1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH != "i386" 5 ---help--- 6 Say yes to build a 64-bit kernel - formerly known as x86_64 7 Say no to build a 32-bit kernel - formerly known as i386 8 9config X86_32 10 def_bool y 11 depends on !64BIT 12 # Options that are inherently 32-bit kernel only: 13 select ARCH_WANT_IPC_PARSE_VERSION 14 select CLKSRC_I8253 15 select CLONE_BACKWARDS 16 select HAVE_AOUT 17 select HAVE_GENERIC_DMA_COHERENT 18 select MODULES_USE_ELF_REL 19 select OLD_SIGACTION 20 21config X86_64 22 def_bool y 23 depends on 64BIT 24 # Options that are inherently 64-bit kernel only: 25 select ARCH_HAS_GIGANTIC_PAGE 26 select ARCH_SUPPORTS_INT128 27 select ARCH_USE_CMPXCHG_LOCKREF 28 select HAVE_ARCH_SOFT_DIRTY 29 select MODULES_USE_ELF_RELA 30 select X86_DEV_DMA_OPS 31 32# 33# Arch settings 34# 35# ( Note that options that are marked 'if X86_64' could in principle be 36# ported to 32-bit as well. ) 37# 38config X86 39 def_bool y 40 # 41 # Note: keep this list sorted alphabetically 42 # 43 select ACPI_LEGACY_TABLES_LOOKUP if ACPI 44 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 45 select ANON_INODES 46 select ARCH_CLOCKSOURCE_DATA 47 select ARCH_DISCARD_MEMBLOCK 48 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 49 select ARCH_HAS_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_GCOV_PROFILE_ALL 54 select ARCH_HAS_KCOV if X86_64 55 select ARCH_HAS_MMIO_FLUSH 56 select ARCH_HAS_PMEM_API if X86_64 57 select ARCH_HAS_SET_MEMORY 58 select ARCH_HAS_SG_CHAIN 59 select ARCH_HAS_STRICT_KERNEL_RWX 60 select ARCH_HAS_STRICT_MODULE_RWX 61 select ARCH_HAS_UBSAN_SANITIZE_ALL 62 select ARCH_HAVE_NMI_SAFE_CMPXCHG 63 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 64 select ARCH_MIGHT_HAVE_PC_PARPORT 65 select ARCH_MIGHT_HAVE_PC_SERIO 66 select ARCH_SUPPORTS_ATOMIC_RMW 67 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 68 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 69 select ARCH_USE_BUILTIN_BSWAP 70 select ARCH_USE_QUEUED_RWLOCKS 71 select ARCH_USE_QUEUED_SPINLOCKS 72 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 73 select ARCH_WANT_FRAME_POINTERS 74 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 75 select BUILDTIME_EXTABLE_SORT 76 select CLKEVT_I8253 77 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 78 select CLOCKSOURCE_WATCHDOG 79 select DCACHE_WORD_ACCESS 80 select EDAC_ATOMIC_SCRUB 81 select EDAC_SUPPORT 82 select GENERIC_CLOCKEVENTS 83 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 84 select GENERIC_CLOCKEVENTS_MIN_ADJUST 85 select GENERIC_CMOS_UPDATE 86 select GENERIC_CPU_AUTOPROBE 87 select GENERIC_EARLY_IOREMAP 88 select GENERIC_FIND_FIRST_BIT 89 select GENERIC_IOMAP 90 select GENERIC_IRQ_PROBE 91 select GENERIC_IRQ_SHOW 92 select GENERIC_PENDING_IRQ if SMP 93 select GENERIC_SMP_IDLE_THREAD 94 select GENERIC_STRNCPY_FROM_USER 95 select GENERIC_STRNLEN_USER 96 select GENERIC_TIME_VSYSCALL 97 select HAVE_ACPI_APEI if ACPI 98 select HAVE_ACPI_APEI_NMI if ACPI 99 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 100 select HAVE_ARCH_AUDITSYSCALL 101 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 102 select HAVE_ARCH_JUMP_LABEL 103 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 104 select HAVE_ARCH_KGDB 105 select HAVE_ARCH_KMEMCHECK 106 select HAVE_ARCH_MMAP_RND_BITS if MMU 107 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 108 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 109 select HAVE_ARCH_SECCOMP_FILTER 110 select HAVE_ARCH_TRACEHOOK 111 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 112 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 113 select HAVE_ARCH_VMAP_STACK if X86_64 114 select HAVE_ARCH_WITHIN_STACK_FRAMES 115 select HAVE_CC_STACKPROTECTOR 116 select HAVE_CMPXCHG_DOUBLE 117 select HAVE_CMPXCHG_LOCAL 118 select HAVE_CONTEXT_TRACKING if X86_64 119 select HAVE_COPY_THREAD_TLS 120 select HAVE_C_RECORDMCOUNT 121 select HAVE_DEBUG_KMEMLEAK 122 select HAVE_DEBUG_STACKOVERFLOW 123 select HAVE_DMA_API_DEBUG 124 select HAVE_DMA_CONTIGUOUS 125 select HAVE_DYNAMIC_FTRACE 126 select HAVE_DYNAMIC_FTRACE_WITH_REGS 127 select HAVE_EBPF_JIT if X86_64 128 select HAVE_EFFICIENT_UNALIGNED_ACCESS 129 select HAVE_EXIT_THREAD 130 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 131 select HAVE_FTRACE_MCOUNT_RECORD 132 select HAVE_FUNCTION_GRAPH_TRACER 133 select HAVE_FUNCTION_TRACER 134 select HAVE_GCC_PLUGINS 135 select HAVE_HW_BREAKPOINT 136 select HAVE_IDE 137 select HAVE_IOREMAP_PROT 138 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 139 select HAVE_IRQ_TIME_ACCOUNTING 140 select HAVE_KERNEL_BZIP2 141 select HAVE_KERNEL_GZIP 142 select HAVE_KERNEL_LZ4 143 select HAVE_KERNEL_LZMA 144 select HAVE_KERNEL_LZO 145 select HAVE_KERNEL_XZ 146 select HAVE_KPROBES 147 select HAVE_KPROBES_ON_FTRACE 148 select HAVE_KRETPROBES 149 select HAVE_KVM 150 select HAVE_LIVEPATCH if X86_64 151 select HAVE_MEMBLOCK 152 select HAVE_MEMBLOCK_NODE_MAP 153 select HAVE_MIXED_BREAKPOINTS_REGS 154 select HAVE_NMI 155 select HAVE_OPROFILE 156 select HAVE_OPTPROBES 157 select HAVE_PCSPKR_PLATFORM 158 select HAVE_PERF_EVENTS 159 select HAVE_PERF_EVENTS_NMI 160 select HAVE_PERF_REGS 161 select HAVE_PERF_USER_STACK_DUMP 162 select HAVE_REGS_AND_STACK_ACCESS_API 163 select HAVE_RELIABLE_STACKTRACE if X86_64 && FRAME_POINTER && STACK_VALIDATION 164 select HAVE_STACK_VALIDATION if X86_64 165 select HAVE_SYSCALL_TRACEPOINTS 166 select HAVE_UNSTABLE_SCHED_CLOCK 167 select HAVE_USER_RETURN_NOTIFIER 168 select IRQ_FORCED_THREADING 169 select PERF_EVENTS 170 select RTC_LIB 171 select RTC_MC146818_LIB 172 select SPARSE_IRQ 173 select SRCU 174 select SYSCTL_EXCEPTION_TRACE 175 select THREAD_INFO_IN_TASK 176 select USER_STACKTRACE_SUPPORT 177 select VIRT_TO_BUS 178 select X86_FEATURE_NAMES if PROC_FS 179 180config INSTRUCTION_DECODER 181 def_bool y 182 depends on KPROBES || PERF_EVENTS || UPROBES 183 184config OUTPUT_FORMAT 185 string 186 default "elf32-i386" if X86_32 187 default "elf64-x86-64" if X86_64 188 189config ARCH_DEFCONFIG 190 string 191 default "arch/x86/configs/i386_defconfig" if X86_32 192 default "arch/x86/configs/x86_64_defconfig" if X86_64 193 194config LOCKDEP_SUPPORT 195 def_bool y 196 197config STACKTRACE_SUPPORT 198 def_bool y 199 200config MMU 201 def_bool y 202 203config ARCH_MMAP_RND_BITS_MIN 204 default 28 if 64BIT 205 default 8 206 207config ARCH_MMAP_RND_BITS_MAX 208 default 32 if 64BIT 209 default 16 210 211config ARCH_MMAP_RND_COMPAT_BITS_MIN 212 default 8 213 214config ARCH_MMAP_RND_COMPAT_BITS_MAX 215 default 16 216 217config SBUS 218 bool 219 220config NEED_DMA_MAP_STATE 221 def_bool y 222 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 223 224config NEED_SG_DMA_LENGTH 225 def_bool y 226 227config GENERIC_ISA_DMA 228 def_bool y 229 depends on ISA_DMA_API 230 231config GENERIC_BUG 232 def_bool y 233 depends on BUG 234 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 235 236config GENERIC_BUG_RELATIVE_POINTERS 237 bool 238 239config GENERIC_HWEIGHT 240 def_bool y 241 242config ARCH_MAY_HAVE_PC_FDC 243 def_bool y 244 depends on ISA_DMA_API 245 246config RWSEM_XCHGADD_ALGORITHM 247 def_bool y 248 249config GENERIC_CALIBRATE_DELAY 250 def_bool y 251 252config ARCH_HAS_CPU_RELAX 253 def_bool y 254 255config ARCH_HAS_CACHE_LINE_SIZE 256 def_bool y 257 258config HAVE_SETUP_PER_CPU_AREA 259 def_bool y 260 261config NEED_PER_CPU_EMBED_FIRST_CHUNK 262 def_bool y 263 264config NEED_PER_CPU_PAGE_FIRST_CHUNK 265 def_bool y 266 267config ARCH_HIBERNATION_POSSIBLE 268 def_bool y 269 270config ARCH_SUSPEND_POSSIBLE 271 def_bool y 272 273config ARCH_WANT_HUGE_PMD_SHARE 274 def_bool y 275 276config ARCH_WANT_GENERAL_HUGETLB 277 def_bool y 278 279config ZONE_DMA32 280 def_bool y if X86_64 281 282config AUDIT_ARCH 283 def_bool y if X86_64 284 285config ARCH_SUPPORTS_OPTIMIZED_INLINING 286 def_bool y 287 288config ARCH_SUPPORTS_DEBUG_PAGEALLOC 289 def_bool y 290 291config KASAN_SHADOW_OFFSET 292 hex 293 depends on KASAN 294 default 0xdff8000000000000 if X86_5LEVEL 295 default 0xdffffc0000000000 296 297config HAVE_INTEL_TXT 298 def_bool y 299 depends on INTEL_IOMMU && ACPI 300 301config X86_32_SMP 302 def_bool y 303 depends on X86_32 && SMP 304 305config X86_64_SMP 306 def_bool y 307 depends on X86_64 && SMP 308 309config X86_32_LAZY_GS 310 def_bool y 311 depends on X86_32 && !CC_STACKPROTECTOR 312 313config ARCH_SUPPORTS_UPROBES 314 def_bool y 315 316config FIX_EARLYCON_MEM 317 def_bool y 318 319config PGTABLE_LEVELS 320 int 321 default 4 if X86_64 322 default 3 if X86_PAE 323 default 2 324 325source "init/Kconfig" 326source "kernel/Kconfig.freezer" 327 328menu "Processor type and features" 329 330config ZONE_DMA 331 bool "DMA memory allocation support" if EXPERT 332 default y 333 help 334 DMA memory allocation support allows devices with less than 32-bit 335 addressing to allocate within the first 16MB of address space. 336 Disable if no such devices will be used. 337 338 If unsure, say Y. 339 340config SMP 341 bool "Symmetric multi-processing support" 342 ---help--- 343 This enables support for systems with more than one CPU. If you have 344 a system with only one CPU, say N. If you have a system with more 345 than one CPU, say Y. 346 347 If you say N here, the kernel will run on uni- and multiprocessor 348 machines, but will use only one CPU of a multiprocessor machine. If 349 you say Y here, the kernel will run on many, but not all, 350 uniprocessor machines. On a uniprocessor machine, the kernel 351 will run faster if you say N here. 352 353 Note that if you say Y here and choose architecture "586" or 354 "Pentium" under "Processor family", the kernel will not work on 486 355 architectures. Similarly, multiprocessor kernels for the "PPro" 356 architecture may not work on all Pentium based boards. 357 358 People using multiprocessor machines who say Y here should also say 359 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 360 Management" code will be disabled if you say Y here. 361 362 See also <file:Documentation/x86/i386/IO-APIC.txt>, 363 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 364 <http://www.tldp.org/docs.html#howto>. 365 366 If you don't know what to do here, say N. 367 368config X86_FEATURE_NAMES 369 bool "Processor feature human-readable names" if EMBEDDED 370 default y 371 ---help--- 372 This option compiles in a table of x86 feature bits and corresponding 373 names. This is required to support /proc/cpuinfo and a few kernel 374 messages. You can disable this to save space, at the expense of 375 making those few kernel messages show numeric feature bits instead. 376 377 If in doubt, say Y. 378 379config X86_FAST_FEATURE_TESTS 380 bool "Fast CPU feature tests" if EMBEDDED 381 default y 382 ---help--- 383 Some fast-paths in the kernel depend on the capabilities of the CPU. 384 Say Y here for the kernel to patch in the appropriate code at runtime 385 based on the capabilities of the CPU. The infrastructure for patching 386 code at runtime takes up some additional space; space-constrained 387 embedded systems may wish to say N here to produce smaller, slightly 388 slower code. 389 390config X86_X2APIC 391 bool "Support x2apic" 392 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 393 ---help--- 394 This enables x2apic support on CPUs that have this feature. 395 396 This allows 32-bit apic IDs (so it can support very large systems), 397 and accesses the local apic via MSRs not via mmio. 398 399 If you don't know what to do here, say N. 400 401config X86_MPPARSE 402 bool "Enable MPS table" if ACPI || SFI 403 default y 404 depends on X86_LOCAL_APIC 405 ---help--- 406 For old smp systems that do not have proper acpi support. Newer systems 407 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 408 409config X86_BIGSMP 410 bool "Support for big SMP systems with more than 8 CPUs" 411 depends on X86_32 && SMP 412 ---help--- 413 This option is needed for the systems that have more than 8 CPUs 414 415config GOLDFISH 416 def_bool y 417 depends on X86_GOLDFISH 418 419config INTEL_RDT_A 420 bool "Intel Resource Director Technology Allocation support" 421 default n 422 depends on X86 && CPU_SUP_INTEL 423 select KERNFS 424 help 425 Select to enable resource allocation which is a sub-feature of 426 Intel Resource Director Technology(RDT). More information about 427 RDT can be found in the Intel x86 Architecture Software 428 Developer Manual. 429 430 Say N if unsure. 