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 5667a3e8feSRoss Zwisler select ARCH_HAS_MMIO_FLUSH 57c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 580aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 59d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 606471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 61ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 62ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 63c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 6465f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 656471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 666471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 6777fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 685e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 696471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 703b242c66SMel Gorman select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 716471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 726471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 736471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 746471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 75ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 76da4276b8SIngo Molnar select ARCH_WANT_FRAME_POINTERS 77c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 7838d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 796471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 806471b825SIngo Molnar select CLKEVT_I8253 816471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 826471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 836471b825SIngo Molnar select DCACHE_WORD_ACCESS 8445471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 8545471cd9SLinus Torvalds select EDAC_SUPPORT 866471b825SIngo Molnar select GENERIC_CLOCKEVENTS 876471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 886471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 896471b825SIngo Molnar select GENERIC_CMOS_UPDATE 906471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 916471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 926471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 936471b825SIngo Molnar select GENERIC_IOMAP 94c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 95ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 966471b825SIngo Molnar select GENERIC_IRQ_PROBE 976471b825SIngo Molnar select GENERIC_IRQ_SHOW 986471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 996471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1006471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1016471b825SIngo Molnar select GENERIC_STRNLEN_USER 1026471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1036471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1046471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1056471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1066471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1076471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1086471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 1096471b825SIngo Molnar select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 1106471b825SIngo Molnar select HAVE_ARCH_KGDB 1116471b825SIngo Molnar select HAVE_ARCH_KMEMCHECK 1129e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1139e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1141b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1156471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 1166471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1176471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 118a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 119e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 120c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1216471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1226471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1236471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1246471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 125c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1266471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1276471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1286471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1296471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1309c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 131677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 13206aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 133c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 13458340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1355f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 136644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1376471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1386471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1396471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1406b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1410067f129SK.Prasad select HAVE_HW_BREAKPOINT 1426471b825SIngo Molnar select HAVE_IDE 1436471b825SIngo Molnar select HAVE_IOREMAP_PROT 1446471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1456471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1466471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1476471b825SIngo Molnar select HAVE_KERNEL_GZIP 1486471b825SIngo Molnar select HAVE_KERNEL_LZ4 1496471b825SIngo Molnar select HAVE_KERNEL_LZMA 1506471b825SIngo Molnar select HAVE_KERNEL_LZO 1516471b825SIngo Molnar select HAVE_KERNEL_XZ 1526471b825SIngo Molnar select HAVE_KPROBES 1536471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 1546471b825SIngo Molnar select HAVE_KRETPROBES 1556471b825SIngo Molnar select HAVE_KVM 1566471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1576471b825SIngo Molnar select HAVE_MEMBLOCK 1586471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1590102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 16042a0bb3fSPetr Mladek select HAVE_NMI 1616471b825SIngo Molnar select HAVE_OPROFILE 1626471b825SIngo Molnar select HAVE_OPTPROBES 1636471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1646471b825SIngo Molnar select HAVE_PERF_EVENTS 165c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 16605a4a952SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if HAVE_PERF_EVENTS_NMI 167c5e63197SJiri Olsa select HAVE_PERF_REGS 168c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1696471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 170af085d90SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && FRAME_POINTER && STACK_VALIDATION 171c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1726471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1736471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1747c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 175c0185808SThomas Gleixner select IRQ_FORCED_THREADING 176df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1776471b825SIngo Molnar select PERF_EVENTS 1783195ef59SPrarit Bhargava select RTC_LIB 179d6faca40SArnd Bergmann select RTC_MC146818_LIB 1806471b825SIngo Molnar select SPARSE_IRQ 18183fe27eaSPranith Kumar select SRCU 1826471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 18315f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1846471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1856471b825SIngo Molnar select VIRT_TO_BUS 1866471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1877d8330a5SBalbir Singh 188ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1893120e25eSJan Beulich def_bool y 1903120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 191ba7e4d13SIngo Molnar 19251b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 19351b26adaSLinus Torvalds string 19451b26adaSLinus Torvalds default "elf32-i386" if X86_32 19551b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 19651b26adaSLinus Torvalds 19773531905SSam Ravnborgconfig ARCH_DEFCONFIG 198b9b39bfbSSam Ravnborg string 19973531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 20073531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 201b9b39bfbSSam Ravnborg 2028d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2033c2362e6SHarvey Harrison def_bool y 2048d5fffb9SSam Ravnborg 2058d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2063c2362e6SHarvey Harrison def_bool y 2078d5fffb9SSam Ravnborg 2088d5fffb9SSam Ravnborgconfig MMU 2093c2362e6SHarvey Harrison def_bool y 2108d5fffb9SSam Ravnborg 2119e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2129e08f57dSDaniel Cashman default 28 if 64BIT 2139e08f57dSDaniel Cashman default 8 2149e08f57dSDaniel Cashman 2159e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2169e08f57dSDaniel Cashman default 32 if 64BIT 2179e08f57dSDaniel Cashman default 16 2189e08f57dSDaniel Cashman 2199e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2209e08f57dSDaniel Cashman default 8 2219e08f57dSDaniel Cashman 2229e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2239e08f57dSDaniel Cashman default 16 2249e08f57dSDaniel Cashman 2258d5fffb9SSam Ravnborgconfig SBUS 2268d5fffb9SSam Ravnborg bool 2278d5fffb9SSam Ravnborg 2283bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2293120e25eSJan Beulich def_bool y 230a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2313bc4e459SFUJITA Tomonori 23218e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2334a14d84eSAndrew Morton def_bool y 23418e98307SFUJITA Tomonori 2358d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2363120e25eSJan Beulich def_bool y 2373120e25eSJan Beulich depends on ISA_DMA_API 2388d5fffb9SSam Ravnborg 2398d5fffb9SSam Ravnborgconfig GENERIC_BUG 2403c2362e6SHarvey Harrison def_bool y 2418d5fffb9SSam Ravnborg depends on BUG 242b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 243b93a531eSJan Beulich 244b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 245b93a531eSJan Beulich bool 2468d5fffb9SSam Ravnborg 2478d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2483c2362e6SHarvey Harrison def_bool y 2498d5fffb9SSam Ravnborg 2508d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2513120e25eSJan Beulich def_bool y 2523120e25eSJan Beulich depends on ISA_DMA_API 2538d5fffb9SSam Ravnborg 2541032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2553120e25eSJan Beulich def_bool y 2561032c0baSSam Ravnborg 2571032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2581032c0baSSam Ravnborg def_bool y 2591032c0baSSam Ravnborg 2609a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2619a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2628d5fffb9SSam Ravnborg 2631b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2641b27d05bSPekka Enberg def_bool y 2651b27d05bSPekka Enberg 266dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 26789c9c4c5SBrian Gerst def_bool y 268b32ef636Stravis@sgi.com 26908fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 27008fc4580STejun Heo def_bool y 27108fc4580STejun Heo 27208fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 27311124411STejun Heo def_bool y 27411124411STejun Heo 275801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 276801e4062SJohannes Berg def_bool y 277801e4062SJohannes Berg 278f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 279f4cb5700SJohannes Berg def_bool y 280f4cb5700SJohannes Berg 281cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 282cfe28c5dSSteve Capper def_bool y 283cfe28c5dSSteve Capper 28453313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 28553313b2cSSteve Capper def_bool y 28653313b2cSSteve Capper 2878d5fffb9SSam Ravnborgconfig ZONE_DMA32 288e0fd24a3SJan Beulich def_bool y if X86_64 2898d5fffb9SSam Ravnborg 2908d5fffb9SSam Ravnborgconfig AUDIT_ARCH 291e0fd24a3SJan Beulich def_bool y if X86_64 2928d5fffb9SSam Ravnborg 293765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 294765c68bdSIngo Molnar def_bool y 295765c68bdSIngo Molnar 2966a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 2976a11f75bSAkinobu Mita def_bool y 2986a11f75bSAkinobu Mita 299d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 300d6f2d75aSAndrey Ryabinin hex 301d6f2d75aSAndrey Ryabinin depends on KASAN 3024c7c4483SKirill A. Shutemov default 0xdff8000000000000 if X86_5LEVEL 303d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 304d6f2d75aSAndrey Ryabinin 30569575d38SShane Wangconfig HAVE_INTEL_TXT 30669575d38SShane Wang def_bool y 3076ea30386SKees Cook depends on INTEL_IOMMU && ACPI 30869575d38SShane Wang 3096b0c3d44SSam Ravnborgconfig X86_32_SMP 3106b0c3d44SSam Ravnborg def_bool y 3116b0c3d44SSam Ravnborg depends on X86_32 && SMP 3126b0c3d44SSam Ravnborg 3136b0c3d44SSam Ravnborgconfig X86_64_SMP 3146b0c3d44SSam Ravnborg def_bool y 3156b0c3d44SSam Ravnborg depends on X86_64 && SMP 3166b0c3d44SSam Ravnborg 317ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 318ccbeed3aSTejun Heo def_bool y 31960a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 320ccbeed3aSTejun Heo 3212b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3222b144498SSrikar Dronamraju def_bool y 3232b144498SSrikar Dronamraju 324d20642f0SRob Herringconfig FIX_EARLYCON_MEM 325d20642f0SRob Herring def_bool y 326d20642f0SRob Herring 32798233368SKirill A. Shutemovconfig PGTABLE_LEVELS 32898233368SKirill A. Shutemov int 32998233368SKirill A. Shutemov default 4 if X86_64 33098233368SKirill A. Shutemov default 3 if X86_PAE 33198233368SKirill A. Shutemov default 2 33298233368SKirill A. Shutemov 333506f1d07SSam Ravnborgsource "init/Kconfig" 334dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3358d5fffb9SSam Ravnborg 336506f1d07SSam Ravnborgmenu "Processor type and features" 337506f1d07SSam Ravnborg 3385ee71535SRandy Dunlapconfig ZONE_DMA 3395ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3405ee71535SRandy Dunlap default y 3415ee71535SRandy Dunlap help 3425ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3435ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3445ee71535SRandy Dunlap Disable if no such devices will be used. 3455ee71535SRandy Dunlap 3465ee71535SRandy Dunlap If unsure, say Y. 3475ee71535SRandy Dunlap 348506f1d07SSam Ravnborgconfig SMP 349506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 350506f1d07SSam Ravnborg ---help--- 351506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3524a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3534a474157SRobert Graffham than one CPU, say Y. 354506f1d07SSam Ravnborg 3554a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 356506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 357506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3584a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 359506f1d07SSam Ravnborg will run faster if you say N here. 360506f1d07SSam Ravnborg 361506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 362506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 363506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 364506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 365506f1d07SSam Ravnborg 366506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 367506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 368506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 369506f1d07SSam Ravnborg 370395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 371c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 372506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 373506f1d07SSam Ravnborg 374506f1d07SSam Ravnborg If you don't know what to do here, say N. 375506f1d07SSam Ravnborg 3769def39beSJosh Triplettconfig X86_FEATURE_NAMES 3779def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3789def39beSJosh Triplett default y 3799def39beSJosh Triplett ---help--- 3809def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3819def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3829def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3839def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3849def39beSJosh Triplett 3859def39beSJosh Triplett If in doubt, say Y. 3869def39beSJosh Triplett 3876e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3886e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3896e1315feSBorislav Petkov default y 3906e1315feSBorislav Petkov ---help--- 3916e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 3926e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 3936e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 3946e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 3956e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 3966e1315feSBorislav Petkov slower code. 3976e1315feSBorislav Petkov 39806cd9a7dSYinghai Luconfig X86_X2APIC 39906cd9a7dSYinghai Lu bool "Support x2apic" 40019e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 40106cd9a7dSYinghai Lu ---help--- 40206cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40306cd9a7dSYinghai Lu 40406cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 40506cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 40606cd9a7dSYinghai Lu 40706cd9a7dSYinghai Lu If you don't know what to do here, say N. 40806cd9a7dSYinghai Lu 4096695c85bSYinghai Luconfig X86_MPPARSE 4106e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4117a527688SJan Beulich default y 4125ab74722SIngo Molnar depends on X86_LOCAL_APIC 4138f9ca475SIngo Molnar ---help--- 4146695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4156695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4166695c85bSYinghai Lu 41726f7ef14SYinghai Luconfig X86_BIGSMP 41826f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 41926f7ef14SYinghai Lu depends on X86_32 && SMP 4208f9ca475SIngo Molnar ---help--- 42126f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 422506f1d07SSam Ravnborg 423ddd70cf9SJun Nakajimaconfig GOLDFISH 424ddd70cf9SJun Nakajima def_bool y 425ddd70cf9SJun Nakajima depends on X86_GOLDFISH 426ddd70cf9SJun Nakajima 42778e99b4aSFenghua Yuconfig INTEL_RDT_A 42878e99b4aSFenghua Yu bool "Intel Resource Director Technology Allocation support" 42978e99b4aSFenghua Yu default n 43078e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 43159fe5a77SThomas Gleixner select KERNFS 43278e99b4aSFenghua Yu help 43378e99b4aSFenghua Yu Select to enable resource allocation which is a sub-feature of 43478e99b4aSFenghua Yu Intel Resource Director Technology(RDT). More information about 43578e99b4aSFenghua Yu RDT can be found in the Intel x86 Architecture Software 43678e99b4aSFenghua Yu Developer Manual. 