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 95*0fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 96ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 976471b825SIngo Molnar select GENERIC_IRQ_PROBE 986471b825SIngo Molnar select GENERIC_IRQ_SHOW 996471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1006471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1016471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1026471b825SIngo Molnar select GENERIC_STRNLEN_USER 1036471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1047edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1056471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1066471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1076471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1086471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1096471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1106471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 1116471b825SIngo Molnar select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 1126471b825SIngo Molnar select HAVE_ARCH_KGDB 1136471b825SIngo Molnar select HAVE_ARCH_KMEMCHECK 1149e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1159e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1161b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1176471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 1186471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1196471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 120a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 121e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 122c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1236471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1246471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1256471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1266471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 127c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1286471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1296471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1306471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1316471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1329c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 133677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 13406aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 135c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 13658340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1375f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 138644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1396471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1406471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1416471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1426b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1430067f129SK.Prasad select HAVE_HW_BREAKPOINT 1446471b825SIngo Molnar select HAVE_IDE 1456471b825SIngo Molnar select HAVE_IOREMAP_PROT 1466471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1476471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1486471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1496471b825SIngo Molnar select HAVE_KERNEL_GZIP 1506471b825SIngo Molnar select HAVE_KERNEL_LZ4 1516471b825SIngo Molnar select HAVE_KERNEL_LZMA 1526471b825SIngo Molnar select HAVE_KERNEL_LZO 1536471b825SIngo Molnar select HAVE_KERNEL_XZ 1546471b825SIngo Molnar select HAVE_KPROBES 1556471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 1566471b825SIngo Molnar select HAVE_KRETPROBES 1576471b825SIngo Molnar select HAVE_KVM 1586471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1596471b825SIngo Molnar select HAVE_MEMBLOCK 1606471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1610102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 162ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 16342a0bb3fSPetr Mladek select HAVE_NMI 1646471b825SIngo Molnar select HAVE_OPROFILE 1656471b825SIngo Molnar select HAVE_OPTPROBES 1666471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1676471b825SIngo Molnar select HAVE_PERF_EVENTS 168c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 16992e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 170c5e63197SJiri Olsa select HAVE_PERF_REGS 171c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1729e52fc2bSVitaly Kuznetsov select HAVE_RCU_TABLE_FREE 1736471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 17481d38719SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && FRAME_POINTER_UNWINDER && STACK_VALIDATION 175c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1766471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1776471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1787c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 179c0185808SThomas Gleixner select IRQ_FORCED_THREADING 180df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1816471b825SIngo Molnar select PERF_EVENTS 1823195ef59SPrarit Bhargava select RTC_LIB 183d6faca40SArnd Bergmann select RTC_MC146818_LIB 1846471b825SIngo Molnar select SPARSE_IRQ 18583fe27eaSPranith Kumar select SRCU 1866471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 18715f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1886471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1896471b825SIngo Molnar select VIRT_TO_BUS 1906471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1917d8330a5SBalbir Singh 192ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1933120e25eSJan Beulich def_bool y 1943120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 195ba7e4d13SIngo Molnar 19651b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 19751b26adaSLinus Torvalds string 19851b26adaSLinus Torvalds default "elf32-i386" if X86_32 19951b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 20051b26adaSLinus Torvalds 20173531905SSam Ravnborgconfig ARCH_DEFCONFIG 202b9b39bfbSSam Ravnborg string 20373531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 20473531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 205b9b39bfbSSam Ravnborg 2068d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2073c2362e6SHarvey Harrison def_bool y 2088d5fffb9SSam Ravnborg 2098d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2103c2362e6SHarvey Harrison def_bool y 2118d5fffb9SSam Ravnborg 2128d5fffb9SSam Ravnborgconfig MMU 2133c2362e6SHarvey Harrison def_bool y 2148d5fffb9SSam Ravnborg 2159e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2169e08f57dSDaniel Cashman default 28 if 64BIT 2179e08f57dSDaniel Cashman default 8 2189e08f57dSDaniel Cashman 2199e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2209e08f57dSDaniel Cashman default 32 if 64BIT 2219e08f57dSDaniel Cashman default 16 2229e08f57dSDaniel Cashman 2239e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2249e08f57dSDaniel Cashman default 8 2259e08f57dSDaniel Cashman 2269e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2279e08f57dSDaniel Cashman default 16 2289e08f57dSDaniel Cashman 2298d5fffb9SSam Ravnborgconfig SBUS 2308d5fffb9SSam Ravnborg bool 2318d5fffb9SSam Ravnborg 2323bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2333120e25eSJan Beulich def_bool y 234a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2353bc4e459SFUJITA Tomonori 23618e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2374a14d84eSAndrew Morton def_bool y 23818e98307SFUJITA Tomonori 2398d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2403120e25eSJan Beulich def_bool y 2413120e25eSJan Beulich depends on ISA_DMA_API 2428d5fffb9SSam Ravnborg 2438d5fffb9SSam Ravnborgconfig GENERIC_BUG 2443c2362e6SHarvey Harrison def_bool y 2458d5fffb9SSam Ravnborg depends on BUG 246b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 247b93a531eSJan Beulich 248b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 249b93a531eSJan Beulich bool 2508d5fffb9SSam Ravnborg 2518d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2523c2362e6SHarvey Harrison def_bool y 2538d5fffb9SSam Ravnborg 2548d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2553120e25eSJan Beulich def_bool y 2563120e25eSJan Beulich depends on ISA_DMA_API 2578d5fffb9SSam Ravnborg 2581032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2593120e25eSJan Beulich def_bool y 2601032c0baSSam Ravnborg 2611032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2621032c0baSSam Ravnborg def_bool y 2631032c0baSSam Ravnborg 2649a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2659a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2668d5fffb9SSam Ravnborg 2671b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2681b27d05bSPekka Enberg def_bool y 2691b27d05bSPekka Enberg 270dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 27189c9c4c5SBrian Gerst def_bool y 272b32ef636Stravis@sgi.com 27308fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 27408fc4580STejun Heo def_bool y 27508fc4580STejun Heo 27608fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 27711124411STejun Heo def_bool y 27811124411STejun Heo 279801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 280801e4062SJohannes Berg def_bool y 281801e4062SJohannes Berg 282f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 283f4cb5700SJohannes Berg def_bool y 284f4cb5700SJohannes Berg 285cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 286cfe28c5dSSteve Capper def_bool y 287cfe28c5dSSteve Capper 28853313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 28953313b2cSSteve Capper def_bool y 29053313b2cSSteve Capper 2918d5fffb9SSam Ravnborgconfig ZONE_DMA32 292e0fd24a3SJan Beulich def_bool y if X86_64 2938d5fffb9SSam Ravnborg 2948d5fffb9SSam Ravnborgconfig AUDIT_ARCH 295e0fd24a3SJan Beulich def_bool y if X86_64 2968d5fffb9SSam Ravnborg 297765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 298765c68bdSIngo Molnar def_bool y 299765c68bdSIngo Molnar 3006a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3016a11f75bSAkinobu Mita def_bool y 3026a11f75bSAkinobu Mita 303d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 304d6f2d75aSAndrey Ryabinin hex 305d6f2d75aSAndrey Ryabinin depends on KASAN 3064c7c4483SKirill A. Shutemov default 0xdff8000000000000 if X86_5LEVEL 307d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 308d6f2d75aSAndrey Ryabinin 30969575d38SShane Wangconfig HAVE_INTEL_TXT 31069575d38SShane Wang def_bool y 3116ea30386SKees Cook depends on INTEL_IOMMU && ACPI 31269575d38SShane Wang 3136b0c3d44SSam Ravnborgconfig X86_32_SMP 3146b0c3d44SSam Ravnborg def_bool y 3156b0c3d44SSam Ravnborg depends on X86_32 && SMP 3166b0c3d44SSam Ravnborg 3176b0c3d44SSam Ravnborgconfig X86_64_SMP 3186b0c3d44SSam Ravnborg def_bool y 3196b0c3d44SSam Ravnborg depends on X86_64 && SMP 3206b0c3d44SSam Ravnborg 321ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 322ccbeed3aSTejun Heo def_bool y 32360a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 324ccbeed3aSTejun Heo 3252b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3262b144498SSrikar Dronamraju def_bool y 3272b144498SSrikar Dronamraju 328d20642f0SRob Herringconfig FIX_EARLYCON_MEM 329d20642f0SRob Herring def_bool y 330d20642f0SRob Herring 33198233368SKirill A. Shutemovconfig PGTABLE_LEVELS 33298233368SKirill A. Shutemov int 33377ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 33498233368SKirill A. Shutemov default 4 if X86_64 33598233368SKirill A. Shutemov default 3 if X86_PAE 33698233368SKirill A. Shutemov default 2 33798233368SKirill A. Shutemov 338506f1d07SSam Ravnborgsource "init/Kconfig" 339dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3408d5fffb9SSam Ravnborg 341506f1d07SSam Ravnborgmenu "Processor type and features" 342506f1d07SSam Ravnborg 3435ee71535SRandy Dunlapconfig ZONE_DMA 3445ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3455ee71535SRandy Dunlap default y 3465ee71535SRandy Dunlap help 3475ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3485ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3495ee71535SRandy Dunlap Disable if no such devices will be used. 3505ee71535SRandy Dunlap 3515ee71535SRandy Dunlap If unsure, say Y. 3525ee71535SRandy Dunlap 353506f1d07SSam Ravnborgconfig SMP 354506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 355506f1d07SSam Ravnborg ---help--- 356506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3574a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3584a474157SRobert Graffham than one CPU, say Y. 359506f1d07SSam Ravnborg 3604a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 361506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 362506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3634a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 364506f1d07SSam Ravnborg will run faster if you say N here. 365506f1d07SSam Ravnborg 366506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 367506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 368506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 369506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 370506f1d07SSam Ravnborg 371506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 372506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 373506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 374506f1d07SSam Ravnborg 375395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 376c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 377506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 378506f1d07SSam Ravnborg 379506f1d07SSam Ravnborg If you don't know what to do here, say N. 380506f1d07SSam Ravnborg 3819def39beSJosh Triplettconfig X86_FEATURE_NAMES 3829def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3839def39beSJosh Triplett default y 3849def39beSJosh Triplett ---help--- 3859def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3869def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3879def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3889def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3899def39beSJosh Triplett 3909def39beSJosh Triplett If in doubt, say Y. 3919def39beSJosh Triplett 3926e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3936e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3946e1315feSBorislav Petkov default y 3956e1315feSBorislav Petkov ---help--- 3966e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 3976e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 3986e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 3996e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 4006e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 4016e1315feSBorislav Petkov slower code. 4026e1315feSBorislav Petkov 40306cd9a7dSYinghai Luconfig X86_X2APIC 40406cd9a7dSYinghai Lu bool "Support x2apic" 40519e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 40606cd9a7dSYinghai Lu ---help--- 40706cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40806cd9a7dSYinghai Lu 40906cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 41006cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 41106cd9a7dSYinghai Lu 41206cd9a7dSYinghai Lu If you don't know what to do here, say N. 41306cd9a7dSYinghai Lu 4146695c85bSYinghai Luconfig X86_MPPARSE 4156e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4167a527688SJan Beulich default y 4175ab74722SIngo Molnar depends on X86_LOCAL_APIC 4188f9ca475SIngo Molnar ---help--- 4196695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4206695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4216695c85bSYinghai Lu 42226f7ef14SYinghai Luconfig X86_BIGSMP 42326f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 42426f7ef14SYinghai Lu depends on X86_32 && SMP 4258f9ca475SIngo Molnar ---help--- 42626f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 427506f1d07SSam Ravnborg 428ddd70cf9SJun Nakajimaconfig GOLDFISH 429ddd70cf9SJun Nakajima def_bool y 430ddd70cf9SJun Nakajima depends on X86_GOLDFISH 431ddd70cf9SJun Nakajima 432f01d7d51SVikas Shivappaconfig INTEL_RDT 433f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 43478e99b4aSFenghua Yu default n 43578e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 43659fe5a77SThomas Gleixner select KERNFS 43778e99b4aSFenghua Yu help 438f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 439f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 440f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 441f01d7d51SVikas Shivappa Architecture Software Developer Manual. 44278e99b4aSFenghua Yu 44378e99b4aSFenghua Yu Say N if unsure. 44478e99b4aSFenghua Yu 4458425091fSRavikiran G Thirumalaiif X86_32 446c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 447c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 448c5c606d9SRavikiran G Thirumalai default y 4498f9ca475SIngo Molnar ---help--- 45006ac8346SIngo Molnar If you disable this option then the kernel will only support 45106ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 45206ac8346SIngo Molnar systems out there.) 