431 432if X86_32 433config X86_EXTENDED_PLATFORM 434 bool "Support for extended (non-PC) x86 platforms" 435 default y 436 ---help--- 437 If you disable this option then the kernel will only support 438 standard PC platforms. (which covers the vast majority of 439 systems out there.) 440 441 If you enable this option then you'll be able to select support 442 for the following (non-PC) 32 bit x86 platforms: 443 Goldfish (Android emulator) 444 AMD Elan 445 RDC R-321x SoC 446 SGI 320/540 (Visual Workstation) 447 STA2X11-based (e.g. Northville) 448 Moorestown MID devices 449 450 If you have one of these systems, or if you want to build a 451 generic distribution kernel, say Y here - otherwise say N. 452endif 453 454if X86_64 455config X86_EXTENDED_PLATFORM 456 bool "Support for extended (non-PC) x86 platforms" 457 default y 458 ---help--- 459 If you disable this option then the kernel will only support 460 standard PC platforms. (which covers the vast majority of 461 systems out there.) 462 463 If you enable this option then you'll be able to select support 464 for the following (non-PC) 64 bit x86 platforms: 465 Numascale NumaChip 466 ScaleMP vSMP 467 SGI Ultraviolet 468 469 If you have one of these systems, or if you want to build a 470 generic distribution kernel, say Y here - otherwise say N. 471endif 472# This is an alphabetically sorted list of 64 bit extended platforms 473# Please maintain the alphabetic order if and when there are additions 474config X86_NUMACHIP 475 bool "Numascale NumaChip" 476 depends on X86_64 477 depends on X86_EXTENDED_PLATFORM 478 depends on NUMA 479 depends on SMP 480 depends on X86_X2APIC 481 depends on PCI_MMCONFIG 482 ---help--- 483 Adds support for Numascale NumaChip large-SMP systems. Needed to 484 enable more than ~168 cores. 485 If you don't have one of these, you should say N here. 486 487config X86_VSMP 488 bool "ScaleMP vSMP" 489 select HYPERVISOR_GUEST 490 select PARAVIRT 491 depends on X86_64 && PCI 492 depends on X86_EXTENDED_PLATFORM 493 depends on SMP 494 ---help--- 495 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 496 supposed to run on these EM64T-based machines. Only choose this option 497 if you have one of these machines. 498 499config X86_UV 500 bool "SGI Ultraviolet" 501 depends on X86_64 502 depends on X86_EXTENDED_PLATFORM 503 depends on NUMA 504 depends on EFI 505 depends on X86_X2APIC 506 depends on PCI 507 ---help--- 508 This option is needed in order to support SGI Ultraviolet systems. 509 If you don't have one of these, you should say N here. 510 511# Following is an alphabetically sorted list of 32 bit extended platforms 512# Please maintain the alphabetic order if and when there are additions 513 514config X86_GOLDFISH 515 bool "Goldfish (Virtual Platform)" 516 depends on X86_EXTENDED_PLATFORM 517 ---help--- 518 Enable support for the Goldfish virtual platform used primarily 519 for Android development. Unless you are building for the Android 520 Goldfish emulator say N here. 521 522config X86_INTEL_CE 523 bool "CE4100 TV platform" 524 depends on PCI 525 depends on PCI_GODIRECT 526 depends on X86_IO_APIC 527 depends on X86_32 528 depends on X86_EXTENDED_PLATFORM 529 select X86_REBOOTFIXUPS 530 select OF 531 select OF_EARLY_FLATTREE 532 ---help--- 533 Select for the Intel CE media processor (CE4100) SOC. 534 This option compiles in support for the CE4100 SOC for settop 535 boxes and media devices. 536 537config X86_INTEL_MID 538 bool "Intel MID platform support" 539 depends on X86_EXTENDED_PLATFORM 540 depends on X86_PLATFORM_DEVICES 541 depends on PCI 542 depends on X86_64 || (PCI_GOANY && X86_32) 543 depends on X86_IO_APIC 544 select SFI 545 select I2C 546 select DW_APB_TIMER 547 select APB_TIMER 548 select INTEL_SCU_IPC 549 select MFD_INTEL_MSIC 550 ---help--- 551 Select to build a kernel capable of supporting Intel MID (Mobile 552 Internet Device) platform systems which do not have the PCI legacy 553 interfaces. If you are building for a PC class system say N here. 554 555 Intel MID platforms are based on an Intel processor and chipset which 556 consume less power than most of the x86 derivatives. 557 558config X86_INTEL_QUARK 559 bool "Intel Quark platform support" 560 depends on X86_32 561 depends on X86_EXTENDED_PLATFORM 562 depends on X86_PLATFORM_DEVICES 563 depends on X86_TSC 564 depends on PCI 565 depends on PCI_GOANY 566 depends on X86_IO_APIC 567 select IOSF_MBI 568 select INTEL_IMR 569 select COMMON_CLK 570 ---help--- 571 Select to include support for Quark X1000 SoC. 572 Say Y here if you have a Quark based system such as the Arduino 573 compatible Intel Galileo. 574 575config X86_INTEL_LPSS 576 bool "Intel Low Power Subsystem Support" 577 depends on X86 && ACPI 578 select COMMON_CLK 579 select PINCTRL 580 select IOSF_MBI 581 ---help--- 582 Select to build support for Intel Low Power Subsystem such as 583 found on Intel Lynxpoint PCH. Selecting this option enables 584 things like clock tree (common clock framework) and pincontrol 585 which are needed by the LPSS peripheral drivers. 586 587config X86_AMD_PLATFORM_DEVICE 588 bool "AMD ACPI2Platform devices support" 589 depends on ACPI 590 select COMMON_CLK 591 select PINCTRL 592 ---help--- 593 Select to interpret AMD specific ACPI device to platform device 594 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 595 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 596 implemented under PINCTRL subsystem. 597 598config IOSF_MBI 599 tristate "Intel SoC IOSF Sideband support for SoC platforms" 600 depends on PCI 601 ---help--- 602 This option enables sideband register access support for Intel SoC 603 platforms. On these platforms the IOSF sideband is used in lieu of 604 MSR's for some register accesses, mostly but not limited to thermal 605 and power. Drivers may query the availability of this device to 606 determine if they need the sideband in order to work on these 607 platforms. The sideband is available on the following SoC products. 608 This list is not meant to be exclusive. 609 - BayTrail 610 - Braswell 611 - Quark 612 613 You should say Y if you are running a kernel on one of these SoC's. 614 615config IOSF_MBI_DEBUG 616 bool "Enable IOSF sideband access through debugfs" 617 depends on IOSF_MBI && DEBUG_FS 618 ---help--- 619 Select this option to expose the IOSF sideband access registers (MCR, 620 MDR, MCRX) through debugfs to write and read register information from 621 different units on the SoC. This is most useful for obtaining device 622 state information for debug and analysis. As this is a general access 623 mechanism, users of this option would have specific knowledge of the 624 device they want to access. 625 626 If you don't require the option or are in doubt, say N. 627 628config X86_RDC321X 629 bool "RDC R-321x SoC" 630 depends on X86_32 631 depends on X86_EXTENDED_PLATFORM 632 select M486 633 select X86_REBOOTFIXUPS 634 ---help--- 635 This option is needed for RDC R-321x system-on-chip, also known 636 as R-8610-(G). 637 If you don't have one of these chips, you should say N here. 638 639config X86_32_NON_STANDARD 640 bool "Support non-standard 32-bit SMP architectures" 641 depends on X86_32 && SMP 642 depends on X86_EXTENDED_PLATFORM 643 ---help--- 644 This option compiles in the bigsmp and STA2X11 default 645 subarchitectures. It is intended for a generic binary 646 kernel. If you select them all, kernel will probe it one by 647 one and will fallback to default. 648 649# Alphabetically sorted list of Non standard 32 bit platforms 650 651config X86_SUPPORTS_MEMORY_FAILURE 652 def_bool y 653 # MCE code calls memory_failure(): 654 depends on X86_MCE 655 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 656 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 657 depends on X86_64 || !SPARSEMEM 658 select ARCH_SUPPORTS_MEMORY_FAILURE 659 660config STA2X11 661 bool "STA2X11 Companion Chip Support" 662 depends on X86_32_NON_STANDARD && PCI 663 select X86_DEV_DMA_OPS 664 select X86_DMA_REMAP 665 select SWIOTLB 666 select MFD_STA2X11 667 select GPIOLIB 668 default n 669 ---help--- 670 This adds support for boards based on the STA2X11 IO-Hub, 671 a.k.a. "ConneXt". The chip is used in place of the standard 672 PC chipset, so all "standard" peripherals are missing. If this 673 option is selected the kernel will still be able to boot on 674 standard PC machines. 675 676config X86_32_IRIS 677 tristate "Eurobraille/Iris poweroff module" 678 depends on X86_32 679 ---help--- 680 The Iris machines from EuroBraille do not have APM or ACPI support 681 to shut themselves down properly. A special I/O sequence is 682 needed to do so, which is what this module does at 683 kernel shutdown. 684 685 This is only for Iris machines from EuroBraille. 686 687 If unused, say N. 688 689config SCHED_OMIT_FRAME_POINTER 690 def_bool y 691 prompt "Single-depth WCHAN output" 692 depends on X86 693 ---help--- 694 Calculate simpler /proc/<PID>/wchan values. If this option 695 is disabled then wchan values will recurse back to the 696 caller function. This provides more accurate wchan values, 697 at the expense of slightly more scheduling overhead. 698 699 If in doubt, say "Y". 700 701menuconfig HYPERVISOR_GUEST 702 bool "Linux guest support" 703 ---help--- 704 Say Y here to enable options for running Linux under various hyper- 705 visors. This option enables basic hypervisor detection and platform 706 setup. 707 708 If you say N, all options in this submenu will be skipped and 709 disabled, and Linux guest support won't be built in. 710 711if HYPERVISOR_GUEST 712 713config PARAVIRT 714 bool "Enable paravirtualization code" 715 ---help--- 716 This changes the kernel so it can modify itself when it is run 717 under a hypervisor, potentially improving performance significantly 718 over full virtualization. However, when run without a hypervisor 719 the kernel is theoretically slower and slightly larger. 720 721config PARAVIRT_DEBUG 722 bool "paravirt-ops debugging" 723 depends on PARAVIRT && DEBUG_KERNEL 724 ---help--- 725 Enable to debug paravirt_ops internals. Specifically, BUG if 726 a paravirt_op is missing when it is called. 727 728config PARAVIRT_SPINLOCKS 729 bool "Paravirtualization layer for spinlocks" 730 depends on PARAVIRT && SMP 731 ---help--- 732 Paravirtualized spinlocks allow a pvops backend to replace the 733 spinlock implementation with something virtualization-friendly 734 (for example, block the virtual CPU rather than spinning). 735 736 It has a minimal impact on native kernels and gives a nice performance 737 benefit on paravirtualized KVM / Xen kernels. 738 739 If you are unsure how to answer this question, answer Y. 740 741config QUEUED_LOCK_STAT 742 bool "Paravirt queued spinlock statistics" 743 depends on PARAVIRT_SPINLOCKS && DEBUG_FS 744 ---help--- 745 Enable the collection of statistical data on the slowpath 746 behavior of paravirtualized queued spinlocks and report 747 them on debugfs. 748 749source "arch/x86/xen/Kconfig" 750 751config KVM_GUEST 752 bool "KVM Guest support (including kvmclock)" 753 depends on PARAVIRT 754 select PARAVIRT_CLOCK 755 default y 756 ---help--- 757 This option enables various optimizations for running under the KVM 758 hypervisor. It includes a paravirtualized clock, so that instead 759 of relying on a PIT (or probably other) emulation by the 760 underlying device model, the host provides the guest with 761 timing infrastructure such as time of day, and system time 762 763config KVM_DEBUG_FS 764 bool "Enable debug information for KVM Guests in debugfs" 765 depends on KVM_GUEST && DEBUG_FS 766 default n 767 ---help--- 768 This option enables collection of various statistics for KVM guest. 769 Statistics are displayed in debugfs filesystem. Enabling this option 770 may incur significant overhead. 771 772source "arch/x86/lguest/Kconfig" 773 774config PARAVIRT_TIME_ACCOUNTING 775 bool "Paravirtual steal time accounting" 776 depends on PARAVIRT 777 default n 778 ---help--- 779 Select this option to enable fine granularity task steal time 780 accounting. Time spent executing other tasks in parallel with 781 the current vCPU is discounted from the vCPU power. To account for 782 that, there can be a small performance impact. 783 784 If in doubt, say N here. 785 786config PARAVIRT_CLOCK 787 bool 788 789endif #HYPERVISOR_GUEST 790 791config NO_BOOTMEM 792 def_bool y 793 794source "arch/x86/Kconfig.cpu" 795 796config HPET_TIMER 797 def_bool X86_64 798 prompt "HPET Timer Support" if X86_32 799 ---help--- 800 Use the IA-PC HPET (High Precision Event Timer) to manage 801 time in preference to the PIT and RTC, if a HPET is 802 present. 