1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH != "i386" 5 ---help--- 6 Say yes to build a 64-bit kernel - formerly known as x86_64 7 Say no to build a 32-bit kernel - formerly known as i386 8 9config X86_32 10 def_bool y 11 depends on !64BIT 12 13config X86_64 14 def_bool y 15 depends on 64BIT 16 17### Arch settings 18config X86 19 def_bool y 20 select ACPI_LEGACY_TABLES_LOOKUP if ACPI 21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 22 select ANON_INODES 23 select ARCH_CLOCKSOURCE_DATA 24 select ARCH_DISCARD_MEMBLOCK 25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 27 select ARCH_HAS_ELF_RANDOMIZE 28 select ARCH_HAS_FAST_MULTIPLIER 29 select ARCH_HAS_GCOV_PROFILE_ALL 30 select ARCH_HAS_PMEM_API if X86_64 31 select ARCH_HAS_MMIO_FLUSH 32 select ARCH_HAS_SG_CHAIN 33 select ARCH_HAVE_NMI_SAFE_CMPXCHG 34 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 35 select ARCH_MIGHT_HAVE_PC_PARPORT 36 select ARCH_MIGHT_HAVE_PC_SERIO 37 select ARCH_SUPPORTS_ATOMIC_RMW 38 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 39 select ARCH_SUPPORTS_INT128 if X86_64 40 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 41 select ARCH_USE_BUILTIN_BSWAP 42 select ARCH_USE_CMPXCHG_LOCKREF if X86_64 43 select ARCH_USE_QUEUED_RWLOCKS 44 select ARCH_USE_QUEUED_SPINLOCKS 45 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 46 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 47 select ARCH_WANT_FRAME_POINTERS 48 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 49 select ARCH_WANT_OPTIONAL_GPIOLIB 50 select BUILDTIME_EXTABLE_SORT 51 select CLKEVT_I8253 52 select CLKSRC_I8253 if X86_32 53 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 54 select CLOCKSOURCE_WATCHDOG 55 select CLONE_BACKWARDS if X86_32 56 select COMPAT_OLD_SIGACTION if IA32_EMULATION 57 select DCACHE_WORD_ACCESS 58 select EDAC_ATOMIC_SCRUB 59 select EDAC_SUPPORT 60 select GENERIC_CLOCKEVENTS 61 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 62 select GENERIC_CLOCKEVENTS_MIN_ADJUST 63 select GENERIC_CMOS_UPDATE 64 select GENERIC_CPU_AUTOPROBE 65 select GENERIC_EARLY_IOREMAP 66 select GENERIC_FIND_FIRST_BIT 67 select GENERIC_IOMAP 68 select GENERIC_IRQ_PROBE 69 select GENERIC_IRQ_SHOW 70 select GENERIC_PENDING_IRQ if SMP 71 select GENERIC_SMP_IDLE_THREAD 72 select GENERIC_STRNCPY_FROM_USER 73 select GENERIC_STRNLEN_USER 74 select GENERIC_TIME_VSYSCALL 75 select HAVE_ACPI_APEI if ACPI 76 select HAVE_ACPI_APEI_NMI if ACPI 77 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 78 select HAVE_AOUT if X86_32 79 select HAVE_ARCH_AUDITSYSCALL 80 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 81 select HAVE_ARCH_JUMP_LABEL 82 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 83 select HAVE_ARCH_KGDB 84 select HAVE_ARCH_KMEMCHECK 85 select HAVE_ARCH_SECCOMP_FILTER 86 select HAVE_ARCH_SOFT_DIRTY if X86_64 87 select HAVE_ARCH_TRACEHOOK 88 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 89 select HAVE_BPF_JIT if X86_64 90 select HAVE_CC_STACKPROTECTOR 91 select HAVE_CMPXCHG_DOUBLE 92 select HAVE_CMPXCHG_LOCAL 93 select HAVE_CONTEXT_TRACKING if X86_64 94 select HAVE_COPY_THREAD_TLS 95 select HAVE_C_RECORDMCOUNT 96 select HAVE_DEBUG_KMEMLEAK 97 select HAVE_DEBUG_STACKOVERFLOW 98 select HAVE_DMA_API_DEBUG 99 select HAVE_DMA_ATTRS 100 select HAVE_DMA_CONTIGUOUS 101 select HAVE_DYNAMIC_FTRACE 102 select HAVE_DYNAMIC_FTRACE_WITH_REGS 103 select HAVE_EFFICIENT_UNALIGNED_ACCESS 104 select HAVE_FENTRY if X86_64 105 select HAVE_FTRACE_MCOUNT_RECORD 106 select HAVE_FUNCTION_GRAPH_FP_TEST 107 select HAVE_FUNCTION_GRAPH_TRACER 108 select HAVE_FUNCTION_TRACER 109 select HAVE_GENERIC_DMA_COHERENT if X86_32 110 select HAVE_HW_BREAKPOINT 111 select HAVE_IDE 112 select HAVE_IOREMAP_PROT 113 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 114 select HAVE_IRQ_TIME_ACCOUNTING 115 select HAVE_KERNEL_BZIP2 116 select HAVE_KERNEL_GZIP 117 select HAVE_KERNEL_LZ4 118 select HAVE_KERNEL_LZMA 119 select HAVE_KERNEL_LZO 120 select HAVE_KERNEL_XZ 121 select HAVE_KPROBES 122 select HAVE_KPROBES_ON_FTRACE 123 select HAVE_KRETPROBES 124 select HAVE_KVM 125 select HAVE_LIVEPATCH if X86_64 126 select HAVE_MEMBLOCK 127 select HAVE_MEMBLOCK_NODE_MAP 128 select HAVE_MIXED_BREAKPOINTS_REGS 129 select HAVE_OPROFILE 130 select HAVE_OPTPROBES 131 select HAVE_PCSPKR_PLATFORM 132 select HAVE_PERF_EVENTS 133 select HAVE_PERF_EVENTS_NMI 134 select HAVE_PERF_REGS 135 select HAVE_PERF_USER_STACK_DUMP 136 select HAVE_REGS_AND_STACK_ACCESS_API 137 select HAVE_SYSCALL_TRACEPOINTS 138 select HAVE_UID16 if X86_32 || IA32_EMULATION 139 select HAVE_UNSTABLE_SCHED_CLOCK 140 select HAVE_USER_RETURN_NOTIFIER 141 select IRQ_FORCED_THREADING 142 select MODULES_USE_ELF_RELA if X86_64 143 select MODULES_USE_ELF_REL if X86_32 144 select OLD_SIGACTION if X86_32 145 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 146 select PERF_EVENTS 147 select RTC_LIB 148 select SPARSE_IRQ 149 select SRCU 150 select SYSCTL_EXCEPTION_TRACE 151 select USER_STACKTRACE_SUPPORT 152 select VIRT_TO_BUS 153 select X86_DEV_DMA_OPS if X86_64 154 select X86_FEATURE_NAMES if PROC_FS 155 156config INSTRUCTION_DECODER 157 def_bool y 158 depends on KPROBES || PERF_EVENTS || UPROBES 159 160config PERF_EVENTS_INTEL_UNCORE 161 def_bool y 162 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI 163 164config OUTPUT_FORMAT 165 string 166 default "elf32-i386" if X86_32 167 default "elf64-x86-64" if X86_64 168 169config ARCH_DEFCONFIG 170 string 171 default "arch/x86/configs/i386_defconfig" if X86_32 172 default "arch/x86/configs/x86_64_defconfig" if X86_64 173 174config LOCKDEP_SUPPORT 175 def_bool y 176 177config STACKTRACE_SUPPORT 178 def_bool y 179 180config HAVE_LATENCYTOP_SUPPORT 181 def_bool y 182 183config MMU 184 def_bool y 185 186config SBUS 187 bool 188 189config NEED_DMA_MAP_STATE 190 def_bool y 191 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 192 193config NEED_SG_DMA_LENGTH 194 def_bool y 195 196config GENERIC_ISA_DMA 197 def_bool y 198 depends on ISA_DMA_API 199 200config GENERIC_BUG 201 def_bool y 202 depends on BUG 203 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 204 205config GENERIC_BUG_RELATIVE_POINTERS 206 bool 207 208config GENERIC_HWEIGHT 209 def_bool y 210 211config ARCH_MAY_HAVE_PC_FDC 212 def_bool y 213 depends on ISA_DMA_API 214 215config RWSEM_XCHGADD_ALGORITHM 216 def_bool y 217 218config GENERIC_CALIBRATE_DELAY 219 def_bool y 220 221config ARCH_HAS_CPU_RELAX 222 def_bool y 223 224config ARCH_HAS_CACHE_LINE_SIZE 225 def_bool y 226 227config HAVE_SETUP_PER_CPU_AREA 228 def_bool y 229 230config NEED_PER_CPU_EMBED_FIRST_CHUNK 231 def_bool y 232 233config NEED_PER_CPU_PAGE_FIRST_CHUNK 234 def_bool y 235 236config ARCH_HIBERNATION_POSSIBLE 237 def_bool y 238 239config ARCH_SUSPEND_POSSIBLE 240 def_bool y 241 242config ARCH_WANT_HUGE_PMD_SHARE 243 def_bool y 244 245config ARCH_WANT_GENERAL_HUGETLB 246 def_bool y 247 248config ZONE_DMA32 249 def_bool y if X86_64 250 251config AUDIT_ARCH 252 def_bool y if X86_64 253 254config ARCH_SUPPORTS_OPTIMIZED_INLINING 255 def_bool y 256 257config ARCH_SUPPORTS_DEBUG_PAGEALLOC 258 def_bool y 259 260config KASAN_SHADOW_OFFSET 261 hex 262 depends on KASAN 263 default 0xdffffc0000000000 264 265config HAVE_INTEL_TXT 266 def_bool y 267 depends on INTEL_IOMMU && ACPI 268 269config X86_32_SMP 270 def_bool y 271 depends on X86_32 && SMP 272 273config X86_64_SMP 274 def_bool y 275 depends on X86_64 && SMP 276 277config X86_32_LAZY_GS 278 def_bool y 279 depends on X86_32 && !CC_STACKPROTECTOR 280 281config ARCH_HWEIGHT_CFLAGS 282 string 283 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 284 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 285 286config ARCH_SUPPORTS_UPROBES 287 def_bool y 288 289config FIX_EARLYCON_MEM 290 def_bool y 291 292config PGTABLE_LEVELS 293 int 294 default 4 if X86_64 295 default 3 if X86_PAE 296 default 2 297 298source "init/Kconfig" 299source "kernel/Kconfig.freezer" 300 301menu "Processor type and features" 302 303config ZONE_DMA 304 bool "DMA memory allocation support" if EXPERT 305 default y 306 help 307 DMA memory allocation support allows devices with less than 32-bit 308 addressing to allocate within the first 16MB of address space. 309 Disable if no such devices will be used. 310 311 If unsure, say Y. 312 313config SMP 314 bool "Symmetric multi-processing support" 315 ---help--- 316 This enables support for systems with more than one CPU. If you have 317 a system with only one CPU, say N. If you have a system with more 318 than one CPU, say Y. 319 320 If you say N here, the kernel will run on uni- and multiprocessor 321 machines, but will use only one CPU of a multiprocessor machine. If 322 you say Y here, the kernel will run on many, but not all, 323 uniprocessor machines. On a uniprocessor machine, the kernel 324 will run faster if you say N here. 325 326 Note that if you say Y here and choose architecture "586" or 327 "Pentium" under "Processor family", the kernel will not work on 486 328 architectures. Similarly, multiprocessor kernels for the "PPro" 329 architecture may not work on all Pentium based boards. 330 331 People using multiprocessor machines who say Y here should also say 332 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 333 Management" code will be disabled if you say Y here. 334 335 See also <file:Documentation/x86/i386/IO-APIC.txt>, 336 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 337 <http://www.tldp.org/docs.html#howto>. 338 339 If you don't know what to do here, say N. 340 341config X86_FEATURE_NAMES 342 bool "Processor feature human-readable names" if EMBEDDED 343 default y 344 ---help--- 345 This option compiles in a table of x86 feature bits and corresponding 346 names. This is required to support /proc/cpuinfo and a few kernel 347 messages. You can disable this to save space, at the expense of 348 making those few kernel messages show numeric feature bits instead. 349 350 If in doubt, say Y. 351 352config X86_X2APIC 353 bool "Support x2apic" 354 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 355 ---help--- 356 This enables x2apic support on CPUs that have this feature. 357 358 This allows 32-bit apic IDs (so it can support very large systems), 359 and accesses the local apic via MSRs not via mmio. 360 361 If you don't know what to do here, say N. 362 363config X86_MPPARSE 364 bool "Enable MPS table" if ACPI || SFI 365 default y 366 depends on X86_LOCAL_APIC 367 ---help--- 368 For old smp systems that do not have proper acpi support. Newer systems 369 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 370 371config X86_BIGSMP 372 bool "Support for big SMP systems with more than 8 CPUs" 373 depends on X86_32 && SMP 374 ---help--- 375 This option is needed for the systems that have more than 8 CPUs 376 377config GOLDFISH 378 def_bool y 379 depends on X86_GOLDFISH 380 381if X86_32 382config X86_EXTENDED_PLATFORM 383 bool "Support for extended (non-PC) x86 platforms" 384 default y 385 ---help--- 386 If you disable this option then the kernel will only support 387 standard PC platforms. (which covers the vast majority of 388 systems out there.) 389 390 If you enable this option then you'll be able to select support 391 for the following (non-PC) 32 bit x86 platforms: 392 Goldfish (Android emulator) 393 AMD Elan 394 RDC R-321x SoC 395 SGI 320/540 (Visual Workstation) 396 STA2X11-based (e.g. Northville) 397 Moorestown MID devices 398 399 If you have one of these systems, or if you want to build a 400 generic distribution kernel, say Y here - otherwise say N. 401endif 402 403if X86_64 404config X86_EXTENDED_PLATFORM 405 bool "Support for extended (non-PC) x86 platforms" 406 default y 407 ---help--- 408 If you disable this option then the kernel will only support 409 standard PC platforms. (which covers the vast majority of 410 systems out there.) 