1daa93fabSSam Ravnborg# Select 32 or 64 bit 2daa93fabSSam Ravnborgconfig 64BIT 36840999bSSam Ravnborg bool "64-bit kernel" if ARCH = "x86" 4ffee0de4SDavid Woodhouse default ARCH != "i386" 58f9ca475SIngo Molnar ---help--- 6daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 7daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 8daa93fabSSam Ravnborg 9daa93fabSSam Ravnborgconfig X86_32 103120e25eSJan Beulich def_bool y 113120e25eSJan Beulich depends on !64BIT 12daa93fabSSam Ravnborg 13daa93fabSSam Ravnborgconfig X86_64 143120e25eSJan Beulich def_bool y 153120e25eSJan Beulich depends on 64BIT 161032c0baSSam Ravnborg 171032c0baSSam Ravnborg### Arch settings 188d5fffb9SSam Ravnborgconfig X86 193c2362e6SHarvey Harrison def_bool y 206471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 216e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 226471b825SIngo Molnar select ANON_INODES 236471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 246471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 256471b825SIngo Molnar select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 26446f24d1SStephen Boyd select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 2721266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 286471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 2972d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 30957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 3196601adbSDan Williams select ARCH_HAS_PMEM_API if X86_64 3267a3e8feSRoss Zwisler select ARCH_HAS_MMIO_FLUSH 336471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 34c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 356471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 366471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 3777fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 385e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 396471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 403b242c66SMel Gorman select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 41be5e610cSPeter Zijlstra select ARCH_SUPPORTS_INT128 if X86_64 426471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 436471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 446471b825SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF if X86_64 456471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 466471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 4772b252aeSMel Gorman select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 485aaeb5c0SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 49da4276b8SIngo Molnar select ARCH_WANT_FRAME_POINTERS 506471b825SIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION if X86_32 516471b825SIngo Molnar select ARCH_WANT_OPTIONAL_GPIOLIB 526471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 536471b825SIngo Molnar select CLKEVT_I8253 546471b825SIngo Molnar select CLKSRC_I8253 if X86_32 556471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 566471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 576471b825SIngo Molnar select CLONE_BACKWARDS if X86_32 586471b825SIngo Molnar select COMPAT_OLD_SIGACTION if IA32_EMULATION 596471b825SIngo Molnar select DCACHE_WORD_ACCESS 6045471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 6145471cd9SLinus Torvalds select EDAC_SUPPORT 626471b825SIngo Molnar select GENERIC_CLOCKEVENTS 636471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 646471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 656471b825SIngo Molnar select GENERIC_CMOS_UPDATE 666471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 676471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 686471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 696471b825SIngo Molnar select GENERIC_IOMAP 706471b825SIngo Molnar select GENERIC_IRQ_PROBE 716471b825SIngo Molnar select GENERIC_IRQ_SHOW 726471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 736471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 746471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 756471b825SIngo Molnar select GENERIC_STRNLEN_USER 766471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 776471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 786471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 796471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 806471b825SIngo Molnar select HAVE_AOUT if X86_32 816471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 826471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 836471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 846471b825SIngo Molnar select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 856471b825SIngo Molnar select HAVE_ARCH_KGDB 866471b825SIngo Molnar select HAVE_ARCH_KMEMCHECK 879e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 889e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 896471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 906471b825SIngo Molnar select HAVE_ARCH_SOFT_DIRTY if X86_64 916471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 926471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 936471b825SIngo Molnar select HAVE_BPF_JIT if X86_64 946471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 956471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 966471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 976471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 98c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 996471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1006471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1016471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1026471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1039c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 104677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 10506aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 10658340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1076471b825SIngo Molnar select HAVE_FENTRY if X86_64 1086471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1096471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_FP_TEST 1106471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1116471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1126471b825SIngo Molnar select HAVE_GENERIC_DMA_COHERENT if X86_32 1130067f129SK.Prasad select HAVE_HW_BREAKPOINT 1146471b825SIngo Molnar select HAVE_IDE 1156471b825SIngo Molnar select HAVE_IOREMAP_PROT 1166471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1176471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1186471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1196471b825SIngo Molnar select HAVE_KERNEL_GZIP 1206471b825SIngo Molnar select HAVE_KERNEL_LZ4 1216471b825SIngo Molnar select HAVE_KERNEL_LZMA 1226471b825SIngo Molnar select HAVE_KERNEL_LZO 1236471b825SIngo Molnar select HAVE_KERNEL_XZ 1246471b825SIngo Molnar select HAVE_KPROBES 1256471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 1266471b825SIngo Molnar select HAVE_KRETPROBES 1276471b825SIngo Molnar select HAVE_KVM 1286471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1296471b825SIngo Molnar select HAVE_MEMBLOCK 1306471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1310102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 1326471b825SIngo Molnar select HAVE_OPROFILE 1336471b825SIngo Molnar select HAVE_OPTPROBES 1346471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1356471b825SIngo Molnar select HAVE_PERF_EVENTS 136c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 137c5e63197SJiri Olsa select HAVE_PERF_REGS 138c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1396471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 1406471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1410c3619eaSBrian Gerst select HAVE_UID16 if X86_32 || IA32_EMULATION 1426471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1437c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 144c0185808SThomas Gleixner select IRQ_FORCED_THREADING 145786d35d4SDavid Howells select MODULES_USE_ELF_RELA if X86_64 1466471b825SIngo Molnar select MODULES_USE_ELF_REL if X86_32 1475b3eb3adSAl Viro select OLD_SIGACTION if X86_32 1486471b825SIngo Molnar select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 1496471b825SIngo Molnar select PERF_EVENTS 1503195ef59SPrarit Bhargava select RTC_LIB 1516471b825SIngo Molnar select SPARSE_IRQ 15283fe27eaSPranith Kumar select SRCU 1536471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 1546471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1556471b825SIngo Molnar select VIRT_TO_BUS 1566471b825SIngo Molnar select X86_DEV_DMA_OPS if X86_64 1576471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1587d8330a5SBalbir Singh 159ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1603120e25eSJan Beulich def_bool y 1613120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 162ba7e4d13SIngo Molnar 16351b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 16451b26adaSLinus Torvalds string 16551b26adaSLinus Torvalds default "elf32-i386" if X86_32 16651b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 16751b26adaSLinus Torvalds 16873531905SSam Ravnborgconfig ARCH_DEFCONFIG 169b9b39bfbSSam Ravnborg string 17073531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 17173531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 172b9b39bfbSSam Ravnborg 1738d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 1743c2362e6SHarvey Harrison def_bool y 1758d5fffb9SSam Ravnborg 1768d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 1773c2362e6SHarvey Harrison def_bool y 1788d5fffb9SSam Ravnborg 1798d5fffb9SSam Ravnborgconfig MMU 1803c2362e6SHarvey Harrison def_bool y 1818d5fffb9SSam Ravnborg 1829e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 1839e08f57dSDaniel Cashman default 28 if 64BIT 1849e08f57dSDaniel Cashman default 8 1859e08f57dSDaniel Cashman 1869e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 1879e08f57dSDaniel Cashman default 32 if 64BIT 1889e08f57dSDaniel Cashman default 16 1899e08f57dSDaniel Cashman 1909e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 1919e08f57dSDaniel Cashman default 8 1929e08f57dSDaniel Cashman 1939e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 1949e08f57dSDaniel Cashman default 16 1959e08f57dSDaniel Cashman 1968d5fffb9SSam Ravnborgconfig SBUS 1978d5fffb9SSam Ravnborg bool 1988d5fffb9SSam Ravnborg 1993bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2003120e25eSJan Beulich def_bool y 201a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2023bc4e459SFUJITA Tomonori 20318e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2044a14d84eSAndrew Morton def_bool y 20518e98307SFUJITA Tomonori 2068d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2073120e25eSJan Beulich def_bool y 2083120e25eSJan Beulich depends on ISA_DMA_API 2098d5fffb9SSam Ravnborg 2108d5fffb9SSam Ravnborgconfig GENERIC_BUG 2113c2362e6SHarvey Harrison def_bool y 2128d5fffb9SSam Ravnborg depends on BUG 213b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 214b93a531eSJan Beulich 215b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 216b93a531eSJan Beulich bool 2178d5fffb9SSam Ravnborg 2188d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2193c2362e6SHarvey Harrison def_bool y 2208d5fffb9SSam Ravnborg 2218d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2223120e25eSJan Beulich def_bool y 2233120e25eSJan Beulich depends on ISA_DMA_API 2248d5fffb9SSam Ravnborg 2251032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2263120e25eSJan Beulich def_bool y 2271032c0baSSam Ravnborg 2281032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2291032c0baSSam Ravnborg def_bool y 2301032c0baSSam Ravnborg 2319a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2329a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2338d5fffb9SSam Ravnborg 2341b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2351b27d05bSPekka Enberg def_bool y 2361b27d05bSPekka Enberg 237dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 23889c9c4c5SBrian Gerst def_bool y 239b32ef636Stravis@sgi.com 24008fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 24108fc4580STejun Heo def_bool y 24208fc4580STejun Heo 24308fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 24411124411STejun Heo def_bool y 24511124411STejun Heo 246801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 247801e4062SJohannes Berg def_bool y 248801e4062SJohannes Berg 249f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 250f4cb5700SJohannes Berg def_bool y 251f4cb5700SJohannes Berg 252cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 253cfe28c5dSSteve Capper def_bool y 254cfe28c5dSSteve Capper 25553313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 25653313b2cSSteve Capper def_bool y 25753313b2cSSteve Capper 2588d5fffb9SSam Ravnborgconfig ZONE_DMA32 259e0fd24a3SJan Beulich def_bool y if X86_64 2608d5fffb9SSam Ravnborg 2618d5fffb9SSam Ravnborgconfig AUDIT_ARCH 262e0fd24a3SJan Beulich def_bool y if X86_64 2638d5fffb9SSam Ravnborg 264765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 265765c68bdSIngo Molnar def_bool y 266765c68bdSIngo Molnar 2676a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 2686a11f75bSAkinobu Mita def_bool y 2696a11f75bSAkinobu Mita 270d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 271d6f2d75aSAndrey Ryabinin hex 272d6f2d75aSAndrey Ryabinin depends on KASAN 273d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 274d6f2d75aSAndrey Ryabinin 27569575d38SShane Wangconfig HAVE_INTEL_TXT 27669575d38SShane Wang def_bool y 2776ea30386SKees Cook depends on INTEL_IOMMU && ACPI 27869575d38SShane Wang 2796b0c3d44SSam Ravnborgconfig X86_32_SMP 2806b0c3d44SSam Ravnborg def_bool y 2816b0c3d44SSam Ravnborg depends on X86_32 && SMP 2826b0c3d44SSam Ravnborg 2836b0c3d44SSam Ravnborgconfig X86_64_SMP 2846b0c3d44SSam Ravnborg def_bool y 2856b0c3d44SSam Ravnborg depends on X86_64 && SMP 2866b0c3d44SSam Ravnborg 287ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 288ccbeed3aSTejun Heo def_bool y 28960a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 290ccbeed3aSTejun Heo 291d61931d8SBorislav Petkovconfig ARCH_HWEIGHT_CFLAGS 292d61931d8SBorislav Petkov string 293d61931d8SBorislav Petkov default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 294d61931d8SBorislav Petkov default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 295d61931d8SBorislav Petkov 2962b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 2972b144498SSrikar Dronamraju def_bool y 2982b144498SSrikar Dronamraju 299d20642f0SRob Herringconfig FIX_EARLYCON_MEM 300d20642f0SRob Herring def_bool y 301d20642f0SRob Herring 3029ccaf77cSKees Cookconfig DEBUG_RODATA 3039ccaf77cSKees Cook def_bool y 3049ccaf77cSKees Cook 30598233368SKirill A. Shutemovconfig PGTABLE_LEVELS 30698233368SKirill A. Shutemov int 30798233368SKirill A. Shutemov default 4 if X86_64 30898233368SKirill A. Shutemov default 3 if X86_PAE 30998233368SKirill A. Shutemov default 2 31098233368SKirill A. Shutemov 311506f1d07SSam Ravnborgsource "init/Kconfig" 312dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3138d5fffb9SSam Ravnborg 314506f1d07SSam Ravnborgmenu "Processor type and features" 315506f1d07SSam Ravnborg 3165ee71535SRandy Dunlapconfig ZONE_DMA 3175ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3185ee71535SRandy Dunlap default y 3195ee71535SRandy Dunlap help 3205ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3215ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3225ee71535SRandy Dunlap Disable if no such devices will be used. 3235ee71535SRandy Dunlap 3245ee71535SRandy Dunlap If unsure, say Y. 3255ee71535SRandy Dunlap 326506f1d07SSam Ravnborgconfig SMP 327506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 328506f1d07SSam Ravnborg ---help--- 329506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3304a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3314a474157SRobert Graffham than one CPU, say Y. 332506f1d07SSam Ravnborg 3334a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 334506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 335506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3364a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 337506f1d07SSam Ravnborg will run faster if you say N here. 338506f1d07SSam Ravnborg 339506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 340506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 341506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 342506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 343506f1d07SSam Ravnborg 344506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 345506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 346506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 347506f1d07SSam Ravnborg 348395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 349506f1d07SSam Ravnborg <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 350506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 351506f1d07SSam Ravnborg 352506f1d07SSam Ravnborg If you don't know what to do here, say N. 353506f1d07SSam Ravnborg 3549def39beSJosh Triplettconfig X86_FEATURE_NAMES 3559def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3569def39beSJosh Triplett default y 3579def39beSJosh Triplett ---help--- 3589def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3599def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3609def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3619def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3629def39beSJosh Triplett 3639def39beSJosh Triplett If in doubt, say Y. 3649def39beSJosh Triplett 3656e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3666e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3676e1315feSBorislav Petkov default y 3686e1315feSBorislav Petkov ---help--- 3696e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 3706e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 3716e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 3726e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 3736e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 3746e1315feSBorislav Petkov slower code. 3756e1315feSBorislav Petkov 37606cd9a7dSYinghai Luconfig X86_X2APIC 37706cd9a7dSYinghai Lu bool "Support x2apic" 37819e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 37906cd9a7dSYinghai Lu ---help--- 38006cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 38106cd9a7dSYinghai Lu 38206cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 38306cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 38406cd9a7dSYinghai Lu 38506cd9a7dSYinghai Lu If you don't know what to do here, say N. 38606cd9a7dSYinghai Lu 3876695c85bSYinghai Luconfig X86_MPPARSE 3886e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 3897a527688SJan Beulich default y 3905ab74722SIngo Molnar depends on X86_LOCAL_APIC 3918f9ca475SIngo Molnar ---help--- 3926695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 3936695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 3946695c85bSYinghai Lu 39526f7ef14SYinghai Luconfig X86_BIGSMP 39626f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 39726f7ef14SYinghai Lu depends on X86_32 && SMP 3988f9ca475SIngo Molnar ---help--- 39926f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 400506f1d07SSam Ravnborg 401ddd70cf9SJun Nakajimaconfig GOLDFISH 402ddd70cf9SJun Nakajima def_bool y 403ddd70cf9SJun Nakajima depends on X86_GOLDFISH 404ddd70cf9SJun Nakajima 4058425091fSRavikiran G Thirumalaiif X86_32 406c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 407c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 408c5c606d9SRavikiran G Thirumalai default y 4098f9ca475SIngo Molnar ---help--- 41006ac8346SIngo Molnar If you disable this option then the kernel will only support 41106ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 41206ac8346SIngo Molnar systems out there.) 41306ac8346SIngo Molnar 4148425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4158425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 416cb7b8023SBen Hutchings Goldfish (Android emulator) 4178425091fSRavikiran G Thirumalai AMD Elan 4188425091fSRavikiran G Thirumalai RDC R-321x SoC 4198425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 42083125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4213f4110a4SThomas Gleixner Moorestown MID devices 42206ac8346SIngo Molnar 42306ac8346SIngo Molnar If you have one of these systems, or if you want to build a 42406ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4258425091fSRavikiran G Thirumalaiendif 42606ac8346SIngo Molnar 4278425091fSRavikiran G Thirumalaiif X86_64 4288425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4298425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4308425091fSRavikiran G Thirumalai default y 4318425091fSRavikiran G Thirumalai ---help--- 4328425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4338425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4348425091fSRavikiran G Thirumalai systems out there.) 4358425091fSRavikiran G Thirumalai 4368425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4378425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 43844b111b5SSteffen Persvold Numascale NumaChip 4398425091fSRavikiran G Thirumalai ScaleMP vSMP 4408425091fSRavikiran G Thirumalai SGI Ultraviolet 4418425091fSRavikiran G Thirumalai 4428425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4438425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4448425091fSRavikiran G Thirumalaiendif 445c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 446c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 44744b111b5SSteffen Persvoldconfig X86_NUMACHIP 44844b111b5SSteffen Persvold bool "Numascale NumaChip" 44944b111b5SSteffen Persvold depends on X86_64 45044b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 45144b111b5SSteffen Persvold depends on NUMA 45244b111b5SSteffen Persvold depends on SMP 45344b111b5SSteffen Persvold depends on X86_X2APIC 454f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 45544b111b5SSteffen Persvold ---help--- 45644b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 45744b111b5SSteffen Persvold enable more than ~168 cores. 45844b111b5SSteffen Persvold If you don't have one of these, you should say N here. 45903b48632SNick Piggin 4606a48565eSIngo Molnarconfig X86_VSMP 461c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 4626276a074SBorislav Petkov select HYPERVISOR_GUEST 4636a48565eSIngo Molnar select PARAVIRT 4646a48565eSIngo Molnar depends on X86_64 && PCI 465c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 466ead91d4bSShai Fultheim depends on SMP 4678f9ca475SIngo Molnar ---help--- 4686a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 4696a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 4706a48565eSIngo Molnar if you have one of these machines. 4716a48565eSIngo Molnar 472c5c606d9SRavikiran G Thirumalaiconfig X86_UV 473c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 474c5c606d9SRavikiran G Thirumalai depends on X86_64 475c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 47654c28d29SJack Steiner depends on NUMA 4771ecb4ae5SAndrew Morton depends on EFI 4789d6c26e7SSuresh Siddha depends on X86_X2APIC 4791222e564SIngo Molnar depends on PCI 480c5c606d9SRavikiran G Thirumalai ---help--- 481c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 482c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 483c5c606d9SRavikiran G Thirumalai 484c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 485c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 486506f1d07SSam Ravnborg 487ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 488ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 489cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 490ddd70cf9SJun Nakajima ---help--- 491ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 492ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 493ddd70cf9SJun Nakajima Goldfish emulator say N here. 494ddd70cf9SJun Nakajima 495c751e17bSThomas Gleixnerconfig X86_INTEL_CE 496c751e17bSThomas Gleixner bool "CE4100 TV platform" 497c751e17bSThomas Gleixner depends on PCI 498c751e17bSThomas Gleixner depends on PCI_GODIRECT 4996084a6e2SJiang Liu depends on X86_IO_APIC 500c751e17bSThomas Gleixner depends on X86_32 501c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 50237bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 503da6b737bSSebastian Andrzej Siewior select OF 504da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 505c751e17bSThomas Gleixner ---help--- 506c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 507c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 508c751e17bSThomas Gleixner boxes and media devices. 509c751e17bSThomas Gleixner 5104cb9b00fSDavid Cohenconfig X86_INTEL_MID 51143605ef1SAlan Cox bool "Intel MID platform support" 51243605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 513edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5141ea7c673SAlan Cox depends on PCI 5153fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5161ea7c673SAlan Cox depends on X86_IO_APIC 5177c9c3a1eSAlan Cox select SFI 5184cb9b00fSDavid Cohen select I2C 5197c9c3a1eSAlan Cox select DW_APB_TIMER 5201ea7c673SAlan Cox select APB_TIMER 5211ea7c673SAlan Cox select INTEL_SCU_IPC 52215a713dfSMika Westerberg select MFD_INTEL_MSIC 5231ea7c673SAlan Cox ---help--- 5244cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5254cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5264cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5271ea7c673SAlan Cox 5284cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5294cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 53043605ef1SAlan Cox 5318bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5328bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5338bbc2a13SBryan O'Donoghue depends on X86_32 5348bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5358bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5368bbc2a13SBryan O'Donoghue depends on X86_TSC 5378bbc2a13SBryan O'Donoghue depends on PCI 5388bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5398bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5408bbc2a13SBryan O'Donoghue select IOSF_MBI 5418bbc2a13SBryan O'Donoghue select INTEL_IMR 5429ab6eb51SAndy Shevchenko select COMMON_CLK 5438bbc2a13SBryan O'Donoghue ---help--- 5448bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5458bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5468bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5478bbc2a13SBryan O'Donoghue 5483d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5493d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 550eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5513d48aab1SMika Westerberg select COMMON_CLK 5520f531431SMathias Nyman select PINCTRL 553eebb3e8dSAndy Shevchenko select IOSF_MBI 5543d48aab1SMika Westerberg ---help--- 5553d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 5563d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 5570f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 5580f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 5593d48aab1SMika Westerberg 56092082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 56192082a88SKen Xue bool "AMD ACPI2Platform devices support" 56292082a88SKen Xue depends on ACPI 56392082a88SKen Xue select COMMON_CLK 56492082a88SKen Xue select PINCTRL 56592082a88SKen Xue ---help--- 56692082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 56792082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 56892082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 56992082a88SKen Xue implemented under PINCTRL subsystem. 57092082a88SKen Xue 571ced3ce76SDavid E. Boxconfig IOSF_MBI 572ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 573ced3ce76SDavid E. Box depends on PCI 574ced3ce76SDavid E. Box ---help--- 575ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 576ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 577ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 578ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 579ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 580ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 581ced3ce76SDavid E. Box This list is not meant to be exclusive. 582ced3ce76SDavid E. Box - BayTrail 583ced3ce76SDavid E. Box - Braswell 584ced3ce76SDavid E. Box - Quark 585ced3ce76SDavid E. Box 586ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 587ced3ce76SDavid E. Box 588ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 589ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 590ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 591ed2226bdSDavid E. Box ---help--- 592ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 593ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 594ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 595ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 596ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 597ed2226bdSDavid E. Box device they want to access. 598ed2226bdSDavid E. Box 599ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 600ed2226bdSDavid E. Box 601c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 602c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 603506f1d07SSam Ravnborg depends on X86_32 604c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 605c5c606d9SRavikiran G Thirumalai select M486 606c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 607c5c606d9SRavikiran G Thirumalai ---help--- 608c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 609c5c606d9SRavikiran G Thirumalai as R-8610-(G). 610c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 611c5c606d9SRavikiran G Thirumalai 612e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6139c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6149c398017SIngo Molnar depends on X86_32 && SMP 615c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6168f9ca475SIngo Molnar ---help--- 617b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 618b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 619b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 620b5660ba7SH. Peter Anvin one and will fallback to default. 621d49c4288SYinghai Lu 622c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 623d49c4288SYinghai Lu 624d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6256fc108a0SJan Beulich def_bool y 626d949f36fSLinus Torvalds # MCE code calls memory_failure(): 627d949f36fSLinus Torvalds depends on X86_MCE 628d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 629d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 630d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 631d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 632d949f36fSLinus Torvalds 63383125a3aSAlessandro Rubiniconfig STA2X11 63483125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 63583125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 63683125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 63783125a3aSAlessandro Rubini select X86_DMA_REMAP 63883125a3aSAlessandro Rubini select SWIOTLB 63983125a3aSAlessandro Rubini select MFD_STA2X11 64083125a3aSAlessandro Rubini select ARCH_REQUIRE_GPIOLIB 64183125a3aSAlessandro Rubini default n 64283125a3aSAlessandro Rubini ---help--- 64383125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 64483125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 64583125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 64683125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 64783125a3aSAlessandro Rubini standard PC machines. 64883125a3aSAlessandro Rubini 64982148d1dSShérabconfig X86_32_IRIS 65082148d1dSShérab tristate "Eurobraille/Iris poweroff module" 65182148d1dSShérab depends on X86_32 65282148d1dSShérab ---help--- 65382148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 65482148d1dSShérab to shut themselves down properly. A special I/O sequence is 65582148d1dSShérab needed to do so, which is what this module does at 65682148d1dSShérab kernel shutdown. 65782148d1dSShérab 65882148d1dSShérab This is only for Iris machines from EuroBraille. 65982148d1dSShérab 66082148d1dSShérab If unused, say N. 66182148d1dSShérab 662ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 6633c2362e6SHarvey Harrison def_bool y 6643c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 665a87d0914SKen Chen depends on X86 6668f9ca475SIngo Molnar ---help--- 667506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 668506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 669506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 670506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 671506f1d07SSam Ravnborg 672506f1d07SSam Ravnborg If in doubt, say "Y". 673506f1d07SSam Ravnborg 6746276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 6756276a074SBorislav Petkov bool "Linux guest support" 6768f9ca475SIngo Molnar ---help--- 6776276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 6786276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 6796276a074SBorislav Petkov setup. 680506f1d07SSam Ravnborg 6816276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 6826276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 683506f1d07SSam Ravnborg 6846276a074SBorislav Petkovif HYPERVISOR_GUEST 685506f1d07SSam Ravnborg 686e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 687e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 6888f9ca475SIngo Molnar ---help--- 689e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 690e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 691e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 692e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 693e61bd94aSEduardo Pereira Habkost 6946276a074SBorislav Petkovconfig PARAVIRT_DEBUG 6956276a074SBorislav Petkov bool "paravirt-ops debugging" 6966276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 6976276a074SBorislav Petkov ---help--- 6986276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 6996276a074SBorislav Petkov a paravirt_op is missing when it is called. 