1# x86 configuration 2mainmenu "Linux Kernel Configuration for x86" 3 4# Select 32 or 64 bit 5config 64BIT 6 bool "64-bit kernel" if ARCH = "x86" 7 default ARCH = "x86_64" 8 help 9 Say yes to build a 64-bit kernel - formerly known as x86_64 10 Say no to build a 32-bit kernel - formerly known as i386 11 12config X86_32 13 def_bool !64BIT 14 15config X86_64 16 def_bool 64BIT 17 18### Arch settings 19config X86 20 def_bool y 21 select HAVE_AOUT if X86_32 22 select HAVE_UNSTABLE_SCHED_CLOCK 23 select HAVE_IDE 24 select HAVE_OPROFILE 25 select HAVE_IOREMAP_PROT 26 select HAVE_KPROBES 27 select ARCH_WANT_OPTIONAL_GPIOLIB 28 select HAVE_KRETPROBES 29 select HAVE_DYNAMIC_FTRACE 30 select HAVE_FTRACE 31 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64) 32 select HAVE_ARCH_KGDB if !X86_VOYAGER 33 select HAVE_ARCH_TRACEHOOK 34 select HAVE_GENERIC_DMA_COHERENT if X86_32 35 select HAVE_EFFICIENT_UNALIGNED_ACCESS 36 37config ARCH_DEFCONFIG 38 string 39 default "arch/x86/configs/i386_defconfig" if X86_32 40 default "arch/x86/configs/x86_64_defconfig" if X86_64 41 42 43config GENERIC_LOCKBREAK 44 def_bool n 45 46config GENERIC_TIME 47 def_bool y 48 49config GENERIC_CMOS_UPDATE 50 def_bool y 51 52config CLOCKSOURCE_WATCHDOG 53 def_bool y 54 55config GENERIC_CLOCKEVENTS 56 def_bool y 57 58config GENERIC_CLOCKEVENTS_BROADCAST 59 def_bool y 60 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 61 62config LOCKDEP_SUPPORT 63 def_bool y 64 65config STACKTRACE_SUPPORT 66 def_bool y 67 68config HAVE_LATENCYTOP_SUPPORT 69 def_bool y 70 71config FAST_CMPXCHG_LOCAL 72 bool 73 default y 74 75config MMU 76 def_bool y 77 78config ZONE_DMA 79 def_bool y 80 81config SBUS 82 bool 83 84config GENERIC_ISA_DMA 85 def_bool y 86 87config GENERIC_IOMAP 88 def_bool y 89 90config GENERIC_BUG 91 def_bool y 92 depends on BUG 93 94config GENERIC_HWEIGHT 95 def_bool y 96 97config GENERIC_GPIO 98 def_bool n 99 100config ARCH_MAY_HAVE_PC_FDC 101 def_bool y 102 103config RWSEM_GENERIC_SPINLOCK 104 def_bool !X86_XADD 105 106config RWSEM_XCHGADD_ALGORITHM 107 def_bool X86_XADD 108 109config ARCH_HAS_ILOG2_U32 110 def_bool n 111 112config ARCH_HAS_ILOG2_U64 113 def_bool n 114 115config ARCH_HAS_CPU_IDLE_WAIT 116 def_bool y 117 118config GENERIC_CALIBRATE_DELAY 119 def_bool y 120 121config GENERIC_TIME_VSYSCALL 122 bool 123 default X86_64 124 125config ARCH_HAS_CPU_RELAX 126 def_bool y 127 128config ARCH_HAS_CACHE_LINE_SIZE 129 def_bool y 130 131config HAVE_SETUP_PER_CPU_AREA 132 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER) 133 134config HAVE_CPUMASK_OF_CPU_MAP 135 def_bool X86_64_SMP 136 137config ARCH_HIBERNATION_POSSIBLE 138 def_bool y 139 depends on !SMP || !X86_VOYAGER 140 141config ARCH_SUSPEND_POSSIBLE 142 def_bool y 143 depends on !X86_VOYAGER 144 145config ZONE_DMA32 146 bool 147 default X86_64 148 149config ARCH_POPULATES_NODE_MAP 150 def_bool y 151 152config AUDIT_ARCH 153 bool 154 default X86_64 155 156config ARCH_SUPPORTS_OPTIMIZED_INLINING 157 def_bool y 158 159# Use the generic interrupt handling code in kernel/irq/: 160config GENERIC_HARDIRQS 161 bool 162 default y 163 164config GENERIC_IRQ_PROBE 165 bool 166 default y 167 168config GENERIC_PENDING_IRQ 169 bool 170 depends on GENERIC_HARDIRQS && SMP 171 default y 172 173config X86_SMP 174 bool 175 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64) 176 select USE_GENERIC_SMP_HELPERS 177 default y 178 179config X86_32_SMP 180 def_bool y 181 depends on X86_32 && SMP 182 183config X86_64_SMP 184 def_bool y 185 depends on X86_64 && SMP 186 187config X86_HT 188 bool 189 depends on SMP 190 depends on (X86_32 && !X86_VOYAGER) || X86_64 191 default y 192 193config X86_BIOS_REBOOT 194 bool 195 depends on !X86_VOYAGER 196 default y 197 198config X86_TRAMPOLINE 199 bool 200 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP) 201 default y 202 203config KTIME_SCALAR 204 def_bool X86_32 205source "init/Kconfig" 206 207menu "Processor type and features" 208 209source "kernel/time/Kconfig" 210 211config SMP 212 bool "Symmetric multi-processing support" 213 ---help--- 214 This enables support for systems with more than one CPU. If you have 215 a system with only one CPU, like most personal computers, say N. If 216 you have a system with more than one CPU, say Y. 217 218 If you say N here, the kernel will run on single and multiprocessor 219 machines, but will use only one CPU of a multiprocessor machine. If 220 you say Y here, the kernel will run on many, but not all, 221 singleprocessor machines. On a singleprocessor machine, the kernel 222 will run faster if you say N here. 223 224 Note that if you say Y here and choose architecture "586" or 225 "Pentium" under "Processor family", the kernel will not work on 486 226 architectures. Similarly, multiprocessor kernels for the "PPro" 227 architecture may not work on all Pentium based boards. 228 229 People using multiprocessor machines who say Y here should also say 230 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 231 Management" code will be disabled if you say Y here. 232 233 See also <file:Documentation/i386/IO-APIC.txt>, 234 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 235 <http://www.tldp.org/docs.html#howto>. 236 237 If you don't know what to do here, say N. 238 239config X86_FIND_SMP_CONFIG 240 def_bool y 241 depends on X86_MPPARSE || X86_VOYAGER 242 243if ACPI 244config X86_MPPARSE 245 def_bool y 246 bool "Enable MPS table" 247 depends on X86_LOCAL_APIC 248 help 249 For old smp systems that do not have proper acpi support. Newer systems 250 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 251endif 252 253if !ACPI 254config X86_MPPARSE 255 def_bool y 256 depends on X86_LOCAL_APIC 257endif 258 259choice 260 prompt "Subarchitecture Type" 261 default X86_PC 262 263config X86_PC 264 bool "PC-compatible" 265 help 266 Choose this option if your computer is a standard PC or compatible. 267 268config X86_ELAN 269 bool "AMD Elan" 270 depends on X86_32 271 help 272 Select this for an AMD Elan processor. 273 274 Do not use this option for K6/Athlon/Opteron processors! 275 276 If unsure, choose "PC-compatible" instead. 277 278config X86_VOYAGER 279 bool "Voyager (NCR)" 280 depends on X86_32 && (SMP || BROKEN) && !PCI 281 help 282 Voyager is an MCA-based 32-way capable SMP architecture proprietary 283 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based. 284 285 *** WARNING *** 286 287 If you do not specifically know you have a Voyager based machine, 288 say N here, otherwise the kernel you build will not be bootable. 289 290config X86_GENERICARCH 291 bool "Generic architecture" 292 depends on X86_32 293 help 294 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 295 subarchitectures. It is intended for a generic binary kernel. 296 if you select them all, kernel will probe it one by one. and will 297 fallback to default. 298 299if X86_GENERICARCH 300 301config X86_NUMAQ 302 bool "NUMAQ (IBM/Sequent)" 303 depends on SMP && X86_32 && PCI && X86_MPPARSE 304 select NUMA 305 help 306 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 307 NUMA multiquad box. This changes the way that processors are 308 bootstrapped, and uses Clustered Logical APIC addressing mode instead 309 of Flat Logical. You will need a new lynxer.elf file to flash your 310 firmware with - send email to <Martin.Bligh@us.ibm.com>. 311 312config X86_SUMMIT 313 bool "Summit/EXA (IBM x440)" 314 depends on X86_32 && SMP 315 help 316 This option is needed for IBM systems that use the Summit/EXA chipset. 317 In particular, it is needed for the x440. 318 319config X86_ES7000 320 bool "Support for Unisys ES7000 IA32 series" 321 depends on X86_32 && SMP 322 help 323 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 324 supposed to run on an IA32-based Unisys ES7000 system. 325 326config X86_BIGSMP 327 bool "Support for big SMP systems with more than 8 CPUs" 328 depends on X86_32 && SMP 329 help 330 This option is needed for the systems that have more than 8 CPUs 331 and if the system is not of any sub-arch type above. 332 333endif 334 335config X86_VSMP 336 bool "Support for ScaleMP vSMP" 337 select PARAVIRT 338 depends on X86_64 && PCI 339 help 340 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 341 supposed to run on these EM64T-based machines. Only choose this option 342 if you have one of these machines. 