1# SPDX-License-Identifier: GPL-2.0 2# Select 32 or 64 bit 3config 64BIT 4 bool "64-bit kernel" if "$(ARCH)" = "x86" 5 default "$(ARCH)" != "i386" 6 ---help--- 7 Say yes to build a 64-bit kernel - formerly known as x86_64 8 Say no to build a 32-bit kernel - formerly known as i386 9 10config X86_32 11 def_bool y 12 depends on !64BIT 13 # Options that are inherently 32-bit kernel only: 14 select ARCH_WANT_IPC_PARSE_VERSION 15 select CLKSRC_I8253 16 select CLONE_BACKWARDS 17 select HAVE_AOUT 18 select HAVE_GENERIC_DMA_COHERENT 19 select MODULES_USE_ELF_REL 20 select OLD_SIGACTION 21 22config X86_64 23 def_bool y 24 depends on 64BIT 25 # Options that are inherently 64-bit kernel only: 26 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA 27 select ARCH_SUPPORTS_INT128 28 select ARCH_USE_CMPXCHG_LOCKREF 29 select HAVE_ARCH_SOFT_DIRTY 30 select MODULES_USE_ELF_RELA 31 select NEED_DMA_MAP_STATE 32 select SWIOTLB 33 select X86_DEV_DMA_OPS 34 select ARCH_HAS_SYSCALL_WRAPPER 35 36# 37# Arch settings 38# 39# ( Note that options that are marked 'if X86_64' could in principle be 40# ported to 32-bit as well. ) 41# 42config X86 43 def_bool y 44 # 45 # Note: keep this list sorted alphabetically 46 # 47 select ACPI_LEGACY_TABLES_LOOKUP if ACPI 48 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 49 select ANON_INODES 50 select ARCH_CLOCKSOURCE_DATA 51 select ARCH_CLOCKSOURCE_INIT 52 select ARCH_DISCARD_MEMBLOCK 53 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 54 select ARCH_HAS_DEBUG_VIRTUAL 55 select ARCH_HAS_DEVMEM_IS_ALLOWED 56 select ARCH_HAS_ELF_RANDOMIZE 57 select ARCH_HAS_FAST_MULTIPLIER 58 select ARCH_HAS_FILTER_PGPROT 59 select ARCH_HAS_FORTIFY_SOURCE 60 select ARCH_HAS_GCOV_PROFILE_ALL 61 select ARCH_HAS_KCOV if X86_64 62 select ARCH_HAS_MEMBARRIER_SYNC_CORE 63 select ARCH_HAS_PMEM_API if X86_64 64 select ARCH_HAS_PTE_SPECIAL 65 select ARCH_HAS_REFCOUNT 66 select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 67 select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE 68 select ARCH_HAS_SET_MEMORY 69 select ARCH_HAS_SG_CHAIN 70 select ARCH_HAS_STRICT_KERNEL_RWX 71 select ARCH_HAS_STRICT_MODULE_RWX 72 select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 73 select ARCH_HAS_UBSAN_SANITIZE_ALL 74 select ARCH_HAS_ZONE_DEVICE if X86_64 75 select ARCH_HAVE_NMI_SAFE_CMPXCHG 76 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 77 select ARCH_MIGHT_HAVE_PC_PARPORT 78 select ARCH_MIGHT_HAVE_PC_SERIO 79 select ARCH_SUPPORTS_ACPI 80 select ARCH_SUPPORTS_ATOMIC_RMW 81 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 82 select ARCH_USE_BUILTIN_BSWAP 83 select ARCH_USE_QUEUED_RWLOCKS 84 select ARCH_USE_QUEUED_SPINLOCKS 85 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 86 select ARCH_WANTS_DYNAMIC_TASK_STRUCT 87 select ARCH_WANTS_THP_SWAP if X86_64 88 select BUILDTIME_EXTABLE_SORT 89 select CLKEVT_I8253 90 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 91 select CLOCKSOURCE_WATCHDOG 92 select DCACHE_WORD_ACCESS 93 select DMA_DIRECT_OPS 94 select EDAC_ATOMIC_SCRUB 95 select EDAC_SUPPORT 96 select GENERIC_CLOCKEVENTS 97 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 98 select GENERIC_CLOCKEVENTS_MIN_ADJUST 99 select GENERIC_CMOS_UPDATE 100 select GENERIC_CPU_AUTOPROBE 101 select GENERIC_CPU_VULNERABILITIES 102 select GENERIC_EARLY_IOREMAP 103 select GENERIC_FIND_FIRST_BIT 104 select GENERIC_IOMAP 105 select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 106 select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 107 select GENERIC_IRQ_MIGRATION if SMP 108 select GENERIC_IRQ_PROBE 109 select GENERIC_IRQ_RESERVATION_MODE 110 select GENERIC_IRQ_SHOW 111 select GENERIC_PENDING_IRQ if SMP 112 select GENERIC_SMP_IDLE_THREAD 113 select GENERIC_STRNCPY_FROM_USER 114 select GENERIC_STRNLEN_USER 115 select GENERIC_TIME_VSYSCALL 116 select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 117 select HAVE_ACPI_APEI if ACPI 118 select HAVE_ACPI_APEI_NMI if ACPI 119 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 120 select HAVE_ARCH_AUDITSYSCALL 121 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 122 select HAVE_ARCH_JUMP_LABEL 123 select HAVE_ARCH_JUMP_LABEL_RELATIVE 124 select HAVE_ARCH_KASAN if X86_64 125 select HAVE_ARCH_KGDB 126 select HAVE_ARCH_MMAP_RND_BITS if MMU 127 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 128 select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 129 select HAVE_ARCH_PREL32_RELOCATIONS 130 select HAVE_ARCH_SECCOMP_FILTER 131 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 132 select HAVE_ARCH_STACKLEAK 133 select HAVE_ARCH_TRACEHOOK 134 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 135 select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 136 select HAVE_ARCH_VMAP_STACK if X86_64 137 select HAVE_ARCH_WITHIN_STACK_FRAMES 138 select HAVE_CMPXCHG_DOUBLE 139 select HAVE_CMPXCHG_LOCAL 140 select HAVE_CONTEXT_TRACKING if X86_64 141 select HAVE_COPY_THREAD_TLS 142 select HAVE_C_RECORDMCOUNT 143 select HAVE_DEBUG_KMEMLEAK 144 select HAVE_DEBUG_STACKOVERFLOW 145 select HAVE_DMA_CONTIGUOUS 146 select HAVE_DYNAMIC_FTRACE 147 select HAVE_DYNAMIC_FTRACE_WITH_REGS 148 select HAVE_EBPF_JIT 149 select HAVE_EFFICIENT_UNALIGNED_ACCESS 150 select HAVE_EXIT_THREAD 151 select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 152 select HAVE_FTRACE_MCOUNT_RECORD 153 select HAVE_FUNCTION_GRAPH_TRACER 154 select HAVE_FUNCTION_TRACER 155 select HAVE_GCC_PLUGINS 156 select HAVE_HW_BREAKPOINT 157 select HAVE_IDE 158 select HAVE_IOREMAP_PROT 159 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 160 select HAVE_IRQ_TIME_ACCOUNTING 161 select HAVE_KERNEL_BZIP2 162 select HAVE_KERNEL_GZIP 163 select HAVE_KERNEL_LZ4 164 select HAVE_KERNEL_LZMA 165 select HAVE_KERNEL_LZO 166 select HAVE_KERNEL_XZ 167 select HAVE_KPROBES 168 select HAVE_KPROBES_ON_FTRACE 169 select HAVE_FUNCTION_ERROR_INJECTION 170 select HAVE_KRETPROBES 171 select HAVE_KVM 172 select HAVE_LIVEPATCH if X86_64 173 select HAVE_MEMBLOCK_NODE_MAP 174 select HAVE_MIXED_BREAKPOINTS_REGS 175 select HAVE_MOD_ARCH_SPECIFIC 176 select HAVE_NMI 177 select HAVE_OPROFILE 178 select HAVE_OPTPROBES 179 select HAVE_PCSPKR_PLATFORM 180 select HAVE_PERF_EVENTS 181 select HAVE_PERF_EVENTS_NMI 182 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 183 select HAVE_PERF_REGS 184 select HAVE_PERF_USER_STACK_DUMP 185 select HAVE_RCU_TABLE_FREE if PARAVIRT 186 select HAVE_RCU_TABLE_INVALIDATE if HAVE_RCU_TABLE_FREE 187 select HAVE_REGS_AND_STACK_ACCESS_API 188 select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION 189 select HAVE_FUNCTION_ARG_ACCESS_API 190 select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR 191 select HAVE_STACK_VALIDATION if X86_64 192 select HAVE_RSEQ 193 select HAVE_SYSCALL_TRACEPOINTS 194 select HAVE_UNSTABLE_SCHED_CLOCK 195 select HAVE_USER_RETURN_NOTIFIER 196 select HOTPLUG_SMT if SMP 197 select IRQ_FORCED_THREADING 198 select NEED_SG_DMA_LENGTH 199 select PCI_LOCKLESS_CONFIG 200 select PERF_EVENTS 201 select RTC_LIB 202 select RTC_MC146818_LIB 203 select SPARSE_IRQ 204 select SRCU 205 select SYSCTL_EXCEPTION_TRACE 206 select THREAD_INFO_IN_TASK 207 select USER_STACKTRACE_SUPPORT 208 select VIRT_TO_BUS 209 select X86_FEATURE_NAMES if PROC_FS 210 211config INSTRUCTION_DECODER 212 def_bool y 213 depends on KPROBES || PERF_EVENTS || UPROBES 214 215config OUTPUT_FORMAT 216 string 217 default "elf32-i386" if X86_32 218 default "elf64-x86-64" if X86_64 219 220config ARCH_DEFCONFIG 221 string 222 default "arch/x86/configs/i386_defconfig" if X86_32 223 default "arch/x86/configs/x86_64_defconfig" if X86_64 224 225config LOCKDEP_SUPPORT 226 def_bool y 227 228config STACKTRACE_SUPPORT 229 def_bool y 230 231config MMU 232 def_bool y 233 234config ARCH_MMAP_RND_BITS_MIN 235 default 28 if 64BIT 236 default 8 237 238config ARCH_MMAP_RND_BITS_MAX 239 default 32 if 64BIT 240 default 16 241 242config ARCH_MMAP_RND_COMPAT_BITS_MIN 243 default 8 244 245config ARCH_MMAP_RND_COMPAT_BITS_MAX 246 default 16 247 248config SBUS 249 bool 250 251config GENERIC_ISA_DMA 252 def_bool y 253 depends on ISA_DMA_API 254 255config GENERIC_BUG 256 def_bool y 257 depends on BUG 258 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 259 260config GENERIC_BUG_RELATIVE_POINTERS 261 bool 262 263config GENERIC_HWEIGHT 264 def_bool y 265 266config ARCH_MAY_HAVE_PC_FDC 267 def_bool y 268 depends on ISA_DMA_API 269 270config RWSEM_XCHGADD_ALGORITHM 271 def_bool y 272 273config GENERIC_CALIBRATE_DELAY 274 def_bool y 275 276config ARCH_HAS_CPU_RELAX 277 def_bool y 278 279config ARCH_HAS_CACHE_LINE_SIZE 280 def_bool y 281 282config ARCH_HAS_FILTER_PGPROT 283 def_bool y 284 285config HAVE_SETUP_PER_CPU_AREA 286 def_bool y 287 288config NEED_PER_CPU_EMBED_FIRST_CHUNK 289 def_bool y 290 291config NEED_PER_CPU_PAGE_FIRST_CHUNK 292 def_bool y 293 294config ARCH_HIBERNATION_POSSIBLE 295 def_bool y 296 297config ARCH_SUSPEND_POSSIBLE 298 def_bool y 299 300config ARCH_WANT_HUGE_PMD_SHARE 301 def_bool y 302 303config ARCH_WANT_GENERAL_HUGETLB 304 def_bool y 305 306config ZONE_DMA32 307 def_bool y if X86_64 308 309config AUDIT_ARCH 310 def_bool y if X86_64 311 312config ARCH_SUPPORTS_OPTIMIZED_INLINING 313 def_bool y 314 315config ARCH_SUPPORTS_DEBUG_PAGEALLOC 316 def_bool y 317 318config KASAN_SHADOW_OFFSET 319 hex 320 depends on KASAN 321 default 0xdffffc0000000000 322 323config HAVE_INTEL_TXT 324 def_bool y 325 depends on INTEL_IOMMU && ACPI 326 327config X86_32_SMP 328 def_bool y 329 depends on X86_32 && SMP 330 331config X86_64_SMP 332 def_bool y 333 depends on X86_64 && SMP 334 335config X86_32_LAZY_GS 336 def_bool y 337 depends on X86_32 && !STACKPROTECTOR 338 339config ARCH_SUPPORTS_UPROBES 340 def_bool y 341 342config FIX_EARLYCON_MEM 343 def_bool y 344 345config DYNAMIC_PHYSICAL_MASK 346 bool 347 348config PGTABLE_LEVELS 349 int 350 default 5 if X86_5LEVEL 351 default 4 if X86_64 352 default 3 if X86_PAE 353 default 2 354 355config CC_HAS_SANE_STACKPROTECTOR 356 bool 357 default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT 358 default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC)) 359 help 360 We have to make sure stack protector is unconditionally disabled if 361 the compiler produces broken code. 362 363menu "Processor type and features" 364 365config ZONE_DMA 366 bool "DMA memory allocation support" if EXPERT 367 default y 368 help 369 DMA memory allocation support allows devices with less than 32-bit 370 addressing to allocate within the first 16MB of address space. 371 Disable if no such devices will be used. 372 373 If unsure, say Y. 374 375config SMP 376 bool "Symmetric multi-processing support" 377 ---help--- 378 This enables support for systems with more than one CPU. If you have 379 a system with only one CPU, say N. If you have a system with more 380 than one CPU, say Y. 381 382 If you say N here, the kernel will run on uni- and multiprocessor 383 machines, but will use only one CPU of a multiprocessor machine. If 384 you say Y here, the kernel will run on many, but not all, 385 uniprocessor machines. On a uniprocessor machine, the kernel 386 will run faster if you say N here. 387 388 Note that if you say Y here and choose architecture "586" or 389 "Pentium" under "Processor family", the kernel will not work on 486 390 architectures. Similarly, multiprocessor kernels for the "PPro" 391 architecture may not work on all Pentium based boards. 392 393 People using multiprocessor machines who say Y here should also say 394 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 395 Management" code will be disabled if you say Y here. 396 397 See also <file:Documentation/x86/i386/IO-APIC.txt>, 398 <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 399 <http://www.tldp.org/docs.html#howto>. 400 401 If you don't know what to do here, say N. 402 403config X86_FEATURE_NAMES 404 bool "Processor feature human-readable names" if EMBEDDED 405 default y 406 ---help--- 407 This option compiles in a table of x86 feature bits and corresponding 408 names. This is required to support /proc/cpuinfo and a few kernel 409 messages. You can disable this to save space, at the expense of 410 making those few kernel messages show numeric feature bits instead. 411 412 If in doubt, say Y. 413 414config X86_X2APIC 415 bool "Support x2apic" 416 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 417 ---help--- 418 This enables x2apic support on CPUs that have this feature. 419 420 This allows 32-bit apic IDs (so it can support very large systems), 421 and accesses the local apic via MSRs not via mmio. 422 423 If you don't know what to do here, say N. 424 425config X86_MPPARSE 426 bool "Enable MPS table" if ACPI || SFI 427 default y 428 depends on X86_LOCAL_APIC 429 ---help--- 430 For old smp systems that do not have proper acpi support. Newer systems 431 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 432 433config GOLDFISH 434 def_bool y 435 depends on X86_GOLDFISH 436 437config RETPOLINE 438 bool "Avoid speculative indirect branches in kernel" 439 default y 440 select STACK_VALIDATION if HAVE_STACK_VALIDATION 441 help 442 Compile kernel with the retpoline compiler options to guard against 443 kernel-to-user data leaks by avoiding speculative indirect 444 branches. Requires a compiler with -mindirect-branch=thunk-extern 445 support for full protection. The kernel may run slower. 