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 950fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 96ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 976471b825SIngo Molnar select GENERIC_IRQ_PROBE 98*c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 996471b825SIngo Molnar select GENERIC_IRQ_SHOW 1006471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1016471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1026471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1036471b825SIngo Molnar select GENERIC_STRNLEN_USER 1046471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1057edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1066471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1076471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1086471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1096471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1106471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1116471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 1126471b825SIngo Molnar select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 1136471b825SIngo Molnar select HAVE_ARCH_KGDB 1146471b825SIngo Molnar select HAVE_ARCH_KMEMCHECK 1159e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1169e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1171b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1186471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 1196471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1206471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 121a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 122e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 123c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1246471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1256471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1266471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1276471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 128c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1296471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1306471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1316471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1326471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1339c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 134677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 13506aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 136c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 13758340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1385f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 139644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1406471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1416471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1426471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1436b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1440067f129SK.Prasad select HAVE_HW_BREAKPOINT 1456471b825SIngo Molnar select HAVE_IDE 1466471b825SIngo Molnar select HAVE_IOREMAP_PROT 1476471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1486471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1496471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1506471b825SIngo Molnar select HAVE_KERNEL_GZIP 1516471b825SIngo Molnar select HAVE_KERNEL_LZ4 1526471b825SIngo Molnar select HAVE_KERNEL_LZMA 1536471b825SIngo Molnar select HAVE_KERNEL_LZO 1546471b825SIngo Molnar select HAVE_KERNEL_XZ 1556471b825SIngo Molnar select HAVE_KPROBES 1566471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 1576471b825SIngo Molnar select HAVE_KRETPROBES 1586471b825SIngo Molnar select HAVE_KVM 1596471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1606471b825SIngo Molnar select HAVE_MEMBLOCK 1616471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1620102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 163ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 16442a0bb3fSPetr Mladek select HAVE_NMI 1656471b825SIngo Molnar select HAVE_OPROFILE 1666471b825SIngo Molnar select HAVE_OPTPROBES 1676471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1686471b825SIngo Molnar select HAVE_PERF_EVENTS 169c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 17092e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 171c5e63197SJiri Olsa select HAVE_PERF_REGS 172c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1739e52fc2bSVitaly Kuznetsov select HAVE_RCU_TABLE_FREE 1746471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 17581d38719SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && FRAME_POINTER_UNWINDER && STACK_VALIDATION 176c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1776471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1786471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1797c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 180c0185808SThomas Gleixner select IRQ_FORCED_THREADING 181df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1826471b825SIngo Molnar select PERF_EVENTS 1833195ef59SPrarit Bhargava select RTC_LIB 184d6faca40SArnd Bergmann select RTC_MC146818_LIB 1856471b825SIngo Molnar select SPARSE_IRQ 18683fe27eaSPranith Kumar select SRCU 1876471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 18815f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1896471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1906471b825SIngo Molnar select VIRT_TO_BUS 1916471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1927d8330a5SBalbir Singh 193ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1943120e25eSJan Beulich def_bool y 1953120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 196ba7e4d13SIngo Molnar 19751b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 19851b26adaSLinus Torvalds string 19951b26adaSLinus Torvalds default "elf32-i386" if X86_32 20051b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 20151b26adaSLinus Torvalds 20273531905SSam Ravnborgconfig ARCH_DEFCONFIG 203b9b39bfbSSam Ravnborg string 20473531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 20573531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 206b9b39bfbSSam Ravnborg 2078d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2083c2362e6SHarvey Harrison def_bool y 2098d5fffb9SSam Ravnborg 2108d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2113c2362e6SHarvey Harrison def_bool y 2128d5fffb9SSam Ravnborg 2138d5fffb9SSam Ravnborgconfig MMU 2143c2362e6SHarvey Harrison def_bool y 2158d5fffb9SSam Ravnborg 2169e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2179e08f57dSDaniel Cashman default 28 if 64BIT 2189e08f57dSDaniel Cashman default 8 2199e08f57dSDaniel Cashman 2209e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2219e08f57dSDaniel Cashman default 32 if 64BIT 2229e08f57dSDaniel Cashman default 16 2239e08f57dSDaniel Cashman 2249e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2259e08f57dSDaniel Cashman default 8 2269e08f57dSDaniel Cashman 2279e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2289e08f57dSDaniel Cashman default 16 2299e08f57dSDaniel Cashman 2308d5fffb9SSam Ravnborgconfig SBUS 2318d5fffb9SSam Ravnborg bool 2328d5fffb9SSam Ravnborg 2333bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2343120e25eSJan Beulich def_bool y 235a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2363bc4e459SFUJITA Tomonori 23718e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2384a14d84eSAndrew Morton def_bool y 23918e98307SFUJITA Tomonori 2408d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2413120e25eSJan Beulich def_bool y 2423120e25eSJan Beulich depends on ISA_DMA_API 2438d5fffb9SSam Ravnborg 2448d5fffb9SSam Ravnborgconfig GENERIC_BUG 2453c2362e6SHarvey Harrison def_bool y 2468d5fffb9SSam Ravnborg depends on BUG 247b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 248b93a531eSJan Beulich 249b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 250b93a531eSJan Beulich bool 2518d5fffb9SSam Ravnborg 2528d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2533c2362e6SHarvey Harrison def_bool y 2548d5fffb9SSam Ravnborg 2558d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2563120e25eSJan Beulich def_bool y 2573120e25eSJan Beulich depends on ISA_DMA_API 2588d5fffb9SSam Ravnborg 2591032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2603120e25eSJan Beulich def_bool y 2611032c0baSSam Ravnborg 2621032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2631032c0baSSam Ravnborg def_bool y 2641032c0baSSam Ravnborg 2659a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2669a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2678d5fffb9SSam Ravnborg 2681b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2691b27d05bSPekka Enberg def_bool y 2701b27d05bSPekka Enberg 271dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 27289c9c4c5SBrian Gerst def_bool y 273b32ef636Stravis@sgi.com 27408fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 27508fc4580STejun Heo def_bool y 27608fc4580STejun Heo 27708fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 27811124411STejun Heo def_bool y 27911124411STejun Heo 280801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 281801e4062SJohannes Berg def_bool y 282801e4062SJohannes Berg 283f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 284f4cb5700SJohannes Berg def_bool y 285f4cb5700SJohannes Berg 286cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 287cfe28c5dSSteve Capper def_bool y 288cfe28c5dSSteve Capper 28953313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 29053313b2cSSteve Capper def_bool y 29153313b2cSSteve Capper 2928d5fffb9SSam Ravnborgconfig ZONE_DMA32 293e0fd24a3SJan Beulich def_bool y if X86_64 2948d5fffb9SSam Ravnborg 2958d5fffb9SSam Ravnborgconfig AUDIT_ARCH 296e0fd24a3SJan Beulich def_bool y if X86_64 2978d5fffb9SSam Ravnborg 298765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 299765c68bdSIngo Molnar def_bool y 300765c68bdSIngo Molnar 3016a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3026a11f75bSAkinobu Mita def_bool y 3036a11f75bSAkinobu Mita 304d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 305d6f2d75aSAndrey Ryabinin hex 306d6f2d75aSAndrey Ryabinin depends on KASAN 3074c7c4483SKirill A. Shutemov default 0xdff8000000000000 if X86_5LEVEL 308d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 309d6f2d75aSAndrey Ryabinin 31069575d38SShane Wangconfig HAVE_INTEL_TXT 31169575d38SShane Wang def_bool y 3126ea30386SKees Cook depends on INTEL_IOMMU && ACPI 31369575d38SShane Wang 3146b0c3d44SSam Ravnborgconfig X86_32_SMP 3156b0c3d44SSam Ravnborg def_bool y 3166b0c3d44SSam Ravnborg depends on X86_32 && SMP 3176b0c3d44SSam Ravnborg 3186b0c3d44SSam Ravnborgconfig X86_64_SMP 3196b0c3d44SSam Ravnborg def_bool y 3206b0c3d44SSam Ravnborg depends on X86_64 && SMP 3216b0c3d44SSam Ravnborg 322ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 323ccbeed3aSTejun Heo def_bool y 32460a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 325ccbeed3aSTejun Heo 3262b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3272b144498SSrikar Dronamraju def_bool y 3282b144498SSrikar Dronamraju 329d20642f0SRob Herringconfig FIX_EARLYCON_MEM 330d20642f0SRob Herring def_bool y 331d20642f0SRob Herring 33298233368SKirill A. Shutemovconfig PGTABLE_LEVELS 33398233368SKirill A. Shutemov int 33477ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 33598233368SKirill A. Shutemov default 4 if X86_64 33698233368SKirill A. Shutemov default 3 if X86_PAE 33798233368SKirill A. Shutemov default 2 33898233368SKirill A. Shutemov 339506f1d07SSam Ravnborgsource "init/Kconfig" 340dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3418d5fffb9SSam Ravnborg 342506f1d07SSam Ravnborgmenu "Processor type and features" 343506f1d07SSam Ravnborg 3445ee71535SRandy Dunlapconfig ZONE_DMA 3455ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3465ee71535SRandy Dunlap default y 3475ee71535SRandy Dunlap help 3485ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3495ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3505ee71535SRandy Dunlap Disable if no such devices will be used. 3515ee71535SRandy Dunlap 3525ee71535SRandy Dunlap If unsure, say Y. 3535ee71535SRandy Dunlap 354506f1d07SSam Ravnborgconfig SMP 355506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 356506f1d07SSam Ravnborg ---help--- 357506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3584a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3594a474157SRobert Graffham than one CPU, say Y. 360506f1d07SSam Ravnborg 3614a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 362506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 363506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3644a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 365506f1d07SSam Ravnborg will run faster if you say N here. 366506f1d07SSam Ravnborg 367506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 368506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 369506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 370506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 371506f1d07SSam Ravnborg 372506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 373506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 374506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 375506f1d07SSam Ravnborg 376395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 377c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 378506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 379506f1d07SSam Ravnborg 380506f1d07SSam Ravnborg If you don't know what to do here, say N. 381506f1d07SSam Ravnborg 3829def39beSJosh Triplettconfig X86_FEATURE_NAMES 3839def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3849def39beSJosh Triplett default y 3859def39beSJosh Triplett ---help--- 3869def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3879def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3889def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3899def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3909def39beSJosh Triplett 3919def39beSJosh Triplett If in doubt, say Y. 3929def39beSJosh Triplett 3936e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3946e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3956e1315feSBorislav Petkov default y 3966e1315feSBorislav Petkov ---help--- 3976e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 3986e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 3996e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 4006e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 4016e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 4026e1315feSBorislav Petkov slower code. 4036e1315feSBorislav Petkov 40406cd9a7dSYinghai Luconfig X86_X2APIC 40506cd9a7dSYinghai Lu bool "Support x2apic" 40619e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 40706cd9a7dSYinghai Lu ---help--- 40806cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40906cd9a7dSYinghai Lu 41006cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 41106cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 41206cd9a7dSYinghai Lu 41306cd9a7dSYinghai Lu If you don't know what to do here, say N. 41406cd9a7dSYinghai Lu 4156695c85bSYinghai Luconfig X86_MPPARSE 4166e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4177a527688SJan Beulich default y 4185ab74722SIngo Molnar depends on X86_LOCAL_APIC 4198f9ca475SIngo Molnar ---help--- 4206695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4216695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4226695c85bSYinghai Lu 42326f7ef14SYinghai Luconfig X86_BIGSMP 42426f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 42526f7ef14SYinghai Lu depends on X86_32 && SMP 4268f9ca475SIngo Molnar ---help--- 42726f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 428506f1d07SSam Ravnborg 429ddd70cf9SJun Nakajimaconfig GOLDFISH 430ddd70cf9SJun Nakajima def_bool y 431ddd70cf9SJun Nakajima depends on X86_GOLDFISH 432ddd70cf9SJun Nakajima 433f01d7d51SVikas Shivappaconfig INTEL_RDT 434f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 43578e99b4aSFenghua Yu default n 43678e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 43759fe5a77SThomas Gleixner select KERNFS 43878e99b4aSFenghua Yu help 439f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 440f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 441f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 442f01d7d51SVikas Shivappa Architecture Software Developer Manual. 44378e99b4aSFenghua Yu 44478e99b4aSFenghua Yu Say N if unsure. 44578e99b4aSFenghua Yu 4468425091fSRavikiran G Thirumalaiif X86_32 447c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 448c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 449c5c606d9SRavikiran G Thirumalai default y 4508f9ca475SIngo Molnar ---help--- 45106ac8346SIngo Molnar If you disable this option then the kernel will only support 45206ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 45306ac8346SIngo Molnar systems out there.) 