411 412 If you enable this option then you'll be able to select support 413 for the following (non-PC) 64 bit x86 platforms: 414 Numascale NumaChip 415 ScaleMP vSMP 416 SGI Ultraviolet 417 418 If you have one of these systems, or if you want to build a 419 generic distribution kernel, say Y here - otherwise say N. 420endif 421# This is an alphabetically sorted list of 64 bit extended platforms 422# Please maintain the alphabetic order if and when there are additions 423config X86_NUMACHIP 424 bool "Numascale NumaChip" 425 depends on X86_64 426 depends on X86_EXTENDED_PLATFORM 427 depends on NUMA 428 depends on SMP 429 depends on X86_X2APIC 430 depends on PCI_MMCONFIG 431 ---help--- 432 Adds support for Numascale NumaChip large-SMP systems. Needed to 433 enable more than ~168 cores. 434 If you don't have one of these, you should say N here. 435 436config X86_VSMP 437 bool "ScaleMP vSMP" 438 select HYPERVISOR_GUEST 439 select PARAVIRT 440 depends on X86_64 && PCI 441 depends on X86_EXTENDED_PLATFORM 442 depends on SMP 443 ---help--- 444 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 445 supposed to run on these EM64T-based machines. Only choose this option 446 if you have one of these machines. 447 448config X86_UV 449 bool "SGI Ultraviolet" 450 depends on X86_64 451 depends on X86_EXTENDED_PLATFORM 452 depends on NUMA 453 depends on X86_X2APIC 454 depends on PCI 455 ---help--- 456 This option is needed in order to support SGI Ultraviolet systems. 457 If you don't have one of these, you should say N here. 458 459# Following is an alphabetically sorted list of 32 bit extended platforms 460# Please maintain the alphabetic order if and when there are additions 461 462config X86_GOLDFISH 463 bool "Goldfish (Virtual Platform)" 464 depends on X86_EXTENDED_PLATFORM 465 ---help--- 466 Enable support for the Goldfish virtual platform used primarily 467 for Android development. Unless you are building for the Android 468 Goldfish emulator say N here. 469 470config X86_INTEL_CE 471 bool "CE4100 TV platform" 472 depends on PCI 473 depends on PCI_GODIRECT 474 depends on X86_IO_APIC 475 depends on X86_32 476 depends on X86_EXTENDED_PLATFORM 477 select X86_REBOOTFIXUPS 478 select OF 479 select OF_EARLY_FLATTREE 480 ---help--- 481 Select for the Intel CE media processor (CE4100) SOC. 482 This option compiles in support for the CE4100 SOC for settop 483 boxes and media devices. 484 485config X86_INTEL_MID 486 bool "Intel MID platform support" 487 depends on X86_32 488 depends on X86_EXTENDED_PLATFORM 489 depends on X86_PLATFORM_DEVICES 490 depends on PCI 491 depends on PCI_GOANY 492 depends on X86_IO_APIC 493 select SFI 494 select I2C 495 select DW_APB_TIMER 496 select APB_TIMER 497 select INTEL_SCU_IPC 498 select MFD_INTEL_MSIC 499 ---help--- 500 Select to build a kernel capable of supporting Intel MID (Mobile 501 Internet Device) platform systems which do not have the PCI legacy 502 interfaces. If you are building for a PC class system say N here. 503 504 Intel MID platforms are based on an Intel processor and chipset which 505 consume less power than most of the x86 derivatives. 506 507config X86_INTEL_QUARK 508 bool "Intel Quark platform support" 509 depends on X86_32 510 depends on X86_EXTENDED_PLATFORM 511 depends on X86_PLATFORM_DEVICES 512 depends on X86_TSC 513 depends on PCI 514 depends on PCI_GOANY 515 depends on X86_IO_APIC 516 select IOSF_MBI 517 select INTEL_IMR 518 select COMMON_CLK 519 ---help--- 520 Select to include support for Quark X1000 SoC. 521 Say Y here if you have a Quark based system such as the Arduino 522 compatible Intel Galileo. 523 524config X86_INTEL_LPSS 525 bool "Intel Low Power Subsystem Support" 526 depends on ACPI 527 select COMMON_CLK 528 select PINCTRL 529 ---help--- 530 Select to build support for Intel Low Power Subsystem such as 531 found on Intel Lynxpoint PCH. Selecting this option enables 532 things like clock tree (common clock framework) and pincontrol 533 which are needed by the LPSS peripheral drivers. 534 535config X86_AMD_PLATFORM_DEVICE 536 bool "AMD ACPI2Platform devices support" 537 depends on ACPI 538 select COMMON_CLK 539 select PINCTRL 540 ---help--- 541 Select to interpret AMD specific ACPI device to platform device 542 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 543 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 544 implemented under PINCTRL subsystem. 545 546config IOSF_MBI 547 tristate "Intel SoC IOSF Sideband support for SoC platforms" 548 depends on PCI 549 ---help--- 550 This option enables sideband register access support for Intel SoC 551 platforms. On these platforms the IOSF sideband is used in lieu of 552 MSR's for some register accesses, mostly but not limited to thermal 553 and power. Drivers may query the availability of this device to 554 determine if they need the sideband in order to work on these 555 platforms. The sideband is available on the following SoC products. 556 This list is not meant to be exclusive. 557 - BayTrail 558 - Braswell 559 - Quark 560 561 You should say Y if you are running a kernel on one of these SoC's. 562 563config IOSF_MBI_DEBUG 564 bool "Enable IOSF sideband access through debugfs" 565 depends on IOSF_MBI && DEBUG_FS 566 ---help--- 567 Select this option to expose the IOSF sideband access registers (MCR, 568 MDR, MCRX) through debugfs to write and read register information from 569 different units on the SoC. This is most useful for obtaining device 570 state information for debug and analysis. As this is a general access 571 mechanism, users of this option would have specific knowledge of the 572 device they want to access. 573 574 If you don't require the option or are in doubt, say N. 575 576config X86_RDC321X 577 bool "RDC R-321x SoC" 578 depends on X86_32 579 depends on X86_EXTENDED_PLATFORM 580 select M486 581 select X86_REBOOTFIXUPS 582 ---help--- 583 This option is needed for RDC R-321x system-on-chip, also known 584 as R-8610-(G). 585 If you don't have one of these chips, you should say N here. 586 587config X86_32_NON_STANDARD 588 bool "Support non-standard 32-bit SMP architectures" 589 depends on X86_32 && SMP 590 depends on X86_EXTENDED_PLATFORM 591 ---help--- 592 This option compiles in the bigsmp and STA2X11 default 593 subarchitectures. It is intended for a generic binary 594 kernel. If you select them all, kernel will probe it one by 595 one and will fallback to default. 596 597# Alphabetically sorted list of Non standard 32 bit platforms 598 599config X86_SUPPORTS_MEMORY_FAILURE 600 def_bool y 601 # MCE code calls memory_failure(): 602 depends on X86_MCE 603 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 604 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 605 depends on X86_64 || !SPARSEMEM 606 select ARCH_SUPPORTS_MEMORY_FAILURE 607 608config STA2X11 609 bool "STA2X11 Companion Chip Support" 610 depends on X86_32_NON_STANDARD && PCI 611 select X86_DEV_DMA_OPS 612 select X86_DMA_REMAP 613 select SWIOTLB 614 select MFD_STA2X11 615 select ARCH_REQUIRE_GPIOLIB 616 default n 617 ---help--- 618 This adds support for boards based on the STA2X11 IO-Hub, 619 a.k.a. "ConneXt". The chip is used in place of the standard 620 PC chipset, so all "standard" peripherals are missing. If this 621 option is selected the kernel will still be able to boot on 622 standard PC machines. 623 624config X86_32_IRIS 625 tristate "Eurobraille/Iris poweroff module" 626 depends on X86_32 627 ---help--- 628 The Iris machines from EuroBraille do not have APM or ACPI support 629 to shut themselves down properly. A special I/O sequence is 630 needed to do so, which is what this module does at 631 kernel shutdown. 632 633 This is only for Iris machines from EuroBraille. 634 635 If unused, say N. 636 637config SCHED_OMIT_FRAME_POINTER 638 def_bool y 639 prompt "Single-depth WCHAN output" 640 depends on X86 641 ---help--- 642 Calculate simpler /proc/<PID>/wchan values. If this option 643 is disabled then wchan values will recurse back to the 644 caller function. This provides more accurate wchan values, 645 at the expense of slightly more scheduling overhead. 646 647 If in doubt, say "Y". 648 649menuconfig HYPERVISOR_GUEST 650 bool "Linux guest support" 651 ---help--- 652 Say Y here to enable options for running Linux under various hyper- 653 visors. This option enables basic hypervisor detection and platform 654 setup. 655 656 If you say N, all options in this submenu will be skipped and 657 disabled, and Linux guest support won't be built in. 658 659if HYPERVISOR_GUEST 660 661config PARAVIRT 662 bool "Enable paravirtualization code" 663 ---help--- 664 This changes the kernel so it can modify itself when it is run 665 under a hypervisor, potentially improving performance significantly 666 over full virtualization. However, when run without a hypervisor 667 the kernel is theoretically slower and slightly larger. 668 669config PARAVIRT_DEBUG 670 bool "paravirt-ops debugging" 671 depends on PARAVIRT && DEBUG_KERNEL 672 ---help--- 673 Enable to debug paravirt_ops internals. Specifically, BUG if 674 a paravirt_op is missing when it is called. 675 676config PARAVIRT_SPINLOCKS 677 bool "Paravirtualization layer for spinlocks" 678 depends on PARAVIRT && SMP 679 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS 680 ---help--- 681 Paravirtualized spinlocks allow a pvops backend to replace the 682 spinlock implementation with something virtualization-friendly 683 (for example, block the virtual CPU rather than spinning). 684 685 It has a minimal impact on native kernels and gives a nice performance 686 benefit on paravirtualized KVM / Xen kernels. 687 688 If you are unsure how to answer this question, answer Y. 689 690source "arch/x86/xen/Kconfig" 691 692config KVM_GUEST 693 bool "KVM Guest support (including kvmclock)" 694 depends on PARAVIRT 695 select PARAVIRT_CLOCK 696 default y 697 ---help--- 698 This option enables various optimizations for running under the KVM 699 hypervisor. It includes a paravirtualized clock, so that instead 700 of relying on a PIT (or probably other) emulation by the 701 underlying device model, the host provides the guest with 702 timing infrastructure such as time of day, and system time 703 704config KVM_DEBUG_FS 705 bool "Enable debug information for KVM Guests in debugfs" 706 depends on KVM_GUEST && DEBUG_FS 707 default n 708 ---help--- 709 This option enables collection of various statistics for KVM guest. 710 Statistics are displayed in debugfs filesystem. Enabling this option 711 may incur significant overhead. 712 713source "arch/x86/lguest/Kconfig" 714 715config PARAVIRT_TIME_ACCOUNTING 716 bool "Paravirtual steal time accounting" 717 depends on PARAVIRT 718 default n 719 ---help--- 720 Select this option to enable fine granularity task steal time 721 accounting. Time spent executing other tasks in parallel with 722 the current vCPU is discounted from the vCPU power. To account for 723 that, there can be a small performance impact. 724 725 If in doubt, say N here. 726 727config PARAVIRT_CLOCK 728 bool 729 730endif #HYPERVISOR_GUEST 731 732config NO_BOOTMEM 733 def_bool y 734 735source "arch/x86/Kconfig.cpu" 736 737config HPET_TIMER 738 def_bool X86_64 739 prompt "HPET Timer Support" if X86_32 740 ---help--- 741 Use the IA-PC HPET (High Precision Event Timer) to manage 742 time in preference to the PIT and RTC, if a HPET is 743 present. 