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