1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH != "i386" 5 ---help--- 6 Say yes to build a 64-bit kernel - formerly known as x86_64 7 Say no to build a 32-bit kernel - formerly known as i386 8 9config X86_32 10 def_bool y 11 depends on !64BIT 12 13config X86_64 14 def_bool y 15 depends on 64BIT 16 17### Arch settings 18config X86 19 def_bool y 20 select ACPI_LEGACY_TABLES_LOOKUP if ACPI 21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 22 select ANON_INODES 23 select ARCH_CLOCKSOURCE_DATA 24 select ARCH_DISCARD_MEMBLOCK 25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 27 select ARCH_HAS_ELF_RANDOMIZE 28 select ARCH_HAS_FAST_MULTIPLIER 29 select ARCH_HAS_GCOV_PROFILE_ALL 30 select ARCH_HAS_KCOV if X86_64 31 select ARCH_HAS_PMEM_API if X86_64 32 select ARCH_HAS_MMIO_FLUSH 33 select ARCH_HAS_SG_CHAIN 34 select ARCH_HAVE_NMI_SAFE_CMPXCHG 35 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 36 select ARCH_MIGHT_HAVE_PC_PARPORT 37 select ARCH_MIGHT_HAVE_PC_SERIO 38 select ARCH_SUPPORTS_ATOMIC_RMW 39 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 40 select ARCH_SUPPORTS_INT128 if X86_64 41 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 42 select ARCH_USE_BUILTIN_BSWAP 43 select ARCH_USE_CMPXCHG_LOCKREF if X86_64 44 select ARCH_USE_QUEUED_RWLOCKS 45 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 46 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 47 select ARCH_WANT_FRAME_POINTERS 48 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 49 select HAVE_ARCH_MMAP_RND_BITS if MMU 50 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 51 select ARCH_WANT_OPTIONAL_GPIOLIB 52 select BUILDTIME_EXTABLE_SORT 53 select CLKEVT_I8253 54 select CLKSRC_I8253 if X86_32 55 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 56 select CLOCKSOURCE_WATCHDOG 57 select CLONE_BACKWARDS if X86_32 58 select COMPAT_OLD_SIGACTION if IA32_EMULATION 59 select DCACHE_WORD_ACCESS 60 select EDAC_ATOMIC_SCRUB 61 select EDAC_SUPPORT 62 select GENERIC_CLOCKEVENTS 63 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 64 select GENERIC_CLOCKEVENTS_MIN_ADJUST 65 select GENERIC_CMOS_UPDATE 66 select GENERIC_CPU_AUTOPROBE 67 select GENERIC_CPU_VULNERABILITIES 68 select GENERIC_EARLY_IOREMAP 69 select GENERIC_FIND_FIRST_BIT 70 select GENERIC_IOMAP 71 select GENERIC_IRQ_PROBE 72 select GENERIC_IRQ_SHOW 73 select GENERIC_PENDING_IRQ if SMP 74 select GENERIC_SMP_IDLE_THREAD 75 select GENERIC_STRNCPY_FROM_USER 76 select GENERIC_STRNLEN_USER 77 select GENERIC_TIME_VSYSCALL 78 select HAVE_ACPI_APEI if ACPI 79 select HAVE_ACPI_APEI_NMI if ACPI 80 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 81 select HAVE_AOUT if X86_32 82 select HAVE_ARCH_AUDITSYSCALL 83 select HAVE_ARCH_HARDENED_USERCOPY 84 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 85 select HAVE_ARCH_JUMP_LABEL 86 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 87 select HAVE_ARCH_KGDB 88 select HAVE_ARCH_KMEMCHECK 89 select HAVE_ARCH_SECCOMP_FILTER 90 select HAVE_ARCH_SOFT_DIRTY if X86_64 91 select HAVE_ARCH_TRACEHOOK 92 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 93 select HAVE_ARCH_WITHIN_STACK_FRAMES 94 select HAVE_BPF_JIT if X86_64 95 select HAVE_EBPF_JIT if X86_64 96 select HAVE_CC_STACKPROTECTOR 97 select HAVE_CMPXCHG_DOUBLE 98 select HAVE_CMPXCHG_LOCAL 99 select HAVE_CONTEXT_TRACKING if X86_64 100 select HAVE_COPY_THREAD_TLS 101 select HAVE_C_RECORDMCOUNT 102 select HAVE_DEBUG_KMEMLEAK 103 select HAVE_DEBUG_STACKOVERFLOW 104 select HAVE_DMA_API_DEBUG 105 select HAVE_DMA_ATTRS 106 select HAVE_DMA_CONTIGUOUS 107 select HAVE_DYNAMIC_FTRACE 108 select HAVE_DYNAMIC_FTRACE_WITH_REGS 109 select HAVE_EFFICIENT_UNALIGNED_ACCESS 110 select HAVE_EXIT_THREAD 111 select HAVE_FENTRY if X86_64 112 select HAVE_FTRACE_MCOUNT_RECORD 113 select HAVE_FUNCTION_GRAPH_FP_TEST 114 select HAVE_FUNCTION_GRAPH_TRACER 115 select HAVE_FUNCTION_TRACER 116 select HAVE_GENERIC_DMA_COHERENT if X86_32 117 select HAVE_HW_BREAKPOINT 118 select HAVE_IDE 119 select HAVE_IOREMAP_PROT 120 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 121 select HAVE_IRQ_TIME_ACCOUNTING 122 select HAVE_KERNEL_BZIP2 123 select HAVE_KERNEL_GZIP 124 select HAVE_KERNEL_LZ4 125 select HAVE_KERNEL_LZMA 126 select HAVE_KERNEL_LZO 127 select HAVE_KERNEL_XZ 128 select HAVE_KPROBES 129 select HAVE_KPROBES_ON_FTRACE 130 select HAVE_KRETPROBES 131 select HAVE_KVM 132 select HAVE_LIVEPATCH if X86_64 133 select HAVE_MEMBLOCK 134 select HAVE_MEMBLOCK_NODE_MAP 135 select HAVE_MIXED_BREAKPOINTS_REGS 136 select HAVE_OPROFILE 137 select HAVE_OPTPROBES 138 select HAVE_PCSPKR_PLATFORM 139 select HAVE_PERF_EVENTS 140 select HAVE_PERF_EVENTS_NMI 141 select HAVE_PERF_REGS 142 select HAVE_PERF_USER_STACK_DUMP 143 select HAVE_REGS_AND_STACK_ACCESS_API 144 select HAVE_SYSCALL_TRACEPOINTS 145 select HAVE_UID16 if X86_32 || IA32_EMULATION 146 select HAVE_UNSTABLE_SCHED_CLOCK 147 select HAVE_USER_RETURN_NOTIFIER 148 select IRQ_FORCED_THREADING 149 select MODULES_USE_ELF_RELA if X86_64 150 select MODULES_USE_ELF_REL if X86_32 151 select OLD_SIGACTION if X86_32 152 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 153 select PERF_EVENTS 154 select RTC_LIB 155 select SPARSE_IRQ 156 select SRCU 157 select SYSCTL_EXCEPTION_TRACE 158 select USER_STACKTRACE_SUPPORT 159 select VIRT_TO_BUS 160 select X86_DEV_DMA_OPS if X86_64 161 select X86_FEATURE_NAMES if PROC_FS 162 163config INSTRUCTION_DECODER 164 def_bool y 165 depends on KPROBES || PERF_EVENTS || UPROBES 166 167config PERF_EVENTS_INTEL_UNCORE 168 def_bool y 169 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI 170 171config OUTPUT_FORMAT 172 string 173 default "elf32-i386" if X86_32 174 default "elf64-x86-64" if X86_64 175 176config ARCH_DEFCONFIG 177 string 178 default "arch/x86/configs/i386_defconfig" if X86_32 179 default "arch/x86/configs/x86_64_defconfig" if X86_64 180 181config LOCKDEP_SUPPORT 182 def_bool y 183 184config STACKTRACE_SUPPORT 185 def_bool y 186 187config HAVE_LATENCYTOP_SUPPORT 188 def_bool y 189 190config MMU 191 def_bool y 192 193config ARCH_MMAP_RND_BITS_MIN 194 default 28 if 64BIT 195 default 8 196 197config ARCH_MMAP_RND_BITS_MAX 198 default 32 if 64BIT 199 default 16 200 201config ARCH_MMAP_RND_COMPAT_BITS_MIN 202 default 8 203 204config ARCH_MMAP_RND_COMPAT_BITS_MAX 205 default 16 206 207config SBUS 208 bool 209 210config NEED_DMA_MAP_STATE 211 def_bool y 212 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 213 214config NEED_SG_DMA_LENGTH 215 def_bool y 216 217config GENERIC_ISA_DMA 218 def_bool y 219 depends on ISA_DMA_API 220 221config GENERIC_BUG 222 def_bool y 223 depends on BUG 224 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 225 226config GENERIC_BUG_RELATIVE_POINTERS 227 bool 228 229config GENERIC_HWEIGHT 230 def_bool y 231 232config ARCH_MAY_HAVE_PC_FDC 233 def_bool y 234 depends on ISA_DMA_API 235 236config RWSEM_XCHGADD_ALGORITHM 237 def_bool y 238 239config GENERIC_CALIBRATE_DELAY 240 def_bool y 241 242config ARCH_HAS_CPU_RELAX 243 def_bool y 244 245config ARCH_HAS_CACHE_LINE_SIZE 246 def_bool y 247 248config HAVE_SETUP_PER_CPU_AREA 249 def_bool y 250 251config NEED_PER_CPU_EMBED_FIRST_CHUNK 252 def_bool y 253 254config NEED_PER_CPU_PAGE_FIRST_CHUNK 255 def_bool y 256 257config ARCH_HIBERNATION_POSSIBLE 258 def_bool y 259 260config ARCH_SUSPEND_POSSIBLE 261 def_bool y 262 263config ARCH_WANT_HUGE_PMD_SHARE 264 def_bool y 265 266config ARCH_WANT_GENERAL_HUGETLB 267 def_bool y 268 269config ZONE_DMA32 270 def_bool y if X86_64 271 272config AUDIT_ARCH 273 def_bool y if X86_64 274 275config ARCH_SUPPORTS_OPTIMIZED_INLINING 276 def_bool y 277 278config ARCH_SUPPORTS_DEBUG_PAGEALLOC 279 def_bool y 280 281config KASAN_SHADOW_OFFSET 282 hex 283 depends on KASAN 284 default 0xdffffc0000000000 285 286config HAVE_INTEL_TXT 287 def_bool y 288 depends on INTEL_IOMMU && ACPI 289 290config X86_32_SMP 291 def_bool y 292 depends on X86_32 && SMP 293 294config X86_64_SMP 295 def_bool y 296 depends on X86_64 && SMP 297 298config X86_32_LAZY_GS 299 def_bool y 300 depends on X86_32 && !CC_STACKPROTECTOR 301 302config ARCH_SUPPORTS_UPROBES 303 def_bool y 304 305config FIX_EARLYCON_MEM 306 def_bool y 307 308config DEBUG_RODATA 309 def_bool y 310 311config PGTABLE_LEVELS 312 int 313 default 4 if X86_64 314 default 3 if X86_PAE 315 default 2 316 317source "init/Kconfig" 318source "kernel/Kconfig.freezer" 319 320menu "Processor type and features" 321 322config ZONE_DMA 323 bool "DMA memory allocation support" if EXPERT 324 default y 325 help 326 DMA memory allocation support allows devices with less than 32-bit 327 addressing to allocate within the first 16MB of address space. 328 Disable if no such devices will be used. 329 330 If unsure, say Y. 331 332config SMP 333 bool "Symmetric multi-processing support" 334 ---help--- 335 This enables support for systems with more than one CPU. If you have 336 a system with only one CPU, say N. If you have a system with more 337 than one CPU, say Y. 338 339 If you say N here, the kernel will run on uni- and multiprocessor 340 machines, but will use only one CPU of a multiprocessor machine. If 341 you say Y here, the kernel will run on many, but not all, 342 uniprocessor machines. On a uniprocessor machine, the kernel 343 will run faster if you say N here. 344 345 Note that if you say Y here and choose architecture "586" or 346 "Pentium" under "Processor family", the kernel will not work on 486 347 architectures. Similarly, multiprocessor kernels for the "PPro" 348 architecture may not work on all Pentium based boards. 349 350 People using multiprocessor machines who say Y here should also say 351 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 352 Management" code will be disabled if you say Y here. 353 354 See also <file:Documentation/x86/i386/IO-APIC.txt>, 355 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 356 <http://www.tldp.org/docs.html#howto>. 357 358 If you don't know what to do here, say N. 359 360config X86_FEATURE_NAMES 361 bool "Processor feature human-readable names" if EMBEDDED 362 default y 363 ---help--- 364 This option compiles in a table of x86 feature bits and corresponding 365 names. This is required to support /proc/cpuinfo and a few kernel 366 messages. You can disable this to save space, at the expense of 367 making those few kernel messages show numeric feature bits instead. 368 369 If in doubt, say Y. 370 371config X86_FAST_FEATURE_TESTS 372 bool "Fast CPU feature tests" if EMBEDDED 373 default y 374 ---help--- 375 Some fast-paths in the kernel depend on the capabilities of the CPU. 376 Say Y here for the kernel to patch in the appropriate code at runtime 377 based on the capabilities of the CPU. The infrastructure for patching 378 code at runtime takes up some additional space; space-constrained 379 embedded systems may wish to say N here to produce smaller, slightly 380 slower code. 381 382config X86_X2APIC 383 bool "Support x2apic" 384 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 385 ---help--- 386 This enables x2apic support on CPUs that have this feature. 387 388 This allows 32-bit apic IDs (so it can support very large systems), 389 and accesses the local apic via MSRs not via mmio. 390 391 If you don't know what to do here, say N. 392 393config X86_MPPARSE 394 bool "Enable MPS table" if ACPI || SFI 395 default y 396 depends on X86_LOCAL_APIC 397 ---help--- 398 For old smp systems that do not have proper acpi support. Newer systems 399 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 400 401config X86_BIGSMP 402 bool "Support for big SMP systems with more than 8 CPUs" 403 depends on X86_32 && SMP 404 ---help--- 405 This option is needed for the systems that have more than 8 CPUs 406 407config GOLDFISH 408 def_bool y 409 depends on X86_GOLDFISH 410 411config RETPOLINE 412 bool "Avoid speculative indirect branches in kernel" 413 default y 414 ---help--- 415 Compile kernel with the retpoline compiler options to guard against 416 kernel-to-user data leaks by avoiding speculative indirect 417 branches. Requires a compiler with -mindirect-branch=thunk-extern 418 support for full protection. The kernel may run slower. 