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 (obsolete)" 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 (pretty well performing) software emulation. 1022 1023 Anything that works on a 64-bit kernel is unlikely to need 1024 this option, as 64-bit kernels don't, and can't, support V8086 1025 mode. This option is also unrelated to 16-bit protected mode 1026 and is not needed to run most 16-bit programs under Wine. 1027 1028 Enabling this option adds considerable attack surface to the 1029 kernel and slows down system calls and exception handling. 1030 1031 Unless you use very old userspace or need the last drop of 1032 performance in your real mode DOS games and can't use KVM, 1033 say N here. 1034 1035config VM86 1036 bool 1037 default X86_LEGACY_VM86 1038 1039config X86_16BIT 1040 bool "Enable support for 16-bit segments" if EXPERT 1041 default y 1042 depends on MODIFY_LDT_SYSCALL 1043 ---help--- 1044 This option is required by programs like Wine to run 16-bit 1045 protected mode legacy code on x86 processors. Disabling 1046 this option saves about 300 bytes on i386, or around 6K text 1047 plus 16K runtime memory on x86-64, 1048 1049config X86_ESPFIX32 1050 def_bool y 1051 depends on X86_16BIT && X86_32 1052 1053config X86_ESPFIX64 1054 def_bool y 1055 depends on X86_16BIT && X86_64 1056 1057config X86_VSYSCALL_EMULATION 1058 bool "Enable vsyscall emulation" if EXPERT 1059 default y 1060 depends on X86_64 1061 ---help--- 1062 This enables emulation of the legacy vsyscall page. Disabling 1063 it is roughly equivalent to booting with vsyscall=none, except 1064 that it will also disable the helpful warning if a program 1065 tries to use a vsyscall. With this option set to N, offending 1066 programs will just segfault, citing addresses of the form 1067 0xffffffffff600?00. 1068 1069 This option is required by many programs built before 2013, and 1070 care should be used even with newer programs if set to N. 1071 1072 Disabling this option saves about 7K of kernel size and 1073 possibly 4K of additional runtime pagetable memory. 1074 1075config TOSHIBA 1076 tristate "Toshiba Laptop support" 1077 depends on X86_32 1078 ---help--- 1079 This adds a driver to safely access the System Management Mode of 1080 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1081 not work on models with a Phoenix BIOS. The System Management Mode 1082 is used to set the BIOS and power saving options on Toshiba portables. 1083 1084 For information on utilities to make use of this driver see the 1085 Toshiba Linux utilities web site at: 1086 <http://www.buzzard.org.uk/toshiba/>. 1087 1088 Say Y if you intend to run this kernel on a Toshiba portable. 1089 Say N otherwise. 1090 1091config I8K 1092 tristate "Dell i8k legacy laptop support" 1093 select HWMON 1094 select SENSORS_DELL_SMM 1095 ---help--- 1096 This option enables legacy /proc/i8k userspace interface in hwmon 1097 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1098 temperature and allows controlling fan speeds of Dell laptops via 1099 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1100 it reports also power and hotkey status. For fan speed control is 1101 needed userspace package i8kutils. 1102 1103 Say Y if you intend to run this kernel on old Dell laptops or want to 1104 use userspace package i8kutils. 1105 Say N otherwise. 1106 1107config X86_REBOOTFIXUPS 1108 bool "Enable X86 board specific fixups for reboot" 1109 depends on X86_32 1110 ---help--- 1111 This enables chipset and/or board specific fixups to be done 1112 in order to get reboot to work correctly. This is only needed on 1113 some combinations of hardware and BIOS. The symptom, for which 1114 this config is intended, is when reboot ends with a stalled/hung 1115 system. 1116 1117 Currently, the only fixup is for the Geode machines using 1118 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1119 1120 Say Y if you want to enable the fixup. Currently, it's safe to 1121 enable this option even if you don't need it. 1122 Say N otherwise. 1123 1124config MICROCODE 1125 tristate "CPU microcode loading support" 1126 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1127 select FW_LOADER 1128 ---help--- 1129 1130 If you say Y here, you will be able to update the microcode on 1131 certain Intel and AMD processors. The Intel support is for the 1132 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1133 Xeon etc. The AMD support is for families 0x10 and later. You will 1134 obviously need the actual microcode binary data itself which is not 1135 shipped with the Linux kernel. 1136 1137 This option selects the general module only, you need to select 1138 at least one vendor specific module as well. 1139 1140 To compile this driver as a module, choose M here: the module 1141 will be called microcode. 1142 1143config MICROCODE_INTEL 1144 bool "Intel microcode loading support" 1145 depends on MICROCODE 1146 default MICROCODE 1147 select FW_LOADER 1148 ---help--- 1149 This options enables microcode patch loading support for Intel 1150 processors. 1151 1152 For the current Intel microcode data package go to 1153 <https://downloadcenter.intel.com> and search for 1154 'Linux Processor Microcode Data File'. 1155 1156config MICROCODE_AMD 1157 bool "AMD microcode loading support" 1158 depends on MICROCODE 1159 select FW_LOADER 1160 ---help--- 1161 If you select this option, microcode patch loading support for AMD 1162 processors will be enabled. 1163 1164config MICROCODE_OLD_INTERFACE 1165 def_bool y 1166 depends on MICROCODE 1167 1168config MICROCODE_INTEL_EARLY 1169 bool 1170 1171config MICROCODE_AMD_EARLY 1172 bool 1173 1174config MICROCODE_EARLY 1175 bool "Early load microcode" 1176 depends on MICROCODE=y && BLK_DEV_INITRD 1177 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1178 select MICROCODE_AMD_EARLY if MICROCODE_AMD 1179 default y 1180 help 1181 This option provides functionality to read additional microcode data 1182 at the beginning of initrd image. The data tells kernel to load 1183 microcode to CPU's as early as possible. No functional change if no 1184 microcode data is glued to the initrd, therefore it's safe to say Y. 1185 1186config X86_MSR 1187 tristate "/dev/cpu/*/msr - Model-specific register support" 1188 ---help--- 1189 This device gives privileged processes access to the x86 1190 Model-Specific Registers (MSRs). It is a character device with 1191 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1192 MSR accesses are directed to a specific CPU on multi-processor 1193 systems. 1194 1195config X86_CPUID 1196 tristate "/dev/cpu/*/cpuid - CPU information support" 1197 ---help--- 1198 This device gives processes access to the x86 CPUID instruction to 1199 be executed on a specific processor. It is a character device 1200 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1201 /dev/cpu/31/cpuid. 1202 1203choice 1204 prompt "High Memory Support" 1205 default HIGHMEM4G 1206 depends on X86_32 1207 1208config NOHIGHMEM 1209 bool "off" 1210 ---help--- 1211 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1212 However, the address space of 32-bit x86 processors is only 4 1213 Gigabytes large. That means that, if you have a large amount of 1214 physical memory, not all of it can be "permanently mapped" by the 1215 kernel. The physical memory that's not permanently mapped is called 1216 "high memory". 