1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 2daa93fabSSam Ravnborg# Select 32 or 64 bit 3daa93fabSSam Ravnborgconfig 64BIT 4104daea1SMasahiro Yamada bool "64-bit kernel" if "$(ARCH)" = "x86" 5104daea1SMasahiro Yamada default "$(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 17117ed454SThomas Gleixner select HAVE_DEBUG_STACKOVERFLOW 18341c787eSIngo Molnar select MODULES_USE_ELF_REL 19341c787eSIngo Molnar select OLD_SIGACTION 20daa93fabSSam Ravnborg 21daa93fabSSam Ravnborgconfig X86_64 223120e25eSJan Beulich def_bool y 233120e25eSJan Beulich depends on 64BIT 24d94e0685SIngo Molnar # Options that are inherently 64-bit kernel only: 254eb0716eSAlexandre Ghiti select ARCH_HAS_GIGANTIC_PAGE 26d94e0685SIngo Molnar select ARCH_SUPPORTS_INT128 27d94e0685SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF 28d94e0685SIngo Molnar select HAVE_ARCH_SOFT_DIRTY 29d94e0685SIngo Molnar select MODULES_USE_ELF_RELA 30f616ab59SChristoph Hellwig select NEED_DMA_MAP_STATE 3109230cbcSChristoph Hellwig select SWIOTLB 32f8781c4aSDominik Brodowski select ARCH_HAS_SYSCALL_WRAPPER 331032c0baSSam Ravnborg 34518049d9SSteven Rostedt (VMware)config FORCE_DYNAMIC_FTRACE 35518049d9SSteven Rostedt (VMware) def_bool y 36518049d9SSteven Rostedt (VMware) depends on X86_32 37518049d9SSteven Rostedt (VMware) depends on FUNCTION_TRACER 38518049d9SSteven Rostedt (VMware) select DYNAMIC_FTRACE 39518049d9SSteven Rostedt (VMware) help 40518049d9SSteven Rostedt (VMware) We keep the static function tracing (!DYNAMIC_FTRACE) around 41518049d9SSteven Rostedt (VMware) in order to test the non static function tracing in the 42518049d9SSteven Rostedt (VMware) generic code, as other architectures still use it. But we 43518049d9SSteven Rostedt (VMware) only need to keep it around for x86_64. No need to keep it 44518049d9SSteven Rostedt (VMware) for x86_32. For x86_32, force DYNAMIC_FTRACE. 45d94e0685SIngo Molnar# 46d94e0685SIngo Molnar# Arch settings 47d94e0685SIngo Molnar# 48d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 49d94e0685SIngo Molnar# ported to 32-bit as well. ) 50d94e0685SIngo Molnar# 518d5fffb9SSam Ravnborgconfig X86 523c2362e6SHarvey Harrison def_bool y 53c763ea26SIngo Molnar # 54c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 55c763ea26SIngo Molnar # 566471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 576e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 58942fa985SYury Norov select ARCH_32BIT_OFF_T if X86_32 596471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 602a21ad57SThomas Gleixner select ARCH_CLOCKSOURCE_INIT 6191dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 62fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 6321266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 646471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 6572d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 66316d097cSDave Hansen select ARCH_HAS_FILTER_PGPROT 676974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 68957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 695c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 7010bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 71c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 723010a5eaSLaurent Dufour select ARCH_HAS_PTE_SPECIAL 7339208aa7SKees Cook select ARCH_HAS_REFCOUNT 740aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 75092b31aaSDan Williams select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE 76d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 77d253ca0cSRick Edgecombe select ARCH_HAS_SET_DIRECT_MAP 78ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 79ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 80ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 81c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 8265f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 836471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 846471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 8577fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 865e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 873599fe12SThomas Gleixner select ARCH_STACKWALK 882c870e61SArnd Bergmann select ARCH_SUPPORTS_ACPI 896471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 906471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 916471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 926471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 936471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 94ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 95c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 9638d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 976471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 986471b825SIngo Molnar select CLKEVT_I8253 996471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 1006471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 1016471b825SIngo Molnar select DCACHE_WORD_ACCESS 10245471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 10345471cd9SLinus Torvalds select EDAC_SUPPORT 1046471b825SIngo Molnar select GENERIC_CLOCKEVENTS 1056471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 1066471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 1076471b825SIngo Molnar select GENERIC_CMOS_UPDATE 1086471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 10961dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 1106471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 1116471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 1126471b825SIngo Molnar select