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 ---help--- 1312 PAE is required for NX support, and furthermore enables 1313 larger swapspace support for non-overcommit purposes. It 1314 has the cost of more pagetable lookup overhead, and also 1315 consumes more pagetable space per process. 1316 1317config ARCH_PHYS_ADDR_T_64BIT 1318 def_bool y 1319 depends on X86_64 || X86_PAE 1320 1321config ARCH_DMA_ADDR_T_64BIT 1322 def_bool y 1323 depends on X86_64 || HIGHMEM64G 1324 1325config X86_DIRECT_GBPAGES 1326 def_bool y 1327 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1328 ---help--- 1329 Certain kernel features effectively disable kernel 1330 linear 1 GB mappings (even if the CPU otherwise 1331 supports them), so don't confuse the user by printing 1332 that we have them enabled. 1333 1334# Common NUMA Features 1335config NUMA 1336 bool "Numa Memory Allocation and Scheduler Support" 1337 depends on SMP 1338 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1339 default y if X86_BIGSMP 1340 ---help--- 1341 Enable NUMA (Non Uniform Memory Access) support. 1342 1343 The kernel will try to allocate memory used by a CPU on the 1344 local memory controller of the CPU and add some more 1345 NUMA awareness to the kernel. 1346 1347 For 64-bit this is recommended if the system is Intel Core i7 1348 (or later), AMD Opteron, or EM64T NUMA. 1349 1350 For 32-bit this is only needed if you boot a 32-bit 1351 kernel on a 64-bit NUMA platform. 1352 1353 Otherwise, you should say N. 1354 1355config AMD_NUMA 1356 def_bool y 1357 prompt "Old style AMD Opteron NUMA detection" 1358 depends on X86_64 && NUMA && PCI 1359 ---help--- 1360 Enable AMD NUMA node topology detection. You should say Y here if 1361 you have a multi processor AMD system. This uses an old method to 1362 read the NUMA configuration directly from the builtin Northbridge 1363 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1364 which also takes priority if both are compiled in. 1365 1366config X86_64_ACPI_NUMA 1367 def_bool y 1368 prompt "ACPI NUMA detection" 1369 depends on X86_64 && NUMA && ACPI && PCI 1370 select ACPI_NUMA 1371 ---help--- 1372 Enable ACPI SRAT based node topology detection. 1373 1374# Some NUMA nodes have memory ranges that span 1375# other nodes. Even though a pfn is valid and 1376# between a node's start and end pfns, it may not 1377# reside on that node. See memmap_init_zone() 1378# for details. 1379config NODES_SPAN_OTHER_NODES 1380 def_bool y 1381 depends on X86_64_ACPI_NUMA 1382 1383config NUMA_EMU 1384 bool "NUMA emulation" 1385 depends on NUMA 1386 ---help--- 1387 Enable NUMA emulation. A flat machine will be split 1388 into virtual nodes when booted with "numa=fake=N", where N is the 1389 number of nodes. This is only useful for debugging. 1390 1391config NODES_SHIFT 1392 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1393 range 1 10 1394 default "10" if MAXSMP 1395 default "6" if X86_64 1396 default "3" 1397 depends on NEED_MULTIPLE_NODES 1398 ---help--- 1399 Specify the maximum number of NUMA Nodes available on the target 1400 system. Increases memory reserved to accommodate various tables. 1401 1402config ARCH_HAVE_MEMORY_PRESENT 1403 def_bool y 1404 depends on X86_32 && DISCONTIGMEM 1405 1406config NEED_NODE_MEMMAP_SIZE 1407 def_bool y 1408 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1409 1410config ARCH_FLATMEM_ENABLE 1411 def_bool y 1412 depends on X86_32 && !NUMA 1413 1414config ARCH_DISCONTIGMEM_ENABLE 1415 def_bool y 1416 depends on NUMA && X86_32 1417 1418config ARCH_DISCONTIGMEM_DEFAULT 1419 def_bool y 1420 depends on NUMA && X86_32 1421 1422config ARCH_SPARSEMEM_ENABLE 1423 def_bool y 1424 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1425 select SPARSEMEM_STATIC if X86_32 1426 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1427 1428config ARCH_SPARSEMEM_DEFAULT 1429 def_bool y 1430 depends on X86_64 1431 1432config ARCH_SELECT_MEMORY_MODEL 1433 def_bool y 1434 depends on ARCH_SPARSEMEM_ENABLE 1435 1436config ARCH_MEMORY_PROBE 1437 bool "Enable sysfs memory/probe interface" 1438 depends on X86_64 && MEMORY_HOTPLUG 1439 help 1440 This option enables a sysfs memory/probe interface for testing. 1441 See Documentation/memory-hotplug.txt for more information. 1442 If you are unsure how to answer this question, answer N. 1443 1444config ARCH_PROC_KCORE_TEXT 1445 def_bool y 1446 depends on X86_64 && PROC_KCORE 1447 1448config ILLEGAL_POINTER_VALUE 1449 hex 1450 default 0 if X86_32 1451 default 0xdead000000000000 if X86_64 1452 1453source "mm/Kconfig" 1454 1455config X86_PMEM_LEGACY_DEVICE 1456 bool 1457 1458config X86_PMEM_LEGACY 1459 tristate "Support non-standard NVDIMMs and ADR protected memory" 1460 depends on PHYS_ADDR_T_64BIT 1461 depends on BLK_DEV 1462 select X86_PMEM_LEGACY_DEVICE 1463 select LIBNVDIMM 1464 help 1465 Treat memory marked using the non-standard e820 type of 12 as used 1466 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1467 The kernel will offer these regions to the 'pmem' driver so 1468 they can be used for persistent storage. 1469 1470 Say Y if unsure. 1471 1472config HIGHPTE 1473 bool "Allocate 3rd-level pagetables from highmem" 1474 depends on HIGHMEM 1475 ---help--- 1476 The VM uses one page table entry for each page of physical memory. 1477 For systems with a lot of RAM, this can be wasteful of precious 1478 low memory. Setting this option will put user-space page table 1479 entries in high memory. 1480 1481config X86_CHECK_BIOS_CORRUPTION 1482 bool "Check for low memory corruption" 1483 ---help--- 1484 Periodically check for memory corruption in low memory, which 1485 is suspected to be caused by BIOS. Even when enabled in the 1486 configuration, it is disabled at runtime. Enable it by 1487 setting "memory_corruption_check=1" on the kernel command 1488 line. By default it scans the low 64k of memory every 60 1489 seconds; see the memory_corruption_check_size and 1490 memory_corruption_check_period parameters in 1491 Documentation/kernel-parameters.txt to adjust this. 1492 1493 When enabled with the default parameters, this option has 1494 almost no overhead, as it reserves a relatively small amount 1495 of memory and scans it infrequently. It both detects corruption 1496 and prevents it from affecting the running system. 