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 12341c787eSIngo Molnar # Options that are inherently 32-bit kernel only: 13341c787eSIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION 14341c787eSIngo Molnar select CLKSRC_I8253 15341c787eSIngo Molnar select CLONE_BACKWARDS 16341c787eSIngo Molnar select HAVE_AOUT 17341c787eSIngo Molnar select HAVE_GENERIC_DMA_COHERENT 18341c787eSIngo Molnar select MODULES_USE_ELF_REL 19341c787eSIngo Molnar select OLD_SIGACTION 20daa93fabSSam Ravnborg 21daa93fabSSam Ravnborgconfig X86_64 223120e25eSJan Beulich def_bool y 233120e25eSJan Beulich depends on 64BIT 24d94e0685SIngo Molnar # Options that are inherently 64-bit kernel only: 25e1073d1eSAneesh Kumar K.V select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA 26d94e0685SIngo Molnar select ARCH_SUPPORTS_INT128 27d94e0685SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF 28d94e0685SIngo Molnar select HAVE_ARCH_SOFT_DIRTY 29d94e0685SIngo Molnar select MODULES_USE_ELF_RELA 30d94e0685SIngo Molnar select X86_DEV_DMA_OPS 311032c0baSSam Ravnborg 32d94e0685SIngo Molnar# 33d94e0685SIngo Molnar# Arch settings 34d94e0685SIngo Molnar# 35d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 36d94e0685SIngo Molnar# ported to 32-bit as well. ) 37d94e0685SIngo Molnar# 388d5fffb9SSam Ravnborgconfig X86 393c2362e6SHarvey Harrison def_bool y 40c763ea26SIngo Molnar # 41c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 42c763ea26SIngo Molnar # 436471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 446e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 456471b825SIngo Molnar select ANON_INODES 466471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 476471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 4891dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 49fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5021266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 516471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5272d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 536974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 54957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 555c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 56c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 577b3d61ccSIngo Molnar # Causing hangs/crashes, see the commit that added this change for details. 587b3d61ccSIngo Molnar select ARCH_HAS_REFCOUNT if BROKEN 590aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 60d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 616471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 62ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 63ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 64c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 6565f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 666471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 676471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 6877fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 695e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 706471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 713b242c66SMel Gorman select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 726471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 736471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 746471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 756471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 76ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 77c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 7838d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 796471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 806471b825SIngo Molnar select CLKEVT_I8253 816471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 826471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 836471b825SIngo Molnar select DCACHE_WORD_ACCESS 8445471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 8545471cd9SLinus Torvalds select EDAC_SUPPORT 866471b825SIngo Molnar select GENERIC_CLOCKEVENTS 876471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 886471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 896471b825SIngo Molnar select GENERIC_CMOS_UPDATE 906471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 916471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 926471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 936471b825SIngo Molnar select GENERIC_IOMAP 94c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 95ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 966471b825SIngo Molnar select GENERIC_IRQ_PROBE 976471b825SIngo Molnar select GENERIC_IRQ_SHOW 986471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 996471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1006471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1016471b825SIngo Molnar select GENERIC_STRNLEN_USER 1026471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1037edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1046471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1056471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1066471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1076471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1086471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1096471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 1106471b825SIngo Molnar select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 1116471b825SIngo Molnar select HAVE_ARCH_KGDB 1126471b825SIngo Molnar select HAVE_ARCH_KMEMCHECK 1139e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1149e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1151b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1166471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 1176471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1186471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 119a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 120e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 121c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1226471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1236471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1246471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1256471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 126c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1276471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1286471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1296471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1306471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1319c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 132677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 13306aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 134c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 13558340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1365f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 137644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1386471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1396471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1406471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1416b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1420067f129SK.Prasad select HAVE_HW_BREAKPOINT 1436471b825SIngo Molnar select HAVE_IDE 1446471b825SIngo Molnar select HAVE_IOREMAP_PROT 1456471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1466471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1476471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1486471b825SIngo Molnar select HAVE_KERNEL_GZIP 1496471b825SIngo Molnar select HAVE_KERNEL_LZ4 1506471b825SIngo Molnar select HAVE_KERNEL_LZMA 1516471b825SIngo Molnar select HAVE_KERNEL_LZO 1526471b825SIngo Molnar select HAVE_KERNEL_XZ 1536471b825SIngo Molnar select HAVE_KPROBES 1546471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 1556471b825SIngo Molnar select HAVE_KRETPROBES 1566471b825SIngo Molnar select HAVE_KVM 1576471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1586471b825SIngo Molnar select HAVE_MEMBLOCK 1596471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1600102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 161ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 16242a0bb3fSPetr Mladek select HAVE_NMI 1636471b825SIngo Molnar select HAVE_OPROFILE 1646471b825SIngo Molnar select HAVE_OPTPROBES 1656471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1666471b825SIngo Molnar select HAVE_PERF_EVENTS 167c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 16892e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 169c5e63197SJiri Olsa select HAVE_PERF_REGS 170c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1719e52fc2bSVitaly Kuznetsov select HAVE_RCU_TABLE_FREE 1726471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 173*11af8474SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION 174c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1756471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1766471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1777c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 178c0185808SThomas Gleixner select IRQ_FORCED_THREADING 179df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1806471b825SIngo Molnar select PERF_EVENTS 1813195ef59SPrarit Bhargava select RTC_LIB 182d6faca40SArnd Bergmann select RTC_MC146818_LIB 1836471b825SIngo Molnar select SPARSE_IRQ 18483fe27eaSPranith Kumar select SRCU 1856471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 18615f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1876471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1886471b825SIngo Molnar select VIRT_TO_BUS 1896471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1907d8330a5SBalbir Singh 191ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1923120e25eSJan Beulich def_bool y 1933120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 194ba7e4d13SIngo Molnar 19551b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 19651b26adaSLinus Torvalds string 19751b26adaSLinus Torvalds default "elf32-i386" if X86_32 19851b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 19951b26adaSLinus Torvalds 20073531905SSam Ravnborgconfig ARCH_DEFCONFIG 201b9b39bfbSSam Ravnborg string 20273531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 20373531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 204b9b39bfbSSam Ravnborg 2058d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2063c2362e6SHarvey Harrison def_bool y 2078d5fffb9SSam Ravnborg 2088d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2093c2362e6SHarvey Harrison def_bool y 2108d5fffb9SSam Ravnborg 2118d5fffb9SSam Ravnborgconfig MMU 2123c2362e6SHarvey Harrison def_bool y 2138d5fffb9SSam Ravnborg 2149e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2159e08f57dSDaniel Cashman default 28 if 64BIT 2169e08f57dSDaniel Cashman default 8 2179e08f57dSDaniel Cashman 2189e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2199e08f57dSDaniel Cashman default 32 if 64BIT 2209e08f57dSDaniel Cashman default 16 2219e08f57dSDaniel Cashman 2229e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2239e08f57dSDaniel Cashman default 8 2249e08f57dSDaniel Cashman 2259e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2269e08f57dSDaniel Cashman default 16 2279e08f57dSDaniel Cashman 2288d5fffb9SSam Ravnborgconfig SBUS 2298d5fffb9SSam Ravnborg bool 2308d5fffb9SSam Ravnborg 2313bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2323120e25eSJan Beulich def_bool y 233a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2343bc4e459SFUJITA Tomonori 23518e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2364a14d84eSAndrew Morton def_bool y 23718e98307SFUJITA Tomonori 2388d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2393120e25eSJan Beulich def_bool y 2403120e25eSJan Beulich depends on ISA_DMA_API 2418d5fffb9SSam Ravnborg 2428d5fffb9SSam Ravnborgconfig GENERIC_BUG 2433c2362e6SHarvey Harrison def_bool y 2448d5fffb9SSam Ravnborg depends on BUG 245b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 246b93a531eSJan Beulich 247b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 248b93a531eSJan Beulich bool 2498d5fffb9SSam Ravnborg 2508d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2513c2362e6SHarvey Harrison def_bool y 2528d5fffb9SSam Ravnborg 2538d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2543120e25eSJan Beulich def_bool y 2553120e25eSJan Beulich depends on ISA_DMA_API 2568d5fffb9SSam Ravnborg 2571032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2583120e25eSJan Beulich def_bool y 2591032c0baSSam Ravnborg 2601032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2611032c0baSSam Ravnborg def_bool y 2621032c0baSSam Ravnborg 2639a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2649a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2658d5fffb9SSam Ravnborg 2661b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2671b27d05bSPekka Enberg def_bool y 2681b27d05bSPekka Enberg 269dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 27089c9c4c5SBrian Gerst def_bool y 271b32ef636Stravis@sgi.com 27208fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 27308fc4580STejun Heo def_bool y 27408fc4580STejun Heo 27508fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 27611124411STejun Heo def_bool y 27711124411STejun Heo 278801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 279801e4062SJohannes Berg def_bool y 280801e4062SJohannes Berg 281f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 282f4cb5700SJohannes Berg def_bool y 283f4cb5700SJohannes Berg 284cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 285cfe28c5dSSteve Capper def_bool y 286cfe28c5dSSteve Capper 28753313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 28853313b2cSSteve Capper def_bool y 28953313b2cSSteve Capper 2908d5fffb9SSam Ravnborgconfig ZONE_DMA32 291e0fd24a3SJan Beulich def_bool y if X86_64 2928d5fffb9SSam Ravnborg 2938d5fffb9SSam Ravnborgconfig AUDIT_ARCH 294e0fd24a3SJan Beulich def_bool y if X86_64 2958d5fffb9SSam Ravnborg 296765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 297765c68bdSIngo Molnar def_bool y 298765c68bdSIngo Molnar 2996a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3006a11f75bSAkinobu Mita def_bool y 3016a11f75bSAkinobu Mita 302d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 303d6f2d75aSAndrey Ryabinin hex 304d6f2d75aSAndrey Ryabinin depends on KASAN 3054c7c4483SKirill A. Shutemov default 0xdff8000000000000 if X86_5LEVEL 306d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 307d6f2d75aSAndrey Ryabinin 30869575d38SShane Wangconfig HAVE_INTEL_TXT 30969575d38SShane Wang def_bool y 3106ea30386SKees Cook depends on INTEL_IOMMU && ACPI 31169575d38SShane Wang 3126b0c3d44SSam Ravnborgconfig X86_32_SMP 3136b0c3d44SSam Ravnborg def_bool y 3146b0c3d44SSam Ravnborg depends on X86_32 && SMP 3156b0c3d44SSam Ravnborg 3166b0c3d44SSam Ravnborgconfig X86_64_SMP 3176b0c3d44SSam Ravnborg def_bool y 3186b0c3d44SSam Ravnborg depends on X86_64 && SMP 3196b0c3d44SSam Ravnborg 320ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 321ccbeed3aSTejun Heo def_bool y 32260a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 323ccbeed3aSTejun Heo 3242b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3252b144498SSrikar Dronamraju def_bool y 3262b144498SSrikar Dronamraju 327d20642f0SRob Herringconfig FIX_EARLYCON_MEM 328d20642f0SRob Herring def_bool y 329d20642f0SRob Herring 33098233368SKirill A. Shutemovconfig PGTABLE_LEVELS 33198233368SKirill A. Shutemov int 33277ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 33398233368SKirill A. Shutemov default 4 if X86_64 33498233368SKirill A. Shutemov default 3 if X86_PAE 33598233368SKirill A. Shutemov default 2 33698233368SKirill A. Shutemov 337506f1d07SSam Ravnborgsource "init/Kconfig" 338dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3398d5fffb9SSam Ravnborg 340506f1d07SSam Ravnborgmenu "Processor type and features" 341506f1d07SSam Ravnborg 3425ee71535SRandy Dunlapconfig ZONE_DMA 3435ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3445ee71535SRandy Dunlap default y 3455ee71535SRandy Dunlap help 3465ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3475ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3485ee71535SRandy Dunlap Disable if no such devices will be used. 3495ee71535SRandy Dunlap 3505ee71535SRandy Dunlap If unsure, say Y. 3515ee71535SRandy Dunlap 352506f1d07SSam Ravnborgconfig SMP 353506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 354506f1d07SSam Ravnborg ---help--- 355506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3564a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3574a474157SRobert Graffham than one CPU, say Y. 358506f1d07SSam Ravnborg 3594a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 360506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 361506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3624a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 363506f1d07SSam Ravnborg will run faster if you say N here. 364506f1d07SSam Ravnborg 365506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 366506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 367506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 368506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 369506f1d07SSam Ravnborg 370506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 371506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 372506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 