1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 2daa93fabSSam Ravnborg# Select 32 or 64 bit 3daa93fabSSam Ravnborgconfig 64BIT 4*104daea1SMasahiro Yamada bool "64-bit kernel" if "$(ARCH)" = "x86" 5*104daea1SMasahiro Yamada default "$(ARCH)" != "i386" 68f9ca475SIngo Molnar ---help--- 7daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 8daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 9daa93fabSSam Ravnborg 10daa93fabSSam Ravnborgconfig X86_32 113120e25eSJan Beulich def_bool y 123120e25eSJan Beulich depends on !64BIT 13341c787eSIngo Molnar # Options that are inherently 32-bit kernel only: 14341c787eSIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION 15341c787eSIngo Molnar select CLKSRC_I8253 16341c787eSIngo Molnar select CLONE_BACKWARDS 17341c787eSIngo Molnar select HAVE_AOUT 18341c787eSIngo Molnar select HAVE_GENERIC_DMA_COHERENT 19341c787eSIngo Molnar select MODULES_USE_ELF_REL 20341c787eSIngo Molnar select OLD_SIGACTION 21daa93fabSSam Ravnborg 22daa93fabSSam Ravnborgconfig X86_64 233120e25eSJan Beulich def_bool y 243120e25eSJan Beulich depends on 64BIT 25d94e0685SIngo Molnar # Options that are inherently 64-bit kernel only: 26e1073d1eSAneesh Kumar K.V select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA 27d94e0685SIngo Molnar select ARCH_SUPPORTS_INT128 28d94e0685SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF 29d94e0685SIngo Molnar select HAVE_ARCH_SOFT_DIRTY 30d94e0685SIngo Molnar select MODULES_USE_ELF_RELA 31d94e0685SIngo Molnar select X86_DEV_DMA_OPS 32f8781c4aSDominik Brodowski select ARCH_HAS_SYSCALL_WRAPPER 331032c0baSSam Ravnborg 34d94e0685SIngo Molnar# 35d94e0685SIngo Molnar# Arch settings 36d94e0685SIngo Molnar# 37d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 38d94e0685SIngo Molnar# ported to 32-bit as well. ) 39d94e0685SIngo Molnar# 408d5fffb9SSam Ravnborgconfig X86 413c2362e6SHarvey Harrison def_bool y 42c763ea26SIngo Molnar # 43c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 44c763ea26SIngo Molnar # 456471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 466e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 476471b825SIngo Molnar select ANON_INODES 486471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 496471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 5091dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 51fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5221266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 536471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5472d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 55316d097cSDave Hansen select ARCH_HAS_FILTER_PGPROT 566974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 57957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 585c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 5910bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 60c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 6139208aa7SKees Cook select ARCH_HAS_REFCOUNT 620aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 63d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 646471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 65ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 66ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 67ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 68c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 6965f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 706471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 716471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 7277fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 735e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 746471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 756471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 766471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 776471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 786471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 79ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 80c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 8138d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 826471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 836471b825SIngo Molnar select CLKEVT_I8253 846471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 856471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 866471b825SIngo Molnar select DCACHE_WORD_ACCESS 87fec777c3SChristoph Hellwig select DMA_DIRECT_OPS 8845471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 8945471cd9SLinus Torvalds select EDAC_SUPPORT 906471b825SIngo Molnar select GENERIC_CLOCKEVENTS 916471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 926471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 936471b825SIngo Molnar select GENERIC_CMOS_UPDATE 946471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 9561dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 966471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 976471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 986471b825SIngo Molnar select GENERIC_IOMAP 99c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 1000fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 101ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1026471b825SIngo Molnar select GENERIC_IRQ_PROBE 103c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1046471b825SIngo Molnar select GENERIC_IRQ_SHOW 1056471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1066471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1076471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1086471b825SIngo Molnar select GENERIC_STRNLEN_USER 1096471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1107edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1116471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1126471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1136471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1146471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1156471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1166471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 117d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1186471b825SIngo Molnar select HAVE_ARCH_KGDB 1199e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1209e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1211b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1226471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 123f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 1246471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1256471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 126a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 127e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 128c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1296471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1306471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1316471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1326471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 133c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1346471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1356471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1366471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1376471b825SIngo Molnar select HAVE_DMA_API_DEBUG 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 187df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1886471b825SIngo Molnar select PERF_EVENTS 1893195ef59SPrarit Bhargava select RTC_LIB 190d6faca40SArnd Bergmann select RTC_MC146818_LIB 1916471b825SIngo Molnar select SPARSE_IRQ 19283fe27eaSPranith Kumar select SRCU 1936471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 19415f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1956471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1966471b825SIngo Molnar select VIRT_TO_BUS 1976471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1987d8330a5SBalbir Singh 199ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 2003120e25eSJan Beulich def_bool y 2013120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 202ba7e4d13SIngo Molnar 20351b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 20451b26adaSLinus Torvalds string 20551b26adaSLinus Torvalds default "elf32-i386" if X86_32 20651b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 20751b26adaSLinus Torvalds 20873531905SSam Ravnborgconfig ARCH_DEFCONFIG 209b9b39bfbSSam Ravnborg string 21073531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 21173531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 212b9b39bfbSSam Ravnborg 2138d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2143c2362e6SHarvey Harrison def_bool y 2158d5fffb9SSam Ravnborg 2168d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2173c2362e6SHarvey Harrison def_bool y 2188d5fffb9SSam Ravnborg 2198d5fffb9SSam Ravnborgconfig MMU 2203c2362e6SHarvey Harrison def_bool y 2218d5fffb9SSam Ravnborg 2229e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2239e08f57dSDaniel Cashman default 28 if 64BIT 2249e08f57dSDaniel Cashman default 8 2259e08f57dSDaniel Cashman 2269e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2279e08f57dSDaniel Cashman default 32 if 64BIT 2289e08f57dSDaniel Cashman default 16 2299e08f57dSDaniel Cashman 2309e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2319e08f57dSDaniel Cashman default 8 2329e08f57dSDaniel Cashman 2339e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2349e08f57dSDaniel Cashman default 16 2359e08f57dSDaniel Cashman 2368d5fffb9SSam Ravnborgconfig SBUS 2378d5fffb9SSam Ravnborg bool 2388d5fffb9SSam Ravnborg 2393bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2403120e25eSJan Beulich def_bool y 241a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2423bc4e459SFUJITA Tomonori 24318e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2444a14d84eSAndrew Morton def_bool y 24518e98307SFUJITA Tomonori 2468d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2473120e25eSJan Beulich def_bool y 2483120e25eSJan Beulich depends on ISA_DMA_API 2498d5fffb9SSam Ravnborg 2508d5fffb9SSam Ravnborgconfig GENERIC_BUG 2513c2362e6SHarvey Harrison def_bool y 2528d5fffb9SSam Ravnborg depends on BUG 253b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 254b93a531eSJan Beulich 255b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 256b93a531eSJan Beulich bool 2578d5fffb9SSam Ravnborg 2588d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2593c2362e6SHarvey Harrison def_bool y 2608d5fffb9SSam Ravnborg 2618d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2623120e25eSJan Beulich def_bool y 2633120e25eSJan Beulich depends on ISA_DMA_API 2648d5fffb9SSam Ravnborg 2651032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2663120e25eSJan Beulich def_bool y 2671032c0baSSam Ravnborg 2681032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2691032c0baSSam Ravnborg def_bool y 2701032c0baSSam Ravnborg 2719a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2729a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2738d5fffb9SSam Ravnborg 2741b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2751b27d05bSPekka Enberg def_bool y 2761b27d05bSPekka Enberg 277316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT 278316d097cSDave Hansen def_bool y 279316d097cSDave Hansen 280dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 28189c9c4c5SBrian Gerst def_bool y 282b32ef636Stravis@sgi.com 28308fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 28408fc4580STejun Heo def_bool y 28508fc4580STejun Heo 28608fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 28711124411STejun Heo def_bool y 28811124411STejun Heo 289801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 290801e4062SJohannes Berg def_bool y 291801e4062SJohannes Berg 292f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 293f4cb5700SJohannes Berg def_bool y 294f4cb5700SJohannes Berg 295cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 296cfe28c5dSSteve Capper def_bool y 297cfe28c5dSSteve Capper 29853313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 29953313b2cSSteve Capper def_bool y 30053313b2cSSteve Capper 3018d5fffb9SSam Ravnborgconfig ZONE_DMA32 302e0fd24a3SJan Beulich def_bool y if X86_64 3038d5fffb9SSam Ravnborg 3048d5fffb9SSam Ravnborgconfig AUDIT_ARCH 305e0fd24a3SJan Beulich def_bool y if X86_64 3068d5fffb9SSam Ravnborg 307765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 308765c68bdSIngo Molnar def_bool y 309765c68bdSIngo Molnar 3106a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3116a11f75bSAkinobu Mita def_bool y 3126a11f75bSAkinobu Mita 313d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 314d6f2d75aSAndrey Ryabinin hex 315d6f2d75aSAndrey Ryabinin depends on KASAN 316d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 317d6f2d75aSAndrey Ryabinin 31869575d38SShane Wangconfig HAVE_INTEL_TXT 31969575d38SShane Wang def_bool y 3206ea30386SKees Cook depends on INTEL_IOMMU && ACPI 32169575d38SShane Wang 3226b0c3d44SSam Ravnborgconfig X86_32_SMP 3236b0c3d44SSam Ravnborg def_bool y 3246b0c3d44SSam Ravnborg depends on X86_32 && SMP 3256b0c3d44SSam Ravnborg 3266b0c3d44SSam Ravnborgconfig X86_64_SMP 3276b0c3d44SSam Ravnborg def_bool y 3286b0c3d44SSam Ravnborg depends on X86_64 && SMP 3296b0c3d44SSam Ravnborg 330ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 331ccbeed3aSTejun Heo def_bool y 3322bc2f688SKees Cook depends on X86_32 && CC_STACKPROTECTOR_NONE 333ccbeed3aSTejun Heo 3342b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3352b144498SSrikar Dronamraju def_bool y 3362b144498SSrikar Dronamraju 337d20642f0SRob Herringconfig FIX_EARLYCON_MEM 338d20642f0SRob Herring def_bool y 339d20642f0SRob Herring 34098233368SKirill A. Shutemovconfig PGTABLE_LEVELS 34198233368SKirill A. Shutemov int 34277ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 34398233368SKirill A. Shutemov default 4 if X86_64 34498233368SKirill A. Shutemov default 3 if X86_PAE 34598233368SKirill A. Shutemov default 2 34698233368SKirill A. Shutemov 347506f1d07SSam Ravnborgsource "init/Kconfig" 348dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3498d5fffb9SSam Ravnborg 350506f1d07SSam Ravnborgmenu "Processor type and features" 351506f1d07SSam Ravnborg 3525ee71535SRandy Dunlapconfig ZONE_DMA 3535ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3545ee71535SRandy Dunlap default y 3555ee71535SRandy Dunlap help 3565ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3575ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3585ee71535SRandy Dunlap Disable if no such devices will be used. 3595ee71535SRandy Dunlap 3605ee71535SRandy Dunlap If unsure, say Y. 3615ee71535SRandy Dunlap 362506f1d07SSam Ravnborgconfig SMP 363506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 364506f1d07SSam Ravnborg ---help--- 365506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3664a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3674a474157SRobert Graffham than one CPU, say Y. 368506f1d07SSam Ravnborg 3694a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 370506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 371506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3724a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 373506f1d07SSam Ravnborg will run faster if you say N here. 374506f1d07SSam Ravnborg 375506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 376506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 377506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 378506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 379506f1d07SSam Ravnborg 380506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 381506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 382506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 383506f1d07SSam Ravnborg 384395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 385c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 386506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 387506f1d07SSam Ravnborg 388506f1d07SSam Ravnborg If you don't know what to do here, say N. 389506f1d07SSam Ravnborg 3909def39beSJosh Triplettconfig X86_FEATURE_NAMES 3919def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3929def39beSJosh Triplett default y 3939def39beSJosh Triplett ---help--- 3949def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3959def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3969def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3979def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3989def39beSJosh Triplett 3999def39beSJosh Triplett If in doubt, say Y. 4009def39beSJosh Triplett 40106cd9a7dSYinghai Luconfig X86_X2APIC 40206cd9a7dSYinghai Lu bool "Support x2apic" 40319e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 40406cd9a7dSYinghai Lu ---help--- 40506cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40606cd9a7dSYinghai Lu 40706cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 40806cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 40906cd9a7dSYinghai Lu 41006cd9a7dSYinghai Lu If you don't know what to do here, say N. 41106cd9a7dSYinghai Lu 4126695c85bSYinghai Luconfig X86_MPPARSE 4136e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4147a527688SJan Beulich default y 4155ab74722SIngo Molnar depends on X86_LOCAL_APIC 4168f9ca475SIngo Molnar ---help--- 4176695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4186695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4196695c85bSYinghai Lu 420ddd70cf9SJun Nakajimaconfig GOLDFISH 421ddd70cf9SJun Nakajima def_bool y 422ddd70cf9SJun Nakajima depends on X86_GOLDFISH 423ddd70cf9SJun Nakajima 42476b04384SDavid Woodhouseconfig RETPOLINE 42576b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 42676b04384SDavid Woodhouse default y 427d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 42876b04384SDavid Woodhouse help 42976b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 43076b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 43176b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 43276b04384SDavid Woodhouse support for full protection. The kernel may run slower. 