45306ac8346SIngo Molnar 4548425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4558425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 456cb7b8023SBen Hutchings Goldfish (Android emulator) 4578425091fSRavikiran G Thirumalai AMD Elan 4588425091fSRavikiran G Thirumalai RDC R-321x SoC 4598425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 46083125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4613f4110a4SThomas Gleixner Moorestown MID devices 46206ac8346SIngo Molnar 46306ac8346SIngo Molnar If you have one of these systems, or if you want to build a 46406ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4658425091fSRavikiran G Thirumalaiendif 46606ac8346SIngo Molnar 4678425091fSRavikiran G Thirumalaiif X86_64 4688425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4698425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4708425091fSRavikiran G Thirumalai default y 4718425091fSRavikiran G Thirumalai ---help--- 4728425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4738425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4748425091fSRavikiran G Thirumalai systems out there.) 4758425091fSRavikiran G Thirumalai 4768425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4778425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 47844b111b5SSteffen Persvold Numascale NumaChip 4798425091fSRavikiran G Thirumalai ScaleMP vSMP 4808425091fSRavikiran G Thirumalai SGI Ultraviolet 4818425091fSRavikiran G Thirumalai 4828425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4838425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4848425091fSRavikiran G Thirumalaiendif 485c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 486c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 48744b111b5SSteffen Persvoldconfig X86_NUMACHIP 48844b111b5SSteffen Persvold bool "Numascale NumaChip" 48944b111b5SSteffen Persvold depends on X86_64 49044b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 49144b111b5SSteffen Persvold depends on NUMA 49244b111b5SSteffen Persvold depends on SMP 49344b111b5SSteffen Persvold depends on X86_X2APIC 494f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 49544b111b5SSteffen Persvold ---help--- 49644b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 49744b111b5SSteffen Persvold enable more than ~168 cores. 49844b111b5SSteffen Persvold If you don't have one of these, you should say N here. 49903b48632SNick Piggin 5006a48565eSIngo Molnarconfig X86_VSMP 501c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5026276a074SBorislav Petkov select HYPERVISOR_GUEST 5036a48565eSIngo Molnar select PARAVIRT 5046a48565eSIngo Molnar depends on X86_64 && PCI 505c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 506ead91d4bSShai Fultheim depends on SMP 5078f9ca475SIngo Molnar ---help--- 5086a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5096a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5106a48565eSIngo Molnar if you have one of these machines. 5116a48565eSIngo Molnar 512c5c606d9SRavikiran G Thirumalaiconfig X86_UV 513c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 514c5c606d9SRavikiran G Thirumalai depends on X86_64 515c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 51654c28d29SJack Steiner depends on NUMA 5171ecb4ae5SAndrew Morton depends on EFI 5189d6c26e7SSuresh Siddha depends on X86_X2APIC 5191222e564SIngo Molnar depends on PCI 520c5c606d9SRavikiran G Thirumalai ---help--- 521c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 522c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 523c5c606d9SRavikiran G Thirumalai 524c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 525c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 526506f1d07SSam Ravnborg 527ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 528ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 529cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 530ddd70cf9SJun Nakajima ---help--- 531ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 532ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 533ddd70cf9SJun Nakajima Goldfish emulator say N here. 534ddd70cf9SJun Nakajima 535c751e17bSThomas Gleixnerconfig X86_INTEL_CE 536c751e17bSThomas Gleixner bool "CE4100 TV platform" 537c751e17bSThomas Gleixner depends on PCI 538c751e17bSThomas Gleixner depends on PCI_GODIRECT 5396084a6e2SJiang Liu depends on X86_IO_APIC 540c751e17bSThomas Gleixner depends on X86_32 541c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 54237bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 543da6b737bSSebastian Andrzej Siewior select OF 544da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 545c751e17bSThomas Gleixner ---help--- 546c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 547c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 548c751e17bSThomas Gleixner boxes and media devices. 549c751e17bSThomas Gleixner 5504cb9b00fSDavid Cohenconfig X86_INTEL_MID 55143605ef1SAlan Cox bool "Intel MID platform support" 55243605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 553edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5541ea7c673SAlan Cox depends on PCI 5553fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5561ea7c673SAlan Cox depends on X86_IO_APIC 5577c9c3a1eSAlan Cox select SFI 5584cb9b00fSDavid Cohen select I2C 5597c9c3a1eSAlan Cox select DW_APB_TIMER 5601ea7c673SAlan Cox select APB_TIMER 5611ea7c673SAlan Cox select INTEL_SCU_IPC 56215a713dfSMika Westerberg select MFD_INTEL_MSIC 5631ea7c673SAlan Cox ---help--- 5644cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5654cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5664cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5671ea7c673SAlan Cox 5684cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5694cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 57043605ef1SAlan Cox 5718bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5728bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5738bbc2a13SBryan O'Donoghue depends on X86_32 5748bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5758bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5768bbc2a13SBryan O'Donoghue depends on X86_TSC 5778bbc2a13SBryan O'Donoghue depends on PCI 5788bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5798bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5808bbc2a13SBryan O'Donoghue select IOSF_MBI 5818bbc2a13SBryan O'Donoghue select INTEL_IMR 5829ab6eb51SAndy Shevchenko select COMMON_CLK 5838bbc2a13SBryan O'Donoghue ---help--- 5848bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5858bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5868bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5878bbc2a13SBryan O'Donoghue 5883d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5893d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 590eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5913d48aab1SMika Westerberg select COMMON_CLK 5920f531431SMathias Nyman select PINCTRL 593eebb3e8dSAndy Shevchenko select IOSF_MBI 5943d48aab1SMika Westerberg ---help--- 5953d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 5963d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 5970f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 5980f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 5993d48aab1SMika Westerberg 60092082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 60192082a88SKen Xue bool "AMD ACPI2Platform devices support" 60292082a88SKen Xue depends on ACPI 60392082a88SKen Xue select COMMON_CLK 60492082a88SKen Xue select PINCTRL 60592082a88SKen Xue ---help--- 60692082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 60792082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 60892082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 60992082a88SKen Xue implemented under PINCTRL subsystem. 61092082a88SKen Xue 611ced3ce76SDavid E. Boxconfig IOSF_MBI 612ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 613ced3ce76SDavid E. Box depends on PCI 614ced3ce76SDavid E. Box ---help--- 615ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 616ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 617ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 618ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 619ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 620ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 621ced3ce76SDavid E. Box This list is not meant to be exclusive. 622ced3ce76SDavid E. Box - BayTrail 623ced3ce76SDavid E. Box - Braswell 624ced3ce76SDavid E. Box - Quark 625ced3ce76SDavid E. Box 626ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 627ced3ce76SDavid E. Box 628ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 629ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 630ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 631ed2226bdSDavid E. Box ---help--- 632ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 633ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 634ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 635ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 636ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 637ed2226bdSDavid E. Box device they want to access. 638ed2226bdSDavid E. Box 639ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 640ed2226bdSDavid E. Box 641c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 642c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 643506f1d07SSam Ravnborg depends on X86_32 644c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 645c5c606d9SRavikiran G Thirumalai select M486 646c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 647c5c606d9SRavikiran G Thirumalai ---help--- 648c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 649c5c606d9SRavikiran G Thirumalai as R-8610-(G). 650c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 651c5c606d9SRavikiran G Thirumalai 652e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6539c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6549c398017SIngo Molnar depends on X86_32 && SMP 655c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6568f9ca475SIngo Molnar ---help--- 657b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 658b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 659b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 660b5660ba7SH. Peter Anvin one and will fallback to default. 661d49c4288SYinghai Lu 662c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 663d49c4288SYinghai Lu 664d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6656fc108a0SJan Beulich def_bool y 666d949f36fSLinus Torvalds # MCE code calls memory_failure(): 667d949f36fSLinus Torvalds depends on X86_MCE 668d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 669d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 670d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 671d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 672d949f36fSLinus Torvalds 67383125a3aSAlessandro Rubiniconfig STA2X11 67483125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 67583125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 67683125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 67783125a3aSAlessandro Rubini select X86_DMA_REMAP 67883125a3aSAlessandro Rubini select SWIOTLB 67983125a3aSAlessandro Rubini select MFD_STA2X11 6800145071bSLinus Walleij select GPIOLIB 68183125a3aSAlessandro Rubini default n 68283125a3aSAlessandro Rubini ---help--- 68383125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 68483125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 68583125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 68683125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 68783125a3aSAlessandro Rubini standard PC machines. 68883125a3aSAlessandro Rubini 68982148d1dSShérabconfig X86_32_IRIS 69082148d1dSShérab tristate "Eurobraille/Iris poweroff module" 69182148d1dSShérab depends on X86_32 69282148d1dSShérab ---help--- 69382148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 69482148d1dSShérab to shut themselves down properly. A special I/O sequence is 69582148d1dSShérab needed to do so, which is what this module does at 69682148d1dSShérab kernel shutdown. 69782148d1dSShérab 69882148d1dSShérab This is only for Iris machines from EuroBraille. 69982148d1dSShérab 70082148d1dSShérab If unused, say N. 70182148d1dSShérab 702ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7033c2362e6SHarvey Harrison def_bool y 7043c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 705a87d0914SKen Chen depends on X86 7068f9ca475SIngo Molnar ---help--- 707506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 708506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 709506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 710506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 711506f1d07SSam Ravnborg 712506f1d07SSam Ravnborg If in doubt, say "Y". 713506f1d07SSam Ravnborg 7146276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7156276a074SBorislav Petkov bool "Linux guest support" 7168f9ca475SIngo Molnar ---help--- 7176276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7186276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7196276a074SBorislav Petkov setup. 720506f1d07SSam Ravnborg 7216276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7226276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 723506f1d07SSam Ravnborg 7246276a074SBorislav Petkovif HYPERVISOR_GUEST 725506f1d07SSam Ravnborg 726e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 727e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7288f9ca475SIngo Molnar ---help--- 729e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 730e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 731e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 732e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 733e61bd94aSEduardo Pereira Habkost 7346276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7356276a074SBorislav Petkov bool "paravirt-ops debugging" 7366276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7376276a074SBorislav Petkov ---help--- 7386276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7396276a074SBorislav Petkov a paravirt_op is missing when it is called. 7406276a074SBorislav Petkov 741b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 742b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7436ea30386SKees Cook depends on PARAVIRT && SMP 744b4ecc126SJeremy Fitzhardinge ---help--- 745b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 746b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 747b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 748b4ecc126SJeremy Fitzhardinge 7494c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7504c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 751b4ecc126SJeremy Fitzhardinge 7524c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 753b4ecc126SJeremy Fitzhardinge 75445e898b7SWaiman Longconfig QUEUED_LOCK_STAT 75545e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 756cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 75745e898b7SWaiman Long ---help--- 75845e898b7SWaiman Long Enable the collection of statistical data on the slowpath 75945e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 76045e898b7SWaiman Long them on debugfs. 76145e898b7SWaiman Long 7626276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7636276a074SBorislav Petkov 7646276a074SBorislav Petkovconfig KVM_GUEST 7656276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7666276a074SBorislav Petkov depends on PARAVIRT 7676276a074SBorislav Petkov select PARAVIRT_CLOCK 7686276a074SBorislav Petkov default y 7696276a074SBorislav Petkov ---help--- 7706276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7716276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7726276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7736276a074SBorislav Petkov underlying device model, the host provides the guest with 7746276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7756276a074SBorislav Petkov 7761e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7771e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7781e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7791e20eb85SSrivatsa Vaddagiri default n 7801e20eb85SSrivatsa Vaddagiri ---help--- 7811e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7821e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7831e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7841e20eb85SSrivatsa Vaddagiri 7856276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7866276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7876276a074SBorislav Petkov depends on PARAVIRT 7886276a074SBorislav Petkov default n 7896276a074SBorislav Petkov ---help--- 7906276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7916276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7926276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 7936276a074SBorislav Petkov that, there can be a small performance impact. 