want to enable CPU0 hotplug feature by default. 2120 You still can enable the CPU0 hotplug feature at boot by kernel 2121 parameter cpu0_hotplug. 2122 2123config DEBUG_HOTPLUG_CPU0 2124 def_bool n 2125 prompt "Debug CPU0 hotplug" 2126 depends on HOTPLUG_CPU 2127 ---help--- 2128 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2129 soon as possible and boots up userspace with CPU0 offlined. User 2130 can online CPU0 back after boot time. 2131 2132 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2133 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2134 compilation or giving cpu0_hotplug kernel parameter at boot. 2135 2136 If unsure, say N. 2137 2138config COMPAT_VDSO 2139 def_bool n 2140 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2141 depends on COMPAT_32 2142 ---help--- 2143 Certain buggy versions of glibc will crash if they are 2144 presented with a 32-bit vDSO that is not mapped at the address 2145 indicated in its segment table. 2146 2147 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2148 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2149 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2150 the only released version with the bug, but OpenSUSE 9 2151 contains a buggy "glibc 2.3.2". 2152 2153 The symptom of the bug is that everything crashes on startup, saying: 2154 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2155 2156 Saying Y here changes the default value of the vdso32 boot 2157 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2158 This works around the glibc bug but hurts performance. 2159 2160 If unsure, say N: if you are compiling your own kernel, you 2161 are unlikely to be using a buggy version of glibc. 2162 2163choice 2164 prompt "vsyscall table for legacy applications" 2165 depends on X86_64 2166 default LEGACY_VSYSCALL_EMULATE 2167 help 2168 Legacy user code that does not know how to find the vDSO expects 2169 to be able to issue three syscalls by calling fixed addresses in 2170 kernel space. Since this location is not randomized with ASLR, 2171 it can be used to assist security vulnerability exploitation. 2172 2173 This setting can be changed at boot time via the kernel command 2174 line parameter vsyscall=[native|emulate|none]. 2175 2176 On a system with recent enough glibc (2.14 or newer) and no 2177 static binaries, you can say None without a performance penalty 2178 to improve security. 2179 2180 If unsure, select "Emulate". 2181 2182 config LEGACY_VSYSCALL_NATIVE 2183 bool "Native" 2184 help 2185 Actual executable code is located in the fixed vsyscall 2186 address mapping, implementing time() efficiently. Since 2187 this makes the mapping executable, it can be used during 2188 security vulnerability exploitation (traditionally as 2189 ROP gadgets). This configuration is not recommended. 2190 2191 config LEGACY_VSYSCALL_EMULATE 2192 bool "Emulate" 2193 help 2194 The kernel traps and emulates calls into the fixed 2195 vsyscall address mapping. This makes the mapping 2196 non-executable, but it still contains known contents, 2197 which could be used in certain rare security vulnerability 2198 exploits. This configuration is recommended when userspace 2199 still uses the vsyscall area. 2200 2201 config LEGACY_VSYSCALL_NONE 2202 bool "None" 2203 help 2204 There will be no vsyscall mapping at all. This will 2205 eliminate any risk of ASLR bypass due to the vsyscall 2206 fixed address mapping. Attempts to use the vsyscalls 2207 will be reported to dmesg, so that either old or 2208 malicious userspace programs can be identified. 2209 2210endchoice 2211 2212config CMDLINE_BOOL 2213 bool "Built-in kernel command line" 2214 ---help--- 2215 Allow for specifying boot arguments to the kernel at 2216 build time. On some systems (e.g. embedded ones), it is 2217 necessary or convenient to provide some or all of the 2218 kernel boot arguments with the kernel itself (that is, 2219 to not rely on the boot loader to provide them.) 2220 2221 To compile command line arguments into the kernel, 2222 set this option to 'Y', then fill in the 2223 boot arguments in CONFIG_CMDLINE. 