446 447 Without compiler support, at least indirect branches in assembler 448 code are eliminated. Since this includes the syscall entry path, 449 it is not entirely pointless. 450 451config INTEL_RDT 452 bool "Intel Resource Director Technology support" 453 depends on X86 && CPU_SUP_INTEL 454 select KERNFS 455 help 456 Select to enable resource allocation and monitoring which are 457 sub-features of Intel Resource Director Technology(RDT). More 458 information about RDT can be found in the Intel x86 459 Architecture Software Developer Manual. 460 461 Say N if unsure. 462 463if X86_32 464config X86_BIGSMP 465 bool "Support for big SMP systems with more than 8 CPUs" 466 depends on SMP 467 ---help--- 468 This option is needed for the systems that have more than 8 CPUs 469 470config X86_EXTENDED_PLATFORM 471 bool "Support for extended (non-PC) x86 platforms" 472 default y 473 ---help--- 474 If you disable this option then the kernel will only support 475 standard PC platforms. (which covers the vast majority of 476 systems out there.) 477 478 If you enable this option then you'll be able to select support 479 for the following (non-PC) 32 bit x86 platforms: 480 Goldfish (Android emulator) 481 AMD Elan 482 RDC R-321x SoC 483 SGI 320/540 (Visual Workstation) 484 STA2X11-based (e.g. Northville) 485 Moorestown MID devices 486 487 If you have one of these systems, or if you want to build a 488 generic distribution kernel, say Y here - otherwise say N. 489endif 490 491if X86_64 492config X86_EXTENDED_PLATFORM 493 bool "Support for extended (non-PC) x86 platforms" 494 default y 495 ---help--- 496 If you disable this option then the kernel will only support 497 standard PC platforms. (which covers the vast majority of 498 systems out there.) 499 500 If you enable this option then you'll be able to select support 501 for the following (non-PC) 64 bit x86 platforms: 502 Numascale NumaChip 503 ScaleMP vSMP 504 SGI Ultraviolet 505 506 If you have one of these systems, or if you want to build a 507 generic distribution kernel, say Y here - otherwise say N. 508endif 509# This is an alphabetically sorted list of 64 bit extended platforms 510# Please maintain the alphabetic order if and when there are additions 511config X86_NUMACHIP 512 bool "Numascale NumaChip" 513 depends on X86_64 514 depends on X86_EXTENDED_PLATFORM 515 depends on NUMA 516 depends on SMP 517 depends on X86_X2APIC 518 depends on PCI_MMCONFIG 519 ---help--- 520 Adds support for Numascale NumaChip large-SMP systems. Needed to 521 enable more than ~168 cores. 522 If you don't have one of these, you should say N here. 523 524config X86_VSMP 525 bool "ScaleMP vSMP" 526 select HYPERVISOR_GUEST 527 select PARAVIRT 528 select PARAVIRT_XXL 529 depends on X86_64 && PCI 530 depends on X86_EXTENDED_PLATFORM 531 depends on SMP 532 ---help--- 533 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 534 supposed to run on these EM64T-based machines. Only choose this option 535 if you have one of these machines. 536 537config X86_UV 538 bool "SGI Ultraviolet" 539 depends on X86_64 540 depends on X86_EXTENDED_PLATFORM 541 depends on NUMA 542 depends on EFI 543 depends on X86_X2APIC 544 depends on PCI 545 ---help--- 546 This option is needed in order to support SGI Ultraviolet systems. 547 If you don't have one of these, you should say N here. 548 549# Following is an alphabetically sorted list of 32 bit extended platforms 550# Please maintain the alphabetic order if and when there are additions 551 552config X86_GOLDFISH 553 bool "Goldfish (Virtual Platform)" 554 depends on X86_EXTENDED_PLATFORM 555 ---help--- 556 Enable support for the Goldfish virtual platform used primarily 557 for Android development. Unless you are building for the Android 558 Goldfish emulator say N here. 559 560config X86_INTEL_CE 561 bool "CE4100 TV platform" 562 depends on PCI 563 depends on PCI_GODIRECT 564 depends on X86_IO_APIC 565 depends on X86_32 566 depends on X86_EXTENDED_PLATFORM 567 select X86_REBOOTFIXUPS 568 select OF 569 select OF_EARLY_FLATTREE 570 ---help--- 571 Select for the Intel CE media processor (CE4100) SOC. 572 This option compiles in support for the CE4100 SOC for settop 573 boxes and media devices. 574 575config X86_INTEL_MID 576 bool "Intel MID platform support" 577 depends on X86_EXTENDED_PLATFORM 578 depends on X86_PLATFORM_DEVICES 579 depends on PCI 580 depends on X86_64 || (PCI_GOANY && X86_32) 581 depends on X86_IO_APIC 582 select SFI 583 select I2C 584 select DW_APB_TIMER 585 select APB_TIMER 586 select INTEL_SCU_IPC 587 select MFD_INTEL_MSIC 588 ---help--- 589 Select to build a kernel capable of supporting Intel MID (Mobile 590 Internet Device) platform systems which do not have the PCI legacy 591 interfaces. If you are building for a PC class system say N here. 592 593 Intel MID platforms are based on an Intel processor and chipset which 594 consume less power than most of the x86 derivatives. 595 596config X86_INTEL_QUARK 597 bool "Intel Quark platform support" 598 depends on X86_32 599 depends on X86_EXTENDED_PLATFORM 600 depends on X86_PLATFORM_DEVICES 601 depends on X86_TSC 602 depends on PCI 603 depends on PCI_GOANY 604 depends on X86_IO_APIC 605 select IOSF_MBI 606 select INTEL_IMR 607 select COMMON_CLK 608 ---help--- 609 Select to include support for Quark X1000 SoC. 610 Say Y here if you have a Quark based system such as the Arduino 611 compatible Intel Galileo. 612 613config X86_INTEL_LPSS 614 bool "Intel Low Power Subsystem Support" 615 depends on X86 && ACPI 616 select COMMON_CLK 617 select PINCTRL 618 select IOSF_MBI 619 ---help--- 620 Select to build support for Intel Low Power Subsystem such as 621 found on Intel Lynxpoint PCH. Selecting this option enables 622 things like clock tree (common clock framework) and pincontrol 623 which are needed by the LPSS peripheral drivers. 624 625config X86_AMD_PLATFORM_DEVICE 626 bool "AMD ACPI2Platform devices support" 627 depends on ACPI 628 select COMMON_CLK 629 select PINCTRL 630 ---help--- 631 Select to interpret AMD specific ACPI device to platform device 632 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 633 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 634 implemented under PINCTRL subsystem. 635 636config IOSF_MBI 637 tristate "Intel SoC IOSF Sideband support for SoC platforms" 638 depends on PCI 639 ---help--- 640 This option enables sideband register access support for Intel SoC 641 platforms. On these platforms the IOSF sideband is used in lieu of 642 MSR's for some register accesses, mostly but not limited to thermal 643 and power. Drivers may query the availability of this device to 644 determine if they need the sideband in order to work on these 645 platforms. The sideband is available on the following SoC products. 646 This list is not meant to be exclusive. 647 - BayTrail 648 - Braswell 649 - Quark 650 651 You should say Y if you are running a kernel on one of these SoC's. 652 653config IOSF_MBI_DEBUG 654 bool "Enable IOSF sideband access through debugfs" 655 depends on IOSF_MBI && DEBUG_FS 656 ---help--- 657 Select this option to expose the IOSF sideband access registers (MCR, 658 MDR, MCRX) through debugfs to write and read register information from 659 different units on the SoC. This is most useful for obtaining device 660 state information for debug and analysis. As this is a general access 661 mechanism, users of this option would have specific knowledge of the 662 device they want to access. 663 664 If you don't require the option or are in doubt, say N. 665 666config X86_RDC321X 667 bool "RDC R-321x SoC" 668 depends on X86_32 669 depends on X86_EXTENDED_PLATFORM 670 select M486 671 select X86_REBOOTFIXUPS 672 ---help--- 673 This option is needed for RDC R-321x system-on-chip, also known 674 as R-8610-(G). 675 If you don't have one of these chips, you should say N here. 676 677config X86_32_NON_STANDARD 678 bool "Support non-standard 32-bit SMP architectures" 679 depends on X86_32 && SMP 680 depends on X86_EXTENDED_PLATFORM 681 ---help--- 682 This option compiles in the bigsmp and STA2X11 default 683 subarchitectures. It is intended for a generic binary 684 kernel. If you select them all, kernel will probe it one by 685 one and will fallback to default. 686 687# Alphabetically sorted list of Non standard 32 bit platforms 688 689config X86_SUPPORTS_MEMORY_FAILURE 690 def_bool y 691 # MCE code calls memory_failure(): 692 depends on X86_MCE 693 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 694 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 695 depends on X86_64 || !SPARSEMEM 696 select ARCH_SUPPORTS_MEMORY_FAILURE 697 698config STA2X11 699 bool "STA2X11 Companion Chip Support" 700 depends on X86_32_NON_STANDARD && PCI 701 select ARCH_HAS_PHYS_TO_DMA 702 select X86_DEV_DMA_OPS 703 select X86_DMA_REMAP 704 select SWIOTLB 705 select MFD_STA2X11 706 select GPIOLIB 707 ---help--- 708 This adds support for boards based on the STA2X11 IO-Hub, 709 a.k.a. "ConneXt". The chip is used in place of the standard 710 PC chipset, so all "standard" peripherals are missing. If this 711 option is selected the kernel will still be able to boot on 712 standard PC machines. 713 714config X86_32_IRIS 715 tristate "Eurobraille/Iris poweroff module" 716 depends on X86_32 717 ---help--- 718 The Iris machines from EuroBraille do not have APM or ACPI support 719 to shut themselves down properly. A special I/O sequence is 720 needed to do so, which is what this module does at 721 kernel shutdown. 722 723 This is only for Iris machines from EuroBraille. 724 725 If unused, say N. 726 727config SCHED_OMIT_FRAME_POINTER 728 def_bool y 729 prompt "Single-depth WCHAN output" 730 depends on X86 731 ---help--- 732 Calculate simpler /proc/<PID>/wchan values. If this option 733 is disabled then wchan values will recurse back to the 734 caller function. This provides more accurate wchan values, 735 at the expense of slightly more scheduling overhead. 736 737 If in doubt, say "Y". 738 739menuconfig HYPERVISOR_GUEST 740 bool "Linux guest support" 741 ---help--- 742 Say Y here to enable options for running Linux under various hyper- 743 visors. This option enables basic hypervisor detection and platform 744 setup. 745 746 If you say N, all options in this submenu will be skipped and 747 disabled, and Linux guest support won't be built in. 748 749if HYPERVISOR_GUEST 750 751config PARAVIRT 752 bool "Enable paravirtualization code" 753 ---help--- 754 This changes the kernel so it can modify itself when it is run 755 under a hypervisor, potentially improving performance significantly 756 over full virtualization. However, when run without a hypervisor 757 the kernel is theoretically slower and slightly larger. 758 759config PARAVIRT_XXL 760 bool 761 762config PARAVIRT_DEBUG 763 bool "paravirt-ops debugging" 764 depends on PARAVIRT && DEBUG_KERNEL 765 ---help--- 766 Enable to debug paravirt_ops internals. Specifically, BUG if 767 a paravirt_op is missing when it is called. 768 769config PARAVIRT_SPINLOCKS 770 bool "Paravirtualization layer for spinlocks" 771 depends on PARAVIRT && SMP 772 ---help--- 773 Paravirtualized spinlocks allow a pvops backend to replace the 774 spinlock implementation with something virtualization-friendly 775 (for example, block the virtual CPU rather than spinning). 776 777 It has a minimal impact on native kernels and gives a nice performance 778 benefit on paravirtualized KVM / Xen kernels. 779 780 If you are unsure how to answer this question, answer Y. 781 782config QUEUED_LOCK_STAT 783 bool "Paravirt queued spinlock statistics" 784 depends on PARAVIRT_SPINLOCKS && DEBUG_FS 785 ---help--- 786 Enable the collection of statistical data on the slowpath 787 behavior of paravirtualized queued spinlocks and report 788 them on debugfs. 789 790source "arch/x86/xen/Kconfig" 791 792config KVM_GUEST 793 bool "KVM Guest support (including kvmclock)" 794 depends on PARAVIRT 795 select PARAVIRT_CLOCK 796 default y 797 ---help--- 798 This option enables various optimizations for running under the KVM 799 hypervisor. It includes a paravirtualized clock, so that instead 800 of relying on a PIT (or probably other) emulation by the 801 underlying device model, the host provides the guest with 802 timing infrastructure such as time of day, and system time 803 804config KVM_DEBUG_FS 805 bool "Enable debug information for KVM Guests in debugfs" 806 depends on KVM_GUEST && DEBUG_FS 807 ---help--- 808 This option enables collection of various statistics for KVM guest. 809 Statistics are displayed in debugfs filesystem. Enabling this option 810 may incur significant overhead. 