45406ac8346SIngo Molnar 4558425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4568425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 457cb7b8023SBen Hutchings Goldfish (Android emulator) 4588425091fSRavikiran G Thirumalai AMD Elan 4598425091fSRavikiran G Thirumalai RDC R-321x SoC 4608425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 46183125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4623f4110a4SThomas Gleixner Moorestown MID devices 46306ac8346SIngo Molnar 46406ac8346SIngo Molnar If you have one of these systems, or if you want to build a 46506ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4668425091fSRavikiran G Thirumalaiendif 46706ac8346SIngo Molnar 4688425091fSRavikiran G Thirumalaiif X86_64 4698425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4708425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4718425091fSRavikiran G Thirumalai default y 4728425091fSRavikiran G Thirumalai ---help--- 4738425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4748425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4758425091fSRavikiran G Thirumalai systems out there.) 4768425091fSRavikiran G Thirumalai 4778425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4788425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 47944b111b5SSteffen Persvold Numascale NumaChip 4808425091fSRavikiran G Thirumalai ScaleMP vSMP 4818425091fSRavikiran G Thirumalai SGI Ultraviolet 4828425091fSRavikiran G Thirumalai 4838425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4848425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4858425091fSRavikiran G Thirumalaiendif 486c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 487c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 48844b111b5SSteffen Persvoldconfig X86_NUMACHIP 48944b111b5SSteffen Persvold bool "Numascale NumaChip" 49044b111b5SSteffen Persvold depends on X86_64 49144b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 49244b111b5SSteffen Persvold depends on NUMA 49344b111b5SSteffen Persvold depends on SMP 49444b111b5SSteffen Persvold depends on X86_X2APIC 495f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 49644b111b5SSteffen Persvold ---help--- 49744b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 49844b111b5SSteffen Persvold enable more than ~168 cores. 49944b111b5SSteffen Persvold If you don't have one of these, you should say N here. 50003b48632SNick Piggin 5016a48565eSIngo Molnarconfig X86_VSMP 502c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5036276a074SBorislav Petkov select HYPERVISOR_GUEST 5046a48565eSIngo Molnar select PARAVIRT 5056a48565eSIngo Molnar depends on X86_64 && PCI 506c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 507ead91d4bSShai Fultheim depends on SMP 5088f9ca475SIngo Molnar ---help--- 5096a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5106a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5116a48565eSIngo Molnar if you have one of these machines. 5126a48565eSIngo Molnar 513c5c606d9SRavikiran G Thirumalaiconfig X86_UV 514c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 515c5c606d9SRavikiran G Thirumalai depends on X86_64 516c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 51754c28d29SJack Steiner depends on NUMA 5181ecb4ae5SAndrew Morton depends on EFI 5199d6c26e7SSuresh Siddha depends on X86_X2APIC 5201222e564SIngo Molnar depends on PCI 521c5c606d9SRavikiran G Thirumalai ---help--- 522c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 523c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 524c5c606d9SRavikiran G Thirumalai 525c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 526c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 527506f1d07SSam Ravnborg 528ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 529ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 530cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 531ddd70cf9SJun Nakajima ---help--- 532ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 533ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 534ddd70cf9SJun Nakajima Goldfish emulator say N here. 535ddd70cf9SJun Nakajima 536c751e17bSThomas Gleixnerconfig X86_INTEL_CE 537c751e17bSThomas Gleixner bool "CE4100 TV platform" 538c751e17bSThomas Gleixner depends on PCI 539c751e17bSThomas Gleixner depends on PCI_GODIRECT 5406084a6e2SJiang Liu depends on X86_IO_APIC 541c751e17bSThomas Gleixner depends on X86_32 542c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 54337bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 544da6b737bSSebastian Andrzej Siewior select OF 545da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 546c751e17bSThomas Gleixner ---help--- 547c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 548c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 549c751e17bSThomas Gleixner boxes and media devices. 550c751e17bSThomas Gleixner 5514cb9b00fSDavid Cohenconfig X86_INTEL_MID 55243605ef1SAlan Cox bool "Intel MID platform support" 55343605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 554edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5551ea7c673SAlan Cox depends on PCI 5563fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5571ea7c673SAlan Cox depends on X86_IO_APIC 5587c9c3a1eSAlan Cox select SFI 5594cb9b00fSDavid Cohen select I2C 5607c9c3a1eSAlan Cox select DW_APB_TIMER 5611ea7c673SAlan Cox select APB_TIMER 5621ea7c673SAlan Cox select INTEL_SCU_IPC 56315a713dfSMika Westerberg select MFD_INTEL_MSIC 5641ea7c673SAlan Cox ---help--- 5654cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5664cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5674cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5681ea7c673SAlan Cox 5694cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5704cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 57143605ef1SAlan Cox 5728bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5738bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5748bbc2a13SBryan O'Donoghue depends on X86_32 5758bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5768bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5778bbc2a13SBryan O'Donoghue depends on X86_TSC 5788bbc2a13SBryan O'Donoghue depends on PCI 5798bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5808bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5818bbc2a13SBryan O'Donoghue select IOSF_MBI 5828bbc2a13SBryan O'Donoghue select INTEL_IMR 5839ab6eb51SAndy Shevchenko select COMMON_CLK 5848bbc2a13SBryan O'Donoghue ---help--- 5858bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5868bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5878bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5888bbc2a13SBryan O'Donoghue 5893d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5903d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 591eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5923d48aab1SMika Westerberg select COMMON_CLK 5930f531431SMathias Nyman select PINCTRL 594eebb3e8dSAndy Shevchenko select IOSF_MBI 5953d48aab1SMika Westerberg ---help--- 5963d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 5973d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 5980f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 5990f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6003d48aab1SMika Westerberg 60192082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 60292082a88SKen Xue bool "AMD ACPI2Platform devices support" 60392082a88SKen Xue depends on ACPI 60492082a88SKen Xue select COMMON_CLK 60592082a88SKen Xue select PINCTRL 60692082a88SKen Xue ---help--- 60792082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 60892082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 60992082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 61092082a88SKen Xue implemented under PINCTRL subsystem. 61192082a88SKen Xue 612ced3ce76SDavid E. Boxconfig IOSF_MBI 613ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 614ced3ce76SDavid E. Box depends on PCI 615ced3ce76SDavid E. Box ---help--- 616ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 617ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 618ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 619ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 620ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 621ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 622ced3ce76SDavid E. Box This list is not meant to be exclusive. 623ced3ce76SDavid E. Box - BayTrail 624ced3ce76SDavid E. Box - Braswell 625ced3ce76SDavid E. Box - Quark 626ced3ce76SDavid E. Box 627ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 628ced3ce76SDavid E. Box 629ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 630ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 631ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 632ed2226bdSDavid E. Box ---help--- 633ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 634ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 635ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 636ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 637ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 638ed2226bdSDavid E. Box device they want to access. 639ed2226bdSDavid E. Box 640ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 641ed2226bdSDavid E. Box 642c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 643c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 644506f1d07SSam Ravnborg depends on X86_32 645c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 646c5c606d9SRavikiran G Thirumalai select M486 647c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 648c5c606d9SRavikiran G Thirumalai ---help--- 649c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 650c5c606d9SRavikiran G Thirumalai as R-8610-(G). 651c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 652c5c606d9SRavikiran G Thirumalai 653e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6549c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6559c398017SIngo Molnar depends on X86_32 && SMP 656c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6578f9ca475SIngo Molnar ---help--- 658b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 659b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 660b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 661b5660ba7SH. Peter Anvin one and will fallback to default. 662d49c4288SYinghai Lu 663c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 664d49c4288SYinghai Lu 665d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6666fc108a0SJan Beulich def_bool y 667d949f36fSLinus Torvalds # MCE code calls memory_failure(): 668d949f36fSLinus Torvalds depends on X86_MCE 669d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 670d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 671d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 672d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 673d949f36fSLinus Torvalds 67483125a3aSAlessandro Rubiniconfig STA2X11 67583125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 67683125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 67783125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 67883125a3aSAlessandro Rubini select X86_DMA_REMAP 67983125a3aSAlessandro Rubini select SWIOTLB 68083125a3aSAlessandro Rubini select MFD_STA2X11 6810145071bSLinus Walleij select GPIOLIB 68283125a3aSAlessandro Rubini default n 68383125a3aSAlessandro Rubini ---help--- 68483125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 68583125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 68683125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 68783125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 68883125a3aSAlessandro Rubini standard PC machines. 68983125a3aSAlessandro Rubini 69082148d1dSShérabconfig X86_32_IRIS 69182148d1dSShérab tristate "Eurobraille/Iris poweroff module" 69282148d1dSShérab depends on X86_32 69382148d1dSShérab ---help--- 69482148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 69582148d1dSShérab to shut themselves down properly. A special I/O sequence is 69682148d1dSShérab needed to do so, which is what this module does at 69782148d1dSShérab kernel shutdown. 69882148d1dSShérab 69982148d1dSShérab This is only for Iris machines from EuroBraille. 70082148d1dSShérab 70182148d1dSShérab If unused, say N. 70282148d1dSShérab 703ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7043c2362e6SHarvey Harrison def_bool y 7053c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 706a87d0914SKen Chen depends on X86 7078f9ca475SIngo Molnar ---help--- 708506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 709506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 710506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 711506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 712506f1d07SSam Ravnborg 713506f1d07SSam Ravnborg If in doubt, say "Y". 714506f1d07SSam Ravnborg 7156276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7166276a074SBorislav Petkov bool "Linux guest support" 7178f9ca475SIngo Molnar ---help--- 7186276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7196276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7206276a074SBorislav Petkov setup. 721506f1d07SSam Ravnborg 7226276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7236276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 724506f1d07SSam Ravnborg 7256276a074SBorislav Petkovif HYPERVISOR_GUEST 726506f1d07SSam Ravnborg 727e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 728e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7298f9ca475SIngo Molnar ---help--- 730e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 731e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 732e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 733e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 734e61bd94aSEduardo Pereira Habkost 7356276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7366276a074SBorislav Petkov bool "paravirt-ops debugging" 7376276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7386276a074SBorislav Petkov ---help--- 7396276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7406276a074SBorislav Petkov a paravirt_op is missing when it is called. 7416276a074SBorislav Petkov 742b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 743b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7446ea30386SKees Cook depends on PARAVIRT && SMP 745b4ecc126SJeremy Fitzhardinge ---help--- 746b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 747b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 748b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 749b4ecc126SJeremy Fitzhardinge 7504c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7514c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 752b4ecc126SJeremy Fitzhardinge 7534c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 754b4ecc126SJeremy Fitzhardinge 75545e898b7SWaiman Longconfig QUEUED_LOCK_STAT 75645e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 757cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 75845e898b7SWaiman Long ---help--- 75945e898b7SWaiman Long Enable the collection of statistical data on the slowpath 76045e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 76145e898b7SWaiman Long them on debugfs. 76245e898b7SWaiman Long 7636276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7646276a074SBorislav Petkov 7656276a074SBorislav Petkovconfig KVM_GUEST 7666276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7676276a074SBorislav Petkov depends on PARAVIRT 7686276a074SBorislav Petkov select PARAVIRT_CLOCK 7696276a074SBorislav Petkov default y 7706276a074SBorislav Petkov ---help--- 7716276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7726276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7736276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7746276a074SBorislav Petkov underlying device model, the host provides the guest with 7756276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7766276a074SBorislav Petkov 7771e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7781e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7791e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7801e20eb85SSrivatsa Vaddagiri default n 7811e20eb85SSrivatsa Vaddagiri ---help--- 7821e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7831e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7841e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7851e20eb85SSrivatsa Vaddagiri 7866276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7876276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7886276a074SBorislav Petkov depends on PARAVIRT 7896276a074SBorislav Petkov default n 7906276a074SBorislav Petkov ---help--- 7916276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7926276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7936276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 7946276a074SBorislav Petkov that, there can be a small performance impact. 