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_ACPI_TABLE_UPGRADE if ACPI 26 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 27 select ARCH_HAS_DEVMEM_IS_ALLOWED 28 select ARCH_HAS_ELF_RANDOMIZE 29 select ARCH_HAS_FAST_MULTIPLIER 30 select ARCH_HAS_GCOV_PROFILE_ALL 31 select ARCH_HAS_KCOV if X86_64 32 select ARCH_HAS_PMEM_API if X86_64 33 select ARCH_HAS_MMIO_FLUSH 34 select ARCH_HAS_SG_CHAIN 35 select ARCH_HAS_UBSAN_SANITIZE_ALL 36 select ARCH_HAVE_NMI_SAFE_CMPXCHG 37 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 38 select ARCH_MIGHT_HAVE_PC_PARPORT 39 select ARCH_MIGHT_HAVE_PC_SERIO 40 select ARCH_SUPPORTS_ATOMIC_RMW 41 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 42 select ARCH_SUPPORTS_INT128 if X86_64 43 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 44 select ARCH_USE_BUILTIN_BSWAP 45 select ARCH_USE_CMPXCHG_LOCKREF if X86_64 46 select ARCH_USE_QUEUED_RWLOCKS 47 select ARCH_USE_QUEUED_SPINLOCKS 48 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 49 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 50 select ARCH_WANT_FRAME_POINTERS 51 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 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_EARLY_IOREMAP 68 select GENERIC_FIND_FIRST_BIT 69 select GENERIC_IOMAP 70 select GENERIC_IRQ_PROBE 71 select GENERIC_IRQ_SHOW 72 select GENERIC_PENDING_IRQ if SMP 73 select GENERIC_SMP_IDLE_THREAD 74 select GENERIC_STRNCPY_FROM_USER 75 select GENERIC_STRNLEN_USER 76 select GENERIC_TIME_VSYSCALL 77 select HAVE_ACPI_APEI if ACPI 78 select HAVE_ACPI_APEI_NMI if ACPI 79 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 80 select HAVE_AOUT if X86_32 81 select HAVE_ARCH_AUDITSYSCALL 82 select HAVE_ARCH_HARDENED_USERCOPY 83 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 84 select HAVE_ARCH_JUMP_LABEL 85 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 86 select HAVE_ARCH_KGDB 87 select HAVE_ARCH_KMEMCHECK 88 select HAVE_ARCH_MMAP_RND_BITS if MMU 89 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 90 select HAVE_ARCH_SECCOMP_FILTER 91 select HAVE_ARCH_SOFT_DIRTY if X86_64 92 select HAVE_ARCH_TRACEHOOK 93 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 94 select HAVE_ARCH_WITHIN_STACK_FRAMES 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_CONTIGUOUS 106 select HAVE_DYNAMIC_FTRACE 107 select HAVE_DYNAMIC_FTRACE_WITH_REGS 108 select HAVE_EFFICIENT_UNALIGNED_ACCESS 109 select HAVE_EXIT_THREAD 110 select HAVE_FENTRY if X86_64 111 select HAVE_FTRACE_MCOUNT_RECORD 112 select HAVE_FUNCTION_GRAPH_FP_TEST 113 select HAVE_FUNCTION_GRAPH_TRACER 114 select HAVE_FUNCTION_TRACER 115 select HAVE_GCC_PLUGINS 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_NMI 137 select HAVE_OPROFILE 138 select HAVE_OPTPROBES 139 select HAVE_PCSPKR_PLATFORM 140 select HAVE_PERF_EVENTS 141 select HAVE_PERF_EVENTS_NMI 142 select HAVE_PERF_REGS 143 select HAVE_PERF_USER_STACK_DUMP 144 select HAVE_REGS_AND_STACK_ACCESS_API 145 select HAVE_SYSCALL_TRACEPOINTS 146 select HAVE_UID16 if X86_32 || IA32_EMULATION 147 select HAVE_UNSTABLE_SCHED_CLOCK 148 select HAVE_USER_RETURN_NOTIFIER 149 select IRQ_FORCED_THREADING 150 select MODULES_USE_ELF_RELA if X86_64 151 select MODULES_USE_ELF_REL if X86_32 152 select OLD_SIGACTION if X86_32 153 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 154 select PERF_EVENTS 155 select RTC_LIB 156 select RTC_MC146818_LIB 157 select SPARSE_IRQ 158 select SRCU 159 select SYSCTL_EXCEPTION_TRACE 160 select USER_STACKTRACE_SUPPORT 161 select VIRT_TO_BUS 162 select X86_DEV_DMA_OPS if X86_64 163 select X86_FEATURE_NAMES if PROC_FS 164 select HAVE_STACK_VALIDATION if X86_64 165 select ARCH_USES_HIGH_VMA_FLAGS if X86_INTEL_MEMORY_PROTECTION_KEYS 166 select ARCH_HAS_PKEYS if X86_INTEL_MEMORY_PROTECTION_KEYS 167 168config INSTRUCTION_DECODER 169 def_bool y 170 depends on KPROBES || PERF_EVENTS || UPROBES 171 172config OUTPUT_FORMAT 173 string 174 default "elf32-i386" if X86_32 175 default "elf64-x86-64" if X86_64 176 177config ARCH_DEFCONFIG 178 string 179 default "arch/x86/configs/i386_defconfig" if X86_32 180 default "arch/x86/configs/x86_64_defconfig" if X86_64 181 182config LOCKDEP_SUPPORT 183 def_bool y 184 185config STACKTRACE_SUPPORT 186 def_bool y 187 188config MMU 189 def_bool y 190 191config ARCH_MMAP_RND_BITS_MIN 192 default 28 if 64BIT 193 default 8 194 195config ARCH_MMAP_RND_BITS_MAX 196 default 32 if 64BIT 197 default 16 198 199config ARCH_MMAP_RND_COMPAT_BITS_MIN 200 default 8 201 202config ARCH_MMAP_RND_COMPAT_BITS_MAX 203 default 16 204 205config SBUS 206 bool 207 208config NEED_DMA_MAP_STATE 209 def_bool y 210 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 211 212config NEED_SG_DMA_LENGTH 213 def_bool y 214 215config GENERIC_ISA_DMA 216 def_bool y 217 depends on ISA_DMA_API 218 219config GENERIC_BUG 220 def_bool y 221 depends on BUG 222 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 223 224config GENERIC_BUG_RELATIVE_POINTERS 225 bool 226 227config GENERIC_HWEIGHT 228 def_bool y 229 230config ARCH_MAY_HAVE_PC_FDC 231 def_bool y 232 depends on ISA_DMA_API 233 234config RWSEM_XCHGADD_ALGORITHM 235 def_bool y 236 237config GENERIC_CALIBRATE_DELAY 238 def_bool y 239 240config ARCH_HAS_CPU_RELAX 241 def_bool y 242 243config ARCH_HAS_CACHE_LINE_SIZE 244 def_bool y 245 246config HAVE_SETUP_PER_CPU_AREA 247 def_bool y 248 249config NEED_PER_CPU_EMBED_FIRST_CHUNK 250 def_bool y 251 252config NEED_PER_CPU_PAGE_FIRST_CHUNK 253 def_bool y 254 255config ARCH_HIBERNATION_POSSIBLE 256 def_bool y 257 258config ARCH_SUSPEND_POSSIBLE 259 def_bool y 260 261config ARCH_WANT_HUGE_PMD_SHARE 262 def_bool y 263 264config ARCH_WANT_GENERAL_HUGETLB 265 def_bool y 266 267config ZONE_DMA32 268 def_bool y if X86_64 269 270config AUDIT_ARCH 271 def_bool y if X86_64 272 273config ARCH_SUPPORTS_OPTIMIZED_INLINING 274 def_bool y 275 276config ARCH_SUPPORTS_DEBUG_PAGEALLOC 277 def_bool y 278 279config KASAN_SHADOW_OFFSET 280 hex 281 depends on KASAN 282 default 0xdffffc0000000000 283 284config HAVE_INTEL_TXT 285 def_bool y 286 depends on INTEL_IOMMU && ACPI 287 288config X86_32_SMP 289 def_bool y 290 depends on X86_32 && SMP 291 292config X86_64_SMP 293 def_bool y 294 depends on X86_64 && SMP 295 296config X86_32_LAZY_GS 297 def_bool y 298 depends on X86_32 && !CC_STACKPROTECTOR 299 300config ARCH_SUPPORTS_UPROBES 301 def_bool y 302 303config FIX_EARLYCON_MEM 304 def_bool y 305 306config DEBUG_RODATA 307 def_bool y 308 309config PGTABLE_LEVELS 310 int 311 default 4 if X86_64 312 default 3 if X86_PAE 313 default 2 314 315source "init/Kconfig" 316source "kernel/Kconfig.freezer" 317 318menu "Processor type and features" 319 320config ZONE_DMA 321 bool "DMA memory allocation support" if EXPERT 322 default y 323 help 324 DMA memory allocation support allows devices with less than 32-bit 325 addressing to allocate within the first 16MB of address space. 326 Disable if no such devices will be used. 327 328 If unsure, say Y. 329 330config SMP 331 bool "Symmetric multi-processing support" 332 ---help--- 333 This enables support for systems with more than one CPU. If you have 334 a system with only one CPU, say N. If you have a system with more 335 than one CPU, say Y. 336 337 If you say N here, the kernel will run on uni- and multiprocessor 338 machines, but will use only one CPU of a multiprocessor machine. If 339 you say Y here, the kernel will run on many, but not all, 340 uniprocessor machines. On a uniprocessor machine, the kernel 341 will run faster if you say N here. 342 343 Note that if you say Y here and choose architecture "586" or 344 "Pentium" under "Processor family", the kernel will not work on 486 345 architectures. Similarly, multiprocessor kernels for the "PPro" 346 architecture may not work on all Pentium based boards. 347 348 People using multiprocessor machines who say Y here should also say 349 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 350 Management" code will be disabled if you say Y here. 351 352 See also <file:Documentation/x86/i386/IO-APIC.txt>, 353 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 354 <http://www.tldp.org/docs.html#howto>. 355 356 If you don't know what to do here, say N. 357 358config X86_FEATURE_NAMES 359 bool "Processor feature human-readable names" if EMBEDDED 360 default y 361 ---help--- 362 This option compiles in a table of x86 feature bits and corresponding 363 names. This is required to support /proc/cpuinfo and a few kernel 364 messages. You can disable this to save space, at the expense of 365 making those few kernel messages show numeric feature bits instead. 366 367 If in doubt, say Y. 368 369config X86_FAST_FEATURE_TESTS 370 bool "Fast CPU feature tests" if EMBEDDED 371 default y 372 ---help--- 373 Some fast-paths in the kernel depend on the capabilities of the CPU. 374 Say Y here for the kernel to patch in the appropriate code at runtime 375 based on the capabilities of the CPU. The infrastructure for patching 376 code at runtime takes up some additional space; space-constrained 377 embedded systems may wish to say N here to produce smaller, slightly 378 slower code. 379 380config X86_X2APIC 381 bool "Support x2apic" 382 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 383 ---help--- 384 This enables x2apic support on CPUs that have this feature. 385 386 This allows 32-bit apic IDs (so it can support very large systems), 387 and accesses the local apic via MSRs not via mmio. 388 389 If you don't know what to do here, say N. 390 391config X86_MPPARSE 392 bool "Enable MPS table" if ACPI || SFI 393 default y 394 depends on X86_LOCAL_APIC 395 ---help--- 396 For old smp systems that do not have proper acpi support. Newer systems 397 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 398 399config X86_BIGSMP 400 bool "Support for big SMP systems with more than 8 CPUs" 401 depends on X86_32 && SMP 402 ---help--- 403 This option is needed for the systems that have more than 8 CPUs 404 405config GOLDFISH 406 def_bool y 407 depends on X86_GOLDFISH 408 409if X86_32 410config X86_EXTENDED_PLATFORM 411 bool "Support for extended (non-PC) x86 platforms" 412 default y 413 ---help--- 414 If you disable this option then the kernel will only support 415 standard PC platforms. (which covers the vast majority of 416 systems out there.) 417 418 If you enable this option then you'll be able to select support 419 for the following (non-PC) 32 bit x86 platforms: 420 Goldfish (Android emulator) 421 AMD Elan 422 RDC R-321x SoC 423 SGI 320/540 (Visual Workstation) 424 STA2X11-based (e.g. Northville) 425 Moorestown MID devices 426 427 If you have one of these systems, or if you want to build a 428 generic distribution kernel, say Y here - otherwise say N. 429endif 430 431if X86_64 432config X86_EXTENDED_PLATFORM 433 bool "Support for extended (non-PC) x86 platforms" 434 default y 435 ---help--- 436 If you disable this option then the kernel will only support 437 standard PC platforms. (which covers the vast majority of 438 systems out there.) 439 440 If you enable this option then you'll be able to select support 441 for the following (non-PC) 64 bit x86 platforms: 442 Numascale NumaChip 443 ScaleMP vSMP 444 SGI Ultraviolet 445 446 If you have one of these systems, or if you want to build a 447 generic distribution kernel, say Y here - otherwise say N. 448endif 449# This is an alphabetically sorted list of 64 bit extended platforms 450# Please maintain the alphabetic order if and when there are additions 451config X86_NUMACHIP 452 bool "Numascale NumaChip" 453 depends on X86_64 454 depends on X86_EXTENDED_PLATFORM 455 depends on NUMA 456 depends on SMP 457 depends on X86_X2APIC 458 depends on PCI_MMCONFIG 459 ---help--- 460 Adds support for Numascale NumaChip large-SMP systems. Needed to 461 enable more than ~168 cores. 