744 HPET is the next generation timer replacing legacy 8254s. 745 The HPET provides a stable time base on SMP 746 systems, unlike the TSC, but it is more expensive to access, 747 as it is off-chip. You can find the HPET spec at 748 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 749 750 You can safely choose Y here. However, HPET will only be 751 activated if the platform and the BIOS support this feature. 752 Otherwise the 8254 will be used for timing services. 753 754 Choose N to continue using the legacy 8254 timer. 755 756config HPET_EMULATE_RTC 757 def_bool y 758 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 759 760config APB_TIMER 761 def_bool y if X86_INTEL_MID 762 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 763 select DW_APB_TIMER 764 depends on X86_INTEL_MID && SFI 765 help 766 APB timer is the replacement for 8254, HPET on X86 MID platforms. 767 The APBT provides a stable time base on SMP 768 systems, unlike the TSC, but it is more expensive to access, 769 as it is off-chip. APB timers are always running regardless of CPU 770 C states, they are used as per CPU clockevent device when possible. 771 772# Mark as expert because too many people got it wrong. 773# The code disables itself when not needed. 774config DMI 775 default y 776 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 777 bool "Enable DMI scanning" if EXPERT 778 ---help--- 779 Enabled scanning of DMI to identify machine quirks. Say Y 780 here unless you have verified that your setup is not 781 affected by entries in the DMI blacklist. Required by PNP 782 BIOS code. 783 784config GART_IOMMU 785 bool "Old AMD GART IOMMU support" 786 select SWIOTLB 787 depends on X86_64 && PCI && AMD_NB 788 ---help--- 789 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 790 GART based hardware IOMMUs. 791 792 The GART supports full DMA access for devices with 32-bit access 793 limitations, on systems with more than 3 GB. This is usually needed 794 for USB, sound, many IDE/SATA chipsets and some other devices. 795 796 Newer systems typically have a modern AMD IOMMU, supported via 797 the CONFIG_AMD_IOMMU=y config option. 798 799 In normal configurations this driver is only active when needed: 800 there's more than 3 GB of memory and the system contains a 801 32-bit limited device. 802 803 If unsure, say Y. 804 805config CALGARY_IOMMU 806 bool "IBM Calgary IOMMU support" 807 select SWIOTLB 808 depends on X86_64 && PCI 809 ---help--- 810 Support for hardware IOMMUs in IBM's xSeries x366 and x460 811 systems. Needed to run systems with more than 3GB of memory 812 properly with 32-bit PCI devices that do not support DAC 813 (Double Address Cycle). Calgary also supports bus level 814 isolation, where all DMAs pass through the IOMMU. This 815 prevents them from going anywhere except their intended 816 destination. This catches hard-to-find kernel bugs and 817 mis-behaving drivers and devices that do not use the DMA-API 818 properly to set up their DMA buffers. The IOMMU can be 819 turned off at boot time with the iommu=off parameter. 820 Normally the kernel will make the right choice by itself. 821 If unsure, say Y. 822 823config CALGARY_IOMMU_ENABLED_BY_DEFAULT 824 def_bool y 825 prompt "Should Calgary be enabled by default?" 826 depends on CALGARY_IOMMU 827 ---help--- 828 Should Calgary be enabled by default? if you choose 'y', Calgary 829 will be used (if it exists). If you choose 'n', Calgary will not be 830 used even if it exists. If you choose 'n' and would like to use 831 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 832 If unsure, say Y. 833 834# need this always selected by IOMMU for the VIA workaround 835config SWIOTLB 836 def_bool y if X86_64 837 ---help--- 838 Support for software bounce buffers used on x86-64 systems 839 which don't have a hardware IOMMU. Using this PCI devices 840 which can only access 32-bits of memory can be used on systems 841 with more than 3 GB of memory. 842 If unsure, say Y. 843 844config IOMMU_HELPER 845 def_bool y 846 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 847 848config MAXSMP 849 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 850 depends on X86_64 && SMP && DEBUG_KERNEL 851 select CPUMASK_OFFSTACK 852 ---help--- 853 Enable maximum number of CPUS and NUMA Nodes for this architecture. 854 If unsure, say N. 855 856config NR_CPUS 857 int "Maximum number of CPUs" if SMP && !MAXSMP 858 range 2 8 if SMP && X86_32 && !X86_BIGSMP 859 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 860 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 861 default "1" if !SMP 862 default "8192" if MAXSMP 863 default "32" if SMP && X86_BIGSMP 864 default "8" if SMP && X86_32 865 default "64" if SMP 866 ---help--- 867 This allows you to specify the maximum number of CPUs which this 868 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 869 supported value is 8192, otherwise the maximum value is 512. The 870 minimum value which makes sense is 2. 871 872 This is purely to save memory - each supported CPU adds 873 approximately eight kilobytes to the kernel image. 874 875config SCHED_SMT 876 bool "SMT (Hyperthreading) scheduler support" 877 depends on SMP 878 ---help--- 879 SMT scheduler support improves the CPU scheduler's decision making 880 when dealing with Intel Pentium 4 chips with HyperThreading at a 881 cost of slightly increased overhead in some places. If unsure say 882 N here. 883 884config SCHED_MC 885 def_bool y 886 prompt "Multi-core scheduler support" 887 depends on SMP 888 ---help--- 889 Multi-core scheduler support improves the CPU scheduler's decision 890 making when dealing with multi-core CPU chips at a cost of slightly 891 increased overhead in some places. If unsure say N here. 892 893source "kernel/Kconfig.preempt" 894 895config UP_LATE_INIT 896 def_bool y 897 depends on !SMP && X86_LOCAL_APIC 898 899config X86_UP_APIC 900 bool "Local APIC support on uniprocessors" if !PCI_MSI 901 default PCI_MSI 902 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 903 ---help--- 904 A local APIC (Advanced Programmable Interrupt Controller) is an 905 integrated interrupt controller in the CPU. If you have a single-CPU 906 system which has a processor with a local APIC, you can say Y here to 907 enable and use it. If you say Y here even though your machine doesn't 908 have a local APIC, then the kernel will still run with no slowdown at 909 all. The local APIC supports CPU-generated self-interrupts (timer, 910 performance counters), and the NMI watchdog which detects hard 911 lockups. 912 913config X86_UP_IOAPIC 914 bool "IO-APIC support on uniprocessors" 915 depends on X86_UP_APIC 916 ---help--- 917 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 918 SMP-capable replacement for PC-style interrupt controllers. Most 919 SMP systems and many recent uniprocessor systems have one. 920 921 If you have a single-CPU system with an IO-APIC, you can say Y here 922 to use it. If you say Y here even though your machine doesn't have 923 an IO-APIC, then the kernel will still run with no slowdown at all. 924 925config X86_LOCAL_APIC 926 def_bool y 927 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 928 select IRQ_DOMAIN_HIERARCHY 929 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 930 931config X86_IO_APIC 932 def_bool y 933 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 934 935config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 936 bool "Reroute for broken boot IRQs" 937 depends on X86_IO_APIC 938 ---help--- 939 This option enables a workaround that fixes a source of 940 spurious interrupts. This is recommended when threaded 941 interrupt handling is used on systems where the generation of 942 superfluous "boot interrupts" cannot be disabled. 943 944 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 945 entry in the chipset's IO-APIC is masked (as, e.g. the RT 946 kernel does during interrupt handling). On chipsets where this 947 boot IRQ generation cannot be disabled, this workaround keeps 948 the original IRQ line masked so that only the equivalent "boot 949 IRQ" is delivered to the CPUs. The workaround also tells the 950 kernel to set up the IRQ handler on the boot IRQ line. In this 951 way only one interrupt is delivered to the kernel. Otherwise 952 the spurious second interrupt may cause the kernel to bring 953 down (vital) interrupt lines. 954 955 Only affects "broken" chipsets. Interrupt sharing may be 956 increased on these systems. 957 958config X86_MCE 959 bool "Machine Check / overheating reporting" 960 select GENERIC_ALLOCATOR 961 default y 962 ---help--- 963 Machine Check support allows the processor to notify the 964 kernel if it detects a problem (e.g. overheating, data corruption). 965 The action the kernel takes depends on the severity of the problem, 966 ranging from warning messages to halting the machine. 967 968config X86_MCE_INTEL 969 def_bool y 970 prompt "Intel MCE features" 971 depends on X86_MCE && X86_LOCAL_APIC 972 ---help--- 973 Additional support for intel specific MCE features such as 974 the thermal monitor. 975 976config X86_MCE_AMD 977 def_bool y 978 prompt "AMD MCE features" 979 depends on X86_MCE && X86_LOCAL_APIC 980 ---help--- 981 Additional support for AMD specific MCE features such as 982 the DRAM Error Threshold. 983 984config X86_ANCIENT_MCE 985 bool "Support for old Pentium 5 / WinChip machine checks" 986 depends on X86_32 && X86_MCE 987 ---help--- 988 Include support for machine check handling on old Pentium 5 or WinChip 989 systems. These typically need to be enabled explicitly on the command 990 line. 991 992config X86_MCE_THRESHOLD 993 depends on X86_MCE_AMD || X86_MCE_INTEL 994 def_bool y 995 996config X86_MCE_INJECT 997 depends on X86_MCE 998 tristate "Machine check injector support" 999 ---help--- 1000 Provide support for injecting machine checks for testing purposes. 1001 If you don't know what a machine check is and you don't do kernel 1002 QA it is safe to say n. 1003 1004config X86_THERMAL_VECTOR 1005 def_bool y 1006 depends on X86_MCE_INTEL 1007 1008config X86_LEGACY_VM86 1009 bool "Legacy VM86 support" 1010 default n 1011 depends on X86_32 1012 ---help--- 1013 This option allows user programs to put the CPU into V8086 1014 mode, which is an 80286-era approximation of 16-bit real mode. 1015 1016 Some very old versions of X and/or vbetool require this option 1017 for user mode setting. Similarly, DOSEMU will use it if 1018 available to accelerate real mode DOS programs. However, any 1019 recent version of DOSEMU, X, or vbetool should be fully 1020 functional even without kernel VM86 support, as they will all 1021 fall back to software emulation. Nevertheless, if you are using 1022 a 16-bit DOS program where 16-bit performance matters, vm86 1023 mode might be faster than emulation and you might want to 1024 enable this option. 1025 1026 Note that any app that works on a 64-bit kernel is unlikely to 1027 need this option, as 64-bit kernels don't, and can't, support 1028 V8086 mode. This option is also unrelated to 16-bit protected 1029 mode and is not needed to run most 16-bit programs under Wine. 1030 1031 Enabling this option increases the complexity of the kernel 1032 and slows down exception handling a tiny bit. 1033 1034 If unsure, say N here. 1035 1036config VM86 1037 bool 1038 default X86_LEGACY_VM86 1039 1040config X86_16BIT 1041 bool "Enable support for 16-bit segments" if EXPERT 1042 default y 1043 depends on MODIFY_LDT_SYSCALL 1044 ---help--- 1045 This option is required by programs like Wine to run 16-bit 1046 protected mode legacy code on x86 processors. Disabling 1047 this option saves about 300 bytes on i386, or around 6K text 1048 plus 16K runtime memory on x86-64, 1049 1050config X86_ESPFIX32 1051 def_bool y 1052 depends on X86_16BIT && X86_32 1053 1054config X86_ESPFIX64 1055 def_bool y 1056 depends on X86_16BIT && X86_64 1057 1058config X86_VSYSCALL_EMULATION 1059 bool "Enable vsyscall emulation" if EXPERT 1060 default y 1061 depends on X86_64 1062 ---help--- 1063 This enables emulation of the legacy vsyscall page. Disabling 1064 it is roughly equivalent to booting with vsyscall=none, except 1065 that it will also disable the helpful warning if a program 1066 tries to use a vsyscall. With this option set to N, offending 1067 programs will just segfault, citing addresses of the form 1068 0xffffffffff600?00. 