1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 2daa93fabSSam Ravnborg# Select 32 or 64 bit 3daa93fabSSam Ravnborgconfig 64BIT 46840999bSSam Ravnborg bool "64-bit kernel" if ARCH = "x86" 5ffee0de4SDavid Woodhouse default ARCH != "i386" 68f9ca475SIngo Molnar ---help--- 7daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 8daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 9daa93fabSSam Ravnborg 10daa93fabSSam Ravnborgconfig X86_32 113120e25eSJan Beulich def_bool y 123120e25eSJan Beulich depends on !64BIT 13341c787eSIngo Molnar # Options that are inherently 32-bit kernel only: 14341c787eSIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION 15341c787eSIngo Molnar select CLKSRC_I8253 16341c787eSIngo Molnar select CLONE_BACKWARDS 17341c787eSIngo Molnar select HAVE_AOUT 18341c787eSIngo Molnar select HAVE_GENERIC_DMA_COHERENT 19341c787eSIngo Molnar select MODULES_USE_ELF_REL 20341c787eSIngo Molnar select OLD_SIGACTION 21daa93fabSSam Ravnborg 22daa93fabSSam Ravnborgconfig X86_64 233120e25eSJan Beulich def_bool y 243120e25eSJan Beulich depends on 64BIT 25d94e0685SIngo Molnar # Options that are inherently 64-bit kernel only: 26e1073d1eSAneesh Kumar K.V select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA 27d94e0685SIngo Molnar select ARCH_SUPPORTS_INT128 28d94e0685SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF 29d94e0685SIngo Molnar select HAVE_ARCH_SOFT_DIRTY 30d94e0685SIngo Molnar select MODULES_USE_ELF_RELA 31d94e0685SIngo Molnar select X86_DEV_DMA_OPS 321032c0baSSam Ravnborg 33d94e0685SIngo Molnar# 34d94e0685SIngo Molnar# Arch settings 35d94e0685SIngo Molnar# 36d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 37d94e0685SIngo Molnar# ported to 32-bit as well. ) 38d94e0685SIngo Molnar# 398d5fffb9SSam Ravnborgconfig X86 403c2362e6SHarvey Harrison def_bool y 41c763ea26SIngo Molnar # 42c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 43c763ea26SIngo Molnar # 446471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 456e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 466471b825SIngo Molnar select ANON_INODES 476471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 486471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 4991dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 50fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5121266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 526471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5372d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 546974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 55957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 565c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 57ea8c64acSChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 5810bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 59c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 6039208aa7SKees Cook select ARCH_HAS_REFCOUNT 610aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 62d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 636471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 64ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 65ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 66ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 67c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 6865f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 696471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 706471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 7177fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 725e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 736471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 746471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 756471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 766471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 776471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 78ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 79c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 8038d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 816471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 826471b825SIngo Molnar select CLKEVT_I8253 836471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 846471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 856471b825SIngo Molnar select DCACHE_WORD_ACCESS 8645471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 8745471cd9SLinus Torvalds select EDAC_SUPPORT 886471b825SIngo Molnar select GENERIC_CLOCKEVENTS 896471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 906471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 916471b825SIngo Molnar select GENERIC_CMOS_UPDATE 926471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 9361dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 946471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 956471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 966471b825SIngo Molnar select GENERIC_IOMAP 97c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 980fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 99ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1006471b825SIngo Molnar select GENERIC_IRQ_PROBE 101c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1026471b825SIngo Molnar select GENERIC_IRQ_SHOW 1036471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1046471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1056471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1066471b825SIngo Molnar select GENERIC_STRNLEN_USER 1076471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1087edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1096471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1106471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1116471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1126471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1136471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1146471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 115d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1166471b825SIngo Molnar select HAVE_ARCH_KGDB 1179e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1189e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1191b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1206471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 121f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 1226471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1236471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 124a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 125e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 126c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1276471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1286471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1296471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1306471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 131c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1326471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1336471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1346471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1356471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1369c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 137677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 13806aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 139c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 14058340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1415f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 142644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1436471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1446471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1456471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1466b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1470067f129SK.Prasad select HAVE_HW_BREAKPOINT 1486471b825SIngo Molnar select HAVE_IDE 1496471b825SIngo Molnar select HAVE_IOREMAP_PROT 1506471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1516471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1526471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1536471b825SIngo Molnar select HAVE_KERNEL_GZIP 1546471b825SIngo Molnar select HAVE_KERNEL_LZ4 1556471b825SIngo Molnar select HAVE_KERNEL_LZMA 1566471b825SIngo Molnar select HAVE_KERNEL_LZO 1576471b825SIngo Molnar select HAVE_KERNEL_XZ 1586471b825SIngo Molnar select HAVE_KPROBES 1596471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 160540adea3SMasami Hiramatsu select HAVE_FUNCTION_ERROR_INJECTION 1616471b825SIngo Molnar select HAVE_KRETPROBES 1626471b825SIngo Molnar select HAVE_KVM 1636471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1646471b825SIngo Molnar select HAVE_MEMBLOCK 1656471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1660102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 167ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 16842a0bb3fSPetr Mladek select HAVE_NMI 1696471b825SIngo Molnar select HAVE_OPROFILE 1706471b825SIngo Molnar select HAVE_OPTPROBES 1716471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1726471b825SIngo Molnar select HAVE_PERF_EVENTS 173c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 17492e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 175c5e63197SJiri Olsa select HAVE_PERF_REGS 176c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1779e52fc2bSVitaly Kuznetsov select HAVE_RCU_TABLE_FREE 1786471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 17911af8474SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION 180c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1816471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1826471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1837c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 184c0185808SThomas Gleixner select IRQ_FORCED_THREADING 185df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1866471b825SIngo Molnar select PERF_EVENTS 1873195ef59SPrarit Bhargava select RTC_LIB 188d6faca40SArnd Bergmann select RTC_MC146818_LIB 1896471b825SIngo Molnar select SPARSE_IRQ 19083fe27eaSPranith Kumar select SRCU 1916471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 19215f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1936471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1946471b825SIngo Molnar select VIRT_TO_BUS 1956471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1967d8330a5SBalbir Singh 197ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1983120e25eSJan Beulich def_bool y 1993120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 200ba7e4d13SIngo Molnar 20151b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 20251b26adaSLinus Torvalds string 20351b26adaSLinus Torvalds default "elf32-i386" if X86_32 20451b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 20551b26adaSLinus Torvalds 20673531905SSam Ravnborgconfig ARCH_DEFCONFIG 207b9b39bfbSSam Ravnborg string 20873531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 20973531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 210b9b39bfbSSam Ravnborg 2118d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2123c2362e6SHarvey Harrison def_bool y 2138d5fffb9SSam Ravnborg 2148d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2153c2362e6SHarvey Harrison def_bool y 2168d5fffb9SSam Ravnborg 2178d5fffb9SSam Ravnborgconfig MMU 2183c2362e6SHarvey Harrison def_bool y 2198d5fffb9SSam Ravnborg 2209e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2219e08f57dSDaniel Cashman default 28 if 64BIT 2229e08f57dSDaniel Cashman default 8 2239e08f57dSDaniel Cashman 2249e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2259e08f57dSDaniel Cashman default 32 if 64BIT 2269e08f57dSDaniel Cashman default 16 2279e08f57dSDaniel Cashman 2289e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2299e08f57dSDaniel Cashman default 8 2309e08f57dSDaniel Cashman 2319e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2329e08f57dSDaniel Cashman default 16 2339e08f57dSDaniel Cashman 2348d5fffb9SSam Ravnborgconfig SBUS 2358d5fffb9SSam Ravnborg bool 2368d5fffb9SSam Ravnborg 2373bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2383120e25eSJan Beulich def_bool y 239a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2403bc4e459SFUJITA Tomonori 24118e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2424a14d84eSAndrew Morton def_bool y 24318e98307SFUJITA Tomonori 2448d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2453120e25eSJan Beulich def_bool y 2463120e25eSJan Beulich depends on ISA_DMA_API 2478d5fffb9SSam Ravnborg 2488d5fffb9SSam Ravnborgconfig GENERIC_BUG 2493c2362e6SHarvey Harrison def_bool y 2508d5fffb9SSam Ravnborg depends on BUG 251b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 252b93a531eSJan Beulich 253b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 254b93a531eSJan Beulich bool 2558d5fffb9SSam Ravnborg 2568d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2573c2362e6SHarvey Harrison def_bool y 2588d5fffb9SSam Ravnborg 2598d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2603120e25eSJan Beulich def_bool y 2613120e25eSJan Beulich depends on ISA_DMA_API 2628d5fffb9SSam Ravnborg 2631032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2643120e25eSJan Beulich def_bool y 2651032c0baSSam Ravnborg 2661032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2671032c0baSSam Ravnborg def_bool y 2681032c0baSSam Ravnborg 2699a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2709a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2718d5fffb9SSam Ravnborg 2721b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2731b27d05bSPekka Enberg def_bool y 2741b27d05bSPekka Enberg 275dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 27689c9c4c5SBrian Gerst def_bool y 277b32ef636Stravis@sgi.com 27808fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 27908fc4580STejun Heo def_bool y 28008fc4580STejun Heo 28108fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 28211124411STejun Heo def_bool y 28311124411STejun Heo 284801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 285801e4062SJohannes Berg def_bool y 286801e4062SJohannes Berg 287f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 288f4cb5700SJohannes Berg def_bool y 289f4cb5700SJohannes Berg 290cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 291cfe28c5dSSteve Capper def_bool y 292cfe28c5dSSteve Capper 29353313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 29453313b2cSSteve Capper def_bool y 29553313b2cSSteve Capper 2968d5fffb9SSam Ravnborgconfig ZONE_DMA32 297e0fd24a3SJan Beulich def_bool y if X86_64 2988d5fffb9SSam Ravnborg 2998d5fffb9SSam Ravnborgconfig AUDIT_ARCH 300e0fd24a3SJan Beulich def_bool y if X86_64 3018d5fffb9SSam Ravnborg 302765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 303765c68bdSIngo Molnar def_bool y 304765c68bdSIngo Molnar 3056a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3066a11f75bSAkinobu Mita def_bool y 3076a11f75bSAkinobu Mita 308d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 309d6f2d75aSAndrey Ryabinin hex 310d6f2d75aSAndrey Ryabinin depends on KASAN 311d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 312d6f2d75aSAndrey Ryabinin 31369575d38SShane Wangconfig HAVE_INTEL_TXT 31469575d38SShane Wang def_bool y 3156ea30386SKees Cook depends on INTEL_IOMMU && ACPI 31669575d38SShane Wang 3176b0c3d44SSam Ravnborgconfig X86_32_SMP 3186b0c3d44SSam Ravnborg def_bool y 3196b0c3d44SSam Ravnborg depends on X86_32 && SMP 3206b0c3d44SSam Ravnborg 3216b0c3d44SSam Ravnborgconfig X86_64_SMP 3226b0c3d44SSam Ravnborg def_bool y 3236b0c3d44SSam Ravnborg depends on X86_64 && SMP 3246b0c3d44SSam Ravnborg 325ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 326ccbeed3aSTejun Heo def_bool y 3272bc2f688SKees Cook depends on X86_32 && CC_STACKPROTECTOR_NONE 328ccbeed3aSTejun Heo 3292b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3302b144498SSrikar Dronamraju def_bool y 3312b144498SSrikar Dronamraju 332d20642f0SRob Herringconfig FIX_EARLYCON_MEM 333d20642f0SRob Herring def_bool y 334d20642f0SRob Herring 33598233368SKirill A. Shutemovconfig PGTABLE_LEVELS 33698233368SKirill A. Shutemov int 33777ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 33898233368SKirill A. Shutemov default 4 if X86_64 33998233368SKirill A. Shutemov default 3 if X86_PAE 34098233368SKirill A. Shutemov default 2 34198233368SKirill A. Shutemov 342506f1d07SSam Ravnborgsource "init/Kconfig" 343dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3448d5fffb9SSam Ravnborg 345506f1d07SSam Ravnborgmenu "Processor type and features" 346506f1d07SSam Ravnborg 3475ee71535SRandy Dunlapconfig ZONE_DMA 3485ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3495ee71535SRandy Dunlap default y 3505ee71535SRandy Dunlap help 3515ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3525ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3535ee71535SRandy Dunlap Disable if no such devices will be used. 3545ee71535SRandy Dunlap 3555ee71535SRandy Dunlap If unsure, say Y. 3565ee71535SRandy Dunlap 357506f1d07SSam Ravnborgconfig SMP 358506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 359506f1d07SSam Ravnborg ---help--- 360506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3614a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3624a474157SRobert Graffham than one CPU, say Y. 363506f1d07SSam Ravnborg 3644a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 365506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 366506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3674a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 368506f1d07SSam Ravnborg will run faster if you say N here. 369506f1d07SSam Ravnborg 370506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 371506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 