462 If you don't have one of these, you should say N here. 463 464config X86_VSMP 465 bool "ScaleMP vSMP" 466 select HYPERVISOR_GUEST 467 select PARAVIRT 468 depends on X86_64 && PCI 469 depends on X86_EXTENDED_PLATFORM 470 depends on SMP 471 ---help--- 472 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 473 supposed to run on these EM64T-based machines. Only choose this option 474 if you have one of these machines. 475 476config X86_UV 477 bool "SGI Ultraviolet" 478 depends on X86_64 479 depends on X86_EXTENDED_PLATFORM 480 depends on NUMA 481 depends on EFI 482 depends on X86_X2APIC 483 depends on PCI 484 ---help--- 485 This option is needed in order to support SGI Ultraviolet systems. 486 If you don't have one of these, you should say N here. 487 488# Following is an alphabetically sorted list of 32 bit extended platforms 489# Please maintain the alphabetic order if and when there are additions 490 491config X86_GOLDFISH 492 bool "Goldfish (Virtual Platform)" 493 depends on X86_EXTENDED_PLATFORM 494 ---help--- 495 Enable support for the Goldfish virtual platform used primarily 496 for Android development. Unless you are building for the Android 497 Goldfish emulator say N here. 498 499config X86_INTEL_CE 500 bool "CE4100 TV platform" 501 depends on PCI 502 depends on PCI_GODIRECT 503 depends on X86_IO_APIC 504 depends on X86_32 505 depends on X86_EXTENDED_PLATFORM 506 select X86_REBOOTFIXUPS 507 select OF 508 select OF_EARLY_FLATTREE 509 ---help--- 510 Select for the Intel CE media processor (CE4100) SOC. 511 This option compiles in support for the CE4100 SOC for settop 512 boxes and media devices. 513 514config X86_INTEL_MID 515 bool "Intel MID platform support" 516 depends on X86_EXTENDED_PLATFORM 517 depends on X86_PLATFORM_DEVICES 518 depends on PCI 519 depends on X86_64 || (PCI_GOANY && X86_32) 520 depends on X86_IO_APIC 521 select SFI 522 select I2C 523 select DW_APB_TIMER 524 select APB_TIMER 525 select INTEL_SCU_IPC 526 select MFD_INTEL_MSIC 527 ---help--- 528 Select to build a kernel capable of supporting Intel MID (Mobile 529 Internet Device) platform systems which do not have the PCI legacy 530 interfaces. If you are building for a PC class system say N here. 531 532 Intel MID platforms are based on an Intel processor and chipset which 533 consume less power than most of the x86 derivatives. 534 535config X86_INTEL_QUARK 536 bool "Intel Quark platform support" 537 depends on X86_32 538 depends on X86_EXTENDED_PLATFORM 539 depends on X86_PLATFORM_DEVICES 540 depends on X86_TSC 541 depends on PCI 542 depends on PCI_GOANY 543 depends on X86_IO_APIC 544 select IOSF_MBI 545 select INTEL_IMR 546 select COMMON_CLK 547 ---help--- 548 Select to include support for Quark X1000 SoC. 549 Say Y here if you have a Quark based system such as the Arduino 550 compatible Intel Galileo. 551 552config X86_INTEL_LPSS 553 bool "Intel Low Power Subsystem Support" 554 depends on X86 && ACPI 555 select COMMON_CLK 556 select PINCTRL 557 select IOSF_MBI 558 ---help--- 559 Select to build support for Intel Low Power Subsystem such as 560 found on Intel Lynxpoint PCH. Selecting this option enables 561 things like clock tree (common clock framework) and pincontrol 562 which are needed by the LPSS peripheral drivers. 563 564config X86_AMD_PLATFORM_DEVICE 565 bool "AMD ACPI2Platform devices support" 566 depends on ACPI 567 select COMMON_CLK 568 select PINCTRL 569 ---help--- 570 Select to interpret AMD specific ACPI device to platform device 571 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 572 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 573 implemented under PINCTRL subsystem. 574 575config IOSF_MBI 576 tristate "Intel SoC IOSF Sideband support for SoC platforms" 577 depends on PCI 578 ---help--- 579 This option enables sideband register access support for Intel SoC 580 platforms. On these platforms the IOSF sideband is used in lieu of 581 MSR's for some register accesses, mostly but not limited to thermal 582 and power. Drivers may query the availability of this device to 583 determine if they need the sideband in order to work on these 584 platforms. The sideband is available on the following SoC products. 585 This list is not meant to be exclusive. 586 - BayTrail 587 - Braswell 588 - Quark 589 590 You should say Y if you are running a kernel on one of these SoC's. 591 592config IOSF_MBI_DEBUG 593 bool "Enable IOSF sideband access through debugfs" 594 depends on IOSF_MBI && DEBUG_FS 595 ---help--- 596 Select this option to expose the IOSF sideband access registers (MCR, 597 MDR, MCRX) through debugfs to write and read register information from 598 different units on the SoC. This is most useful for obtaining device 599 state information for debug and analysis. As this is a general access 600 mechanism, users of this option would have specific knowledge of the 601 device they want to access. 602 603 If you don't require the option or are in doubt, say N. 604 605config X86_RDC321X 606 bool "RDC R-321x SoC" 607 depends on X86_32 608 depends on X86_EXTENDED_PLATFORM 609 select M486 610 select X86_REBOOTFIXUPS 611 ---help--- 612 This option is needed for RDC R-321x system-on-chip, also known 613 as R-8610-(G). 614 If you don't have one of these chips, you should say N here. 615 616config X86_32_NON_STANDARD 617 bool "Support non-standard 32-bit SMP architectures" 618 depends on X86_32 && SMP 619 depends on X86_EXTENDED_PLATFORM 620 ---help--- 621 This option compiles in the bigsmp and STA2X11 default 622 subarchitectures. It is intended for a generic binary 623 kernel. If you select them all, kernel will probe it one by 624 one and will fallback to default. 625 626# Alphabetically sorted list of Non standard 32 bit platforms 627 628config X86_SUPPORTS_MEMORY_FAILURE 629 def_bool y 630 # MCE code calls memory_failure(): 631 depends on X86_MCE 632 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 633 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 634 depends on X86_64 || !SPARSEMEM 635 select ARCH_SUPPORTS_MEMORY_FAILURE 636 637config STA2X11 638 bool "STA2X11 Companion Chip Support" 639 depends on X86_32_NON_STANDARD && PCI 640 select X86_DEV_DMA_OPS 641 select X86_DMA_REMAP 642 select SWIOTLB 643 select MFD_STA2X11 644 select GPIOLIB 645 default n 646 ---help--- 647 This adds support for boards based on the STA2X11 IO-Hub, 648 a.k.a. "ConneXt". The chip is used in place of the standard 649 PC chipset, so all "standard" peripherals are missing. If this 650 option is selected the kernel will still be able to boot on 651 standard PC machines. 652 653config X86_32_IRIS 654 tristate "Eurobraille/Iris poweroff module" 655 depends on X86_32 656 ---help--- 657 The Iris machines from EuroBraille do not have APM or ACPI support 658 to shut themselves down properly. A special I/O sequence is 659 needed to do so, which is what this module does at 660 kernel shutdown. 661 662 This is only for Iris machines from EuroBraille. 663 664 If unused, say N. 665 666config SCHED_OMIT_FRAME_POINTER 667 def_bool y 668 prompt "Single-depth WCHAN output" 669 depends on X86 670 ---help--- 671 Calculate simpler /proc/<PID>/wchan values. If this option 672 is disabled then wchan values will recurse back to the 673 caller function. This provides more accurate wchan values, 674 at the expense of slightly more scheduling overhead. 675 676 If in doubt, say "Y". 677 678menuconfig HYPERVISOR_GUEST 679 bool "Linux guest support" 680 ---help--- 681 Say Y here to enable options for running Linux under various hyper- 682 visors. This option enables basic hypervisor detection and platform 683 setup. 684 685 If you say N, all options in this submenu will be skipped and 686 disabled, and Linux guest support won't be built in. 687 688if HYPERVISOR_GUEST 689 690config PARAVIRT 691 bool "Enable paravirtualization code" 692 ---help--- 693 This changes the kernel so it can modify itself when it is run 694 under a hypervisor, potentially improving performance significantly 695 over full virtualization. However, when run without a hypervisor 696 the kernel is theoretically slower and slightly larger. 697 698config PARAVIRT_DEBUG 699 bool "paravirt-ops debugging" 700 depends on PARAVIRT && DEBUG_KERNEL 701 ---help--- 702 Enable to debug paravirt_ops internals. Specifically, BUG if 703 a paravirt_op is missing when it is called. 704 705config PARAVIRT_SPINLOCKS 706 bool "Paravirtualization layer for spinlocks" 707 depends on PARAVIRT && SMP 708 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS 709 ---help--- 710 Paravirtualized spinlocks allow a pvops backend to replace the 711 spinlock implementation with something virtualization-friendly 712 (for example, block the virtual CPU rather than spinning). 713 714 It has a minimal impact on native kernels and gives a nice performance 715 benefit on paravirtualized KVM / Xen kernels. 716 717 If you are unsure how to answer this question, answer Y. 718 719config QUEUED_LOCK_STAT 720 bool "Paravirt queued spinlock statistics" 721 depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS 722 ---help--- 723 Enable the collection of statistical data on the slowpath 724 behavior of paravirtualized queued spinlocks and report 725 them on debugfs. 726 727source "arch/x86/xen/Kconfig" 728 729config KVM_GUEST 730 bool "KVM Guest support (including kvmclock)" 731 depends on PARAVIRT 732 select PARAVIRT_CLOCK 733 default y 734 ---help--- 735 This option enables various optimizations for running under the KVM 736 hypervisor. It includes a paravirtualized clock, so that instead 737 of relying on a PIT (or probably other) emulation by the 738 underlying device model, the host provides the guest with 739 timing infrastructure such as time of day, and system time 740 741config KVM_DEBUG_FS 742 bool "Enable debug information for KVM Guests in debugfs" 743 depends on KVM_GUEST && DEBUG_FS 744 default n 745 ---help--- 746 This option enables collection of various statistics for KVM guest. 747 Statistics are displayed in debugfs filesystem. Enabling this option 748 may incur significant overhead. 749 750source "arch/x86/lguest/Kconfig" 751 752config PARAVIRT_TIME_ACCOUNTING 753 bool "Paravirtual steal time accounting" 754 depends on PARAVIRT 755 default n 756 ---help--- 757 Select this option to enable fine granularity task steal time 758 accounting. Time spent executing other tasks in parallel with 759 the current vCPU is discounted from the vCPU power. To account for 760 that, there can be a small performance impact. 761 762 If in doubt, say N here. 763 764config PARAVIRT_CLOCK 765 bool 766 767endif #HYPERVISOR_GUEST 768 769config NO_BOOTMEM 770 def_bool y 771 772source "arch/x86/Kconfig.cpu" 773 774config HPET_TIMER 775 def_bool X86_64 776 prompt "HPET Timer Support" if X86_32 777 ---help--- 778 Use the IA-PC HPET (High Precision Event Timer) to manage 779 time in preference to the PIT and RTC, if a HPET is 780 present. 781 HPET is the next generation timer replacing legacy 8254s. 782 The HPET provides a stable time base on SMP 783 systems, unlike the TSC, but it is more expensive to access, 784 as it is off-chip. The interface used is documented 785 in the HPET spec, revision 1. 