1217 1218 If you are compiling a kernel which will never run on a machine with 1219 more than 1 Gigabyte total physical RAM, answer "off" here (default 1220 choice and suitable for most users). This will result in a "3GB/1GB" 1221 split: 3GB are mapped so that each process sees a 3GB virtual memory 1222 space and the remaining part of the 4GB virtual memory space is used 1223 by the kernel to permanently map as much physical memory as 1224 possible. 1225 1226 If the machine has between 1 and 4 Gigabytes physical RAM, then 1227 answer "4GB" here. 1228 1229 If more than 4 Gigabytes is used then answer "64GB" here. This 1230 selection turns Intel PAE (Physical Address Extension) mode on. 1231 PAE implements 3-level paging on IA32 processors. PAE is fully 1232 supported by Linux, PAE mode is implemented on all recent Intel 1233 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1234 then the kernel will not boot on CPUs that don't support PAE! 1235 1236 The actual amount of total physical memory will either be 1237 auto detected or can be forced by using a kernel command line option 1238 such as "mem=256M". (Try "man bootparam" or see the documentation of 1239 your boot loader (lilo or loadlin) about how to pass options to the 1240 kernel at boot time.) 1241 1242 If unsure, say "off". 1243 1244config HIGHMEM4G 1245 bool "4GB" 1246 ---help--- 1247 Select this if you have a 32-bit processor and between 1 and 4 1248 gigabytes of physical RAM. 1249 1250config HIGHMEM64G 1251 bool "64GB" 1252 depends on !M486 1253 select X86_PAE 1254 ---help--- 1255 Select this if you have a 32-bit processor and more than 4 1256 gigabytes of physical RAM. 1257 1258endchoice 1259 1260choice 1261 prompt "Memory split" if EXPERT 1262 default VMSPLIT_3G 1263 depends on X86_32 1264 ---help--- 1265 Select the desired split between kernel and user memory. 1266 1267 If the address range available to the kernel is less than the 1268 physical memory installed, the remaining memory will be available 1269 as "high memory". Accessing high memory is a little more costly 1270 than low memory, as it needs to be mapped into the kernel first. 1271 Note that increasing the kernel address space limits the range 1272 available to user programs, making the address space there 1273 tighter. Selecting anything other than the default 3G/1G split 1274 will also likely make your kernel incompatible with binary-only 1275 kernel modules. 1276 1277 If you are not absolutely sure what you are doing, leave this 1278 option alone! 1279 1280 config VMSPLIT_3G 1281 bool "3G/1G user/kernel split" 1282 config VMSPLIT_3G_OPT 1283 depends on !X86_PAE 1284 bool "3G/1G user/kernel split (for full 1G low memory)" 1285 config VMSPLIT_2G 1286 bool "2G/2G user/kernel split" 1287 config VMSPLIT_2G_OPT 1288 depends on !X86_PAE 1289 bool "2G/2G user/kernel split (for full 2G low memory)" 1290 config VMSPLIT_1G 1291 bool "1G/3G user/kernel split" 1292endchoice 1293 1294config PAGE_OFFSET 1295 hex 1296 default 0xB0000000 if VMSPLIT_3G_OPT 1297 default 0x80000000 if VMSPLIT_2G 1298 default 0x78000000 if VMSPLIT_2G_OPT 1299 default 0x40000000 if VMSPLIT_1G 1300 default 0xC0000000 1301 depends on X86_32 1302 1303config HIGHMEM 1304 def_bool y 1305 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1306 1307config X86_PAE 1308 bool "PAE (Physical Address Extension) Support" 1309 depends on X86_32 && !HIGHMEM4G 1310 ---help--- 1311 PAE is required for NX support, and furthermore enables 1312 larger swapspace support for non-overcommit purposes. It 1313 has the cost of more pagetable lookup overhead, and also 1314 consumes more pagetable space per process. 1315 1316config ARCH_PHYS_ADDR_T_64BIT 1317 def_bool y 1318 depends on X86_64 || X86_PAE 1319 1320config ARCH_DMA_ADDR_T_64BIT 1321 def_bool y 1322 depends on X86_64 || HIGHMEM64G 1323 1324config X86_DIRECT_GBPAGES 1325 def_bool y 1326 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 1327 ---help--- 1328 Certain kernel features effectively disable kernel 1329 linear 1 GB mappings (even if the CPU otherwise 1330 supports them), so don't confuse the user by printing 1331 that we have them enabled. 1332 1333# Common NUMA Features 1334config NUMA 1335 bool "Numa Memory Allocation and Scheduler Support" 1336 depends on SMP 1337 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1338 default y if X86_BIGSMP 1339 ---help--- 1340 Enable NUMA (Non Uniform Memory Access) support. 1341 1342 The kernel will try to allocate memory used by a CPU on the 1343 local memory controller of the CPU and add some more 1344 NUMA awareness to the kernel. 1345 1346 For 64-bit this is recommended if the system is Intel Core i7 1347 (or later), AMD Opteron, or EM64T NUMA. 1348 1349 For 32-bit this is only needed if you boot a 32-bit 1350 kernel on a 64-bit NUMA platform. 1351 1352 Otherwise, you should say N. 1353 1354config AMD_NUMA 1355 def_bool y 1356 prompt "Old style AMD Opteron NUMA detection" 1357 depends on X86_64 && NUMA && PCI 1358 ---help--- 1359 Enable AMD NUMA node topology detection. You should say Y here if 1360 you have a multi processor AMD system. This uses an old method to 1361 read the NUMA configuration directly from the builtin Northbridge 1362 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1363 which also takes priority if both are compiled in. 1364 1365config X86_64_ACPI_NUMA 1366 def_bool y 1367 prompt "ACPI NUMA detection" 1368 depends on X86_64 && NUMA && ACPI && PCI 1369 select ACPI_NUMA 1370 ---help--- 1371 Enable ACPI SRAT based node topology detection. 1372 1373# Some NUMA nodes have memory ranges that span 1374# other nodes. Even though a pfn is valid and 1375# between a node's start and end pfns, it may not 1376# reside on that node. See memmap_init_zone() 1377# for details. 1378config NODES_SPAN_OTHER_NODES 1379 def_bool y 1380 depends on X86_64_ACPI_NUMA 1381 1382config NUMA_EMU 1383 bool "NUMA emulation" 1384 depends on NUMA 1385 ---help--- 1386 Enable NUMA emulation. A flat machine will be split 1387 into virtual nodes when booted with "numa=fake=N", where N is the 1388 number of nodes. This is only useful for debugging. 1389 1390config NODES_SHIFT 1391 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1392 range 1 10 1393 default "10" if MAXSMP 1394 default "6" if X86_64 1395 default "3" 1396 depends on NEED_MULTIPLE_NODES 1397 ---help--- 1398 Specify the maximum number of NUMA Nodes available on the target 1399 system. Increases memory reserved to accommodate various tables. 1400 1401config ARCH_HAVE_MEMORY_PRESENT 1402 def_bool y 1403 depends on X86_32 && DISCONTIGMEM 1404 1405config NEED_NODE_MEMMAP_SIZE 1406 def_bool y 1407 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1408 1409config ARCH_FLATMEM_ENABLE 1410 def_bool y 1411 depends on X86_32 && !NUMA 1412 1413config ARCH_DISCONTIGMEM_ENABLE 1414 def_bool y 1415 depends on NUMA && X86_32 1416 1417config ARCH_DISCONTIGMEM_DEFAULT 1418 def_bool y 1419 depends on NUMA && X86_32 1420 1421config ARCH_SPARSEMEM_ENABLE 1422 def_bool y 1423 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1424 select SPARSEMEM_STATIC if X86_32 1425 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1426 1427config ARCH_SPARSEMEM_DEFAULT 1428 def_bool y 1429 depends on X86_64 1430 1431config ARCH_SELECT_MEMORY_MODEL 1432 def_bool y 1433 depends on ARCH_SPARSEMEM_ENABLE 1434 1435config ARCH_MEMORY_PROBE 1436 bool "Enable sysfs memory/probe interface" 1437 depends on X86_64 && MEMORY_HOTPLUG 1438 help 1439 This option enables a sysfs memory/probe interface for testing. 