1069 1070 This option is required by many programs built before 2013, and 1071 care should be used even with newer programs if set to N. 1072 1073 Disabling this option saves about 7K of kernel size and 1074 possibly 4K of additional runtime pagetable memory. 1075 1076config TOSHIBA 1077 tristate "Toshiba Laptop support" 1078 depends on X86_32 1079 ---help--- 1080 This adds a driver to safely access the System Management Mode of 1081 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1082 not work on models with a Phoenix BIOS. The System Management Mode 1083 is used to set the BIOS and power saving options on Toshiba portables. 1084 1085 For information on utilities to make use of this driver see the 1086 Toshiba Linux utilities web site at: 1087 <http://www.buzzard.org.uk/toshiba/>. 1088 1089 Say Y if you intend to run this kernel on a Toshiba portable. 1090 Say N otherwise. 1091 1092config I8K 1093 tristate "Dell i8k legacy laptop support" 1094 select HWMON 1095 select SENSORS_DELL_SMM 1096 ---help--- 1097 This option enables legacy /proc/i8k userspace interface in hwmon 1098 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1099 temperature and allows controlling fan speeds of Dell laptops via 1100 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1101 it reports also power and hotkey status. For fan speed control is 1102 needed userspace package i8kutils. 1103 1104 Say Y if you intend to run this kernel on old Dell laptops or want to 1105 use userspace package i8kutils. 1106 Say N otherwise. 1107 1108config X86_REBOOTFIXUPS 1109 bool "Enable X86 board specific fixups for reboot" 1110 depends on X86_32 1111 ---help--- 1112 This enables chipset and/or board specific fixups to be done 1113 in order to get reboot to work correctly. This is only needed on 1114 some combinations of hardware and BIOS. The symptom, for which 1115 this config is intended, is when reboot ends with a stalled/hung 1116 system. 1117 1118 Currently, the only fixup is for the Geode machines using 1119 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1120 1121 Say Y if you want to enable the fixup. Currently, it's safe to 1122 enable this option even if you don't need it. 1123 Say N otherwise. 1124 1125config MICROCODE 1126 tristate "CPU microcode loading support" 1127 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1128 select FW_LOADER 1129 ---help--- 1130 1131 If you say Y here, you will be able to update the microcode on 1132 certain Intel and AMD processors. The Intel support is for the 1133 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1134 Xeon etc. The AMD support is for families 0x10 and later. You will 1135 obviously need the actual microcode binary data itself which is not 1136 shipped with the Linux kernel. 1137 1138 This option selects the general module only, you need to select 1139 at least one vendor specific module as well. 1140 1141 To compile this driver as a module, choose M here: the module 1142 will be called microcode. 1143 1144config MICROCODE_INTEL 1145 bool "Intel microcode loading support" 1146 depends on MICROCODE 1147 default MICROCODE 1148 select FW_LOADER 1149 ---help--- 1150 This options enables microcode patch loading support for Intel 1151 processors. 1152 1153 For the current Intel microcode data package go to 1154 <https://downloadcenter.intel.com> and search for 1155 'Linux Processor Microcode Data File'. 1156 1157config MICROCODE_AMD 1158 bool "AMD microcode loading support" 1159 depends on MICROCODE 1160 select FW_LOADER 1161 ---help--- 1162 If you select this option, microcode patch loading support for AMD 1163 processors will be enabled. 1164 1165config MICROCODE_OLD_INTERFACE 1166 def_bool y 1167 depends on MICROCODE 1168 1169config MICROCODE_INTEL_EARLY 1170 bool 1171 1172config MICROCODE_AMD_EARLY 1173 bool 1174 1175config MICROCODE_EARLY 1176 bool "Early load microcode" 1177 depends on MICROCODE=y && BLK_DEV_INITRD 1178 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1179 select MICROCODE_AMD_EARLY if MICROCODE_AMD 1180 default y 1181 help 1182 This option provides functionality to read additional microcode data 1183 at the beginning of initrd image. The data tells kernel to load 1184 microcode to CPU's as early as possible. No functional change if no 1185 microcode data is glued to the initrd, therefore it's safe to say Y. 1186 1187config X86_MSR 1188 tristate "/dev/cpu/*/msr - Model-specific register support" 1189 ---help--- 1190 This device gives privileged processes access to the x86 1191 Model-Specific Registers (MSRs). It is a character device with 1192 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1193 MSR accesses are directed to a specific CPU on multi-processor 1194 systems. 1195 1196config X86_CPUID 1197 tristate "/dev/cpu/*/cpuid - CPU information support" 1198 ---help--- 1199 This device gives processes access to the x86 CPUID instruction to 1200 be executed on a specific processor. It is a character device 1201 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1202 /dev/cpu/31/cpuid. 1203 1204choice 1205 prompt "High Memory Support" 1206 default HIGHMEM4G 1207 depends on X86_32 1208 1209config NOHIGHMEM 1210 bool "off" 1211 ---help--- 1212 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1213 However, the address space of 32-bit x86 processors is only 4 1214 Gigabytes large. That means that, if you have a large amount of 1215 physical memory, not all of it can be "permanently mapped" by the 1216 kernel. The physical memory that's not permanently mapped is called 1217 "high memory". 1218 1219 If you are compiling a kernel which will never run on a machine with 1220 more than 1 Gigabyte total physical RAM, answer "off" here (default 1221 choice and suitable for most users). This will result in a "3GB/1GB" 1222 split: 3GB are mapped so that each process sees a 3GB virtual memory 1223 space and the remaining part of the 4GB virtual memory space is used 1224 by the kernel to permanently map as much physical memory as 1225 possible. 1226 1227 If the machine has between 1 and 4 Gigabytes physical RAM, then 1228 answer "4GB" here. 1229 1230 If more than 4 Gigabytes is used then answer "64GB" here. This 1231 selection turns Intel PAE (Physical Address Extension) mode on. 1232 PAE implements 3-level paging on IA32 processors. PAE is fully 1233 supported by Linux, PAE mode is implemented on all recent Intel 1234 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1235 then the kernel will not boot on CPUs that don't support PAE! 1236 1237 The actual amount of total physical memory will either be 1238 auto detected or can be forced by using a kernel command line option 1239 such as "mem=256M". (Try "man bootparam" or see the documentation of 1240 your boot loader (lilo or loadlin) about how to pass options to the 1241 kernel at boot time.) 1242 1243 If unsure, say "off". 1244 1245config HIGHMEM4G 1246 bool "4GB" 1247 ---help--- 1248 Select this if you have a 32-bit processor and between 1 and 4 1249 gigabytes of physical RAM. 1250 1251config HIGHMEM64G 1252 bool "64GB" 1253 depends on !M486 1254 select X86_PAE 1255 ---help--- 1256 Select this if you have a 32-bit processor and more than 4 1257 gigabytes of physical RAM. 1258 1259endchoice 1260 1261choice 1262 prompt "Memory split" if EXPERT 1263 default VMSPLIT_3G 1264 depends on X86_32 1265 ---help--- 1266 Select the desired split between kernel and user memory. 1267 1268 If the address range available to the kernel is less than the 1269 physical memory installed, the remaining memory will be available 1270 as "high memory". Accessing high memory is a little more costly 1271 than low memory, as it needs to be mapped into the kernel first. 1272 Note that increasing the kernel address space limits the range 1273 available to user programs, making the address space there 1274 tighter. Selecting anything other than the default 3G/1G split 1275 will also likely make your kernel incompatible with binary-only 1276 kernel modules. 1277 1278 If you are not absolutely sure what you are doing, leave this 1279 option alone! 1280 1281 config VMSPLIT_3G 1282 bool "3G/1G user/kernel split" 1283 config VMSPLIT_3G_OPT 1284 depends on !X86_PAE 1285 bool "3G/1G user/kernel split (for full 1G low memory)" 1286 config VMSPLIT_2G 1287 bool "2G/2G user/kernel split" 1288 config VMSPLIT_2G_OPT 1289 depends on !X86_PAE 1290 bool "2G/2G user/kernel split (for full 2G low memory)" 1291 config VMSPLIT_1G 1292 bool "1G/3G user/kernel split" 1293endchoice 1294 1295config PAGE_OFFSET 1296 hex 1297 default 0xB0000000 if VMSPLIT_3G_OPT 1298 default 0x80000000 if VMSPLIT_2G 1299 default 0x78000000 if VMSPLIT_2G_OPT 1300 default 0x40000000 if VMSPLIT_1G 1301 default 0xC0000000 1302 depends on X86_32 1303 1304config HIGHMEM 1305 def_bool y 1306 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1307 1308config X86_PAE 1309 bool "PAE (Physical Address Extension) Support" 1310 depends on X86_32 && !HIGHMEM4G 1311 select SWIOTLB 1312 ---help--- 1313 PAE is required for NX support, and furthermore enables 1314 larger swapspace support for non-overcommit purposes. It 1315 has the cost of more pagetable lookup overhead, and also 1316 consumes more pagetable space per process. 1317 1318config ARCH_PHYS_ADDR_T_64BIT 1319 def_bool y 1320 depends on X86_64 || X86_PAE 1321 1322config ARCH_DMA_ADDR_T_64BIT 1323 def_bool y 1324 depends on X86_64 || HIGHMEM64G 1325 1326config X86_DIRECT_GBPAGES 1327 def_bool y 1328 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1329 ---help--- 1330 Certain kernel features effectively disable kernel 1331 linear 1 GB mappings (even if the CPU otherwise 1332 supports them), so don't confuse the user by printing 1333 that we have them enabled. 1334 1335# Common NUMA Features 1336config NUMA 1337 bool "Numa Memory Allocation and Scheduler Support" 1338 depends on SMP 1339 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1340 default y if X86_BIGSMP 1341 ---help--- 1342 Enable NUMA (Non Uniform Memory Access) support. 1343 1344 The kernel will try to allocate memory used by a CPU on the 1345 local memory controller of the CPU and add some more 1346 NUMA awareness to the kernel. 1347 1348 For 64-bit this is recommended if the system is Intel Core i7 1349 (or later), AMD Opteron, or EM64T NUMA. 1350 1351 For 32-bit this is only needed if you boot a 32-bit 1352 kernel on a 64-bit NUMA platform. 1353 1354 Otherwise, you should say N. 1355 1356config AMD_NUMA 1357 def_bool y 1358 prompt "Old style AMD Opteron NUMA detection" 1359 depends on X86_64 && NUMA && PCI 1360 ---help--- 1361 Enable AMD NUMA node topology detection. You should say Y here if 1362 you have a multi processor AMD system. This uses an old method to 1363 read the NUMA configuration directly from the builtin Northbridge 1364 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1365 which also takes priority if both are compiled in. 1366 1367config X86_64_ACPI_NUMA 1368 def_bool y 1369 prompt "ACPI NUMA detection" 1370 depends on X86_64 && NUMA && ACPI && PCI 1371 select ACPI_NUMA 1372 ---help--- 1373 Enable ACPI SRAT based node topology detection. 