419 420 Without compiler support, at least indirect branches in assembler 421 code are eliminated. Since this includes the syscall entry path, 422 it is not entirely pointless. 423 424if X86_32 425config X86_EXTENDED_PLATFORM 426 bool "Support for extended (non-PC) x86 platforms" 427 default y 428 ---help--- 429 If you disable this option then the kernel will only support 430 standard PC platforms. (which covers the vast majority of 431 systems out there.) 432 433 If you enable this option then you'll be able to select support 434 for the following (non-PC) 32 bit x86 platforms: 435 Goldfish (Android emulator) 436 AMD Elan 437 RDC R-321x SoC 438 SGI 320/540 (Visual Workstation) 439 STA2X11-based (e.g. Northville) 440 Moorestown MID devices 441 442 If you have one of these systems, or if you want to build a 443 generic distribution kernel, say Y here - otherwise say N. 444endif 445 446if X86_64 447config X86_EXTENDED_PLATFORM 448 bool "Support for extended (non-PC) x86 platforms" 449 default y 450 ---help--- 451 If you disable this option then the kernel will only support 452 standard PC platforms. (which covers the vast majority of 453 systems out there.) 454 455 If you enable this option then you'll be able to select support 456 for the following (non-PC) 64 bit x86 platforms: 457 Numascale NumaChip 458 ScaleMP vSMP 459 SGI Ultraviolet 460 461 If you have one of these systems, or if you want to build a 462 generic distribution kernel, say Y here - otherwise say N. 463endif 464# This is an alphabetically sorted list of 64 bit extended platforms 465# Please maintain the alphabetic order if and when there are additions 466config X86_NUMACHIP 467 bool "Numascale NumaChip" 468 depends on X86_64 469 depends on X86_EXTENDED_PLATFORM 470 depends on NUMA 471 depends on SMP 472 depends on X86_X2APIC 473 depends on PCI_MMCONFIG 474 ---help--- 475 Adds support for Numascale NumaChip large-SMP systems. Needed to 476 enable more than ~168 cores. 477 If you don't have one of these, you should say N here. 478 479config X86_VSMP 480 bool "ScaleMP vSMP" 481 select HYPERVISOR_GUEST 482 select PARAVIRT 483 depends on X86_64 && PCI 484 depends on X86_EXTENDED_PLATFORM 485 depends on SMP 486 ---help--- 487 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 488 supposed to run on these EM64T-based machines. Only choose this option 489 if you have one of these machines. 490 491config X86_UV 492 bool "SGI Ultraviolet" 493 depends on X86_64 494 depends on X86_EXTENDED_PLATFORM 495 depends on NUMA 496 depends on X86_X2APIC 497 depends on PCI 498 ---help--- 499 This option is needed in order to support SGI Ultraviolet systems. 500 If you don't have one of these, you should say N here. 501 502# Following is an alphabetically sorted list of 32 bit extended platforms 503# Please maintain the alphabetic order if and when there are additions 504 505config X86_GOLDFISH 506 bool "Goldfish (Virtual Platform)" 507 depends on X86_EXTENDED_PLATFORM 508 ---help--- 509 Enable support for the Goldfish virtual platform used primarily 510 for Android development. Unless you are building for the Android 511 Goldfish emulator say N here. 512 513config X86_INTEL_CE 514 bool "CE4100 TV platform" 515 depends on PCI 516 depends on PCI_GODIRECT 517 depends on X86_IO_APIC 518 depends on X86_32 519 depends on X86_EXTENDED_PLATFORM 520 select X86_REBOOTFIXUPS 521 select OF 522 select OF_EARLY_FLATTREE 523 ---help--- 524 Select for the Intel CE media processor (CE4100) SOC. 525 This option compiles in support for the CE4100 SOC for settop 526 boxes and media devices. 527 528config X86_INTEL_MID 529 bool "Intel MID platform support" 530 depends on X86_32 531 depends on X86_EXTENDED_PLATFORM 532 depends on X86_PLATFORM_DEVICES 533 depends on PCI 534 depends on PCI_GOANY 535 depends on X86_IO_APIC 536 select SFI 537 select I2C 538 select DW_APB_TIMER 539 select APB_TIMER 540 select INTEL_SCU_IPC 541 select MFD_INTEL_MSIC 542 ---help--- 543 Select to build a kernel capable of supporting Intel MID (Mobile 544 Internet Device) platform systems which do not have the PCI legacy 545 interfaces. If you are building for a PC class system say N here. 546 547 Intel MID platforms are based on an Intel processor and chipset which 548 consume less power than most of the x86 derivatives. 549 550config X86_INTEL_QUARK 551 bool "Intel Quark platform support" 552 depends on X86_32 553 depends on X86_EXTENDED_PLATFORM 554 depends on X86_PLATFORM_DEVICES 555 depends on X86_TSC 556 depends on PCI 557 depends on PCI_GOANY 558 depends on X86_IO_APIC 559 select IOSF_MBI 560 select INTEL_IMR 561 select COMMON_CLK 562 ---help--- 563 Select to include support for Quark X1000 SoC. 564 Say Y here if you have a Quark based system such as the Arduino 565 compatible Intel Galileo. 566 567config X86_INTEL_LPSS 568 bool "Intel Low Power Subsystem Support" 569 depends on ACPI 570 select COMMON_CLK 571 select PINCTRL 572 ---help--- 573 Select to build support for Intel Low Power Subsystem such as 574 found on Intel Lynxpoint PCH. Selecting this option enables 575 things like clock tree (common clock framework) and pincontrol 576 which are needed by the LPSS peripheral drivers. 577 578config X86_AMD_PLATFORM_DEVICE 579 bool "AMD ACPI2Platform devices support" 580 depends on ACPI 581 select COMMON_CLK 582 select PINCTRL 583 ---help--- 584 Select to interpret AMD specific ACPI device to platform device 585 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 586 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 587 implemented under PINCTRL subsystem. 588 589config IOSF_MBI 590 tristate "Intel SoC IOSF Sideband support for SoC platforms" 591 depends on PCI 592 ---help--- 593 This option enables sideband register access support for Intel SoC 594 platforms. On these platforms the IOSF sideband is used in lieu of 595 MSR's for some register accesses, mostly but not limited to thermal 596 and power. Drivers may query the availability of this device to 597 determine if they need the sideband in order to work on these 598 platforms. The sideband is available on the following SoC products. 599 This list is not meant to be exclusive. 600 - BayTrail 601 - Braswell 602 - Quark 603 604 You should say Y if you are running a kernel on one of these SoC's. 605 606config IOSF_MBI_DEBUG 607 bool "Enable IOSF sideband access through debugfs" 608 depends on IOSF_MBI && DEBUG_FS 609 ---help--- 610 Select this option to expose the IOSF sideband access registers (MCR, 611 MDR, MCRX) through debugfs to write and read register information from 612 different units on the SoC. This is most useful for obtaining device 613 state information for debug and analysis. As this is a general access 614 mechanism, users of this option would have specific knowledge of the 615 device they want to access. 616 617 If you don't require the option or are in doubt, say N. 618 619config X86_RDC321X 620 bool "RDC R-321x SoC" 621 depends on X86_32 622 depends on X86_EXTENDED_PLATFORM 623 select M486 624 select X86_REBOOTFIXUPS 625 ---help--- 626 This option is needed for RDC R-321x system-on-chip, also known 627 as R-8610-(G). 628 If you don't have one of these chips, you should say N here. 629 630config X86_32_NON_STANDARD 631 bool "Support non-standard 32-bit SMP architectures" 632 depends on X86_32 && SMP 633 depends on X86_EXTENDED_PLATFORM 634 ---help--- 635 This option compiles in the bigsmp and STA2X11 default 636 subarchitectures. It is intended for a generic binary 637 kernel. If you select them all, kernel will probe it one by 638 one and will fallback to default. 639 640# Alphabetically sorted list of Non standard 32 bit platforms 641 642config X86_SUPPORTS_MEMORY_FAILURE 643 def_bool y 644 # MCE code calls memory_failure(): 645 depends on X86_MCE 646 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 647 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 648 depends on X86_64 || !SPARSEMEM 649 select ARCH_SUPPORTS_MEMORY_FAILURE 650 651config STA2X11 652 bool "STA2X11 Companion Chip Support" 653 depends on X86_32_NON_STANDARD && PCI 654 select X86_DEV_DMA_OPS 655 select X86_DMA_REMAP 656 select SWIOTLB 657 select MFD_STA2X11 658 select ARCH_REQUIRE_GPIOLIB 659 default n 660 ---help--- 661 This adds support for boards based on the STA2X11 IO-Hub, 662 a.k.a. "ConneXt". The chip is used in place of the standard 663 PC chipset, so all "standard" peripherals are missing. If this 664 option is selected the kernel will still be able to boot on 665 standard PC machines. 666 667config X86_32_IRIS 668 tristate "Eurobraille/Iris poweroff module" 669 depends on X86_32 670 ---help--- 671 The Iris machines from EuroBraille do not have APM or ACPI support 672 to shut themselves down properly. A special I/O sequence is 673 needed to do so, which is what this module does at 674 kernel shutdown. 675 676 This is only for Iris machines from EuroBraille. 677 678 If unused, say N. 679 680config SCHED_OMIT_FRAME_POINTER 681 def_bool y 682 prompt "Single-depth WCHAN output" 683 depends on X86 684 ---help--- 685 Calculate simpler /proc/<PID>/wchan values. If this option 686 is disabled then wchan values will recurse back to the 687 caller function. This provides more accurate wchan values, 688 at the expense of slightly more scheduling overhead. 689 690 If in doubt, say "Y". 691 692menuconfig HYPERVISOR_GUEST 693 bool "Linux guest support" 694 ---help--- 695 Say Y here to enable options for running Linux under various hyper- 696 visors. This option enables basic hypervisor detection and platform 697 setup. 698 699 If you say N, all options in this submenu will be skipped and 700 disabled, and Linux guest support won't be built in. 701 702if HYPERVISOR_GUEST 703 704config PARAVIRT 705 bool "Enable paravirtualization code" 706 ---help--- 707 This changes the kernel so it can modify itself when it is run 708 under a hypervisor, potentially improving performance significantly 709 over full virtualization. However, when run without a hypervisor 710 the kernel is theoretically slower and slightly larger. 711 712config PARAVIRT_DEBUG 713 bool "paravirt-ops debugging" 714 depends on PARAVIRT && DEBUG_KERNEL 715 ---help--- 716 Enable to debug paravirt_ops internals. Specifically, BUG if 717 a paravirt_op is missing when it is called. 718 719config PARAVIRT_SPINLOCKS 720 bool "Paravirtualization layer for spinlocks" 721 depends on PARAVIRT && SMP 722 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS 723 ---help--- 724 Paravirtualized spinlocks allow a pvops backend to replace the 725 spinlock implementation with something virtualization-friendly 726 (for example, block the virtual CPU rather than spinning). 727 728 It has a minimal impact on native kernels and gives a nice performance 729 benefit on paravirtualized KVM / Xen kernels. 730 731 If you are unsure how to answer this question, answer Y. 732 733source "arch/x86/xen/Kconfig" 734 735config KVM_GUEST 736 bool "KVM Guest support (including kvmclock)" 737 depends on PARAVIRT 738 select PARAVIRT_CLOCK 739 default y 740 ---help--- 741 This option enables various optimizations for running under the KVM 742 hypervisor. It includes a paravirtualized clock, so that instead 743 of relying on a PIT (or probably other) emulation by the 744 underlying device model, the host provides the guest with 745 timing infrastructure such as time of day, and system time 746 747config KVM_DEBUG_FS 748 bool "Enable debug information for KVM Guests in debugfs" 749 depends on KVM_GUEST && DEBUG_FS 750 default n 751 ---help--- 752 This option enables collection of various statistics for KVM guest. 753 Statistics are displayed in debugfs filesystem. Enabling this option 754 may incur significant overhead. 755 756source "arch/x86/lguest/Kconfig" 757 758config PARAVIRT_TIME_ACCOUNTING 759 bool "Paravirtual steal time accounting" 760 depends on PARAVIRT 761 default n 762 ---help--- 763 Select this option to enable fine granularity task steal time 764 accounting. Time spent executing other tasks in parallel with 765 the current vCPU is discounted from the vCPU power. To account for 766 that, there can be a small performance impact. 