7946276a074SBorislav Petkov 7956276a074SBorislav Petkov If in doubt, say N here. 7966276a074SBorislav Petkov 7977af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 7987af192c9SGerd Hoffmann bool 7997af192c9SGerd Hoffmann 8006276a074SBorislav Petkovendif #HYPERVISOR_GUEST 80197349135SJeremy Fitzhardinge 80208677214SYinghai Luconfig NO_BOOTMEM 803774ea0bcSYinghai Lu def_bool y 80408677214SYinghai Lu 805506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 806506f1d07SSam Ravnborg 807506f1d07SSam Ravnborgconfig HPET_TIMER 8083c2362e6SHarvey Harrison def_bool X86_64 809506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8108f9ca475SIngo Molnar ---help--- 811506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 812506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 813506f1d07SSam Ravnborg present. 814506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 815506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 816506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8174e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8184e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 819506f1d07SSam Ravnborg 820506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 821506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 822506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 823506f1d07SSam Ravnborg 824506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 825506f1d07SSam Ravnborg 826506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8273c2362e6SHarvey Harrison def_bool y 8289d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 829506f1d07SSam Ravnborg 830bb24c471SJacob Panconfig APB_TIMER 831933b9463SAlan Cox def_bool y if X86_INTEL_MID 832933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 83306c3df49SJamie Iles select DW_APB_TIMER 834a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 835bb24c471SJacob Pan help 836bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 837bb24c471SJacob Pan The APBT provides a stable time base on SMP 838bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 839bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 840bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 841bb24c471SJacob Pan 8426a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 843506f1d07SSam Ravnborg# The code disables itself when not needed. 8447ae9392cSThomas Petazzoniconfig DMI 8457ae9392cSThomas Petazzoni default y 846cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8476a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8488f9ca475SIngo Molnar ---help--- 8497ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8507ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8517ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8527ae9392cSThomas Petazzoni BIOS code. 8537ae9392cSThomas Petazzoni 854506f1d07SSam Ravnborgconfig GART_IOMMU 85538901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 856506f1d07SSam Ravnborg select SWIOTLB 85723ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8588f9ca475SIngo Molnar ---help--- 859ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 860ced3c42cSIngo Molnar GART based hardware IOMMUs. 861ced3c42cSIngo Molnar 862ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 863ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 864ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 865ced3c42cSIngo Molnar 866ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 867ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 868ced3c42cSIngo Molnar 869ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 870ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 871ced3c42cSIngo Molnar 32-bit limited device. 872ced3c42cSIngo Molnar 873ced3c42cSIngo Molnar If unsure, say Y. 874506f1d07SSam Ravnborg 875506f1d07SSam Ravnborgconfig CALGARY_IOMMU 876506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 877506f1d07SSam Ravnborg select SWIOTLB 8786ea30386SKees Cook depends on X86_64 && PCI 8798f9ca475SIngo Molnar ---help--- 880506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 881506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 882506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 883506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 884506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 885506f1d07SSam Ravnborg prevents them from going anywhere except their intended 886506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 887506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 888506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 889506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 890506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 891506f1d07SSam Ravnborg If unsure, say Y. 892506f1d07SSam Ravnborg 893506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 8943c2362e6SHarvey Harrison def_bool y 8953c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 896506f1d07SSam Ravnborg depends on CALGARY_IOMMU 8978f9ca475SIngo Molnar ---help--- 898506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 899506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 900506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 901506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 902506f1d07SSam Ravnborg If unsure, say Y. 903506f1d07SSam Ravnborg 904506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 905506f1d07SSam Ravnborgconfig SWIOTLB 906a1afd01cSJoerg Roedel def_bool y if X86_64 9078f9ca475SIngo Molnar ---help--- 908506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9094454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9104454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9114454d327SJoe Millenbach with more than 3 GB of memory. 9124454d327SJoe Millenbach If unsure, say Y. 913506f1d07SSam Ravnborg 914a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9153120e25eSJan Beulich def_bool y 9163120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 917d25e26b6SLinus Torvalds 9181184dc2fSMike Travisconfig MAXSMP 919ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9206ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 92136f5101aSMike Travis select CPUMASK_OFFSTACK 9228f9ca475SIngo Molnar ---help--- 923ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9241184dc2fSMike Travis If unsure, say N. 925506f1d07SSam Ravnborg 926506f1d07SSam Ravnborgconfig NR_CPUS 92736f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 9282a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 929bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 930b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 93178637a97SMike Travis default "1" if !SMP 932b53b5edaSJosh Boyer default "8192" if MAXSMP 933b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 934c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 935c5c19941SKirill A. Shutemov default "64" if SMP 9368f9ca475SIngo Molnar ---help--- 937506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 938bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 939cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 940506f1d07SSam Ravnborg minimum value which makes sense is 2. 941506f1d07SSam Ravnborg 942506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 943506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 944506f1d07SSam Ravnborg 945506f1d07SSam Ravnborgconfig SCHED_SMT 946506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 947c8e56d20SBorislav Petkov depends on SMP 9488f9ca475SIngo Molnar ---help--- 949506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 950506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 951506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 952506f1d07SSam Ravnborg N here. 953506f1d07SSam Ravnborg 954506f1d07SSam Ravnborgconfig SCHED_MC 9553c2362e6SHarvey Harrison def_bool y 9563c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 957c8e56d20SBorislav Petkov depends on SMP 9588f9ca475SIngo Molnar ---help--- 959506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 960506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 961506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 962506f1d07SSam Ravnborg 963de966cf4STim Chenconfig SCHED_MC_PRIO 964de966cf4STim Chen bool "CPU core priorities scheduler support" 9650a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 9660a21fc12SIngo Molnar select X86_INTEL_PSTATE 9670a21fc12SIngo Molnar select CPU_FREQ 968de966cf4STim Chen default y 9695e76b2abSTim Chen ---help--- 970de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 971de966cf4STim Chen core ordering determined at manufacturing time, which allows 972de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 973de966cf4STim Chen single threaded workloads) than others. 974de966cf4STim Chen 975de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 976de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 977de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 978de966cf4STim Chen overall system performance can be achieved. 979de966cf4STim Chen 980de966cf4STim Chen This feature will have no effect on CPUs without this feature. 981de966cf4STim Chen 982de966cf4STim Chen If unsure say Y here. 9835e76b2abSTim Chen 984506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 985506f1d07SSam Ravnborg 98630b8b006SThomas Gleixnerconfig UP_LATE_INIT 98730b8b006SThomas Gleixner def_bool y 988ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 98930b8b006SThomas Gleixner 990506f1d07SSam Ravnborgconfig X86_UP_APIC 99150849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 99250849eefSJan Beulich default PCI_MSI 99338a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 9948f9ca475SIngo Molnar ---help--- 995506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 996506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 997506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 998506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 999506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1000506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1001506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1002506f1d07SSam Ravnborg lockups. 1003506f1d07SSam Ravnborg 1004506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1005506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1006506f1d07SSam Ravnborg depends on X86_UP_APIC 10078f9ca475SIngo Molnar ---help--- 1008506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1009506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1010506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1011506f1d07SSam Ravnborg 1012506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1013506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1014506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1015506f1d07SSam Ravnborg 1016506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10173c2362e6SHarvey Harrison def_bool y 10180dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1019b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 102052f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1021506f1d07SSam Ravnborg 1022506f1d07SSam Ravnborgconfig X86_IO_APIC 1023b1da1e71SJan Beulich def_bool y 1024b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1025506f1d07SSam Ravnborg 102641b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 102741b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 102841b9eb26SStefan Assmann depends on X86_IO_APIC 10298f9ca475SIngo Molnar ---help--- 103041b9eb26SStefan Assmann This option enables a workaround that fixes a source of 103141b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 103241b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 103341b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 103441b9eb26SStefan Assmann 103541b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 103641b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 103741b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 103841b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 103941b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 104041b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 104141b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 104241b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 104341b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 104441b9eb26SStefan Assmann down (vital) interrupt lines. 104541b9eb26SStefan Assmann 104641b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 104741b9eb26SStefan Assmann increased on these systems. 104841b9eb26SStefan Assmann 1049506f1d07SSam Ravnborgconfig X86_MCE 1050bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1051648ed940SChen, Gong select GENERIC_ALLOCATOR 1052e57dbaf7SBorislav Petkov default y 1053506f1d07SSam Ravnborg ---help--- 1054bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1055bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1056506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1057bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10584efc0670SAndi Kleen 10595de97c9fSTony Luckconfig X86_MCELOG_LEGACY 10605de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 10615de97c9fSTony Luck depends on X86_MCE 10625de97c9fSTony Luck ---help--- 10635de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 10645de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 10655de97c9fSTony Luck rasdaemon solution. 10665de97c9fSTony Luck 1067506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10683c2362e6SHarvey Harrison def_bool y 10693c2362e6SHarvey Harrison prompt "Intel MCE features" 1070c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10718f9ca475SIngo Molnar ---help--- 1072506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1073506f1d07SSam Ravnborg the thermal monitor. 1074506f1d07SSam Ravnborg 1075506f1d07SSam Ravnborgconfig X86_MCE_AMD 10763c2362e6SHarvey Harrison def_bool y 10773c2362e6SHarvey Harrison prompt "AMD MCE features" 1078f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 10798f9ca475SIngo Molnar ---help--- 1080506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1081506f1d07SSam Ravnborg the DRAM Error Threshold. 1082506f1d07SSam Ravnborg 10834efc0670SAndi Kleenconfig X86_ANCIENT_MCE 10846fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1085c31d9633SAndi Kleen depends on X86_32 && X86_MCE 10864efc0670SAndi Kleen ---help--- 10874efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 10885065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 10894efc0670SAndi Kleen line. 10904efc0670SAndi Kleen 1091b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1092b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 10936fc108a0SJan Beulich def_bool y 1094b2762686SAndi Kleen 1095ea149b36SAndi Kleenconfig X86_MCE_INJECT 1096bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1097ea149b36SAndi Kleen tristate "Machine check injector support" 1098ea149b36SAndi Kleen ---help--- 1099ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1100ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1101ea149b36SAndi Kleen QA it is safe to say n. 1102ea149b36SAndi Kleen 11034efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11044efc0670SAndi Kleen def_bool y 11055bb38adcSAndi Kleen depends on X86_MCE_INTEL 11064efc0670SAndi Kleen 110707dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1108e633c65aSKan Liang 11095aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11101e642812SIngo Molnar bool "Legacy VM86 support" 11115aef51c3SAndy Lutomirski default n 1112506f1d07SSam Ravnborg depends on X86_32 11138f9ca475SIngo Molnar ---help--- 11145aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11155aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11165aef51c3SAndy Lutomirski 11175aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11185aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11195aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11205aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11215aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11221e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11231e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11241e642812SIngo Molnar mode might be faster than emulation and you might want to 11251e642812SIngo Molnar enable this option. 