7006276a074SBorislav Petkov 701b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 702b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7036ea30386SKees Cook depends on PARAVIRT && SMP 70462c7a1e9SIngo Molnar select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS 705b4ecc126SJeremy Fitzhardinge ---help--- 706b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 707b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 708b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 709b4ecc126SJeremy Fitzhardinge 7104c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7114c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 712b4ecc126SJeremy Fitzhardinge 7134c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 714b4ecc126SJeremy Fitzhardinge 71545e898b7SWaiman Longconfig QUEUED_LOCK_STAT 71645e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 71745e898b7SWaiman Long depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS 71845e898b7SWaiman Long ---help--- 71945e898b7SWaiman Long Enable the collection of statistical data on the slowpath 72045e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 72145e898b7SWaiman Long them on debugfs. 72245e898b7SWaiman Long 7236276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7246276a074SBorislav Petkov 7256276a074SBorislav Petkovconfig KVM_GUEST 7266276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7276276a074SBorislav Petkov depends on PARAVIRT 7286276a074SBorislav Petkov select PARAVIRT_CLOCK 7296276a074SBorislav Petkov default y 7306276a074SBorislav Petkov ---help--- 7316276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7326276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7336276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7346276a074SBorislav Petkov underlying device model, the host provides the guest with 7356276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7366276a074SBorislav Petkov 7371e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7381e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7391e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7401e20eb85SSrivatsa Vaddagiri default n 7411e20eb85SSrivatsa Vaddagiri ---help--- 7421e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7431e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7441e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7451e20eb85SSrivatsa Vaddagiri 7466276a074SBorislav Petkovsource "arch/x86/lguest/Kconfig" 7476276a074SBorislav Petkov 7486276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7496276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7506276a074SBorislav Petkov depends on PARAVIRT 7516276a074SBorislav Petkov default n 7526276a074SBorislav Petkov ---help--- 7536276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7546276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7556276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 7566276a074SBorislav Petkov that, there can be a small performance impact. 7576276a074SBorislav Petkov 7586276a074SBorislav Petkov If in doubt, say N here. 7596276a074SBorislav Petkov 7607af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 7617af192c9SGerd Hoffmann bool 7627af192c9SGerd Hoffmann 7636276a074SBorislav Petkovendif #HYPERVISOR_GUEST 76497349135SJeremy Fitzhardinge 76508677214SYinghai Luconfig NO_BOOTMEM 766774ea0bcSYinghai Lu def_bool y 76708677214SYinghai Lu 768506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 769506f1d07SSam Ravnborg 770506f1d07SSam Ravnborgconfig HPET_TIMER 7713c2362e6SHarvey Harrison def_bool X86_64 772506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 7738f9ca475SIngo Molnar ---help--- 774506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 775506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 776506f1d07SSam Ravnborg present. 777506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 778506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 779506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 7804e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 7814e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 782506f1d07SSam Ravnborg 783506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 784506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 785506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 786506f1d07SSam Ravnborg 787506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 788506f1d07SSam Ravnborg 789506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 7903c2362e6SHarvey Harrison def_bool y 7919d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 792506f1d07SSam Ravnborg 793bb24c471SJacob Panconfig APB_TIMER 794933b9463SAlan Cox def_bool y if X86_INTEL_MID 795933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 79606c3df49SJamie Iles select DW_APB_TIMER 797a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 798bb24c471SJacob Pan help 799bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 800bb24c471SJacob Pan The APBT provides a stable time base on SMP 801bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 802bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 803bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 804bb24c471SJacob Pan 8056a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 806506f1d07SSam Ravnborg# The code disables itself when not needed. 8077ae9392cSThomas Petazzoniconfig DMI 8087ae9392cSThomas Petazzoni default y 809cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8106a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8118f9ca475SIngo Molnar ---help--- 8127ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8137ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8147ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8157ae9392cSThomas Petazzoni BIOS code. 8167ae9392cSThomas Petazzoni 817506f1d07SSam Ravnborgconfig GART_IOMMU 81838901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 819506f1d07SSam Ravnborg select SWIOTLB 82023ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8218f9ca475SIngo Molnar ---help--- 822ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 823ced3c42cSIngo Molnar GART based hardware IOMMUs. 824ced3c42cSIngo Molnar 825ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 826ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 827ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 828ced3c42cSIngo Molnar 829ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 830ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 831ced3c42cSIngo Molnar 832ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 833ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 834ced3c42cSIngo Molnar 32-bit limited device. 835ced3c42cSIngo Molnar 836ced3c42cSIngo Molnar If unsure, say Y. 837506f1d07SSam Ravnborg 838506f1d07SSam Ravnborgconfig CALGARY_IOMMU 839506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 840506f1d07SSam Ravnborg select SWIOTLB 8416ea30386SKees Cook depends on X86_64 && PCI 8428f9ca475SIngo Molnar ---help--- 843506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 844506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 845506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 846506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 847506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 848506f1d07SSam Ravnborg prevents them from going anywhere except their intended 849506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 850506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 851506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 852506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 853506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 854506f1d07SSam Ravnborg If unsure, say Y. 855506f1d07SSam Ravnborg 856506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 8573c2362e6SHarvey Harrison def_bool y 8583c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 859506f1d07SSam Ravnborg depends on CALGARY_IOMMU 8608f9ca475SIngo Molnar ---help--- 861506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 862506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 863506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 864506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 865506f1d07SSam Ravnborg If unsure, say Y. 866506f1d07SSam Ravnborg 867506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 868506f1d07SSam Ravnborgconfig SWIOTLB 869a1afd01cSJoerg Roedel def_bool y if X86_64 8708f9ca475SIngo Molnar ---help--- 871506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 8724454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 8734454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 8744454d327SJoe Millenbach with more than 3 GB of memory. 8754454d327SJoe Millenbach If unsure, say Y. 876506f1d07SSam Ravnborg 877a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 8783120e25eSJan Beulich def_bool y 8793120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 880d25e26b6SLinus Torvalds 8811184dc2fSMike Travisconfig MAXSMP 882ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 8836ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 88436f5101aSMike Travis select CPUMASK_OFFSTACK 8858f9ca475SIngo Molnar ---help--- 886ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 8871184dc2fSMike Travis If unsure, say N. 888506f1d07SSam Ravnborg 889506f1d07SSam Ravnborgconfig NR_CPUS 89036f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 8912a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 892bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 893b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 89478637a97SMike Travis default "1" if !SMP 895b53b5edaSJosh Boyer default "8192" if MAXSMP 896b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 897c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 898c5c19941SKirill A. Shutemov default "64" if SMP 8998f9ca475SIngo Molnar ---help--- 900506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 901bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 902cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 903506f1d07SSam Ravnborg minimum value which makes sense is 2. 904506f1d07SSam Ravnborg 905506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 906506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 907506f1d07SSam Ravnborg 908506f1d07SSam Ravnborgconfig SCHED_SMT 909506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 910c8e56d20SBorislav Petkov depends on SMP 9118f9ca475SIngo Molnar ---help--- 912506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 913506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 914506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 915506f1d07SSam Ravnborg N here. 916506f1d07SSam Ravnborg 917506f1d07SSam Ravnborgconfig SCHED_MC 9183c2362e6SHarvey Harrison def_bool y 9193c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 920c8e56d20SBorislav Petkov depends on SMP 9218f9ca475SIngo Molnar ---help--- 922506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 923506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 924506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 925506f1d07SSam Ravnborg 926506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 927506f1d07SSam Ravnborg 92830b8b006SThomas Gleixnerconfig UP_LATE_INIT 92930b8b006SThomas Gleixner def_bool y 930ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 93130b8b006SThomas Gleixner 932506f1d07SSam Ravnborgconfig X86_UP_APIC 93350849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 93450849eefSJan Beulich default PCI_MSI 93538a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 9368f9ca475SIngo Molnar ---help--- 937506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 938506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 939506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 940506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 941506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 942506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 943506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 944506f1d07SSam Ravnborg lockups. 945506f1d07SSam Ravnborg 946506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 947506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 948506f1d07SSam Ravnborg depends on X86_UP_APIC 9498f9ca475SIngo Molnar ---help--- 950506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 951506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 952506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 953506f1d07SSam Ravnborg 954506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 955506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 956506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 957506f1d07SSam Ravnborg 958506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 9593c2362e6SHarvey Harrison def_bool y 9600dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 961b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 96252f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 963506f1d07SSam Ravnborg 964506f1d07SSam Ravnborgconfig X86_IO_APIC 965b1da1e71SJan Beulich def_bool y 966b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 967506f1d07SSam Ravnborg 96841b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 96941b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 97041b9eb26SStefan Assmann depends on X86_IO_APIC 9718f9ca475SIngo Molnar ---help--- 97241b9eb26SStefan Assmann This option enables a workaround that fixes a source of 97341b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 97441b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 97541b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 97641b9eb26SStefan Assmann 97741b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 97841b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 97941b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 98041b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 98141b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 98241b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 98341b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 98441b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 98541b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 98641b9eb26SStefan Assmann down (vital) interrupt lines. 98741b9eb26SStefan Assmann 98841b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 98941b9eb26SStefan Assmann increased on these systems. 99041b9eb26SStefan Assmann 991506f1d07SSam Ravnborgconfig X86_MCE 992bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 993648ed940SChen, Gong select GENERIC_ALLOCATOR 994e57dbaf7SBorislav Petkov default y 995506f1d07SSam Ravnborg ---help--- 996bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 997bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 998506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 999bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10004efc0670SAndi Kleen 1001506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10023c2362e6SHarvey Harrison def_bool y 10033c2362e6SHarvey Harrison prompt "Intel MCE features" 1004c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10058f9ca475SIngo Molnar ---help--- 1006506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1007506f1d07SSam Ravnborg the thermal monitor. 1008506f1d07SSam Ravnborg 1009506f1d07SSam Ravnborgconfig X86_MCE_AMD 10103c2362e6SHarvey Harrison def_bool y 10113c2362e6SHarvey Harrison prompt "AMD MCE features" 1012c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10138f9ca475SIngo Molnar ---help--- 1014506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1015506f1d07SSam Ravnborg the DRAM Error Threshold. 