786 787 You can safely choose Y here. However, HPET will only be 788 activated if the platform and the BIOS support this feature. 789 Otherwise the 8254 will be used for timing services. 790 791 Choose N to continue using the legacy 8254 timer. 792 793config HPET_EMULATE_RTC 794 def_bool y 795 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 796 797config APB_TIMER 798 def_bool y if X86_INTEL_MID 799 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 800 select DW_APB_TIMER 801 depends on X86_INTEL_MID && SFI 802 help 803 APB timer is the replacement for 8254, HPET on X86 MID platforms. 804 The APBT provides a stable time base on SMP 805 systems, unlike the TSC, but it is more expensive to access, 806 as it is off-chip. APB timers are always running regardless of CPU 807 C states, they are used as per CPU clockevent device when possible. 808 809# Mark as expert because too many people got it wrong. 810# The code disables itself when not needed. 811config DMI 812 default y 813 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 814 bool "Enable DMI scanning" if EXPERT 815 ---help--- 816 Enabled scanning of DMI to identify machine quirks. Say Y 817 here unless you have verified that your setup is not 818 affected by entries in the DMI blacklist. Required by PNP 819 BIOS code. 820 821config GART_IOMMU 822 bool "Old AMD GART IOMMU support" 823 select SWIOTLB 824 depends on X86_64 && PCI && AMD_NB 825 ---help--- 826 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 827 GART based hardware IOMMUs. 828 829 The GART supports full DMA access for devices with 32-bit access 830 limitations, on systems with more than 3 GB. This is usually needed 831 for USB, sound, many IDE/SATA chipsets and some other devices. 832 833 Newer systems typically have a modern AMD IOMMU, supported via 834 the CONFIG_AMD_IOMMU=y config option. 835 836 In normal configurations this driver is only active when needed: 837 there's more than 3 GB of memory and the system contains a 838 32-bit limited device. 839 840 If unsure, say Y. 841 842config CALGARY_IOMMU 843 bool "IBM Calgary IOMMU support" 844 select SWIOTLB 845 depends on X86_64 && PCI 846 ---help--- 847 Support for hardware IOMMUs in IBM's xSeries x366 and x460 848 systems. Needed to run systems with more than 3GB of memory 849 properly with 32-bit PCI devices that do not support DAC 850 (Double Address Cycle). Calgary also supports bus level 851 isolation, where all DMAs pass through the IOMMU. This 852 prevents them from going anywhere except their intended 853 destination. This catches hard-to-find kernel bugs and 854 mis-behaving drivers and devices that do not use the DMA-API 855 properly to set up their DMA buffers. The IOMMU can be 856 turned off at boot time with the iommu=off parameter. 857 Normally the kernel will make the right choice by itself. 858 If unsure, say Y. 859 860config CALGARY_IOMMU_ENABLED_BY_DEFAULT 861 def_bool y 862 prompt "Should Calgary be enabled by default?" 863 depends on CALGARY_IOMMU 864 ---help--- 865 Should Calgary be enabled by default? if you choose 'y', Calgary 866 will be used (if it exists). If you choose 'n', Calgary will not be 867 used even if it exists. If you choose 'n' and would like to use 868 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 869 If unsure, say Y. 870 871# need this always selected by IOMMU for the VIA workaround 872config SWIOTLB 873 def_bool y if X86_64 874 ---help--- 875 Support for software bounce buffers used on x86-64 systems 876 which don't have a hardware IOMMU. Using this PCI devices 877 which can only access 32-bits of memory can be used on systems 878 with more than 3 GB of memory. 879 If unsure, say Y. 880 881config IOMMU_HELPER 882 def_bool y 883 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 884 885config MAXSMP 886 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 887 depends on X86_64 && SMP && DEBUG_KERNEL 888 select CPUMASK_OFFSTACK 889 ---help--- 890 Enable maximum number of CPUS and NUMA Nodes for this architecture. 891 If unsure, say N. 892 893config NR_CPUS 894 int "Maximum number of CPUs" if SMP && !MAXSMP 895 range 2 8 if SMP && X86_32 && !X86_BIGSMP 896 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 897 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 898 default "1" if !SMP 899 default "8192" if MAXSMP 900 default "32" if SMP && X86_BIGSMP 901 default "8" if SMP && X86_32 902 default "64" if SMP 903 ---help--- 904 This allows you to specify the maximum number of CPUs which this 905 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 906 supported value is 8192, otherwise the maximum value is 512. The 907 minimum value which makes sense is 2. 908 909 This is purely to save memory - each supported CPU adds 910 approximately eight kilobytes to the kernel image. 911 912config SCHED_SMT 913 bool "SMT (Hyperthreading) scheduler support" 914 depends on SMP 915 ---help--- 916 SMT scheduler support improves the CPU scheduler's decision making 917 when dealing with Intel Pentium 4 chips with HyperThreading at a 918 cost of slightly increased overhead in some places. If unsure say 919 N here. 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 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 1045source "arch/x86/events/Kconfig" 1046 1047config X86_LEGACY_VM86 1048 bool "Legacy VM86 support" 1049 default n 1050 depends on X86_32 1051 ---help--- 1052 This option allows user programs to put the CPU into V8086 1053 mode, which is an 80286-era approximation of 16-bit real mode. 1054 1055 Some very old versions of X and/or vbetool require this option 1056 for user mode setting. Similarly, DOSEMU will use it if 1057 available to accelerate real mode DOS programs. However, any 1058 recent version of DOSEMU, X, or vbetool should be fully 1059 functional even without kernel VM86 support, as they will all 1060 fall back to software emulation. Nevertheless, if you are using 1061 a 16-bit DOS program where 16-bit performance matters, vm86 1062 mode might be faster than emulation and you might want to 1063 enable this option. 1064 1065 Note that any app that works on a 64-bit kernel is unlikely to 1066 need this option, as 64-bit kernels don't, and can't, support 1067 V8086 mode. This option is also unrelated to 16-bit protected 1068 mode and is not needed to run most 16-bit programs under Wine. 1069 1070 Enabling this option increases the complexity of the kernel 1071 and slows down exception handling a tiny bit. 1072 1073 If unsure, say N here. 1074 1075config VM86 1076 bool 1077 default X86_LEGACY_VM86 1078 1079config X86_16BIT 1080 bool "Enable support for 16-bit segments" if EXPERT 1081 default y 1082 depends on MODIFY_LDT_SYSCALL 1083 ---help--- 1084 This option is required by programs like Wine to run 16-bit 1085 protected mode legacy code on x86 processors. Disabling 1086 this option saves about 300 bytes on i386, or around 6K text 1087 plus 16K runtime memory on x86-64, 1088 1089config X86_ESPFIX32 1090 def_bool y 1091 depends on X86_16BIT && X86_32 1092 1093config X86_ESPFIX64 1094 def_bool y 1095 depends on X86_16BIT && X86_64 1096 1097config X86_VSYSCALL_EMULATION 1098 bool "Enable vsyscall emulation" if EXPERT 1099 default y 1100 depends on X86_64 1101 ---help--- 1102 This enables emulation of the legacy vsyscall page. Disabling 1103 it is roughly equivalent to booting with vsyscall=none, except 1104 that it will also disable the helpful warning if a program 1105 tries to use a vsyscall. With this option set to N, offending 1106 programs will just segfault, citing addresses of the form 1107 0xffffffffff600?00. 1108 1109 This option is required by many programs built before 2013, and 1110 care should be used even with newer programs if set to N. 1111 1112 Disabling this option saves about 7K of kernel size and 1113 possibly 4K of additional runtime pagetable memory. 1114 1115config TOSHIBA 1116 tristate "Toshiba Laptop support" 1117 depends on X86_32 1118 ---help--- 1119 This adds a driver to safely access the System Management Mode of 1120 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1121 not work on models with a Phoenix BIOS. The System Management Mode 1122 is used to set the BIOS and power saving options on Toshiba portables. 1123 1124 For information on utilities to make use of this driver see the 1125 Toshiba Linux utilities web site at: 1126 <http://www.buzzard.org.uk/toshiba/>. 1127 1128 Say Y if you intend to run this kernel on a Toshiba portable. 1129 Say N otherwise. 1130 1131config I8K 1132 tristate "Dell i8k legacy laptop support" 1133 select HWMON 1134 select SENSORS_DELL_SMM 1135 ---help--- 1136 This option enables legacy /proc/i8k userspace interface in hwmon 1137 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1138 temperature and allows controlling fan speeds of Dell laptops via 1139 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1140 it reports also power and hotkey status. For fan speed control is 1141 needed userspace package i8kutils. 1142 1143 Say Y if you intend to run this kernel on old Dell laptops or want to 1144 use userspace package i8kutils. 1145 Say N otherwise. 1146 1147config X86_REBOOTFIXUPS 1148 bool "Enable X86 board specific fixups for reboot" 1149 depends on X86_32 1150 ---help--- 1151 This enables chipset and/or board specific fixups to be done 1152 in order to get reboot to work correctly. This is only needed on 1153 some combinations of hardware and BIOS. The symptom, for which 1154 this config is intended, is when reboot ends with a stalled/hung 1155 system. 1156 1157 Currently, the only fixup is for the Geode machines using 1158 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1159 1160 Say Y if you want to enable the fixup. Currently, it's safe to 1161 enable this option even if you don't need it. 1162 Say N otherwise. 1163 1164config MICROCODE 1165 bool "CPU microcode loading support" 1166 default y 1167 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1168 select FW_LOADER 1169 ---help--- 1170 If you say Y here, you will be able to update the microcode on 1171 Intel and AMD processors. The Intel support is for the IA32 family, 1172 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1173 AMD support is for families 0x10 and later. You will obviously need 1174 the actual microcode binary data itself which is not shipped with 1175 the Linux kernel. 1176 1177 The preferred method to load microcode from a detached initrd is described 1178 in Documentation/x86/early-microcode.txt. For that you need to enable 1179 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1180 initrd for microcode blobs. 1181 1182 In addition, you can build-in the microcode into the kernel. For that you 1183 need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 1184 to the CONFIG_EXTRA_FIRMWARE config option. 1185 1186config MICROCODE_INTEL 1187 bool "Intel microcode loading support" 1188 depends on MICROCODE 1189 default MICROCODE 1190 select FW_LOADER 1191 ---help--- 1192 This options enables microcode patch loading support for Intel 1193 processors. 1194 1195 For the current Intel microcode data package go to 1196 <https://downloadcenter.intel.com> and search for 1197 'Linux Processor Microcode Data File'. 1198 1199config MICROCODE_AMD 1200 bool "AMD microcode loading support" 1201 depends on MICROCODE 1202 select FW_LOADER 1203 ---help--- 1204 If you select this option, microcode patch loading support for AMD 1205 processors will be enabled. 