11265aef51c3SAndy Lutomirski 11271e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11281e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11291e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11301e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11315aef51c3SAndy Lutomirski 11321e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11331e642812SIngo Molnar and slows down exception handling a tiny bit. 11345aef51c3SAndy Lutomirski 11351e642812SIngo Molnar If unsure, say N here. 11365aef51c3SAndy Lutomirski 11375aef51c3SAndy Lutomirskiconfig VM86 11385aef51c3SAndy Lutomirski bool 11395aef51c3SAndy Lutomirski default X86_LEGACY_VM86 114034273f41SH. Peter Anvin 114134273f41SH. Peter Anvinconfig X86_16BIT 114234273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 114334273f41SH. Peter Anvin default y 1144a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 114534273f41SH. Peter Anvin ---help--- 114634273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 114734273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 114834273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 114934273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 115034273f41SH. Peter Anvin 115134273f41SH. Peter Anvinconfig X86_ESPFIX32 115234273f41SH. Peter Anvin def_bool y 115334273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1154506f1d07SSam Ravnborg 1155197725deSH. Peter Anvinconfig X86_ESPFIX64 1156197725deSH. Peter Anvin def_bool y 115734273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1158506f1d07SSam Ravnborg 11591ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 11601ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 11611ad83c85SAndy Lutomirski default y 11621ad83c85SAndy Lutomirski depends on X86_64 11631ad83c85SAndy Lutomirski ---help--- 11641ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 11651ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 11661ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11671ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11681ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11691ad83c85SAndy Lutomirski 0xffffffffff600?00. 11701ad83c85SAndy Lutomirski 11711ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 11721ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 11731ad83c85SAndy Lutomirski 11741ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 11751ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 11761ad83c85SAndy Lutomirski 1177506f1d07SSam Ravnborgconfig TOSHIBA 1178506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1179506f1d07SSam Ravnborg depends on X86_32 1180506f1d07SSam Ravnborg ---help--- 1181506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1182506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1183506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1184506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1185506f1d07SSam Ravnborg 1186506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1187506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1188506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1189506f1d07SSam Ravnborg 1190506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1191506f1d07SSam Ravnborg Say N otherwise. 1192506f1d07SSam Ravnborg 1193506f1d07SSam Ravnborgconfig I8K 1194039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1195949a9d70SJean Delvare select HWMON 1196039ae585SPali Rohár select SENSORS_DELL_SMM 1197506f1d07SSam Ravnborg ---help--- 1198039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1199039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1200039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1201039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1202039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1203039ae585SPali Rohár needed userspace package i8kutils. 1204506f1d07SSam Ravnborg 1205039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1206039ae585SPali Rohár use userspace package i8kutils. 1207506f1d07SSam Ravnborg Say N otherwise. 1208506f1d07SSam Ravnborg 1209506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12109ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12119ba16087SJan Beulich depends on X86_32 1212506f1d07SSam Ravnborg ---help--- 1213506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1214506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1215506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1216506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1217506f1d07SSam Ravnborg system. 1218506f1d07SSam Ravnborg 1219506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12205e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1221506f1d07SSam Ravnborg 1222506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1223506f1d07SSam Ravnborg enable this option even if you don't need it. 1224506f1d07SSam Ravnborg Say N otherwise. 1225506f1d07SSam Ravnborg 1226506f1d07SSam Ravnborgconfig MICROCODE 12279a2bc335SBorislav Petkov bool "CPU microcode loading support" 12289a2bc335SBorislav Petkov default y 122980030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1230506f1d07SSam Ravnborg select FW_LOADER 1231506f1d07SSam Ravnborg ---help--- 1232506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12335f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12345f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12355f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12365f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12375f9c01aaSBorislav Petkov the Linux kernel. 1238506f1d07SSam Ravnborg 12395f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12405f9c01aaSBorislav Petkov in Documentation/x86/early-microcode.txt. For that you need to enable 12415f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12425f9c01aaSBorislav Petkov initrd for microcode blobs. 1243506f1d07SSam Ravnborg 12445f9c01aaSBorislav Petkov In addition, you can build-in the microcode into the kernel. For that you 12455f9c01aaSBorislav Petkov need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 12465f9c01aaSBorislav Petkov to the CONFIG_EXTRA_FIRMWARE config option. 1247506f1d07SSam Ravnborg 12488d86f390SPeter Orubaconfig MICROCODE_INTEL 1249e43f6e67SBorislav Petkov bool "Intel microcode loading support" 12508d86f390SPeter Oruba depends on MICROCODE 12518d86f390SPeter Oruba default MICROCODE 12528d86f390SPeter Oruba select FW_LOADER 12538f9ca475SIngo Molnar ---help--- 12548d86f390SPeter Oruba This options enables microcode patch loading support for Intel 12558d86f390SPeter Oruba processors. 12568d86f390SPeter Oruba 1257b8989db9SAlan For the current Intel microcode data package go to 1258b8989db9SAlan <https://downloadcenter.intel.com> and search for 1259b8989db9SAlan 'Linux Processor Microcode Data File'. 12608d86f390SPeter Oruba 126180cc9f10SPeter Orubaconfig MICROCODE_AMD 1262e43f6e67SBorislav Petkov bool "AMD microcode loading support" 126380cc9f10SPeter Oruba depends on MICROCODE 126480cc9f10SPeter Oruba select FW_LOADER 12658f9ca475SIngo Molnar ---help--- 126680cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 126780cc9f10SPeter Oruba processors will be enabled. 126880cc9f10SPeter Oruba 1269506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12703c2362e6SHarvey Harrison def_bool y 1271506f1d07SSam Ravnborg depends on MICROCODE 1272506f1d07SSam Ravnborg 1273506f1d07SSam Ravnborgconfig X86_MSR 1274506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 12758f9ca475SIngo Molnar ---help--- 1276506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1277506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1278506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1279506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1280506f1d07SSam Ravnborg systems. 1281506f1d07SSam Ravnborg 1282506f1d07SSam Ravnborgconfig X86_CPUID 1283506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 12848f9ca475SIngo Molnar ---help--- 1285506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1286506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1287506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1288506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1289506f1d07SSam Ravnborg 1290506f1d07SSam Ravnborgchoice 1291506f1d07SSam Ravnborg prompt "High Memory Support" 12926fc108a0SJan Beulich default HIGHMEM4G 1293506f1d07SSam Ravnborg depends on X86_32 1294506f1d07SSam Ravnborg 1295506f1d07SSam Ravnborgconfig NOHIGHMEM 1296506f1d07SSam Ravnborg bool "off" 1297506f1d07SSam Ravnborg ---help--- 1298506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1299506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1300506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1301506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1302506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1303506f1d07SSam Ravnborg "high memory". 1304506f1d07SSam Ravnborg 1305506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1306506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1307506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1308506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1309506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1310506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1311506f1d07SSam Ravnborg possible. 1312506f1d07SSam Ravnborg 1313506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1314506f1d07SSam Ravnborg answer "4GB" here. 1315506f1d07SSam Ravnborg 1316506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1317506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1318506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1319506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1320506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1321506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1322506f1d07SSam Ravnborg 1323506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1324506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1325506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1326506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1327506f1d07SSam Ravnborg kernel at boot time.) 1328506f1d07SSam Ravnborg 1329506f1d07SSam Ravnborg If unsure, say "off". 1330506f1d07SSam Ravnborg 1331506f1d07SSam Ravnborgconfig HIGHMEM4G 1332506f1d07SSam Ravnborg bool "4GB" 13338f9ca475SIngo Molnar ---help--- 1334506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1335506f1d07SSam Ravnborg gigabytes of physical RAM. 1336506f1d07SSam Ravnborg 1337506f1d07SSam Ravnborgconfig HIGHMEM64G 1338506f1d07SSam Ravnborg bool "64GB" 1339eb068e78SH. Peter Anvin depends on !M486 1340506f1d07SSam Ravnborg select X86_PAE 13418f9ca475SIngo Molnar ---help--- 1342506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1343506f1d07SSam Ravnborg gigabytes of physical RAM. 1344506f1d07SSam Ravnborg 1345506f1d07SSam Ravnborgendchoice 1346506f1d07SSam Ravnborg 1347506f1d07SSam Ravnborgchoice 13486a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1349506f1d07SSam Ravnborg default VMSPLIT_3G 1350506f1d07SSam Ravnborg depends on X86_32 13518f9ca475SIngo Molnar ---help--- 1352506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1353506f1d07SSam Ravnborg 1354506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1355506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1356506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1357506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1358506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1359506f1d07SSam Ravnborg available to user programs, making the address space there 1360506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1361506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1362506f1d07SSam Ravnborg kernel modules. 1363506f1d07SSam Ravnborg 1364506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1365506f1d07SSam Ravnborg option alone! 1366506f1d07SSam Ravnborg 1367506f1d07SSam Ravnborg config VMSPLIT_3G 1368506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1369506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1370506f1d07SSam Ravnborg depends on !X86_PAE 1371506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1372506f1d07SSam Ravnborg config VMSPLIT_2G 1373506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1374506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1375506f1d07SSam Ravnborg depends on !X86_PAE 1376506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1377506f1d07SSam Ravnborg config VMSPLIT_1G 1378506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1379506f1d07SSam Ravnborgendchoice 1380506f1d07SSam Ravnborg 1381506f1d07SSam Ravnborgconfig PAGE_OFFSET 1382506f1d07SSam Ravnborg hex 1383506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1384506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1385506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1386506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1387506f1d07SSam Ravnborg default 0xC0000000 1388506f1d07SSam Ravnborg depends on X86_32 1389506f1d07SSam Ravnborg 1390506f1d07SSam Ravnborgconfig HIGHMEM 13913c2362e6SHarvey Harrison def_bool y 1392506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1393506f1d07SSam Ravnborg 1394506f1d07SSam Ravnborgconfig X86_PAE 13959ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1396506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 13979d99c712SChristian Melki select SWIOTLB 13988f9ca475SIngo Molnar ---help--- 1399506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1400506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1401506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1402506f1d07SSam Ravnborg consumes more pagetable space per process. 1403506f1d07SSam Ravnborg 140477ef56e4SKirill A. Shutemovconfig X86_5LEVEL 140577ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 140677ef56e4SKirill A. Shutemov depends on X86_64 140777ef56e4SKirill A. Shutemov ---help--- 140877ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 140977ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 141077ef56e4SKirill A. Shutemov physical address space. 141177ef56e4SKirill A. Shutemov 141277ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 141377ef56e4SKirill A. Shutemov 141477ef56e4SKirill A. Shutemov Note: a kernel with this option enabled can only be booted 141577ef56e4SKirill A. Shutemov on machines that support the feature. 141677ef56e4SKirill A. Shutemov 141777ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 141877ef56e4SKirill A. Shutemov information. 141977ef56e4SKirill A. Shutemov 142077ef56e4SKirill A. Shutemov Say N if unsure. 142177ef56e4SKirill A. Shutemov 1422600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14233120e25eSJan Beulich def_bool y 14243120e25eSJan Beulich depends on X86_64 || X86_PAE 1425600715dcSJeremy Fitzhardinge 142666f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14273120e25eSJan Beulich def_bool y 14283120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 142966f2b061SFUJITA Tomonori 143010971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1431e5008abeSLuis R. Rodriguez def_bool y 1432e5008abeSLuis R. Rodriguez depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 14338f9ca475SIngo Molnar ---help--- 143410971ab2SIngo Molnar Certain kernel features effectively disable kernel 143510971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 143610971ab2SIngo Molnar supports them), so don't confuse the user by printing 143710971ab2SIngo Molnar that we have them enabled. 14389e899816SNick Piggin 14397744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 14407744ccdbSTom Lendacky def_bool y 14417744ccdbSTom Lendacky 14427744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 14437744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 14447744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 14457744ccdbSTom Lendacky ---help--- 14467744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 14477744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 14487744ccdbSTom Lendacky Encryption (SME). 14497744ccdbSTom Lendacky 14507744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 14517744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 14527744ccdbSTom Lendacky default y 14537744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 14547744ccdbSTom Lendacky ---help--- 14557744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 14567744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 14577744ccdbSTom Lendacky 14587744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 14597744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 14607744ccdbSTom Lendacky 14617744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 14627744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 14637744ccdbSTom Lendacky 1464f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1465f88a68faSTom Lendacky def_bool y 1466f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1467f88a68faSTom Lendacky 1468506f1d07SSam Ravnborg# Common NUMA Features 1469506f1d07SSam Ravnborgconfig NUMA 1470fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1471506f1d07SSam Ravnborg depends on SMP 1472b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1473b5660ba7SH. Peter Anvin default y if X86_BIGSMP 14748f9ca475SIngo Molnar ---help--- 1475506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1476fd51b2d7SKOSAKI Motohiro 1477506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1478506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1479506f1d07SSam Ravnborg NUMA awareness to the kernel. 