1440 See Documentation/memory-hotplug.txt for more information. 1441 If you are unsure how to answer this question, answer N. 1442 1443config ARCH_PROC_KCORE_TEXT 1444 def_bool y 1445 depends on X86_64 && PROC_KCORE 1446 1447config ILLEGAL_POINTER_VALUE 1448 hex 1449 default 0 if X86_32 1450 default 0xdead000000000000 if X86_64 1451 1452source "mm/Kconfig" 1453 1454config X86_PMEM_LEGACY_DEVICE 1455 bool 1456 1457config X86_PMEM_LEGACY 1458 tristate "Support non-standard NVDIMMs and ADR protected memory" 1459 depends on PHYS_ADDR_T_64BIT 1460 depends on BLK_DEV 1461 select X86_PMEM_LEGACY_DEVICE 1462 select LIBNVDIMM 1463 help 1464 Treat memory marked using the non-standard e820 type of 12 as used 1465 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1466 The kernel will offer these regions to the 'pmem' driver so 1467 they can be used for persistent storage. 1468 1469 Say Y if unsure. 1470 1471config HIGHPTE 1472 bool "Allocate 3rd-level pagetables from highmem" 1473 depends on HIGHMEM 1474 ---help--- 1475 The VM uses one page table entry for each page of physical memory. 1476 For systems with a lot of RAM, this can be wasteful of precious 1477 low memory. Setting this option will put user-space page table 1478 entries in high memory. 1479 1480config X86_CHECK_BIOS_CORRUPTION 1481 bool "Check for low memory corruption" 1482 ---help--- 1483 Periodically check for memory corruption in low memory, which 1484 is suspected to be caused by BIOS. Even when enabled in the 1485 configuration, it is disabled at runtime. Enable it by 1486 setting "memory_corruption_check=1" on the kernel command 1487 line. By default it scans the low 64k of memory every 60 1488 seconds; see the memory_corruption_check_size and 1489 memory_corruption_check_period parameters in 1490 Documentation/kernel-parameters.txt to adjust this. 1491 1492 When enabled with the default parameters, this option has 1493 almost no overhead, as it reserves a relatively small amount 1494 of memory and scans it infrequently. It both detects corruption 1495 and prevents it from affecting the running system. 1496 1497 It is, however, intended as a diagnostic tool; if repeatable 1498 BIOS-originated corruption always affects the same memory, 1499 you can use memmap= to prevent the kernel from using that 1500 memory. 1501 1502config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1503 bool "Set the default setting of memory_corruption_check" 1504 depends on X86_CHECK_BIOS_CORRUPTION 1505 default y 1506 ---help--- 1507 Set whether the default state of memory_corruption_check is 1508 on or off. 1509 1510config X86_RESERVE_LOW 1511 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1512 default 64 1513 range 4 640 1514 ---help--- 1515 Specify the amount of low memory to reserve for the BIOS. 1516 1517 The first page contains BIOS data structures that the kernel 1518 must not use, so that page must always be reserved. 1519 1520 By default we reserve the first 64K of physical RAM, as a 1521 number of BIOSes are known to corrupt that memory range 1522 during events such as suspend/resume or monitor cable 1523 insertion, so it must not be used by the kernel. 1524 1525 You can set this to 4 if you are absolutely sure that you 1526 trust the BIOS to get all its memory reservations and usages 1527 right. If you know your BIOS have problems beyond the 1528 default 64K area, you can set this to 640 to avoid using the 1529 entire low memory range. 1530 1531 If you have doubts about the BIOS (e.g. suspend/resume does 1532 not work or there's kernel crashes after certain hardware 1533 hotplug events) then you might want to enable 1534 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1535 typical corruption patterns. 1536 1537 Leave this to the default value of 64 if you are unsure. 1538 1539config MATH_EMULATION 1540 bool 1541 depends on MODIFY_LDT_SYSCALL 1542 prompt "Math emulation" if X86_32 1543 ---help--- 1544 Linux can emulate a math coprocessor (used for floating point 1545 operations) if you don't have one. 486DX and Pentium processors have 1546 a math coprocessor built in, 486SX and 386 do not, unless you added 1547 a 487DX or 387, respectively. (The messages during boot time can 1548 give you some hints here ["man dmesg"].) Everyone needs either a 1549 coprocessor or this emulation. 1550 1551 If you don't have a math coprocessor, you need to say Y here; if you 1552 say Y here even though you have a coprocessor, the coprocessor will 1553 be used nevertheless. (This behavior can be changed with the kernel 1554 command line option "no387", which comes handy if your coprocessor 1555 is broken. Try "man bootparam" or see the documentation of your boot 1556 loader (lilo or loadlin) about how to pass options to the kernel at 1557 boot time.) This means that it is a good idea to say Y here if you 1558 intend to use this kernel on different machines. 1559 1560 More information about the internals of the Linux math coprocessor 1561 emulation can be found in <file:arch/x86/math-emu/README>. 1562 1563 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1564 kernel, it won't hurt. 1565 1566config MTRR 1567 def_bool y 1568 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1569 ---help--- 1570 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1571 the Memory Type Range Registers (MTRRs) may be used to control 1572 processor access to memory ranges. This is most useful if you have 1573 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1574 allows bus write transfers to be combined into a larger transfer 1575 before bursting over the PCI/AGP bus. This can increase performance 1576 of image write operations 2.5 times or more. Saying Y here creates a 1577 /proc/mtrr file which may be used to manipulate your processor's 1578 MTRRs. Typically the X server should use this. 1579 1580 This code has a reasonably generic interface so that similar 1581 control registers on other processors can be easily supported 1582 as well: 1583 1584 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1585 Registers (ARRs) which provide a similar functionality to MTRRs. For 1586 these, the ARRs are used to emulate the MTRRs. 1587 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1588 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1589 write-combining. All of these processors are supported by this code 1590 and it makes sense to say Y here if you have one of them. 1591 1592 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1593 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1594 can lead to all sorts of problems, so it's good to say Y here. 1595 1596 You can safely say Y even if your machine doesn't have MTRRs, you'll 1597 just add about 9 KB to your kernel. 1598 1599 See <file:Documentation/x86/mtrr.txt> for more information. 1600 1601config MTRR_SANITIZER 1602 def_bool y 1603 prompt "MTRR cleanup support" 1604 depends on MTRR 1605 ---help--- 1606 Convert MTRR layout from continuous to discrete, so X drivers can 1607 add writeback entries. 