372506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 373506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 374506f1d07SSam Ravnborg 375506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 376506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 377506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 378506f1d07SSam Ravnborg 379395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 380c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 381506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 382506f1d07SSam Ravnborg 383506f1d07SSam Ravnborg If you don't know what to do here, say N. 384506f1d07SSam Ravnborg 3859def39beSJosh Triplettconfig X86_FEATURE_NAMES 3869def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3879def39beSJosh Triplett default y 3889def39beSJosh Triplett ---help--- 3899def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3909def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3919def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3929def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3939def39beSJosh Triplett 3949def39beSJosh Triplett If in doubt, say Y. 3959def39beSJosh Triplett 3966e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3976e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3986e1315feSBorislav Petkov default y 3996e1315feSBorislav Petkov ---help--- 4006e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 4016e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 4026e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 4036e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 4046e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 4056e1315feSBorislav Petkov slower code. 4066e1315feSBorislav Petkov 40706cd9a7dSYinghai Luconfig X86_X2APIC 40806cd9a7dSYinghai Lu bool "Support x2apic" 40919e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 41006cd9a7dSYinghai Lu ---help--- 41106cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 41206cd9a7dSYinghai Lu 41306cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 41406cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 41506cd9a7dSYinghai Lu 41606cd9a7dSYinghai Lu If you don't know what to do here, say N. 41706cd9a7dSYinghai Lu 4186695c85bSYinghai Luconfig X86_MPPARSE 4196e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4207a527688SJan Beulich default y 4215ab74722SIngo Molnar depends on X86_LOCAL_APIC 4228f9ca475SIngo Molnar ---help--- 4236695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4246695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4256695c85bSYinghai Lu 42626f7ef14SYinghai Luconfig X86_BIGSMP 42726f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 42826f7ef14SYinghai Lu depends on X86_32 && SMP 4298f9ca475SIngo Molnar ---help--- 43026f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 431506f1d07SSam Ravnborg 432ddd70cf9SJun Nakajimaconfig GOLDFISH 433ddd70cf9SJun Nakajima def_bool y 434ddd70cf9SJun Nakajima depends on X86_GOLDFISH 435ddd70cf9SJun Nakajima 43676b04384SDavid Woodhouseconfig RETPOLINE 43776b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 43876b04384SDavid Woodhouse default y 439d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 44076b04384SDavid Woodhouse help 44176b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 44276b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 44376b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 44476b04384SDavid Woodhouse support for full protection. The kernel may run slower. 44576b04384SDavid Woodhouse 44676b04384SDavid Woodhouse Without compiler support, at least indirect branches in assembler 44776b04384SDavid Woodhouse code are eliminated. Since this includes the syscall entry path, 44876b04384SDavid Woodhouse it is not entirely pointless. 44976b04384SDavid Woodhouse 450f01d7d51SVikas Shivappaconfig INTEL_RDT 451f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 45278e99b4aSFenghua Yu default n 45378e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 45459fe5a77SThomas Gleixner select KERNFS 45578e99b4aSFenghua Yu help 456f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 457f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 458f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 459f01d7d51SVikas Shivappa Architecture Software Developer Manual. 46078e99b4aSFenghua Yu 46178e99b4aSFenghua Yu Say N if unsure. 46278e99b4aSFenghua Yu 4638425091fSRavikiran G Thirumalaiif X86_32 464c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 465c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 466c5c606d9SRavikiran G Thirumalai default y 4678f9ca475SIngo Molnar ---help--- 46806ac8346SIngo Molnar If you disable this option then the kernel will only support 46906ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 47006ac8346SIngo Molnar systems out there.) 47106ac8346SIngo Molnar 4728425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4738425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 474cb7b8023SBen Hutchings Goldfish (Android emulator) 4758425091fSRavikiran G Thirumalai AMD Elan 4768425091fSRavikiran G Thirumalai RDC R-321x SoC 4778425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 47883125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4793f4110a4SThomas Gleixner Moorestown MID devices 48006ac8346SIngo Molnar 48106ac8346SIngo Molnar If you have one of these systems, or if you want to build a 48206ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4838425091fSRavikiran G Thirumalaiendif 48406ac8346SIngo Molnar 4858425091fSRavikiran G Thirumalaiif X86_64 4868425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4878425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4888425091fSRavikiran G Thirumalai default y 4898425091fSRavikiran G Thirumalai ---help--- 4908425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4918425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4928425091fSRavikiran G Thirumalai systems out there.) 4938425091fSRavikiran G Thirumalai 4948425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4958425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 49644b111b5SSteffen Persvold Numascale NumaChip 4978425091fSRavikiran G Thirumalai ScaleMP vSMP 4988425091fSRavikiran G Thirumalai SGI Ultraviolet 4998425091fSRavikiran G Thirumalai 5008425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 5018425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 5028425091fSRavikiran G Thirumalaiendif 503c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 504c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 50544b111b5SSteffen Persvoldconfig X86_NUMACHIP 50644b111b5SSteffen Persvold bool "Numascale NumaChip" 50744b111b5SSteffen Persvold depends on X86_64 50844b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 50944b111b5SSteffen Persvold depends on NUMA 51044b111b5SSteffen Persvold depends on SMP 51144b111b5SSteffen Persvold depends on X86_X2APIC 512f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 51344b111b5SSteffen Persvold ---help--- 51444b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 51544b111b5SSteffen Persvold enable more than ~168 cores. 51644b111b5SSteffen Persvold If you don't have one of these, you should say N here. 51703b48632SNick Piggin 5186a48565eSIngo Molnarconfig X86_VSMP 519c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5206276a074SBorislav Petkov select HYPERVISOR_GUEST 5216a48565eSIngo Molnar select PARAVIRT 5226a48565eSIngo Molnar depends on X86_64 && PCI 523c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 524ead91d4bSShai Fultheim depends on SMP 5258f9ca475SIngo Molnar ---help--- 5266a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5276a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5286a48565eSIngo Molnar if you have one of these machines. 5296a48565eSIngo Molnar 530c5c606d9SRavikiran G Thirumalaiconfig X86_UV 531c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 532c5c606d9SRavikiran G Thirumalai depends on X86_64 533c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 53454c28d29SJack Steiner depends on NUMA 5351ecb4ae5SAndrew Morton depends on EFI 5369d6c26e7SSuresh Siddha depends on X86_X2APIC 5371222e564SIngo Molnar depends on PCI 538c5c606d9SRavikiran G Thirumalai ---help--- 539c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 540c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 541c5c606d9SRavikiran G Thirumalai 542c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 543c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 544506f1d07SSam Ravnborg 545ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 546ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 547cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 548ddd70cf9SJun Nakajima ---help--- 549ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 550ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 551ddd70cf9SJun Nakajima Goldfish emulator say N here. 552ddd70cf9SJun Nakajima 553c751e17bSThomas Gleixnerconfig X86_INTEL_CE 554c751e17bSThomas Gleixner bool "CE4100 TV platform" 555c751e17bSThomas Gleixner depends on PCI 556c751e17bSThomas Gleixner depends on PCI_GODIRECT 5576084a6e2SJiang Liu depends on X86_IO_APIC 558c751e17bSThomas Gleixner depends on X86_32 559c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 56037bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 561da6b737bSSebastian Andrzej Siewior select OF 562da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 563c751e17bSThomas Gleixner ---help--- 564c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 565c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 566c751e17bSThomas Gleixner boxes and media devices. 567c751e17bSThomas Gleixner 5684cb9b00fSDavid Cohenconfig X86_INTEL_MID 56943605ef1SAlan Cox bool "Intel MID platform support" 57043605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 571edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5721ea7c673SAlan Cox depends on PCI 5733fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5741ea7c673SAlan Cox depends on X86_IO_APIC 5757c9c3a1eSAlan Cox select SFI 5764cb9b00fSDavid Cohen select I2C 5777c9c3a1eSAlan Cox select DW_APB_TIMER 5781ea7c673SAlan Cox select APB_TIMER 5791ea7c673SAlan Cox select INTEL_SCU_IPC 58015a713dfSMika Westerberg select MFD_INTEL_MSIC 5811ea7c673SAlan Cox ---help--- 5824cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5834cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5844cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5851ea7c673SAlan Cox 5864cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5874cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 58843605ef1SAlan Cox 5898bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5908bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5918bbc2a13SBryan O'Donoghue depends on X86_32 5928bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5938bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5948bbc2a13SBryan O'Donoghue depends on X86_TSC 5958bbc2a13SBryan O'Donoghue depends on PCI 5968bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5978bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5988bbc2a13SBryan O'Donoghue select IOSF_MBI 5998bbc2a13SBryan O'Donoghue select INTEL_IMR 6009ab6eb51SAndy Shevchenko select COMMON_CLK 6018bbc2a13SBryan O'Donoghue ---help--- 6028bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 6038bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 6048bbc2a13SBryan O'Donoghue compatible Intel Galileo. 6058bbc2a13SBryan O'Donoghue 6063d48aab1SMika Westerbergconfig X86_INTEL_LPSS 6073d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 608eebb3e8dSAndy Shevchenko depends on X86 && ACPI 6093d48aab1SMika Westerberg select COMMON_CLK 6100f531431SMathias Nyman select PINCTRL 611eebb3e8dSAndy Shevchenko select IOSF_MBI 6123d48aab1SMika Westerberg ---help--- 6133d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6143d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6150f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6160f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6173d48aab1SMika Westerberg 61892082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 61992082a88SKen Xue bool "AMD ACPI2Platform devices support" 62092082a88SKen Xue depends on ACPI 62192082a88SKen Xue select COMMON_CLK 62292082a88SKen Xue select PINCTRL 62392082a88SKen Xue ---help--- 62492082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 62592082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 62692082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 62792082a88SKen Xue implemented under PINCTRL subsystem. 62892082a88SKen Xue 629ced3ce76SDavid E. Boxconfig IOSF_MBI 630ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 631ced3ce76SDavid E. Box depends on PCI 632ced3ce76SDavid E. Box ---help--- 633ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 634ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 635ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 636ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 637ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 638ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 639ced3ce76SDavid E. Box This list is not meant to be exclusive. 640ced3ce76SDavid E. Box - BayTrail 641ced3ce76SDavid E. Box - Braswell 642ced3ce76SDavid E. Box - Quark 643ced3ce76SDavid E. Box 644ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 645ced3ce76SDavid E. Box 646ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 647ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 648ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 649ed2226bdSDavid E. Box ---help--- 650ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 651ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 652ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 653ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 654ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 655ed2226bdSDavid E. Box device they want to access. 656ed2226bdSDavid E. Box 657ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 658ed2226bdSDavid E. Box 659c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 660c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 661506f1d07SSam Ravnborg depends on X86_32 662c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 663c5c606d9SRavikiran G Thirumalai select M486 664c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 665c5c606d9SRavikiran G Thirumalai ---help--- 666c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 667c5c606d9SRavikiran G Thirumalai as R-8610-(G). 668c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 669c5c606d9SRavikiran G Thirumalai 670e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6719c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6729c398017SIngo Molnar depends on X86_32 && SMP 673c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6748f9ca475SIngo Molnar ---help--- 675b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 676b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 677b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 678b5660ba7SH. Peter Anvin one and will fallback to default. 679d49c4288SYinghai Lu 680c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 681d49c4288SYinghai Lu 682d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6836fc108a0SJan Beulich def_bool y 684d949f36fSLinus Torvalds # MCE code calls memory_failure(): 685d949f36fSLinus Torvalds depends on X86_MCE 686d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 687d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 688d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 689d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 690d949f36fSLinus Torvalds 69183125a3aSAlessandro Rubiniconfig STA2X11 69283125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 69383125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 69483125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 69583125a3aSAlessandro Rubini select X86_DMA_REMAP 69683125a3aSAlessandro Rubini select SWIOTLB 69783125a3aSAlessandro Rubini select MFD_STA2X11 6980145071bSLinus Walleij select GPIOLIB 69983125a3aSAlessandro Rubini default n 70083125a3aSAlessandro Rubini ---help--- 70183125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 70283125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 70383125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 70483125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 70583125a3aSAlessandro Rubini standard PC machines. 70683125a3aSAlessandro Rubini 70782148d1dSShérabconfig X86_32_IRIS 70882148d1dSShérab tristate "Eurobraille/Iris poweroff module" 70982148d1dSShérab depends on X86_32 71082148d1dSShérab ---help--- 71182148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 71282148d1dSShérab to shut themselves down properly. A special I/O sequence is 71382148d1dSShérab needed to do so, which is what this module does at 71482148d1dSShérab kernel shutdown. 71582148d1dSShérab 71682148d1dSShérab This is only for Iris machines from EuroBraille. 71782148d1dSShérab 71882148d1dSShérab If unused, say N. 71982148d1dSShérab 720ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7213c2362e6SHarvey Harrison def_bool y 7223c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 723a87d0914SKen Chen depends on X86 7248f9ca475SIngo Molnar ---help--- 725506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 726506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 727506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 728506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 729506f1d07SSam Ravnborg 730506f1d07SSam Ravnborg If in doubt, say "Y". 731506f1d07SSam Ravnborg 7326276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7336276a074SBorislav Petkov bool "Linux guest support" 7348f9ca475SIngo Molnar ---help--- 7356276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7366276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7376276a074SBorislav Petkov setup. 