767 768 If in doubt, say N here. 769 770config PARAVIRT_CLOCK 771 bool 772 773endif #HYPERVISOR_GUEST 774 775config NO_BOOTMEM 776 def_bool y 777 778source "arch/x86/Kconfig.cpu" 779 780config HPET_TIMER 781 def_bool X86_64 782 prompt "HPET Timer Support" if X86_32 783 ---help--- 784 Use the IA-PC HPET (High Precision Event Timer) to manage 785 time in preference to the PIT and RTC, if a HPET is 786 present. 787 HPET is the next generation timer replacing legacy 8254s. 788 The HPET provides a stable time base on SMP 789 systems, unlike the TSC, but it is more expensive to access, 790 as it is off-chip. You can find the HPET spec at 791 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 792 793 You can safely choose Y here. However, HPET will only be 794 activated if the platform and the BIOS support this feature. 795 Otherwise the 8254 will be used for timing services. 796 797 Choose N to continue using the legacy 8254 timer. 798 799config HPET_EMULATE_RTC 800 def_bool y 801 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 802 803config APB_TIMER 804 def_bool y if X86_INTEL_MID 805 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 806 select DW_APB_TIMER 807 depends on X86_INTEL_MID && SFI 808 help 809 APB timer is the replacement for 8254, HPET on X86 MID platforms. 810 The APBT provides a stable time base on SMP 811 systems, unlike the TSC, but it is more expensive to access, 812 as it is off-chip. APB timers are always running regardless of CPU 813 C states, they are used as per CPU clockevent device when possible. 814 815# Mark as expert because too many people got it wrong. 816# The code disables itself when not needed. 817config DMI 818 default y 819 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 820 bool "Enable DMI scanning" if EXPERT 821 ---help--- 822 Enabled scanning of DMI to identify machine quirks. Say Y 823 here unless you have verified that your setup is not 824 affected by entries in the DMI blacklist. Required by PNP 825 BIOS code. 826 827config GART_IOMMU 828 bool "Old AMD GART IOMMU support" 829 select SWIOTLB 830 depends on X86_64 && PCI && AMD_NB 831 ---help--- 832 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 833 GART based hardware IOMMUs. 834 835 The GART supports full DMA access for devices with 32-bit access 836 limitations, on systems with more than 3 GB. This is usually needed 837 for USB, sound, many IDE/SATA chipsets and some other devices. 838 839 Newer systems typically have a modern AMD IOMMU, supported via 840 the CONFIG_AMD_IOMMU=y config option. 841 842 In normal configurations this driver is only active when needed: 843 there's more than 3 GB of memory and the system contains a 844 32-bit limited device. 845 846 If unsure, say Y. 847 848config CALGARY_IOMMU 849 bool "IBM Calgary IOMMU support" 850 select SWIOTLB 851 depends on X86_64 && PCI 852 ---help--- 853 Support for hardware IOMMUs in IBM's xSeries x366 and x460 854 systems. Needed to run systems with more than 3GB of memory 855 properly with 32-bit PCI devices that do not support DAC 856 (Double Address Cycle). Calgary also supports bus level 857 isolation, where all DMAs pass through the IOMMU. This 858 prevents them from going anywhere except their intended 859 destination. This catches hard-to-find kernel bugs and 860 mis-behaving drivers and devices that do not use the DMA-API 861 properly to set up their DMA buffers. The IOMMU can be 862 turned off at boot time with the iommu=off parameter. 863 Normally the kernel will make the right choice by itself. 864 If unsure, say Y. 865 866config CALGARY_IOMMU_ENABLED_BY_DEFAULT 867 def_bool y 868 prompt "Should Calgary be enabled by default?" 869 depends on CALGARY_IOMMU 870 ---help--- 871 Should Calgary be enabled by default? if you choose 'y', Calgary 872 will be used (if it exists). If you choose 'n', Calgary will not be 873 used even if it exists. If you choose 'n' and would like to use 874 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 875 If unsure, say Y. 876 877# need this always selected by IOMMU for the VIA workaround 878config SWIOTLB 879 def_bool y if X86_64 880 ---help--- 881 Support for software bounce buffers used on x86-64 systems 882 which don't have a hardware IOMMU. Using this PCI devices 883 which can only access 32-bits of memory can be used on systems 884 with more than 3 GB of memory. 885 If unsure, say Y. 886 887config IOMMU_HELPER 888 def_bool y 889 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 890 891config MAXSMP 892 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 893 depends on X86_64 && SMP && DEBUG_KERNEL 894 select CPUMASK_OFFSTACK 895 ---help--- 896 Enable maximum number of CPUS and NUMA Nodes for this architecture. 897 If unsure, say N. 898 899config NR_CPUS 900 int "Maximum number of CPUs" if SMP && !MAXSMP 901 range 2 8 if SMP && X86_32 && !X86_BIGSMP 902 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 903 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 904 default "1" if !SMP 905 default "8192" if MAXSMP 906 default "32" if SMP && X86_BIGSMP 907 default "8" if SMP && X86_32 908 default "64" if SMP 909 ---help--- 910 This allows you to specify the maximum number of CPUs which this 911 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 912 supported value is 8192, otherwise the maximum value is 512. The 913 minimum value which makes sense is 2. 914 915 This is purely to save memory - each supported CPU adds 916 approximately eight kilobytes to the kernel image. 917 918config SCHED_SMT 919 def_bool y if SMP 920 921config SCHED_MC 922 def_bool y 923 prompt "Multi-core scheduler support" 924 depends on SMP 925 ---help--- 926 Multi-core scheduler support improves the CPU scheduler's decision 927 making when dealing with multi-core CPU chips at a cost of slightly 928 increased overhead in some places. If unsure say N here. 929 930source "kernel/Kconfig.preempt" 931 932config UP_LATE_INIT 933 def_bool y 934 depends on !SMP && X86_LOCAL_APIC 935 936config X86_UP_APIC 937 bool "Local APIC support on uniprocessors" if !PCI_MSI 938 default PCI_MSI 939 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 940 ---help--- 941 A local APIC (Advanced Programmable Interrupt Controller) is an 942 integrated interrupt controller in the CPU. If you have a single-CPU 943 system which has a processor with a local APIC, you can say Y here to 944 enable and use it. If you say Y here even though your machine doesn't 945 have a local APIC, then the kernel will still run with no slowdown at 946 all. The local APIC supports CPU-generated self-interrupts (timer, 947 performance counters), and the NMI watchdog which detects hard 948 lockups. 949 950config X86_UP_IOAPIC 951 bool "IO-APIC support on uniprocessors" 952 depends on X86_UP_APIC 953 ---help--- 954 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 955 SMP-capable replacement for PC-style interrupt controllers. Most 956 SMP systems and many recent uniprocessor systems have one. 957 958 If you have a single-CPU system with an IO-APIC, you can say Y here 959 to use it. If you say Y here even though your machine doesn't have 960 an IO-APIC, then the kernel will still run with no slowdown at all. 961 962config X86_LOCAL_APIC 963 def_bool y 964 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 965 select IRQ_DOMAIN_HIERARCHY 966 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 967 968config X86_IO_APIC 969 def_bool y 970 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 971 972config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 973 bool "Reroute for broken boot IRQs" 974 depends on X86_IO_APIC 975 ---help--- 976 This option enables a workaround that fixes a source of 977 spurious interrupts. This is recommended when threaded 978 interrupt handling is used on systems where the generation of 979 superfluous "boot interrupts" cannot be disabled. 980 981 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 982 entry in the chipset's IO-APIC is masked (as, e.g. the RT 983 kernel does during interrupt handling). On chipsets where this 984 boot IRQ generation cannot be disabled, this workaround keeps 985 the original IRQ line masked so that only the equivalent "boot 986 IRQ" is delivered to the CPUs. The workaround also tells the 987 kernel to set up the IRQ handler on the boot IRQ line. In this 988 way only one interrupt is delivered to the kernel. Otherwise 989 the spurious second interrupt may cause the kernel to bring 990 down (vital) interrupt lines. 991 992 Only affects "broken" chipsets. Interrupt sharing may be 993 increased on these systems. 994 995config X86_MCE 996 bool "Machine Check / overheating reporting" 997 select GENERIC_ALLOCATOR 998 default y 999 ---help--- 1000 Machine Check support allows the processor to notify the 1001 kernel if it detects a problem (e.g. overheating, data corruption). 1002 The action the kernel takes depends on the severity of the problem, 1003 ranging from warning messages to halting the machine. 1004 1005config X86_MCE_INTEL 1006 def_bool y 1007 prompt "Intel MCE features" 1008 depends on X86_MCE && X86_LOCAL_APIC 1009 ---help--- 1010 Additional support for intel specific MCE features such as 1011 the thermal monitor. 1012 1013config X86_MCE_AMD 1014 def_bool y 1015 prompt "AMD MCE features" 1016 depends on X86_MCE && X86_LOCAL_APIC 1017 ---help--- 1018 Additional support for AMD specific MCE features such as 1019 the DRAM Error Threshold. 1020 1021config X86_ANCIENT_MCE 1022 bool "Support for old Pentium 5 / WinChip machine checks" 1023 depends on X86_32 && X86_MCE 1024 ---help--- 1025 Include support for machine check handling on old Pentium 5 or WinChip 1026 systems. These typically need to be enabled explicitly on the command 1027 line. 1028 1029config X86_MCE_THRESHOLD 1030 depends on X86_MCE_AMD || X86_MCE_INTEL 1031 def_bool y 1032 1033config X86_MCE_INJECT 1034 depends on X86_MCE && X86_LOCAL_APIC 1035 tristate "Machine check injector support" 1036 ---help--- 1037 Provide support for injecting machine checks for testing purposes. 1038 If you don't know what a machine check is and you don't do kernel 1039 QA it is safe to say n. 1040 1041config X86_THERMAL_VECTOR 1042 def_bool y 1043 depends on X86_MCE_INTEL 1044 1045config X86_LEGACY_VM86 1046 bool "Legacy VM86 support" 1047 default n 1048 depends on X86_32 1049 ---help--- 1050 This option allows user programs to put the CPU into V8086 1051 mode, which is an 80286-era approximation of 16-bit real mode. 1052 1053 Some very old versions of X and/or vbetool require this option 1054 for user mode setting. Similarly, DOSEMU will use it if 1055 available to accelerate real mode DOS programs. However, any 1056 recent version of DOSEMU, X, or vbetool should be fully 1057 functional even without kernel VM86 support, as they will all 1058 fall back to software emulation. Nevertheless, if you are using 1059 a 16-bit DOS program where 16-bit performance matters, vm86 1060 mode might be faster than emulation and you might want to 1061 enable this option. 1062 1063 Note that any app that works on a 64-bit kernel is unlikely to 1064 need this option, as 64-bit kernels don't, and can't, support 1065 V8086 mode. This option is also unrelated to 16-bit protected 1066 mode and is not needed to run most 16-bit programs under Wine. 1067 1068 Enabling this option increases the complexity of the kernel 1069 and slows down exception handling a tiny bit. 1070 1071 If unsure, say N here. 1072 1073config VM86 1074 bool 1075 default X86_LEGACY_VM86 1076 1077config X86_16BIT 1078 bool "Enable support for 16-bit segments" if EXPERT 1079 default y 1080 depends on MODIFY_LDT_SYSCALL 1081 ---help--- 1082 This option is required by programs like Wine to run 16-bit 1083 protected mode legacy code on x86 processors. Disabling 1084 this option saves about 300 bytes on i386, or around 6K text 1085 plus 16K runtime memory on x86-64, 1086 1087config X86_ESPFIX32 1088 def_bool y 1089 depends on X86_16BIT && X86_32 1090 1091config X86_ESPFIX64 1092 def_bool y 1093 depends on X86_16BIT && X86_64 1094 1095config X86_VSYSCALL_EMULATION 1096 bool "Enable vsyscall emulation" if EXPERT 1097 default y 1098 depends on X86_64 1099 ---help--- 1100 This enables emulation of the legacy vsyscall page. Disabling 1101 it is roughly equivalent to booting with vsyscall=none, except 1102 that it will also disable the helpful warning if a program 1103 tries to use a vsyscall. With this option set to N, offending 1104 programs will just segfault, citing addresses of the form 1105 0xffffffffff600?00. 