43778e99b4aSFenghua Yu 43878e99b4aSFenghua Yu Say N if unsure. 43978e99b4aSFenghua Yu 4408425091fSRavikiran G Thirumalaiif X86_32 441c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 442c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 443c5c606d9SRavikiran G Thirumalai default y 4448f9ca475SIngo Molnar ---help--- 44506ac8346SIngo Molnar If you disable this option then the kernel will only support 44606ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 44706ac8346SIngo Molnar systems out there.) 44806ac8346SIngo Molnar 4498425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4508425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 451cb7b8023SBen Hutchings Goldfish (Android emulator) 4528425091fSRavikiran G Thirumalai AMD Elan 4538425091fSRavikiran G Thirumalai RDC R-321x SoC 4548425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 45583125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4563f4110a4SThomas Gleixner Moorestown MID devices 45706ac8346SIngo Molnar 45806ac8346SIngo Molnar If you have one of these systems, or if you want to build a 45906ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4608425091fSRavikiran G Thirumalaiendif 46106ac8346SIngo Molnar 4628425091fSRavikiran G Thirumalaiif X86_64 4638425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4648425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4658425091fSRavikiran G Thirumalai default y 4668425091fSRavikiran G Thirumalai ---help--- 4678425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4688425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4698425091fSRavikiran G Thirumalai systems out there.) 4708425091fSRavikiran G Thirumalai 4718425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4728425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 47344b111b5SSteffen Persvold Numascale NumaChip 4748425091fSRavikiran G Thirumalai ScaleMP vSMP 4758425091fSRavikiran G Thirumalai SGI Ultraviolet 4768425091fSRavikiran G Thirumalai 4778425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4788425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4798425091fSRavikiran G Thirumalaiendif 480c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 481c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 48244b111b5SSteffen Persvoldconfig X86_NUMACHIP 48344b111b5SSteffen Persvold bool "Numascale NumaChip" 48444b111b5SSteffen Persvold depends on X86_64 48544b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 48644b111b5SSteffen Persvold depends on NUMA 48744b111b5SSteffen Persvold depends on SMP 48844b111b5SSteffen Persvold depends on X86_X2APIC 489f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 49044b111b5SSteffen Persvold ---help--- 49144b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 49244b111b5SSteffen Persvold enable more than ~168 cores. 49344b111b5SSteffen Persvold If you don't have one of these, you should say N here. 49403b48632SNick Piggin 4956a48565eSIngo Molnarconfig X86_VSMP 496c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 4976276a074SBorislav Petkov select HYPERVISOR_GUEST 4986a48565eSIngo Molnar select PARAVIRT 4996a48565eSIngo Molnar depends on X86_64 && PCI 500c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 501ead91d4bSShai Fultheim depends on SMP 5028f9ca475SIngo Molnar ---help--- 5036a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5046a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5056a48565eSIngo Molnar if you have one of these machines. 5066a48565eSIngo Molnar 507c5c606d9SRavikiran G Thirumalaiconfig X86_UV 508c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 509c5c606d9SRavikiran G Thirumalai depends on X86_64 510c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 51154c28d29SJack Steiner depends on NUMA 5121ecb4ae5SAndrew Morton depends on EFI 5139d6c26e7SSuresh Siddha depends on X86_X2APIC 5141222e564SIngo Molnar depends on PCI 515c5c606d9SRavikiran G Thirumalai ---help--- 516c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 517c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 518c5c606d9SRavikiran G Thirumalai 519c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 520c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 521506f1d07SSam Ravnborg 522ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 523ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 524cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 525ddd70cf9SJun Nakajima ---help--- 526ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 527ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 528ddd70cf9SJun Nakajima Goldfish emulator say N here. 529ddd70cf9SJun Nakajima 530c751e17bSThomas Gleixnerconfig X86_INTEL_CE 531c751e17bSThomas Gleixner bool "CE4100 TV platform" 532c751e17bSThomas Gleixner depends on PCI 533c751e17bSThomas Gleixner depends on PCI_GODIRECT 5346084a6e2SJiang Liu depends on X86_IO_APIC 535c751e17bSThomas Gleixner depends on X86_32 536c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 53737bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 538da6b737bSSebastian Andrzej Siewior select OF 539da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 540c751e17bSThomas Gleixner ---help--- 541c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 542c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 543c751e17bSThomas Gleixner boxes and media devices. 544c751e17bSThomas Gleixner 5454cb9b00fSDavid Cohenconfig X86_INTEL_MID 54643605ef1SAlan Cox bool "Intel MID platform support" 54743605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 548edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5491ea7c673SAlan Cox depends on PCI 5503fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5511ea7c673SAlan Cox depends on X86_IO_APIC 5527c9c3a1eSAlan Cox select SFI 5534cb9b00fSDavid Cohen select I2C 5547c9c3a1eSAlan Cox select DW_APB_TIMER 5551ea7c673SAlan Cox select APB_TIMER 5561ea7c673SAlan Cox select INTEL_SCU_IPC 55715a713dfSMika Westerberg select MFD_INTEL_MSIC 5581ea7c673SAlan Cox ---help--- 5594cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5604cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5614cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5621ea7c673SAlan Cox 5634cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5644cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 56543605ef1SAlan Cox 5668bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5678bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5688bbc2a13SBryan O'Donoghue depends on X86_32 5698bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5708bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5718bbc2a13SBryan O'Donoghue depends on X86_TSC 5728bbc2a13SBryan O'Donoghue depends on PCI 5738bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5748bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5758bbc2a13SBryan O'Donoghue select IOSF_MBI 5768bbc2a13SBryan O'Donoghue select INTEL_IMR 5779ab6eb51SAndy Shevchenko select COMMON_CLK 5788bbc2a13SBryan O'Donoghue ---help--- 5798bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5808bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5818bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5828bbc2a13SBryan O'Donoghue 5833d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5843d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 585eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5863d48aab1SMika Westerberg select COMMON_CLK 5870f531431SMathias Nyman select PINCTRL 588eebb3e8dSAndy Shevchenko select IOSF_MBI 5893d48aab1SMika Westerberg ---help--- 5903d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 5913d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 5920f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 5930f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 5943d48aab1SMika Westerberg 59592082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 59692082a88SKen Xue bool "AMD ACPI2Platform devices support" 59792082a88SKen Xue depends on ACPI 59892082a88SKen Xue select COMMON_CLK 59992082a88SKen Xue select PINCTRL 60092082a88SKen Xue ---help--- 60192082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 60292082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 60392082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 60492082a88SKen Xue implemented under PINCTRL subsystem. 60592082a88SKen Xue 606ced3ce76SDavid E. Boxconfig IOSF_MBI 607ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 608ced3ce76SDavid E. Box depends on PCI 609ced3ce76SDavid E. Box ---help--- 610ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 611ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 612ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 613ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 614ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 615ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 616ced3ce76SDavid E. Box This list is not meant to be exclusive. 617ced3ce76SDavid E. Box - BayTrail 618ced3ce76SDavid E. Box - Braswell 619ced3ce76SDavid E. Box - Quark 620ced3ce76SDavid E. Box 621ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 622ced3ce76SDavid E. Box 623ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 624ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 625ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 626ed2226bdSDavid E. Box ---help--- 627ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 628ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 629ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 630ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 631ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 632ed2226bdSDavid E. Box device they want to access. 633ed2226bdSDavid E. Box 634ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 635ed2226bdSDavid E. Box 636c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 637c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 638506f1d07SSam Ravnborg depends on X86_32 639c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 640c5c606d9SRavikiran G Thirumalai select M486 641c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 642c5c606d9SRavikiran G Thirumalai ---help--- 643c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 644c5c606d9SRavikiran G Thirumalai as R-8610-(G). 645c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 646c5c606d9SRavikiran G Thirumalai 647e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6489c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6499c398017SIngo Molnar depends on X86_32 && SMP 650c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6518f9ca475SIngo Molnar ---help--- 652b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 653b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 654b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 655b5660ba7SH. Peter Anvin one and will fallback to default. 656d49c4288SYinghai Lu 657c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 658d49c4288SYinghai Lu 659d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6606fc108a0SJan Beulich def_bool y 661d949f36fSLinus Torvalds # MCE code calls memory_failure(): 662d949f36fSLinus Torvalds depends on X86_MCE 663d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 664d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 665d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 666d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 667d949f36fSLinus Torvalds 66883125a3aSAlessandro Rubiniconfig STA2X11 66983125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 67083125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 67183125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 67283125a3aSAlessandro Rubini select X86_DMA_REMAP 67383125a3aSAlessandro Rubini select SWIOTLB 67483125a3aSAlessandro Rubini select MFD_STA2X11 6750145071bSLinus Walleij select GPIOLIB 67683125a3aSAlessandro Rubini default n 67783125a3aSAlessandro Rubini ---help--- 67883125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 67983125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 68083125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 68183125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 68283125a3aSAlessandro Rubini standard PC machines. 68383125a3aSAlessandro Rubini 68482148d1dSShérabconfig X86_32_IRIS 68582148d1dSShérab tristate "Eurobraille/Iris poweroff module" 68682148d1dSShérab depends on X86_32 68782148d1dSShérab ---help--- 68882148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 68982148d1dSShérab to shut themselves down properly. A special I/O sequence is 69082148d1dSShérab needed to do so, which is what this module does at 69182148d1dSShérab kernel shutdown. 69282148d1dSShérab 69382148d1dSShérab This is only for Iris machines from EuroBraille. 69482148d1dSShérab 69582148d1dSShérab If unused, say N. 69682148d1dSShérab 697ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 6983c2362e6SHarvey Harrison def_bool y 6993c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 700a87d0914SKen Chen depends on X86 7018f9ca475SIngo Molnar ---help--- 702506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 703506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 704506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 705506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 706506f1d07SSam Ravnborg 707506f1d07SSam Ravnborg If in doubt, say "Y". 708506f1d07SSam Ravnborg 7096276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7106276a074SBorislav Petkov bool "Linux guest support" 7118f9ca475SIngo Molnar ---help--- 7126276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7136276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7146276a074SBorislav Petkov setup. 715506f1d07SSam Ravnborg 7166276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7176276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 718506f1d07SSam Ravnborg 7196276a074SBorislav Petkovif HYPERVISOR_GUEST 720506f1d07SSam Ravnborg 721e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 722e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7238f9ca475SIngo Molnar ---help--- 724e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 725e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 726e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 727e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 728e61bd94aSEduardo Pereira Habkost 7296276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7306276a074SBorislav Petkov bool "paravirt-ops debugging" 7316276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7326276a074SBorislav Petkov ---help--- 7336276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7346276a074SBorislav Petkov a paravirt_op is missing when it is called. 7356276a074SBorislav Petkov 736b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 737b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7386ea30386SKees Cook depends on PARAVIRT && SMP 739b4ecc126SJeremy Fitzhardinge ---help--- 740b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 741b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 742b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 743b4ecc126SJeremy Fitzhardinge 7444c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7454c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 746b4ecc126SJeremy Fitzhardinge 7474c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 748b4ecc126SJeremy Fitzhardinge 74945e898b7SWaiman Longconfig QUEUED_LOCK_STAT 75045e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 751cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 75245e898b7SWaiman Long ---help--- 75345e898b7SWaiman Long Enable the collection of statistical data on the slowpath 75445e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 75545e898b7SWaiman Long them on debugfs. 