373506f1d07SSam Ravnborg 374395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 375c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 376506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 377506f1d07SSam Ravnborg 378506f1d07SSam Ravnborg If you don't know what to do here, say N. 379506f1d07SSam Ravnborg 3809def39beSJosh Triplettconfig X86_FEATURE_NAMES 3819def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3829def39beSJosh Triplett default y 3839def39beSJosh Triplett ---help--- 3849def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3859def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3869def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3879def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3889def39beSJosh Triplett 3899def39beSJosh Triplett If in doubt, say Y. 3909def39beSJosh Triplett 3916e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3926e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3936e1315feSBorislav Petkov default y 3946e1315feSBorislav Petkov ---help--- 3956e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 3966e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 3976e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 3986e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 3996e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 4006e1315feSBorislav Petkov slower code. 4016e1315feSBorislav Petkov 40206cd9a7dSYinghai Luconfig X86_X2APIC 40306cd9a7dSYinghai Lu bool "Support x2apic" 40419e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 40506cd9a7dSYinghai Lu ---help--- 40606cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40706cd9a7dSYinghai Lu 40806cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 40906cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 41006cd9a7dSYinghai Lu 41106cd9a7dSYinghai Lu If you don't know what to do here, say N. 41206cd9a7dSYinghai Lu 4136695c85bSYinghai Luconfig X86_MPPARSE 4146e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4157a527688SJan Beulich default y 4165ab74722SIngo Molnar depends on X86_LOCAL_APIC 4178f9ca475SIngo Molnar ---help--- 4186695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4196695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4206695c85bSYinghai Lu 42126f7ef14SYinghai Luconfig X86_BIGSMP 42226f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 42326f7ef14SYinghai Lu depends on X86_32 && SMP 4248f9ca475SIngo Molnar ---help--- 42526f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 426506f1d07SSam Ravnborg 427ddd70cf9SJun Nakajimaconfig GOLDFISH 428ddd70cf9SJun Nakajima def_bool y 429ddd70cf9SJun Nakajima depends on X86_GOLDFISH 430ddd70cf9SJun Nakajima 431f01d7d51SVikas Shivappaconfig INTEL_RDT 432f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 43378e99b4aSFenghua Yu default n 43478e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 43559fe5a77SThomas Gleixner select KERNFS 43678e99b4aSFenghua Yu help 437f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 438f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 439f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 440f01d7d51SVikas Shivappa Architecture Software Developer Manual. 44178e99b4aSFenghua Yu 44278e99b4aSFenghua Yu Say N if unsure. 44378e99b4aSFenghua Yu 4448425091fSRavikiran G Thirumalaiif X86_32 445c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 446c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 447c5c606d9SRavikiran G Thirumalai default y 4488f9ca475SIngo Molnar ---help--- 44906ac8346SIngo Molnar If you disable this option then the kernel will only support 45006ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 45106ac8346SIngo Molnar systems out there.) 45206ac8346SIngo Molnar 4538425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4548425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 455cb7b8023SBen Hutchings Goldfish (Android emulator) 4568425091fSRavikiran G Thirumalai AMD Elan 4578425091fSRavikiran G Thirumalai RDC R-321x SoC 4588425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 45983125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4603f4110a4SThomas Gleixner Moorestown MID devices 46106ac8346SIngo Molnar 46206ac8346SIngo Molnar If you have one of these systems, or if you want to build a 46306ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4648425091fSRavikiran G Thirumalaiendif 46506ac8346SIngo Molnar 4668425091fSRavikiran G Thirumalaiif X86_64 4678425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4688425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4698425091fSRavikiran G Thirumalai default y 4708425091fSRavikiran G Thirumalai ---help--- 4718425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4728425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4738425091fSRavikiran G Thirumalai systems out there.) 4748425091fSRavikiran G Thirumalai 4758425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4768425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 47744b111b5SSteffen Persvold Numascale NumaChip 4788425091fSRavikiran G Thirumalai ScaleMP vSMP 4798425091fSRavikiran G Thirumalai SGI Ultraviolet 4808425091fSRavikiran G Thirumalai 4818425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4828425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4838425091fSRavikiran G Thirumalaiendif 484c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 485c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 48644b111b5SSteffen Persvoldconfig X86_NUMACHIP 48744b111b5SSteffen Persvold bool "Numascale NumaChip" 48844b111b5SSteffen Persvold depends on X86_64 48944b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 49044b111b5SSteffen Persvold depends on NUMA 49144b111b5SSteffen Persvold depends on SMP 49244b111b5SSteffen Persvold depends on X86_X2APIC 493f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 49444b111b5SSteffen Persvold ---help--- 49544b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 49644b111b5SSteffen Persvold enable more than ~168 cores. 49744b111b5SSteffen Persvold If you don't have one of these, you should say N here. 49803b48632SNick Piggin 4996a48565eSIngo Molnarconfig X86_VSMP 500c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5016276a074SBorislav Petkov select HYPERVISOR_GUEST 5026a48565eSIngo Molnar select PARAVIRT 5036a48565eSIngo Molnar depends on X86_64 && PCI 504c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 505ead91d4bSShai Fultheim depends on SMP 5068f9ca475SIngo Molnar ---help--- 5076a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5086a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5096a48565eSIngo Molnar if you have one of these machines. 5106a48565eSIngo Molnar 511c5c606d9SRavikiran G Thirumalaiconfig X86_UV 512c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 513c5c606d9SRavikiran G Thirumalai depends on X86_64 514c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 51554c28d29SJack Steiner depends on NUMA 5161ecb4ae5SAndrew Morton depends on EFI 5179d6c26e7SSuresh Siddha depends on X86_X2APIC 5181222e564SIngo Molnar depends on PCI 519c5c606d9SRavikiran G Thirumalai ---help--- 520c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 521c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 522c5c606d9SRavikiran G Thirumalai 523c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 524c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 525506f1d07SSam Ravnborg 526ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 527ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 528cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 529ddd70cf9SJun Nakajima ---help--- 530ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 531ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 532ddd70cf9SJun Nakajima Goldfish emulator say N here. 533ddd70cf9SJun Nakajima 534c751e17bSThomas Gleixnerconfig X86_INTEL_CE 535c751e17bSThomas Gleixner bool "CE4100 TV platform" 536c751e17bSThomas Gleixner depends on PCI 537c751e17bSThomas Gleixner depends on PCI_GODIRECT 5386084a6e2SJiang Liu depends on X86_IO_APIC 539c751e17bSThomas Gleixner depends on X86_32 540c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 54137bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 542da6b737bSSebastian Andrzej Siewior select OF 543da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 544c751e17bSThomas Gleixner ---help--- 545c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 546c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 547c751e17bSThomas Gleixner boxes and media devices. 548c751e17bSThomas Gleixner 5494cb9b00fSDavid Cohenconfig X86_INTEL_MID 55043605ef1SAlan Cox bool "Intel MID platform support" 55143605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 552edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5531ea7c673SAlan Cox depends on PCI 5543fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5551ea7c673SAlan Cox depends on X86_IO_APIC 5567c9c3a1eSAlan Cox select SFI 5574cb9b00fSDavid Cohen select I2C 5587c9c3a1eSAlan Cox select DW_APB_TIMER 5591ea7c673SAlan Cox select APB_TIMER 5601ea7c673SAlan Cox select INTEL_SCU_IPC 56115a713dfSMika Westerberg select MFD_INTEL_MSIC 5621ea7c673SAlan Cox ---help--- 5634cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5644cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5654cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5661ea7c673SAlan Cox 5674cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5684cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 56943605ef1SAlan Cox 5708bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5718bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5728bbc2a13SBryan O'Donoghue depends on X86_32 5738bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5748bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5758bbc2a13SBryan O'Donoghue depends on X86_TSC 5768bbc2a13SBryan O'Donoghue depends on PCI 5778bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5788bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5798bbc2a13SBryan O'Donoghue select IOSF_MBI 5808bbc2a13SBryan O'Donoghue select INTEL_IMR 5819ab6eb51SAndy Shevchenko select COMMON_CLK 5828bbc2a13SBryan O'Donoghue ---help--- 5838bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5848bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5858bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5868bbc2a13SBryan O'Donoghue 5873d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5883d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 589eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5903d48aab1SMika Westerberg select COMMON_CLK 5910f531431SMathias Nyman select PINCTRL 592eebb3e8dSAndy Shevchenko select IOSF_MBI 5933d48aab1SMika Westerberg ---help--- 5943d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 5953d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 5960f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 5970f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 5983d48aab1SMika Westerberg 59992082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 60092082a88SKen Xue bool "AMD ACPI2Platform devices support" 60192082a88SKen Xue depends on ACPI 60292082a88SKen Xue select COMMON_CLK 60392082a88SKen Xue select PINCTRL 60492082a88SKen Xue ---help--- 60592082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 60692082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 60792082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 60892082a88SKen Xue implemented under PINCTRL subsystem. 60992082a88SKen Xue 610ced3ce76SDavid E. Boxconfig IOSF_MBI 611ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 612ced3ce76SDavid E. Box depends on PCI 613ced3ce76SDavid E. Box ---help--- 614ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 615ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 616ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 617ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 618ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 619ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 620ced3ce76SDavid E. Box This list is not meant to be exclusive. 621ced3ce76SDavid E. Box - BayTrail 622ced3ce76SDavid E. Box - Braswell 623ced3ce76SDavid E. Box - Quark 624ced3ce76SDavid E. Box 625ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 626ced3ce76SDavid E. Box 627ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 628ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 629ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 630ed2226bdSDavid E. Box ---help--- 631ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 632ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 633ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 634ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 635ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 636ed2226bdSDavid E. Box device they want to access. 637ed2226bdSDavid E. Box 638ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 639ed2226bdSDavid E. Box 640c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 641c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 642506f1d07SSam Ravnborg depends on X86_32 643c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 644c5c606d9SRavikiran G Thirumalai select M486 645c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 646c5c606d9SRavikiran G Thirumalai ---help--- 647c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 648c5c606d9SRavikiran G Thirumalai as R-8610-(G). 649c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 650c5c606d9SRavikiran G Thirumalai 651e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6529c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6539c398017SIngo Molnar depends on X86_32 && SMP 654c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6558f9ca475SIngo Molnar ---help--- 656b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 657b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 658b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 659b5660ba7SH. Peter Anvin one and will fallback to default. 660d49c4288SYinghai Lu 661c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 662d49c4288SYinghai Lu 663d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6646fc108a0SJan Beulich def_bool y 665d949f36fSLinus Torvalds # MCE code calls memory_failure(): 666d949f36fSLinus Torvalds depends on X86_MCE 667d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 668d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 669d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 670d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 671d949f36fSLinus Torvalds 67283125a3aSAlessandro Rubiniconfig STA2X11 67383125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 67483125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 67583125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 67683125a3aSAlessandro Rubini select X86_DMA_REMAP 67783125a3aSAlessandro Rubini select SWIOTLB 67883125a3aSAlessandro Rubini select MFD_STA2X11 6790145071bSLinus Walleij select GPIOLIB 68083125a3aSAlessandro Rubini default n 68183125a3aSAlessandro Rubini ---help--- 68283125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 68383125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 68483125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 68583125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 68683125a3aSAlessandro Rubini standard PC machines. 68783125a3aSAlessandro Rubini 68882148d1dSShérabconfig X86_32_IRIS 68982148d1dSShérab tristate "Eurobraille/Iris poweroff module" 69082148d1dSShérab depends on X86_32 69182148d1dSShérab ---help--- 69282148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 69382148d1dSShérab to shut themselves down properly. A special I/O sequence is 69482148d1dSShérab needed to do so, which is what this module does at 69582148d1dSShérab kernel shutdown. 69682148d1dSShérab 69782148d1dSShérab This is only for Iris machines from EuroBraille. 69882148d1dSShérab 69982148d1dSShérab If unused, say N. 70082148d1dSShérab 701ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7023c2362e6SHarvey Harrison def_bool y 7033c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 704a87d0914SKen Chen depends on X86 7058f9ca475SIngo Molnar ---help--- 706506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 707506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 708506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 709506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 710506f1d07SSam Ravnborg 711506f1d07SSam Ravnborg If in doubt, say "Y". 712506f1d07SSam Ravnborg 7136276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7146276a074SBorislav Petkov bool "Linux guest support" 7158f9ca475SIngo Molnar ---help--- 7166276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7176276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7186276a074SBorislav Petkov setup. 719506f1d07SSam Ravnborg 7206276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7216276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 722506f1d07SSam Ravnborg 7236276a074SBorislav Petkovif HYPERVISOR_GUEST 724506f1d07SSam Ravnborg 725e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 726e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7278f9ca475SIngo Molnar ---help--- 728e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 729e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 730e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 731e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 732e61bd94aSEduardo Pereira Habkost 7336276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7346276a074SBorislav Petkov bool "paravirt-ops debugging" 7356276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7366276a074SBorislav Petkov ---help--- 7376276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7386276a074SBorislav Petkov a paravirt_op is missing when it is called. 