1016506f1d07SSam Ravnborg 10174efc0670SAndi Kleenconfig X86_ANCIENT_MCE 10186fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1019c31d9633SAndi Kleen depends on X86_32 && X86_MCE 10204efc0670SAndi Kleen ---help--- 10214efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 10225065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 10234efc0670SAndi Kleen line. 10244efc0670SAndi Kleen 1025b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1026b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 10276fc108a0SJan Beulich def_bool y 1028b2762686SAndi Kleen 1029ea149b36SAndi Kleenconfig X86_MCE_INJECT 1030c1ebf835SAndi Kleen depends on X86_MCE 1031ea149b36SAndi Kleen tristate "Machine check injector support" 1032ea149b36SAndi Kleen ---help--- 1033ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1034ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1035ea149b36SAndi Kleen QA it is safe to say n. 1036ea149b36SAndi Kleen 10374efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 10384efc0670SAndi Kleen def_bool y 10395bb38adcSAndi Kleen depends on X86_MCE_INTEL 10404efc0670SAndi Kleen 1041*e633c65aSKan Liangsource "arch/x86/Kconfig.perf" 1042*e633c65aSKan Liang 10435aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 10441e642812SIngo Molnar bool "Legacy VM86 support" 10455aef51c3SAndy Lutomirski default n 1046506f1d07SSam Ravnborg depends on X86_32 10478f9ca475SIngo Molnar ---help--- 10485aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 10495aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 10505aef51c3SAndy Lutomirski 10515aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 10525aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 10535aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 10545aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 10555aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 10561e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 10571e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 10581e642812SIngo Molnar mode might be faster than emulation and you might want to 10591e642812SIngo Molnar enable this option. 10605aef51c3SAndy Lutomirski 10611e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 10621e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 10631e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 10641e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 10655aef51c3SAndy Lutomirski 10661e642812SIngo Molnar Enabling this option increases the complexity of the kernel 10671e642812SIngo Molnar and slows down exception handling a tiny bit. 10685aef51c3SAndy Lutomirski 10691e642812SIngo Molnar If unsure, say N here. 10705aef51c3SAndy Lutomirski 10715aef51c3SAndy Lutomirskiconfig VM86 10725aef51c3SAndy Lutomirski bool 10735aef51c3SAndy Lutomirski default X86_LEGACY_VM86 107434273f41SH. Peter Anvin 107534273f41SH. Peter Anvinconfig X86_16BIT 107634273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 107734273f41SH. Peter Anvin default y 1078a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 107934273f41SH. Peter Anvin ---help--- 108034273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 108134273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 108234273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 108334273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 108434273f41SH. Peter Anvin 108534273f41SH. Peter Anvinconfig X86_ESPFIX32 108634273f41SH. Peter Anvin def_bool y 108734273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1088506f1d07SSam Ravnborg 1089197725deSH. Peter Anvinconfig X86_ESPFIX64 1090197725deSH. Peter Anvin def_bool y 109134273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1092506f1d07SSam Ravnborg 10931ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 10941ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 10951ad83c85SAndy Lutomirski default y 10961ad83c85SAndy Lutomirski depends on X86_64 10971ad83c85SAndy Lutomirski ---help--- 10981ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 10991ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 11001ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11011ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11021ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11031ad83c85SAndy Lutomirski 0xffffffffff600?00. 11041ad83c85SAndy Lutomirski 11051ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 11061ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 11071ad83c85SAndy Lutomirski 11081ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 11091ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 11101ad83c85SAndy Lutomirski 1111506f1d07SSam Ravnborgconfig TOSHIBA 1112506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1113506f1d07SSam Ravnborg depends on X86_32 1114506f1d07SSam Ravnborg ---help--- 1115506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1116506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1117506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1118506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1119506f1d07SSam Ravnborg 1120506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1121506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1122506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1123506f1d07SSam Ravnborg 1124506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1125506f1d07SSam Ravnborg Say N otherwise. 1126506f1d07SSam Ravnborg 1127506f1d07SSam Ravnborgconfig I8K 1128039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1129949a9d70SJean Delvare select HWMON 1130039ae585SPali Rohár select SENSORS_DELL_SMM 1131506f1d07SSam Ravnborg ---help--- 1132039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1133039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1134039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1135039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1136039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1137039ae585SPali Rohár needed userspace package i8kutils. 1138506f1d07SSam Ravnborg 1139039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1140039ae585SPali Rohár use userspace package i8kutils. 1141506f1d07SSam Ravnborg Say N otherwise. 1142506f1d07SSam Ravnborg 1143506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 11449ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 11459ba16087SJan Beulich depends on X86_32 1146506f1d07SSam Ravnborg ---help--- 1147506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1148506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1149506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1150506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1151506f1d07SSam Ravnborg system. 1152506f1d07SSam Ravnborg 1153506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 11545e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1155506f1d07SSam Ravnborg 1156506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1157506f1d07SSam Ravnborg enable this option even if you don't need it. 1158506f1d07SSam Ravnborg Say N otherwise. 1159506f1d07SSam Ravnborg 1160506f1d07SSam Ravnborgconfig MICROCODE 11619a2bc335SBorislav Petkov bool "CPU microcode loading support" 11629a2bc335SBorislav Petkov default y 116380030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1164506f1d07SSam Ravnborg select FW_LOADER 1165506f1d07SSam Ravnborg ---help--- 1166506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 11675f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 11685f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 11695f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 11705f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 11715f9c01aaSBorislav Petkov the Linux kernel. 1172506f1d07SSam Ravnborg 11735f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 11745f9c01aaSBorislav Petkov in Documentation/x86/early-microcode.txt. For that you need to enable 11755f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 11765f9c01aaSBorislav Petkov initrd for microcode blobs. 1177506f1d07SSam Ravnborg 11785f9c01aaSBorislav Petkov In addition, you can build-in the microcode into the kernel. For that you 11795f9c01aaSBorislav Petkov need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 11805f9c01aaSBorislav Petkov to the CONFIG_EXTRA_FIRMWARE config option. 1181506f1d07SSam Ravnborg 11828d86f390SPeter Orubaconfig MICROCODE_INTEL 1183e43f6e67SBorislav Petkov bool "Intel microcode loading support" 11848d86f390SPeter Oruba depends on MICROCODE 11858d86f390SPeter Oruba default MICROCODE 11868d86f390SPeter Oruba select FW_LOADER 11878f9ca475SIngo Molnar ---help--- 11888d86f390SPeter Oruba This options enables microcode patch loading support for Intel 11898d86f390SPeter Oruba processors. 11908d86f390SPeter Oruba 1191b8989db9SAlan For the current Intel microcode data package go to 1192b8989db9SAlan <https://downloadcenter.intel.com> and search for 1193b8989db9SAlan 'Linux Processor Microcode Data File'. 11948d86f390SPeter Oruba 119580cc9f10SPeter Orubaconfig MICROCODE_AMD 1196e43f6e67SBorislav Petkov bool "AMD microcode loading support" 119780cc9f10SPeter Oruba depends on MICROCODE 119880cc9f10SPeter Oruba select FW_LOADER 11998f9ca475SIngo Molnar ---help--- 120080cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 120180cc9f10SPeter Oruba processors will be enabled. 120280cc9f10SPeter Oruba 1203506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12043c2362e6SHarvey Harrison def_bool y 1205506f1d07SSam Ravnborg depends on MICROCODE 1206506f1d07SSam Ravnborg 1207c7ab62bfSHuang Ruiconfig PERF_EVENTS_AMD_POWER 1208c7ab62bfSHuang Rui depends on PERF_EVENTS && CPU_SUP_AMD 1209c7ab62bfSHuang Rui tristate "AMD Processor Power Reporting Mechanism" 1210c7ab62bfSHuang Rui ---help--- 1211c7ab62bfSHuang Rui Provide power reporting mechanism support for AMD processors. 1212c7ab62bfSHuang Rui Currently, it leverages X86_FEATURE_ACC_POWER 1213c7ab62bfSHuang Rui (CPUID Fn8000_0007_EDX[12]) interface to calculate the 1214c7ab62bfSHuang Rui average power consumption on Family 15h processors. 1215c7ab62bfSHuang Rui 1216506f1d07SSam Ravnborgconfig X86_MSR 1217506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 12188f9ca475SIngo Molnar ---help--- 1219506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1220506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1221506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1222506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1223506f1d07SSam Ravnborg systems. 1224506f1d07SSam Ravnborg 1225506f1d07SSam Ravnborgconfig X86_CPUID 1226506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 12278f9ca475SIngo Molnar ---help--- 1228506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1229506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1230506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1231506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1232506f1d07SSam Ravnborg 1233506f1d07SSam Ravnborgchoice 1234506f1d07SSam Ravnborg prompt "High Memory Support" 12356fc108a0SJan Beulich default HIGHMEM4G 1236506f1d07SSam Ravnborg depends on X86_32 1237506f1d07SSam Ravnborg 1238506f1d07SSam Ravnborgconfig NOHIGHMEM 1239506f1d07SSam Ravnborg bool "off" 1240506f1d07SSam Ravnborg ---help--- 1241506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1242506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1243506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1244506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1245506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1246506f1d07SSam Ravnborg "high memory". 1247506f1d07SSam Ravnborg 1248506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1249506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1250506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1251506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1252506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1253506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1254506f1d07SSam Ravnborg possible. 1255506f1d07SSam Ravnborg 1256506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1257506f1d07SSam Ravnborg answer "4GB" here. 1258506f1d07SSam Ravnborg 1259506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1260506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1261506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1262506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1263506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1264506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1265506f1d07SSam Ravnborg 1266506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1267506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1268506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1269506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1270506f1d07SSam Ravnborg kernel at boot time.) 1271506f1d07SSam Ravnborg 1272506f1d07SSam Ravnborg If unsure, say "off". 1273506f1d07SSam Ravnborg 1274506f1d07SSam Ravnborgconfig HIGHMEM4G 1275506f1d07SSam Ravnborg bool "4GB" 12768f9ca475SIngo Molnar ---help--- 1277506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1278506f1d07SSam Ravnborg gigabytes of physical RAM. 1279506f1d07SSam Ravnborg 1280506f1d07SSam Ravnborgconfig HIGHMEM64G 1281506f1d07SSam Ravnborg bool "64GB" 1282eb068e78SH. Peter Anvin depends on !M486 1283506f1d07SSam Ravnborg select X86_PAE 12848f9ca475SIngo Molnar ---help--- 1285506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1286506f1d07SSam Ravnborg gigabytes of physical RAM. 1287506f1d07SSam Ravnborg 1288506f1d07SSam Ravnborgendchoice 1289506f1d07SSam Ravnborg 1290506f1d07SSam Ravnborgchoice 12916a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1292506f1d07SSam Ravnborg default VMSPLIT_3G 1293506f1d07SSam Ravnborg depends on X86_32 12948f9ca475SIngo Molnar ---help--- 1295506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1296506f1d07SSam Ravnborg 1297506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1298506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1299506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1300506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1301506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1302506f1d07SSam Ravnborg available to user programs, making the address space there 1303506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1304506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1305506f1d07SSam Ravnborg kernel modules. 1306506f1d07SSam Ravnborg 1307506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1308506f1d07SSam Ravnborg option alone! 1309506f1d07SSam Ravnborg 1310506f1d07SSam Ravnborg config VMSPLIT_3G 1311506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1312506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1313506f1d07SSam Ravnborg depends on !X86_PAE 1314506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1315506f1d07SSam Ravnborg config VMSPLIT_2G 1316506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1317506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1318506f1d07SSam Ravnborg depends on !X86_PAE 1319506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1320506f1d07SSam Ravnborg config VMSPLIT_1G 1321506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1322506f1d07SSam Ravnborgendchoice 1323506f1d07SSam Ravnborg 1324506f1d07SSam Ravnborgconfig PAGE_OFFSET 1325506f1d07SSam Ravnborg hex 1326506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1327506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1328506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1329506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1330506f1d07SSam Ravnborg default 0xC0000000 1331506f1d07SSam Ravnborg depends on X86_32 1332506f1d07SSam Ravnborg 1333506f1d07SSam Ravnborgconfig HIGHMEM 13343c2362e6SHarvey Harrison def_bool y 1335506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1336506f1d07SSam Ravnborg 1337506f1d07SSam Ravnborgconfig X86_PAE 13389ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1339506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 13409d99c712SChristian Melki select SWIOTLB 13418f9ca475SIngo Molnar ---help--- 1342506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1343506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1344506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1345506f1d07SSam Ravnborg consumes more pagetable space per process. 1346506f1d07SSam Ravnborg 1347600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 13483120e25eSJan Beulich def_bool y 13493120e25eSJan Beulich depends on X86_64 || X86_PAE 1350600715dcSJeremy Fitzhardinge 135166f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 13523120e25eSJan Beulich def_bool y 13533120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 135466f2b061SFUJITA Tomonori 135510971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1356e5008abeSLuis R. Rodriguez def_bool y 1357e5008abeSLuis R. Rodriguez depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 13588f9ca475SIngo Molnar ---help--- 135910971ab2SIngo Molnar Certain kernel features effectively disable kernel 136010971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 136110971ab2SIngo Molnar supports them), so don't confuse the user by printing 136210971ab2SIngo Molnar that we have them enabled. 13639e899816SNick Piggin 1364506f1d07SSam Ravnborg# Common NUMA Features 1365506f1d07SSam Ravnborgconfig NUMA 1366fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1367506f1d07SSam Ravnborg depends on SMP 1368b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1369b5660ba7SH. Peter Anvin default y if X86_BIGSMP 13708f9ca475SIngo Molnar ---help--- 1371506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1372fd51b2d7SKOSAKI Motohiro 1373506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1374506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1375506f1d07SSam Ravnborg NUMA awareness to the kernel. 