811 812config PARAVIRT_TIME_ACCOUNTING 813 bool "Paravirtual steal time accounting" 814 depends on PARAVIRT 815 ---help--- 816 Select this option to enable fine granularity task steal time 817 accounting. Time spent executing other tasks in parallel with 818 the current vCPU is discounted from the vCPU power. To account for 819 that, there can be a small performance impact. 820 821 If in doubt, say N here. 822 823config PARAVIRT_CLOCK 824 bool 825 826config JAILHOUSE_GUEST 827 bool "Jailhouse non-root cell support" 828 depends on X86_64 && PCI 829 select X86_PM_TIMER 830 ---help--- 831 This option allows to run Linux as guest in a Jailhouse non-root 832 cell. You can leave this option disabled if you only want to start 833 Jailhouse and run Linux afterwards in the root cell. 834 835endif #HYPERVISOR_GUEST 836 837source "arch/x86/Kconfig.cpu" 838 839config HPET_TIMER 840 def_bool X86_64 841 prompt "HPET Timer Support" if X86_32 842 ---help--- 843 Use the IA-PC HPET (High Precision Event Timer) to manage 844 time in preference to the PIT and RTC, if a HPET is 845 present. 846 HPET is the next generation timer replacing legacy 8254s. 847 The HPET provides a stable time base on SMP 848 systems, unlike the TSC, but it is more expensive to access, 849 as it is off-chip. The interface used is documented 850 in the HPET spec, revision 1. 851 852 You can safely choose Y here. However, HPET will only be 853 activated if the platform and the BIOS support this feature. 854 Otherwise the 8254 will be used for timing services. 855 856 Choose N to continue using the legacy 8254 timer. 857 858config HPET_EMULATE_RTC 859 def_bool y 860 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 861 862config APB_TIMER 863 def_bool y if X86_INTEL_MID 864 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 865 select DW_APB_TIMER 866 depends on X86_INTEL_MID && SFI 867 help 868 APB timer is the replacement for 8254, HPET on X86 MID platforms. 869 The APBT provides a stable time base on SMP 870 systems, unlike the TSC, but it is more expensive to access, 871 as it is off-chip. APB timers are always running regardless of CPU 872 C states, they are used as per CPU clockevent device when possible. 873 874# Mark as expert because too many people got it wrong. 875# The code disables itself when not needed. 876config DMI 877 default y 878 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 879 bool "Enable DMI scanning" if EXPERT 880 ---help--- 881 Enabled scanning of DMI to identify machine quirks. Say Y 882 here unless you have verified that your setup is not 883 affected by entries in the DMI blacklist. Required by PNP 884 BIOS code. 885 886config GART_IOMMU 887 bool "Old AMD GART IOMMU support" 888 select IOMMU_HELPER 889 select SWIOTLB 890 depends on X86_64 && PCI && AMD_NB 891 ---help--- 892 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 893 GART based hardware IOMMUs. 894 895 The GART supports full DMA access for devices with 32-bit access 896 limitations, on systems with more than 3 GB. This is usually needed 897 for USB, sound, many IDE/SATA chipsets and some other devices. 898 899 Newer systems typically have a modern AMD IOMMU, supported via 900 the CONFIG_AMD_IOMMU=y config option. 901 902 In normal configurations this driver is only active when needed: 903 there's more than 3 GB of memory and the system contains a 904 32-bit limited device. 905 906 If unsure, say Y. 907 908config CALGARY_IOMMU 909 bool "IBM Calgary IOMMU support" 910 select IOMMU_HELPER 911 select SWIOTLB 912 depends on X86_64 && PCI 913 ---help--- 914 Support for hardware IOMMUs in IBM's xSeries x366 and x460 915 systems. Needed to run systems with more than 3GB of memory 916 properly with 32-bit PCI devices that do not support DAC 917 (Double Address Cycle). Calgary also supports bus level 918 isolation, where all DMAs pass through the IOMMU. This 919 prevents them from going anywhere except their intended 920 destination. This catches hard-to-find kernel bugs and 921 mis-behaving drivers and devices that do not use the DMA-API 922 properly to set up their DMA buffers. The IOMMU can be 923 turned off at boot time with the iommu=off parameter. 924 Normally the kernel will make the right choice by itself. 925 If unsure, say Y. 926 927config CALGARY_IOMMU_ENABLED_BY_DEFAULT 928 def_bool y 929 prompt "Should Calgary be enabled by default?" 930 depends on CALGARY_IOMMU 931 ---help--- 932 Should Calgary be enabled by default? if you choose 'y', Calgary 933 will be used (if it exists). If you choose 'n', Calgary will not be 934 used even if it exists. If you choose 'n' and would like to use 935 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 936 If unsure, say Y. 937 938config MAXSMP 939 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 940 depends on X86_64 && SMP && DEBUG_KERNEL 941 select CPUMASK_OFFSTACK 942 ---help--- 943 Enable maximum number of CPUS and NUMA Nodes for this architecture. 944 If unsure, say N. 945 946# 947# The maximum number of CPUs supported: 948# 949# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 950# and which can be configured interactively in the 951# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 952# 953# The ranges are different on 32-bit and 64-bit kernels, depending on 954# hardware capabilities and scalability features of the kernel. 955# 956# ( If MAXSMP is enabled we just use the highest possible value and disable 957# interactive configuration. ) 958# 959 960config NR_CPUS_RANGE_BEGIN 961 int 962 default NR_CPUS_RANGE_END if MAXSMP 963 default 1 if !SMP 964 default 2 965 966config NR_CPUS_RANGE_END 967 int 968 depends on X86_32 969 default 64 if SMP && X86_BIGSMP 970 default 8 if SMP && !X86_BIGSMP 971 default 1 if !SMP 972 973config NR_CPUS_RANGE_END 974 int 975 depends on X86_64 976 default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 977 default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 978 default 1 if !SMP 979 980config NR_CPUS_DEFAULT 981 int 982 depends on X86_32 983 default 32 if X86_BIGSMP 984 default 8 if SMP 985 default 1 if !SMP 986 987config NR_CPUS_DEFAULT 988 int 989 depends on X86_64 990 default 8192 if MAXSMP 991 default 64 if SMP 992 default 1 if !SMP 993 994config NR_CPUS 995 int "Maximum number of CPUs" if SMP && !MAXSMP 996 range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 997 default NR_CPUS_DEFAULT 998 ---help--- 999 This allows you to specify the maximum number of CPUs which this 1000 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 1001 supported value is 8192, otherwise the maximum value is 512. The 1002 minimum value which makes sense is 2. 1003 1004 This is purely to save memory: each supported CPU adds about 8KB 1005 to the kernel image. 1006 1007config SCHED_SMT 1008 bool "SMT (Hyperthreading) scheduler support" 1009 depends on SMP 1010 ---help--- 1011 SMT scheduler support improves the CPU scheduler's decision making 1012 when dealing with Intel Pentium 4 chips with HyperThreading at a 1013 cost of slightly increased overhead in some places. If unsure say 1014 N here. 1015 1016config SCHED_MC 1017 def_bool y 1018 prompt "Multi-core scheduler support" 1019 depends on SMP 1020 ---help--- 1021 Multi-core scheduler support improves the CPU scheduler's decision 1022 making when dealing with multi-core CPU chips at a cost of slightly 1023 increased overhead in some places. If unsure say N here. 1024 1025config SCHED_MC_PRIO 1026 bool "CPU core priorities scheduler support" 1027 depends on SCHED_MC && CPU_SUP_INTEL 1028 select X86_INTEL_PSTATE 1029 select CPU_FREQ 1030 default y 1031 ---help--- 1032 Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1033 core ordering determined at manufacturing time, which allows 1034 certain cores to reach higher turbo frequencies (when running 1035 single threaded workloads) than others. 1036 1037 Enabling this kernel feature teaches the scheduler about 1038 the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1039 scheduler's CPU selection logic accordingly, so that higher 1040 overall system performance can be achieved. 1041 1042 This feature will have no effect on CPUs without this feature. 1043 1044 If unsure say Y here. 1045 1046config UP_LATE_INIT 1047 def_bool y 1048 depends on !SMP && X86_LOCAL_APIC 1049 1050config X86_UP_APIC 1051 bool "Local APIC support on uniprocessors" if !PCI_MSI 1052 default PCI_MSI 1053 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 1054 ---help--- 1055 A local APIC (Advanced Programmable Interrupt Controller) is an 1056 integrated interrupt controller in the CPU. If you have a single-CPU 1057 system which has a processor with a local APIC, you can say Y here to 1058 enable and use it. If you say Y here even though your machine doesn't 1059 have a local APIC, then the kernel will still run with no slowdown at 1060 all. The local APIC supports CPU-generated self-interrupts (timer, 1061 performance counters), and the NMI watchdog which detects hard 1062 lockups. 1063 1064config X86_UP_IOAPIC 1065 bool "IO-APIC support on uniprocessors" 1066 depends on X86_UP_APIC 1067 ---help--- 1068 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1069 SMP-capable replacement for PC-style interrupt controllers. Most 1070 SMP systems and many recent uniprocessor systems have one. 1071 1072 If you have a single-CPU system with an IO-APIC, you can say Y here 1073 to use it. If you say Y here even though your machine doesn't have 1074 an IO-APIC, then the kernel will still run with no slowdown at all. 1075 1076config X86_LOCAL_APIC 1077 def_bool y 1078 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1079 select IRQ_DOMAIN_HIERARCHY 1080 select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1081 1082config X86_IO_APIC 1083 def_bool y 1084 depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1085 1086config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 1087 bool "Reroute for broken boot IRQs" 1088 depends on X86_IO_APIC 1089 ---help--- 1090 This option enables a workaround that fixes a source of 1091 spurious interrupts. This is recommended when threaded 1092 interrupt handling is used on systems where the generation of 1093 superfluous "boot interrupts" cannot be disabled. 1094 1095 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 1096 entry in the chipset's IO-APIC is masked (as, e.g. the RT 1097 kernel does during interrupt handling). On chipsets where this 1098 boot IRQ generation cannot be disabled, this workaround keeps 1099 the original IRQ line masked so that only the equivalent "boot 1100 IRQ" is delivered to the CPUs. The workaround also tells the 1101 kernel to set up the IRQ handler on the boot IRQ line. In this 1102 way only one interrupt is delivered to the kernel. Otherwise 1103 the spurious second interrupt may cause the kernel to bring 1104 down (vital) interrupt lines. 1105 1106 Only affects "broken" chipsets. Interrupt sharing may be 1107 increased on these systems. 1108 1109config X86_MCE 1110 bool "Machine Check / overheating reporting" 1111 select GENERIC_ALLOCATOR 1112 default y 1113 ---help--- 1114 Machine Check support allows the processor to notify the 1115 kernel if it detects a problem (e.g. overheating, data corruption). 1116 The action the kernel takes depends on the severity of the problem, 1117 ranging from warning messages to halting the machine. 1118 1119config X86_MCELOG_LEGACY 1120 bool "Support for deprecated /dev/mcelog character device" 1121 depends on X86_MCE 1122 ---help--- 1123 Enable support for /dev/mcelog which is needed by the old mcelog 1124 userspace logging daemon. Consider switching to the new generation 1125 rasdaemon solution. 1126 1127config X86_MCE_INTEL 1128 def_bool y 1129 prompt "Intel MCE features" 1130 depends on X86_MCE && X86_LOCAL_APIC 1131 ---help--- 1132 Additional support for intel specific MCE features such as 1133 the thermal monitor. 1134 1135config X86_MCE_AMD 1136 def_bool y 1137 prompt "AMD MCE features" 1138 depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 1139 ---help--- 1140 Additional support for AMD specific MCE features such as 1141 the DRAM Error Threshold. 1142 1143config X86_ANCIENT_MCE 1144 bool "Support for old Pentium 5 / WinChip machine checks" 1145 depends on X86_32 && X86_MCE 1146 ---help--- 1147 Include support for machine check handling on old Pentium 5 or WinChip 1148 systems. These typically need to be enabled explicitly on the command 1149 line. 1150 1151config X86_MCE_THRESHOLD 1152 depends on X86_MCE_AMD || X86_MCE_INTEL 1153 def_bool y 1154 1155config X86_MCE_INJECT 1156 depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1157 tristate "Machine check injector support" 1158 ---help--- 1159 Provide support for injecting machine checks for testing purposes. 1160 If you don't know what a machine check is and you don't do kernel 1161 QA it is safe to say n. 1162 1163config X86_THERMAL_VECTOR 1164 def_bool y 1165 depends on X86_MCE_INTEL 1166 1167source "arch/x86/events/Kconfig" 1168 1169config X86_LEGACY_VM86 1170 bool "Legacy VM86 support" 1171 depends on X86_32 1172 ---help--- 1173 This option allows user programs to put the CPU into V8086 1174 mode, which is an 80286-era approximation of 16-bit real mode. 1175 1176 Some very old versions of X and/or vbetool require this option 1177 for user mode setting. Similarly, DOSEMU will use it if 1178 available to accelerate real mode DOS programs. However, any 1179 recent version of DOSEMU, X, or vbetool should be fully 1180 functional even without kernel VM86 support, as they will all 1181 fall back to software emulation. Nevertheless, if you are using 1182 a 16-bit DOS program where 16-bit performance matters, vm86 1183 mode might be faster than emulation and you might want to 1184 enable this option. 