7956276a074SBorislav Petkov 7966276a074SBorislav Petkov If in doubt, say N here. 7976276a074SBorislav Petkov 7987af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 7997af192c9SGerd Hoffmann bool 8007af192c9SGerd Hoffmann 8016276a074SBorislav Petkovendif #HYPERVISOR_GUEST 80297349135SJeremy Fitzhardinge 80308677214SYinghai Luconfig NO_BOOTMEM 804774ea0bcSYinghai Lu def_bool y 80508677214SYinghai Lu 806506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 807506f1d07SSam Ravnborg 808506f1d07SSam Ravnborgconfig HPET_TIMER 8093c2362e6SHarvey Harrison def_bool X86_64 810506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8118f9ca475SIngo Molnar ---help--- 812506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 813506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 814506f1d07SSam Ravnborg present. 815506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 816506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 817506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8184e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8194e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 820506f1d07SSam Ravnborg 821506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 822506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 823506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 824506f1d07SSam Ravnborg 825506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 826506f1d07SSam Ravnborg 827506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8283c2362e6SHarvey Harrison def_bool y 8299d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 830506f1d07SSam Ravnborg 831bb24c471SJacob Panconfig APB_TIMER 832933b9463SAlan Cox def_bool y if X86_INTEL_MID 833933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 83406c3df49SJamie Iles select DW_APB_TIMER 835a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 836bb24c471SJacob Pan help 837bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 838bb24c471SJacob Pan The APBT provides a stable time base on SMP 839bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 840bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 841bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 842bb24c471SJacob Pan 8436a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 844506f1d07SSam Ravnborg# The code disables itself when not needed. 8457ae9392cSThomas Petazzoniconfig DMI 8467ae9392cSThomas Petazzoni default y 847cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8486a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8498f9ca475SIngo Molnar ---help--- 8507ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8517ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8527ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8537ae9392cSThomas Petazzoni BIOS code. 8547ae9392cSThomas Petazzoni 855506f1d07SSam Ravnborgconfig GART_IOMMU 85638901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 857506f1d07SSam Ravnborg select SWIOTLB 85823ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8598f9ca475SIngo Molnar ---help--- 860ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 861ced3c42cSIngo Molnar GART based hardware IOMMUs. 862ced3c42cSIngo Molnar 863ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 864ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 865ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 866ced3c42cSIngo Molnar 867ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 868ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 869ced3c42cSIngo Molnar 870ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 871ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 872ced3c42cSIngo Molnar 32-bit limited device. 873ced3c42cSIngo Molnar 874ced3c42cSIngo Molnar If unsure, say Y. 875506f1d07SSam Ravnborg 876506f1d07SSam Ravnborgconfig CALGARY_IOMMU 877506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 878506f1d07SSam Ravnborg select SWIOTLB 8796ea30386SKees Cook depends on X86_64 && PCI 8808f9ca475SIngo Molnar ---help--- 881506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 882506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 883506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 884506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 885506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 886506f1d07SSam Ravnborg prevents them from going anywhere except their intended 887506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 888506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 889506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 890506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 891506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 892506f1d07SSam Ravnborg If unsure, say Y. 893506f1d07SSam Ravnborg 894506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 8953c2362e6SHarvey Harrison def_bool y 8963c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 897506f1d07SSam Ravnborg depends on CALGARY_IOMMU 8988f9ca475SIngo Molnar ---help--- 899506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 900506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 901506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 902506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 903506f1d07SSam Ravnborg If unsure, say Y. 904506f1d07SSam Ravnborg 905506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 906506f1d07SSam Ravnborgconfig SWIOTLB 907a1afd01cSJoerg Roedel def_bool y if X86_64 9088f9ca475SIngo Molnar ---help--- 909506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9104454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9114454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9124454d327SJoe Millenbach with more than 3 GB of memory. 9134454d327SJoe Millenbach If unsure, say Y. 914506f1d07SSam Ravnborg 915a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9163120e25eSJan Beulich def_bool y 9173120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 918d25e26b6SLinus Torvalds 9191184dc2fSMike Travisconfig MAXSMP 920ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9216ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 92236f5101aSMike Travis select CPUMASK_OFFSTACK 9238f9ca475SIngo Molnar ---help--- 924ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9251184dc2fSMike Travis If unsure, say N. 926506f1d07SSam Ravnborg 927506f1d07SSam Ravnborgconfig NR_CPUS 92836f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 9292a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 930bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 931b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 93278637a97SMike Travis default "1" if !SMP 933b53b5edaSJosh Boyer default "8192" if MAXSMP 934b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 935c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 936c5c19941SKirill A. Shutemov default "64" if SMP 9378f9ca475SIngo Molnar ---help--- 938506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 939bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 940cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 941506f1d07SSam Ravnborg minimum value which makes sense is 2. 942506f1d07SSam Ravnborg 943506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 944506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 945506f1d07SSam Ravnborg 946506f1d07SSam Ravnborgconfig SCHED_SMT 947506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 948c8e56d20SBorislav Petkov depends on SMP 9498f9ca475SIngo Molnar ---help--- 950506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 951506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 952506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 953506f1d07SSam Ravnborg N here. 954506f1d07SSam Ravnborg 955506f1d07SSam Ravnborgconfig SCHED_MC 9563c2362e6SHarvey Harrison def_bool y 9573c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 958c8e56d20SBorislav Petkov depends on SMP 9598f9ca475SIngo Molnar ---help--- 960506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 961506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 962506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 963506f1d07SSam Ravnborg 964de966cf4STim Chenconfig SCHED_MC_PRIO 965de966cf4STim Chen bool "CPU core priorities scheduler support" 9660a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 9670a21fc12SIngo Molnar select X86_INTEL_PSTATE 9680a21fc12SIngo Molnar select CPU_FREQ 969de966cf4STim Chen default y 9705e76b2abSTim Chen ---help--- 971de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 972de966cf4STim Chen core ordering determined at manufacturing time, which allows 973de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 974de966cf4STim Chen single threaded workloads) than others. 975de966cf4STim Chen 976de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 977de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 978de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 979de966cf4STim Chen overall system performance can be achieved. 980de966cf4STim Chen 981de966cf4STim Chen This feature will have no effect on CPUs without this feature. 982de966cf4STim Chen 983de966cf4STim Chen If unsure say Y here. 9845e76b2abSTim Chen 985506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 986506f1d07SSam Ravnborg 98730b8b006SThomas Gleixnerconfig UP_LATE_INIT 98830b8b006SThomas Gleixner def_bool y 989ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 99030b8b006SThomas Gleixner 991506f1d07SSam Ravnborgconfig X86_UP_APIC 99250849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 99350849eefSJan Beulich default PCI_MSI 99438a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 9958f9ca475SIngo Molnar ---help--- 996506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 997506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 998506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 999506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1000506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1001506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1002506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1003506f1d07SSam Ravnborg lockups. 1004506f1d07SSam Ravnborg 1005506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1006506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1007506f1d07SSam Ravnborg depends on X86_UP_APIC 10088f9ca475SIngo Molnar ---help--- 1009506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1010506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1011506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1012506f1d07SSam Ravnborg 1013506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1014506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1015506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1016506f1d07SSam Ravnborg 1017506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10183c2362e6SHarvey Harrison def_bool y 10190dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1020b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 102152f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1022506f1d07SSam Ravnborg 1023506f1d07SSam Ravnborgconfig X86_IO_APIC 1024b1da1e71SJan Beulich def_bool y 1025b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1026506f1d07SSam Ravnborg 102741b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 102841b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 102941b9eb26SStefan Assmann depends on X86_IO_APIC 10308f9ca475SIngo Molnar ---help--- 103141b9eb26SStefan Assmann This option enables a workaround that fixes a source of 103241b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 103341b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 103441b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 103541b9eb26SStefan Assmann 103641b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 103741b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 103841b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 103941b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 104041b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 104141b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 104241b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 104341b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 104441b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 104541b9eb26SStefan Assmann down (vital) interrupt lines. 104641b9eb26SStefan Assmann 104741b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 104841b9eb26SStefan Assmann increased on these systems. 104941b9eb26SStefan Assmann 1050506f1d07SSam Ravnborgconfig X86_MCE 1051bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1052648ed940SChen, Gong select GENERIC_ALLOCATOR 1053e57dbaf7SBorislav Petkov default y 1054506f1d07SSam Ravnborg ---help--- 1055bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1056bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1057506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1058bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10594efc0670SAndi Kleen 10605de97c9fSTony Luckconfig X86_MCELOG_LEGACY 10615de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 10625de97c9fSTony Luck depends on X86_MCE 10635de97c9fSTony Luck ---help--- 10645de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 10655de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 10665de97c9fSTony Luck rasdaemon solution. 10675de97c9fSTony Luck 1068506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10693c2362e6SHarvey Harrison def_bool y 10703c2362e6SHarvey Harrison prompt "Intel MCE features" 1071c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10728f9ca475SIngo Molnar ---help--- 1073506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1074506f1d07SSam Ravnborg the thermal monitor. 1075506f1d07SSam Ravnborg 1076506f1d07SSam Ravnborgconfig X86_MCE_AMD 10773c2362e6SHarvey Harrison def_bool y 10783c2362e6SHarvey Harrison prompt "AMD MCE features" 1079f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 10808f9ca475SIngo Molnar ---help--- 1081506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1082506f1d07SSam Ravnborg the DRAM Error Threshold. 1083506f1d07SSam Ravnborg 10844efc0670SAndi Kleenconfig X86_ANCIENT_MCE 10856fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1086c31d9633SAndi Kleen depends on X86_32 && X86_MCE 10874efc0670SAndi Kleen ---help--- 10884efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 10895065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 10904efc0670SAndi Kleen line. 10914efc0670SAndi Kleen 1092b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1093b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 10946fc108a0SJan Beulich def_bool y 1095b2762686SAndi Kleen 1096ea149b36SAndi Kleenconfig X86_MCE_INJECT 1097bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1098ea149b36SAndi Kleen tristate "Machine check injector support" 1099ea149b36SAndi Kleen ---help--- 1100ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1101ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1102ea149b36SAndi Kleen QA it is safe to say n. 1103ea149b36SAndi Kleen 11044efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11054efc0670SAndi Kleen def_bool y 11065bb38adcSAndi Kleen depends on X86_MCE_INTEL 11074efc0670SAndi Kleen 110807dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1109e633c65aSKan Liang 11105aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11111e642812SIngo Molnar bool "Legacy VM86 support" 11125aef51c3SAndy Lutomirski default n 1113506f1d07SSam Ravnborg depends on X86_32 11148f9ca475SIngo Molnar ---help--- 11155aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11165aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11175aef51c3SAndy Lutomirski 11185aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11195aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11205aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11215aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11225aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11231e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11241e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11251e642812SIngo Molnar mode might be faster than emulation and you might want to 11261e642812SIngo Molnar enable this option. 