343 344endchoice 345 346config X86_VISWS 347 bool "SGI 320/540 (Visual Workstation)" 348 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT 349 help 350 The SGI Visual Workstation series is an IA32-based workstation 351 based on SGI systems chips with some legacy PC hardware attached. 352 353 Say Y here to create a kernel to run on the SGI 320 or 540. 354 355 A kernel compiled for the Visual Workstation will run on general 356 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 357 358config X86_RDC321X 359 bool "RDC R-321x SoC" 360 depends on X86_32 361 select M486 362 select X86_REBOOTFIXUPS 363 help 364 This option is needed for RDC R-321x system-on-chip, also known 365 as R-8610-(G). 366 If you don't have one of these chips, you should say N here. 367 368config SCHED_NO_NO_OMIT_FRAME_POINTER 369 def_bool y 370 prompt "Single-depth WCHAN output" 371 depends on X86_32 372 help 373 Calculate simpler /proc/<PID>/wchan values. If this option 374 is disabled then wchan values will recurse back to the 375 caller function. This provides more accurate wchan values, 376 at the expense of slightly more scheduling overhead. 377 378 If in doubt, say "Y". 379 380menuconfig PARAVIRT_GUEST 381 bool "Paravirtualized guest support" 382 help 383 Say Y here to get to see options related to running Linux under 384 various hypervisors. This option alone does not add any kernel code. 385 386 If you say N, all options in this submenu will be skipped and disabled. 387 388if PARAVIRT_GUEST 389 390source "arch/x86/xen/Kconfig" 391 392config VMI 393 bool "VMI Guest support" 394 select PARAVIRT 395 depends on X86_32 396 depends on !X86_VOYAGER 397 help 398 VMI provides a paravirtualized interface to the VMware ESX server 399 (it could be used by other hypervisors in theory too, but is not 400 at the moment), by linking the kernel to a GPL-ed ROM module 401 provided by the hypervisor. 402 403config KVM_CLOCK 404 bool "KVM paravirtualized clock" 405 select PARAVIRT 406 select PARAVIRT_CLOCK 407 depends on !X86_VOYAGER 408 help 409 Turning on this option will allow you to run a paravirtualized clock 410 when running over the KVM hypervisor. Instead of relying on a PIT 411 (or probably other) emulation by the underlying device model, the host 412 provides the guest with timing infrastructure such as time of day, and 413 system time 414 415config KVM_GUEST 416 bool "KVM Guest support" 417 select PARAVIRT 418 depends on !X86_VOYAGER 419 help 420 This option enables various optimizations for running under the KVM 421 hypervisor. 422 423source "arch/x86/lguest/Kconfig" 424 425config PARAVIRT 426 bool "Enable paravirtualization code" 427 depends on !X86_VOYAGER 428 help 429 This changes the kernel so it can modify itself when it is run 430 under a hypervisor, potentially improving performance significantly 431 over full virtualization. However, when run without a hypervisor 432 the kernel is theoretically slower and slightly larger. 433 434config PARAVIRT_CLOCK 435 bool 436 default n 437 438endif 439 440config PARAVIRT_DEBUG 441 bool "paravirt-ops debugging" 442 depends on PARAVIRT && DEBUG_KERNEL 443 help 444 Enable to debug paravirt_ops internals. Specifically, BUG if 445 a paravirt_op is missing when it is called. 446 447config MEMTEST 448 bool "Memtest" 449 help 450 This option adds a kernel parameter 'memtest', which allows memtest 451 to be set. 452 memtest=0, mean disabled; -- default 453 memtest=1, mean do 1 test pattern; 454 ... 455 memtest=4, mean do 4 test patterns. 456 If you are unsure how to answer this question, answer N. 457 458config X86_SUMMIT_NUMA 459 def_bool y 460 depends on X86_32 && NUMA && X86_GENERICARCH 461 462config X86_CYCLONE_TIMER 463 def_bool y 464 depends on X86_GENERICARCH 465 466config ES7000_CLUSTERED_APIC 467 def_bool y 468 depends on SMP && X86_ES7000 && MPENTIUMIII 469 470source "arch/x86/Kconfig.cpu" 471 472config HPET_TIMER 473 def_bool X86_64 474 prompt "HPET Timer Support" if X86_32 475 help 476 Use the IA-PC HPET (High Precision Event Timer) to manage 477 time in preference to the PIT and RTC, if a HPET is 478 present. 479 HPET is the next generation timer replacing legacy 8254s. 480 The HPET provides a stable time base on SMP 481 systems, unlike the TSC, but it is more expensive to access, 482 as it is off-chip. You can find the HPET spec at 483 <http://www.intel.com/hardwaredesign/hpetspec.htm>. 484 485 You can safely choose Y here. However, HPET will only be 486 activated if the platform and the BIOS support this feature. 487 Otherwise the 8254 will be used for timing services. 488 489 Choose N to continue using the legacy 8254 timer. 490 491config HPET_EMULATE_RTC 492 def_bool y 493 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 494 495# Mark as embedded because too many people got it wrong. 496# The code disables itself when not needed. 497config DMI 498 default y 499 bool "Enable DMI scanning" if EMBEDDED 500 help 501 Enabled scanning of DMI to identify machine quirks. Say Y 502 here unless you have verified that your setup is not 503 affected by entries in the DMI blacklist. Required by PNP 504 BIOS code. 505 506config GART_IOMMU 507 bool "GART IOMMU support" if EMBEDDED 508 default y 509 select SWIOTLB 510 select AGP 511 depends on X86_64 && PCI 512 help 513 Support for full DMA access of devices with 32bit memory access only 514 on systems with more than 3GB. This is usually needed for USB, 515 sound, many IDE/SATA chipsets and some other devices. 516 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 517 based hardware IOMMU and a software bounce buffer based IOMMU used 518 on Intel systems and as fallback. 519 The code is only active when needed (enough memory and limited 520 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 521 too. 522 523config CALGARY_IOMMU 524 bool "IBM Calgary IOMMU support" 525 select SWIOTLB 526 depends on X86_64 && PCI && EXPERIMENTAL 527 help 528 Support for hardware IOMMUs in IBM's xSeries x366 and x460 529 systems. Needed to run systems with more than 3GB of memory 530 properly with 32-bit PCI devices that do not support DAC 531 (Double Address Cycle). Calgary also supports bus level 532 isolation, where all DMAs pass through the IOMMU. This 533 prevents them from going anywhere except their intended 534 destination. This catches hard-to-find kernel bugs and 535 mis-behaving drivers and devices that do not use the DMA-API 536 properly to set up their DMA buffers. The IOMMU can be 537 turned off at boot time with the iommu=off parameter. 538 Normally the kernel will make the right choice by itself. 539 If unsure, say Y. 540 541config CALGARY_IOMMU_ENABLED_BY_DEFAULT 542 def_bool y 543 prompt "Should Calgary be enabled by default?" 544 depends on CALGARY_IOMMU 545 help 546 Should Calgary be enabled by default? if you choose 'y', Calgary 547 will be used (if it exists). If you choose 'n', Calgary will not be 548 used even if it exists. If you choose 'n' and would like to use 549 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 550 If unsure, say Y. 551 552config AMD_IOMMU 553 bool "AMD IOMMU support" 554 select SWIOTLB 555 select PCI_MSI 556 depends on X86_64 && PCI && ACPI 557 help 558 With this option you can enable support for AMD IOMMU hardware in 559 your system. An IOMMU is a hardware component which provides 560 remapping of DMA memory accesses from devices. With an AMD IOMMU you 561 can isolate the the DMA memory of different devices and protect the 562 system from misbehaving device drivers or hardware. 563 564 You can find out if your system has an AMD IOMMU if you look into 565 your BIOS for an option to enable it or if you have an IVRS ACPI 566 table. 567 568# need this always selected by IOMMU for the VIA workaround 569config SWIOTLB 570 bool 571 help 572 Support for software bounce buffers used on x86-64 systems 573 which don't have a hardware IOMMU (e.g. the current generation 574 of Intel's x86-64 CPUs). Using this PCI devices which can only 575 access 32-bits of memory can be used on systems with more than 576 3 GB of memory. If unsure, say Y. 577 578config IOMMU_HELPER 579 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 580 581config MAXSMP 582 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 583 depends on X86_64 && SMP && BROKEN 584 default n 585 help 586 Configure maximum number of CPUS and NUMA Nodes for this architecture. 