1185 1186 Note that any app that works on a 64-bit kernel is unlikely to 1187 need this option, as 64-bit kernels don't, and can't, support 1188 V8086 mode. This option is also unrelated to 16-bit protected 1189 mode and is not needed to run most 16-bit programs under Wine. 1190 1191 Enabling this option increases the complexity of the kernel 1192 and slows down exception handling a tiny bit. 1193 1194 If unsure, say N here. 1195 1196config VM86 1197 bool 1198 default X86_LEGACY_VM86 1199 1200config X86_16BIT 1201 bool "Enable support for 16-bit segments" if EXPERT 1202 default y 1203 depends on MODIFY_LDT_SYSCALL 1204 ---help--- 1205 This option is required by programs like Wine to run 16-bit 1206 protected mode legacy code on x86 processors. Disabling 1207 this option saves about 300 bytes on i386, or around 6K text 1208 plus 16K runtime memory on x86-64, 1209 1210config X86_ESPFIX32 1211 def_bool y 1212 depends on X86_16BIT && X86_32 1213 1214config X86_ESPFIX64 1215 def_bool y 1216 depends on X86_16BIT && X86_64 1217 1218config X86_VSYSCALL_EMULATION 1219 bool "Enable vsyscall emulation" if EXPERT 1220 default y 1221 depends on X86_64 1222 ---help--- 1223 This enables emulation of the legacy vsyscall page. Disabling 1224 it is roughly equivalent to booting with vsyscall=none, except 1225 that it will also disable the helpful warning if a program 1226 tries to use a vsyscall. With this option set to N, offending 1227 programs will just segfault, citing addresses of the form 1228 0xffffffffff600?00. 1229 1230 This option is required by many programs built before 2013, and 1231 care should be used even with newer programs if set to N. 1232 1233 Disabling this option saves about 7K of kernel size and 1234 possibly 4K of additional runtime pagetable memory. 1235 1236config TOSHIBA 1237 tristate "Toshiba Laptop support" 1238 depends on X86_32 1239 ---help--- 1240 This adds a driver to safely access the System Management Mode of 1241 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1242 not work on models with a Phoenix BIOS. The System Management Mode 1243 is used to set the BIOS and power saving options on Toshiba portables. 1244 1245 For information on utilities to make use of this driver see the 1246 Toshiba Linux utilities web site at: 1247 <http://www.buzzard.org.uk/toshiba/>. 1248 1249 Say Y if you intend to run this kernel on a Toshiba portable. 1250 Say N otherwise. 1251 1252config I8K 1253 tristate "Dell i8k legacy laptop support" 1254 select HWMON 1255 select SENSORS_DELL_SMM 1256 ---help--- 1257 This option enables legacy /proc/i8k userspace interface in hwmon 1258 dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1259 temperature and allows controlling fan speeds of Dell laptops via 1260 System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1261 it reports also power and hotkey status. For fan speed control is 1262 needed userspace package i8kutils. 1263 1264 Say Y if you intend to run this kernel on old Dell laptops or want to 1265 use userspace package i8kutils. 1266 Say N otherwise. 1267 1268config X86_REBOOTFIXUPS 1269 bool "Enable X86 board specific fixups for reboot" 1270 depends on X86_32 1271 ---help--- 1272 This enables chipset and/or board specific fixups to be done 1273 in order to get reboot to work correctly. This is only needed on 1274 some combinations of hardware and BIOS. The symptom, for which 1275 this config is intended, is when reboot ends with a stalled/hung 1276 system. 1277 1278 Currently, the only fixup is for the Geode machines using 1279 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1280 1281 Say Y if you want to enable the fixup. Currently, it's safe to 1282 enable this option even if you don't need it. 1283 Say N otherwise. 1284 1285config MICROCODE 1286 bool "CPU microcode loading support" 1287 default y 1288 depends on CPU_SUP_AMD || CPU_SUP_INTEL 1289 select FW_LOADER 1290 ---help--- 1291 If you say Y here, you will be able to update the microcode on 1292 Intel and AMD processors. The Intel support is for the IA32 family, 1293 e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 1294 AMD support is for families 0x10 and later. You will obviously need 1295 the actual microcode binary data itself which is not shipped with 1296 the Linux kernel. 1297 1298 The preferred method to load microcode from a detached initrd is described 1299 in Documentation/x86/microcode.txt. For that you need to enable 1300 CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 1301 initrd for microcode blobs. 1302 1303 In addition, you can build the microcode into the kernel. For that you 1304 need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1305 config option. 1306 1307config MICROCODE_INTEL 1308 bool "Intel microcode loading support" 1309 depends on MICROCODE 1310 default MICROCODE 1311 select FW_LOADER 1312 ---help--- 1313 This options enables microcode patch loading support for Intel 1314 processors. 1315 1316 For the current Intel microcode data package go to 1317 <https://downloadcenter.intel.com> and search for 1318 'Linux Processor Microcode Data File'. 1319 1320config MICROCODE_AMD 1321 bool "AMD microcode loading support" 1322 depends on MICROCODE 1323 select FW_LOADER 1324 ---help--- 1325 If you select this option, microcode patch loading support for AMD 1326 processors will be enabled. 1327 1328config MICROCODE_OLD_INTERFACE 1329 def_bool y 1330 depends on MICROCODE 1331 1332config X86_MSR 1333 tristate "/dev/cpu/*/msr - Model-specific register support" 1334 ---help--- 1335 This device gives privileged processes access to the x86 1336 Model-Specific Registers (MSRs). It is a character device with 1337 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1338 MSR accesses are directed to a specific CPU on multi-processor 1339 systems. 1340 1341config X86_CPUID 1342 tristate "/dev/cpu/*/cpuid - CPU information support" 1343 ---help--- 1344 This device gives processes access to the x86 CPUID instruction to 1345 be executed on a specific processor. It is a character device 1346 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1347 /dev/cpu/31/cpuid. 1348 1349choice 1350 prompt "High Memory Support" 1351 default HIGHMEM4G 1352 depends on X86_32 1353 1354config NOHIGHMEM 1355 bool "off" 1356 ---help--- 1357 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1358 However, the address space of 32-bit x86 processors is only 4 1359 Gigabytes large. That means that, if you have a large amount of 1360 physical memory, not all of it can be "permanently mapped" by the 1361 kernel. The physical memory that's not permanently mapped is called 1362 "high memory". 1363 1364 If you are compiling a kernel which will never run on a machine with 1365 more than 1 Gigabyte total physical RAM, answer "off" here (default 1366 choice and suitable for most users). This will result in a "3GB/1GB" 1367 split: 3GB are mapped so that each process sees a 3GB virtual memory 1368 space and the remaining part of the 4GB virtual memory space is used 1369 by the kernel to permanently map as much physical memory as 1370 possible. 1371 1372 If the machine has between 1 and 4 Gigabytes physical RAM, then 1373 answer "4GB" here. 1374 1375 If more than 4 Gigabytes is used then answer "64GB" here. This 1376 selection turns Intel PAE (Physical Address Extension) mode on. 1377 PAE implements 3-level paging on IA32 processors. PAE is fully 1378 supported by Linux, PAE mode is implemented on all recent Intel 1379 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1380 then the kernel will not boot on CPUs that don't support PAE! 1381 1382 The actual amount of total physical memory will either be 1383 auto detected or can be forced by using a kernel command line option 1384 such as "mem=256M". (Try "man bootparam" or see the documentation of 1385 your boot loader (lilo or loadlin) about how to pass options to the 1386 kernel at boot time.) 1387 1388 If unsure, say "off". 1389 1390config HIGHMEM4G 1391 bool "4GB" 1392 ---help--- 1393 Select this if you have a 32-bit processor and between 1 and 4 1394 gigabytes of physical RAM. 1395 1396config HIGHMEM64G 1397 bool "64GB" 1398 depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1399 select X86_PAE 1400 ---help--- 1401 Select this if you have a 32-bit processor and more than 4 1402 gigabytes of physical RAM. 1403 1404endchoice 1405 1406choice 1407 prompt "Memory split" if EXPERT 1408 default VMSPLIT_3G 1409 depends on X86_32 1410 ---help--- 1411 Select the desired split between kernel and user memory. 1412 1413 If the address range available to the kernel is less than the 1414 physical memory installed, the remaining memory will be available 1415 as "high memory". Accessing high memory is a little more costly 1416 than low memory, as it needs to be mapped into the kernel first. 1417 Note that increasing the kernel address space limits the range 1418 available to user programs, making the address space there 1419 tighter. Selecting anything other than the default 3G/1G split 1420 will also likely make your kernel incompatible with binary-only 1421 kernel modules. 1422 1423 If you are not absolutely sure what you are doing, leave this 1424 option alone! 1425 1426 config VMSPLIT_3G 1427 bool "3G/1G user/kernel split" 1428 config VMSPLIT_3G_OPT 1429 depends on !X86_PAE 1430 bool "3G/1G user/kernel split (for full 1G low memory)" 1431 config VMSPLIT_2G 1432 bool "2G/2G user/kernel split" 1433 config VMSPLIT_2G_OPT 1434 depends on !X86_PAE 1435 bool "2G/2G user/kernel split (for full 2G low memory)" 1436 config VMSPLIT_1G 1437 bool "1G/3G user/kernel split" 1438endchoice 1439 1440config PAGE_OFFSET 1441 hex 1442 default 0xB0000000 if VMSPLIT_3G_OPT 1443 default 0x80000000 if VMSPLIT_2G 1444 default 0x78000000 if VMSPLIT_2G_OPT 1445 default 0x40000000 if VMSPLIT_1G 1446 default 0xC0000000 1447 depends on X86_32 1448 1449config HIGHMEM 1450 def_bool y 1451 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1452 1453config X86_PAE 1454 bool "PAE (Physical Address Extension) Support" 1455 depends on X86_32 && !HIGHMEM4G 1456 select PHYS_ADDR_T_64BIT 1457 select SWIOTLB 1458 ---help--- 1459 PAE is required for NX support, and furthermore enables 1460 larger swapspace support for non-overcommit purposes. It 1461 has the cost of more pagetable lookup overhead, and also 1462 consumes more pagetable space per process. 1463 1464config X86_5LEVEL 1465 bool "Enable 5-level page tables support" 1466 select DYNAMIC_MEMORY_LAYOUT 1467 select SPARSEMEM_VMEMMAP 1468 depends on X86_64 1469 ---help--- 1470 5-level paging enables access to larger address space: 1471 upto 128 PiB of virtual address space and 4 PiB of 1472 physical address space. 1473 1474 It will be supported by future Intel CPUs. 1475 1476 A kernel with the option enabled can be booted on machines that 1477 support 4- or 5-level paging. 1478 1479 See Documentation/x86/x86_64/5level-paging.txt for more 1480 information. 1481 1482 Say N if unsure. 1483 1484config X86_DIRECT_GBPAGES 1485 def_bool y 1486 depends on X86_64 && !DEBUG_PAGEALLOC 1487 ---help--- 1488 Certain kernel features effectively disable kernel 1489 linear 1 GB mappings (even if the CPU otherwise 1490 supports them), so don't confuse the user by printing 1491 that we have them enabled. 1492 1493config X86_CPA_STATISTICS 1494 bool "Enable statistic for Change Page Attribute" 1495 depends on DEBUG_FS 1496 ---help--- 1497 Expose statistics about the Change Page Attribute mechanims, which 1498 helps to determine the effectivness of preserving large and huge 1499 page mappings when mapping protections are changed. 1500 1501config ARCH_HAS_MEM_ENCRYPT 1502 def_bool y 1503 1504config AMD_MEM_ENCRYPT 1505 bool "AMD Secure Memory Encryption (SME) support" 1506 depends on X86_64 && CPU_SUP_AMD 1507 select DYNAMIC_PHYSICAL_MASK 1508 ---help--- 1509 Say yes to enable support for the encryption of system memory. 1510 This requires an AMD processor that supports Secure Memory 1511 Encryption (SME). 1512 1513config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 1514 bool "Activate AMD Secure Memory Encryption (SME) by default" 1515 default y 1516 depends on AMD_MEM_ENCRYPT 1517 ---help--- 1518 Say yes to have system memory encrypted by default if running on 1519 an AMD processor that supports Secure Memory Encryption (SME). 1520 1521 If set to Y, then the encryption of system memory can be 1522 deactivated with the mem_encrypt=off command line option. 1523 1524 If set to N, then the encryption of system memory can be 1525 activated with the mem_encrypt=on command line option. 