1106 1107 This option is required by many programs built before 2013, and 1108 care should be used even with newer programs if set to N. 1109 1110 Disabling this option saves about 7K of kernel size and 1111 possibly 4K of additional runtime pagetable memory. 1112 1113config TOSHIBA 1114 tristate "Toshiba Laptop support" 1115 depends on X86_32 1116 ---help--- 1117 This adds a driver to safely access the System Management Mode of 1118 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1119 not work on models with a Phoenix BIOS. The System Management Mode 1120 is used to set the BIOS and power saving options on Toshiba portables. 1121 1122 For information on utilities to make use of this driver see the 1123 Toshiba Linux utilities web site at: 1124 <http://www.buzzard.org.uk/toshiba/>. 1125 1126 Say Y if you intend to run this kernel on a Toshiba portable. 1127 Say N otherwise. 1128 1129config I8K 1130 tristate "Dell i8k legacy laptop support" 1131 select HWMON 1132 select SENSORS_DELL_SMM 1133 ---help--- 1134 This option enables legacy /proc/i8k userspace interface in hwmon 1135 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1136 temperature and allows controlling fan speeds of Dell laptops via 1137 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1138 it reports also power and hotkey status. For fan speed control is 1139 needed userspace package i8kutils. 1140 1141 Say Y if you intend to run this kernel on old Dell laptops or want to 1142 use userspace package i8kutils. 1143 Say N otherwise. 1144 1145config X86_REBOOTFIXUPS 1146 bool "Enable X86 board specific fixups for reboot" 1147 depends on X86_32 1148 ---help--- 1149 This enables chipset and/or board specific fixups to be done 1150 in order to get reboot to work correctly. This is only needed on 1151 some combinations of hardware and BIOS. The symptom, for which 1152 this config is intended, is when reboot ends with a stalled/hung 1153 system. 1154 1155 Currently, the only fixup is for the Geode machines using 1156 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1157 1158 Say Y if you want to enable the fixup. Currently, it's safe to 1159 enable this option even if you don't need it. 1160 Say N otherwise. 1161 1162config MICROCODE 1163 bool "CPU microcode loading support" 1164 default y 1165 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1166 select FW_LOADER 1167 ---help--- 1168 If you say Y here, you will be able to update the microcode on 1169 Intel and AMD processors. The Intel support is for the IA32 family, 1170 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1171 AMD support is for families 0x10 and later. You will obviously need 1172 the actual microcode binary data itself which is not shipped with 1173 the Linux kernel. 1174 1175 The preferred method to load microcode from a detached initrd is described 1176 in Documentation/x86/early-microcode.txt. For that you need to enable 1177 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1178 initrd for microcode blobs. 1179 1180 In addition, you can build-in the microcode into the kernel. For that you 1181 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 1182 to the CONFIG_EXTRA_FIRMWARE config option. 1183 1184config MICROCODE_INTEL 1185 bool "Intel microcode loading support" 1186 depends on MICROCODE 1187 default MICROCODE 1188 select FW_LOADER 1189 ---help--- 1190 This options enables microcode patch loading support for Intel 1191 processors. 1192 1193 For the current Intel microcode data package go to 1194 <https://downloadcenter.intel.com> and search for 1195 'Linux Processor Microcode Data File'. 1196 1197config MICROCODE_AMD 1198 bool "AMD microcode loading support" 1199 depends on MICROCODE 1200 select FW_LOADER 1201 ---help--- 1202 If you select this option, microcode patch loading support for AMD 1203 processors will be enabled. 1204 1205config MICROCODE_OLD_INTERFACE 1206 def_bool y 1207 depends on MICROCODE 1208 1209config X86_MSR 1210 tristate "/dev/cpu/*/msr - Model-specific register support" 1211 ---help--- 1212 This device gives privileged processes access to the x86 1213 Model-Specific Registers (MSRs). It is a character device with 1214 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1215 MSR accesses are directed to a specific CPU on multi-processor 1216 systems. 1217 1218config X86_CPUID 1219 tristate "/dev/cpu/*/cpuid - CPU information support" 1220 ---help--- 1221 This device gives processes access to the x86 CPUID instruction to 1222 be executed on a specific processor. It is a character device 1223 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1224 /dev/cpu/31/cpuid. 1225 1226choice 1227 prompt "High Memory Support" 1228 default HIGHMEM4G 1229 depends on X86_32 1230 1231config NOHIGHMEM 1232 bool "off" 1233 ---help--- 1234 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1235 However, the address space of 32-bit x86 processors is only 4 1236 Gigabytes large. That means that, if you have a large amount of 1237 physical memory, not all of it can be "permanently mapped" by the 1238 kernel. The physical memory that's not permanently mapped is called 1239 "high memory". 1240 1241 If you are compiling a kernel which will never run on a machine with 1242 more than 1 Gigabyte total physical RAM, answer "off" here (default 1243 choice and suitable for most users). This will result in a "3GB/1GB" 1244 split: 3GB are mapped so that each process sees a 3GB virtual memory 1245 space and the remaining part of the 4GB virtual memory space is used 1246 by the kernel to permanently map as much physical memory as 1247 possible. 1248 1249 If the machine has between 1 and 4 Gigabytes physical RAM, then 1250 answer "4GB" here. 1251 1252 If more than 4 Gigabytes is used then answer "64GB" here. This 1253 selection turns Intel PAE (Physical Address Extension) mode on. 1254 PAE implements 3-level paging on IA32 processors. PAE is fully 1255 supported by Linux, PAE mode is implemented on all recent Intel 1256 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1257 then the kernel will not boot on CPUs that don't support PAE! 1258 1259 The actual amount of total physical memory will either be 1260 auto detected or can be forced by using a kernel command line option 1261 such as "mem=256M". (Try "man bootparam" or see the documentation of 1262 your boot loader (lilo or loadlin) about how to pass options to the 1263 kernel at boot time.) 1264 1265 If unsure, say "off". 1266 1267config HIGHMEM4G 1268 bool "4GB" 1269 ---help--- 1270 Select this if you have a 32-bit processor and between 1 and 4 1271 gigabytes of physical RAM. 1272 1273config HIGHMEM64G 1274 bool "64GB" 1275 depends on !M486 1276 select X86_PAE 1277 ---help--- 1278 Select this if you have a 32-bit processor and more than 4 1279 gigabytes of physical RAM. 1280 1281endchoice 1282 1283choice 1284 prompt "Memory split" if EXPERT 1285 default VMSPLIT_3G 1286 depends on X86_32 1287 ---help--- 1288 Select the desired split between kernel and user memory. 1289 1290 If the address range available to the kernel is less than the 1291 physical memory installed, the remaining memory will be available 1292 as "high memory". Accessing high memory is a little more costly 1293 than low memory, as it needs to be mapped into the kernel first. 1294 Note that increasing the kernel address space limits the range 1295 available to user programs, making the address space there 1296 tighter. Selecting anything other than the default 3G/1G split 1297 will also likely make your kernel incompatible with binary-only 1298 kernel modules. 1299 1300 If you are not absolutely sure what you are doing, leave this 1301 option alone! 1302 1303 config VMSPLIT_3G 1304 bool "3G/1G user/kernel split" 1305 config VMSPLIT_3G_OPT 1306 depends on !X86_PAE 1307 bool "3G/1G user/kernel split (for full 1G low memory)" 1308 config VMSPLIT_2G 1309 bool "2G/2G user/kernel split" 1310 config VMSPLIT_2G_OPT 1311 depends on !X86_PAE 1312 bool "2G/2G user/kernel split (for full 2G low memory)" 1313 config VMSPLIT_1G 1314 bool "1G/3G user/kernel split" 1315endchoice 1316 1317config PAGE_OFFSET 1318 hex 1319 default 0xB0000000 if VMSPLIT_3G_OPT 1320 default 0x80000000 if VMSPLIT_2G 1321 default 0x78000000 if VMSPLIT_2G_OPT 1322 default 0x40000000 if VMSPLIT_1G 1323 default 0xC0000000 1324 depends on X86_32 1325 1326config HIGHMEM 1327 def_bool y 1328 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1329 1330config X86_PAE 1331 bool "PAE (Physical Address Extension) Support" 1332 depends on X86_32 && !HIGHMEM4G 1333 select SWIOTLB 1334 ---help--- 1335 PAE is required for NX support, and furthermore enables 1336 larger swapspace support for non-overcommit purposes. It 1337 has the cost of more pagetable lookup overhead, and also 1338 consumes more pagetable space per process. 1339 1340config ARCH_PHYS_ADDR_T_64BIT 1341 def_bool y 1342 depends on X86_64 || X86_PAE 1343 1344config ARCH_DMA_ADDR_T_64BIT 1345 def_bool y 1346 depends on X86_64 || HIGHMEM64G 1347 1348config X86_DIRECT_GBPAGES 1349 def_bool y 1350 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1351 ---help--- 1352 Certain kernel features effectively disable kernel 1353 linear 1 GB mappings (even if the CPU otherwise 1354 supports them), so don't confuse the user by printing 1355 that we have them enabled. 1356 1357# Common NUMA Features 1358config NUMA 1359 bool "Numa Memory Allocation and Scheduler Support" 1360 depends on SMP 1361 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1362 default y if X86_BIGSMP 1363 ---help--- 1364 Enable NUMA (Non Uniform Memory Access) support. 1365 1366 The kernel will try to allocate memory used by a CPU on the 1367 local memory controller of the CPU and add some more 1368 NUMA awareness to the kernel. 1369 1370 For 64-bit this is recommended if the system is Intel Core i7 1371 (or later), AMD Opteron, or EM64T NUMA. 1372 1373 For 32-bit this is only needed if you boot a 32-bit 1374 kernel on a 64-bit NUMA platform. 1375 1376 Otherwise, you should say N. 1377 1378config AMD_NUMA 1379 def_bool y 1380 prompt "Old style AMD Opteron NUMA detection" 1381 depends on X86_64 && NUMA && PCI 1382 ---help--- 1383 Enable AMD NUMA node topology detection. You should say Y here if 1384 you have a multi processor AMD system. This uses an old method to 1385 read the NUMA configuration directly from the builtin Northbridge 1386 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1387 which also takes priority if both are compiled in. 1388 1389config X86_64_ACPI_NUMA 1390 def_bool y 1391 prompt "ACPI NUMA detection" 1392 depends on X86_64 && NUMA && ACPI && PCI 1393 select ACPI_NUMA 1394 ---help--- 1395 Enable ACPI SRAT based node topology detection. 1396 1397# Some NUMA nodes have memory ranges that span 1398# other nodes. Even though a pfn is valid and 1399# between a node's start and end pfns, it may not 1400# reside on that node. See memmap_init_zone() 1401# for details. 1402config NODES_SPAN_OTHER_NODES 1403 def_bool y 1404 depends on X86_64_ACPI_NUMA 1405 1406config NUMA_EMU 1407 bool "NUMA emulation" 1408 depends on NUMA 1409 ---help--- 1410 Enable NUMA emulation. A flat machine will be split 1411 into virtual nodes when booted with "numa=fake=N", where N is the 1412 number of nodes. This is only useful for debugging. 1413 1414config NODES_SHIFT 1415 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1416 range 1 10 1417 default "10" if MAXSMP 1418 default "6" if X86_64 1419 default "3" 1420 depends on NEED_MULTIPLE_NODES 1421 ---help--- 1422 Specify the maximum number of NUMA Nodes available on the target 1423 system. Increases memory reserved to accommodate various tables. 