1497 1498 It is, however, intended as a diagnostic tool; if repeatable 1499 BIOS-originated corruption always affects the same memory, 1500 you can use memmap= to prevent the kernel from using that 1501 memory. 1502 1503config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1504 bool "Set the default setting of memory_corruption_check" 1505 depends on X86_CHECK_BIOS_CORRUPTION 1506 default y 1507 ---help--- 1508 Set whether the default state of memory_corruption_check is 1509 on or off. 1510 1511config X86_RESERVE_LOW 1512 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1513 default 64 1514 range 4 640 1515 ---help--- 1516 Specify the amount of low memory to reserve for the BIOS. 1517 1518 The first page contains BIOS data structures that the kernel 1519 must not use, so that page must always be reserved. 1520 1521 By default we reserve the first 64K of physical RAM, as a 1522 number of BIOSes are known to corrupt that memory range 1523 during events such as suspend/resume or monitor cable 1524 insertion, so it must not be used by the kernel. 1525 1526 You can set this to 4 if you are absolutely sure that you 1527 trust the BIOS to get all its memory reservations and usages 1528 right. If you know your BIOS have problems beyond the 1529 default 64K area, you can set this to 640 to avoid using the 1530 entire low memory range. 1531 1532 If you have doubts about the BIOS (e.g. suspend/resume does 1533 not work or there's kernel crashes after certain hardware 1534 hotplug events) then you might want to enable 1535 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1536 typical corruption patterns. 1537 1538 Leave this to the default value of 64 if you are unsure. 1539 1540config MATH_EMULATION 1541 bool 1542 depends on MODIFY_LDT_SYSCALL 1543 prompt "Math emulation" if X86_32 1544 ---help--- 1545 Linux can emulate a math coprocessor (used for floating point 1546 operations) if you don't have one. 486DX and Pentium processors have 1547 a math coprocessor built in, 486SX and 386 do not, unless you added 1548 a 487DX or 387, respectively. (The messages during boot time can 1549 give you some hints here ["man dmesg"].) Everyone needs either a 1550 coprocessor or this emulation. 1551 1552 If you don't have a math coprocessor, you need to say Y here; if you 1553 say Y here even though you have a coprocessor, the coprocessor will 1554 be used nevertheless. (This behavior can be changed with the kernel 1555 command line option "no387", which comes handy if your coprocessor 1556 is broken. Try "man bootparam" or see the documentation of your boot 1557 loader (lilo or loadlin) about how to pass options to the kernel at 1558 boot time.) This means that it is a good idea to say Y here if you 1559 intend to use this kernel on different machines. 1560 1561 More information about the internals of the Linux math coprocessor 1562 emulation can be found in <file:arch/x86/math-emu/README>. 1563 1564 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1565 kernel, it won't hurt. 1566 1567config MTRR 1568 def_bool y 1569 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1570 ---help--- 1571 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1572 the Memory Type Range Registers (MTRRs) may be used to control 1573 processor access to memory ranges. This is most useful if you have 1574 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1575 allows bus write transfers to be combined into a larger transfer 1576 before bursting over the PCI/AGP bus. This can increase performance 1577 of image write operations 2.5 times or more. Saying Y here creates a 1578 /proc/mtrr file which may be used to manipulate your processor's 1579 MTRRs. Typically the X server should use this. 1580 1581 This code has a reasonably generic interface so that similar 1582 control registers on other processors can be easily supported 1583 as well: 1584 1585 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1586 Registers (ARRs) which provide a similar functionality to MTRRs. For 1587 these, the ARRs are used to emulate the MTRRs. 1588 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1589 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1590 write-combining. All of these processors are supported by this code 1591 and it makes sense to say Y here if you have one of them. 1592 1593 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1594 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1595 can lead to all sorts of problems, so it's good to say Y here. 1596 1597 You can safely say Y even if your machine doesn't have MTRRs, you'll 1598 just add about 9 KB to your kernel. 1599 1600 See <file:Documentation/x86/mtrr.txt> for more information. 1601 1602config MTRR_SANITIZER 1603 def_bool y 1604 prompt "MTRR cleanup support" 1605 depends on MTRR 1606 ---help--- 1607 Convert MTRR layout from continuous to discrete, so X drivers can 1608 add writeback entries. 1609 1610 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1611 The largest mtrr entry size for a continuous block can be set with 1612 mtrr_chunk_size. 1613 1614 If unsure, say Y. 1615 1616config MTRR_SANITIZER_ENABLE_DEFAULT 1617 int "MTRR cleanup enable value (0-1)" 1618 range 0 1 1619 default "0" 1620 depends on MTRR_SANITIZER 1621 ---help--- 1622 Enable mtrr cleanup default value 1623 1624config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1625 int "MTRR cleanup spare reg num (0-7)" 1626 range 0 7 1627 default "1" 1628 depends on MTRR_SANITIZER 1629 ---help--- 1630 mtrr cleanup spare entries default, it can be changed via 1631 mtrr_spare_reg_nr=N on the kernel command line. 1632 1633config X86_PAT 1634 def_bool y 1635 prompt "x86 PAT support" if EXPERT 1636 depends on MTRR 1637 ---help--- 1638 Use PAT attributes to setup page level cache control. 1639 1640 PATs are the modern equivalents of MTRRs and are much more 1641 flexible than MTRRs. 