587 If unsure, say N. 588 589config NR_CPUS 590 int "Maximum number of CPUs (2-512)" if !MAXSMP 591 range 2 512 592 depends on SMP 593 default "4096" if MAXSMP 594 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000 595 default "8" 596 help 597 This allows you to specify the maximum number of CPUs which this 598 kernel will support. The maximum supported value is 512 and the 599 minimum value which makes sense is 2. 600 601 This is purely to save memory - each supported CPU adds 602 approximately eight kilobytes to the kernel image. 603 604config SCHED_SMT 605 bool "SMT (Hyperthreading) scheduler support" 606 depends on X86_HT 607 help 608 SMT scheduler support improves the CPU scheduler's decision making 609 when dealing with Intel Pentium 4 chips with HyperThreading at a 610 cost of slightly increased overhead in some places. If unsure say 611 N here. 612 613config SCHED_MC 614 def_bool y 615 prompt "Multi-core scheduler support" 616 depends on X86_HT 617 help 618 Multi-core scheduler support improves the CPU scheduler's decision 619 making when dealing with multi-core CPU chips at a cost of slightly 620 increased overhead in some places. If unsure say N here. 621 622source "kernel/Kconfig.preempt" 623 624config X86_UP_APIC 625 bool "Local APIC support on uniprocessors" 626 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH) 627 help 628 A local APIC (Advanced Programmable Interrupt Controller) is an 629 integrated interrupt controller in the CPU. If you have a single-CPU 630 system which has a processor with a local APIC, you can say Y here to 631 enable and use it. If you say Y here even though your machine doesn't 632 have a local APIC, then the kernel will still run with no slowdown at 633 all. The local APIC supports CPU-generated self-interrupts (timer, 634 performance counters), and the NMI watchdog which detects hard 635 lockups. 636 637config X86_UP_IOAPIC 638 bool "IO-APIC support on uniprocessors" 639 depends on X86_UP_APIC 640 help 641 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 642 SMP-capable replacement for PC-style interrupt controllers. Most 643 SMP systems and many recent uniprocessor systems have one. 644 645 If you have a single-CPU system with an IO-APIC, you can say Y here 646 to use it. If you say Y here even though your machine doesn't have 647 an IO-APIC, then the kernel will still run with no slowdown at all. 648 649config X86_LOCAL_APIC 650 def_bool y 651 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH)) 652 653config X86_IO_APIC 654 def_bool y 655 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH)) 656 657config X86_VISWS_APIC 658 def_bool y 659 depends on X86_32 && X86_VISWS 660 661config X86_MCE 662 bool "Machine Check Exception" 663 depends on !X86_VOYAGER 664 ---help--- 665 Machine Check Exception support allows the processor to notify the 666 kernel if it detects a problem (e.g. overheating, component failure). 667 The action the kernel takes depends on the severity of the problem, 668 ranging from a warning message on the console, to halting the machine. 669 Your processor must be a Pentium or newer to support this - check the 670 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 671 have a design flaw which leads to false MCE events - hence MCE is 672 disabled on all P5 processors, unless explicitly enabled with "mce" 673 as a boot argument. Similarly, if MCE is built in and creates a 674 problem on some new non-standard machine, you can boot with "nomce" 675 to disable it. MCE support simply ignores non-MCE processors like 676 the 386 and 486, so nearly everyone can say Y here. 677 678config X86_MCE_INTEL 679 def_bool y 680 prompt "Intel MCE features" 681 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 682 help 683 Additional support for intel specific MCE features such as 684 the thermal monitor. 685 686config X86_MCE_AMD 687 def_bool y 688 prompt "AMD MCE features" 689 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 690 help 691 Additional support for AMD specific MCE features such as 692 the DRAM Error Threshold. 693 694config X86_MCE_NONFATAL 695 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 696 depends on X86_32 && X86_MCE 697 help 698 Enabling this feature starts a timer that triggers every 5 seconds which 699 will look at the machine check registers to see if anything happened. 700 Non-fatal problems automatically get corrected (but still logged). 701 Disable this if you don't want to see these messages. 702 Seeing the messages this option prints out may be indicative of dying 703 or out-of-spec (ie, overclocked) hardware. 704 This option only does something on certain CPUs. 705 (AMD Athlon/Duron and Intel Pentium 4) 706 707config X86_MCE_P4THERMAL 708 bool "check for P4 thermal throttling interrupt." 709 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) 710 help 711 Enabling this feature will cause a message to be printed when the P4 712 enters thermal throttling. 713 714config VM86 715 bool "Enable VM86 support" if EMBEDDED 716 default y 717 depends on X86_32 718 help 719 This option is required by programs like DOSEMU to run 16-bit legacy 720 code on X86 processors. It also may be needed by software like 721 XFree86 to initialize some video cards via BIOS. Disabling this 722 option saves about 6k. 723 724config TOSHIBA 725 tristate "Toshiba Laptop support" 726 depends on X86_32 727 ---help--- 728 This adds a driver to safely access the System Management Mode of 729 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 730 not work on models with a Phoenix BIOS. The System Management Mode 731 is used to set the BIOS and power saving options on Toshiba portables. 732 733 For information on utilities to make use of this driver see the 734 Toshiba Linux utilities web site at: 735 <http://www.buzzard.org.uk/toshiba/>. 736 737 Say Y if you intend to run this kernel on a Toshiba portable. 738 Say N otherwise. 739 740config I8K 741 tristate "Dell laptop support" 742 ---help--- 743 This adds a driver to safely access the System Management Mode 744 of the CPU on the Dell Inspiron 8000. The System Management Mode 745 is used to read cpu temperature and cooling fan status and to 746 control the fans on the I8K portables. 747 748 This driver has been tested only on the Inspiron 8000 but it may 749 also work with other Dell laptops. You can force loading on other 750 models by passing the parameter `force=1' to the module. Use at 751 your own risk. 752 753 For information on utilities to make use of this driver see the 754 I8K Linux utilities web site at: 755 <http://people.debian.org/~dz/i8k/> 756 757 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 758 Say N otherwise. 759 760config X86_REBOOTFIXUPS 761 def_bool n 762 prompt "Enable X86 board specific fixups for reboot" 763 depends on X86_32 && X86 764 ---help--- 765 This enables chipset and/or board specific fixups to be done 766 in order to get reboot to work correctly. This is only needed on 767 some combinations of hardware and BIOS. The symptom, for which 768 this config is intended, is when reboot ends with a stalled/hung 769 system. 770 771 Currently, the only fixup is for the Geode machines using 772 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 773 774 Say Y if you want to enable the fixup. Currently, it's safe to 775 enable this option even if you don't need it. 776 Say N otherwise. 777 778config MICROCODE 779 tristate "/dev/cpu/microcode - microcode support" 780 select FW_LOADER 781 ---help--- 782 If you say Y here, you will be able to update the microcode on 783 certain Intel and AMD processors. The Intel support is for the 784 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 785 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 786 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 787 You will obviously need the actual microcode binary data itself 788 which is not shipped with the Linux kernel. 789 790 This option selects the general module only, you need to select 791 at least one vendor specific module as well. 792 793 To compile this driver as a module, choose M here: the 794 module will be called microcode. 795 796config MICROCODE_INTEL 797 bool "Intel microcode patch loading support" 798 depends on MICROCODE 799 default MICROCODE 800 select FW_LOADER 801 --help--- 802 This options enables microcode patch loading support for Intel 803 processors. 