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 31*f616ab59SChristoph Hellwig select NEED_DMA_MAP_STATE 32d94e0685SIngo Molnar select X86_DEV_DMA_OPS 33f8781c4aSDominik Brodowski select ARCH_HAS_SYSCALL_WRAPPER 341032c0baSSam Ravnborg 35d94e0685SIngo Molnar# 36d94e0685SIngo Molnar# Arch settings 37d94e0685SIngo Molnar# 38d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 39d94e0685SIngo Molnar# ported to 32-bit as well. ) 40d94e0685SIngo Molnar# 418d5fffb9SSam Ravnborgconfig X86 423c2362e6SHarvey Harrison def_bool y 43c763ea26SIngo Molnar # 44c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 45c763ea26SIngo Molnar # 466471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 476e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 486471b825SIngo Molnar select ANON_INODES 496471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 506471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 5191dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 52fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5321266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 546471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5572d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 56316d097cSDave Hansen select ARCH_HAS_FILTER_PGPROT 576974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 58957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 595c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 6010bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 61c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 6239208aa7SKees Cook select ARCH_HAS_REFCOUNT 630aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 64d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 656471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 66ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 67ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 68ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 69c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 7065f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 716471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 726471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 7377fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 745e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 756471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 766471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 776471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 786471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 796471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 80ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 81c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 8238d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 836471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 846471b825SIngo Molnar select CLKEVT_I8253 856471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 866471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 876471b825SIngo Molnar select DCACHE_WORD_ACCESS 88fec777c3SChristoph Hellwig select DMA_DIRECT_OPS 8945471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 9045471cd9SLinus Torvalds select EDAC_SUPPORT 916471b825SIngo Molnar select GENERIC_CLOCKEVENTS 926471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 936471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 946471b825SIngo Molnar select GENERIC_CMOS_UPDATE 956471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 9661dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 976471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 986471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 996471b825SIngo Molnar select GENERIC_IOMAP 100c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 1010fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 102ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1036471b825SIngo Molnar select GENERIC_IRQ_PROBE 104c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1056471b825SIngo Molnar select GENERIC_IRQ_SHOW 1066471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1076471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1086471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1096471b825SIngo Molnar select GENERIC_STRNLEN_USER 1106471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1117edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1126471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1136471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1146471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1156471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1166471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1176471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 118d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1196471b825SIngo Molnar select HAVE_ARCH_KGDB 1209e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1219e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1221b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1236471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 124f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 1256471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1266471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 127a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 128e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 129c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1306471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1316471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1326471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1336471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 134c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1356471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1366471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1376471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1389c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 139677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 14006aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 141c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 14258340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1435f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 144644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1456471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1466471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1476471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1486b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1490067f129SK.Prasad select HAVE_HW_BREAKPOINT 1506471b825SIngo Molnar select HAVE_IDE 1516471b825SIngo Molnar select HAVE_IOREMAP_PROT 1526471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1536471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1546471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1556471b825SIngo Molnar select HAVE_KERNEL_GZIP 1566471b825SIngo Molnar select HAVE_KERNEL_LZ4 1576471b825SIngo Molnar select HAVE_KERNEL_LZMA 1586471b825SIngo Molnar select HAVE_KERNEL_LZO 1596471b825SIngo Molnar select HAVE_KERNEL_XZ 1606471b825SIngo Molnar select HAVE_KPROBES 1616471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 162540adea3SMasami Hiramatsu select HAVE_FUNCTION_ERROR_INJECTION 1636471b825SIngo Molnar select HAVE_KRETPROBES 1646471b825SIngo Molnar select HAVE_KVM 1656471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1666471b825SIngo Molnar select HAVE_MEMBLOCK 1676471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1680102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 169ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 17042a0bb3fSPetr Mladek select HAVE_NMI 1716471b825SIngo Molnar select HAVE_OPROFILE 1726471b825SIngo Molnar select HAVE_OPTPROBES 1736471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1746471b825SIngo Molnar select HAVE_PERF_EVENTS 175c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 17692e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 177c5e63197SJiri Olsa select HAVE_PERF_REGS 178c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1799e52fc2bSVitaly Kuznetsov select HAVE_RCU_TABLE_FREE 1806471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 18111af8474SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION 182c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1836471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1846471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1857c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 186c0185808SThomas Gleixner select IRQ_FORCED_THREADING 18786596f0aSChristoph Hellwig select NEED_SG_DMA_LENGTH 188df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1896471b825SIngo Molnar select PERF_EVENTS 1903195ef59SPrarit Bhargava select RTC_LIB 191d6faca40SArnd Bergmann select RTC_MC146818_LIB 1926471b825SIngo Molnar select SPARSE_IRQ 19383fe27eaSPranith Kumar select SRCU 1946471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 19515f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1966471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1976471b825SIngo Molnar select VIRT_TO_BUS 1986471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1997d8330a5SBalbir Singh 200ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 2013120e25eSJan Beulich def_bool y 2023120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 203ba7e4d13SIngo Molnar 20451b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 20551b26adaSLinus Torvalds string 20651b26adaSLinus Torvalds default "elf32-i386" if X86_32 20751b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 20851b26adaSLinus Torvalds 20973531905SSam Ravnborgconfig ARCH_DEFCONFIG 210b9b39bfbSSam Ravnborg string 21173531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 21273531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 213b9b39bfbSSam Ravnborg 2148d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2153c2362e6SHarvey Harrison def_bool y 2168d5fffb9SSam Ravnborg 2178d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2183c2362e6SHarvey Harrison def_bool y 2198d5fffb9SSam Ravnborg 2208d5fffb9SSam Ravnborgconfig MMU 2213c2362e6SHarvey Harrison def_bool y 2228d5fffb9SSam Ravnborg 2239e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2249e08f57dSDaniel Cashman default 28 if 64BIT 2259e08f57dSDaniel Cashman default 8 2269e08f57dSDaniel Cashman 2279e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2289e08f57dSDaniel Cashman default 32 if 64BIT 2299e08f57dSDaniel Cashman default 16 2309e08f57dSDaniel Cashman 2319e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2329e08f57dSDaniel Cashman default 8 2339e08f57dSDaniel Cashman 2349e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2359e08f57dSDaniel Cashman default 16 2369e08f57dSDaniel Cashman 2378d5fffb9SSam Ravnborgconfig SBUS 2388d5fffb9SSam Ravnborg bool 2398d5fffb9SSam Ravnborg 2408d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2413120e25eSJan Beulich def_bool y 2423120e25eSJan Beulich depends on ISA_DMA_API 2438d5fffb9SSam Ravnborg 2448d5fffb9SSam Ravnborgconfig GENERIC_BUG 2453c2362e6SHarvey Harrison def_bool y 2468d5fffb9SSam Ravnborg depends on BUG 247b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 248b93a531eSJan Beulich 249b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 250b93a531eSJan Beulich bool 2518d5fffb9SSam Ravnborg 2528d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2533c2362e6SHarvey Harrison def_bool y 2548d5fffb9SSam Ravnborg 2558d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2563120e25eSJan Beulich def_bool y 2573120e25eSJan Beulich depends on ISA_DMA_API 2588d5fffb9SSam Ravnborg 2591032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2603120e25eSJan Beulich def_bool y 2611032c0baSSam Ravnborg 2621032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2631032c0baSSam Ravnborg def_bool y 2641032c0baSSam Ravnborg 2659a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2669a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2678d5fffb9SSam Ravnborg 2681b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2691b27d05bSPekka Enberg def_bool y 2701b27d05bSPekka Enberg 271316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT 272316d097cSDave Hansen def_bool y 273316d097cSDave Hansen 274dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 27589c9c4c5SBrian Gerst def_bool y 276b32ef636Stravis@sgi.com 27708fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 27808fc4580STejun Heo def_bool y 27908fc4580STejun Heo 28008fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 28111124411STejun Heo def_bool y 28211124411STejun Heo 283801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 284801e4062SJohannes Berg def_bool y 285801e4062SJohannes Berg 286f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 287f4cb5700SJohannes Berg def_bool y 288f4cb5700SJohannes Berg 289cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 290cfe28c5dSSteve Capper def_bool y 291cfe28c5dSSteve Capper 29253313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 29353313b2cSSteve Capper def_bool y 29453313b2cSSteve Capper 2958d5fffb9SSam Ravnborgconfig ZONE_DMA32 296e0fd24a3SJan Beulich def_bool y if X86_64 2978d5fffb9SSam Ravnborg 2988d5fffb9SSam Ravnborgconfig AUDIT_ARCH 299e0fd24a3SJan Beulich def_bool y if X86_64 3008d5fffb9SSam Ravnborg 301765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 302765c68bdSIngo Molnar def_bool y 303765c68bdSIngo Molnar 3046a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3056a11f75bSAkinobu Mita def_bool y 3066a11f75bSAkinobu Mita 307d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 308d6f2d75aSAndrey Ryabinin hex 309d6f2d75aSAndrey Ryabinin depends on KASAN 310d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 311d6f2d75aSAndrey Ryabinin 31269575d38SShane Wangconfig HAVE_INTEL_TXT 31369575d38SShane Wang def_bool y 3146ea30386SKees Cook depends on INTEL_IOMMU && ACPI 31569575d38SShane Wang 3166b0c3d44SSam Ravnborgconfig X86_32_SMP 3176b0c3d44SSam Ravnborg def_bool y 3186b0c3d44SSam Ravnborg depends on X86_32 && SMP 3196b0c3d44SSam Ravnborg 3206b0c3d44SSam Ravnborgconfig X86_64_SMP 3216b0c3d44SSam Ravnborg def_bool y 3226b0c3d44SSam Ravnborg depends on X86_64 && SMP 3236b0c3d44SSam Ravnborg 324ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 325ccbeed3aSTejun Heo def_bool y 3262bc2f688SKees Cook depends on X86_32 && CC_STACKPROTECTOR_NONE 327ccbeed3aSTejun Heo 3282b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3292b144498SSrikar Dronamraju def_bool y 3302b144498SSrikar Dronamraju 331d20642f0SRob Herringconfig FIX_EARLYCON_MEM 332d20642f0SRob Herring def_bool y 333d20642f0SRob Herring 33498233368SKirill A. Shutemovconfig PGTABLE_LEVELS 33598233368SKirill A. Shutemov int 33677ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 33798233368SKirill A. Shutemov default 4 if X86_64 33898233368SKirill A. Shutemov default 3 if X86_PAE 33998233368SKirill A. Shutemov default 2 34098233368SKirill A. Shutemov 341506f1d07SSam Ravnborgsource "init/Kconfig" 342dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3438d5fffb9SSam Ravnborg 344506f1d07SSam Ravnborgmenu "Processor type and features" 345506f1d07SSam Ravnborg 3465ee71535SRandy Dunlapconfig ZONE_DMA 3475ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3485ee71535SRandy Dunlap default y 3495ee71535SRandy Dunlap help 3505ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3515ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3525ee71535SRandy Dunlap Disable if no such devices will be used. 3535ee71535SRandy Dunlap 3545ee71535SRandy Dunlap If unsure, say Y. 3555ee71535SRandy Dunlap 356506f1d07SSam Ravnborgconfig SMP 357506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 358506f1d07SSam Ravnborg ---help--- 359506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3604a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3614a474157SRobert Graffham than one CPU, say Y. 362506f1d07SSam Ravnborg 3634a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 364506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 365506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3664a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 367506f1d07SSam Ravnborg will run faster if you say N here. 368506f1d07SSam Ravnborg 369506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 370506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 371506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 372506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 373506f1d07SSam Ravnborg 374506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 375506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 376506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 377506f1d07SSam Ravnborg 378395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 379c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 380506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 381506f1d07SSam Ravnborg 382506f1d07SSam Ravnborg If you don't know what to do here, say N. 383506f1d07SSam Ravnborg 3849def39beSJosh Triplettconfig X86_FEATURE_NAMES 3859def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3869def39beSJosh Triplett default y 3879def39beSJosh Triplett ---help--- 3889def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3899def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3909def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3919def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3929def39beSJosh Triplett 3939def39beSJosh Triplett If in doubt, say Y. 3949def39beSJosh Triplett 39506cd9a7dSYinghai Luconfig X86_X2APIC 39606cd9a7dSYinghai Lu bool "Support x2apic" 39719e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 39806cd9a7dSYinghai Lu ---help--- 39906cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40006cd9a7dSYinghai Lu 40106cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 40206cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 40306cd9a7dSYinghai Lu 40406cd9a7dSYinghai Lu If you don't know what to do here, say N. 40506cd9a7dSYinghai Lu 4066695c85bSYinghai Luconfig X86_MPPARSE 4076e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4087a527688SJan Beulich default y 4095ab74722SIngo Molnar depends on X86_LOCAL_APIC 4108f9ca475SIngo Molnar ---help--- 4116695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4126695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4136695c85bSYinghai Lu 414ddd70cf9SJun Nakajimaconfig GOLDFISH 415ddd70cf9SJun Nakajima def_bool y 416ddd70cf9SJun Nakajima depends on X86_GOLDFISH 417ddd70cf9SJun Nakajima 41876b04384SDavid Woodhouseconfig RETPOLINE 41976b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 42076b04384SDavid Woodhouse default y 421d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 42276b04384SDavid Woodhouse help 42376b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 42476b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 42576b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 42676b04384SDavid Woodhouse support for full protection. The kernel may run slower. 