1480506f1d07SSam Ravnborg 1481c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1482fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1483fd51b2d7SKOSAKI Motohiro 1484b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 14857cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1486fd51b2d7SKOSAKI Motohiro 1487fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1488506f1d07SSam Ravnborg 1489eec1d4faSHans Rosenfeldconfig AMD_NUMA 14903c2362e6SHarvey Harrison def_bool y 14913c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 14925da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 14938f9ca475SIngo Molnar ---help--- 1494eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1495eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1496eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1497eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1498eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1499506f1d07SSam Ravnborg 1500506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15013c2362e6SHarvey Harrison def_bool y 15023c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1503506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1504506f1d07SSam Ravnborg select ACPI_NUMA 15058f9ca475SIngo Molnar ---help--- 1506506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1507506f1d07SSam Ravnborg 15086ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15096ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15106ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15116ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15126ec6e0d9SSuresh Siddha# for details. 15136ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15146ec6e0d9SSuresh Siddha def_bool y 15156ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15166ec6e0d9SSuresh Siddha 1517506f1d07SSam Ravnborgconfig NUMA_EMU 1518506f1d07SSam Ravnborg bool "NUMA emulation" 15191b7e03efSTejun Heo depends on NUMA 15208f9ca475SIngo Molnar ---help--- 1521506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1522506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1523506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1524506f1d07SSam Ravnborg 1525506f1d07SSam Ravnborgconfig NODES_SHIFT 1526d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 152751591e31SDavid Rientjes range 1 10 152851591e31SDavid Rientjes default "10" if MAXSMP 1529506f1d07SSam Ravnborg default "6" if X86_64 1530506f1d07SSam Ravnborg default "3" 1531506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15328f9ca475SIngo Molnar ---help--- 15331184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1534692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1535506f1d07SSam Ravnborg 1536506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15373c2362e6SHarvey Harrison def_bool y 1538506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1539506f1d07SSam Ravnborg 1540506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 15413c2362e6SHarvey Harrison def_bool y 1542506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1543506f1d07SSam Ravnborg 1544506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1545506f1d07SSam Ravnborg def_bool y 15463b16651fSTejun Heo depends on X86_32 && !NUMA 1547506f1d07SSam Ravnborg 1548506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1549506f1d07SSam Ravnborg def_bool y 1550b263295dSChristoph Lameter depends on NUMA && X86_32 1551506f1d07SSam Ravnborg 1552506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1553506f1d07SSam Ravnborg def_bool y 1554b263295dSChristoph Lameter depends on NUMA && X86_32 1555b263295dSChristoph Lameter 1556506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1557506f1d07SSam Ravnborg def_bool y 15586ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1559506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1560506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1561506f1d07SSam Ravnborg 15623b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 15633b16651fSTejun Heo def_bool y 15643b16651fSTejun Heo depends on X86_64 15653b16651fSTejun Heo 1566506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1567506f1d07SSam Ravnborg def_bool y 1568b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1569506f1d07SSam Ravnborg 1570506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1571a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 15723120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1573a0842b70SToshi Kani help 1574a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1575a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1576a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1577506f1d07SSam Ravnborg 15783b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 15793b16651fSTejun Heo def_bool y 15803b16651fSTejun Heo depends on X86_64 && PROC_KCORE 15813b16651fSTejun Heo 1582a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1583a29815a3SAvi Kivity hex 1584a29815a3SAvi Kivity default 0 if X86_32 1585a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1586a29815a3SAvi Kivity 1587506f1d07SSam Ravnborgsource "mm/Kconfig" 1588506f1d07SSam Ravnborg 15897a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 15907a67832cSDan Williams bool 15917a67832cSDan Williams 1592ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 15937a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 15949f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 15959f53f9faSDan Williams depends on BLK_DEV 15967a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 15979f53f9faSDan Williams select LIBNVDIMM 1598ec776ef6SChristoph Hellwig help 1599ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1600ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1601ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1602ec776ef6SChristoph Hellwig they can be used for persistent storage. 1603ec776ef6SChristoph Hellwig 1604ec776ef6SChristoph Hellwig Say Y if unsure. 1605ec776ef6SChristoph Hellwig 1606506f1d07SSam Ravnborgconfig HIGHPTE 1607506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16086fc108a0SJan Beulich depends on HIGHMEM 16098f9ca475SIngo Molnar ---help--- 1610506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1611506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1612506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1613506f1d07SSam Ravnborg entries in high memory. 1614506f1d07SSam Ravnborg 16159f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16169f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16178f9ca475SIngo Molnar ---help--- 16189f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16199f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16209f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16219f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16229f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16239f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16249f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16258c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16269f077871SJeremy Fitzhardinge 16279f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16289f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16299f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16309f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16319f077871SJeremy Fitzhardinge 16329f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16339f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16349f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16359f077871SJeremy Fitzhardinge memory. 16369f077871SJeremy Fitzhardinge 1637c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1638c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1639c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1640c885df50SJeremy Fitzhardinge default y 16418f9ca475SIngo Molnar ---help--- 1642c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1643c885df50SJeremy Fitzhardinge on or off. 1644c885df50SJeremy Fitzhardinge 16459ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1646d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1647d0cd7425SH. Peter Anvin default 64 1648d0cd7425SH. Peter Anvin range 4 640 16498f9ca475SIngo Molnar ---help--- 1650d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1651fc381519SIngo Molnar 1652d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1653d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1654fc381519SIngo Molnar 1655d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1656d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1657d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1658d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1659fc381519SIngo Molnar 1660d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1661d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1662d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1663d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1664d0cd7425SH. Peter Anvin entire low memory range. 1665d0cd7425SH. Peter Anvin 1666d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1667d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1668d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1669d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1670d0cd7425SH. Peter Anvin typical corruption patterns. 1671d0cd7425SH. Peter Anvin 1672d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1673fc381519SIngo Molnar 1674506f1d07SSam Ravnborgconfig MATH_EMULATION 1675506f1d07SSam Ravnborg bool 1676a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1677506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1678506f1d07SSam Ravnborg ---help--- 1679506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1680506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1681506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1682506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1683506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1684506f1d07SSam Ravnborg coprocessor or this emulation. 1685506f1d07SSam Ravnborg 1686506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1687506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1688506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1689506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1690506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1691506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1692506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1693506f1d07SSam Ravnborg intend to use this kernel on different machines. 1694506f1d07SSam Ravnborg 1695506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1696506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1697506f1d07SSam Ravnborg 1698506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1699506f1d07SSam Ravnborg kernel, it won't hurt. 1700506f1d07SSam Ravnborg 1701506f1d07SSam Ravnborgconfig MTRR 17026fc108a0SJan Beulich def_bool y 17036a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1704506f1d07SSam Ravnborg ---help--- 1705506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1706506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1707506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1708506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1709506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1710506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1711506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1712506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1713506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1714506f1d07SSam Ravnborg 1715506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1716506f1d07SSam Ravnborg control registers on other processors can be easily supported 1717506f1d07SSam Ravnborg as well: 1718506f1d07SSam Ravnborg 1719506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1720506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1721506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1722506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1723506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1724506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1725506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1726506f1d07SSam Ravnborg 1727506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1728506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1729506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1730506f1d07SSam Ravnborg 1731506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1732506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1733506f1d07SSam Ravnborg 17347225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1735506f1d07SSam Ravnborg 173695ffa243SYinghai Luconfig MTRR_SANITIZER 17372ffb3501SYinghai Lu def_bool y 173895ffa243SYinghai Lu prompt "MTRR cleanup support" 173995ffa243SYinghai Lu depends on MTRR 17408f9ca475SIngo Molnar ---help--- 1741aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1742aba3728cSThomas Gleixner add writeback entries. 174395ffa243SYinghai Lu 1744aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1745692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1746aba3728cSThomas Gleixner mtrr_chunk_size. 174795ffa243SYinghai Lu 17482ffb3501SYinghai Lu If unsure, say Y. 174995ffa243SYinghai Lu 175095ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1751f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1752f5098d62SYinghai Lu range 0 1 1753f5098d62SYinghai Lu default "0" 175495ffa243SYinghai Lu depends on MTRR_SANITIZER 17558f9ca475SIngo Molnar ---help--- 1756f5098d62SYinghai Lu Enable mtrr cleanup default value 175795ffa243SYinghai Lu 175812031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 175912031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 176012031a62SYinghai Lu range 0 7 176112031a62SYinghai Lu default "1" 176212031a62SYinghai Lu depends on MTRR_SANITIZER 17638f9ca475SIngo Molnar ---help--- 176412031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1765aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 176612031a62SYinghai Lu 17672e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 17686fc108a0SJan Beulich def_bool y 17696a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 17702a8a2719SIngo Molnar depends on MTRR 17718f9ca475SIngo Molnar ---help--- 17722e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1773042b78e4SVenki Pallipadi 17742e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 17752e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 17762e5d9c85Svenkatesh.pallipadi@intel.com 17772e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1778042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 17792e5d9c85Svenkatesh.pallipadi@intel.com 17802e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 17812e5d9c85Svenkatesh.pallipadi@intel.com 178246cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 178346cf98cdSVenkatesh Pallipadi def_bool y 178446cf98cdSVenkatesh Pallipadi depends on X86_PAT 178546cf98cdSVenkatesh Pallipadi 1786628c6246SH. Peter Anvinconfig ARCH_RANDOM 1787628c6246SH. Peter Anvin def_bool y 1788628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1789628c6246SH. Peter Anvin ---help--- 1790628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1791628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1792628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1793628c6246SH. Peter Anvin secure hardware random number generator. 1794628c6246SH. Peter Anvin 179551ae4a2dSH. Peter Anvinconfig X86_SMAP 179651ae4a2dSH. Peter Anvin def_bool y 179751ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 179851ae4a2dSH. Peter Anvin ---help--- 179951ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 180051ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 180151ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 180251ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 180351ae4a2dSH. Peter Anvin 180451ae4a2dSH. Peter Anvin If unsure, say Y. 180551ae4a2dSH. Peter Anvin 180672e9b5feSDave Hansenconfig X86_INTEL_MPX 180772e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 180872e9b5feSDave Hansen def_bool n 1809df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1810df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1811df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 181272e9b5feSDave Hansen ---help--- 181372e9b5feSDave Hansen MPX provides hardware features that can be used in 181472e9b5feSDave Hansen conjunction with compiler-instrumented code to check 181572e9b5feSDave Hansen memory references. It is designed to detect buffer 181672e9b5feSDave Hansen overflow or underflow bugs. 181772e9b5feSDave Hansen 181872e9b5feSDave Hansen This option enables running applications which are 181972e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 182072e9b5feSDave Hansen itself inside the kernel or to protect the kernel 182172e9b5feSDave Hansen against bad memory references. 182272e9b5feSDave Hansen 182372e9b5feSDave Hansen Enabling this option will make the kernel larger: 182472e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 182572e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 182672e9b5feSDave Hansen will increase the kernel memory overhead of each 182772e9b5feSDave Hansen process and adds some branches to paths used during 182872e9b5feSDave Hansen exec() and munmap(). 