1206 1207config MICROCODE_OLD_INTERFACE 1208 def_bool y 1209 depends on MICROCODE 1210 1211config X86_MSR 1212 tristate "/dev/cpu/*/msr - Model-specific register support" 1213 ---help--- 1214 This device gives privileged processes access to the x86 1215 Model-Specific Registers (MSRs). It is a character device with 1216 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1217 MSR accesses are directed to a specific CPU on multi-processor 1218 systems. 1219 1220config X86_CPUID 1221 tristate "/dev/cpu/*/cpuid - CPU information support" 1222 ---help--- 1223 This device gives processes access to the x86 CPUID instruction to 1224 be executed on a specific processor. It is a character device 1225 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1226 /dev/cpu/31/cpuid. 1227 1228choice 1229 prompt "High Memory Support" 1230 default HIGHMEM4G 1231 depends on X86_32 1232 1233config NOHIGHMEM 1234 bool "off" 1235 ---help--- 1236 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1237 However, the address space of 32-bit x86 processors is only 4 1238 Gigabytes large. That means that, if you have a large amount of 1239 physical memory, not all of it can be "permanently mapped" by the 1240 kernel. The physical memory that's not permanently mapped is called 1241 "high memory". 1242 1243 If you are compiling a kernel which will never run on a machine with 1244 more than 1 Gigabyte total physical RAM, answer "off" here (default 1245 choice and suitable for most users). This will result in a "3GB/1GB" 1246 split: 3GB are mapped so that each process sees a 3GB virtual memory 1247 space and the remaining part of the 4GB virtual memory space is used 1248 by the kernel to permanently map as much physical memory as 1249 possible. 1250 1251 If the machine has between 1 and 4 Gigabytes physical RAM, then 1252 answer "4GB" here. 1253 1254 If more than 4 Gigabytes is used then answer "64GB" here. This 1255 selection turns Intel PAE (Physical Address Extension) mode on. 1256 PAE implements 3-level paging on IA32 processors. PAE is fully 1257 supported by Linux, PAE mode is implemented on all recent Intel 1258 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1259 then the kernel will not boot on CPUs that don't support PAE! 1260 1261 The actual amount of total physical memory will either be 1262 auto detected or can be forced by using a kernel command line option 1263 such as "mem=256M". (Try "man bootparam" or see the documentation of 1264 your boot loader (lilo or loadlin) about how to pass options to the 1265 kernel at boot time.) 1266 1267 If unsure, say "off". 1268 1269config HIGHMEM4G 1270 bool "4GB" 1271 ---help--- 1272 Select this if you have a 32-bit processor and between 1 and 4 1273 gigabytes of physical RAM. 1274 1275config HIGHMEM64G 1276 bool "64GB" 1277 depends on !M486 1278 select X86_PAE 1279 ---help--- 1280 Select this if you have a 32-bit processor and more than 4 1281 gigabytes of physical RAM. 1282 1283endchoice 1284 1285choice 1286 prompt "Memory split" if EXPERT 1287 default VMSPLIT_3G 1288 depends on X86_32 1289 ---help--- 1290 Select the desired split between kernel and user memory. 1291 1292 If the address range available to the kernel is less than the 1293 physical memory installed, the remaining memory will be available 1294 as "high memory". Accessing high memory is a little more costly 1295 than low memory, as it needs to be mapped into the kernel first. 1296 Note that increasing the kernel address space limits the range 1297 available to user programs, making the address space there 1298 tighter. Selecting anything other than the default 3G/1G split 1299 will also likely make your kernel incompatible with binary-only 1300 kernel modules. 1301 1302 If you are not absolutely sure what you are doing, leave this 1303 option alone! 1304 1305 config VMSPLIT_3G 1306 bool "3G/1G user/kernel split" 1307 config VMSPLIT_3G_OPT 1308 depends on !X86_PAE 1309 bool "3G/1G user/kernel split (for full 1G low memory)" 1310 config VMSPLIT_2G 1311 bool "2G/2G user/kernel split" 1312 config VMSPLIT_2G_OPT 1313 depends on !X86_PAE 1314 bool "2G/2G user/kernel split (for full 2G low memory)" 1315 config VMSPLIT_1G 1316 bool "1G/3G user/kernel split" 1317endchoice 1318 1319config PAGE_OFFSET 1320 hex 1321 default 0xB0000000 if VMSPLIT_3G_OPT 1322 default 0x80000000 if VMSPLIT_2G 1323 default 0x78000000 if VMSPLIT_2G_OPT 1324 default 0x40000000 if VMSPLIT_1G 1325 default 0xC0000000 1326 depends on X86_32 1327 1328config HIGHMEM 1329 def_bool y 1330 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1331 1332config X86_PAE 1333 bool "PAE (Physical Address Extension) Support" 1334 depends on X86_32 && !HIGHMEM4G 1335 select SWIOTLB 1336 ---help--- 1337 PAE is required for NX support, and furthermore enables 1338 larger swapspace support for non-overcommit purposes. It 1339 has the cost of more pagetable lookup overhead, and also 1340 consumes more pagetable space per process. 1341 1342config ARCH_PHYS_ADDR_T_64BIT 1343 def_bool y 1344 depends on X86_64 || X86_PAE 1345 1346config ARCH_DMA_ADDR_T_64BIT 1347 def_bool y 1348 depends on X86_64 || HIGHMEM64G 1349 1350config X86_DIRECT_GBPAGES 1351 def_bool y 1352 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1353 ---help--- 1354 Certain kernel features effectively disable kernel 1355 linear 1 GB mappings (even if the CPU otherwise 1356 supports them), so don't confuse the user by printing 1357 that we have them enabled. 1358 1359# Common NUMA Features 1360config NUMA 1361 bool "Numa Memory Allocation and Scheduler Support" 1362 depends on SMP 1363 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1364 default y if X86_BIGSMP 1365 ---help--- 1366 Enable NUMA (Non Uniform Memory Access) support. 1367 1368 The kernel will try to allocate memory used by a CPU on the 1369 local memory controller of the CPU and add some more 1370 NUMA awareness to the kernel. 1371 1372 For 64-bit this is recommended if the system is Intel Core i7 1373 (or later), AMD Opteron, or EM64T NUMA. 1374 1375 For 32-bit this is only needed if you boot a 32-bit 1376 kernel on a 64-bit NUMA platform. 1377 1378 Otherwise, you should say N. 1379 1380config AMD_NUMA 1381 def_bool y 1382 prompt "Old style AMD Opteron NUMA detection" 1383 depends on X86_64 && NUMA && PCI 1384 ---help--- 1385 Enable AMD NUMA node topology detection. You should say Y here if 1386 you have a multi processor AMD system. This uses an old method to 1387 read the NUMA configuration directly from the builtin Northbridge 1388 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1389 which also takes priority if both are compiled in. 1390 1391config X86_64_ACPI_NUMA 1392 def_bool y 1393 prompt "ACPI NUMA detection" 1394 depends on X86_64 && NUMA && ACPI && PCI 1395 select ACPI_NUMA 1396 ---help--- 1397 Enable ACPI SRAT based node topology detection. 1398 1399# Some NUMA nodes have memory ranges that span 1400# other nodes. Even though a pfn is valid and 1401# between a node's start and end pfns, it may not 1402# reside on that node. See memmap_init_zone() 1403# for details. 1404config NODES_SPAN_OTHER_NODES 1405 def_bool y 1406 depends on X86_64_ACPI_NUMA 1407 1408config NUMA_EMU 1409 bool "NUMA emulation" 1410 depends on NUMA 1411 ---help--- 1412 Enable NUMA emulation. A flat machine will be split 1413 into virtual nodes when booted with "numa=fake=N", where N is the 1414 number of nodes. This is only useful for debugging. 1415 1416config NODES_SHIFT 1417 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1418 range 1 10 1419 default "10" if MAXSMP 1420 default "6" if X86_64 1421 default "3" 1422 depends on NEED_MULTIPLE_NODES 1423 ---help--- 1424 Specify the maximum number of NUMA Nodes available on the target 1425 system. Increases memory reserved to accommodate various tables. 1426 1427config ARCH_HAVE_MEMORY_PRESENT 1428 def_bool y 1429 depends on X86_32 && DISCONTIGMEM 1430 1431config NEED_NODE_MEMMAP_SIZE 1432 def_bool y 1433 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1434 1435config ARCH_FLATMEM_ENABLE 1436 def_bool y 1437 depends on X86_32 && !NUMA 1438 1439config ARCH_DISCONTIGMEM_ENABLE 1440 def_bool y 1441 depends on NUMA && X86_32 1442 1443config ARCH_DISCONTIGMEM_DEFAULT 1444 def_bool y 1445 depends on NUMA && X86_32 1446 1447config ARCH_SPARSEMEM_ENABLE 1448 def_bool y 1449 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1450 select SPARSEMEM_STATIC if X86_32 1451 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1452 1453config ARCH_SPARSEMEM_DEFAULT 1454 def_bool y 1455 depends on X86_64 1456 1457config ARCH_SELECT_MEMORY_MODEL 1458 def_bool y 1459 depends on ARCH_SPARSEMEM_ENABLE 1460 1461config ARCH_MEMORY_PROBE 1462 bool "Enable sysfs memory/probe interface" 1463 depends on X86_64 && MEMORY_HOTPLUG 1464 help 1465 This option enables a sysfs memory/probe interface for testing. 1466 See Documentation/memory-hotplug.txt for more information. 1467 If you are unsure how to answer this question, answer N. 1468 1469config ARCH_PROC_KCORE_TEXT 1470 def_bool y 1471 depends on X86_64 && PROC_KCORE 1472 1473config ILLEGAL_POINTER_VALUE 1474 hex 1475 default 0 if X86_32 1476 default 0xdead000000000000 if X86_64 1477 1478source "mm/Kconfig" 1479 1480config X86_PMEM_LEGACY_DEVICE 1481 bool 1482 1483config X86_PMEM_LEGACY 1484 tristate "Support non-standard NVDIMMs and ADR protected memory" 1485 depends on PHYS_ADDR_T_64BIT 1486 depends on BLK_DEV 1487 select X86_PMEM_LEGACY_DEVICE 1488 select LIBNVDIMM 1489 help 1490 Treat memory marked using the non-standard e820 type of 12 as used 1491 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1492 The kernel will offer these regions to the 'pmem' driver so 1493 they can be used for persistent storage. 1494 1495 Say Y if unsure. 1496 1497config HIGHPTE 1498 bool "Allocate 3rd-level pagetables from highmem" 1499 depends on HIGHMEM 1500 ---help--- 1501 The VM uses one page table entry for each page of physical memory. 1502 For systems with a lot of RAM, this can be wasteful of precious 1503 low memory. Setting this option will put user-space page table 1504 entries in high memory. 1505 1506config X86_CHECK_BIOS_CORRUPTION 1507 bool "Check for low memory corruption" 1508 ---help--- 1509 Periodically check for memory corruption in low memory, which 1510 is suspected to be caused by BIOS. Even when enabled in the 1511 configuration, it is disabled at runtime. Enable it by 1512 setting "memory_corruption_check=1" on the kernel command 1513 line. By default it scans the low 64k of memory every 60 1514 seconds; see the memory_corruption_check_size and 1515 memory_corruption_check_period parameters in 1516 Documentation/kernel-parameters.txt to adjust this. 1517 1518 When enabled with the default parameters, this option has 1519 almost no overhead, as it reserves a relatively small amount 1520 of memory and scans it infrequently. It both detects corruption 1521 and prevents it from affecting the running system. 1522 1523 It is, however, intended as a diagnostic tool; if repeatable 1524 BIOS-originated corruption always affects the same memory, 1525 you can use memmap= to prevent the kernel from using that 1526 memory. 1527 1528config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1529 bool "Set the default setting of memory_corruption_check" 1530 depends on X86_CHECK_BIOS_CORRUPTION 1531 default y 1532 ---help--- 1533 Set whether the default state of memory_corruption_check is 1534 on or off. 1535 1536config X86_RESERVE_LOW 1537 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1538 default 64 1539 range 4 640 1540 ---help--- 1541 Specify the amount of low memory to reserve for the BIOS. 1542 1543 The first page contains BIOS data structures that the kernel 1544 must not use, so that page must always be reserved. 