1374 1375# Some NUMA nodes have memory ranges that span 1376# other nodes. Even though a pfn is valid and 1377# between a node's start and end pfns, it may not 1378# reside on that node. See memmap_init_zone() 1379# for details. 1380config NODES_SPAN_OTHER_NODES 1381 def_bool y 1382 depends on X86_64_ACPI_NUMA 1383 1384config NUMA_EMU 1385 bool "NUMA emulation" 1386 depends on NUMA 1387 ---help--- 1388 Enable NUMA emulation. A flat machine will be split 1389 into virtual nodes when booted with "numa=fake=N", where N is the 1390 number of nodes. This is only useful for debugging. 1391 1392config NODES_SHIFT 1393 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1394 range 1 10 1395 default "10" if MAXSMP 1396 default "6" if X86_64 1397 default "3" 1398 depends on NEED_MULTIPLE_NODES 1399 ---help--- 1400 Specify the maximum number of NUMA Nodes available on the target 1401 system. Increases memory reserved to accommodate various tables. 1402 1403config ARCH_HAVE_MEMORY_PRESENT 1404 def_bool y 1405 depends on X86_32 && DISCONTIGMEM 1406 1407config NEED_NODE_MEMMAP_SIZE 1408 def_bool y 1409 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1410 1411config ARCH_FLATMEM_ENABLE 1412 def_bool y 1413 depends on X86_32 && !NUMA 1414 1415config ARCH_DISCONTIGMEM_ENABLE 1416 def_bool y 1417 depends on NUMA && X86_32 1418 1419config ARCH_DISCONTIGMEM_DEFAULT 1420 def_bool y 1421 depends on NUMA && X86_32 1422 1423config ARCH_SPARSEMEM_ENABLE 1424 def_bool y 1425 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1426 select SPARSEMEM_STATIC if X86_32 1427 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1428 1429config ARCH_SPARSEMEM_DEFAULT 1430 def_bool y 1431 depends on X86_64 1432 1433config ARCH_SELECT_MEMORY_MODEL 1434 def_bool y 1435 depends on ARCH_SPARSEMEM_ENABLE 1436 1437config ARCH_MEMORY_PROBE 1438 bool "Enable sysfs memory/probe interface" 1439 depends on X86_64 && MEMORY_HOTPLUG 1440 help 1441 This option enables a sysfs memory/probe interface for testing. 1442 See Documentation/memory-hotplug.txt for more information. 1443 If you are unsure how to answer this question, answer N. 1444 1445config ARCH_PROC_KCORE_TEXT 1446 def_bool y 1447 depends on X86_64 && PROC_KCORE 1448 1449config ILLEGAL_POINTER_VALUE 1450 hex 1451 default 0 if X86_32 1452 default 0xdead000000000000 if X86_64 1453 1454source "mm/Kconfig" 1455 1456config X86_PMEM_LEGACY_DEVICE 1457 bool 1458 1459config X86_PMEM_LEGACY 1460 tristate "Support non-standard NVDIMMs and ADR protected memory" 1461 depends on PHYS_ADDR_T_64BIT 1462 depends on BLK_DEV 1463 select X86_PMEM_LEGACY_DEVICE 1464 select LIBNVDIMM 1465 help 1466 Treat memory marked using the non-standard e820 type of 12 as used 1467 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1468 The kernel will offer these regions to the 'pmem' driver so 1469 they can be used for persistent storage. 1470 1471 Say Y if unsure. 1472 1473config HIGHPTE 1474 bool "Allocate 3rd-level pagetables from highmem" 1475 depends on HIGHMEM 1476 ---help--- 1477 The VM uses one page table entry for each page of physical memory. 1478 For systems with a lot of RAM, this can be wasteful of precious 1479 low memory. Setting this option will put user-space page table 1480 entries in high memory. 1481 1482config X86_CHECK_BIOS_CORRUPTION 1483 bool "Check for low memory corruption" 1484 ---help--- 1485 Periodically check for memory corruption in low memory, which 1486 is suspected to be caused by BIOS. Even when enabled in the 1487 configuration, it is disabled at runtime. Enable it by 1488 setting "memory_corruption_check=1" on the kernel command 1489 line. By default it scans the low 64k of memory every 60 1490 seconds; see the memory_corruption_check_size and 1491 memory_corruption_check_period parameters in 1492 Documentation/kernel-parameters.txt to adjust this. 1493 1494 When enabled with the default parameters, this option has 1495 almost no overhead, as it reserves a relatively small amount 1496 of memory and scans it infrequently. It both detects corruption 1497 and prevents it from affecting the running system. 1498 1499 It is, however, intended as a diagnostic tool; if repeatable 1500 BIOS-originated corruption always affects the same memory, 1501 you can use memmap= to prevent the kernel from using that 1502 memory. 1503 1504config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1505 bool "Set the default setting of memory_corruption_check" 1506 depends on X86_CHECK_BIOS_CORRUPTION 1507 default y 1508 ---help--- 1509 Set whether the default state of memory_corruption_check is 1510 on or off. 1511 1512config X86_RESERVE_LOW 1513 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1514 default 64 1515 range 4 640 1516 ---help--- 1517 Specify the amount of low memory to reserve for the BIOS. 1518 1519 The first page contains BIOS data structures that the kernel 1520 must not use, so that page must always be reserved. 1521 1522 By default we reserve the first 64K of physical RAM, as a 1523 number of BIOSes are known to corrupt that memory range 1524 during events such as suspend/resume or monitor cable 1525 insertion, so it must not be used by the kernel. 1526 1527 You can set this to 4 if you are absolutely sure that you 1528 trust the BIOS to get all its memory reservations and usages 1529 right. If you know your BIOS have problems beyond the 1530 default 64K area, you can set this to 640 to avoid using the 1531 entire low memory range. 1532 1533 If you have doubts about the BIOS (e.g. suspend/resume does 1534 not work or there's kernel crashes after certain hardware 1535 hotplug events) then you might want to enable 1536 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1537 typical corruption patterns. 1538 1539 Leave this to the default value of 64 if you are unsure. 1540 1541config MATH_EMULATION 1542 bool 1543 depends on MODIFY_LDT_SYSCALL 1544 prompt "Math emulation" if X86_32 1545 ---help--- 1546 Linux can emulate a math coprocessor (used for floating point 1547 operations) if you don't have one. 486DX and Pentium processors have 1548 a math coprocessor built in, 486SX and 386 do not, unless you added 1549 a 487DX or 387, respectively. (The messages during boot time can 1550 give you some hints here ["man dmesg"].) Everyone needs either a 1551 coprocessor or this emulation. 1552 1553 If you don't have a math coprocessor, you need to say Y here; if you 1554 say Y here even though you have a coprocessor, the coprocessor will 1555 be used nevertheless. (This behavior can be changed with the kernel 1556 command line option "no387", which comes handy if your coprocessor 1557 is broken. Try "man bootparam" or see the documentation of your boot 1558 loader (lilo or loadlin) about how to pass options to the kernel at 1559 boot time.) This means that it is a good idea to say Y here if you 1560 intend to use this kernel on different machines. 1561 1562 More information about the internals of the Linux math coprocessor 1563 emulation can be found in <file:arch/x86/math-emu/README>. 1564 1565 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1566 kernel, it won't hurt. 1567 1568config MTRR 1569 def_bool y 1570 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1571 ---help--- 1572 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1573 the Memory Type Range Registers (MTRRs) may be used to control 1574 processor access to memory ranges. This is most useful if you have 1575 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1576 allows bus write transfers to be combined into a larger transfer 1577 before bursting over the PCI/AGP bus. This can increase performance 1578 of image write operations 2.5 times or more. Saying Y here creates a 1579 /proc/mtrr file which may be used to manipulate your processor's 1580 MTRRs. Typically the X server should use this. 1581 1582 This code has a reasonably generic interface so that similar 1583 control registers on other processors can be easily supported 1584 as well: 1585 1586 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1587 Registers (ARRs) which provide a similar functionality to MTRRs. For 1588 these, the ARRs are used to emulate the MTRRs. 1589 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1590 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1591 write-combining. All of these processors are supported by this code 1592 and it makes sense to say Y here if you have one of them. 1593 1594 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1595 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1596 can lead to all sorts of problems, so it's good to say Y here. 1597 1598 You can safely say Y even if your machine doesn't have MTRRs, you'll 1599 just add about 9 KB to your kernel. 1600 1601 See <file:Documentation/x86/mtrr.txt> for more information. 1602 1603config MTRR_SANITIZER 1604 def_bool y 1605 prompt "MTRR cleanup support" 1606 depends on MTRR 1607 ---help--- 1608 Convert MTRR layout from continuous to discrete, so X drivers can 1609 add writeback entries. 1610 1611 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1612 The largest mtrr entry size for a continuous block can be set with 1613 mtrr_chunk_size. 1614 1615 If unsure, say Y. 1616 1617config MTRR_SANITIZER_ENABLE_DEFAULT 1618 int "MTRR cleanup enable value (0-1)" 1619 range 0 1 1620 default "0" 1621 depends on MTRR_SANITIZER 1622 ---help--- 1623 Enable mtrr cleanup default value 1624 1625config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1626 int "MTRR cleanup spare reg num (0-7)" 1627 range 0 7 1628 default "1" 1629 depends on MTRR_SANITIZER 1630 ---help--- 1631 mtrr cleanup spare entries default, it can be changed via 1632 mtrr_spare_reg_nr=N on the kernel command line. 1633 1634config X86_PAT 1635 def_bool y 1636 prompt "x86 PAT support" if EXPERT 1637 depends on MTRR 1638 ---help--- 1639 Use PAT attributes to setup page level cache control. 1640 1641 PATs are the modern equivalents of MTRRs and are much more 1642 flexible than MTRRs. 1643 1644 Say N here if you see bootup problems (boot crash, boot hang, 1645 spontaneous reboots) or a non-working video driver. 1646 1647 If unsure, say Y. 1648 1649config ARCH_USES_PG_UNCACHED 1650 def_bool y 1651 depends on X86_PAT 1652 1653config ARCH_RANDOM 1654 def_bool y 1655 prompt "x86 architectural random number generator" if EXPERT 1656 ---help--- 1657 Enable the x86 architectural RDRAND instruction 1658 (Intel Bull Mountain technology) to generate random numbers. 1659 If supported, this is a high bandwidth, cryptographically 1660 secure hardware random number generator. 1661 1662config X86_SMAP 1663 def_bool y 1664 prompt "Supervisor Mode Access Prevention" if EXPERT 1665 ---help--- 1666 Supervisor Mode Access Prevention (SMAP) is a security 1667 feature in newer Intel processors. There is a small 1668 performance cost if this enabled and turned on; there is 1669 also a small increase in the kernel size if this is enabled. 1670 1671 If unsure, say Y. 1672 1673config X86_INTEL_MPX 1674 prompt "Intel MPX (Memory Protection Extensions)" 1675 def_bool n 1676 depends on CPU_SUP_INTEL 1677 ---help--- 1678 MPX provides hardware features that can be used in 1679 conjunction with compiler-instrumented code to check 1680 memory references. It is designed to detect buffer 1681 overflow or underflow bugs. 1682 1683 This option enables running applications which are 1684 instrumented or otherwise use MPX. It does not use MPX 1685 itself inside the kernel or to protect the kernel 1686 against bad memory references. 