803 HPET is the next generation timer replacing legacy 8254s. 804 The HPET provides a stable time base on SMP 805 systems, unlike the TSC, but it is more expensive to access, 806 as it is off-chip. The interface used is documented 807 in the HPET spec, revision 1. 808 809 You can safely choose Y here. However, HPET will only be 810 activated if the platform and the BIOS support this feature. 811 Otherwise the 8254 will be used for timing services. 812 813 Choose N to continue using the legacy 8254 timer. 814 815config HPET_EMULATE_RTC 816 def_bool y 817 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 818 819config APB_TIMER 820 def_bool y if X86_INTEL_MID 821 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 822 select DW_APB_TIMER 823 depends on X86_INTEL_MID && SFI 824 help 825 APB timer is the replacement for 8254, HPET on X86 MID platforms. 826 The APBT provides a stable time base on SMP 827 systems, unlike the TSC, but it is more expensive to access, 828 as it is off-chip. APB timers are always running regardless of CPU 829 C states, they are used as per CPU clockevent device when possible. 830 831# Mark as expert because too many people got it wrong. 832# The code disables itself when not needed. 833config DMI 834 default y 835 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 836 bool "Enable DMI scanning" if EXPERT 837 ---help--- 838 Enabled scanning of DMI to identify machine quirks. Say Y 839 here unless you have verified that your setup is not 840 affected by entries in the DMI blacklist. Required by PNP 841 BIOS code. 842 843config GART_IOMMU 844 bool "Old AMD GART IOMMU support" 845 select SWIOTLB 846 depends on X86_64 && PCI && AMD_NB 847 ---help--- 848 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 849 GART based hardware IOMMUs. 850 851 The GART supports full DMA access for devices with 32-bit access 852 limitations, on systems with more than 3 GB. This is usually needed 853 for USB, sound, many IDE/SATA chipsets and some other devices. 854 855 Newer systems typically have a modern AMD IOMMU, supported via 856 the CONFIG_AMD_IOMMU=y config option. 857 858 In normal configurations this driver is only active when needed: 859 there's more than 3 GB of memory and the system contains a 860 32-bit limited device. 861 862 If unsure, say Y. 863 864config CALGARY_IOMMU 865 bool "IBM Calgary IOMMU support" 866 select SWIOTLB 867 depends on X86_64 && PCI 868 ---help--- 869 Support for hardware IOMMUs in IBM's xSeries x366 and x460 870 systems. Needed to run systems with more than 3GB of memory 871 properly with 32-bit PCI devices that do not support DAC 872 (Double Address Cycle). Calgary also supports bus level 873 isolation, where all DMAs pass through the IOMMU. This 874 prevents them from going anywhere except their intended 875 destination. This catches hard-to-find kernel bugs and 876 mis-behaving drivers and devices that do not use the DMA-API 877 properly to set up their DMA buffers. The IOMMU can be 878 turned off at boot time with the iommu=off parameter. 879 Normally the kernel will make the right choice by itself. 880 If unsure, say Y. 881 882config CALGARY_IOMMU_ENABLED_BY_DEFAULT 883 def_bool y 884 prompt "Should Calgary be enabled by default?" 885 depends on CALGARY_IOMMU 886 ---help--- 887 Should Calgary be enabled by default? if you choose 'y', Calgary 888 will be used (if it exists). If you choose 'n', Calgary will not be 889 used even if it exists. If you choose 'n' and would like to use 890 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 891 If unsure, say Y. 892 893# need this always selected by IOMMU for the VIA workaround 894config SWIOTLB 895 def_bool y if X86_64 896 ---help--- 897 Support for software bounce buffers used on x86-64 systems 898 which don't have a hardware IOMMU. Using this PCI devices 899 which can only access 32-bits of memory can be used on systems 900 with more than 3 GB of memory. 901 If unsure, say Y. 902 903config IOMMU_HELPER 904 def_bool y 905 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 906 907config MAXSMP 908 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 909 depends on X86_64 && SMP && DEBUG_KERNEL 910 select CPUMASK_OFFSTACK 911 ---help--- 912 Enable maximum number of CPUS and NUMA Nodes for this architecture. 913 If unsure, say N. 914 915config NR_CPUS 916 int "Maximum number of CPUs" if SMP && !MAXSMP 917 range 2 8 if SMP && X86_32 && !X86_BIGSMP 918 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 919 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 920 default "1" if !SMP 921 default "8192" if MAXSMP 922 default "32" if SMP && X86_BIGSMP 923 default "8" if SMP && X86_32 924 default "64" if SMP 925 ---help--- 926 This allows you to specify the maximum number of CPUs which this 927 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 928 supported value is 8192, otherwise the maximum value is 512. The 929 minimum value which makes sense is 2. 930 931 This is purely to save memory - each supported CPU adds 932 approximately eight kilobytes to the kernel image. 933 934config SCHED_SMT 935 bool "SMT (Hyperthreading) scheduler support" 936 depends on SMP 937 ---help--- 938 SMT scheduler support improves the CPU scheduler's decision making 939 when dealing with Intel Pentium 4 chips with HyperThreading at a 940 cost of slightly increased overhead in some places. If unsure say 941 N here. 942 943config SCHED_MC 944 def_bool y 945 prompt "Multi-core scheduler support" 946 depends on SMP 947 ---help--- 948 Multi-core scheduler support improves the CPU scheduler's decision 949 making when dealing with multi-core CPU chips at a cost of slightly 950 increased overhead in some places. If unsure say N here. 951 952config SCHED_MC_PRIO 953 bool "CPU core priorities scheduler support" 954 depends on SCHED_MC && CPU_SUP_INTEL 955 select X86_INTEL_PSTATE 956 select CPU_FREQ 957 default y 958 ---help--- 959 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 960 core ordering determined at manufacturing time, which allows 961 certain cores to reach higher turbo frequencies (when running 962 single threaded workloads) than others. 963 964 Enabling this kernel feature teaches the scheduler about 965 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 966 scheduler's CPU selection logic accordingly, so that higher 967 overall system performance can be achieved. 968 969 This feature will have no effect on CPUs without this feature. 970 971 If unsure say Y here. 972 973source "kernel/Kconfig.preempt" 974 975config UP_LATE_INIT 976 def_bool y 977 depends on !SMP && X86_LOCAL_APIC 978 979config X86_UP_APIC 980 bool "Local APIC support on uniprocessors" if !PCI_MSI 981 default PCI_MSI 982 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 983 ---help--- 984 A local APIC (Advanced Programmable Interrupt Controller) is an 985 integrated interrupt controller in the CPU. If you have a single-CPU 986 system which has a processor with a local APIC, you can say Y here to 987 enable and use it. If you say Y here even though your machine doesn't 988 have a local APIC, then the kernel will still run with no slowdown at 989 all. The local APIC supports CPU-generated self-interrupts (timer, 990 performance counters), and the NMI watchdog which detects hard 991 lockups. 992 993config X86_UP_IOAPIC 994 bool "IO-APIC support on uniprocessors" 995 depends on X86_UP_APIC 996 ---help--- 997 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 998 SMP-capable replacement for PC-style interrupt controllers. Most 999 SMP systems and many recent uniprocessor systems have one. 1000 1001 If you have a single-CPU system with an IO-APIC, you can say Y here 1002 to use it. If you say Y here even though your machine doesn't have 1003 an IO-APIC, then the kernel will still run with no slowdown at all. 1004 1005config X86_LOCAL_APIC 1006 def_bool y 1007 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1008 select IRQ_DOMAIN_HIERARCHY 1009 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1010 1011config X86_IO_APIC 1012 def_bool y 1013 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1014 1015config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 1016 bool "Reroute for broken boot IRQs" 1017 depends on X86_IO_APIC 1018 ---help--- 1019 This option enables a workaround that fixes a source of 1020 spurious interrupts. This is recommended when threaded 1021 interrupt handling is used on systems where the generation of 1022 superfluous "boot interrupts" cannot be disabled. 1023 1024 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 1025 entry in the chipset's IO-APIC is masked (as, e.g. the RT 1026 kernel does during interrupt handling). On chipsets where this 1027 boot IRQ generation cannot be disabled, this workaround keeps 1028 the original IRQ line masked so that only the equivalent "boot 1029 IRQ" is delivered to the CPUs. The workaround also tells the 1030 kernel to set up the IRQ handler on the boot IRQ line. In this 1031 way only one interrupt is delivered to the kernel. Otherwise 1032 the spurious second interrupt may cause the kernel to bring 1033 down (vital) interrupt lines. 1034 1035 Only affects "broken" chipsets. Interrupt sharing may be 1036 increased on these systems. 1037 1038config X86_MCE 1039 bool "Machine Check / overheating reporting" 1040 select GENERIC_ALLOCATOR 1041 default y 1042 ---help--- 1043 Machine Check support allows the processor to notify the 1044 kernel if it detects a problem (e.g. overheating, data corruption). 1045 The action the kernel takes depends on the severity of the problem, 1046 ranging from warning messages to halting the machine. 1047 1048config X86_MCELOG_LEGACY 1049 bool "Support for deprecated /dev/mcelog character device" 1050 depends on X86_MCE 1051 ---help--- 1052 Enable support for /dev/mcelog which is needed by the old mcelog 1053 userspace logging daemon. Consider switching to the new generation 1054 rasdaemon solution. 1055 1056config X86_MCE_INTEL 1057 def_bool y 1058 prompt "Intel MCE features" 1059 depends on X86_MCE && X86_LOCAL_APIC 1060 ---help--- 1061 Additional support for intel specific MCE features such as 1062 the thermal monitor. 1063 1064config X86_MCE_AMD 1065 def_bool y 1066 prompt "AMD MCE features" 1067 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 1068 ---help--- 1069 Additional support for AMD specific MCE features such as 1070 the DRAM Error Threshold. 1071 1072config X86_ANCIENT_MCE 1073 bool "Support for old Pentium 5 / WinChip machine checks" 1074 depends on X86_32 && X86_MCE 1075 ---help--- 1076 Include support for machine check handling on old Pentium 5 or WinChip 1077 systems. These typically need to be enabled explicitly on the command 1078 line. 1079 1080config X86_MCE_THRESHOLD 1081 depends on X86_MCE_AMD || X86_MCE_INTEL 1082 def_bool y 1083 1084config X86_MCE_INJECT 1085 depends on X86_MCE && X86_LOCAL_APIC && X86_MCELOG_LEGACY 1086 tristate "Machine check injector support" 1087 ---help--- 1088 Provide support for injecting machine checks for testing purposes. 1089 If you don't know what a machine check is and you don't do kernel 1090 QA it is safe to say n. 1091 1092config X86_THERMAL_VECTOR 1093 def_bool y 1094 depends on X86_MCE_INTEL 1095 1096source "arch/x86/events/Kconfig" 1097 1098config X86_LEGACY_VM86 1099 bool "Legacy VM86 support" 1100 default n 1101 depends on X86_32 1102 ---help--- 1103 This option allows user programs to put the CPU into V8086 1104 mode, which is an 80286-era approximation of 16-bit real mode. 1105 1106 Some very old versions of X and/or vbetool require this option 1107 for user mode setting. Similarly, DOSEMU will use it if 1108 available to accelerate real mode DOS programs. However, any 1109 recent version of DOSEMU, X, or vbetool should be fully 1110 functional even without kernel VM86 support, as they will all 1111 fall back to software emulation. Nevertheless, if you are using 1112 a 16-bit DOS program where 16-bit performance matters, vm86 1113 mode might be faster than emulation and you might want to 1114 enable this option. 