2224 2225 Systems with fully functional boot loaders (i.e. non-embedded) 2226 should leave this option set to 'N'. 2227 2228config CMDLINE 2229 string "Built-in kernel command string" 2230 depends on CMDLINE_BOOL 2231 default "" 2232 ---help--- 2233 Enter arguments here that should be compiled into the kernel 2234 image and used at boot time. If the boot loader provides a 2235 command line at boot time, it is appended to this string to 2236 form the full kernel command line, when the system boots. 2237 2238 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2239 change this behavior. 2240 2241 In most cases, the command line (whether built-in or provided 2242 by the boot loader) should specify the device for the root 2243 file system. 2244 2245config CMDLINE_OVERRIDE 2246 bool "Built-in command line overrides boot loader arguments" 2247 depends on CMDLINE_BOOL 2248 ---help--- 2249 Set this option to 'Y' to have the kernel ignore the boot loader 2250 command line, and use ONLY the built-in command line. 2251 2252 This is used to work around broken boot loaders. This should 2253 be set to 'N' under normal conditions. 2254 2255config MODIFY_LDT_SYSCALL 2256 bool "Enable the LDT (local descriptor table)" if EXPERT 2257 default y 2258 ---help--- 2259 Linux can allow user programs to install a per-process x86 2260 Local Descriptor Table (LDT) using the modify_ldt(2) system 2261 call. This is required to run 16-bit or segmented code such as 2262 DOSEMU or some Wine programs. It is also used by some very old 2263 threading libraries. 2264 2265 Enabling this feature adds a small amount of overhead to 2266 context switches and increases the low-level kernel attack 2267 surface. Disabling it removes the modify_ldt(2) system call. 2268 2269 Saying 'N' here may make sense for embedded or server kernels. 2270 2271source "kernel/livepatch/Kconfig" 2272 2273endmenu 2274 2275config ARCH_ENABLE_MEMORY_HOTPLUG 2276 def_bool y 2277 depends on X86_64 || (X86_32 && HIGHMEM) 2278 2279config ARCH_ENABLE_MEMORY_HOTREMOVE 2280 def_bool y 2281 depends on MEMORY_HOTPLUG 2282 2283config USE_PERCPU_NUMA_NODE_ID 2284 def_bool y 2285 depends on NUMA 2286 2287config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2288 def_bool y 2289 depends on X86_64 || X86_PAE 2290 2291config ARCH_ENABLE_HUGEPAGE_MIGRATION 2292 def_bool y 2293 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2294 2295menu "Power management and ACPI options" 2296 2297config ARCH_HIBERNATION_HEADER 2298 def_bool y 2299 depends on X86_64 && HIBERNATION 2300 2301source "kernel/power/Kconfig" 2302 2303source "drivers/acpi/Kconfig" 2304 2305source "drivers/sfi/Kconfig" 2306 2307config X86_APM_BOOT 2308 def_bool y 2309 depends on APM 2310 2311menuconfig APM 2312 tristate "APM (Advanced Power Management) BIOS support" 2313 depends on X86_32 && PM_SLEEP 2314 ---help--- 2315 APM is a BIOS specification for saving power using several different 2316 techniques. This is mostly useful for battery powered laptops with 2317 APM compliant BIOSes. If you say Y here, the system time will be 2318 reset after a RESUME operation, the /proc/apm device will provide 2319 battery status information, and user-space programs will receive 2320 notification of APM "events" (e.g. battery status change). 2321 2322 If you select "Y" here, you can disable actual use of the APM 2323 BIOS by passing the "apm=off" option to the kernel at boot time. 2324 2325 Note that the APM support is almost completely disabled for 2326 machines with more than one CPU. 2327 2328 In order to use APM, you will need supporting software. For location 2329 and more information, read <file:Documentation/power/apm-acpi.txt> 2330 and the Battery Powered Linux mini-HOWTO, available from 2331 <http://www.tldp.org/docs.html#howto>. 2332 2333 This driver does not spin down disk drives (see the hdparm(8) 2334 manpage ("man 8 hdparm") for that), and it doesn't turn off 2335 VESA-compliant "green" monitors. 