1545 1546 By default we reserve the first 64K of physical RAM, as a 1547 number of BIOSes are known to corrupt that memory range 1548 during events such as suspend/resume or monitor cable 1549 insertion, so it must not be used by the kernel. 1550 1551 You can set this to 4 if you are absolutely sure that you 1552 trust the BIOS to get all its memory reservations and usages 1553 right. If you know your BIOS have problems beyond the 1554 default 64K area, you can set this to 640 to avoid using the 1555 entire low memory range. 1556 1557 If you have doubts about the BIOS (e.g. suspend/resume does 1558 not work or there's kernel crashes after certain hardware 1559 hotplug events) then you might want to enable 1560 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1561 typical corruption patterns. 1562 1563 Leave this to the default value of 64 if you are unsure. 1564 1565config MATH_EMULATION 1566 bool 1567 depends on MODIFY_LDT_SYSCALL 1568 prompt "Math emulation" if X86_32 1569 ---help--- 1570 Linux can emulate a math coprocessor (used for floating point 1571 operations) if you don't have one. 486DX and Pentium processors have 1572 a math coprocessor built in, 486SX and 386 do not, unless you added 1573 a 487DX or 387, respectively. (The messages during boot time can 1574 give you some hints here ["man dmesg"].) Everyone needs either a 1575 coprocessor or this emulation. 1576 1577 If you don't have a math coprocessor, you need to say Y here; if you 1578 say Y here even though you have a coprocessor, the coprocessor will 1579 be used nevertheless. (This behavior can be changed with the kernel 1580 command line option "no387", which comes handy if your coprocessor 1581 is broken. Try "man bootparam" or see the documentation of your boot 1582 loader (lilo or loadlin) about how to pass options to the kernel at 1583 boot time.) This means that it is a good idea to say Y here if you 1584 intend to use this kernel on different machines. 1585 1586 More information about the internals of the Linux math coprocessor 1587 emulation can be found in <file:arch/x86/math-emu/README>. 1588 1589 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1590 kernel, it won't hurt. 1591 1592config MTRR 1593 def_bool y 1594 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1595 ---help--- 1596 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1597 the Memory Type Range Registers (MTRRs) may be used to control 1598 processor access to memory ranges. This is most useful if you have 1599 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1600 allows bus write transfers to be combined into a larger transfer 1601 before bursting over the PCI/AGP bus. This can increase performance 1602 of image write operations 2.5 times or more. Saying Y here creates a 1603 /proc/mtrr file which may be used to manipulate your processor's 1604 MTRRs. Typically the X server should use this. 1605 1606 This code has a reasonably generic interface so that similar 1607 control registers on other processors can be easily supported 1608 as well: 1609 1610 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1611 Registers (ARRs) which provide a similar functionality to MTRRs. For 1612 these, the ARRs are used to emulate the MTRRs. 1613 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1614 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1615 write-combining. All of these processors are supported by this code 1616 and it makes sense to say Y here if you have one of them. 1617 1618 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1619 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1620 can lead to all sorts of problems, so it's good to say Y here. 1621 1622 You can safely say Y even if your machine doesn't have MTRRs, you'll 1623 just add about 9 KB to your kernel. 1624 1625 See <file:Documentation/x86/mtrr.txt> for more information. 1626 1627config MTRR_SANITIZER 1628 def_bool y 1629 prompt "MTRR cleanup support" 1630 depends on MTRR 1631 ---help--- 1632 Convert MTRR layout from continuous to discrete, so X drivers can 1633 add writeback entries. 1634 1635 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1636 The largest mtrr entry size for a continuous block can be set with 1637 mtrr_chunk_size. 1638 1639 If unsure, say Y. 1640 1641config MTRR_SANITIZER_ENABLE_DEFAULT 1642 int "MTRR cleanup enable value (0-1)" 1643 range 0 1 1644 default "0" 1645 depends on MTRR_SANITIZER 1646 ---help--- 1647 Enable mtrr cleanup default value 1648 1649config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1650 int "MTRR cleanup spare reg num (0-7)" 1651 range 0 7 1652 default "1" 1653 depends on MTRR_SANITIZER 1654 ---help--- 1655 mtrr cleanup spare entries default, it can be changed via 1656 mtrr_spare_reg_nr=N on the kernel command line. 1657 1658config X86_PAT 1659 def_bool y 1660 prompt "x86 PAT support" if EXPERT 1661 depends on MTRR 1662 ---help--- 1663 Use PAT attributes to setup page level cache control. 1664 1665 PATs are the modern equivalents of MTRRs and are much more 1666 flexible than MTRRs. 1667 1668 Say N here if you see bootup problems (boot crash, boot hang, 1669 spontaneous reboots) or a non-working video driver. 1670 1671 If unsure, say Y. 1672 1673config ARCH_USES_PG_UNCACHED 1674 def_bool y 1675 depends on X86_PAT 1676 1677config ARCH_RANDOM 1678 def_bool y 1679 prompt "x86 architectural random number generator" if EXPERT 1680 ---help--- 1681 Enable the x86 architectural RDRAND instruction 1682 (Intel Bull Mountain technology) to generate random numbers. 1683 If supported, this is a high bandwidth, cryptographically 1684 secure hardware random number generator. 1685 1686config X86_SMAP 1687 def_bool y 1688 prompt "Supervisor Mode Access Prevention" if EXPERT 1689 ---help--- 1690 Supervisor Mode Access Prevention (SMAP) is a security 1691 feature in newer Intel processors. There is a small 1692 performance cost if this enabled and turned on; there is 1693 also a small increase in the kernel size if this is enabled. 1694 1695 If unsure, say Y. 1696 1697config X86_INTEL_MPX 1698 prompt "Intel MPX (Memory Protection Extensions)" 1699 def_bool n 1700 depends on CPU_SUP_INTEL 1701 ---help--- 1702 MPX provides hardware features that can be used in 1703 conjunction with compiler-instrumented code to check 1704 memory references. It is designed to detect buffer 1705 overflow or underflow bugs. 1706 1707 This option enables running applications which are 1708 instrumented or otherwise use MPX. It does not use MPX 1709 itself inside the kernel or to protect the kernel 1710 against bad memory references. 1711 1712 Enabling this option will make the kernel larger: 1713 ~8k of kernel text and 36 bytes of data on a 64-bit 1714 defconfig. It adds a long to the 'mm_struct' which 1715 will increase the kernel memory overhead of each 1716 process and adds some branches to paths used during 1717 exec() and munmap(). 1718 1719 For details, see Documentation/x86/intel_mpx.txt 1720 1721 If unsure, say N. 1722 1723config X86_INTEL_MEMORY_PROTECTION_KEYS 1724 prompt "Intel Memory Protection Keys" 1725 def_bool y 1726 # Note: only available in 64-bit mode 1727 depends on CPU_SUP_INTEL && X86_64 1728 ---help--- 1729 Memory Protection Keys provides a mechanism for enforcing 1730 page-based protections, but without requiring modification of the 1731 page tables when an application changes protection domains. 1732 1733 For details, see Documentation/x86/protection-keys.txt 1734 1735 If unsure, say y. 1736 1737config EFI 1738 bool "EFI runtime service support" 1739 depends on ACPI 1740 select UCS2_STRING 1741 select EFI_RUNTIME_WRAPPERS 1742 ---help--- 1743 This enables the kernel to use EFI runtime services that are 1744 available (such as the EFI variable services). 1745 1746 This option is only useful on systems that have EFI firmware. 1747 In addition, you should use the latest ELILO loader available 1748 at <http://elilo.sourceforge.net> in order to take advantage 1749 of EFI runtime services. However, even with this option, the 1750 resultant kernel should continue to boot on existing non-EFI 1751 platforms. 1752 1753config EFI_STUB 1754 bool "EFI stub support" 1755 depends on EFI && !X86_USE_3DNOW 1756 select RELOCATABLE 1757 ---help--- 1758 This kernel feature allows a bzImage to be loaded directly 1759 by EFI firmware without the use of a bootloader. 1760 1761 See Documentation/efi-stub.txt for more information. 1762 1763config EFI_MIXED 1764 bool "EFI mixed-mode support" 1765 depends on EFI_STUB && X86_64 1766 ---help--- 1767 Enabling this feature allows a 64-bit kernel to be booted 1768 on a 32-bit firmware, provided that your CPU supports 64-bit 1769 mode. 1770 1771 Note that it is not possible to boot a mixed-mode enabled 1772 kernel via the EFI boot stub - a bootloader that supports 1773 the EFI handover protocol must be used. 1774 1775 If unsure, say N. 1776 1777config SECCOMP 1778 def_bool y 1779 prompt "Enable seccomp to safely compute untrusted bytecode" 1780 ---help--- 1781 This kernel feature is useful for number crunching applications 1782 that may need to compute untrusted bytecode during their 1783 execution. By using pipes or other transports made available to 1784 the process as file descriptors supporting the read/write 1785 syscalls, it's possible to isolate those applications in 1786 their own address space using seccomp. Once seccomp is 1787 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1788 and the task is only allowed to execute a few safe syscalls 1789 defined by each seccomp mode. 1790 1791 If unsure, say Y. Only embedded should say N here. 1792 1793source kernel/Kconfig.hz 1794 1795config KEXEC 1796 bool "kexec system call" 1797 select KEXEC_CORE 1798 ---help--- 1799 kexec is a system call that implements the ability to shutdown your 1800 current kernel, and to start another kernel. It is like a reboot 1801 but it is independent of the system firmware. And like a reboot 1802 you can start any kernel with it, not just Linux. 1803 1804 The name comes from the similarity to the exec system call. 1805 1806 It is an ongoing process to be certain the hardware in a machine 1807 is properly shutdown, so do not be surprised if this code does not 1808 initially work for you. As of this writing the exact hardware 1809 interface is strongly in flux, so no good recommendation can be 1810 made. 1811 1812config KEXEC_FILE 1813 bool "kexec file based system call" 1814 select KEXEC_CORE 1815 select BUILD_BIN2C 1816 depends on X86_64 1817 depends on CRYPTO=y 1818 depends on CRYPTO_SHA256=y 1819 ---help--- 1820 This is new version of kexec system call. This system call is 1821 file based and takes file descriptors as system call argument 1822 for kernel and initramfs as opposed to list of segments as 1823 accepted by previous system call. 1824 1825config KEXEC_VERIFY_SIG 1826 bool "Verify kernel signature during kexec_file_load() syscall" 1827 depends on KEXEC_FILE 1828 ---help--- 1829 This option makes kernel signature verification mandatory for 1830 the kexec_file_load() syscall. 1831 1832 In addition to that option, you need to enable signature 1833 verification for the corresponding kernel image type being 1834 loaded in order for this to work. 1835 1836config KEXEC_BZIMAGE_VERIFY_SIG 1837 bool "Enable bzImage signature verification support" 1838 depends on KEXEC_VERIFY_SIG 1839 depends on SIGNED_PE_FILE_VERIFICATION 1840 select SYSTEM_TRUSTED_KEYRING 1841 ---help--- 1842 Enable bzImage signature verification support. 