1608 1609 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1610 The largest mtrr entry size for a continuous block can be set with 1611 mtrr_chunk_size. 1612 1613 If unsure, say Y. 1614 1615config MTRR_SANITIZER_ENABLE_DEFAULT 1616 int "MTRR cleanup enable value (0-1)" 1617 range 0 1 1618 default "0" 1619 depends on MTRR_SANITIZER 1620 ---help--- 1621 Enable mtrr cleanup default value 1622 1623config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1624 int "MTRR cleanup spare reg num (0-7)" 1625 range 0 7 1626 default "1" 1627 depends on MTRR_SANITIZER 1628 ---help--- 1629 mtrr cleanup spare entries default, it can be changed via 1630 mtrr_spare_reg_nr=N on the kernel command line. 1631 1632config X86_PAT 1633 def_bool y 1634 prompt "x86 PAT support" if EXPERT 1635 depends on MTRR 1636 ---help--- 1637 Use PAT attributes to setup page level cache control. 1638 1639 PATs are the modern equivalents of MTRRs and are much more 1640 flexible than MTRRs. 1641 1642 Say N here if you see bootup problems (boot crash, boot hang, 1643 spontaneous reboots) or a non-working video driver. 1644 1645 If unsure, say Y. 1646 1647config ARCH_USES_PG_UNCACHED 1648 def_bool y 1649 depends on X86_PAT 1650 1651config ARCH_RANDOM 1652 def_bool y 1653 prompt "x86 architectural random number generator" if EXPERT 1654 ---help--- 1655 Enable the x86 architectural RDRAND instruction 1656 (Intel Bull Mountain technology) to generate random numbers. 1657 If supported, this is a high bandwidth, cryptographically 1658 secure hardware random number generator. 1659 1660config X86_SMAP 1661 def_bool y 1662 prompt "Supervisor Mode Access Prevention" if EXPERT 1663 ---help--- 1664 Supervisor Mode Access Prevention (SMAP) is a security 1665 feature in newer Intel processors. There is a small 1666 performance cost if this enabled and turned on; there is 1667 also a small increase in the kernel size if this is enabled. 1668 1669 If unsure, say Y. 1670 1671config X86_INTEL_MPX 1672 prompt "Intel MPX (Memory Protection Extensions)" 1673 def_bool n 1674 depends on CPU_SUP_INTEL 1675 ---help--- 1676 MPX provides hardware features that can be used in 1677 conjunction with compiler-instrumented code to check 1678 memory references. It is designed to detect buffer 1679 overflow or underflow bugs. 1680 1681 This option enables running applications which are 1682 instrumented or otherwise use MPX. It does not use MPX 1683 itself inside the kernel or to protect the kernel 1684 against bad memory references. 1685 1686 Enabling this option will make the kernel larger: 1687 ~8k of kernel text and 36 bytes of data on a 64-bit 1688 defconfig. It adds a long to the 'mm_struct' which 1689 will increase the kernel memory overhead of each 1690 process and adds some branches to paths used during 1691 exec() and munmap(). 1692 1693 For details, see Documentation/x86/intel_mpx.txt 1694 1695 If unsure, say N. 1696 1697config EFI 1698 bool "EFI runtime service support" 1699 depends on ACPI 1700 select UCS2_STRING 1701 select EFI_RUNTIME_WRAPPERS 1702 ---help--- 1703 This enables the kernel to use EFI runtime services that are 1704 available (such as the EFI variable services). 1705 1706 This option is only useful on systems that have EFI firmware. 1707 In addition, you should use the latest ELILO loader available 1708 at <http://elilo.sourceforge.net> in order to take advantage 1709 of EFI runtime services. However, even with this option, the 1710 resultant kernel should continue to boot on existing non-EFI 1711 platforms. 1712 1713config EFI_STUB 1714 bool "EFI stub support" 1715 depends on EFI && !X86_USE_3DNOW 1716 select RELOCATABLE 1717 ---help--- 1718 This kernel feature allows a bzImage to be loaded directly 1719 by EFI firmware without the use of a bootloader. 1720 1721 See Documentation/efi-stub.txt for more information. 1722 1723config EFI_MIXED 1724 bool "EFI mixed-mode support" 1725 depends on EFI_STUB && X86_64 1726 ---help--- 1727 Enabling this feature allows a 64-bit kernel to be booted 1728 on a 32-bit firmware, provided that your CPU supports 64-bit 1729 mode. 1730 1731 Note that it is not possible to boot a mixed-mode enabled 1732 kernel via the EFI boot stub - a bootloader that supports 1733 the EFI handover protocol must be used. 1734 1735 If unsure, say N. 1736 1737config SECCOMP 1738 def_bool y 1739 prompt "Enable seccomp to safely compute untrusted bytecode" 1740 ---help--- 1741 This kernel feature is useful for number crunching applications 1742 that may need to compute untrusted bytecode during their 1743 execution. By using pipes or other transports made available to 1744 the process as file descriptors supporting the read/write 1745 syscalls, it's possible to isolate those applications in 1746 their own address space using seccomp. Once seccomp is 1747 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1748 and the task is only allowed to execute a few safe syscalls 1749 defined by each seccomp mode. 1750 1751 If unsure, say Y. Only embedded should say N here. 1752 1753source kernel/Kconfig.hz 1754 1755config KEXEC 1756 bool "kexec system call" 1757 select KEXEC_CORE 1758 ---help--- 1759 kexec is a system call that implements the ability to shutdown your 1760 current kernel, and to start another kernel. It is like a reboot 1761 but it is independent of the system firmware. And like a reboot 1762 you can start any kernel with it, not just Linux. 1763 1764 The name comes from the similarity to the exec system call. 1765 1766 It is an ongoing process to be certain the hardware in a machine 1767 is properly shutdown, so do not be surprised if this code does not 1768 initially work for you. As of this writing the exact hardware 1769 interface is strongly in flux, so no good recommendation can be 1770 made. 1771 1772config KEXEC_FILE 1773 bool "kexec file based system call" 1774 select KEXEC_CORE 1775 select BUILD_BIN2C 1776 depends on X86_64 1777 depends on CRYPTO=y 1778 depends on CRYPTO_SHA256=y 1779 ---help--- 1780 This is new version of kexec system call. This system call is 1781 file based and takes file descriptors as system call argument 1782 for kernel and initramfs as opposed to list of segments as 1783 accepted by previous system call. 1784 1785config KEXEC_VERIFY_SIG 1786 bool "Verify kernel signature during kexec_file_load() syscall" 1787 depends on KEXEC_FILE 1788 ---help--- 1789 This option makes kernel signature verification mandatory for 1790 the kexec_file_load() syscall. 1791 1792 In addition to that option, you need to enable signature 1793 verification for the corresponding kernel image type being 1794 loaded in order for this to work. 1795 1796config KEXEC_BZIMAGE_VERIFY_SIG 1797 bool "Enable bzImage signature verification support" 1798 depends on KEXEC_VERIFY_SIG 1799 depends on SIGNED_PE_FILE_VERIFICATION 1800 select SYSTEM_TRUSTED_KEYRING 1801 ---help--- 1802 Enable bzImage signature verification support. 1803 1804config CRASH_DUMP 1805 bool "kernel crash dumps" 1806 depends on X86_64 || (X86_32 && HIGHMEM) 1807 ---help--- 1808 Generate crash dump after being started by kexec. 1809 This should be normally only set in special crash dump kernels 1810 which are loaded in the main kernel with kexec-tools into 1811 a specially reserved region and then later executed after 1812 a crash by kdump/kexec. The crash dump kernel must be compiled 1813 to a memory address not used by the main kernel or BIOS using 1814 PHYSICAL_START, or it must be built as a relocatable image 1815 (CONFIG_RELOCATABLE=y). 1816 For more details see Documentation/kdump/kdump.txt 1817 1818config KEXEC_JUMP 1819 bool "kexec jump" 1820 depends on KEXEC && HIBERNATION 1821 ---help--- 1822 Jump between original kernel and kexeced kernel and invoke 1823 code in physical address mode via KEXEC 1824 1825config PHYSICAL_START 1826 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1827 default "0x1000000" 1828 ---help--- 1829 This gives the physical address where the kernel is loaded. 