2336 2337 This driver does not support the TI 4000M TravelMate and the ACER 2338 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2339 desktop machines also don't have compliant BIOSes, and this driver 2340 may cause those machines to panic during the boot phase. 2341 2342 Generally, if you don't have a battery in your machine, there isn't 2343 much point in using this driver and you should say N. If you get 2344 random kernel OOPSes or reboots that don't seem to be related to 2345 anything, try disabling/enabling this option (or disabling/enabling 2346 APM in your BIOS). 2347 2348 Some other things you should try when experiencing seemingly random, 2349 "weird" problems: 2350 2351 1) make sure that you have enough swap space and that it is 2352 enabled. 2353 2) pass the "no-hlt" option to the kernel 2354 3) switch on floating point emulation in the kernel and pass 2355 the "no387" option to the kernel 2356 4) pass the "floppy=nodma" option to the kernel 2357 5) pass the "mem=4M" option to the kernel (thereby disabling 2358 all but the first 4 MB of RAM) 2359 6) make sure that the CPU is not over clocked. 2360 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2361 8) disable the cache from your BIOS settings 2362 9) install a fan for the video card or exchange video RAM 2363 10) install a better fan for the CPU 2364 11) exchange RAM chips 2365 12) exchange the motherboard. 2366 2367 To compile this driver as a module, choose M here: the 2368 module will be called apm. 2369 2370if APM 2371 2372config APM_IGNORE_USER_SUSPEND 2373 bool "Ignore USER SUSPEND" 2374 ---help--- 2375 This option will ignore USER SUSPEND requests. On machines with a 2376 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2377 series notebooks, it is necessary to say Y because of a BIOS bug. 2378 2379config APM_DO_ENABLE 2380 bool "Enable PM at boot time" 2381 ---help--- 2382 Enable APM features at boot time. From page 36 of the APM BIOS 2383 specification: "When disabled, the APM BIOS does not automatically 2384 power manage devices, enter the Standby State, enter the Suspend 2385 State, or take power saving steps in response to CPU Idle calls." 2386 This driver will make CPU Idle calls when Linux is idle (unless this 2387 feature is turned off -- see "Do CPU IDLE calls", below). This 2388 should always save battery power, but more complicated APM features 2389 will be dependent on your BIOS implementation. You may need to turn 2390 this option off if your computer hangs at boot time when using APM 2391 support, or if it beeps continuously instead of suspending. Turn 2392 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2393 T400CDT. This is off by default since most machines do fine without 2394 this feature. 2395 2396config APM_CPU_IDLE 2397 depends on CPU_IDLE 2398 bool "Make CPU Idle calls when idle" 2399 ---help--- 2400 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2401 On some machines, this can activate improved power savings, such as 2402 a slowed CPU clock rate, when the machine is idle. These idle calls 2403 are made after the idle loop has run for some length of time (e.g., 2404 333 mS). On some machines, this will cause a hang at boot time or 2405 whenever the CPU becomes idle. (On machines with more than one CPU, 2406 this option does nothing.) 2407 2408config APM_DISPLAY_BLANK 2409 bool "Enable console blanking using APM" 2410 ---help--- 2411 Enable console blanking using the APM. Some laptops can use this to 2412 turn off the LCD backlight when the screen blanker of the Linux 2413 virtual console blanks the screen. Note that this is only used by 2414 the virtual console screen blanker, and won't turn off the backlight 2415 when using the X Window system. This also doesn't have anything to 2416 do with your VESA-compliant power-saving monitor. Further, this 2417 option doesn't work for all laptops -- it might not turn off your 2418 backlight at all, or it might print a lot of errors to the console, 2419 especially if you are using gpm. 2420 2421config APM_ALLOW_INTS 2422 bool "Allow interrupts during APM BIOS calls" 2423 ---help--- 2424 Normally we disable external