738506f1d07SSam Ravnborg 7396276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7406276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 741506f1d07SSam Ravnborg 7426276a074SBorislav Petkovif HYPERVISOR_GUEST 743506f1d07SSam Ravnborg 744e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 745e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7468f9ca475SIngo Molnar ---help--- 747e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 748e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 749e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 750e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 751e61bd94aSEduardo Pereira Habkost 7526276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7536276a074SBorislav Petkov bool "paravirt-ops debugging" 7546276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7556276a074SBorislav Petkov ---help--- 7566276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7576276a074SBorislav Petkov a paravirt_op is missing when it is called. 7586276a074SBorislav Petkov 759b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 760b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7616ea30386SKees Cook depends on PARAVIRT && SMP 762b4ecc126SJeremy Fitzhardinge ---help--- 763b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 764b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 765b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 766b4ecc126SJeremy Fitzhardinge 7674c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7684c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 769b4ecc126SJeremy Fitzhardinge 7704c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 771b4ecc126SJeremy Fitzhardinge 77245e898b7SWaiman Longconfig QUEUED_LOCK_STAT 77345e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 774cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 77545e898b7SWaiman Long ---help--- 77645e898b7SWaiman Long Enable the collection of statistical data on the slowpath 77745e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 77845e898b7SWaiman Long them on debugfs. 77945e898b7SWaiman Long 7806276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7816276a074SBorislav Petkov 7826276a074SBorislav Petkovconfig KVM_GUEST 7836276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7846276a074SBorislav Petkov depends on PARAVIRT 7856276a074SBorislav Petkov select PARAVIRT_CLOCK 7866276a074SBorislav Petkov default y 7876276a074SBorislav Petkov ---help--- 7886276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7896276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7906276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7916276a074SBorislav Petkov underlying device model, the host provides the guest with 7926276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7936276a074SBorislav Petkov 7941e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7951e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7961e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7971e20eb85SSrivatsa Vaddagiri default n 7981e20eb85SSrivatsa Vaddagiri ---help--- 7991e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 8001e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 8011e20eb85SSrivatsa Vaddagiri may incur significant overhead. 8021e20eb85SSrivatsa Vaddagiri 8036276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 8046276a074SBorislav Petkov bool "Paravirtual steal time accounting" 8056276a074SBorislav Petkov depends on PARAVIRT 8066276a074SBorislav Petkov default n 8076276a074SBorislav Petkov ---help--- 8086276a074SBorislav Petkov Select this option to enable fine granularity task steal time 8096276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 8106276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8116276a074SBorislav Petkov that, there can be a small performance impact. 8126276a074SBorislav Petkov 8136276a074SBorislav Petkov If in doubt, say N here. 8146276a074SBorislav Petkov 8157af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8167af192c9SGerd Hoffmann bool 8177af192c9SGerd Hoffmann 8184a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8194a362601SJan Kiszka bool "Jailhouse non-root cell support" 820abde587bSArnd Bergmann depends on X86_64 && PCI 82187e65d05SJan Kiszka select X86_PM_TIMER 8224a362601SJan Kiszka ---help--- 8234a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8244a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8254a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8264a362601SJan Kiszka 8276276a074SBorislav Petkovendif #HYPERVISOR_GUEST 82897349135SJeremy Fitzhardinge 82908677214SYinghai Luconfig NO_BOOTMEM 830774ea0bcSYinghai Lu def_bool y 83108677214SYinghai Lu 832506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 833506f1d07SSam Ravnborg 834506f1d07SSam Ravnborgconfig HPET_TIMER 8353c2362e6SHarvey Harrison def_bool X86_64 836506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8378f9ca475SIngo Molnar ---help--- 838506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 839506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 840506f1d07SSam Ravnborg present. 841506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 842506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 843506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8444e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8454e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 846506f1d07SSam Ravnborg 847506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 848506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 849506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 850506f1d07SSam Ravnborg 851506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 852506f1d07SSam Ravnborg 853506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8543c2362e6SHarvey Harrison def_bool y 8559d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 856506f1d07SSam Ravnborg 857bb24c471SJacob Panconfig APB_TIMER 858933b9463SAlan Cox def_bool y if X86_INTEL_MID 859933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 86006c3df49SJamie Iles select DW_APB_TIMER 861a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 862bb24c471SJacob Pan help 863bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 864bb24c471SJacob Pan The APBT provides a stable time base on SMP 865bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 866bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 867bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 868bb24c471SJacob Pan 8696a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 870506f1d07SSam Ravnborg# The code disables itself when not needed. 8717ae9392cSThomas Petazzoniconfig DMI 8727ae9392cSThomas Petazzoni default y 873cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8746a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8758f9ca475SIngo Molnar ---help--- 8767ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8777ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8787ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8797ae9392cSThomas Petazzoni BIOS code. 8807ae9392cSThomas Petazzoni 881506f1d07SSam Ravnborgconfig GART_IOMMU 88238901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 883506f1d07SSam Ravnborg select SWIOTLB 88423ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8858f9ca475SIngo Molnar ---help--- 886ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 887ced3c42cSIngo Molnar GART based hardware IOMMUs. 888ced3c42cSIngo Molnar 889ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 890ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 891ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 892ced3c42cSIngo Molnar 893ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 894ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 895ced3c42cSIngo Molnar 896ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 897ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 898ced3c42cSIngo Molnar 32-bit limited device. 899ced3c42cSIngo Molnar 900ced3c42cSIngo Molnar If unsure, say Y. 901506f1d07SSam Ravnborg 902506f1d07SSam Ravnborgconfig CALGARY_IOMMU 903506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 904506f1d07SSam Ravnborg select SWIOTLB 9056ea30386SKees Cook depends on X86_64 && PCI 9068f9ca475SIngo Molnar ---help--- 907506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 908506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 909506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 910506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 911506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 912506f1d07SSam Ravnborg prevents them from going anywhere except their intended 913506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 914506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 915506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 916506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 917506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 918506f1d07SSam Ravnborg If unsure, say Y. 919506f1d07SSam Ravnborg 920506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9213c2362e6SHarvey Harrison def_bool y 9223c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 923506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9248f9ca475SIngo Molnar ---help--- 925506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 926506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 927506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 928506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 929506f1d07SSam Ravnborg If unsure, say Y. 930506f1d07SSam Ravnborg 931506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 932506f1d07SSam Ravnborgconfig SWIOTLB 933a1afd01cSJoerg Roedel def_bool y if X86_64 9348f9ca475SIngo Molnar ---help--- 935506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9364454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9374454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9384454d327SJoe Millenbach with more than 3 GB of memory. 9394454d327SJoe Millenbach If unsure, say Y. 940506f1d07SSam Ravnborg 941a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9423120e25eSJan Beulich def_bool y 9433120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 944d25e26b6SLinus Torvalds 9451184dc2fSMike Travisconfig MAXSMP 946ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9476ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 94836f5101aSMike Travis select CPUMASK_OFFSTACK 9498f9ca475SIngo Molnar ---help--- 950ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9511184dc2fSMike Travis If unsure, say N. 952506f1d07SSam Ravnborg 953506f1d07SSam Ravnborgconfig NR_CPUS 95436f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 9552a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 9567bbcbd3dSThomas Gleixner range 2 64 if SMP && X86_32 && X86_BIGSMP 9577bbcbd3dSThomas Gleixner range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK && X86_64 958b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 95978637a97SMike Travis default "1" if !SMP 960b53b5edaSJosh Boyer default "8192" if MAXSMP 961b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 962c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 963c5c19941SKirill A. Shutemov default "64" if SMP 9648f9ca475SIngo Molnar ---help--- 965506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 966bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 967cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 968506f1d07SSam Ravnborg minimum value which makes sense is 2. 969506f1d07SSam Ravnborg 970506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 971506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 972506f1d07SSam Ravnborg 973506f1d07SSam Ravnborgconfig SCHED_SMT 974506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 975c8e56d20SBorislav Petkov depends on SMP 9768f9ca475SIngo Molnar ---help--- 977506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 978506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 979506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 980506f1d07SSam Ravnborg N here. 981506f1d07SSam Ravnborg 982506f1d07SSam Ravnborgconfig SCHED_MC 9833c2362e6SHarvey Harrison def_bool y 9843c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 985c8e56d20SBorislav Petkov depends on SMP 9868f9ca475SIngo Molnar ---help--- 987506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 988506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 989506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 990506f1d07SSam Ravnborg 991de966cf4STim Chenconfig SCHED_MC_PRIO 992de966cf4STim Chen bool "CPU core priorities scheduler support" 9930a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 9940a21fc12SIngo Molnar select X86_INTEL_PSTATE 9950a21fc12SIngo Molnar select CPU_FREQ 996de966cf4STim Chen default y 9975e76b2abSTim Chen ---help--- 998de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 999de966cf4STim Chen core ordering determined at manufacturing time, which allows 1000de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1001de966cf4STim Chen single threaded workloads) than others. 1002de966cf4STim Chen 1003de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1004de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1005de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1006de966cf4STim Chen overall system performance can be achieved. 1007de966cf4STim Chen 1008de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1009de966cf4STim Chen 1010de966cf4STim Chen If unsure say Y here. 10115e76b2abSTim Chen 1012506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 1013506f1d07SSam Ravnborg 101430b8b006SThomas Gleixnerconfig UP_LATE_INIT 101530b8b006SThomas Gleixner def_bool y 1016ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 101730b8b006SThomas Gleixner 1018506f1d07SSam Ravnborgconfig X86_UP_APIC 101950849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 102050849eefSJan Beulich default PCI_MSI 102138a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10228f9ca475SIngo Molnar ---help--- 1023506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1024506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1025506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1026506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1027506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1028506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1029506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1030506f1d07SSam Ravnborg lockups. 1031506f1d07SSam Ravnborg 1032506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1033506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1034506f1d07SSam Ravnborg depends on X86_UP_APIC 10358f9ca475SIngo Molnar ---help--- 1036506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1037506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1038506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1039506f1d07SSam Ravnborg 1040506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1041506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1042506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1043506f1d07SSam Ravnborg 1044506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10453c2362e6SHarvey Harrison def_bool y 10460dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1047b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 104852f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1049506f1d07SSam Ravnborg 1050506f1d07SSam Ravnborgconfig X86_IO_APIC 1051b1da1e71SJan Beulich def_bool y 1052b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1053506f1d07SSam Ravnborg 105441b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 105541b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 105641b9eb26SStefan Assmann depends on X86_IO_APIC 10578f9ca475SIngo Molnar ---help--- 105841b9eb26SStefan Assmann This option enables a workaround that fixes a source of 105941b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 106041b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 106141b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 106241b9eb26SStefan Assmann 106341b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 106441b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 106541b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 106641b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 106741b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 106841b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 106941b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 107041b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 107141b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 107241b9eb26SStefan Assmann down (vital) interrupt lines. 107341b9eb26SStefan Assmann 107441b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 107541b9eb26SStefan Assmann increased on these systems. 107641b9eb26SStefan Assmann 1077506f1d07SSam Ravnborgconfig X86_MCE 1078bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1079648ed940SChen, Gong select GENERIC_ALLOCATOR 1080e57dbaf7SBorislav Petkov default y 1081506f1d07SSam Ravnborg ---help--- 1082bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1083bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1084506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1085bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10864efc0670SAndi Kleen 10875de97c9fSTony Luckconfig X86_MCELOG_LEGACY 10885de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 10895de97c9fSTony Luck depends on X86_MCE 10905de97c9fSTony Luck ---help--- 10915de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 10925de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 10935de97c9fSTony Luck rasdaemon solution. 