7396276a074SBorislav Petkov 740b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 741b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7426ea30386SKees Cook depends on PARAVIRT && SMP 743b4ecc126SJeremy Fitzhardinge ---help--- 744b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 745b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 746b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 747b4ecc126SJeremy Fitzhardinge 7484c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7494c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 750b4ecc126SJeremy Fitzhardinge 7514c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 752b4ecc126SJeremy Fitzhardinge 75345e898b7SWaiman Longconfig QUEUED_LOCK_STAT 75445e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 755cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 75645e898b7SWaiman Long ---help--- 75745e898b7SWaiman Long Enable the collection of statistical data on the slowpath 75845e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 75945e898b7SWaiman Long them on debugfs. 76045e898b7SWaiman Long 7616276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7626276a074SBorislav Petkov 7636276a074SBorislav Petkovconfig KVM_GUEST 7646276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7656276a074SBorislav Petkov depends on PARAVIRT 7666276a074SBorislav Petkov select PARAVIRT_CLOCK 7676276a074SBorislav Petkov default y 7686276a074SBorislav Petkov ---help--- 7696276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7706276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7716276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7726276a074SBorislav Petkov underlying device model, the host provides the guest with 7736276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7746276a074SBorislav Petkov 7751e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7761e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7771e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7781e20eb85SSrivatsa Vaddagiri default n 7791e20eb85SSrivatsa Vaddagiri ---help--- 7801e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7811e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7821e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7831e20eb85SSrivatsa Vaddagiri 7846276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7856276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7866276a074SBorislav Petkov depends on PARAVIRT 7876276a074SBorislav Petkov default n 7886276a074SBorislav Petkov ---help--- 7896276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7906276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7916276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 7926276a074SBorislav Petkov that, there can be a small performance impact. 7936276a074SBorislav Petkov 7946276a074SBorislav Petkov If in doubt, say N here. 7956276a074SBorislav Petkov 7967af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 7977af192c9SGerd Hoffmann bool 7987af192c9SGerd Hoffmann 7996276a074SBorislav Petkovendif #HYPERVISOR_GUEST 80097349135SJeremy Fitzhardinge 80108677214SYinghai Luconfig NO_BOOTMEM 802774ea0bcSYinghai Lu def_bool y 80308677214SYinghai Lu 804506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 805506f1d07SSam Ravnborg 806506f1d07SSam Ravnborgconfig HPET_TIMER 8073c2362e6SHarvey Harrison def_bool X86_64 808506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8098f9ca475SIngo Molnar ---help--- 810506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 811506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 812506f1d07SSam Ravnborg present. 813506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 814506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 815506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8164e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8174e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 818506f1d07SSam Ravnborg 819506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 820506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 821506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 822506f1d07SSam Ravnborg 823506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 824506f1d07SSam Ravnborg 825506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8263c2362e6SHarvey Harrison def_bool y 8279d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 828506f1d07SSam Ravnborg 829bb24c471SJacob Panconfig APB_TIMER 830933b9463SAlan Cox def_bool y if X86_INTEL_MID 831933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 83206c3df49SJamie Iles select DW_APB_TIMER 833a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 834bb24c471SJacob Pan help 835bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 836bb24c471SJacob Pan The APBT provides a stable time base on SMP 837bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 838bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 839bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 840bb24c471SJacob Pan 8416a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 842506f1d07SSam Ravnborg# The code disables itself when not needed. 8437ae9392cSThomas Petazzoniconfig DMI 8447ae9392cSThomas Petazzoni default y 845cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8466a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8478f9ca475SIngo Molnar ---help--- 8487ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8497ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8507ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8517ae9392cSThomas Petazzoni BIOS code. 8527ae9392cSThomas Petazzoni 853506f1d07SSam Ravnborgconfig GART_IOMMU 85438901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 855506f1d07SSam Ravnborg select SWIOTLB 85623ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8578f9ca475SIngo Molnar ---help--- 858ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 859ced3c42cSIngo Molnar GART based hardware IOMMUs. 860ced3c42cSIngo Molnar 861ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 862ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 863ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 864ced3c42cSIngo Molnar 865ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 866ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 867ced3c42cSIngo Molnar 868ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 869ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 870ced3c42cSIngo Molnar 32-bit limited device. 871ced3c42cSIngo Molnar 872ced3c42cSIngo Molnar If unsure, say Y. 873506f1d07SSam Ravnborg 874506f1d07SSam Ravnborgconfig CALGARY_IOMMU 875506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 876506f1d07SSam Ravnborg select SWIOTLB 8776ea30386SKees Cook depends on X86_64 && PCI 8788f9ca475SIngo Molnar ---help--- 879506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 880506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 881506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 882506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 883506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 884506f1d07SSam Ravnborg prevents them from going anywhere except their intended 885506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 886506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 887506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 888506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 889506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 890506f1d07SSam Ravnborg If unsure, say Y. 891506f1d07SSam Ravnborg 892506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 8933c2362e6SHarvey Harrison def_bool y 8943c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 895506f1d07SSam Ravnborg depends on CALGARY_IOMMU 8968f9ca475SIngo Molnar ---help--- 897506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 898506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 899506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 900506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 901506f1d07SSam Ravnborg If unsure, say Y. 902506f1d07SSam Ravnborg 903506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 904506f1d07SSam Ravnborgconfig SWIOTLB 905a1afd01cSJoerg Roedel def_bool y if X86_64 9068f9ca475SIngo Molnar ---help--- 907506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9084454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9094454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9104454d327SJoe Millenbach with more than 3 GB of memory. 9114454d327SJoe Millenbach If unsure, say Y. 912506f1d07SSam Ravnborg 913a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9143120e25eSJan Beulich def_bool y 9153120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 916d25e26b6SLinus Torvalds 9171184dc2fSMike Travisconfig MAXSMP 918ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9196ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 92036f5101aSMike Travis select CPUMASK_OFFSTACK 9218f9ca475SIngo Molnar ---help--- 922ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9231184dc2fSMike Travis If unsure, say N. 924506f1d07SSam Ravnborg 925506f1d07SSam Ravnborgconfig NR_CPUS 92636f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 9272a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 928bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 929b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 93078637a97SMike Travis default "1" if !SMP 931b53b5edaSJosh Boyer default "8192" if MAXSMP 932b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 933c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 934c5c19941SKirill A. Shutemov default "64" if SMP 9358f9ca475SIngo Molnar ---help--- 936506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 937bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 938cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 939506f1d07SSam Ravnborg minimum value which makes sense is 2. 940506f1d07SSam Ravnborg 941506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 942506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 943506f1d07SSam Ravnborg 944506f1d07SSam Ravnborgconfig SCHED_SMT 945506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 946c8e56d20SBorislav Petkov depends on SMP 9478f9ca475SIngo Molnar ---help--- 948506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 949506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 950506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 951506f1d07SSam Ravnborg N here. 952506f1d07SSam Ravnborg 953506f1d07SSam Ravnborgconfig SCHED_MC 9543c2362e6SHarvey Harrison def_bool y 9553c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 956c8e56d20SBorislav Petkov depends on SMP 9578f9ca475SIngo Molnar ---help--- 958506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 959506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 960506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 961506f1d07SSam Ravnborg 962de966cf4STim Chenconfig SCHED_MC_PRIO 963de966cf4STim Chen bool "CPU core priorities scheduler support" 9640a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 9650a21fc12SIngo Molnar select X86_INTEL_PSTATE 9660a21fc12SIngo Molnar select CPU_FREQ 967de966cf4STim Chen default y 9685e76b2abSTim Chen ---help--- 969de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 970de966cf4STim Chen core ordering determined at manufacturing time, which allows 971de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 972de966cf4STim Chen single threaded workloads) than others. 973de966cf4STim Chen 974de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 975de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 976de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 977de966cf4STim Chen overall system performance can be achieved. 978de966cf4STim Chen 979de966cf4STim Chen This feature will have no effect on CPUs without this feature. 980de966cf4STim Chen 981de966cf4STim Chen If unsure say Y here. 9825e76b2abSTim Chen 983506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 984506f1d07SSam Ravnborg 98530b8b006SThomas Gleixnerconfig UP_LATE_INIT 98630b8b006SThomas Gleixner def_bool y 987ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 98830b8b006SThomas Gleixner 989506f1d07SSam Ravnborgconfig X86_UP_APIC 99050849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 99150849eefSJan Beulich default PCI_MSI 99238a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 9938f9ca475SIngo Molnar ---help--- 994506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 995506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 996506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 997506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 998506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 999506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1000506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1001506f1d07SSam Ravnborg lockups. 1002506f1d07SSam Ravnborg 1003506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1004506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1005506f1d07SSam Ravnborg depends on X86_UP_APIC 10068f9ca475SIngo Molnar ---help--- 1007506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1008506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1009506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1010506f1d07SSam Ravnborg 1011506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1012506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1013506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1014506f1d07SSam Ravnborg 1015506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10163c2362e6SHarvey Harrison def_bool y 10170dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1018b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 101952f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1020506f1d07SSam Ravnborg 1021506f1d07SSam Ravnborgconfig X86_IO_APIC 1022b1da1e71SJan Beulich def_bool y 1023b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1024506f1d07SSam Ravnborg 102541b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 102641b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 102741b9eb26SStefan Assmann depends on X86_IO_APIC 10288f9ca475SIngo Molnar ---help--- 102941b9eb26SStefan Assmann This option enables a workaround that fixes a source of 103041b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 103141b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 103241b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 103341b9eb26SStefan Assmann 103441b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 103541b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 103641b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 103741b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 103841b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 103941b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 104041b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 104141b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 104241b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 104341b9eb26SStefan Assmann down (vital) interrupt lines. 104441b9eb26SStefan Assmann 104541b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 104641b9eb26SStefan Assmann increased on these systems. 104741b9eb26SStefan Assmann 1048506f1d07SSam Ravnborgconfig X86_MCE 1049bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1050648ed940SChen, Gong select GENERIC_ALLOCATOR 1051e57dbaf7SBorislav Petkov default y 1052506f1d07SSam Ravnborg ---help--- 1053bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1054bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1055506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1056bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10574efc0670SAndi Kleen 10585de97c9fSTony Luckconfig X86_MCELOG_LEGACY 10595de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 10605de97c9fSTony Luck depends on X86_MCE 10615de97c9fSTony Luck ---help--- 10625de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 10635de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 10645de97c9fSTony Luck rasdaemon solution. 10655de97c9fSTony Luck 1066506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10673c2362e6SHarvey Harrison def_bool y 10683c2362e6SHarvey Harrison prompt "Intel MCE features" 1069c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10708f9ca475SIngo Molnar ---help--- 1071506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1072506f1d07SSam Ravnborg the thermal monitor. 1073506f1d07SSam Ravnborg 1074506f1d07SSam Ravnborgconfig X86_MCE_AMD 10753c2362e6SHarvey Harrison def_bool y 10763c2362e6SHarvey Harrison prompt "AMD MCE features" 1077f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 10788f9ca475SIngo Molnar ---help--- 1079506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1080506f1d07SSam Ravnborg the DRAM Error Threshold. 