1642 1643 Say N here if you see bootup problems (boot crash, boot hang, 1644 spontaneous reboots) or a non-working video driver. 1645 1646 If unsure, say Y. 1647 1648config ARCH_USES_PG_UNCACHED 1649 def_bool y 1650 depends on X86_PAT 1651 1652config ARCH_RANDOM 1653 def_bool y 1654 prompt "x86 architectural random number generator" if EXPERT 1655 ---help--- 1656 Enable the x86 architectural RDRAND instruction 1657 (Intel Bull Mountain technology) to generate random numbers. 1658 If supported, this is a high bandwidth, cryptographically 1659 secure hardware random number generator. 1660 1661config X86_SMAP 1662 def_bool y 1663 prompt "Supervisor Mode Access Prevention" if EXPERT 1664 ---help--- 1665 Supervisor Mode Access Prevention (SMAP) is a security 1666 feature in newer Intel processors. There is a small 1667 performance cost if this enabled and turned on; there is 1668 also a small increase in the kernel size if this is enabled. 1669 1670 If unsure, say Y. 1671 1672config X86_INTEL_MPX 1673 prompt "Intel MPX (Memory Protection Extensions)" 1674 def_bool n 1675 depends on CPU_SUP_INTEL 1676 ---help--- 1677 MPX provides hardware features that can be used in 1678 conjunction with compiler-instrumented code to check 1679 memory references. It is designed to detect buffer 1680 overflow or underflow bugs. 1681 1682 This option enables running applications which are 1683 instrumented or otherwise use MPX. It does not use MPX 1684 itself inside the kernel or to protect the kernel 1685 against bad memory references. 1686 1687 Enabling this option will make the kernel larger: 1688 ~8k of kernel text and 36 bytes of data on a 64-bit 1689 defconfig. It adds a long to the 'mm_struct' which 1690 will increase the kernel memory overhead of each 1691 process and adds some branches to paths used during 1692 exec() and munmap(). 1693 1694 For details, see Documentation/x86/intel_mpx.txt 1695 1696 If unsure, say N. 1697 1698config EFI 1699 bool "EFI runtime service support" 1700 depends on ACPI 1701 select UCS2_STRING 1702 select EFI_RUNTIME_WRAPPERS 1703 ---help--- 1704 This enables the kernel to use EFI runtime services that are 1705 available (such as the EFI variable services). 1706 1707 This option is only useful on systems that have EFI firmware. 1708 In addition, you should use the latest ELILO loader available 1709 at <http://elilo.sourceforge.net> in order to take advantage 1710 of EFI runtime services. However, even with this option, the 1711 resultant kernel should continue to boot on existing non-EFI 1712 platforms. 1713 1714config EFI_STUB 1715 bool "EFI stub support" 1716 depends on EFI && !X86_USE_3DNOW 1717 select RELOCATABLE 1718 ---help--- 1719 This kernel feature allows a bzImage to be loaded directly 1720 by EFI firmware without the use of a bootloader. 1721 1722 See Documentation/efi-stub.txt for more information. 1723 1724config EFI_MIXED 1725 bool "EFI mixed-mode support" 1726 depends on EFI_STUB && X86_64 1727 ---help--- 1728 Enabling this feature allows a 64-bit kernel to be booted 1729 on a 32-bit firmware, provided that your CPU supports 64-bit 1730 mode. 1731 1732 Note that it is not possible to boot a mixed-mode enabled 1733 kernel via the EFI boot stub - a bootloader that supports 1734 the EFI handover protocol must be used. 1735 1736 If unsure, say N. 1737 1738config SECCOMP 1739 def_bool y 1740 prompt "Enable seccomp to safely compute untrusted bytecode" 1741 ---help--- 1742 This kernel feature is useful for number crunching applications 1743 that may need to compute untrusted bytecode during their 1744 execution. By using pipes or other transports made available to 1745 the process as file descriptors supporting the read/write 1746 syscalls, it's possible to isolate those applications in 1747 their own address space using seccomp. Once seccomp is 1748 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1749 and the task is only allowed to execute a few safe syscalls 1750 defined by each seccomp mode. 1751 1752 If unsure, say Y. Only embedded should say N here. 1753 1754source kernel/Kconfig.hz 1755 1756config KEXEC 1757 bool "kexec system call" 1758 select KEXEC_CORE 1759 ---help--- 1760 kexec is a system call that implements the ability to shutdown your 1761 current kernel, and to start another kernel. It is like a reboot 1762 but it is independent of the system firmware. And like a reboot 1763 you can start any kernel with it, not just Linux. 1764 1765 The name comes from the similarity to the exec system call. 1766 1767 It is an ongoing process to be certain the hardware in a machine 1768 is properly shutdown, so do not be surprised if this code does not 1769 initially work for you. As of this writing the exact hardware 1770 interface is strongly in flux, so no good recommendation can be 1771 made. 1772 1773config KEXEC_FILE 1774 bool "kexec file based system call" 1775 select KEXEC_CORE 1776 select BUILD_BIN2C 1777 depends on X86_64 1778 depends on CRYPTO=y 1779 depends on CRYPTO_SHA256=y 1780 ---help--- 1781 This is new version of kexec system call. This system call is 1782 file based and takes file descriptors as system call argument 1783 for kernel and initramfs as opposed to list of segments as 1784 accepted by previous system call. 1785 1786config KEXEC_VERIFY_SIG 1787 bool "Verify kernel signature during kexec_file_load() syscall" 1788 depends on KEXEC_FILE 1789 ---help--- 1790 This option makes kernel signature verification mandatory for 1791 the kexec_file_load() syscall. 1792 1793 In addition to that option, you need to enable signature 1794 verification for the corresponding kernel image type being 1795 loaded in order for this to work. 1796 1797config KEXEC_BZIMAGE_VERIFY_SIG 1798 bool "Enable bzImage signature verification support" 1799 depends on KEXEC_VERIFY_SIG 1800 depends on SIGNED_PE_FILE_VERIFICATION 1801 select SYSTEM_TRUSTED_KEYRING 1802 ---help--- 1803 Enable bzImage signature verification support. 1804 1805config CRASH_DUMP 1806 bool "kernel crash dumps" 1807 depends on X86_64 || (X86_32 && HIGHMEM) 1808 ---help--- 1809 Generate crash dump after being started by kexec. 