804 805 For latest news and information on obtaining all the required 806 Intel ingredients for this driver, check: 807 <http://www.urbanmyth.org/microcode/>. 808 809config MICROCODE_AMD 810 bool "AMD microcode patch loading support" 811 depends on MICROCODE 812 select FW_LOADER 813 --help--- 814 If you select this option, microcode patch loading support for AMD 815 processors will be enabled. 816 817 config MICROCODE_OLD_INTERFACE 818 def_bool y 819 depends on MICROCODE 820 821config X86_MSR 822 tristate "/dev/cpu/*/msr - Model-specific register support" 823 help 824 This device gives privileged processes access to the x86 825 Model-Specific Registers (MSRs). It is a character device with 826 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 827 MSR accesses are directed to a specific CPU on multi-processor 828 systems. 829 830config X86_CPUID 831 tristate "/dev/cpu/*/cpuid - CPU information support" 832 help 833 This device gives processes access to the x86 CPUID instruction to 834 be executed on a specific processor. It is a character device 835 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 836 /dev/cpu/31/cpuid. 837 838choice 839 prompt "High Memory Support" 840 default HIGHMEM4G if !X86_NUMAQ 841 default HIGHMEM64G if X86_NUMAQ 842 depends on X86_32 843 844config NOHIGHMEM 845 bool "off" 846 depends on !X86_NUMAQ 847 ---help--- 848 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 849 However, the address space of 32-bit x86 processors is only 4 850 Gigabytes large. That means that, if you have a large amount of 851 physical memory, not all of it can be "permanently mapped" by the 852 kernel. The physical memory that's not permanently mapped is called 853 "high memory". 854 855 If you are compiling a kernel which will never run on a machine with 856 more than 1 Gigabyte total physical RAM, answer "off" here (default 857 choice and suitable for most users). This will result in a "3GB/1GB" 858 split: 3GB are mapped so that each process sees a 3GB virtual memory 859 space and the remaining part of the 4GB virtual memory space is used 860 by the kernel to permanently map as much physical memory as 861 possible. 862 863 If the machine has between 1 and 4 Gigabytes physical RAM, then 864 answer "4GB" here. 865 866 If more than 4 Gigabytes is used then answer "64GB" here. This 867 selection turns Intel PAE (Physical Address Extension) mode on. 868 PAE implements 3-level paging on IA32 processors. PAE is fully 869 supported by Linux, PAE mode is implemented on all recent Intel 870 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 871 then the kernel will not boot on CPUs that don't support PAE! 872 873 The actual amount of total physical memory will either be 874 auto detected or can be forced by using a kernel command line option 875 such as "mem=256M". (Try "man bootparam" or see the documentation of 876 your boot loader (lilo or loadlin) about how to pass options to the 877 kernel at boot time.) 878 879 If unsure, say "off". 880 881config HIGHMEM4G 882 bool "4GB" 883 depends on !X86_NUMAQ 884 help 885 Select this if you have a 32-bit processor and between 1 and 4 886 gigabytes of physical RAM. 887 888config HIGHMEM64G 889 bool "64GB" 890 depends on !M386 && !M486 891 select X86_PAE 892 help 893 Select this if you have a 32-bit processor and more than 4 894 gigabytes of physical RAM. 895 896endchoice 897 898choice 899 depends on EXPERIMENTAL 900 prompt "Memory split" if EMBEDDED 901 default VMSPLIT_3G 902 depends on X86_32 903 help 904 Select the desired split between kernel and user memory. 905 906 If the address range available to the kernel is less than the 907 physical memory installed, the remaining memory will be available 908 as "high memory". Accessing high memory is a little more costly 909 than low memory, as it needs to be mapped into the kernel first. 910 Note that increasing the kernel address space limits the range 911 available to user programs, making the address space there 912 tighter. Selecting anything other than the default 3G/1G split 913 will also likely make your kernel incompatible with binary-only 914 kernel modules. 915 916 If you are not absolutely sure what you are doing, leave this 917 option alone! 918 919 config VMSPLIT_3G 920 bool "3G/1G user/kernel split" 921 config VMSPLIT_3G_OPT 922 depends on !X86_PAE 923 bool "3G/1G user/kernel split (for full 1G low memory)" 924 config VMSPLIT_2G 925 bool "2G/2G user/kernel split" 926 config VMSPLIT_2G_OPT 927 depends on !X86_PAE 928 bool "2G/2G user/kernel split (for full 2G low memory)" 929 config VMSPLIT_1G 930 bool "1G/3G user/kernel split" 931endchoice 932 933config PAGE_OFFSET 934 hex 935 default 0xB0000000 if VMSPLIT_3G_OPT 936 default 0x80000000 if VMSPLIT_2G 937 default 0x78000000 if VMSPLIT_2G_OPT 938 default 0x40000000 if VMSPLIT_1G 939 default 0xC0000000 940 depends on X86_32 941 942config HIGHMEM 943 def_bool y 944 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 945 946config X86_PAE 947 def_bool n 948 prompt "PAE (Physical Address Extension) Support" 949 depends on X86_32 && !HIGHMEM4G 950 select RESOURCES_64BIT 951 help 952 PAE is required for NX support, and furthermore enables 953 larger swapspace support for non-overcommit purposes. It 954 has the cost of more pagetable lookup overhead, and also 955 consumes more pagetable space per process. 956 957# Common NUMA Features 958config NUMA 959 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)" 960 depends on SMP 961 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 962 default n if X86_PC 963 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 964 help 965 Enable NUMA (Non Uniform Memory Access) support. 966 The kernel will try to allocate memory used by a CPU on the 967 local memory controller of the CPU and add some more 968 NUMA awareness to the kernel. 969 970 For 32-bit this is currently highly experimental and should be only 971 used for kernel development. It might also cause boot failures. 972 For 64-bit this is recommended on all multiprocessor Opteron systems. 973 If the system is EM64T, you should say N unless your system is 974 EM64T NUMA. 975 976comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 977 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 978 979config K8_NUMA 980 def_bool y 981 prompt "Old style AMD Opteron NUMA detection" 982 depends on X86_64 && NUMA && PCI 983 help 984 Enable K8 NUMA node topology detection. You should say Y here if 985 you have a multi processor AMD K8 system. This uses an old 986 method to read the NUMA configuration directly from the builtin 987 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 988 instead, which also takes priority if both are compiled in. 989 990config X86_64_ACPI_NUMA 991 def_bool y 992 prompt "ACPI NUMA detection" 993 depends on X86_64 && NUMA && ACPI && PCI 994 select ACPI_NUMA 995 help 996 Enable ACPI SRAT based node topology detection. 997 998# Some NUMA nodes have memory ranges that span 999# other nodes. Even though a pfn is valid and 1000# between a node's start and end pfns, it may not 1001# reside on that node. See memmap_init_zone() 1002# for details. 1003config NODES_SPAN_OTHER_NODES 1004 def_bool y 1005 depends on X86_64_ACPI_NUMA 1006 1007config NUMA_EMU 1008 bool "NUMA emulation" 1009 depends on X86_64 && NUMA 1010 help 1011 Enable NUMA emulation. A flat machine will be split 1012 into virtual nodes when booted with "numa=fake=N", where N is the 1013 number of nodes. This is only useful for debugging. 1014 1015config NODES_SHIFT 1016 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1017 range 1 9 if X86_64 1018 default "9" if MAXSMP 1019 default "6" if X86_64 1020 default "4" if X86_NUMAQ 1021 default "3" 1022 depends on NEED_MULTIPLE_NODES 1023 help 1024 Specify the maximum number of NUMA Nodes available on the target 1025 system. Increases memory reserved to accomodate various tables. 