1081506f1d07SSam Ravnborg 10824efc0670SAndi Kleenconfig X86_ANCIENT_MCE 10836fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1084c31d9633SAndi Kleen depends on X86_32 && X86_MCE 10854efc0670SAndi Kleen ---help--- 10864efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 10875065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 10884efc0670SAndi Kleen line. 10894efc0670SAndi Kleen 1090b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1091b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 10926fc108a0SJan Beulich def_bool y 1093b2762686SAndi Kleen 1094ea149b36SAndi Kleenconfig X86_MCE_INJECT 1095bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1096ea149b36SAndi Kleen tristate "Machine check injector support" 1097ea149b36SAndi Kleen ---help--- 1098ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1099ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1100ea149b36SAndi Kleen QA it is safe to say n. 1101ea149b36SAndi Kleen 11024efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11034efc0670SAndi Kleen def_bool y 11045bb38adcSAndi Kleen depends on X86_MCE_INTEL 11054efc0670SAndi Kleen 110607dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1107e633c65aSKan Liang 11085aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11091e642812SIngo Molnar bool "Legacy VM86 support" 11105aef51c3SAndy Lutomirski default n 1111506f1d07SSam Ravnborg depends on X86_32 11128f9ca475SIngo Molnar ---help--- 11135aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11145aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11155aef51c3SAndy Lutomirski 11165aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11175aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11185aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11195aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11205aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11211e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11221e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11231e642812SIngo Molnar mode might be faster than emulation and you might want to 11241e642812SIngo Molnar enable this option. 11255aef51c3SAndy Lutomirski 11261e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11271e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11281e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11291e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11305aef51c3SAndy Lutomirski 11311e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11321e642812SIngo Molnar and slows down exception handling a tiny bit. 11335aef51c3SAndy Lutomirski 11341e642812SIngo Molnar If unsure, say N here. 11355aef51c3SAndy Lutomirski 11365aef51c3SAndy Lutomirskiconfig VM86 11375aef51c3SAndy Lutomirski bool 11385aef51c3SAndy Lutomirski default X86_LEGACY_VM86 113934273f41SH. Peter Anvin 114034273f41SH. Peter Anvinconfig X86_16BIT 114134273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 114234273f41SH. Peter Anvin default y 1143a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 114434273f41SH. Peter Anvin ---help--- 114534273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 114634273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 114734273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 114834273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 114934273f41SH. Peter Anvin 115034273f41SH. Peter Anvinconfig X86_ESPFIX32 115134273f41SH. Peter Anvin def_bool y 115234273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1153506f1d07SSam Ravnborg 1154197725deSH. Peter Anvinconfig X86_ESPFIX64 1155197725deSH. Peter Anvin def_bool y 115634273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1157506f1d07SSam Ravnborg 11581ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 11591ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 11601ad83c85SAndy Lutomirski default y 11611ad83c85SAndy Lutomirski depends on X86_64 11621ad83c85SAndy Lutomirski ---help--- 11631ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 11641ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 11651ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11661ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11671ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11681ad83c85SAndy Lutomirski 0xffffffffff600?00. 11691ad83c85SAndy Lutomirski 11701ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 11711ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 11721ad83c85SAndy Lutomirski 11731ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 11741ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 11751ad83c85SAndy Lutomirski 1176506f1d07SSam Ravnborgconfig TOSHIBA 1177506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1178506f1d07SSam Ravnborg depends on X86_32 1179506f1d07SSam Ravnborg ---help--- 1180506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1181506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1182506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1183506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1184506f1d07SSam Ravnborg 1185506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1186506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1187506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1188506f1d07SSam Ravnborg 1189506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1190506f1d07SSam Ravnborg Say N otherwise. 1191506f1d07SSam Ravnborg 1192506f1d07SSam Ravnborgconfig I8K 1193039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1194949a9d70SJean Delvare select HWMON 1195039ae585SPali Rohár select SENSORS_DELL_SMM 1196506f1d07SSam Ravnborg ---help--- 1197039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1198039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1199039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1200039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1201039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1202039ae585SPali Rohár needed userspace package i8kutils. 1203506f1d07SSam Ravnborg 1204039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1205039ae585SPali Rohár use userspace package i8kutils. 1206506f1d07SSam Ravnborg Say N otherwise. 1207506f1d07SSam Ravnborg 1208506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12099ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12109ba16087SJan Beulich depends on X86_32 1211506f1d07SSam Ravnborg ---help--- 1212506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1213506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1214506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1215506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1216506f1d07SSam Ravnborg system. 1217506f1d07SSam Ravnborg 1218506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12195e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1220506f1d07SSam Ravnborg 1221506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1222506f1d07SSam Ravnborg enable this option even if you don't need it. 1223506f1d07SSam Ravnborg Say N otherwise. 1224506f1d07SSam Ravnborg 1225506f1d07SSam Ravnborgconfig MICROCODE 12269a2bc335SBorislav Petkov bool "CPU microcode loading support" 12279a2bc335SBorislav Petkov default y 122880030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1229506f1d07SSam Ravnborg select FW_LOADER 1230506f1d07SSam Ravnborg ---help--- 1231506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12325f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12335f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12345f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12355f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12365f9c01aaSBorislav Petkov the Linux kernel. 1237506f1d07SSam Ravnborg 12385f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12395f9c01aaSBorislav Petkov in Documentation/x86/early-microcode.txt. For that you need to enable 12405f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12415f9c01aaSBorislav Petkov initrd for microcode blobs. 1242506f1d07SSam Ravnborg 12435f9c01aaSBorislav Petkov In addition, you can build-in the microcode into the kernel. For that you 12445f9c01aaSBorislav Petkov need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 12455f9c01aaSBorislav Petkov to the CONFIG_EXTRA_FIRMWARE config option. 1246506f1d07SSam Ravnborg 12478d86f390SPeter Orubaconfig MICROCODE_INTEL 1248e43f6e67SBorislav Petkov bool "Intel microcode loading support" 12498d86f390SPeter Oruba depends on MICROCODE 12508d86f390SPeter Oruba default MICROCODE 12518d86f390SPeter Oruba select FW_LOADER 12528f9ca475SIngo Molnar ---help--- 12538d86f390SPeter Oruba This options enables microcode patch loading support for Intel 12548d86f390SPeter Oruba processors. 12558d86f390SPeter Oruba 1256b8989db9SAlan For the current Intel microcode data package go to 1257b8989db9SAlan <https://downloadcenter.intel.com> and search for 1258b8989db9SAlan 'Linux Processor Microcode Data File'. 12598d86f390SPeter Oruba 126080cc9f10SPeter Orubaconfig MICROCODE_AMD 1261e43f6e67SBorislav Petkov bool "AMD microcode loading support" 126280cc9f10SPeter Oruba depends on MICROCODE 126380cc9f10SPeter Oruba select FW_LOADER 12648f9ca475SIngo Molnar ---help--- 126580cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 126680cc9f10SPeter Oruba processors will be enabled. 126780cc9f10SPeter Oruba 1268506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12693c2362e6SHarvey Harrison def_bool y 1270506f1d07SSam Ravnborg depends on MICROCODE 1271506f1d07SSam Ravnborg 1272506f1d07SSam Ravnborgconfig X86_MSR 1273506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 12748f9ca475SIngo Molnar ---help--- 1275506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1276506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1277506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1278506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1279506f1d07SSam Ravnborg systems. 1280506f1d07SSam Ravnborg 1281506f1d07SSam Ravnborgconfig X86_CPUID 1282506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 12838f9ca475SIngo Molnar ---help--- 1284506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1285506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1286506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1287506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1288506f1d07SSam Ravnborg 1289506f1d07SSam Ravnborgchoice 1290506f1d07SSam Ravnborg prompt "High Memory Support" 12916fc108a0SJan Beulich default HIGHMEM4G 1292506f1d07SSam Ravnborg depends on X86_32 1293506f1d07SSam Ravnborg 1294506f1d07SSam Ravnborgconfig NOHIGHMEM 1295506f1d07SSam Ravnborg bool "off" 1296506f1d07SSam Ravnborg ---help--- 1297506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1298506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1299506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1300506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1301506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1302506f1d07SSam Ravnborg "high memory". 1303506f1d07SSam Ravnborg 1304506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1305506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1306506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1307506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1308506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1309506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1310506f1d07SSam Ravnborg possible. 1311506f1d07SSam Ravnborg 1312506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1313506f1d07SSam Ravnborg answer "4GB" here. 1314506f1d07SSam Ravnborg 1315506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1316506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1317506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1318506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1319506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1320506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1321506f1d07SSam Ravnborg 1322506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1323506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1324506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1325506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1326506f1d07SSam Ravnborg kernel at boot time.) 1327506f1d07SSam Ravnborg 1328506f1d07SSam Ravnborg If unsure, say "off". 1329506f1d07SSam Ravnborg 1330506f1d07SSam Ravnborgconfig HIGHMEM4G 1331506f1d07SSam Ravnborg bool "4GB" 13328f9ca475SIngo Molnar ---help--- 1333506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1334506f1d07SSam Ravnborg gigabytes of physical RAM. 1335506f1d07SSam Ravnborg 1336506f1d07SSam Ravnborgconfig HIGHMEM64G 1337506f1d07SSam Ravnborg bool "64GB" 1338eb068e78SH. Peter Anvin depends on !M486 1339506f1d07SSam Ravnborg select X86_PAE 13408f9ca475SIngo Molnar ---help--- 1341506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1342506f1d07SSam Ravnborg gigabytes of physical RAM. 1343506f1d07SSam Ravnborg 1344506f1d07SSam Ravnborgendchoice 1345506f1d07SSam Ravnborg 1346506f1d07SSam Ravnborgchoice 13476a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1348506f1d07SSam Ravnborg default VMSPLIT_3G 1349506f1d07SSam Ravnborg depends on X86_32 13508f9ca475SIngo Molnar ---help--- 1351506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1352506f1d07SSam Ravnborg 1353506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1354506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1355506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1356506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1357506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1358506f1d07SSam Ravnborg available to user programs, making the address space there 1359506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1360506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1361506f1d07SSam Ravnborg kernel modules. 1362506f1d07SSam Ravnborg 1363506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1364506f1d07SSam Ravnborg option alone! 1365506f1d07SSam Ravnborg 1366506f1d07SSam Ravnborg config VMSPLIT_3G 1367506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1368506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1369506f1d07SSam Ravnborg depends on !X86_PAE 1370506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1371506f1d07SSam Ravnborg config VMSPLIT_2G 1372506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1373506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1374506f1d07SSam Ravnborg depends on !X86_PAE 1375506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1376506f1d07SSam Ravnborg config VMSPLIT_1G 1377506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1378506f1d07SSam Ravnborgendchoice 1379506f1d07SSam Ravnborg 1380506f1d07SSam Ravnborgconfig PAGE_OFFSET 1381506f1d07SSam Ravnborg hex 1382506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1383506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1384506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1385506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1386506f1d07SSam Ravnborg default 0xC0000000 1387506f1d07SSam Ravnborg depends on X86_32 1388506f1d07SSam Ravnborg 1389506f1d07SSam Ravnborgconfig HIGHMEM 13903c2362e6SHarvey Harrison def_bool y 1391506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1392506f1d07SSam Ravnborg 1393506f1d07SSam Ravnborgconfig X86_PAE 13949ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1395506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 13969d99c712SChristian Melki select SWIOTLB 13978f9ca475SIngo Molnar ---help--- 1398506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1399506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1400506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1401506f1d07SSam Ravnborg consumes more pagetable space per process. 1402506f1d07SSam Ravnborg 140377ef56e4SKirill A. Shutemovconfig X86_5LEVEL 140477ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 140577ef56e4SKirill A. Shutemov depends on X86_64 140677ef56e4SKirill A. Shutemov ---help--- 140777ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 140877ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 140977ef56e4SKirill A. Shutemov physical address space. 141077ef56e4SKirill A. Shutemov 141177ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 141277ef56e4SKirill A. Shutemov 141377ef56e4SKirill A. Shutemov Note: a kernel with this option enabled can only be booted 141477ef56e4SKirill A. Shutemov on machines that support the feature. 141577ef56e4SKirill A. Shutemov 141677ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 141777ef56e4SKirill A. Shutemov information. 141877ef56e4SKirill A. Shutemov 141977ef56e4SKirill A. Shutemov Say N if unsure. 142077ef56e4SKirill A. Shutemov 1421600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14223120e25eSJan Beulich def_bool y 14233120e25eSJan Beulich depends on X86_64 || X86_PAE 1424600715dcSJeremy Fitzhardinge 142566f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14263120e25eSJan Beulich def_bool y 14273120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 142866f2b061SFUJITA Tomonori 142910971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1430e5008abeSLuis R. Rodriguez def_bool y 1431e5008abeSLuis R. Rodriguez depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 14328f9ca475SIngo Molnar ---help--- 143310971ab2SIngo Molnar Certain kernel features effectively disable kernel 143410971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 143510971ab2SIngo Molnar supports them), so don't confuse the user by printing 143610971ab2SIngo Molnar that we have them enabled. 14379e899816SNick Piggin 14387744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 14397744ccdbSTom Lendacky def_bool y 14407744ccdbSTom Lendacky 14417744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 14427744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 14437744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 14447744ccdbSTom Lendacky ---help--- 14457744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 14467744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 14477744ccdbSTom Lendacky Encryption (SME). 