1526 1527config ARCH_USE_MEMREMAP_PROT 1528 def_bool y 1529 depends on AMD_MEM_ENCRYPT 1530 1531# Common NUMA Features 1532config NUMA 1533 bool "Numa Memory Allocation and Scheduler Support" 1534 depends on SMP 1535 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1536 default y if X86_BIGSMP 1537 ---help--- 1538 Enable NUMA (Non Uniform Memory Access) support. 1539 1540 The kernel will try to allocate memory used by a CPU on the 1541 local memory controller of the CPU and add some more 1542 NUMA awareness to the kernel. 1543 1544 For 64-bit this is recommended if the system is Intel Core i7 1545 (or later), AMD Opteron, or EM64T NUMA. 1546 1547 For 32-bit this is only needed if you boot a 32-bit 1548 kernel on a 64-bit NUMA platform. 1549 1550 Otherwise, you should say N. 1551 1552config AMD_NUMA 1553 def_bool y 1554 prompt "Old style AMD Opteron NUMA detection" 1555 depends on X86_64 && NUMA && PCI 1556 ---help--- 1557 Enable AMD NUMA node topology detection. You should say Y here if 1558 you have a multi processor AMD system. This uses an old method to 1559 read the NUMA configuration directly from the builtin Northbridge 1560 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1561 which also takes priority if both are compiled in. 1562 1563config X86_64_ACPI_NUMA 1564 def_bool y 1565 prompt "ACPI NUMA detection" 1566 depends on X86_64 && NUMA && ACPI && PCI 1567 select ACPI_NUMA 1568 ---help--- 1569 Enable ACPI SRAT based node topology detection. 1570 1571# Some NUMA nodes have memory ranges that span 1572# other nodes. Even though a pfn is valid and 1573# between a node's start and end pfns, it may not 1574# reside on that node. See memmap_init_zone() 1575# for details. 1576config NODES_SPAN_OTHER_NODES 1577 def_bool y 1578 depends on X86_64_ACPI_NUMA 1579 1580config NUMA_EMU 1581 bool "NUMA emulation" 1582 depends on NUMA 1583 ---help--- 1584 Enable NUMA emulation. A flat machine will be split 1585 into virtual nodes when booted with "numa=fake=N", where N is the 1586 number of nodes. This is only useful for debugging. 1587 1588config NODES_SHIFT 1589 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1590 range 1 10 1591 default "10" if MAXSMP 1592 default "6" if X86_64 1593 default "3" 1594 depends on NEED_MULTIPLE_NODES 1595 ---help--- 1596 Specify the maximum number of NUMA Nodes available on the target 1597 system. Increases memory reserved to accommodate various tables. 1598 1599config ARCH_HAVE_MEMORY_PRESENT 1600 def_bool y 1601 depends on X86_32 && DISCONTIGMEM 1602 1603config ARCH_FLATMEM_ENABLE 1604 def_bool y 1605 depends on X86_32 && !NUMA 1606 1607config ARCH_DISCONTIGMEM_ENABLE 1608 def_bool y 1609 depends on NUMA && X86_32 1610 1611config ARCH_DISCONTIGMEM_DEFAULT 1612 def_bool y 1613 depends on NUMA && X86_32 1614 1615config ARCH_SPARSEMEM_ENABLE 1616 def_bool y 1617 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1618 select SPARSEMEM_STATIC if X86_32 1619 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1620 1621config ARCH_SPARSEMEM_DEFAULT 1622 def_bool y 1623 depends on X86_64 1624 1625config ARCH_SELECT_MEMORY_MODEL 1626 def_bool y 1627 depends on ARCH_SPARSEMEM_ENABLE 1628 1629config ARCH_MEMORY_PROBE 1630 bool "Enable sysfs memory/probe interface" 1631 depends on X86_64 && MEMORY_HOTPLUG 1632 help 1633 This option enables a sysfs memory/probe interface for testing. 1634 See Documentation/memory-hotplug.txt for more information. 1635 If you are unsure how to answer this question, answer N. 1636 1637config ARCH_PROC_KCORE_TEXT 1638 def_bool y 1639 depends on X86_64 && PROC_KCORE 1640 1641config ILLEGAL_POINTER_VALUE 1642 hex 1643 default 0 if X86_32 1644 default 0xdead000000000000 if X86_64 1645 1646config X86_PMEM_LEGACY_DEVICE 1647 bool 1648 1649config X86_PMEM_LEGACY 1650 tristate "Support non-standard NVDIMMs and ADR protected memory" 1651 depends on PHYS_ADDR_T_64BIT 1652 depends on BLK_DEV 1653 select X86_PMEM_LEGACY_DEVICE 1654 select LIBNVDIMM 1655 help 1656 Treat memory marked using the non-standard e820 type of 12 as used 1657 by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1658 The kernel will offer these regions to the 'pmem' driver so 1659 they can be used for persistent storage. 1660 1661 Say Y if unsure. 1662 1663config HIGHPTE 1664 bool "Allocate 3rd-level pagetables from highmem" 1665 depends on HIGHMEM 1666 ---help--- 1667 The VM uses one page table entry for each page of physical memory. 1668 For systems with a lot of RAM, this can be wasteful of precious 1669 low memory. Setting this option will put user-space page table 1670 entries in high memory. 1671 1672config X86_CHECK_BIOS_CORRUPTION 1673 bool "Check for low memory corruption" 1674 ---help--- 1675 Periodically check for memory corruption in low memory, which 1676 is suspected to be caused by BIOS. Even when enabled in the 1677 configuration, it is disabled at runtime. Enable it by 1678 setting "memory_corruption_check=1" on the kernel command 1679 line. By default it scans the low 64k of memory every 60 1680 seconds; see the memory_corruption_check_size and 1681 memory_corruption_check_period parameters in 1682 Documentation/admin-guide/kernel-parameters.rst to adjust this. 1683 1684 When enabled with the default parameters, this option has 1685 almost no overhead, as it reserves a relatively small amount 1686 of memory and scans it infrequently. It both detects corruption 1687 and prevents it from affecting the running system. 1688 1689 It is, however, intended as a diagnostic tool; if repeatable 1690 BIOS-originated corruption always affects the same memory, 1691 you can use memmap= to prevent the kernel from using that 1692 memory. 1693 1694config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1695 bool "Set the default setting of memory_corruption_check" 1696 depends on X86_CHECK_BIOS_CORRUPTION 1697 default y 1698 ---help--- 1699 Set whether the default state of memory_corruption_check is 1700 on or off. 1701 1702config X86_RESERVE_LOW 1703 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1704 default 64 1705 range 4 640 1706 ---help--- 1707 Specify the amount of low memory to reserve for the BIOS. 1708 1709 The first page contains BIOS data structures that the kernel 1710 must not use, so that page must always be reserved. 1711 1712 By default we reserve the first 64K of physical RAM, as a 1713 number of BIOSes are known to corrupt that memory range 1714 during events such as suspend/resume or monitor cable 1715 insertion, so it must not be used by the kernel. 1716 1717 You can set this to 4 if you are absolutely sure that you 1718 trust the BIOS to get all its memory reservations and usages 1719 right. If you know your BIOS have problems beyond the 1720 default 64K area, you can set this to 640 to avoid using the 1721 entire low memory range. 1722 1723 If you have doubts about the BIOS (e.g. suspend/resume does 1724 not work or there's kernel crashes after certain hardware 1725 hotplug events) then you might want to enable 1726 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1727 typical corruption patterns. 1728 1729 Leave this to the default value of 64 if you are unsure. 1730 1731config MATH_EMULATION 1732 bool 1733 depends on MODIFY_LDT_SYSCALL 1734 prompt "Math emulation" if X86_32 1735 ---help--- 1736 Linux can emulate a math coprocessor (used for floating point 1737 operations) if you don't have one. 486DX and Pentium processors have 1738 a math coprocessor built in, 486SX and 386 do not, unless you added 1739 a 487DX or 387, respectively. (The messages during boot time can 1740 give you some hints here ["man dmesg"].) Everyone needs either a 1741 coprocessor or this emulation. 1742 1743 If you don't have a math coprocessor, you need to say Y here; if you 1744 say Y here even though you have a coprocessor, the coprocessor will 1745 be used nevertheless. (This behavior can be changed with the kernel 1746 command line option "no387", which comes handy if your coprocessor 1747 is broken. Try "man bootparam" or see the documentation of your boot 1748 loader (lilo or loadlin) about how to pass options to the kernel at 1749 boot time.) This means that it is a good idea to say Y here if you 1750 intend to use this kernel on different machines. 1751 1752 More information about the internals of the Linux math coprocessor 1753 emulation can be found in <file:arch/x86/math-emu/README>. 1754 1755 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1756 kernel, it won't hurt. 1757 1758config MTRR 1759 def_bool y 1760 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1761 ---help--- 1762 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1763 the Memory Type Range Registers (MTRRs) may be used to control 1764 processor access to memory ranges. This is most useful if you have 1765 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1766 allows bus write transfers to be combined into a larger transfer 1767 before bursting over the PCI/AGP bus. This can increase performance 1768 of image write operations 2.5 times or more. Saying Y here creates a 1769 /proc/mtrr file which may be used to manipulate your processor's 1770 MTRRs. Typically the X server should use this. 1771 1772 This code has a reasonably generic interface so that similar 1773 control registers on other processors can be easily supported 1774 as well: 1775 1776 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1777 Registers (ARRs) which provide a similar functionality to MTRRs. For 1778 these, the ARRs are used to emulate the MTRRs. 1779 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1780 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1781 write-combining. All of these processors are supported by this code 1782 and it makes sense to say Y here if you have one of them. 1783 1784 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1785 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1786 can lead to all sorts of problems, so it's good to say Y here. 1787 1788 You can safely say Y even if your machine doesn't have MTRRs, you'll 1789 just add about 9 KB to your kernel. 1790 1791 See <file:Documentation/x86/mtrr.txt> for more information. 1792 1793config MTRR_SANITIZER 1794 def_bool y 1795 prompt "MTRR cleanup support" 1796 depends on MTRR 1797 ---help--- 1798 Convert MTRR layout from continuous to discrete, so X drivers can 1799 add writeback entries. 1800 1801 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1802 The largest mtrr entry size for a continuous block can be set with 1803 mtrr_chunk_size. 1804 1805 If unsure, say Y. 1806 1807config MTRR_SANITIZER_ENABLE_DEFAULT 1808 int "MTRR cleanup enable value (0-1)" 1809 range 0 1 1810 default "0" 1811 depends on MTRR_SANITIZER 1812 ---help--- 1813 Enable mtrr cleanup default value 1814 1815config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1816 int "MTRR cleanup spare reg num (0-7)" 1817 range 0 7 1818 default "1" 1819 depends on MTRR_SANITIZER 1820 ---help--- 1821 mtrr cleanup spare entries default, it can be changed via 1822 mtrr_spare_reg_nr=N on the kernel command line. 1823 1824config X86_PAT 1825 def_bool y 1826 prompt "x86 PAT support" if EXPERT 1827 depends on MTRR 1828 ---help--- 1829 Use PAT attributes to setup page level cache control. 1830 1831 PATs are the modern equivalents of MTRRs and are much more 1832 flexible than MTRRs. 1833 1834 Say N here if you see bootup problems (boot crash, boot hang, 1835 spontaneous reboots) or a non-working video driver. 1836 1837 If unsure, say Y. 1838 1839config ARCH_USES_PG_UNCACHED 1840 def_bool y 1841 depends on X86_PAT 1842 1843config ARCH_RANDOM 1844 def_bool y 1845 prompt "x86 architectural random number generator" if EXPERT 1846 ---help--- 1847 Enable the x86 architectural RDRAND instruction 1848 (Intel Bull Mountain technology) to generate random numbers. 1849 If supported, this is a high bandwidth, cryptographically 1850 secure hardware random number generator. 1851 1852config X86_SMAP 1853 def_bool y 1854 prompt "Supervisor Mode Access Prevention" if EXPERT 1855 ---help--- 1856 Supervisor Mode Access Prevention (SMAP) is a security 1857 feature in newer Intel processors. There is a small 1858 performance cost if this enabled and turned on; there is 1859 also a small increase in the kernel size if this is enabled. 1860 1861 If unsure, say Y. 1862 1863config X86_INTEL_UMIP 1864 def_bool y 1865 depends on CPU_SUP_INTEL 1866 prompt "Intel User Mode Instruction Prevention" if EXPERT 1867 ---help--- 1868 The User Mode Instruction Prevention (UMIP) is a security 1869 feature in newer Intel processors. If enabled, a general 1870 protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1871 or STR instructions are executed in user mode. These instructions 1872 unnecessarily expose information about the hardware state. 1873 1874 The vast majority of applications do not use these instructions. 1875 For the very few that do, software emulation is provided in 1876 specific cases in protected and virtual-8086 modes. Emulated 1877 results are dummy. 