42776b04384SDavid Woodhouse 42876b04384SDavid Woodhouse Without compiler support, at least indirect branches in assembler 42976b04384SDavid Woodhouse code are eliminated. Since this includes the syscall entry path, 43076b04384SDavid Woodhouse it is not entirely pointless. 43176b04384SDavid Woodhouse 432f01d7d51SVikas Shivappaconfig INTEL_RDT 433f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 43478e99b4aSFenghua Yu default n 43578e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 43659fe5a77SThomas Gleixner select KERNFS 43778e99b4aSFenghua Yu help 438f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 439f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 440f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 441f01d7d51SVikas Shivappa Architecture Software Developer Manual. 44278e99b4aSFenghua Yu 44378e99b4aSFenghua Yu Say N if unsure. 44478e99b4aSFenghua Yu 4458425091fSRavikiran G Thirumalaiif X86_32 446a0d0bb4dSRandy Dunlapconfig X86_BIGSMP 447a0d0bb4dSRandy Dunlap bool "Support for big SMP systems with more than 8 CPUs" 448a0d0bb4dSRandy Dunlap depends on SMP 449a0d0bb4dSRandy Dunlap ---help--- 450a0d0bb4dSRandy Dunlap This option is needed for the systems that have more than 8 CPUs 451a0d0bb4dSRandy Dunlap 452c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 453c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 454c5c606d9SRavikiran G Thirumalai default y 4558f9ca475SIngo Molnar ---help--- 45606ac8346SIngo Molnar If you disable this option then the kernel will only support 45706ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 45806ac8346SIngo Molnar systems out there.) 45906ac8346SIngo Molnar 4608425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4618425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 462cb7b8023SBen Hutchings Goldfish (Android emulator) 4638425091fSRavikiran G Thirumalai AMD Elan 4648425091fSRavikiran G Thirumalai RDC R-321x SoC 4658425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 46683125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4673f4110a4SThomas Gleixner Moorestown MID devices 46806ac8346SIngo Molnar 46906ac8346SIngo Molnar If you have one of these systems, or if you want to build a 47006ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4718425091fSRavikiran G Thirumalaiendif 47206ac8346SIngo Molnar 4738425091fSRavikiran G Thirumalaiif X86_64 4748425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4758425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4768425091fSRavikiran G Thirumalai default y 4778425091fSRavikiran G Thirumalai ---help--- 4788425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4798425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4808425091fSRavikiran G Thirumalai systems out there.) 4818425091fSRavikiran G Thirumalai 4828425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4838425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 48444b111b5SSteffen Persvold Numascale NumaChip 4858425091fSRavikiran G Thirumalai ScaleMP vSMP 4868425091fSRavikiran G Thirumalai SGI Ultraviolet 4878425091fSRavikiran G Thirumalai 4888425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4898425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4908425091fSRavikiran G Thirumalaiendif 491c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 492c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 49344b111b5SSteffen Persvoldconfig X86_NUMACHIP 49444b111b5SSteffen Persvold bool "Numascale NumaChip" 49544b111b5SSteffen Persvold depends on X86_64 49644b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 49744b111b5SSteffen Persvold depends on NUMA 49844b111b5SSteffen Persvold depends on SMP 49944b111b5SSteffen Persvold depends on X86_X2APIC 500f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 50144b111b5SSteffen Persvold ---help--- 50244b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 50344b111b5SSteffen Persvold enable more than ~168 cores. 50444b111b5SSteffen Persvold If you don't have one of these, you should say N here. 50503b48632SNick Piggin 5066a48565eSIngo Molnarconfig X86_VSMP 507c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5086276a074SBorislav Petkov select HYPERVISOR_GUEST 5096a48565eSIngo Molnar select PARAVIRT 5106a48565eSIngo Molnar depends on X86_64 && PCI 511c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 512ead91d4bSShai Fultheim depends on SMP 5138f9ca475SIngo Molnar ---help--- 5146a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5156a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5166a48565eSIngo Molnar if you have one of these machines. 5176a48565eSIngo Molnar 518c5c606d9SRavikiran G Thirumalaiconfig X86_UV 519c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 520c5c606d9SRavikiran G Thirumalai depends on X86_64 521c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 52254c28d29SJack Steiner depends on NUMA 5231ecb4ae5SAndrew Morton depends on EFI 5249d6c26e7SSuresh Siddha depends on X86_X2APIC 5251222e564SIngo Molnar depends on PCI 526c5c606d9SRavikiran G Thirumalai ---help--- 527c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 528c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 529c5c606d9SRavikiran G Thirumalai 530c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 531c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 532506f1d07SSam Ravnborg 533ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 534ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 535cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 536ddd70cf9SJun Nakajima ---help--- 537ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 538ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 539ddd70cf9SJun Nakajima Goldfish emulator say N here. 540ddd70cf9SJun Nakajima 541c751e17bSThomas Gleixnerconfig X86_INTEL_CE 542c751e17bSThomas Gleixner bool "CE4100 TV platform" 543c751e17bSThomas Gleixner depends on PCI 544c751e17bSThomas Gleixner depends on PCI_GODIRECT 5456084a6e2SJiang Liu depends on X86_IO_APIC 546c751e17bSThomas Gleixner depends on X86_32 547c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 54837bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 549da6b737bSSebastian Andrzej Siewior select OF 550da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 551c751e17bSThomas Gleixner ---help--- 552c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 553c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 554c751e17bSThomas Gleixner boxes and media devices. 555c751e17bSThomas Gleixner 5564cb9b00fSDavid Cohenconfig X86_INTEL_MID 55743605ef1SAlan Cox bool "Intel MID platform support" 55843605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 559edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5601ea7c673SAlan Cox depends on PCI 5613fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5621ea7c673SAlan Cox depends on X86_IO_APIC 5637c9c3a1eSAlan Cox select SFI 5644cb9b00fSDavid Cohen select I2C 5657c9c3a1eSAlan Cox select DW_APB_TIMER 5661ea7c673SAlan Cox select APB_TIMER 5671ea7c673SAlan Cox select INTEL_SCU_IPC 56815a713dfSMika Westerberg select MFD_INTEL_MSIC 5691ea7c673SAlan Cox ---help--- 5704cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5714cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5724cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5731ea7c673SAlan Cox 5744cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5754cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 57643605ef1SAlan Cox 5778bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5788bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5798bbc2a13SBryan O'Donoghue depends on X86_32 5808bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5818bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5828bbc2a13SBryan O'Donoghue depends on X86_TSC 5838bbc2a13SBryan O'Donoghue depends on PCI 5848bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5858bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5868bbc2a13SBryan O'Donoghue select IOSF_MBI 5878bbc2a13SBryan O'Donoghue select INTEL_IMR 5889ab6eb51SAndy Shevchenko select COMMON_CLK 5898bbc2a13SBryan O'Donoghue ---help--- 5908bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5918bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5928bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5938bbc2a13SBryan O'Donoghue 5943d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5953d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 596eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5973d48aab1SMika Westerberg select COMMON_CLK 5980f531431SMathias Nyman select PINCTRL 599eebb3e8dSAndy Shevchenko select IOSF_MBI 6003d48aab1SMika Westerberg ---help--- 6013d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6023d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6030f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6040f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6053d48aab1SMika Westerberg 60692082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 60792082a88SKen Xue bool "AMD ACPI2Platform devices support" 60892082a88SKen Xue depends on ACPI 60992082a88SKen Xue select COMMON_CLK 61092082a88SKen Xue select PINCTRL 61192082a88SKen Xue ---help--- 61292082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 61392082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 61492082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 61592082a88SKen Xue implemented under PINCTRL subsystem. 61692082a88SKen Xue 617ced3ce76SDavid E. Boxconfig IOSF_MBI 618ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 619ced3ce76SDavid E. Box depends on PCI 620ced3ce76SDavid E. Box ---help--- 621ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 622ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 623ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 624ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 625ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 626ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 627ced3ce76SDavid E. Box This list is not meant to be exclusive. 628ced3ce76SDavid E. Box - BayTrail 629ced3ce76SDavid E. Box - Braswell 630ced3ce76SDavid E. Box - Quark 631ced3ce76SDavid E. Box 632ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 633ced3ce76SDavid E. Box 634ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 635ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 636ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 637ed2226bdSDavid E. Box ---help--- 638ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 639ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 640ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 641ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 642ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 643ed2226bdSDavid E. Box device they want to access. 644ed2226bdSDavid E. Box 645ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 646ed2226bdSDavid E. Box 647c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 648c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 649506f1d07SSam Ravnborg depends on X86_32 650c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 651c5c606d9SRavikiran G Thirumalai select M486 652c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 653c5c606d9SRavikiran G Thirumalai ---help--- 654c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 655c5c606d9SRavikiran G Thirumalai as R-8610-(G). 656c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 657c5c606d9SRavikiran G Thirumalai 658e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6599c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6609c398017SIngo Molnar depends on X86_32 && SMP 661c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6628f9ca475SIngo Molnar ---help--- 663b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 664b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 665b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 666b5660ba7SH. Peter Anvin one and will fallback to default. 667d49c4288SYinghai Lu 668c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 669d49c4288SYinghai Lu 670d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6716fc108a0SJan Beulich def_bool y 672d949f36fSLinus Torvalds # MCE code calls memory_failure(): 673d949f36fSLinus Torvalds depends on X86_MCE 674d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 675d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 676d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 677d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 678d949f36fSLinus Torvalds 67983125a3aSAlessandro Rubiniconfig STA2X11 68083125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 68183125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 682b6e05477SChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 68383125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 68483125a3aSAlessandro Rubini select X86_DMA_REMAP 68583125a3aSAlessandro Rubini select SWIOTLB 68683125a3aSAlessandro Rubini select MFD_STA2X11 6870145071bSLinus Walleij select GPIOLIB 68883125a3aSAlessandro Rubini default n 68983125a3aSAlessandro Rubini ---help--- 69083125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 69183125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 69283125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 69383125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 69483125a3aSAlessandro Rubini standard PC machines. 69583125a3aSAlessandro Rubini 69682148d1dSShérabconfig X86_32_IRIS 69782148d1dSShérab tristate "Eurobraille/Iris poweroff module" 69882148d1dSShérab depends on X86_32 69982148d1dSShérab ---help--- 70082148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 70182148d1dSShérab to shut themselves down properly. A special I/O sequence is 70282148d1dSShérab needed to do so, which is what this module does at 70382148d1dSShérab kernel shutdown. 70482148d1dSShérab 70582148d1dSShérab This is only for Iris machines from EuroBraille. 70682148d1dSShérab 70782148d1dSShérab If unused, say N. 70882148d1dSShérab 709ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7103c2362e6SHarvey Harrison def_bool y 7113c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 712a87d0914SKen Chen depends on X86 7138f9ca475SIngo Molnar ---help--- 714506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 715506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 716506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 717506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 718506f1d07SSam Ravnborg 719506f1d07SSam Ravnborg If in doubt, say "Y". 720506f1d07SSam Ravnborg 7216276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7226276a074SBorislav Petkov bool "Linux guest support" 7238f9ca475SIngo Molnar ---help--- 7246276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7256276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7266276a074SBorislav Petkov setup. 727506f1d07SSam Ravnborg 7286276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7296276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 730506f1d07SSam Ravnborg 7316276a074SBorislav Petkovif HYPERVISOR_GUEST 732506f1d07SSam Ravnborg 733e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 734e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7358f9ca475SIngo Molnar ---help--- 736e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 737e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 738e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 739e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 740e61bd94aSEduardo Pereira Habkost 7416276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7426276a074SBorislav Petkov bool "paravirt-ops debugging" 7436276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7446276a074SBorislav Petkov ---help--- 7456276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7466276a074SBorislav Petkov a paravirt_op is missing when it is called. 7476276a074SBorislav Petkov 748b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 749b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7506ea30386SKees Cook depends on PARAVIRT && SMP 751b4ecc126SJeremy Fitzhardinge ---help--- 752b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 753b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 754b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 755b4ecc126SJeremy Fitzhardinge 7564c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7574c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 758b4ecc126SJeremy Fitzhardinge 7594c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 760b4ecc126SJeremy Fitzhardinge 76145e898b7SWaiman Longconfig QUEUED_LOCK_STAT 76245e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 763cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 76445e898b7SWaiman Long ---help--- 76545e898b7SWaiman Long Enable the collection of statistical data on the slowpath 76645e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 76745e898b7SWaiman Long them on debugfs. 