1115 1116 Note that any app that works on a 64-bit kernel is unlikely to 1117 need this option, as 64-bit kernels don't, and can't, support 1118 V8086 mode. This option is also unrelated to 16-bit protected 1119 mode and is not needed to run most 16-bit programs under Wine. 1120 1121 Enabling this option increases the complexity of the kernel 1122 and slows down exception handling a tiny bit. 1123 1124 If unsure, say N here. 1125 1126config VM86 1127 bool 1128 default X86_LEGACY_VM86 1129 1130config X86_16BIT 1131 bool "Enable support for 16-bit segments" if EXPERT 1132 default y 1133 depends on MODIFY_LDT_SYSCALL 1134 ---help--- 1135 This option is required by programs like Wine to run 16-bit 1136 protected mode legacy code on x86 processors. Disabling 1137 this option saves about 300 bytes on i386, or around 6K text 1138 plus 16K runtime memory on x86-64, 1139 1140config X86_ESPFIX32 1141 def_bool y 1142 depends on X86_16BIT && X86_32 1143 1144config X86_ESPFIX64 1145 def_bool y 1146 depends on X86_16BIT && X86_64 1147 1148config X86_VSYSCALL_EMULATION 1149 bool "Enable vsyscall emulation" if EXPERT 1150 default y 1151 depends on X86_64 1152 ---help--- 1153 This enables emulation of the legacy vsyscall page. Disabling 1154 it is roughly equivalent to booting with vsyscall=none, except 1155 that it will also disable the helpful warning if a program 1156 tries to use a vsyscall. With this option set to N, offending 1157 programs will just segfault, citing addresses of the form 1158 0xffffffffff600?00. 1159 1160 This option is required by many programs built before 2013, and 1161 care should be used even with newer programs if set to N. 1162 1163 Disabling this option saves about 7K of kernel size and 1164 possibly 4K of additional runtime pagetable memory. 1165 1166config TOSHIBA 1167 tristate "Toshiba Laptop support" 1168 depends on X86_32 1169 ---help--- 1170 This adds a driver to safely access the System Management Mode of 1171 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1172 not work on models with a Phoenix BIOS. The System Management Mode 1173 is used to set the BIOS and power saving options on Toshiba portables. 1174 1175 For information on utilities to make use of this driver see the 1176 Toshiba Linux utilities web site at: 1177 <http://www.buzzard.org.uk/toshiba/>. 1178 1179 Say Y if you intend to run this kernel on a Toshiba portable. 1180 Say N otherwise. 1181 1182config I8K 1183 tristate "Dell i8k legacy laptop support" 1184 select HWMON 1185 select SENSORS_DELL_SMM 1186 ---help--- 1187 This option enables legacy /proc/i8k userspace interface in hwmon 1188 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1189 temperature and allows controlling fan speeds of Dell laptops via 1190 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1191 it reports also power and hotkey status. For fan speed control is 1192 needed userspace package i8kutils. 1193 1194 Say Y if you intend to run this kernel on old Dell laptops or want to 1195 use userspace package i8kutils. 1196 Say N otherwise. 1197 1198config X86_REBOOTFIXUPS 1199 bool "Enable X86 board specific fixups for reboot" 1200 depends on X86_32 1201 ---help--- 1202 This enables chipset and/or board specific fixups to be done 1203 in order to get reboot to work correctly. This is only needed on 1204 some combinations of hardware and BIOS. The symptom, for which 1205 this config is intended, is when reboot ends with a stalled/hung 1206 system. 1207 1208 Currently, the only fixup is for the Geode machines using 1209 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1210 1211 Say Y if you want to enable the fixup. Currently, it's safe to 1212 enable this option even if you don't need it. 1213 Say N otherwise. 1214 1215config MICROCODE 1216 bool "CPU microcode loading support" 1217 default y 1218 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1219 select FW_LOADER 1220 ---help--- 1221 If you say Y here, you will be able to update the microcode on 1222 Intel and AMD processors. The Intel support is for the IA32 family, 1223 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1224 AMD support is for families 0x10 and later. You will obviously need 1225 the actual microcode binary data itself which is not shipped with 1226 the Linux kernel. 1227 1228 The preferred method to load microcode from a detached initrd is described 1229 in Documentation/x86/early-microcode.txt. For that you need to enable 1230 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1231 initrd for microcode blobs. 1232 1233 In addition, you can build-in the microcode into the kernel. For that you 1234 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 1235 to the CONFIG_EXTRA_FIRMWARE config option. 1236 1237config MICROCODE_INTEL 1238 bool "Intel microcode loading support" 1239 depends on MICROCODE 1240 default MICROCODE 1241 select FW_LOADER 1242 ---help--- 1243 This options enables microcode patch loading support for Intel 1244 processors. 1245 1246 For the current Intel microcode data package go to 1247 <https://downloadcenter.intel.com> and search for 1248 'Linux Processor Microcode Data File'. 1249 1250config MICROCODE_AMD 1251 bool "AMD microcode loading support" 1252 depends on MICROCODE 1253 select FW_LOADER 1254 ---help--- 1255 If you select this option, microcode patch loading support for AMD 1256 processors will be enabled. 1257 1258config MICROCODE_OLD_INTERFACE 1259 def_bool y 1260 depends on MICROCODE 1261 1262config X86_MSR 1263 tristate "/dev/cpu/*/msr - Model-specific register support" 1264 ---help--- 1265 This device gives privileged processes access to the x86 1266 Model-Specific Registers (MSRs). It is a character device with 1267 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1268 MSR accesses are directed to a specific CPU on multi-processor 1269 systems. 1270 1271config X86_CPUID 1272 tristate "/dev/cpu/*/cpuid - CPU information support" 1273 ---help--- 1274 This device gives processes access to the x86 CPUID instruction to 1275 be executed on a specific processor. It is a character device 1276 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1277 /dev/cpu/31/cpuid. 1278 1279choice 1280 prompt "High Memory Support" 1281 default HIGHMEM4G 1282 depends on X86_32 1283 1284config NOHIGHMEM 1285 bool "off" 1286 ---help--- 1287 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1288 However, the address space of 32-bit x86 processors is only 4 1289 Gigabytes large. That means that, if you have a large amount of 1290 physical memory, not all of it can be "permanently mapped" by the 1291 kernel. The physical memory that's not permanently mapped is called 1292 "high memory". 1293 1294 If you are compiling a kernel which will never run on a machine with 1295 more than 1 Gigabyte total physical RAM, answer "off" here (default 1296 choice and suitable for most users). This will result in a "3GB/1GB" 1297 split: 3GB are mapped so that each process sees a 3GB virtual memory 1298 space and the remaining part of the 4GB virtual memory space is used 1299 by the kernel to permanently map as much physical memory as 1300 possible. 1301 1302 If the machine has between 1 and 4 Gigabytes physical RAM, then 1303 answer "4GB" here. 1304 1305 If more than 4 Gigabytes is used then answer "64GB" here. This 1306 selection turns Intel PAE (Physical Address Extension) mode on. 1307 PAE implements 3-level paging on IA32 processors. PAE is fully 1308 supported by Linux, PAE mode is implemented on all recent Intel 1309 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1310 then the kernel will not boot on CPUs that don't support PAE! 1311 1312 The actual amount of total physical memory will either be 1313 auto detected or can be forced by using a kernel command line option 1314 such as "mem=256M". (Try "man bootparam" or see the documentation of 1315 your boot loader (lilo or loadlin) about how to pass options to the 1316 kernel at boot time.) 1317 1318 If unsure, say "off". 1319 1320config HIGHMEM4G 1321 bool "4GB" 1322 ---help--- 1323 Select this if you have a 32-bit processor and between 1 and 4 1324 gigabytes of physical RAM. 1325 1326config HIGHMEM64G 1327 bool "64GB" 1328 depends on !M486 1329 select X86_PAE 1330 ---help--- 1331 Select this if you have a 32-bit processor and more than 4 1332 gigabytes of physical RAM. 1333 1334endchoice 1335 1336choice 1337 prompt "Memory split" if EXPERT 1338 default VMSPLIT_3G 1339 depends on X86_32 1340 ---help--- 1341 Select the desired split between kernel and user memory. 1342 1343 If the address range available to the kernel is less than the 1344 physical memory installed, the remaining memory will be available 1345 as "high memory". Accessing high memory is a little more costly 1346 than low memory, as it needs to be mapped into the kernel first. 1347 Note that increasing the kernel address space limits the range 1348 available to user programs, making the address space there 1349 tighter. Selecting anything other than the default 3G/1G split 1350 will also likely make your kernel incompatible with binary-only 1351 kernel modules. 1352 1353 If you are not absolutely sure what you are doing, leave this 1354 option alone! 1355 1356 config VMSPLIT_3G 1357 bool "3G/1G user/kernel split" 1358 config VMSPLIT_3G_OPT 1359 depends on !X86_PAE 1360 bool "3G/1G user/kernel split (for full 1G low memory)" 1361 config VMSPLIT_2G 1362 bool "2G/2G user/kernel split" 1363 config VMSPLIT_2G_OPT 1364 depends on !X86_PAE 1365 bool "2G/2G user/kernel split (for full 2G low memory)" 1366 config VMSPLIT_1G 1367 bool "1G/3G user/kernel split" 1368endchoice 1369 1370config PAGE_OFFSET 1371 hex 1372 default 0xB0000000 if VMSPLIT_3G_OPT 1373 default 0x80000000 if VMSPLIT_2G 1374 default 0x78000000 if VMSPLIT_2G_OPT 1375 default 0x40000000 if VMSPLIT_1G 1376 default 0xC0000000 1377 depends on X86_32 1378 1379config HIGHMEM 1380 def_bool y 1381 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1382 1383config X86_PAE 1384 bool "PAE (Physical Address Extension) Support" 1385 depends on X86_32 && !HIGHMEM4G 1386 select SWIOTLB 1387 ---help--- 1388 PAE is required for NX support, and furthermore enables 1389 larger swapspace support for non-overcommit purposes. It 1390 has the cost of more pagetable lookup overhead, and also 1391 consumes more pagetable space per process. 1392 1393config ARCH_PHYS_ADDR_T_64BIT 1394 def_bool y 1395 depends on X86_64 || X86_PAE 1396 1397config ARCH_DMA_ADDR_T_64BIT 1398 def_bool y 1399 depends on X86_64 || HIGHMEM64G 1400 1401config X86_DIRECT_GBPAGES 1402 def_bool y 1403 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1404 ---help--- 1405 Certain kernel features effectively disable kernel 1406 linear 1 GB mappings (even if the CPU otherwise 1407 supports them), so don't confuse the user by printing 1408 that we have them enabled. 1409 1410# Common NUMA Features 1411config NUMA 1412 bool "Numa Memory Allocation and Scheduler Support" 1413 depends on SMP 1414 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1415 default y if X86_BIGSMP 1416 ---help--- 1417 Enable NUMA (Non Uniform Memory Access) support. 1418 1419 The kernel will try to allocate memory used by a CPU on the 1420 local memory controller of the CPU and add some more 1421 NUMA awareness to the kernel. 1422 1423 For 64-bit this is recommended if the system is Intel Core i7 1424 (or later), AMD Opteron, or EM64T NUMA. 1425 1426 For 32-bit this is only needed if you boot a 32-bit 1427 kernel on a 64-bit NUMA platform. 1428 1429 Otherwise, you should say N. 1430 1431config AMD_NUMA 1432 def_bool y 1433 prompt "Old style AMD Opteron NUMA detection" 1434 depends on X86_64 && NUMA && PCI 1435 ---help--- 1436 Enable AMD NUMA node topology detection. You should say Y here if 1437 you have a multi processor AMD system. This uses an old method to 1438 read the NUMA configuration directly from the builtin Northbridge 1439 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1440 which also takes priority if both are compiled in. 1441 1442config X86_64_ACPI_NUMA 1443 def_bool y 1444 prompt "ACPI NUMA detection" 1445 depends on X86_64 && NUMA && ACPI && PCI 1446 select ACPI_NUMA 1447 ---help--- 1448 Enable ACPI SRAT based node topology detection. 1449 1450# Some NUMA nodes have memory ranges that span 1451# other nodes. Even though a pfn is valid and 1452# between a node's start and end pfns, it may not 1453# reside on that node. See memmap_init_zone() 1454# for details. 