1810 This should be normally only set in special crash dump kernels 1811 which are loaded in the main kernel with kexec-tools into 1812 a specially reserved region and then later executed after 1813 a crash by kdump/kexec. The crash dump kernel must be compiled 1814 to a memory address not used by the main kernel or BIOS using 1815 PHYSICAL_START, or it must be built as a relocatable image 1816 (CONFIG_RELOCATABLE=y). 1817 For more details see Documentation/kdump/kdump.txt 1818 1819config KEXEC_JUMP 1820 bool "kexec jump" 1821 depends on KEXEC && HIBERNATION 1822 ---help--- 1823 Jump between original kernel and kexeced kernel and invoke 1824 code in physical address mode via KEXEC 1825 1826config PHYSICAL_START 1827 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1828 default "0x1000000" 1829 ---help--- 1830 This gives the physical address where the kernel is loaded. 1831 1832 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1833 bzImage will decompress itself to above physical address and 1834 run from there. Otherwise, bzImage will run from the address where 1835 it has been loaded by the boot loader and will ignore above physical 1836 address. 1837 1838 In normal kdump cases one does not have to set/change this option 1839 as now bzImage can be compiled as a completely relocatable image 1840 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1841 address. This option is mainly useful for the folks who don't want 1842 to use a bzImage for capturing the crash dump and want to use a 1843 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1844 to be specifically compiled to run from a specific memory area 1845 (normally a reserved region) and this option comes handy. 1846 1847 So if you are using bzImage for capturing the crash dump, 1848 leave the value here unchanged to 0x1000000 and set 1849 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1850 for capturing the crash dump change this value to start of 1851 the reserved region. In other words, it can be set based on 1852 the "X" value as specified in the "crashkernel=YM@XM" 1853 command line boot parameter passed to the panic-ed 1854 kernel. Please take a look at Documentation/kdump/kdump.txt 1855 for more details about crash dumps. 1856 1857 Usage of bzImage for capturing the crash dump is recommended as 1858 one does not have to build two kernels. Same kernel can be used 1859 as production kernel and capture kernel. Above option should have 1860 gone away after relocatable bzImage support is introduced. But it 1861 is present because there are users out there who continue to use 1862 vmlinux for dump capture. This option should go away down the 1863 line. 1864 1865 Don't change this unless you know what you are doing. 1866 1867config RELOCATABLE 1868 bool "Build a relocatable kernel" 1869 default y 1870 ---help--- 1871 This builds a kernel image that retains relocation information 1872 so it can be loaded someplace besides the default 1MB. 1873 The relocations tend to make the kernel binary about 10% larger, 1874 but are discarded at runtime. 1875 1876 One use is for the kexec on panic case where the recovery kernel 1877 must live at a different physical address than the primary 1878 kernel. 1879 1880 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1881 it has been loaded at and the compile time physical address 1882 (CONFIG_PHYSICAL_START) is used as the minimum location. 1883 1884config RANDOMIZE_BASE 1885 bool "Randomize the address of the kernel image" 1886 depends on RELOCATABLE 1887 default n 1888 ---help--- 1889 Randomizes the physical and virtual address at which the 1890 kernel image is decompressed, as a security feature that 1891 deters exploit attempts relying on knowledge of the location 1892 of kernel internals. 1893 1894 Entropy is generated using the RDRAND instruction if it is 1895 supported. If RDTSC is supported, it is used as well. If 1896 neither RDRAND nor RDTSC are supported, then randomness is 1897 read from the i8254 timer. 1898 1899 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1900 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1901 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1902 minimum of 2MiB, only 10 bits of entropy is theoretically 1903 possible. At best, due to page table layouts, 64-bit can use 1904 9 bits of entropy and 32-bit uses 8 bits. 1905 1906 If unsure, say N. 1907 1908config RANDOMIZE_BASE_MAX_OFFSET 1909 hex "Maximum kASLR offset allowed" if EXPERT 1910 depends on RANDOMIZE_BASE 1911 range 0x0 0x20000000 if X86_32 1912 default "0x20000000" if X86_32 1913 range 0x0 0x40000000 if X86_64 1914 default "0x40000000" if X86_64 1915 ---help--- 1916 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1917 memory is used to determine the maximal offset in bytes that will 1918 be applied to the kernel when kernel Address Space Layout 1919 Randomization (kASLR) is active. This must be a multiple of 1920 PHYSICAL_ALIGN. 1921 1922 On 32-bit this is limited to 512MiB by page table layouts. The 1923 default is 512MiB. 1924 1925 On 64-bit this is limited by how the kernel fixmap page table is 1926 positioned, so this cannot be larger than 1GiB currently. Without 1927 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1928 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1929 modules area will shrink to compensate, up to the current maximum 1930 1GiB to 1GiB split. The default is 1GiB. 1931 1932 If unsure, leave at the default value. 1933 1934# Relocation on x86 needs some additional build support 1935config X86_NEED_RELOCS 1936 def_bool y 1937 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1938 1939config PHYSICAL_ALIGN 1940 hex "Alignment value to which kernel should be aligned" 1941 default "0x200000" 1942 range 0x2000 0x1000000 if X86_32 1943 range 0x200000 0x1000000 if X86_64 1944 ---help--- 1945 This value puts the alignment restrictions on physical address 1946 where kernel is loaded and run from. Kernel is compiled for an 1947 address which meets above alignment restriction. 