1878 1879config X86_INTEL_MPX 1880 prompt "Intel MPX (Memory Protection Extensions)" 1881 def_bool n 1882 # Note: only available in 64-bit mode due to VMA flags shortage 1883 depends on CPU_SUP_INTEL && X86_64 1884 select ARCH_USES_HIGH_VMA_FLAGS 1885 ---help--- 1886 MPX provides hardware features that can be used in 1887 conjunction with compiler-instrumented code to check 1888 memory references. It is designed to detect buffer 1889 overflow or underflow bugs. 1890 1891 This option enables running applications which are 1892 instrumented or otherwise use MPX. It does not use MPX 1893 itself inside the kernel or to protect the kernel 1894 against bad memory references. 1895 1896 Enabling this option will make the kernel larger: 1897 ~8k of kernel text and 36 bytes of data on a 64-bit 1898 defconfig. It adds a long to the 'mm_struct' which 1899 will increase the kernel memory overhead of each 1900 process and adds some branches to paths used during 1901 exec() and munmap(). 1902 1903 For details, see Documentation/x86/intel_mpx.txt 1904 1905 If unsure, say N. 1906 1907config X86_INTEL_MEMORY_PROTECTION_KEYS 1908 prompt "Intel Memory Protection Keys" 1909 def_bool y 1910 # Note: only available in 64-bit mode 1911 depends on CPU_SUP_INTEL && X86_64 1912 select ARCH_USES_HIGH_VMA_FLAGS 1913 select ARCH_HAS_PKEYS 1914 ---help--- 1915 Memory Protection Keys provides a mechanism for enforcing 1916 page-based protections, but without requiring modification of the 1917 page tables when an application changes protection domains. 1918 1919 For details, see Documentation/x86/protection-keys.txt 1920 1921 If unsure, say y. 1922 1923config EFI 1924 bool "EFI runtime service support" 1925 depends on ACPI 1926 select UCS2_STRING 1927 select EFI_RUNTIME_WRAPPERS 1928 ---help--- 1929 This enables the kernel to use EFI runtime services that are 1930 available (such as the EFI variable services). 1931 1932 This option is only useful on systems that have EFI firmware. 1933 In addition, you should use the latest ELILO loader available 1934 at <http://elilo.sourceforge.net> in order to take advantage 1935 of EFI runtime services. However, even with this option, the 1936 resultant kernel should continue to boot on existing non-EFI 1937 platforms. 1938 1939config EFI_STUB 1940 bool "EFI stub support" 1941 depends on EFI && !X86_USE_3DNOW 1942 select RELOCATABLE 1943 ---help--- 1944 This kernel feature allows a bzImage to be loaded directly 1945 by EFI firmware without the use of a bootloader. 1946 1947 See Documentation/efi-stub.txt for more information. 1948 1949config EFI_MIXED 1950 bool "EFI mixed-mode support" 1951 depends on EFI_STUB && X86_64 1952 ---help--- 1953 Enabling this feature allows a 64-bit kernel to be booted 1954 on a 32-bit firmware, provided that your CPU supports 64-bit 1955 mode. 1956 1957 Note that it is not possible to boot a mixed-mode enabled 1958 kernel via the EFI boot stub - a bootloader that supports 1959 the EFI handover protocol must be used. 1960 1961 If unsure, say N. 1962 1963config SECCOMP 1964 def_bool y 1965 prompt "Enable seccomp to safely compute untrusted bytecode" 1966 ---help--- 1967 This kernel feature is useful for number crunching applications 1968 that may need to compute untrusted bytecode during their 1969 execution. By using pipes or other transports made available to 1970 the process as file descriptors supporting the read/write 1971 syscalls, it's possible to isolate those applications in 1972 their own address space using seccomp. Once seccomp is 1973 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1974 and the task is only allowed to execute a few safe syscalls 1975 defined by each seccomp mode. 1976 1977 If unsure, say Y. Only embedded should say N here. 1978 1979source kernel/Kconfig.hz 1980 1981config KEXEC 1982 bool "kexec system call" 1983 select KEXEC_CORE 1984 ---help--- 1985 kexec is a system call that implements the ability to shutdown your 1986 current kernel, and to start another kernel. It is like a reboot 1987 but it is independent of the system firmware. And like a reboot 1988 you can start any kernel with it, not just Linux. 1989 1990 The name comes from the similarity to the exec system call. 1991 1992 It is an ongoing process to be certain the hardware in a machine 1993 is properly shutdown, so do not be surprised if this code does not 1994 initially work for you. As of this writing the exact hardware 1995 interface is strongly in flux, so no good recommendation can be 1996 made. 1997 1998config KEXEC_FILE 1999 bool "kexec file based system call" 2000 select KEXEC_CORE 2001 select BUILD_BIN2C 2002 depends on X86_64 2003 depends on CRYPTO=y 2004 depends on CRYPTO_SHA256=y 2005 ---help--- 2006 This is new version of kexec system call. This system call is 2007 file based and takes file descriptors as system call argument 2008 for kernel and initramfs as opposed to list of segments as 2009 accepted by previous system call. 2010 2011config ARCH_HAS_KEXEC_PURGATORY 2012 def_bool KEXEC_FILE 2013 2014config KEXEC_VERIFY_SIG 2015 bool "Verify kernel signature during kexec_file_load() syscall" 2016 depends on KEXEC_FILE 2017 ---help--- 2018 This option makes kernel signature verification mandatory for 2019 the kexec_file_load() syscall. 2020 2021 In addition to that option, you need to enable signature 2022 verification for the corresponding kernel image type being 2023 loaded in order for this to work. 2024 2025config KEXEC_BZIMAGE_VERIFY_SIG 2026 bool "Enable bzImage signature verification support" 2027 depends on KEXEC_VERIFY_SIG 2028 depends on SIGNED_PE_FILE_VERIFICATION 2029 select SYSTEM_TRUSTED_KEYRING 2030 ---help--- 2031 Enable bzImage signature verification support. 2032 2033config CRASH_DUMP 2034 bool "kernel crash dumps" 2035 depends on X86_64 || (X86_32 && HIGHMEM) 2036 ---help--- 2037 Generate crash dump after being started by kexec. 2038 This should be normally only set in special crash dump kernels 2039 which are loaded in the main kernel with kexec-tools into 2040 a specially reserved region and then later executed after 2041 a crash by kdump/kexec. The crash dump kernel must be compiled 2042 to a memory address not used by the main kernel or BIOS using 2043 PHYSICAL_START, or it must be built as a relocatable image 2044 (CONFIG_RELOCATABLE=y). 2045 For more details see Documentation/kdump/kdump.txt 2046 2047config KEXEC_JUMP 2048 bool "kexec jump" 2049 depends on KEXEC && HIBERNATION 2050 ---help--- 2051 Jump between original kernel and kexeced kernel and invoke 2052 code in physical address mode via KEXEC 2053 2054config PHYSICAL_START 2055 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2056 default "0x1000000" 2057 ---help--- 2058 This gives the physical address where the kernel is loaded. 2059 2060 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2061 bzImage will decompress itself to above physical address and 2062 run from there. Otherwise, bzImage will run from the address where 2063 it has been loaded by the boot loader and will ignore above physical 2064 address. 2065 2066 In normal kdump cases one does not have to set/change this option 2067 as now bzImage can be compiled as a completely relocatable image 2068 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2069 address. This option is mainly useful for the folks who don't want 2070 to use a bzImage for capturing the crash dump and want to use a 2071 vmlinux instead. vmlinux is not relocatable hence a kernel needs 2072 to be specifically compiled to run from a specific memory area 2073 (normally a reserved region) and this option comes handy. 2074 2075 So if you are using bzImage for capturing the crash dump, 2076 leave the value here unchanged to 0x1000000 and set 2077 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2078 for capturing the crash dump change this value to start of 2079 the reserved region. In other words, it can be set based on 2080 the "X" value as specified in the "crashkernel=YM@XM" 2081 command line boot parameter passed to the panic-ed 2082 kernel. Please take a look at Documentation/kdump/kdump.txt 2083 for more details about crash dumps. 2084 2085 Usage of bzImage for capturing the crash dump is recommended as 2086 one does not have to build two kernels. Same kernel can be used 2087 as production kernel and capture kernel. Above option should have 2088 gone away after relocatable bzImage support is introduced. But it 2089 is present because there are users out there who continue to use 2090 vmlinux for dump capture. This option should go away down the 2091 line. 2092 2093 Don't change this unless you know what you are doing. 2094 2095config RELOCATABLE 2096 bool "Build a relocatable kernel" 2097 default y 2098 ---help--- 2099 This builds a kernel image that retains relocation information 2100 so it can be loaded someplace besides the default 1MB. 2101 The relocations tend to make the kernel binary about 10% larger, 2102 but are discarded at runtime. 2103 2104 One use is for the kexec on panic case where the recovery kernel 2105 must live at a different physical address than the primary 2106 kernel. 2107 2108 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2109 it has been loaded at and the compile time physical address 2110 (CONFIG_PHYSICAL_START) is used as the minimum location. 2111 2112config RANDOMIZE_BASE 2113 bool "Randomize the address of the kernel image (KASLR)" 2114 depends on RELOCATABLE 2115 default y 2116 ---help--- 2117 In support of Kernel Address Space Layout Randomization (KASLR), 2118 this randomizes the physical address at which the kernel image 2119 is decompressed and the virtual address where the kernel 2120 image is mapped, as a security feature that deters exploit 2121 attempts relying on knowledge of the location of kernel 2122 code internals. 2123 2124 On 64-bit, the kernel physical and virtual addresses are 2125 randomized separately. The physical address will be anywhere 2126 between 16MB and the top of physical memory (up to 64TB). The 2127 virtual address will be randomized from 16MB up to 1GB (9 bits 2128 of entropy). Note that this also reduces the memory space 2129 available to kernel modules from 1.5GB to 1GB. 2130 2131 On 32-bit, the kernel physical and virtual addresses are 2132 randomized together. They will be randomized from 16MB up to 2133 512MB (8 bits of entropy). 2134 2135 Entropy is generated using the RDRAND instruction if it is 2136 supported. If RDTSC is supported, its value is mixed into 2137 the entropy pool as well. If neither RDRAND nor RDTSC are 2138 supported, then entropy is read from the i8254 timer. The 2139 usable entropy is limited by the kernel being built using 2140 2GB addressing, and that PHYSICAL_ALIGN must be at a 2141 minimum of 2MB. As a result, only 10 bits of entropy are 2142 theoretically possible, but the implementations are further 2143 limited due to memory layouts. 2144 2145 If unsure, say Y. 2146 2147# Relocation on x86 needs some additional build support 2148config X86_NEED_RELOCS 2149 def_bool y 2150 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2151 2152config PHYSICAL_ALIGN 2153 hex "Alignment value to which kernel should be aligned" 2154 default "0x200000" 2155 range 0x2000 0x1000000 if X86_32 2156 range 0x200000 0x1000000 if X86_64 2157 ---help--- 2158 This value puts the alignment restrictions on physical address 2159 where kernel is loaded and run from. Kernel is compiled for an 2160 address which meets above alignment restriction. 2161 2162 If bootloader loads the kernel at a non-aligned address and 2163 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2164 address aligned to above value and run from there. 2165 2166 If bootloader loads the kernel at a non-aligned address and 2167 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2168 load address and decompress itself to the address it has been 2169 compiled for and run from there. The address for which kernel is 2170 compiled already meets above alignment restrictions. Hence the 2171 end result is that kernel runs from a physical address meeting 2172 above alignment restrictions. 2173 2174 On 32-bit this value must be a multiple of 0x2000. On 64-bit 2175 this value must be a multiple of 0x200000. 2176 2177 Don't change this unless you know what you are doing. 2178 2179config DYNAMIC_MEMORY_LAYOUT 2180 bool 2181 ---help--- 2182 This option makes base addresses of vmalloc and vmemmap as well as 2183 __PAGE_OFFSET movable during boot. 2184 2185config RANDOMIZE_MEMORY 2186 bool "Randomize the kernel memory sections" 2187 depends on X86_64 2188 depends on RANDOMIZE_BASE 2189 select DYNAMIC_MEMORY_LAYOUT 2190 default RANDOMIZE_BASE 2191 ---help--- 2192 Randomizes the base virtual address of kernel memory sections 2193 (physical memory mapping, vmalloc & vmemmap). This security feature 2194 makes exploits relying on predictable memory locations less reliable. 2195 2196 The order of allocations remains unchanged. Entropy is generated in 2197 the same way as RANDOMIZE_BASE. Current implementation in the optimal 2198 configuration have in average 30,000 different possible virtual 2199 addresses for each memory section. 