11275aef51c3SAndy Lutomirski 11281e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11291e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11301e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11311e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11325aef51c3SAndy Lutomirski 11331e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11341e642812SIngo Molnar and slows down exception handling a tiny bit. 11355aef51c3SAndy Lutomirski 11361e642812SIngo Molnar If unsure, say N here. 11375aef51c3SAndy Lutomirski 11385aef51c3SAndy Lutomirskiconfig VM86 11395aef51c3SAndy Lutomirski bool 11405aef51c3SAndy Lutomirski default X86_LEGACY_VM86 114134273f41SH. Peter Anvin 114234273f41SH. Peter Anvinconfig X86_16BIT 114334273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 114434273f41SH. Peter Anvin default y 1145a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 114634273f41SH. Peter Anvin ---help--- 114734273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 114834273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 114934273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 115034273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 115134273f41SH. Peter Anvin 115234273f41SH. Peter Anvinconfig X86_ESPFIX32 115334273f41SH. Peter Anvin def_bool y 115434273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1155506f1d07SSam Ravnborg 1156197725deSH. Peter Anvinconfig X86_ESPFIX64 1157197725deSH. Peter Anvin def_bool y 115834273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1159506f1d07SSam Ravnborg 11601ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 11611ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 11621ad83c85SAndy Lutomirski default y 11631ad83c85SAndy Lutomirski depends on X86_64 11641ad83c85SAndy Lutomirski ---help--- 11651ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 11661ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 11671ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11681ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11691ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11701ad83c85SAndy Lutomirski 0xffffffffff600?00. 11711ad83c85SAndy Lutomirski 11721ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 11731ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 11741ad83c85SAndy Lutomirski 11751ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 11761ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 11771ad83c85SAndy Lutomirski 1178506f1d07SSam Ravnborgconfig TOSHIBA 1179506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1180506f1d07SSam Ravnborg depends on X86_32 1181506f1d07SSam Ravnborg ---help--- 1182506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1183506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1184506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1185506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1186506f1d07SSam Ravnborg 1187506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1188506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1189506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1190506f1d07SSam Ravnborg 1191506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1192506f1d07SSam Ravnborg Say N otherwise. 1193506f1d07SSam Ravnborg 1194506f1d07SSam Ravnborgconfig I8K 1195039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1196949a9d70SJean Delvare select HWMON 1197039ae585SPali Rohár select SENSORS_DELL_SMM 1198506f1d07SSam Ravnborg ---help--- 1199039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1200039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1201039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1202039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1203039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1204039ae585SPali Rohár needed userspace package i8kutils. 1205506f1d07SSam Ravnborg 1206039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1207039ae585SPali Rohár use userspace package i8kutils. 1208506f1d07SSam Ravnborg Say N otherwise. 1209506f1d07SSam Ravnborg 1210506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12119ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12129ba16087SJan Beulich depends on X86_32 1213506f1d07SSam Ravnborg ---help--- 1214506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1215506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1216506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1217506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1218506f1d07SSam Ravnborg system. 1219506f1d07SSam Ravnborg 1220506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12215e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1222506f1d07SSam Ravnborg 1223506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1224506f1d07SSam Ravnborg enable this option even if you don't need it. 1225506f1d07SSam Ravnborg Say N otherwise. 1226506f1d07SSam Ravnborg 1227506f1d07SSam Ravnborgconfig MICROCODE 12289a2bc335SBorislav Petkov bool "CPU microcode loading support" 12299a2bc335SBorislav Petkov default y 123080030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1231506f1d07SSam Ravnborg select FW_LOADER 1232506f1d07SSam Ravnborg ---help--- 1233506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12345f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12355f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12365f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12375f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12385f9c01aaSBorislav Petkov the Linux kernel. 1239506f1d07SSam Ravnborg 12405f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12415f9c01aaSBorislav Petkov in Documentation/x86/early-microcode.txt. For that you need to enable 12425f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12435f9c01aaSBorislav Petkov initrd for microcode blobs. 1244506f1d07SSam Ravnborg 12455f9c01aaSBorislav Petkov In addition, you can build-in the microcode into the kernel. For that you 12465f9c01aaSBorislav Petkov need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 12475f9c01aaSBorislav Petkov to the CONFIG_EXTRA_FIRMWARE config option. 1248506f1d07SSam Ravnborg 12498d86f390SPeter Orubaconfig MICROCODE_INTEL 1250e43f6e67SBorislav Petkov bool "Intel microcode loading support" 12518d86f390SPeter Oruba depends on MICROCODE 12528d86f390SPeter Oruba default MICROCODE 12538d86f390SPeter Oruba select FW_LOADER 12548f9ca475SIngo Molnar ---help--- 12558d86f390SPeter Oruba This options enables microcode patch loading support for Intel 12568d86f390SPeter Oruba processors. 12578d86f390SPeter Oruba 1258b8989db9SAlan For the current Intel microcode data package go to 1259b8989db9SAlan <https://downloadcenter.intel.com> and search for 1260b8989db9SAlan 'Linux Processor Microcode Data File'. 12618d86f390SPeter Oruba 126280cc9f10SPeter Orubaconfig MICROCODE_AMD 1263e43f6e67SBorislav Petkov bool "AMD microcode loading support" 126480cc9f10SPeter Oruba depends on MICROCODE 126580cc9f10SPeter Oruba select FW_LOADER 12668f9ca475SIngo Molnar ---help--- 126780cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 126880cc9f10SPeter Oruba processors will be enabled. 126980cc9f10SPeter Oruba 1270506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12713c2362e6SHarvey Harrison def_bool y 1272506f1d07SSam Ravnborg depends on MICROCODE 1273506f1d07SSam Ravnborg 1274506f1d07SSam Ravnborgconfig X86_MSR 1275506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 12768f9ca475SIngo Molnar ---help--- 1277506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1278506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1279506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1280506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1281506f1d07SSam Ravnborg systems. 1282506f1d07SSam Ravnborg 1283506f1d07SSam Ravnborgconfig X86_CPUID 1284506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 12858f9ca475SIngo Molnar ---help--- 1286506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1287506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1288506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1289506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1290506f1d07SSam Ravnborg 1291506f1d07SSam Ravnborgchoice 1292506f1d07SSam Ravnborg prompt "High Memory Support" 12936fc108a0SJan Beulich default HIGHMEM4G 1294506f1d07SSam Ravnborg depends on X86_32 1295506f1d07SSam Ravnborg 1296506f1d07SSam Ravnborgconfig NOHIGHMEM 1297506f1d07SSam Ravnborg bool "off" 1298506f1d07SSam Ravnborg ---help--- 1299506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1300506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1301506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1302506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1303506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1304506f1d07SSam Ravnborg "high memory". 1305506f1d07SSam Ravnborg 1306506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1307506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1308506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1309506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1310506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1311506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1312506f1d07SSam Ravnborg possible. 1313506f1d07SSam Ravnborg 1314506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1315506f1d07SSam Ravnborg answer "4GB" here. 1316506f1d07SSam Ravnborg 1317506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1318506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1319506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1320506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1321506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1322506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1323506f1d07SSam Ravnborg 1324506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1325506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1326506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1327506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1328506f1d07SSam Ravnborg kernel at boot time.) 1329506f1d07SSam Ravnborg 1330506f1d07SSam Ravnborg If unsure, say "off". 1331506f1d07SSam Ravnborg 1332506f1d07SSam Ravnborgconfig HIGHMEM4G 1333506f1d07SSam Ravnborg bool "4GB" 13348f9ca475SIngo Molnar ---help--- 1335506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1336506f1d07SSam Ravnborg gigabytes of physical RAM. 1337506f1d07SSam Ravnborg 1338506f1d07SSam Ravnborgconfig HIGHMEM64G 1339506f1d07SSam Ravnborg bool "64GB" 1340eb068e78SH. Peter Anvin depends on !M486 1341506f1d07SSam Ravnborg select X86_PAE 13428f9ca475SIngo Molnar ---help--- 1343506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1344506f1d07SSam Ravnborg gigabytes of physical RAM. 1345506f1d07SSam Ravnborg 1346506f1d07SSam Ravnborgendchoice 1347506f1d07SSam Ravnborg 1348506f1d07SSam Ravnborgchoice 13496a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1350506f1d07SSam Ravnborg default VMSPLIT_3G 1351506f1d07SSam Ravnborg depends on X86_32 13528f9ca475SIngo Molnar ---help--- 1353506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1354506f1d07SSam Ravnborg 1355506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1356506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1357506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1358506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1359506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1360506f1d07SSam Ravnborg available to user programs, making the address space there 1361506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1362506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1363506f1d07SSam Ravnborg kernel modules. 1364506f1d07SSam Ravnborg 1365506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1366506f1d07SSam Ravnborg option alone! 1367506f1d07SSam Ravnborg 1368506f1d07SSam Ravnborg config VMSPLIT_3G 1369506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1370506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1371506f1d07SSam Ravnborg depends on !X86_PAE 1372506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1373506f1d07SSam Ravnborg config VMSPLIT_2G 1374506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1375506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1376506f1d07SSam Ravnborg depends on !X86_PAE 1377506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1378506f1d07SSam Ravnborg config VMSPLIT_1G 1379506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1380506f1d07SSam Ravnborgendchoice 1381506f1d07SSam Ravnborg 1382506f1d07SSam Ravnborgconfig PAGE_OFFSET 1383506f1d07SSam Ravnborg hex 1384506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1385506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1386506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1387506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1388506f1d07SSam Ravnborg default 0xC0000000 1389506f1d07SSam Ravnborg depends on X86_32 1390506f1d07SSam Ravnborg 1391506f1d07SSam Ravnborgconfig HIGHMEM 13923c2362e6SHarvey Harrison def_bool y 1393506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1394506f1d07SSam Ravnborg 1395506f1d07SSam Ravnborgconfig X86_PAE 13969ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1397506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 13989d99c712SChristian Melki select SWIOTLB 13998f9ca475SIngo Molnar ---help--- 1400506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1401506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1402506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1403506f1d07SSam Ravnborg consumes more pagetable space per process. 1404506f1d07SSam Ravnborg 140577ef56e4SKirill A. Shutemovconfig X86_5LEVEL 140677ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 140777ef56e4SKirill A. Shutemov depends on X86_64 140877ef56e4SKirill A. Shutemov ---help--- 140977ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 141077ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 141177ef56e4SKirill A. Shutemov physical address space. 141277ef56e4SKirill A. Shutemov 141377ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 141477ef56e4SKirill A. Shutemov 141577ef56e4SKirill A. Shutemov Note: a kernel with this option enabled can only be booted 141677ef56e4SKirill A. Shutemov on machines that support the feature. 141777ef56e4SKirill A. Shutemov 141877ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 141977ef56e4SKirill A. Shutemov information. 142077ef56e4SKirill A. Shutemov 142177ef56e4SKirill A. Shutemov Say N if unsure. 142277ef56e4SKirill A. Shutemov 1423600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14243120e25eSJan Beulich def_bool y 14253120e25eSJan Beulich depends on X86_64 || X86_PAE 1426600715dcSJeremy Fitzhardinge 142766f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14283120e25eSJan Beulich def_bool y 14293120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 143066f2b061SFUJITA Tomonori 143110971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1432e5008abeSLuis R. Rodriguez def_bool y 1433e5008abeSLuis R. Rodriguez depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 14348f9ca475SIngo Molnar ---help--- 143510971ab2SIngo Molnar Certain kernel features effectively disable kernel 143610971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 143710971ab2SIngo Molnar supports them), so don't confuse the user by printing 143810971ab2SIngo Molnar that we have them enabled. 14399e899816SNick Piggin 14407744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 14417744ccdbSTom Lendacky def_bool y 14427744ccdbSTom Lendacky 14437744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 14447744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 14457744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 14467744ccdbSTom Lendacky ---help--- 14477744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 14487744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 14497744ccdbSTom Lendacky Encryption (SME). 14507744ccdbSTom Lendacky 14517744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 14527744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 14537744ccdbSTom Lendacky default y 14547744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 14557744ccdbSTom Lendacky ---help--- 14567744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 14577744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 14587744ccdbSTom Lendacky 14597744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 14607744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 14617744ccdbSTom Lendacky 14627744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 14637744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 14647744ccdbSTom Lendacky 1465f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1466f88a68faSTom Lendacky def_bool y 1467f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1468f88a68faSTom Lendacky 1469506f1d07SSam Ravnborg# Common NUMA Features 1470506f1d07SSam Ravnborgconfig NUMA 1471fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1472506f1d07SSam Ravnborg depends on SMP 1473b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1474b5660ba7SH. Peter Anvin default y if X86_BIGSMP 14758f9ca475SIngo Molnar ---help--- 1476506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1477fd51b2d7SKOSAKI Motohiro 1478506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1479506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1480506f1d07SSam Ravnborg NUMA awareness to the kernel. 