75645e898b7SWaiman Long 7576276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7586276a074SBorislav Petkov 7596276a074SBorislav Petkovconfig KVM_GUEST 7606276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7616276a074SBorislav Petkov depends on PARAVIRT 7626276a074SBorislav Petkov select PARAVIRT_CLOCK 7636276a074SBorislav Petkov default y 7646276a074SBorislav Petkov ---help--- 7656276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7666276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7676276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7686276a074SBorislav Petkov underlying device model, the host provides the guest with 7696276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7706276a074SBorislav Petkov 7711e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7721e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7731e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7741e20eb85SSrivatsa Vaddagiri default n 7751e20eb85SSrivatsa Vaddagiri ---help--- 7761e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7771e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7781e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7791e20eb85SSrivatsa Vaddagiri 7806276a074SBorislav Petkovsource "arch/x86/lguest/Kconfig" 7816276a074SBorislav Petkov 7826276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7836276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7846276a074SBorislav Petkov depends on PARAVIRT 7856276a074SBorislav Petkov default n 7866276a074SBorislav Petkov ---help--- 7876276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7886276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7896276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 7906276a074SBorislav Petkov that, there can be a small performance impact. 7916276a074SBorislav Petkov 7926276a074SBorislav Petkov If in doubt, say N here. 7936276a074SBorislav Petkov 7947af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 7957af192c9SGerd Hoffmann bool 7967af192c9SGerd Hoffmann 7976276a074SBorislav Petkovendif #HYPERVISOR_GUEST 79897349135SJeremy Fitzhardinge 79908677214SYinghai Luconfig NO_BOOTMEM 800774ea0bcSYinghai Lu def_bool y 80108677214SYinghai Lu 802506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 803506f1d07SSam Ravnborg 804506f1d07SSam Ravnborgconfig HPET_TIMER 8053c2362e6SHarvey Harrison def_bool X86_64 806506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8078f9ca475SIngo Molnar ---help--- 808506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 809506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 810506f1d07SSam Ravnborg present. 811506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 812506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 813506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8144e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8154e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 816506f1d07SSam Ravnborg 817506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 818506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 819506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 820506f1d07SSam Ravnborg 821506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 822506f1d07SSam Ravnborg 823506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8243c2362e6SHarvey Harrison def_bool y 8259d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 826506f1d07SSam Ravnborg 827bb24c471SJacob Panconfig APB_TIMER 828933b9463SAlan Cox def_bool y if X86_INTEL_MID 829933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 83006c3df49SJamie Iles select DW_APB_TIMER 831a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 832bb24c471SJacob Pan help 833bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 834bb24c471SJacob Pan The APBT provides a stable time base on SMP 835bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 836bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 837bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 838bb24c471SJacob Pan 8396a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 840506f1d07SSam Ravnborg# The code disables itself when not needed. 8417ae9392cSThomas Petazzoniconfig DMI 8427ae9392cSThomas Petazzoni default y 843cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8446a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8458f9ca475SIngo Molnar ---help--- 8467ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8477ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8487ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8497ae9392cSThomas Petazzoni BIOS code. 8507ae9392cSThomas Petazzoni 851506f1d07SSam Ravnborgconfig GART_IOMMU 85238901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 853506f1d07SSam Ravnborg select SWIOTLB 85423ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8558f9ca475SIngo Molnar ---help--- 856ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 857ced3c42cSIngo Molnar GART based hardware IOMMUs. 858ced3c42cSIngo Molnar 859ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 860ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 861ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 862ced3c42cSIngo Molnar 863ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 864ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 865ced3c42cSIngo Molnar 866ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 867ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 868ced3c42cSIngo Molnar 32-bit limited device. 869ced3c42cSIngo Molnar 870ced3c42cSIngo Molnar If unsure, say Y. 871506f1d07SSam Ravnborg 872506f1d07SSam Ravnborgconfig CALGARY_IOMMU 873506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 874506f1d07SSam Ravnborg select SWIOTLB 8756ea30386SKees Cook depends on X86_64 && PCI 8768f9ca475SIngo Molnar ---help--- 877506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 878506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 879506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 880506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 881506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 882506f1d07SSam Ravnborg prevents them from going anywhere except their intended 883506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 884506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 885506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 886506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 887506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 888506f1d07SSam Ravnborg If unsure, say Y. 889506f1d07SSam Ravnborg 890506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 8913c2362e6SHarvey Harrison def_bool y 8923c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 893506f1d07SSam Ravnborg depends on CALGARY_IOMMU 8948f9ca475SIngo Molnar ---help--- 895506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 896506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 897506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 898506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 899506f1d07SSam Ravnborg If unsure, say Y. 900506f1d07SSam Ravnborg 901506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 902506f1d07SSam Ravnborgconfig SWIOTLB 903a1afd01cSJoerg Roedel def_bool y if X86_64 9048f9ca475SIngo Molnar ---help--- 905506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9064454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9074454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9084454d327SJoe Millenbach with more than 3 GB of memory. 9094454d327SJoe Millenbach If unsure, say Y. 910506f1d07SSam Ravnborg 911a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9123120e25eSJan Beulich def_bool y 9133120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 914d25e26b6SLinus Torvalds 9151184dc2fSMike Travisconfig MAXSMP 916ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9176ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 91836f5101aSMike Travis select CPUMASK_OFFSTACK 9198f9ca475SIngo Molnar ---help--- 920ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9211184dc2fSMike Travis If unsure, say N. 922506f1d07SSam Ravnborg 923506f1d07SSam Ravnborgconfig NR_CPUS 92436f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 9252a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 926bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 927b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 92878637a97SMike Travis default "1" if !SMP 929b53b5edaSJosh Boyer default "8192" if MAXSMP 930b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 931c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 932c5c19941SKirill A. Shutemov default "64" if SMP 9338f9ca475SIngo Molnar ---help--- 934506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 935bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 936cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 937506f1d07SSam Ravnborg minimum value which makes sense is 2. 938506f1d07SSam Ravnborg 939506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 940506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 941506f1d07SSam Ravnborg 942506f1d07SSam Ravnborgconfig SCHED_SMT 943506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 944c8e56d20SBorislav Petkov depends on SMP 9458f9ca475SIngo Molnar ---help--- 946506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 947506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 948506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 949506f1d07SSam Ravnborg N here. 950506f1d07SSam Ravnborg 951506f1d07SSam Ravnborgconfig SCHED_MC 9523c2362e6SHarvey Harrison def_bool y 9533c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 954c8e56d20SBorislav Petkov depends on SMP 9558f9ca475SIngo Molnar ---help--- 956506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 957506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 958506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 959506f1d07SSam Ravnborg 960de966cf4STim Chenconfig SCHED_MC_PRIO 961de966cf4STim Chen bool "CPU core priorities scheduler support" 9620a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 9630a21fc12SIngo Molnar select X86_INTEL_PSTATE 9640a21fc12SIngo Molnar select CPU_FREQ 965de966cf4STim Chen default y 9665e76b2abSTim Chen ---help--- 967de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 968de966cf4STim Chen core ordering determined at manufacturing time, which allows 969de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 970de966cf4STim Chen single threaded workloads) than others. 971de966cf4STim Chen 972de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 973de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 974de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 975de966cf4STim Chen overall system performance can be achieved. 976de966cf4STim Chen 977de966cf4STim Chen This feature will have no effect on CPUs without this feature. 978de966cf4STim Chen 979de966cf4STim Chen If unsure say Y here. 9805e76b2abSTim Chen 981506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 982506f1d07SSam Ravnborg 98330b8b006SThomas Gleixnerconfig UP_LATE_INIT 98430b8b006SThomas Gleixner def_bool y 985ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 98630b8b006SThomas Gleixner 987506f1d07SSam Ravnborgconfig X86_UP_APIC 98850849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 98950849eefSJan Beulich default PCI_MSI 99038a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 9918f9ca475SIngo Molnar ---help--- 992506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 993506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 994506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 995506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 996506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 997506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 998506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 999506f1d07SSam Ravnborg lockups. 1000506f1d07SSam Ravnborg 1001506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1002506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1003506f1d07SSam Ravnborg depends on X86_UP_APIC 10048f9ca475SIngo Molnar ---help--- 1005506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1006506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1007506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1008506f1d07SSam Ravnborg 1009506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1010506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1011506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1012506f1d07SSam Ravnborg 1013506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10143c2362e6SHarvey Harrison def_bool y 10150dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1016b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 101752f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1018506f1d07SSam Ravnborg 1019506f1d07SSam Ravnborgconfig X86_IO_APIC 1020b1da1e71SJan Beulich def_bool y 1021b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1022506f1d07SSam Ravnborg 102341b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 102441b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 102541b9eb26SStefan Assmann depends on X86_IO_APIC 10268f9ca475SIngo Molnar ---help--- 102741b9eb26SStefan Assmann This option enables a workaround that fixes a source of 102841b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 102941b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 103041b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 103141b9eb26SStefan Assmann 103241b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 103341b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 103441b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 103541b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 103641b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 103741b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 103841b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 103941b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 104041b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 104141b9eb26SStefan Assmann down (vital) interrupt lines. 104241b9eb26SStefan Assmann 104341b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 104441b9eb26SStefan Assmann increased on these systems. 104541b9eb26SStefan Assmann 1046506f1d07SSam Ravnborgconfig X86_MCE 1047bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1048648ed940SChen, Gong select GENERIC_ALLOCATOR 1049e57dbaf7SBorislav Petkov default y 1050506f1d07SSam Ravnborg ---help--- 1051bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1052bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1053506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1054bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10554efc0670SAndi Kleen 10565de97c9fSTony Luckconfig X86_MCELOG_LEGACY 10575de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 10585de97c9fSTony Luck depends on X86_MCE 10595de97c9fSTony Luck ---help--- 10605de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 10615de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 10625de97c9fSTony Luck rasdaemon solution. 10635de97c9fSTony Luck 1064506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10653c2362e6SHarvey Harrison def_bool y 10663c2362e6SHarvey Harrison prompt "Intel MCE features" 1067c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10688f9ca475SIngo Molnar ---help--- 1069506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1070506f1d07SSam Ravnborg the thermal monitor. 1071506f1d07SSam Ravnborg 1072506f1d07SSam Ravnborgconfig X86_MCE_AMD 10733c2362e6SHarvey Harrison def_bool y 10743c2362e6SHarvey Harrison prompt "AMD MCE features" 1075f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 10768f9ca475SIngo Molnar ---help--- 1077506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1078506f1d07SSam Ravnborg the DRAM Error Threshold. 1079506f1d07SSam Ravnborg 10804efc0670SAndi Kleenconfig X86_ANCIENT_MCE 10816fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1082c31d9633SAndi Kleen depends on X86_32 && X86_MCE 10834efc0670SAndi Kleen ---help--- 10844efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 10855065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 10864efc0670SAndi Kleen line. 10874efc0670SAndi Kleen 1088b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1089b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 10906fc108a0SJan Beulich def_bool y 1091b2762686SAndi Kleen 1092ea149b36SAndi Kleenconfig X86_MCE_INJECT 1093bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1094ea149b36SAndi Kleen tristate "Machine check injector support" 1095ea149b36SAndi Kleen ---help--- 1096ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1097ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1098ea149b36SAndi Kleen QA it is safe to say n. 1099ea149b36SAndi Kleen 11004efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11014efc0670SAndi Kleen def_bool y 11025bb38adcSAndi Kleen depends on X86_MCE_INTEL 11034efc0670SAndi Kleen 110407dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1105e633c65aSKan Liang 11065aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11071e642812SIngo Molnar bool "Legacy VM86 support" 11085aef51c3SAndy Lutomirski default n 1109506f1d07SSam Ravnborg depends on X86_32 11108f9ca475SIngo Molnar ---help--- 11115aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11125aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11135aef51c3SAndy Lutomirski 11145aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11155aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11165aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11175aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11185aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11191e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11201e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11211e642812SIngo Molnar mode might be faster than emulation and you might want to 11221e642812SIngo Molnar enable this option. 