43376b04384SDavid Woodhouse 43476b04384SDavid Woodhouse Without compiler support, at least indirect branches in assembler 43576b04384SDavid Woodhouse code are eliminated. Since this includes the syscall entry path, 43676b04384SDavid Woodhouse it is not entirely pointless. 43776b04384SDavid Woodhouse 438f01d7d51SVikas Shivappaconfig INTEL_RDT 439f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 44078e99b4aSFenghua Yu default n 44178e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 44259fe5a77SThomas Gleixner select KERNFS 44378e99b4aSFenghua Yu help 444f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 445f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 446f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 447f01d7d51SVikas Shivappa Architecture Software Developer Manual. 44878e99b4aSFenghua Yu 44978e99b4aSFenghua Yu Say N if unsure. 45078e99b4aSFenghua Yu 4518425091fSRavikiran G Thirumalaiif X86_32 452a0d0bb4dSRandy Dunlapconfig X86_BIGSMP 453a0d0bb4dSRandy Dunlap bool "Support for big SMP systems with more than 8 CPUs" 454a0d0bb4dSRandy Dunlap depends on SMP 455a0d0bb4dSRandy Dunlap ---help--- 456a0d0bb4dSRandy Dunlap This option is needed for the systems that have more than 8 CPUs 457a0d0bb4dSRandy Dunlap 458c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 459c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 460c5c606d9SRavikiran G Thirumalai default y 4618f9ca475SIngo Molnar ---help--- 46206ac8346SIngo Molnar If you disable this option then the kernel will only support 46306ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 46406ac8346SIngo Molnar systems out there.) 46506ac8346SIngo Molnar 4668425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4678425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 468cb7b8023SBen Hutchings Goldfish (Android emulator) 4698425091fSRavikiran G Thirumalai AMD Elan 4708425091fSRavikiran G Thirumalai RDC R-321x SoC 4718425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 47283125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4733f4110a4SThomas Gleixner Moorestown MID devices 47406ac8346SIngo Molnar 47506ac8346SIngo Molnar If you have one of these systems, or if you want to build a 47606ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4778425091fSRavikiran G Thirumalaiendif 47806ac8346SIngo Molnar 4798425091fSRavikiran G Thirumalaiif X86_64 4808425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4818425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4828425091fSRavikiran G Thirumalai default y 4838425091fSRavikiran G Thirumalai ---help--- 4848425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4858425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4868425091fSRavikiran G Thirumalai systems out there.) 4878425091fSRavikiran G Thirumalai 4888425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4898425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 49044b111b5SSteffen Persvold Numascale NumaChip 4918425091fSRavikiran G Thirumalai ScaleMP vSMP 4928425091fSRavikiran G Thirumalai SGI Ultraviolet 4938425091fSRavikiran G Thirumalai 4948425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4958425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4968425091fSRavikiran G Thirumalaiendif 497c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 498c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 49944b111b5SSteffen Persvoldconfig X86_NUMACHIP 50044b111b5SSteffen Persvold bool "Numascale NumaChip" 50144b111b5SSteffen Persvold depends on X86_64 50244b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 50344b111b5SSteffen Persvold depends on NUMA 50444b111b5SSteffen Persvold depends on SMP 50544b111b5SSteffen Persvold depends on X86_X2APIC 506f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 50744b111b5SSteffen Persvold ---help--- 50844b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 50944b111b5SSteffen Persvold enable more than ~168 cores. 51044b111b5SSteffen Persvold If you don't have one of these, you should say N here. 51103b48632SNick Piggin 5126a48565eSIngo Molnarconfig X86_VSMP 513c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5146276a074SBorislav Petkov select HYPERVISOR_GUEST 5156a48565eSIngo Molnar select PARAVIRT 5166a48565eSIngo Molnar depends on X86_64 && PCI 517c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 518ead91d4bSShai Fultheim depends on SMP 5198f9ca475SIngo Molnar ---help--- 5206a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5216a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5226a48565eSIngo Molnar if you have one of these machines. 5236a48565eSIngo Molnar 524c5c606d9SRavikiran G Thirumalaiconfig X86_UV 525c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 526c5c606d9SRavikiran G Thirumalai depends on X86_64 527c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 52854c28d29SJack Steiner depends on NUMA 5291ecb4ae5SAndrew Morton depends on EFI 5309d6c26e7SSuresh Siddha depends on X86_X2APIC 5311222e564SIngo Molnar depends on PCI 532c5c606d9SRavikiran G Thirumalai ---help--- 533c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 534c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 535c5c606d9SRavikiran G Thirumalai 536c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 537c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 538506f1d07SSam Ravnborg 539ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 540ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 541cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 542ddd70cf9SJun Nakajima ---help--- 543ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 544ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 545ddd70cf9SJun Nakajima Goldfish emulator say N here. 546ddd70cf9SJun Nakajima 547c751e17bSThomas Gleixnerconfig X86_INTEL_CE 548c751e17bSThomas Gleixner bool "CE4100 TV platform" 549c751e17bSThomas Gleixner depends on PCI 550c751e17bSThomas Gleixner depends on PCI_GODIRECT 5516084a6e2SJiang Liu depends on X86_IO_APIC 552c751e17bSThomas Gleixner depends on X86_32 553c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 55437bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 555da6b737bSSebastian Andrzej Siewior select OF 556da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 557c751e17bSThomas Gleixner ---help--- 558c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 559c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 560c751e17bSThomas Gleixner boxes and media devices. 561c751e17bSThomas Gleixner 5624cb9b00fSDavid Cohenconfig X86_INTEL_MID 56343605ef1SAlan Cox bool "Intel MID platform support" 56443605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 565edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5661ea7c673SAlan Cox depends on PCI 5673fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5681ea7c673SAlan Cox depends on X86_IO_APIC 5697c9c3a1eSAlan Cox select SFI 5704cb9b00fSDavid Cohen select I2C 5717c9c3a1eSAlan Cox select DW_APB_TIMER 5721ea7c673SAlan Cox select APB_TIMER 5731ea7c673SAlan Cox select INTEL_SCU_IPC 57415a713dfSMika Westerberg select MFD_INTEL_MSIC 5751ea7c673SAlan Cox ---help--- 5764cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5774cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5784cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5791ea7c673SAlan Cox 5804cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5814cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 58243605ef1SAlan Cox 5838bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5848bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5858bbc2a13SBryan O'Donoghue depends on X86_32 5868bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5878bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5888bbc2a13SBryan O'Donoghue depends on X86_TSC 5898bbc2a13SBryan O'Donoghue depends on PCI 5908bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5918bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5928bbc2a13SBryan O'Donoghue select IOSF_MBI 5938bbc2a13SBryan O'Donoghue select INTEL_IMR 5949ab6eb51SAndy Shevchenko select COMMON_CLK 5958bbc2a13SBryan O'Donoghue ---help--- 5968bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5978bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5988bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5998bbc2a13SBryan O'Donoghue 6003d48aab1SMika Westerbergconfig X86_INTEL_LPSS 6013d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 602eebb3e8dSAndy Shevchenko depends on X86 && ACPI 6033d48aab1SMika Westerberg select COMMON_CLK 6040f531431SMathias Nyman select PINCTRL 605eebb3e8dSAndy Shevchenko select IOSF_MBI 6063d48aab1SMika Westerberg ---help--- 6073d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6083d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6090f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6100f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6113d48aab1SMika Westerberg 61292082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 61392082a88SKen Xue bool "AMD ACPI2Platform devices support" 61492082a88SKen Xue depends on ACPI 61592082a88SKen Xue select COMMON_CLK 61692082a88SKen Xue select PINCTRL 61792082a88SKen Xue ---help--- 61892082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 61992082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 62092082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 62192082a88SKen Xue implemented under PINCTRL subsystem. 62292082a88SKen Xue 623ced3ce76SDavid E. Boxconfig IOSF_MBI 624ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 625ced3ce76SDavid E. Box depends on PCI 626ced3ce76SDavid E. Box ---help--- 627ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 628ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 629ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 630ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 631ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 632ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 633ced3ce76SDavid E. Box This list is not meant to be exclusive. 634ced3ce76SDavid E. Box - BayTrail 635ced3ce76SDavid E. Box - Braswell 636ced3ce76SDavid E. Box - Quark 637ced3ce76SDavid E. Box 638ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 639ced3ce76SDavid E. Box 640ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 641ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 642ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 643ed2226bdSDavid E. Box ---help--- 644ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 645ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 646ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 647ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 648ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 649ed2226bdSDavid E. Box device they want to access. 650ed2226bdSDavid E. Box 651ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 652ed2226bdSDavid E. Box 653c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 654c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 655506f1d07SSam Ravnborg depends on X86_32 656c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 657c5c606d9SRavikiran G Thirumalai select M486 658c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 659c5c606d9SRavikiran G Thirumalai ---help--- 660c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 661c5c606d9SRavikiran G Thirumalai as R-8610-(G). 662c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 663c5c606d9SRavikiran G Thirumalai 664e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6659c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6669c398017SIngo Molnar depends on X86_32 && SMP 667c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6688f9ca475SIngo Molnar ---help--- 669b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 670b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 671b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 672b5660ba7SH. Peter Anvin one and will fallback to default. 673d49c4288SYinghai Lu 674c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 675d49c4288SYinghai Lu 676d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6776fc108a0SJan Beulich def_bool y 678d949f36fSLinus Torvalds # MCE code calls memory_failure(): 679d949f36fSLinus Torvalds depends on X86_MCE 680d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 681d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 682d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 683d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 684d949f36fSLinus Torvalds 68583125a3aSAlessandro Rubiniconfig STA2X11 68683125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 68783125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 688b6e05477SChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 68983125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 69083125a3aSAlessandro Rubini select X86_DMA_REMAP 69183125a3aSAlessandro Rubini select SWIOTLB 69283125a3aSAlessandro Rubini select MFD_STA2X11 6930145071bSLinus Walleij select GPIOLIB 69483125a3aSAlessandro Rubini default n 69583125a3aSAlessandro Rubini ---help--- 69683125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 69783125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 69883125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 69983125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 70083125a3aSAlessandro Rubini standard PC machines. 70183125a3aSAlessandro Rubini 70282148d1dSShérabconfig X86_32_IRIS 70382148d1dSShérab tristate "Eurobraille/Iris poweroff module" 70482148d1dSShérab depends on X86_32 70582148d1dSShérab ---help--- 70682148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 70782148d1dSShérab to shut themselves down properly. A special I/O sequence is 70882148d1dSShérab needed to do so, which is what this module does at 70982148d1dSShérab kernel shutdown. 71082148d1dSShérab 71182148d1dSShérab This is only for Iris machines from EuroBraille. 71282148d1dSShérab 71382148d1dSShérab If unused, say N. 71482148d1dSShérab 715ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7163c2362e6SHarvey Harrison def_bool y 7173c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 718a87d0914SKen Chen depends on X86 7198f9ca475SIngo Molnar ---help--- 720506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 721506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 722506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 723506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 724506f1d07SSam Ravnborg 725506f1d07SSam Ravnborg If in doubt, say "Y". 726506f1d07SSam Ravnborg 7276276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7286276a074SBorislav Petkov bool "Linux guest support" 7298f9ca475SIngo Molnar ---help--- 7306276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7316276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7326276a074SBorislav Petkov setup. 733506f1d07SSam Ravnborg 7346276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7356276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 736506f1d07SSam Ravnborg 7376276a074SBorislav Petkovif HYPERVISOR_GUEST 738506f1d07SSam Ravnborg 739e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 740e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7418f9ca475SIngo Molnar ---help--- 742e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 743e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 744e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 745e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 746e61bd94aSEduardo Pereira Habkost 7476276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7486276a074SBorislav Petkov bool "paravirt-ops debugging" 7496276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7506276a074SBorislav Petkov ---help--- 7516276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7526276a074SBorislav Petkov a paravirt_op is missing when it is called. 7536276a074SBorislav Petkov 754b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 755b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7566ea30386SKees Cook depends on PARAVIRT && SMP 757b4ecc126SJeremy Fitzhardinge ---help--- 758b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 759b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 760b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 761b4ecc126SJeremy Fitzhardinge 7624c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7634c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 764b4ecc126SJeremy Fitzhardinge 7654c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 766b4ecc126SJeremy Fitzhardinge 76745e898b7SWaiman Longconfig QUEUED_LOCK_STAT 76845e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 769cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 77045e898b7SWaiman Long ---help--- 77145e898b7SWaiman Long Enable the collection of statistical data on the slowpath 77245e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 77345e898b7SWaiman Long them on debugfs. 