76845e898b7SWaiman Long 7696276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7706276a074SBorislav Petkov 7716276a074SBorislav Petkovconfig KVM_GUEST 7726276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7736276a074SBorislav Petkov depends on PARAVIRT 7746276a074SBorislav Petkov select PARAVIRT_CLOCK 7756276a074SBorislav Petkov default y 7766276a074SBorislav Petkov ---help--- 7776276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7786276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7796276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7806276a074SBorislav Petkov underlying device model, the host provides the guest with 7816276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7826276a074SBorislav Petkov 7831e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7841e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7851e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7861e20eb85SSrivatsa Vaddagiri default n 7871e20eb85SSrivatsa Vaddagiri ---help--- 7881e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7891e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7901e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7911e20eb85SSrivatsa Vaddagiri 7926276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7936276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7946276a074SBorislav Petkov depends on PARAVIRT 7956276a074SBorislav Petkov default n 7966276a074SBorislav Petkov ---help--- 7976276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7986276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7996276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8006276a074SBorislav Petkov that, there can be a small performance impact. 8016276a074SBorislav Petkov 8026276a074SBorislav Petkov If in doubt, say N here. 8036276a074SBorislav Petkov 8047af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8057af192c9SGerd Hoffmann bool 8067af192c9SGerd Hoffmann 8074a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8084a362601SJan Kiszka bool "Jailhouse non-root cell support" 809abde587bSArnd Bergmann depends on X86_64 && PCI 81087e65d05SJan Kiszka select X86_PM_TIMER 8114a362601SJan Kiszka ---help--- 8124a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8134a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8144a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8154a362601SJan Kiszka 8166276a074SBorislav Petkovendif #HYPERVISOR_GUEST 81797349135SJeremy Fitzhardinge 81808677214SYinghai Luconfig NO_BOOTMEM 819774ea0bcSYinghai Lu def_bool y 82008677214SYinghai Lu 821506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 822506f1d07SSam Ravnborg 823506f1d07SSam Ravnborgconfig HPET_TIMER 8243c2362e6SHarvey Harrison def_bool X86_64 825506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8268f9ca475SIngo Molnar ---help--- 827506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 828506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 829506f1d07SSam Ravnborg present. 830506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 831506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 832506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8334e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8344e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 835506f1d07SSam Ravnborg 836506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 837506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 838506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 839506f1d07SSam Ravnborg 840506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 841506f1d07SSam Ravnborg 842506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8433c2362e6SHarvey Harrison def_bool y 8449d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 845506f1d07SSam Ravnborg 846bb24c471SJacob Panconfig APB_TIMER 847933b9463SAlan Cox def_bool y if X86_INTEL_MID 848933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 84906c3df49SJamie Iles select DW_APB_TIMER 850a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 851bb24c471SJacob Pan help 852bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 853bb24c471SJacob Pan The APBT provides a stable time base on SMP 854bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 855bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 856bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 857bb24c471SJacob Pan 8586a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 859506f1d07SSam Ravnborg# The code disables itself when not needed. 8607ae9392cSThomas Petazzoniconfig DMI 8617ae9392cSThomas Petazzoni default y 862cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8636a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8648f9ca475SIngo Molnar ---help--- 8657ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8667ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8677ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8687ae9392cSThomas Petazzoni BIOS code. 8697ae9392cSThomas Petazzoni 870506f1d07SSam Ravnborgconfig GART_IOMMU 87138901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 872a4ce5a48SChristoph Hellwig select IOMMU_HELPER 873506f1d07SSam Ravnborg select SWIOTLB 87423ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8758f9ca475SIngo Molnar ---help--- 876ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 877ced3c42cSIngo Molnar GART based hardware IOMMUs. 878ced3c42cSIngo Molnar 879ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 880ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 881ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 882ced3c42cSIngo Molnar 883ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 884ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 885ced3c42cSIngo Molnar 886ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 887ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 888ced3c42cSIngo Molnar 32-bit limited device. 889ced3c42cSIngo Molnar 890ced3c42cSIngo Molnar If unsure, say Y. 891506f1d07SSam Ravnborg 892506f1d07SSam Ravnborgconfig CALGARY_IOMMU 893506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 894a4ce5a48SChristoph Hellwig select IOMMU_HELPER 895506f1d07SSam Ravnborg select SWIOTLB 8966ea30386SKees Cook depends on X86_64 && PCI 8978f9ca475SIngo Molnar ---help--- 898506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 899506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 900506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 901506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 902506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 903506f1d07SSam Ravnborg prevents them from going anywhere except their intended 904506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 905506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 906506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 907506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 908506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 909506f1d07SSam Ravnborg If unsure, say Y. 910506f1d07SSam Ravnborg 911506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9123c2362e6SHarvey Harrison def_bool y 9133c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 914506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9158f9ca475SIngo Molnar ---help--- 916506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 917506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 918506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 919506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 920506f1d07SSam Ravnborg If unsure, say Y. 921506f1d07SSam Ravnborg 922506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 923506f1d07SSam Ravnborgconfig SWIOTLB 924a1afd01cSJoerg Roedel def_bool y if X86_64 925*f616ab59SChristoph Hellwig select NEED_DMA_MAP_STATE 9268f9ca475SIngo Molnar ---help--- 927506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9284454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9294454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9304454d327SJoe Millenbach with more than 3 GB of memory. 9314454d327SJoe Millenbach If unsure, say Y. 932506f1d07SSam Ravnborg 9331184dc2fSMike Travisconfig MAXSMP 934ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9356ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 93636f5101aSMike Travis select CPUMASK_OFFSTACK 9378f9ca475SIngo Molnar ---help--- 938ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9391184dc2fSMike Travis If unsure, say N. 940506f1d07SSam Ravnborg 941aec6487eSIngo Molnar# 942aec6487eSIngo Molnar# The maximum number of CPUs supported: 943aec6487eSIngo Molnar# 944aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 945aec6487eSIngo Molnar# and which can be configured interactively in the 946aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 947aec6487eSIngo Molnar# 948aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on 949aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel. 950aec6487eSIngo Molnar# 951aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable 952aec6487eSIngo Molnar# interactive configuration. ) 953aec6487eSIngo Molnar# 954a0d0bb4dSRandy Dunlap 955aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN 956a0d0bb4dSRandy Dunlap int 957aec6487eSIngo Molnar default NR_CPUS_RANGE_END if MAXSMP 958a0d0bb4dSRandy Dunlap default 1 if !SMP 959a0d0bb4dSRandy Dunlap default 2 960a0d0bb4dSRandy Dunlap 961aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 962a0d0bb4dSRandy Dunlap int 963a0d0bb4dSRandy Dunlap depends on X86_32 964aec6487eSIngo Molnar default 64 if SMP && X86_BIGSMP 965aec6487eSIngo Molnar default 8 if SMP && !X86_BIGSMP 966a0d0bb4dSRandy Dunlap default 1 if !SMP 967a0d0bb4dSRandy Dunlap 968aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 969a0d0bb4dSRandy Dunlap int 970a0d0bb4dSRandy Dunlap depends on X86_64 971aec6487eSIngo Molnar default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 972aec6487eSIngo Molnar default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 973a0d0bb4dSRandy Dunlap default 1 if !SMP 974aec6487eSIngo Molnar 975aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 976aec6487eSIngo Molnar int 977aec6487eSIngo Molnar depends on X86_32 978aec6487eSIngo Molnar default 32 if X86_BIGSMP 979aec6487eSIngo Molnar default 8 if SMP 980aec6487eSIngo Molnar default 1 if !SMP 981aec6487eSIngo Molnar 982aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 983aec6487eSIngo Molnar int 984aec6487eSIngo Molnar depends on X86_64 985a0d0bb4dSRandy Dunlap default 8192 if MAXSMP 986a0d0bb4dSRandy Dunlap default 64 if SMP 987aec6487eSIngo Molnar default 1 if !SMP 988a0d0bb4dSRandy Dunlap 989506f1d07SSam Ravnborgconfig NR_CPUS 99036f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 991aec6487eSIngo Molnar range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 992aec6487eSIngo Molnar default NR_CPUS_DEFAULT 9938f9ca475SIngo Molnar ---help--- 994506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 995bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 996cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 997506f1d07SSam Ravnborg minimum value which makes sense is 2. 998506f1d07SSam Ravnborg 999aec6487eSIngo Molnar This is purely to save memory: each supported CPU adds about 8KB 1000aec6487eSIngo Molnar to the kernel image. 1001506f1d07SSam Ravnborg 1002506f1d07SSam Ravnborgconfig SCHED_SMT 1003506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 1004c8e56d20SBorislav Petkov depends on SMP 10058f9ca475SIngo Molnar ---help--- 1006506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 1007506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 1008506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 1009506f1d07SSam Ravnborg N here. 1010506f1d07SSam Ravnborg 1011506f1d07SSam Ravnborgconfig SCHED_MC 10123c2362e6SHarvey Harrison def_bool y 10133c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 1014c8e56d20SBorislav Petkov depends on SMP 10158f9ca475SIngo Molnar ---help--- 1016506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 1017506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 1018506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 1019506f1d07SSam Ravnborg 1020de966cf4STim Chenconfig SCHED_MC_PRIO 1021de966cf4STim Chen bool "CPU core priorities scheduler support" 10220a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 10230a21fc12SIngo Molnar select X86_INTEL_PSTATE 10240a21fc12SIngo Molnar select CPU_FREQ 1025de966cf4STim Chen default y 10265e76b2abSTim Chen ---help--- 1027de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1028de966cf4STim Chen core ordering determined at manufacturing time, which allows 1029de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1030de966cf4STim Chen single threaded workloads) than others. 1031de966cf4STim Chen 1032de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1033de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1034de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1035de966cf4STim Chen overall system performance can be achieved. 1036de966cf4STim Chen 1037de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1038de966cf4STim Chen 1039de966cf4STim Chen If unsure say Y here. 10405e76b2abSTim Chen 1041506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 1042506f1d07SSam Ravnborg 104330b8b006SThomas Gleixnerconfig UP_LATE_INIT 104430b8b006SThomas Gleixner def_bool y 1045ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 104630b8b006SThomas Gleixner 1047506f1d07SSam Ravnborgconfig X86_UP_APIC 104850849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 104950849eefSJan Beulich default PCI_MSI 105038a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10518f9ca475SIngo Molnar ---help--- 1052506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1053506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1054506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1055506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1056506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1057506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1058506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1059506f1d07SSam Ravnborg lockups. 1060506f1d07SSam Ravnborg 1061506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1062506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1063506f1d07SSam Ravnborg depends on X86_UP_APIC 10648f9ca475SIngo Molnar ---help--- 1065506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1066506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1067506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1068506f1d07SSam Ravnborg 1069506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1070506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1071506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1072506f1d07SSam Ravnborg 1073506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10743c2362e6SHarvey Harrison def_bool y 10750dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1076b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 107752f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1078506f1d07SSam Ravnborg 1079506f1d07SSam Ravnborgconfig X86_IO_APIC 1080b1da1e71SJan Beulich def_bool y 1081b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1082506f1d07SSam Ravnborg 108341b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 108441b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 108541b9eb26SStefan Assmann depends on X86_IO_APIC 10868f9ca475SIngo Molnar ---help--- 108741b9eb26SStefan Assmann This option enables a workaround that fixes a source of 108841b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 108941b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 109041b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 109141b9eb26SStefan Assmann 109241b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 109341b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 109441b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 109541b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 109641b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 109741b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 109841b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 109941b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 110041b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 110141b9eb26SStefan Assmann down (vital) interrupt lines. 110241b9eb26SStefan Assmann 110341b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 110441b9eb26SStefan Assmann increased on these systems. 110541b9eb26SStefan Assmann 1106506f1d07SSam Ravnborgconfig X86_MCE 1107bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1108648ed940SChen, Gong select GENERIC_ALLOCATOR 1109e57dbaf7SBorislav Petkov default y 1110506f1d07SSam Ravnborg ---help--- 1111bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1112bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1113506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1114bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 11154efc0670SAndi Kleen 11165de97c9fSTony Luckconfig X86_MCELOG_LEGACY 11175de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 11185de97c9fSTony Luck depends on X86_MCE 11195de97c9fSTony Luck ---help--- 11205de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 11215de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 11225de97c9fSTony Luck rasdaemon solution. 11235de97c9fSTony Luck 1124506f1d07SSam Ravnborgconfig X86_MCE_INTEL 11253c2362e6SHarvey Harrison def_bool y 11263c2362e6SHarvey Harrison prompt "Intel MCE features" 1127c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 11288f9ca475SIngo Molnar ---help--- 1129506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1130506f1d07SSam Ravnborg the thermal monitor. 