11235aef51c3SAndy Lutomirski 11241e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11251e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11261e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11271e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11285aef51c3SAndy Lutomirski 11291e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11301e642812SIngo Molnar and slows down exception handling a tiny bit. 11315aef51c3SAndy Lutomirski 11321e642812SIngo Molnar If unsure, say N here. 11335aef51c3SAndy Lutomirski 11345aef51c3SAndy Lutomirskiconfig VM86 11355aef51c3SAndy Lutomirski bool 11365aef51c3SAndy Lutomirski default X86_LEGACY_VM86 113734273f41SH. Peter Anvin 113834273f41SH. Peter Anvinconfig X86_16BIT 113934273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 114034273f41SH. Peter Anvin default y 1141a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 114234273f41SH. Peter Anvin ---help--- 114334273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 114434273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 114534273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 114634273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 114734273f41SH. Peter Anvin 114834273f41SH. Peter Anvinconfig X86_ESPFIX32 114934273f41SH. Peter Anvin def_bool y 115034273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1151506f1d07SSam Ravnborg 1152197725deSH. Peter Anvinconfig X86_ESPFIX64 1153197725deSH. Peter Anvin def_bool y 115434273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1155506f1d07SSam Ravnborg 11561ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 11571ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 11581ad83c85SAndy Lutomirski default y 11591ad83c85SAndy Lutomirski depends on X86_64 11601ad83c85SAndy Lutomirski ---help--- 11611ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 11621ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 11631ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11641ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11651ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11661ad83c85SAndy Lutomirski 0xffffffffff600?00. 11671ad83c85SAndy Lutomirski 11681ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 11691ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 11701ad83c85SAndy Lutomirski 11711ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 11721ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 11731ad83c85SAndy Lutomirski 1174506f1d07SSam Ravnborgconfig TOSHIBA 1175506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1176506f1d07SSam Ravnborg depends on X86_32 1177506f1d07SSam Ravnborg ---help--- 1178506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1179506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1180506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1181506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1182506f1d07SSam Ravnborg 1183506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1184506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1185506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1186506f1d07SSam Ravnborg 1187506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1188506f1d07SSam Ravnborg Say N otherwise. 1189506f1d07SSam Ravnborg 1190506f1d07SSam Ravnborgconfig I8K 1191039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1192949a9d70SJean Delvare select HWMON 1193039ae585SPali Rohár select SENSORS_DELL_SMM 1194506f1d07SSam Ravnborg ---help--- 1195039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1196039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1197039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1198039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1199039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1200039ae585SPali Rohár needed userspace package i8kutils. 1201506f1d07SSam Ravnborg 1202039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1203039ae585SPali Rohár use userspace package i8kutils. 1204506f1d07SSam Ravnborg Say N otherwise. 1205506f1d07SSam Ravnborg 1206506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12079ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12089ba16087SJan Beulich depends on X86_32 1209506f1d07SSam Ravnborg ---help--- 1210506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1211506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1212506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1213506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1214506f1d07SSam Ravnborg system. 1215506f1d07SSam Ravnborg 1216506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12175e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1218506f1d07SSam Ravnborg 1219506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1220506f1d07SSam Ravnborg enable this option even if you don't need it. 1221506f1d07SSam Ravnborg Say N otherwise. 1222506f1d07SSam Ravnborg 1223506f1d07SSam Ravnborgconfig MICROCODE 12249a2bc335SBorislav Petkov bool "CPU microcode loading support" 12259a2bc335SBorislav Petkov default y 122680030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1227506f1d07SSam Ravnborg select FW_LOADER 1228506f1d07SSam Ravnborg ---help--- 1229506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12305f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12315f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12325f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12335f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12345f9c01aaSBorislav Petkov the Linux kernel. 1235506f1d07SSam Ravnborg 12365f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12375f9c01aaSBorislav Petkov in Documentation/x86/early-microcode.txt. For that you need to enable 12385f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12395f9c01aaSBorislav Petkov initrd for microcode blobs. 1240506f1d07SSam Ravnborg 12415f9c01aaSBorislav Petkov In addition, you can build-in the microcode into the kernel. For that you 12425f9c01aaSBorislav Petkov need to enable FIRMWARE_IN_KERNEL and add the vendor-supplied microcode 12435f9c01aaSBorislav Petkov to the CONFIG_EXTRA_FIRMWARE config option. 1244506f1d07SSam Ravnborg 12458d86f390SPeter Orubaconfig MICROCODE_INTEL 1246e43f6e67SBorislav Petkov bool "Intel microcode loading support" 12478d86f390SPeter Oruba depends on MICROCODE 12488d86f390SPeter Oruba default MICROCODE 12498d86f390SPeter Oruba select FW_LOADER 12508f9ca475SIngo Molnar ---help--- 12518d86f390SPeter Oruba This options enables microcode patch loading support for Intel 12528d86f390SPeter Oruba processors. 12538d86f390SPeter Oruba 1254b8989db9SAlan For the current Intel microcode data package go to 1255b8989db9SAlan <https://downloadcenter.intel.com> and search for 1256b8989db9SAlan 'Linux Processor Microcode Data File'. 12578d86f390SPeter Oruba 125880cc9f10SPeter Orubaconfig MICROCODE_AMD 1259e43f6e67SBorislav Petkov bool "AMD microcode loading support" 126080cc9f10SPeter Oruba depends on MICROCODE 126180cc9f10SPeter Oruba select FW_LOADER 12628f9ca475SIngo Molnar ---help--- 126380cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 126480cc9f10SPeter Oruba processors will be enabled. 126580cc9f10SPeter Oruba 1266506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12673c2362e6SHarvey Harrison def_bool y 1268506f1d07SSam Ravnborg depends on MICROCODE 1269506f1d07SSam Ravnborg 1270506f1d07SSam Ravnborgconfig X86_MSR 1271506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 12728f9ca475SIngo Molnar ---help--- 1273506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1274506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1275506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1276506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1277506f1d07SSam Ravnborg systems. 1278506f1d07SSam Ravnborg 1279506f1d07SSam Ravnborgconfig X86_CPUID 1280506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 12818f9ca475SIngo Molnar ---help--- 1282506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1283506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1284506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1285506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1286506f1d07SSam Ravnborg 1287506f1d07SSam Ravnborgchoice 1288506f1d07SSam Ravnborg prompt "High Memory Support" 12896fc108a0SJan Beulich default HIGHMEM4G 1290506f1d07SSam Ravnborg depends on X86_32 1291506f1d07SSam Ravnborg 1292506f1d07SSam Ravnborgconfig NOHIGHMEM 1293506f1d07SSam Ravnborg bool "off" 1294506f1d07SSam Ravnborg ---help--- 1295506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1296506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1297506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1298506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1299506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1300506f1d07SSam Ravnborg "high memory". 1301506f1d07SSam Ravnborg 1302506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1303506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1304506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1305506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1306506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1307506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1308506f1d07SSam Ravnborg possible. 1309506f1d07SSam Ravnborg 1310506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1311506f1d07SSam Ravnborg answer "4GB" here. 1312506f1d07SSam Ravnborg 1313506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1314506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1315506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1316506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1317506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1318506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1319506f1d07SSam Ravnborg 1320506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1321506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1322506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1323506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1324506f1d07SSam Ravnborg kernel at boot time.) 1325506f1d07SSam Ravnborg 1326506f1d07SSam Ravnborg If unsure, say "off". 1327506f1d07SSam Ravnborg 1328506f1d07SSam Ravnborgconfig HIGHMEM4G 1329506f1d07SSam Ravnborg bool "4GB" 13308f9ca475SIngo Molnar ---help--- 1331506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1332506f1d07SSam Ravnborg gigabytes of physical RAM. 1333506f1d07SSam Ravnborg 1334506f1d07SSam Ravnborgconfig HIGHMEM64G 1335506f1d07SSam Ravnborg bool "64GB" 1336eb068e78SH. Peter Anvin depends on !M486 1337506f1d07SSam Ravnborg select X86_PAE 13388f9ca475SIngo Molnar ---help--- 1339506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1340506f1d07SSam Ravnborg gigabytes of physical RAM. 1341506f1d07SSam Ravnborg 1342506f1d07SSam Ravnborgendchoice 1343506f1d07SSam Ravnborg 1344506f1d07SSam Ravnborgchoice 13456a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1346506f1d07SSam Ravnborg default VMSPLIT_3G 1347506f1d07SSam Ravnborg depends on X86_32 13488f9ca475SIngo Molnar ---help--- 1349506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1350506f1d07SSam Ravnborg 1351506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1352506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1353506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1354506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1355506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1356506f1d07SSam Ravnborg available to user programs, making the address space there 1357506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1358506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1359506f1d07SSam Ravnborg kernel modules. 1360506f1d07SSam Ravnborg 1361506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1362506f1d07SSam Ravnborg option alone! 1363506f1d07SSam Ravnborg 1364506f1d07SSam Ravnborg config VMSPLIT_3G 1365506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1366506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1367506f1d07SSam Ravnborg depends on !X86_PAE 1368506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1369506f1d07SSam Ravnborg config VMSPLIT_2G 1370506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1371506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1372506f1d07SSam Ravnborg depends on !X86_PAE 1373506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1374506f1d07SSam Ravnborg config VMSPLIT_1G 1375506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1376506f1d07SSam Ravnborgendchoice 1377506f1d07SSam Ravnborg 1378506f1d07SSam Ravnborgconfig PAGE_OFFSET 1379506f1d07SSam Ravnborg hex 1380506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1381506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1382506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1383506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1384506f1d07SSam Ravnborg default 0xC0000000 1385506f1d07SSam Ravnborg depends on X86_32 1386506f1d07SSam Ravnborg 1387506f1d07SSam Ravnborgconfig HIGHMEM 13883c2362e6SHarvey Harrison def_bool y 1389506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1390506f1d07SSam Ravnborg 1391506f1d07SSam Ravnborgconfig X86_PAE 13929ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1393506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 13949d99c712SChristian Melki select SWIOTLB 13958f9ca475SIngo Molnar ---help--- 1396506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1397506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1398506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1399506f1d07SSam Ravnborg consumes more pagetable space per process. 1400506f1d07SSam Ravnborg 1401600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14023120e25eSJan Beulich def_bool y 14033120e25eSJan Beulich depends on X86_64 || X86_PAE 1404600715dcSJeremy Fitzhardinge 140566f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14063120e25eSJan Beulich def_bool y 14073120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 140866f2b061SFUJITA Tomonori 140910971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1410e5008abeSLuis R. Rodriguez def_bool y 1411e5008abeSLuis R. Rodriguez depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 14128f9ca475SIngo Molnar ---help--- 141310971ab2SIngo Molnar Certain kernel features effectively disable kernel 141410971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 141510971ab2SIngo Molnar supports them), so don't confuse the user by printing 141610971ab2SIngo Molnar that we have them enabled. 14179e899816SNick Piggin 14187744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 14197744ccdbSTom Lendacky def_bool y 14207744ccdbSTom Lendacky 14217744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 14227744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 14237744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 14247744ccdbSTom Lendacky ---help--- 14257744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 14267744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 14277744ccdbSTom Lendacky Encryption (SME). 14287744ccdbSTom Lendacky 14297744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 14307744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 14317744ccdbSTom Lendacky default y 14327744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 14337744ccdbSTom Lendacky ---help--- 14347744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 14357744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 14367744ccdbSTom Lendacky 14377744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 14387744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 14397744ccdbSTom Lendacky 14407744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 14417744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 14427744ccdbSTom Lendacky 1443*f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1444*f88a68faSTom Lendacky def_bool y 1445*f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1446*f88a68faSTom Lendacky 1447506f1d07SSam Ravnborg# Common NUMA Features 1448506f1d07SSam Ravnborgconfig NUMA 1449fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1450506f1d07SSam Ravnborg depends on SMP 1451b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1452b5660ba7SH. Peter Anvin default y if X86_BIGSMP 14538f9ca475SIngo Molnar ---help--- 1454506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1455fd51b2d7SKOSAKI Motohiro 1456506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1457506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1458506f1d07SSam Ravnborg NUMA awareness to the kernel. 