10945de97c9fSTony Luck 1095506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10963c2362e6SHarvey Harrison def_bool y 10973c2362e6SHarvey Harrison prompt "Intel MCE features" 1098c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10998f9ca475SIngo Molnar ---help--- 1100506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1101506f1d07SSam Ravnborg the thermal monitor. 1102506f1d07SSam Ravnborg 1103506f1d07SSam Ravnborgconfig X86_MCE_AMD 11043c2362e6SHarvey Harrison def_bool y 11053c2362e6SHarvey Harrison prompt "AMD MCE features" 1106f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11078f9ca475SIngo Molnar ---help--- 1108506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1109506f1d07SSam Ravnborg the DRAM Error Threshold. 1110506f1d07SSam Ravnborg 11114efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11126fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1113c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11144efc0670SAndi Kleen ---help--- 11154efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11165065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11174efc0670SAndi Kleen line. 11184efc0670SAndi Kleen 1119b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1120b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11216fc108a0SJan Beulich def_bool y 1122b2762686SAndi Kleen 1123ea149b36SAndi Kleenconfig X86_MCE_INJECT 1124bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1125ea149b36SAndi Kleen tristate "Machine check injector support" 1126ea149b36SAndi Kleen ---help--- 1127ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1128ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1129ea149b36SAndi Kleen QA it is safe to say n. 1130ea149b36SAndi Kleen 11314efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11324efc0670SAndi Kleen def_bool y 11335bb38adcSAndi Kleen depends on X86_MCE_INTEL 11344efc0670SAndi Kleen 113507dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1136e633c65aSKan Liang 11375aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11381e642812SIngo Molnar bool "Legacy VM86 support" 11395aef51c3SAndy Lutomirski default n 1140506f1d07SSam Ravnborg depends on X86_32 11418f9ca475SIngo Molnar ---help--- 11425aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11435aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11445aef51c3SAndy Lutomirski 11455aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11465aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11475aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11485aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11495aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11501e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11511e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11521e642812SIngo Molnar mode might be faster than emulation and you might want to 11531e642812SIngo Molnar enable this option. 11545aef51c3SAndy Lutomirski 11551e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11561e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11571e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11581e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11595aef51c3SAndy Lutomirski 11601e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11611e642812SIngo Molnar and slows down exception handling a tiny bit. 11625aef51c3SAndy Lutomirski 11631e642812SIngo Molnar If unsure, say N here. 11645aef51c3SAndy Lutomirski 11655aef51c3SAndy Lutomirskiconfig VM86 11665aef51c3SAndy Lutomirski bool 11675aef51c3SAndy Lutomirski default X86_LEGACY_VM86 116834273f41SH. Peter Anvin 116934273f41SH. Peter Anvinconfig X86_16BIT 117034273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 117134273f41SH. Peter Anvin default y 1172a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 117334273f41SH. Peter Anvin ---help--- 117434273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 117534273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 117634273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 117734273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 117834273f41SH. Peter Anvin 117934273f41SH. Peter Anvinconfig X86_ESPFIX32 118034273f41SH. Peter Anvin def_bool y 118134273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1182506f1d07SSam Ravnborg 1183197725deSH. Peter Anvinconfig X86_ESPFIX64 1184197725deSH. Peter Anvin def_bool y 118534273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1186506f1d07SSam Ravnborg 11871ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 11881ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 11891ad83c85SAndy Lutomirski default y 11901ad83c85SAndy Lutomirski depends on X86_64 11911ad83c85SAndy Lutomirski ---help--- 11921ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 11931ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 11941ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11951ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11961ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11971ad83c85SAndy Lutomirski 0xffffffffff600?00. 11981ad83c85SAndy Lutomirski 11991ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12001ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12011ad83c85SAndy Lutomirski 12021ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12031ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12041ad83c85SAndy Lutomirski 1205506f1d07SSam Ravnborgconfig TOSHIBA 1206506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1207506f1d07SSam Ravnborg depends on X86_32 1208506f1d07SSam Ravnborg ---help--- 1209506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1210506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1211506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1212506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1213506f1d07SSam Ravnborg 1214506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1215506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1216506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1217506f1d07SSam Ravnborg 1218506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1219506f1d07SSam Ravnborg Say N otherwise. 1220506f1d07SSam Ravnborg 1221506f1d07SSam Ravnborgconfig I8K 1222039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1223949a9d70SJean Delvare select HWMON 1224039ae585SPali Rohár select SENSORS_DELL_SMM 1225506f1d07SSam Ravnborg ---help--- 1226039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1227039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1228039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1229039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1230039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1231039ae585SPali Rohár needed userspace package i8kutils. 1232506f1d07SSam Ravnborg 1233039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1234039ae585SPali Rohár use userspace package i8kutils. 1235506f1d07SSam Ravnborg Say N otherwise. 1236506f1d07SSam Ravnborg 1237506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12389ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12399ba16087SJan Beulich depends on X86_32 1240506f1d07SSam Ravnborg ---help--- 1241506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1242506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1243506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1244506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1245506f1d07SSam Ravnborg system. 1246506f1d07SSam Ravnborg 1247506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12485e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1249506f1d07SSam Ravnborg 1250506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1251506f1d07SSam Ravnborg enable this option even if you don't need it. 1252506f1d07SSam Ravnborg Say N otherwise. 1253506f1d07SSam Ravnborg 1254506f1d07SSam Ravnborgconfig MICROCODE 12559a2bc335SBorislav Petkov bool "CPU microcode loading support" 12569a2bc335SBorislav Petkov default y 125780030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1258506f1d07SSam Ravnborg select FW_LOADER 1259506f1d07SSam Ravnborg ---help--- 1260506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12615f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12625f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12635f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12645f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12655f9c01aaSBorislav Petkov the Linux kernel. 1266506f1d07SSam Ravnborg 12675f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12685f9c01aaSBorislav Petkov in Documentation/x86/early-microcode.txt. For that you need to enable 12695f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12705f9c01aaSBorislav Petkov initrd for microcode blobs. 1271506f1d07SSam Ravnborg 1272c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1273c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1274c508c46eSBenjamin Gilbert config option. 1275506f1d07SSam Ravnborg 12768d86f390SPeter Orubaconfig MICROCODE_INTEL 1277e43f6e67SBorislav Petkov bool "Intel microcode loading support" 12788d86f390SPeter Oruba depends on MICROCODE 12798d86f390SPeter Oruba default MICROCODE 12808d86f390SPeter Oruba select FW_LOADER 12818f9ca475SIngo Molnar ---help--- 12828d86f390SPeter Oruba This options enables microcode patch loading support for Intel 12838d86f390SPeter Oruba processors. 12848d86f390SPeter Oruba 1285b8989db9SAlan For the current Intel microcode data package go to 1286b8989db9SAlan <https://downloadcenter.intel.com> and search for 1287b8989db9SAlan 'Linux Processor Microcode Data File'. 12888d86f390SPeter Oruba 128980cc9f10SPeter Orubaconfig MICROCODE_AMD 1290e43f6e67SBorislav Petkov bool "AMD microcode loading support" 129180cc9f10SPeter Oruba depends on MICROCODE 129280cc9f10SPeter Oruba select FW_LOADER 12938f9ca475SIngo Molnar ---help--- 129480cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 129580cc9f10SPeter Oruba processors will be enabled. 129680cc9f10SPeter Oruba 1297506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12983c2362e6SHarvey Harrison def_bool y 1299506f1d07SSam Ravnborg depends on MICROCODE 1300506f1d07SSam Ravnborg 1301506f1d07SSam Ravnborgconfig X86_MSR 1302506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13038f9ca475SIngo Molnar ---help--- 1304506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1305506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1306506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1307506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1308506f1d07SSam Ravnborg systems. 1309506f1d07SSam Ravnborg 1310506f1d07SSam Ravnborgconfig X86_CPUID 1311506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13128f9ca475SIngo Molnar ---help--- 1313506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1314506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1315506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1316506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1317506f1d07SSam Ravnborg 1318506f1d07SSam Ravnborgchoice 1319506f1d07SSam Ravnborg prompt "High Memory Support" 13206fc108a0SJan Beulich default HIGHMEM4G 1321506f1d07SSam Ravnborg depends on X86_32 1322506f1d07SSam Ravnborg 1323506f1d07SSam Ravnborgconfig NOHIGHMEM 1324506f1d07SSam Ravnborg bool "off" 1325506f1d07SSam Ravnborg ---help--- 1326506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1327506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1328506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1329506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1330506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1331506f1d07SSam Ravnborg "high memory". 1332506f1d07SSam Ravnborg 1333506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1334506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1335506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1336506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1337506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1338506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1339506f1d07SSam Ravnborg possible. 1340506f1d07SSam Ravnborg 1341506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1342506f1d07SSam Ravnborg answer "4GB" here. 1343506f1d07SSam Ravnborg 1344506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1345506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1346506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1347506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1348506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1349506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1350506f1d07SSam Ravnborg 1351506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1352506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1353506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1354506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1355506f1d07SSam Ravnborg kernel at boot time.) 1356506f1d07SSam Ravnborg 1357506f1d07SSam Ravnborg If unsure, say "off". 1358506f1d07SSam Ravnborg 1359506f1d07SSam Ravnborgconfig HIGHMEM4G 1360506f1d07SSam Ravnborg bool "4GB" 13618f9ca475SIngo Molnar ---help--- 1362506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1363506f1d07SSam Ravnborg gigabytes of physical RAM. 1364506f1d07SSam Ravnborg 1365506f1d07SSam Ravnborgconfig HIGHMEM64G 1366506f1d07SSam Ravnborg bool "64GB" 1367eb068e78SH. Peter Anvin depends on !M486 1368506f1d07SSam Ravnborg select X86_PAE 13698f9ca475SIngo Molnar ---help--- 1370506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1371506f1d07SSam Ravnborg gigabytes of physical RAM. 1372506f1d07SSam Ravnborg 1373506f1d07SSam Ravnborgendchoice 1374506f1d07SSam Ravnborg 1375506f1d07SSam Ravnborgchoice 13766a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1377506f1d07SSam Ravnborg default VMSPLIT_3G 1378506f1d07SSam Ravnborg depends on X86_32 13798f9ca475SIngo Molnar ---help--- 1380506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1381506f1d07SSam Ravnborg 1382506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1383506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1384506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1385506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1386506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1387506f1d07SSam Ravnborg available to user programs, making the address space there 1388506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1389506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1390506f1d07SSam Ravnborg kernel modules. 1391506f1d07SSam Ravnborg 1392506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1393506f1d07SSam Ravnborg option alone! 1394506f1d07SSam Ravnborg 1395506f1d07SSam Ravnborg config VMSPLIT_3G 1396506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1397506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1398506f1d07SSam Ravnborg depends on !X86_PAE 1399506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1400506f1d07SSam Ravnborg config VMSPLIT_2G 1401506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1402506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1403506f1d07SSam Ravnborg depends on !X86_PAE 1404506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1405506f1d07SSam Ravnborg config VMSPLIT_1G 1406506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1407506f1d07SSam Ravnborgendchoice 1408506f1d07SSam Ravnborg 1409506f1d07SSam Ravnborgconfig PAGE_OFFSET 1410506f1d07SSam Ravnborg hex 1411506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1412506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1413506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1414506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1415506f1d07SSam Ravnborg default 0xC0000000 1416506f1d07SSam Ravnborg depends on X86_32 1417506f1d07SSam Ravnborg 1418506f1d07SSam Ravnborgconfig HIGHMEM 14193c2362e6SHarvey Harrison def_bool y 1420506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1421506f1d07SSam Ravnborg 1422506f1d07SSam Ravnborgconfig X86_PAE 14239ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1424506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 14259d99c712SChristian Melki select SWIOTLB 14268f9ca475SIngo Molnar ---help--- 1427506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1428506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1429506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1430506f1d07SSam Ravnborg consumes more pagetable space per process. 1431506f1d07SSam Ravnborg 143277ef56e4SKirill A. Shutemovconfig X86_5LEVEL 143377ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 143477ef56e4SKirill A. Shutemov depends on X86_64 143577ef56e4SKirill A. Shutemov ---help--- 143677ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 143777ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 143877ef56e4SKirill A. Shutemov physical address space. 143977ef56e4SKirill A. Shutemov 144077ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 144177ef56e4SKirill A. Shutemov 144277ef56e4SKirill A. Shutemov Note: a kernel with this option enabled can only be booted 144377ef56e4SKirill A. Shutemov on machines that support the feature. 144477ef56e4SKirill A. Shutemov 144577ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 144677ef56e4SKirill A. Shutemov information. 144777ef56e4SKirill A. Shutemov 144877ef56e4SKirill A. Shutemov Say N if unsure. 144977ef56e4SKirill A. Shutemov 1450600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14513120e25eSJan Beulich def_bool y 14523120e25eSJan Beulich depends on X86_64 || X86_PAE 1453600715dcSJeremy Fitzhardinge 145466f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14553120e25eSJan Beulich def_bool y 14563120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 145766f2b061SFUJITA Tomonori 145810971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1459e5008abeSLuis R. Rodriguez def_bool y 14604675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 14618f9ca475SIngo Molnar ---help--- 146210971ab2SIngo Molnar Certain kernel features effectively disable kernel 146310971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 146410971ab2SIngo Molnar supports them), so don't confuse the user by printing 146510971ab2SIngo Molnar that we have them enabled. 