interrupts while we are making calls to 2425 the APM BIOS as a measure to lessen the effects of a badly behaving 2426 BIOS implementation. The BIOS should reenable interrupts if it 2427 needs to. Unfortunately, some BIOSes do not -- especially those in 2428 many of the newer IBM Thinkpads. If you experience hangs when you 2429 suspend, try setting this to Y. Otherwise, say N. 2430 2431endif # APM 2432 2433source "drivers/cpufreq/Kconfig" 2434 2435source "drivers/cpuidle/Kconfig" 2436 2437source "drivers/idle/Kconfig" 2438 2439endmenu 2440 2441 2442menu "Bus options (PCI etc.)" 2443 2444config PCI 2445 bool "PCI support" 2446 default y 2447 ---help--- 2448 Find out whether you have a PCI motherboard. PCI is the name of a 2449 bus system, i.e. the way the CPU talks to the other stuff inside 2450 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2451 VESA. If you have PCI, say Y, otherwise N. 2452 2453choice 2454 prompt "PCI access mode" 2455 depends on X86_32 && PCI 2456 default PCI_GOANY 2457 ---help--- 2458 On PCI systems, the BIOS can be used to detect the PCI devices and 2459 determine their configuration. However, some old PCI motherboards 2460 have BIOS bugs and may crash if this is done. Also, some embedded 2461 PCI-based systems don't have any BIOS at all. Linux can also try to 2462 detect the PCI hardware directly without using the BIOS. 2463 2464 With this option, you can specify how Linux should detect the 2465 PCI devices. If you choose "BIOS", the BIOS will be used, 2466 if you choose "Direct", the BIOS won't be used, and if you 2467 choose "MMConfig", then PCI Express MMCONFIG will be used. 2468 If you choose "Any", the kernel will try MMCONFIG, then the 2469 direct access method and falls back to the BIOS if that doesn't 2470 work. If unsure, go with the default, which is "Any". 2471 2472config PCI_GOBIOS 2473 bool "BIOS" 2474 2475config PCI_GOMMCONFIG 2476 bool "MMConfig" 2477 2478config PCI_GODIRECT 2479 bool "Direct" 2480 2481config PCI_GOOLPC 2482 bool "OLPC XO-1" 2483 depends on OLPC 2484 2485config PCI_GOANY 2486 bool "Any" 2487 2488endchoice 2489 2490config PCI_BIOS 2491 def_bool y 2492 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2493 2494# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2495config PCI_DIRECT 2496 def_bool y 2497 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2498 2499config PCI_MMCONFIG 2500 def_bool y 2501 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2502 2503config PCI_OLPC 2504 def_bool y 2505 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2506 2507config PCI_XEN 2508 def_bool y 2509 depends on PCI && XEN 2510 select SWIOTLB_XEN 2511 2512config PCI_DOMAINS 2513 def_bool y 2514 depends on PCI 2515 2516config PCI_MMCONFIG 2517 bool "Support mmconfig PCI config space access" 2518 depends on X86_64 && PCI && ACPI 2519 2520config PCI_CNB20LE_QUIRK 2521 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2522 depends on PCI 2523 help 2524 Read the PCI windows out of the CNB20LE host bridge. This allows 2525 PCI hotplug to work on systems with the CNB20LE chipset which do 2526 not have ACPI. 2527 2528 There's no public spec for this chipset, and this functionality 2529 is known to be incomplete. 2530 2531 You should say N unless you know you need this. 2532 2533source "drivers/pci/Kconfig" 2534 2535config ISA_BUS 2536 bool "ISA-style bus support on modern systems" if EXPERT 2537 select ISA_BUS_API 2538 help 2539 Enables ISA-style drivers on modern systems. This is necessary to 2540 support PC/104 devices on X86_64 platforms. 2541 2542 If unsure, say N. 2543 2544# x86_64 have no ISA slots, but can have ISA-style DMA. 2545config ISA_DMA_API 2546 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2547 default y 2548 help 2549 Enables ISA-style DMA support for devices requiring such controllers. 