1424 1425config ARCH_HAVE_MEMORY_PRESENT 1426 def_bool y 1427 depends on X86_32 && DISCONTIGMEM 1428 1429config NEED_NODE_MEMMAP_SIZE 1430 def_bool y 1431 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1432 1433config ARCH_FLATMEM_ENABLE 1434 def_bool y 1435 depends on X86_32 && !NUMA 1436 1437config ARCH_DISCONTIGMEM_ENABLE 1438 def_bool y 1439 depends on NUMA && X86_32 1440 1441config ARCH_DISCONTIGMEM_DEFAULT 1442 def_bool y 1443 depends on NUMA && X86_32 1444 1445config ARCH_SPARSEMEM_ENABLE 1446 def_bool y 1447 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1448 select SPARSEMEM_STATIC if X86_32 1449 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1450 1451config ARCH_SPARSEMEM_DEFAULT 1452 def_bool y 1453 depends on X86_64 1454 1455config ARCH_SELECT_MEMORY_MODEL 1456 def_bool y 1457 depends on ARCH_SPARSEMEM_ENABLE 1458 1459config ARCH_MEMORY_PROBE 1460 bool "Enable sysfs memory/probe interface" 1461 depends on X86_64 && MEMORY_HOTPLUG 1462 help 1463 This option enables a sysfs memory/probe interface for testing. 1464 See Documentation/memory-hotplug.txt for more information. 1465 If you are unsure how to answer this question, answer N. 1466 1467config ARCH_PROC_KCORE_TEXT 1468 def_bool y 1469 depends on X86_64 && PROC_KCORE 1470 1471config ILLEGAL_POINTER_VALUE 1472 hex 1473 default 0 if X86_32 1474 default 0xdead000000000000 if X86_64 1475 1476source "mm/Kconfig" 1477 1478config X86_PMEM_LEGACY_DEVICE 1479 bool 1480 1481config X86_PMEM_LEGACY 1482 tristate "Support non-standard NVDIMMs and ADR protected memory" 1483 depends on PHYS_ADDR_T_64BIT 1484 depends on BLK_DEV 1485 select X86_PMEM_LEGACY_DEVICE 1486 select LIBNVDIMM 1487 help 1488 Treat memory marked using the non-standard e820 type of 12 as used 1489 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1490 The kernel will offer these regions to the 'pmem' driver so 1491 they can be used for persistent storage. 1492 1493 Say Y if unsure. 1494 1495config HIGHPTE 1496 bool "Allocate 3rd-level pagetables from highmem" 1497 depends on HIGHMEM 1498 ---help--- 1499 The VM uses one page table entry for each page of physical memory. 1500 For systems with a lot of RAM, this can be wasteful of precious 1501 low memory. Setting this option will put user-space page table 1502 entries in high memory. 1503 1504config X86_CHECK_BIOS_CORRUPTION 1505 bool "Check for low memory corruption" 1506 ---help--- 1507 Periodically check for memory corruption in low memory, which 1508 is suspected to be caused by BIOS. Even when enabled in the 1509 configuration, it is disabled at runtime. Enable it by 1510 setting "memory_corruption_check=1" on the kernel command 1511 line. By default it scans the low 64k of memory every 60 1512 seconds; see the memory_corruption_check_size and 1513 memory_corruption_check_period parameters in 1514 Documentation/kernel-parameters.txt to adjust this. 1515 1516 When enabled with the default parameters, this option has 1517 almost no overhead, as it reserves a relatively small amount 1518 of memory and scans it infrequently. It both detects corruption 1519 and prevents it from affecting the running system. 1520 1521 It is, however, intended as a diagnostic tool; if repeatable 1522 BIOS-originated corruption always affects the same memory, 1523 you can use memmap= to prevent the kernel from using that 1524 memory. 1525 1526config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1527 bool "Set the default setting of memory_corruption_check" 1528 depends on X86_CHECK_BIOS_CORRUPTION 1529 default y 1530 ---help--- 1531 Set whether the default state of memory_corruption_check is 1532 on or off. 1533 1534config X86_RESERVE_LOW 1535 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1536 default 64 1537 range 4 640 1538 ---help--- 1539 Specify the amount of low memory to reserve for the BIOS. 1540 1541 The first page contains BIOS data structures that the kernel 1542 must not use, so that page must always be reserved. 1543 1544 By default we reserve the first 64K of physical RAM, as a 1545 number of BIOSes are known to corrupt that memory range 1546 during events such as suspend/resume or monitor cable 1547 insertion, so it must not be used by the kernel. 1548 1549 You can set this to 4 if you are absolutely sure that you 1550 trust the BIOS to get all its memory reservations and usages 1551 right. If you know your BIOS have problems beyond the 1552 default 64K area, you can set this to 640 to avoid using the 1553 entire low memory range. 1554 1555 If you have doubts about the BIOS (e.g. suspend/resume does 1556 not work or there's kernel crashes after certain hardware 1557 hotplug events) then you might want to enable 1558 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1559 typical corruption patterns. 1560 1561 Leave this to the default value of 64 if you are unsure. 1562 1563config MATH_EMULATION 1564 bool 1565 depends on MODIFY_LDT_SYSCALL 1566 prompt "Math emulation" if X86_32 1567 ---help--- 1568 Linux can emulate a math coprocessor (used for floating point 1569 operations) if you don't have one. 486DX and Pentium processors have 1570 a math coprocessor built in, 486SX and 386 do not, unless you added 1571 a 487DX or 387, respectively. (The messages during boot time can 1572 give you some hints here ["man dmesg"].) Everyone needs either a 1573 coprocessor or this emulation. 1574 1575 If you don't have a math coprocessor, you need to say Y here; if you 1576 say Y here even though you have a coprocessor, the coprocessor will 1577 be used nevertheless. (This behavior can be changed with the kernel 1578 command line option "no387", which comes handy if your coprocessor 1579 is broken. Try "man bootparam" or see the documentation of your boot 1580 loader (lilo or loadlin) about how to pass options to the kernel at 1581 boot time.) This means that it is a good idea to say Y here if you 1582 intend to use this kernel on different machines. 1583 1584 More information about the internals of the Linux math coprocessor 1585 emulation can be found in <file:arch/x86/math-emu/README>. 1586 1587 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1588 kernel, it won't hurt. 1589 1590config MTRR 1591 def_bool y 1592 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1593 ---help--- 1594 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1595 the Memory Type Range Registers (MTRRs) may be used to control 1596 processor access to memory ranges. This is most useful if you have 1597 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1598 allows bus write transfers to be combined into a larger transfer 1599 before bursting over the PCI/AGP bus. This can increase performance 1600 of image write operations 2.5 times or more. Saying Y here creates a 1601 /proc/mtrr file which may be used to manipulate your processor's 1602 MTRRs. Typically the X server should use this. 1603 1604 This code has a reasonably generic interface so that similar 1605 control registers on other processors can be easily supported 1606 as well: 1607 1608 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1609 Registers (ARRs) which provide a similar functionality to MTRRs. For 1610 these, the ARRs are used to emulate the MTRRs. 1611 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1612 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1613 write-combining. All of these processors are supported by this code 1614 and it makes sense to say Y here if you have one of them. 1615 1616 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1617 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1618 can lead to all sorts of problems, so it's good to say Y here. 1619 1620 You can safely say Y even if your machine doesn't have MTRRs, you'll 1621 just add about 9 KB to your kernel. 1622 1623 See <file:Documentation/x86/mtrr.txt> for more information. 1624 1625config MTRR_SANITIZER 1626 def_bool y 1627 prompt "MTRR cleanup support" 1628 depends on MTRR 1629 ---help--- 1630 Convert MTRR layout from continuous to discrete, so X drivers can 1631 add writeback entries. 1632 1633 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1634 The largest mtrr entry size for a continuous block can be set with 1635 mtrr_chunk_size. 1636 1637 If unsure, say Y. 1638 1639config MTRR_SANITIZER_ENABLE_DEFAULT 1640 int "MTRR cleanup enable value (0-1)" 1641 range 0 1 1642 default "0" 1643 depends on MTRR_SANITIZER 1644 ---help--- 1645 Enable mtrr cleanup default value 1646 1647config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1648 int "MTRR cleanup spare reg num (0-7)" 1649 range 0 7 1650 default "1" 1651 depends on MTRR_SANITIZER 1652 ---help--- 1653 mtrr cleanup spare entries default, it can be changed via 1654 mtrr_spare_reg_nr=N on the kernel command line. 1655 1656config X86_PAT 1657 def_bool y 1658 prompt "x86 PAT support" if EXPERT 1659 depends on MTRR 1660 ---help--- 1661 Use PAT attributes to setup page level cache control. 1662 1663 PATs are the modern equivalents of MTRRs and are much more 1664 flexible than MTRRs. 1665 1666 Say N here if you see bootup problems (boot crash, boot hang, 1667 spontaneous reboots) or a non-working video driver. 1668 1669 If unsure, say Y. 1670 1671config ARCH_USES_PG_UNCACHED 1672 def_bool y 1673 depends on X86_PAT 1674 1675config ARCH_RANDOM 1676 def_bool y 1677 prompt "x86 architectural random number generator" if EXPERT 1678 ---help--- 1679 Enable the x86 architectural RDRAND instruction 1680 (Intel Bull Mountain technology) to generate random numbers. 1681 If supported, this is a high bandwidth, cryptographically 1682 secure hardware random number generator. 1683 1684config X86_SMAP 1685 def_bool y 1686 prompt "Supervisor Mode Access Prevention" if EXPERT 1687 ---help--- 1688 Supervisor Mode Access Prevention (SMAP) is a security 1689 feature in newer Intel processors. There is a small 1690 performance cost if this enabled and turned on; there is 1691 also a small increase in the kernel size if this is enabled. 1692 1693 If unsure, say Y. 1694 1695config X86_INTEL_MPX 1696 prompt "Intel MPX (Memory Protection Extensions)" 1697 def_bool n 1698 depends on CPU_SUP_INTEL 1699 ---help--- 1700 MPX provides hardware features that can be used in 1701 conjunction with compiler-instrumented code to check 1702 memory references. It is designed to detect buffer 1703 overflow or underflow bugs. 1704 1705 This option enables running applications which are 1706 instrumented or otherwise use MPX. It does not use MPX 1707 itself inside the kernel or to protect the kernel 1708 against bad memory references. 1709 1710 Enabling this option will make the kernel larger: 1711 ~8k of kernel text and 36 bytes of data on a 64-bit 1712 defconfig. It adds a long to the 'mm_struct' which 1713 will increase the kernel memory overhead of each 1714 process and adds some branches to paths used during 1715 exec() and munmap(). 1716 1717 For details, see Documentation/x86/intel_mpx.txt 1718 1719 If unsure, say N. 1720 1721choice 1722 prompt "TSX enable mode" 1723 depends on CPU_SUP_INTEL 1724 default X86_INTEL_TSX_MODE_OFF 1725 help 1726 Intel's TSX (Transactional Synchronization Extensions) feature 1727 allows to optimize locking protocols through lock elision which 1728 can lead to a noticeable performance boost. 1729 1730 On the other hand it has been shown that TSX can be exploited 1731 to form side channel attacks (e.g. TAA) and chances are there 1732 will be more of those attacks discovered in the future. 1733 1734 Therefore TSX is not enabled by default (aka tsx=off). An admin 1735 might override this decision by tsx=on the command line parameter. 1736 Even with TSX enabled, the kernel will attempt to enable the best 1737 possible TAA mitigation setting depending on the microcode available 1738 for the particular machine. 1739 1740 This option allows to set the default tsx mode between tsx=on, =off 1741 and =auto. See Documentation/kernel-parameters.txt for more 1742 details. 1743 1744 Say off if not sure, auto if TSX is in use but it should be used on safe 1745 platforms or on if TSX is in use and the security aspect of tsx is not 1746 relevant. 1747 1748config X86_INTEL_TSX_MODE_OFF 1749 bool "off" 1750 help 1751 TSX is disabled if possible - equals to tsx=off command line parameter. 