1481506f1d07SSam Ravnborg 1482c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1483fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1484fd51b2d7SKOSAKI Motohiro 1485b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 14867cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1487fd51b2d7SKOSAKI Motohiro 1488fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1489506f1d07SSam Ravnborg 1490eec1d4faSHans Rosenfeldconfig AMD_NUMA 14913c2362e6SHarvey Harrison def_bool y 14923c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 14935da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 14948f9ca475SIngo Molnar ---help--- 1495eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1496eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1497eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1498eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1499eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1500506f1d07SSam Ravnborg 1501506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15023c2362e6SHarvey Harrison def_bool y 15033c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1504506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1505506f1d07SSam Ravnborg select ACPI_NUMA 15068f9ca475SIngo Molnar ---help--- 1507506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1508506f1d07SSam Ravnborg 15096ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15106ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15116ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15126ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15136ec6e0d9SSuresh Siddha# for details. 15146ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15156ec6e0d9SSuresh Siddha def_bool y 15166ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15176ec6e0d9SSuresh Siddha 1518506f1d07SSam Ravnborgconfig NUMA_EMU 1519506f1d07SSam Ravnborg bool "NUMA emulation" 15201b7e03efSTejun Heo depends on NUMA 15218f9ca475SIngo Molnar ---help--- 1522506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1523506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1524506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1525506f1d07SSam Ravnborg 1526506f1d07SSam Ravnborgconfig NODES_SHIFT 1527d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 152851591e31SDavid Rientjes range 1 10 152951591e31SDavid Rientjes default "10" if MAXSMP 1530506f1d07SSam Ravnborg default "6" if X86_64 1531506f1d07SSam Ravnborg default "3" 1532506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15338f9ca475SIngo Molnar ---help--- 15341184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1535692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1536506f1d07SSam Ravnborg 1537506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15383c2362e6SHarvey Harrison def_bool y 1539506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1540506f1d07SSam Ravnborg 1541506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 15423c2362e6SHarvey Harrison def_bool y 1543506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1544506f1d07SSam Ravnborg 1545506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1546506f1d07SSam Ravnborg def_bool y 15473b16651fSTejun Heo depends on X86_32 && !NUMA 1548506f1d07SSam Ravnborg 1549506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1550506f1d07SSam Ravnborg def_bool y 1551b263295dSChristoph Lameter depends on NUMA && X86_32 1552506f1d07SSam Ravnborg 1553506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1554506f1d07SSam Ravnborg def_bool y 1555b263295dSChristoph Lameter depends on NUMA && X86_32 1556b263295dSChristoph Lameter 1557506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1558506f1d07SSam Ravnborg def_bool y 15596ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1560506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1561506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1562506f1d07SSam Ravnborg 15633b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 15643b16651fSTejun Heo def_bool y 15653b16651fSTejun Heo depends on X86_64 15663b16651fSTejun Heo 1567506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1568506f1d07SSam Ravnborg def_bool y 1569b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1570506f1d07SSam Ravnborg 1571506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1572a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 15733120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1574a0842b70SToshi Kani help 1575a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1576a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1577a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1578506f1d07SSam Ravnborg 15793b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 15803b16651fSTejun Heo def_bool y 15813b16651fSTejun Heo depends on X86_64 && PROC_KCORE 15823b16651fSTejun Heo 1583a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1584a29815a3SAvi Kivity hex 1585a29815a3SAvi Kivity default 0 if X86_32 1586a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1587a29815a3SAvi Kivity 1588506f1d07SSam Ravnborgsource "mm/Kconfig" 1589506f1d07SSam Ravnborg 15907a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 15917a67832cSDan Williams bool 15927a67832cSDan Williams 1593ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 15947a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 15959f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 15969f53f9faSDan Williams depends on BLK_DEV 15977a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 15989f53f9faSDan Williams select LIBNVDIMM 1599ec776ef6SChristoph Hellwig help 1600ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1601ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1602ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1603ec776ef6SChristoph Hellwig they can be used for persistent storage. 1604ec776ef6SChristoph Hellwig 1605ec776ef6SChristoph Hellwig Say Y if unsure. 1606ec776ef6SChristoph Hellwig 1607506f1d07SSam Ravnborgconfig HIGHPTE 1608506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16096fc108a0SJan Beulich depends on HIGHMEM 16108f9ca475SIngo Molnar ---help--- 1611506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1612506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1613506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1614506f1d07SSam Ravnborg entries in high memory. 1615506f1d07SSam Ravnborg 16169f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16179f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16188f9ca475SIngo Molnar ---help--- 16199f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16209f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16219f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16229f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16239f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16249f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16259f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16268c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16279f077871SJeremy Fitzhardinge 16289f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16299f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16309f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16319f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16329f077871SJeremy Fitzhardinge 16339f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16349f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16359f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16369f077871SJeremy Fitzhardinge memory. 16379f077871SJeremy Fitzhardinge 1638c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1639c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1640c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1641c885df50SJeremy Fitzhardinge default y 16428f9ca475SIngo Molnar ---help--- 1643c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1644c885df50SJeremy Fitzhardinge on or off. 1645c885df50SJeremy Fitzhardinge 16469ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1647d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1648d0cd7425SH. Peter Anvin default 64 1649d0cd7425SH. Peter Anvin range 4 640 16508f9ca475SIngo Molnar ---help--- 1651d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1652fc381519SIngo Molnar 1653d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1654d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1655fc381519SIngo Molnar 1656d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1657d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1658d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1659d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1660fc381519SIngo Molnar 1661d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1662d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1663d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1664d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1665d0cd7425SH. Peter Anvin entire low memory range. 1666d0cd7425SH. Peter Anvin 1667d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1668d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1669d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1670d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1671d0cd7425SH. Peter Anvin typical corruption patterns. 1672d0cd7425SH. Peter Anvin 1673d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1674fc381519SIngo Molnar 1675506f1d07SSam Ravnborgconfig MATH_EMULATION 1676506f1d07SSam Ravnborg bool 1677a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1678506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1679506f1d07SSam Ravnborg ---help--- 1680506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1681506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1682506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1683506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1684506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1685506f1d07SSam Ravnborg coprocessor or this emulation. 1686506f1d07SSam Ravnborg 1687506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1688506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1689506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1690506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1691506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1692506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1693506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1694506f1d07SSam Ravnborg intend to use this kernel on different machines. 1695506f1d07SSam Ravnborg 1696506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1697506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1698506f1d07SSam Ravnborg 1699506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1700506f1d07SSam Ravnborg kernel, it won't hurt. 1701506f1d07SSam Ravnborg 1702506f1d07SSam Ravnborgconfig MTRR 17036fc108a0SJan Beulich def_bool y 17046a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1705506f1d07SSam Ravnborg ---help--- 1706506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1707506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1708506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1709506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1710506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1711506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1712506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1713506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1714506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1715506f1d07SSam Ravnborg 1716506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1717506f1d07SSam Ravnborg control registers on other processors can be easily supported 1718506f1d07SSam Ravnborg as well: 1719506f1d07SSam Ravnborg 1720506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1721506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1722506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1723506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1724506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1725506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1726506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1727506f1d07SSam Ravnborg 1728506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1729506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1730506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1731506f1d07SSam Ravnborg 1732506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1733506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1734506f1d07SSam Ravnborg 17357225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1736506f1d07SSam Ravnborg 173795ffa243SYinghai Luconfig MTRR_SANITIZER 17382ffb3501SYinghai Lu def_bool y 173995ffa243SYinghai Lu prompt "MTRR cleanup support" 174095ffa243SYinghai Lu depends on MTRR 17418f9ca475SIngo Molnar ---help--- 1742aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1743aba3728cSThomas Gleixner add writeback entries. 174495ffa243SYinghai Lu 1745aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1746692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1747aba3728cSThomas Gleixner mtrr_chunk_size. 174895ffa243SYinghai Lu 17492ffb3501SYinghai Lu If unsure, say Y. 175095ffa243SYinghai Lu 175195ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1752f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1753f5098d62SYinghai Lu range 0 1 1754f5098d62SYinghai Lu default "0" 175595ffa243SYinghai Lu depends on MTRR_SANITIZER 17568f9ca475SIngo Molnar ---help--- 1757f5098d62SYinghai Lu Enable mtrr cleanup default value 175895ffa243SYinghai Lu 175912031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 176012031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 176112031a62SYinghai Lu range 0 7 176212031a62SYinghai Lu default "1" 176312031a62SYinghai Lu depends on MTRR_SANITIZER 17648f9ca475SIngo Molnar ---help--- 176512031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1766aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 176712031a62SYinghai Lu 17682e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 17696fc108a0SJan Beulich def_bool y 17706a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 17712a8a2719SIngo Molnar depends on MTRR 17728f9ca475SIngo Molnar ---help--- 17732e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1774042b78e4SVenki Pallipadi 17752e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 17762e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 17772e5d9c85Svenkatesh.pallipadi@intel.com 17782e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1779042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 17802e5d9c85Svenkatesh.pallipadi@intel.com 17812e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 17822e5d9c85Svenkatesh.pallipadi@intel.com 178346cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 178446cf98cdSVenkatesh Pallipadi def_bool y 178546cf98cdSVenkatesh Pallipadi depends on X86_PAT 178646cf98cdSVenkatesh Pallipadi 1787628c6246SH. Peter Anvinconfig ARCH_RANDOM 1788628c6246SH. Peter Anvin def_bool y 1789628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1790628c6246SH. Peter Anvin ---help--- 1791628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1792628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1793628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1794628c6246SH. Peter Anvin secure hardware random number generator. 1795628c6246SH. Peter Anvin 179651ae4a2dSH. Peter Anvinconfig X86_SMAP 179751ae4a2dSH. Peter Anvin def_bool y 179851ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 179951ae4a2dSH. Peter Anvin ---help--- 180051ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 180151ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 180251ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 180351ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 180451ae4a2dSH. Peter Anvin 180551ae4a2dSH. Peter Anvin If unsure, say Y. 180651ae4a2dSH. Peter Anvin 180772e9b5feSDave Hansenconfig X86_INTEL_MPX 180872e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 180972e9b5feSDave Hansen def_bool n 1810df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1811df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1812df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 181372e9b5feSDave Hansen ---help--- 181472e9b5feSDave Hansen MPX provides hardware features that can be used in 181572e9b5feSDave Hansen conjunction with compiler-instrumented code to check 181672e9b5feSDave Hansen memory references. It is designed to detect buffer 181772e9b5feSDave Hansen overflow or underflow bugs. 181872e9b5feSDave Hansen 181972e9b5feSDave Hansen This option enables running applications which are 182072e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 182172e9b5feSDave Hansen itself inside the kernel or to protect the kernel 182272e9b5feSDave Hansen against bad memory references. 182372e9b5feSDave Hansen 182472e9b5feSDave Hansen Enabling this option will make the kernel larger: 182572e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 182672e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 182772e9b5feSDave Hansen will increase the kernel memory overhead of each 182872e9b5feSDave Hansen process and adds some branches to paths used during 182972e9b5feSDave Hansen exec() and munmap(). 