14669e899816SNick Piggin 14677744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 14687744ccdbSTom Lendacky def_bool y 14697744ccdbSTom Lendacky 14707744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 14717744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 14727744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 14737744ccdbSTom Lendacky ---help--- 14747744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 14757744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 14767744ccdbSTom Lendacky Encryption (SME). 14777744ccdbSTom Lendacky 14787744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 14797744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 14807744ccdbSTom Lendacky default y 14817744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 14827744ccdbSTom Lendacky ---help--- 14837744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 14847744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 14857744ccdbSTom Lendacky 14867744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 14877744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 14887744ccdbSTom Lendacky 14897744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 14907744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 14917744ccdbSTom Lendacky 1492f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1493f88a68faSTom Lendacky def_bool y 1494f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1495f88a68faSTom Lendacky 1496506f1d07SSam Ravnborg# Common NUMA Features 1497506f1d07SSam Ravnborgconfig NUMA 1498fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1499506f1d07SSam Ravnborg depends on SMP 1500b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1501b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15028f9ca475SIngo Molnar ---help--- 1503506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1504fd51b2d7SKOSAKI Motohiro 1505506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1506506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1507506f1d07SSam Ravnborg NUMA awareness to the kernel. 1508506f1d07SSam Ravnborg 1509c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1510fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1511fd51b2d7SKOSAKI Motohiro 1512b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15137cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1514fd51b2d7SKOSAKI Motohiro 1515fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1516506f1d07SSam Ravnborg 1517eec1d4faSHans Rosenfeldconfig AMD_NUMA 15183c2362e6SHarvey Harrison def_bool y 15193c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15205da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15218f9ca475SIngo Molnar ---help--- 1522eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1523eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1524eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1525eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1526eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1527506f1d07SSam Ravnborg 1528506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15293c2362e6SHarvey Harrison def_bool y 15303c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1531506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1532506f1d07SSam Ravnborg select ACPI_NUMA 15338f9ca475SIngo Molnar ---help--- 1534506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1535506f1d07SSam Ravnborg 15366ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15376ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15386ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15396ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15406ec6e0d9SSuresh Siddha# for details. 15416ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15426ec6e0d9SSuresh Siddha def_bool y 15436ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15446ec6e0d9SSuresh Siddha 1545506f1d07SSam Ravnborgconfig NUMA_EMU 1546506f1d07SSam Ravnborg bool "NUMA emulation" 15471b7e03efSTejun Heo depends on NUMA 15488f9ca475SIngo Molnar ---help--- 1549506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1550506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1551506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1552506f1d07SSam Ravnborg 1553506f1d07SSam Ravnborgconfig NODES_SHIFT 1554d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 155551591e31SDavid Rientjes range 1 10 155651591e31SDavid Rientjes default "10" if MAXSMP 1557506f1d07SSam Ravnborg default "6" if X86_64 1558506f1d07SSam Ravnborg default "3" 1559506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15608f9ca475SIngo Molnar ---help--- 15611184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1562692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1563506f1d07SSam Ravnborg 1564506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15653c2362e6SHarvey Harrison def_bool y 1566506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1567506f1d07SSam Ravnborg 1568506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 15693c2362e6SHarvey Harrison def_bool y 1570506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1571506f1d07SSam Ravnborg 1572506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1573506f1d07SSam Ravnborg def_bool y 15743b16651fSTejun Heo depends on X86_32 && !NUMA 1575506f1d07SSam Ravnborg 1576506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1577506f1d07SSam Ravnborg def_bool y 1578b263295dSChristoph Lameter depends on NUMA && X86_32 1579506f1d07SSam Ravnborg 1580506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1581506f1d07SSam Ravnborg def_bool y 1582b263295dSChristoph Lameter depends on NUMA && X86_32 1583b263295dSChristoph Lameter 1584506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1585506f1d07SSam Ravnborg def_bool y 15866ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1587506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1588506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1589506f1d07SSam Ravnborg 15903b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 15913b16651fSTejun Heo def_bool y 15923b16651fSTejun Heo depends on X86_64 15933b16651fSTejun Heo 1594506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1595506f1d07SSam Ravnborg def_bool y 1596b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1597506f1d07SSam Ravnborg 1598506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1599a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16003120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1601a0842b70SToshi Kani help 1602a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1603a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1604a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1605506f1d07SSam Ravnborg 16063b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16073b16651fSTejun Heo def_bool y 16083b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16093b16651fSTejun Heo 1610a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1611a29815a3SAvi Kivity hex 1612a29815a3SAvi Kivity default 0 if X86_32 1613a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1614a29815a3SAvi Kivity 1615506f1d07SSam Ravnborgsource "mm/Kconfig" 1616506f1d07SSam Ravnborg 16177a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16187a67832cSDan Williams bool 16197a67832cSDan Williams 1620ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16217a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16229f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16239f53f9faSDan Williams depends on BLK_DEV 16247a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16259f53f9faSDan Williams select LIBNVDIMM 1626ec776ef6SChristoph Hellwig help 1627ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1628ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1629ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1630ec776ef6SChristoph Hellwig they can be used for persistent storage. 1631ec776ef6SChristoph Hellwig 1632ec776ef6SChristoph Hellwig Say Y if unsure. 1633ec776ef6SChristoph Hellwig 1634506f1d07SSam Ravnborgconfig HIGHPTE 1635506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16366fc108a0SJan Beulich depends on HIGHMEM 16378f9ca475SIngo Molnar ---help--- 1638506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1639506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1640506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1641506f1d07SSam Ravnborg entries in high memory. 1642506f1d07SSam Ravnborg 16439f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16449f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16458f9ca475SIngo Molnar ---help--- 16469f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16479f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16489f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16499f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16509f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16519f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16529f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16538c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16549f077871SJeremy Fitzhardinge 16559f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16569f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16579f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16589f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16599f077871SJeremy Fitzhardinge 16609f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16619f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16629f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16639f077871SJeremy Fitzhardinge memory. 16649f077871SJeremy Fitzhardinge 1665c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1666c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1667c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1668c885df50SJeremy Fitzhardinge default y 16698f9ca475SIngo Molnar ---help--- 1670c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1671c885df50SJeremy Fitzhardinge on or off. 1672c885df50SJeremy Fitzhardinge 16739ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1674d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1675d0cd7425SH. Peter Anvin default 64 1676d0cd7425SH. Peter Anvin range 4 640 16778f9ca475SIngo Molnar ---help--- 1678d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1679fc381519SIngo Molnar 1680d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1681d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1682fc381519SIngo Molnar 1683d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1684d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1685d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1686d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1687fc381519SIngo Molnar 1688d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1689d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1690d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1691d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1692d0cd7425SH. Peter Anvin entire low memory range. 1693d0cd7425SH. Peter Anvin 1694d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1695d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1696d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1697d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1698d0cd7425SH. Peter Anvin typical corruption patterns. 1699d0cd7425SH. Peter Anvin 1700d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1701fc381519SIngo Molnar 1702506f1d07SSam Ravnborgconfig MATH_EMULATION 1703506f1d07SSam Ravnborg bool 1704a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1705506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1706506f1d07SSam Ravnborg ---help--- 1707506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1708506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1709506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1710506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1711506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1712506f1d07SSam Ravnborg coprocessor or this emulation. 1713506f1d07SSam Ravnborg 1714506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1715506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1716506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1717506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1718506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1719506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1720506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1721506f1d07SSam Ravnborg intend to use this kernel on different machines. 1722506f1d07SSam Ravnborg 1723506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1724506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1725506f1d07SSam Ravnborg 1726506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1727506f1d07SSam Ravnborg kernel, it won't hurt. 1728506f1d07SSam Ravnborg 1729506f1d07SSam Ravnborgconfig MTRR 17306fc108a0SJan Beulich def_bool y 17316a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1732506f1d07SSam Ravnborg ---help--- 1733506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1734506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1735506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1736506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1737506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1738506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1739506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1740506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1741506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1742506f1d07SSam Ravnborg 1743506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1744506f1d07SSam Ravnborg control registers on other processors can be easily supported 1745506f1d07SSam Ravnborg as well: 1746506f1d07SSam Ravnborg 1747506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1748506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1749506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1750506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1751506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1752506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1753506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1754506f1d07SSam Ravnborg 1755506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1756506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1757506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1758506f1d07SSam Ravnborg 1759506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1760506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1761506f1d07SSam Ravnborg 17627225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1763506f1d07SSam Ravnborg 176495ffa243SYinghai Luconfig MTRR_SANITIZER 17652ffb3501SYinghai Lu def_bool y 176695ffa243SYinghai Lu prompt "MTRR cleanup support" 176795ffa243SYinghai Lu depends on MTRR 17688f9ca475SIngo Molnar ---help--- 1769aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1770aba3728cSThomas Gleixner add writeback entries. 177195ffa243SYinghai Lu 1772aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1773692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1774aba3728cSThomas Gleixner mtrr_chunk_size. 177595ffa243SYinghai Lu 17762ffb3501SYinghai Lu If unsure, say Y. 177795ffa243SYinghai Lu 177895ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1779f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1780f5098d62SYinghai Lu range 0 1 1781f5098d62SYinghai Lu default "0" 178295ffa243SYinghai Lu depends on MTRR_SANITIZER 17838f9ca475SIngo Molnar ---help--- 1784f5098d62SYinghai Lu Enable mtrr cleanup default value 178595ffa243SYinghai Lu 178612031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 178712031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 178812031a62SYinghai Lu range 0 7 178912031a62SYinghai Lu default "1" 179012031a62SYinghai Lu depends on MTRR_SANITIZER 17918f9ca475SIngo Molnar ---help--- 179212031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1793aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 179412031a62SYinghai Lu 17952e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 17966fc108a0SJan Beulich def_bool y 17976a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 17982a8a2719SIngo Molnar depends on MTRR 17998f9ca475SIngo Molnar ---help--- 18002e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1801042b78e4SVenki Pallipadi 18022e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18032e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18042e5d9c85Svenkatesh.pallipadi@intel.com 18052e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1806042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18072e5d9c85Svenkatesh.pallipadi@intel.com 18082e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18092e5d9c85Svenkatesh.pallipadi@intel.com 181046cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 181146cf98cdSVenkatesh Pallipadi def_bool y 181246cf98cdSVenkatesh Pallipadi depends on X86_PAT 181346cf98cdSVenkatesh Pallipadi 1814628c6246SH. Peter Anvinconfig ARCH_RANDOM 1815628c6246SH. Peter Anvin def_bool y 1816628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1817628c6246SH. Peter Anvin ---help--- 1818628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1819628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1820628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1821628c6246SH. Peter Anvin secure hardware random number generator. 