1843 1844config CRASH_DUMP 1845 bool "kernel crash dumps" 1846 depends on X86_64 || (X86_32 && HIGHMEM) 1847 ---help--- 1848 Generate crash dump after being started by kexec. 1849 This should be normally only set in special crash dump kernels 1850 which are loaded in the main kernel with kexec-tools into 1851 a specially reserved region and then later executed after 1852 a crash by kdump/kexec. The crash dump kernel must be compiled 1853 to a memory address not used by the main kernel or BIOS using 1854 PHYSICAL_START, or it must be built as a relocatable image 1855 (CONFIG_RELOCATABLE=y). 1856 For more details see Documentation/kdump/kdump.txt 1857 1858config KEXEC_JUMP 1859 bool "kexec jump" 1860 depends on KEXEC && HIBERNATION 1861 ---help--- 1862 Jump between original kernel and kexeced kernel and invoke 1863 code in physical address mode via KEXEC 1864 1865config PHYSICAL_START 1866 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1867 default "0x1000000" 1868 ---help--- 1869 This gives the physical address where the kernel is loaded. 1870 1871 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1872 bzImage will decompress itself to above physical address and 1873 run from there. Otherwise, bzImage will run from the address where 1874 it has been loaded by the boot loader and will ignore above physical 1875 address. 1876 1877 In normal kdump cases one does not have to set/change this option 1878 as now bzImage can be compiled as a completely relocatable image 1879 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1880 address. This option is mainly useful for the folks who don't want 1881 to use a bzImage for capturing the crash dump and want to use a 1882 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1883 to be specifically compiled to run from a specific memory area 1884 (normally a reserved region) and this option comes handy. 1885 1886 So if you are using bzImage for capturing the crash dump, 1887 leave the value here unchanged to 0x1000000 and set 1888 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1889 for capturing the crash dump change this value to start of 1890 the reserved region. In other words, it can be set based on 1891 the "X" value as specified in the "crashkernel=YM@XM" 1892 command line boot parameter passed to the panic-ed 1893 kernel. Please take a look at Documentation/kdump/kdump.txt 1894 for more details about crash dumps. 1895 1896 Usage of bzImage for capturing the crash dump is recommended as 1897 one does not have to build two kernels. Same kernel can be used 1898 as production kernel and capture kernel. Above option should have 1899 gone away after relocatable bzImage support is introduced. But it 1900 is present because there are users out there who continue to use 1901 vmlinux for dump capture. This option should go away down the 1902 line. 1903 1904 Don't change this unless you know what you are doing. 1905 1906config RELOCATABLE 1907 bool "Build a relocatable kernel" 1908 default y 1909 ---help--- 1910 This builds a kernel image that retains relocation information 1911 so it can be loaded someplace besides the default 1MB. 1912 The relocations tend to make the kernel binary about 10% larger, 1913 but are discarded at runtime. 1914 1915 One use is for the kexec on panic case where the recovery kernel 1916 must live at a different physical address than the primary 1917 kernel. 1918 1919 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1920 it has been loaded at and the compile time physical address 1921 (CONFIG_PHYSICAL_START) is used as the minimum location. 1922 1923config RANDOMIZE_BASE 1924 bool "Randomize the address of the kernel image (KASLR)" 1925 depends on RELOCATABLE 1926 default n 1927 ---help--- 1928 In support of Kernel Address Space Layout Randomization (KASLR), 1929 this randomizes the physical address at which the kernel image 1930 is decompressed and the virtual address where the kernel 1931 image is mapped, as a security feature that deters exploit 1932 attempts relying on knowledge of the location of kernel 1933 code internals. 1934 1935 On 64-bit, the kernel physical and virtual addresses are 1936 randomized separately. The physical address will be anywhere 1937 between 16MB and the top of physical memory (up to 64TB). The 1938 virtual address will be randomized from 16MB up to 1GB (9 bits 1939 of entropy). Note that this also reduces the memory space 1940 available to kernel modules from 1.5GB to 1GB. 1941 1942 On 32-bit, the kernel physical and virtual addresses are 1943 randomized together. They will be randomized from 16MB up to 1944 512MB (8 bits of entropy). 1945 1946 Entropy is generated using the RDRAND instruction if it is 1947 supported. If RDTSC is supported, its value is mixed into 1948 the entropy pool as well. If neither RDRAND nor RDTSC are 1949 supported, then entropy is read from the i8254 timer. The 1950 usable entropy is limited by the kernel being built using 1951 2GB addressing, and that PHYSICAL_ALIGN must be at a 1952 minimum of 2MB. As a result, only 10 bits of entropy are 1953 theoretically possible, but the implementations are further 1954 limited due to memory layouts. 1955 1956 If CONFIG_HIBERNATE is also enabled, KASLR is disabled at boot 1957 time. To enable it, boot with "kaslr" on the kernel command 1958 line (which will also disable hibernation). 1959 1960 If unsure, say N. 1961 1962# Relocation on x86 needs some additional build support 1963config X86_NEED_RELOCS 1964 def_bool y 1965 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1966 1967config PHYSICAL_ALIGN 1968 hex "Alignment value to which kernel should be aligned" 1969 default "0x200000" 1970 range 0x2000 0x1000000 if X86_32 1971 range 0x200000 0x1000000 if X86_64 1972 ---help--- 1973 This value puts the alignment restrictions on physical address 1974 where kernel is loaded and run from. Kernel is compiled for an 1975 address which meets above alignment restriction. 1976 1977 If bootloader loads the kernel at a non-aligned address and 1978 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1979 address aligned to above value and run from there. 1980 1981 If bootloader loads the kernel at a non-aligned address and 1982 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1983 load address and decompress itself to the address it has been 1984 compiled for and run from there. The address for which kernel is 1985 compiled already meets above alignment restrictions. Hence the 1986 end result is that kernel runs from a physical address meeting 1987 above alignment restrictions. 1988 1989 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1990 this value must be a multiple of 0x200000. 1991 1992 Don't change this unless you know what you are doing. 1993 1994config RANDOMIZE_MEMORY 1995 bool "Randomize the kernel memory sections" 1996 depends on X86_64 1997 depends on RANDOMIZE_BASE 1998 default RANDOMIZE_BASE 1999 ---help--- 2000 Randomizes the base virtual address of kernel memory sections 2001 (physical memory mapping, vmalloc & vmemmap). This security feature 2002 makes exploits relying on predictable memory locations less reliable. 2003 2004 The order of allocations remains unchanged. Entropy is generated in 2005 the same way as RANDOMIZE_BASE. Current implementation in the optimal 2006 configuration have in average 30,000 different possible virtual 2007 addresses for each memory section. 2008 2009 If unsure, say N. 2010 2011config RANDOMIZE_MEMORY_PHYSICAL_PADDING 2012 hex "Physical memory mapping padding" if EXPERT 2013 depends on RANDOMIZE_MEMORY 2014 default "0xa" if MEMORY_HOTPLUG 2015 default "0x0" 2016 range 0x1 0x40 if MEMORY_HOTPLUG 2017 range 0x0 0x40 2018 ---help--- 2019 Define the padding in terabytes added to the existing physical 2020 memory size during kernel memory randomization. It is useful 2021 for memory hotplug support but reduces the entropy available for 2022 address randomization. 2023 2024 If unsure, leave at the default value. 2025 2026config HOTPLUG_CPU 2027 bool "Support for hot-pluggable CPUs" 2028 depends on SMP 2029 ---help--- 2030 Say Y here to allow turning CPUs off and on. CPUs can be 2031 controlled through /sys/devices/system/cpu. 2032 ( Note: power management support will enable this option 2033 automatically on SMP systems. ) 2034 Say N if you want to disable CPU hotplug. 2035 2036config BOOTPARAM_HOTPLUG_CPU0 2037 bool "Set default setting of cpu0_hotpluggable" 2038 default n 2039 depends on HOTPLUG_CPU 2040 ---help--- 2041 Set whether default state of cpu0_hotpluggable is on or off. 2042 2043 Say Y here to enable CPU0 hotplug by default. If this switch 2044 is turned on, there is no need to give cpu0_hotplug kernel 2045 parameter and the CPU0 hotplug feature is enabled by default. 2046 2047 Please note: there are two known CPU0 dependencies if you want 2048 to enable the CPU0 hotplug feature either by this switch or by 2049 cpu0_hotplug kernel parameter. 2050 2051 First, resume from hibernate or suspend always starts from CPU0. 2052 So hibernate and suspend are prevented if CPU0 is offline. 2053 2054 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2055 offline if any interrupt can not migrate out of CPU0. There may 2056 be other CPU0 dependencies. 2057 2058 Please make sure the dependencies are under your control before 2059 you enable this feature. 2060 2061 Say N if you don't want to enable CPU0 hotplug feature by default. 2062 You still can enable the CPU0 hotplug feature at boot by kernel 2063 parameter cpu0_hotplug. 2064 2065config DEBUG_HOTPLUG_CPU0 2066 def_bool n 2067 prompt "Debug CPU0 hotplug" 2068 depends on HOTPLUG_CPU 2069 ---help--- 2070 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2071 soon as possible and boots up userspace with CPU0 offlined. User 2072 can online CPU0 back after boot time. 2073 2074 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2075 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2076 compilation or giving cpu0_hotplug kernel parameter at boot. 2077 2078 If unsure, say N. 2079 2080config COMPAT_VDSO 2081 def_bool n 2082 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2083 depends on X86_32 || IA32_EMULATION 2084 ---help--- 2085 Certain buggy versions of glibc will crash if they are 2086 presented with a 32-bit vDSO that is not mapped at the address 2087 indicated in its segment table. 2088 2089 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2090 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2091 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2092 the only released version with the bug, but OpenSUSE 9 2093 contains a buggy "glibc 2.3.2". 2094 2095 The symptom of the bug is that everything crashes on startup, saying: 2096 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2097 2098 Saying Y here changes the default value of the vdso32 boot 2099 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2100 This works around the glibc bug but hurts performance. 2101 2102 If unsure, say N: if you are compiling your own kernel, you 2103 are unlikely to be using a buggy version of glibc. 