1376506f1d07SSam Ravnborg 1377c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1378fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1379fd51b2d7SKOSAKI Motohiro 1380b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 13817cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1382fd51b2d7SKOSAKI Motohiro 1383fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1384506f1d07SSam Ravnborg 1385eec1d4faSHans Rosenfeldconfig AMD_NUMA 13863c2362e6SHarvey Harrison def_bool y 13873c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 13885da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 13898f9ca475SIngo Molnar ---help--- 1390eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1391eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1392eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1393eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1394eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1395506f1d07SSam Ravnborg 1396506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 13973c2362e6SHarvey Harrison def_bool y 13983c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1399506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1400506f1d07SSam Ravnborg select ACPI_NUMA 14018f9ca475SIngo Molnar ---help--- 1402506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1403506f1d07SSam Ravnborg 14046ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 14056ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 14066ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 14076ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 14086ec6e0d9SSuresh Siddha# for details. 14096ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 14106ec6e0d9SSuresh Siddha def_bool y 14116ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 14126ec6e0d9SSuresh Siddha 1413506f1d07SSam Ravnborgconfig NUMA_EMU 1414506f1d07SSam Ravnborg bool "NUMA emulation" 14151b7e03efSTejun Heo depends on NUMA 14168f9ca475SIngo Molnar ---help--- 1417506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1418506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1419506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1420506f1d07SSam Ravnborg 1421506f1d07SSam Ravnborgconfig NODES_SHIFT 1422d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 142351591e31SDavid Rientjes range 1 10 142451591e31SDavid Rientjes default "10" if MAXSMP 1425506f1d07SSam Ravnborg default "6" if X86_64 1426506f1d07SSam Ravnborg default "3" 1427506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 14288f9ca475SIngo Molnar ---help--- 14291184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1430692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1431506f1d07SSam Ravnborg 1432506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 14333c2362e6SHarvey Harrison def_bool y 1434506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1435506f1d07SSam Ravnborg 1436506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 14373c2362e6SHarvey Harrison def_bool y 1438506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1439506f1d07SSam Ravnborg 1440506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1441506f1d07SSam Ravnborg def_bool y 14423b16651fSTejun Heo depends on X86_32 && !NUMA 1443506f1d07SSam Ravnborg 1444506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1445506f1d07SSam Ravnborg def_bool y 1446b263295dSChristoph Lameter depends on NUMA && X86_32 1447506f1d07SSam Ravnborg 1448506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1449506f1d07SSam Ravnborg def_bool y 1450b263295dSChristoph Lameter depends on NUMA && X86_32 1451b263295dSChristoph Lameter 1452506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1453506f1d07SSam Ravnborg def_bool y 14546ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1455506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1456506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1457506f1d07SSam Ravnborg 14583b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 14593b16651fSTejun Heo def_bool y 14603b16651fSTejun Heo depends on X86_64 14613b16651fSTejun Heo 1462506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1463506f1d07SSam Ravnborg def_bool y 1464b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1465506f1d07SSam Ravnborg 1466506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1467a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 14683120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1469a0842b70SToshi Kani help 1470a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1471a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1472a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1473506f1d07SSam Ravnborg 14743b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 14753b16651fSTejun Heo def_bool y 14763b16651fSTejun Heo depends on X86_64 && PROC_KCORE 14773b16651fSTejun Heo 1478a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1479a29815a3SAvi Kivity hex 1480a29815a3SAvi Kivity default 0 if X86_32 1481a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1482a29815a3SAvi Kivity 1483506f1d07SSam Ravnborgsource "mm/Kconfig" 1484506f1d07SSam Ravnborg 14857a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 14867a67832cSDan Williams bool 14877a67832cSDan Williams 1488ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 14897a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 14909f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 14919f53f9faSDan Williams depends on BLK_DEV 14927a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 14939f53f9faSDan Williams select LIBNVDIMM 1494ec776ef6SChristoph Hellwig help 1495ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1496ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1497ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1498ec776ef6SChristoph Hellwig they can be used for persistent storage. 1499ec776ef6SChristoph Hellwig 1500ec776ef6SChristoph Hellwig Say Y if unsure. 1501ec776ef6SChristoph Hellwig 1502506f1d07SSam Ravnborgconfig HIGHPTE 1503506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 15046fc108a0SJan Beulich depends on HIGHMEM 15058f9ca475SIngo Molnar ---help--- 1506506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1507506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1508506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1509506f1d07SSam Ravnborg entries in high memory. 1510506f1d07SSam Ravnborg 15119f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 15129f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 15138f9ca475SIngo Molnar ---help--- 15149f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 15159f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 15169f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 15179f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 15189f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 15199f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 15209f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 15219f077871SJeremy Fitzhardinge Documentation/kernel-parameters.txt to adjust this. 15229f077871SJeremy Fitzhardinge 15239f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 15249f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 15259f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 15269f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 15279f077871SJeremy Fitzhardinge 15289f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 15299f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 15309f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 15319f077871SJeremy Fitzhardinge memory. 15329f077871SJeremy Fitzhardinge 1533c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1534c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1535c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1536c885df50SJeremy Fitzhardinge default y 15378f9ca475SIngo Molnar ---help--- 1538c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1539c885df50SJeremy Fitzhardinge on or off. 1540c885df50SJeremy Fitzhardinge 15419ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1542d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1543d0cd7425SH. Peter Anvin default 64 1544d0cd7425SH. Peter Anvin range 4 640 15458f9ca475SIngo Molnar ---help--- 1546d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1547fc381519SIngo Molnar 1548d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1549d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1550fc381519SIngo Molnar 1551d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1552d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1553d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1554d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1555fc381519SIngo Molnar 1556d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1557d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1558d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1559d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1560d0cd7425SH. Peter Anvin entire low memory range. 1561d0cd7425SH. Peter Anvin 1562d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1563d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1564d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1565d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1566d0cd7425SH. Peter Anvin typical corruption patterns. 1567d0cd7425SH. Peter Anvin 1568d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1569fc381519SIngo Molnar 1570506f1d07SSam Ravnborgconfig MATH_EMULATION 1571506f1d07SSam Ravnborg bool 1572a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1573506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1574506f1d07SSam Ravnborg ---help--- 1575506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1576506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1577506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1578506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1579506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1580506f1d07SSam Ravnborg coprocessor or this emulation. 1581506f1d07SSam Ravnborg 1582506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1583506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1584506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1585506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1586506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1587506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1588506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1589506f1d07SSam Ravnborg intend to use this kernel on different machines. 1590506f1d07SSam Ravnborg 1591506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1592506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1593506f1d07SSam Ravnborg 1594506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1595506f1d07SSam Ravnborg kernel, it won't hurt. 1596506f1d07SSam Ravnborg 1597506f1d07SSam Ravnborgconfig MTRR 15986fc108a0SJan Beulich def_bool y 15996a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1600506f1d07SSam Ravnborg ---help--- 1601506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1602506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1603506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1604506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1605506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1606506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1607506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1608506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1609506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1610506f1d07SSam Ravnborg 1611506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1612506f1d07SSam Ravnborg control registers on other processors can be easily supported 1613506f1d07SSam Ravnborg as well: 1614506f1d07SSam Ravnborg 1615506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1616506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1617506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1618506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1619506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1620506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1621506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1622506f1d07SSam Ravnborg 1623506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1624506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1625506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1626506f1d07SSam Ravnborg 1627506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1628506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1629506f1d07SSam Ravnborg 16307225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1631506f1d07SSam Ravnborg 163295ffa243SYinghai Luconfig MTRR_SANITIZER 16332ffb3501SYinghai Lu def_bool y 163495ffa243SYinghai Lu prompt "MTRR cleanup support" 163595ffa243SYinghai Lu depends on MTRR 16368f9ca475SIngo Molnar ---help--- 1637aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1638aba3728cSThomas Gleixner add writeback entries. 163995ffa243SYinghai Lu 1640aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1641692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1642aba3728cSThomas Gleixner mtrr_chunk_size. 164395ffa243SYinghai Lu 16442ffb3501SYinghai Lu If unsure, say Y. 164595ffa243SYinghai Lu 164695ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1647f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1648f5098d62SYinghai Lu range 0 1 1649f5098d62SYinghai Lu default "0" 165095ffa243SYinghai Lu depends on MTRR_SANITIZER 16518f9ca475SIngo Molnar ---help--- 1652f5098d62SYinghai Lu Enable mtrr cleanup default value 165395ffa243SYinghai Lu 165412031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 165512031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 165612031a62SYinghai Lu range 0 7 165712031a62SYinghai Lu default "1" 165812031a62SYinghai Lu depends on MTRR_SANITIZER 16598f9ca475SIngo Molnar ---help--- 166012031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1661aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 166212031a62SYinghai Lu 16632e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 16646fc108a0SJan Beulich def_bool y 16656a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 16662a8a2719SIngo Molnar depends on MTRR 16678f9ca475SIngo Molnar ---help--- 16682e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1669042b78e4SVenki Pallipadi 16702e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 16712e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 16722e5d9c85Svenkatesh.pallipadi@intel.com 16732e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1674042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 16752e5d9c85Svenkatesh.pallipadi@intel.com 16762e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 16772e5d9c85Svenkatesh.pallipadi@intel.com 167846cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 167946cf98cdSVenkatesh Pallipadi def_bool y 168046cf98cdSVenkatesh Pallipadi depends on X86_PAT 168146cf98cdSVenkatesh Pallipadi 1682628c6246SH. Peter Anvinconfig ARCH_RANDOM 1683628c6246SH. Peter Anvin def_bool y 1684628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1685628c6246SH. Peter Anvin ---help--- 1686628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1687628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1688628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1689628c6246SH. Peter Anvin secure hardware random number generator. 1690628c6246SH. Peter Anvin 169151ae4a2dSH. Peter Anvinconfig X86_SMAP 169251ae4a2dSH. Peter Anvin def_bool y 169351ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 169451ae4a2dSH. Peter Anvin ---help--- 169551ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 169651ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 169751ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 169851ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 169951ae4a2dSH. Peter Anvin 170051ae4a2dSH. Peter Anvin If unsure, say Y. 170151ae4a2dSH. Peter Anvin 170272e9b5feSDave Hansenconfig X86_INTEL_MPX 170372e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 170472e9b5feSDave Hansen def_bool n 170572e9b5feSDave Hansen depends on CPU_SUP_INTEL 170672e9b5feSDave Hansen ---help--- 170772e9b5feSDave Hansen MPX provides hardware features that can be used in 170872e9b5feSDave Hansen conjunction with compiler-instrumented code to check 170972e9b5feSDave Hansen memory references. It is designed to detect buffer 171072e9b5feSDave Hansen overflow or underflow bugs. 171172e9b5feSDave Hansen 171272e9b5feSDave Hansen This option enables running applications which are 171372e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 171472e9b5feSDave Hansen itself inside the kernel or to protect the kernel 171572e9b5feSDave Hansen against bad memory references. 