14487744ccdbSTom Lendacky 14497744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 14507744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 14517744ccdbSTom Lendacky default y 14527744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 14537744ccdbSTom Lendacky ---help--- 14547744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 14557744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 14567744ccdbSTom Lendacky 14577744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 14587744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 14597744ccdbSTom Lendacky 14607744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 14617744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 14627744ccdbSTom Lendacky 1463f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1464f88a68faSTom Lendacky def_bool y 1465f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1466f88a68faSTom Lendacky 1467506f1d07SSam Ravnborg# Common NUMA Features 1468506f1d07SSam Ravnborgconfig NUMA 1469fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1470506f1d07SSam Ravnborg depends on SMP 1471b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1472b5660ba7SH. Peter Anvin default y if X86_BIGSMP 14738f9ca475SIngo Molnar ---help--- 1474506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1475fd51b2d7SKOSAKI Motohiro 1476506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1477506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1478506f1d07SSam Ravnborg NUMA awareness to the kernel. 1479506f1d07SSam Ravnborg 1480c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1481fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1482fd51b2d7SKOSAKI Motohiro 1483b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 14847cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1485fd51b2d7SKOSAKI Motohiro 1486fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1487506f1d07SSam Ravnborg 1488eec1d4faSHans Rosenfeldconfig AMD_NUMA 14893c2362e6SHarvey Harrison def_bool y 14903c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 14915da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 14928f9ca475SIngo Molnar ---help--- 1493eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1494eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1495eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1496eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1497eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1498506f1d07SSam Ravnborg 1499506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15003c2362e6SHarvey Harrison def_bool y 15013c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1502506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1503506f1d07SSam Ravnborg select ACPI_NUMA 15048f9ca475SIngo Molnar ---help--- 1505506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1506506f1d07SSam Ravnborg 15076ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15086ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15096ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15106ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15116ec6e0d9SSuresh Siddha# for details. 15126ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15136ec6e0d9SSuresh Siddha def_bool y 15146ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15156ec6e0d9SSuresh Siddha 1516506f1d07SSam Ravnborgconfig NUMA_EMU 1517506f1d07SSam Ravnborg bool "NUMA emulation" 15181b7e03efSTejun Heo depends on NUMA 15198f9ca475SIngo Molnar ---help--- 1520506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1521506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1522506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1523506f1d07SSam Ravnborg 1524506f1d07SSam Ravnborgconfig NODES_SHIFT 1525d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 152651591e31SDavid Rientjes range 1 10 152751591e31SDavid Rientjes default "10" if MAXSMP 1528506f1d07SSam Ravnborg default "6" if X86_64 1529506f1d07SSam Ravnborg default "3" 1530506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15318f9ca475SIngo Molnar ---help--- 15321184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1533692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1534506f1d07SSam Ravnborg 1535506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15363c2362e6SHarvey Harrison def_bool y 1537506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1538506f1d07SSam Ravnborg 1539506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 15403c2362e6SHarvey Harrison def_bool y 1541506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1542506f1d07SSam Ravnborg 1543506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1544506f1d07SSam Ravnborg def_bool y 15453b16651fSTejun Heo depends on X86_32 && !NUMA 1546506f1d07SSam Ravnborg 1547506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1548506f1d07SSam Ravnborg def_bool y 1549b263295dSChristoph Lameter depends on NUMA && X86_32 1550506f1d07SSam Ravnborg 1551506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1552506f1d07SSam Ravnborg def_bool y 1553b263295dSChristoph Lameter depends on NUMA && X86_32 1554b263295dSChristoph Lameter 1555506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1556506f1d07SSam Ravnborg def_bool y 15576ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1558506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1559506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1560506f1d07SSam Ravnborg 15613b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 15623b16651fSTejun Heo def_bool y 15633b16651fSTejun Heo depends on X86_64 15643b16651fSTejun Heo 1565506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1566506f1d07SSam Ravnborg def_bool y 1567b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1568506f1d07SSam Ravnborg 1569506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1570a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 15713120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1572a0842b70SToshi Kani help 1573a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1574a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1575a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1576506f1d07SSam Ravnborg 15773b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 15783b16651fSTejun Heo def_bool y 15793b16651fSTejun Heo depends on X86_64 && PROC_KCORE 15803b16651fSTejun Heo 1581a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1582a29815a3SAvi Kivity hex 1583a29815a3SAvi Kivity default 0 if X86_32 1584a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1585a29815a3SAvi Kivity 1586506f1d07SSam Ravnborgsource "mm/Kconfig" 1587506f1d07SSam Ravnborg 15887a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 15897a67832cSDan Williams bool 15907a67832cSDan Williams 1591ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 15927a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 15939f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 15949f53f9faSDan Williams depends on BLK_DEV 15957a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 15969f53f9faSDan Williams select LIBNVDIMM 1597ec776ef6SChristoph Hellwig help 1598ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1599ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1600ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1601ec776ef6SChristoph Hellwig they can be used for persistent storage. 1602ec776ef6SChristoph Hellwig 1603ec776ef6SChristoph Hellwig Say Y if unsure. 1604ec776ef6SChristoph Hellwig 1605506f1d07SSam Ravnborgconfig HIGHPTE 1606506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16076fc108a0SJan Beulich depends on HIGHMEM 16088f9ca475SIngo Molnar ---help--- 1609506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1610506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1611506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1612506f1d07SSam Ravnborg entries in high memory. 1613506f1d07SSam Ravnborg 16149f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16159f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16168f9ca475SIngo Molnar ---help--- 16179f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16189f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16199f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16209f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16219f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16229f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16239f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16248c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16259f077871SJeremy Fitzhardinge 16269f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16279f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16289f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16299f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16309f077871SJeremy Fitzhardinge 16319f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16329f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16339f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16349f077871SJeremy Fitzhardinge memory. 16359f077871SJeremy Fitzhardinge 1636c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1637c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1638c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1639c885df50SJeremy Fitzhardinge default y 16408f9ca475SIngo Molnar ---help--- 1641c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1642c885df50SJeremy Fitzhardinge on or off. 1643c885df50SJeremy Fitzhardinge 16449ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1645d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1646d0cd7425SH. Peter Anvin default 64 1647d0cd7425SH. Peter Anvin range 4 640 16488f9ca475SIngo Molnar ---help--- 1649d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1650fc381519SIngo Molnar 1651d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1652d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1653fc381519SIngo Molnar 1654d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1655d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1656d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1657d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1658fc381519SIngo Molnar 1659d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1660d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1661d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1662d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1663d0cd7425SH. Peter Anvin entire low memory range. 1664d0cd7425SH. Peter Anvin 1665d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1666d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1667d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1668d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1669d0cd7425SH. Peter Anvin typical corruption patterns. 1670d0cd7425SH. Peter Anvin 1671d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1672fc381519SIngo Molnar 1673506f1d07SSam Ravnborgconfig MATH_EMULATION 1674506f1d07SSam Ravnborg bool 1675a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1676506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1677506f1d07SSam Ravnborg ---help--- 1678506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1679506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1680506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1681506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1682506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1683506f1d07SSam Ravnborg coprocessor or this emulation. 1684506f1d07SSam Ravnborg 1685506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1686506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1687506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1688506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1689506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1690506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1691506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1692506f1d07SSam Ravnborg intend to use this kernel on different machines. 1693506f1d07SSam Ravnborg 1694506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1695506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1696506f1d07SSam Ravnborg 1697506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1698506f1d07SSam Ravnborg kernel, it won't hurt. 1699506f1d07SSam Ravnborg 1700506f1d07SSam Ravnborgconfig MTRR 17016fc108a0SJan Beulich def_bool y 17026a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1703506f1d07SSam Ravnborg ---help--- 1704506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1705506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1706506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1707506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1708506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1709506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1710506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1711506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1712506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1713506f1d07SSam Ravnborg 1714506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1715506f1d07SSam Ravnborg control registers on other processors can be easily supported 1716506f1d07SSam Ravnborg as well: 1717506f1d07SSam Ravnborg 1718506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1719506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1720506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1721506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1722506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1723506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1724506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1725506f1d07SSam Ravnborg 1726506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1727506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1728506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1729506f1d07SSam Ravnborg 1730506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1731506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1732506f1d07SSam Ravnborg 17337225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1734506f1d07SSam Ravnborg 173595ffa243SYinghai Luconfig MTRR_SANITIZER 17362ffb3501SYinghai Lu def_bool y 173795ffa243SYinghai Lu prompt "MTRR cleanup support" 173895ffa243SYinghai Lu depends on MTRR 17398f9ca475SIngo Molnar ---help--- 1740aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1741aba3728cSThomas Gleixner add writeback entries. 174295ffa243SYinghai Lu 1743aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1744692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1745aba3728cSThomas Gleixner mtrr_chunk_size. 174695ffa243SYinghai Lu 17472ffb3501SYinghai Lu If unsure, say Y. 174895ffa243SYinghai Lu 174995ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1750f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1751f5098d62SYinghai Lu range 0 1 1752f5098d62SYinghai Lu default "0" 175395ffa243SYinghai Lu depends on MTRR_SANITIZER 17548f9ca475SIngo Molnar ---help--- 1755f5098d62SYinghai Lu Enable mtrr cleanup default value 175695ffa243SYinghai Lu 175712031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 175812031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 175912031a62SYinghai Lu range 0 7 176012031a62SYinghai Lu default "1" 176112031a62SYinghai Lu depends on MTRR_SANITIZER 17628f9ca475SIngo Molnar ---help--- 176312031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1764aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 176512031a62SYinghai Lu 17662e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 17676fc108a0SJan Beulich def_bool y 17686a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 17692a8a2719SIngo Molnar depends on MTRR 17708f9ca475SIngo Molnar ---help--- 17712e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1772042b78e4SVenki Pallipadi 17732e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 17742e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 17752e5d9c85Svenkatesh.pallipadi@intel.com 17762e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1777042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 17782e5d9c85Svenkatesh.pallipadi@intel.com 17792e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 17802e5d9c85Svenkatesh.pallipadi@intel.com 178146cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 178246cf98cdSVenkatesh Pallipadi def_bool y 178346cf98cdSVenkatesh Pallipadi depends on X86_PAT 178446cf98cdSVenkatesh Pallipadi 1785628c6246SH. Peter Anvinconfig ARCH_RANDOM 1786628c6246SH. Peter Anvin def_bool y 1787628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1788628c6246SH. Peter Anvin ---help--- 1789628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1790628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1791628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1792628c6246SH. Peter Anvin secure hardware random number generator. 