1459506f1d07SSam Ravnborg 1460c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1461fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1462fd51b2d7SKOSAKI Motohiro 1463b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 14647cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1465fd51b2d7SKOSAKI Motohiro 1466fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1467506f1d07SSam Ravnborg 1468eec1d4faSHans Rosenfeldconfig AMD_NUMA 14693c2362e6SHarvey Harrison def_bool y 14703c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 14715da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 14728f9ca475SIngo Molnar ---help--- 1473eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1474eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1475eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1476eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1477eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1478506f1d07SSam Ravnborg 1479506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 14803c2362e6SHarvey Harrison def_bool y 14813c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1482506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1483506f1d07SSam Ravnborg select ACPI_NUMA 14848f9ca475SIngo Molnar ---help--- 1485506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1486506f1d07SSam Ravnborg 14876ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 14886ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 14896ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 14906ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 14916ec6e0d9SSuresh Siddha# for details. 14926ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 14936ec6e0d9SSuresh Siddha def_bool y 14946ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 14956ec6e0d9SSuresh Siddha 1496506f1d07SSam Ravnborgconfig NUMA_EMU 1497506f1d07SSam Ravnborg bool "NUMA emulation" 14981b7e03efSTejun Heo depends on NUMA 14998f9ca475SIngo Molnar ---help--- 1500506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1501506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1502506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1503506f1d07SSam Ravnborg 1504506f1d07SSam Ravnborgconfig NODES_SHIFT 1505d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 150651591e31SDavid Rientjes range 1 10 150751591e31SDavid Rientjes default "10" if MAXSMP 1508506f1d07SSam Ravnborg default "6" if X86_64 1509506f1d07SSam Ravnborg default "3" 1510506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15118f9ca475SIngo Molnar ---help--- 15121184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1513692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1514506f1d07SSam Ravnborg 1515506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15163c2362e6SHarvey Harrison def_bool y 1517506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1518506f1d07SSam Ravnborg 1519506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 15203c2362e6SHarvey Harrison def_bool y 1521506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1522506f1d07SSam Ravnborg 1523506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1524506f1d07SSam Ravnborg def_bool y 15253b16651fSTejun Heo depends on X86_32 && !NUMA 1526506f1d07SSam Ravnborg 1527506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1528506f1d07SSam Ravnborg def_bool y 1529b263295dSChristoph Lameter depends on NUMA && X86_32 1530506f1d07SSam Ravnborg 1531506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1532506f1d07SSam Ravnborg def_bool y 1533b263295dSChristoph Lameter depends on NUMA && X86_32 1534b263295dSChristoph Lameter 1535506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1536506f1d07SSam Ravnborg def_bool y 15376ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1538506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1539506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1540506f1d07SSam Ravnborg 15413b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 15423b16651fSTejun Heo def_bool y 15433b16651fSTejun Heo depends on X86_64 15443b16651fSTejun Heo 1545506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1546506f1d07SSam Ravnborg def_bool y 1547b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1548506f1d07SSam Ravnborg 1549506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1550a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 15513120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1552a0842b70SToshi Kani help 1553a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1554a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1555a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1556506f1d07SSam Ravnborg 15573b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 15583b16651fSTejun Heo def_bool y 15593b16651fSTejun Heo depends on X86_64 && PROC_KCORE 15603b16651fSTejun Heo 1561a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1562a29815a3SAvi Kivity hex 1563a29815a3SAvi Kivity default 0 if X86_32 1564a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1565a29815a3SAvi Kivity 1566506f1d07SSam Ravnborgsource "mm/Kconfig" 1567506f1d07SSam Ravnborg 15687a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 15697a67832cSDan Williams bool 15707a67832cSDan Williams 1571ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 15727a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 15739f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 15749f53f9faSDan Williams depends on BLK_DEV 15757a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 15769f53f9faSDan Williams select LIBNVDIMM 1577ec776ef6SChristoph Hellwig help 1578ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1579ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1580ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1581ec776ef6SChristoph Hellwig they can be used for persistent storage. 1582ec776ef6SChristoph Hellwig 1583ec776ef6SChristoph Hellwig Say Y if unsure. 1584ec776ef6SChristoph Hellwig 1585506f1d07SSam Ravnborgconfig HIGHPTE 1586506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 15876fc108a0SJan Beulich depends on HIGHMEM 15888f9ca475SIngo Molnar ---help--- 1589506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1590506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1591506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1592506f1d07SSam Ravnborg entries in high memory. 1593506f1d07SSam Ravnborg 15949f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 15959f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 15968f9ca475SIngo Molnar ---help--- 15979f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 15989f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 15999f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16009f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16019f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16029f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16039f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16048c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16059f077871SJeremy Fitzhardinge 16069f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16079f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16089f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16099f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16109f077871SJeremy Fitzhardinge 16119f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16129f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16139f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16149f077871SJeremy Fitzhardinge memory. 16159f077871SJeremy Fitzhardinge 1616c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1617c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1618c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1619c885df50SJeremy Fitzhardinge default y 16208f9ca475SIngo Molnar ---help--- 1621c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1622c885df50SJeremy Fitzhardinge on or off. 1623c885df50SJeremy Fitzhardinge 16249ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1625d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1626d0cd7425SH. Peter Anvin default 64 1627d0cd7425SH. Peter Anvin range 4 640 16288f9ca475SIngo Molnar ---help--- 1629d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1630fc381519SIngo Molnar 1631d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1632d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1633fc381519SIngo Molnar 1634d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1635d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1636d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1637d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1638fc381519SIngo Molnar 1639d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1640d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1641d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1642d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1643d0cd7425SH. Peter Anvin entire low memory range. 1644d0cd7425SH. Peter Anvin 1645d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1646d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1647d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1648d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1649d0cd7425SH. Peter Anvin typical corruption patterns. 1650d0cd7425SH. Peter Anvin 1651d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1652fc381519SIngo Molnar 1653506f1d07SSam Ravnborgconfig MATH_EMULATION 1654506f1d07SSam Ravnborg bool 1655a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1656506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1657506f1d07SSam Ravnborg ---help--- 1658506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1659506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1660506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1661506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1662506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1663506f1d07SSam Ravnborg coprocessor or this emulation. 1664506f1d07SSam Ravnborg 1665506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1666506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1667506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1668506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1669506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1670506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1671506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1672506f1d07SSam Ravnborg intend to use this kernel on different machines. 1673506f1d07SSam Ravnborg 1674506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1675506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1676506f1d07SSam Ravnborg 1677506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1678506f1d07SSam Ravnborg kernel, it won't hurt. 1679506f1d07SSam Ravnborg 1680506f1d07SSam Ravnborgconfig MTRR 16816fc108a0SJan Beulich def_bool y 16826a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1683506f1d07SSam Ravnborg ---help--- 1684506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1685506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1686506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1687506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1688506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1689506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1690506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1691506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1692506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1693506f1d07SSam Ravnborg 1694506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1695506f1d07SSam Ravnborg control registers on other processors can be easily supported 1696506f1d07SSam Ravnborg as well: 1697506f1d07SSam Ravnborg 1698506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1699506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1700506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1701506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1702506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1703506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1704506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1705506f1d07SSam Ravnborg 1706506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1707506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1708506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1709506f1d07SSam Ravnborg 1710506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1711506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1712506f1d07SSam Ravnborg 17137225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1714506f1d07SSam Ravnborg 171595ffa243SYinghai Luconfig MTRR_SANITIZER 17162ffb3501SYinghai Lu def_bool y 171795ffa243SYinghai Lu prompt "MTRR cleanup support" 171895ffa243SYinghai Lu depends on MTRR 17198f9ca475SIngo Molnar ---help--- 1720aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1721aba3728cSThomas Gleixner add writeback entries. 172295ffa243SYinghai Lu 1723aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1724692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1725aba3728cSThomas Gleixner mtrr_chunk_size. 172695ffa243SYinghai Lu 17272ffb3501SYinghai Lu If unsure, say Y. 172895ffa243SYinghai Lu 172995ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1730f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1731f5098d62SYinghai Lu range 0 1 1732f5098d62SYinghai Lu default "0" 173395ffa243SYinghai Lu depends on MTRR_SANITIZER 17348f9ca475SIngo Molnar ---help--- 1735f5098d62SYinghai Lu Enable mtrr cleanup default value 173695ffa243SYinghai Lu 173712031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 173812031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 173912031a62SYinghai Lu range 0 7 174012031a62SYinghai Lu default "1" 174112031a62SYinghai Lu depends on MTRR_SANITIZER 17428f9ca475SIngo Molnar ---help--- 174312031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1744aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 174512031a62SYinghai Lu 17462e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 17476fc108a0SJan Beulich def_bool y 17486a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 17492a8a2719SIngo Molnar depends on MTRR 17508f9ca475SIngo Molnar ---help--- 17512e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1752042b78e4SVenki Pallipadi 17532e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 17542e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 17552e5d9c85Svenkatesh.pallipadi@intel.com 17562e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1757042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 17582e5d9c85Svenkatesh.pallipadi@intel.com 17592e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 17602e5d9c85Svenkatesh.pallipadi@intel.com 176146cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 176246cf98cdSVenkatesh Pallipadi def_bool y 176346cf98cdSVenkatesh Pallipadi depends on X86_PAT 176446cf98cdSVenkatesh Pallipadi 1765628c6246SH. Peter Anvinconfig ARCH_RANDOM 1766628c6246SH. Peter Anvin def_bool y 1767628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1768628c6246SH. Peter Anvin ---help--- 1769628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1770628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1771628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1772628c6246SH. Peter Anvin secure hardware random number generator. 1773628c6246SH. Peter Anvin 177451ae4a2dSH. Peter Anvinconfig X86_SMAP 177551ae4a2dSH. Peter Anvin def_bool y 177651ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 177751ae4a2dSH. Peter Anvin ---help--- 177851ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 177951ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 178051ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 178151ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 178251ae4a2dSH. Peter Anvin 178351ae4a2dSH. Peter Anvin If unsure, say Y. 178451ae4a2dSH. Peter Anvin 178572e9b5feSDave Hansenconfig X86_INTEL_MPX 178672e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 178772e9b5feSDave Hansen def_bool n 178872e9b5feSDave Hansen depends on CPU_SUP_INTEL 178972e9b5feSDave Hansen ---help--- 179072e9b5feSDave Hansen MPX provides hardware features that can be used in 179172e9b5feSDave Hansen conjunction with compiler-instrumented code to check 179272e9b5feSDave Hansen memory references. It is designed to detect buffer 179372e9b5feSDave Hansen overflow or underflow bugs. 179472e9b5feSDave Hansen 179572e9b5feSDave Hansen This option enables running applications which are 179672e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 179772e9b5feSDave Hansen itself inside the kernel or to protect the kernel 179872e9b5feSDave Hansen against bad memory references. 