1752 1753config X86_INTEL_TSX_MODE_ON 1754 bool "on" 1755 help 1756 TSX is always enabled on TSX capable HW - equals the tsx=on command 1757 line parameter. 1758 1759config X86_INTEL_TSX_MODE_AUTO 1760 bool "auto" 1761 help 1762 TSX is enabled on TSX capable HW that is believed to be safe against 1763 side channel attacks- equals the tsx=auto command line parameter. 1764endchoice 1765 1766config EFI 1767 bool "EFI runtime service support" 1768 depends on ACPI 1769 select UCS2_STRING 1770 select EFI_RUNTIME_WRAPPERS 1771 ---help--- 1772 This enables the kernel to use EFI runtime services that are 1773 available (such as the EFI variable services). 1774 1775 This option is only useful on systems that have EFI firmware. 1776 In addition, you should use the latest ELILO loader available 1777 at <http://elilo.sourceforge.net> in order to take advantage 1778 of EFI runtime services. However, even with this option, the 1779 resultant kernel should continue to boot on existing non-EFI 1780 platforms. 1781 1782config EFI_STUB 1783 bool "EFI stub support" 1784 depends on EFI && !X86_USE_3DNOW 1785 select RELOCATABLE 1786 ---help--- 1787 This kernel feature allows a bzImage to be loaded directly 1788 by EFI firmware without the use of a bootloader. 1789 1790 See Documentation/efi-stub.txt for more information. 1791 1792config EFI_MIXED 1793 bool "EFI mixed-mode support" 1794 depends on EFI_STUB && X86_64 1795 ---help--- 1796 Enabling this feature allows a 64-bit kernel to be booted 1797 on a 32-bit firmware, provided that your CPU supports 64-bit 1798 mode. 1799 1800 Note that it is not possible to boot a mixed-mode enabled 1801 kernel via the EFI boot stub - a bootloader that supports 1802 the EFI handover protocol must be used. 1803 1804 If unsure, say N. 1805 1806config SECCOMP 1807 def_bool y 1808 prompt "Enable seccomp to safely compute untrusted bytecode" 1809 ---help--- 1810 This kernel feature is useful for number crunching applications 1811 that may need to compute untrusted bytecode during their 1812 execution. By using pipes or other transports made available to 1813 the process as file descriptors supporting the read/write 1814 syscalls, it's possible to isolate those applications in 1815 their own address space using seccomp. Once seccomp is 1816 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1817 and the task is only allowed to execute a few safe syscalls 1818 defined by each seccomp mode. 1819 1820 If unsure, say Y. Only embedded should say N here. 1821 1822source kernel/Kconfig.hz 1823 1824config KEXEC 1825 bool "kexec system call" 1826 select KEXEC_CORE 1827 ---help--- 1828 kexec is a system call that implements the ability to shutdown your 1829 current kernel, and to start another kernel. It is like a reboot 1830 but it is independent of the system firmware. And like a reboot 1831 you can start any kernel with it, not just Linux. 1832 1833 The name comes from the similarity to the exec system call. 1834 1835 It is an ongoing process to be certain the hardware in a machine 1836 is properly shutdown, so do not be surprised if this code does not 1837 initially work for you. As of this writing the exact hardware 1838 interface is strongly in flux, so no good recommendation can be 1839 made. 1840 1841config KEXEC_FILE 1842 bool "kexec file based system call" 1843 select KEXEC_CORE 1844 select BUILD_BIN2C 1845 depends on X86_64 1846 depends on CRYPTO=y 1847 depends on CRYPTO_SHA256=y 1848 ---help--- 1849 This is new version of kexec system call. This system call is 1850 file based and takes file descriptors as system call argument 1851 for kernel and initramfs as opposed to list of segments as 1852 accepted by previous system call. 1853 1854config KEXEC_VERIFY_SIG 1855 bool "Verify kernel signature during kexec_file_load() syscall" 1856 depends on KEXEC_FILE 1857 ---help--- 1858 This option makes kernel signature verification mandatory for 1859 the kexec_file_load() syscall. 1860 1861 In addition to that option, you need to enable signature 1862 verification for the corresponding kernel image type being 1863 loaded in order for this to work. 1864 1865config KEXEC_BZIMAGE_VERIFY_SIG 1866 bool "Enable bzImage signature verification support" 1867 depends on KEXEC_VERIFY_SIG 1868 depends on SIGNED_PE_FILE_VERIFICATION 1869 select SYSTEM_TRUSTED_KEYRING 1870 ---help--- 1871 Enable bzImage signature verification support. 1872 1873config CRASH_DUMP 1874 bool "kernel crash dumps" 1875 depends on X86_64 || (X86_32 && HIGHMEM) 1876 ---help--- 1877 Generate crash dump after being started by kexec. 1878 This should be normally only set in special crash dump kernels 1879 which are loaded in the main kernel with kexec-tools into 1880 a specially reserved region and then later executed after 1881 a crash by kdump/kexec. The crash dump kernel must be compiled 1882 to a memory address not used by the main kernel or BIOS using 1883 PHYSICAL_START, or it must be built as a relocatable image 1884 (CONFIG_RELOCATABLE=y). 1885 For more details see Documentation/kdump/kdump.txt 1886 1887config KEXEC_JUMP 1888 bool "kexec jump" 1889 depends on KEXEC && HIBERNATION 1890 ---help--- 1891 Jump between original kernel and kexeced kernel and invoke 1892 code in physical address mode via KEXEC 1893 1894config PHYSICAL_START 1895 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1896 default "0x1000000" 1897 ---help--- 1898 This gives the physical address where the kernel is loaded. 1899 1900 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1901 bzImage will decompress itself to above physical address and 1902 run from there. Otherwise, bzImage will run from the address where 1903 it has been loaded by the boot loader and will ignore above physical 1904 address. 1905 1906 In normal kdump cases one does not have to set/change this option 1907 as now bzImage can be compiled as a completely relocatable image 1908 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1909 address. This option is mainly useful for the folks who don't want 1910 to use a bzImage for capturing the crash dump and want to use a 1911 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1912 to be specifically compiled to run from a specific memory area 1913 (normally a reserved region) and this option comes handy. 1914 1915 So if you are using bzImage for capturing the crash dump, 1916 leave the value here unchanged to 0x1000000 and set 1917 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1918 for capturing the crash dump change this value to start of 1919 the reserved region. In other words, it can be set based on 1920 the "X" value as specified in the "crashkernel=YM@XM" 1921 command line boot parameter passed to the panic-ed 1922 kernel. Please take a look at Documentation/kdump/kdump.txt 1923 for more details about crash dumps. 1924 1925 Usage of bzImage for capturing the crash dump is recommended as 1926 one does not have to build two kernels. Same kernel can be used 1927 as production kernel and capture kernel. Above option should have 1928 gone away after relocatable bzImage support is introduced. But it 1929 is present because there are users out there who continue to use 1930 vmlinux for dump capture. This option should go away down the 1931 line. 1932 1933 Don't change this unless you know what you are doing. 1934 1935config RELOCATABLE 1936 bool "Build a relocatable kernel" 1937 default y 1938 ---help--- 1939 This builds a kernel image that retains relocation information 1940 so it can be loaded someplace besides the default 1MB. 1941 The relocations tend to make the kernel binary about 10% larger, 1942 but are discarded at runtime. 1943 1944 One use is for the kexec on panic case where the recovery kernel 1945 must live at a different physical address than the primary 1946 kernel. 1947 1948 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1949 it has been loaded at and the compile time physical address 1950 (CONFIG_PHYSICAL_START) is used as the minimum location. 1951 1952config RANDOMIZE_BASE 1953 bool "Randomize the address of the kernel image" 1954 depends on RELOCATABLE 1955 default n 1956 ---help--- 1957 Randomizes the physical and virtual address at which the 1958 kernel image is decompressed, as a security feature that 1959 deters exploit attempts relying on knowledge of the location 1960 of kernel internals. 1961 1962 Entropy is generated using the RDRAND instruction if it is 1963 supported. If RDTSC is supported, it is used as well. If 1964 neither RDRAND nor RDTSC are supported, then randomness is 1965 read from the i8254 timer. 1966 1967 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1968 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1969 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1970 minimum of 2MiB, only 10 bits of entropy is theoretically 1971 possible. At best, due to page table layouts, 64-bit can use 1972 9 bits of entropy and 32-bit uses 8 bits. 1973 1974 If unsure, say N. 1975 1976config RANDOMIZE_BASE_MAX_OFFSET 1977 hex "Maximum kASLR offset allowed" if EXPERT 1978 depends on RANDOMIZE_BASE 1979 range 0x0 0x20000000 if X86_32 1980 default "0x20000000" if X86_32 1981 range 0x0 0x40000000 if X86_64 1982 default "0x40000000" if X86_64 1983 ---help--- 1984 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1985 memory is used to determine the maximal offset in bytes that will 1986 be applied to the kernel when kernel Address Space Layout 1987 Randomization (kASLR) is active. This must be a multiple of 1988 PHYSICAL_ALIGN. 1989 1990 On 32-bit this is limited to 512MiB by page table layouts. The 1991 default is 512MiB. 1992 1993 On 64-bit this is limited by how the kernel fixmap page table is 1994 positioned, so this cannot be larger than 1GiB currently. Without 1995 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1996 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1997 modules area will shrink to compensate, up to the current maximum 1998 1GiB to 1GiB split. The default is 1GiB. 1999 2000 If unsure, leave at the default value. 2001 2002# Relocation on x86 needs some additional build support 2003config X86_NEED_RELOCS 2004 def_bool y 2005 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2006 2007config PHYSICAL_ALIGN 2008 hex "Alignment value to which kernel should be aligned" 2009 default "0x200000" 2010 range 0x2000 0x1000000 if X86_32 2011 range 0x200000 0x1000000 if X86_64 2012 ---help--- 2013 This value puts the alignment restrictions on physical address 2014 where kernel is loaded and run from. Kernel is compiled for an 2015 address which meets above alignment restriction. 2016 2017 If bootloader loads the kernel at a non-aligned address and 2018 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2019 address aligned to above value and run from there. 2020 2021 If bootloader loads the kernel at a non-aligned address and 2022 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2023 load address and decompress itself to the address it has been 2024 compiled for and run from there. The address for which kernel is 2025 compiled already meets above alignment restrictions. Hence the 2026 end result is that kernel runs from a physical address meeting 2027 above alignment restrictions. 2028 2029 On 32-bit this value must be a multiple of 0x2000. On 64-bit 2030 this value must be a multiple of 0x200000. 2031 2032 Don't change this unless you know what you are doing. 2033 2034config HOTPLUG_CPU 2035 def_bool y 2036 depends on SMP 2037 2038config BOOTPARAM_HOTPLUG_CPU0 2039 bool "Set default setting of cpu0_hotpluggable" 2040 default n 2041 depends on HOTPLUG_CPU 2042 ---help--- 2043 Set whether default state of cpu0_hotpluggable is on or off. 2044 2045 Say Y here to enable CPU0 hotplug by default. If this switch 2046 is turned on, there is no need to give cpu0_hotplug kernel 2047 parameter and the CPU0 hotplug feature is enabled by default. 2048 2049 Please note: there are two known CPU0 dependencies if you want 2050 to enable the CPU0 hotplug feature either by this switch or by 2051 cpu0_hotplug kernel parameter. 2052 2053 First, resume from hibernate or suspend always starts from CPU0. 2054 So hibernate and suspend are prevented if CPU0 is offline. 