77445e898b7SWaiman Long 7756276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7766276a074SBorislav Petkov 7776276a074SBorislav Petkovconfig KVM_GUEST 7786276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7796276a074SBorislav Petkov depends on PARAVIRT 7806276a074SBorislav Petkov select PARAVIRT_CLOCK 7816276a074SBorislav Petkov default y 7826276a074SBorislav Petkov ---help--- 7836276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7846276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7856276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7866276a074SBorislav Petkov underlying device model, the host provides the guest with 7876276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7886276a074SBorislav Petkov 7891e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7901e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7911e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7921e20eb85SSrivatsa Vaddagiri default n 7931e20eb85SSrivatsa Vaddagiri ---help--- 7941e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7951e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7961e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7971e20eb85SSrivatsa Vaddagiri 7986276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7996276a074SBorislav Petkov bool "Paravirtual steal time accounting" 8006276a074SBorislav Petkov depends on PARAVIRT 8016276a074SBorislav Petkov default n 8026276a074SBorislav Petkov ---help--- 8036276a074SBorislav Petkov Select this option to enable fine granularity task steal time 8046276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 8056276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8066276a074SBorislav Petkov that, there can be a small performance impact. 8076276a074SBorislav Petkov 8086276a074SBorislav Petkov If in doubt, say N here. 8096276a074SBorislav Petkov 8107af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8117af192c9SGerd Hoffmann bool 8127af192c9SGerd Hoffmann 8134a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8144a362601SJan Kiszka bool "Jailhouse non-root cell support" 815abde587bSArnd Bergmann depends on X86_64 && PCI 81687e65d05SJan Kiszka select X86_PM_TIMER 8174a362601SJan Kiszka ---help--- 8184a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8194a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8204a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8214a362601SJan Kiszka 8226276a074SBorislav Petkovendif #HYPERVISOR_GUEST 82397349135SJeremy Fitzhardinge 82408677214SYinghai Luconfig NO_BOOTMEM 825774ea0bcSYinghai Lu def_bool y 82608677214SYinghai Lu 827506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 828506f1d07SSam Ravnborg 829506f1d07SSam Ravnborgconfig HPET_TIMER 8303c2362e6SHarvey Harrison def_bool X86_64 831506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8328f9ca475SIngo Molnar ---help--- 833506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 834506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 835506f1d07SSam Ravnborg present. 836506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 837506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 838506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8394e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8404e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 841506f1d07SSam Ravnborg 842506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 843506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 844506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 845506f1d07SSam Ravnborg 846506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 847506f1d07SSam Ravnborg 848506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8493c2362e6SHarvey Harrison def_bool y 8509d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 851506f1d07SSam Ravnborg 852bb24c471SJacob Panconfig APB_TIMER 853933b9463SAlan Cox def_bool y if X86_INTEL_MID 854933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 85506c3df49SJamie Iles select DW_APB_TIMER 856a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 857bb24c471SJacob Pan help 858bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 859bb24c471SJacob Pan The APBT provides a stable time base on SMP 860bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 861bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 862bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 863bb24c471SJacob Pan 8646a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 865506f1d07SSam Ravnborg# The code disables itself when not needed. 8667ae9392cSThomas Petazzoniconfig DMI 8677ae9392cSThomas Petazzoni default y 868cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8696a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8708f9ca475SIngo Molnar ---help--- 8717ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8727ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8737ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8747ae9392cSThomas Petazzoni BIOS code. 8757ae9392cSThomas Petazzoni 876506f1d07SSam Ravnborgconfig GART_IOMMU 87738901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 878506f1d07SSam Ravnborg select SWIOTLB 87923ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8808f9ca475SIngo Molnar ---help--- 881ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 882ced3c42cSIngo Molnar GART based hardware IOMMUs. 883ced3c42cSIngo Molnar 884ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 885ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 886ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 887ced3c42cSIngo Molnar 888ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 889ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 890ced3c42cSIngo Molnar 891ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 892ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 893ced3c42cSIngo Molnar 32-bit limited device. 894ced3c42cSIngo Molnar 895ced3c42cSIngo Molnar If unsure, say Y. 896506f1d07SSam Ravnborg 897506f1d07SSam Ravnborgconfig CALGARY_IOMMU 898506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 899506f1d07SSam Ravnborg select SWIOTLB 9006ea30386SKees Cook depends on X86_64 && PCI 9018f9ca475SIngo Molnar ---help--- 902506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 903506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 904506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 905506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 906506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 907506f1d07SSam Ravnborg prevents them from going anywhere except their intended 908506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 909506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 910506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 911506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 912506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 913506f1d07SSam Ravnborg If unsure, say Y. 914506f1d07SSam Ravnborg 915506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9163c2362e6SHarvey Harrison def_bool y 9173c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 918506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9198f9ca475SIngo Molnar ---help--- 920506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 921506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 922506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 923506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 924506f1d07SSam Ravnborg If unsure, say Y. 925506f1d07SSam Ravnborg 926506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 927506f1d07SSam Ravnborgconfig SWIOTLB 928a1afd01cSJoerg Roedel def_bool y if X86_64 9298f9ca475SIngo Molnar ---help--- 930506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9314454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9324454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9334454d327SJoe Millenbach with more than 3 GB of memory. 9344454d327SJoe Millenbach If unsure, say Y. 935506f1d07SSam Ravnborg 936a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9373120e25eSJan Beulich def_bool y 9383120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 939d25e26b6SLinus Torvalds 9401184dc2fSMike Travisconfig MAXSMP 941ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9426ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 94336f5101aSMike Travis select CPUMASK_OFFSTACK 9448f9ca475SIngo Molnar ---help--- 945ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9461184dc2fSMike Travis If unsure, say N. 947506f1d07SSam Ravnborg 948aec6487eSIngo Molnar# 949aec6487eSIngo Molnar# The maximum number of CPUs supported: 950aec6487eSIngo Molnar# 951aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 952aec6487eSIngo Molnar# and which can be configured interactively in the 953aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 954aec6487eSIngo Molnar# 955aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on 956aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel. 957aec6487eSIngo Molnar# 958aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable 959aec6487eSIngo Molnar# interactive configuration. ) 960aec6487eSIngo Molnar# 961a0d0bb4dSRandy Dunlap 962aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN 963a0d0bb4dSRandy Dunlap int 964aec6487eSIngo Molnar default NR_CPUS_RANGE_END if MAXSMP 965a0d0bb4dSRandy Dunlap default 1 if !SMP 966a0d0bb4dSRandy Dunlap default 2 967a0d0bb4dSRandy Dunlap 968aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 969a0d0bb4dSRandy Dunlap int 970a0d0bb4dSRandy Dunlap depends on X86_32 971aec6487eSIngo Molnar default 64 if SMP && X86_BIGSMP 972aec6487eSIngo Molnar default 8 if SMP && !X86_BIGSMP 973a0d0bb4dSRandy Dunlap default 1 if !SMP 974a0d0bb4dSRandy Dunlap 975aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 976a0d0bb4dSRandy Dunlap int 977a0d0bb4dSRandy Dunlap depends on X86_64 978aec6487eSIngo Molnar default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 979aec6487eSIngo Molnar default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 980a0d0bb4dSRandy Dunlap default 1 if !SMP 981aec6487eSIngo Molnar 982aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 983aec6487eSIngo Molnar int 984aec6487eSIngo Molnar depends on X86_32 985aec6487eSIngo Molnar default 32 if X86_BIGSMP 986aec6487eSIngo Molnar default 8 if SMP 987aec6487eSIngo Molnar default 1 if !SMP 988aec6487eSIngo Molnar 989aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 990aec6487eSIngo Molnar int 991aec6487eSIngo Molnar depends on X86_64 992a0d0bb4dSRandy Dunlap default 8192 if MAXSMP 993a0d0bb4dSRandy Dunlap default 64 if SMP 994aec6487eSIngo Molnar default 1 if !SMP 995a0d0bb4dSRandy Dunlap 996506f1d07SSam Ravnborgconfig NR_CPUS 99736f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 998aec6487eSIngo Molnar range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 999aec6487eSIngo Molnar default NR_CPUS_DEFAULT 10008f9ca475SIngo Molnar ---help--- 1001506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 1002bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 1003cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 1004506f1d07SSam Ravnborg minimum value which makes sense is 2. 1005506f1d07SSam Ravnborg 1006aec6487eSIngo Molnar This is purely to save memory: each supported CPU adds about 8KB 1007aec6487eSIngo Molnar to the kernel image. 1008506f1d07SSam Ravnborg 1009506f1d07SSam Ravnborgconfig SCHED_SMT 1010506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 1011c8e56d20SBorislav Petkov depends on SMP 10128f9ca475SIngo Molnar ---help--- 1013506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 1014506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 1015506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 1016506f1d07SSam Ravnborg N here. 1017506f1d07SSam Ravnborg 1018506f1d07SSam Ravnborgconfig SCHED_MC 10193c2362e6SHarvey Harrison def_bool y 10203c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 1021c8e56d20SBorislav Petkov depends on SMP 10228f9ca475SIngo Molnar ---help--- 1023506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 1024506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 1025506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 1026506f1d07SSam Ravnborg 1027de966cf4STim Chenconfig SCHED_MC_PRIO 1028de966cf4STim Chen bool "CPU core priorities scheduler support" 10290a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 10300a21fc12SIngo Molnar select X86_INTEL_PSTATE 10310a21fc12SIngo Molnar select CPU_FREQ 1032de966cf4STim Chen default y 10335e76b2abSTim Chen ---help--- 1034de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1035de966cf4STim Chen core ordering determined at manufacturing time, which allows 1036de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1037de966cf4STim Chen single threaded workloads) than others. 1038de966cf4STim Chen 1039de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1040de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1041de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1042de966cf4STim Chen overall system performance can be achieved. 1043de966cf4STim Chen 1044de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1045de966cf4STim Chen 1046de966cf4STim Chen If unsure say Y here. 10475e76b2abSTim Chen 1048506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 1049506f1d07SSam Ravnborg 105030b8b006SThomas Gleixnerconfig UP_LATE_INIT 105130b8b006SThomas Gleixner def_bool y 1052ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 105330b8b006SThomas Gleixner 1054506f1d07SSam Ravnborgconfig X86_UP_APIC 105550849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 105650849eefSJan Beulich default PCI_MSI 105738a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10588f9ca475SIngo Molnar ---help--- 1059506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1060506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1061506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1062506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1063506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1064506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1065506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1066506f1d07SSam Ravnborg lockups. 1067506f1d07SSam Ravnborg 1068506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1069506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1070506f1d07SSam Ravnborg depends on X86_UP_APIC 10718f9ca475SIngo Molnar ---help--- 1072506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1073506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1074506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1075506f1d07SSam Ravnborg 1076506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1077506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1078506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1079506f1d07SSam Ravnborg 1080506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10813c2362e6SHarvey Harrison def_bool y 10820dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1083b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 108452f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1085506f1d07SSam Ravnborg 1086506f1d07SSam Ravnborgconfig X86_IO_APIC 1087b1da1e71SJan Beulich def_bool y 1088b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1089506f1d07SSam Ravnborg 109041b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 109141b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 109241b9eb26SStefan Assmann depends on X86_IO_APIC 10938f9ca475SIngo Molnar ---help--- 109441b9eb26SStefan Assmann This option enables a workaround that fixes a source of 109541b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 109641b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 109741b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 109841b9eb26SStefan Assmann 109941b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 110041b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 110141b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 110241b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 110341b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 110441b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 110541b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 110641b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 110741b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 110841b9eb26SStefan Assmann down (vital) interrupt lines. 110941b9eb26SStefan Assmann 111041b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 111141b9eb26SStefan Assmann increased on these systems. 111241b9eb26SStefan Assmann 1113506f1d07SSam Ravnborgconfig X86_MCE 1114bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1115648ed940SChen, Gong select GENERIC_ALLOCATOR 1116e57dbaf7SBorislav Petkov default y 1117506f1d07SSam Ravnborg ---help--- 1118bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1119bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1120506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1121bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 11224efc0670SAndi Kleen 11235de97c9fSTony Luckconfig X86_MCELOG_LEGACY 11245de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 11255de97c9fSTony Luck depends on X86_MCE 11265de97c9fSTony Luck ---help--- 11275de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 11285de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 11295de97c9fSTony Luck rasdaemon solution. 11305de97c9fSTony Luck 1131506f1d07SSam Ravnborgconfig X86_MCE_INTEL 11323c2362e6SHarvey Harrison def_bool y 11333c2362e6SHarvey Harrison prompt "Intel MCE features" 1134c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 11358f9ca475SIngo Molnar ---help--- 1136506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1137506f1d07SSam Ravnborg the thermal monitor. 1138506f1d07SSam Ravnborg 1139506f1d07SSam Ravnborgconfig X86_MCE_AMD 11403c2362e6SHarvey Harrison def_bool y 11413c2362e6SHarvey Harrison prompt "AMD MCE features" 1142f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11438f9ca475SIngo Molnar ---help--- 1144506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1145506f1d07SSam Ravnborg the DRAM Error Threshold. 