183072e9b5feSDave Hansen 183172e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 183272e9b5feSDave Hansen 183372e9b5feSDave Hansen If unsure, say N. 183472e9b5feSDave Hansen 183535e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1836284244a9SDave Hansen prompt "Intel Memory Protection Keys" 183735e97790SDave Hansen def_bool y 1838284244a9SDave Hansen # Note: only available in 64-bit mode 183935e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 184052c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 184152c8e601SIngo Molnar select ARCH_HAS_PKEYS 1842284244a9SDave Hansen ---help--- 1843284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1844284244a9SDave Hansen page-based protections, but without requiring modification of the 1845284244a9SDave Hansen page tables when an application changes protection domains. 1846284244a9SDave Hansen 1847284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1848284244a9SDave Hansen 1849284244a9SDave Hansen If unsure, say y. 185035e97790SDave Hansen 1851506f1d07SSam Ravnborgconfig EFI 18529ba16087SJan Beulich bool "EFI runtime service support" 18535b83683fSHuang, Ying depends on ACPI 1854f6ce5002SSergey Vlasov select UCS2_STRING 1855022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1856506f1d07SSam Ravnborg ---help--- 18578b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1858506f1d07SSam Ravnborg available (such as the EFI variable services). 1859506f1d07SSam Ravnborg 18608b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 18618b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 18628b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 18638b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 18648b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 18658b2cb7a8SHuang, Ying platforms. 1866506f1d07SSam Ravnborg 1867291f3632SMatt Flemingconfig EFI_STUB 1868291f3632SMatt Fleming bool "EFI stub support" 1869b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 18707b2a583aSMatt Fleming select RELOCATABLE 1871291f3632SMatt Fleming ---help--- 1872291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1873291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1874291f3632SMatt Fleming 18754172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 18760c759662SMatt Fleming 18777d453eeeSMatt Flemingconfig EFI_MIXED 18787d453eeeSMatt Fleming bool "EFI mixed-mode support" 18797d453eeeSMatt Fleming depends on EFI_STUB && X86_64 18807d453eeeSMatt Fleming ---help--- 18817d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 18827d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 18837d453eeeSMatt Fleming mode. 18847d453eeeSMatt Fleming 18857d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 18867d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 18877d453eeeSMatt Fleming the EFI handover protocol must be used. 18887d453eeeSMatt Fleming 18897d453eeeSMatt Fleming If unsure, say N. 18907d453eeeSMatt Fleming 1891506f1d07SSam Ravnborgconfig SECCOMP 18923c2362e6SHarvey Harrison def_bool y 18933c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 18948f9ca475SIngo Molnar ---help--- 1895506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1896506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1897506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1898506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1899506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1900506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19019c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1902506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1903506f1d07SSam Ravnborg defined by each seccomp mode. 1904506f1d07SSam Ravnborg 1905506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1906506f1d07SSam Ravnborg 1907506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1908506f1d07SSam Ravnborg 1909506f1d07SSam Ravnborgconfig KEXEC 1910506f1d07SSam Ravnborg bool "kexec system call" 19112965faa5SDave Young select KEXEC_CORE 19128f9ca475SIngo Molnar ---help--- 1913506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1914506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1915506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1916506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1917506f1d07SSam Ravnborg 1918506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1919506f1d07SSam Ravnborg 1920506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1921506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1922bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1923bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1924bf220695SGeert Uytterhoeven made. 1925506f1d07SSam Ravnborg 192674ca317cSVivek Goyalconfig KEXEC_FILE 192774ca317cSVivek Goyal bool "kexec file based system call" 19282965faa5SDave Young select KEXEC_CORE 192974ca317cSVivek Goyal select BUILD_BIN2C 193074ca317cSVivek Goyal depends on X86_64 193174ca317cSVivek Goyal depends on CRYPTO=y 193274ca317cSVivek Goyal depends on CRYPTO_SHA256=y 193374ca317cSVivek Goyal ---help--- 193474ca317cSVivek Goyal This is new version of kexec system call. This system call is 193574ca317cSVivek Goyal file based and takes file descriptors as system call argument 193674ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 193774ca317cSVivek Goyal accepted by previous system call. 193874ca317cSVivek Goyal 19398e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 19408e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 194174ca317cSVivek Goyal depends on KEXEC_FILE 19428e7d8381SVivek Goyal ---help--- 19438e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1944d8eb8940SBorislav Petkov the kexec_file_load() syscall. 19458e7d8381SVivek Goyal 1946d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1947d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1948d8eb8940SBorislav Petkov loaded in order for this to work. 19498e7d8381SVivek Goyal 19508e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 19518e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 19528e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 19538e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 19548e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 19558e7d8381SVivek Goyal ---help--- 19568e7d8381SVivek Goyal Enable bzImage signature verification support. 19578e7d8381SVivek Goyal 1958506f1d07SSam Ravnborgconfig CRASH_DUMP 195904b69447SPavel Machek bool "kernel crash dumps" 1960506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 19618f9ca475SIngo Molnar ---help--- 1962506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1963506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1964506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1965506f1d07SSam Ravnborg a specially reserved region and then later executed after 1966506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1967506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1968506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1969506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1970506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1971506f1d07SSam Ravnborg 19723ab83521SHuang Yingconfig KEXEC_JUMP 19736ea30386SKees Cook bool "kexec jump" 1974fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 19758f9ca475SIngo Molnar ---help--- 197689081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 197789081d17SHuang Ying code in physical address mode via KEXEC 19783ab83521SHuang Ying 1979506f1d07SSam Ravnborgconfig PHYSICAL_START 19806a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1981ceefccc9SH. Peter Anvin default "0x1000000" 19828f9ca475SIngo Molnar ---help--- 1983506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1984506f1d07SSam Ravnborg 1985506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1986506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1987506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1988506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1989506f1d07SSam Ravnborg address. 1990506f1d07SSam Ravnborg 1991506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1992506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1993506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1994506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1995506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1996506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1997506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1998506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1999506f1d07SSam Ravnborg 2000ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2001ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2002ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2003ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2004ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2005ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2006ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2007ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2008ceefccc9SH. Peter Anvin for more details about crash dumps. 2009506f1d07SSam Ravnborg 2010506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2011506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2012506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2013506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2014506f1d07SSam Ravnborg is present because there are users out there who continue to use 2015506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2016506f1d07SSam Ravnborg line. 2017506f1d07SSam Ravnborg 2018506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2019506f1d07SSam Ravnborg 2020506f1d07SSam Ravnborgconfig RELOCATABLE 202126717808SH. Peter Anvin bool "Build a relocatable kernel" 202226717808SH. Peter Anvin default y 20238f9ca475SIngo Molnar ---help--- 2024506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2025506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2026506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2027506f1d07SSam Ravnborg but are discarded at runtime. 2028506f1d07SSam Ravnborg 2029506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2030506f1d07SSam Ravnborg must live at a different physical address than the primary 2031506f1d07SSam Ravnborg kernel. 2032506f1d07SSam Ravnborg 2033506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2034506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 20358ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2036506f1d07SSam Ravnborg 20378ab3820fSKees Cookconfig RANDOMIZE_BASE 2038e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 20398ab3820fSKees Cook depends on RELOCATABLE 20406807c846SIngo Molnar default y 20418ab3820fSKees Cook ---help--- 2042e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2043e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2044e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2045e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2046e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2047e8581e3dSBaoquan He code internals. 2048e8581e3dSBaoquan He 2049ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2050ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2051ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2052ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2053ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2054ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2055ed9f007eSKees Cook 2056ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2057ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2058ed9f007eSKees Cook 512MB (8 bits of entropy). 20598ab3820fSKees Cook 2060a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2061e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2062e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2063ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2064ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2065ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2066ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2067ed9f007eSKees Cook theoretically possible, but the implementations are further 2068ed9f007eSKees Cook limited due to memory layouts. 2069e8581e3dSBaoquan He 20706807c846SIngo Molnar If unsure, say Y. 2071da2b6fb9SKees Cook 20728ab3820fSKees Cook# Relocation on x86 needs some additional build support 2073845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2074845adf72SH. Peter Anvin def_bool y 20758ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2076845adf72SH. Peter Anvin 2077506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2078a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 20798ab3820fSKees Cook default "0x200000" 2080a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2081a0215061SKees Cook range 0x200000 0x1000000 if X86_64 20828f9ca475SIngo Molnar ---help--- 2083506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2084506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2085506f1d07SSam Ravnborg address which meets above alignment restriction. 2086506f1d07SSam Ravnborg 2087506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2088506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2089506f1d07SSam Ravnborg address aligned to above value and run from there. 2090506f1d07SSam Ravnborg 2091506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2092506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2093506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2094506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2095506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2096506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2097506f1d07SSam Ravnborg above alignment restrictions. 2098506f1d07SSam Ravnborg 2099a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2100a0215061SKees Cook this value must be a multiple of 0x200000. 2101a0215061SKees Cook 2102506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2103506f1d07SSam Ravnborg 21040483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21050483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21060483e1faSThomas Garnier depends on X86_64 21070483e1faSThomas Garnier depends on RANDOMIZE_BASE 21080483e1faSThomas Garnier default RANDOMIZE_BASE 21090483e1faSThomas Garnier ---help--- 21100483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21110483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21120483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21130483e1faSThomas Garnier 21140483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21150483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21160483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21170483e1faSThomas Garnier addresses for each memory section. 21180483e1faSThomas Garnier 21196807c846SIngo Molnar If unsure, say Y. 21200483e1faSThomas Garnier 212190397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 212290397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 212390397a41SThomas Garnier depends on RANDOMIZE_MEMORY 212490397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 212590397a41SThomas Garnier default "0x0" 212690397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 212790397a41SThomas Garnier range 0x0 0x40 212890397a41SThomas Garnier ---help--- 212990397a41SThomas Garnier Define the padding in terabytes added to the existing physical 213090397a41SThomas Garnier memory size during kernel memory randomization. It is useful 213190397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 213290397a41SThomas Garnier address randomization. 213390397a41SThomas Garnier 213490397a41SThomas Garnier If unsure, leave at the default value. 213590397a41SThomas Garnier 2136506f1d07SSam Ravnborgconfig HOTPLUG_CPU 21377c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 213840b31360SStephen Rothwell depends on SMP 2139506f1d07SSam Ravnborg ---help--- 21407c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 21417c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 21427c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 21437c13e6a3SDimitri Sivanich automatically on SMP systems. ) 21447c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2145506f1d07SSam Ravnborg 214680aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 214780aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 214880aa1dffSFenghua Yu default n 21492c922cd0SKees Cook depends on HOTPLUG_CPU 215080aa1dffSFenghua Yu ---help--- 215180aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 215280aa1dffSFenghua Yu 215380aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 215480aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 215580aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 215680aa1dffSFenghua Yu 215780aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 215880aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 215980aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 216080aa1dffSFenghua Yu 216180aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 216280aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 216380aa1dffSFenghua Yu 216480aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 216580aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 216680aa1dffSFenghua Yu be other CPU0 dependencies. 