1830 1831 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1832 bzImage will decompress itself to above physical address and 1833 run from there. Otherwise, bzImage will run from the address where 1834 it has been loaded by the boot loader and will ignore above physical 1835 address. 1836 1837 In normal kdump cases one does not have to set/change this option 1838 as now bzImage can be compiled as a completely relocatable image 1839 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1840 address. This option is mainly useful for the folks who don't want 1841 to use a bzImage for capturing the crash dump and want to use a 1842 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1843 to be specifically compiled to run from a specific memory area 1844 (normally a reserved region) and this option comes handy. 1845 1846 So if you are using bzImage for capturing the crash dump, 1847 leave the value here unchanged to 0x1000000 and set 1848 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1849 for capturing the crash dump change this value to start of 1850 the reserved region. In other words, it can be set based on 1851 the "X" value as specified in the "crashkernel=YM@XM" 1852 command line boot parameter passed to the panic-ed 1853 kernel. Please take a look at Documentation/kdump/kdump.txt 1854 for more details about crash dumps. 1855 1856 Usage of bzImage for capturing the crash dump is recommended as 1857 one does not have to build two kernels. Same kernel can be used 1858 as production kernel and capture kernel. Above option should have 1859 gone away after relocatable bzImage support is introduced. But it 1860 is present because there are users out there who continue to use 1861 vmlinux for dump capture. This option should go away down the 1862 line. 1863 1864 Don't change this unless you know what you are doing. 1865 1866config RELOCATABLE 1867 bool "Build a relocatable kernel" 1868 default y 1869 ---help--- 1870 This builds a kernel image that retains relocation information 1871 so it can be loaded someplace besides the default 1MB. 1872 The relocations tend to make the kernel binary about 10% larger, 1873 but are discarded at runtime. 1874 1875 One use is for the kexec on panic case where the recovery kernel 1876 must live at a different physical address than the primary 1877 kernel. 1878 1879 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1880 it has been loaded at and the compile time physical address 1881 (CONFIG_PHYSICAL_START) is used as the minimum location. 1882 1883config RANDOMIZE_BASE 1884 bool "Randomize the address of the kernel image" 1885 depends on RELOCATABLE 1886 default n 1887 ---help--- 1888 Randomizes the physical and virtual address at which the 1889 kernel image is decompressed, as a security feature that 1890 deters exploit attempts relying on knowledge of the location 1891 of kernel internals. 1892 1893 Entropy is generated using the RDRAND instruction if it is 1894 supported. If RDTSC is supported, it is used as well. If 1895 neither RDRAND nor RDTSC are supported, then randomness is 1896 read from the i8254 timer. 1897 1898 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1899 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1900 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1901 minimum of 2MiB, only 10 bits of entropy is theoretically 1902 possible. At best, due to page table layouts, 64-bit can use 1903 9 bits of entropy and 32-bit uses 8 bits. 1904 1905 If unsure, say N. 1906 1907config RANDOMIZE_BASE_MAX_OFFSET 1908 hex "Maximum kASLR offset allowed" if EXPERT 1909 depends on RANDOMIZE_BASE 1910 range 0x0 0x20000000 if X86_32 1911 default "0x20000000" if X86_32 1912 range 0x0 0x40000000 if X86_64 1913 default "0x40000000" if X86_64 1914 ---help--- 1915 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1916 memory is used to determine the maximal offset in bytes that will 1917 be applied to the kernel when kernel Address Space Layout 1918 Randomization (kASLR) is active. This must be a multiple of 1919 PHYSICAL_ALIGN. 1920 1921 On 32-bit this is limited to 512MiB by page table layouts. The 1922 default is 512MiB. 1923 1924 On 64-bit this is limited by how the kernel fixmap page table is 1925 positioned, so this cannot be larger than 1GiB currently. Without 1926 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1927 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1928 modules area will shrink to compensate, up to the current maximum 1929 1GiB to 1GiB split. The default is 1GiB. 1930 1931 If unsure, leave at the default value. 1932 1933# Relocation on x86 needs some additional build support 1934config X86_NEED_RELOCS 1935 def_bool y 1936 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1937 1938config PHYSICAL_ALIGN 1939 hex "Alignment value to which kernel should be aligned" 1940 default "0x200000" 1941 range 0x2000 0x1000000 if X86_32 1942 range 0x200000 0x1000000 if X86_64 1943 ---help--- 1944 This value puts the alignment restrictions on physical address 1945 where kernel is loaded and run from. Kernel is compiled for an 1946 address which meets above alignment restriction. 1947 1948 If bootloader loads the kernel at a non-aligned address and 1949 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1950 address aligned to above value and run from there. 1951 1952 If bootloader loads the kernel at a non-aligned address and 1953 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1954 load address and decompress itself to the address it has been 1955 compiled for and run from there. The address for which kernel is 1956 compiled already meets above alignment restrictions. Hence the 1957 end result is that kernel runs from a physical address meeting 1958 above alignment restrictions. 1959 1960 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1961 this value must be a multiple of 0x200000. 1962 1963 Don't change this unless you know what you are doing. 1964 1965config HOTPLUG_CPU 1966 bool "Support for hot-pluggable CPUs" 1967 depends on SMP 1968 ---help--- 1969 Say Y here to allow turning CPUs off and on. CPUs can be 1970 controlled through /sys/devices/system/cpu. 1971 ( Note: power management support will enable this option 1972 automatically on SMP systems. ) 1973 Say N if you want to disable CPU hotplug. 1974 1975config BOOTPARAM_HOTPLUG_CPU0 1976 bool "Set default setting of cpu0_hotpluggable" 1977 default n 1978 depends on HOTPLUG_CPU 1979 ---help--- 1980 Set whether default state of cpu0_hotpluggable is on or off. 1981 1982 Say Y here to enable CPU0 hotplug by default. If this switch 1983 is turned on, there is no need to give cpu0_hotplug kernel 1984 parameter and the CPU0 hotplug feature is enabled by default. 1985 1986 Please note: there are two known CPU0 dependencies if you want 1987 to enable the CPU0 hotplug feature either by this switch or by 1988 cpu0_hotplug kernel parameter. 1989 1990 First, resume from hibernate or suspend always starts from CPU0. 1991 So hibernate and suspend are prevented if CPU0 is offline. 1992 1993 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1994 offline if any interrupt can not migrate out of CPU0. There may 1995 be other CPU0 dependencies. 1996 1997 Please make sure the dependencies are under your control before 1998 you enable this feature. 