1146506f1d07SSam Ravnborg 11474efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11486fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1149c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11504efc0670SAndi Kleen ---help--- 11514efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11525065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11534efc0670SAndi Kleen line. 11544efc0670SAndi Kleen 1155b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1156b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11576fc108a0SJan Beulich def_bool y 1158b2762686SAndi Kleen 1159ea149b36SAndi Kleenconfig X86_MCE_INJECT 1160bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1161ea149b36SAndi Kleen tristate "Machine check injector support" 1162ea149b36SAndi Kleen ---help--- 1163ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1164ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1165ea149b36SAndi Kleen QA it is safe to say n. 1166ea149b36SAndi Kleen 11674efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11684efc0670SAndi Kleen def_bool y 11695bb38adcSAndi Kleen depends on X86_MCE_INTEL 11704efc0670SAndi Kleen 117107dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1172e633c65aSKan Liang 11735aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11741e642812SIngo Molnar bool "Legacy VM86 support" 11755aef51c3SAndy Lutomirski default n 1176506f1d07SSam Ravnborg depends on X86_32 11778f9ca475SIngo Molnar ---help--- 11785aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11795aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11805aef51c3SAndy Lutomirski 11815aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11825aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11835aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11845aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11855aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11861e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11871e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11881e642812SIngo Molnar mode might be faster than emulation and you might want to 11891e642812SIngo Molnar enable this option. 11905aef51c3SAndy Lutomirski 11911e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11921e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11931e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11941e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11955aef51c3SAndy Lutomirski 11961e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11971e642812SIngo Molnar and slows down exception handling a tiny bit. 11985aef51c3SAndy Lutomirski 11991e642812SIngo Molnar If unsure, say N here. 12005aef51c3SAndy Lutomirski 12015aef51c3SAndy Lutomirskiconfig VM86 12025aef51c3SAndy Lutomirski bool 12035aef51c3SAndy Lutomirski default X86_LEGACY_VM86 120434273f41SH. Peter Anvin 120534273f41SH. Peter Anvinconfig X86_16BIT 120634273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 120734273f41SH. Peter Anvin default y 1208a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 120934273f41SH. Peter Anvin ---help--- 121034273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 121134273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 121234273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 121334273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 121434273f41SH. Peter Anvin 121534273f41SH. Peter Anvinconfig X86_ESPFIX32 121634273f41SH. Peter Anvin def_bool y 121734273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1218506f1d07SSam Ravnborg 1219197725deSH. Peter Anvinconfig X86_ESPFIX64 1220197725deSH. Peter Anvin def_bool y 122134273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1222506f1d07SSam Ravnborg 12231ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 12241ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 12251ad83c85SAndy Lutomirski default y 12261ad83c85SAndy Lutomirski depends on X86_64 12271ad83c85SAndy Lutomirski ---help--- 12281ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 12291ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 12301ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 12311ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 12321ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 12331ad83c85SAndy Lutomirski 0xffffffffff600?00. 12341ad83c85SAndy Lutomirski 12351ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12361ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12371ad83c85SAndy Lutomirski 12381ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12391ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12401ad83c85SAndy Lutomirski 1241506f1d07SSam Ravnborgconfig TOSHIBA 1242506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1243506f1d07SSam Ravnborg depends on X86_32 1244506f1d07SSam Ravnborg ---help--- 1245506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1246506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1247506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1248506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1249506f1d07SSam Ravnborg 1250506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1251506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1252506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1253506f1d07SSam Ravnborg 1254506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1255506f1d07SSam Ravnborg Say N otherwise. 1256506f1d07SSam Ravnborg 1257506f1d07SSam Ravnborgconfig I8K 1258039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1259949a9d70SJean Delvare select HWMON 1260039ae585SPali Rohár select SENSORS_DELL_SMM 1261506f1d07SSam Ravnborg ---help--- 1262039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1263039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1264039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1265039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1266039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1267039ae585SPali Rohár needed userspace package i8kutils. 1268506f1d07SSam Ravnborg 1269039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1270039ae585SPali Rohár use userspace package i8kutils. 1271506f1d07SSam Ravnborg Say N otherwise. 1272506f1d07SSam Ravnborg 1273506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12749ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12759ba16087SJan Beulich depends on X86_32 1276506f1d07SSam Ravnborg ---help--- 1277506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1278506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1279506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1280506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1281506f1d07SSam Ravnborg system. 1282506f1d07SSam Ravnborg 1283506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12845e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1285506f1d07SSam Ravnborg 1286506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1287506f1d07SSam Ravnborg enable this option even if you don't need it. 1288506f1d07SSam Ravnborg Say N otherwise. 1289506f1d07SSam Ravnborg 1290506f1d07SSam Ravnborgconfig MICROCODE 12919a2bc335SBorislav Petkov bool "CPU microcode loading support" 12929a2bc335SBorislav Petkov default y 129380030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1294506f1d07SSam Ravnborg select FW_LOADER 1295506f1d07SSam Ravnborg ---help--- 1296506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12975f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12985f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12995f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 13005f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 13015f9c01aaSBorislav Petkov the Linux kernel. 1302506f1d07SSam Ravnborg 13035f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 13041897a969SJaak Ristioja in Documentation/x86/microcode.txt. For that you need to enable 13055f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 13065f9c01aaSBorislav Petkov initrd for microcode blobs. 1307506f1d07SSam Ravnborg 1308c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1309c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1310c508c46eSBenjamin Gilbert config option. 1311506f1d07SSam Ravnborg 13128d86f390SPeter Orubaconfig MICROCODE_INTEL 1313e43f6e67SBorislav Petkov bool "Intel microcode loading support" 13148d86f390SPeter Oruba depends on MICROCODE 13158d86f390SPeter Oruba default MICROCODE 13168d86f390SPeter Oruba select FW_LOADER 13178f9ca475SIngo Molnar ---help--- 13188d86f390SPeter Oruba This options enables microcode patch loading support for Intel 13198d86f390SPeter Oruba processors. 13208d86f390SPeter Oruba 1321b8989db9SAlan For the current Intel microcode data package go to 1322b8989db9SAlan <https://downloadcenter.intel.com> and search for 1323b8989db9SAlan 'Linux Processor Microcode Data File'. 13248d86f390SPeter Oruba 132580cc9f10SPeter Orubaconfig MICROCODE_AMD 1326e43f6e67SBorislav Petkov bool "AMD microcode loading support" 132780cc9f10SPeter Oruba depends on MICROCODE 132880cc9f10SPeter Oruba select FW_LOADER 13298f9ca475SIngo Molnar ---help--- 133080cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 133180cc9f10SPeter Oruba processors will be enabled. 133280cc9f10SPeter Oruba 1333506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 13343c2362e6SHarvey Harrison def_bool y 1335506f1d07SSam Ravnborg depends on MICROCODE 1336506f1d07SSam Ravnborg 1337506f1d07SSam Ravnborgconfig X86_MSR 1338506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13398f9ca475SIngo Molnar ---help--- 1340506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1341506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1342506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1343506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1344506f1d07SSam Ravnborg systems. 1345506f1d07SSam Ravnborg 1346506f1d07SSam Ravnborgconfig X86_CPUID 1347506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13488f9ca475SIngo Molnar ---help--- 1349506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1350506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1351506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1352506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1353506f1d07SSam Ravnborg 1354506f1d07SSam Ravnborgchoice 1355506f1d07SSam Ravnborg prompt "High Memory Support" 13566fc108a0SJan Beulich default HIGHMEM4G 1357506f1d07SSam Ravnborg depends on X86_32 1358506f1d07SSam Ravnborg 1359506f1d07SSam Ravnborgconfig NOHIGHMEM 1360506f1d07SSam Ravnborg bool "off" 1361506f1d07SSam Ravnborg ---help--- 1362506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1363506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1364506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1365506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1366506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1367506f1d07SSam Ravnborg "high memory". 1368506f1d07SSam Ravnborg 1369506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1370506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1371506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1372506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1373506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1374506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1375506f1d07SSam Ravnborg possible. 1376506f1d07SSam Ravnborg 1377506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1378506f1d07SSam Ravnborg answer "4GB" here. 1379506f1d07SSam Ravnborg 1380506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1381506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1382506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1383506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1384506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1385506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1386506f1d07SSam Ravnborg 1387506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1388506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1389506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1390506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1391506f1d07SSam Ravnborg kernel at boot time.) 1392506f1d07SSam Ravnborg 1393506f1d07SSam Ravnborg If unsure, say "off". 1394506f1d07SSam Ravnborg 1395506f1d07SSam Ravnborgconfig HIGHMEM4G 1396506f1d07SSam Ravnborg bool "4GB" 13978f9ca475SIngo Molnar ---help--- 1398506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1399506f1d07SSam Ravnborg gigabytes of physical RAM. 1400506f1d07SSam Ravnborg 1401506f1d07SSam Ravnborgconfig HIGHMEM64G 1402506f1d07SSam Ravnborg bool "64GB" 140369b8d3fcSMatthew Whitehead depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1404506f1d07SSam Ravnborg select X86_PAE 14058f9ca475SIngo Molnar ---help--- 1406506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1407506f1d07SSam Ravnborg gigabytes of physical RAM. 1408506f1d07SSam Ravnborg 1409506f1d07SSam Ravnborgendchoice 1410506f1d07SSam Ravnborg 1411506f1d07SSam Ravnborgchoice 14126a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1413506f1d07SSam Ravnborg default VMSPLIT_3G 1414506f1d07SSam Ravnborg depends on X86_32 14158f9ca475SIngo Molnar ---help--- 1416506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1417506f1d07SSam Ravnborg 1418506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1419506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1420506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1421506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1422506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1423506f1d07SSam Ravnborg available to user programs, making the address space there 1424506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1425506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1426506f1d07SSam Ravnborg kernel modules. 1427506f1d07SSam Ravnborg 1428506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1429506f1d07SSam Ravnborg option alone! 1430506f1d07SSam Ravnborg 1431506f1d07SSam Ravnborg config VMSPLIT_3G 1432506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1433506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1434506f1d07SSam Ravnborg depends on !X86_PAE 1435506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1436506f1d07SSam Ravnborg config VMSPLIT_2G 1437506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1438506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1439506f1d07SSam Ravnborg depends on !X86_PAE 1440506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1441506f1d07SSam Ravnborg config VMSPLIT_1G 1442506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1443506f1d07SSam Ravnborgendchoice 1444506f1d07SSam Ravnborg 1445506f1d07SSam Ravnborgconfig PAGE_OFFSET 1446506f1d07SSam Ravnborg hex 1447506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1448506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1449506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1450506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1451506f1d07SSam Ravnborg default 0xC0000000 1452506f1d07SSam Ravnborg depends on X86_32 1453506f1d07SSam Ravnborg 1454506f1d07SSam Ravnborgconfig HIGHMEM 14553c2362e6SHarvey Harrison def_bool y 1456506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1457506f1d07SSam Ravnborg 1458506f1d07SSam Ravnborgconfig X86_PAE 14599ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1460506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 14619d99c712SChristian Melki select SWIOTLB 14628f9ca475SIngo Molnar ---help--- 1463506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1464506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1465506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1466506f1d07SSam Ravnborg consumes more pagetable space per process. 1467506f1d07SSam Ravnborg 146877ef56e4SKirill A. Shutemovconfig X86_5LEVEL 146977ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 1470eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 1471162434e7SKirill A. Shutemov select SPARSEMEM_VMEMMAP 147277ef56e4SKirill A. Shutemov depends on X86_64 147377ef56e4SKirill A. Shutemov ---help--- 147477ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 147577ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 147677ef56e4SKirill A. Shutemov physical address space. 147777ef56e4SKirill A. Shutemov 147877ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 147977ef56e4SKirill A. Shutemov 14806657fca0SKirill A. Shutemov A kernel with the option enabled can be booted on machines that 14816657fca0SKirill A. Shutemov support 4- or 5-level paging. 148277ef56e4SKirill A. Shutemov 148377ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 148477ef56e4SKirill A. Shutemov information. 148577ef56e4SKirill A. Shutemov 148677ef56e4SKirill A. Shutemov Say N if unsure. 148777ef56e4SKirill A. Shutemov 1488600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14893120e25eSJan Beulich def_bool y 14903120e25eSJan Beulich depends on X86_64 || X86_PAE 1491600715dcSJeremy Fitzhardinge 149266f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14933120e25eSJan Beulich def_bool y 14943120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 149566f2b061SFUJITA Tomonori 149610971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1497e5008abeSLuis R. Rodriguez def_bool y 14984675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 14998f9ca475SIngo Molnar ---help--- 150010971ab2SIngo Molnar Certain kernel features effectively disable kernel 150110971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 150210971ab2SIngo Molnar supports them), so don't confuse the user by printing 150310971ab2SIngo Molnar that we have them enabled. 15049e899816SNick Piggin 15057744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 15067744ccdbSTom Lendacky def_bool y 15077744ccdbSTom Lendacky 15087744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 15097744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 15107744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 15117744ccdbSTom Lendacky ---help--- 15127744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 15137744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 15147744ccdbSTom Lendacky Encryption (SME). 