1131506f1d07SSam Ravnborg 1132506f1d07SSam Ravnborgconfig X86_MCE_AMD 11333c2362e6SHarvey Harrison def_bool y 11343c2362e6SHarvey Harrison prompt "AMD MCE features" 1135f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11368f9ca475SIngo Molnar ---help--- 1137506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1138506f1d07SSam Ravnborg the DRAM Error Threshold. 1139506f1d07SSam Ravnborg 11404efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11416fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1142c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11434efc0670SAndi Kleen ---help--- 11444efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11455065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11464efc0670SAndi Kleen line. 11474efc0670SAndi Kleen 1148b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1149b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11506fc108a0SJan Beulich def_bool y 1151b2762686SAndi Kleen 1152ea149b36SAndi Kleenconfig X86_MCE_INJECT 1153bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1154ea149b36SAndi Kleen tristate "Machine check injector support" 1155ea149b36SAndi Kleen ---help--- 1156ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1157ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1158ea149b36SAndi Kleen QA it is safe to say n. 1159ea149b36SAndi Kleen 11604efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11614efc0670SAndi Kleen def_bool y 11625bb38adcSAndi Kleen depends on X86_MCE_INTEL 11634efc0670SAndi Kleen 116407dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1165e633c65aSKan Liang 11665aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11671e642812SIngo Molnar bool "Legacy VM86 support" 11685aef51c3SAndy Lutomirski default n 1169506f1d07SSam Ravnborg depends on X86_32 11708f9ca475SIngo Molnar ---help--- 11715aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11725aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11735aef51c3SAndy Lutomirski 11745aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11755aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11765aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11775aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11785aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11791e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11801e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11811e642812SIngo Molnar mode might be faster than emulation and you might want to 11821e642812SIngo Molnar enable this option. 11835aef51c3SAndy Lutomirski 11841e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11851e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11861e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11871e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11885aef51c3SAndy Lutomirski 11891e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11901e642812SIngo Molnar and slows down exception handling a tiny bit. 11915aef51c3SAndy Lutomirski 11921e642812SIngo Molnar If unsure, say N here. 11935aef51c3SAndy Lutomirski 11945aef51c3SAndy Lutomirskiconfig VM86 11955aef51c3SAndy Lutomirski bool 11965aef51c3SAndy Lutomirski default X86_LEGACY_VM86 119734273f41SH. Peter Anvin 119834273f41SH. Peter Anvinconfig X86_16BIT 119934273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 120034273f41SH. Peter Anvin default y 1201a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 120234273f41SH. Peter Anvin ---help--- 120334273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 120434273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 120534273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 120634273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 120734273f41SH. Peter Anvin 120834273f41SH. Peter Anvinconfig X86_ESPFIX32 120934273f41SH. Peter Anvin def_bool y 121034273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1211506f1d07SSam Ravnborg 1212197725deSH. Peter Anvinconfig X86_ESPFIX64 1213197725deSH. Peter Anvin def_bool y 121434273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1215506f1d07SSam Ravnborg 12161ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 12171ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 12181ad83c85SAndy Lutomirski default y 12191ad83c85SAndy Lutomirski depends on X86_64 12201ad83c85SAndy Lutomirski ---help--- 12211ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 12221ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 12231ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 12241ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 12251ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 12261ad83c85SAndy Lutomirski 0xffffffffff600?00. 12271ad83c85SAndy Lutomirski 12281ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12291ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12301ad83c85SAndy Lutomirski 12311ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12321ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12331ad83c85SAndy Lutomirski 1234506f1d07SSam Ravnborgconfig TOSHIBA 1235506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1236506f1d07SSam Ravnborg depends on X86_32 1237506f1d07SSam Ravnborg ---help--- 1238506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1239506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1240506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1241506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1242506f1d07SSam Ravnborg 1243506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1244506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1245506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1246506f1d07SSam Ravnborg 1247506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1248506f1d07SSam Ravnborg Say N otherwise. 1249506f1d07SSam Ravnborg 1250506f1d07SSam Ravnborgconfig I8K 1251039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1252949a9d70SJean Delvare select HWMON 1253039ae585SPali Rohár select SENSORS_DELL_SMM 1254506f1d07SSam Ravnborg ---help--- 1255039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1256039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1257039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1258039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1259039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1260039ae585SPali Rohár needed userspace package i8kutils. 1261506f1d07SSam Ravnborg 1262039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1263039ae585SPali Rohár use userspace package i8kutils. 1264506f1d07SSam Ravnborg Say N otherwise. 1265506f1d07SSam Ravnborg 1266506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12679ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12689ba16087SJan Beulich depends on X86_32 1269506f1d07SSam Ravnborg ---help--- 1270506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1271506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1272506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1273506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1274506f1d07SSam Ravnborg system. 1275506f1d07SSam Ravnborg 1276506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12775e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1278506f1d07SSam Ravnborg 1279506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1280506f1d07SSam Ravnborg enable this option even if you don't need it. 1281506f1d07SSam Ravnborg Say N otherwise. 1282506f1d07SSam Ravnborg 1283506f1d07SSam Ravnborgconfig MICROCODE 12849a2bc335SBorislav Petkov bool "CPU microcode loading support" 12859a2bc335SBorislav Petkov default y 128680030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1287506f1d07SSam Ravnborg select FW_LOADER 1288506f1d07SSam Ravnborg ---help--- 1289506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12905f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12915f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12925f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12935f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12945f9c01aaSBorislav Petkov the Linux kernel. 1295506f1d07SSam Ravnborg 12965f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12971897a969SJaak Ristioja in Documentation/x86/microcode.txt. For that you need to enable 12985f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12995f9c01aaSBorislav Petkov initrd for microcode blobs. 1300506f1d07SSam Ravnborg 1301c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1302c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1303c508c46eSBenjamin Gilbert config option. 1304506f1d07SSam Ravnborg 13058d86f390SPeter Orubaconfig MICROCODE_INTEL 1306e43f6e67SBorislav Petkov bool "Intel microcode loading support" 13078d86f390SPeter Oruba depends on MICROCODE 13088d86f390SPeter Oruba default MICROCODE 13098d86f390SPeter Oruba select FW_LOADER 13108f9ca475SIngo Molnar ---help--- 13118d86f390SPeter Oruba This options enables microcode patch loading support for Intel 13128d86f390SPeter Oruba processors. 13138d86f390SPeter Oruba 1314b8989db9SAlan For the current Intel microcode data package go to 1315b8989db9SAlan <https://downloadcenter.intel.com> and search for 1316b8989db9SAlan 'Linux Processor Microcode Data File'. 13178d86f390SPeter Oruba 131880cc9f10SPeter Orubaconfig MICROCODE_AMD 1319e43f6e67SBorislav Petkov bool "AMD microcode loading support" 132080cc9f10SPeter Oruba depends on MICROCODE 132180cc9f10SPeter Oruba select FW_LOADER 13228f9ca475SIngo Molnar ---help--- 132380cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 132480cc9f10SPeter Oruba processors will be enabled. 132580cc9f10SPeter Oruba 1326506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 13273c2362e6SHarvey Harrison def_bool y 1328506f1d07SSam Ravnborg depends on MICROCODE 1329506f1d07SSam Ravnborg 1330506f1d07SSam Ravnborgconfig X86_MSR 1331506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13328f9ca475SIngo Molnar ---help--- 1333506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1334506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1335506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1336506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1337506f1d07SSam Ravnborg systems. 1338506f1d07SSam Ravnborg 1339506f1d07SSam Ravnborgconfig X86_CPUID 1340506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13418f9ca475SIngo Molnar ---help--- 1342506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1343506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1344506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1345506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1346506f1d07SSam Ravnborg 1347506f1d07SSam Ravnborgchoice 1348506f1d07SSam Ravnborg prompt "High Memory Support" 13496fc108a0SJan Beulich default HIGHMEM4G 1350506f1d07SSam Ravnborg depends on X86_32 1351506f1d07SSam Ravnborg 1352506f1d07SSam Ravnborgconfig NOHIGHMEM 1353506f1d07SSam Ravnborg bool "off" 1354506f1d07SSam Ravnborg ---help--- 1355506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1356506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1357506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1358506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1359506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1360506f1d07SSam Ravnborg "high memory". 1361506f1d07SSam Ravnborg 1362506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1363506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1364506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1365506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1366506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1367506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1368506f1d07SSam Ravnborg possible. 1369506f1d07SSam Ravnborg 1370506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1371506f1d07SSam Ravnborg answer "4GB" here. 1372506f1d07SSam Ravnborg 1373506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1374506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1375506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1376506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1377506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1378506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1379506f1d07SSam Ravnborg 1380506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1381506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1382506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1383506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1384506f1d07SSam Ravnborg kernel at boot time.) 1385506f1d07SSam Ravnborg 1386506f1d07SSam Ravnborg If unsure, say "off". 1387506f1d07SSam Ravnborg 1388506f1d07SSam Ravnborgconfig HIGHMEM4G 1389506f1d07SSam Ravnborg bool "4GB" 13908f9ca475SIngo Molnar ---help--- 1391506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1392506f1d07SSam Ravnborg gigabytes of physical RAM. 1393506f1d07SSam Ravnborg 1394506f1d07SSam Ravnborgconfig HIGHMEM64G 1395506f1d07SSam Ravnborg bool "64GB" 139669b8d3fcSMatthew Whitehead depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1397506f1d07SSam Ravnborg select X86_PAE 13988f9ca475SIngo Molnar ---help--- 1399506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1400506f1d07SSam Ravnborg gigabytes of physical RAM. 1401506f1d07SSam Ravnborg 1402506f1d07SSam Ravnborgendchoice 1403506f1d07SSam Ravnborg 1404506f1d07SSam Ravnborgchoice 14056a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1406506f1d07SSam Ravnborg default VMSPLIT_3G 1407506f1d07SSam Ravnborg depends on X86_32 14088f9ca475SIngo Molnar ---help--- 1409506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1410506f1d07SSam Ravnborg 1411506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1412506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1413506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1414506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1415506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1416506f1d07SSam Ravnborg available to user programs, making the address space there 1417506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1418506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1419506f1d07SSam Ravnborg kernel modules. 1420506f1d07SSam Ravnborg 1421506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1422506f1d07SSam Ravnborg option alone! 1423506f1d07SSam Ravnborg 1424506f1d07SSam Ravnborg config VMSPLIT_3G 1425506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1426506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1427506f1d07SSam Ravnborg depends on !X86_PAE 1428506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1429506f1d07SSam Ravnborg config VMSPLIT_2G 1430506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1431506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1432506f1d07SSam Ravnborg depends on !X86_PAE 1433506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1434506f1d07SSam Ravnborg config VMSPLIT_1G 1435506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1436506f1d07SSam Ravnborgendchoice 1437506f1d07SSam Ravnborg 1438506f1d07SSam Ravnborgconfig PAGE_OFFSET 1439506f1d07SSam Ravnborg hex 1440506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1441506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1442506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1443506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1444506f1d07SSam Ravnborg default 0xC0000000 1445506f1d07SSam Ravnborg depends on X86_32 1446506f1d07SSam Ravnborg 1447506f1d07SSam Ravnborgconfig HIGHMEM 14483c2362e6SHarvey Harrison def_bool y 1449506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1450506f1d07SSam Ravnborg 1451506f1d07SSam Ravnborgconfig X86_PAE 14529ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1453506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 14549d99c712SChristian Melki select SWIOTLB 14558f9ca475SIngo Molnar ---help--- 1456506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1457506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1458506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1459506f1d07SSam Ravnborg consumes more pagetable space per process. 1460506f1d07SSam Ravnborg 146177ef56e4SKirill A. Shutemovconfig X86_5LEVEL 146277ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 1463eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 1464162434e7SKirill A. Shutemov select SPARSEMEM_VMEMMAP 146577ef56e4SKirill A. Shutemov depends on X86_64 146677ef56e4SKirill A. Shutemov ---help--- 146777ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 146877ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 146977ef56e4SKirill A. Shutemov physical address space. 147077ef56e4SKirill A. Shutemov 147177ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 147277ef56e4SKirill A. Shutemov 14736657fca0SKirill A. Shutemov A kernel with the option enabled can be booted on machines that 14746657fca0SKirill A. Shutemov support 4- or 5-level paging. 147577ef56e4SKirill A. Shutemov 147677ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 147777ef56e4SKirill A. Shutemov information. 147877ef56e4SKirill A. Shutemov 147977ef56e4SKirill A. Shutemov Say N if unsure. 148077ef56e4SKirill A. Shutemov 1481600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14823120e25eSJan Beulich def_bool y 14833120e25eSJan Beulich depends on X86_64 || X86_PAE 1484600715dcSJeremy Fitzhardinge 148566f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14863120e25eSJan Beulich def_bool y 14873120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 148866f2b061SFUJITA Tomonori 148910971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1490e5008abeSLuis R. Rodriguez def_bool y 14914675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 14928f9ca475SIngo Molnar ---help--- 149310971ab2SIngo Molnar Certain kernel features effectively disable kernel 149410971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 149510971ab2SIngo Molnar supports them), so don't confuse the user by printing 149610971ab2SIngo Molnar that we have them enabled. 