1793628c6246SH. Peter Anvin 179451ae4a2dSH. Peter Anvinconfig X86_SMAP 179551ae4a2dSH. Peter Anvin def_bool y 179651ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 179751ae4a2dSH. Peter Anvin ---help--- 179851ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 179951ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 180051ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 180151ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 180251ae4a2dSH. Peter Anvin 180351ae4a2dSH. Peter Anvin If unsure, say Y. 180451ae4a2dSH. Peter Anvin 180572e9b5feSDave Hansenconfig X86_INTEL_MPX 180672e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 180772e9b5feSDave Hansen def_bool n 1808df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1809df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1810df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 181172e9b5feSDave Hansen ---help--- 181272e9b5feSDave Hansen MPX provides hardware features that can be used in 181372e9b5feSDave Hansen conjunction with compiler-instrumented code to check 181472e9b5feSDave Hansen memory references. It is designed to detect buffer 181572e9b5feSDave Hansen overflow or underflow bugs. 181672e9b5feSDave Hansen 181772e9b5feSDave Hansen This option enables running applications which are 181872e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 181972e9b5feSDave Hansen itself inside the kernel or to protect the kernel 182072e9b5feSDave Hansen against bad memory references. 182172e9b5feSDave Hansen 182272e9b5feSDave Hansen Enabling this option will make the kernel larger: 182372e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 182472e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 182572e9b5feSDave Hansen will increase the kernel memory overhead of each 182672e9b5feSDave Hansen process and adds some branches to paths used during 182772e9b5feSDave Hansen exec() and munmap(). 182872e9b5feSDave Hansen 182972e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 183072e9b5feSDave Hansen 183172e9b5feSDave Hansen If unsure, say N. 183272e9b5feSDave Hansen 183335e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1834284244a9SDave Hansen prompt "Intel Memory Protection Keys" 183535e97790SDave Hansen def_bool y 1836284244a9SDave Hansen # Note: only available in 64-bit mode 183735e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 183852c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 183952c8e601SIngo Molnar select ARCH_HAS_PKEYS 1840284244a9SDave Hansen ---help--- 1841284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1842284244a9SDave Hansen page-based protections, but without requiring modification of the 1843284244a9SDave Hansen page tables when an application changes protection domains. 1844284244a9SDave Hansen 1845284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1846284244a9SDave Hansen 1847284244a9SDave Hansen If unsure, say y. 184835e97790SDave Hansen 1849506f1d07SSam Ravnborgconfig EFI 18509ba16087SJan Beulich bool "EFI runtime service support" 18515b83683fSHuang, Ying depends on ACPI 1852f6ce5002SSergey Vlasov select UCS2_STRING 1853022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1854506f1d07SSam Ravnborg ---help--- 18558b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1856506f1d07SSam Ravnborg available (such as the EFI variable services). 1857506f1d07SSam Ravnborg 18588b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 18598b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 18608b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 18618b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 18628b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 18638b2cb7a8SHuang, Ying platforms. 1864506f1d07SSam Ravnborg 1865291f3632SMatt Flemingconfig EFI_STUB 1866291f3632SMatt Fleming bool "EFI stub support" 1867b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 18687b2a583aSMatt Fleming select RELOCATABLE 1869291f3632SMatt Fleming ---help--- 1870291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1871291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1872291f3632SMatt Fleming 18734172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 18740c759662SMatt Fleming 18757d453eeeSMatt Flemingconfig EFI_MIXED 18767d453eeeSMatt Fleming bool "EFI mixed-mode support" 18777d453eeeSMatt Fleming depends on EFI_STUB && X86_64 18787d453eeeSMatt Fleming ---help--- 18797d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 18807d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 18817d453eeeSMatt Fleming mode. 18827d453eeeSMatt Fleming 18837d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 18847d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 18857d453eeeSMatt Fleming the EFI handover protocol must be used. 18867d453eeeSMatt Fleming 18877d453eeeSMatt Fleming If unsure, say N. 18887d453eeeSMatt Fleming 1889506f1d07SSam Ravnborgconfig SECCOMP 18903c2362e6SHarvey Harrison def_bool y 18913c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 18928f9ca475SIngo Molnar ---help--- 1893506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1894506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1895506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1896506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1897506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1898506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 18999c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1900506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1901506f1d07SSam Ravnborg defined by each seccomp mode. 1902506f1d07SSam Ravnborg 1903506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1904506f1d07SSam Ravnborg 1905506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1906506f1d07SSam Ravnborg 1907506f1d07SSam Ravnborgconfig KEXEC 1908506f1d07SSam Ravnborg bool "kexec system call" 19092965faa5SDave Young select KEXEC_CORE 19108f9ca475SIngo Molnar ---help--- 1911506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1912506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1913506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1914506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1915506f1d07SSam Ravnborg 1916506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1917506f1d07SSam Ravnborg 1918506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1919506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1920bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1921bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1922bf220695SGeert Uytterhoeven made. 1923506f1d07SSam Ravnborg 192474ca317cSVivek Goyalconfig KEXEC_FILE 192574ca317cSVivek Goyal bool "kexec file based system call" 19262965faa5SDave Young select KEXEC_CORE 192774ca317cSVivek Goyal select BUILD_BIN2C 192874ca317cSVivek Goyal depends on X86_64 192974ca317cSVivek Goyal depends on CRYPTO=y 193074ca317cSVivek Goyal depends on CRYPTO_SHA256=y 193174ca317cSVivek Goyal ---help--- 193274ca317cSVivek Goyal This is new version of kexec system call. This system call is 193374ca317cSVivek Goyal file based and takes file descriptors as system call argument 193474ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 193574ca317cSVivek Goyal accepted by previous system call. 193674ca317cSVivek Goyal 19378e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 19388e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 193974ca317cSVivek Goyal depends on KEXEC_FILE 19408e7d8381SVivek Goyal ---help--- 19418e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1942d8eb8940SBorislav Petkov the kexec_file_load() syscall. 19438e7d8381SVivek Goyal 1944d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1945d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1946d8eb8940SBorislav Petkov loaded in order for this to work. 19478e7d8381SVivek Goyal 19488e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 19498e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 19508e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 19518e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 19528e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 19538e7d8381SVivek Goyal ---help--- 19548e7d8381SVivek Goyal Enable bzImage signature verification support. 19558e7d8381SVivek Goyal 1956506f1d07SSam Ravnborgconfig CRASH_DUMP 195704b69447SPavel Machek bool "kernel crash dumps" 1958506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 19598f9ca475SIngo Molnar ---help--- 1960506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1961506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1962506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1963506f1d07SSam Ravnborg a specially reserved region and then later executed after 1964506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1965506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1966506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1967506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1968506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1969506f1d07SSam Ravnborg 19703ab83521SHuang Yingconfig KEXEC_JUMP 19716ea30386SKees Cook bool "kexec jump" 1972fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 19738f9ca475SIngo Molnar ---help--- 197489081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 197589081d17SHuang Ying code in physical address mode via KEXEC 19763ab83521SHuang Ying 1977506f1d07SSam Ravnborgconfig PHYSICAL_START 19786a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1979ceefccc9SH. Peter Anvin default "0x1000000" 19808f9ca475SIngo Molnar ---help--- 1981506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1982506f1d07SSam Ravnborg 1983506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1984506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1985506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1986506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1987506f1d07SSam Ravnborg address. 1988506f1d07SSam Ravnborg 1989506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1990506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1991506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1992506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1993506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1994506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1995506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1996506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1997506f1d07SSam Ravnborg 1998ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 1999ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2000ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2001ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2002ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2003ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2004ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2005ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2006ceefccc9SH. Peter Anvin for more details about crash dumps. 2007506f1d07SSam Ravnborg 2008506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2009506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2010506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2011506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2012506f1d07SSam Ravnborg is present because there are users out there who continue to use 2013506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2014506f1d07SSam Ravnborg line. 2015506f1d07SSam Ravnborg 2016506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2017506f1d07SSam Ravnborg 2018506f1d07SSam Ravnborgconfig RELOCATABLE 201926717808SH. Peter Anvin bool "Build a relocatable kernel" 202026717808SH. Peter Anvin default y 20218f9ca475SIngo Molnar ---help--- 2022506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2023506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2024506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2025506f1d07SSam Ravnborg but are discarded at runtime. 2026506f1d07SSam Ravnborg 2027506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2028506f1d07SSam Ravnborg must live at a different physical address than the primary 2029506f1d07SSam Ravnborg kernel. 2030506f1d07SSam Ravnborg 2031506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2032506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 20338ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2034506f1d07SSam Ravnborg 20358ab3820fSKees Cookconfig RANDOMIZE_BASE 2036e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 20378ab3820fSKees Cook depends on RELOCATABLE 20386807c846SIngo Molnar default y 20398ab3820fSKees Cook ---help--- 2040e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2041e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2042e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2043e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2044e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2045e8581e3dSBaoquan He code internals. 2046e8581e3dSBaoquan He 2047ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2048ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2049ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2050ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2051ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2052ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2053ed9f007eSKees Cook 2054ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2055ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2056ed9f007eSKees Cook 512MB (8 bits of entropy). 20578ab3820fSKees Cook 2058a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2059e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2060e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2061ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2062ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2063ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2064ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2065ed9f007eSKees Cook theoretically possible, but the implementations are further 2066ed9f007eSKees Cook limited due to memory layouts. 2067e8581e3dSBaoquan He 20686807c846SIngo Molnar If unsure, say Y. 2069da2b6fb9SKees Cook 20708ab3820fSKees Cook# Relocation on x86 needs some additional build support 2071845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2072845adf72SH. Peter Anvin def_bool y 20738ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2074845adf72SH. Peter Anvin 2075506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2076a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 20778ab3820fSKees Cook default "0x200000" 2078a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2079a0215061SKees Cook range 0x200000 0x1000000 if X86_64 20808f9ca475SIngo Molnar ---help--- 2081506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2082506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2083506f1d07SSam Ravnborg address which meets above alignment restriction. 2084506f1d07SSam Ravnborg 2085506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2086506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2087506f1d07SSam Ravnborg address aligned to above value and run from there. 2088506f1d07SSam Ravnborg 2089506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2090506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2091506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2092506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2093506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2094506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2095506f1d07SSam Ravnborg above alignment restrictions. 2096506f1d07SSam Ravnborg 2097a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2098a0215061SKees Cook this value must be a multiple of 0x200000. 2099a0215061SKees Cook 2100506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2101506f1d07SSam Ravnborg 21020483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21030483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21040483e1faSThomas Garnier depends on X86_64 21050483e1faSThomas Garnier depends on RANDOMIZE_BASE 21060483e1faSThomas Garnier default RANDOMIZE_BASE 21070483e1faSThomas Garnier ---help--- 21080483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21090483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21100483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21110483e1faSThomas Garnier 21120483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21130483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21140483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21150483e1faSThomas Garnier addresses for each memory section. 21160483e1faSThomas Garnier 21176807c846SIngo Molnar If unsure, say Y. 21180483e1faSThomas Garnier 211990397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 212090397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 212190397a41SThomas Garnier depends on RANDOMIZE_MEMORY 212290397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 212390397a41SThomas Garnier default "0x0" 212490397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 212590397a41SThomas Garnier range 0x0 0x40 212690397a41SThomas Garnier ---help--- 212790397a41SThomas Garnier Define the padding in terabytes added to the existing physical 212890397a41SThomas Garnier memory size during kernel memory randomization. It is useful 212990397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 213090397a41SThomas Garnier address randomization. 213190397a41SThomas Garnier 213290397a41SThomas Garnier If unsure, leave at the default value. 