2550 If unsure, say Y. 2551 2552if X86_32 2553 2554config ISA 2555 bool "ISA support" 2556 ---help--- 2557 Find out whether you have ISA slots on your motherboard. ISA is the 2558 name of a bus system, i.e. the way the CPU talks to the other stuff 2559 inside your box. Other bus systems are PCI, EISA, MicroChannel 2560 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2561 newer boards don't support it. If you have ISA, say Y, otherwise N. 2562 2563config EISA 2564 bool "EISA support" 2565 depends on ISA 2566 ---help--- 2567 The Extended Industry Standard Architecture (EISA) bus was 2568 developed as an open alternative to the IBM MicroChannel bus. 2569 2570 The EISA bus provided some of the features of the IBM MicroChannel 2571 bus while maintaining backward compatibility with cards made for 2572 the older ISA bus. The EISA bus saw limited use between 1988 and 2573 1995 when it was made obsolete by the PCI bus. 2574 2575 Say Y here if you are building a kernel for an EISA-based machine. 2576 2577 Otherwise, say N. 2578 2579source "drivers/eisa/Kconfig" 2580 2581config SCx200 2582 tristate "NatSemi SCx200 support" 2583 ---help--- 2584 This provides basic support for National Semiconductor's 2585 (now AMD's) Geode processors. The driver probes for the 2586 PCI-IDs of several on-chip devices, so its a good dependency 2587 for other scx200_* drivers. 2588 2589 If compiled as a module, the driver is named scx200. 2590 2591config SCx200HR_TIMER 2592 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2593 depends on SCx200 2594 default y 2595 ---help--- 2596 This driver provides a clocksource built upon the on-chip 2597 27MHz high-resolution timer. Its also a workaround for 2598 NSC Geode SC-1100's buggy TSC, which loses time when the 2599 processor goes idle (as is done by the scheduler). The 2600 other workaround is idle=poll boot option. 2601 2602config OLPC 2603 bool "One Laptop Per Child support" 2604 depends on !X86_PAE 2605 select GPIOLIB 2606 select OF 2607 select OF_PROMTREE 2608 select IRQ_DOMAIN 2609 ---help--- 2610 Add support for detecting the unique features of the OLPC 2611 XO hardware. 2612 2613config OLPC_XO1_PM 2614 bool "OLPC XO-1 Power Management" 2615 depends on OLPC && MFD_CS5535 && PM_SLEEP 2616 select MFD_CORE 2617 ---help--- 2618 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2619 2620config OLPC_XO1_RTC 2621 bool "OLPC XO-1 Real Time Clock" 2622 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2623 ---help--- 2624 Add support for the XO-1 real time clock, which can be used as a 2625 programmable wakeup source. 2626 2627config OLPC_XO1_SCI 2628 bool "OLPC XO-1 SCI extras" 2629 depends on OLPC && OLPC_XO1_PM 2630 depends on INPUT=y 2631 select POWER_SUPPLY 2632 select GPIO_CS5535 2633 select MFD_CORE 2634 ---help--- 2635 Add support for SCI-based features of the OLPC XO-1 laptop: 2636 - EC-driven system wakeups 2637 - Power button 2638 - Ebook switch 2639 - Lid switch 2640 - AC adapter status updates 2641 - Battery status updates 2642 2643config OLPC_XO15_SCI 2644 bool "OLPC XO-1.5 SCI extras" 2645 depends on OLPC && ACPI 2646 select POWER_SUPPLY 2647 ---help--- 2648 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2649 - EC-driven system wakeups 2650 - AC adapter status updates 2651 - Battery status updates 2652 2653config ALIX 2654 bool "PCEngines ALIX System Support (LED setup)" 2655 select GPIOLIB 2656 ---help--- 2657 This option enables system support for the PCEngines ALIX. 2658 At present this just sets up LEDs for GPIO control on 2659 ALIX2/3/6 boards. However, other system specific setup should 2660 get added here. 2661 2662 Note: You must still enable the drivers for GPIO and LED support 2663 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2664 2665 Note: You have to set alix.force=1 for boards with Award BIOS. 2666 2667config NET5501 2668 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2669 select GPIOLIB 2670 ---help--- 2671 This option enables system support for the Soekris Engineering net5501. 2672 2673config GEOS 2674 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2675 select GPIOLIB 2676 depends on DMI 2677 ---help--- 2678 This option enables system support for the Traverse Technologies GEOS. 2679 2680config TS5500 2681 bool "Technologic Systems TS-5500 platform support" 2682 depends on MELAN 2683 select CHECK_SIGNATURE 2684 select NEW_LEDS 2685 select LEDS_CLASS 2686 ---help--- 2687 This option enables system support for the Technologic Systems TS-5500. 