2104 2105choice 2106 prompt "vsyscall table for legacy applications" 2107 depends on X86_64 2108 default LEGACY_VSYSCALL_EMULATE 2109 help 2110 Legacy user code that does not know how to find the vDSO expects 2111 to be able to issue three syscalls by calling fixed addresses in 2112 kernel space. Since this location is not randomized with ASLR, 2113 it can be used to assist security vulnerability exploitation. 2114 2115 This setting can be changed at boot time via the kernel command 2116 line parameter vsyscall=[native|emulate|none]. 2117 2118 On a system with recent enough glibc (2.14 or newer) and no 2119 static binaries, you can say None without a performance penalty 2120 to improve security. 2121 2122 If unsure, select "Emulate". 2123 2124 config LEGACY_VSYSCALL_NATIVE 2125 bool "Native" 2126 help 2127 Actual executable code is located in the fixed vsyscall 2128 address mapping, implementing time() efficiently. Since 2129 this makes the mapping executable, it can be used during 2130 security vulnerability exploitation (traditionally as 2131 ROP gadgets). This configuration is not recommended. 2132 2133 config LEGACY_VSYSCALL_EMULATE 2134 bool "Emulate" 2135 help 2136 The kernel traps and emulates calls into the fixed 2137 vsyscall address mapping. This makes the mapping 2138 non-executable, but it still contains known contents, 2139 which could be used in certain rare security vulnerability 2140 exploits. This configuration is recommended when userspace 2141 still uses the vsyscall area. 2142 2143 config LEGACY_VSYSCALL_NONE 2144 bool "None" 2145 help 2146 There will be no vsyscall mapping at all. This will 2147 eliminate any risk of ASLR bypass due to the vsyscall 2148 fixed address mapping. Attempts to use the vsyscalls 2149 will be reported to dmesg, so that either old or 2150 malicious userspace programs can be identified. 2151 2152endchoice 2153 2154config CMDLINE_BOOL 2155 bool "Built-in kernel command line" 2156 ---help--- 2157 Allow for specifying boot arguments to the kernel at 2158 build time. On some systems (e.g. embedded ones), it is 2159 necessary or convenient to provide some or all of the 2160 kernel boot arguments with the kernel itself (that is, 2161 to not rely on the boot loader to provide them.) 2162 2163 To compile command line arguments into the kernel, 2164 set this option to 'Y', then fill in the 2165 boot arguments in CONFIG_CMDLINE. 2166 2167 Systems with fully functional boot loaders (i.e. non-embedded) 2168 should leave this option set to 'N'. 2169 2170config CMDLINE 2171 string "Built-in kernel command string" 2172 depends on CMDLINE_BOOL 2173 default "" 2174 ---help--- 2175 Enter arguments here that should be compiled into the kernel 2176 image and used at boot time. If the boot loader provides a 2177 command line at boot time, it is appended to this string to 2178 form the full kernel command line, when the system boots. 2179 2180 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2181 change this behavior. 2182 2183 In most cases, the command line (whether built-in or provided 2184 by the boot loader) should specify the device for the root 2185 file system. 2186 2187config CMDLINE_OVERRIDE 2188 bool "Built-in command line overrides boot loader arguments" 2189 depends on CMDLINE_BOOL 2190 ---help--- 2191 Set this option to 'Y' to have the kernel ignore the boot loader 2192 command line, and use ONLY the built-in command line. 2193 2194 This is used to work around broken boot loaders. This should 2195 be set to 'N' under normal conditions. 2196 2197config MODIFY_LDT_SYSCALL 2198 bool "Enable the LDT (local descriptor table)" if EXPERT 2199 default y 2200 ---help--- 2201 Linux can allow user programs to install a per-process x86 2202 Local Descriptor Table (LDT) using the modify_ldt(2) system 2203 call. This is required to run 16-bit or segmented code such as 2204 DOSEMU or some Wine programs. It is also used by some very old 2205 threading libraries. 2206 2207 Enabling this feature adds a small amount of overhead to 2208 context switches and increases the low-level kernel attack 2209 surface. Disabling it removes the modify_ldt(2) system call. 2210 2211 Saying 'N' here may make sense for embedded or server kernels. 2212 2213source "kernel/livepatch/Kconfig" 2214 2215endmenu 2216 2217config ARCH_ENABLE_MEMORY_HOTPLUG 2218 def_bool y 2219 depends on X86_64 || (X86_32 && HIGHMEM) 2220 2221config ARCH_ENABLE_MEMORY_HOTREMOVE 2222 def_bool y 2223 depends on MEMORY_HOTPLUG 2224 2225config USE_PERCPU_NUMA_NODE_ID 2226 def_bool y 2227 depends on NUMA 2228 2229config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2230 def_bool y 2231 depends on X86_64 || X86_PAE 2232 2233config ARCH_ENABLE_HUGEPAGE_MIGRATION 2234 def_bool y 2235 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2236 2237menu "Power management and ACPI options" 2238 2239config ARCH_HIBERNATION_HEADER 2240 def_bool y 2241 depends on X86_64 && HIBERNATION 2242 2243source "kernel/power/Kconfig" 2244 2245source "drivers/acpi/Kconfig" 2246 2247source "drivers/sfi/Kconfig" 2248 2249config X86_APM_BOOT 2250 def_bool y 2251 depends on APM 2252 2253menuconfig APM 2254 tristate "APM (Advanced Power Management) BIOS support" 2255 depends on X86_32 && PM_SLEEP 2256 ---help--- 2257 APM is a BIOS specification for saving power using several different 2258 techniques. This is mostly useful for battery powered laptops with 2259 APM compliant BIOSes. If you say Y here, the system time will be 2260 reset after a RESUME operation, the /proc/apm device will provide 2261 battery status information, and user-space programs will receive 2262 notification of APM "events" (e.g. battery status change). 2263 2264 If you select "Y" here, you can disable actual use of the APM 2265 BIOS by passing the "apm=off" option to the kernel at boot time. 2266 2267 Note that the APM support is almost completely disabled for 2268 machines with more than one CPU. 2269 2270 In order to use APM, you will need supporting software. For location 2271 and more information, read <file:Documentation/power/apm-acpi.txt> 2272 and the Battery Powered Linux mini-HOWTO, available from 2273 <http://www.tldp.org/docs.html#howto>. 2274 2275 This driver does not spin down disk drives (see the hdparm(8) 2276 manpage ("man 8 hdparm") for that), and it doesn't turn off 2277 VESA-compliant "green" monitors. 2278 2279 This driver does not support the TI 4000M TravelMate and the ACER 2280 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2281 desktop machines also don't have compliant BIOSes, and this driver 2282 may cause those machines to panic during the boot phase. 2283 2284 Generally, if you don't have a battery in your machine, there isn't 2285 much point in using this driver and you should say N. If you get 2286 random kernel OOPSes or reboots that don't seem to be related to 2287 anything, try disabling/enabling this option (or disabling/enabling 2288 APM in your BIOS). 2289 2290 Some other things you should try when experiencing seemingly random, 2291 "weird" problems: 2292 2293 1) make sure that you have enough swap space and that it is 2294 enabled. 2295 2) pass the "no-hlt" option to the kernel 2296 3) switch on floating point emulation in the kernel and pass 2297 the "no387" option to the kernel 2298 4) pass the "floppy=nodma" option to the kernel 2299 5) pass the "mem=4M" option to the kernel (thereby disabling 2300 all but the first 4 MB of RAM) 2301 6) make sure that the CPU is not over clocked. 2302 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2303 8) disable the cache from your BIOS settings 2304 9) install a fan for the video card or exchange video RAM 2305 10) install a better fan for the CPU 2306 11) exchange RAM chips 2307 12) exchange the motherboard. 2308 2309 To compile this driver as a module, choose M here: the 2310 module will be called apm. 2311 2312if APM 2313 2314config APM_IGNORE_USER_SUSPEND 2315 bool "Ignore USER SUSPEND" 2316 ---help--- 2317 This option will ignore USER SUSPEND requests. On machines with a 2318 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2319 series notebooks, it is necessary to say Y because of a BIOS bug. 2320 2321config APM_DO_ENABLE 2322 bool "Enable PM at boot time" 2323 ---help--- 2324 Enable APM features at boot time. From page 36 of the APM BIOS 2325 specification: "When disabled, the APM BIOS does not automatically 2326 power manage devices, enter the Standby State, enter the Suspend 2327 State, or take power saving steps in response to CPU Idle calls." 2328 This driver will make CPU Idle calls when Linux is idle (unless this 2329 feature is turned off -- see "Do CPU IDLE calls", below). This 2330 should always save battery power, but more complicated APM features 2331 will be dependent on your BIOS implementation. You may need to turn 2332 this option off if your computer hangs at boot time when using APM 2333 support, or if it beeps continuously instead of suspending. Turn 2334 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2335 T400CDT. This is off by default since most machines do fine without 2336 this feature. 2337 2338config APM_CPU_IDLE 2339 depends on CPU_IDLE 2340 bool "Make CPU Idle calls when idle" 2341 ---help--- 2342 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2343 On some machines, this can activate improved power savings, such as 2344 a slowed CPU clock rate, when the machine is idle. These idle calls 2345 are made after the idle loop has run for some length of time (e.g., 2346 333 mS). On some machines, this will cause a hang at boot time or 2347 whenever the CPU becomes idle. (On machines with more than one CPU, 2348 this option does nothing.) 2349 2350config APM_DISPLAY_BLANK 2351 bool "Enable console blanking using APM" 2352 ---help--- 2353 Enable console blanking using the APM. Some laptops can use this to 2354 turn off the LCD backlight when the screen blanker of the Linux 2355 virtual console blanks the screen. Note that this is only used by 2356 the virtual console screen blanker, and won't turn off the backlight 2357 when using the X Window system. This also doesn't have anything to 2358 do with your VESA-compliant power-saving monitor. Further, this 2359 option doesn't work for all laptops -- it might not turn off your 2360 backlight at all, or it might print a lot of errors to the console, 2361 especially if you are using gpm. 2362 2363config APM_ALLOW_INTS 2364 bool "Allow interrupts during APM BIOS calls" 2365 ---help--- 2366 Normally we disable external interrupts while we are making calls to 2367 the APM BIOS as a measure to lessen the effects of a badly behaving 2368 BIOS implementation. The BIOS should reenable interrupts if it 2369 needs to. Unfortunately, some BIOSes do not -- especially those in 2370 many of the newer IBM Thinkpads. If you experience hangs when you 2371 suspend, try setting this to Y. Otherwise, say N. 2372 2373endif # APM 2374 2375source "drivers/cpufreq/Kconfig" 2376 2377source "drivers/cpuidle/Kconfig" 2378 2379source "drivers/idle/Kconfig" 2380 2381endmenu 2382 2383 2384menu "Bus options (PCI etc.)" 2385 2386config PCI 2387 bool "PCI support" 2388 default y 2389 ---help--- 2390 Find out whether you have a PCI motherboard. PCI is the name of a 2391 bus system, i.e. the way the CPU talks to the other stuff inside 2392 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2393 VESA. If you have PCI, say Y, otherwise N. 2394 2395choice 2396 prompt "PCI access mode" 2397 depends on X86_32 && PCI 2398 default PCI_GOANY 2399 ---help--- 2400 On PCI systems, the BIOS can be used to detect the PCI devices and 2401 determine their configuration. However, some old PCI motherboards 2402 have BIOS bugs and may crash if this is done. Also, some embedded 2403 PCI-based systems don't have any BIOS at all. Linux can also try to 2404 detect the PCI hardware directly without using the BIOS. 2405 2406 With this option, you can specify how Linux should detect the 2407 PCI devices. If you choose "BIOS", the BIOS will be used, 2408 if you choose "Direct", the BIOS won't be used, and if you 2409 choose "MMConfig", then PCI Express MMCONFIG will be used. 2410 If you choose "Any", the kernel will try MMCONFIG, then the 2411 direct access method and falls back to the BIOS if that doesn't 2412 work. If unsure, go with the default, which is "Any". 