1455config NODES_SPAN_OTHER_NODES 1456 def_bool y 1457 depends on X86_64_ACPI_NUMA 1458 1459config NUMA_EMU 1460 bool "NUMA emulation" 1461 depends on NUMA 1462 ---help--- 1463 Enable NUMA emulation. A flat machine will be split 1464 into virtual nodes when booted with "numa=fake=N", where N is the 1465 number of nodes. This is only useful for debugging. 1466 1467config NODES_SHIFT 1468 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1469 range 1 10 1470 default "10" if MAXSMP 1471 default "6" if X86_64 1472 default "3" 1473 depends on NEED_MULTIPLE_NODES 1474 ---help--- 1475 Specify the maximum number of NUMA Nodes available on the target 1476 system. Increases memory reserved to accommodate various tables. 1477 1478config ARCH_HAVE_MEMORY_PRESENT 1479 def_bool y 1480 depends on X86_32 && DISCONTIGMEM 1481 1482config NEED_NODE_MEMMAP_SIZE 1483 def_bool y 1484 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1485 1486config ARCH_FLATMEM_ENABLE 1487 def_bool y 1488 depends on X86_32 && !NUMA 1489 1490config ARCH_DISCONTIGMEM_ENABLE 1491 def_bool y 1492 depends on NUMA && X86_32 1493 1494config ARCH_DISCONTIGMEM_DEFAULT 1495 def_bool y 1496 depends on NUMA && X86_32 1497 1498config ARCH_SPARSEMEM_ENABLE 1499 def_bool y 1500 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1501 select SPARSEMEM_STATIC if X86_32 1502 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1503 1504config ARCH_SPARSEMEM_DEFAULT 1505 def_bool y 1506 depends on X86_64 1507 1508config ARCH_SELECT_MEMORY_MODEL 1509 def_bool y 1510 depends on ARCH_SPARSEMEM_ENABLE 1511 1512config ARCH_MEMORY_PROBE 1513 bool "Enable sysfs memory/probe interface" 1514 depends on X86_64 && MEMORY_HOTPLUG 1515 help 1516 This option enables a sysfs memory/probe interface for testing. 1517 See Documentation/memory-hotplug.txt for more information. 1518 If you are unsure how to answer this question, answer N. 1519 1520config ARCH_PROC_KCORE_TEXT 1521 def_bool y 1522 depends on X86_64 && PROC_KCORE 1523 1524config ILLEGAL_POINTER_VALUE 1525 hex 1526 default 0 if X86_32 1527 default 0xdead000000000000 if X86_64 1528 1529source "mm/Kconfig" 1530 1531config X86_PMEM_LEGACY_DEVICE 1532 bool 1533 1534config X86_PMEM_LEGACY 1535 tristate "Support non-standard NVDIMMs and ADR protected memory" 1536 depends on PHYS_ADDR_T_64BIT 1537 depends on BLK_DEV 1538 select X86_PMEM_LEGACY_DEVICE 1539 select LIBNVDIMM 1540 help 1541 Treat memory marked using the non-standard e820 type of 12 as used 1542 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1543 The kernel will offer these regions to the 'pmem' driver so 1544 they can be used for persistent storage. 1545 1546 Say Y if unsure. 1547 1548config HIGHPTE 1549 bool "Allocate 3rd-level pagetables from highmem" 1550 depends on HIGHMEM 1551 ---help--- 1552 The VM uses one page table entry for each page of physical memory. 1553 For systems with a lot of RAM, this can be wasteful of precious 1554 low memory. Setting this option will put user-space page table 1555 entries in high memory. 1556 1557config X86_CHECK_BIOS_CORRUPTION 1558 bool "Check for low memory corruption" 1559 ---help--- 1560 Periodically check for memory corruption in low memory, which 1561 is suspected to be caused by BIOS. Even when enabled in the 1562 configuration, it is disabled at runtime. Enable it by 1563 setting "memory_corruption_check=1" on the kernel command 1564 line. By default it scans the low 64k of memory every 60 1565 seconds; see the memory_corruption_check_size and 1566 memory_corruption_check_period parameters in 1567 Documentation/admin-guide/kernel-parameters.rst to adjust this. 1568 1569 When enabled with the default parameters, this option has 1570 almost no overhead, as it reserves a relatively small amount 1571 of memory and scans it infrequently. It both detects corruption 1572 and prevents it from affecting the running system. 1573 1574 It is, however, intended as a diagnostic tool; if repeatable 1575 BIOS-originated corruption always affects the same memory, 1576 you can use memmap= to prevent the kernel from using that 1577 memory. 1578 1579config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1580 bool "Set the default setting of memory_corruption_check" 1581 depends on X86_CHECK_BIOS_CORRUPTION 1582 default y 1583 ---help--- 1584 Set whether the default state of memory_corruption_check is 1585 on or off. 1586 1587config X86_RESERVE_LOW 1588 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1589 default 64 1590 range 4 640 1591 ---help--- 1592 Specify the amount of low memory to reserve for the BIOS. 1593 1594 The first page contains BIOS data structures that the kernel 1595 must not use, so that page must always be reserved. 1596 1597 By default we reserve the first 64K of physical RAM, as a 1598 number of BIOSes are known to corrupt that memory range 1599 during events such as suspend/resume or monitor cable 1600 insertion, so it must not be used by the kernel. 1601 1602 You can set this to 4 if you are absolutely sure that you 1603 trust the BIOS to get all its memory reservations and usages 1604 right. If you know your BIOS have problems beyond the 1605 default 64K area, you can set this to 640 to avoid using the 1606 entire low memory range. 1607 1608 If you have doubts about the BIOS (e.g. suspend/resume does 1609 not work or there's kernel crashes after certain hardware 1610 hotplug events) then you might want to enable 1611 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1612 typical corruption patterns. 1613 1614 Leave this to the default value of 64 if you are unsure. 1615 1616config MATH_EMULATION 1617 bool 1618 depends on MODIFY_LDT_SYSCALL 1619 prompt "Math emulation" if X86_32 1620 ---help--- 1621 Linux can emulate a math coprocessor (used for floating point 1622 operations) if you don't have one. 486DX and Pentium processors have 1623 a math coprocessor built in, 486SX and 386 do not, unless you added 1624 a 487DX or 387, respectively. (The messages during boot time can 1625 give you some hints here ["man dmesg"].) Everyone needs either a 1626 coprocessor or this emulation. 1627 1628 If you don't have a math coprocessor, you need to say Y here; if you 1629 say Y here even though you have a coprocessor, the coprocessor will 1630 be used nevertheless. (This behavior can be changed with the kernel 1631 command line option "no387", which comes handy if your coprocessor 1632 is broken. Try "man bootparam" or see the documentation of your boot 1633 loader (lilo or loadlin) about how to pass options to the kernel at 1634 boot time.) This means that it is a good idea to say Y here if you 1635 intend to use this kernel on different machines. 1636 1637 More information about the internals of the Linux math coprocessor 1638 emulation can be found in <file:arch/x86/math-emu/README>. 1639 1640 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1641 kernel, it won't hurt. 1642 1643config MTRR 1644 def_bool y 1645 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1646 ---help--- 1647 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1648 the Memory Type Range Registers (MTRRs) may be used to control 1649 processor access to memory ranges. This is most useful if you have 1650 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1651 allows bus write transfers to be combined into a larger transfer 1652 before bursting over the PCI/AGP bus. This can increase performance 1653 of image write operations 2.5 times or more. Saying Y here creates a 1654 /proc/mtrr file which may be used to manipulate your processor's 1655 MTRRs. Typically the X server should use this. 1656 1657 This code has a reasonably generic interface so that similar 1658 control registers on other processors can be easily supported 1659 as well: 1660 1661 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1662 Registers (ARRs) which provide a similar functionality to MTRRs. For 1663 these, the ARRs are used to emulate the MTRRs. 1664 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1665 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1666 write-combining. All of these processors are supported by this code 1667 and it makes sense to say Y here if you have one of them. 1668 1669 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1670 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1671 can lead to all sorts of problems, so it's good to say Y here. 1672 1673 You can safely say Y even if your machine doesn't have MTRRs, you'll 1674 just add about 9 KB to your kernel. 1675 1676 See <file:Documentation/x86/mtrr.txt> for more information. 1677 1678config MTRR_SANITIZER 1679 def_bool y 1680 prompt "MTRR cleanup support" 1681 depends on MTRR 1682 ---help--- 1683 Convert MTRR layout from continuous to discrete, so X drivers can 1684 add writeback entries. 1685 1686 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1687 The largest mtrr entry size for a continuous block can be set with 1688 mtrr_chunk_size. 1689 1690 If unsure, say Y. 1691 1692config MTRR_SANITIZER_ENABLE_DEFAULT 1693 int "MTRR cleanup enable value (0-1)" 1694 range 0 1 1695 default "0" 1696 depends on MTRR_SANITIZER 1697 ---help--- 1698 Enable mtrr cleanup default value 1699 1700config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1701 int "MTRR cleanup spare reg num (0-7)" 1702 range 0 7 1703 default "1" 1704 depends on MTRR_SANITIZER 1705 ---help--- 1706 mtrr cleanup spare entries default, it can be changed via 1707 mtrr_spare_reg_nr=N on the kernel command line. 1708 1709config X86_PAT 1710 def_bool y 1711 prompt "x86 PAT support" if EXPERT 1712 depends on MTRR 1713 ---help--- 1714 Use PAT attributes to setup page level cache control. 1715 1716 PATs are the modern equivalents of MTRRs and are much more 1717 flexible than MTRRs. 1718 1719 Say N here if you see bootup problems (boot crash, boot hang, 1720 spontaneous reboots) or a non-working video driver. 1721 1722 If unsure, say Y. 1723 1724config ARCH_USES_PG_UNCACHED 1725 def_bool y 1726 depends on X86_PAT 1727 1728config ARCH_RANDOM 1729 def_bool y 1730 prompt "x86 architectural random number generator" if EXPERT 1731 ---help--- 1732 Enable the x86 architectural RDRAND instruction 1733 (Intel Bull Mountain technology) to generate random numbers. 1734 If supported, this is a high bandwidth, cryptographically 1735 secure hardware random number generator. 1736 1737config X86_SMAP 1738 def_bool y 1739 prompt "Supervisor Mode Access Prevention" if EXPERT 1740 ---help--- 1741 Supervisor Mode Access Prevention (SMAP) is a security 1742 feature in newer Intel processors. There is a small 1743 performance cost if this enabled and turned on; there is 1744 also a small increase in the kernel size if this is enabled. 1745 1746 If unsure, say Y. 1747 1748config X86_INTEL_MPX 1749 prompt "Intel MPX (Memory Protection Extensions)" 1750 def_bool n 1751 depends on CPU_SUP_INTEL 1752 ---help--- 1753 MPX provides hardware features that can be used in 1754 conjunction with compiler-instrumented code to check 1755 memory references. It is designed to detect buffer 1756 overflow or underflow bugs. 1757 1758 This option enables running applications which are 1759 instrumented or otherwise use MPX. It does not use MPX 1760 itself inside the kernel or to protect the kernel 1761 against bad memory references. 1762 1763 Enabling this option will make the kernel larger: 1764 ~8k of kernel text and 36 bytes of data on a 64-bit 1765 defconfig. It adds a long to the 'mm_struct' which 1766 will increase the kernel memory overhead of each 1767 process and adds some branches to paths used during 1768 exec() and munmap(). 1769 1770 For details, see Documentation/x86/intel_mpx.txt 1771 1772 If unsure, say N. 1773 1774config X86_INTEL_MEMORY_PROTECTION_KEYS 1775 prompt "Intel Memory Protection Keys" 1776 def_bool y 1777 # Note: only available in 64-bit mode 1778 depends on CPU_SUP_INTEL && X86_64 1779 select ARCH_USES_HIGH_VMA_FLAGS 1780 select ARCH_HAS_PKEYS 1781 ---help--- 1782 Memory Protection Keys provides a mechanism for enforcing 1783 page-based protections, but without requiring modification of the 1784 page tables when an application changes protection domains. 1785 1786 For details, see Documentation/x86/protection-keys.txt 1787 1788 If unsure, say y. 1789 1790config EFI 1791 bool "EFI runtime service support" 1792 depends on ACPI 1793 select UCS2_STRING 1794 select EFI_RUNTIME_WRAPPERS 1795 ---help--- 1796 This enables the kernel to use EFI runtime services that are 1797 available (such as the EFI variable services). 1798 1799 This option is only useful on systems that have EFI firmware. 