1026 1027config HAVE_ARCH_BOOTMEM_NODE 1028 def_bool y 1029 depends on X86_32 && NUMA 1030 1031config ARCH_HAVE_MEMORY_PRESENT 1032 def_bool y 1033 depends on X86_32 && DISCONTIGMEM 1034 1035config NEED_NODE_MEMMAP_SIZE 1036 def_bool y 1037 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1038 1039config HAVE_ARCH_ALLOC_REMAP 1040 def_bool y 1041 depends on X86_32 && NUMA 1042 1043config ARCH_FLATMEM_ENABLE 1044 def_bool y 1045 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1046 1047config ARCH_DISCONTIGMEM_ENABLE 1048 def_bool y 1049 depends on NUMA && X86_32 1050 1051config ARCH_DISCONTIGMEM_DEFAULT 1052 def_bool y 1053 depends on NUMA && X86_32 1054 1055config ARCH_SPARSEMEM_DEFAULT 1056 def_bool y 1057 depends on X86_64 1058 1059config ARCH_SPARSEMEM_ENABLE 1060 def_bool y 1061 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) || X86_GENERICARCH 1062 select SPARSEMEM_STATIC if X86_32 1063 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1064 1065config ARCH_SELECT_MEMORY_MODEL 1066 def_bool y 1067 depends on ARCH_SPARSEMEM_ENABLE 1068 1069config ARCH_MEMORY_PROBE 1070 def_bool X86_64 1071 depends on MEMORY_HOTPLUG 1072 1073source "mm/Kconfig" 1074 1075config HIGHPTE 1076 bool "Allocate 3rd-level pagetables from highmem" 1077 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1078 help 1079 The VM uses one page table entry for each page of physical memory. 1080 For systems with a lot of RAM, this can be wasteful of precious 1081 low memory. Setting this option will put user-space page table 1082 entries in high memory. 1083 1084config X86_CHECK_BIOS_CORRUPTION 1085 bool "Check for low memory corruption" 1086 help 1087 Periodically check for memory corruption in low memory, which 1088 is suspected to be caused by BIOS. Even when enabled in the 1089 configuration, it is disabled at runtime. Enable it by 1090 setting "memory_corruption_check=1" on the kernel command 1091 line. By default it scans the low 64k of memory every 60 1092 seconds; see the memory_corruption_check_size and 1093 memory_corruption_check_period parameters in 1094 Documentation/kernel-parameters.txt to adjust this. 1095 1096 When enabled with the default parameters, this option has 1097 almost no overhead, as it reserves a relatively small amount 1098 of memory and scans it infrequently. It both detects corruption 1099 and prevents it from affecting the running system. 1100 1101 It is, however, intended as a diagnostic tool; if repeatable 1102 BIOS-originated corruption always affects the same memory, 1103 you can use memmap= to prevent the kernel from using that 1104 memory. 1105 1106config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1107 bool "Set the default setting of memory_corruption_check" 1108 depends on X86_CHECK_BIOS_CORRUPTION 1109 default y 1110 help 1111 Set whether the default state of memory_corruption_check is 1112 on or off. 1113 1114config X86_RESERVE_LOW_64K 1115 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1116 default y 1117 help 1118 Reserve the first 64K of physical RAM on BIOSes that are known 1119 to potentially corrupt that memory range. A numbers of BIOSes are 1120 known to utilize this area during suspend/resume, so it must not 1121 be used by the kernel. 1122 1123 Set this to N if you are absolutely sure that you trust the BIOS 1124 to get all its memory reservations and usages right. 1125 1126 If you have doubts about the BIOS (e.g. suspend/resume does not 1127 work or there's kernel crashes after certain hardware hotplug 1128 events) and it's not AMI or Phoenix, then you might want to enable 1129 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1130 corruption patterns. 1131 1132 Say Y if unsure. 1133 1134config MATH_EMULATION 1135 bool 1136 prompt "Math emulation" if X86_32 1137 ---help--- 1138 Linux can emulate a math coprocessor (used for floating point 1139 operations) if you don't have one. 486DX and Pentium processors have 1140 a math coprocessor built in, 486SX and 386 do not, unless you added 1141 a 487DX or 387, respectively. (The messages during boot time can 1142 give you some hints here ["man dmesg"].) Everyone needs either a 1143 coprocessor or this emulation. 1144 1145 If you don't have a math coprocessor, you need to say Y here; if you 1146 say Y here even though you have a coprocessor, the coprocessor will 1147 be used nevertheless. (This behavior can be changed with the kernel 1148 command line option "no387", which comes handy if your coprocessor 1149 is broken. Try "man bootparam" or see the documentation of your boot 1150 loader (lilo or loadlin) about how to pass options to the kernel at 1151 boot time.) This means that it is a good idea to say Y here if you 1152 intend to use this kernel on different machines. 1153 1154 More information about the internals of the Linux math coprocessor 1155 emulation can be found in <file:arch/x86/math-emu/README>. 1156 1157 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1158 kernel, it won't hurt. 1159 1160config MTRR 1161 bool "MTRR (Memory Type Range Register) support" 1162 ---help--- 1163 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1164 the Memory Type Range Registers (MTRRs) may be used to control 1165 processor access to memory ranges. This is most useful if you have 1166 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1167 allows bus write transfers to be combined into a larger transfer 1168 before bursting over the PCI/AGP bus. This can increase performance 1169 of image write operations 2.5 times or more. Saying Y here creates a 1170 /proc/mtrr file which may be used to manipulate your processor's 1171 MTRRs. Typically the X server should use this. 1172 1173 This code has a reasonably generic interface so that similar 1174 control registers on other processors can be easily supported 1175 as well: 1176 1177 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1178 Registers (ARRs) which provide a similar functionality to MTRRs. For 1179 these, the ARRs are used to emulate the MTRRs. 1180 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1181 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1182 write-combining. All of these processors are supported by this code 1183 and it makes sense to say Y here if you have one of them. 1184 1185 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1186 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1187 can lead to all sorts of problems, so it's good to say Y here. 1188 1189 You can safely say Y even if your machine doesn't have MTRRs, you'll 1190 just add about 9 KB to your kernel. 1191 1192 See <file:Documentation/x86/mtrr.txt> for more information. 1193 1194config MTRR_SANITIZER 1195 def_bool y 1196 prompt "MTRR cleanup support" 1197 depends on MTRR 1198 help 1199 Convert MTRR layout from continuous to discrete, so X drivers can 1200 add writeback entries. 1201 1202 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1203 The largest mtrr entry size for a continous block can be set with 1204 mtrr_chunk_size. 1205 1206 If unsure, say Y. 1207 1208config MTRR_SANITIZER_ENABLE_DEFAULT 1209 int "MTRR cleanup enable value (0-1)" 1210 range 0 1 1211 default "0" 1212 depends on MTRR_SANITIZER 1213 help 1214 Enable mtrr cleanup default value 1215 1216config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1217 int "MTRR cleanup spare reg num (0-7)" 1218 range 0 7 1219 default "1" 1220 depends on MTRR_SANITIZER 1221 help 1222 mtrr cleanup spare entries default, it can be changed via 1223 mtrr_spare_reg_nr=N on the kernel command line. 1224 1225config X86_PAT 1226 bool 1227 prompt "x86 PAT support" 1228 depends on MTRR 1229 help 1230 Use PAT attributes to setup page level cache control. 1231 1232 PATs are the modern equivalents of MTRRs and are much more 1233 flexible than MTRRs. 1234 1235 Say N here if you see bootup problems (boot crash, boot hang, 1236 spontaneous reboots) or a non-working video driver. 1237 1238 If unsure, say Y. 1239 1240config EFI 1241 def_bool n 1242 prompt "EFI runtime service support" 1243 depends on ACPI 1244 ---help--- 1245 This enables the kernel to use EFI runtime services that are 1246 available (such as the EFI variable services). 1247 1248 This option is only useful on systems that have EFI firmware. 1249 In addition, you should use the latest ELILO loader available 1250 at <http://elilo.sourceforge.net> in order to take advantage 1251 of EFI runtime services. However, even with this option, the 1252 resultant kernel should continue to boot on existing non-EFI 1253 platforms. 1254 1255config IRQBALANCE 1256 def_bool y 1257 prompt "Enable kernel irq balancing" 1258 depends on X86_32 && SMP && X86_IO_APIC 1259 help 1260 The default yes will allow the kernel to do irq load balancing. 