1822628c6246SH. Peter Anvin 182351ae4a2dSH. Peter Anvinconfig X86_SMAP 182451ae4a2dSH. Peter Anvin def_bool y 182551ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 182651ae4a2dSH. Peter Anvin ---help--- 182751ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 182851ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 182951ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 183051ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 183151ae4a2dSH. Peter Anvin 183251ae4a2dSH. Peter Anvin If unsure, say Y. 183351ae4a2dSH. Peter Anvin 1834aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1835796ebc81SRicardo Neri def_bool y 1836aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1837aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1838aa35f896SRicardo Neri ---help--- 1839aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1840aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1841796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1842796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1843796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1844796ebc81SRicardo Neri 1845796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1846796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1847796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1848796ebc81SRicardo Neri results are dummy. 1849aa35f896SRicardo Neri 185072e9b5feSDave Hansenconfig X86_INTEL_MPX 185172e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 185272e9b5feSDave Hansen def_bool n 1853df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1854df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1855df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 185672e9b5feSDave Hansen ---help--- 185772e9b5feSDave Hansen MPX provides hardware features that can be used in 185872e9b5feSDave Hansen conjunction with compiler-instrumented code to check 185972e9b5feSDave Hansen memory references. It is designed to detect buffer 186072e9b5feSDave Hansen overflow or underflow bugs. 186172e9b5feSDave Hansen 186272e9b5feSDave Hansen This option enables running applications which are 186372e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 186472e9b5feSDave Hansen itself inside the kernel or to protect the kernel 186572e9b5feSDave Hansen against bad memory references. 186672e9b5feSDave Hansen 186772e9b5feSDave Hansen Enabling this option will make the kernel larger: 186872e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 186972e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 187072e9b5feSDave Hansen will increase the kernel memory overhead of each 187172e9b5feSDave Hansen process and adds some branches to paths used during 187272e9b5feSDave Hansen exec() and munmap(). 187372e9b5feSDave Hansen 187472e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 187572e9b5feSDave Hansen 187672e9b5feSDave Hansen If unsure, say N. 187772e9b5feSDave Hansen 187835e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1879284244a9SDave Hansen prompt "Intel Memory Protection Keys" 188035e97790SDave Hansen def_bool y 1881284244a9SDave Hansen # Note: only available in 64-bit mode 188235e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 188352c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 188452c8e601SIngo Molnar select ARCH_HAS_PKEYS 1885284244a9SDave Hansen ---help--- 1886284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1887284244a9SDave Hansen page-based protections, but without requiring modification of the 1888284244a9SDave Hansen page tables when an application changes protection domains. 1889284244a9SDave Hansen 1890284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1891284244a9SDave Hansen 1892284244a9SDave Hansen If unsure, say y. 189335e97790SDave Hansen 1894506f1d07SSam Ravnborgconfig EFI 18959ba16087SJan Beulich bool "EFI runtime service support" 18965b83683fSHuang, Ying depends on ACPI 1897f6ce5002SSergey Vlasov select UCS2_STRING 1898022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1899506f1d07SSam Ravnborg ---help--- 19008b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1901506f1d07SSam Ravnborg available (such as the EFI variable services). 1902506f1d07SSam Ravnborg 19038b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19048b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19058b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19068b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19078b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19088b2cb7a8SHuang, Ying platforms. 1909506f1d07SSam Ravnborg 1910291f3632SMatt Flemingconfig EFI_STUB 1911291f3632SMatt Fleming bool "EFI stub support" 1912b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19137b2a583aSMatt Fleming select RELOCATABLE 1914291f3632SMatt Fleming ---help--- 1915291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1916291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1917291f3632SMatt Fleming 19184172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19190c759662SMatt Fleming 19207d453eeeSMatt Flemingconfig EFI_MIXED 19217d453eeeSMatt Fleming bool "EFI mixed-mode support" 19227d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19237d453eeeSMatt Fleming ---help--- 19247d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19257d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19267d453eeeSMatt Fleming mode. 19277d453eeeSMatt Fleming 19287d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19297d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19307d453eeeSMatt Fleming the EFI handover protocol must be used. 19317d453eeeSMatt Fleming 19327d453eeeSMatt Fleming If unsure, say N. 19337d453eeeSMatt Fleming 1934506f1d07SSam Ravnborgconfig SECCOMP 19353c2362e6SHarvey Harrison def_bool y 19363c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19378f9ca475SIngo Molnar ---help--- 1938506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1939506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1940506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1941506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1942506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1943506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19449c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1945506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1946506f1d07SSam Ravnborg defined by each seccomp mode. 1947506f1d07SSam Ravnborg 1948506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1949506f1d07SSam Ravnborg 1950506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1951506f1d07SSam Ravnborg 1952506f1d07SSam Ravnborgconfig KEXEC 1953506f1d07SSam Ravnborg bool "kexec system call" 19542965faa5SDave Young select KEXEC_CORE 19558f9ca475SIngo Molnar ---help--- 1956506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1957506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1958506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1959506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1960506f1d07SSam Ravnborg 1961506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1962506f1d07SSam Ravnborg 1963506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1964506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1965bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1966bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1967bf220695SGeert Uytterhoeven made. 1968506f1d07SSam Ravnborg 196974ca317cSVivek Goyalconfig KEXEC_FILE 197074ca317cSVivek Goyal bool "kexec file based system call" 19712965faa5SDave Young select KEXEC_CORE 197274ca317cSVivek Goyal select BUILD_BIN2C 197374ca317cSVivek Goyal depends on X86_64 197474ca317cSVivek Goyal depends on CRYPTO=y 197574ca317cSVivek Goyal depends on CRYPTO_SHA256=y 197674ca317cSVivek Goyal ---help--- 197774ca317cSVivek Goyal This is new version of kexec system call. This system call is 197874ca317cSVivek Goyal file based and takes file descriptors as system call argument 197974ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 198074ca317cSVivek Goyal accepted by previous system call. 198174ca317cSVivek Goyal 19828e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 19838e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 198474ca317cSVivek Goyal depends on KEXEC_FILE 19858e7d8381SVivek Goyal ---help--- 19868e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1987d8eb8940SBorislav Petkov the kexec_file_load() syscall. 19888e7d8381SVivek Goyal 1989d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1990d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1991d8eb8940SBorislav Petkov loaded in order for this to work. 19928e7d8381SVivek Goyal 19938e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 19948e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 19958e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 19968e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 19978e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 19988e7d8381SVivek Goyal ---help--- 19998e7d8381SVivek Goyal Enable bzImage signature verification support. 20008e7d8381SVivek Goyal 2001506f1d07SSam Ravnborgconfig CRASH_DUMP 200204b69447SPavel Machek bool "kernel crash dumps" 2003506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20048f9ca475SIngo Molnar ---help--- 2005506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2006506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2007506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2008506f1d07SSam Ravnborg a specially reserved region and then later executed after 2009506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2010506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2011506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2012506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2013506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2014506f1d07SSam Ravnborg 20153ab83521SHuang Yingconfig KEXEC_JUMP 20166ea30386SKees Cook bool "kexec jump" 2017fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20188f9ca475SIngo Molnar ---help--- 201989081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 202089081d17SHuang Ying code in physical address mode via KEXEC 20213ab83521SHuang Ying 2022506f1d07SSam Ravnborgconfig PHYSICAL_START 20236a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2024ceefccc9SH. Peter Anvin default "0x1000000" 20258f9ca475SIngo Molnar ---help--- 2026506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2027506f1d07SSam Ravnborg 2028506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2029506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2030506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2031506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2032506f1d07SSam Ravnborg address. 2033506f1d07SSam Ravnborg 2034506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2035506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2036506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2037506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2038506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2039506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2040506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2041506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2042506f1d07SSam Ravnborg 2043ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2044ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2045ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2046ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2047ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2048ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2049ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2050ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2051ceefccc9SH. Peter Anvin for more details about crash dumps. 2052506f1d07SSam Ravnborg 2053506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2054506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2055506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2056506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2057506f1d07SSam Ravnborg is present because there are users out there who continue to use 2058506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2059506f1d07SSam Ravnborg line. 2060506f1d07SSam Ravnborg 2061506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2062506f1d07SSam Ravnborg 2063506f1d07SSam Ravnborgconfig RELOCATABLE 206426717808SH. Peter Anvin bool "Build a relocatable kernel" 206526717808SH. Peter Anvin default y 20668f9ca475SIngo Molnar ---help--- 2067506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2068506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2069506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2070506f1d07SSam Ravnborg but are discarded at runtime. 2071506f1d07SSam Ravnborg 2072506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2073506f1d07SSam Ravnborg must live at a different physical address than the primary 2074506f1d07SSam Ravnborg kernel. 2075506f1d07SSam Ravnborg 2076506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2077506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 20788ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2079506f1d07SSam Ravnborg 20808ab3820fSKees Cookconfig RANDOMIZE_BASE 2081e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 20828ab3820fSKees Cook depends on RELOCATABLE 20836807c846SIngo Molnar default y 20848ab3820fSKees Cook ---help--- 2085e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2086e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2087e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2088e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2089e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2090e8581e3dSBaoquan He code internals. 2091e8581e3dSBaoquan He 2092ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2093ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2094ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2095ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2096ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2097ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2098ed9f007eSKees Cook 2099ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2100ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2101ed9f007eSKees Cook 512MB (8 bits of entropy). 21028ab3820fSKees Cook 2103a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2104e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2105e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2106ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2107ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2108ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2109ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2110ed9f007eSKees Cook theoretically possible, but the implementations are further 2111ed9f007eSKees Cook limited due to memory layouts. 2112e8581e3dSBaoquan He 21136807c846SIngo Molnar If unsure, say Y. 2114da2b6fb9SKees Cook 21158ab3820fSKees Cook# Relocation on x86 needs some additional build support 2116845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2117845adf72SH. Peter Anvin def_bool y 21188ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2119845adf72SH. Peter Anvin 2120506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2121a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21228ab3820fSKees Cook default "0x200000" 2123a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2124a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21258f9ca475SIngo Molnar ---help--- 2126506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2127506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2128506f1d07SSam Ravnborg address which meets above alignment restriction. 2129506f1d07SSam Ravnborg 2130506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2131506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2132506f1d07SSam Ravnborg address aligned to above value and run from there. 2133506f1d07SSam Ravnborg 2134506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2135506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2136506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2137506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2138506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2139506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2140506f1d07SSam Ravnborg above alignment restrictions. 2141506f1d07SSam Ravnborg 2142a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2143a0215061SKees Cook this value must be a multiple of 0x200000. 2144a0215061SKees Cook 2145506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2146506f1d07SSam Ravnborg 21470483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21480483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21490483e1faSThomas Garnier depends on X86_64 21500483e1faSThomas Garnier depends on RANDOMIZE_BASE 21510483e1faSThomas Garnier default RANDOMIZE_BASE 21520483e1faSThomas Garnier ---help--- 21530483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21540483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21550483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21560483e1faSThomas Garnier 21570483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21580483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21590483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21600483e1faSThomas Garnier addresses for each memory section. 21610483e1faSThomas Garnier 21626807c846SIngo Molnar If unsure, say Y. 21630483e1faSThomas Garnier 216490397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 216590397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 216690397a41SThomas Garnier depends on RANDOMIZE_MEMORY 216790397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 216890397a41SThomas Garnier default "0x0" 216990397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 217090397a41SThomas Garnier range 0x0 0x40 217190397a41SThomas Garnier ---help--- 217290397a41SThomas Garnier Define the padding in terabytes added to the existing physical 217390397a41SThomas Garnier memory size during kernel memory randomization. It is useful 217490397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 217590397a41SThomas Garnier address randomization. 