2200 2201 If unsure, say Y. 2202 2203config RANDOMIZE_MEMORY_PHYSICAL_PADDING 2204 hex "Physical memory mapping padding" if EXPERT 2205 depends on RANDOMIZE_MEMORY 2206 default "0xa" if MEMORY_HOTPLUG 2207 default "0x0" 2208 range 0x1 0x40 if MEMORY_HOTPLUG 2209 range 0x0 0x40 2210 ---help--- 2211 Define the padding in terabytes added to the existing physical 2212 memory size during kernel memory randomization. It is useful 2213 for memory hotplug support but reduces the entropy available for 2214 address randomization. 2215 2216 If unsure, leave at the default value. 2217 2218config HOTPLUG_CPU 2219 bool "Support for hot-pluggable CPUs" 2220 depends on SMP 2221 ---help--- 2222 Say Y here to allow turning CPUs off and on. CPUs can be 2223 controlled through /sys/devices/system/cpu. 2224 ( Note: power management support will enable this option 2225 automatically on SMP systems. ) 2226 Say N if you want to disable CPU hotplug. 2227 2228config BOOTPARAM_HOTPLUG_CPU0 2229 bool "Set default setting of cpu0_hotpluggable" 2230 depends on HOTPLUG_CPU 2231 ---help--- 2232 Set whether default state of cpu0_hotpluggable is on or off. 2233 2234 Say Y here to enable CPU0 hotplug by default. If this switch 2235 is turned on, there is no need to give cpu0_hotplug kernel 2236 parameter and the CPU0 hotplug feature is enabled by default. 2237 2238 Please note: there are two known CPU0 dependencies if you want 2239 to enable the CPU0 hotplug feature either by this switch or by 2240 cpu0_hotplug kernel parameter. 2241 2242 First, resume from hibernate or suspend always starts from CPU0. 2243 So hibernate and suspend are prevented if CPU0 is offline. 2244 2245 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 2246 offline if any interrupt can not migrate out of CPU0. There may 2247 be other CPU0 dependencies. 2248 2249 Please make sure the dependencies are under your control before 2250 you enable this feature. 2251 2252 Say N if you don't want to enable CPU0 hotplug feature by default. 2253 You still can enable the CPU0 hotplug feature at boot by kernel 2254 parameter cpu0_hotplug. 2255 2256config DEBUG_HOTPLUG_CPU0 2257 def_bool n 2258 prompt "Debug CPU0 hotplug" 2259 depends on HOTPLUG_CPU 2260 ---help--- 2261 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2262 soon as possible and boots up userspace with CPU0 offlined. User 2263 can online CPU0 back after boot time. 2264 2265 To debug CPU0 hotplug, you need to enable CPU0 offline/online 2266 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2267 compilation or giving cpu0_hotplug kernel parameter at boot. 2268 2269 If unsure, say N. 2270 2271config COMPAT_VDSO 2272 def_bool n 2273 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2274 depends on COMPAT_32 2275 ---help--- 2276 Certain buggy versions of glibc will crash if they are 2277 presented with a 32-bit vDSO that is not mapped at the address 2278 indicated in its segment table. 2279 2280 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2281 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2282 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2283 the only released version with the bug, but OpenSUSE 9 2284 contains a buggy "glibc 2.3.2". 2285 2286 The symptom of the bug is that everything crashes on startup, saying: 2287 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2288 2289 Saying Y here changes the default value of the vdso32 boot 2290 option from 1 to 0, which turns off the 32-bit vDSO entirely. 2291 This works around the glibc bug but hurts performance. 2292 2293 If unsure, say N: if you are compiling your own kernel, you 2294 are unlikely to be using a buggy version of glibc. 2295 2296choice 2297 prompt "vsyscall table for legacy applications" 2298 depends on X86_64 2299 default LEGACY_VSYSCALL_EMULATE 2300 help 2301 Legacy user code that does not know how to find the vDSO expects 2302 to be able to issue three syscalls by calling fixed addresses in 2303 kernel space. Since this location is not randomized with ASLR, 2304 it can be used to assist security vulnerability exploitation. 2305 2306 This setting can be changed at boot time via the kernel command 2307 line parameter vsyscall=[emulate|none]. 2308 2309 On a system with recent enough glibc (2.14 or newer) and no 2310 static binaries, you can say None without a performance penalty 2311 to improve security. 2312 2313 If unsure, select "Emulate". 2314 2315 config LEGACY_VSYSCALL_EMULATE 2316 bool "Emulate" 2317 help 2318 The kernel traps and emulates calls into the fixed 2319 vsyscall address mapping. This makes the mapping 2320 non-executable, but it still contains known contents, 2321 which could be used in certain rare security vulnerability 2322 exploits. This configuration is recommended when userspace 2323 still uses the vsyscall area. 2324 2325 config LEGACY_VSYSCALL_NONE 2326 bool "None" 2327 help 2328 There will be no vsyscall mapping at all. This will 2329 eliminate any risk of ASLR bypass due to the vsyscall 2330 fixed address mapping. Attempts to use the vsyscalls 2331 will be reported to dmesg, so that either old or 2332 malicious userspace programs can be identified. 2333 2334endchoice 2335 2336config CMDLINE_BOOL 2337 bool "Built-in kernel command line" 2338 ---help--- 2339 Allow for specifying boot arguments to the kernel at 2340 build time. On some systems (e.g. embedded ones), it is 2341 necessary or convenient to provide some or all of the 2342 kernel boot arguments with the kernel itself (that is, 2343 to not rely on the boot loader to provide them.) 2344 2345 To compile command line arguments into the kernel, 2346 set this option to 'Y', then fill in the 2347 boot arguments in CONFIG_CMDLINE. 2348 2349 Systems with fully functional boot loaders (i.e. non-embedded) 2350 should leave this option set to 'N'. 2351 2352config CMDLINE 2353 string "Built-in kernel command string" 2354 depends on CMDLINE_BOOL 2355 default "" 2356 ---help--- 2357 Enter arguments here that should be compiled into the kernel 2358 image and used at boot time. If the boot loader provides a 2359 command line at boot time, it is appended to this string to 2360 form the full kernel command line, when the system boots. 2361 2362 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2363 change this behavior. 2364 2365 In most cases, the command line (whether built-in or provided 2366 by the boot loader) should specify the device for the root 2367 file system. 2368 2369config CMDLINE_OVERRIDE 2370 bool "Built-in command line overrides boot loader arguments" 2371 depends on CMDLINE_BOOL 2372 ---help--- 2373 Set this option to 'Y' to have the kernel ignore the boot loader 2374 command line, and use ONLY the built-in command line. 2375 2376 This is used to work around broken boot loaders. This should 2377 be set to 'N' under normal conditions. 2378 2379config MODIFY_LDT_SYSCALL 2380 bool "Enable the LDT (local descriptor table)" if EXPERT 2381 default y 2382 ---help--- 2383 Linux can allow user programs to install a per-process x86 2384 Local Descriptor Table (LDT) using the modify_ldt(2) system 2385 call. This is required to run 16-bit or segmented code such as 2386 DOSEMU or some Wine programs. It is also used by some very old 2387 threading libraries. 2388 2389 Enabling this feature adds a small amount of overhead to 2390 context switches and increases the low-level kernel attack 2391 surface. Disabling it removes the modify_ldt(2) system call. 2392 2393 Saying 'N' here may make sense for embedded or server kernels. 2394 2395source "kernel/livepatch/Kconfig" 2396 2397endmenu 2398 2399config ARCH_HAS_ADD_PAGES 2400 def_bool y 2401 depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 2402 2403config ARCH_ENABLE_MEMORY_HOTPLUG 2404 def_bool y 2405 depends on X86_64 || (X86_32 && HIGHMEM) 2406 2407config ARCH_ENABLE_MEMORY_HOTREMOVE 2408 def_bool y 2409 depends on MEMORY_HOTPLUG 2410 2411config USE_PERCPU_NUMA_NODE_ID 2412 def_bool y 2413 depends on NUMA 2414 2415config ARCH_ENABLE_SPLIT_PMD_PTLOCK 2416 def_bool y 2417 depends on X86_64 || X86_PAE 2418 2419config ARCH_ENABLE_HUGEPAGE_MIGRATION 2420 def_bool y 2421 depends on X86_64 && HUGETLB_PAGE && MIGRATION 2422 2423config ARCH_ENABLE_THP_MIGRATION 2424 def_bool y 2425 depends on X86_64 && TRANSPARENT_HUGEPAGE 2426 2427menu "Power management and ACPI options" 2428 2429config ARCH_HIBERNATION_HEADER 2430 def_bool y 2431 depends on HIBERNATION 2432 2433source "kernel/power/Kconfig" 2434 2435source "drivers/acpi/Kconfig" 2436 2437source "drivers/sfi/Kconfig" 2438 2439config X86_APM_BOOT 2440 def_bool y 2441 depends on APM 2442 2443menuconfig APM 2444 tristate "APM (Advanced Power Management) BIOS support" 2445 depends on X86_32 && PM_SLEEP 2446 ---help--- 2447 APM is a BIOS specification for saving power using several different 2448 techniques. This is mostly useful for battery powered laptops with 2449 APM compliant BIOSes. If you say Y here, the system time will be 2450 reset after a RESUME operation, the /proc/apm device will provide 2451 battery status information, and user-space programs will receive 2452 notification of APM "events" (e.g. battery status change). 2453 2454 If you select "Y" here, you can disable actual use of the APM 2455 BIOS by passing the "apm=off" option to the kernel at boot time. 2456 2457 Note that the APM support is almost completely disabled for 2458 machines with more than one CPU. 2459 2460 In order to use APM, you will need supporting software. For location 2461 and more information, read <file:Documentation/power/apm-acpi.txt> 2462 and the Battery Powered Linux mini-HOWTO, available from 2463 <http://www.tldp.org/docs.html#howto>. 2464 2465 This driver does not spin down disk drives (see the hdparm(8) 2466 manpage ("man 8 hdparm") for that), and it doesn't turn off 2467 VESA-compliant "green" monitors. 2468 2469 This driver does not support the TI 4000M TravelMate and the ACER 2470 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2471 desktop machines also don't have compliant BIOSes, and this driver 2472 may cause those machines to panic during the boot phase. 2473 2474 Generally, if you don't have a battery in your machine, there isn't 2475 much point in using this driver and you should say N. If you get 2476 random kernel OOPSes or reboots that don't seem to be related to 2477 anything, try disabling/enabling this option (or disabling/enabling 2478 APM in your BIOS). 2479 2480 Some other things you should try when experiencing seemingly random, 2481 "weird" problems: 2482 2483 1) make sure that you have enough swap space and that it is 2484 enabled. 2485 2) pass the "no-hlt" option to the kernel 2486 3) switch on floating point emulation in the kernel and pass 2487 the "no387" option to the kernel 2488 4) pass the "floppy=nodma" option to the kernel 2489 5) pass the "mem=4M" option to the kernel (thereby disabling 2490 all but the first 4 MB of RAM) 2491 6) make sure that the CPU is not over clocked. 2492 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2493 8) disable the cache from your BIOS settings 2494 9) install a fan for the video card or exchange video RAM 2495 10) install a better fan for the CPU 2496 11) exchange RAM chips 2497 12) exchange the motherboard. 2498 2499 To compile this driver as a module, choose M here: the 2500 module will be called apm. 2501 2502if APM 2503 2504config APM_IGNORE_USER_SUSPEND 2505 bool "Ignore USER SUSPEND" 2506 ---help--- 2507 This option will ignore USER SUSPEND requests. On machines with a 2508 compliant APM BIOS, you want to say N. However, on the NEC Versa M 2509 series notebooks, it is necessary to say Y because of a BIOS bug. 2510 2511config APM_DO_ENABLE 2512 bool "Enable PM at boot time" 2513 ---help--- 2514 Enable APM features at boot time. From page 36 of the APM BIOS 2515 specification: "When disabled, the APM BIOS does not automatically 2516 power manage devices, enter the Standby State, enter the Suspend 2517 State, or take power saving steps in response to CPU Idle calls." 2518 This driver will make CPU Idle calls when Linux is idle (unless this 2519 feature is turned off -- see "Do CPU IDLE calls", below). This 2520 should always save battery power, but more complicated APM features 2521 will be dependent on your BIOS implementation. You may need to turn 2522 this option off if your computer hangs at boot time when using APM 2523 support, or if it beeps continuously instead of suspending. Turn 2524 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2525 T400CDT. This is off by default since most machines do fine without 2526 this feature. 2527 2528config APM_CPU_IDLE 2529 depends on CPU_IDLE 2530 bool "Make CPU Idle calls when idle" 2531 ---help--- 2532 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2533 On some machines, this can activate improved power savings, such as 2534 a slowed CPU clock rate, when the machine is idle. These idle calls 2535 are made after the idle loop has run for some length of time (e.g., 2536 333 mS). On some machines, this will cause a hang at boot time or 2537 whenever the CPU becomes idle. (On machines with more than one CPU, 2538 this option does nothing.) 