179972e9b5feSDave Hansen 180072e9b5feSDave Hansen Enabling this option will make the kernel larger: 180172e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 180272e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 180372e9b5feSDave Hansen will increase the kernel memory overhead of each 180472e9b5feSDave Hansen process and adds some branches to paths used during 180572e9b5feSDave Hansen exec() and munmap(). 180672e9b5feSDave Hansen 180772e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 180872e9b5feSDave Hansen 180972e9b5feSDave Hansen If unsure, say N. 181072e9b5feSDave Hansen 181135e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1812284244a9SDave Hansen prompt "Intel Memory Protection Keys" 181335e97790SDave Hansen def_bool y 1814284244a9SDave Hansen # Note: only available in 64-bit mode 181535e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 181652c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 181752c8e601SIngo Molnar select ARCH_HAS_PKEYS 1818284244a9SDave Hansen ---help--- 1819284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1820284244a9SDave Hansen page-based protections, but without requiring modification of the 1821284244a9SDave Hansen page tables when an application changes protection domains. 1822284244a9SDave Hansen 1823284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1824284244a9SDave Hansen 1825284244a9SDave Hansen If unsure, say y. 182635e97790SDave Hansen 1827506f1d07SSam Ravnborgconfig EFI 18289ba16087SJan Beulich bool "EFI runtime service support" 18295b83683fSHuang, Ying depends on ACPI 1830f6ce5002SSergey Vlasov select UCS2_STRING 1831022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1832506f1d07SSam Ravnborg ---help--- 18338b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1834506f1d07SSam Ravnborg available (such as the EFI variable services). 1835506f1d07SSam Ravnborg 18368b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 18378b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 18388b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 18398b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 18408b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 18418b2cb7a8SHuang, Ying platforms. 1842506f1d07SSam Ravnborg 1843291f3632SMatt Flemingconfig EFI_STUB 1844291f3632SMatt Fleming bool "EFI stub support" 1845b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 18467b2a583aSMatt Fleming select RELOCATABLE 1847291f3632SMatt Fleming ---help--- 1848291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1849291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1850291f3632SMatt Fleming 18514172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 18520c759662SMatt Fleming 18537d453eeeSMatt Flemingconfig EFI_MIXED 18547d453eeeSMatt Fleming bool "EFI mixed-mode support" 18557d453eeeSMatt Fleming depends on EFI_STUB && X86_64 18567d453eeeSMatt Fleming ---help--- 18577d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 18587d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 18597d453eeeSMatt Fleming mode. 18607d453eeeSMatt Fleming 18617d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 18627d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 18637d453eeeSMatt Fleming the EFI handover protocol must be used. 18647d453eeeSMatt Fleming 18657d453eeeSMatt Fleming If unsure, say N. 18667d453eeeSMatt Fleming 1867506f1d07SSam Ravnborgconfig SECCOMP 18683c2362e6SHarvey Harrison def_bool y 18693c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 18708f9ca475SIngo Molnar ---help--- 1871506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1872506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1873506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1874506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1875506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1876506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 18779c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1878506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1879506f1d07SSam Ravnborg defined by each seccomp mode. 1880506f1d07SSam Ravnborg 1881506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1882506f1d07SSam Ravnborg 1883506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1884506f1d07SSam Ravnborg 1885506f1d07SSam Ravnborgconfig KEXEC 1886506f1d07SSam Ravnborg bool "kexec system call" 18872965faa5SDave Young select KEXEC_CORE 18888f9ca475SIngo Molnar ---help--- 1889506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1890506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1891506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1892506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1893506f1d07SSam Ravnborg 1894506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1895506f1d07SSam Ravnborg 1896506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1897506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1898bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1899bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1900bf220695SGeert Uytterhoeven made. 1901506f1d07SSam Ravnborg 190274ca317cSVivek Goyalconfig KEXEC_FILE 190374ca317cSVivek Goyal bool "kexec file based system call" 19042965faa5SDave Young select KEXEC_CORE 190574ca317cSVivek Goyal select BUILD_BIN2C 190674ca317cSVivek Goyal depends on X86_64 190774ca317cSVivek Goyal depends on CRYPTO=y 190874ca317cSVivek Goyal depends on CRYPTO_SHA256=y 190974ca317cSVivek Goyal ---help--- 191074ca317cSVivek Goyal This is new version of kexec system call. This system call is 191174ca317cSVivek Goyal file based and takes file descriptors as system call argument 191274ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 191374ca317cSVivek Goyal accepted by previous system call. 191474ca317cSVivek Goyal 19158e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 19168e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 191774ca317cSVivek Goyal depends on KEXEC_FILE 19188e7d8381SVivek Goyal ---help--- 19198e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1920d8eb8940SBorislav Petkov the kexec_file_load() syscall. 19218e7d8381SVivek Goyal 1922d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1923d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1924d8eb8940SBorislav Petkov loaded in order for this to work. 19258e7d8381SVivek Goyal 19268e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 19278e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 19288e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 19298e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 19308e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 19318e7d8381SVivek Goyal ---help--- 19328e7d8381SVivek Goyal Enable bzImage signature verification support. 19338e7d8381SVivek Goyal 1934506f1d07SSam Ravnborgconfig CRASH_DUMP 193504b69447SPavel Machek bool "kernel crash dumps" 1936506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 19378f9ca475SIngo Molnar ---help--- 1938506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1939506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1940506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1941506f1d07SSam Ravnborg a specially reserved region and then later executed after 1942506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1943506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1944506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1945506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1946506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1947506f1d07SSam Ravnborg 19483ab83521SHuang Yingconfig KEXEC_JUMP 19496ea30386SKees Cook bool "kexec jump" 1950fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 19518f9ca475SIngo Molnar ---help--- 195289081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 195389081d17SHuang Ying code in physical address mode via KEXEC 19543ab83521SHuang Ying 1955506f1d07SSam Ravnborgconfig PHYSICAL_START 19566a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1957ceefccc9SH. Peter Anvin default "0x1000000" 19588f9ca475SIngo Molnar ---help--- 1959506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1960506f1d07SSam Ravnborg 1961506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1962506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1963506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1964506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1965506f1d07SSam Ravnborg address. 1966506f1d07SSam Ravnborg 1967506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1968506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1969506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1970506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1971506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1972506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1973506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1974506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1975506f1d07SSam Ravnborg 1976ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 1977ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 1978ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1979ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 1980ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 1981ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 1982ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 1983ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 1984ceefccc9SH. Peter Anvin for more details about crash dumps. 1985506f1d07SSam Ravnborg 1986506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 1987506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 1988506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 1989506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 1990506f1d07SSam Ravnborg is present because there are users out there who continue to use 1991506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 1992506f1d07SSam Ravnborg line. 1993506f1d07SSam Ravnborg 1994506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1995506f1d07SSam Ravnborg 1996506f1d07SSam Ravnborgconfig RELOCATABLE 199726717808SH. Peter Anvin bool "Build a relocatable kernel" 199826717808SH. Peter Anvin default y 19998f9ca475SIngo Molnar ---help--- 2000506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2001506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2002506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2003506f1d07SSam Ravnborg but are discarded at runtime. 2004506f1d07SSam Ravnborg 2005506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2006506f1d07SSam Ravnborg must live at a different physical address than the primary 2007506f1d07SSam Ravnborg kernel. 2008506f1d07SSam Ravnborg 2009506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2010506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 20118ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2012506f1d07SSam Ravnborg 20138ab3820fSKees Cookconfig RANDOMIZE_BASE 2014e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 20158ab3820fSKees Cook depends on RELOCATABLE 20166807c846SIngo Molnar default y 20178ab3820fSKees Cook ---help--- 2018e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2019e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2020e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2021e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2022e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2023e8581e3dSBaoquan He code internals. 2024e8581e3dSBaoquan He 2025ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2026ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2027ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2028ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2029ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2030ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2031ed9f007eSKees Cook 2032ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2033ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2034ed9f007eSKees Cook 512MB (8 bits of entropy). 20358ab3820fSKees Cook 2036a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2037e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2038e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2039ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2040ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2041ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2042ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2043ed9f007eSKees Cook theoretically possible, but the implementations are further 2044ed9f007eSKees Cook limited due to memory layouts. 2045e8581e3dSBaoquan He 20466807c846SIngo Molnar If unsure, say Y. 2047da2b6fb9SKees Cook 20488ab3820fSKees Cook# Relocation on x86 needs some additional build support 2049845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2050845adf72SH. Peter Anvin def_bool y 20518ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2052845adf72SH. Peter Anvin 2053506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2054a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 20558ab3820fSKees Cook default "0x200000" 2056a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2057a0215061SKees Cook range 0x200000 0x1000000 if X86_64 20588f9ca475SIngo Molnar ---help--- 2059506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2060506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2061506f1d07SSam Ravnborg address which meets above alignment restriction. 2062506f1d07SSam Ravnborg 2063506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2064506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2065506f1d07SSam Ravnborg address aligned to above value and run from there. 2066506f1d07SSam Ravnborg 2067506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2068506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2069506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2070506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2071506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2072506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2073506f1d07SSam Ravnborg above alignment restrictions. 2074506f1d07SSam Ravnborg 2075a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2076a0215061SKees Cook this value must be a multiple of 0x200000. 2077a0215061SKees Cook 2078506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2079506f1d07SSam Ravnborg 20800483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 20810483e1faSThomas Garnier bool "Randomize the kernel memory sections" 20820483e1faSThomas Garnier depends on X86_64 20830483e1faSThomas Garnier depends on RANDOMIZE_BASE 20840483e1faSThomas Garnier default RANDOMIZE_BASE 20850483e1faSThomas Garnier ---help--- 20860483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 20870483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 20880483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 20890483e1faSThomas Garnier 20900483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 20910483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 20920483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 20930483e1faSThomas Garnier addresses for each memory section. 20940483e1faSThomas Garnier 20956807c846SIngo Molnar If unsure, say Y. 20960483e1faSThomas Garnier 209790397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 209890397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 209990397a41SThomas Garnier depends on RANDOMIZE_MEMORY 210090397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 210190397a41SThomas Garnier default "0x0" 210290397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 210390397a41SThomas Garnier range 0x0 0x40 210490397a41SThomas Garnier ---help--- 210590397a41SThomas Garnier Define the padding in terabytes added to the existing physical 210690397a41SThomas Garnier memory size during kernel memory randomization. It is useful 210790397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 210890397a41SThomas Garnier address randomization. 210990397a41SThomas Garnier 211090397a41SThomas Garnier If unsure, leave at the default value. 211190397a41SThomas Garnier 2112506f1d07SSam Ravnborgconfig HOTPLUG_CPU 21137c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 211440b31360SStephen Rothwell depends on SMP 2115506f1d07SSam Ravnborg ---help--- 21167c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 21177c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 21187c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 21197c13e6a3SDimitri Sivanich automatically on SMP systems. ) 21207c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2121506f1d07SSam Ravnborg 212280aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 212380aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 212480aa1dffSFenghua Yu default n 21252c922cd0SKees Cook depends on HOTPLUG_CPU 212680aa1dffSFenghua Yu ---help--- 212780aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 212880aa1dffSFenghua Yu 212980aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 213080aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 213180aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 213280aa1dffSFenghua Yu 213380aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 213480aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 213580aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 213680aa1dffSFenghua Yu 213780aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 213880aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 213980aa1dffSFenghua Yu 214080aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 214180aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 214280aa1dffSFenghua Yu be other CPU0 dependencies. 