217690397a41SThomas Garnier 217790397a41SThomas Garnier If unsure, leave at the default value. 217890397a41SThomas Garnier 2179506f1d07SSam Ravnborgconfig HOTPLUG_CPU 21807c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 218140b31360SStephen Rothwell depends on SMP 2182506f1d07SSam Ravnborg ---help--- 21837c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 21847c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 21857c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 21867c13e6a3SDimitri Sivanich automatically on SMP systems. ) 21877c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2188506f1d07SSam Ravnborg 218980aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 219080aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 219180aa1dffSFenghua Yu default n 21922c922cd0SKees Cook depends on HOTPLUG_CPU 219380aa1dffSFenghua Yu ---help--- 219480aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 219580aa1dffSFenghua Yu 219680aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 219780aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 219880aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 219980aa1dffSFenghua Yu 220080aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 220180aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 220280aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 220380aa1dffSFenghua Yu 220480aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 220580aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 220680aa1dffSFenghua Yu 220780aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 220880aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 220980aa1dffSFenghua Yu be other CPU0 dependencies. 221080aa1dffSFenghua Yu 221180aa1dffSFenghua Yu Please make sure the dependencies are under your control before 221280aa1dffSFenghua Yu you enable this feature. 221380aa1dffSFenghua Yu 221480aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 221580aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 221680aa1dffSFenghua Yu parameter cpu0_hotplug. 221780aa1dffSFenghua Yu 2218a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2219a71c8bc5SFenghua Yu def_bool n 2220a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 22212c922cd0SKees Cook depends on HOTPLUG_CPU 2222a71c8bc5SFenghua Yu ---help--- 2223a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2224a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2225a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2226a71c8bc5SFenghua Yu 2227a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2228a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2229a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2230a71c8bc5SFenghua Yu 2231a71c8bc5SFenghua Yu If unsure, say N. 2232a71c8bc5SFenghua Yu 2233506f1d07SSam Ravnborgconfig COMPAT_VDSO 2234b0b49f26SAndy Lutomirski def_bool n 2235b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2236953fee1dSIngo Molnar depends on COMPAT_32 22378f9ca475SIngo Molnar ---help--- 2238b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2239b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2240b0b49f26SAndy Lutomirski indicated in its segment table. 2241e84446deSRandy Dunlap 2242b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2243b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2244b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2245b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2246b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2247506f1d07SSam Ravnborg 2248b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2249b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2250b0b49f26SAndy Lutomirski 2251b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2252b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2253b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2254b0b49f26SAndy Lutomirski 2255b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2256b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2257506f1d07SSam Ravnborg 22583dc33bd3SKees Cookchoice 22593dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22603dc33bd3SKees Cook depends on X86_64 22613dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 22623dc33bd3SKees Cook help 22633dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 22643dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 22653dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 22663dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22673dc33bd3SKees Cook 22683dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 2269*076ca272SAndy Lutomirski line parameter vsyscall=[emulate|none]. 22703dc33bd3SKees Cook 22713dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22723dc33bd3SKees Cook static binaries, you can say None without a performance penalty 22733dc33bd3SKees Cook to improve security. 22743dc33bd3SKees Cook 22753dc33bd3SKees Cook If unsure, select "Emulate". 22763dc33bd3SKees Cook 22773dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 22783dc33bd3SKees Cook bool "Emulate" 22793dc33bd3SKees Cook help 22803dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 22813dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 22823dc33bd3SKees Cook non-executable, but it still contains known contents, 22833dc33bd3SKees Cook which could be used in certain rare security vulnerability 22843dc33bd3SKees Cook exploits. This configuration is recommended when userspace 22853dc33bd3SKees Cook still uses the vsyscall area. 22863dc33bd3SKees Cook 22873dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 22883dc33bd3SKees Cook bool "None" 22893dc33bd3SKees Cook help 22903dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 22913dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 22923dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 22933dc33bd3SKees Cook will be reported to dmesg, so that either old or 22943dc33bd3SKees Cook malicious userspace programs can be identified. 22953dc33bd3SKees Cook 22963dc33bd3SKees Cookendchoice 22973dc33bd3SKees Cook 2298516cbf37STim Birdconfig CMDLINE_BOOL 2299516cbf37STim Bird bool "Built-in kernel command line" 23008f9ca475SIngo Molnar ---help--- 2301516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2302516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2303516cbf37STim Bird necessary or convenient to provide some or all of the 2304516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2305516cbf37STim Bird to not rely on the boot loader to provide them.) 2306516cbf37STim Bird 2307516cbf37STim Bird To compile command line arguments into the kernel, 2308516cbf37STim Bird set this option to 'Y', then fill in the 230969711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2310516cbf37STim Bird 2311516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2312516cbf37STim Bird should leave this option set to 'N'. 2313516cbf37STim Bird 2314516cbf37STim Birdconfig CMDLINE 2315516cbf37STim Bird string "Built-in kernel command string" 2316516cbf37STim Bird depends on CMDLINE_BOOL 2317516cbf37STim Bird default "" 23188f9ca475SIngo Molnar ---help--- 2319516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2320516cbf37STim Bird image and used at boot time. If the boot loader provides a 2321516cbf37STim Bird command line at boot time, it is appended to this string to 2322516cbf37STim Bird form the full kernel command line, when the system boots. 2323516cbf37STim Bird 2324516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2325516cbf37STim Bird change this behavior. 2326516cbf37STim Bird 2327516cbf37STim Bird In most cases, the command line (whether built-in or provided 2328516cbf37STim Bird by the boot loader) should specify the device for the root 2329516cbf37STim Bird file system. 2330516cbf37STim Bird 2331516cbf37STim Birdconfig CMDLINE_OVERRIDE 2332516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2333516cbf37STim Bird depends on CMDLINE_BOOL 23348f9ca475SIngo Molnar ---help--- 2335516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2336516cbf37STim Bird command line, and use ONLY the built-in command line. 2337516cbf37STim Bird 2338516cbf37STim Bird This is used to work around broken boot loaders. This should 2339516cbf37STim Bird be set to 'N' under normal conditions. 2340516cbf37STim Bird 2341a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2342a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2343a5b9e5a2SAndy Lutomirski default y 2344a5b9e5a2SAndy Lutomirski ---help--- 2345a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2346a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2347a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2348a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2349a5b9e5a2SAndy Lutomirski threading libraries. 2350a5b9e5a2SAndy Lutomirski 2351a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2352a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2353a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2354a5b9e5a2SAndy Lutomirski 2355a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2356a5b9e5a2SAndy Lutomirski 2357b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2358b700e7f0SSeth Jennings 2359506f1d07SSam Ravnborgendmenu 2360506f1d07SSam Ravnborg 23613072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 23623072e413SMichal Hocko def_bool y 23633072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 23643072e413SMichal Hocko 2365506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2366506f1d07SSam Ravnborg def_bool y 2367506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2368506f1d07SSam Ravnborg 236935551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 237035551053SGary Hade def_bool y 237135551053SGary Hade depends on MEMORY_HOTPLUG 237235551053SGary Hade 2373e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2374645a7919STejun Heo def_bool y 2375e534c7c5SLee Schermerhorn depends on NUMA 2376e534c7c5SLee Schermerhorn 23779491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 23789491846fSKirill A. Shutemov def_bool y 23799491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 23809491846fSKirill A. Shutemov 2381c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2382c177c81eSNaoya Horiguchi def_bool y 2383c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2384c177c81eSNaoya Horiguchi 23859c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 23869c670ea3SNaoya Horiguchi def_bool y 23879c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 23889c670ea3SNaoya Horiguchi 2389da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2390e279b6c1SSam Ravnborg 2391e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 23923c2362e6SHarvey Harrison def_bool y 2393e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2394e279b6c1SSam Ravnborg 2395e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2396e279b6c1SSam Ravnborg 2397e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2398e279b6c1SSam Ravnborg 2399efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2400efafc8b2SFeng Tang 2401a6b68076SAndi Kleenconfig X86_APM_BOOT 24026fc108a0SJan Beulich def_bool y 2403282e5aabSPaul Bolle depends on APM 2404a6b68076SAndi Kleen 2405e279b6c1SSam Ravnborgmenuconfig APM 2406e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2407efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2408e279b6c1SSam Ravnborg ---help--- 2409e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2410e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2411e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2412e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2413e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2414e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2415e279b6c1SSam Ravnborg 2416e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2417e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2418e279b6c1SSam Ravnborg 2419e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2420e279b6c1SSam Ravnborg machines with more than one CPU. 2421e279b6c1SSam Ravnborg 2422e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 24232dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 24242dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2425e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2426e279b6c1SSam Ravnborg 2427e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2428e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2429e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2430e279b6c1SSam Ravnborg 2431e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2432e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2433e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2434e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2435e279b6c1SSam Ravnborg 2436e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2437e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2438e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2439e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2440e279b6c1SSam Ravnborg APM in your BIOS). 2441e279b6c1SSam Ravnborg 2442e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2443e279b6c1SSam Ravnborg "weird" problems: 2444e279b6c1SSam Ravnborg 2445e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2446e279b6c1SSam Ravnborg enabled. 2447e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2448e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2449e279b6c1SSam Ravnborg the "no387" option to the kernel 2450e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2451e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2452e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2453e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2454e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2455e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2456e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2457e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2458e279b6c1SSam Ravnborg 11) exchange RAM chips 2459e279b6c1SSam Ravnborg 12) exchange the motherboard. 2460e279b6c1SSam Ravnborg 2461e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2462e279b6c1SSam Ravnborg module will be called apm. 2463e279b6c1SSam Ravnborg 2464e279b6c1SSam Ravnborgif APM 2465e279b6c1SSam Ravnborg 2466e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2467e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 24688f9ca475SIngo Molnar ---help--- 2469e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2470e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2471e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2472e279b6c1SSam Ravnborg 2473e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2474e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2475e279b6c1SSam Ravnborg ---help--- 2476e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2477e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2478e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2479e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2480e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2481e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2482e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2483e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2484e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2485e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2486e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2487e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2488e279b6c1SSam Ravnborg this feature. 2489e279b6c1SSam Ravnborg 2490e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2491dd8af076SLen Brown depends on CPU_IDLE 2492e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 24938f9ca475SIngo Molnar ---help--- 2494e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2495e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2496e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2497e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2498e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2499e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2500e279b6c1SSam Ravnborg this option does nothing.) 