2055 2056 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2057 offline if any interrupt can not migrate out of CPU0. There may 2058 be other CPU0 dependencies. 2059 2060 Please make sure the dependencies are under your control before 2061 you enable this feature. 2062 2063 Say N if you don't want to enable CPU0 hotplug feature by default. 2064 You still can enable the CPU0 hotplug feature at boot by kernel 2065 parameter cpu0_hotplug. 2066 2067config DEBUG_HOTPLUG_CPU0 2068 def_bool n 2069 prompt "Debug CPU0 hotplug" 2070 depends on HOTPLUG_CPU 2071 ---help--- 2072 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2073 soon as possible and boots up userspace with CPU0 offlined. User 2074 can online CPU0 back after boot time. 2075 2076 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2077 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2078 compilation or giving cpu0_hotplug kernel parameter at boot. 2079 2080 If unsure, say N. 2081 2082config COMPAT_VDSO 2083 def_bool n 2084 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2085 depends on X86_32 || IA32_EMULATION 2086 ---help--- 2087 Certain buggy versions of glibc will crash if they are 2088 presented with a 32-bit vDSO that is not mapped at the address 2089 indicated in its segment table. 2090 2091 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2092 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2093 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2094 the only released version with the bug, but OpenSUSE 9 2095 contains a buggy "glibc 2.3.2". 2096 2097 The symptom of the bug is that everything crashes on startup, saying: 2098 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2099 2100 Saying Y here changes the default value of the vdso32 boot 2101 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2102 This works around the glibc bug but hurts performance. 2103 2104 If unsure, say N: if you are compiling your own kernel, you 2105 are unlikely to be using a buggy version of glibc. 2106 2107choice 2108 prompt "vsyscall table for legacy applications" 2109 depends on X86_64 2110 default LEGACY_VSYSCALL_EMULATE 2111 help 2112 Legacy user code that does not know how to find the vDSO expects 2113 to be able to issue three syscalls by calling fixed addresses in 2114 kernel space. Since this location is not randomized with ASLR, 2115 it can be used to assist security vulnerability exploitation. 2116 2117 This setting can be changed at boot time via the kernel command 2118 line parameter vsyscall=[native|emulate|none]. 2119 2120 On a system with recent enough glibc (2.14 or newer) and no 2121 static binaries, you can say None without a performance penalty 2122 to improve security. 2123 2124 If unsure, select "Emulate". 2125 2126 config LEGACY_VSYSCALL_NATIVE 2127 bool "Native" 2128 help 2129 Actual executable code is located in the fixed vsyscall 2130 address mapping, implementing time() efficiently. Since 2131 this makes the mapping executable, it can be used during 2132 security vulnerability exploitation (traditionally as 2133 ROP gadgets). This configuration is not recommended. 2134 2135 config LEGACY_VSYSCALL_EMULATE 2136 bool "Emulate" 2137 help 2138 The kernel traps and emulates calls into the fixed 2139 vsyscall address mapping. This makes the mapping 2140 non-executable, but it still contains known contents, 2141 which could be used in certain rare security vulnerability 2142 exploits. This configuration is recommended when userspace 2143 still uses the vsyscall area. 2144 2145 config LEGACY_VSYSCALL_NONE 2146 bool "None" 2147 help 2148 There will be no vsyscall mapping at all. This will 2149 eliminate any risk of ASLR bypass due to the vsyscall 2150 fixed address mapping. Attempts to use the vsyscalls 2151 will be reported to dmesg, so that either old or 2152 malicious userspace programs can be identified. 2153 2154endchoice 2155 2156config CMDLINE_BOOL 2157 bool "Built-in kernel command line" 2158 ---help--- 2159 Allow for specifying boot arguments to the kernel at 2160 build time. On some systems (e.g. embedded ones), it is 2161 necessary or convenient to provide some or all of the 2162 kernel boot arguments with the kernel itself (that is, 2163 to not rely on the boot loader to provide them.) 2164 2165 To compile command line arguments into the kernel, 2166 set this option to 'Y', then fill in the 2167 boot arguments in CONFIG_CMDLINE. 2168 2169 Systems with fully functional boot loaders (i.e. non-embedded) 2170 should leave this option set to 'N'. 2171 2172config CMDLINE 2173 string "Built-in kernel command string" 2174 depends on CMDLINE_BOOL 2175 default "" 2176 ---help--- 2177 Enter arguments here that should be compiled into the kernel 2178 image and used at boot time. If the boot loader provides a 2179 command line at boot time, it is appended to this string to 2180 form the full kernel command line, when the system boots. 2181 2182 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2183 change this behavior. 2184 2185 In most cases, the command line (whether built-in or provided 2186 by the boot loader) should specify the device for the root 2187 file system. 2188 2189config CMDLINE_OVERRIDE 2190 bool "Built-in command line overrides boot loader arguments" 2191 depends on CMDLINE_BOOL 2192 ---help--- 2193 Set this option to 'Y' to have the kernel ignore the boot loader 2194 command line, and use ONLY the built-in command line. 2195 2196 This is used to work around broken boot loaders. This should 2197 be set to 'N' under normal conditions. 2198 2199config MODIFY_LDT_SYSCALL 2200 bool "Enable the LDT (local descriptor table)" if EXPERT 2201 default y 2202 ---help--- 2203 Linux can allow user programs to install a per-process x86 2204 Local Descriptor Table (LDT) using the modify_ldt(2) system 2205 call. This is required to run 16-bit or segmented code such as 2206 DOSEMU or some Wine programs. It is also used by some very old 2207 threading libraries. 2208 2209 Enabling this feature adds a small amount of overhead to 2210 context switches and increases the low-level kernel attack 2211 surface. Disabling it removes the modify_ldt(2) system call. 2212 2213 Saying 'N' here may make sense for embedded or server kernels. 2214 2215source "kernel/livepatch/Kconfig" 2216 2217endmenu 2218 2219config ARCH_ENABLE_MEMORY_HOTPLUG 2220 def_bool y 2221 depends on X86_64 || (X86_32 && HIGHMEM) 2222 2223config ARCH_ENABLE_MEMORY_HOTREMOVE 2224 def_bool y 2225 depends on MEMORY_HOTPLUG 2226 2227config USE_PERCPU_NUMA_NODE_ID 2228 def_bool y 2229 depends on NUMA 2230 2231config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2232 def_bool y 2233 depends on X86_64 || X86_PAE 2234 2235config ARCH_ENABLE_HUGEPAGE_MIGRATION 2236 def_bool y 2237 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2238 2239menu "Power management and ACPI options" 2240 2241config ARCH_HIBERNATION_HEADER 2242 def_bool y 2243 depends on X86_64 && HIBERNATION 2244 2245source "kernel/power/Kconfig" 2246 2247source "drivers/acpi/Kconfig" 2248 2249source "drivers/sfi/Kconfig" 2250 2251config X86_APM_BOOT 2252 def_bool y 2253 depends on APM 2254 2255menuconfig APM 2256 tristate "APM (Advanced Power Management) BIOS support" 2257 depends on X86_32 && PM_SLEEP 2258 ---help--- 2259 APM is a BIOS specification for saving power using several different 2260 techniques. This is mostly useful for battery powered laptops with 2261 APM compliant BIOSes. If you say Y here, the system time will be 2262 reset after a RESUME operation, the /proc/apm device will provide 2263 battery status information, and user-space programs will receive 2264 notification of APM "events" (e.g. battery status change). 2265 2266 If you select "Y" here, you can disable actual use of the APM 2267 BIOS by passing the "apm=off" option to the kernel at boot time. 2268 2269 Note that the APM support is almost completely disabled for 2270 machines with more than one CPU. 2271 2272 In order to use APM, you will need supporting software. For location 2273 and more information, read <file:Documentation/power/apm-acpi.txt> 2274 and the Battery Powered Linux mini-HOWTO, available from 2275 <http://www.tldp.org/docs.html#howto>. 2276 2277 This driver does not spin down disk drives (see the hdparm(8) 2278 manpage ("man 8 hdparm") for that), and it doesn't turn off 2279 VESA-compliant "green" monitors. 2280 2281 This driver does not support the TI 4000M TravelMate and the ACER 2282 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2283 desktop machines also don't have compliant BIOSes, and this driver 2284 may cause those machines to panic during the boot phase. 2285 2286 Generally, if you don't have a battery in your machine, there isn't 2287 much point in using this driver and you should say N. If you get 2288 random kernel OOPSes or reboots that don't seem to be related to 2289 anything, try disabling/enabling this option (or disabling/enabling 2290 APM in your BIOS). 2291 2292 Some other things you should try when experiencing seemingly random, 2293 "weird" problems: 2294 2295 1) make sure that you have enough swap space and that it is 2296 enabled. 2297 2) pass the "no-hlt" option to the kernel 2298 3) switch on floating point emulation in the kernel and pass 2299 the "no387" option to the kernel 2300 4) pass the "floppy=nodma" option to the kernel 2301 5) pass the "mem=4M" option to the kernel (thereby disabling 2302 all but the first 4 MB of RAM) 2303 6) make sure that the CPU is not over clocked. 2304 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2305 8) disable the cache from your BIOS settings 2306 9) install a fan for the video card or exchange video RAM 2307 10) install a better fan for the CPU 2308 11) exchange RAM chips 2309 12) exchange the motherboard. 2310 2311 To compile this driver as a module, choose M here: the 2312 module will be called apm. 2313 2314if APM 2315 2316config APM_IGNORE_USER_SUSPEND 2317 bool "Ignore USER SUSPEND" 2318 ---help--- 2319 This option will ignore USER SUSPEND requests. On machines with a 2320 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2321 series notebooks, it is necessary to say Y because of a BIOS bug. 2322 2323config APM_DO_ENABLE 2324 bool "Enable PM at boot time" 2325 ---help--- 2326 Enable APM features at boot time. From page 36 of the APM BIOS 2327 specification: "When disabled, the APM BIOS does not automatically 2328 power manage devices, enter the Standby State, enter the Suspend 2329 State, or take power saving steps in response to CPU Idle calls." 2330 This driver will make CPU Idle calls when Linux is idle (unless this 2331 feature is turned off -- see "Do CPU IDLE calls", below). This 2332 should always save battery power, but more complicated APM features 2333 will be dependent on your BIOS implementation. You may need to turn 2334 this option off if your computer hangs at boot time when using APM 2335 support, or if it beeps continuously instead of suspending. Turn 2336 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2337 T400CDT. This is off by default since most machines do fine without 2338 this feature. 2339 2340config APM_CPU_IDLE 2341 depends on CPU_IDLE 2342 bool "Make CPU Idle calls when idle" 2343 ---help--- 2344 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2345 On some machines, this can activate improved power savings, such as 2346 a slowed CPU clock rate, when the machine is idle. These idle calls 2347 are made after the idle loop has run for some length of time (e.g., 2348 333 mS). On some machines, this will cause a hang at boot time or 2349 whenever the CPU becomes idle. (On machines with more than one CPU, 2350 this option does nothing.) 