14979e899816SNick Piggin 14987744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 14997744ccdbSTom Lendacky def_bool y 15007744ccdbSTom Lendacky 15017744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 15027744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 15037744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 15047744ccdbSTom Lendacky ---help--- 15057744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 15067744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 15077744ccdbSTom Lendacky Encryption (SME). 15087744ccdbSTom Lendacky 15097744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 15107744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 15117744ccdbSTom Lendacky default y 15127744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 15137744ccdbSTom Lendacky ---help--- 15147744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 15157744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 15167744ccdbSTom Lendacky 15177744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 15187744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 15197744ccdbSTom Lendacky 15207744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 15217744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 15227744ccdbSTom Lendacky 1523f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1524f88a68faSTom Lendacky def_bool y 1525f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1526f88a68faSTom Lendacky 1527506f1d07SSam Ravnborg# Common NUMA Features 1528506f1d07SSam Ravnborgconfig NUMA 1529fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1530506f1d07SSam Ravnborg depends on SMP 1531b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1532b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15338f9ca475SIngo Molnar ---help--- 1534506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1535fd51b2d7SKOSAKI Motohiro 1536506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1537506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1538506f1d07SSam Ravnborg NUMA awareness to the kernel. 1539506f1d07SSam Ravnborg 1540c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1541fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1542fd51b2d7SKOSAKI Motohiro 1543b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15447cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1545fd51b2d7SKOSAKI Motohiro 1546fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1547506f1d07SSam Ravnborg 1548eec1d4faSHans Rosenfeldconfig AMD_NUMA 15493c2362e6SHarvey Harrison def_bool y 15503c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15515da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15528f9ca475SIngo Molnar ---help--- 1553eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1554eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1555eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1556eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1557eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1558506f1d07SSam Ravnborg 1559506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15603c2362e6SHarvey Harrison def_bool y 15613c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1562506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1563506f1d07SSam Ravnborg select ACPI_NUMA 15648f9ca475SIngo Molnar ---help--- 1565506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1566506f1d07SSam Ravnborg 15676ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15686ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15696ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15706ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15716ec6e0d9SSuresh Siddha# for details. 15726ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15736ec6e0d9SSuresh Siddha def_bool y 15746ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15756ec6e0d9SSuresh Siddha 1576506f1d07SSam Ravnborgconfig NUMA_EMU 1577506f1d07SSam Ravnborg bool "NUMA emulation" 15781b7e03efSTejun Heo depends on NUMA 15798f9ca475SIngo Molnar ---help--- 1580506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1581506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1582506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1583506f1d07SSam Ravnborg 1584506f1d07SSam Ravnborgconfig NODES_SHIFT 1585d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 158651591e31SDavid Rientjes range 1 10 158751591e31SDavid Rientjes default "10" if MAXSMP 1588506f1d07SSam Ravnborg default "6" if X86_64 1589506f1d07SSam Ravnborg default "3" 1590506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15918f9ca475SIngo Molnar ---help--- 15921184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1593692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1594506f1d07SSam Ravnborg 1595506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15963c2362e6SHarvey Harrison def_bool y 1597506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1598506f1d07SSam Ravnborg 1599506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1600506f1d07SSam Ravnborg def_bool y 16013b16651fSTejun Heo depends on X86_32 && !NUMA 1602506f1d07SSam Ravnborg 1603506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1604506f1d07SSam Ravnborg def_bool y 1605b263295dSChristoph Lameter depends on NUMA && X86_32 1606506f1d07SSam Ravnborg 1607506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1608506f1d07SSam Ravnborg def_bool y 1609b263295dSChristoph Lameter depends on NUMA && X86_32 1610b263295dSChristoph Lameter 1611506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1612506f1d07SSam Ravnborg def_bool y 16136ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1614506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1615506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1616506f1d07SSam Ravnborg 16173b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 16183b16651fSTejun Heo def_bool y 16193b16651fSTejun Heo depends on X86_64 16203b16651fSTejun Heo 1621506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1622506f1d07SSam Ravnborg def_bool y 1623b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1624506f1d07SSam Ravnborg 1625506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1626a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16273120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1628a0842b70SToshi Kani help 1629a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1630a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1631a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1632506f1d07SSam Ravnborg 16333b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16343b16651fSTejun Heo def_bool y 16353b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16363b16651fSTejun Heo 1637a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1638a29815a3SAvi Kivity hex 1639a29815a3SAvi Kivity default 0 if X86_32 1640a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1641a29815a3SAvi Kivity 1642506f1d07SSam Ravnborgsource "mm/Kconfig" 1643506f1d07SSam Ravnborg 16447a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16457a67832cSDan Williams bool 16467a67832cSDan Williams 1647ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16487a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16499f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16509f53f9faSDan Williams depends on BLK_DEV 16517a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16529f53f9faSDan Williams select LIBNVDIMM 1653ec776ef6SChristoph Hellwig help 1654ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1655ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1656ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1657ec776ef6SChristoph Hellwig they can be used for persistent storage. 1658ec776ef6SChristoph Hellwig 1659ec776ef6SChristoph Hellwig Say Y if unsure. 1660ec776ef6SChristoph Hellwig 1661506f1d07SSam Ravnborgconfig HIGHPTE 1662506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16636fc108a0SJan Beulich depends on HIGHMEM 16648f9ca475SIngo Molnar ---help--- 1665506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1666506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1667506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1668506f1d07SSam Ravnborg entries in high memory. 1669506f1d07SSam Ravnborg 16709f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16719f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16728f9ca475SIngo Molnar ---help--- 16739f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16749f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16759f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16769f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16779f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16789f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16799f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16808c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16819f077871SJeremy Fitzhardinge 16829f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16839f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16849f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16859f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16869f077871SJeremy Fitzhardinge 16879f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16889f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16899f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16909f077871SJeremy Fitzhardinge memory. 16919f077871SJeremy Fitzhardinge 1692c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1693c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1694c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1695c885df50SJeremy Fitzhardinge default y 16968f9ca475SIngo Molnar ---help--- 1697c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1698c885df50SJeremy Fitzhardinge on or off. 1699c885df50SJeremy Fitzhardinge 17009ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1701d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1702d0cd7425SH. Peter Anvin default 64 1703d0cd7425SH. Peter Anvin range 4 640 17048f9ca475SIngo Molnar ---help--- 1705d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1706fc381519SIngo Molnar 1707d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1708d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1709fc381519SIngo Molnar 1710d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1711d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1712d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1713d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1714fc381519SIngo Molnar 1715d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1716d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1717d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1718d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1719d0cd7425SH. Peter Anvin entire low memory range. 1720d0cd7425SH. Peter Anvin 1721d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1722d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1723d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1724d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1725d0cd7425SH. Peter Anvin typical corruption patterns. 1726d0cd7425SH. Peter Anvin 1727d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1728fc381519SIngo Molnar 1729506f1d07SSam Ravnborgconfig MATH_EMULATION 1730506f1d07SSam Ravnborg bool 1731a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1732506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1733506f1d07SSam Ravnborg ---help--- 1734506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1735506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1736506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1737506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1738506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1739506f1d07SSam Ravnborg coprocessor or this emulation. 1740506f1d07SSam Ravnborg 1741506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1742506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1743506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1744506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1745506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1746506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1747506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1748506f1d07SSam Ravnborg intend to use this kernel on different machines. 1749506f1d07SSam Ravnborg 1750506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1751506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1752506f1d07SSam Ravnborg 1753506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1754506f1d07SSam Ravnborg kernel, it won't hurt. 1755506f1d07SSam Ravnborg 1756506f1d07SSam Ravnborgconfig MTRR 17576fc108a0SJan Beulich def_bool y 17586a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1759506f1d07SSam Ravnborg ---help--- 1760506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1761506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1762506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1763506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1764506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1765506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1766506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1767506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1768506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1769506f1d07SSam Ravnborg 1770506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1771506f1d07SSam Ravnborg control registers on other processors can be easily supported 1772506f1d07SSam Ravnborg as well: 1773506f1d07SSam Ravnborg 1774506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1775506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1776506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1777506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1778506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1779506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1780506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1781506f1d07SSam Ravnborg 1782506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1783506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1784506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1785506f1d07SSam Ravnborg 1786506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1787506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1788506f1d07SSam Ravnborg 17897225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1790506f1d07SSam Ravnborg 179195ffa243SYinghai Luconfig MTRR_SANITIZER 17922ffb3501SYinghai Lu def_bool y 179395ffa243SYinghai Lu prompt "MTRR cleanup support" 179495ffa243SYinghai Lu depends on MTRR 17958f9ca475SIngo Molnar ---help--- 1796aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1797aba3728cSThomas Gleixner add writeback entries. 179895ffa243SYinghai Lu 1799aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1800692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1801aba3728cSThomas Gleixner mtrr_chunk_size. 180295ffa243SYinghai Lu 18032ffb3501SYinghai Lu If unsure, say Y. 180495ffa243SYinghai Lu 180595ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1806f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1807f5098d62SYinghai Lu range 0 1 1808f5098d62SYinghai Lu default "0" 180995ffa243SYinghai Lu depends on MTRR_SANITIZER 18108f9ca475SIngo Molnar ---help--- 1811f5098d62SYinghai Lu Enable mtrr cleanup default value 181295ffa243SYinghai Lu 181312031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 181412031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 181512031a62SYinghai Lu range 0 7 181612031a62SYinghai Lu default "1" 181712031a62SYinghai Lu depends on MTRR_SANITIZER 18188f9ca475SIngo Molnar ---help--- 181912031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1820aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 182112031a62SYinghai Lu 18222e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 18236fc108a0SJan Beulich def_bool y 18246a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 18252a8a2719SIngo Molnar depends on MTRR 18268f9ca475SIngo Molnar ---help--- 18272e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1828042b78e4SVenki Pallipadi 18292e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18302e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18312e5d9c85Svenkatesh.pallipadi@intel.com 18322e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1833042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18342e5d9c85Svenkatesh.pallipadi@intel.com 18352e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18362e5d9c85Svenkatesh.pallipadi@intel.com 183746cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 183846cf98cdSVenkatesh Pallipadi def_bool y 183946cf98cdSVenkatesh Pallipadi depends on X86_PAT 184046cf98cdSVenkatesh Pallipadi 1841628c6246SH. Peter Anvinconfig ARCH_RANDOM 1842628c6246SH. Peter Anvin def_bool y 1843628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1844628c6246SH. Peter Anvin ---help--- 1845628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1846628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1847628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1848628c6246SH. Peter Anvin secure hardware random number generator. 