15157744ccdbSTom Lendacky 15167744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 15177744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 15187744ccdbSTom Lendacky default y 15197744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 15207744ccdbSTom Lendacky ---help--- 15217744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 15227744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 15237744ccdbSTom Lendacky 15247744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 15257744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 15267744ccdbSTom Lendacky 15277744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 15287744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 15297744ccdbSTom Lendacky 1530f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1531f88a68faSTom Lendacky def_bool y 1532f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1533f88a68faSTom Lendacky 1534506f1d07SSam Ravnborg# Common NUMA Features 1535506f1d07SSam Ravnborgconfig NUMA 1536fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1537506f1d07SSam Ravnborg depends on SMP 1538b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1539b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15408f9ca475SIngo Molnar ---help--- 1541506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1542fd51b2d7SKOSAKI Motohiro 1543506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1544506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1545506f1d07SSam Ravnborg NUMA awareness to the kernel. 1546506f1d07SSam Ravnborg 1547c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1548fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1549fd51b2d7SKOSAKI Motohiro 1550b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15517cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1552fd51b2d7SKOSAKI Motohiro 1553fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1554506f1d07SSam Ravnborg 1555eec1d4faSHans Rosenfeldconfig AMD_NUMA 15563c2362e6SHarvey Harrison def_bool y 15573c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15585da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15598f9ca475SIngo Molnar ---help--- 1560eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1561eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1562eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1563eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1564eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1565506f1d07SSam Ravnborg 1566506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15673c2362e6SHarvey Harrison def_bool y 15683c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1569506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1570506f1d07SSam Ravnborg select ACPI_NUMA 15718f9ca475SIngo Molnar ---help--- 1572506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1573506f1d07SSam Ravnborg 15746ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15756ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15766ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15776ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15786ec6e0d9SSuresh Siddha# for details. 15796ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15806ec6e0d9SSuresh Siddha def_bool y 15816ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15826ec6e0d9SSuresh Siddha 1583506f1d07SSam Ravnborgconfig NUMA_EMU 1584506f1d07SSam Ravnborg bool "NUMA emulation" 15851b7e03efSTejun Heo depends on NUMA 15868f9ca475SIngo Molnar ---help--- 1587506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1588506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1589506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1590506f1d07SSam Ravnborg 1591506f1d07SSam Ravnborgconfig NODES_SHIFT 1592d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 159351591e31SDavid Rientjes range 1 10 159451591e31SDavid Rientjes default "10" if MAXSMP 1595506f1d07SSam Ravnborg default "6" if X86_64 1596506f1d07SSam Ravnborg default "3" 1597506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15988f9ca475SIngo Molnar ---help--- 15991184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1600692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1601506f1d07SSam Ravnborg 1602506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 16033c2362e6SHarvey Harrison def_bool y 1604506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1605506f1d07SSam Ravnborg 1606506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1607506f1d07SSam Ravnborg def_bool y 16083b16651fSTejun Heo depends on X86_32 && !NUMA 1609506f1d07SSam Ravnborg 1610506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1611506f1d07SSam Ravnborg def_bool y 1612b263295dSChristoph Lameter depends on NUMA && X86_32 1613506f1d07SSam Ravnborg 1614506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1615506f1d07SSam Ravnborg def_bool y 1616b263295dSChristoph Lameter depends on NUMA && X86_32 1617b263295dSChristoph Lameter 1618506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1619506f1d07SSam Ravnborg def_bool y 16206ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1621506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1622506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1623506f1d07SSam Ravnborg 16243b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 16253b16651fSTejun Heo def_bool y 16263b16651fSTejun Heo depends on X86_64 16273b16651fSTejun Heo 1628506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1629506f1d07SSam Ravnborg def_bool y 1630b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1631506f1d07SSam Ravnborg 1632506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1633a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16343120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1635a0842b70SToshi Kani help 1636a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1637a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1638a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1639506f1d07SSam Ravnborg 16403b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16413b16651fSTejun Heo def_bool y 16423b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16433b16651fSTejun Heo 1644a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1645a29815a3SAvi Kivity hex 1646a29815a3SAvi Kivity default 0 if X86_32 1647a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1648a29815a3SAvi Kivity 1649506f1d07SSam Ravnborgsource "mm/Kconfig" 1650506f1d07SSam Ravnborg 16517a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16527a67832cSDan Williams bool 16537a67832cSDan Williams 1654ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16557a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16569f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16579f53f9faSDan Williams depends on BLK_DEV 16587a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16599f53f9faSDan Williams select LIBNVDIMM 1660ec776ef6SChristoph Hellwig help 1661ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1662ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1663ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1664ec776ef6SChristoph Hellwig they can be used for persistent storage. 1665ec776ef6SChristoph Hellwig 1666ec776ef6SChristoph Hellwig Say Y if unsure. 1667ec776ef6SChristoph Hellwig 1668506f1d07SSam Ravnborgconfig HIGHPTE 1669506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16706fc108a0SJan Beulich depends on HIGHMEM 16718f9ca475SIngo Molnar ---help--- 1672506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1673506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1674506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1675506f1d07SSam Ravnborg entries in high memory. 1676506f1d07SSam Ravnborg 16779f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16789f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16798f9ca475SIngo Molnar ---help--- 16809f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16819f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16829f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16839f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16849f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16859f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16869f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16878c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16889f077871SJeremy Fitzhardinge 16899f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16909f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16919f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16929f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16939f077871SJeremy Fitzhardinge 16949f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16959f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16969f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16979f077871SJeremy Fitzhardinge memory. 16989f077871SJeremy Fitzhardinge 1699c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1700c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1701c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1702c885df50SJeremy Fitzhardinge default y 17038f9ca475SIngo Molnar ---help--- 1704c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1705c885df50SJeremy Fitzhardinge on or off. 1706c885df50SJeremy Fitzhardinge 17079ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1708d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1709d0cd7425SH. Peter Anvin default 64 1710d0cd7425SH. Peter Anvin range 4 640 17118f9ca475SIngo Molnar ---help--- 1712d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1713fc381519SIngo Molnar 1714d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1715d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1716fc381519SIngo Molnar 1717d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1718d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1719d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1720d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1721fc381519SIngo Molnar 1722d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1723d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1724d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1725d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1726d0cd7425SH. Peter Anvin entire low memory range. 1727d0cd7425SH. Peter Anvin 1728d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1729d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1730d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1731d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1732d0cd7425SH. Peter Anvin typical corruption patterns. 1733d0cd7425SH. Peter Anvin 1734d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1735fc381519SIngo Molnar 1736506f1d07SSam Ravnborgconfig MATH_EMULATION 1737506f1d07SSam Ravnborg bool 1738a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1739506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1740506f1d07SSam Ravnborg ---help--- 1741506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1742506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1743506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1744506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1745506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1746506f1d07SSam Ravnborg coprocessor or this emulation. 1747506f1d07SSam Ravnborg 1748506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1749506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1750506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1751506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1752506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1753506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1754506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1755506f1d07SSam Ravnborg intend to use this kernel on different machines. 1756506f1d07SSam Ravnborg 1757506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1758506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1759506f1d07SSam Ravnborg 1760506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1761506f1d07SSam Ravnborg kernel, it won't hurt. 1762506f1d07SSam Ravnborg 1763506f1d07SSam Ravnborgconfig MTRR 17646fc108a0SJan Beulich def_bool y 17656a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1766506f1d07SSam Ravnborg ---help--- 1767506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1768506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1769506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1770506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1771506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1772506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1773506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1774506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1775506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1776506f1d07SSam Ravnborg 1777506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1778506f1d07SSam Ravnborg control registers on other processors can be easily supported 1779506f1d07SSam Ravnborg as well: 1780506f1d07SSam Ravnborg 1781506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1782506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1783506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1784506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1785506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1786506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1787506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1788506f1d07SSam Ravnborg 1789506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1790506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1791506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1792506f1d07SSam Ravnborg 1793506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1794506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1795506f1d07SSam Ravnborg 17967225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1797506f1d07SSam Ravnborg 179895ffa243SYinghai Luconfig MTRR_SANITIZER 17992ffb3501SYinghai Lu def_bool y 180095ffa243SYinghai Lu prompt "MTRR cleanup support" 180195ffa243SYinghai Lu depends on MTRR 18028f9ca475SIngo Molnar ---help--- 1803aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1804aba3728cSThomas Gleixner add writeback entries. 180595ffa243SYinghai Lu 1806aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1807692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1808aba3728cSThomas Gleixner mtrr_chunk_size. 180995ffa243SYinghai Lu 18102ffb3501SYinghai Lu If unsure, say Y. 181195ffa243SYinghai Lu 181295ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1813f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1814f5098d62SYinghai Lu range 0 1 1815f5098d62SYinghai Lu default "0" 181695ffa243SYinghai Lu depends on MTRR_SANITIZER 18178f9ca475SIngo Molnar ---help--- 1818f5098d62SYinghai Lu Enable mtrr cleanup default value 181995ffa243SYinghai Lu 182012031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 182112031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 182212031a62SYinghai Lu range 0 7 182312031a62SYinghai Lu default "1" 182412031a62SYinghai Lu depends on MTRR_SANITIZER 18258f9ca475SIngo Molnar ---help--- 182612031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1827aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 182812031a62SYinghai Lu 18292e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 18306fc108a0SJan Beulich def_bool y 18316a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 18322a8a2719SIngo Molnar depends on MTRR 18338f9ca475SIngo Molnar ---help--- 18342e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1835042b78e4SVenki Pallipadi 18362e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18372e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18382e5d9c85Svenkatesh.pallipadi@intel.com 18392e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1840042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18412e5d9c85Svenkatesh.pallipadi@intel.com 18422e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18432e5d9c85Svenkatesh.pallipadi@intel.com 184446cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 184546cf98cdSVenkatesh Pallipadi def_bool y 184646cf98cdSVenkatesh Pallipadi depends on X86_PAT 184746cf98cdSVenkatesh Pallipadi 1848628c6246SH. Peter Anvinconfig ARCH_RANDOM 1849628c6246SH. Peter Anvin def_bool y 1850628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1851628c6246SH. Peter Anvin ---help--- 1852628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1853628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1854628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1855628c6246SH. Peter Anvin secure hardware random number generator. 1856628c6246SH. Peter Anvin 185751ae4a2dSH. Peter Anvinconfig X86_SMAP 185851ae4a2dSH. Peter Anvin def_bool y 185951ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 186051ae4a2dSH. Peter Anvin ---help--- 186151ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 186251ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 186351ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 186451ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 186551ae4a2dSH. Peter Anvin 186651ae4a2dSH. Peter Anvin If unsure, say Y. 186751ae4a2dSH. Peter Anvin 1868aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1869796ebc81SRicardo Neri def_bool y 1870aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1871aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1872aa35f896SRicardo Neri ---help--- 1873aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1874aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1875796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1876796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1877796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1878796ebc81SRicardo Neri 1879796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1880796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1881796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1882796ebc81SRicardo Neri results are dummy. 