1999 2000 Say N if you don't want to enable CPU0 hotplug feature by default. 2001 You still can enable the CPU0 hotplug feature at boot by kernel 2002 parameter cpu0_hotplug. 2003 2004config DEBUG_HOTPLUG_CPU0 2005 def_bool n 2006 prompt "Debug CPU0 hotplug" 2007 depends on HOTPLUG_CPU 2008 ---help--- 2009 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2010 soon as possible and boots up userspace with CPU0 offlined. User 2011 can online CPU0 back after boot time. 2012 2013 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2014 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2015 compilation or giving cpu0_hotplug kernel parameter at boot. 2016 2017 If unsure, say N. 2018 2019config COMPAT_VDSO 2020 def_bool n 2021 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2022 depends on X86_32 || IA32_EMULATION 2023 ---help--- 2024 Certain buggy versions of glibc will crash if they are 2025 presented with a 32-bit vDSO that is not mapped at the address 2026 indicated in its segment table. 2027 2028 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2029 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2030 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2031 the only released version with the bug, but OpenSUSE 9 2032 contains a buggy "glibc 2.3.2". 2033 2034 The symptom of the bug is that everything crashes on startup, saying: 2035 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2036 2037 Saying Y here changes the default value of the vdso32 boot 2038 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2039 This works around the glibc bug but hurts performance. 2040 2041 If unsure, say N: if you are compiling your own kernel, you 2042 are unlikely to be using a buggy version of glibc. 2043 2044config CMDLINE_BOOL 2045 bool "Built-in kernel command line" 2046 ---help--- 2047 Allow for specifying boot arguments to the kernel at 2048 build time. On some systems (e.g. embedded ones), it is 2049 necessary or convenient to provide some or all of the 2050 kernel boot arguments with the kernel itself (that is, 2051 to not rely on the boot loader to provide them.) 2052 2053 To compile command line arguments into the kernel, 2054 set this option to 'Y', then fill in the 2055 boot arguments in CONFIG_CMDLINE. 2056 2057 Systems with fully functional boot loaders (i.e. non-embedded) 2058 should leave this option set to 'N'. 2059 2060config CMDLINE 2061 string "Built-in kernel command string" 2062 depends on CMDLINE_BOOL 2063 default "" 2064 ---help--- 2065 Enter arguments here that should be compiled into the kernel 2066 image and used at boot time. If the boot loader provides a 2067 command line at boot time, it is appended to this string to 2068 form the full kernel command line, when the system boots. 2069 2070 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2071 change this behavior. 2072 2073 In most cases, the command line (whether built-in or provided 2074 by the boot loader) should specify the device for the root 2075 file system. 2076 2077config CMDLINE_OVERRIDE 2078 bool "Built-in command line overrides boot loader arguments" 2079 depends on CMDLINE_BOOL 2080 ---help--- 2081 Set this option to 'Y' to have the kernel ignore the boot loader 2082 command line, and use ONLY the built-in command line. 2083 2084 This is used to work around broken boot loaders. This should 2085 be set to 'N' under normal conditions. 2086 2087config MODIFY_LDT_SYSCALL 2088 bool "Enable the LDT (local descriptor table)" if EXPERT 2089 default y 2090 ---help--- 2091 Linux can allow user programs to install a per-process x86 2092 Local Descriptor Table (LDT) using the modify_ldt(2) system 2093 call. This is required to run 16-bit or segmented code such as 2094 DOSEMU or some Wine programs. It is also used by some very old 2095 threading libraries. 2096 2097 Enabling this feature adds a small amount of overhead to 2098 context switches and increases the low-level kernel attack 2099 surface. Disabling it removes the modify_ldt(2) system call. 2100 2101 Saying 'N' here may make sense for embedded or server kernels. 2102 2103source "kernel/livepatch/Kconfig" 2104 2105endmenu 2106 2107config ARCH_ENABLE_MEMORY_HOTPLUG 2108 def_bool y 2109 depends on X86_64 || (X86_32 && HIGHMEM) 2110 2111config ARCH_ENABLE_MEMORY_HOTREMOVE 2112 def_bool y 2113 depends on MEMORY_HOTPLUG 2114 2115config USE_PERCPU_NUMA_NODE_ID 2116 def_bool y 2117 depends on NUMA 2118 2119config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2120 def_bool y 2121 depends on X86_64 || X86_PAE 2122 2123config ARCH_ENABLE_HUGEPAGE_MIGRATION 2124 def_bool y 2125 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2126 2127menu "Power management and ACPI options" 2128 2129config ARCH_HIBERNATION_HEADER 2130 def_bool y 2131 depends on X86_64 && HIBERNATION 2132 2133source "kernel/power/Kconfig" 2134 2135source "drivers/acpi/Kconfig" 2136 2137source "drivers/sfi/Kconfig" 2138 2139config X86_APM_BOOT 2140 def_bool y 2141 depends on APM 2142 2143menuconfig APM 2144 tristate "APM (Advanced Power Management) BIOS support" 2145 depends on X86_32 && PM_SLEEP 2146 ---help--- 2147 APM is a BIOS specification for saving power using several different 2148 techniques. This is mostly useful for battery powered laptops with 2149 APM compliant BIOSes. If you say Y here, the system time will be 2150 reset after a RESUME operation, the /proc/apm device will provide 2151 battery status information, and user-space programs will receive 2152 notification of APM "events" (e.g. battery status change). 2153 2154 If you select "Y" here, you can disable actual use of the APM 2155 BIOS by passing the "apm=off" option to the kernel at boot time. 2156 2157 Note that the APM support is almost completely disabled for 2158 machines with more than one CPU. 2159 2160 In order to use APM, you will need supporting software. For location 2161 and more information, read <file:Documentation/power/apm-acpi.txt> 2162 and the Battery Powered Linux mini-HOWTO, available from 2163 <http://www.tldp.org/docs.html#howto>. 2164 2165 This driver does not spin down disk drives (see the hdparm(8) 2166 manpage ("man 8 hdparm") for that), and it doesn't turn off 2167 VESA-compliant "green" monitors. 2168 2169 This driver does not support the TI 4000M TravelMate and the ACER 2170 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2171 desktop machines also don't have compliant BIOSes, and this driver 2172 may cause those machines to panic during the boot phase. 2173 2174 Generally, if you don't have a battery in your machine, there isn't 2175 much point in using this driver and you should say N. If you get 2176 random kernel OOPSes or reboots that don't seem to be related to 2177 anything, try disabling/enabling this option (or disabling/enabling 2178 APM in your BIOS). 2179 2180 Some other things you should try when experiencing seemingly random, 2181 "weird" problems: 2182 2183 1) make sure that you have enough swap space and that it is 2184 enabled. 2185 2) pass the "no-hlt" option to the kernel 2186 3) switch on floating point emulation in the kernel and pass 2187 the "no387" option to the kernel 2188 4) pass the "floppy=nodma" option to the kernel 2189 5) pass the "mem=4M" option to the kernel (thereby disabling 2190 all but the first 4 MB of RAM) 2191 6) make sure that the CPU is not over clocked. 