1849628c6246SH. Peter Anvin 185051ae4a2dSH. Peter Anvinconfig X86_SMAP 185151ae4a2dSH. Peter Anvin def_bool y 185251ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 185351ae4a2dSH. Peter Anvin ---help--- 185451ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 185551ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 185651ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 185751ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 185851ae4a2dSH. Peter Anvin 185951ae4a2dSH. Peter Anvin If unsure, say Y. 186051ae4a2dSH. Peter Anvin 1861aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1862796ebc81SRicardo Neri def_bool y 1863aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1864aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1865aa35f896SRicardo Neri ---help--- 1866aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1867aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1868796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1869796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1870796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1871796ebc81SRicardo Neri 1872796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1873796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1874796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1875796ebc81SRicardo Neri results are dummy. 1876aa35f896SRicardo Neri 187772e9b5feSDave Hansenconfig X86_INTEL_MPX 187872e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 187972e9b5feSDave Hansen def_bool n 1880df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1881df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1882df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 188372e9b5feSDave Hansen ---help--- 188472e9b5feSDave Hansen MPX provides hardware features that can be used in 188572e9b5feSDave Hansen conjunction with compiler-instrumented code to check 188672e9b5feSDave Hansen memory references. It is designed to detect buffer 188772e9b5feSDave Hansen overflow or underflow bugs. 188872e9b5feSDave Hansen 188972e9b5feSDave Hansen This option enables running applications which are 189072e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 189172e9b5feSDave Hansen itself inside the kernel or to protect the kernel 189272e9b5feSDave Hansen against bad memory references. 189372e9b5feSDave Hansen 189472e9b5feSDave Hansen Enabling this option will make the kernel larger: 189572e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 189672e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 189772e9b5feSDave Hansen will increase the kernel memory overhead of each 189872e9b5feSDave Hansen process and adds some branches to paths used during 189972e9b5feSDave Hansen exec() and munmap(). 190072e9b5feSDave Hansen 190172e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 190272e9b5feSDave Hansen 190372e9b5feSDave Hansen If unsure, say N. 190472e9b5feSDave Hansen 190535e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1906284244a9SDave Hansen prompt "Intel Memory Protection Keys" 190735e97790SDave Hansen def_bool y 1908284244a9SDave Hansen # Note: only available in 64-bit mode 190935e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 191052c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 191152c8e601SIngo Molnar select ARCH_HAS_PKEYS 1912284244a9SDave Hansen ---help--- 1913284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1914284244a9SDave Hansen page-based protections, but without requiring modification of the 1915284244a9SDave Hansen page tables when an application changes protection domains. 1916284244a9SDave Hansen 1917284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1918284244a9SDave Hansen 1919284244a9SDave Hansen If unsure, say y. 192035e97790SDave Hansen 1921506f1d07SSam Ravnborgconfig EFI 19229ba16087SJan Beulich bool "EFI runtime service support" 19235b83683fSHuang, Ying depends on ACPI 1924f6ce5002SSergey Vlasov select UCS2_STRING 1925022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1926506f1d07SSam Ravnborg ---help--- 19278b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1928506f1d07SSam Ravnborg available (such as the EFI variable services). 1929506f1d07SSam Ravnborg 19308b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19318b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19328b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19338b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19348b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19358b2cb7a8SHuang, Ying platforms. 1936506f1d07SSam Ravnborg 1937291f3632SMatt Flemingconfig EFI_STUB 1938291f3632SMatt Fleming bool "EFI stub support" 1939b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19407b2a583aSMatt Fleming select RELOCATABLE 1941291f3632SMatt Fleming ---help--- 1942291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1943291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1944291f3632SMatt Fleming 19454172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19460c759662SMatt Fleming 19477d453eeeSMatt Flemingconfig EFI_MIXED 19487d453eeeSMatt Fleming bool "EFI mixed-mode support" 19497d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19507d453eeeSMatt Fleming ---help--- 19517d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19527d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19537d453eeeSMatt Fleming mode. 19547d453eeeSMatt Fleming 19557d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19567d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19577d453eeeSMatt Fleming the EFI handover protocol must be used. 19587d453eeeSMatt Fleming 19597d453eeeSMatt Fleming If unsure, say N. 19607d453eeeSMatt Fleming 1961506f1d07SSam Ravnborgconfig SECCOMP 19623c2362e6SHarvey Harrison def_bool y 19633c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19648f9ca475SIngo Molnar ---help--- 1965506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1966506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1967506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1968506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1969506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1970506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19719c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1972506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1973506f1d07SSam Ravnborg defined by each seccomp mode. 1974506f1d07SSam Ravnborg 1975506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1976506f1d07SSam Ravnborg 1977506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1978506f1d07SSam Ravnborg 1979506f1d07SSam Ravnborgconfig KEXEC 1980506f1d07SSam Ravnborg bool "kexec system call" 19812965faa5SDave Young select KEXEC_CORE 19828f9ca475SIngo Molnar ---help--- 1983506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1984506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1985506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1986506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1987506f1d07SSam Ravnborg 1988506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1989506f1d07SSam Ravnborg 1990506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1991506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1992bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1993bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1994bf220695SGeert Uytterhoeven made. 1995506f1d07SSam Ravnborg 199674ca317cSVivek Goyalconfig KEXEC_FILE 199774ca317cSVivek Goyal bool "kexec file based system call" 19982965faa5SDave Young select KEXEC_CORE 199974ca317cSVivek Goyal select BUILD_BIN2C 200074ca317cSVivek Goyal depends on X86_64 200174ca317cSVivek Goyal depends on CRYPTO=y 200274ca317cSVivek Goyal depends on CRYPTO_SHA256=y 200374ca317cSVivek Goyal ---help--- 200474ca317cSVivek Goyal This is new version of kexec system call. This system call is 200574ca317cSVivek Goyal file based and takes file descriptors as system call argument 200674ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 200774ca317cSVivek Goyal accepted by previous system call. 200874ca317cSVivek Goyal 2009b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY 2010b799a09fSAKASHI Takahiro def_bool KEXEC_FILE 2011b799a09fSAKASHI Takahiro 20128e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 20138e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 201474ca317cSVivek Goyal depends on KEXEC_FILE 20158e7d8381SVivek Goyal ---help--- 20168e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 2017d8eb8940SBorislav Petkov the kexec_file_load() syscall. 20188e7d8381SVivek Goyal 2019d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 2020d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 2021d8eb8940SBorislav Petkov loaded in order for this to work. 20228e7d8381SVivek Goyal 20238e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 20248e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 20258e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 20268e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 20278e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 20288e7d8381SVivek Goyal ---help--- 20298e7d8381SVivek Goyal Enable bzImage signature verification support. 20308e7d8381SVivek Goyal 2031506f1d07SSam Ravnborgconfig CRASH_DUMP 203204b69447SPavel Machek bool "kernel crash dumps" 2033506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20348f9ca475SIngo Molnar ---help--- 2035506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2036506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2037506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2038506f1d07SSam Ravnborg a specially reserved region and then later executed after 2039506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2040506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2041506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2042506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2043506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2044506f1d07SSam Ravnborg 20453ab83521SHuang Yingconfig KEXEC_JUMP 20466ea30386SKees Cook bool "kexec jump" 2047fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20488f9ca475SIngo Molnar ---help--- 204989081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 205089081d17SHuang Ying code in physical address mode via KEXEC 20513ab83521SHuang Ying 2052506f1d07SSam Ravnborgconfig PHYSICAL_START 20536a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2054ceefccc9SH. Peter Anvin default "0x1000000" 20558f9ca475SIngo Molnar ---help--- 2056506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2057506f1d07SSam Ravnborg 2058506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2059506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2060506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2061506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2062506f1d07SSam Ravnborg address. 2063506f1d07SSam Ravnborg 2064506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2065506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2066506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2067506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2068506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2069506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2070506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2071506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2072506f1d07SSam Ravnborg 2073ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2074ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2075ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2076ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2077ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2078ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2079ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2080ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2081ceefccc9SH. Peter Anvin for more details about crash dumps. 2082506f1d07SSam Ravnborg 2083506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2084506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2085506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2086506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2087506f1d07SSam Ravnborg is present because there are users out there who continue to use 2088506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2089506f1d07SSam Ravnborg line. 2090506f1d07SSam Ravnborg 2091506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2092506f1d07SSam Ravnborg 2093506f1d07SSam Ravnborgconfig RELOCATABLE 209426717808SH. Peter Anvin bool "Build a relocatable kernel" 209526717808SH. Peter Anvin default y 20968f9ca475SIngo Molnar ---help--- 2097506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2098506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2099506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2100506f1d07SSam Ravnborg but are discarded at runtime. 2101506f1d07SSam Ravnborg 2102506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2103506f1d07SSam Ravnborg must live at a different physical address than the primary 2104506f1d07SSam Ravnborg kernel. 2105506f1d07SSam Ravnborg 2106506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2107506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 21088ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2109506f1d07SSam Ravnborg 21108ab3820fSKees Cookconfig RANDOMIZE_BASE 2111e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 21128ab3820fSKees Cook depends on RELOCATABLE 21136807c846SIngo Molnar default y 21148ab3820fSKees Cook ---help--- 2115e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2116e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2117e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2118e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2119e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2120e8581e3dSBaoquan He code internals. 2121e8581e3dSBaoquan He 2122ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2123ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2124ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2125ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2126ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2127ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2128ed9f007eSKees Cook 2129ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2130ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2131ed9f007eSKees Cook 512MB (8 bits of entropy). 21328ab3820fSKees Cook 2133a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2134e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2135e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2136ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2137ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2138ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2139ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2140ed9f007eSKees Cook theoretically possible, but the implementations are further 2141ed9f007eSKees Cook limited due to memory layouts. 2142e8581e3dSBaoquan He 21436807c846SIngo Molnar If unsure, say Y. 2144da2b6fb9SKees Cook 21458ab3820fSKees Cook# Relocation on x86 needs some additional build support 2146845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2147845adf72SH. Peter Anvin def_bool y 21488ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2149845adf72SH. Peter Anvin 2150506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2151a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21528ab3820fSKees Cook default "0x200000" 2153a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2154a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21558f9ca475SIngo Molnar ---help--- 2156506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2157506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2158506f1d07SSam Ravnborg address which meets above alignment restriction. 2159506f1d07SSam Ravnborg 2160506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2161506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2162506f1d07SSam Ravnborg address aligned to above value and run from there. 2163506f1d07SSam Ravnborg 2164506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2165506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2166506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2167506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2168506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2169506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2170506f1d07SSam Ravnborg above alignment restrictions. 2171506f1d07SSam Ravnborg 2172a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2173a0215061SKees Cook this value must be a multiple of 0x200000. 2174a0215061SKees Cook 2175506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2176506f1d07SSam Ravnborg 2177eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT 2178eedb92abSKirill A. Shutemov bool 2179eedb92abSKirill A. Shutemov ---help--- 2180eedb92abSKirill A. Shutemov This option makes base addresses of vmalloc and vmemmap as well as 2181eedb92abSKirill A. Shutemov __PAGE_OFFSET movable during boot. 2182eedb92abSKirill A. Shutemov 21830483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21840483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21850483e1faSThomas Garnier depends on X86_64 21860483e1faSThomas Garnier depends on RANDOMIZE_BASE 2187eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 21880483e1faSThomas Garnier default RANDOMIZE_BASE 21890483e1faSThomas Garnier ---help--- 21900483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21910483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21920483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21930483e1faSThomas Garnier 21940483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21950483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21960483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21970483e1faSThomas Garnier addresses for each memory section. 21980483e1faSThomas Garnier 21996807c846SIngo Molnar If unsure, say Y. 22000483e1faSThomas Garnier 220190397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 220290397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 220390397a41SThomas Garnier depends on RANDOMIZE_MEMORY 220490397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 220590397a41SThomas Garnier default "0x0" 220690397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 220790397a41SThomas Garnier range 0x0 0x40 220890397a41SThomas Garnier ---help--- 220990397a41SThomas Garnier Define the padding in terabytes added to the existing physical 221090397a41SThomas Garnier memory size during kernel memory randomization. It is useful 221190397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 221290397a41SThomas Garnier address randomization. 