1948 1949 If bootloader loads the kernel at a non-aligned address and 1950 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1951 address aligned to above value and run from there. 1952 1953 If bootloader loads the kernel at a non-aligned address and 1954 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1955 load address and decompress itself to the address it has been 1956 compiled for and run from there. The address for which kernel is 1957 compiled already meets above alignment restrictions. Hence the 1958 end result is that kernel runs from a physical address meeting 1959 above alignment restrictions. 1960 1961 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1962 this value must be a multiple of 0x200000. 1963 1964 Don't change this unless you know what you are doing. 1965 1966config HOTPLUG_CPU 1967 bool "Support for hot-pluggable CPUs" 1968 depends on SMP 1969 ---help--- 1970 Say Y here to allow turning CPUs off and on. CPUs can be 1971 controlled through /sys/devices/system/cpu. 1972 ( Note: power management support will enable this option 1973 automatically on SMP systems. ) 1974 Say N if you want to disable CPU hotplug. 1975 1976config BOOTPARAM_HOTPLUG_CPU0 1977 bool "Set default setting of cpu0_hotpluggable" 1978 default n 1979 depends on HOTPLUG_CPU 1980 ---help--- 1981 Set whether default state of cpu0_hotpluggable is on or off. 1982 1983 Say Y here to enable CPU0 hotplug by default. If this switch 1984 is turned on, there is no need to give cpu0_hotplug kernel 1985 parameter and the CPU0 hotplug feature is enabled by default. 1986 1987 Please note: there are two known CPU0 dependencies if you want 1988 to enable the CPU0 hotplug feature either by this switch or by 1989 cpu0_hotplug kernel parameter. 1990 1991 First, resume from hibernate or suspend always starts from CPU0. 1992 So hibernate and suspend are prevented if CPU0 is offline. 1993 1994 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1995 offline if any interrupt can not migrate out of CPU0. There may 1996 be other CPU0 dependencies. 1997 1998 Please make sure the dependencies are under your control before 1999 you enable this feature. 2000 2001 Say N if you don't want to enable CPU0 hotplug feature by default. 2002 You still can enable the CPU0 hotplug feature at boot by kernel 2003 parameter cpu0_hotplug. 2004 2005config DEBUG_HOTPLUG_CPU0 2006 def_bool n 2007 prompt "Debug CPU0 hotplug" 2008 depends on HOTPLUG_CPU 2009 ---help--- 2010 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2011 soon as possible and boots up userspace with CPU0 offlined. User 2012 can online CPU0 back after boot time. 2013 2014 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2015 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2016 compilation or giving cpu0_hotplug kernel parameter at boot. 2017 2018 If unsure, say N. 2019 2020config COMPAT_VDSO 2021 def_bool n 2022 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2023 depends on X86_32 || IA32_EMULATION 2024 ---help--- 2025 Certain buggy versions of glibc will crash if they are 2026 presented with a 32-bit vDSO that is not mapped at the address 2027 indicated in its segment table. 2028 2029 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2030 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2031 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2032 the only released version with the bug, but OpenSUSE 9 2033 contains a buggy "glibc 2.3.2". 2034 2035 The symptom of the bug is that everything crashes on startup, saying: 2036 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2037 2038 Saying Y here changes the default value of the vdso32 boot 2039 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2040 This works around the glibc bug but hurts performance. 2041 2042 If unsure, say N: if you are compiling your own kernel, you 2043 are unlikely to be using a buggy version of glibc. 2044 2045config CMDLINE_BOOL 2046 bool "Built-in kernel command line" 2047 ---help--- 2048 Allow for specifying boot arguments to the kernel at 2049 build time. On some systems (e.g. embedded ones), it is 2050 necessary or convenient to provide some or all of the 2051 kernel boot arguments with the kernel itself (that is, 2052 to not rely on the boot loader to provide them.) 2053 2054 To compile command line arguments into the kernel, 2055 set this option to 'Y', then fill in the 2056 boot arguments in CONFIG_CMDLINE. 2057 2058 Systems with fully functional boot loaders (i.e. non-embedded) 2059 should leave this option set to 'N'. 2060 2061config CMDLINE 2062 string "Built-in kernel command string" 2063 depends on CMDLINE_BOOL 2064 default "" 2065 ---help--- 2066 Enter arguments here that should be compiled into the kernel 2067 image and used at boot time. If the boot loader provides a 2068 command line at boot time, it is appended to this string to 2069 form the full kernel command line, when the system boots. 2070 2071 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2072 change this behavior. 2073 2074 In most cases, the command line (whether built-in or provided 2075 by the boot loader) should specify the device for the root 2076 file system. 2077 2078config CMDLINE_OVERRIDE 2079 bool "Built-in command line overrides boot loader arguments" 2080 depends on CMDLINE_BOOL 2081 ---help--- 2082 Set this option to 'Y' to have the kernel ignore the boot loader 2083 command line, and use ONLY the built-in command line. 2084 2085 This is used to work around broken boot loaders. This should 2086 be set to 'N' under normal conditions. 2087 2088config MODIFY_LDT_SYSCALL 2089 bool "Enable the LDT (local descriptor table)" if EXPERT 2090 default y 2091 ---help--- 2092 Linux can allow user programs to install a per-process x86 2093 Local Descriptor Table (LDT) using the modify_ldt(2) system 2094 call. This is required to run 16-bit or segmented code such as 2095 DOSEMU or some Wine programs. It is also used by some very old 2096 threading libraries. 2097 2098 Enabling this feature adds a small amount of overhead to 2099 context switches and increases the low-level kernel attack 2100 surface. Disabling it removes the modify_ldt(2) system call. 2101 2102 Saying 'N' here may make sense for embedded or server kernels. 