216780aa1dffSFenghua Yu 216880aa1dffSFenghua Yu Please make sure the dependencies are under your control before 216980aa1dffSFenghua Yu you enable this feature. 217080aa1dffSFenghua Yu 217180aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 217280aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 217380aa1dffSFenghua Yu parameter cpu0_hotplug. 217480aa1dffSFenghua Yu 2175a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2176a71c8bc5SFenghua Yu def_bool n 2177a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 21782c922cd0SKees Cook depends on HOTPLUG_CPU 2179a71c8bc5SFenghua Yu ---help--- 2180a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2181a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2182a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2183a71c8bc5SFenghua Yu 2184a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2185a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2186a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2187a71c8bc5SFenghua Yu 2188a71c8bc5SFenghua Yu If unsure, say N. 2189a71c8bc5SFenghua Yu 2190506f1d07SSam Ravnborgconfig COMPAT_VDSO 2191b0b49f26SAndy Lutomirski def_bool n 2192b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2193953fee1dSIngo Molnar depends on COMPAT_32 21948f9ca475SIngo Molnar ---help--- 2195b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2196b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2197b0b49f26SAndy Lutomirski indicated in its segment table. 2198e84446deSRandy Dunlap 2199b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2200b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2201b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2202b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2203b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2204506f1d07SSam Ravnborg 2205b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2206b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2207b0b49f26SAndy Lutomirski 2208b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2209b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2210b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2211b0b49f26SAndy Lutomirski 2212b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2213b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2214506f1d07SSam Ravnborg 22153dc33bd3SKees Cookchoice 22163dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22173dc33bd3SKees Cook depends on X86_64 22183dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 22193dc33bd3SKees Cook help 22203dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 22213dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 22223dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 22233dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22243dc33bd3SKees Cook 22253dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 22263dc33bd3SKees Cook line parameter vsyscall=[native|emulate|none]. 22273dc33bd3SKees Cook 22283dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22293dc33bd3SKees Cook static binaries, you can say None without a performance penalty 22303dc33bd3SKees Cook to improve security. 22313dc33bd3SKees Cook 22323dc33bd3SKees Cook If unsure, select "Emulate". 22333dc33bd3SKees Cook 22343dc33bd3SKees Cook config LEGACY_VSYSCALL_NATIVE 22353dc33bd3SKees Cook bool "Native" 22363dc33bd3SKees Cook help 22373dc33bd3SKees Cook Actual executable code is located in the fixed vsyscall 22383dc33bd3SKees Cook address mapping, implementing time() efficiently. Since 22393dc33bd3SKees Cook this makes the mapping executable, it can be used during 22403dc33bd3SKees Cook security vulnerability exploitation (traditionally as 22413dc33bd3SKees Cook ROP gadgets). This configuration is not recommended. 22423dc33bd3SKees Cook 22433dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 22443dc33bd3SKees Cook bool "Emulate" 22453dc33bd3SKees Cook help 22463dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 22473dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 22483dc33bd3SKees Cook non-executable, but it still contains known contents, 22493dc33bd3SKees Cook which could be used in certain rare security vulnerability 22503dc33bd3SKees Cook exploits. This configuration is recommended when userspace 22513dc33bd3SKees Cook still uses the vsyscall area. 22523dc33bd3SKees Cook 22533dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 22543dc33bd3SKees Cook bool "None" 22553dc33bd3SKees Cook help 22563dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 22573dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 22583dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 22593dc33bd3SKees Cook will be reported to dmesg, so that either old or 22603dc33bd3SKees Cook malicious userspace programs can be identified. 22613dc33bd3SKees Cook 22623dc33bd3SKees Cookendchoice 22633dc33bd3SKees Cook 2264516cbf37STim Birdconfig CMDLINE_BOOL 2265516cbf37STim Bird bool "Built-in kernel command line" 22668f9ca475SIngo Molnar ---help--- 2267516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2268516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2269516cbf37STim Bird necessary or convenient to provide some or all of the 2270516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2271516cbf37STim Bird to not rely on the boot loader to provide them.) 2272516cbf37STim Bird 2273516cbf37STim Bird To compile command line arguments into the kernel, 2274516cbf37STim Bird set this option to 'Y', then fill in the 227569711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2276516cbf37STim Bird 2277516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2278516cbf37STim Bird should leave this option set to 'N'. 2279516cbf37STim Bird 2280516cbf37STim Birdconfig CMDLINE 2281516cbf37STim Bird string "Built-in kernel command string" 2282516cbf37STim Bird depends on CMDLINE_BOOL 2283516cbf37STim Bird default "" 22848f9ca475SIngo Molnar ---help--- 2285516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2286516cbf37STim Bird image and used at boot time. If the boot loader provides a 2287516cbf37STim Bird command line at boot time, it is appended to this string to 2288516cbf37STim Bird form the full kernel command line, when the system boots. 2289516cbf37STim Bird 2290516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2291516cbf37STim Bird change this behavior. 2292516cbf37STim Bird 2293516cbf37STim Bird In most cases, the command line (whether built-in or provided 2294516cbf37STim Bird by the boot loader) should specify the device for the root 2295516cbf37STim Bird file system. 2296516cbf37STim Bird 2297516cbf37STim Birdconfig CMDLINE_OVERRIDE 2298516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2299516cbf37STim Bird depends on CMDLINE_BOOL 23008f9ca475SIngo Molnar ---help--- 2301516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2302516cbf37STim Bird command line, and use ONLY the built-in command line. 2303516cbf37STim Bird 2304516cbf37STim Bird This is used to work around broken boot loaders. This should 2305516cbf37STim Bird be set to 'N' under normal conditions. 2306516cbf37STim Bird 2307a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2308a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2309a5b9e5a2SAndy Lutomirski default y 2310a5b9e5a2SAndy Lutomirski ---help--- 2311a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2312a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2313a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2314a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2315a5b9e5a2SAndy Lutomirski threading libraries. 2316a5b9e5a2SAndy Lutomirski 2317a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2318a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2319a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2320a5b9e5a2SAndy Lutomirski 2321a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2322a5b9e5a2SAndy Lutomirski 2323b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2324b700e7f0SSeth Jennings 2325506f1d07SSam Ravnborgendmenu 2326506f1d07SSam Ravnborg 23273072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 23283072e413SMichal Hocko def_bool y 23293072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 23303072e413SMichal Hocko 2331506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2332506f1d07SSam Ravnborg def_bool y 2333506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2334506f1d07SSam Ravnborg 233535551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 233635551053SGary Hade def_bool y 233735551053SGary Hade depends on MEMORY_HOTPLUG 233835551053SGary Hade 2339e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2340645a7919STejun Heo def_bool y 2341e534c7c5SLee Schermerhorn depends on NUMA 2342e534c7c5SLee Schermerhorn 23439491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 23449491846fSKirill A. Shutemov def_bool y 23459491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 23469491846fSKirill A. Shutemov 2347c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2348c177c81eSNaoya Horiguchi def_bool y 2349c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2350c177c81eSNaoya Horiguchi 23519c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 23529c670ea3SNaoya Horiguchi def_bool y 23539c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 23549c670ea3SNaoya Horiguchi 2355da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2356e279b6c1SSam Ravnborg 2357e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 23583c2362e6SHarvey Harrison def_bool y 2359e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2360e279b6c1SSam Ravnborg 2361e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2362e279b6c1SSam Ravnborg 2363e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2364e279b6c1SSam Ravnborg 2365efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2366efafc8b2SFeng Tang 2367a6b68076SAndi Kleenconfig X86_APM_BOOT 23686fc108a0SJan Beulich def_bool y 2369282e5aabSPaul Bolle depends on APM 2370a6b68076SAndi Kleen 2371e279b6c1SSam Ravnborgmenuconfig APM 2372e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2373efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2374e279b6c1SSam Ravnborg ---help--- 2375e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2376e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2377e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2378e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2379e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2380e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2381e279b6c1SSam Ravnborg 2382e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2383e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2384e279b6c1SSam Ravnborg 2385e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2386e279b6c1SSam Ravnborg machines with more than one CPU. 2387e279b6c1SSam Ravnborg 2388e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 23892dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 23902dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2391e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2392e279b6c1SSam Ravnborg 2393e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2394e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2395e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2396e279b6c1SSam Ravnborg 2397e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2398e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2399e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2400e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2401e279b6c1SSam Ravnborg 2402e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2403e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2404e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2405e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2406e279b6c1SSam Ravnborg APM in your BIOS). 2407e279b6c1SSam Ravnborg 2408e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2409e279b6c1SSam Ravnborg "weird" problems: 2410e279b6c1SSam Ravnborg 2411e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2412e279b6c1SSam Ravnborg enabled. 2413e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2414e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2415e279b6c1SSam Ravnborg the "no387" option to the kernel 2416e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2417e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2418e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2419e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2420e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2421e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2422e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2423e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2424e279b6c1SSam Ravnborg 11) exchange RAM chips 2425e279b6c1SSam Ravnborg 12) exchange the motherboard. 2426e279b6c1SSam Ravnborg 2427e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2428e279b6c1SSam Ravnborg module will be called apm. 2429e279b6c1SSam Ravnborg 2430e279b6c1SSam Ravnborgif APM 2431e279b6c1SSam Ravnborg 2432e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2433e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 24348f9ca475SIngo Molnar ---help--- 2435e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2436e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2437e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2438e279b6c1SSam Ravnborg 2439e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2440e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2441e279b6c1SSam Ravnborg ---help--- 2442e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2443e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2444e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2445e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2446e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2447e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2448e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2449e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2450e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2451e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2452e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2453e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2454e279b6c1SSam Ravnborg this feature. 2455e279b6c1SSam Ravnborg 2456e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2457dd8af076SLen Brown depends on CPU_IDLE 2458e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 24598f9ca475SIngo Molnar ---help--- 2460e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2461e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2462e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2463e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2464e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2465e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2466e279b6c1SSam Ravnborg this option does nothing.) 