221390397a41SThomas Garnier 221490397a41SThomas Garnier If unsure, leave at the default value. 221590397a41SThomas Garnier 2216506f1d07SSam Ravnborgconfig HOTPLUG_CPU 22177c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 221840b31360SStephen Rothwell depends on SMP 2219506f1d07SSam Ravnborg ---help--- 22207c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 22217c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 22227c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 22237c13e6a3SDimitri Sivanich automatically on SMP systems. ) 22247c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2225506f1d07SSam Ravnborg 222680aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 222780aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 222880aa1dffSFenghua Yu default n 22292c922cd0SKees Cook depends on HOTPLUG_CPU 223080aa1dffSFenghua Yu ---help--- 223180aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 223280aa1dffSFenghua Yu 223380aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 223480aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 223580aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 223680aa1dffSFenghua Yu 223780aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 223880aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 223980aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 224080aa1dffSFenghua Yu 224180aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 224280aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 224380aa1dffSFenghua Yu 224480aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 224580aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 224680aa1dffSFenghua Yu be other CPU0 dependencies. 224780aa1dffSFenghua Yu 224880aa1dffSFenghua Yu Please make sure the dependencies are under your control before 224980aa1dffSFenghua Yu you enable this feature. 225080aa1dffSFenghua Yu 225180aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 225280aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 225380aa1dffSFenghua Yu parameter cpu0_hotplug. 225480aa1dffSFenghua Yu 2255a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2256a71c8bc5SFenghua Yu def_bool n 2257a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 22582c922cd0SKees Cook depends on HOTPLUG_CPU 2259a71c8bc5SFenghua Yu ---help--- 2260a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2261a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2262a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2263a71c8bc5SFenghua Yu 2264a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2265a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2266a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2267a71c8bc5SFenghua Yu 2268a71c8bc5SFenghua Yu If unsure, say N. 2269a71c8bc5SFenghua Yu 2270506f1d07SSam Ravnborgconfig COMPAT_VDSO 2271b0b49f26SAndy Lutomirski def_bool n 2272b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2273953fee1dSIngo Molnar depends on COMPAT_32 22748f9ca475SIngo Molnar ---help--- 2275b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2276b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2277b0b49f26SAndy Lutomirski indicated in its segment table. 2278e84446deSRandy Dunlap 2279b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2280b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2281b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2282b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2283b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2284506f1d07SSam Ravnborg 2285b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2286b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2287b0b49f26SAndy Lutomirski 2288b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2289b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2290b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2291b0b49f26SAndy Lutomirski 2292b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2293b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2294506f1d07SSam Ravnborg 22953dc33bd3SKees Cookchoice 22963dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22973dc33bd3SKees Cook depends on X86_64 22983dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 22993dc33bd3SKees Cook help 23003dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 23013dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 23023dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 23033dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 23043dc33bd3SKees Cook 23053dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 2306076ca272SAndy Lutomirski line parameter vsyscall=[emulate|none]. 23073dc33bd3SKees Cook 23083dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 23093dc33bd3SKees Cook static binaries, you can say None without a performance penalty 23103dc33bd3SKees Cook to improve security. 23113dc33bd3SKees Cook 23123dc33bd3SKees Cook If unsure, select "Emulate". 23133dc33bd3SKees Cook 23143dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 23153dc33bd3SKees Cook bool "Emulate" 23163dc33bd3SKees Cook help 23173dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 23183dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 23193dc33bd3SKees Cook non-executable, but it still contains known contents, 23203dc33bd3SKees Cook which could be used in certain rare security vulnerability 23213dc33bd3SKees Cook exploits. This configuration is recommended when userspace 23223dc33bd3SKees Cook still uses the vsyscall area. 23233dc33bd3SKees Cook 23243dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 23253dc33bd3SKees Cook bool "None" 23263dc33bd3SKees Cook help 23273dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 23283dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 23293dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 23303dc33bd3SKees Cook will be reported to dmesg, so that either old or 23313dc33bd3SKees Cook malicious userspace programs can be identified. 23323dc33bd3SKees Cook 23333dc33bd3SKees Cookendchoice 23343dc33bd3SKees Cook 2335516cbf37STim Birdconfig CMDLINE_BOOL 2336516cbf37STim Bird bool "Built-in kernel command line" 23378f9ca475SIngo Molnar ---help--- 2338516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2339516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2340516cbf37STim Bird necessary or convenient to provide some or all of the 2341516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2342516cbf37STim Bird to not rely on the boot loader to provide them.) 2343516cbf37STim Bird 2344516cbf37STim Bird To compile command line arguments into the kernel, 2345516cbf37STim Bird set this option to 'Y', then fill in the 234669711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2347516cbf37STim Bird 2348516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2349516cbf37STim Bird should leave this option set to 'N'. 2350516cbf37STim Bird 2351516cbf37STim Birdconfig CMDLINE 2352516cbf37STim Bird string "Built-in kernel command string" 2353516cbf37STim Bird depends on CMDLINE_BOOL 2354516cbf37STim Bird default "" 23558f9ca475SIngo Molnar ---help--- 2356516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2357516cbf37STim Bird image and used at boot time. If the boot loader provides a 2358516cbf37STim Bird command line at boot time, it is appended to this string to 2359516cbf37STim Bird form the full kernel command line, when the system boots. 2360516cbf37STim Bird 2361516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2362516cbf37STim Bird change this behavior. 2363516cbf37STim Bird 2364516cbf37STim Bird In most cases, the command line (whether built-in or provided 2365516cbf37STim Bird by the boot loader) should specify the device for the root 2366516cbf37STim Bird file system. 2367516cbf37STim Bird 2368516cbf37STim Birdconfig CMDLINE_OVERRIDE 2369516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2370516cbf37STim Bird depends on CMDLINE_BOOL 23718f9ca475SIngo Molnar ---help--- 2372516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2373516cbf37STim Bird command line, and use ONLY the built-in command line. 2374516cbf37STim Bird 2375516cbf37STim Bird This is used to work around broken boot loaders. This should 2376516cbf37STim Bird be set to 'N' under normal conditions. 2377516cbf37STim Bird 2378a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2379a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2380a5b9e5a2SAndy Lutomirski default y 2381a5b9e5a2SAndy Lutomirski ---help--- 2382a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2383a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2384a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2385a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2386a5b9e5a2SAndy Lutomirski threading libraries. 2387a5b9e5a2SAndy Lutomirski 2388a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2389a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2390a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2391a5b9e5a2SAndy Lutomirski 2392a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2393a5b9e5a2SAndy Lutomirski 2394b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2395b700e7f0SSeth Jennings 2396506f1d07SSam Ravnborgendmenu 2397506f1d07SSam Ravnborg 23983072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 23993072e413SMichal Hocko def_bool y 24003072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 24013072e413SMichal Hocko 2402506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2403506f1d07SSam Ravnborg def_bool y 2404506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2405506f1d07SSam Ravnborg 240635551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 240735551053SGary Hade def_bool y 240835551053SGary Hade depends on MEMORY_HOTPLUG 240935551053SGary Hade 2410e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2411645a7919STejun Heo def_bool y 2412e534c7c5SLee Schermerhorn depends on NUMA 2413e534c7c5SLee Schermerhorn 24149491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 24159491846fSKirill A. Shutemov def_bool y 24169491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 24179491846fSKirill A. Shutemov 2418c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2419c177c81eSNaoya Horiguchi def_bool y 2420c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2421c177c81eSNaoya Horiguchi 24229c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 24239c670ea3SNaoya Horiguchi def_bool y 24249c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 24259c670ea3SNaoya Horiguchi 2426da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2427e279b6c1SSam Ravnborg 2428e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 24293c2362e6SHarvey Harrison def_bool y 2430e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2431e279b6c1SSam Ravnborg 2432e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2433e279b6c1SSam Ravnborg 2434e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2435e279b6c1SSam Ravnborg 2436efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2437efafc8b2SFeng Tang 2438a6b68076SAndi Kleenconfig X86_APM_BOOT 24396fc108a0SJan Beulich def_bool y 2440282e5aabSPaul Bolle depends on APM 2441a6b68076SAndi Kleen 2442e279b6c1SSam Ravnborgmenuconfig APM 2443e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2444efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2445e279b6c1SSam Ravnborg ---help--- 2446e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2447e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2448e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2449e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2450e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2451e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2452e279b6c1SSam Ravnborg 2453e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2454e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2455e279b6c1SSam Ravnborg 2456e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2457e279b6c1SSam Ravnborg machines with more than one CPU. 2458e279b6c1SSam Ravnborg 2459e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 24602dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 24612dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2462e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2463e279b6c1SSam Ravnborg 2464e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2465e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2466e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2467e279b6c1SSam Ravnborg 2468e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2469e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2470e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2471e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2472e279b6c1SSam Ravnborg 2473e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2474e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2475e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2476e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2477e279b6c1SSam Ravnborg APM in your BIOS). 2478e279b6c1SSam Ravnborg 2479e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2480e279b6c1SSam Ravnborg "weird" problems: 2481e279b6c1SSam Ravnborg 2482e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2483e279b6c1SSam Ravnborg enabled. 2484e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2485e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2486e279b6c1SSam Ravnborg the "no387" option to the kernel 2487e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2488e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2489e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2490e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2491e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2492e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2493e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2494e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2495e279b6c1SSam Ravnborg 11) exchange RAM chips 2496e279b6c1SSam Ravnborg 12) exchange the motherboard. 2497e279b6c1SSam Ravnborg 2498e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2499e279b6c1SSam Ravnborg module will be called apm. 2500e279b6c1SSam Ravnborg 2501e279b6c1SSam Ravnborgif APM 2502e279b6c1SSam Ravnborg 2503e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2504e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 25058f9ca475SIngo Molnar ---help--- 2506e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2507e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2508e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2509e279b6c1SSam Ravnborg 2510e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2511e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2512e279b6c1SSam Ravnborg ---help--- 2513e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2514e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2515e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2516e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2517e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2518e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2519e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2520e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2521e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2522e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2523e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2524e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2525e279b6c1SSam Ravnborg this feature. 2526e279b6c1SSam Ravnborg 2527e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2528dd8af076SLen Brown depends on CPU_IDLE 2529e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 25308f9ca475SIngo Molnar ---help--- 2531e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2532e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2533e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2534e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2535e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2536e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2537e279b6c1SSam Ravnborg this option does nothing.) 