1687 1688 Enabling this option will make the kernel larger: 1689 ~8k of kernel text and 36 bytes of data on a 64-bit 1690 defconfig. It adds a long to the 'mm_struct' which 1691 will increase the kernel memory overhead of each 1692 process and adds some branches to paths used during 1693 exec() and munmap(). 1694 1695 For details, see Documentation/x86/intel_mpx.txt 1696 1697 If unsure, say N. 1698 1699config EFI 1700 bool "EFI runtime service support" 1701 depends on ACPI 1702 select UCS2_STRING 1703 select EFI_RUNTIME_WRAPPERS 1704 ---help--- 1705 This enables the kernel to use EFI runtime services that are 1706 available (such as the EFI variable services). 1707 1708 This option is only useful on systems that have EFI firmware. 1709 In addition, you should use the latest ELILO loader available 1710 at <http://elilo.sourceforge.net> in order to take advantage 1711 of EFI runtime services. However, even with this option, the 1712 resultant kernel should continue to boot on existing non-EFI 1713 platforms. 1714 1715config EFI_STUB 1716 bool "EFI stub support" 1717 depends on EFI && !X86_USE_3DNOW 1718 select RELOCATABLE 1719 ---help--- 1720 This kernel feature allows a bzImage to be loaded directly 1721 by EFI firmware without the use of a bootloader. 1722 1723 See Documentation/efi-stub.txt for more information. 1724 1725config EFI_MIXED 1726 bool "EFI mixed-mode support" 1727 depends on EFI_STUB && X86_64 1728 ---help--- 1729 Enabling this feature allows a 64-bit kernel to be booted 1730 on a 32-bit firmware, provided that your CPU supports 64-bit 1731 mode. 1732 1733 Note that it is not possible to boot a mixed-mode enabled 1734 kernel via the EFI boot stub - a bootloader that supports 1735 the EFI handover protocol must be used. 1736 1737 If unsure, say N. 1738 1739config SECCOMP 1740 def_bool y 1741 prompt "Enable seccomp to safely compute untrusted bytecode" 1742 ---help--- 1743 This kernel feature is useful for number crunching applications 1744 that may need to compute untrusted bytecode during their 1745 execution. By using pipes or other transports made available to 1746 the process as file descriptors supporting the read/write 1747 syscalls, it's possible to isolate those applications in 1748 their own address space using seccomp. Once seccomp is 1749 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1750 and the task is only allowed to execute a few safe syscalls 1751 defined by each seccomp mode. 1752 1753 If unsure, say Y. Only embedded should say N here. 1754 1755source kernel/Kconfig.hz 1756 1757config KEXEC 1758 bool "kexec system call" 1759 select KEXEC_CORE 1760 ---help--- 1761 kexec is a system call that implements the ability to shutdown your 1762 current kernel, and to start another kernel. It is like a reboot 1763 but it is independent of the system firmware. And like a reboot 1764 you can start any kernel with it, not just Linux. 1765 1766 The name comes from the similarity to the exec system call. 1767 1768 It is an ongoing process to be certain the hardware in a machine 1769 is properly shutdown, so do not be surprised if this code does not 1770 initially work for you. As of this writing the exact hardware 1771 interface is strongly in flux, so no good recommendation can be 1772 made. 1773 1774config KEXEC_FILE 1775 bool "kexec file based system call" 1776 select KEXEC_CORE 1777 select BUILD_BIN2C 1778 depends on X86_64 1779 depends on CRYPTO=y 1780 depends on CRYPTO_SHA256=y 1781 ---help--- 1782 This is new version of kexec system call. This system call is 1783 file based and takes file descriptors as system call argument 1784 for kernel and initramfs as opposed to list of segments as 1785 accepted by previous system call. 1786 1787config KEXEC_VERIFY_SIG 1788 bool "Verify kernel signature during kexec_file_load() syscall" 1789 depends on KEXEC_FILE 1790 ---help--- 1791 This option makes kernel signature verification mandatory for 1792 the kexec_file_load() syscall. 1793 1794 In addition to that option, you need to enable signature 1795 verification for the corresponding kernel image type being 1796 loaded in order for this to work. 1797 1798config KEXEC_BZIMAGE_VERIFY_SIG 1799 bool "Enable bzImage signature verification support" 1800 depends on KEXEC_VERIFY_SIG 1801 depends on SIGNED_PE_FILE_VERIFICATION 1802 select SYSTEM_TRUSTED_KEYRING 1803 ---help--- 1804 Enable bzImage signature verification support. 1805 1806config CRASH_DUMP 1807 bool "kernel crash dumps" 1808 depends on X86_64 || (X86_32 && HIGHMEM) 1809 ---help--- 1810 Generate crash dump after being started by kexec. 1811 This should be normally only set in special crash dump kernels 1812 which are loaded in the main kernel with kexec-tools into 1813 a specially reserved region and then later executed after 1814 a crash by kdump/kexec. The crash dump kernel must be compiled 1815 to a memory address not used by the main kernel or BIOS using 1816 PHYSICAL_START, or it must be built as a relocatable image 1817 (CONFIG_RELOCATABLE=y). 1818 For more details see Documentation/kdump/kdump.txt 1819 1820config KEXEC_JUMP 1821 bool "kexec jump" 1822 depends on KEXEC && HIBERNATION 1823 ---help--- 1824 Jump between original kernel and kexeced kernel and invoke 1825 code in physical address mode via KEXEC 1826 1827config PHYSICAL_START 1828 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1829 default "0x1000000" 1830 ---help--- 1831 This gives the physical address where the kernel is loaded. 1832 1833 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1834 bzImage will decompress itself to above physical address and 1835 run from there. Otherwise, bzImage will run from the address where 1836 it has been loaded by the boot loader and will ignore above physical 1837 address. 1838 1839 In normal kdump cases one does not have to set/change this option 1840 as now bzImage can be compiled as a completely relocatable image 1841 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1842 address. This option is mainly useful for the folks who don't want 1843 to use a bzImage for capturing the crash dump and want to use a 1844 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1845 to be specifically compiled to run from a specific memory area 1846 (normally a reserved region) and this option comes handy. 1847 1848 So if you are using bzImage for capturing the crash dump, 1849 leave the value here unchanged to 0x1000000 and set 1850 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1851 for capturing the crash dump change this value to start of 1852 the reserved region. In other words, it can be set based on 1853 the "X" value as specified in the "crashkernel=YM@XM" 1854 command line boot parameter passed to the panic-ed 1855 kernel. Please take a look at Documentation/kdump/kdump.txt 1856 for more details about crash dumps. 1857 1858 Usage of bzImage for capturing the crash dump is recommended as 1859 one does not have to build two kernels. Same kernel can be used 1860 as production kernel and capture kernel. Above option should have 1861 gone away after relocatable bzImage support is introduced. But it 1862 is present because there are users out there who continue to use 1863 vmlinux for dump capture. This option should go away down the 1864 line. 1865 1866 Don't change this unless you know what you are doing. 1867 1868config RELOCATABLE 1869 bool "Build a relocatable kernel" 1870 default y 1871 ---help--- 1872 This builds a kernel image that retains relocation information 1873 so it can be loaded someplace besides the default 1MB. 1874 The relocations tend to make the kernel binary about 10% larger, 1875 but are discarded at runtime. 1876 1877 One use is for the kexec on panic case where the recovery kernel 1878 must live at a different physical address than the primary 1879 kernel. 1880 1881 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1882 it has been loaded at and the compile time physical address 1883 (CONFIG_PHYSICAL_START) is used as the minimum location. 1884 1885config RANDOMIZE_BASE 1886 bool "Randomize the address of the kernel image" 1887 depends on RELOCATABLE 1888 default n 1889 ---help--- 1890 Randomizes the physical and virtual address at which the 1891 kernel image is decompressed, as a security feature that 1892 deters exploit attempts relying on knowledge of the location 1893 of kernel internals. 1894 1895 Entropy is generated using the RDRAND instruction if it is 1896 supported. If RDTSC is supported, it is used as well. If 1897 neither RDRAND nor RDTSC are supported, then randomness is 1898 read from the i8254 timer. 1899 1900 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1901 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1902 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1903 minimum of 2MiB, only 10 bits of entropy is theoretically 1904 possible. At best, due to page table layouts, 64-bit can use 1905 9 bits of entropy and 32-bit uses 8 bits. 1906 1907 If unsure, say N. 1908 1909config RANDOMIZE_BASE_MAX_OFFSET 1910 hex "Maximum kASLR offset allowed" if EXPERT 1911 depends on RANDOMIZE_BASE 1912 range 0x0 0x20000000 if X86_32 1913 default "0x20000000" if X86_32 1914 range 0x0 0x40000000 if X86_64 1915 default "0x40000000" if X86_64 1916 ---help--- 1917 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1918 memory is used to determine the maximal offset in bytes that will 1919 be applied to the kernel when kernel Address Space Layout 1920 Randomization (kASLR) is active. This must be a multiple of 1921 PHYSICAL_ALIGN. 1922 1923 On 32-bit this is limited to 512MiB by page table layouts. The 1924 default is 512MiB. 1925 1926 On 64-bit this is limited by how the kernel fixmap page table is 1927 positioned, so this cannot be larger than 1GiB currently. Without 1928 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1929 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1930 modules area will shrink to compensate, up to the current maximum 1931 1GiB to 1GiB split. The default is 1GiB. 1932 1933 If unsure, leave at the default value. 1934 1935# Relocation on x86 needs some additional build support 1936config X86_NEED_RELOCS 1937 def_bool y 1938 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1939 1940config PHYSICAL_ALIGN 1941 hex "Alignment value to which kernel should be aligned" 1942 default "0x200000" 1943 range 0x2000 0x1000000 if X86_32 1944 range 0x200000 0x1000000 if X86_64 1945 ---help--- 1946 This value puts the alignment restrictions on physical address 1947 where kernel is loaded and run from. Kernel is compiled for an 1948 address which meets above alignment restriction. 1949 1950 If bootloader loads the kernel at a non-aligned address and 1951 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1952 address aligned to above value and run from there. 1953 1954 If bootloader loads the kernel at a non-aligned address and 1955 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1956 load address and decompress itself to the address it has been 1957 compiled for and run from there. The address for which kernel is 1958 compiled already meets above alignment restrictions. Hence the 1959 end result is that kernel runs from a physical address meeting 1960 above alignment restrictions. 1961 1962 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1963 this value must be a multiple of 0x200000. 1964 1965 Don't change this unless you know what you are doing. 1966 1967config HOTPLUG_CPU 1968 bool "Support for hot-pluggable CPUs" 1969 depends on SMP 1970 ---help--- 1971 Say Y here to allow turning CPUs off and on. CPUs can be 1972 controlled through /sys/devices/system/cpu. 1973 ( Note: power management support will enable this option 1974 automatically on SMP systems. ) 1975 Say N if you want to disable CPU hotplug. 