2192 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2193 8) disable the cache from your BIOS settings 2194 9) install a fan for the video card or exchange video RAM 2195 10) install a better fan for the CPU 2196 11) exchange RAM chips 2197 12) exchange the motherboard. 2198 2199 To compile this driver as a module, choose M here: the 2200 module will be called apm. 2201 2202if APM 2203 2204config APM_IGNORE_USER_SUSPEND 2205 bool "Ignore USER SUSPEND" 2206 ---help--- 2207 This option will ignore USER SUSPEND requests. On machines with a 2208 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2209 series notebooks, it is necessary to say Y because of a BIOS bug. 2210 2211config APM_DO_ENABLE 2212 bool "Enable PM at boot time" 2213 ---help--- 2214 Enable APM features at boot time. From page 36 of the APM BIOS 2215 specification: "When disabled, the APM BIOS does not automatically 2216 power manage devices, enter the Standby State, enter the Suspend 2217 State, or take power saving steps in response to CPU Idle calls." 2218 This driver will make CPU Idle calls when Linux is idle (unless this 2219 feature is turned off -- see "Do CPU IDLE calls", below). This 2220 should always save battery power, but more complicated APM features 2221 will be dependent on your BIOS implementation. You may need to turn 2222 this option off if your computer hangs at boot time when using APM 2223 support, or if it beeps continuously instead of suspending. Turn 2224 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2225 T400CDT. This is off by default since most machines do fine without 2226 this feature. 2227 2228config APM_CPU_IDLE 2229 depends on CPU_IDLE 2230 bool "Make CPU Idle calls when idle" 2231 ---help--- 2232 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2233 On some machines, this can activate improved power savings, such as 2234 a slowed CPU clock rate, when the machine is idle. These idle calls 2235 are made after the idle loop has run for some length of time (e.g., 2236 333 mS). On some machines, this will cause a hang at boot time or 2237 whenever the CPU becomes idle. (On machines with more than one CPU, 2238 this option does nothing.) 2239 2240config APM_DISPLAY_BLANK 2241 bool "Enable console blanking using APM" 2242 ---help--- 2243 Enable console blanking using the APM. Some laptops can use this to 2244 turn off the LCD backlight when the screen blanker of the Linux 2245 virtual console blanks the screen. Note that this is only used by 2246 the virtual console screen blanker, and won't turn off the backlight 2247 when using the X Window system. This also doesn't have anything to 2248 do with your VESA-compliant power-saving monitor. Further, this 2249 option doesn't work for all laptops -- it might not turn off your 2250 backlight at all, or it might print a lot of errors to the console, 2251 especially if you are using gpm. 2252 2253config APM_ALLOW_INTS 2254 bool "Allow interrupts during APM BIOS calls" 2255 ---help--- 2256 Normally we disable external interrupts while we are making calls to 2257 the APM BIOS as a measure to lessen the effects of a badly behaving 2258 BIOS implementation. The BIOS should reenable interrupts if it 2259 needs to. Unfortunately, some BIOSes do not -- especially those in 2260 many of the newer IBM Thinkpads. If you experience hangs when you 2261 suspend, try setting this to Y. Otherwise, say N. 2262 2263endif # APM 2264 2265source "drivers/cpufreq/Kconfig" 2266 2267source "drivers/cpuidle/Kconfig" 2268 2269source "drivers/idle/Kconfig" 2270 2271endmenu 2272 2273 2274menu "Bus options (PCI etc.)" 2275 2276config PCI 2277 bool "PCI support" 2278 default y 2279 ---help--- 2280 Find out whether you have a PCI motherboard. PCI is the name of a 2281 bus system, i.e. the way the CPU talks to the other stuff inside 2282 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2283 VESA. If you have PCI, say Y, otherwise N. 2284 2285choice 2286 prompt "PCI access mode" 2287 depends on X86_32 && PCI 2288 default PCI_GOANY 2289 ---help--- 2290 On PCI systems, the BIOS can be used to detect the PCI devices and 2291 determine their configuration. However, some old PCI motherboards 2292 have BIOS bugs and may crash if this is done. Also, some embedded 2293 PCI-based systems don't have any BIOS at all. Linux can also try to 2294 detect the PCI hardware directly without using the BIOS. 2295 2296 With this option, you can specify how Linux should detect the 2297 PCI devices. If you choose "BIOS", the BIOS will be used, 2298 if you choose "Direct", the BIOS won't be used, and if you 2299 choose "MMConfig", then PCI Express MMCONFIG will be used. 2300 If you choose "Any", the kernel will try MMCONFIG, then the 2301 direct access method and falls back to the BIOS if that doesn't 2302 work. If unsure, go with the default, which is "Any". 2303 2304config PCI_GOBIOS 2305 bool "BIOS" 2306 2307config PCI_GOMMCONFIG 2308 bool "MMConfig" 2309 2310config PCI_GODIRECT 2311 bool "Direct" 2312 2313config PCI_GOOLPC 2314 bool "OLPC XO-1" 2315 depends on OLPC 2316 2317config PCI_GOANY 2318 bool "Any" 2319 2320endchoice 2321 2322config PCI_BIOS 2323 def_bool y 2324 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2325 2326# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2327config PCI_DIRECT 2328 def_bool y 2329 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2330 2331config PCI_MMCONFIG 2332 def_bool y 2333 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2334 2335config PCI_OLPC 2336 def_bool y 2337 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2338 2339config PCI_XEN 2340 def_bool y 2341 depends on PCI && XEN 2342 select SWIOTLB_XEN 2343 2344config PCI_DOMAINS 2345 def_bool y 2346 depends on PCI 2347 2348config PCI_MMCONFIG 2349 bool "Support mmconfig PCI config space access" 2350 depends on X86_64 && PCI && ACPI 2351 2352config PCI_CNB20LE_QUIRK 2353 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2354 depends on PCI 2355 help 2356 Read the PCI windows out of the CNB20LE host bridge. This allows 2357 PCI hotplug to work on systems with the CNB20LE chipset which do 2358 not have ACPI. 2359 2360 There's no public spec for this chipset, and this functionality 2361 is known to be incomplete. 2362 2363 You should say N unless you know you need this. 2364 2365source "drivers/pci/pcie/Kconfig" 2366 2367source "drivers/pci/Kconfig" 2368 2369# x86_64 have no ISA slots, but can have ISA-style DMA. 2370config ISA_DMA_API 2371 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2372 default y 2373 help 2374 Enables ISA-style DMA support for devices requiring such controllers. 2375 If unsure, say Y. 2376 2377if X86_32 2378 2379config ISA 2380 bool "ISA support" 2381 ---help--- 2382 Find out whether you have ISA slots on your motherboard. ISA is the 2383 name of a bus system, i.e. the way the CPU talks to the other stuff 2384 inside your box. Other bus systems are PCI, EISA, MicroChannel 2385 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2386 newer boards don't support it. If you have ISA, say Y, otherwise N. 2387 2388config EISA 2389 bool "EISA support" 2390 depends on ISA 2391 ---help--- 2392 The Extended Industry Standard Architecture (EISA) bus was 2393 developed as an open alternative to the IBM MicroChannel bus. 2394 2395 The EISA bus provided some of the features of the IBM MicroChannel 2396 bus while maintaining backward compatibility with cards made for 2397 the older ISA bus. The EISA bus saw limited use between 1988 and 2398 1995 when it was made obsolete by the PCI bus. 2399 2400 Say Y here if you are building a kernel for an EISA-based machine. 