1800 In addition, you should use the latest ELILO loader available 1801 at <http://elilo.sourceforge.net> in order to take advantage 1802 of EFI runtime services. However, even with this option, the 1803 resultant kernel should continue to boot on existing non-EFI 1804 platforms. 1805 1806config EFI_STUB 1807 bool "EFI stub support" 1808 depends on EFI && !X86_USE_3DNOW 1809 select RELOCATABLE 1810 ---help--- 1811 This kernel feature allows a bzImage to be loaded directly 1812 by EFI firmware without the use of a bootloader. 1813 1814 See Documentation/efi-stub.txt for more information. 1815 1816config EFI_MIXED 1817 bool "EFI mixed-mode support" 1818 depends on EFI_STUB && X86_64 1819 ---help--- 1820 Enabling this feature allows a 64-bit kernel to be booted 1821 on a 32-bit firmware, provided that your CPU supports 64-bit 1822 mode. 1823 1824 Note that it is not possible to boot a mixed-mode enabled 1825 kernel via the EFI boot stub - a bootloader that supports 1826 the EFI handover protocol must be used. 1827 1828 If unsure, say N. 1829 1830config SECCOMP 1831 def_bool y 1832 prompt "Enable seccomp to safely compute untrusted bytecode" 1833 ---help--- 1834 This kernel feature is useful for number crunching applications 1835 that may need to compute untrusted bytecode during their 1836 execution. By using pipes or other transports made available to 1837 the process as file descriptors supporting the read/write 1838 syscalls, it's possible to isolate those applications in 1839 their own address space using seccomp. Once seccomp is 1840 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1841 and the task is only allowed to execute a few safe syscalls 1842 defined by each seccomp mode. 1843 1844 If unsure, say Y. Only embedded should say N here. 1845 1846source kernel/Kconfig.hz 1847 1848config KEXEC 1849 bool "kexec system call" 1850 select KEXEC_CORE 1851 ---help--- 1852 kexec is a system call that implements the ability to shutdown your 1853 current kernel, and to start another kernel. It is like a reboot 1854 but it is independent of the system firmware. And like a reboot 1855 you can start any kernel with it, not just Linux. 1856 1857 The name comes from the similarity to the exec system call. 1858 1859 It is an ongoing process to be certain the hardware in a machine 1860 is properly shutdown, so do not be surprised if this code does not 1861 initially work for you. As of this writing the exact hardware 1862 interface is strongly in flux, so no good recommendation can be 1863 made. 1864 1865config KEXEC_FILE 1866 bool "kexec file based system call" 1867 select KEXEC_CORE 1868 select BUILD_BIN2C 1869 depends on X86_64 1870 depends on CRYPTO=y 1871 depends on CRYPTO_SHA256=y 1872 ---help--- 1873 This is new version of kexec system call. This system call is 1874 file based and takes file descriptors as system call argument 1875 for kernel and initramfs as opposed to list of segments as 1876 accepted by previous system call. 1877 1878config KEXEC_VERIFY_SIG 1879 bool "Verify kernel signature during kexec_file_load() syscall" 1880 depends on KEXEC_FILE 1881 ---help--- 1882 This option makes kernel signature verification mandatory for 1883 the kexec_file_load() syscall. 1884 1885 In addition to that option, you need to enable signature 1886 verification for the corresponding kernel image type being 1887 loaded in order for this to work. 1888 1889config KEXEC_BZIMAGE_VERIFY_SIG 1890 bool "Enable bzImage signature verification support" 1891 depends on KEXEC_VERIFY_SIG 1892 depends on SIGNED_PE_FILE_VERIFICATION 1893 select SYSTEM_TRUSTED_KEYRING 1894 ---help--- 1895 Enable bzImage signature verification support. 1896 1897config CRASH_DUMP 1898 bool "kernel crash dumps" 1899 depends on X86_64 || (X86_32 && HIGHMEM) 1900 ---help--- 1901 Generate crash dump after being started by kexec. 1902 This should be normally only set in special crash dump kernels 1903 which are loaded in the main kernel with kexec-tools into 1904 a specially reserved region and then later executed after 1905 a crash by kdump/kexec. The crash dump kernel must be compiled 1906 to a memory address not used by the main kernel or BIOS using 1907 PHYSICAL_START, or it must be built as a relocatable image 1908 (CONFIG_RELOCATABLE=y). 1909 For more details see Documentation/kdump/kdump.txt 1910 1911config KEXEC_JUMP 1912 bool "kexec jump" 1913 depends on KEXEC && HIBERNATION 1914 ---help--- 1915 Jump between original kernel and kexeced kernel and invoke 1916 code in physical address mode via KEXEC 1917 1918config PHYSICAL_START 1919 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1920 default "0x1000000" 1921 ---help--- 1922 This gives the physical address where the kernel is loaded. 1923 1924 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1925 bzImage will decompress itself to above physical address and 1926 run from there. Otherwise, bzImage will run from the address where 1927 it has been loaded by the boot loader and will ignore above physical 1928 address. 1929 1930 In normal kdump cases one does not have to set/change this option 1931 as now bzImage can be compiled as a completely relocatable image 1932 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1933 address. This option is mainly useful for the folks who don't want 1934 to use a bzImage for capturing the crash dump and want to use a 1935 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1936 to be specifically compiled to run from a specific memory area 1937 (normally a reserved region) and this option comes handy. 1938 1939 So if you are using bzImage for capturing the crash dump, 1940 leave the value here unchanged to 0x1000000 and set 1941 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1942 for capturing the crash dump change this value to start of 1943 the reserved region. In other words, it can be set based on 1944 the "X" value as specified in the "crashkernel=YM@XM" 1945 command line boot parameter passed to the panic-ed 1946 kernel. Please take a look at Documentation/kdump/kdump.txt 1947 for more details about crash dumps. 1948 1949 Usage of bzImage for capturing the crash dump is recommended as 1950 one does not have to build two kernels. Same kernel can be used 1951 as production kernel and capture kernel. Above option should have 1952 gone away after relocatable bzImage support is introduced. But it 1953 is present because there are users out there who continue to use 1954 vmlinux for dump capture. This option should go away down the 1955 line. 1956 1957 Don't change this unless you know what you are doing. 1958 1959config RELOCATABLE 1960 bool "Build a relocatable kernel" 1961 default y 1962 ---help--- 1963 This builds a kernel image that retains relocation information 1964 so it can be loaded someplace besides the default 1MB. 1965 The relocations tend to make the kernel binary about 10% larger, 1966 but are discarded at runtime. 1967 1968 One use is for the kexec on panic case where the recovery kernel 1969 must live at a different physical address than the primary 1970 kernel. 1971 1972 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1973 it has been loaded at and the compile time physical address 1974 (CONFIG_PHYSICAL_START) is used as the minimum location. 1975 1976config RANDOMIZE_BASE 1977 bool "Randomize the address of the kernel image (KASLR)" 1978 depends on RELOCATABLE 1979 default y 1980 ---help--- 1981 In support of Kernel Address Space Layout Randomization (KASLR), 1982 this randomizes the physical address at which the kernel image 1983 is decompressed and the virtual address where the kernel 1984 image is mapped, as a security feature that deters exploit 1985 attempts relying on knowledge of the location of kernel 1986 code internals. 1987 1988 On 64-bit, the kernel physical and virtual addresses are 1989 randomized separately. The physical address will be anywhere 1990 between 16MB and the top of physical memory (up to 64TB). The 1991 virtual address will be randomized from 16MB up to 1GB (9 bits 1992 of entropy). Note that this also reduces the memory space 1993 available to kernel modules from 1.5GB to 1GB. 1994 1995 On 32-bit, the kernel physical and virtual addresses are 1996 randomized together. They will be randomized from 16MB up to 1997 512MB (8 bits of entropy). 1998 1999 Entropy is generated using the RDRAND instruction if it is 2000 supported. If RDTSC is supported, its value is mixed into 2001 the entropy pool as well. If neither RDRAND nor RDTSC are 2002 supported, then entropy is read from the i8254 timer. The 2003 usable entropy is limited by the kernel being built using 2004 2GB addressing, and that PHYSICAL_ALIGN must be at a 2005 minimum of 2MB. As a result, only 10 bits of entropy are 2006 theoretically possible, but the implementations are further 2007 limited due to memory layouts. 2008 2009 If unsure, say Y. 2010 2011# Relocation on x86 needs some additional build support 2012config X86_NEED_RELOCS 2013 def_bool y 2014 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2015 2016config PHYSICAL_ALIGN 2017 hex "Alignment value to which kernel should be aligned" 2018 default "0x200000" 2019 range 0x2000 0x1000000 if X86_32 2020 range 0x200000 0x1000000 if X86_64 2021 ---help--- 2022 This value puts the alignment restrictions on physical address 2023 where kernel is loaded and run from. Kernel is compiled for an 2024 address which meets above alignment restriction. 2025 2026 If bootloader loads the kernel at a non-aligned address and 2027 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2028 address aligned to above value and run from there. 2029 2030 If bootloader loads the kernel at a non-aligned address and 2031 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2032 load address and decompress itself to the address it has been 2033 compiled for and run from there. The address for which kernel is 2034 compiled already meets above alignment restrictions. Hence the 2035 end result is that kernel runs from a physical address meeting 2036 above alignment restrictions. 2037 2038 On 32-bit this value must be a multiple of 0x2000. On 64-bit 2039 this value must be a multiple of 0x200000. 2040 2041 Don't change this unless you know what you are doing. 2042 2043config RANDOMIZE_MEMORY 2044 bool "Randomize the kernel memory sections" 2045 depends on X86_64 2046 depends on RANDOMIZE_BASE 2047 default RANDOMIZE_BASE 2048 ---help--- 2049 Randomizes the base virtual address of kernel memory sections 2050 (physical memory mapping, vmalloc & vmemmap). This security feature 2051 makes exploits relying on predictable memory locations less reliable. 2052 2053 The order of allocations remains unchanged. Entropy is generated in 2054 the same way as RANDOMIZE_BASE. Current implementation in the optimal 2055 configuration have in average 30,000 different possible virtual 2056 addresses for each memory section. 2057 2058 If unsure, say Y. 2059 2060config RANDOMIZE_MEMORY_PHYSICAL_PADDING 2061 hex "Physical memory mapping padding" if EXPERT 2062 depends on RANDOMIZE_MEMORY 2063 default "0xa" if MEMORY_HOTPLUG 2064 default "0x0" 2065 range 0x1 0x40 if MEMORY_HOTPLUG 2066 range 0x0 0x40 2067 ---help--- 2068 Define the padding in terabytes added to the existing physical 2069 memory size during kernel memory randomization. It is useful 2070 for memory hotplug support but reduces the entropy available for 2071 address randomization. 2072 2073 If unsure, leave at the default value. 2074 2075config HOTPLUG_CPU 2076 bool "Support for hot-pluggable CPUs" 2077 depends on SMP 2078 ---help--- 2079 Say Y here to allow turning CPUs off and on. CPUs can be 2080 controlled through /sys/devices/system/cpu. 2081 ( Note: power management support will enable this option 2082 automatically on SMP systems. ) 2083 Say N if you want to disable CPU hotplug. 2084 2085config BOOTPARAM_HOTPLUG_CPU0 2086 bool "Set default setting of cpu0_hotpluggable" 2087 default n 2088 depends on HOTPLUG_CPU 2089 ---help--- 2090 Set whether default state of cpu0_hotpluggable is on or off. 2091 2092 Say Y here to enable CPU0 hotplug by default. If this switch 2093 is turned on, there is no need to give cpu0_hotplug kernel 2094 parameter and the CPU0 hotplug feature is enabled by default. 2095 2096 Please note: there are two known CPU0 dependencies if you want 2097 to enable the CPU0 hotplug feature either by this switch or by 2098 cpu0_hotplug kernel parameter. 