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