1976 1977config BOOTPARAM_HOTPLUG_CPU0 1978 bool "Set default setting of cpu0_hotpluggable" 1979 default n 1980 depends on HOTPLUG_CPU 1981 ---help--- 1982 Set whether default state of cpu0_hotpluggable is on or off. 1983 1984 Say Y here to enable CPU0 hotplug by default. If this switch 1985 is turned on, there is no need to give cpu0_hotplug kernel 1986 parameter and the CPU0 hotplug feature is enabled by default. 1987 1988 Please note: there are two known CPU0 dependencies if you want 1989 to enable the CPU0 hotplug feature either by this switch or by 1990 cpu0_hotplug kernel parameter. 1991 1992 First, resume from hibernate or suspend always starts from CPU0. 1993 So hibernate and suspend are prevented if CPU0 is offline. 1994 1995 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1996 offline if any interrupt can not migrate out of CPU0. There may 1997 be other CPU0 dependencies. 1998 1999 Please make sure the dependencies are under your control before 2000 you enable this feature. 2001 2002 Say N if you don't want to enable CPU0 hotplug feature by default. 2003 You still can enable the CPU0 hotplug feature at boot by kernel 2004 parameter cpu0_hotplug. 2005 2006config DEBUG_HOTPLUG_CPU0 2007 def_bool n 2008 prompt "Debug CPU0 hotplug" 2009 depends on HOTPLUG_CPU 2010 ---help--- 2011 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2012 soon as possible and boots up userspace with CPU0 offlined. User 2013 can online CPU0 back after boot time. 2014 2015 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2016 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2017 compilation or giving cpu0_hotplug kernel parameter at boot. 2018 2019 If unsure, say N. 2020 2021config COMPAT_VDSO 2022 def_bool n 2023 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2024 depends on X86_32 || IA32_EMULATION 2025 ---help--- 2026 Certain buggy versions of glibc will crash if they are 2027 presented with a 32-bit vDSO that is not mapped at the address 2028 indicated in its segment table. 2029 2030 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2031 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2032 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2033 the only released version with the bug, but OpenSUSE 9 2034 contains a buggy "glibc 2.3.2". 2035 2036 The symptom of the bug is that everything crashes on startup, saying: 2037 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2038 2039 Saying Y here changes the default value of the vdso32 boot 2040 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2041 This works around the glibc bug but hurts performance. 2042 2043 If unsure, say N: if you are compiling your own kernel, you 2044 are unlikely to be using a buggy version of glibc. 2045 2046config CMDLINE_BOOL 2047 bool "Built-in kernel command line" 2048 ---help--- 2049 Allow for specifying boot arguments to the kernel at 2050 build time. On some systems (e.g. embedded ones), it is 2051 necessary or convenient to provide some or all of the 2052 kernel boot arguments with the kernel itself (that is, 2053 to not rely on the boot loader to provide them.) 2054 2055 To compile command line arguments into the kernel, 2056 set this option to 'Y', then fill in the 2057 boot arguments in CONFIG_CMDLINE. 2058 2059 Systems with fully functional boot loaders (i.e. non-embedded) 2060 should leave this option set to 'N'. 2061 2062config CMDLINE 2063 string "Built-in kernel command string" 2064 depends on CMDLINE_BOOL 2065 default "" 2066 ---help--- 2067 Enter arguments here that should be compiled into the kernel 2068 image and used at boot time. If the boot loader provides a 2069 command line at boot time, it is appended to this string to 2070 form the full kernel command line, when the system boots. 2071 2072 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2073 change this behavior. 2074 2075 In most cases, the command line (whether built-in or provided 2076 by the boot loader) should specify the device for the root 2077 file system. 2078 2079config CMDLINE_OVERRIDE 2080 bool "Built-in command line overrides boot loader arguments" 2081 depends on CMDLINE_BOOL 2082 ---help--- 2083 Set this option to 'Y' to have the kernel ignore the boot loader 2084 command line, and use ONLY the built-in command line. 2085 2086 This is used to work around broken boot loaders. This should 2087 be set to 'N' under normal conditions. 2088 2089config MODIFY_LDT_SYSCALL 2090 bool "Enable the LDT (local descriptor table)" if EXPERT 2091 default y 2092 ---help--- 2093 Linux can allow user programs to install a per-process x86 2094 Local Descriptor Table (LDT) using the modify_ldt(2) system 2095 call. This is required to run 16-bit or segmented code such as 2096 DOSEMU or some Wine programs. It is also used by some very old 2097 threading libraries. 2098 2099 Enabling this feature adds a small amount of overhead to 2100 context switches and increases the low-level kernel attack 2101 surface. Disabling it removes the modify_ldt(2) system call. 2102 2103 Saying 'N' here may make sense for embedded or server kernels. 2104 2105source "kernel/livepatch/Kconfig" 2106 2107endmenu 2108 2109config ARCH_ENABLE_MEMORY_HOTPLUG 2110 def_bool y 2111 depends on X86_64 || (X86_32 && HIGHMEM) 2112 2113config ARCH_ENABLE_MEMORY_HOTREMOVE 2114 def_bool y 2115 depends on MEMORY_HOTPLUG 2116 2117config USE_PERCPU_NUMA_NODE_ID 2118 def_bool y 2119 depends on NUMA 2120 2121config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2122 def_bool y 2123 depends on X86_64 || X86_PAE 2124 2125config ARCH_ENABLE_HUGEPAGE_MIGRATION 2126 def_bool y 2127 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2128 2129menu "Power management and ACPI options" 2130 2131config ARCH_HIBERNATION_HEADER 2132 def_bool y 2133 depends on X86_64 && HIBERNATION 2134 2135source "kernel/power/Kconfig" 2136 2137source "drivers/acpi/Kconfig" 2138 2139source "drivers/sfi/Kconfig" 2140 2141config X86_APM_BOOT 2142 def_bool y 2143 depends on APM 2144 2145menuconfig APM 2146 tristate "APM (Advanced Power Management) BIOS support" 2147 depends on X86_32 && PM_SLEEP 2148 ---help--- 2149 APM is a BIOS specification for saving power using several different 2150 techniques. This is mostly useful for battery powered laptops with 2151 APM compliant BIOSes. If you say Y here, the system time will be 2152 reset after a RESUME operation, the /proc/apm device will provide 2153 battery status information, and user-space programs will receive 2154 notification of APM "events" (e.g. battery status change). 2155 2156 If you select "Y" here, you can disable actual use of the APM 2157 BIOS by passing the "apm=off" option to the kernel at boot time. 2158 2159 Note that the APM support is almost completely disabled for 2160 machines with more than one CPU. 2161 2162 In order to use APM, you will need supporting software. For location 2163 and more information, read <file:Documentation/power/apm-acpi.txt> 2164 and the Battery Powered Linux mini-HOWTO, available from 2165 <http://www.tldp.org/docs.html#howto>. 2166 2167 This driver does not spin down disk drives (see the hdparm(8) 2168 manpage ("man 8 hdparm") for that), and it doesn't turn off 2169 VESA-compliant "green" monitors. 2170 2171 This driver does not support the TI 4000M TravelMate and the ACER 2172 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2173 desktop machines also don't have compliant BIOSes, and this driver 2174 may cause those machines to panic during the boot phase. 2175 2176 Generally, if you don't have a battery in your machine, there isn't 2177 much point in using this driver and you should say N. If you get 2178 random kernel OOPSes or reboots that don't seem to be related to 2179 anything, try disabling/enabling this option (or disabling/enabling 2180 APM in your BIOS). 2181 2182 Some other things you should try when experiencing seemingly random, 2183 "weird" problems: 2184 2185 1) make sure that you have enough swap space and that it is 2186 enabled. 2187 2) pass the "no-hlt" option to the kernel 2188 3) switch on floating point emulation in the kernel and pass 2189 the "no387" option to the kernel 2190 4) pass the "floppy=nodma" option to the kernel 2191 5) pass the "mem=4M" option to the kernel (thereby disabling 2192 all but the first 4 MB of RAM) 2193 6) make sure that the CPU is not over clocked. 2194 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2195 8) disable the cache from your BIOS settings 2196 9) install a fan for the video card or exchange video RAM 2197 10) install a better fan for the CPU 2198 11) exchange RAM chips 2199 12) exchange the motherboard. 2200 2201 To compile this driver as a module, choose M here: the 2202 module will be called apm. 2203 2204if APM 2205 2206config APM_IGNORE_USER_SUSPEND 2207 bool "Ignore USER SUSPEND" 2208 ---help--- 2209 This option will ignore USER SUSPEND requests. On machines with a 2210 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2211 series notebooks, it is necessary to say Y because of a BIOS bug. 2212 2213config APM_DO_ENABLE 2214 bool "Enable PM at boot time" 2215 ---help--- 2216 Enable APM features at boot time. From page 36 of the APM BIOS 2217 specification: "When disabled, the APM BIOS does not automatically 2218 power manage devices, enter the Standby State, enter the Suspend 2219 State, or take power saving steps in response to CPU Idle calls." 2220 This driver will make CPU Idle calls when Linux is idle (unless this 2221 feature is turned off -- see "Do CPU IDLE calls", below). This 2222 should always save battery power, but more complicated APM features 2223 will be dependent on your BIOS implementation. You may need to turn 2224 this option off if your computer hangs at boot time when using APM 2225 support, or if it beeps continuously instead of suspending. Turn 2226 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2227 T400CDT. This is off by default since most machines do fine without 2228 this feature. 2229 2230config APM_CPU_IDLE 2231 depends on CPU_IDLE 2232 bool "Make CPU Idle calls when idle" 2233 ---help--- 2234 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2235 On some machines, this can activate improved power savings, such as 2236 a slowed CPU clock rate, when the machine is idle. These idle calls 2237 are made after the idle loop has run for some length of time (e.g., 2238 333 mS). On some machines, this will cause a hang at boot time or 2239 whenever the CPU becomes idle. (On machines with more than one CPU, 2240 this option does nothing.) 