171672e9b5feSDave Hansen 171772e9b5feSDave Hansen Enabling this option will make the kernel larger: 171872e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 171972e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 172072e9b5feSDave Hansen will increase the kernel memory overhead of each 172172e9b5feSDave Hansen process and adds some branches to paths used during 172272e9b5feSDave Hansen exec() and munmap(). 172372e9b5feSDave Hansen 172472e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 172572e9b5feSDave Hansen 172672e9b5feSDave Hansen If unsure, say N. 172772e9b5feSDave Hansen 1728506f1d07SSam Ravnborgconfig EFI 17299ba16087SJan Beulich bool "EFI runtime service support" 17305b83683fSHuang, Ying depends on ACPI 1731f6ce5002SSergey Vlasov select UCS2_STRING 1732022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1733506f1d07SSam Ravnborg ---help--- 17348b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1735506f1d07SSam Ravnborg available (such as the EFI variable services). 1736506f1d07SSam Ravnborg 17378b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 17388b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 17398b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 17408b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 17418b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 17428b2cb7a8SHuang, Ying platforms. 1743506f1d07SSam Ravnborg 1744291f3632SMatt Flemingconfig EFI_STUB 1745291f3632SMatt Fleming bool "EFI stub support" 1746b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 17477b2a583aSMatt Fleming select RELOCATABLE 1748291f3632SMatt Fleming ---help--- 1749291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1750291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1751291f3632SMatt Fleming 17524172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 17530c759662SMatt Fleming 17547d453eeeSMatt Flemingconfig EFI_MIXED 17557d453eeeSMatt Fleming bool "EFI mixed-mode support" 17567d453eeeSMatt Fleming depends on EFI_STUB && X86_64 17577d453eeeSMatt Fleming ---help--- 17587d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 17597d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 17607d453eeeSMatt Fleming mode. 17617d453eeeSMatt Fleming 17627d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 17637d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 17647d453eeeSMatt Fleming the EFI handover protocol must be used. 17657d453eeeSMatt Fleming 17667d453eeeSMatt Fleming If unsure, say N. 17677d453eeeSMatt Fleming 1768506f1d07SSam Ravnborgconfig SECCOMP 17693c2362e6SHarvey Harrison def_bool y 17703c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 17718f9ca475SIngo Molnar ---help--- 1772506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1773506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1774506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1775506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1776506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1777506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 17789c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1779506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1780506f1d07SSam Ravnborg defined by each seccomp mode. 1781506f1d07SSam Ravnborg 1782506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1783506f1d07SSam Ravnborg 1784506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1785506f1d07SSam Ravnborg 1786506f1d07SSam Ravnborgconfig KEXEC 1787506f1d07SSam Ravnborg bool "kexec system call" 17882965faa5SDave Young select KEXEC_CORE 17898f9ca475SIngo Molnar ---help--- 1790506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1791506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1792506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1793506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1794506f1d07SSam Ravnborg 1795506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1796506f1d07SSam Ravnborg 1797506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1798506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1799bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1800bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1801bf220695SGeert Uytterhoeven made. 1802506f1d07SSam Ravnborg 180374ca317cSVivek Goyalconfig KEXEC_FILE 180474ca317cSVivek Goyal bool "kexec file based system call" 18052965faa5SDave Young select KEXEC_CORE 180674ca317cSVivek Goyal select BUILD_BIN2C 180774ca317cSVivek Goyal depends on X86_64 180874ca317cSVivek Goyal depends on CRYPTO=y 180974ca317cSVivek Goyal depends on CRYPTO_SHA256=y 181074ca317cSVivek Goyal ---help--- 181174ca317cSVivek Goyal This is new version of kexec system call. This system call is 181274ca317cSVivek Goyal file based and takes file descriptors as system call argument 181374ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 181474ca317cSVivek Goyal accepted by previous system call. 181574ca317cSVivek Goyal 18168e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 18178e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 181874ca317cSVivek Goyal depends on KEXEC_FILE 18198e7d8381SVivek Goyal ---help--- 18208e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1821d8eb8940SBorislav Petkov the kexec_file_load() syscall. 18228e7d8381SVivek Goyal 1823d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1824d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1825d8eb8940SBorislav Petkov loaded in order for this to work. 18268e7d8381SVivek Goyal 18278e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 18288e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 18298e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 18308e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 18318e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 18328e7d8381SVivek Goyal ---help--- 18338e7d8381SVivek Goyal Enable bzImage signature verification support. 18348e7d8381SVivek Goyal 1835506f1d07SSam Ravnborgconfig CRASH_DUMP 183604b69447SPavel Machek bool "kernel crash dumps" 1837506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 18388f9ca475SIngo Molnar ---help--- 1839506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1840506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1841506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1842506f1d07SSam Ravnborg a specially reserved region and then later executed after 1843506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1844506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1845506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1846506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1847506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1848506f1d07SSam Ravnborg 18493ab83521SHuang Yingconfig KEXEC_JUMP 18506ea30386SKees Cook bool "kexec jump" 1851fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 18528f9ca475SIngo Molnar ---help--- 185389081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 185489081d17SHuang Ying code in physical address mode via KEXEC 18553ab83521SHuang Ying 1856506f1d07SSam Ravnborgconfig PHYSICAL_START 18576a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1858ceefccc9SH. Peter Anvin default "0x1000000" 18598f9ca475SIngo Molnar ---help--- 1860506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1861506f1d07SSam Ravnborg 1862506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1863506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1864506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1865506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1866506f1d07SSam Ravnborg address. 1867506f1d07SSam Ravnborg 1868506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1869506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1870506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1871506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1872506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1873506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1874506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1875506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1876506f1d07SSam Ravnborg 1877ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 1878ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 1879ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1880ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 1881ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 1882ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 1883ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 1884ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 1885ceefccc9SH. Peter Anvin for more details about crash dumps. 1886506f1d07SSam Ravnborg 1887506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 1888506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 1889506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 1890506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 1891506f1d07SSam Ravnborg is present because there are users out there who continue to use 1892506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 1893506f1d07SSam Ravnborg line. 1894506f1d07SSam Ravnborg 1895506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1896506f1d07SSam Ravnborg 1897506f1d07SSam Ravnborgconfig RELOCATABLE 189826717808SH. Peter Anvin bool "Build a relocatable kernel" 189926717808SH. Peter Anvin default y 19008f9ca475SIngo Molnar ---help--- 1901506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 1902506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 1903506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 1904506f1d07SSam Ravnborg but are discarded at runtime. 1905506f1d07SSam Ravnborg 1906506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 1907506f1d07SSam Ravnborg must live at a different physical address than the primary 1908506f1d07SSam Ravnborg kernel. 1909506f1d07SSam Ravnborg 1910506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1911506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 19128ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 1913506f1d07SSam Ravnborg 19148ab3820fSKees Cookconfig RANDOMIZE_BASE 19158ab3820fSKees Cook bool "Randomize the address of the kernel image" 19168ab3820fSKees Cook depends on RELOCATABLE 19178ab3820fSKees Cook default n 19188ab3820fSKees Cook ---help--- 19198ab3820fSKees Cook Randomizes the physical and virtual address at which the 19208ab3820fSKees Cook kernel image is decompressed, as a security feature that 19218ab3820fSKees Cook deters exploit attempts relying on knowledge of the location 19228ab3820fSKees Cook of kernel internals. 19238ab3820fSKees Cook 1924a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 1925a653f356SKees Cook supported. If RDTSC is supported, it is used as well. If 1926a653f356SKees Cook neither RDRAND nor RDTSC are supported, then randomness is 1927a653f356SKees Cook read from the i8254 timer. 19288ab3820fSKees Cook 19298ab3820fSKees Cook The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1930a653f356SKees Cook and aligned according to PHYSICAL_ALIGN. Since the kernel is 1931a653f356SKees Cook built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1932a653f356SKees Cook minimum of 2MiB, only 10 bits of entropy is theoretically 1933a653f356SKees Cook possible. At best, due to page table layouts, 64-bit can use 1934a653f356SKees Cook 9 bits of entropy and 32-bit uses 8 bits. 19358ab3820fSKees Cook 1936da2b6fb9SKees Cook If unsure, say N. 1937da2b6fb9SKees Cook 19388ab3820fSKees Cookconfig RANDOMIZE_BASE_MAX_OFFSET 1939da2b6fb9SKees Cook hex "Maximum kASLR offset allowed" if EXPERT 19408ab3820fSKees Cook depends on RANDOMIZE_BASE 19416145cfe3SKees Cook range 0x0 0x20000000 if X86_32 19426145cfe3SKees Cook default "0x20000000" if X86_32 19436145cfe3SKees Cook range 0x0 0x40000000 if X86_64 19446145cfe3SKees Cook default "0x40000000" if X86_64 19458ab3820fSKees Cook ---help--- 1946da2b6fb9SKees Cook The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1947da2b6fb9SKees Cook memory is used to determine the maximal offset in bytes that will 1948da2b6fb9SKees Cook be applied to the kernel when kernel Address Space Layout 1949da2b6fb9SKees Cook Randomization (kASLR) is active. This must be a multiple of 1950da2b6fb9SKees Cook PHYSICAL_ALIGN. 19516145cfe3SKees Cook 1952da2b6fb9SKees Cook On 32-bit this is limited to 512MiB by page table layouts. The 1953da2b6fb9SKees Cook default is 512MiB. 19546145cfe3SKees Cook 19556145cfe3SKees Cook On 64-bit this is limited by how the kernel fixmap page table is 1956da2b6fb9SKees Cook positioned, so this cannot be larger than 1GiB currently. Without 1957da2b6fb9SKees Cook RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1958da2b6fb9SKees Cook and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1959da2b6fb9SKees Cook modules area will shrink to compensate, up to the current maximum 1960da2b6fb9SKees Cook 1GiB to 1GiB split. The default is 1GiB. 1961da2b6fb9SKees Cook 1962da2b6fb9SKees Cook If unsure, leave at the default value. 19638ab3820fSKees Cook 19648ab3820fSKees Cook# Relocation on x86 needs some additional build support 1965845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 1966845adf72SH. Peter Anvin def_bool y 19678ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1968845adf72SH. Peter Anvin 1969506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 1970a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 19718ab3820fSKees Cook default "0x200000" 1972a0215061SKees Cook range 0x2000 0x1000000 if X86_32 1973a0215061SKees Cook range 0x200000 0x1000000 if X86_64 19748f9ca475SIngo Molnar ---help--- 1975506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 1976506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 1977506f1d07SSam Ravnborg address which meets above alignment restriction. 1978506f1d07SSam Ravnborg 1979506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1980506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1981506f1d07SSam Ravnborg address aligned to above value and run from there. 1982506f1d07SSam Ravnborg 1983506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1984506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1985506f1d07SSam Ravnborg load address and decompress itself to the address it has been 1986506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 1987506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 1988506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 1989506f1d07SSam Ravnborg above alignment restrictions. 1990506f1d07SSam Ravnborg 1991a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 1992a0215061SKees Cook this value must be a multiple of 0x200000. 1993a0215061SKees Cook 1994506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1995506f1d07SSam Ravnborg 1996506f1d07SSam Ravnborgconfig HOTPLUG_CPU 19977c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 199840b31360SStephen Rothwell depends on SMP 1999506f1d07SSam Ravnborg ---help--- 20007c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 20017c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 20027c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 20037c13e6a3SDimitri Sivanich automatically on SMP systems. ) 20047c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2005506f1d07SSam Ravnborg 200680aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 200780aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 200880aa1dffSFenghua Yu default n 20092c922cd0SKees Cook depends on HOTPLUG_CPU 201080aa1dffSFenghua Yu ---help--- 201180aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 201280aa1dffSFenghua Yu 201380aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 201480aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 201580aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 201680aa1dffSFenghua Yu 201780aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 201880aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 201980aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 202080aa1dffSFenghua Yu 202180aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 202280aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 202380aa1dffSFenghua Yu 202480aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 202580aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 202680aa1dffSFenghua Yu be other CPU0 dependencies. 202780aa1dffSFenghua Yu 202880aa1dffSFenghua Yu Please make sure the dependencies are under your control before 202980aa1dffSFenghua Yu you enable this feature. 203080aa1dffSFenghua Yu 203180aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 203280aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 203380aa1dffSFenghua Yu parameter cpu0_hotplug. 