2103 2104source "kernel/livepatch/Kconfig" 2105 2106endmenu 2107 2108config ARCH_ENABLE_MEMORY_HOTPLUG 2109 def_bool y 2110 depends on X86_64 || (X86_32 && HIGHMEM) 2111 2112config ARCH_ENABLE_MEMORY_HOTREMOVE 2113 def_bool y 2114 depends on MEMORY_HOTPLUG 2115 2116config USE_PERCPU_NUMA_NODE_ID 2117 def_bool y 2118 depends on NUMA 2119 2120config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2121 def_bool y 2122 depends on X86_64 || X86_PAE 2123 2124config ARCH_ENABLE_HUGEPAGE_MIGRATION 2125 def_bool y 2126 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2127 2128menu "Power management and ACPI options" 2129 2130config ARCH_HIBERNATION_HEADER 2131 def_bool y 2132 depends on X86_64 && HIBERNATION 2133 2134source "kernel/power/Kconfig" 2135 2136source "drivers/acpi/Kconfig" 2137 2138source "drivers/sfi/Kconfig" 2139 2140config X86_APM_BOOT 2141 def_bool y 2142 depends on APM 2143 2144menuconfig APM 2145 tristate "APM (Advanced Power Management) BIOS support" 2146 depends on X86_32 && PM_SLEEP 2147 ---help--- 2148 APM is a BIOS specification for saving power using several different 2149 techniques. This is mostly useful for battery powered laptops with 2150 APM compliant BIOSes. If you say Y here, the system time will be 2151 reset after a RESUME operation, the /proc/apm device will provide 2152 battery status information, and user-space programs will receive 2153 notification of APM "events" (e.g. battery status change). 2154 2155 If you select "Y" here, you can disable actual use of the APM 2156 BIOS by passing the "apm=off" option to the kernel at boot time. 2157 2158 Note that the APM support is almost completely disabled for 2159 machines with more than one CPU. 2160 2161 In order to use APM, you will need supporting software. For location 2162 and more information, read <file:Documentation/power/apm-acpi.txt> 2163 and the Battery Powered Linux mini-HOWTO, available from 2164 <http://www.tldp.org/docs.html#howto>. 2165 2166 This driver does not spin down disk drives (see the hdparm(8) 2167 manpage ("man 8 hdparm") for that), and it doesn't turn off 2168 VESA-compliant "green" monitors. 2169 2170 This driver does not support the TI 4000M TravelMate and the ACER 2171 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2172 desktop machines also don't have compliant BIOSes, and this driver 2173 may cause those machines to panic during the boot phase. 2174 2175 Generally, if you don't have a battery in your machine, there isn't 2176 much point in using this driver and you should say N. If you get 2177 random kernel OOPSes or reboots that don't seem to be related to 2178 anything, try disabling/enabling this option (or disabling/enabling 2179 APM in your BIOS). 2180 2181 Some other things you should try when experiencing seemingly random, 2182 "weird" problems: 2183 2184 1) make sure that you have enough swap space and that it is 2185 enabled. 2186 2) pass the "no-hlt" option to the kernel 2187 3) switch on floating point emulation in the kernel and pass 2188 the "no387" option to the kernel 2189 4) pass the "floppy=nodma" option to the kernel 2190 5) pass the "mem=4M" option to the kernel (thereby disabling 2191 all but the first 4 MB of RAM) 2192 6) make sure that the CPU is not over clocked. 2193 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2194 8) disable the cache from your BIOS settings 2195 9) install a fan for the video card or exchange video RAM 2196 10) install a better fan for the CPU 2197 11) exchange RAM chips 2198 12) exchange the motherboard. 2199 2200 To compile this driver as a module, choose M here: the 2201 module will be called apm. 2202 2203if APM 2204 2205config APM_IGNORE_USER_SUSPEND 2206 bool "Ignore USER SUSPEND" 2207 ---help--- 2208 This option will ignore USER SUSPEND requests. On machines with a 2209 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2210 series notebooks, it is necessary to say Y because of a BIOS bug. 2211 2212config APM_DO_ENABLE 2213 bool "Enable PM at boot time" 2214 ---help--- 2215 Enable APM features at boot time. From page 36 of the APM BIOS 2216 specification: "When disabled, the APM BIOS does not automatically 2217 power manage devices, enter the Standby State, enter the Suspend 2218 State, or take power saving steps in response to CPU Idle calls." 2219 This driver will make CPU Idle calls when Linux is idle (unless this 2220 feature is turned off -- see "Do CPU IDLE calls", below). This 2221 should always save battery power, but more complicated APM features 2222 will be dependent on your BIOS implementation. You may need to turn 2223 this option off if your computer hangs at boot time when using APM 2224 support, or if it beeps continuously instead of suspending. Turn 2225 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2226 T400CDT. This is off by default since most machines do fine without 2227 this feature. 2228 2229config APM_CPU_IDLE 2230 depends on CPU_IDLE 2231 bool "Make CPU Idle calls when idle" 2232 ---help--- 2233 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2234 On some machines, this can activate improved power savings, such as 2235 a slowed CPU clock rate, when the machine is idle. These idle calls 2236 are made after the idle loop has run for some length of time (e.g., 2237 333 mS). On some machines, this will cause a hang at boot time or 2238 whenever the CPU becomes idle. (On machines with more than one CPU, 2239 this option does nothing.) 