1261 Saying no will keep the kernel from doing irq load balancing. 1262 1263config SECCOMP 1264 def_bool y 1265 prompt "Enable seccomp to safely compute untrusted bytecode" 1266 help 1267 This kernel feature is useful for number crunching applications 1268 that may need to compute untrusted bytecode during their 1269 execution. By using pipes or other transports made available to 1270 the process as file descriptors supporting the read/write 1271 syscalls, it's possible to isolate those applications in 1272 their own address space using seccomp. Once seccomp is 1273 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1274 and the task is only allowed to execute a few safe syscalls 1275 defined by each seccomp mode. 1276 1277 If unsure, say Y. Only embedded should say N here. 1278 1279config CC_STACKPROTECTOR 1280 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1281 depends on X86_64 && EXPERIMENTAL && BROKEN 1282 help 1283 This option turns on the -fstack-protector GCC feature. This 1284 feature puts, at the beginning of critical functions, a canary 1285 value on the stack just before the return address, and validates 1286 the value just before actually returning. Stack based buffer 1287 overflows (that need to overwrite this return address) now also 1288 overwrite the canary, which gets detected and the attack is then 1289 neutralized via a kernel panic. 1290 1291 This feature requires gcc version 4.2 or above, or a distribution 1292 gcc with the feature backported. Older versions are automatically 1293 detected and for those versions, this configuration option is ignored. 1294 1295config CC_STACKPROTECTOR_ALL 1296 bool "Use stack-protector for all functions" 1297 depends on CC_STACKPROTECTOR 1298 help 1299 Normally, GCC only inserts the canary value protection for 1300 functions that use large-ish on-stack buffers. By enabling 1301 this option, GCC will be asked to do this for ALL functions. 1302 1303source kernel/Kconfig.hz 1304 1305config KEXEC 1306 bool "kexec system call" 1307 depends on X86_BIOS_REBOOT 1308 help 1309 kexec is a system call that implements the ability to shutdown your 1310 current kernel, and to start another kernel. It is like a reboot 1311 but it is independent of the system firmware. And like a reboot 1312 you can start any kernel with it, not just Linux. 1313 1314 The name comes from the similarity to the exec system call. 1315 1316 It is an ongoing process to be certain the hardware in a machine 1317 is properly shutdown, so do not be surprised if this code does not 1318 initially work for you. It may help to enable device hotplugging 1319 support. As of this writing the exact hardware interface is 1320 strongly in flux, so no good recommendation can be made. 1321 1322config CRASH_DUMP 1323 bool "kernel crash dumps" 1324 depends on X86_64 || (X86_32 && HIGHMEM) 1325 help 1326 Generate crash dump after being started by kexec. 1327 This should be normally only set in special crash dump kernels 1328 which are loaded in the main kernel with kexec-tools into 1329 a specially reserved region and then later executed after 1330 a crash by kdump/kexec. The crash dump kernel must be compiled 1331 to a memory address not used by the main kernel or BIOS using 1332 PHYSICAL_START, or it must be built as a relocatable image 1333 (CONFIG_RELOCATABLE=y). 1334 For more details see Documentation/kdump/kdump.txt 1335 1336config KEXEC_JUMP 1337 bool "kexec jump (EXPERIMENTAL)" 1338 depends on EXPERIMENTAL 1339 depends on KEXEC && HIBERNATION && X86_32 1340 help 1341 Jump between original kernel and kexeced kernel and invoke 1342 code in physical address mode via KEXEC 1343 1344config PHYSICAL_START 1345 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1346 default "0x1000000" if X86_NUMAQ 1347 default "0x200000" if X86_64 1348 default "0x100000" 1349 help 1350 This gives the physical address where the kernel is loaded. 1351 1352 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1353 bzImage will decompress itself to above physical address and 1354 run from there. Otherwise, bzImage will run from the address where 1355 it has been loaded by the boot loader and will ignore above physical 1356 address. 1357 1358 In normal kdump cases one does not have to set/change this option 1359 as now bzImage can be compiled as a completely relocatable image 1360 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1361 address. This option is mainly useful for the folks who don't want 1362 to use a bzImage for capturing the crash dump and want to use a 1363 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1364 to be specifically compiled to run from a specific memory area 1365 (normally a reserved region) and this option comes handy. 1366 1367 So if you are using bzImage for capturing the crash dump, leave 1368 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. 1369 Otherwise if you plan to use vmlinux for capturing the crash dump 1370 change this value to start of the reserved region (Typically 16MB 1371 0x1000000). In other words, it can be set based on the "X" value as 1372 specified in the "crashkernel=YM@XM" command line boot parameter 1373 passed to the panic-ed kernel. Typically this parameter is set as 1374 crashkernel=64M@16M. Please take a look at 1375 Documentation/kdump/kdump.txt for more details about crash dumps. 1376 1377 Usage of bzImage for capturing the crash dump is recommended as 1378 one does not have to build two kernels. Same kernel can be used 1379 as production kernel and capture kernel. Above option should have 1380 gone away after relocatable bzImage support is introduced. But it 1381 is present because there are users out there who continue to use 1382 vmlinux for dump capture. This option should go away down the 1383 line. 1384 1385 Don't change this unless you know what you are doing. 1386 1387config RELOCATABLE 1388 bool "Build a relocatable kernel (EXPERIMENTAL)" 1389 depends on EXPERIMENTAL 1390 help 1391 This builds a kernel image that retains relocation information 1392 so it can be loaded someplace besides the default 1MB. 1393 The relocations tend to make the kernel binary about 10% larger, 1394 but are discarded at runtime. 1395 1396 One use is for the kexec on panic case where the recovery kernel 1397 must live at a different physical address than the primary 1398 kernel. 1399 1400 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1401 it has been loaded at and the compile time physical address 1402 (CONFIG_PHYSICAL_START) is ignored. 1403 1404config PHYSICAL_ALIGN 1405 hex 1406 prompt "Alignment value to which kernel should be aligned" if X86_32 1407 default "0x100000" if X86_32 1408 default "0x200000" if X86_64 1409 range 0x2000 0x400000 1410 help 1411 This value puts the alignment restrictions on physical address 1412 where kernel is loaded and run from. Kernel is compiled for an 1413 address which meets above alignment restriction. 1414 1415 If bootloader loads the kernel at a non-aligned address and 1416 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1417 address aligned to above value and run from there. 1418 1419 If bootloader loads the kernel at a non-aligned address and 1420 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1421 load address and decompress itself to the address it has been 1422 compiled for and run from there. The address for which kernel is 1423 compiled already meets above alignment restrictions. Hence the 1424 end result is that kernel runs from a physical address meeting 1425 above alignment restrictions. 1426 1427 Don't change this unless you know what you are doing. 1428 1429config HOTPLUG_CPU 1430 bool "Support for hot-pluggable CPUs" 1431 depends on SMP && HOTPLUG && !X86_VOYAGER 1432 ---help--- 1433 Say Y here to allow turning CPUs off and on. CPUs can be 1434 controlled through /sys/devices/system/cpu. 1435 ( Note: power management support will enable this option 1436 automatically on SMP systems. ) 1437 Say N if you want to disable CPU hotplug. 