2467e279b6c1SSam Ravnborg 2468e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2469e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 24708f9ca475SIngo Molnar ---help--- 2471e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2472e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2473e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2474e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2475e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2476e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2477e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2478e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2479e279b6c1SSam Ravnborg especially if you are using gpm. 2480e279b6c1SSam Ravnborg 2481e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2482e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 24838f9ca475SIngo Molnar ---help--- 2484e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2485e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2486e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2487e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2488e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2489e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2490e279b6c1SSam Ravnborg 2491e279b6c1SSam Ravnborgendif # APM 2492e279b6c1SSam Ravnborg 2493bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2494e279b6c1SSam Ravnborg 2495e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2496e279b6c1SSam Ravnborg 249727471fdbSAndy Henroidsource "drivers/idle/Kconfig" 249827471fdbSAndy Henroid 2499e279b6c1SSam Ravnborgendmenu 2500e279b6c1SSam Ravnborg 2501e279b6c1SSam Ravnborg 2502e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2503e279b6c1SSam Ravnborg 2504e279b6c1SSam Ravnborgconfig PCI 25051ac97018SIngo Molnar bool "PCI support" 25061c858087SAdrian Bunk default y 25078f9ca475SIngo Molnar ---help--- 2508e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2509e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2510e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2511e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2512e279b6c1SSam Ravnborg 2513e279b6c1SSam Ravnborgchoice 2514e279b6c1SSam Ravnborg prompt "PCI access mode" 2515efefa6f6SIngo Molnar depends on X86_32 && PCI 2516e279b6c1SSam Ravnborg default PCI_GOANY 2517e279b6c1SSam Ravnborg ---help--- 2518e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2519e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2520e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2521e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2522e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2523e279b6c1SSam Ravnborg 2524e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2525e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2526e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2527e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2528e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2529e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2530e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2531e279b6c1SSam Ravnborg 2532e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2533e279b6c1SSam Ravnborg bool "BIOS" 2534e279b6c1SSam Ravnborg 2535e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2536e279b6c1SSam Ravnborg bool "MMConfig" 2537e279b6c1SSam Ravnborg 2538e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2539e279b6c1SSam Ravnborg bool "Direct" 2540e279b6c1SSam Ravnborg 25413ef0e1f8SAndres Salomonconfig PCI_GOOLPC 254276fb6570SDaniel Drake bool "OLPC XO-1" 25433ef0e1f8SAndres Salomon depends on OLPC 25443ef0e1f8SAndres Salomon 25452bdd1b03SAndres Salomonconfig PCI_GOANY 25462bdd1b03SAndres Salomon bool "Any" 25472bdd1b03SAndres Salomon 2548e279b6c1SSam Ravnborgendchoice 2549e279b6c1SSam Ravnborg 2550e279b6c1SSam Ravnborgconfig PCI_BIOS 25513c2362e6SHarvey Harrison def_bool y 2552efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2553e279b6c1SSam Ravnborg 2554e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2555e279b6c1SSam Ravnborgconfig PCI_DIRECT 25563c2362e6SHarvey Harrison def_bool y 25570aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2558e279b6c1SSam Ravnborg 2559e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 25603c2362e6SHarvey Harrison def_bool y 25615f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2562e279b6c1SSam Ravnborg 25633ef0e1f8SAndres Salomonconfig PCI_OLPC 25642bdd1b03SAndres Salomon def_bool y 25652bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 25663ef0e1f8SAndres Salomon 2567b5401a96SAlex Nixonconfig PCI_XEN 2568b5401a96SAlex Nixon def_bool y 2569b5401a96SAlex Nixon depends on PCI && XEN 2570b5401a96SAlex Nixon select SWIOTLB_XEN 2571b5401a96SAlex Nixon 2572e279b6c1SSam Ravnborgconfig PCI_DOMAINS 25733c2362e6SHarvey Harrison def_bool y 2574e279b6c1SSam Ravnborg depends on PCI 2575e279b6c1SSam Ravnborg 2576e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2577e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2578e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2579e279b6c1SSam Ravnborg 25803f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 25816a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 25826ea30386SKees Cook depends on PCI 25833f6ea84aSIra W. Snyder help 25843f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 25853f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 25863f6ea84aSIra W. Snyder not have ACPI. 25873f6ea84aSIra W. Snyder 258864a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 258964a5fed6SBjorn Helgaas is known to be incomplete. 259064a5fed6SBjorn Helgaas 259164a5fed6SBjorn Helgaas You should say N unless you know you need this. 259264a5fed6SBjorn Helgaas 2593e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2594e279b6c1SSam Ravnborg 25953a495511SWilliam Breathitt Grayconfig ISA_BUS 25963a495511SWilliam Breathitt Gray bool "ISA-style bus support on modern systems" if EXPERT 25973a495511SWilliam Breathitt Gray select ISA_BUS_API 25983a495511SWilliam Breathitt Gray help 25993a495511SWilliam Breathitt Gray Enables ISA-style drivers on modern systems. This is necessary to 26003a495511SWilliam Breathitt Gray support PC/104 devices on X86_64 platforms. 26013a495511SWilliam Breathitt Gray 26023a495511SWilliam Breathitt Gray If unsure, say N. 26033a495511SWilliam Breathitt Gray 26041c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2605e279b6c1SSam Ravnborgconfig ISA_DMA_API 26061c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26071c00f016SDavid Rientjes default y 26081c00f016SDavid Rientjes help 26091c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26101c00f016SDavid Rientjes If unsure, say Y. 2611e279b6c1SSam Ravnborg 261251e68d05SLinus Torvaldsif X86_32 261351e68d05SLinus Torvalds 2614e279b6c1SSam Ravnborgconfig ISA 2615e279b6c1SSam Ravnborg bool "ISA support" 26168f9ca475SIngo Molnar ---help--- 2617e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2618e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2619e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2620e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2621e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2622e279b6c1SSam Ravnborg 2623e279b6c1SSam Ravnborgconfig EISA 2624e279b6c1SSam Ravnborg bool "EISA support" 2625e279b6c1SSam Ravnborg depends on ISA 2626e279b6c1SSam Ravnborg ---help--- 2627e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2628e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2629e279b6c1SSam Ravnborg 2630e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2631e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2632e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2633e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2634e279b6c1SSam Ravnborg 2635e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2636e279b6c1SSam Ravnborg 2637e279b6c1SSam Ravnborg Otherwise, say N. 2638e279b6c1SSam Ravnborg 2639e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2640e279b6c1SSam Ravnborg 2641e279b6c1SSam Ravnborgconfig SCx200 2642e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26438f9ca475SIngo Molnar ---help--- 2644e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2645e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2646e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2647e279b6c1SSam Ravnborg for other scx200_* drivers. 2648e279b6c1SSam Ravnborg 2649e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2650e279b6c1SSam Ravnborg 2651e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2652e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2653592913ecSJohn Stultz depends on SCx200 2654e279b6c1SSam Ravnborg default y 26558f9ca475SIngo Molnar ---help--- 2656e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2657e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2658e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2659e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2660e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2661e279b6c1SSam Ravnborg 26623ef0e1f8SAndres Salomonconfig OLPC 26633ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 266454008979SThomas Gleixner depends on !X86_PAE 26653c554946SAndres Salomon select GPIOLIB 2666dc3119e7SThomas Gleixner select OF 266745bb1674SDaniel Drake select OF_PROMTREE 2668b4e51854SGrant Likely select IRQ_DOMAIN 26698f9ca475SIngo Molnar ---help--- 26703ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 26713ef0e1f8SAndres Salomon XO hardware. 26723ef0e1f8SAndres Salomon 2673a3128588SDaniel Drakeconfig OLPC_XO1_PM 2674a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 267597c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2676a3128588SDaniel Drake select MFD_CORE 2677bf1ebf00SDaniel Drake ---help--- 267897c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2679bf1ebf00SDaniel Drake 2680cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2681cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2682cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2683cfee9597SDaniel Drake ---help--- 2684cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2685cfee9597SDaniel Drake programmable wakeup source. 2686cfee9597SDaniel Drake 26877feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 26887feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2689d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2690ed8e47feSRandy Dunlap depends on INPUT=y 2691d8d01a63SDaniel Drake select POWER_SUPPLY 26927feda8e9SDaniel Drake select GPIO_CS5535 26937feda8e9SDaniel Drake select MFD_CORE 26947feda8e9SDaniel Drake ---help--- 26957feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 26967bc74b3dSDaniel Drake - EC-driven system wakeups 26977feda8e9SDaniel Drake - Power button 26987bc74b3dSDaniel Drake - Ebook switch 26992cf2baeaSDaniel Drake - Lid switch 2700e1040ac6SDaniel Drake - AC adapter status updates 2701e1040ac6SDaniel Drake - Battery status updates 27027feda8e9SDaniel Drake 2703a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2704a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2705d8d01a63SDaniel Drake depends on OLPC && ACPI 2706d8d01a63SDaniel Drake select POWER_SUPPLY 2707a0f30f59SDaniel Drake ---help--- 2708a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2709a0f30f59SDaniel Drake - EC-driven system wakeups 2710a0f30f59SDaniel Drake - AC adapter status updates 2711a0f30f59SDaniel Drake - Battery status updates 2712e279b6c1SSam Ravnborg 2713d4f3e350SEd Wildgooseconfig ALIX 2714d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2715d4f3e350SEd Wildgoose select GPIOLIB 2716d4f3e350SEd Wildgoose ---help--- 2717d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2718d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2719d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2720d4f3e350SEd Wildgoose get added here. 2721d4f3e350SEd Wildgoose 2722d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2723d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2724d4f3e350SEd Wildgoose 2725d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2726d4f3e350SEd Wildgoose 2727da4e3302SPhilip Prindevilleconfig NET5501 2728da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2729da4e3302SPhilip Prindeville select GPIOLIB 2730da4e3302SPhilip Prindeville ---help--- 2731da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2732da4e3302SPhilip Prindeville 27333197059aSPhilip A. Prindevilleconfig GEOS 27343197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27353197059aSPhilip A. Prindeville select GPIOLIB 27363197059aSPhilip A. Prindeville depends on DMI 27373197059aSPhilip A. Prindeville ---help--- 27383197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27393197059aSPhilip A. Prindeville 27407d029125SVivien Didelotconfig TS5500 27417d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27427d029125SVivien Didelot depends on MELAN 27437d029125SVivien Didelot select CHECK_SIGNATURE 27447d029125SVivien Didelot select NEW_LEDS 27457d029125SVivien Didelot select LEDS_CLASS 27467d029125SVivien Didelot ---help--- 27477d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27487d029125SVivien Didelot 2749e279b6c1SSam Ravnborgendif # X86_32 2750e279b6c1SSam Ravnborg 275123ac4ae8SAndreas Herrmannconfig AMD_NB 2752e279b6c1SSam Ravnborg def_bool y 27530e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2754e279b6c1SSam Ravnborg 2755e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2756e279b6c1SSam Ravnborg 2757388b78adSAlexandre Bounineconfig RAPIDIO 2758fdf90abcSAlexandre Bounine tristate "RapidIO support" 2759388b78adSAlexandre Bounine depends on PCI 2760388b78adSAlexandre Bounine default n 2761388b78adSAlexandre Bounine help 2762fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2763388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2764388b78adSAlexandre Bounine 2765388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2766388b78adSAlexandre Bounine 2767e3263ab3SDavid Herrmannconfig X86_SYSFB 2768e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2769e3263ab3SDavid Herrmann help 2770e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2771e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2772e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2773e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2774e3263ab3SDavid Herrmann to x86. 2775e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2776e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2777e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2778e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2779e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2780e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2781e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2782e3263ab3SDavid Herrmann 2783e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2784e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2785e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2786e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2787e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2788e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2789e3263ab3SDavid Herrmann incompatible with simplefb. 2790e3263ab3SDavid Herrmann 2791e3263ab3SDavid Herrmann If unsure, say Y. 2792e3263ab3SDavid Herrmann 2793e279b6c1SSam Ravnborgendmenu 2794e279b6c1SSam Ravnborg 2795e279b6c1SSam Ravnborg 2796e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2797e279b6c1SSam Ravnborg 2798e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2799e279b6c1SSam Ravnborg 2800e279b6c1SSam Ravnborgconfig IA32_EMULATION 2801e279b6c1SSam Ravnborg bool "IA32 Emulation" 2802e279b6c1SSam Ravnborg depends on X86_64 280339f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2804d1603990SRandy Dunlap select BINFMT_ELF 2805a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 280639f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28078f9ca475SIngo Molnar ---help--- 28085fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28095fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28105fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2811e279b6c1SSam Ravnborg 2812e279b6c1SSam Ravnborgconfig IA32_AOUT 2813e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28146b213e1bSDavid Woodhouse depends on IA32_EMULATION 28158f9ca475SIngo Molnar ---help--- 2816e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2817e279b6c1SSam Ravnborg 28180bf62763SH. Peter Anvinconfig X86_X32 28196ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28209b54050bSBrian Gerst depends on X86_64 28215fd92e65SH. J. Lu ---help--- 28225fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28235fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28245fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28255fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28265fd92e65SH. J. Lu 28275fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 28285fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 28295fd92e65SH. J. Lu option set. 28305fd92e65SH. J. Lu 2831953fee1dSIngo Molnarconfig COMPAT_32 2832953fee1dSIngo Molnar def_bool y 2833953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2834953fee1dSIngo Molnar select HAVE_UID16 2835953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2836953fee1dSIngo Molnar 2837e279b6c1SSam Ravnborgconfig COMPAT 28383c2362e6SHarvey Harrison def_bool y 28390bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2840e279b6c1SSam Ravnborg 28413120e25eSJan Beulichif COMPAT 2842e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28433120e25eSJan Beulich def_bool y 2844e279b6c1SSam Ravnborg 2845e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28463c2362e6SHarvey Harrison def_bool y 28473120e25eSJan Beulich depends on SYSVIPC 28483120e25eSJan Beulichendif 2849ee009e4aSDavid Howells 2850e279b6c1SSam Ravnborgendmenu 2851e279b6c1SSam Ravnborg 2852e279b6c1SSam Ravnborg 2853e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2854e5beae16SKeith Packard def_bool y 2855e5beae16SKeith Packard depends on X86_32 2856e5beae16SKeith Packard 28574692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28584692d77fSAlessandro Rubini bool 285983125a3aSAlessandro Rubini depends on X86_64 || STA2X11 28604692d77fSAlessandro Rubini 2861f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2862f7219a53SAlessandro Rubini bool 286383125a3aSAlessandro Rubini depends on STA2X11 2864f7219a53SAlessandro Rubini 2865e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2866e585513bSKirill A. Shutemov def_bool y 2867e585513bSKirill A. Shutemov 2868e279b6c1SSam Ravnborgsource "net/Kconfig" 2869e279b6c1SSam Ravnborg 2870e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2871e279b6c1SSam Ravnborg 2872e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2873e279b6c1SSam Ravnborg 2874e279b6c1SSam Ravnborgsource "fs/Kconfig" 2875e279b6c1SSam Ravnborg 2876e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2877e279b6c1SSam Ravnborg 2878e279b6c1SSam Ravnborgsource "security/Kconfig" 2879e279b6c1SSam Ravnborg 2880e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2881e279b6c1SSam Ravnborg 2882edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2883edf88417SAvi Kivity 2884e279b6c1SSam Ravnborgsource "lib/Kconfig" 2885