2099 2100 First, resume from hibernate or suspend always starts from CPU0. 2101 So hibernate and suspend are prevented if CPU0 is offline. 2102 2103 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2104 offline if any interrupt can not migrate out of CPU0. There may 2105 be other CPU0 dependencies. 2106 2107 Please make sure the dependencies are under your control before 2108 you enable this feature. 2109 2110 Say N if you don't want to enable CPU0 hotplug feature by default. 2111 You still can enable the CPU0 hotplug feature at boot by kernel 2112 parameter cpu0_hotplug. 2113 2114config DEBUG_HOTPLUG_CPU0 2115 def_bool n 2116 prompt "Debug CPU0 hotplug" 2117 depends on HOTPLUG_CPU 2118 ---help--- 2119 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2120 soon as possible and boots up userspace with CPU0 offlined. User 2121 can online CPU0 back after boot time. 2122 2123 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2124 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2125 compilation or giving cpu0_hotplug kernel parameter at boot. 2126 2127 If unsure, say N. 2128 2129config COMPAT_VDSO 2130 def_bool n 2131 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2132 depends on COMPAT_32 2133 ---help--- 2134 Certain buggy versions of glibc will crash if they are 2135 presented with a 32-bit vDSO that is not mapped at the address 2136 indicated in its segment table. 2137 2138 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2139 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2140 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2141 the only released version with the bug, but OpenSUSE 9 2142 contains a buggy "glibc 2.3.2". 2143 2144 The symptom of the bug is that everything crashes on startup, saying: 2145 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2146 2147 Saying Y here changes the default value of the vdso32 boot 2148 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2149 This works around the glibc bug but hurts performance. 2150 2151 If unsure, say N: if you are compiling your own kernel, you 2152 are unlikely to be using a buggy version of glibc. 2153 2154choice 2155 prompt "vsyscall table for legacy applications" 2156 depends on X86_64 2157 default LEGACY_VSYSCALL_EMULATE 2158 help 2159 Legacy user code that does not know how to find the vDSO expects 2160 to be able to issue three syscalls by calling fixed addresses in 2161 kernel space. Since this location is not randomized with ASLR, 2162 it can be used to assist security vulnerability exploitation. 2163 2164 This setting can be changed at boot time via the kernel command 2165 line parameter vsyscall=[native|emulate|none]. 2166 2167 On a system with recent enough glibc (2.14 or newer) and no 2168 static binaries, you can say None without a performance penalty 2169 to improve security. 2170 2171 If unsure, select "Emulate". 2172 2173 config LEGACY_VSYSCALL_NATIVE 2174 bool "Native" 2175 help 2176 Actual executable code is located in the fixed vsyscall 2177 address mapping, implementing time() efficiently. Since 2178 this makes the mapping executable, it can be used during 2179 security vulnerability exploitation (traditionally as 2180 ROP gadgets). This configuration is not recommended. 2181 2182 config LEGACY_VSYSCALL_EMULATE 2183 bool "Emulate" 2184 help 2185 The kernel traps and emulates calls into the fixed 2186 vsyscall address mapping. This makes the mapping 2187 non-executable, but it still contains known contents, 2188 which could be used in certain rare security vulnerability 2189 exploits. This configuration is recommended when userspace 2190 still uses the vsyscall area. 2191 2192 config LEGACY_VSYSCALL_NONE 2193 bool "None" 2194 help 2195 There will be no vsyscall mapping at all. This will 2196 eliminate any risk of ASLR bypass due to the vsyscall 2197 fixed address mapping. Attempts to use the vsyscalls 2198 will be reported to dmesg, so that either old or 2199 malicious userspace programs can be identified. 2200 2201endchoice 2202 2203config CMDLINE_BOOL 2204 bool "Built-in kernel command line" 2205 ---help--- 2206 Allow for specifying boot arguments to the kernel at 2207 build time. On some systems (e.g. embedded ones), it is 2208 necessary or convenient to provide some or all of the 2209 kernel boot arguments with the kernel itself (that is, 2210 to not rely on the boot loader to provide them.) 2211 2212 To compile command line arguments into the kernel, 2213 set this option to 'Y', then fill in the 2214 boot arguments in CONFIG_CMDLINE. 2215 2216 Systems with fully functional boot loaders (i.e. non-embedded) 2217 should leave this option set to 'N'. 2218 2219config CMDLINE 2220 string "Built-in kernel command string" 2221 depends on CMDLINE_BOOL 2222 default "" 2223 ---help--- 2224 Enter arguments here that should be compiled into the kernel 2225 image and used at boot time. If the boot loader provides a 2226 command line at boot time, it is appended to this string to 2227 form the full kernel command line, when the system boots. 2228 2229 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2230 change this behavior. 2231 2232 In most cases, the command line (whether built-in or provided 2233 by the boot loader) should specify the device for the root 2234 file system. 2235 2236config CMDLINE_OVERRIDE 2237 bool "Built-in command line overrides boot loader arguments" 2238 depends on CMDLINE_BOOL 2239 ---help--- 2240 Set this option to 'Y' to have the kernel ignore the boot loader 2241 command line, and use ONLY the built-in command line. 2242 2243 This is used to work around broken boot loaders. This should 2244 be set to 'N' under normal conditions. 2245 2246config MODIFY_LDT_SYSCALL 2247 bool "Enable the LDT (local descriptor table)" if EXPERT 2248 default y 2249 ---help--- 2250 Linux can allow user programs to install a per-process x86 2251 Local Descriptor Table (LDT) using the modify_ldt(2) system 2252 call. This is required to run 16-bit or segmented code such as 2253 DOSEMU or some Wine programs. It is also used by some very old 2254 threading libraries. 2255 2256 Enabling this feature adds a small amount of overhead to 2257 context switches and increases the low-level kernel attack 2258 surface. Disabling it removes the modify_ldt(2) system call. 2259 2260 Saying 'N' here may make sense for embedded or server kernels. 2261 2262source "kernel/livepatch/Kconfig" 2263 2264endmenu 2265 2266config ARCH_ENABLE_MEMORY_HOTPLUG 2267 def_bool y 2268 depends on X86_64 || (X86_32 && HIGHMEM) 2269 2270config ARCH_ENABLE_MEMORY_HOTREMOVE 2271 def_bool y 2272 depends on MEMORY_HOTPLUG 2273 2274config USE_PERCPU_NUMA_NODE_ID 2275 def_bool y 2276 depends on NUMA 2277 2278config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2279 def_bool y 2280 depends on X86_64 || X86_PAE 2281 2282config ARCH_ENABLE_HUGEPAGE_MIGRATION 2283 def_bool y 2284 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2285 2286menu "Power management and ACPI options" 2287 2288config ARCH_HIBERNATION_HEADER 2289 def_bool y 2290 depends on X86_64 && HIBERNATION 2291 2292source "kernel/power/Kconfig" 2293 2294source "drivers/acpi/Kconfig" 2295 2296source "drivers/sfi/Kconfig" 2297 2298config X86_APM_BOOT 2299 def_bool y 2300 depends on APM 2301 2302menuconfig APM 2303 tristate "APM (Advanced Power Management) BIOS support" 2304 depends on X86_32 && PM_SLEEP 2305 ---help--- 2306 APM is a BIOS specification for saving power using several different 2307 techniques. This is mostly useful for battery powered laptops with 2308 APM compliant BIOSes. If you say Y here, the system time will be 2309 reset after a RESUME operation, the /proc/apm device will provide 2310 battery status information, and user-space programs will receive 2311 notification of APM "events" (e.g. battery status change). 2312 2313 If you select "Y" here, you can disable actual use of the APM 2314 BIOS by passing the "apm=off" option to the kernel at boot time. 2315 2316 Note that the APM support is almost completely disabled for 2317 machines with more than one CPU. 2318 2319 In order to use APM, you will need supporting software. For location 2320 and more information, read <file:Documentation/power/apm-acpi.txt> 2321 and the Battery Powered Linux mini-HOWTO, available from 2322 <http://www.tldp.org/docs.html#howto>. 2323 2324 This driver does not spin down disk drives (see the hdparm(8) 2325 manpage ("man 8 hdparm") for that), and it doesn't turn off 2326 VESA-compliant "green" monitors. 2327 2328 This driver does not support the TI 4000M TravelMate and the ACER 2329 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2330 desktop machines also don't have compliant BIOSes, and this driver 2331 may cause those machines to panic during the boot phase. 2332 2333 Generally, if you don't have a battery in your machine, there isn't 2334 much point in using this driver and you should say N. If you get 2335 random kernel OOPSes or reboots that don't seem to be related to 2336 anything, try disabling/enabling this option (or disabling/enabling 2337 APM in your BIOS). 2338 2339 Some other things you should try when experiencing seemingly random, 2340 "weird" problems: 2341 2342 1) make sure that you have enough swap space and that it is 2343 enabled. 2344 2) pass the "no-hlt" option to the kernel 2345 3) switch on floating point emulation in the kernel and pass 2346 the "no387" option to the kernel 2347 4) pass the "floppy=nodma" option to the kernel 2348 5) pass the "mem=4M" option to the kernel (thereby disabling 2349 all but the first 4 MB of RAM) 2350 6) make sure that the CPU is not over clocked. 2351 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2352 8) disable the cache from your BIOS settings 2353 9) install a fan for the video card or exchange video RAM 2354 10) install a better fan for the CPU 2355 11) exchange RAM chips 2356 12) exchange the motherboard. 2357 2358 To compile this driver as a module, choose M here: the 2359 module will be called apm. 2360 2361if APM 2362 2363config APM_IGNORE_USER_SUSPEND 2364 bool "Ignore USER SUSPEND" 2365 ---help--- 2366 This option will ignore USER SUSPEND requests. On machines with a 2367 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2368 series notebooks, it is necessary to say Y because of a BIOS bug. 2369 2370config APM_DO_ENABLE 2371 bool "Enable PM at boot time" 2372 ---help--- 2373 Enable APM features at boot time. From page 36 of the APM BIOS 2374 specification: "When disabled, the APM BIOS does not automatically 2375 power manage devices, enter the Standby State, enter the Suspend 2376 State, or take power saving steps in response to CPU Idle calls." 2377 This driver will make CPU Idle calls when Linux is idle (unless this 2378 feature is turned off -- see "Do CPU IDLE calls", below). This 2379 should always save battery power, but more complicated APM features 2380 will be dependent on your BIOS implementation. You may need to turn 2381 this option off if your computer hangs at boot time when using APM 2382 support, or if it beeps continuously instead of suspending. Turn 2383 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2384 T400CDT. This is off by default since most machines do fine without 2385 this feature. 2386 2387config APM_CPU_IDLE 2388 depends on CPU_IDLE 2389 bool "Make CPU Idle calls when idle" 2390 ---help--- 2391 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2392 On some machines, this can activate improved power savings, such as 2393 a slowed CPU clock rate, when the machine is idle. These idle calls 2394 are made after the idle loop has run for some length of time (e.g., 2395 333 mS). On some machines, this will cause a hang at boot time or 2396 whenever the CPU becomes idle. (On machines with more than one CPU, 2397 this option does nothing.) 