2241 2242config APM_DISPLAY_BLANK 2243 bool "Enable console blanking using APM" 2244 ---help--- 2245 Enable console blanking using the APM. Some laptops can use this to 2246 turn off the LCD backlight when the screen blanker of the Linux 2247 virtual console blanks the screen. Note that this is only used by 2248 the virtual console screen blanker, and won't turn off the backlight 2249 when using the X Window system. This also doesn't have anything to 2250 do with your VESA-compliant power-saving monitor. Further, this 2251 option doesn't work for all laptops -- it might not turn off your 2252 backlight at all, or it might print a lot of errors to the console, 2253 especially if you are using gpm. 2254 2255config APM_ALLOW_INTS 2256 bool "Allow interrupts during APM BIOS calls" 2257 ---help--- 2258 Normally we disable external interrupts while we are making calls to 2259 the APM BIOS as a measure to lessen the effects of a badly behaving 2260 BIOS implementation. The BIOS should reenable interrupts if it 2261 needs to. Unfortunately, some BIOSes do not -- especially those in 2262 many of the newer IBM Thinkpads. If you experience hangs when you 2263 suspend, try setting this to Y. Otherwise, say N. 2264 2265endif # APM 2266 2267source "drivers/cpufreq/Kconfig" 2268 2269source "drivers/cpuidle/Kconfig" 2270 2271source "drivers/idle/Kconfig" 2272 2273endmenu 2274 2275 2276menu "Bus options (PCI etc.)" 2277 2278config PCI 2279 bool "PCI support" 2280 default y 2281 ---help--- 2282 Find out whether you have a PCI motherboard. PCI is the name of a 2283 bus system, i.e. the way the CPU talks to the other stuff inside 2284 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2285 VESA. If you have PCI, say Y, otherwise N. 2286 2287choice 2288 prompt "PCI access mode" 2289 depends on X86_32 && PCI 2290 default PCI_GOANY 2291 ---help--- 2292 On PCI systems, the BIOS can be used to detect the PCI devices and 2293 determine their configuration. However, some old PCI motherboards 2294 have BIOS bugs and may crash if this is done. Also, some embedded 2295 PCI-based systems don't have any BIOS at all. Linux can also try to 2296 detect the PCI hardware directly without using the BIOS. 2297 2298 With this option, you can specify how Linux should detect the 2299 PCI devices. If you choose "BIOS", the BIOS will be used, 2300 if you choose "Direct", the BIOS won't be used, and if you 2301 choose "MMConfig", then PCI Express MMCONFIG will be used. 2302 If you choose "Any", the kernel will try MMCONFIG, then the 2303 direct access method and falls back to the BIOS if that doesn't 2304 work. If unsure, go with the default, which is "Any". 2305 2306config PCI_GOBIOS 2307 bool "BIOS" 2308 2309config PCI_GOMMCONFIG 2310 bool "MMConfig" 2311 2312config PCI_GODIRECT 2313 bool "Direct" 2314 2315config PCI_GOOLPC 2316 bool "OLPC XO-1" 2317 depends on OLPC 2318 2319config PCI_GOANY 2320 bool "Any" 2321 2322endchoice 2323 2324config PCI_BIOS 2325 def_bool y 2326 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2327 2328# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2329config PCI_DIRECT 2330 def_bool y 2331 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2332 2333config PCI_MMCONFIG 2334 def_bool y 2335 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2336 2337config PCI_OLPC 2338 def_bool y 2339 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2340 2341config PCI_XEN 2342 def_bool y 2343 depends on PCI && XEN 2344 select SWIOTLB_XEN 2345 2346config PCI_DOMAINS 2347 def_bool y 2348 depends on PCI 2349 2350config PCI_MMCONFIG 2351 bool "Support mmconfig PCI config space access" 2352 depends on X86_64 && PCI && ACPI 2353 2354config PCI_CNB20LE_QUIRK 2355 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2356 depends on PCI 2357 help 2358 Read the PCI windows out of the CNB20LE host bridge. This allows 2359 PCI hotplug to work on systems with the CNB20LE chipset which do 2360 not have ACPI. 2361 2362 There's no public spec for this chipset, and this functionality 2363 is known to be incomplete. 2364 2365 You should say N unless you know you need this. 2366 2367source "drivers/pci/pcie/Kconfig" 2368 2369source "drivers/pci/Kconfig" 2370 2371# x86_64 have no ISA slots, but can have ISA-style DMA. 2372config ISA_DMA_API 2373 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2374 default y 2375 help 2376 Enables ISA-style DMA support for devices requiring such controllers. 2377 If unsure, say Y. 2378 2379if X86_32 2380 2381config ISA 2382 bool "ISA support" 2383 ---help--- 2384 Find out whether you have ISA slots on your motherboard. ISA is the 2385 name of a bus system, i.e. the way the CPU talks to the other stuff 2386 inside your box. Other bus systems are PCI, EISA, MicroChannel 2387 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2388 newer boards don't support it. If you have ISA, say Y, otherwise N. 2389 2390config EISA 2391 bool "EISA support" 2392 depends on ISA 2393 ---help--- 2394 The Extended Industry Standard Architecture (EISA) bus was 2395 developed as an open alternative to the IBM MicroChannel bus. 2396 2397 The EISA bus provided some of the features of the IBM MicroChannel 2398 bus while maintaining backward compatibility with cards made for 2399 the older ISA bus. The EISA bus saw limited use between 1988 and 2400 1995 when it was made obsolete by the PCI bus. 2401 2402 Say Y here if you are building a kernel for an EISA-based machine. 2403 2404 Otherwise, say N. 2405 2406source "drivers/eisa/Kconfig" 2407 2408config SCx200 2409 tristate "NatSemi SCx200 support" 2410 ---help--- 2411 This provides basic support for National Semiconductor's 2412 (now AMD's) Geode processors. The driver probes for the 2413 PCI-IDs of several on-chip devices, so its a good dependency 2414 for other scx200_* drivers. 2415 2416 If compiled as a module, the driver is named scx200. 2417 2418config SCx200HR_TIMER 2419 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2420 depends on SCx200 2421 default y 2422 ---help--- 2423 This driver provides a clocksource built upon the on-chip 2424 27MHz high-resolution timer. Its also a workaround for 2425 NSC Geode SC-1100's buggy TSC, which loses time when the 2426 processor goes idle (as is done by the scheduler). The 2427 other workaround is idle=poll boot option. 2428 2429config OLPC 2430 bool "One Laptop Per Child support" 2431 depends on !X86_PAE 2432 select GPIOLIB 2433 select OF 2434 select OF_PROMTREE 2435 select IRQ_DOMAIN 2436 ---help--- 2437 Add support for detecting the unique features of the OLPC 2438 XO hardware. 2439 2440config OLPC_XO1_PM 2441 bool "OLPC XO-1 Power Management" 2442 depends on OLPC && MFD_CS5535 && PM_SLEEP 2443 select MFD_CORE 2444 ---help--- 2445 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2446 2447config OLPC_XO1_RTC 2448 bool "OLPC XO-1 Real Time Clock" 2449 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2450 ---help--- 2451 Add support for the XO-1 real time clock, which can be used as a 2452 programmable wakeup source. 2453 2454config OLPC_XO1_SCI 2455 bool "OLPC XO-1 SCI extras" 2456 depends on OLPC && OLPC_XO1_PM 2457 depends on INPUT=y 2458 select POWER_SUPPLY 2459 select GPIO_CS5535 2460 select MFD_CORE 2461 ---help--- 2462 Add support for SCI-based features of the OLPC XO-1 laptop: 2463 - EC-driven system wakeups 2464 - Power button 2465 - Ebook switch 2466 - Lid switch 2467 - AC adapter status updates 2468 - Battery status updates 2469 2470config OLPC_XO15_SCI 2471 bool "OLPC XO-1.5 SCI extras" 2472 depends on OLPC && ACPI 2473 select POWER_SUPPLY 2474 ---help--- 2475 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2476 - EC-driven system wakeups 2477 - AC adapter status updates 2478 - Battery status updates 2479 2480config ALIX 2481 bool "PCEngines ALIX System Support (LED setup)" 2482 select GPIOLIB 2483 ---help--- 2484 This option enables system support for the PCEngines ALIX. 2485 At present this just sets up LEDs for GPIO control on 2486 ALIX2/3/6 boards. However, other system specific setup should 2487 get added here. 2488 2489 Note: You must still enable the drivers for GPIO and LED support 2490 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2491 2492 Note: You have to set alix.force=1 for boards with Award BIOS. 2493 2494config NET5501 2495 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2496 select GPIOLIB 2497 ---help--- 2498 This option enables system support for the Soekris Engineering net5501. 2499 2500config GEOS 2501 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2502 select GPIOLIB 2503 depends on DMI 2504 ---help--- 2505 This option enables system support for the Traverse Technologies GEOS. 2506 2507config TS5500 2508 bool "Technologic Systems TS-5500 platform support" 2509 depends on MELAN 2510 select CHECK_SIGNATURE 2511 select NEW_LEDS 2512 select LEDS_CLASS 2513 ---help--- 2514 This option enables system support for the Technologic Systems TS-5500. 2515 2516endif # X86_32 2517 2518config AMD_NB 2519 def_bool y 2520 depends on CPU_SUP_AMD && PCI 2521 2522source "drivers/pcmcia/Kconfig" 2523 2524source "drivers/pci/hotplug/Kconfig" 2525 2526config RAPIDIO 2527 tristate "RapidIO support" 2528 depends on PCI 2529 default n 2530 help 2531 If enabled this option will include drivers and the core 2532 infrastructure code to support RapidIO interconnect devices. 2533 2534source "drivers/rapidio/Kconfig" 2535 2536config X86_SYSFB 2537 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2538 help 2539 Firmwares often provide initial graphics framebuffers so the BIOS, 2540 bootloader or kernel can show basic video-output during boot for 2541 user-guidance and debugging. Historically, x86 used the VESA BIOS 2542 Extensions and EFI-framebuffers for this, which are mostly limited 2543 to x86. 2544 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2545 framebuffers so the new generic system-framebuffer drivers can be 2546 used on x86. If the framebuffer is not compatible with the generic 2547 modes, it is adverticed as fallback platform framebuffer so legacy 2548 drivers like efifb, vesafb and uvesafb can pick it up. 2549 If this option is not selected, all system framebuffers are always 2550 marked as fallback platform framebuffers as usual. 2551 2552 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2553 not be able to pick up generic system framebuffers if this option 2554 is selected. You are highly encouraged to enable simplefb as 2555 replacement if you select this option. simplefb can correctly deal 2556 with generic system framebuffers. But you should still keep vesafb 2557 and others enabled as fallback if a system framebuffer is 2558 incompatible with simplefb. 2559 2560 If unsure, say Y. 2561 2562endmenu 2563 2564 2565menu "Executable file formats / Emulations" 2566 2567source "fs/Kconfig.binfmt" 2568 2569config IA32_EMULATION 2570 bool "IA32 Emulation" 2571 depends on X86_64 2572 select BINFMT_ELF 2573 select COMPAT_BINFMT_ELF 2574 select ARCH_WANT_OLD_COMPAT_IPC 2575 ---help--- 2576 Include code to run legacy 32-bit programs under a 2577 64-bit kernel. You should likely turn this on, unless you're 2578 100% sure that you don't have any 32-bit programs left. 2579 2580config IA32_AOUT 2581 tristate "IA32 a.out support" 2582 depends on IA32_EMULATION 2583 ---help--- 2584 Support old a.out binaries in the 32bit emulation. 2585 2586config X86_X32 2587 bool "x32 ABI for 64-bit mode" 2588 depends on X86_64 2589 ---help--- 2590 Include code to run binaries for the x32 native 32-bit ABI 2591 for 64-bit processors. An x32 process gets access to the 2592 full 64-bit register file and wide data path while leaving 2593 pointers at 32 bits for smaller memory footprint. 2594 2595 You will need a recent binutils (2.22 or later) with 2596 elf32_x86_64 support enabled to compile a kernel with this 2597 option set. 2598 2599config COMPAT 2600 def_bool y 2601 depends on IA32_EMULATION || X86_X32 2602 2603if COMPAT 2604config COMPAT_FOR_U64_ALIGNMENT 2605 def_bool y 2606 2607config SYSVIPC_COMPAT 2608 def_bool y 2609 depends on SYSVIPC 2610 2611config KEYS_COMPAT 2612 def_bool y 2613 depends on KEYS 2614endif 2615 2616endmenu 2617 2618 2619config HAVE_ATOMIC_IOMAP 2620 def_bool y 2621 depends on X86_32 2622 2623config X86_DEV_DMA_OPS 2624 bool 2625 depends on X86_64 || STA2X11 2626 2627config X86_DMA_REMAP 2628 bool 2629 depends on STA2X11 2630 2631config PMC_ATOM 2632 def_bool y 2633 depends on PCI 2634 2635source "net/Kconfig" 2636 2637source "drivers/Kconfig" 2638 2639source "drivers/firmware/Kconfig" 2640 2641source "fs/Kconfig" 2642 2643source "arch/x86/Kconfig.debug" 2644 2645source "security/Kconfig" 2646 2647source "crypto/Kconfig" 2648 2649source "arch/x86/kvm/Kconfig" 2650 2651source "lib/Kconfig" 2652