2351 2352config APM_DISPLAY_BLANK 2353 bool "Enable console blanking using APM" 2354 ---help--- 2355 Enable console blanking using the APM. Some laptops can use this to 2356 turn off the LCD backlight when the screen blanker of the Linux 2357 virtual console blanks the screen. Note that this is only used by 2358 the virtual console screen blanker, and won't turn off the backlight 2359 when using the X Window system. This also doesn't have anything to 2360 do with your VESA-compliant power-saving monitor. Further, this 2361 option doesn't work for all laptops -- it might not turn off your 2362 backlight at all, or it might print a lot of errors to the console, 2363 especially if you are using gpm. 2364 2365config APM_ALLOW_INTS 2366 bool "Allow interrupts during APM BIOS calls" 2367 ---help--- 2368 Normally we disable external interrupts while we are making calls to 2369 the APM BIOS as a measure to lessen the effects of a badly behaving 2370 BIOS implementation. The BIOS should reenable interrupts if it 2371 needs to. Unfortunately, some BIOSes do not -- especially those in 2372 many of the newer IBM Thinkpads. If you experience hangs when you 2373 suspend, try setting this to Y. Otherwise, say N. 2374 2375endif # APM 2376 2377source "drivers/cpufreq/Kconfig" 2378 2379source "drivers/cpuidle/Kconfig" 2380 2381source "drivers/idle/Kconfig" 2382 2383endmenu 2384 2385 2386menu "Bus options (PCI etc.)" 2387 2388config PCI 2389 bool "PCI support" 2390 default y 2391 ---help--- 2392 Find out whether you have a PCI motherboard. PCI is the name of a 2393 bus system, i.e. the way the CPU talks to the other stuff inside 2394 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2395 VESA. If you have PCI, say Y, otherwise N. 2396 2397choice 2398 prompt "PCI access mode" 2399 depends on X86_32 && PCI 2400 default PCI_GOANY 2401 ---help--- 2402 On PCI systems, the BIOS can be used to detect the PCI devices and 2403 determine their configuration. However, some old PCI motherboards 2404 have BIOS bugs and may crash if this is done. Also, some embedded 2405 PCI-based systems don't have any BIOS at all. Linux can also try to 2406 detect the PCI hardware directly without using the BIOS. 2407 2408 With this option, you can specify how Linux should detect the 2409 PCI devices. If you choose "BIOS", the BIOS will be used, 2410 if you choose "Direct", the BIOS won't be used, and if you 2411 choose "MMConfig", then PCI Express MMCONFIG will be used. 2412 If you choose "Any", the kernel will try MMCONFIG, then the 2413 direct access method and falls back to the BIOS if that doesn't 2414 work. If unsure, go with the default, which is "Any". 2415 2416config PCI_GOBIOS 2417 bool "BIOS" 2418 2419config PCI_GOMMCONFIG 2420 bool "MMConfig" 2421 2422config PCI_GODIRECT 2423 bool "Direct" 2424 2425config PCI_GOOLPC 2426 bool "OLPC XO-1" 2427 depends on OLPC 2428 2429config PCI_GOANY 2430 bool "Any" 2431 2432endchoice 2433 2434config PCI_BIOS 2435 def_bool y 2436 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2437 2438# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2439config PCI_DIRECT 2440 def_bool y 2441 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2442 2443config PCI_MMCONFIG 2444 def_bool y 2445 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2446 2447config PCI_OLPC 2448 def_bool y 2449 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2450 2451config PCI_XEN 2452 def_bool y 2453 depends on PCI && XEN 2454 select SWIOTLB_XEN 2455 2456config PCI_DOMAINS 2457 def_bool y 2458 depends on PCI 2459 2460config PCI_MMCONFIG 2461 bool "Support mmconfig PCI config space access" 2462 depends on X86_64 && PCI && ACPI 2463 2464config PCI_CNB20LE_QUIRK 2465 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2466 depends on PCI 2467 help 2468 Read the PCI windows out of the CNB20LE host bridge. This allows 2469 PCI hotplug to work on systems with the CNB20LE chipset which do 2470 not have ACPI. 2471 2472 There's no public spec for this chipset, and this functionality 2473 is known to be incomplete. 2474 2475 You should say N unless you know you need this. 2476 2477source "drivers/pci/pcie/Kconfig" 2478 2479source "drivers/pci/Kconfig" 2480 2481# x86_64 have no ISA slots, but can have ISA-style DMA. 2482config ISA_DMA_API 2483 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2484 default y 2485 help 2486 Enables ISA-style DMA support for devices requiring such controllers. 2487 If unsure, say Y. 2488 2489if X86_32 2490 2491config ISA 2492 bool "ISA support" 2493 ---help--- 2494 Find out whether you have ISA slots on your motherboard. ISA is the 2495 name of a bus system, i.e. the way the CPU talks to the other stuff 2496 inside your box. Other bus systems are PCI, EISA, MicroChannel 2497 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2498 newer boards don't support it. If you have ISA, say Y, otherwise N. 2499 2500config EISA 2501 bool "EISA support" 2502 depends on ISA 2503 ---help--- 2504 The Extended Industry Standard Architecture (EISA) bus was 2505 developed as an open alternative to the IBM MicroChannel bus. 2506 2507 The EISA bus provided some of the features of the IBM MicroChannel 2508 bus while maintaining backward compatibility with cards made for 2509 the older ISA bus. The EISA bus saw limited use between 1988 and 2510 1995 when it was made obsolete by the PCI bus. 2511 2512 Say Y here if you are building a kernel for an EISA-based machine. 2513 2514 Otherwise, say N. 2515 2516source "drivers/eisa/Kconfig" 2517 2518config SCx200 2519 tristate "NatSemi SCx200 support" 2520 ---help--- 2521 This provides basic support for National Semiconductor's 2522 (now AMD's) Geode processors. The driver probes for the 2523 PCI-IDs of several on-chip devices, so its a good dependency 2524 for other scx200_* drivers. 2525 2526 If compiled as a module, the driver is named scx200. 2527 2528config SCx200HR_TIMER 2529 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2530 depends on SCx200 2531 default y 2532 ---help--- 2533 This driver provides a clocksource built upon the on-chip 2534 27MHz high-resolution timer. Its also a workaround for 2535 NSC Geode SC-1100's buggy TSC, which loses time when the 2536 processor goes idle (as is done by the scheduler). The 2537 other workaround is idle=poll boot option. 2538 2539config OLPC 2540 bool "One Laptop Per Child support" 2541 depends on !X86_PAE 2542 select GPIOLIB 2543 select OF 2544 select OF_PROMTREE 2545 select IRQ_DOMAIN 2546 ---help--- 2547 Add support for detecting the unique features of the OLPC 2548 XO hardware. 2549 2550config OLPC_XO1_PM 2551 bool "OLPC XO-1 Power Management" 2552 depends on OLPC && MFD_CS5535=y && PM_SLEEP 2553 ---help--- 2554 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2555 2556config OLPC_XO1_RTC 2557 bool "OLPC XO-1 Real Time Clock" 2558 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2559 ---help--- 2560 Add support for the XO-1 real time clock, which can be used as a 2561 programmable wakeup source. 2562 2563config OLPC_XO1_SCI 2564 bool "OLPC XO-1 SCI extras" 2565 depends on OLPC && OLPC_XO1_PM 2566 depends on INPUT=y 2567 select POWER_SUPPLY 2568 select GPIO_CS5535 2569 select MFD_CORE 2570 ---help--- 2571 Add support for SCI-based features of the OLPC XO-1 laptop: 2572 - EC-driven system wakeups 2573 - Power button 2574 - Ebook switch 2575 - Lid switch 2576 - AC adapter status updates 2577 - Battery status updates 2578 2579config OLPC_XO15_SCI 2580 bool "OLPC XO-1.5 SCI extras" 2581 depends on OLPC && ACPI 2582 select POWER_SUPPLY 2583 ---help--- 2584 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2585 - EC-driven system wakeups 2586 - AC adapter status updates 2587 - Battery status updates 2588 2589config ALIX 2590 bool "PCEngines ALIX System Support (LED setup)" 2591 select GPIOLIB 2592 ---help--- 2593 This option enables system support for the PCEngines ALIX. 2594 At present this just sets up LEDs for GPIO control on 2595 ALIX2/3/6 boards. However, other system specific setup should 2596 get added here. 2597 2598 Note: You must still enable the drivers for GPIO and LED support 2599 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2600 2601 Note: You have to set alix.force=1 for boards with Award BIOS. 2602 2603config NET5501 2604 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2605 select GPIOLIB 2606 ---help--- 2607 This option enables system support for the Soekris Engineering net5501. 2608 2609config GEOS 2610 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2611 select GPIOLIB 2612 depends on DMI 2613 ---help--- 2614 This option enables system support for the Traverse Technologies GEOS. 2615 2616config TS5500 2617 bool "Technologic Systems TS-5500 platform support" 2618 depends on MELAN 2619 select CHECK_SIGNATURE 2620 select NEW_LEDS 2621 select LEDS_CLASS 2622 ---help--- 2623 This option enables system support for the Technologic Systems TS-5500. 2624 2625endif # X86_32 2626 2627config AMD_NB 2628 def_bool y 2629 depends on CPU_SUP_AMD && PCI 2630 2631source "drivers/pcmcia/Kconfig" 2632 2633source "drivers/pci/hotplug/Kconfig" 2634 2635config RAPIDIO 2636 tristate "RapidIO support" 2637 depends on PCI 2638 default n 2639 help 2640 If enabled this option will include drivers and the core 2641 infrastructure code to support RapidIO interconnect devices. 2642 2643source "drivers/rapidio/Kconfig" 2644 2645config X86_SYSFB 2646 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2647 help 2648 Firmwares often provide initial graphics framebuffers so the BIOS, 2649 bootloader or kernel can show basic video-output during boot for 2650 user-guidance and debugging. Historically, x86 used the VESA BIOS 2651 Extensions and EFI-framebuffers for this, which are mostly limited 2652 to x86. 2653 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2654 framebuffers so the new generic system-framebuffer drivers can be 2655 used on x86. If the framebuffer is not compatible with the generic 2656 modes, it is adverticed as fallback platform framebuffer so legacy 2657 drivers like efifb, vesafb and uvesafb can pick it up. 2658 If this option is not selected, all system framebuffers are always 2659 marked as fallback platform framebuffers as usual. 2660 2661 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2662 not be able to pick up generic system framebuffers if this option 2663 is selected. You are highly encouraged to enable simplefb as 2664 replacement if you select this option. simplefb can correctly deal 2665 with generic system framebuffers. But you should still keep vesafb 2666 and others enabled as fallback if a system framebuffer is 2667 incompatible with simplefb. 2668 2669 If unsure, say Y. 2670 2671endmenu 2672 2673 2674menu "Executable file formats / Emulations" 2675 2676source "fs/Kconfig.binfmt" 2677 2678config IA32_EMULATION 2679 bool "IA32 Emulation" 2680 depends on X86_64 2681 select BINFMT_ELF 2682 select COMPAT_BINFMT_ELF 2683 select ARCH_WANT_OLD_COMPAT_IPC 2684 ---help--- 2685 Include code to run legacy 32-bit programs under a 2686 64-bit kernel. You should likely turn this on, unless you're 2687 100% sure that you don't have any 32-bit programs left. 2688 2689config IA32_AOUT 2690 tristate "IA32 a.out support" 2691 depends on IA32_EMULATION 2692 ---help--- 2693 Support old a.out binaries in the 32bit emulation. 2694 2695config X86_X32 2696 bool "x32 ABI for 64-bit mode" 2697 depends on X86_64 2698 ---help--- 2699 Include code to run binaries for the x32 native 32-bit ABI 2700 for 64-bit processors. An x32 process gets access to the 2701 full 64-bit register file and wide data path while leaving 2702 pointers at 32 bits for smaller memory footprint. 2703 2704 You will need a recent binutils (2.22 or later) with 2705 elf32_x86_64 support enabled to compile a kernel with this 2706 option set. 2707 2708config COMPAT 2709 def_bool y 2710 depends on IA32_EMULATION || X86_X32 2711 2712if COMPAT 2713config COMPAT_FOR_U64_ALIGNMENT 2714 def_bool y 2715 2716config SYSVIPC_COMPAT 2717 def_bool y 2718 depends on SYSVIPC 2719endif 2720 2721endmenu 2722 2723 2724config HAVE_ATOMIC_IOMAP 2725 def_bool y 2726 depends on X86_32 2727 2728config X86_DEV_DMA_OPS 2729 bool 2730 depends on X86_64 || STA2X11 2731 2732config X86_DMA_REMAP 2733 bool 2734 depends on STA2X11 2735 2736config PMC_ATOM 2737 def_bool y 2738 depends on PCI 2739 2740source "net/Kconfig" 2741 2742source "drivers/Kconfig" 2743 2744source "drivers/firmware/Kconfig" 2745 2746source "fs/Kconfig" 2747 2748source "arch/x86/Kconfig.debug" 2749 2750source "security/Kconfig" 2751 2752source "crypto/Kconfig" 2753 2754source "arch/x86/kvm/Kconfig" 2755 2756source "lib/Kconfig" 2757