1438 1439config COMPAT_VDSO 1440 def_bool y 1441 prompt "Compat VDSO support" 1442 depends on X86_32 || IA32_EMULATION 1443 help 1444 Map the 32-bit VDSO to the predictable old-style address too. 1445 ---help--- 1446 Say N here if you are running a sufficiently recent glibc 1447 version (2.3.3 or later), to remove the high-mapped 1448 VDSO mapping and to exclusively use the randomized VDSO. 1449 1450 If unsure, say Y. 1451 1452config CMDLINE_BOOL 1453 bool "Built-in kernel command line" 1454 default n 1455 help 1456 Allow for specifying boot arguments to the kernel at 1457 build time. On some systems (e.g. embedded ones), it is 1458 necessary or convenient to provide some or all of the 1459 kernel boot arguments with the kernel itself (that is, 1460 to not rely on the boot loader to provide them.) 1461 1462 To compile command line arguments into the kernel, 1463 set this option to 'Y', then fill in the 1464 the boot arguments in CONFIG_CMDLINE. 1465 1466 Systems with fully functional boot loaders (i.e. non-embedded) 1467 should leave this option set to 'N'. 1468 1469config CMDLINE 1470 string "Built-in kernel command string" 1471 depends on CMDLINE_BOOL 1472 default "" 1473 help 1474 Enter arguments here that should be compiled into the kernel 1475 image and used at boot time. If the boot loader provides a 1476 command line at boot time, it is appended to this string to 1477 form the full kernel command line, when the system boots. 1478 1479 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1480 change this behavior. 1481 1482 In most cases, the command line (whether built-in or provided 1483 by the boot loader) should specify the device for the root 1484 file system. 1485 1486config CMDLINE_OVERRIDE 1487 bool "Built-in command line overrides boot loader arguments" 1488 default n 1489 depends on CMDLINE_BOOL 1490 help 1491 Set this option to 'Y' to have the kernel ignore the boot loader 1492 command line, and use ONLY the built-in command line. 1493 1494 This is used to work around broken boot loaders. This should 1495 be set to 'N' under normal conditions. 1496 1497endmenu 1498 1499config ARCH_ENABLE_MEMORY_HOTPLUG 1500 def_bool y 1501 depends on X86_64 || (X86_32 && HIGHMEM) 1502 1503config HAVE_ARCH_EARLY_PFN_TO_NID 1504 def_bool X86_64 1505 depends on NUMA 1506 1507menu "Power management options" 1508 depends on !X86_VOYAGER 1509 1510config ARCH_HIBERNATION_HEADER 1511 def_bool y 1512 depends on X86_64 && HIBERNATION 1513 1514source "kernel/power/Kconfig" 1515 1516source "drivers/acpi/Kconfig" 1517 1518config X86_APM_BOOT 1519 bool 1520 default y 1521 depends on APM || APM_MODULE 1522 1523menuconfig APM 1524 tristate "APM (Advanced Power Management) BIOS support" 1525 depends on X86_32 && PM_SLEEP 1526 ---help--- 1527 APM is a BIOS specification for saving power using several different 1528 techniques. This is mostly useful for battery powered laptops with 1529 APM compliant BIOSes. If you say Y here, the system time will be 1530 reset after a RESUME operation, the /proc/apm device will provide 1531 battery status information, and user-space programs will receive 1532 notification of APM "events" (e.g. battery status change). 1533 1534 If you select "Y" here, you can disable actual use of the APM 1535 BIOS by passing the "apm=off" option to the kernel at boot time. 1536 1537 Note that the APM support is almost completely disabled for 1538 machines with more than one CPU. 1539 1540 In order to use APM, you will need supporting software. For location 1541 and more information, read <file:Documentation/power/pm.txt> and the 1542 Battery Powered Linux mini-HOWTO, available from 1543 <http://www.tldp.org/docs.html#howto>. 1544 1545 This driver does not spin down disk drives (see the hdparm(8) 1546 manpage ("man 8 hdparm") for that), and it doesn't turn off 1547 VESA-compliant "green" monitors. 1548 1549 This driver does not support the TI 4000M TravelMate and the ACER 1550 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1551 desktop machines also don't have compliant BIOSes, and this driver 1552 may cause those machines to panic during the boot phase. 1553 1554 Generally, if you don't have a battery in your machine, there isn't 1555 much point in using this driver and you should say N. If you get 1556 random kernel OOPSes or reboots that don't seem to be related to 1557 anything, try disabling/enabling this option (or disabling/enabling 1558 APM in your BIOS). 1559 1560 Some other things you should try when experiencing seemingly random, 1561 "weird" problems: 1562 1563 1) make sure that you have enough swap space and that it is 1564 enabled. 1565 2) pass the "no-hlt" option to the kernel 1566 3) switch on floating point emulation in the kernel and pass 1567 the "no387" option to the kernel 1568 4) pass the "floppy=nodma" option to the kernel 1569 5) pass the "mem=4M" option to the kernel (thereby disabling 1570 all but the first 4 MB of RAM) 1571 6) make sure that the CPU is not over clocked. 1572 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1573 8) disable the cache from your BIOS settings 1574 9) install a fan for the video card or exchange video RAM 1575 10) install a better fan for the CPU 1576 11) exchange RAM chips 1577 12) exchange the motherboard. 1578 1579 To compile this driver as a module, choose M here: the 1580 module will be called apm. 1581 1582if APM 1583 1584config APM_IGNORE_USER_SUSPEND 1585 bool "Ignore USER SUSPEND" 1586 help 1587 This option will ignore USER SUSPEND requests. On machines with a 1588 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1589 series notebooks, it is necessary to say Y because of a BIOS bug. 1590 1591config APM_DO_ENABLE 1592 bool "Enable PM at boot time" 1593 ---help--- 1594 Enable APM features at boot time. From page 36 of the APM BIOS 1595 specification: "When disabled, the APM BIOS does not automatically 1596 power manage devices, enter the Standby State, enter the Suspend 1597 State, or take power saving steps in response to CPU Idle calls." 1598 This driver will make CPU Idle calls when Linux is idle (unless this 1599 feature is turned off -- see "Do CPU IDLE calls", below). This 1600 should always save battery power, but more complicated APM features 1601 will be dependent on your BIOS implementation. You may need to turn 1602 this option off if your computer hangs at boot time when using APM 1603 support, or if it beeps continuously instead of suspending. Turn 1604 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1605 T400CDT. This is off by default since most machines do fine without 1606 this feature. 1607 1608config APM_CPU_IDLE 1609 bool "Make CPU Idle calls when idle" 1610 help 1611 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1612 On some machines, this can activate improved power savings, such as 1613 a slowed CPU clock rate, when the machine is idle. These idle calls 1614 are made after the idle loop has run for some length of time (e.g., 1615 333 mS). On some machines, this will cause a hang at boot time or 1616 whenever the CPU becomes idle. (On machines with more than one CPU, 1617 this option does nothing.) 1618 1619config APM_DISPLAY_BLANK 1620 bool "Enable console blanking using APM" 1621 help 1622 Enable console blanking using the APM. Some laptops can use this to 1623 turn off the LCD backlight when the screen blanker of the Linux 1624 virtual console blanks the screen. Note that this is only used by 1625 the virtual console screen blanker, and won't turn off the backlight 1626 when using the X Window system. This also doesn't have anything to 1627 do with your VESA-compliant power-saving monitor. Further, this 1628 option doesn't work for all laptops -- it might not turn off your 1629 backlight at all, or it might print a lot of errors to the console, 1630 especially if you are using gpm. 1631 1632config APM_ALLOW_INTS 1633 bool "Allow interrupts during APM BIOS calls" 1634 help 1635 Normally we disable external interrupts while we are making calls to 1636 the APM BIOS as a measure to lessen the effects of a badly behaving 1637 BIOS implementation. The BIOS should reenable interrupts if it 1638 needs to. Unfortunately, some BIOSes do not -- especially those in 1639 many of the newer IBM Thinkpads. If you experience hangs when you 1640 suspend, try setting this to Y. Otherwise, say N. 1641 1642config APM_REAL_MODE_POWER_OFF 1643 bool "Use real mode APM BIOS call to power off" 1644 help 1645 Use real mode APM BIOS calls to switch off the computer. This is 1646 a work-around for a number of buggy BIOSes. Switch this option on if 1647 your computer crashes instead of powering off properly. 