1883aa35f896SRicardo Neri 188472e9b5feSDave Hansenconfig X86_INTEL_MPX 188572e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 188672e9b5feSDave Hansen def_bool n 1887df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1888df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1889df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 189072e9b5feSDave Hansen ---help--- 189172e9b5feSDave Hansen MPX provides hardware features that can be used in 189272e9b5feSDave Hansen conjunction with compiler-instrumented code to check 189372e9b5feSDave Hansen memory references. It is designed to detect buffer 189472e9b5feSDave Hansen overflow or underflow bugs. 189572e9b5feSDave Hansen 189672e9b5feSDave Hansen This option enables running applications which are 189772e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 189872e9b5feSDave Hansen itself inside the kernel or to protect the kernel 189972e9b5feSDave Hansen against bad memory references. 190072e9b5feSDave Hansen 190172e9b5feSDave Hansen Enabling this option will make the kernel larger: 190272e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 190372e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 190472e9b5feSDave Hansen will increase the kernel memory overhead of each 190572e9b5feSDave Hansen process and adds some branches to paths used during 190672e9b5feSDave Hansen exec() and munmap(). 190772e9b5feSDave Hansen 190872e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 190972e9b5feSDave Hansen 191072e9b5feSDave Hansen If unsure, say N. 191172e9b5feSDave Hansen 191235e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1913284244a9SDave Hansen prompt "Intel Memory Protection Keys" 191435e97790SDave Hansen def_bool y 1915284244a9SDave Hansen # Note: only available in 64-bit mode 191635e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 191752c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 191852c8e601SIngo Molnar select ARCH_HAS_PKEYS 1919284244a9SDave Hansen ---help--- 1920284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1921284244a9SDave Hansen page-based protections, but without requiring modification of the 1922284244a9SDave Hansen page tables when an application changes protection domains. 1923284244a9SDave Hansen 1924284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1925284244a9SDave Hansen 1926284244a9SDave Hansen If unsure, say y. 192735e97790SDave Hansen 1928506f1d07SSam Ravnborgconfig EFI 19299ba16087SJan Beulich bool "EFI runtime service support" 19305b83683fSHuang, Ying depends on ACPI 1931f6ce5002SSergey Vlasov select UCS2_STRING 1932022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1933506f1d07SSam Ravnborg ---help--- 19348b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1935506f1d07SSam Ravnborg available (such as the EFI variable services). 1936506f1d07SSam Ravnborg 19378b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19388b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19398b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19408b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19418b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19428b2cb7a8SHuang, Ying platforms. 1943506f1d07SSam Ravnborg 1944291f3632SMatt Flemingconfig EFI_STUB 1945291f3632SMatt Fleming bool "EFI stub support" 1946b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19477b2a583aSMatt Fleming select RELOCATABLE 1948291f3632SMatt Fleming ---help--- 1949291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1950291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1951291f3632SMatt Fleming 19524172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19530c759662SMatt Fleming 19547d453eeeSMatt Flemingconfig EFI_MIXED 19557d453eeeSMatt Fleming bool "EFI mixed-mode support" 19567d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19577d453eeeSMatt Fleming ---help--- 19587d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19597d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19607d453eeeSMatt Fleming mode. 19617d453eeeSMatt Fleming 19627d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19637d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19647d453eeeSMatt Fleming the EFI handover protocol must be used. 19657d453eeeSMatt Fleming 19667d453eeeSMatt Fleming If unsure, say N. 19677d453eeeSMatt Fleming 1968506f1d07SSam Ravnborgconfig SECCOMP 19693c2362e6SHarvey Harrison def_bool y 19703c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19718f9ca475SIngo Molnar ---help--- 1972506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1973506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1974506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1975506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1976506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1977506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19789c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1979506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1980506f1d07SSam Ravnborg defined by each seccomp mode. 1981506f1d07SSam Ravnborg 1982506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1983506f1d07SSam Ravnborg 1984506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1985506f1d07SSam Ravnborg 1986506f1d07SSam Ravnborgconfig KEXEC 1987506f1d07SSam Ravnborg bool "kexec system call" 19882965faa5SDave Young select KEXEC_CORE 19898f9ca475SIngo Molnar ---help--- 1990506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1991506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1992506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1993506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1994506f1d07SSam Ravnborg 1995506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1996506f1d07SSam Ravnborg 1997506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1998506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1999bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 2000bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 2001bf220695SGeert Uytterhoeven made. 2002506f1d07SSam Ravnborg 200374ca317cSVivek Goyalconfig KEXEC_FILE 200474ca317cSVivek Goyal bool "kexec file based system call" 20052965faa5SDave Young select KEXEC_CORE 200674ca317cSVivek Goyal select BUILD_BIN2C 200774ca317cSVivek Goyal depends on X86_64 200874ca317cSVivek Goyal depends on CRYPTO=y 200974ca317cSVivek Goyal depends on CRYPTO_SHA256=y 201074ca317cSVivek Goyal ---help--- 201174ca317cSVivek Goyal This is new version of kexec system call. This system call is 201274ca317cSVivek Goyal file based and takes file descriptors as system call argument 201374ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 201474ca317cSVivek Goyal accepted by previous system call. 201574ca317cSVivek Goyal 2016b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY 2017b799a09fSAKASHI Takahiro def_bool KEXEC_FILE 2018b799a09fSAKASHI Takahiro 20198e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 20208e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 202174ca317cSVivek Goyal depends on KEXEC_FILE 20228e7d8381SVivek Goyal ---help--- 20238e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 2024d8eb8940SBorislav Petkov the kexec_file_load() syscall. 20258e7d8381SVivek Goyal 2026d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 2027d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 2028d8eb8940SBorislav Petkov loaded in order for this to work. 20298e7d8381SVivek Goyal 20308e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 20318e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 20328e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 20338e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 20348e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 20358e7d8381SVivek Goyal ---help--- 20368e7d8381SVivek Goyal Enable bzImage signature verification support. 20378e7d8381SVivek Goyal 2038506f1d07SSam Ravnborgconfig CRASH_DUMP 203904b69447SPavel Machek bool "kernel crash dumps" 2040506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20418f9ca475SIngo Molnar ---help--- 2042506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2043506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2044506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2045506f1d07SSam Ravnborg a specially reserved region and then later executed after 2046506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2047506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2048506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2049506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2050506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2051506f1d07SSam Ravnborg 20523ab83521SHuang Yingconfig KEXEC_JUMP 20536ea30386SKees Cook bool "kexec jump" 2054fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20558f9ca475SIngo Molnar ---help--- 205689081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 205789081d17SHuang Ying code in physical address mode via KEXEC 20583ab83521SHuang Ying 2059506f1d07SSam Ravnborgconfig PHYSICAL_START 20606a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2061ceefccc9SH. Peter Anvin default "0x1000000" 20628f9ca475SIngo Molnar ---help--- 2063506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2064506f1d07SSam Ravnborg 2065506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2066506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2067506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2068506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2069506f1d07SSam Ravnborg address. 2070506f1d07SSam Ravnborg 2071506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2072506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2073506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2074506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2075506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2076506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2077506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2078506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2079506f1d07SSam Ravnborg 2080ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2081ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2082ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2083ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2084ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2085ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2086ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2087ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2088ceefccc9SH. Peter Anvin for more details about crash dumps. 2089506f1d07SSam Ravnborg 2090506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2091506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2092506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2093506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2094506f1d07SSam Ravnborg is present because there are users out there who continue to use 2095506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2096506f1d07SSam Ravnborg line. 2097506f1d07SSam Ravnborg 2098506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2099506f1d07SSam Ravnborg 2100506f1d07SSam Ravnborgconfig RELOCATABLE 210126717808SH. Peter Anvin bool "Build a relocatable kernel" 210226717808SH. Peter Anvin default y 21038f9ca475SIngo Molnar ---help--- 2104506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2105506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2106506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2107506f1d07SSam Ravnborg but are discarded at runtime. 2108506f1d07SSam Ravnborg 2109506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2110506f1d07SSam Ravnborg must live at a different physical address than the primary 2111506f1d07SSam Ravnborg kernel. 2112506f1d07SSam Ravnborg 2113506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2114506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 21158ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2116506f1d07SSam Ravnborg 21178ab3820fSKees Cookconfig RANDOMIZE_BASE 2118e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 21198ab3820fSKees Cook depends on RELOCATABLE 21206807c846SIngo Molnar default y 21218ab3820fSKees Cook ---help--- 2122e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2123e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2124e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2125e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2126e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2127e8581e3dSBaoquan He code internals. 2128e8581e3dSBaoquan He 2129ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2130ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2131ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2132ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2133ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2134ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2135ed9f007eSKees Cook 2136ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2137ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2138ed9f007eSKees Cook 512MB (8 bits of entropy). 21398ab3820fSKees Cook 2140a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2141e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2142e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2143ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2144ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2145ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2146ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2147ed9f007eSKees Cook theoretically possible, but the implementations are further 2148ed9f007eSKees Cook limited due to memory layouts. 2149e8581e3dSBaoquan He 21506807c846SIngo Molnar If unsure, say Y. 2151da2b6fb9SKees Cook 21528ab3820fSKees Cook# Relocation on x86 needs some additional build support 2153845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2154845adf72SH. Peter Anvin def_bool y 21558ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2156845adf72SH. Peter Anvin 2157506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2158a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21598ab3820fSKees Cook default "0x200000" 2160a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2161a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21628f9ca475SIngo Molnar ---help--- 2163506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2164506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2165506f1d07SSam Ravnborg address which meets above alignment restriction. 2166506f1d07SSam Ravnborg 2167506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2168506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2169506f1d07SSam Ravnborg address aligned to above value and run from there. 2170506f1d07SSam Ravnborg 2171506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2172506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2173506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2174506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2175506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2176506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2177506f1d07SSam Ravnborg above alignment restrictions. 2178506f1d07SSam Ravnborg 2179a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2180a0215061SKees Cook this value must be a multiple of 0x200000. 2181a0215061SKees Cook 2182506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2183506f1d07SSam Ravnborg 2184eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT 2185eedb92abSKirill A. Shutemov bool 2186eedb92abSKirill A. Shutemov ---help--- 2187eedb92abSKirill A. Shutemov This option makes base addresses of vmalloc and vmemmap as well as 2188eedb92abSKirill A. Shutemov __PAGE_OFFSET movable during boot. 2189eedb92abSKirill A. Shutemov 21900483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21910483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21920483e1faSThomas Garnier depends on X86_64 21930483e1faSThomas Garnier depends on RANDOMIZE_BASE 2194eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 21950483e1faSThomas Garnier default RANDOMIZE_BASE 21960483e1faSThomas Garnier ---help--- 21970483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21980483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21990483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 22000483e1faSThomas Garnier 22010483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 22020483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 22030483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 22040483e1faSThomas Garnier addresses for each memory section. 22050483e1faSThomas Garnier 22066807c846SIngo Molnar If unsure, say Y. 22070483e1faSThomas Garnier 220890397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 220990397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 221090397a41SThomas Garnier depends on RANDOMIZE_MEMORY 221190397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 221290397a41SThomas Garnier default "0x0" 221390397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 221490397a41SThomas Garnier range 0x0 0x40 221590397a41SThomas Garnier ---help--- 221690397a41SThomas Garnier Define the padding in terabytes added to the existing physical 221790397a41SThomas Garnier memory size during kernel memory randomization. It is useful 221890397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 221990397a41SThomas Garnier address randomization. 