214380aa1dffSFenghua Yu 214480aa1dffSFenghua Yu Please make sure the dependencies are under your control before 214580aa1dffSFenghua Yu you enable this feature. 214680aa1dffSFenghua Yu 214780aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 214880aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 214980aa1dffSFenghua Yu parameter cpu0_hotplug. 215080aa1dffSFenghua Yu 2151a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2152a71c8bc5SFenghua Yu def_bool n 2153a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 21542c922cd0SKees Cook depends on HOTPLUG_CPU 2155a71c8bc5SFenghua Yu ---help--- 2156a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2157a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2158a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2159a71c8bc5SFenghua Yu 2160a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2161a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2162a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2163a71c8bc5SFenghua Yu 2164a71c8bc5SFenghua Yu If unsure, say N. 2165a71c8bc5SFenghua Yu 2166506f1d07SSam Ravnborgconfig COMPAT_VDSO 2167b0b49f26SAndy Lutomirski def_bool n 2168b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2169953fee1dSIngo Molnar depends on COMPAT_32 21708f9ca475SIngo Molnar ---help--- 2171b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2172b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2173b0b49f26SAndy Lutomirski indicated in its segment table. 2174e84446deSRandy Dunlap 2175b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2176b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2177b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2178b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2179b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2180506f1d07SSam Ravnborg 2181b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2182b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2183b0b49f26SAndy Lutomirski 2184b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2185b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2186b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2187b0b49f26SAndy Lutomirski 2188b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2189b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2190506f1d07SSam Ravnborg 21913dc33bd3SKees Cookchoice 21923dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 21933dc33bd3SKees Cook depends on X86_64 21943dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 21953dc33bd3SKees Cook help 21963dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 21973dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 21983dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 21993dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22003dc33bd3SKees Cook 22013dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 22023dc33bd3SKees Cook line parameter vsyscall=[native|emulate|none]. 22033dc33bd3SKees Cook 22043dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22053dc33bd3SKees Cook static binaries, you can say None without a performance penalty 22063dc33bd3SKees Cook to improve security. 22073dc33bd3SKees Cook 22083dc33bd3SKees Cook If unsure, select "Emulate". 22093dc33bd3SKees Cook 22103dc33bd3SKees Cook config LEGACY_VSYSCALL_NATIVE 22113dc33bd3SKees Cook bool "Native" 22123dc33bd3SKees Cook help 22133dc33bd3SKees Cook Actual executable code is located in the fixed vsyscall 22143dc33bd3SKees Cook address mapping, implementing time() efficiently. Since 22153dc33bd3SKees Cook this makes the mapping executable, it can be used during 22163dc33bd3SKees Cook security vulnerability exploitation (traditionally as 22173dc33bd3SKees Cook ROP gadgets). This configuration is not recommended. 22183dc33bd3SKees Cook 22193dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 22203dc33bd3SKees Cook bool "Emulate" 22213dc33bd3SKees Cook help 22223dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 22233dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 22243dc33bd3SKees Cook non-executable, but it still contains known contents, 22253dc33bd3SKees Cook which could be used in certain rare security vulnerability 22263dc33bd3SKees Cook exploits. This configuration is recommended when userspace 22273dc33bd3SKees Cook still uses the vsyscall area. 22283dc33bd3SKees Cook 22293dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 22303dc33bd3SKees Cook bool "None" 22313dc33bd3SKees Cook help 22323dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 22333dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 22343dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 22353dc33bd3SKees Cook will be reported to dmesg, so that either old or 22363dc33bd3SKees Cook malicious userspace programs can be identified. 22373dc33bd3SKees Cook 22383dc33bd3SKees Cookendchoice 22393dc33bd3SKees Cook 2240516cbf37STim Birdconfig CMDLINE_BOOL 2241516cbf37STim Bird bool "Built-in kernel command line" 22428f9ca475SIngo Molnar ---help--- 2243516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2244516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2245516cbf37STim Bird necessary or convenient to provide some or all of the 2246516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2247516cbf37STim Bird to not rely on the boot loader to provide them.) 2248516cbf37STim Bird 2249516cbf37STim Bird To compile command line arguments into the kernel, 2250516cbf37STim Bird set this option to 'Y', then fill in the 225169711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2252516cbf37STim Bird 2253516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2254516cbf37STim Bird should leave this option set to 'N'. 2255516cbf37STim Bird 2256516cbf37STim Birdconfig CMDLINE 2257516cbf37STim Bird string "Built-in kernel command string" 2258516cbf37STim Bird depends on CMDLINE_BOOL 2259516cbf37STim Bird default "" 22608f9ca475SIngo Molnar ---help--- 2261516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2262516cbf37STim Bird image and used at boot time. If the boot loader provides a 2263516cbf37STim Bird command line at boot time, it is appended to this string to 2264516cbf37STim Bird form the full kernel command line, when the system boots. 2265516cbf37STim Bird 2266516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2267516cbf37STim Bird change this behavior. 2268516cbf37STim Bird 2269516cbf37STim Bird In most cases, the command line (whether built-in or provided 2270516cbf37STim Bird by the boot loader) should specify the device for the root 2271516cbf37STim Bird file system. 2272516cbf37STim Bird 2273516cbf37STim Birdconfig CMDLINE_OVERRIDE 2274516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2275516cbf37STim Bird depends on CMDLINE_BOOL 22768f9ca475SIngo Molnar ---help--- 2277516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2278516cbf37STim Bird command line, and use ONLY the built-in command line. 2279516cbf37STim Bird 2280516cbf37STim Bird This is used to work around broken boot loaders. This should 2281516cbf37STim Bird be set to 'N' under normal conditions. 2282516cbf37STim Bird 2283a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2284a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2285a5b9e5a2SAndy Lutomirski default y 2286a5b9e5a2SAndy Lutomirski ---help--- 2287a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2288a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2289a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2290a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2291a5b9e5a2SAndy Lutomirski threading libraries. 2292a5b9e5a2SAndy Lutomirski 2293a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2294a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2295a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2296a5b9e5a2SAndy Lutomirski 2297a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2298a5b9e5a2SAndy Lutomirski 2299b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2300b700e7f0SSeth Jennings 2301506f1d07SSam Ravnborgendmenu 2302506f1d07SSam Ravnborg 2303506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2304506f1d07SSam Ravnborg def_bool y 2305506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2306506f1d07SSam Ravnborg 230735551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 230835551053SGary Hade def_bool y 230935551053SGary Hade depends on MEMORY_HOTPLUG 231035551053SGary Hade 2311e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2312645a7919STejun Heo def_bool y 2313e534c7c5SLee Schermerhorn depends on NUMA 2314e534c7c5SLee Schermerhorn 23159491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 23169491846fSKirill A. Shutemov def_bool y 23179491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 23189491846fSKirill A. Shutemov 2319c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2320c177c81eSNaoya Horiguchi def_bool y 2321c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2322c177c81eSNaoya Horiguchi 2323da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2324e279b6c1SSam Ravnborg 2325e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 23263c2362e6SHarvey Harrison def_bool y 2327e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2328e279b6c1SSam Ravnborg 2329e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2330e279b6c1SSam Ravnborg 2331e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2332e279b6c1SSam Ravnborg 2333efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2334efafc8b2SFeng Tang 2335a6b68076SAndi Kleenconfig X86_APM_BOOT 23366fc108a0SJan Beulich def_bool y 2337282e5aabSPaul Bolle depends on APM 2338a6b68076SAndi Kleen 2339e279b6c1SSam Ravnborgmenuconfig APM 2340e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2341efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2342e279b6c1SSam Ravnborg ---help--- 2343e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2344e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2345e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2346e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2347e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2348e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2349e279b6c1SSam Ravnborg 2350e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2351e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2352e279b6c1SSam Ravnborg 2353e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2354e279b6c1SSam Ravnborg machines with more than one CPU. 2355e279b6c1SSam Ravnborg 2356e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 23572dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 23582dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2359e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2360e279b6c1SSam Ravnborg 2361e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2362e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2363e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2364e279b6c1SSam Ravnborg 2365e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2366e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2367e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2368e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2369e279b6c1SSam Ravnborg 2370e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2371e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2372e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2373e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2374e279b6c1SSam Ravnborg APM in your BIOS). 2375e279b6c1SSam Ravnborg 2376e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2377e279b6c1SSam Ravnborg "weird" problems: 2378e279b6c1SSam Ravnborg 2379e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2380e279b6c1SSam Ravnborg enabled. 2381e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2382e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2383e279b6c1SSam Ravnborg the "no387" option to the kernel 2384e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2385e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2386e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2387e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2388e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2389e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2390e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2391e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2392e279b6c1SSam Ravnborg 11) exchange RAM chips 2393e279b6c1SSam Ravnborg 12) exchange the motherboard. 2394e279b6c1SSam Ravnborg 2395e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2396e279b6c1SSam Ravnborg module will be called apm. 2397e279b6c1SSam Ravnborg 2398e279b6c1SSam Ravnborgif APM 2399e279b6c1SSam Ravnborg 2400e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2401e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 24028f9ca475SIngo Molnar ---help--- 2403e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2404e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2405e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2406e279b6c1SSam Ravnborg 2407e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2408e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2409e279b6c1SSam Ravnborg ---help--- 2410e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2411e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2412e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2413e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2414e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2415e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2416e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2417e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2418e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2419e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2420e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2421e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2422e279b6c1SSam Ravnborg this feature. 2423e279b6c1SSam Ravnborg 2424e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2425dd8af076SLen Brown depends on CPU_IDLE 2426e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 24278f9ca475SIngo Molnar ---help--- 2428e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2429e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2430e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2431e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2432e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2433e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2434e279b6c1SSam Ravnborg this option does nothing.) 