2688 2689endif # X86_32 2690 2691config AMD_NB 2692 def_bool y 2693 depends on CPU_SUP_AMD && PCI 2694 2695source "drivers/pcmcia/Kconfig" 2696 2697config RAPIDIO 2698 tristate "RapidIO support" 2699 depends on PCI 2700 default n 2701 help 2702 If enabled this option will include drivers and the core 2703 infrastructure code to support RapidIO interconnect devices. 2704 2705source "drivers/rapidio/Kconfig" 2706 2707config X86_SYSFB 2708 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2709 help 2710 Firmwares often provide initial graphics framebuffers so the BIOS, 2711 bootloader or kernel can show basic video-output during boot for 2712 user-guidance and debugging. Historically, x86 used the VESA BIOS 2713 Extensions and EFI-framebuffers for this, which are mostly limited 2714 to x86. 2715 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2716 framebuffers so the new generic system-framebuffer drivers can be 2717 used on x86. If the framebuffer is not compatible with the generic 2718 modes, it is adverticed as fallback platform framebuffer so legacy 2719 drivers like efifb, vesafb and uvesafb can pick it up. 2720 If this option is not selected, all system framebuffers are always 2721 marked as fallback platform framebuffers as usual. 2722 2723 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2724 not be able to pick up generic system framebuffers if this option 2725 is selected. You are highly encouraged to enable simplefb as 2726 replacement if you select this option. simplefb can correctly deal 2727 with generic system framebuffers. But you should still keep vesafb 2728 and others enabled as fallback if a system framebuffer is 2729 incompatible with simplefb. 2730 2731 If unsure, say Y. 2732 2733endmenu 2734 2735 2736menu "Executable file formats / Emulations" 2737 2738source "fs/Kconfig.binfmt" 2739 2740config IA32_EMULATION 2741 bool "IA32 Emulation" 2742 depends on X86_64 2743 select ARCH_WANT_OLD_COMPAT_IPC 2744 select BINFMT_ELF 2745 select COMPAT_BINFMT_ELF 2746 select COMPAT_OLD_SIGACTION 2747 ---help--- 2748 Include code to run legacy 32-bit programs under a 2749 64-bit kernel. You should likely turn this on, unless you're 2750 100% sure that you don't have any 32-bit programs left. 2751 2752config IA32_AOUT 2753 tristate "IA32 a.out support" 2754 depends on IA32_EMULATION 2755 ---help--- 2756 Support old a.out binaries in the 32bit emulation. 2757 2758config X86_X32 2759 bool "x32 ABI for 64-bit mode" 2760 depends on X86_64 2761 ---help--- 2762 Include code to run binaries for the x32 native 32-bit ABI 2763 for 64-bit processors. An x32 process gets access to the 2764 full 64-bit register file and wide data path while leaving 2765 pointers at 32 bits for smaller memory footprint. 2766 2767 You will need a recent binutils (2.22 or later) with 2768 elf32_x86_64 support enabled to compile a kernel with this 2769 option set. 2770 2771config COMPAT_32 2772 def_bool y 2773 depends on IA32_EMULATION || X86_32 2774 select HAVE_UID16 2775 select OLD_SIGSUSPEND3 2776 2777config COMPAT 2778 def_bool y 2779 depends on IA32_EMULATION || X86_X32 2780 2781if COMPAT 2782config COMPAT_FOR_U64_ALIGNMENT 2783 def_bool y 2784 2785config SYSVIPC_COMPAT 2786 def_bool y 2787 depends on SYSVIPC 2788endif 2789 2790endmenu 2791 2792 2793config HAVE_ATOMIC_IOMAP 2794 def_bool y 2795 depends on X86_32 2796 2797config X86_DEV_DMA_OPS 2798 bool 2799 depends on X86_64 || STA2X11 2800 2801config X86_DMA_REMAP 2802 bool 2803 depends on STA2X11 2804 2805config HAVE_GENERIC_GUP 2806 def_bool y 2807 2808source "net/Kconfig" 2809 2810source "drivers/Kconfig" 2811 2812source "drivers/firmware/Kconfig" 2813 2814source "fs/Kconfig" 2815 2816source "arch/x86/Kconfig.debug" 2817 2818source "security/Kconfig" 2819 2820source "crypto/Kconfig" 2821 2822source "arch/x86/kvm/Kconfig" 2823 2824source "lib/Kconfig" 2825