182972e9b5feSDave Hansen 183072e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 183172e9b5feSDave Hansen 183272e9b5feSDave Hansen If unsure, say N. 183372e9b5feSDave Hansen 183435e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1835284244a9SDave Hansen prompt "Intel Memory Protection Keys" 183635e97790SDave Hansen def_bool y 1837284244a9SDave Hansen # Note: only available in 64-bit mode 183835e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 183952c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 184052c8e601SIngo Molnar select ARCH_HAS_PKEYS 1841284244a9SDave Hansen ---help--- 1842284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1843284244a9SDave Hansen page-based protections, but without requiring modification of the 1844284244a9SDave Hansen page tables when an application changes protection domains. 1845284244a9SDave Hansen 1846284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1847284244a9SDave Hansen 1848284244a9SDave Hansen If unsure, say y. 184935e97790SDave Hansen 1850506f1d07SSam Ravnborgconfig EFI 18519ba16087SJan Beulich bool "EFI runtime service support" 18525b83683fSHuang, Ying depends on ACPI 1853f6ce5002SSergey Vlasov select UCS2_STRING 1854022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1855506f1d07SSam Ravnborg ---help--- 18568b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1857506f1d07SSam Ravnborg available (such as the EFI variable services). 1858506f1d07SSam Ravnborg 18598b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 18608b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 18618b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 18628b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 18638b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 18648b2cb7a8SHuang, Ying platforms. 1865506f1d07SSam Ravnborg 1866291f3632SMatt Flemingconfig EFI_STUB 1867291f3632SMatt Fleming bool "EFI stub support" 1868b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 18697b2a583aSMatt Fleming select RELOCATABLE 1870291f3632SMatt Fleming ---help--- 1871291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1872291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1873291f3632SMatt Fleming 18744172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 18750c759662SMatt Fleming 18767d453eeeSMatt Flemingconfig EFI_MIXED 18777d453eeeSMatt Fleming bool "EFI mixed-mode support" 18787d453eeeSMatt Fleming depends on EFI_STUB && X86_64 18797d453eeeSMatt Fleming ---help--- 18807d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 18817d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 18827d453eeeSMatt Fleming mode. 18837d453eeeSMatt Fleming 18847d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 18857d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 18867d453eeeSMatt Fleming the EFI handover protocol must be used. 18877d453eeeSMatt Fleming 18887d453eeeSMatt Fleming If unsure, say N. 18897d453eeeSMatt Fleming 1890506f1d07SSam Ravnborgconfig SECCOMP 18913c2362e6SHarvey Harrison def_bool y 18923c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 18938f9ca475SIngo Molnar ---help--- 1894506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1895506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1896506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1897506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1898506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1899506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19009c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1901506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1902506f1d07SSam Ravnborg defined by each seccomp mode. 1903506f1d07SSam Ravnborg 1904506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1905506f1d07SSam Ravnborg 1906506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1907506f1d07SSam Ravnborg 1908506f1d07SSam Ravnborgconfig KEXEC 1909506f1d07SSam Ravnborg bool "kexec system call" 19102965faa5SDave Young select KEXEC_CORE 19118f9ca475SIngo Molnar ---help--- 1912506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1913506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1914506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1915506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1916506f1d07SSam Ravnborg 1917506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1918506f1d07SSam Ravnborg 1919506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1920506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1921bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1922bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1923bf220695SGeert Uytterhoeven made. 1924506f1d07SSam Ravnborg 192574ca317cSVivek Goyalconfig KEXEC_FILE 192674ca317cSVivek Goyal bool "kexec file based system call" 19272965faa5SDave Young select KEXEC_CORE 192874ca317cSVivek Goyal select BUILD_BIN2C 192974ca317cSVivek Goyal depends on X86_64 193074ca317cSVivek Goyal depends on CRYPTO=y 193174ca317cSVivek Goyal depends on CRYPTO_SHA256=y 193274ca317cSVivek Goyal ---help--- 193374ca317cSVivek Goyal This is new version of kexec system call. This system call is 193474ca317cSVivek Goyal file based and takes file descriptors as system call argument 193574ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 193674ca317cSVivek Goyal accepted by previous system call. 193774ca317cSVivek Goyal 19388e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 19398e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 194074ca317cSVivek Goyal depends on KEXEC_FILE 19418e7d8381SVivek Goyal ---help--- 19428e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1943d8eb8940SBorislav Petkov the kexec_file_load() syscall. 19448e7d8381SVivek Goyal 1945d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1946d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1947d8eb8940SBorislav Petkov loaded in order for this to work. 19488e7d8381SVivek Goyal 19498e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 19508e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 19518e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 19528e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 19538e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 19548e7d8381SVivek Goyal ---help--- 19558e7d8381SVivek Goyal Enable bzImage signature verification support. 19568e7d8381SVivek Goyal 1957506f1d07SSam Ravnborgconfig CRASH_DUMP 195804b69447SPavel Machek bool "kernel crash dumps" 1959506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 19608f9ca475SIngo Molnar ---help--- 1961506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1962506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1963506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1964506f1d07SSam Ravnborg a specially reserved region and then later executed after 1965506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1966506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1967506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1968506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1969506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1970506f1d07SSam Ravnborg 19713ab83521SHuang Yingconfig KEXEC_JUMP 19726ea30386SKees Cook bool "kexec jump" 1973fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 19748f9ca475SIngo Molnar ---help--- 197589081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 197689081d17SHuang Ying code in physical address mode via KEXEC 19773ab83521SHuang Ying 1978506f1d07SSam Ravnborgconfig PHYSICAL_START 19796a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1980ceefccc9SH. Peter Anvin default "0x1000000" 19818f9ca475SIngo Molnar ---help--- 1982506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1983506f1d07SSam Ravnborg 1984506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1985506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1986506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1987506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1988506f1d07SSam Ravnborg address. 1989506f1d07SSam Ravnborg 1990506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1991506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1992506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1993506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1994506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1995506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1996506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1997506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1998506f1d07SSam Ravnborg 1999ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2000ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2001ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2002ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2003ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2004ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2005ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2006ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2007ceefccc9SH. Peter Anvin for more details about crash dumps. 2008506f1d07SSam Ravnborg 2009506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2010506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2011506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2012506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2013506f1d07SSam Ravnborg is present because there are users out there who continue to use 2014506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2015506f1d07SSam Ravnborg line. 2016506f1d07SSam Ravnborg 2017506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2018506f1d07SSam Ravnborg 2019506f1d07SSam Ravnborgconfig RELOCATABLE 202026717808SH. Peter Anvin bool "Build a relocatable kernel" 202126717808SH. Peter Anvin default y 20228f9ca475SIngo Molnar ---help--- 2023506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2024506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2025506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2026506f1d07SSam Ravnborg but are discarded at runtime. 2027506f1d07SSam Ravnborg 2028506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2029506f1d07SSam Ravnborg must live at a different physical address than the primary 2030506f1d07SSam Ravnborg kernel. 2031506f1d07SSam Ravnborg 2032506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2033506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 20348ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2035506f1d07SSam Ravnborg 20368ab3820fSKees Cookconfig RANDOMIZE_BASE 2037e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 20388ab3820fSKees Cook depends on RELOCATABLE 20396807c846SIngo Molnar default y 20408ab3820fSKees Cook ---help--- 2041e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2042e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2043e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2044e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2045e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2046e8581e3dSBaoquan He code internals. 2047e8581e3dSBaoquan He 2048ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2049ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2050ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2051ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2052ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2053ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2054ed9f007eSKees Cook 2055ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2056ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2057ed9f007eSKees Cook 512MB (8 bits of entropy). 20588ab3820fSKees Cook 2059a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2060e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2061e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2062ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2063ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2064ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2065ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2066ed9f007eSKees Cook theoretically possible, but the implementations are further 2067ed9f007eSKees Cook limited due to memory layouts. 2068e8581e3dSBaoquan He 20696807c846SIngo Molnar If unsure, say Y. 2070da2b6fb9SKees Cook 20718ab3820fSKees Cook# Relocation on x86 needs some additional build support 2072845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2073845adf72SH. Peter Anvin def_bool y 20748ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2075845adf72SH. Peter Anvin 2076506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2077a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 20788ab3820fSKees Cook default "0x200000" 2079a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2080a0215061SKees Cook range 0x200000 0x1000000 if X86_64 20818f9ca475SIngo Molnar ---help--- 2082506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2083506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2084506f1d07SSam Ravnborg address which meets above alignment restriction. 2085506f1d07SSam Ravnborg 2086506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2087506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2088506f1d07SSam Ravnborg address aligned to above value and run from there. 2089506f1d07SSam Ravnborg 2090506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2091506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2092506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2093506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2094506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2095506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2096506f1d07SSam Ravnborg above alignment restrictions. 2097506f1d07SSam Ravnborg 2098a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2099a0215061SKees Cook this value must be a multiple of 0x200000. 2100a0215061SKees Cook 2101506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2102506f1d07SSam Ravnborg 21030483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21040483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21050483e1faSThomas Garnier depends on X86_64 21060483e1faSThomas Garnier depends on RANDOMIZE_BASE 21070483e1faSThomas Garnier default RANDOMIZE_BASE 21080483e1faSThomas Garnier ---help--- 21090483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21100483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21110483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21120483e1faSThomas Garnier 21130483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21140483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21150483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21160483e1faSThomas Garnier addresses for each memory section. 21170483e1faSThomas Garnier 21186807c846SIngo Molnar If unsure, say Y. 21190483e1faSThomas Garnier 212090397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 212190397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 212290397a41SThomas Garnier depends on RANDOMIZE_MEMORY 212390397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 212490397a41SThomas Garnier default "0x0" 212590397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 212690397a41SThomas Garnier range 0x0 0x40 212790397a41SThomas Garnier ---help--- 212890397a41SThomas Garnier Define the padding in terabytes added to the existing physical 212990397a41SThomas Garnier memory size during kernel memory randomization. It is useful 213090397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 213190397a41SThomas Garnier address randomization. 213290397a41SThomas Garnier 213390397a41SThomas Garnier If unsure, leave at the default value. 213490397a41SThomas Garnier 2135506f1d07SSam Ravnborgconfig HOTPLUG_CPU 21367c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 213740b31360SStephen Rothwell depends on SMP 2138506f1d07SSam Ravnborg ---help--- 21397c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 21407c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 21417c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 21427c13e6a3SDimitri Sivanich automatically on SMP systems. ) 21437c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2144506f1d07SSam Ravnborg 214580aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 214680aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 214780aa1dffSFenghua Yu default n 21482c922cd0SKees Cook depends on HOTPLUG_CPU 214980aa1dffSFenghua Yu ---help--- 215080aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 215180aa1dffSFenghua Yu 215280aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 215380aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 215480aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 215580aa1dffSFenghua Yu 215680aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 215780aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 215880aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 215980aa1dffSFenghua Yu 216080aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 216180aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 216280aa1dffSFenghua Yu 216380aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 216480aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 216580aa1dffSFenghua Yu be other CPU0 dependencies. 