213390397a41SThomas Garnier 2134506f1d07SSam Ravnborgconfig HOTPLUG_CPU 21357c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 213640b31360SStephen Rothwell depends on SMP 2137506f1d07SSam Ravnborg ---help--- 21387c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 21397c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 21407c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 21417c13e6a3SDimitri Sivanich automatically on SMP systems. ) 21427c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2143506f1d07SSam Ravnborg 214480aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 214580aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 214680aa1dffSFenghua Yu default n 21472c922cd0SKees Cook depends on HOTPLUG_CPU 214880aa1dffSFenghua Yu ---help--- 214980aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 215080aa1dffSFenghua Yu 215180aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 215280aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 215380aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 215480aa1dffSFenghua Yu 215580aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 215680aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 215780aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 215880aa1dffSFenghua Yu 215980aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 216080aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 216180aa1dffSFenghua Yu 216280aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 216380aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 216480aa1dffSFenghua Yu be other CPU0 dependencies. 216580aa1dffSFenghua Yu 216680aa1dffSFenghua Yu Please make sure the dependencies are under your control before 216780aa1dffSFenghua Yu you enable this feature. 216880aa1dffSFenghua Yu 216980aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 217080aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 217180aa1dffSFenghua Yu parameter cpu0_hotplug. 217280aa1dffSFenghua Yu 2173a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2174a71c8bc5SFenghua Yu def_bool n 2175a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 21762c922cd0SKees Cook depends on HOTPLUG_CPU 2177a71c8bc5SFenghua Yu ---help--- 2178a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2179a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2180a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2181a71c8bc5SFenghua Yu 2182a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2183a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2184a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2185a71c8bc5SFenghua Yu 2186a71c8bc5SFenghua Yu If unsure, say N. 2187a71c8bc5SFenghua Yu 2188506f1d07SSam Ravnborgconfig COMPAT_VDSO 2189b0b49f26SAndy Lutomirski def_bool n 2190b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2191953fee1dSIngo Molnar depends on COMPAT_32 21928f9ca475SIngo Molnar ---help--- 2193b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2194b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2195b0b49f26SAndy Lutomirski indicated in its segment table. 2196e84446deSRandy Dunlap 2197b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2198b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2199b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2200b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2201b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2202506f1d07SSam Ravnborg 2203b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2204b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2205b0b49f26SAndy Lutomirski 2206b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2207b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2208b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2209b0b49f26SAndy Lutomirski 2210b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2211b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2212506f1d07SSam Ravnborg 22133dc33bd3SKees Cookchoice 22143dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22153dc33bd3SKees Cook depends on X86_64 22163dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 22173dc33bd3SKees Cook help 22183dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 22193dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 22203dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 22213dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22223dc33bd3SKees Cook 22233dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 22243dc33bd3SKees Cook line parameter vsyscall=[native|emulate|none]. 22253dc33bd3SKees Cook 22263dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22273dc33bd3SKees Cook static binaries, you can say None without a performance penalty 22283dc33bd3SKees Cook to improve security. 22293dc33bd3SKees Cook 22303dc33bd3SKees Cook If unsure, select "Emulate". 22313dc33bd3SKees Cook 22323dc33bd3SKees Cook config LEGACY_VSYSCALL_NATIVE 22333dc33bd3SKees Cook bool "Native" 22343dc33bd3SKees Cook help 22353dc33bd3SKees Cook Actual executable code is located in the fixed vsyscall 22363dc33bd3SKees Cook address mapping, implementing time() efficiently. Since 22373dc33bd3SKees Cook this makes the mapping executable, it can be used during 22383dc33bd3SKees Cook security vulnerability exploitation (traditionally as 22393dc33bd3SKees Cook ROP gadgets). This configuration is not recommended. 22403dc33bd3SKees Cook 22413dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 22423dc33bd3SKees Cook bool "Emulate" 22433dc33bd3SKees Cook help 22443dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 22453dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 22463dc33bd3SKees Cook non-executable, but it still contains known contents, 22473dc33bd3SKees Cook which could be used in certain rare security vulnerability 22483dc33bd3SKees Cook exploits. This configuration is recommended when userspace 22493dc33bd3SKees Cook still uses the vsyscall area. 22503dc33bd3SKees Cook 22513dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 22523dc33bd3SKees Cook bool "None" 22533dc33bd3SKees Cook help 22543dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 22553dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 22563dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 22573dc33bd3SKees Cook will be reported to dmesg, so that either old or 22583dc33bd3SKees Cook malicious userspace programs can be identified. 22593dc33bd3SKees Cook 22603dc33bd3SKees Cookendchoice 22613dc33bd3SKees Cook 2262516cbf37STim Birdconfig CMDLINE_BOOL 2263516cbf37STim Bird bool "Built-in kernel command line" 22648f9ca475SIngo Molnar ---help--- 2265516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2266516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2267516cbf37STim Bird necessary or convenient to provide some or all of the 2268516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2269516cbf37STim Bird to not rely on the boot loader to provide them.) 2270516cbf37STim Bird 2271516cbf37STim Bird To compile command line arguments into the kernel, 2272516cbf37STim Bird set this option to 'Y', then fill in the 227369711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2274516cbf37STim Bird 2275516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2276516cbf37STim Bird should leave this option set to 'N'. 2277516cbf37STim Bird 2278516cbf37STim Birdconfig CMDLINE 2279516cbf37STim Bird string "Built-in kernel command string" 2280516cbf37STim Bird depends on CMDLINE_BOOL 2281516cbf37STim Bird default "" 22828f9ca475SIngo Molnar ---help--- 2283516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2284516cbf37STim Bird image and used at boot time. If the boot loader provides a 2285516cbf37STim Bird command line at boot time, it is appended to this string to 2286516cbf37STim Bird form the full kernel command line, when the system boots. 2287516cbf37STim Bird 2288516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2289516cbf37STim Bird change this behavior. 2290516cbf37STim Bird 2291516cbf37STim Bird In most cases, the command line (whether built-in or provided 2292516cbf37STim Bird by the boot loader) should specify the device for the root 2293516cbf37STim Bird file system. 2294516cbf37STim Bird 2295516cbf37STim Birdconfig CMDLINE_OVERRIDE 2296516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2297516cbf37STim Bird depends on CMDLINE_BOOL 22988f9ca475SIngo Molnar ---help--- 2299516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2300516cbf37STim Bird command line, and use ONLY the built-in command line. 2301516cbf37STim Bird 2302516cbf37STim Bird This is used to work around broken boot loaders. This should 2303516cbf37STim Bird be set to 'N' under normal conditions. 2304516cbf37STim Bird 2305a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2306a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2307a5b9e5a2SAndy Lutomirski default y 2308a5b9e5a2SAndy Lutomirski ---help--- 2309a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2310a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2311a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2312a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2313a5b9e5a2SAndy Lutomirski threading libraries. 2314a5b9e5a2SAndy Lutomirski 2315a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2316a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2317a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2318a5b9e5a2SAndy Lutomirski 2319a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2320a5b9e5a2SAndy Lutomirski 2321b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2322b700e7f0SSeth Jennings 2323506f1d07SSam Ravnborgendmenu 2324506f1d07SSam Ravnborg 23253072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 23263072e413SMichal Hocko def_bool y 23273072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 23283072e413SMichal Hocko 2329506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2330506f1d07SSam Ravnborg def_bool y 2331506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2332506f1d07SSam Ravnborg 233335551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 233435551053SGary Hade def_bool y 233535551053SGary Hade depends on MEMORY_HOTPLUG 233635551053SGary Hade 2337e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2338645a7919STejun Heo def_bool y 2339e534c7c5SLee Schermerhorn depends on NUMA 2340e534c7c5SLee Schermerhorn 23419491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 23429491846fSKirill A. Shutemov def_bool y 23439491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 23449491846fSKirill A. Shutemov 2345c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2346c177c81eSNaoya Horiguchi def_bool y 2347c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2348c177c81eSNaoya Horiguchi 23499c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 23509c670ea3SNaoya Horiguchi def_bool y 23519c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 23529c670ea3SNaoya Horiguchi 2353da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2354e279b6c1SSam Ravnborg 2355e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 23563c2362e6SHarvey Harrison def_bool y 2357e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2358e279b6c1SSam Ravnborg 2359e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2360e279b6c1SSam Ravnborg 2361e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2362e279b6c1SSam Ravnborg 2363efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2364efafc8b2SFeng Tang 2365a6b68076SAndi Kleenconfig X86_APM_BOOT 23666fc108a0SJan Beulich def_bool y 2367282e5aabSPaul Bolle depends on APM 2368a6b68076SAndi Kleen 2369e279b6c1SSam Ravnborgmenuconfig APM 2370e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2371efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2372e279b6c1SSam Ravnborg ---help--- 2373e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2374e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2375e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2376e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2377e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2378e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2379e279b6c1SSam Ravnborg 2380e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2381e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2382e279b6c1SSam Ravnborg 2383e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2384e279b6c1SSam Ravnborg machines with more than one CPU. 2385e279b6c1SSam Ravnborg 2386e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 23872dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 23882dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2389e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2390e279b6c1SSam Ravnborg 2391e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2392e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2393e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2394e279b6c1SSam Ravnborg 2395e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2396e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2397e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2398e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2399e279b6c1SSam Ravnborg 2400e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2401e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2402e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2403e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2404e279b6c1SSam Ravnborg APM in your BIOS). 2405e279b6c1SSam Ravnborg 2406e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2407e279b6c1SSam Ravnborg "weird" problems: 2408e279b6c1SSam Ravnborg 2409e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2410e279b6c1SSam Ravnborg enabled. 2411e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2412e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2413e279b6c1SSam Ravnborg the "no387" option to the kernel 2414e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2415e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2416e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2417e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2418e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2419e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2420e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2421e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2422e279b6c1SSam Ravnborg 11) exchange RAM chips 2423e279b6c1SSam Ravnborg 12) exchange the motherboard. 2424e279b6c1SSam Ravnborg 2425e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2426e279b6c1SSam Ravnborg module will be called apm. 2427e279b6c1SSam Ravnborg 2428e279b6c1SSam Ravnborgif APM 2429e279b6c1SSam Ravnborg 2430e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2431e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 24328f9ca475SIngo Molnar ---help--- 2433e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2434e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2435e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2436e279b6c1SSam Ravnborg 2437e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2438e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2439e279b6c1SSam Ravnborg ---help--- 2440e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2441e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2442e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2443e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2444e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2445e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2446e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2447e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2448e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2449e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2450e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2451e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2452e279b6c1SSam Ravnborg this feature. 2453e279b6c1SSam Ravnborg 2454e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2455dd8af076SLen Brown depends on CPU_IDLE 2456e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 24578f9ca475SIngo Molnar ---help--- 2458e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2459e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2460e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2461e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2462e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2463e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2464e279b6c1SSam Ravnborg this option does nothing.) 