2240 2241config APM_DISPLAY_BLANK 2242 bool "Enable console blanking using APM" 2243 ---help--- 2244 Enable console blanking using the APM. Some laptops can use this to 2245 turn off the LCD backlight when the screen blanker of the Linux 2246 virtual console blanks the screen. Note that this is only used by 2247 the virtual console screen blanker, and won't turn off the backlight 2248 when using the X Window system. This also doesn't have anything to 2249 do with your VESA-compliant power-saving monitor. Further, this 2250 option doesn't work for all laptops -- it might not turn off your 2251 backlight at all, or it might print a lot of errors to the console, 2252 especially if you are using gpm. 2253 2254config APM_ALLOW_INTS 2255 bool "Allow interrupts during APM BIOS calls" 2256 ---help--- 2257 Normally we disable external interrupts while we are making calls to 2258 the APM BIOS as a measure to lessen the effects of a badly behaving 2259 BIOS implementation. The BIOS should reenable interrupts if it 2260 needs to. Unfortunately, some BIOSes do not -- especially those in 2261 many of the newer IBM Thinkpads. If you experience hangs when you 2262 suspend, try setting this to Y. Otherwise, say N. 2263 2264endif # APM 2265 2266source "drivers/cpufreq/Kconfig" 2267 2268source "drivers/cpuidle/Kconfig" 2269 2270source "drivers/idle/Kconfig" 2271 2272endmenu 2273 2274 2275menu "Bus options (PCI etc.)" 2276 2277config PCI 2278 bool "PCI support" 2279 default y 2280 ---help--- 2281 Find out whether you have a PCI motherboard. PCI is the name of a 2282 bus system, i.e. the way the CPU talks to the other stuff inside 2283 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2284 VESA. If you have PCI, say Y, otherwise N. 2285 2286choice 2287 prompt "PCI access mode" 2288 depends on X86_32 && PCI 2289 default PCI_GOANY 2290 ---help--- 2291 On PCI systems, the BIOS can be used to detect the PCI devices and 2292 determine their configuration. However, some old PCI motherboards 2293 have BIOS bugs and may crash if this is done. Also, some embedded 2294 PCI-based systems don't have any BIOS at all. Linux can also try to 2295 detect the PCI hardware directly without using the BIOS. 2296 2297 With this option, you can specify how Linux should detect the 2298 PCI devices. If you choose "BIOS", the BIOS will be used, 2299 if you choose "Direct", the BIOS won't be used, and if you 2300 choose "MMConfig", then PCI Express MMCONFIG will be used. 2301 If you choose "Any", the kernel will try MMCONFIG, then the 2302 direct access method and falls back to the BIOS if that doesn't 2303 work. If unsure, go with the default, which is "Any". 2304 2305config PCI_GOBIOS 2306 bool "BIOS" 2307 2308config PCI_GOMMCONFIG 2309 bool "MMConfig" 2310 2311config PCI_GODIRECT 2312 bool "Direct" 2313 2314config PCI_GOOLPC 2315 bool "OLPC XO-1" 2316 depends on OLPC 2317 2318config PCI_GOANY 2319 bool "Any" 2320 2321endchoice 2322 2323config PCI_BIOS 2324 def_bool y 2325 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2326 2327# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2328config PCI_DIRECT 2329 def_bool y 2330 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2331 2332config PCI_MMCONFIG 2333 def_bool y 2334 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2335 2336config PCI_OLPC 2337 def_bool y 2338 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2339 2340config PCI_XEN 2341 def_bool y 2342 depends on PCI && XEN 2343 select SWIOTLB_XEN 2344 2345config PCI_DOMAINS 2346 def_bool y 2347 depends on PCI 2348 2349config PCI_MMCONFIG 2350 bool "Support mmconfig PCI config space access" 2351 depends on X86_64 && PCI && ACPI 2352 2353config PCI_CNB20LE_QUIRK 2354 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2355 depends on PCI 2356 help 2357 Read the PCI windows out of the CNB20LE host bridge. This allows 2358 PCI hotplug to work on systems with the CNB20LE chipset which do 2359 not have ACPI. 2360 2361 There's no public spec for this chipset, and this functionality 2362 is known to be incomplete. 2363 2364 You should say N unless you know you need this. 2365 2366source "drivers/pci/pcie/Kconfig" 2367 2368source "drivers/pci/Kconfig" 2369 2370# x86_64 have no ISA slots, but can have ISA-style DMA. 2371config ISA_DMA_API 2372 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2373 default y 2374 help 2375 Enables ISA-style DMA support for devices requiring such controllers. 2376 If unsure, say Y. 2377 2378if X86_32 2379 2380config ISA 2381 bool "ISA support" 2382 ---help--- 2383 Find out whether you have ISA slots on your motherboard. ISA is the 2384 name of a bus system, i.e. the way the CPU talks to the other stuff 2385 inside your box. Other bus systems are PCI, EISA, MicroChannel 2386 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2387 newer boards don't support it. If you have ISA, say Y, otherwise N. 2388 2389config EISA 2390 bool "EISA support" 2391 depends on ISA 2392 ---help--- 2393 The Extended Industry Standard Architecture (EISA) bus was 2394 developed as an open alternative to the IBM MicroChannel bus. 2395 2396 The EISA bus provided some of the features of the IBM MicroChannel 2397 bus while maintaining backward compatibility with cards made for 2398 the older ISA bus. The EISA bus saw limited use between 1988 and 2399 1995 when it was made obsolete by the PCI bus. 2400 2401 Say Y here if you are building a kernel for an EISA-based machine. 2402 2403 Otherwise, say N. 2404 2405source "drivers/eisa/Kconfig" 2406 2407config SCx200 2408 tristate "NatSemi SCx200 support" 2409 ---help--- 2410 This provides basic support for National Semiconductor's 2411 (now AMD's) Geode processors. The driver probes for the 2412 PCI-IDs of several on-chip devices, so its a good dependency 2413 for other scx200_* drivers. 2414 2415 If compiled as a module, the driver is named scx200. 2416 2417config SCx200HR_TIMER 2418 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2419 depends on SCx200 2420 default y 2421 ---help--- 2422 This driver provides a clocksource built upon the on-chip 2423 27MHz high-resolution timer. Its also a workaround for 2424 NSC Geode SC-1100's buggy TSC, which loses time when the 2425 processor goes idle (as is done by the scheduler). The 2426 other workaround is idle=poll boot option. 2427 2428config OLPC 2429 bool "One Laptop Per Child support" 2430 depends on !X86_PAE 2431 select GPIOLIB 2432 select OF 2433 select OF_PROMTREE 2434 select IRQ_DOMAIN 2435 ---help--- 2436 Add support for detecting the unique features of the OLPC 2437 XO hardware. 