2435e279b6c1SSam Ravnborg 2436e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2437e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 24388f9ca475SIngo Molnar ---help--- 2439e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2440e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2441e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2442e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2443e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2444e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2445e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2446e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2447e279b6c1SSam Ravnborg especially if you are using gpm. 2448e279b6c1SSam Ravnborg 2449e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2450e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 24518f9ca475SIngo Molnar ---help--- 2452e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2453e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2454e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2455e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2456e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2457e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2458e279b6c1SSam Ravnborg 2459e279b6c1SSam Ravnborgendif # APM 2460e279b6c1SSam Ravnborg 2461bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2462e279b6c1SSam Ravnborg 2463e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2464e279b6c1SSam Ravnborg 246527471fdbSAndy Henroidsource "drivers/idle/Kconfig" 246627471fdbSAndy Henroid 2467e279b6c1SSam Ravnborgendmenu 2468e279b6c1SSam Ravnborg 2469e279b6c1SSam Ravnborg 2470e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2471e279b6c1SSam Ravnborg 2472e279b6c1SSam Ravnborgconfig PCI 24731ac97018SIngo Molnar bool "PCI support" 24741c858087SAdrian Bunk default y 24758f9ca475SIngo Molnar ---help--- 2476e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2477e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2478e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2479e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2480e279b6c1SSam Ravnborg 2481e279b6c1SSam Ravnborgchoice 2482e279b6c1SSam Ravnborg prompt "PCI access mode" 2483efefa6f6SIngo Molnar depends on X86_32 && PCI 2484e279b6c1SSam Ravnborg default PCI_GOANY 2485e279b6c1SSam Ravnborg ---help--- 2486e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2487e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2488e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2489e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2490e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2491e279b6c1SSam Ravnborg 2492e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2493e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2494e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2495e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2496e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2497e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2498e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2499e279b6c1SSam Ravnborg 2500e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2501e279b6c1SSam Ravnborg bool "BIOS" 2502e279b6c1SSam Ravnborg 2503e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2504e279b6c1SSam Ravnborg bool "MMConfig" 2505e279b6c1SSam Ravnborg 2506e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2507e279b6c1SSam Ravnborg bool "Direct" 2508e279b6c1SSam Ravnborg 25093ef0e1f8SAndres Salomonconfig PCI_GOOLPC 251076fb6570SDaniel Drake bool "OLPC XO-1" 25113ef0e1f8SAndres Salomon depends on OLPC 25123ef0e1f8SAndres Salomon 25132bdd1b03SAndres Salomonconfig PCI_GOANY 25142bdd1b03SAndres Salomon bool "Any" 25152bdd1b03SAndres Salomon 2516e279b6c1SSam Ravnborgendchoice 2517e279b6c1SSam Ravnborg 2518e279b6c1SSam Ravnborgconfig PCI_BIOS 25193c2362e6SHarvey Harrison def_bool y 2520efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2521e279b6c1SSam Ravnborg 2522e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2523e279b6c1SSam Ravnborgconfig PCI_DIRECT 25243c2362e6SHarvey Harrison def_bool y 25250aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2526e279b6c1SSam Ravnborg 2527e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 25283c2362e6SHarvey Harrison def_bool y 25295f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2530e279b6c1SSam Ravnborg 25313ef0e1f8SAndres Salomonconfig PCI_OLPC 25322bdd1b03SAndres Salomon def_bool y 25332bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 25343ef0e1f8SAndres Salomon 2535b5401a96SAlex Nixonconfig PCI_XEN 2536b5401a96SAlex Nixon def_bool y 2537b5401a96SAlex Nixon depends on PCI && XEN 2538b5401a96SAlex Nixon select SWIOTLB_XEN 2539b5401a96SAlex Nixon 2540e279b6c1SSam Ravnborgconfig PCI_DOMAINS 25413c2362e6SHarvey Harrison def_bool y 2542e279b6c1SSam Ravnborg depends on PCI 2543e279b6c1SSam Ravnborg 2544e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2545e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2546e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2547e279b6c1SSam Ravnborg 25483f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 25496a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 25506ea30386SKees Cook depends on PCI 25513f6ea84aSIra W. Snyder help 25523f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 25533f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 25543f6ea84aSIra W. Snyder not have ACPI. 25553f6ea84aSIra W. Snyder 255664a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 255764a5fed6SBjorn Helgaas is known to be incomplete. 255864a5fed6SBjorn Helgaas 255964a5fed6SBjorn Helgaas You should say N unless you know you need this. 256064a5fed6SBjorn Helgaas 2561e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2562e279b6c1SSam Ravnborg 25633a495511SWilliam Breathitt Grayconfig ISA_BUS 25643a495511SWilliam Breathitt Gray bool "ISA-style bus support on modern systems" if EXPERT 25653a495511SWilliam Breathitt Gray select ISA_BUS_API 25663a495511SWilliam Breathitt Gray help 25673a495511SWilliam Breathitt Gray Enables ISA-style drivers on modern systems. This is necessary to 25683a495511SWilliam Breathitt Gray support PC/104 devices on X86_64 platforms. 25693a495511SWilliam Breathitt Gray 25703a495511SWilliam Breathitt Gray If unsure, say N. 25713a495511SWilliam Breathitt Gray 25721c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2573e279b6c1SSam Ravnborgconfig ISA_DMA_API 25741c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 25751c00f016SDavid Rientjes default y 25761c00f016SDavid Rientjes help 25771c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 25781c00f016SDavid Rientjes If unsure, say Y. 2579e279b6c1SSam Ravnborg 258051e68d05SLinus Torvaldsif X86_32 258151e68d05SLinus Torvalds 2582e279b6c1SSam Ravnborgconfig ISA 2583e279b6c1SSam Ravnborg bool "ISA support" 25848f9ca475SIngo Molnar ---help--- 2585e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2586e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2587e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2588e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2589e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2590e279b6c1SSam Ravnborg 2591e279b6c1SSam Ravnborgconfig EISA 2592e279b6c1SSam Ravnborg bool "EISA support" 2593e279b6c1SSam Ravnborg depends on ISA 2594e279b6c1SSam Ravnborg ---help--- 2595e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2596e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2597e279b6c1SSam Ravnborg 2598e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2599e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2600e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2601e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2602e279b6c1SSam Ravnborg 2603e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2604e279b6c1SSam Ravnborg 2605e279b6c1SSam Ravnborg Otherwise, say N. 2606e279b6c1SSam Ravnborg 2607e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2608e279b6c1SSam Ravnborg 2609e279b6c1SSam Ravnborgconfig SCx200 2610e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26118f9ca475SIngo Molnar ---help--- 2612e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2613e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2614e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2615e279b6c1SSam Ravnborg for other scx200_* drivers. 2616e279b6c1SSam Ravnborg 2617e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2618e279b6c1SSam Ravnborg 2619e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2620e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2621592913ecSJohn Stultz depends on SCx200 2622e279b6c1SSam Ravnborg default y 26238f9ca475SIngo Molnar ---help--- 2624e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2625e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2626e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2627e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2628e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2629e279b6c1SSam Ravnborg 26303ef0e1f8SAndres Salomonconfig OLPC 26313ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 263254008979SThomas Gleixner depends on !X86_PAE 26333c554946SAndres Salomon select GPIOLIB 2634dc3119e7SThomas Gleixner select OF 263545bb1674SDaniel Drake select OF_PROMTREE 2636b4e51854SGrant Likely select IRQ_DOMAIN 26378f9ca475SIngo Molnar ---help--- 26383ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 26393ef0e1f8SAndres Salomon XO hardware. 26403ef0e1f8SAndres Salomon 2641a3128588SDaniel Drakeconfig OLPC_XO1_PM 2642a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 264397c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2644a3128588SDaniel Drake select MFD_CORE 2645bf1ebf00SDaniel Drake ---help--- 264697c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2647bf1ebf00SDaniel Drake 2648cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2649cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2650cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2651cfee9597SDaniel Drake ---help--- 2652cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2653cfee9597SDaniel Drake programmable wakeup source. 2654cfee9597SDaniel Drake 26557feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 26567feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2657d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2658ed8e47feSRandy Dunlap depends on INPUT=y 2659d8d01a63SDaniel Drake select POWER_SUPPLY 26607feda8e9SDaniel Drake select GPIO_CS5535 26617feda8e9SDaniel Drake select MFD_CORE 26627feda8e9SDaniel Drake ---help--- 26637feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 26647bc74b3dSDaniel Drake - EC-driven system wakeups 26657feda8e9SDaniel Drake - Power button 26667bc74b3dSDaniel Drake - Ebook switch 26672cf2baeaSDaniel Drake - Lid switch 2668e1040ac6SDaniel Drake - AC adapter status updates 2669e1040ac6SDaniel Drake - Battery status updates 26707feda8e9SDaniel Drake 2671a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2672a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2673d8d01a63SDaniel Drake depends on OLPC && ACPI 2674d8d01a63SDaniel Drake select POWER_SUPPLY 2675a0f30f59SDaniel Drake ---help--- 2676a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2677a0f30f59SDaniel Drake - EC-driven system wakeups 2678a0f30f59SDaniel Drake - AC adapter status updates 2679a0f30f59SDaniel Drake - Battery status updates 2680e279b6c1SSam Ravnborg 2681d4f3e350SEd Wildgooseconfig ALIX 2682d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2683d4f3e350SEd Wildgoose select GPIOLIB 2684d4f3e350SEd Wildgoose ---help--- 2685d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2686d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2687d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2688d4f3e350SEd Wildgoose get added here. 2689d4f3e350SEd Wildgoose 2690d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2691d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2692d4f3e350SEd Wildgoose 2693d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2694d4f3e350SEd Wildgoose 2695da4e3302SPhilip Prindevilleconfig NET5501 2696da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2697da4e3302SPhilip Prindeville select GPIOLIB 2698da4e3302SPhilip Prindeville ---help--- 2699da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2700da4e3302SPhilip Prindeville 27013197059aSPhilip A. Prindevilleconfig GEOS 27023197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27033197059aSPhilip A. Prindeville select GPIOLIB 27043197059aSPhilip A. Prindeville depends on DMI 27053197059aSPhilip A. Prindeville ---help--- 27063197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27073197059aSPhilip A. Prindeville 27087d029125SVivien Didelotconfig TS5500 27097d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27107d029125SVivien Didelot depends on MELAN 27117d029125SVivien Didelot select CHECK_SIGNATURE 27127d029125SVivien Didelot select NEW_LEDS 27137d029125SVivien Didelot select LEDS_CLASS 27147d029125SVivien Didelot ---help--- 27157d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27167d029125SVivien Didelot 2717e279b6c1SSam Ravnborgendif # X86_32 2718e279b6c1SSam Ravnborg 271923ac4ae8SAndreas Herrmannconfig AMD_NB 2720e279b6c1SSam Ravnborg def_bool y 27210e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2722e279b6c1SSam Ravnborg 2723e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2724e279b6c1SSam Ravnborg 2725388b78adSAlexandre Bounineconfig RAPIDIO 2726fdf90abcSAlexandre Bounine tristate "RapidIO support" 2727388b78adSAlexandre Bounine depends on PCI 2728388b78adSAlexandre Bounine default n 2729388b78adSAlexandre Bounine help 2730fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2731388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2732388b78adSAlexandre Bounine 2733388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2734388b78adSAlexandre Bounine 2735e3263ab3SDavid Herrmannconfig X86_SYSFB 2736e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2737e3263ab3SDavid Herrmann help 2738e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2739e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2740e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2741e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2742e3263ab3SDavid Herrmann to x86. 2743e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2744e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2745e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2746e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2747e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2748e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2749e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2750e3263ab3SDavid Herrmann 2751e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2752e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2753e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2754e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2755e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2756e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2757e3263ab3SDavid Herrmann incompatible with simplefb. 2758e3263ab3SDavid Herrmann 2759e3263ab3SDavid Herrmann If unsure, say Y. 2760e3263ab3SDavid Herrmann 2761e279b6c1SSam Ravnborgendmenu 2762e279b6c1SSam Ravnborg 2763e279b6c1SSam Ravnborg 2764e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2765e279b6c1SSam Ravnborg 2766e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2767e279b6c1SSam Ravnborg 2768e279b6c1SSam Ravnborgconfig IA32_EMULATION 2769e279b6c1SSam Ravnborg bool "IA32 Emulation" 2770e279b6c1SSam Ravnborg depends on X86_64 277139f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2772d1603990SRandy Dunlap select BINFMT_ELF 2773a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 277439f88911SIngo Molnar select COMPAT_OLD_SIGACTION 27758f9ca475SIngo Molnar ---help--- 27765fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 27775fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 27785fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2779e279b6c1SSam Ravnborg 2780e279b6c1SSam Ravnborgconfig IA32_AOUT 2781e279b6c1SSam Ravnborg tristate "IA32 a.out support" 27826b213e1bSDavid Woodhouse depends on IA32_EMULATION 27838f9ca475SIngo Molnar ---help--- 2784e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2785e279b6c1SSam Ravnborg 27860bf62763SH. Peter Anvinconfig X86_X32 27876ea30386SKees Cook bool "x32 ABI for 64-bit mode" 27889b54050bSBrian Gerst depends on X86_64 27895fd92e65SH. J. Lu ---help--- 27905fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 27915fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 27925fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 27935fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 27945fd92e65SH. J. Lu 27955fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 27965fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 27975fd92e65SH. J. Lu option set. 27985fd92e65SH. J. Lu 2799953fee1dSIngo Molnarconfig COMPAT_32 2800953fee1dSIngo Molnar def_bool y 2801953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2802953fee1dSIngo Molnar select HAVE_UID16 2803953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2804953fee1dSIngo Molnar 2805e279b6c1SSam Ravnborgconfig COMPAT 28063c2362e6SHarvey Harrison def_bool y 28070bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2808e279b6c1SSam Ravnborg 28093120e25eSJan Beulichif COMPAT 2810e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28113120e25eSJan Beulich def_bool y 2812e279b6c1SSam Ravnborg 2813e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28143c2362e6SHarvey Harrison def_bool y 28153120e25eSJan Beulich depends on SYSVIPC 28163120e25eSJan Beulichendif 2817ee009e4aSDavid Howells 2818e279b6c1SSam Ravnborgendmenu 2819e279b6c1SSam Ravnborg 2820e279b6c1SSam Ravnborg 2821e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2822e5beae16SKeith Packard def_bool y 2823e5beae16SKeith Packard depends on X86_32 2824e5beae16SKeith Packard 28254692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28264692d77fSAlessandro Rubini bool 282783125a3aSAlessandro Rubini depends on X86_64 || STA2X11 28284692d77fSAlessandro Rubini 2829f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2830f7219a53SAlessandro Rubini bool 283183125a3aSAlessandro Rubini depends on STA2X11 2832f7219a53SAlessandro Rubini 2833e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2834e585513bSKirill A. Shutemov def_bool y 2835e585513bSKirill A. Shutemov 2836e279b6c1SSam Ravnborgsource "net/Kconfig" 2837e279b6c1SSam Ravnborg 2838e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2839e279b6c1SSam Ravnborg 2840e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2841e279b6c1SSam Ravnborg 2842e279b6c1SSam Ravnborgsource "fs/Kconfig" 2843e279b6c1SSam Ravnborg 2844e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2845e279b6c1SSam Ravnborg 2846e279b6c1SSam Ravnborgsource "security/Kconfig" 2847e279b6c1SSam Ravnborg 2848e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2849e279b6c1SSam Ravnborg 2850edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2851edf88417SAvi Kivity 2852e279b6c1SSam Ravnborgsource "lib/Kconfig" 2853