2539 2540config APM_DISPLAY_BLANK 2541 bool "Enable console blanking using APM" 2542 ---help--- 2543 Enable console blanking using the APM. Some laptops can use this to 2544 turn off the LCD backlight when the screen blanker of the Linux 2545 virtual console blanks the screen. Note that this is only used by 2546 the virtual console screen blanker, and won't turn off the backlight 2547 when using the X Window system. This also doesn't have anything to 2548 do with your VESA-compliant power-saving monitor. Further, this 2549 option doesn't work for all laptops -- it might not turn off your 2550 backlight at all, or it might print a lot of errors to the console, 2551 especially if you are using gpm. 2552 2553config APM_ALLOW_INTS 2554 bool "Allow interrupts during APM BIOS calls" 2555 ---help--- 2556 Normally we disable external interrupts while we are making calls to 2557 the APM BIOS as a measure to lessen the effects of a badly behaving 2558 BIOS implementation. The BIOS should reenable interrupts if it 2559 needs to. Unfortunately, some BIOSes do not -- especially those in 2560 many of the newer IBM Thinkpads. If you experience hangs when you 2561 suspend, try setting this to Y. Otherwise, say N. 2562 2563endif # APM 2564 2565source "drivers/cpufreq/Kconfig" 2566 2567source "drivers/cpuidle/Kconfig" 2568 2569source "drivers/idle/Kconfig" 2570 2571endmenu 2572 2573 2574menu "Bus options (PCI etc.)" 2575 2576config PCI 2577 bool "PCI support" 2578 default y 2579 ---help--- 2580 Find out whether you have a PCI motherboard. PCI is the name of a 2581 bus system, i.e. the way the CPU talks to the other stuff inside 2582 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2583 VESA. If you have PCI, say Y, otherwise N. 2584 2585choice 2586 prompt "PCI access mode" 2587 depends on X86_32 && PCI 2588 default PCI_GOANY 2589 ---help--- 2590 On PCI systems, the BIOS can be used to detect the PCI devices and 2591 determine their configuration. However, some old PCI motherboards 2592 have BIOS bugs and may crash if this is done. Also, some embedded 2593 PCI-based systems don't have any BIOS at all. Linux can also try to 2594 detect the PCI hardware directly without using the BIOS. 2595 2596 With this option, you can specify how Linux should detect the 2597 PCI devices. If you choose "BIOS", the BIOS will be used, 2598 if you choose "Direct", the BIOS won't be used, and if you 2599 choose "MMConfig", then PCI Express MMCONFIG will be used. 2600 If you choose "Any", the kernel will try MMCONFIG, then the 2601 direct access method and falls back to the BIOS if that doesn't 2602 work. If unsure, go with the default, which is "Any". 2603 2604config PCI_GOBIOS 2605 bool "BIOS" 2606 2607config PCI_GOMMCONFIG 2608 bool "MMConfig" 2609 2610config PCI_GODIRECT 2611 bool "Direct" 2612 2613config PCI_GOOLPC 2614 bool "OLPC XO-1" 2615 depends on OLPC 2616 2617config PCI_GOANY 2618 bool "Any" 2619 2620endchoice 2621 2622config PCI_BIOS 2623 def_bool y 2624 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2625 2626# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2627config PCI_DIRECT 2628 def_bool y 2629 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2630 2631config PCI_MMCONFIG 2632 bool "Support mmconfig PCI config space access" if X86_64 2633 default y 2634 depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST) 2635 depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) 2636 2637config PCI_OLPC 2638 def_bool y 2639 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2640 2641config PCI_XEN 2642 def_bool y 2643 depends on PCI && XEN 2644 select SWIOTLB_XEN 2645 2646config PCI_DOMAINS 2647 def_bool y 2648 depends on PCI 2649 2650config MMCONF_FAM10H 2651 def_bool y 2652 depends on X86_64 && PCI_MMCONFIG && ACPI 2653 2654config PCI_CNB20LE_QUIRK 2655 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2656 depends on PCI 2657 help 2658 Read the PCI windows out of the CNB20LE host bridge. This allows 2659 PCI hotplug to work on systems with the CNB20LE chipset which do 2660 not have ACPI. 2661 2662 There's no public spec for this chipset, and this functionality 2663 is known to be incomplete. 2664 2665 You should say N unless you know you need this. 2666 2667source "drivers/pci/Kconfig" 2668 2669config ISA_BUS 2670 bool "ISA bus support on modern systems" if EXPERT 2671 help 2672 Expose ISA bus device drivers and options available for selection and 2673 configuration. Enable this option if your target machine has an ISA 2674 bus. ISA is an older system, displaced by PCI and newer bus 2675 architectures -- if your target machine is modern, it probably does 2676 not have an ISA bus. 2677 2678 If unsure, say N. 2679 2680# x86_64 have no ISA slots, but can have ISA-style DMA. 2681config ISA_DMA_API 2682 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2683 default y 2684 help 2685 Enables ISA-style DMA support for devices requiring such controllers. 2686 If unsure, say Y. 2687 2688if X86_32 2689 2690config ISA 2691 bool "ISA support" 2692 ---help--- 2693 Find out whether you have ISA slots on your motherboard. ISA is the 2694 name of a bus system, i.e. the way the CPU talks to the other stuff 2695 inside your box. Other bus systems are PCI, EISA, MicroChannel 2696 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2697 newer boards don't support it. If you have ISA, say Y, otherwise N. 2698 2699config EISA 2700 bool "EISA support" 2701 depends on ISA 2702 ---help--- 2703 The Extended Industry Standard Architecture (EISA) bus was 2704 developed as an open alternative to the IBM MicroChannel bus. 2705 2706 The EISA bus provided some of the features of the IBM MicroChannel 2707 bus while maintaining backward compatibility with cards made for 2708 the older ISA bus. The EISA bus saw limited use between 1988 and 2709 1995 when it was made obsolete by the PCI bus. 2710 2711 Say Y here if you are building a kernel for an EISA-based machine. 2712 2713 Otherwise, say N. 2714 2715source "drivers/eisa/Kconfig" 2716 2717config SCx200 2718 tristate "NatSemi SCx200 support" 2719 ---help--- 2720 This provides basic support for National Semiconductor's 2721 (now AMD's) Geode processors. The driver probes for the 2722 PCI-IDs of several on-chip devices, so its a good dependency 2723 for other scx200_* drivers. 2724 2725 If compiled as a module, the driver is named scx200. 2726 2727config SCx200HR_TIMER 2728 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2729 depends on SCx200 2730 default y 2731 ---help--- 2732 This driver provides a clocksource built upon the on-chip 2733 27MHz high-resolution timer. Its also a workaround for 2734 NSC Geode SC-1100's buggy TSC, which loses time when the 2735 processor goes idle (as is done by the scheduler). The 2736 other workaround is idle=poll boot option. 2737 2738config OLPC 2739 bool "One Laptop Per Child support" 2740 depends on !X86_PAE 2741 select GPIOLIB 2742 select OF 2743 select OF_PROMTREE 2744 select IRQ_DOMAIN 2745 ---help--- 2746 Add support for detecting the unique features of the OLPC 2747 XO hardware. 2748 2749config OLPC_XO1_PM 2750 bool "OLPC XO-1 Power Management" 2751 depends on OLPC && MFD_CS5535=y && PM_SLEEP 2752 ---help--- 2753 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2754 2755config OLPC_XO1_RTC 2756 bool "OLPC XO-1 Real Time Clock" 2757 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2758 ---help--- 2759 Add support for the XO-1 real time clock, which can be used as a 2760 programmable wakeup source. 2761 2762config OLPC_XO1_SCI 2763 bool "OLPC XO-1 SCI extras" 2764 depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2765 depends on INPUT=y 2766 select POWER_SUPPLY 2767 ---help--- 2768 Add support for SCI-based features of the OLPC XO-1 laptop: 2769 - EC-driven system wakeups 2770 - Power button 2771 - Ebook switch 2772 - Lid switch 2773 - AC adapter status updates 2774 - Battery status updates 2775 2776config OLPC_XO15_SCI 2777 bool "OLPC XO-1.5 SCI extras" 2778 depends on OLPC && ACPI 2779 select POWER_SUPPLY 2780 ---help--- 2781 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2782 - EC-driven system wakeups 2783 - AC adapter status updates 2784 - Battery status updates 2785 2786config ALIX 2787 bool "PCEngines ALIX System Support (LED setup)" 2788 select GPIOLIB 2789 ---help--- 2790 This option enables system support for the PCEngines ALIX. 2791 At present this just sets up LEDs for GPIO control on 2792 ALIX2/3/6 boards. However, other system specific setup should 2793 get added here. 2794 2795 Note: You must still enable the drivers for GPIO and LED support 2796 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2797 2798 Note: You have to set alix.force=1 for boards with Award BIOS. 2799 2800config NET5501 2801 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2802 select GPIOLIB 2803 ---help--- 2804 This option enables system support for the Soekris Engineering net5501. 2805 2806config GEOS 2807 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2808 select GPIOLIB 2809 depends on DMI 2810 ---help--- 2811 This option enables system support for the Traverse Technologies GEOS. 2812 2813config TS5500 2814 bool "Technologic Systems TS-5500 platform support" 2815 depends on MELAN 2816 select CHECK_SIGNATURE 2817 select NEW_LEDS 2818 select LEDS_CLASS 2819 ---help--- 2820 This option enables system support for the Technologic Systems TS-5500. 2821 2822endif # X86_32 2823 2824config AMD_NB 2825 def_bool y 2826 depends on CPU_SUP_AMD && PCI 2827 2828source "drivers/pcmcia/Kconfig" 2829 2830config RAPIDIO 2831 tristate "RapidIO support" 2832 depends on PCI 2833 help 2834 If enabled this option will include drivers and the core 2835 infrastructure code to support RapidIO interconnect devices. 2836 2837source "drivers/rapidio/Kconfig" 2838 2839config X86_SYSFB 2840 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2841 help 2842 Firmwares often provide initial graphics framebuffers so the BIOS, 2843 bootloader or kernel can show basic video-output during boot for 2844 user-guidance and debugging. Historically, x86 used the VESA BIOS 2845 Extensions and EFI-framebuffers for this, which are mostly limited 2846 to x86. 2847 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2848 framebuffers so the new generic system-framebuffer drivers can be 2849 used on x86. If the framebuffer is not compatible with the generic 2850 modes, it is advertised as fallback platform framebuffer so legacy 2851 drivers like efifb, vesafb and uvesafb can pick it up. 2852 If this option is not selected, all system framebuffers are always 2853 marked as fallback platform framebuffers as usual. 2854 2855 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2856 not be able to pick up generic system framebuffers if this option 2857 is selected. You are highly encouraged to enable simplefb as 2858 replacement if you select this option. simplefb can correctly deal 2859 with generic system framebuffers. But you should still keep vesafb 2860 and others enabled as fallback if a system framebuffer is 2861 incompatible with simplefb. 2862 2863 If unsure, say Y. 2864 2865endmenu 2866 2867 2868menu "Binary Emulations" 2869 2870config IA32_EMULATION 2871 bool "IA32 Emulation" 2872 depends on X86_64 2873 select ARCH_WANT_OLD_COMPAT_IPC 2874 select BINFMT_ELF 2875 select COMPAT_BINFMT_ELF 2876 select COMPAT_OLD_SIGACTION 2877 ---help--- 2878 Include code to run legacy 32-bit programs under a 2879 64-bit kernel. You should likely turn this on, unless you're 2880 100% sure that you don't have any 32-bit programs left. 2881 2882config IA32_AOUT 2883 tristate "IA32 a.out support" 2884 depends on IA32_EMULATION 2885 ---help--- 2886 Support old a.out binaries in the 32bit emulation. 2887 2888config X86_X32 2889 bool "x32 ABI for 64-bit mode" 2890 depends on X86_64 2891 ---help--- 2892 Include code to run binaries for the x32 native 32-bit ABI 2893 for 64-bit processors. An x32 process gets access to the 2894 full 64-bit register file and wide data path while leaving 2895 pointers at 32 bits for smaller memory footprint. 2896 2897 You will need a recent binutils (2.22 or later) with 2898 elf32_x86_64 support enabled to compile a kernel with this 2899 option set. 2900 2901config COMPAT_32 2902 def_bool y 2903 depends on IA32_EMULATION || X86_32 2904 select HAVE_UID16 2905 select OLD_SIGSUSPEND3 2906 2907config COMPAT 2908 def_bool y 2909 depends on IA32_EMULATION || X86_X32 2910 2911if COMPAT 2912config COMPAT_FOR_U64_ALIGNMENT 2913 def_bool y 2914 2915config SYSVIPC_COMPAT 2916 def_bool y 2917 depends on SYSVIPC 2918endif 2919 2920endmenu 2921 2922 2923config HAVE_ATOMIC_IOMAP 2924 def_bool y 2925 depends on X86_32 2926 2927config X86_DEV_DMA_OPS 2928 bool 2929 depends on X86_64 || STA2X11 2930 2931config X86_DMA_REMAP 2932 bool 2933 depends on STA2X11 2934 2935config HAVE_GENERIC_GUP 2936 def_bool y 2937 2938source "drivers/firmware/Kconfig" 2939 2940source "arch/x86/kvm/Kconfig" 2941