2438 2439config OLPC_XO1_PM 2440 bool "OLPC XO-1 Power Management" 2441 depends on OLPC && MFD_CS5535 && PM_SLEEP 2442 select MFD_CORE 2443 ---help--- 2444 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2445 2446config OLPC_XO1_RTC 2447 bool "OLPC XO-1 Real Time Clock" 2448 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2449 ---help--- 2450 Add support for the XO-1 real time clock, which can be used as a 2451 programmable wakeup source. 2452 2453config OLPC_XO1_SCI 2454 bool "OLPC XO-1 SCI extras" 2455 depends on OLPC && OLPC_XO1_PM 2456 depends on INPUT=y 2457 select POWER_SUPPLY 2458 select GPIO_CS5535 2459 select MFD_CORE 2460 ---help--- 2461 Add support for SCI-based features of the OLPC XO-1 laptop: 2462 - EC-driven system wakeups 2463 - Power button 2464 - Ebook switch 2465 - Lid switch 2466 - AC adapter status updates 2467 - Battery status updates 2468 2469config OLPC_XO15_SCI 2470 bool "OLPC XO-1.5 SCI extras" 2471 depends on OLPC && ACPI 2472 select POWER_SUPPLY 2473 ---help--- 2474 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2475 - EC-driven system wakeups 2476 - AC adapter status updates 2477 - Battery status updates 2478 2479config ALIX 2480 bool "PCEngines ALIX System Support (LED setup)" 2481 select GPIOLIB 2482 ---help--- 2483 This option enables system support for the PCEngines ALIX. 2484 At present this just sets up LEDs for GPIO control on 2485 ALIX2/3/6 boards. However, other system specific setup should 2486 get added here. 2487 2488 Note: You must still enable the drivers for GPIO and LED support 2489 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2490 2491 Note: You have to set alix.force=1 for boards with Award BIOS. 2492 2493config NET5501 2494 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2495 select GPIOLIB 2496 ---help--- 2497 This option enables system support for the Soekris Engineering net5501. 2498 2499config GEOS 2500 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2501 select GPIOLIB 2502 depends on DMI 2503 ---help--- 2504 This option enables system support for the Traverse Technologies GEOS. 2505 2506config TS5500 2507 bool "Technologic Systems TS-5500 platform support" 2508 depends on MELAN 2509 select CHECK_SIGNATURE 2510 select NEW_LEDS 2511 select LEDS_CLASS 2512 ---help--- 2513 This option enables system support for the Technologic Systems TS-5500. 2514 2515endif # X86_32 2516 2517config AMD_NB 2518 def_bool y 2519 depends on CPU_SUP_AMD && PCI 2520 2521source "drivers/pcmcia/Kconfig" 2522 2523source "drivers/pci/hotplug/Kconfig" 2524 2525config RAPIDIO 2526 tristate "RapidIO support" 2527 depends on PCI 2528 default n 2529 help 2530 If enabled this option will include drivers and the core 2531 infrastructure code to support RapidIO interconnect devices. 2532 2533source "drivers/rapidio/Kconfig" 2534 2535config X86_SYSFB 2536 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2537 help 2538 Firmwares often provide initial graphics framebuffers so the BIOS, 2539 bootloader or kernel can show basic video-output during boot for 2540 user-guidance and debugging. Historically, x86 used the VESA BIOS 2541 Extensions and EFI-framebuffers for this, which are mostly limited 2542 to x86. 2543 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2544 framebuffers so the new generic system-framebuffer drivers can be 2545 used on x86. If the framebuffer is not compatible with the generic 2546 modes, it is adverticed as fallback platform framebuffer so legacy 2547 drivers like efifb, vesafb and uvesafb can pick it up. 2548 If this option is not selected, all system framebuffers are always 2549 marked as fallback platform framebuffers as usual. 2550 2551 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2552 not be able to pick up generic system framebuffers if this option 2553 is selected. You are highly encouraged to enable simplefb as 2554 replacement if you select this option. simplefb can correctly deal 2555 with generic system framebuffers. But you should still keep vesafb 2556 and others enabled as fallback if a system framebuffer is 2557 incompatible with simplefb. 2558 2559 If unsure, say Y. 2560 2561endmenu 2562 2563 2564menu "Executable file formats / Emulations" 2565 2566source "fs/Kconfig.binfmt" 2567 2568config IA32_EMULATION 2569 bool "IA32 Emulation" 2570 depends on X86_64 2571 select BINFMT_ELF 2572 select COMPAT_BINFMT_ELF 2573 select ARCH_WANT_OLD_COMPAT_IPC 2574 ---help--- 2575 Include code to run legacy 32-bit programs under a 2576 64-bit kernel. You should likely turn this on, unless you're 2577 100% sure that you don't have any 32-bit programs left. 2578 2579config IA32_AOUT 2580 tristate "IA32 a.out support" 2581 depends on IA32_EMULATION 2582 ---help--- 2583 Support old a.out binaries in the 32bit emulation. 2584 2585config X86_X32 2586 bool "x32 ABI for 64-bit mode" 2587 depends on X86_64 2588 ---help--- 2589 Include code to run binaries for the x32 native 32-bit ABI 2590 for 64-bit processors. An x32 process gets access to the 2591 full 64-bit register file and wide data path while leaving 2592 pointers at 32 bits for smaller memory footprint. 2593 2594 You will need a recent binutils (2.22 or later) with 2595 elf32_x86_64 support enabled to compile a kernel with this 2596 option set. 2597 2598config COMPAT 2599 def_bool y 2600 depends on IA32_EMULATION || X86_X32 2601 2602if COMPAT 2603config COMPAT_FOR_U64_ALIGNMENT 2604 def_bool y 2605 2606config SYSVIPC_COMPAT 2607 def_bool y 2608 depends on SYSVIPC 2609 2610config KEYS_COMPAT 2611 def_bool y 2612 depends on KEYS 2613endif 2614 2615endmenu 2616 2617 2618config HAVE_ATOMIC_IOMAP 2619 def_bool y 2620 depends on X86_32 2621 2622config X86_DEV_DMA_OPS 2623 bool 2624 depends on X86_64 || STA2X11 2625 2626config X86_DMA_REMAP 2627 bool 2628 depends on STA2X11 2629 2630config PMC_ATOM 2631 def_bool y 2632 depends on PCI 2633 2634source "net/Kconfig" 2635 2636source "drivers/Kconfig" 2637 2638source "drivers/firmware/Kconfig" 2639 2640source "fs/Kconfig" 2641 2642source "arch/x86/Kconfig.debug" 2643 2644source "security/Kconfig" 2645 2646source "crypto/Kconfig" 2647 2648source "arch/x86/kvm/Kconfig" 2649 2650source "lib/Kconfig" 2651