2501e279b6c1SSam Ravnborg 2502e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2503e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 25048f9ca475SIngo Molnar ---help--- 2505e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2506e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2507e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2508e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2509e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2510e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2511e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2512e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2513e279b6c1SSam Ravnborg especially if you are using gpm. 2514e279b6c1SSam Ravnborg 2515e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2516e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 25178f9ca475SIngo Molnar ---help--- 2518e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2519e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2520e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2521e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2522e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2523e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2524e279b6c1SSam Ravnborg 2525e279b6c1SSam Ravnborgendif # APM 2526e279b6c1SSam Ravnborg 2527bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2528e279b6c1SSam Ravnborg 2529e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2530e279b6c1SSam Ravnborg 253127471fdbSAndy Henroidsource "drivers/idle/Kconfig" 253227471fdbSAndy Henroid 2533e279b6c1SSam Ravnborgendmenu 2534e279b6c1SSam Ravnborg 2535e279b6c1SSam Ravnborg 2536e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2537e279b6c1SSam Ravnborg 2538e279b6c1SSam Ravnborgconfig PCI 25391ac97018SIngo Molnar bool "PCI support" 25401c858087SAdrian Bunk default y 25418f9ca475SIngo Molnar ---help--- 2542e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2543e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2544e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2545e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2546e279b6c1SSam Ravnborg 2547e279b6c1SSam Ravnborgchoice 2548e279b6c1SSam Ravnborg prompt "PCI access mode" 2549efefa6f6SIngo Molnar depends on X86_32 && PCI 2550e279b6c1SSam Ravnborg default PCI_GOANY 2551e279b6c1SSam Ravnborg ---help--- 2552e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2553e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2554e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2555e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2556e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2557e279b6c1SSam Ravnborg 2558e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2559e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2560e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2561e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2562e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2563e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2564e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2565e279b6c1SSam Ravnborg 2566e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2567e279b6c1SSam Ravnborg bool "BIOS" 2568e279b6c1SSam Ravnborg 2569e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2570e279b6c1SSam Ravnborg bool "MMConfig" 2571e279b6c1SSam Ravnborg 2572e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2573e279b6c1SSam Ravnborg bool "Direct" 2574e279b6c1SSam Ravnborg 25753ef0e1f8SAndres Salomonconfig PCI_GOOLPC 257676fb6570SDaniel Drake bool "OLPC XO-1" 25773ef0e1f8SAndres Salomon depends on OLPC 25783ef0e1f8SAndres Salomon 25792bdd1b03SAndres Salomonconfig PCI_GOANY 25802bdd1b03SAndres Salomon bool "Any" 25812bdd1b03SAndres Salomon 2582e279b6c1SSam Ravnborgendchoice 2583e279b6c1SSam Ravnborg 2584e279b6c1SSam Ravnborgconfig PCI_BIOS 25853c2362e6SHarvey Harrison def_bool y 2586efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2587e279b6c1SSam Ravnborg 2588e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2589e279b6c1SSam Ravnborgconfig PCI_DIRECT 25903c2362e6SHarvey Harrison def_bool y 25910aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2592e279b6c1SSam Ravnborg 2593e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 25943c2362e6SHarvey Harrison def_bool y 25955f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2596e279b6c1SSam Ravnborg 25973ef0e1f8SAndres Salomonconfig PCI_OLPC 25982bdd1b03SAndres Salomon def_bool y 25992bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 26003ef0e1f8SAndres Salomon 2601b5401a96SAlex Nixonconfig PCI_XEN 2602b5401a96SAlex Nixon def_bool y 2603b5401a96SAlex Nixon depends on PCI && XEN 2604b5401a96SAlex Nixon select SWIOTLB_XEN 2605b5401a96SAlex Nixon 2606e279b6c1SSam Ravnborgconfig PCI_DOMAINS 26073c2362e6SHarvey Harrison def_bool y 2608e279b6c1SSam Ravnborg depends on PCI 2609e279b6c1SSam Ravnborg 2610e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2611e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2612e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2613e279b6c1SSam Ravnborg 26143f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 26156a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 26166ea30386SKees Cook depends on PCI 26173f6ea84aSIra W. Snyder help 26183f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 26193f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 26203f6ea84aSIra W. Snyder not have ACPI. 26213f6ea84aSIra W. Snyder 262264a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 262364a5fed6SBjorn Helgaas is known to be incomplete. 262464a5fed6SBjorn Helgaas 262564a5fed6SBjorn Helgaas You should say N unless you know you need this. 262664a5fed6SBjorn Helgaas 2627e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2628e279b6c1SSam Ravnborg 26293a495511SWilliam Breathitt Grayconfig ISA_BUS 26303a495511SWilliam Breathitt Gray bool "ISA-style bus support on modern systems" if EXPERT 26313a495511SWilliam Breathitt Gray select ISA_BUS_API 26323a495511SWilliam Breathitt Gray help 26333a495511SWilliam Breathitt Gray Enables ISA-style drivers on modern systems. This is necessary to 26343a495511SWilliam Breathitt Gray support PC/104 devices on X86_64 platforms. 26353a495511SWilliam Breathitt Gray 26363a495511SWilliam Breathitt Gray If unsure, say N. 26373a495511SWilliam Breathitt Gray 26381c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2639e279b6c1SSam Ravnborgconfig ISA_DMA_API 26401c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26411c00f016SDavid Rientjes default y 26421c00f016SDavid Rientjes help 26431c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26441c00f016SDavid Rientjes If unsure, say Y. 2645e279b6c1SSam Ravnborg 264651e68d05SLinus Torvaldsif X86_32 264751e68d05SLinus Torvalds 2648e279b6c1SSam Ravnborgconfig ISA 2649e279b6c1SSam Ravnborg bool "ISA support" 26508f9ca475SIngo Molnar ---help--- 2651e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2652e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2653e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2654e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2655e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2656e279b6c1SSam Ravnborg 2657e279b6c1SSam Ravnborgconfig EISA 2658e279b6c1SSam Ravnborg bool "EISA support" 2659e279b6c1SSam Ravnborg depends on ISA 2660e279b6c1SSam Ravnborg ---help--- 2661e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2662e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2663e279b6c1SSam Ravnborg 2664e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2665e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2666e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2667e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2668e279b6c1SSam Ravnborg 2669e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2670e279b6c1SSam Ravnborg 2671e279b6c1SSam Ravnborg Otherwise, say N. 2672e279b6c1SSam Ravnborg 2673e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2674e279b6c1SSam Ravnborg 2675e279b6c1SSam Ravnborgconfig SCx200 2676e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26778f9ca475SIngo Molnar ---help--- 2678e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2679e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2680e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2681e279b6c1SSam Ravnborg for other scx200_* drivers. 2682e279b6c1SSam Ravnborg 2683e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2684e279b6c1SSam Ravnborg 2685e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2686e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2687592913ecSJohn Stultz depends on SCx200 2688e279b6c1SSam Ravnborg default y 26898f9ca475SIngo Molnar ---help--- 2690e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2691e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2692e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2693e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2694e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2695e279b6c1SSam Ravnborg 26963ef0e1f8SAndres Salomonconfig OLPC 26973ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 269854008979SThomas Gleixner depends on !X86_PAE 26993c554946SAndres Salomon select GPIOLIB 2700dc3119e7SThomas Gleixner select OF 270145bb1674SDaniel Drake select OF_PROMTREE 2702b4e51854SGrant Likely select IRQ_DOMAIN 27038f9ca475SIngo Molnar ---help--- 27043ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 27053ef0e1f8SAndres Salomon XO hardware. 27063ef0e1f8SAndres Salomon 2707a3128588SDaniel Drakeconfig OLPC_XO1_PM 2708a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 270997c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2710a3128588SDaniel Drake select MFD_CORE 2711bf1ebf00SDaniel Drake ---help--- 271297c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2713bf1ebf00SDaniel Drake 2714cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2715cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2716cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2717cfee9597SDaniel Drake ---help--- 2718cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2719cfee9597SDaniel Drake programmable wakeup source. 2720cfee9597SDaniel Drake 27217feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27227feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2723d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2724ed8e47feSRandy Dunlap depends on INPUT=y 2725d8d01a63SDaniel Drake select POWER_SUPPLY 27267feda8e9SDaniel Drake select GPIO_CS5535 27277feda8e9SDaniel Drake select MFD_CORE 27287feda8e9SDaniel Drake ---help--- 27297feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27307bc74b3dSDaniel Drake - EC-driven system wakeups 27317feda8e9SDaniel Drake - Power button 27327bc74b3dSDaniel Drake - Ebook switch 27332cf2baeaSDaniel Drake - Lid switch 2734e1040ac6SDaniel Drake - AC adapter status updates 2735e1040ac6SDaniel Drake - Battery status updates 27367feda8e9SDaniel Drake 2737a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2738a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2739d8d01a63SDaniel Drake depends on OLPC && ACPI 2740d8d01a63SDaniel Drake select POWER_SUPPLY 2741a0f30f59SDaniel Drake ---help--- 2742a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2743a0f30f59SDaniel Drake - EC-driven system wakeups 2744a0f30f59SDaniel Drake - AC adapter status updates 2745a0f30f59SDaniel Drake - Battery status updates 2746e279b6c1SSam Ravnborg 2747d4f3e350SEd Wildgooseconfig ALIX 2748d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2749d4f3e350SEd Wildgoose select GPIOLIB 2750d4f3e350SEd Wildgoose ---help--- 2751d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2752d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2753d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2754d4f3e350SEd Wildgoose get added here. 2755d4f3e350SEd Wildgoose 2756d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2757d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2758d4f3e350SEd Wildgoose 2759d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2760d4f3e350SEd Wildgoose 2761da4e3302SPhilip Prindevilleconfig NET5501 2762da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2763da4e3302SPhilip Prindeville select GPIOLIB 2764da4e3302SPhilip Prindeville ---help--- 2765da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2766da4e3302SPhilip Prindeville 27673197059aSPhilip A. Prindevilleconfig GEOS 27683197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27693197059aSPhilip A. Prindeville select GPIOLIB 27703197059aSPhilip A. Prindeville depends on DMI 27713197059aSPhilip A. Prindeville ---help--- 27723197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27733197059aSPhilip A. Prindeville 27747d029125SVivien Didelotconfig TS5500 27757d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27767d029125SVivien Didelot depends on MELAN 27777d029125SVivien Didelot select CHECK_SIGNATURE 27787d029125SVivien Didelot select NEW_LEDS 27797d029125SVivien Didelot select LEDS_CLASS 27807d029125SVivien Didelot ---help--- 27817d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27827d029125SVivien Didelot 2783e279b6c1SSam Ravnborgendif # X86_32 2784e279b6c1SSam Ravnborg 278523ac4ae8SAndreas Herrmannconfig AMD_NB 2786e279b6c1SSam Ravnborg def_bool y 27870e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2788e279b6c1SSam Ravnborg 2789e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2790e279b6c1SSam Ravnborg 2791388b78adSAlexandre Bounineconfig RAPIDIO 2792fdf90abcSAlexandre Bounine tristate "RapidIO support" 2793388b78adSAlexandre Bounine depends on PCI 2794388b78adSAlexandre Bounine default n 2795388b78adSAlexandre Bounine help 2796fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2797388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2798388b78adSAlexandre Bounine 2799388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2800388b78adSAlexandre Bounine 2801e3263ab3SDavid Herrmannconfig X86_SYSFB 2802e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2803e3263ab3SDavid Herrmann help 2804e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2805e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2806e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2807e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2808e3263ab3SDavid Herrmann to x86. 2809e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2810e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2811e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2812e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2813e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2814e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2815e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2816e3263ab3SDavid Herrmann 2817e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2818e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2819e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2820e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2821e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2822e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2823e3263ab3SDavid Herrmann incompatible with simplefb. 2824e3263ab3SDavid Herrmann 2825e3263ab3SDavid Herrmann If unsure, say Y. 2826e3263ab3SDavid Herrmann 2827e279b6c1SSam Ravnborgendmenu 2828e279b6c1SSam Ravnborg 2829e279b6c1SSam Ravnborg 2830e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2831e279b6c1SSam Ravnborg 2832e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2833e279b6c1SSam Ravnborg 2834e279b6c1SSam Ravnborgconfig IA32_EMULATION 2835e279b6c1SSam Ravnborg bool "IA32 Emulation" 2836e279b6c1SSam Ravnborg depends on X86_64 283739f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2838d1603990SRandy Dunlap select BINFMT_ELF 2839a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 284039f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28418f9ca475SIngo Molnar ---help--- 28425fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28435fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28445fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2845e279b6c1SSam Ravnborg 2846e279b6c1SSam Ravnborgconfig IA32_AOUT 2847e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28486b213e1bSDavid Woodhouse depends on IA32_EMULATION 28498f9ca475SIngo Molnar ---help--- 2850e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2851e279b6c1SSam Ravnborg 28520bf62763SH. Peter Anvinconfig X86_X32 28536ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28549b54050bSBrian Gerst depends on X86_64 28555fd92e65SH. J. Lu ---help--- 28565fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28575fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28585fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28595fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28605fd92e65SH. J. Lu 28615fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 28625fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 28635fd92e65SH. J. Lu option set. 28645fd92e65SH. J. Lu 2865953fee1dSIngo Molnarconfig COMPAT_32 2866953fee1dSIngo Molnar def_bool y 2867953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2868953fee1dSIngo Molnar select HAVE_UID16 2869953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2870953fee1dSIngo Molnar 2871e279b6c1SSam Ravnborgconfig COMPAT 28723c2362e6SHarvey Harrison def_bool y 28730bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2874e279b6c1SSam Ravnborg 28753120e25eSJan Beulichif COMPAT 2876e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28773120e25eSJan Beulich def_bool y 2878e279b6c1SSam Ravnborg 2879e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28803c2362e6SHarvey Harrison def_bool y 28813120e25eSJan Beulich depends on SYSVIPC 28823120e25eSJan Beulichendif 2883ee009e4aSDavid Howells 2884e279b6c1SSam Ravnborgendmenu 2885e279b6c1SSam Ravnborg 2886e279b6c1SSam Ravnborg 2887e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2888e5beae16SKeith Packard def_bool y 2889e5beae16SKeith Packard depends on X86_32 2890e5beae16SKeith Packard 28914692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28924692d77fSAlessandro Rubini bool 289383125a3aSAlessandro Rubini depends on X86_64 || STA2X11 28944692d77fSAlessandro Rubini 2895f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2896f7219a53SAlessandro Rubini bool 289783125a3aSAlessandro Rubini depends on STA2X11 2898f7219a53SAlessandro Rubini 2899e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2900e585513bSKirill A. Shutemov def_bool y 2901e585513bSKirill A. Shutemov 2902e279b6c1SSam Ravnborgsource "net/Kconfig" 2903e279b6c1SSam Ravnborg 2904e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2905e279b6c1SSam Ravnborg 2906e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2907e279b6c1SSam Ravnborg 2908e279b6c1SSam Ravnborgsource "fs/Kconfig" 2909e279b6c1SSam Ravnborg 2910e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2911e279b6c1SSam Ravnborg 2912e279b6c1SSam Ravnborgsource "security/Kconfig" 2913e279b6c1SSam Ravnborg 2914e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2915e279b6c1SSam Ravnborg 2916edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2917edf88417SAvi Kivity 2918e279b6c1SSam Ravnborgsource "lib/Kconfig" 2919