2465e279b6c1SSam Ravnborg 2466e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2467e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 24688f9ca475SIngo Molnar ---help--- 2469e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2470e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2471e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2472e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2473e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2474e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2475e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2476e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2477e279b6c1SSam Ravnborg especially if you are using gpm. 2478e279b6c1SSam Ravnborg 2479e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2480e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 24818f9ca475SIngo Molnar ---help--- 2482e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2483e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2484e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2485e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2486e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2487e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2488e279b6c1SSam Ravnborg 2489e279b6c1SSam Ravnborgendif # APM 2490e279b6c1SSam Ravnborg 2491bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2492e279b6c1SSam Ravnborg 2493e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2494e279b6c1SSam Ravnborg 249527471fdbSAndy Henroidsource "drivers/idle/Kconfig" 249627471fdbSAndy Henroid 2497e279b6c1SSam Ravnborgendmenu 2498e279b6c1SSam Ravnborg 2499e279b6c1SSam Ravnborg 2500e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2501e279b6c1SSam Ravnborg 2502e279b6c1SSam Ravnborgconfig PCI 25031ac97018SIngo Molnar bool "PCI support" 25041c858087SAdrian Bunk default y 25058f9ca475SIngo Molnar ---help--- 2506e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2507e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2508e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2509e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2510e279b6c1SSam Ravnborg 2511e279b6c1SSam Ravnborgchoice 2512e279b6c1SSam Ravnborg prompt "PCI access mode" 2513efefa6f6SIngo Molnar depends on X86_32 && PCI 2514e279b6c1SSam Ravnborg default PCI_GOANY 2515e279b6c1SSam Ravnborg ---help--- 2516e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2517e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2518e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2519e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2520e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2521e279b6c1SSam Ravnborg 2522e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2523e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2524e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2525e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2526e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2527e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2528e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2529e279b6c1SSam Ravnborg 2530e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2531e279b6c1SSam Ravnborg bool "BIOS" 2532e279b6c1SSam Ravnborg 2533e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2534e279b6c1SSam Ravnborg bool "MMConfig" 2535e279b6c1SSam Ravnborg 2536e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2537e279b6c1SSam Ravnborg bool "Direct" 2538e279b6c1SSam Ravnborg 25393ef0e1f8SAndres Salomonconfig PCI_GOOLPC 254076fb6570SDaniel Drake bool "OLPC XO-1" 25413ef0e1f8SAndres Salomon depends on OLPC 25423ef0e1f8SAndres Salomon 25432bdd1b03SAndres Salomonconfig PCI_GOANY 25442bdd1b03SAndres Salomon bool "Any" 25452bdd1b03SAndres Salomon 2546e279b6c1SSam Ravnborgendchoice 2547e279b6c1SSam Ravnborg 2548e279b6c1SSam Ravnborgconfig PCI_BIOS 25493c2362e6SHarvey Harrison def_bool y 2550efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2551e279b6c1SSam Ravnborg 2552e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2553e279b6c1SSam Ravnborgconfig PCI_DIRECT 25543c2362e6SHarvey Harrison def_bool y 25550aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2556e279b6c1SSam Ravnborg 2557e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 25583c2362e6SHarvey Harrison def_bool y 25595f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2560e279b6c1SSam Ravnborg 25613ef0e1f8SAndres Salomonconfig PCI_OLPC 25622bdd1b03SAndres Salomon def_bool y 25632bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 25643ef0e1f8SAndres Salomon 2565b5401a96SAlex Nixonconfig PCI_XEN 2566b5401a96SAlex Nixon def_bool y 2567b5401a96SAlex Nixon depends on PCI && XEN 2568b5401a96SAlex Nixon select SWIOTLB_XEN 2569b5401a96SAlex Nixon 2570e279b6c1SSam Ravnborgconfig PCI_DOMAINS 25713c2362e6SHarvey Harrison def_bool y 2572e279b6c1SSam Ravnborg depends on PCI 2573e279b6c1SSam Ravnborg 2574e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2575e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2576e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2577e279b6c1SSam Ravnborg 25783f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 25796a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 25806ea30386SKees Cook depends on PCI 25813f6ea84aSIra W. Snyder help 25823f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 25833f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 25843f6ea84aSIra W. Snyder not have ACPI. 25853f6ea84aSIra W. Snyder 258664a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 258764a5fed6SBjorn Helgaas is known to be incomplete. 258864a5fed6SBjorn Helgaas 258964a5fed6SBjorn Helgaas You should say N unless you know you need this. 259064a5fed6SBjorn Helgaas 2591e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2592e279b6c1SSam Ravnborg 25933a495511SWilliam Breathitt Grayconfig ISA_BUS 25943a495511SWilliam Breathitt Gray bool "ISA-style bus support on modern systems" if EXPERT 25953a495511SWilliam Breathitt Gray select ISA_BUS_API 25963a495511SWilliam Breathitt Gray help 25973a495511SWilliam Breathitt Gray Enables ISA-style drivers on modern systems. This is necessary to 25983a495511SWilliam Breathitt Gray support PC/104 devices on X86_64 platforms. 25993a495511SWilliam Breathitt Gray 26003a495511SWilliam Breathitt Gray If unsure, say N. 26013a495511SWilliam Breathitt Gray 26021c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2603e279b6c1SSam Ravnborgconfig ISA_DMA_API 26041c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26051c00f016SDavid Rientjes default y 26061c00f016SDavid Rientjes help 26071c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26081c00f016SDavid Rientjes If unsure, say Y. 2609e279b6c1SSam Ravnborg 261051e68d05SLinus Torvaldsif X86_32 261151e68d05SLinus Torvalds 2612e279b6c1SSam Ravnborgconfig ISA 2613e279b6c1SSam Ravnborg bool "ISA support" 26148f9ca475SIngo Molnar ---help--- 2615e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2616e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2617e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2618e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2619e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2620e279b6c1SSam Ravnborg 2621e279b6c1SSam Ravnborgconfig EISA 2622e279b6c1SSam Ravnborg bool "EISA support" 2623e279b6c1SSam Ravnborg depends on ISA 2624e279b6c1SSam Ravnborg ---help--- 2625e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2626e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2627e279b6c1SSam Ravnborg 2628e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2629e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2630e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2631e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2632e279b6c1SSam Ravnborg 2633e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2634e279b6c1SSam Ravnborg 2635e279b6c1SSam Ravnborg Otherwise, say N. 2636e279b6c1SSam Ravnborg 2637e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2638e279b6c1SSam Ravnborg 2639e279b6c1SSam Ravnborgconfig SCx200 2640e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26418f9ca475SIngo Molnar ---help--- 2642e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2643e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2644e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2645e279b6c1SSam Ravnborg for other scx200_* drivers. 2646e279b6c1SSam Ravnborg 2647e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2648e279b6c1SSam Ravnborg 2649e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2650e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2651592913ecSJohn Stultz depends on SCx200 2652e279b6c1SSam Ravnborg default y 26538f9ca475SIngo Molnar ---help--- 2654e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2655e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2656e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2657e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2658e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2659e279b6c1SSam Ravnborg 26603ef0e1f8SAndres Salomonconfig OLPC 26613ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 266254008979SThomas Gleixner depends on !X86_PAE 26633c554946SAndres Salomon select GPIOLIB 2664dc3119e7SThomas Gleixner select OF 266545bb1674SDaniel Drake select OF_PROMTREE 2666b4e51854SGrant Likely select IRQ_DOMAIN 26678f9ca475SIngo Molnar ---help--- 26683ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 26693ef0e1f8SAndres Salomon XO hardware. 26703ef0e1f8SAndres Salomon 2671a3128588SDaniel Drakeconfig OLPC_XO1_PM 2672a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 267397c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2674a3128588SDaniel Drake select MFD_CORE 2675bf1ebf00SDaniel Drake ---help--- 267697c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2677bf1ebf00SDaniel Drake 2678cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2679cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2680cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2681cfee9597SDaniel Drake ---help--- 2682cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2683cfee9597SDaniel Drake programmable wakeup source. 2684cfee9597SDaniel Drake 26857feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 26867feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2687d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2688ed8e47feSRandy Dunlap depends on INPUT=y 2689d8d01a63SDaniel Drake select POWER_SUPPLY 26907feda8e9SDaniel Drake select GPIO_CS5535 26917feda8e9SDaniel Drake select MFD_CORE 26927feda8e9SDaniel Drake ---help--- 26937feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 26947bc74b3dSDaniel Drake - EC-driven system wakeups 26957feda8e9SDaniel Drake - Power button 26967bc74b3dSDaniel Drake - Ebook switch 26972cf2baeaSDaniel Drake - Lid switch 2698e1040ac6SDaniel Drake - AC adapter status updates 2699e1040ac6SDaniel Drake - Battery status updates 27007feda8e9SDaniel Drake 2701a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2702a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2703d8d01a63SDaniel Drake depends on OLPC && ACPI 2704d8d01a63SDaniel Drake select POWER_SUPPLY 2705a0f30f59SDaniel Drake ---help--- 2706a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2707a0f30f59SDaniel Drake - EC-driven system wakeups 2708a0f30f59SDaniel Drake - AC adapter status updates 2709a0f30f59SDaniel Drake - Battery status updates 2710e279b6c1SSam Ravnborg 2711d4f3e350SEd Wildgooseconfig ALIX 2712d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2713d4f3e350SEd Wildgoose select GPIOLIB 2714d4f3e350SEd Wildgoose ---help--- 2715d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2716d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2717d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2718d4f3e350SEd Wildgoose get added here. 2719d4f3e350SEd Wildgoose 2720d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2721d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2722d4f3e350SEd Wildgoose 2723d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2724d4f3e350SEd Wildgoose 2725da4e3302SPhilip Prindevilleconfig NET5501 2726da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2727da4e3302SPhilip Prindeville select GPIOLIB 2728da4e3302SPhilip Prindeville ---help--- 2729da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2730da4e3302SPhilip Prindeville 27313197059aSPhilip A. Prindevilleconfig GEOS 27323197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27333197059aSPhilip A. Prindeville select GPIOLIB 27343197059aSPhilip A. Prindeville depends on DMI 27353197059aSPhilip A. Prindeville ---help--- 27363197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27373197059aSPhilip A. Prindeville 27387d029125SVivien Didelotconfig TS5500 27397d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27407d029125SVivien Didelot depends on MELAN 27417d029125SVivien Didelot select CHECK_SIGNATURE 27427d029125SVivien Didelot select NEW_LEDS 27437d029125SVivien Didelot select LEDS_CLASS 27447d029125SVivien Didelot ---help--- 27457d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27467d029125SVivien Didelot 2747e279b6c1SSam Ravnborgendif # X86_32 2748e279b6c1SSam Ravnborg 274923ac4ae8SAndreas Herrmannconfig AMD_NB 2750e279b6c1SSam Ravnborg def_bool y 27510e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2752e279b6c1SSam Ravnborg 2753e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2754e279b6c1SSam Ravnborg 2755388b78adSAlexandre Bounineconfig RAPIDIO 2756fdf90abcSAlexandre Bounine tristate "RapidIO support" 2757388b78adSAlexandre Bounine depends on PCI 2758388b78adSAlexandre Bounine default n 2759388b78adSAlexandre Bounine help 2760fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2761388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2762388b78adSAlexandre Bounine 2763388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2764388b78adSAlexandre Bounine 2765e3263ab3SDavid Herrmannconfig X86_SYSFB 2766e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2767e3263ab3SDavid Herrmann help 2768e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2769e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2770e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2771e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2772e3263ab3SDavid Herrmann to x86. 2773e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2774e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2775e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2776e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2777e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2778e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2779e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2780e3263ab3SDavid Herrmann 2781e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2782e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2783e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2784e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2785e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2786e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2787e3263ab3SDavid Herrmann incompatible with simplefb. 2788e3263ab3SDavid Herrmann 2789e3263ab3SDavid Herrmann If unsure, say Y. 2790e3263ab3SDavid Herrmann 2791e279b6c1SSam Ravnborgendmenu 2792e279b6c1SSam Ravnborg 2793e279b6c1SSam Ravnborg 2794e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2795e279b6c1SSam Ravnborg 2796e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2797e279b6c1SSam Ravnborg 2798e279b6c1SSam Ravnborgconfig IA32_EMULATION 2799e279b6c1SSam Ravnborg bool "IA32 Emulation" 2800e279b6c1SSam Ravnborg depends on X86_64 280139f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2802d1603990SRandy Dunlap select BINFMT_ELF 2803a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 280439f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28058f9ca475SIngo Molnar ---help--- 28065fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28075fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28085fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2809e279b6c1SSam Ravnborg 2810e279b6c1SSam Ravnborgconfig IA32_AOUT 2811e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28126b213e1bSDavid Woodhouse depends on IA32_EMULATION 28138f9ca475SIngo Molnar ---help--- 2814e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2815e279b6c1SSam Ravnborg 28160bf62763SH. Peter Anvinconfig X86_X32 28176ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28189b54050bSBrian Gerst depends on X86_64 28195fd92e65SH. J. Lu ---help--- 28205fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28215fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28225fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28235fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28245fd92e65SH. J. Lu 28255fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 28265fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 28275fd92e65SH. J. Lu option set. 28285fd92e65SH. J. Lu 2829953fee1dSIngo Molnarconfig COMPAT_32 2830953fee1dSIngo Molnar def_bool y 2831953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2832953fee1dSIngo Molnar select HAVE_UID16 2833953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2834953fee1dSIngo Molnar 2835e279b6c1SSam Ravnborgconfig COMPAT 28363c2362e6SHarvey Harrison def_bool y 28370bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2838e279b6c1SSam Ravnborg 28393120e25eSJan Beulichif COMPAT 2840e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28413120e25eSJan Beulich def_bool y 2842e279b6c1SSam Ravnborg 2843e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28443c2362e6SHarvey Harrison def_bool y 28453120e25eSJan Beulich depends on SYSVIPC 28463120e25eSJan Beulichendif 2847ee009e4aSDavid Howells 2848e279b6c1SSam Ravnborgendmenu 2849e279b6c1SSam Ravnborg 2850e279b6c1SSam Ravnborg 2851e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2852e5beae16SKeith Packard def_bool y 2853e5beae16SKeith Packard depends on X86_32 2854e5beae16SKeith Packard 28554692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28564692d77fSAlessandro Rubini bool 285783125a3aSAlessandro Rubini depends on X86_64 || STA2X11 28584692d77fSAlessandro Rubini 2859f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2860f7219a53SAlessandro Rubini bool 286183125a3aSAlessandro Rubini depends on STA2X11 2862f7219a53SAlessandro Rubini 2863e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2864e585513bSKirill A. Shutemov def_bool y 2865e585513bSKirill A. Shutemov 2866e279b6c1SSam Ravnborgsource "net/Kconfig" 2867e279b6c1SSam Ravnborg 2868e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2869e279b6c1SSam Ravnborg 2870e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2871e279b6c1SSam Ravnborg 2872e279b6c1SSam Ravnborgsource "fs/Kconfig" 2873e279b6c1SSam Ravnborg 2874e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2875e279b6c1SSam Ravnborg 2876e279b6c1SSam Ravnborgsource "security/Kconfig" 2877e279b6c1SSam Ravnborg 2878e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2879e279b6c1SSam Ravnborg 2880edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2881edf88417SAvi Kivity 2882e279b6c1SSam Ravnborgsource "lib/Kconfig" 2883