2398 2399config APM_DISPLAY_BLANK 2400 bool "Enable console blanking using APM" 2401 ---help--- 2402 Enable console blanking using the APM. Some laptops can use this to 2403 turn off the LCD backlight when the screen blanker of the Linux 2404 virtual console blanks the screen. Note that this is only used by 2405 the virtual console screen blanker, and won't turn off the backlight 2406 when using the X Window system. This also doesn't have anything to 2407 do with your VESA-compliant power-saving monitor. Further, this 2408 option doesn't work for all laptops -- it might not turn off your 2409 backlight at all, or it might print a lot of errors to the console, 2410 especially if you are using gpm. 2411 2412config APM_ALLOW_INTS 2413 bool "Allow interrupts during APM BIOS calls" 2414 ---help--- 2415 Normally we disable external interrupts while we are making calls to 2416 the APM BIOS as a measure to lessen the effects of a badly behaving 2417 BIOS implementation. The BIOS should reenable interrupts if it 2418 needs to. Unfortunately, some BIOSes do not -- especially those in 2419 many of the newer IBM Thinkpads. If you experience hangs when you 2420 suspend, try setting this to Y. Otherwise, say N. 2421 2422endif # APM 2423 2424source "drivers/cpufreq/Kconfig" 2425 2426source "drivers/cpuidle/Kconfig" 2427 2428source "drivers/idle/Kconfig" 2429 2430endmenu 2431 2432 2433menu "Bus options (PCI etc.)" 2434 2435config PCI 2436 bool "PCI support" 2437 default y 2438 ---help--- 2439 Find out whether you have a PCI motherboard. PCI is the name of a 2440 bus system, i.e. the way the CPU talks to the other stuff inside 2441 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2442 VESA. If you have PCI, say Y, otherwise N. 2443 2444choice 2445 prompt "PCI access mode" 2446 depends on X86_32 && PCI 2447 default PCI_GOANY 2448 ---help--- 2449 On PCI systems, the BIOS can be used to detect the PCI devices and 2450 determine their configuration. However, some old PCI motherboards 2451 have BIOS bugs and may crash if this is done. Also, some embedded 2452 PCI-based systems don't have any BIOS at all. Linux can also try to 2453 detect the PCI hardware directly without using the BIOS. 2454 2455 With this option, you can specify how Linux should detect the 2456 PCI devices. If you choose "BIOS", the BIOS will be used, 2457 if you choose "Direct", the BIOS won't be used, and if you 2458 choose "MMConfig", then PCI Express MMCONFIG will be used. 2459 If you choose "Any", the kernel will try MMCONFIG, then the 2460 direct access method and falls back to the BIOS if that doesn't 2461 work. If unsure, go with the default, which is "Any". 2462 2463config PCI_GOBIOS 2464 bool "BIOS" 2465 2466config PCI_GOMMCONFIG 2467 bool "MMConfig" 2468 2469config PCI_GODIRECT 2470 bool "Direct" 2471 2472config PCI_GOOLPC 2473 bool "OLPC XO-1" 2474 depends on OLPC 2475 2476config PCI_GOANY 2477 bool "Any" 2478 2479endchoice 2480 2481config PCI_BIOS 2482 def_bool y 2483 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2484 2485# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2486config PCI_DIRECT 2487 def_bool y 2488 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2489 2490config PCI_MMCONFIG 2491 def_bool y 2492 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2493 2494config PCI_OLPC 2495 def_bool y 2496 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2497 2498config PCI_XEN 2499 def_bool y 2500 depends on PCI && XEN 2501 select SWIOTLB_XEN 2502 2503config PCI_DOMAINS 2504 def_bool y 2505 depends on PCI 2506 2507config PCI_MMCONFIG 2508 bool "Support mmconfig PCI config space access" 2509 depends on X86_64 && PCI && ACPI 2510 2511config PCI_CNB20LE_QUIRK 2512 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2513 depends on PCI 2514 help 2515 Read the PCI windows out of the CNB20LE host bridge. This allows 2516 PCI hotplug to work on systems with the CNB20LE chipset which do 2517 not have ACPI. 2518 2519 There's no public spec for this chipset, and this functionality 2520 is known to be incomplete. 2521 2522 You should say N unless you know you need this. 2523 2524source "drivers/pci/Kconfig" 2525 2526config ISA_BUS 2527 bool "ISA-style bus support on modern systems" if EXPERT 2528 select ISA_BUS_API 2529 help 2530 Enables ISA-style drivers on modern systems. This is necessary to 2531 support PC/104 devices on X86_64 platforms. 2532 2533 If unsure, say N. 2534 2535# x86_64 have no ISA slots, but can have ISA-style DMA. 2536config ISA_DMA_API 2537 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2538 default y 2539 help 2540 Enables ISA-style DMA support for devices requiring such controllers. 2541 If unsure, say Y. 2542 2543if X86_32 2544 2545config ISA 2546 bool "ISA support" 2547 ---help--- 2548 Find out whether you have ISA slots on your motherboard. ISA is the 2549 name of a bus system, i.e. the way the CPU talks to the other stuff 2550 inside your box. Other bus systems are PCI, EISA, MicroChannel 2551 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2552 newer boards don't support it. If you have ISA, say Y, otherwise N. 2553 2554config EISA 2555 bool "EISA support" 2556 depends on ISA 2557 ---help--- 2558 The Extended Industry Standard Architecture (EISA) bus was 2559 developed as an open alternative to the IBM MicroChannel bus. 2560 2561 The EISA bus provided some of the features of the IBM MicroChannel 2562 bus while maintaining backward compatibility with cards made for 2563 the older ISA bus. The EISA bus saw limited use between 1988 and 2564 1995 when it was made obsolete by the PCI bus. 2565 2566 Say Y here if you are building a kernel for an EISA-based machine. 2567 2568 Otherwise, say N. 2569 2570source "drivers/eisa/Kconfig" 2571 2572config SCx200 2573 tristate "NatSemi SCx200 support" 2574 ---help--- 2575 This provides basic support for National Semiconductor's 2576 (now AMD's) Geode processors. The driver probes for the 2577 PCI-IDs of several on-chip devices, so its a good dependency 2578 for other scx200_* drivers. 2579 2580 If compiled as a module, the driver is named scx200. 2581 2582config SCx200HR_TIMER 2583 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2584 depends on SCx200 2585 default y 2586 ---help--- 2587 This driver provides a clocksource built upon the on-chip 2588 27MHz high-resolution timer. Its also a workaround for 2589 NSC Geode SC-1100's buggy TSC, which loses time when the 2590 processor goes idle (as is done by the scheduler). The 2591 other workaround is idle=poll boot option. 2592 2593config OLPC 2594 bool "One Laptop Per Child support" 2595 depends on !X86_PAE 2596 select GPIOLIB 2597 select OF 2598 select OF_PROMTREE 2599 select IRQ_DOMAIN 2600 ---help--- 2601 Add support for detecting the unique features of the OLPC 2602 XO hardware. 2603 2604config OLPC_XO1_PM 2605 bool "OLPC XO-1 Power Management" 2606 depends on OLPC && MFD_CS5535 && PM_SLEEP 2607 select MFD_CORE 2608 ---help--- 2609 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2610 2611config OLPC_XO1_RTC 2612 bool "OLPC XO-1 Real Time Clock" 2613 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2614 ---help--- 2615 Add support for the XO-1 real time clock, which can be used as a 2616 programmable wakeup source. 2617 2618config OLPC_XO1_SCI 2619 bool "OLPC XO-1 SCI extras" 2620 depends on OLPC && OLPC_XO1_PM 2621 depends on INPUT=y 2622 select POWER_SUPPLY 2623 select GPIO_CS5535 2624 select MFD_CORE 2625 ---help--- 2626 Add support for SCI-based features of the OLPC XO-1 laptop: 2627 - EC-driven system wakeups 2628 - Power button 2629 - Ebook switch 2630 - Lid switch 2631 - AC adapter status updates 2632 - Battery status updates 2633 2634config OLPC_XO15_SCI 2635 bool "OLPC XO-1.5 SCI extras" 2636 depends on OLPC && ACPI 2637 select POWER_SUPPLY 2638 ---help--- 2639 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2640 - EC-driven system wakeups 2641 - AC adapter status updates 2642 - Battery status updates 2643 2644config ALIX 2645 bool "PCEngines ALIX System Support (LED setup)" 2646 select GPIOLIB 2647 ---help--- 2648 This option enables system support for the PCEngines ALIX. 2649 At present this just sets up LEDs for GPIO control on 2650 ALIX2/3/6 boards. However, other system specific setup should 2651 get added here. 2652 2653 Note: You must still enable the drivers for GPIO and LED support 2654 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2655 2656 Note: You have to set alix.force=1 for boards with Award BIOS. 2657 2658config NET5501 2659 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2660 select GPIOLIB 2661 ---help--- 2662 This option enables system support for the Soekris Engineering net5501. 2663 2664config GEOS 2665 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2666 select GPIOLIB 2667 depends on DMI 2668 ---help--- 2669 This option enables system support for the Traverse Technologies GEOS. 2670 2671config TS5500 2672 bool "Technologic Systems TS-5500 platform support" 2673 depends on MELAN 2674 select CHECK_SIGNATURE 2675 select NEW_LEDS 2676 select LEDS_CLASS 2677 ---help--- 2678 This option enables system support for the Technologic Systems TS-5500. 2679 2680endif # X86_32 2681 2682config AMD_NB 2683 def_bool y 2684 depends on CPU_SUP_AMD && PCI 2685 2686source "drivers/pcmcia/Kconfig" 2687 2688config RAPIDIO 2689 tristate "RapidIO support" 2690 depends on PCI 2691 default n 2692 help 2693 If enabled this option will include drivers and the core 2694 infrastructure code to support RapidIO interconnect devices. 2695 2696source "drivers/rapidio/Kconfig" 2697 2698config X86_SYSFB 2699 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2700 help 2701 Firmwares often provide initial graphics framebuffers so the BIOS, 2702 bootloader or kernel can show basic video-output during boot for 2703 user-guidance and debugging. Historically, x86 used the VESA BIOS 2704 Extensions and EFI-framebuffers for this, which are mostly limited 2705 to x86. 2706 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2707 framebuffers so the new generic system-framebuffer drivers can be 2708 used on x86. If the framebuffer is not compatible with the generic 2709 modes, it is adverticed as fallback platform framebuffer so legacy 2710 drivers like efifb, vesafb and uvesafb can pick it up. 2711 If this option is not selected, all system framebuffers are always 2712 marked as fallback platform framebuffers as usual. 2713 2714 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2715 not be able to pick up generic system framebuffers if this option 2716 is selected. You are highly encouraged to enable simplefb as 2717 replacement if you select this option. simplefb can correctly deal 2718 with generic system framebuffers. But you should still keep vesafb 2719 and others enabled as fallback if a system framebuffer is 2720 incompatible with simplefb. 2721 2722 If unsure, say Y. 2723 2724endmenu 2725 2726 2727menu "Executable file formats / Emulations" 2728 2729source "fs/Kconfig.binfmt" 2730 2731config IA32_EMULATION 2732 bool "IA32 Emulation" 2733 depends on X86_64 2734 select ARCH_WANT_OLD_COMPAT_IPC 2735 select BINFMT_ELF 2736 select COMPAT_BINFMT_ELF 2737 select COMPAT_OLD_SIGACTION 2738 ---help--- 2739 Include code to run legacy 32-bit programs under a 2740 64-bit kernel. You should likely turn this on, unless you're 2741 100% sure that you don't have any 32-bit programs left. 2742 2743config IA32_AOUT 2744 tristate "IA32 a.out support" 2745 depends on IA32_EMULATION 2746 ---help--- 2747 Support old a.out binaries in the 32bit emulation. 2748 2749config X86_X32 2750 bool "x32 ABI for 64-bit mode" 2751 depends on X86_64 2752 ---help--- 2753 Include code to run binaries for the x32 native 32-bit ABI 2754 for 64-bit processors. An x32 process gets access to the 2755 full 64-bit register file and wide data path while leaving 2756 pointers at 32 bits for smaller memory footprint. 2757 2758 You will need a recent binutils (2.22 or later) with 2759 elf32_x86_64 support enabled to compile a kernel with this 2760 option set. 2761 2762config COMPAT_32 2763 def_bool y 2764 depends on IA32_EMULATION || X86_32 2765 select HAVE_UID16 2766 select OLD_SIGSUSPEND3 2767 2768config COMPAT 2769 def_bool y 2770 depends on IA32_EMULATION || X86_X32 2771 2772if COMPAT 2773config COMPAT_FOR_U64_ALIGNMENT 2774 def_bool y 2775 2776config SYSVIPC_COMPAT 2777 def_bool y 2778 depends on SYSVIPC 2779 2780config KEYS_COMPAT 2781 def_bool y 2782 depends on KEYS 2783endif 2784 2785endmenu 2786 2787 2788config HAVE_ATOMIC_IOMAP 2789 def_bool y 2790 depends on X86_32 2791 2792config X86_DEV_DMA_OPS 2793 bool 2794 depends on X86_64 || STA2X11 2795 2796config X86_DMA_REMAP 2797 bool 2798 depends on STA2X11 2799 2800source "net/Kconfig" 2801 2802source "drivers/Kconfig" 2803 2804source "drivers/firmware/Kconfig" 2805 2806source "fs/Kconfig" 2807 2808source "arch/x86/Kconfig.debug" 2809 2810source "security/Kconfig" 2811 2812source "crypto/Kconfig" 2813 2814source "arch/x86/kvm/Kconfig" 2815 2816source "lib/Kconfig" 2817