222090397a41SThomas Garnier 222190397a41SThomas Garnier If unsure, leave at the default value. 222290397a41SThomas Garnier 2223506f1d07SSam Ravnborgconfig HOTPLUG_CPU 22247c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 222540b31360SStephen Rothwell depends on SMP 2226506f1d07SSam Ravnborg ---help--- 22277c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 22287c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 22297c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 22307c13e6a3SDimitri Sivanich automatically on SMP systems. ) 22317c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2232506f1d07SSam Ravnborg 223380aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 223480aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 223580aa1dffSFenghua Yu default n 22362c922cd0SKees Cook depends on HOTPLUG_CPU 223780aa1dffSFenghua Yu ---help--- 223880aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 223980aa1dffSFenghua Yu 224080aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 224180aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 224280aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 224380aa1dffSFenghua Yu 224480aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 224580aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 224680aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 224780aa1dffSFenghua Yu 224880aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 224980aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 225080aa1dffSFenghua Yu 225180aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 225280aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 225380aa1dffSFenghua Yu be other CPU0 dependencies. 225480aa1dffSFenghua Yu 225580aa1dffSFenghua Yu Please make sure the dependencies are under your control before 225680aa1dffSFenghua Yu you enable this feature. 225780aa1dffSFenghua Yu 225880aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 225980aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 226080aa1dffSFenghua Yu parameter cpu0_hotplug. 226180aa1dffSFenghua Yu 2262a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2263a71c8bc5SFenghua Yu def_bool n 2264a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 22652c922cd0SKees Cook depends on HOTPLUG_CPU 2266a71c8bc5SFenghua Yu ---help--- 2267a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2268a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2269a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2270a71c8bc5SFenghua Yu 2271a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2272a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2273a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2274a71c8bc5SFenghua Yu 2275a71c8bc5SFenghua Yu If unsure, say N. 2276a71c8bc5SFenghua Yu 2277506f1d07SSam Ravnborgconfig COMPAT_VDSO 2278b0b49f26SAndy Lutomirski def_bool n 2279b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2280953fee1dSIngo Molnar depends on COMPAT_32 22818f9ca475SIngo Molnar ---help--- 2282b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2283b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2284b0b49f26SAndy Lutomirski indicated in its segment table. 2285e84446deSRandy Dunlap 2286b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2287b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2288b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2289b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2290b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2291506f1d07SSam Ravnborg 2292b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2293b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2294b0b49f26SAndy Lutomirski 2295b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2296b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2297b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2298b0b49f26SAndy Lutomirski 2299b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2300b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2301506f1d07SSam Ravnborg 23023dc33bd3SKees Cookchoice 23033dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 23043dc33bd3SKees Cook depends on X86_64 23053dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 23063dc33bd3SKees Cook help 23073dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 23083dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 23093dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 23103dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 23113dc33bd3SKees Cook 23123dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 2313076ca272SAndy Lutomirski line parameter vsyscall=[emulate|none]. 23143dc33bd3SKees Cook 23153dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 23163dc33bd3SKees Cook static binaries, you can say None without a performance penalty 23173dc33bd3SKees Cook to improve security. 23183dc33bd3SKees Cook 23193dc33bd3SKees Cook If unsure, select "Emulate". 23203dc33bd3SKees Cook 23213dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 23223dc33bd3SKees Cook bool "Emulate" 23233dc33bd3SKees Cook help 23243dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 23253dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 23263dc33bd3SKees Cook non-executable, but it still contains known contents, 23273dc33bd3SKees Cook which could be used in certain rare security vulnerability 23283dc33bd3SKees Cook exploits. This configuration is recommended when userspace 23293dc33bd3SKees Cook still uses the vsyscall area. 23303dc33bd3SKees Cook 23313dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 23323dc33bd3SKees Cook bool "None" 23333dc33bd3SKees Cook help 23343dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 23353dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 23363dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 23373dc33bd3SKees Cook will be reported to dmesg, so that either old or 23383dc33bd3SKees Cook malicious userspace programs can be identified. 23393dc33bd3SKees Cook 23403dc33bd3SKees Cookendchoice 23413dc33bd3SKees Cook 2342516cbf37STim Birdconfig CMDLINE_BOOL 2343516cbf37STim Bird bool "Built-in kernel command line" 23448f9ca475SIngo Molnar ---help--- 2345516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2346516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2347516cbf37STim Bird necessary or convenient to provide some or all of the 2348516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2349516cbf37STim Bird to not rely on the boot loader to provide them.) 2350516cbf37STim Bird 2351516cbf37STim Bird To compile command line arguments into the kernel, 2352516cbf37STim Bird set this option to 'Y', then fill in the 235369711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2354516cbf37STim Bird 2355516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2356516cbf37STim Bird should leave this option set to 'N'. 2357516cbf37STim Bird 2358516cbf37STim Birdconfig CMDLINE 2359516cbf37STim Bird string "Built-in kernel command string" 2360516cbf37STim Bird depends on CMDLINE_BOOL 2361516cbf37STim Bird default "" 23628f9ca475SIngo Molnar ---help--- 2363516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2364516cbf37STim Bird image and used at boot time. If the boot loader provides a 2365516cbf37STim Bird command line at boot time, it is appended to this string to 2366516cbf37STim Bird form the full kernel command line, when the system boots. 2367516cbf37STim Bird 2368516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2369516cbf37STim Bird change this behavior. 2370516cbf37STim Bird 2371516cbf37STim Bird In most cases, the command line (whether built-in or provided 2372516cbf37STim Bird by the boot loader) should specify the device for the root 2373516cbf37STim Bird file system. 2374516cbf37STim Bird 2375516cbf37STim Birdconfig CMDLINE_OVERRIDE 2376516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2377516cbf37STim Bird depends on CMDLINE_BOOL 23788f9ca475SIngo Molnar ---help--- 2379516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2380516cbf37STim Bird command line, and use ONLY the built-in command line. 2381516cbf37STim Bird 2382516cbf37STim Bird This is used to work around broken boot loaders. This should 2383516cbf37STim Bird be set to 'N' under normal conditions. 2384516cbf37STim Bird 2385a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2386a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2387a5b9e5a2SAndy Lutomirski default y 2388a5b9e5a2SAndy Lutomirski ---help--- 2389a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2390a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2391a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2392a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2393a5b9e5a2SAndy Lutomirski threading libraries. 2394a5b9e5a2SAndy Lutomirski 2395a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2396a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2397a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2398a5b9e5a2SAndy Lutomirski 2399a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2400a5b9e5a2SAndy Lutomirski 2401b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2402b700e7f0SSeth Jennings 2403506f1d07SSam Ravnborgendmenu 2404506f1d07SSam Ravnborg 24053072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 24063072e413SMichal Hocko def_bool y 24073072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 24083072e413SMichal Hocko 2409506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2410506f1d07SSam Ravnborg def_bool y 2411506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2412506f1d07SSam Ravnborg 241335551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 241435551053SGary Hade def_bool y 241535551053SGary Hade depends on MEMORY_HOTPLUG 241635551053SGary Hade 2417e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2418645a7919STejun Heo def_bool y 2419e534c7c5SLee Schermerhorn depends on NUMA 2420e534c7c5SLee Schermerhorn 24219491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 24229491846fSKirill A. Shutemov def_bool y 24239491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 24249491846fSKirill A. Shutemov 2425c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2426c177c81eSNaoya Horiguchi def_bool y 2427c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2428c177c81eSNaoya Horiguchi 24299c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 24309c670ea3SNaoya Horiguchi def_bool y 24319c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 24329c670ea3SNaoya Horiguchi 2433da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2434e279b6c1SSam Ravnborg 2435e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 24363c2362e6SHarvey Harrison def_bool y 2437e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2438e279b6c1SSam Ravnborg 2439e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2440e279b6c1SSam Ravnborg 2441e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2442e279b6c1SSam Ravnborg 2443efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2444efafc8b2SFeng Tang 2445a6b68076SAndi Kleenconfig X86_APM_BOOT 24466fc108a0SJan Beulich def_bool y 2447282e5aabSPaul Bolle depends on APM 2448a6b68076SAndi Kleen 2449e279b6c1SSam Ravnborgmenuconfig APM 2450e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2451efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2452e279b6c1SSam Ravnborg ---help--- 2453e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2454e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2455e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2456e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2457e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2458e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2459e279b6c1SSam Ravnborg 2460e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2461e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2462e279b6c1SSam Ravnborg 2463e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2464e279b6c1SSam Ravnborg machines with more than one CPU. 2465e279b6c1SSam Ravnborg 2466e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 24672dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 24682dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2469e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2470e279b6c1SSam Ravnborg 2471e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2472e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2473e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2474e279b6c1SSam Ravnborg 2475e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2476e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2477e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2478e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2479e279b6c1SSam Ravnborg 2480e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2481e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2482e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2483e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2484e279b6c1SSam Ravnborg APM in your BIOS). 2485e279b6c1SSam Ravnborg 2486e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2487e279b6c1SSam Ravnborg "weird" problems: 2488e279b6c1SSam Ravnborg 2489e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2490e279b6c1SSam Ravnborg enabled. 2491e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2492e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2493e279b6c1SSam Ravnborg the "no387" option to the kernel 2494e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2495e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2496e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2497e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2498e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2499e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2500e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2501e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2502e279b6c1SSam Ravnborg 11) exchange RAM chips 2503e279b6c1SSam Ravnborg 12) exchange the motherboard. 2504e279b6c1SSam Ravnborg 2505e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2506e279b6c1SSam Ravnborg module will be called apm. 2507e279b6c1SSam Ravnborg 2508e279b6c1SSam Ravnborgif APM 2509e279b6c1SSam Ravnborg 2510e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2511e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 25128f9ca475SIngo Molnar ---help--- 2513e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2514e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2515e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2516e279b6c1SSam Ravnborg 2517e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2518e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2519e279b6c1SSam Ravnborg ---help--- 2520e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2521e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2522e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2523e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2524e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2525e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2526e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2527e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2528e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2529e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2530e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2531e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2532e279b6c1SSam Ravnborg this feature. 2533e279b6c1SSam Ravnborg 2534e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2535dd8af076SLen Brown depends on CPU_IDLE 2536e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 25378f9ca475SIngo Molnar ---help--- 2538e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2539e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2540e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2541e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2542e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2543e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2544e279b6c1SSam Ravnborg this option does nothing.) 