2538e279b6c1SSam Ravnborg 2539e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2540e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 25418f9ca475SIngo Molnar ---help--- 2542e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2543e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2544e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2545e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2546e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2547e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2548e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2549e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2550e279b6c1SSam Ravnborg especially if you are using gpm. 2551e279b6c1SSam Ravnborg 2552e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2553e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 25548f9ca475SIngo Molnar ---help--- 2555e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2556e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2557e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2558e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2559e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2560e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2561e279b6c1SSam Ravnborg 2562e279b6c1SSam Ravnborgendif # APM 2563e279b6c1SSam Ravnborg 2564bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2565e279b6c1SSam Ravnborg 2566e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2567e279b6c1SSam Ravnborg 256827471fdbSAndy Henroidsource "drivers/idle/Kconfig" 256927471fdbSAndy Henroid 2570e279b6c1SSam Ravnborgendmenu 2571e279b6c1SSam Ravnborg 2572e279b6c1SSam Ravnborg 2573e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2574e279b6c1SSam Ravnborg 2575e279b6c1SSam Ravnborgconfig PCI 25761ac97018SIngo Molnar bool "PCI support" 25771c858087SAdrian Bunk default y 25788f9ca475SIngo Molnar ---help--- 2579e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2580e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2581e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2582e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2583e279b6c1SSam Ravnborg 2584e279b6c1SSam Ravnborgchoice 2585e279b6c1SSam Ravnborg prompt "PCI access mode" 2586efefa6f6SIngo Molnar depends on X86_32 && PCI 2587e279b6c1SSam Ravnborg default PCI_GOANY 2588e279b6c1SSam Ravnborg ---help--- 2589e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2590e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2591e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2592e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2593e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2594e279b6c1SSam Ravnborg 2595e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2596e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2597e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2598e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2599e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2600e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2601e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2602e279b6c1SSam Ravnborg 2603e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2604e279b6c1SSam Ravnborg bool "BIOS" 2605e279b6c1SSam Ravnborg 2606e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2607e279b6c1SSam Ravnborg bool "MMConfig" 2608e279b6c1SSam Ravnborg 2609e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2610e279b6c1SSam Ravnborg bool "Direct" 2611e279b6c1SSam Ravnborg 26123ef0e1f8SAndres Salomonconfig PCI_GOOLPC 261376fb6570SDaniel Drake bool "OLPC XO-1" 26143ef0e1f8SAndres Salomon depends on OLPC 26153ef0e1f8SAndres Salomon 26162bdd1b03SAndres Salomonconfig PCI_GOANY 26172bdd1b03SAndres Salomon bool "Any" 26182bdd1b03SAndres Salomon 2619e279b6c1SSam Ravnborgendchoice 2620e279b6c1SSam Ravnborg 2621e279b6c1SSam Ravnborgconfig PCI_BIOS 26223c2362e6SHarvey Harrison def_bool y 2623efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2624e279b6c1SSam Ravnborg 2625e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2626e279b6c1SSam Ravnborgconfig PCI_DIRECT 26273c2362e6SHarvey Harrison def_bool y 26280aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2629e279b6c1SSam Ravnborg 2630e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2631b45c9f36SJan Kiszka bool "Support mmconfig PCI config space access" if X86_64 2632b45c9f36SJan Kiszka default y 26338364e1f8SJan Kiszka depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST) 2634b45c9f36SJan Kiszka depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) 2635e279b6c1SSam Ravnborg 26363ef0e1f8SAndres Salomonconfig PCI_OLPC 26372bdd1b03SAndres Salomon def_bool y 26382bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 26393ef0e1f8SAndres Salomon 2640b5401a96SAlex Nixonconfig PCI_XEN 2641b5401a96SAlex Nixon def_bool y 2642b5401a96SAlex Nixon depends on PCI && XEN 2643b5401a96SAlex Nixon select SWIOTLB_XEN 2644b5401a96SAlex Nixon 2645e279b6c1SSam Ravnborgconfig PCI_DOMAINS 26463c2362e6SHarvey Harrison def_bool y 2647e279b6c1SSam Ravnborg depends on PCI 2648e279b6c1SSam Ravnborg 26498364e1f8SJan Kiszkaconfig MMCONF_FAM10H 26508364e1f8SJan Kiszka def_bool y 26518364e1f8SJan Kiszka depends on X86_64 && PCI_MMCONFIG && ACPI 2652e279b6c1SSam Ravnborg 26533f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 26546a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 26556ea30386SKees Cook depends on PCI 26563f6ea84aSIra W. Snyder help 26573f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 26583f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 26593f6ea84aSIra W. Snyder not have ACPI. 26603f6ea84aSIra W. Snyder 266164a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 266264a5fed6SBjorn Helgaas is known to be incomplete. 266364a5fed6SBjorn Helgaas 266464a5fed6SBjorn Helgaas You should say N unless you know you need this. 266564a5fed6SBjorn Helgaas 2666e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2667e279b6c1SSam Ravnborg 26683a495511SWilliam Breathitt Grayconfig ISA_BUS 266917a2a129SWilliam Breathitt Gray bool "ISA bus support on modern systems" if EXPERT 26703a495511SWilliam Breathitt Gray help 267117a2a129SWilliam Breathitt Gray Expose ISA bus device drivers and options available for selection and 267217a2a129SWilliam Breathitt Gray configuration. Enable this option if your target machine has an ISA 267317a2a129SWilliam Breathitt Gray bus. ISA is an older system, displaced by PCI and newer bus 267417a2a129SWilliam Breathitt Gray architectures -- if your target machine is modern, it probably does 267517a2a129SWilliam Breathitt Gray not have an ISA bus. 26763a495511SWilliam Breathitt Gray 26773a495511SWilliam Breathitt Gray If unsure, say N. 26783a495511SWilliam Breathitt Gray 26791c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2680e279b6c1SSam Ravnborgconfig ISA_DMA_API 26811c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26821c00f016SDavid Rientjes default y 26831c00f016SDavid Rientjes help 26841c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26851c00f016SDavid Rientjes If unsure, say Y. 2686e279b6c1SSam Ravnborg 268751e68d05SLinus Torvaldsif X86_32 268851e68d05SLinus Torvalds 2689e279b6c1SSam Ravnborgconfig ISA 2690e279b6c1SSam Ravnborg bool "ISA support" 26918f9ca475SIngo Molnar ---help--- 2692e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2693e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2694e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2695e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2696e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2697e279b6c1SSam Ravnborg 2698e279b6c1SSam Ravnborgconfig EISA 2699e279b6c1SSam Ravnborg bool "EISA support" 2700e279b6c1SSam Ravnborg depends on ISA 2701e279b6c1SSam Ravnborg ---help--- 2702e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2703e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2704e279b6c1SSam Ravnborg 2705e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2706e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2707e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2708e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2709e279b6c1SSam Ravnborg 2710e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2711e279b6c1SSam Ravnborg 2712e279b6c1SSam Ravnborg Otherwise, say N. 2713e279b6c1SSam Ravnborg 2714e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2715e279b6c1SSam Ravnborg 2716e279b6c1SSam Ravnborgconfig SCx200 2717e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 27188f9ca475SIngo Molnar ---help--- 2719e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2720e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2721e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2722e279b6c1SSam Ravnborg for other scx200_* drivers. 2723e279b6c1SSam Ravnborg 2724e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2725e279b6c1SSam Ravnborg 2726e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2727e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2728592913ecSJohn Stultz depends on SCx200 2729e279b6c1SSam Ravnborg default y 27308f9ca475SIngo Molnar ---help--- 2731e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2732e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2733e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2734e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2735e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2736e279b6c1SSam Ravnborg 27373ef0e1f8SAndres Salomonconfig OLPC 27383ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 273954008979SThomas Gleixner depends on !X86_PAE 27403c554946SAndres Salomon select GPIOLIB 2741dc3119e7SThomas Gleixner select OF 274245bb1674SDaniel Drake select OF_PROMTREE 2743b4e51854SGrant Likely select IRQ_DOMAIN 27448f9ca475SIngo Molnar ---help--- 27453ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 27463ef0e1f8SAndres Salomon XO hardware. 27473ef0e1f8SAndres Salomon 2748a3128588SDaniel Drakeconfig OLPC_XO1_PM 2749a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 275097c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2751a3128588SDaniel Drake select MFD_CORE 2752bf1ebf00SDaniel Drake ---help--- 275397c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2754bf1ebf00SDaniel Drake 2755cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2756cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2757cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2758cfee9597SDaniel Drake ---help--- 2759cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2760cfee9597SDaniel Drake programmable wakeup source. 2761cfee9597SDaniel Drake 27627feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27637feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 276492e830f2SArnd Bergmann depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2765ed8e47feSRandy Dunlap depends on INPUT=y 2766d8d01a63SDaniel Drake select POWER_SUPPLY 27677feda8e9SDaniel Drake ---help--- 27687feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27697bc74b3dSDaniel Drake - EC-driven system wakeups 27707feda8e9SDaniel Drake - Power button 27717bc74b3dSDaniel Drake - Ebook switch 27722cf2baeaSDaniel Drake - Lid switch 2773e1040ac6SDaniel Drake - AC adapter status updates 2774e1040ac6SDaniel Drake - Battery status updates 27757feda8e9SDaniel Drake 2776a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2777a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2778d8d01a63SDaniel Drake depends on OLPC && ACPI 2779d8d01a63SDaniel Drake select POWER_SUPPLY 2780a0f30f59SDaniel Drake ---help--- 2781a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2782a0f30f59SDaniel Drake - EC-driven system wakeups 2783a0f30f59SDaniel Drake - AC adapter status updates 2784a0f30f59SDaniel Drake - Battery status updates 2785e279b6c1SSam Ravnborg 2786d4f3e350SEd Wildgooseconfig ALIX 2787d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2788d4f3e350SEd Wildgoose select GPIOLIB 2789d4f3e350SEd Wildgoose ---help--- 2790d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2791d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2792d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2793d4f3e350SEd Wildgoose get added here. 2794d4f3e350SEd Wildgoose 2795d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2796d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2797d4f3e350SEd Wildgoose 2798d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2799d4f3e350SEd Wildgoose 2800da4e3302SPhilip Prindevilleconfig NET5501 2801da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2802da4e3302SPhilip Prindeville select GPIOLIB 2803da4e3302SPhilip Prindeville ---help--- 2804da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2805da4e3302SPhilip Prindeville 28063197059aSPhilip A. Prindevilleconfig GEOS 28073197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 28083197059aSPhilip A. Prindeville select GPIOLIB 28093197059aSPhilip A. Prindeville depends on DMI 28103197059aSPhilip A. Prindeville ---help--- 28113197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 28123197059aSPhilip A. Prindeville 28137d029125SVivien Didelotconfig TS5500 28147d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 28157d029125SVivien Didelot depends on MELAN 28167d029125SVivien Didelot select CHECK_SIGNATURE 28177d029125SVivien Didelot select NEW_LEDS 28187d029125SVivien Didelot select LEDS_CLASS 28197d029125SVivien Didelot ---help--- 28207d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 28217d029125SVivien Didelot 2822e279b6c1SSam Ravnborgendif # X86_32 2823e279b6c1SSam Ravnborg 282423ac4ae8SAndreas Herrmannconfig AMD_NB 2825e279b6c1SSam Ravnborg def_bool y 28260e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2827e279b6c1SSam Ravnborg 2828e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2829e279b6c1SSam Ravnborg 2830388b78adSAlexandre Bounineconfig RAPIDIO 2831fdf90abcSAlexandre Bounine tristate "RapidIO support" 2832388b78adSAlexandre Bounine depends on PCI 2833388b78adSAlexandre Bounine default n 2834388b78adSAlexandre Bounine help 2835fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2836388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2837388b78adSAlexandre Bounine 2838388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2839388b78adSAlexandre Bounine 2840e3263ab3SDavid Herrmannconfig X86_SYSFB 2841e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2842e3263ab3SDavid Herrmann help 2843e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2844e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2845e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2846e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2847e3263ab3SDavid Herrmann to x86. 2848e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2849e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2850e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2851e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2852e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2853e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2854e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2855e3263ab3SDavid Herrmann 2856e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2857e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2858e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2859e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2860e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2861e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2862e3263ab3SDavid Herrmann incompatible with simplefb. 2863e3263ab3SDavid Herrmann 2864e3263ab3SDavid Herrmann If unsure, say Y. 2865e3263ab3SDavid Herrmann 2866e279b6c1SSam Ravnborgendmenu 2867e279b6c1SSam Ravnborg 2868e279b6c1SSam Ravnborg 2869e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2870e279b6c1SSam Ravnborg 2871e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2872e279b6c1SSam Ravnborg 2873e279b6c1SSam Ravnborgconfig IA32_EMULATION 2874e279b6c1SSam Ravnborg bool "IA32 Emulation" 2875e279b6c1SSam Ravnborg depends on X86_64 287639f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2877d1603990SRandy Dunlap select BINFMT_ELF 2878a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 287939f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28808f9ca475SIngo Molnar ---help--- 28815fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28825fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28835fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2884e279b6c1SSam Ravnborg 2885e279b6c1SSam Ravnborgconfig IA32_AOUT 2886e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28876b213e1bSDavid Woodhouse depends on IA32_EMULATION 28888f9ca475SIngo Molnar ---help--- 2889e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2890e279b6c1SSam Ravnborg 28910bf62763SH. Peter Anvinconfig X86_X32 28926ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28939b54050bSBrian Gerst depends on X86_64 28945fd92e65SH. J. Lu ---help--- 28955fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28965fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28975fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28985fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28995fd92e65SH. J. Lu 29005fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 29015fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 29025fd92e65SH. J. Lu option set. 29035fd92e65SH. J. Lu 2904953fee1dSIngo Molnarconfig COMPAT_32 2905953fee1dSIngo Molnar def_bool y 2906953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2907953fee1dSIngo Molnar select HAVE_UID16 2908953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2909953fee1dSIngo Molnar 2910e279b6c1SSam Ravnborgconfig COMPAT 29113c2362e6SHarvey Harrison def_bool y 29120bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2913e279b6c1SSam Ravnborg 29143120e25eSJan Beulichif COMPAT 2915e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 29163120e25eSJan Beulich def_bool y 2917e279b6c1SSam Ravnborg 2918e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 29193c2362e6SHarvey Harrison def_bool y 29203120e25eSJan Beulich depends on SYSVIPC 29213120e25eSJan Beulichendif 2922ee009e4aSDavid Howells 2923e279b6c1SSam Ravnborgendmenu 2924e279b6c1SSam Ravnborg 2925e279b6c1SSam Ravnborg 2926e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2927e5beae16SKeith Packard def_bool y 2928e5beae16SKeith Packard depends on X86_32 2929e5beae16SKeith Packard 29304692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 29314692d77fSAlessandro Rubini bool 293283125a3aSAlessandro Rubini depends on X86_64 || STA2X11 29334692d77fSAlessandro Rubini 2934f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2935f7219a53SAlessandro Rubini bool 293683125a3aSAlessandro Rubini depends on STA2X11 2937f7219a53SAlessandro Rubini 2938e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2939e585513bSKirill A. Shutemov def_bool y 2940e585513bSKirill A. Shutemov 2941e279b6c1SSam Ravnborgsource "net/Kconfig" 2942e279b6c1SSam Ravnborg 2943e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2944e279b6c1SSam Ravnborg 2945e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2946e279b6c1SSam Ravnborg 2947e279b6c1SSam Ravnborgsource "fs/Kconfig" 2948e279b6c1SSam Ravnborg 2949e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2950e279b6c1SSam Ravnborg 2951e279b6c1SSam Ravnborgsource "security/Kconfig" 2952e279b6c1SSam Ravnborg 2953e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2954e279b6c1SSam Ravnborg 2955edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2956edf88417SAvi Kivity 2957e279b6c1SSam Ravnborgsource "lib/Kconfig" 2958