203480aa1dffSFenghua Yu 2035a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2036a71c8bc5SFenghua Yu def_bool n 2037a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 20382c922cd0SKees Cook depends on HOTPLUG_CPU 2039a71c8bc5SFenghua Yu ---help--- 2040a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2041a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2042a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2043a71c8bc5SFenghua Yu 2044a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2045a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2046a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2047a71c8bc5SFenghua Yu 2048a71c8bc5SFenghua Yu If unsure, say N. 2049a71c8bc5SFenghua Yu 2050506f1d07SSam Ravnborgconfig COMPAT_VDSO 2051b0b49f26SAndy Lutomirski def_bool n 2052b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2053af65d648SRoland McGrath depends on X86_32 || IA32_EMULATION 20548f9ca475SIngo Molnar ---help--- 2055b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2056b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2057b0b49f26SAndy Lutomirski indicated in its segment table. 2058e84446deSRandy Dunlap 2059b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2060b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2061b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2062b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2063b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2064506f1d07SSam Ravnborg 2065b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2066b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2067b0b49f26SAndy Lutomirski 2068b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2069b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2070b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2071b0b49f26SAndy Lutomirski 2072b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2073b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2074506f1d07SSam Ravnborg 20753dc33bd3SKees Cookchoice 20763dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 20773dc33bd3SKees Cook depends on X86_64 20783dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 20793dc33bd3SKees Cook help 20803dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 20813dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 20823dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 20833dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 20843dc33bd3SKees Cook 20853dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 20863dc33bd3SKees Cook line parameter vsyscall=[native|emulate|none]. 20873dc33bd3SKees Cook 20883dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 20893dc33bd3SKees Cook static binaries, you can say None without a performance penalty 20903dc33bd3SKees Cook to improve security. 20913dc33bd3SKees Cook 20923dc33bd3SKees Cook If unsure, select "Emulate". 20933dc33bd3SKees Cook 20943dc33bd3SKees Cook config LEGACY_VSYSCALL_NATIVE 20953dc33bd3SKees Cook bool "Native" 20963dc33bd3SKees Cook help 20973dc33bd3SKees Cook Actual executable code is located in the fixed vsyscall 20983dc33bd3SKees Cook address mapping, implementing time() efficiently. Since 20993dc33bd3SKees Cook this makes the mapping executable, it can be used during 21003dc33bd3SKees Cook security vulnerability exploitation (traditionally as 21013dc33bd3SKees Cook ROP gadgets). This configuration is not recommended. 21023dc33bd3SKees Cook 21033dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 21043dc33bd3SKees Cook bool "Emulate" 21053dc33bd3SKees Cook help 21063dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 21073dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 21083dc33bd3SKees Cook non-executable, but it still contains known contents, 21093dc33bd3SKees Cook which could be used in certain rare security vulnerability 21103dc33bd3SKees Cook exploits. This configuration is recommended when userspace 21113dc33bd3SKees Cook still uses the vsyscall area. 21123dc33bd3SKees Cook 21133dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 21143dc33bd3SKees Cook bool "None" 21153dc33bd3SKees Cook help 21163dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 21173dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 21183dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 21193dc33bd3SKees Cook will be reported to dmesg, so that either old or 21203dc33bd3SKees Cook malicious userspace programs can be identified. 21213dc33bd3SKees Cook 21223dc33bd3SKees Cookendchoice 21233dc33bd3SKees Cook 2124516cbf37STim Birdconfig CMDLINE_BOOL 2125516cbf37STim Bird bool "Built-in kernel command line" 21268f9ca475SIngo Molnar ---help--- 2127516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2128516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2129516cbf37STim Bird necessary or convenient to provide some or all of the 2130516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2131516cbf37STim Bird to not rely on the boot loader to provide them.) 2132516cbf37STim Bird 2133516cbf37STim Bird To compile command line arguments into the kernel, 2134516cbf37STim Bird set this option to 'Y', then fill in the 213569711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2136516cbf37STim Bird 2137516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2138516cbf37STim Bird should leave this option set to 'N'. 2139516cbf37STim Bird 2140516cbf37STim Birdconfig CMDLINE 2141516cbf37STim Bird string "Built-in kernel command string" 2142516cbf37STim Bird depends on CMDLINE_BOOL 2143516cbf37STim Bird default "" 21448f9ca475SIngo Molnar ---help--- 2145516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2146516cbf37STim Bird image and used at boot time. If the boot loader provides a 2147516cbf37STim Bird command line at boot time, it is appended to this string to 2148516cbf37STim Bird form the full kernel command line, when the system boots. 2149516cbf37STim Bird 2150516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2151516cbf37STim Bird change this behavior. 2152516cbf37STim Bird 2153516cbf37STim Bird In most cases, the command line (whether built-in or provided 2154516cbf37STim Bird by the boot loader) should specify the device for the root 2155516cbf37STim Bird file system. 2156516cbf37STim Bird 2157516cbf37STim Birdconfig CMDLINE_OVERRIDE 2158516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2159516cbf37STim Bird depends on CMDLINE_BOOL 21608f9ca475SIngo Molnar ---help--- 2161516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2162516cbf37STim Bird command line, and use ONLY the built-in command line. 2163516cbf37STim Bird 2164516cbf37STim Bird This is used to work around broken boot loaders. This should 2165516cbf37STim Bird be set to 'N' under normal conditions. 2166516cbf37STim Bird 2167a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2168a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2169a5b9e5a2SAndy Lutomirski default y 2170a5b9e5a2SAndy Lutomirski ---help--- 2171a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2172a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2173a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2174a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2175a5b9e5a2SAndy Lutomirski threading libraries. 2176a5b9e5a2SAndy Lutomirski 2177a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2178a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2179a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2180a5b9e5a2SAndy Lutomirski 2181a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2182a5b9e5a2SAndy Lutomirski 2183b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2184b700e7f0SSeth Jennings 2185506f1d07SSam Ravnborgendmenu 2186506f1d07SSam Ravnborg 2187506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2188506f1d07SSam Ravnborg def_bool y 2189506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2190506f1d07SSam Ravnborg 219135551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 219235551053SGary Hade def_bool y 219335551053SGary Hade depends on MEMORY_HOTPLUG 219435551053SGary Hade 2195e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2196645a7919STejun Heo def_bool y 2197e534c7c5SLee Schermerhorn depends on NUMA 2198e534c7c5SLee Schermerhorn 21999491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 22009491846fSKirill A. Shutemov def_bool y 22019491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 22029491846fSKirill A. Shutemov 2203c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2204c177c81eSNaoya Horiguchi def_bool y 2205c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2206c177c81eSNaoya Horiguchi 2207da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2208e279b6c1SSam Ravnborg 2209e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 22103c2362e6SHarvey Harrison def_bool y 2211e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2212e279b6c1SSam Ravnborg 2213e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2214e279b6c1SSam Ravnborg 2215e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2216e279b6c1SSam Ravnborg 2217efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2218efafc8b2SFeng Tang 2219a6b68076SAndi Kleenconfig X86_APM_BOOT 22206fc108a0SJan Beulich def_bool y 2221282e5aabSPaul Bolle depends on APM 2222a6b68076SAndi Kleen 2223e279b6c1SSam Ravnborgmenuconfig APM 2224e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2225efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2226e279b6c1SSam Ravnborg ---help--- 2227e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2228e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2229e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2230e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2231e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2232e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2233e279b6c1SSam Ravnborg 2234e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2235e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2236e279b6c1SSam Ravnborg 2237e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2238e279b6c1SSam Ravnborg machines with more than one CPU. 2239e279b6c1SSam Ravnborg 2240e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 22412dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 22422dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2243e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2244e279b6c1SSam Ravnborg 2245e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2246e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2247e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2248e279b6c1SSam Ravnborg 2249e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2250e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2251e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2252e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2253e279b6c1SSam Ravnborg 2254e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2255e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2256e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2257e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2258e279b6c1SSam Ravnborg APM in your BIOS). 2259e279b6c1SSam Ravnborg 2260e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2261e279b6c1SSam Ravnborg "weird" problems: 2262e279b6c1SSam Ravnborg 2263e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2264e279b6c1SSam Ravnborg enabled. 2265e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2266e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2267e279b6c1SSam Ravnborg the "no387" option to the kernel 2268e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2269e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2270e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2271e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2272e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2273e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2274e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2275e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2276e279b6c1SSam Ravnborg 11) exchange RAM chips 2277e279b6c1SSam Ravnborg 12) exchange the motherboard. 2278e279b6c1SSam Ravnborg 2279e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2280e279b6c1SSam Ravnborg module will be called apm. 2281e279b6c1SSam Ravnborg 2282e279b6c1SSam Ravnborgif APM 2283e279b6c1SSam Ravnborg 2284e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2285e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 22868f9ca475SIngo Molnar ---help--- 2287e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2288e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2289e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2290e279b6c1SSam Ravnborg 2291e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2292e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2293e279b6c1SSam Ravnborg ---help--- 2294e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2295e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2296e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2297e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2298e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2299e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2300e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2301e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2302e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2303e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2304e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2305e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2306e279b6c1SSam Ravnborg this feature. 2307e279b6c1SSam Ravnborg 2308e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2309dd8af076SLen Brown depends on CPU_IDLE 2310e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 23118f9ca475SIngo Molnar ---help--- 2312e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2313e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2314e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2315e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2316e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2317e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2318e279b6c1SSam Ravnborg this option does nothing.) 2319e279b6c1SSam Ravnborg 2320e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2321e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 23228f9ca475SIngo Molnar ---help--- 2323e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2324e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2325e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2326e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2327e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2328e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2329e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2330e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2331e279b6c1SSam Ravnborg especially if you are using gpm. 2332e279b6c1SSam Ravnborg 2333e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2334e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 23358f9ca475SIngo Molnar ---help--- 2336e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2337e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2338e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2339e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2340e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2341e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2342e279b6c1SSam Ravnborg 2343e279b6c1SSam Ravnborgendif # APM 2344e279b6c1SSam Ravnborg 2345bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2346e279b6c1SSam Ravnborg 2347e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2348e279b6c1SSam Ravnborg 234927471fdbSAndy Henroidsource "drivers/idle/Kconfig" 235027471fdbSAndy Henroid 2351e279b6c1SSam Ravnborgendmenu 2352e279b6c1SSam Ravnborg 2353e279b6c1SSam Ravnborg 2354e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2355e279b6c1SSam Ravnborg 2356e279b6c1SSam Ravnborgconfig PCI 23571ac97018SIngo Molnar bool "PCI support" 23581c858087SAdrian Bunk default y 23598f9ca475SIngo Molnar ---help--- 2360e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2361e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2362e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2363e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2364e279b6c1SSam Ravnborg 2365e279b6c1SSam Ravnborgchoice 2366e279b6c1SSam Ravnborg prompt "PCI access mode" 2367efefa6f6SIngo Molnar depends on X86_32 && PCI 2368e279b6c1SSam Ravnborg default PCI_GOANY 2369e279b6c1SSam Ravnborg ---help--- 2370e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2371e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2372e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2373e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2374e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2375e279b6c1SSam Ravnborg 