216680aa1dffSFenghua Yu 216780aa1dffSFenghua Yu Please make sure the dependencies are under your control before 216880aa1dffSFenghua Yu you enable this feature. 216980aa1dffSFenghua Yu 217080aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 217180aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 217280aa1dffSFenghua Yu parameter cpu0_hotplug. 217380aa1dffSFenghua Yu 2174a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2175a71c8bc5SFenghua Yu def_bool n 2176a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 21772c922cd0SKees Cook depends on HOTPLUG_CPU 2178a71c8bc5SFenghua Yu ---help--- 2179a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2180a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2181a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2182a71c8bc5SFenghua Yu 2183a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2184a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2185a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2186a71c8bc5SFenghua Yu 2187a71c8bc5SFenghua Yu If unsure, say N. 2188a71c8bc5SFenghua Yu 2189506f1d07SSam Ravnborgconfig COMPAT_VDSO 2190b0b49f26SAndy Lutomirski def_bool n 2191b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2192953fee1dSIngo Molnar depends on COMPAT_32 21938f9ca475SIngo Molnar ---help--- 2194b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2195b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2196b0b49f26SAndy Lutomirski indicated in its segment table. 2197e84446deSRandy Dunlap 2198b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2199b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2200b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2201b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2202b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2203506f1d07SSam Ravnborg 2204b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2205b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2206b0b49f26SAndy Lutomirski 2207b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2208b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2209b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2210b0b49f26SAndy Lutomirski 2211b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2212b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2213506f1d07SSam Ravnborg 22143dc33bd3SKees Cookchoice 22153dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22163dc33bd3SKees Cook depends on X86_64 22173dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 22183dc33bd3SKees Cook help 22193dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 22203dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 22213dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 22223dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22233dc33bd3SKees Cook 22243dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 22253dc33bd3SKees Cook line parameter vsyscall=[native|emulate|none]. 22263dc33bd3SKees Cook 22273dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22283dc33bd3SKees Cook static binaries, you can say None without a performance penalty 22293dc33bd3SKees Cook to improve security. 22303dc33bd3SKees Cook 22313dc33bd3SKees Cook If unsure, select "Emulate". 22323dc33bd3SKees Cook 22333dc33bd3SKees Cook config LEGACY_VSYSCALL_NATIVE 22343dc33bd3SKees Cook bool "Native" 22353dc33bd3SKees Cook help 22363dc33bd3SKees Cook Actual executable code is located in the fixed vsyscall 22373dc33bd3SKees Cook address mapping, implementing time() efficiently. Since 22383dc33bd3SKees Cook this makes the mapping executable, it can be used during 22393dc33bd3SKees Cook security vulnerability exploitation (traditionally as 22403dc33bd3SKees Cook ROP gadgets). This configuration is not recommended. 22413dc33bd3SKees Cook 22423dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 22433dc33bd3SKees Cook bool "Emulate" 22443dc33bd3SKees Cook help 22453dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 22463dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 22473dc33bd3SKees Cook non-executable, but it still contains known contents, 22483dc33bd3SKees Cook which could be used in certain rare security vulnerability 22493dc33bd3SKees Cook exploits. This configuration is recommended when userspace 22503dc33bd3SKees Cook still uses the vsyscall area. 22513dc33bd3SKees Cook 22523dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 22533dc33bd3SKees Cook bool "None" 22543dc33bd3SKees Cook help 22553dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 22563dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 22573dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 22583dc33bd3SKees Cook will be reported to dmesg, so that either old or 22593dc33bd3SKees Cook malicious userspace programs can be identified. 22603dc33bd3SKees Cook 22613dc33bd3SKees Cookendchoice 22623dc33bd3SKees Cook 2263516cbf37STim Birdconfig CMDLINE_BOOL 2264516cbf37STim Bird bool "Built-in kernel command line" 22658f9ca475SIngo Molnar ---help--- 2266516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2267516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2268516cbf37STim Bird necessary or convenient to provide some or all of the 2269516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2270516cbf37STim Bird to not rely on the boot loader to provide them.) 2271516cbf37STim Bird 2272516cbf37STim Bird To compile command line arguments into the kernel, 2273516cbf37STim Bird set this option to 'Y', then fill in the 227469711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2275516cbf37STim Bird 2276516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2277516cbf37STim Bird should leave this option set to 'N'. 2278516cbf37STim Bird 2279516cbf37STim Birdconfig CMDLINE 2280516cbf37STim Bird string "Built-in kernel command string" 2281516cbf37STim Bird depends on CMDLINE_BOOL 2282516cbf37STim Bird default "" 22838f9ca475SIngo Molnar ---help--- 2284516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2285516cbf37STim Bird image and used at boot time. If the boot loader provides a 2286516cbf37STim Bird command line at boot time, it is appended to this string to 2287516cbf37STim Bird form the full kernel command line, when the system boots. 2288516cbf37STim Bird 2289516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2290516cbf37STim Bird change this behavior. 2291516cbf37STim Bird 2292516cbf37STim Bird In most cases, the command line (whether built-in or provided 2293516cbf37STim Bird by the boot loader) should specify the device for the root 2294516cbf37STim Bird file system. 2295516cbf37STim Bird 2296516cbf37STim Birdconfig CMDLINE_OVERRIDE 2297516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2298516cbf37STim Bird depends on CMDLINE_BOOL 22998f9ca475SIngo Molnar ---help--- 2300516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2301516cbf37STim Bird command line, and use ONLY the built-in command line. 2302516cbf37STim Bird 2303516cbf37STim Bird This is used to work around broken boot loaders. This should 2304516cbf37STim Bird be set to 'N' under normal conditions. 2305516cbf37STim Bird 2306a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2307a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2308a5b9e5a2SAndy Lutomirski default y 2309a5b9e5a2SAndy Lutomirski ---help--- 2310a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2311a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2312a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2313a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2314a5b9e5a2SAndy Lutomirski threading libraries. 2315a5b9e5a2SAndy Lutomirski 2316a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2317a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2318a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2319a5b9e5a2SAndy Lutomirski 2320a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2321a5b9e5a2SAndy Lutomirski 2322b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2323b700e7f0SSeth Jennings 2324506f1d07SSam Ravnborgendmenu 2325506f1d07SSam Ravnborg 23263072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 23273072e413SMichal Hocko def_bool y 23283072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 23293072e413SMichal Hocko 2330506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2331506f1d07SSam Ravnborg def_bool y 2332506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2333506f1d07SSam Ravnborg 233435551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 233535551053SGary Hade def_bool y 233635551053SGary Hade depends on MEMORY_HOTPLUG 233735551053SGary Hade 2338e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2339645a7919STejun Heo def_bool y 2340e534c7c5SLee Schermerhorn depends on NUMA 2341e534c7c5SLee Schermerhorn 23429491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 23439491846fSKirill A. Shutemov def_bool y 23449491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 23459491846fSKirill A. Shutemov 2346c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2347c177c81eSNaoya Horiguchi def_bool y 2348c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2349c177c81eSNaoya Horiguchi 23509c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 23519c670ea3SNaoya Horiguchi def_bool y 23529c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 23539c670ea3SNaoya Horiguchi 2354da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2355e279b6c1SSam Ravnborg 2356e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 23573c2362e6SHarvey Harrison def_bool y 2358e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2359e279b6c1SSam Ravnborg 2360e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2361e279b6c1SSam Ravnborg 2362e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2363e279b6c1SSam Ravnborg 2364efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2365efafc8b2SFeng Tang 2366a6b68076SAndi Kleenconfig X86_APM_BOOT 23676fc108a0SJan Beulich def_bool y 2368282e5aabSPaul Bolle depends on APM 2369a6b68076SAndi Kleen 2370e279b6c1SSam Ravnborgmenuconfig APM 2371e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2372efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2373e279b6c1SSam Ravnborg ---help--- 2374e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2375e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2376e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2377e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2378e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2379e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2380e279b6c1SSam Ravnborg 2381e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2382e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2383e279b6c1SSam Ravnborg 2384e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2385e279b6c1SSam Ravnborg machines with more than one CPU. 2386e279b6c1SSam Ravnborg 2387e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 23882dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 23892dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2390e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2391e279b6c1SSam Ravnborg 2392e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2393e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2394e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2395e279b6c1SSam Ravnborg 2396e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2397e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2398e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2399e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2400e279b6c1SSam Ravnborg 2401e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2402e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2403e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2404e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2405e279b6c1SSam Ravnborg APM in your BIOS). 2406e279b6c1SSam Ravnborg 2407e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2408e279b6c1SSam Ravnborg "weird" problems: 2409e279b6c1SSam Ravnborg 2410e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2411e279b6c1SSam Ravnborg enabled. 2412e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2413e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2414e279b6c1SSam Ravnborg the "no387" option to the kernel 2415e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2416e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2417e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2418e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2419e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2420e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2421e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2422e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2423e279b6c1SSam Ravnborg 11) exchange RAM chips 2424e279b6c1SSam Ravnborg 12) exchange the motherboard. 2425e279b6c1SSam Ravnborg 2426e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2427e279b6c1SSam Ravnborg module will be called apm. 2428e279b6c1SSam Ravnborg 2429e279b6c1SSam Ravnborgif APM 2430e279b6c1SSam Ravnborg 2431e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2432e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 24338f9ca475SIngo Molnar ---help--- 2434e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2435e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2436e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2437e279b6c1SSam Ravnborg 2438e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2439e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2440e279b6c1SSam Ravnborg ---help--- 2441e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2442e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2443e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2444e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2445e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2446e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2447e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2448e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2449e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2450e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2451e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2452e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2453e279b6c1SSam Ravnborg this feature. 2454e279b6c1SSam Ravnborg 2455e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2456dd8af076SLen Brown depends on CPU_IDLE 2457e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 24588f9ca475SIngo Molnar ---help--- 2459e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2460e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2461e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2462e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2463e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2464e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2465e279b6c1SSam Ravnborg this option does nothing.) 