2401 2402 Otherwise, say N. 2403 2404source "drivers/eisa/Kconfig" 2405 2406config SCx200 2407 tristate "NatSemi SCx200 support" 2408 ---help--- 2409 This provides basic support for National Semiconductor's 2410 (now AMD's) Geode processors. The driver probes for the 2411 PCI-IDs of several on-chip devices, so its a good dependency 2412 for other scx200_* drivers. 2413 2414 If compiled as a module, the driver is named scx200. 2415 2416config SCx200HR_TIMER 2417 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2418 depends on SCx200 2419 default y 2420 ---help--- 2421 This driver provides a clocksource built upon the on-chip 2422 27MHz high-resolution timer. Its also a workaround for 2423 NSC Geode SC-1100's buggy TSC, which loses time when the 2424 processor goes idle (as is done by the scheduler). The 2425 other workaround is idle=poll boot option. 2426 2427config OLPC 2428 bool "One Laptop Per Child support" 2429 depends on !X86_PAE 2430 select GPIOLIB 2431 select OF 2432 select OF_PROMTREE 2433 select IRQ_DOMAIN 2434 ---help--- 2435 Add support for detecting the unique features of the OLPC 2436 XO hardware. 2437 2438config OLPC_XO1_PM 2439 bool "OLPC XO-1 Power Management" 2440 depends on OLPC && MFD_CS5535 && PM_SLEEP 2441 select MFD_CORE 2442 ---help--- 2443 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2444 2445config OLPC_XO1_RTC 2446 bool "OLPC XO-1 Real Time Clock" 2447 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2448 ---help--- 2449 Add support for the XO-1 real time clock, which can be used as a 2450 programmable wakeup source. 2451 2452config OLPC_XO1_SCI 2453 bool "OLPC XO-1 SCI extras" 2454 depends on OLPC && OLPC_XO1_PM 2455 depends on INPUT=y 2456 select POWER_SUPPLY 2457 select GPIO_CS5535 2458 select MFD_CORE 2459 ---help--- 2460 Add support for SCI-based features of the OLPC XO-1 laptop: 2461 - EC-driven system wakeups 2462 - Power button 2463 - Ebook switch 2464 - Lid switch 2465 - AC adapter status updates 2466 - Battery status updates 2467 2468config OLPC_XO15_SCI 2469 bool "OLPC XO-1.5 SCI extras" 2470 depends on OLPC && ACPI 2471 select POWER_SUPPLY 2472 ---help--- 2473 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2474 - EC-driven system wakeups 2475 - AC adapter status updates 2476 - Battery status updates 2477 2478config ALIX 2479 bool "PCEngines ALIX System Support (LED setup)" 2480 select GPIOLIB 2481 ---help--- 2482 This option enables system support for the PCEngines ALIX. 2483 At present this just sets up LEDs for GPIO control on 2484 ALIX2/3/6 boards. However, other system specific setup should 2485 get added here. 2486 2487 Note: You must still enable the drivers for GPIO and LED support 2488 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2489 2490 Note: You have to set alix.force=1 for boards with Award BIOS. 2491 2492config NET5501 2493 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2494 select GPIOLIB 2495 ---help--- 2496 This option enables system support for the Soekris Engineering net5501. 2497 2498config GEOS 2499 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2500 select GPIOLIB 2501 depends on DMI 2502 ---help--- 2503 This option enables system support for the Traverse Technologies GEOS. 2504 2505config TS5500 2506 bool "Technologic Systems TS-5500 platform support" 2507 depends on MELAN 2508 select CHECK_SIGNATURE 2509 select NEW_LEDS 2510 select LEDS_CLASS 2511 ---help--- 2512 This option enables system support for the Technologic Systems TS-5500. 2513 2514endif # X86_32 2515 2516config AMD_NB 2517 def_bool y 2518 depends on CPU_SUP_AMD && PCI 2519 2520source "drivers/pcmcia/Kconfig" 2521 2522source "drivers/pci/hotplug/Kconfig" 2523 2524config RAPIDIO 2525 tristate "RapidIO support" 2526 depends on PCI 2527 default n 2528 help 2529 If enabled this option will include drivers and the core 2530 infrastructure code to support RapidIO interconnect devices. 2531 2532source "drivers/rapidio/Kconfig" 2533 2534config X86_SYSFB 2535 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2536 help 2537 Firmwares often provide initial graphics framebuffers so the BIOS, 2538 bootloader or kernel can show basic video-output during boot for 2539 user-guidance and debugging. Historically, x86 used the VESA BIOS 2540 Extensions and EFI-framebuffers for this, which are mostly limited 2541 to x86. 2542 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2543 framebuffers so the new generic system-framebuffer drivers can be 2544 used on x86. If the framebuffer is not compatible with the generic 2545 modes, it is adverticed as fallback platform framebuffer so legacy 2546 drivers like efifb, vesafb and uvesafb can pick it up. 2547 If this option is not selected, all system framebuffers are always 2548 marked as fallback platform framebuffers as usual. 2549 2550 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2551 not be able to pick up generic system framebuffers if this option 2552 is selected. You are highly encouraged to enable simplefb as 2553 replacement if you select this option. simplefb can correctly deal 2554 with generic system framebuffers. But you should still keep vesafb 2555 and others enabled as fallback if a system framebuffer is 2556 incompatible with simplefb. 2557 2558 If unsure, say Y. 2559 2560endmenu 2561 2562 2563menu "Executable file formats / Emulations" 2564 2565source "fs/Kconfig.binfmt" 2566 2567config IA32_EMULATION 2568 bool "IA32 Emulation" 2569 depends on X86_64 2570 select BINFMT_ELF 2571 select COMPAT_BINFMT_ELF 2572 select ARCH_WANT_OLD_COMPAT_IPC 2573 ---help--- 2574 Include code to run legacy 32-bit programs under a 2575 64-bit kernel. You should likely turn this on, unless you're 2576 100% sure that you don't have any 32-bit programs left. 2577 2578config IA32_AOUT 2579 tristate "IA32 a.out support" 2580 depends on IA32_EMULATION 2581 ---help--- 2582 Support old a.out binaries in the 32bit emulation. 2583 2584config X86_X32 2585 bool "x32 ABI for 64-bit mode" 2586 depends on X86_64 2587 ---help--- 2588 Include code to run binaries for the x32 native 32-bit ABI 2589 for 64-bit processors. An x32 process gets access to the 2590 full 64-bit register file and wide data path while leaving 2591 pointers at 32 bits for smaller memory footprint. 2592 2593 You will need a recent binutils (2.22 or later) with 2594 elf32_x86_64 support enabled to compile a kernel with this 2595 option set. 2596 2597config COMPAT 2598 def_bool y 2599 depends on IA32_EMULATION || X86_X32 2600 2601if COMPAT 2602config COMPAT_FOR_U64_ALIGNMENT 2603 def_bool y 2604 2605config SYSVIPC_COMPAT 2606 def_bool y 2607 depends on SYSVIPC 2608 2609config KEYS_COMPAT 2610 def_bool y 2611 depends on KEYS 2612endif 2613 2614endmenu 2615 2616 2617config HAVE_ATOMIC_IOMAP 2618 def_bool y 2619 depends on X86_32 2620 2621config X86_DEV_DMA_OPS 2622 bool 2623 depends on X86_64 || STA2X11 2624 2625config X86_DMA_REMAP 2626 bool 2627 depends on STA2X11 2628 2629config PMC_ATOM 2630 def_bool y 2631 depends on PCI 2632 2633source "net/Kconfig" 2634 2635source "drivers/Kconfig" 2636 2637source "drivers/firmware/Kconfig" 2638 2639source "fs/Kconfig" 2640 2641source "arch/x86/Kconfig.debug" 2642 2643source "security/Kconfig" 2644 2645source "crypto/Kconfig" 2646 2647source "arch/x86/kvm/Kconfig" 2648 2649source "lib/Kconfig" 2650