2376e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2377e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2378e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2379e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2380e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2381e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2382e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2383e279b6c1SSam Ravnborg 2384e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2385e279b6c1SSam Ravnborg bool "BIOS" 2386e279b6c1SSam Ravnborg 2387e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2388e279b6c1SSam Ravnborg bool "MMConfig" 2389e279b6c1SSam Ravnborg 2390e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2391e279b6c1SSam Ravnborg bool "Direct" 2392e279b6c1SSam Ravnborg 23933ef0e1f8SAndres Salomonconfig PCI_GOOLPC 239476fb6570SDaniel Drake bool "OLPC XO-1" 23953ef0e1f8SAndres Salomon depends on OLPC 23963ef0e1f8SAndres Salomon 23972bdd1b03SAndres Salomonconfig PCI_GOANY 23982bdd1b03SAndres Salomon bool "Any" 23992bdd1b03SAndres Salomon 2400e279b6c1SSam Ravnborgendchoice 2401e279b6c1SSam Ravnborg 2402e279b6c1SSam Ravnborgconfig PCI_BIOS 24033c2362e6SHarvey Harrison def_bool y 2404efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2405e279b6c1SSam Ravnborg 2406e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2407e279b6c1SSam Ravnborgconfig PCI_DIRECT 24083c2362e6SHarvey Harrison def_bool y 24090aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2410e279b6c1SSam Ravnborg 2411e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 24123c2362e6SHarvey Harrison def_bool y 24135f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2414e279b6c1SSam Ravnborg 24153ef0e1f8SAndres Salomonconfig PCI_OLPC 24162bdd1b03SAndres Salomon def_bool y 24172bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 24183ef0e1f8SAndres Salomon 2419b5401a96SAlex Nixonconfig PCI_XEN 2420b5401a96SAlex Nixon def_bool y 2421b5401a96SAlex Nixon depends on PCI && XEN 2422b5401a96SAlex Nixon select SWIOTLB_XEN 2423b5401a96SAlex Nixon 2424e279b6c1SSam Ravnborgconfig PCI_DOMAINS 24253c2362e6SHarvey Harrison def_bool y 2426e279b6c1SSam Ravnborg depends on PCI 2427e279b6c1SSam Ravnborg 2428e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2429e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2430e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2431e279b6c1SSam Ravnborg 24323f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 24336a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 24346ea30386SKees Cook depends on PCI 24353f6ea84aSIra W. Snyder help 24363f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 24373f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 24383f6ea84aSIra W. Snyder not have ACPI. 24393f6ea84aSIra W. Snyder 244064a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 244164a5fed6SBjorn Helgaas is known to be incomplete. 244264a5fed6SBjorn Helgaas 244364a5fed6SBjorn Helgaas You should say N unless you know you need this. 244464a5fed6SBjorn Helgaas 2445e279b6c1SSam Ravnborgsource "drivers/pci/pcie/Kconfig" 2446e279b6c1SSam Ravnborg 2447e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2448e279b6c1SSam Ravnborg 24491c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2450e279b6c1SSam Ravnborgconfig ISA_DMA_API 24511c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 24521c00f016SDavid Rientjes default y 24531c00f016SDavid Rientjes help 24541c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 24551c00f016SDavid Rientjes If unsure, say Y. 2456e279b6c1SSam Ravnborg 2457e279b6c1SSam Ravnborgif X86_32 2458e279b6c1SSam Ravnborg 2459e279b6c1SSam Ravnborgconfig ISA 2460e279b6c1SSam Ravnborg bool "ISA support" 24618f9ca475SIngo Molnar ---help--- 2462e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2463e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2464e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2465e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2466e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2467e279b6c1SSam Ravnborg 2468e279b6c1SSam Ravnborgconfig EISA 2469e279b6c1SSam Ravnborg bool "EISA support" 2470e279b6c1SSam Ravnborg depends on ISA 2471e279b6c1SSam Ravnborg ---help--- 2472e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2473e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2474e279b6c1SSam Ravnborg 2475e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2476e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2477e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2478e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2479e279b6c1SSam Ravnborg 2480e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2481e279b6c1SSam Ravnborg 2482e279b6c1SSam Ravnborg Otherwise, say N. 2483e279b6c1SSam Ravnborg 2484e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2485e279b6c1SSam Ravnborg 2486e279b6c1SSam Ravnborgconfig SCx200 2487e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 24888f9ca475SIngo Molnar ---help--- 2489e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2490e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2491e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2492e279b6c1SSam Ravnborg for other scx200_* drivers. 2493e279b6c1SSam Ravnborg 2494e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2495e279b6c1SSam Ravnborg 2496e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2497e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2498592913ecSJohn Stultz depends on SCx200 2499e279b6c1SSam Ravnborg default y 25008f9ca475SIngo Molnar ---help--- 2501e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2502e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2503e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2504e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2505e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2506e279b6c1SSam Ravnborg 25073ef0e1f8SAndres Salomonconfig OLPC 25083ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 250954008979SThomas Gleixner depends on !X86_PAE 25103c554946SAndres Salomon select GPIOLIB 2511dc3119e7SThomas Gleixner select OF 251245bb1674SDaniel Drake select OF_PROMTREE 2513b4e51854SGrant Likely select IRQ_DOMAIN 25148f9ca475SIngo Molnar ---help--- 25153ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 25163ef0e1f8SAndres Salomon XO hardware. 25173ef0e1f8SAndres Salomon 2518a3128588SDaniel Drakeconfig OLPC_XO1_PM 2519a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 252097c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2521a3128588SDaniel Drake select MFD_CORE 2522bf1ebf00SDaniel Drake ---help--- 252397c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2524bf1ebf00SDaniel Drake 2525cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2526cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2527cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2528cfee9597SDaniel Drake ---help--- 2529cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2530cfee9597SDaniel Drake programmable wakeup source. 2531cfee9597SDaniel Drake 25327feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 25337feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2534d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2535ed8e47feSRandy Dunlap depends on INPUT=y 2536d8d01a63SDaniel Drake select POWER_SUPPLY 25377feda8e9SDaniel Drake select GPIO_CS5535 25387feda8e9SDaniel Drake select MFD_CORE 25397feda8e9SDaniel Drake ---help--- 25407feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 25417bc74b3dSDaniel Drake - EC-driven system wakeups 25427feda8e9SDaniel Drake - Power button 25437bc74b3dSDaniel Drake - Ebook switch 25442cf2baeaSDaniel Drake - Lid switch 2545e1040ac6SDaniel Drake - AC adapter status updates 2546e1040ac6SDaniel Drake - Battery status updates 25477feda8e9SDaniel Drake 2548a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2549a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2550d8d01a63SDaniel Drake depends on OLPC && ACPI 2551d8d01a63SDaniel Drake select POWER_SUPPLY 2552a0f30f59SDaniel Drake ---help--- 2553a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2554a0f30f59SDaniel Drake - EC-driven system wakeups 2555a0f30f59SDaniel Drake - AC adapter status updates 2556a0f30f59SDaniel Drake - Battery status updates 2557e279b6c1SSam Ravnborg 2558d4f3e350SEd Wildgooseconfig ALIX 2559d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2560d4f3e350SEd Wildgoose select GPIOLIB 2561d4f3e350SEd Wildgoose ---help--- 2562d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2563d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2564d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2565d4f3e350SEd Wildgoose get added here. 2566d4f3e350SEd Wildgoose 2567d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2568d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2569d4f3e350SEd Wildgoose 2570d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2571d4f3e350SEd Wildgoose 2572da4e3302SPhilip Prindevilleconfig NET5501 2573da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2574da4e3302SPhilip Prindeville select GPIOLIB 2575da4e3302SPhilip Prindeville ---help--- 2576da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2577da4e3302SPhilip Prindeville 25783197059aSPhilip A. Prindevilleconfig GEOS 25793197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 25803197059aSPhilip A. Prindeville select GPIOLIB 25813197059aSPhilip A. Prindeville depends on DMI 25823197059aSPhilip A. Prindeville ---help--- 25833197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 25843197059aSPhilip A. Prindeville 25857d029125SVivien Didelotconfig TS5500 25867d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 25877d029125SVivien Didelot depends on MELAN 25887d029125SVivien Didelot select CHECK_SIGNATURE 25897d029125SVivien Didelot select NEW_LEDS 25907d029125SVivien Didelot select LEDS_CLASS 25917d029125SVivien Didelot ---help--- 25927d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 25937d029125SVivien Didelot 2594e279b6c1SSam Ravnborgendif # X86_32 2595e279b6c1SSam Ravnborg 259623ac4ae8SAndreas Herrmannconfig AMD_NB 2597e279b6c1SSam Ravnborg def_bool y 25980e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2599e279b6c1SSam Ravnborg 2600e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2601e279b6c1SSam Ravnborg 2602e279b6c1SSam Ravnborgsource "drivers/pci/hotplug/Kconfig" 2603e279b6c1SSam Ravnborg 2604388b78adSAlexandre Bounineconfig RAPIDIO 2605fdf90abcSAlexandre Bounine tristate "RapidIO support" 2606388b78adSAlexandre Bounine depends on PCI 2607388b78adSAlexandre Bounine default n 2608388b78adSAlexandre Bounine help 2609fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2610388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2611388b78adSAlexandre Bounine 2612388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2613388b78adSAlexandre Bounine 2614e3263ab3SDavid Herrmannconfig X86_SYSFB 2615e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2616e3263ab3SDavid Herrmann help 2617e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2618e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2619e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2620e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2621e3263ab3SDavid Herrmann to x86. 2622e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2623e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2624e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2625e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2626e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2627e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2628e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2629e3263ab3SDavid Herrmann 2630e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2631e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2632e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2633e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2634e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2635e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2636e3263ab3SDavid Herrmann incompatible with simplefb. 2637e3263ab3SDavid Herrmann 2638e3263ab3SDavid Herrmann If unsure, say Y. 2639e3263ab3SDavid Herrmann 2640e279b6c1SSam Ravnborgendmenu 2641e279b6c1SSam Ravnborg 2642e279b6c1SSam Ravnborg 2643e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2644e279b6c1SSam Ravnborg 2645e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2646e279b6c1SSam Ravnborg 2647e279b6c1SSam Ravnborgconfig IA32_EMULATION 2648e279b6c1SSam Ravnborg bool "IA32 Emulation" 2649e279b6c1SSam Ravnborg depends on X86_64 2650d1603990SRandy Dunlap select BINFMT_ELF 2651a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 26523bead553SBrian Gerst select ARCH_WANT_OLD_COMPAT_IPC 26538f9ca475SIngo Molnar ---help--- 26545fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 26555fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 26565fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2657e279b6c1SSam Ravnborg 2658e279b6c1SSam Ravnborgconfig IA32_AOUT 2659e279b6c1SSam Ravnborg tristate "IA32 a.out support" 26606b213e1bSDavid Woodhouse depends on IA32_EMULATION 26618f9ca475SIngo Molnar ---help--- 2662e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2663e279b6c1SSam Ravnborg 26640bf62763SH. Peter Anvinconfig X86_X32 26656ea30386SKees Cook bool "x32 ABI for 64-bit mode" 26669b54050bSBrian Gerst depends on X86_64 26675fd92e65SH. J. Lu ---help--- 26685fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 26695fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 26705fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 26715fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 26725fd92e65SH. J. Lu 26735fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 26745fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 26755fd92e65SH. J. Lu option set. 26765fd92e65SH. J. Lu 2677e279b6c1SSam Ravnborgconfig COMPAT 26783c2362e6SHarvey Harrison def_bool y 26790bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2680e279b6c1SSam Ravnborg 26813120e25eSJan Beulichif COMPAT 2682e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 26833120e25eSJan Beulich def_bool y 2684e279b6c1SSam Ravnborg 2685e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 26863c2362e6SHarvey Harrison def_bool y 26873120e25eSJan Beulich depends on SYSVIPC 2688e279b6c1SSam Ravnborg 2689ee009e4aSDavid Howellsconfig KEYS_COMPAT 26903120e25eSJan Beulich def_bool y 26913120e25eSJan Beulich depends on KEYS 26923120e25eSJan Beulichendif 2693ee009e4aSDavid Howells 2694e279b6c1SSam Ravnborgendmenu 2695e279b6c1SSam Ravnborg 2696e279b6c1SSam Ravnborg 2697e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2698e5beae16SKeith Packard def_bool y 2699e5beae16SKeith Packard depends on X86_32 2700e5beae16SKeith Packard 27014692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 27024692d77fSAlessandro Rubini bool 270383125a3aSAlessandro Rubini depends on X86_64 || STA2X11 27044692d77fSAlessandro Rubini 2705f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2706f7219a53SAlessandro Rubini bool 270783125a3aSAlessandro Rubini depends on STA2X11 2708f7219a53SAlessandro Rubini 270993e5eaddSLi, Aubreyconfig PMC_ATOM 271093e5eaddSLi, Aubrey def_bool y 271193e5eaddSLi, Aubrey depends on PCI 271293e5eaddSLi, Aubrey 2713185a383aSKeith Buschconfig VMD 2714185a383aSKeith Busch depends on PCI_MSI 2715185a383aSKeith Busch tristate "Volume Management Device Driver" 2716185a383aSKeith Busch default N 2717185a383aSKeith Busch ---help--- 2718185a383aSKeith Busch Adds support for the Intel Volume Management Device (VMD). VMD is a 2719185a383aSKeith Busch secondary PCI host bridge that allows PCI Express root ports, 2720185a383aSKeith Busch and devices attached to them, to be removed from the default 2721185a383aSKeith Busch PCI domain and placed within the VMD domain. This provides 2722185a383aSKeith Busch more bus resources than are otherwise possible with a 2723185a383aSKeith Busch single domain. If you know your system provides one of these and 2724185a383aSKeith Busch has devices attached to it, say Y; if you are not sure, say N. 2725185a383aSKeith Busch 2726e279b6c1SSam Ravnborgsource "net/Kconfig" 2727e279b6c1SSam Ravnborg 2728e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2729e279b6c1SSam Ravnborg 2730e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2731e279b6c1SSam Ravnborg 2732e279b6c1SSam Ravnborgsource "fs/Kconfig" 2733e279b6c1SSam Ravnborg 2734e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2735e279b6c1SSam Ravnborg 2736e279b6c1SSam Ravnborgsource "security/Kconfig" 2737e279b6c1SSam Ravnborg 2738e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2739e279b6c1SSam Ravnborg 2740edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2741edf88417SAvi Kivity 2742e279b6c1SSam Ravnborgsource "lib/Kconfig" 2743