2466e279b6c1SSam Ravnborg 2467e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2468e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 24698f9ca475SIngo Molnar ---help--- 2470e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2471e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2472e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2473e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2474e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2475e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2476e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2477e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2478e279b6c1SSam Ravnborg especially if you are using gpm. 2479e279b6c1SSam Ravnborg 2480e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2481e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 24828f9ca475SIngo Molnar ---help--- 2483e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2484e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2485e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2486e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2487e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2488e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2489e279b6c1SSam Ravnborg 2490e279b6c1SSam Ravnborgendif # APM 2491e279b6c1SSam Ravnborg 2492bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2493e279b6c1SSam Ravnborg 2494e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2495e279b6c1SSam Ravnborg 249627471fdbSAndy Henroidsource "drivers/idle/Kconfig" 249727471fdbSAndy Henroid 2498e279b6c1SSam Ravnborgendmenu 2499e279b6c1SSam Ravnborg 2500e279b6c1SSam Ravnborg 2501e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2502e279b6c1SSam Ravnborg 2503e279b6c1SSam Ravnborgconfig PCI 25041ac97018SIngo Molnar bool "PCI support" 25051c858087SAdrian Bunk default y 25068f9ca475SIngo Molnar ---help--- 2507e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2508e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2509e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2510e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2511e279b6c1SSam Ravnborg 2512e279b6c1SSam Ravnborgchoice 2513e279b6c1SSam Ravnborg prompt "PCI access mode" 2514efefa6f6SIngo Molnar depends on X86_32 && PCI 2515e279b6c1SSam Ravnborg default PCI_GOANY 2516e279b6c1SSam Ravnborg ---help--- 2517e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2518e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2519e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2520e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2521e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2522e279b6c1SSam Ravnborg 2523e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2524e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2525e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2526e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2527e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2528e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2529e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2530e279b6c1SSam Ravnborg 2531e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2532e279b6c1SSam Ravnborg bool "BIOS" 2533e279b6c1SSam Ravnborg 2534e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2535e279b6c1SSam Ravnborg bool "MMConfig" 2536e279b6c1SSam Ravnborg 2537e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2538e279b6c1SSam Ravnborg bool "Direct" 2539e279b6c1SSam Ravnborg 25403ef0e1f8SAndres Salomonconfig PCI_GOOLPC 254176fb6570SDaniel Drake bool "OLPC XO-1" 25423ef0e1f8SAndres Salomon depends on OLPC 25433ef0e1f8SAndres Salomon 25442bdd1b03SAndres Salomonconfig PCI_GOANY 25452bdd1b03SAndres Salomon bool "Any" 25462bdd1b03SAndres Salomon 2547e279b6c1SSam Ravnborgendchoice 2548e279b6c1SSam Ravnborg 2549e279b6c1SSam Ravnborgconfig PCI_BIOS 25503c2362e6SHarvey Harrison def_bool y 2551efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2552e279b6c1SSam Ravnborg 2553e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2554e279b6c1SSam Ravnborgconfig PCI_DIRECT 25553c2362e6SHarvey Harrison def_bool y 25560aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2557e279b6c1SSam Ravnborg 2558e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 25593c2362e6SHarvey Harrison def_bool y 25605f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2561e279b6c1SSam Ravnborg 25623ef0e1f8SAndres Salomonconfig PCI_OLPC 25632bdd1b03SAndres Salomon def_bool y 25642bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 25653ef0e1f8SAndres Salomon 2566b5401a96SAlex Nixonconfig PCI_XEN 2567b5401a96SAlex Nixon def_bool y 2568b5401a96SAlex Nixon depends on PCI && XEN 2569b5401a96SAlex Nixon select SWIOTLB_XEN 2570b5401a96SAlex Nixon 2571e279b6c1SSam Ravnborgconfig PCI_DOMAINS 25723c2362e6SHarvey Harrison def_bool y 2573e279b6c1SSam Ravnborg depends on PCI 2574e279b6c1SSam Ravnborg 2575e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2576e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2577e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2578e279b6c1SSam Ravnborg 25793f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 25806a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 25816ea30386SKees Cook depends on PCI 25823f6ea84aSIra W. Snyder help 25833f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 25843f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 25853f6ea84aSIra W. Snyder not have ACPI. 25863f6ea84aSIra W. Snyder 258764a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 258864a5fed6SBjorn Helgaas is known to be incomplete. 258964a5fed6SBjorn Helgaas 259064a5fed6SBjorn Helgaas You should say N unless you know you need this. 259164a5fed6SBjorn Helgaas 2592e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2593e279b6c1SSam Ravnborg 25943a495511SWilliam Breathitt Grayconfig ISA_BUS 25953a495511SWilliam Breathitt Gray bool "ISA-style bus support on modern systems" if EXPERT 25963a495511SWilliam Breathitt Gray select ISA_BUS_API 25973a495511SWilliam Breathitt Gray help 25983a495511SWilliam Breathitt Gray Enables ISA-style drivers on modern systems. This is necessary to 25993a495511SWilliam Breathitt Gray support PC/104 devices on X86_64 platforms. 26003a495511SWilliam Breathitt Gray 26013a495511SWilliam Breathitt Gray If unsure, say N. 26023a495511SWilliam Breathitt Gray 26031c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2604e279b6c1SSam Ravnborgconfig ISA_DMA_API 26051c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26061c00f016SDavid Rientjes default y 26071c00f016SDavid Rientjes help 26081c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26091c00f016SDavid Rientjes If unsure, say Y. 2610e279b6c1SSam Ravnborg 261151e68d05SLinus Torvaldsif X86_32 261251e68d05SLinus Torvalds 2613e279b6c1SSam Ravnborgconfig ISA 2614e279b6c1SSam Ravnborg bool "ISA support" 26158f9ca475SIngo Molnar ---help--- 2616e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2617e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2618e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2619e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2620e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2621e279b6c1SSam Ravnborg 2622e279b6c1SSam Ravnborgconfig EISA 2623e279b6c1SSam Ravnborg bool "EISA support" 2624e279b6c1SSam Ravnborg depends on ISA 2625e279b6c1SSam Ravnborg ---help--- 2626e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2627e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2628e279b6c1SSam Ravnborg 2629e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2630e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2631e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2632e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2633e279b6c1SSam Ravnborg 2634e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2635e279b6c1SSam Ravnborg 2636e279b6c1SSam Ravnborg Otherwise, say N. 2637e279b6c1SSam Ravnborg 2638e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2639e279b6c1SSam Ravnborg 2640e279b6c1SSam Ravnborgconfig SCx200 2641e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26428f9ca475SIngo Molnar ---help--- 2643e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2644e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2645e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2646e279b6c1SSam Ravnborg for other scx200_* drivers. 2647e279b6c1SSam Ravnborg 2648e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2649e279b6c1SSam Ravnborg 2650e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2651e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2652592913ecSJohn Stultz depends on SCx200 2653e279b6c1SSam Ravnborg default y 26548f9ca475SIngo Molnar ---help--- 2655e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2656e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2657e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2658e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2659e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2660e279b6c1SSam Ravnborg 26613ef0e1f8SAndres Salomonconfig OLPC 26623ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 266354008979SThomas Gleixner depends on !X86_PAE 26643c554946SAndres Salomon select GPIOLIB 2665dc3119e7SThomas Gleixner select OF 266645bb1674SDaniel Drake select OF_PROMTREE 2667b4e51854SGrant Likely select IRQ_DOMAIN 26688f9ca475SIngo Molnar ---help--- 26693ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 26703ef0e1f8SAndres Salomon XO hardware. 26713ef0e1f8SAndres Salomon 2672a3128588SDaniel Drakeconfig OLPC_XO1_PM 2673a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 267497c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2675a3128588SDaniel Drake select MFD_CORE 2676bf1ebf00SDaniel Drake ---help--- 267797c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2678bf1ebf00SDaniel Drake 2679cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2680cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2681cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2682cfee9597SDaniel Drake ---help--- 2683cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2684cfee9597SDaniel Drake programmable wakeup source. 2685cfee9597SDaniel Drake 26867feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 26877feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2688d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2689ed8e47feSRandy Dunlap depends on INPUT=y 2690d8d01a63SDaniel Drake select POWER_SUPPLY 26917feda8e9SDaniel Drake select GPIO_CS5535 26927feda8e9SDaniel Drake select MFD_CORE 26937feda8e9SDaniel Drake ---help--- 26947feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 26957bc74b3dSDaniel Drake - EC-driven system wakeups 26967feda8e9SDaniel Drake - Power button 26977bc74b3dSDaniel Drake - Ebook switch 26982cf2baeaSDaniel Drake - Lid switch 2699e1040ac6SDaniel Drake - AC adapter status updates 2700e1040ac6SDaniel Drake - Battery status updates 27017feda8e9SDaniel Drake 2702a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2703a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2704d8d01a63SDaniel Drake depends on OLPC && ACPI 2705d8d01a63SDaniel Drake select POWER_SUPPLY 2706a0f30f59SDaniel Drake ---help--- 2707a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2708a0f30f59SDaniel Drake - EC-driven system wakeups 2709a0f30f59SDaniel Drake - AC adapter status updates 2710a0f30f59SDaniel Drake - Battery status updates 2711e279b6c1SSam Ravnborg 2712d4f3e350SEd Wildgooseconfig ALIX 2713d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2714d4f3e350SEd Wildgoose select GPIOLIB 2715d4f3e350SEd Wildgoose ---help--- 2716d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2717d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2718d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2719d4f3e350SEd Wildgoose get added here. 2720d4f3e350SEd Wildgoose 2721d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2722d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2723d4f3e350SEd Wildgoose 2724d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2725d4f3e350SEd Wildgoose 2726da4e3302SPhilip Prindevilleconfig NET5501 2727da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2728da4e3302SPhilip Prindeville select GPIOLIB 2729da4e3302SPhilip Prindeville ---help--- 2730da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2731da4e3302SPhilip Prindeville 27323197059aSPhilip A. Prindevilleconfig GEOS 27333197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27343197059aSPhilip A. Prindeville select GPIOLIB 27353197059aSPhilip A. Prindeville depends on DMI 27363197059aSPhilip A. Prindeville ---help--- 27373197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27383197059aSPhilip A. Prindeville 27397d029125SVivien Didelotconfig TS5500 27407d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27417d029125SVivien Didelot depends on MELAN 27427d029125SVivien Didelot select CHECK_SIGNATURE 27437d029125SVivien Didelot select NEW_LEDS 27447d029125SVivien Didelot select LEDS_CLASS 27457d029125SVivien Didelot ---help--- 27467d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27477d029125SVivien Didelot 2748e279b6c1SSam Ravnborgendif # X86_32 2749e279b6c1SSam Ravnborg 275023ac4ae8SAndreas Herrmannconfig AMD_NB 2751e279b6c1SSam Ravnborg def_bool y 27520e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2753e279b6c1SSam Ravnborg 2754e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2755e279b6c1SSam Ravnborg 2756388b78adSAlexandre Bounineconfig RAPIDIO 2757fdf90abcSAlexandre Bounine tristate "RapidIO support" 2758388b78adSAlexandre Bounine depends on PCI 2759388b78adSAlexandre Bounine default n 2760388b78adSAlexandre Bounine help 2761fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2762388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2763388b78adSAlexandre Bounine 2764388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2765388b78adSAlexandre Bounine 2766e3263ab3SDavid Herrmannconfig X86_SYSFB 2767e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2768e3263ab3SDavid Herrmann help 2769e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2770e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2771e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2772e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2773e3263ab3SDavid Herrmann to x86. 2774e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2775e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2776e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2777e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2778e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2779e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2780e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2781e3263ab3SDavid Herrmann 2782e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2783e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2784e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2785e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2786e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2787e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2788e3263ab3SDavid Herrmann incompatible with simplefb. 2789e3263ab3SDavid Herrmann 2790e3263ab3SDavid Herrmann If unsure, say Y. 2791e3263ab3SDavid Herrmann 2792e279b6c1SSam Ravnborgendmenu 2793e279b6c1SSam Ravnborg 2794e279b6c1SSam Ravnborg 2795e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2796e279b6c1SSam Ravnborg 2797e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2798e279b6c1SSam Ravnborg 2799e279b6c1SSam Ravnborgconfig IA32_EMULATION 2800e279b6c1SSam Ravnborg bool "IA32 Emulation" 2801e279b6c1SSam Ravnborg depends on X86_64 280239f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2803d1603990SRandy Dunlap select BINFMT_ELF 2804a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 280539f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28068f9ca475SIngo Molnar ---help--- 28075fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28085fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28095fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2810e279b6c1SSam Ravnborg 2811e279b6c1SSam Ravnborgconfig IA32_AOUT 2812e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28136b213e1bSDavid Woodhouse depends on IA32_EMULATION 28148f9ca475SIngo Molnar ---help--- 2815e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2816e279b6c1SSam Ravnborg 28170bf62763SH. Peter Anvinconfig X86_X32 28186ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28199b54050bSBrian Gerst depends on X86_64 28205fd92e65SH. J. Lu ---help--- 28215fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28225fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28235fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28245fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28255fd92e65SH. J. Lu 28265fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 28275fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 28285fd92e65SH. J. Lu option set. 28295fd92e65SH. J. Lu 2830953fee1dSIngo Molnarconfig COMPAT_32 2831953fee1dSIngo Molnar def_bool y 2832953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2833953fee1dSIngo Molnar select HAVE_UID16 2834953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2835953fee1dSIngo Molnar 2836e279b6c1SSam Ravnborgconfig COMPAT 28373c2362e6SHarvey Harrison def_bool y 28380bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2839e279b6c1SSam Ravnborg 28403120e25eSJan Beulichif COMPAT 2841e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28423120e25eSJan Beulich def_bool y 2843e279b6c1SSam Ravnborg 2844e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28453c2362e6SHarvey Harrison def_bool y 28463120e25eSJan Beulich depends on SYSVIPC 28473120e25eSJan Beulichendif 2848ee009e4aSDavid Howells 2849e279b6c1SSam Ravnborgendmenu 2850e279b6c1SSam Ravnborg 2851e279b6c1SSam Ravnborg 2852e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2853e5beae16SKeith Packard def_bool y 2854e5beae16SKeith Packard depends on X86_32 2855e5beae16SKeith Packard 28564692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28574692d77fSAlessandro Rubini bool 285883125a3aSAlessandro Rubini depends on X86_64 || STA2X11 28594692d77fSAlessandro Rubini 2860f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2861f7219a53SAlessandro Rubini bool 286283125a3aSAlessandro Rubini depends on STA2X11 2863f7219a53SAlessandro Rubini 2864e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2865e585513bSKirill A. Shutemov def_bool y 2866e585513bSKirill A. Shutemov 2867e279b6c1SSam Ravnborgsource "net/Kconfig" 2868e279b6c1SSam Ravnborg 2869e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2870e279b6c1SSam Ravnborg 2871e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2872e279b6c1SSam Ravnborg 2873e279b6c1SSam Ravnborgsource "fs/Kconfig" 2874e279b6c1SSam Ravnborg 2875e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2876e279b6c1SSam Ravnborg 2877e279b6c1SSam Ravnborgsource "security/Kconfig" 2878e279b6c1SSam Ravnborg 2879e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2880e279b6c1SSam Ravnborg 2881edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2882edf88417SAvi Kivity 2883e279b6c1SSam Ravnborgsource "lib/Kconfig" 2884