1648 1649endif # APM 1650 1651source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1652 1653source "drivers/cpuidle/Kconfig" 1654 1655endmenu 1656 1657 1658menu "Bus options (PCI etc.)" 1659 1660config PCI 1661 bool "PCI support" 1662 default y 1663 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1664 help 1665 Find out whether you have a PCI motherboard. PCI is the name of a 1666 bus system, i.e. the way the CPU talks to the other stuff inside 1667 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1668 VESA. If you have PCI, say Y, otherwise N. 1669 1670choice 1671 prompt "PCI access mode" 1672 depends on X86_32 && PCI 1673 default PCI_GOANY 1674 ---help--- 1675 On PCI systems, the BIOS can be used to detect the PCI devices and 1676 determine their configuration. However, some old PCI motherboards 1677 have BIOS bugs and may crash if this is done. Also, some embedded 1678 PCI-based systems don't have any BIOS at all. Linux can also try to 1679 detect the PCI hardware directly without using the BIOS. 1680 1681 With this option, you can specify how Linux should detect the 1682 PCI devices. If you choose "BIOS", the BIOS will be used, 1683 if you choose "Direct", the BIOS won't be used, and if you 1684 choose "MMConfig", then PCI Express MMCONFIG will be used. 1685 If you choose "Any", the kernel will try MMCONFIG, then the 1686 direct access method and falls back to the BIOS if that doesn't 1687 work. If unsure, go with the default, which is "Any". 1688 1689config PCI_GOBIOS 1690 bool "BIOS" 1691 1692config PCI_GOMMCONFIG 1693 bool "MMConfig" 1694 1695config PCI_GODIRECT 1696 bool "Direct" 1697 1698config PCI_GOOLPC 1699 bool "OLPC" 1700 depends on OLPC 1701 1702config PCI_GOANY 1703 bool "Any" 1704 1705endchoice 1706 1707config PCI_BIOS 1708 def_bool y 1709 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1710 1711# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1712config PCI_DIRECT 1713 def_bool y 1714 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1715 1716config PCI_MMCONFIG 1717 def_bool y 1718 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1719 1720config PCI_OLPC 1721 def_bool y 1722 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1723 1724config PCI_DOMAINS 1725 def_bool y 1726 depends on PCI 1727 1728config PCI_MMCONFIG 1729 bool "Support mmconfig PCI config space access" 1730 depends on X86_64 && PCI && ACPI 1731 1732config DMAR 1733 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1734 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL 1735 help 1736 DMA remapping (DMAR) devices support enables independent address 1737 translations for Direct Memory Access (DMA) from devices. 1738 These DMA remapping devices are reported via ACPI tables 1739 and include PCI device scope covered by these DMA 1740 remapping devices. 1741 1742config DMAR_GFX_WA 1743 def_bool y 1744 prompt "Support for Graphics workaround" 1745 depends on DMAR 1746 help 1747 Current Graphics drivers tend to use physical address 1748 for DMA and avoid using DMA APIs. Setting this config 1749 option permits the IOMMU driver to set a unity map for 1750 all the OS-visible memory. Hence the driver can continue 1751 to use physical addresses for DMA. 1752 1753config DMAR_FLOPPY_WA 1754 def_bool y 1755 depends on DMAR 1756 help 1757 Floppy disk drivers are know to bypass DMA API calls 1758 thereby failing to work when IOMMU is enabled. This 1759 workaround will setup a 1:1 mapping for the first 1760 16M to make floppy (an ISA device) work. 1761 1762config INTR_REMAP 1763 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1764 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1765 help 1766 Supports Interrupt remapping for IO-APIC and MSI devices. 1767 To use x2apic mode in the CPU's which support x2APIC enhancements or 1768 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1769 1770source "drivers/pci/pcie/Kconfig" 1771 1772source "drivers/pci/Kconfig" 1773 1774# x86_64 have no ISA slots, but do have ISA-style DMA. 1775config ISA_DMA_API 1776 def_bool y 1777 1778if X86_32 1779 1780config ISA 1781 bool "ISA support" 1782 depends on !X86_VOYAGER 1783 help 1784 Find out whether you have ISA slots on your motherboard. ISA is the 1785 name of a bus system, i.e. the way the CPU talks to the other stuff 1786 inside your box. Other bus systems are PCI, EISA, MicroChannel 1787 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1788 newer boards don't support it. If you have ISA, say Y, otherwise N. 1789 1790config EISA 1791 bool "EISA support" 1792 depends on ISA 1793 ---help--- 1794 The Extended Industry Standard Architecture (EISA) bus was 1795 developed as an open alternative to the IBM MicroChannel bus. 1796 1797 The EISA bus provided some of the features of the IBM MicroChannel 1798 bus while maintaining backward compatibility with cards made for 1799 the older ISA bus. The EISA bus saw limited use between 1988 and 1800 1995 when it was made obsolete by the PCI bus. 1801 1802 Say Y here if you are building a kernel for an EISA-based machine. 1803 1804 Otherwise, say N. 1805 1806source "drivers/eisa/Kconfig" 1807 1808config MCA 1809 bool "MCA support" if !X86_VOYAGER 1810 default y if X86_VOYAGER 1811 help 1812 MicroChannel Architecture is found in some IBM PS/2 machines and 1813 laptops. It is a bus system similar to PCI or ISA. See 1814 <file:Documentation/mca.txt> (and especially the web page given 1815 there) before attempting to build an MCA bus kernel. 1816 1817source "drivers/mca/Kconfig" 1818 1819config SCx200 1820 tristate "NatSemi SCx200 support" 1821 depends on !X86_VOYAGER 1822 help 1823 This provides basic support for National Semiconductor's 1824 (now AMD's) Geode processors. The driver probes for the 1825 PCI-IDs of several on-chip devices, so its a good dependency 1826 for other scx200_* drivers. 1827 1828 If compiled as a module, the driver is named scx200. 1829 1830config SCx200HR_TIMER 1831 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 1832 depends on SCx200 && GENERIC_TIME 1833 default y 1834 help 1835 This driver provides a clocksource built upon the on-chip 1836 27MHz high-resolution timer. Its also a workaround for 1837 NSC Geode SC-1100's buggy TSC, which loses time when the 1838 processor goes idle (as is done by the scheduler). The 1839 other workaround is idle=poll boot option. 1840 1841config GEODE_MFGPT_TIMER 1842 def_bool y 1843 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 1844 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 1845 help 1846 This driver provides a clock event source based on the MFGPT 1847 timer(s) in the CS5535 and CS5536 companion chip for the geode. 1848 MFGPTs have a better resolution and max interval than the 1849 generic PIT, and are suitable for use as high-res timers. 1850 1851config OLPC 1852 bool "One Laptop Per Child support" 1853 default n 1854 help 1855 Add support for detecting the unique features of the OLPC 1856 XO hardware. 1857 1858endif # X86_32 1859 1860config K8_NB 1861 def_bool y 1862 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 1863 1864source "drivers/pcmcia/Kconfig" 1865 1866source "drivers/pci/hotplug/Kconfig" 1867 1868endmenu 1869 1870 1871menu "Executable file formats / Emulations" 1872 1873source "fs/Kconfig.binfmt" 1874 1875config IA32_EMULATION 1876 bool "IA32 Emulation" 1877 depends on X86_64 1878 select COMPAT_BINFMT_ELF 1879 help 1880 Include code to run 32-bit programs under a 64-bit kernel. You should 1881 likely turn this on, unless you're 100% sure that you don't have any 1882 32-bit programs left. 1883 1884config IA32_AOUT 1885 tristate "IA32 a.out support" 1886 depends on IA32_EMULATION 1887 help 1888 Support old a.out binaries in the 32bit emulation. 1889 1890config COMPAT 1891 def_bool y 1892 depends on IA32_EMULATION 1893 1894config COMPAT_FOR_U64_ALIGNMENT 1895 def_bool COMPAT 1896 depends on X86_64 1897 1898config SYSVIPC_COMPAT 1899 def_bool y 1900 depends on COMPAT && SYSVIPC 1901 1902endmenu 1903 1904 1905source "net/Kconfig" 1906 1907source "drivers/Kconfig" 1908 1909source "drivers/firmware/Kconfig" 1910 1911source "fs/Kconfig" 1912 1913source "arch/x86/Kconfig.debug" 1914 1915source "security/Kconfig" 1916 1917source "crypto/Kconfig" 1918 1919source "arch/x86/kvm/Kconfig" 1920 1921source "lib/Kconfig" 1922