2413 2414config PCI_GOBIOS 2415 bool "BIOS" 2416 2417config PCI_GOMMCONFIG 2418 bool "MMConfig" 2419 2420config PCI_GODIRECT 2421 bool "Direct" 2422 2423config PCI_GOOLPC 2424 bool "OLPC XO-1" 2425 depends on OLPC 2426 2427config PCI_GOANY 2428 bool "Any" 2429 2430endchoice 2431 2432config PCI_BIOS 2433 def_bool y 2434 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2435 2436# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2437config PCI_DIRECT 2438 def_bool y 2439 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2440 2441config PCI_MMCONFIG 2442 def_bool y 2443 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2444 2445config PCI_OLPC 2446 def_bool y 2447 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2448 2449config PCI_XEN 2450 def_bool y 2451 depends on PCI && XEN 2452 select SWIOTLB_XEN 2453 2454config PCI_DOMAINS 2455 def_bool y 2456 depends on PCI 2457 2458config PCI_MMCONFIG 2459 bool "Support mmconfig PCI config space access" 2460 depends on X86_64 && PCI && ACPI 2461 2462config PCI_CNB20LE_QUIRK 2463 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2464 depends on PCI 2465 help 2466 Read the PCI windows out of the CNB20LE host bridge. This allows 2467 PCI hotplug to work on systems with the CNB20LE chipset which do 2468 not have ACPI. 2469 2470 There's no public spec for this chipset, and this functionality 2471 is known to be incomplete. 2472 2473 You should say N unless you know you need this. 2474 2475source "drivers/pci/Kconfig" 2476 2477config ISA_BUS 2478 bool "ISA-style bus support on modern systems" if EXPERT 2479 select ISA_BUS_API 2480 help 2481 Enables ISA-style drivers on modern systems. This is necessary to 2482 support PC/104 devices on X86_64 platforms. 2483 2484 If unsure, say N. 2485 2486# x86_64 have no ISA slots, but can have ISA-style DMA. 2487config ISA_DMA_API 2488 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2489 default y 2490 help 2491 Enables ISA-style DMA support for devices requiring such controllers. 2492 If unsure, say Y. 2493 2494if X86_32 2495 2496config ISA 2497 bool "ISA support" 2498 ---help--- 2499 Find out whether you have ISA slots on your motherboard. ISA is the 2500 name of a bus system, i.e. the way the CPU talks to the other stuff 2501 inside your box. Other bus systems are PCI, EISA, MicroChannel 2502 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2503 newer boards don't support it. If you have ISA, say Y, otherwise N. 2504 2505config EISA 2506 bool "EISA support" 2507 depends on ISA 2508 ---help--- 2509 The Extended Industry Standard Architecture (EISA) bus was 2510 developed as an open alternative to the IBM MicroChannel bus. 2511 2512 The EISA bus provided some of the features of the IBM MicroChannel 2513 bus while maintaining backward compatibility with cards made for 2514 the older ISA bus. The EISA bus saw limited use between 1988 and 2515 1995 when it was made obsolete by the PCI bus. 2516 2517 Say Y here if you are building a kernel for an EISA-based machine. 2518 2519 Otherwise, say N. 2520 2521source "drivers/eisa/Kconfig" 2522 2523config SCx200 2524 tristate "NatSemi SCx200 support" 2525 ---help--- 2526 This provides basic support for National Semiconductor's 2527 (now AMD's) Geode processors. The driver probes for the 2528 PCI-IDs of several on-chip devices, so its a good dependency 2529 for other scx200_* drivers. 2530 2531 If compiled as a module, the driver is named scx200. 2532 2533config SCx200HR_TIMER 2534 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2535 depends on SCx200 2536 default y 2537 ---help--- 2538 This driver provides a clocksource built upon the on-chip 2539 27MHz high-resolution timer. Its also a workaround for 2540 NSC Geode SC-1100's buggy TSC, which loses time when the 2541 processor goes idle (as is done by the scheduler). The 2542 other workaround is idle=poll boot option. 2543 2544config OLPC 2545 bool "One Laptop Per Child support" 2546 depends on !X86_PAE 2547 select GPIOLIB 2548 select OF 2549 select OF_PROMTREE 2550 select IRQ_DOMAIN 2551 ---help--- 2552 Add support for detecting the unique features of the OLPC 2553 XO hardware. 2554 2555config OLPC_XO1_PM 2556 bool "OLPC XO-1 Power Management" 2557 depends on OLPC && MFD_CS5535 && PM_SLEEP 2558 select MFD_CORE 2559 ---help--- 2560 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2561 2562config OLPC_XO1_RTC 2563 bool "OLPC XO-1 Real Time Clock" 2564 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2565 ---help--- 2566 Add support for the XO-1 real time clock, which can be used as a 2567 programmable wakeup source. 2568 2569config OLPC_XO1_SCI 2570 bool "OLPC XO-1 SCI extras" 2571 depends on OLPC && OLPC_XO1_PM 2572 depends on INPUT=y 2573 select POWER_SUPPLY 2574 select GPIO_CS5535 2575 select MFD_CORE 2576 ---help--- 2577 Add support for SCI-based features of the OLPC XO-1 laptop: 2578 - EC-driven system wakeups 2579 - Power button 2580 - Ebook switch 2581 - Lid switch 2582 - AC adapter status updates 2583 - Battery status updates 2584 2585config OLPC_XO15_SCI 2586 bool "OLPC XO-1.5 SCI extras" 2587 depends on OLPC && ACPI 2588 select POWER_SUPPLY 2589 ---help--- 2590 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2591 - EC-driven system wakeups 2592 - AC adapter status updates 2593 - Battery status updates 2594 2595config ALIX 2596 bool "PCEngines ALIX System Support (LED setup)" 2597 select GPIOLIB 2598 ---help--- 2599 This option enables system support for the PCEngines ALIX. 2600 At present this just sets up LEDs for GPIO control on 2601 ALIX2/3/6 boards. However, other system specific setup should 2602 get added here. 2603 2604 Note: You must still enable the drivers for GPIO and LED support 2605 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2606 2607 Note: You have to set alix.force=1 for boards with Award BIOS. 2608 2609config NET5501 2610 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2611 select GPIOLIB 2612 ---help--- 2613 This option enables system support for the Soekris Engineering net5501. 2614 2615config GEOS 2616 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2617 select GPIOLIB 2618 depends on DMI 2619 ---help--- 2620 This option enables system support for the Traverse Technologies GEOS. 2621 2622config TS5500 2623 bool "Technologic Systems TS-5500 platform support" 2624 depends on MELAN 2625 select CHECK_SIGNATURE 2626 select NEW_LEDS 2627 select LEDS_CLASS 2628 ---help--- 2629 This option enables system support for the Technologic Systems TS-5500. 2630 2631endif # X86_32 2632 2633config AMD_NB 2634 def_bool y 2635 depends on CPU_SUP_AMD && PCI 2636 2637source "drivers/pcmcia/Kconfig" 2638 2639config RAPIDIO 2640 tristate "RapidIO support" 2641 depends on PCI 2642 default n 2643 help 2644 If enabled this option will include drivers and the core 2645 infrastructure code to support RapidIO interconnect devices. 2646 2647source "drivers/rapidio/Kconfig" 2648 2649config X86_SYSFB 2650 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2651 help 2652 Firmwares often provide initial graphics framebuffers so the BIOS, 2653 bootloader or kernel can show basic video-output during boot for 2654 user-guidance and debugging. Historically, x86 used the VESA BIOS 2655 Extensions and EFI-framebuffers for this, which are mostly limited 2656 to x86. 2657 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2658 framebuffers so the new generic system-framebuffer drivers can be 2659 used on x86. If the framebuffer is not compatible with the generic 2660 modes, it is adverticed as fallback platform framebuffer so legacy 2661 drivers like efifb, vesafb and uvesafb can pick it up. 2662 If this option is not selected, all system framebuffers are always 2663 marked as fallback platform framebuffers as usual. 2664 2665 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2666 not be able to pick up generic system framebuffers if this option 2667 is selected. You are highly encouraged to enable simplefb as 2668 replacement if you select this option. simplefb can correctly deal 2669 with generic system framebuffers. But you should still keep vesafb 2670 and others enabled as fallback if a system framebuffer is 2671 incompatible with simplefb. 2672 2673 If unsure, say Y. 2674 2675endmenu 2676 2677 2678menu "Executable file formats / Emulations" 2679 2680source "fs/Kconfig.binfmt" 2681 2682config IA32_EMULATION 2683 bool "IA32 Emulation" 2684 depends on X86_64 2685 select BINFMT_ELF 2686 select COMPAT_BINFMT_ELF 2687 select ARCH_WANT_OLD_COMPAT_IPC 2688 ---help--- 2689 Include code to run legacy 32-bit programs under a 2690 64-bit kernel. You should likely turn this on, unless you're 2691 100% sure that you don't have any 32-bit programs left. 2692 2693config IA32_AOUT 2694 tristate "IA32 a.out support" 2695 depends on IA32_EMULATION 2696 ---help--- 2697 Support old a.out binaries in the 32bit emulation. 2698 2699config X86_X32 2700 bool "x32 ABI for 64-bit mode" 2701 depends on X86_64 2702 ---help--- 2703 Include code to run binaries for the x32 native 32-bit ABI 2704 for 64-bit processors. An x32 process gets access to the 2705 full 64-bit register file and wide data path while leaving 2706 pointers at 32 bits for smaller memory footprint. 2707 2708 You will need a recent binutils (2.22 or later) with 2709 elf32_x86_64 support enabled to compile a kernel with this 2710 option set. 2711 2712config COMPAT 2713 def_bool y 2714 depends on IA32_EMULATION || X86_X32 2715 2716if COMPAT 2717config COMPAT_FOR_U64_ALIGNMENT 2718 def_bool y 2719 2720config SYSVIPC_COMPAT 2721 def_bool y 2722 depends on SYSVIPC 2723 2724config KEYS_COMPAT 2725 def_bool y 2726 depends on KEYS 2727endif 2728 2729endmenu 2730 2731 2732config HAVE_ATOMIC_IOMAP 2733 def_bool y 2734 depends on X86_32 2735 2736config X86_DEV_DMA_OPS 2737 bool 2738 depends on X86_64 || STA2X11 2739 2740config X86_DMA_REMAP 2741 bool 2742 depends on STA2X11 2743 2744config PMC_ATOM 2745 def_bool y 2746 depends on PCI 2747 2748config VMD 2749 depends on PCI_MSI 2750 tristate "Volume Management Device Driver" 2751 default N 2752 ---help--- 2753 Adds support for the Intel Volume Management Device (VMD). VMD is a 2754 secondary PCI host bridge that allows PCI Express root ports, 2755 and devices attached to them, to be removed from the default 2756 PCI domain and placed within the VMD domain. This provides 2757 more bus resources than are otherwise possible with a 2758 single domain. If you know your system provides one of these and 2759 has devices attached to it, say Y; if you are not sure, say N. 2760 2761source "net/Kconfig" 2762 2763source "drivers/Kconfig" 2764 2765source "drivers/firmware/Kconfig" 2766 2767source "fs/Kconfig" 2768 2769source "arch/x86/Kconfig.debug" 2770 2771source "security/Kconfig" 2772 2773source "crypto/Kconfig" 2774 2775source "arch/x86/kvm/Kconfig" 2776 2777source "lib/Kconfig" 2778