2545e279b6c1SSam Ravnborg 2546e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2547e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 25488f9ca475SIngo Molnar ---help--- 2549e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2550e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2551e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2552e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2553e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2554e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2555e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2556e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2557e279b6c1SSam Ravnborg especially if you are using gpm. 2558e279b6c1SSam Ravnborg 2559e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2560e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 25618f9ca475SIngo Molnar ---help--- 2562e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2563e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2564e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2565e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2566e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2567e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2568e279b6c1SSam Ravnborg 2569e279b6c1SSam Ravnborgendif # APM 2570e279b6c1SSam Ravnborg 2571bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2572e279b6c1SSam Ravnborg 2573e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2574e279b6c1SSam Ravnborg 257527471fdbSAndy Henroidsource "drivers/idle/Kconfig" 257627471fdbSAndy Henroid 2577e279b6c1SSam Ravnborgendmenu 2578e279b6c1SSam Ravnborg 2579e279b6c1SSam Ravnborg 2580e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2581e279b6c1SSam Ravnborg 2582e279b6c1SSam Ravnborgconfig PCI 25831ac97018SIngo Molnar bool "PCI support" 25841c858087SAdrian Bunk default y 25858f9ca475SIngo Molnar ---help--- 2586e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2587e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2588e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2589e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2590e279b6c1SSam Ravnborg 2591e279b6c1SSam Ravnborgchoice 2592e279b6c1SSam Ravnborg prompt "PCI access mode" 2593efefa6f6SIngo Molnar depends on X86_32 && PCI 2594e279b6c1SSam Ravnborg default PCI_GOANY 2595e279b6c1SSam Ravnborg ---help--- 2596e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2597e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2598e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2599e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2600e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2601e279b6c1SSam Ravnborg 2602e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2603e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2604e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2605e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2606e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2607e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2608e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2609e279b6c1SSam Ravnborg 2610e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2611e279b6c1SSam Ravnborg bool "BIOS" 2612e279b6c1SSam Ravnborg 2613e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2614e279b6c1SSam Ravnborg bool "MMConfig" 2615e279b6c1SSam Ravnborg 2616e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2617e279b6c1SSam Ravnborg bool "Direct" 2618e279b6c1SSam Ravnborg 26193ef0e1f8SAndres Salomonconfig PCI_GOOLPC 262076fb6570SDaniel Drake bool "OLPC XO-1" 26213ef0e1f8SAndres Salomon depends on OLPC 26223ef0e1f8SAndres Salomon 26232bdd1b03SAndres Salomonconfig PCI_GOANY 26242bdd1b03SAndres Salomon bool "Any" 26252bdd1b03SAndres Salomon 2626e279b6c1SSam Ravnborgendchoice 2627e279b6c1SSam Ravnborg 2628e279b6c1SSam Ravnborgconfig PCI_BIOS 26293c2362e6SHarvey Harrison def_bool y 2630efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2631e279b6c1SSam Ravnborg 2632e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2633e279b6c1SSam Ravnborgconfig PCI_DIRECT 26343c2362e6SHarvey Harrison def_bool y 26350aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2636e279b6c1SSam Ravnborg 2637e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2638b45c9f36SJan Kiszka bool "Support mmconfig PCI config space access" if X86_64 2639b45c9f36SJan Kiszka default y 26408364e1f8SJan Kiszka depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST) 2641b45c9f36SJan Kiszka depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) 2642e279b6c1SSam Ravnborg 26433ef0e1f8SAndres Salomonconfig PCI_OLPC 26442bdd1b03SAndres Salomon def_bool y 26452bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 26463ef0e1f8SAndres Salomon 2647b5401a96SAlex Nixonconfig PCI_XEN 2648b5401a96SAlex Nixon def_bool y 2649b5401a96SAlex Nixon depends on PCI && XEN 2650b5401a96SAlex Nixon select SWIOTLB_XEN 2651b5401a96SAlex Nixon 2652e279b6c1SSam Ravnborgconfig PCI_DOMAINS 26533c2362e6SHarvey Harrison def_bool y 2654e279b6c1SSam Ravnborg depends on PCI 2655e279b6c1SSam Ravnborg 26568364e1f8SJan Kiszkaconfig MMCONF_FAM10H 26578364e1f8SJan Kiszka def_bool y 26588364e1f8SJan Kiszka depends on X86_64 && PCI_MMCONFIG && ACPI 2659e279b6c1SSam Ravnborg 26603f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 26616a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 26626ea30386SKees Cook depends on PCI 26633f6ea84aSIra W. Snyder help 26643f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 26653f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 26663f6ea84aSIra W. Snyder not have ACPI. 26673f6ea84aSIra W. Snyder 266864a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 266964a5fed6SBjorn Helgaas is known to be incomplete. 267064a5fed6SBjorn Helgaas 267164a5fed6SBjorn Helgaas You should say N unless you know you need this. 267264a5fed6SBjorn Helgaas 2673e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2674e279b6c1SSam Ravnborg 26753a495511SWilliam Breathitt Grayconfig ISA_BUS 267617a2a129SWilliam Breathitt Gray bool "ISA bus support on modern systems" if EXPERT 26773a495511SWilliam Breathitt Gray help 267817a2a129SWilliam Breathitt Gray Expose ISA bus device drivers and options available for selection and 267917a2a129SWilliam Breathitt Gray configuration. Enable this option if your target machine has an ISA 268017a2a129SWilliam Breathitt Gray bus. ISA is an older system, displaced by PCI and newer bus 268117a2a129SWilliam Breathitt Gray architectures -- if your target machine is modern, it probably does 268217a2a129SWilliam Breathitt Gray not have an ISA bus. 26833a495511SWilliam Breathitt Gray 26843a495511SWilliam Breathitt Gray If unsure, say N. 26853a495511SWilliam Breathitt Gray 26861c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2687e279b6c1SSam Ravnborgconfig ISA_DMA_API 26881c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26891c00f016SDavid Rientjes default y 26901c00f016SDavid Rientjes help 26911c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26921c00f016SDavid Rientjes If unsure, say Y. 2693e279b6c1SSam Ravnborg 269451e68d05SLinus Torvaldsif X86_32 269551e68d05SLinus Torvalds 2696e279b6c1SSam Ravnborgconfig ISA 2697e279b6c1SSam Ravnborg bool "ISA support" 26988f9ca475SIngo Molnar ---help--- 2699e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2700e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2701e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2702e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2703e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2704e279b6c1SSam Ravnborg 2705e279b6c1SSam Ravnborgconfig EISA 2706e279b6c1SSam Ravnborg bool "EISA support" 2707e279b6c1SSam Ravnborg depends on ISA 2708e279b6c1SSam Ravnborg ---help--- 2709e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2710e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2711e279b6c1SSam Ravnborg 2712e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2713e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2714e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2715e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2716e279b6c1SSam Ravnborg 2717e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2718e279b6c1SSam Ravnborg 2719e279b6c1SSam Ravnborg Otherwise, say N. 2720e279b6c1SSam Ravnborg 2721e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2722e279b6c1SSam Ravnborg 2723e279b6c1SSam Ravnborgconfig SCx200 2724e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 27258f9ca475SIngo Molnar ---help--- 2726e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2727e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2728e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2729e279b6c1SSam Ravnborg for other scx200_* drivers. 2730e279b6c1SSam Ravnborg 2731e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2732e279b6c1SSam Ravnborg 2733e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2734e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2735592913ecSJohn Stultz depends on SCx200 2736e279b6c1SSam Ravnborg default y 27378f9ca475SIngo Molnar ---help--- 2738e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2739e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2740e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2741e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2742e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2743e279b6c1SSam Ravnborg 27443ef0e1f8SAndres Salomonconfig OLPC 27453ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 274654008979SThomas Gleixner depends on !X86_PAE 27473c554946SAndres Salomon select GPIOLIB 2748dc3119e7SThomas Gleixner select OF 274945bb1674SDaniel Drake select OF_PROMTREE 2750b4e51854SGrant Likely select IRQ_DOMAIN 27518f9ca475SIngo Molnar ---help--- 27523ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 27533ef0e1f8SAndres Salomon XO hardware. 27543ef0e1f8SAndres Salomon 2755a3128588SDaniel Drakeconfig OLPC_XO1_PM 2756a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 275797c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2758a3128588SDaniel Drake select MFD_CORE 2759bf1ebf00SDaniel Drake ---help--- 276097c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2761bf1ebf00SDaniel Drake 2762cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2763cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2764cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2765cfee9597SDaniel Drake ---help--- 2766cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2767cfee9597SDaniel Drake programmable wakeup source. 2768cfee9597SDaniel Drake 27697feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27707feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 277192e830f2SArnd Bergmann depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2772ed8e47feSRandy Dunlap depends on INPUT=y 2773d8d01a63SDaniel Drake select POWER_SUPPLY 27747feda8e9SDaniel Drake ---help--- 27757feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27767bc74b3dSDaniel Drake - EC-driven system wakeups 27777feda8e9SDaniel Drake - Power button 27787bc74b3dSDaniel Drake - Ebook switch 27792cf2baeaSDaniel Drake - Lid switch 2780e1040ac6SDaniel Drake - AC adapter status updates 2781e1040ac6SDaniel Drake - Battery status updates 27827feda8e9SDaniel Drake 2783a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2784a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2785d8d01a63SDaniel Drake depends on OLPC && ACPI 2786d8d01a63SDaniel Drake select POWER_SUPPLY 2787a0f30f59SDaniel Drake ---help--- 2788a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2789a0f30f59SDaniel Drake - EC-driven system wakeups 2790a0f30f59SDaniel Drake - AC adapter status updates 2791a0f30f59SDaniel Drake - Battery status updates 2792e279b6c1SSam Ravnborg 2793d4f3e350SEd Wildgooseconfig ALIX 2794d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2795d4f3e350SEd Wildgoose select GPIOLIB 2796d4f3e350SEd Wildgoose ---help--- 2797d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2798d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2799d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2800d4f3e350SEd Wildgoose get added here. 2801d4f3e350SEd Wildgoose 2802d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2803d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2804d4f3e350SEd Wildgoose 2805d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2806d4f3e350SEd Wildgoose 2807da4e3302SPhilip Prindevilleconfig NET5501 2808da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2809da4e3302SPhilip Prindeville select GPIOLIB 2810da4e3302SPhilip Prindeville ---help--- 2811da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2812da4e3302SPhilip Prindeville 28133197059aSPhilip A. Prindevilleconfig GEOS 28143197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 28153197059aSPhilip A. Prindeville select GPIOLIB 28163197059aSPhilip A. Prindeville depends on DMI 28173197059aSPhilip A. Prindeville ---help--- 28183197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 28193197059aSPhilip A. Prindeville 28207d029125SVivien Didelotconfig TS5500 28217d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 28227d029125SVivien Didelot depends on MELAN 28237d029125SVivien Didelot select CHECK_SIGNATURE 28247d029125SVivien Didelot select NEW_LEDS 28257d029125SVivien Didelot select LEDS_CLASS 28267d029125SVivien Didelot ---help--- 28277d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 28287d029125SVivien Didelot 2829e279b6c1SSam Ravnborgendif # X86_32 2830e279b6c1SSam Ravnborg 283123ac4ae8SAndreas Herrmannconfig AMD_NB 2832e279b6c1SSam Ravnborg def_bool y 28330e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2834e279b6c1SSam Ravnborg 2835e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2836e279b6c1SSam Ravnborg 2837388b78adSAlexandre Bounineconfig RAPIDIO 2838fdf90abcSAlexandre Bounine tristate "RapidIO support" 2839388b78adSAlexandre Bounine depends on PCI 2840388b78adSAlexandre Bounine default n 2841388b78adSAlexandre Bounine help 2842fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2843388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2844388b78adSAlexandre Bounine 2845388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2846388b78adSAlexandre Bounine 2847e3263ab3SDavid Herrmannconfig X86_SYSFB 2848e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2849e3263ab3SDavid Herrmann help 2850e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2851e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2852e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2853e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2854e3263ab3SDavid Herrmann to x86. 2855e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2856e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2857e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2858e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2859e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2860e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2861e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2862e3263ab3SDavid Herrmann 2863e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2864e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2865e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2866e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2867e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2868e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2869e3263ab3SDavid Herrmann incompatible with simplefb. 2870e3263ab3SDavid Herrmann 2871e3263ab3SDavid Herrmann If unsure, say Y. 2872e3263ab3SDavid Herrmann 2873e279b6c1SSam Ravnborgendmenu 2874e279b6c1SSam Ravnborg 2875e279b6c1SSam Ravnborg 2876e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2877e279b6c1SSam Ravnborg 2878e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2879e279b6c1SSam Ravnborg 2880e279b6c1SSam Ravnborgconfig IA32_EMULATION 2881e279b6c1SSam Ravnborg bool "IA32 Emulation" 2882e279b6c1SSam Ravnborg depends on X86_64 288339f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2884d1603990SRandy Dunlap select BINFMT_ELF 2885a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 288639f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28878f9ca475SIngo Molnar ---help--- 28885fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28895fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28905fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2891e279b6c1SSam Ravnborg 2892e279b6c1SSam Ravnborgconfig IA32_AOUT 2893e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28946b213e1bSDavid Woodhouse depends on IA32_EMULATION 28958f9ca475SIngo Molnar ---help--- 2896e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2897e279b6c1SSam Ravnborg 28980bf62763SH. Peter Anvinconfig X86_X32 28996ea30386SKees Cook bool "x32 ABI for 64-bit mode" 29009b54050bSBrian Gerst depends on X86_64 29015fd92e65SH. J. Lu ---help--- 29025fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 29035fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 29045fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 29055fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 29065fd92e65SH. J. Lu 29075fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 29085fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 29095fd92e65SH. J. Lu option set. 29105fd92e65SH. J. Lu 2911953fee1dSIngo Molnarconfig COMPAT_32 2912953fee1dSIngo Molnar def_bool y 2913953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2914953fee1dSIngo Molnar select HAVE_UID16 2915953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2916953fee1dSIngo Molnar 2917e279b6c1SSam Ravnborgconfig COMPAT 29183c2362e6SHarvey Harrison def_bool y 29190bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2920e279b6c1SSam Ravnborg 29213120e25eSJan Beulichif COMPAT 2922e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 29233120e25eSJan Beulich def_bool y 2924e279b6c1SSam Ravnborg 2925e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 29263c2362e6SHarvey Harrison def_bool y 29273120e25eSJan Beulich depends on SYSVIPC 29283120e25eSJan Beulichendif 2929ee009e4aSDavid Howells 2930e279b6c1SSam Ravnborgendmenu 2931e279b6c1SSam Ravnborg 2932e279b6c1SSam Ravnborg 2933e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2934e5beae16SKeith Packard def_bool y 2935e5beae16SKeith Packard depends on X86_32 2936e5beae16SKeith Packard 29374692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 29384692d77fSAlessandro Rubini bool 293983125a3aSAlessandro Rubini depends on X86_64 || STA2X11 29404692d77fSAlessandro Rubini 2941f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2942f7219a53SAlessandro Rubini bool 294383125a3aSAlessandro Rubini depends on STA2X11 2944f7219a53SAlessandro Rubini 2945e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2946e585513bSKirill A. Shutemov def_bool y 2947e585513bSKirill A. Shutemov 2948e279b6c1SSam Ravnborgsource "net/Kconfig" 2949e279b6c1SSam Ravnborg 2950e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2951e279b6c1SSam Ravnborg 2952e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2953e279b6c1SSam Ravnborg 2954e279b6c1SSam Ravnborgsource "fs/Kconfig" 2955e279b6c1SSam Ravnborg 2956e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2957e279b6c1SSam Ravnborg 2958e279b6c1SSam Ravnborgsource "security/Kconfig" 2959e279b6c1SSam Ravnborg 2960e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2961e279b6c1SSam Ravnborg 2962edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2963edf88417SAvi Kivity 2964e279b6c1SSam Ravnborgsource "lib/Kconfig" 2965