GENERIC_IOMAP 113c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 1140fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 115ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1166471b825SIngo Molnar select GENERIC_IRQ_PROBE 117c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1186471b825SIngo Molnar select GENERIC_IRQ_SHOW 1196471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1206471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1216471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1226471b825SIngo Molnar select GENERIC_STRNLEN_USER 1236471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1247edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1256471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1266471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1276471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1286471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1296471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1306471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 131b34006c4SArd Biesheuvel select HAVE_ARCH_JUMP_LABEL_RELATIVE 132d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1336471b825SIngo Molnar select HAVE_ARCH_KGDB 1349e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1359e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1361b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 137271ca788SArd Biesheuvel select HAVE_ARCH_PREL32_RELOCATIONS 1386471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 139f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 140afaef01cSAlexander Popov select HAVE_ARCH_STACKLEAK 1416471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1426471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 143a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 144e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 145c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1466471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1476471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1486471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 149c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1506471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1516471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1529c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 153677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 15406aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 15503f5781bSWang YanQing select HAVE_EBPF_JIT 15658340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1576630a8e5SChristoph Hellwig select HAVE_EISA 1585f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 159644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1606471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1616471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1626471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1636b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1640067f129SK.Prasad select HAVE_HW_BREAKPOINT 1656471b825SIngo Molnar select HAVE_IDE 1666471b825SIngo Molnar select HAVE_IOREMAP_PROT 1676471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1686471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1696471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1706471b825SIngo Molnar select HAVE_KERNEL_GZIP 1716471b825SIngo Molnar select HAVE_KERNEL_LZ4 1726471b825SIngo Molnar select HAVE_KERNEL_LZMA 1736471b825SIngo Molnar select HAVE_KERNEL_LZO 1746471b825SIngo Molnar select HAVE_KERNEL_XZ 1756471b825SIngo Molnar select HAVE_KPROBES 1766471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 177540adea3SMasami Hiramatsu select HAVE_FUNCTION_ERROR_INJECTION 1786471b825SIngo Molnar select HAVE_KRETPROBES 1796471b825SIngo Molnar select HAVE_KVM 1806471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1816471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1820102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 183ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 1849f132f7eSJoel Fernandes (Google) select HAVE_MOVE_PMD 18542a0bb3fSPetr Mladek select HAVE_NMI 1866471b825SIngo Molnar select HAVE_OPROFILE 1876471b825SIngo Molnar select HAVE_OPTPROBES 1886471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1896471b825SIngo Molnar select HAVE_PERF_EVENTS 190c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 19192e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 192eb01d42aSChristoph Hellwig select HAVE_PCI 193c5e63197SJiri Olsa select HAVE_PERF_REGS 194c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 19548a8b97cSPeter Zijlstra select HAVE_RCU_TABLE_FREE if PARAVIRT 1966471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 1976415b38bSJiri Slaby select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION 1983c88ee19SMasami Hiramatsu select HAVE_FUNCTION_ARG_ACCESS_API 199d148eac0SMasahiro Yamada select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR 200c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 201d6761b8fSMathieu Desnoyers select HAVE_RSEQ 2026471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 2036471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 2047c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 20505736e4aSThomas Gleixner select HOTPLUG_SMT if SMP 206c0185808SThomas Gleixner select IRQ_FORCED_THREADING 20786596f0aSChristoph Hellwig select NEED_SG_DMA_LENGTH 2082eac9c2dSChristoph Hellwig select PCI_DOMAINS if PCI 209625210cfSSinan Kaya select PCI_LOCKLESS_CONFIG if PCI 2106471b825SIngo Molnar select PERF_EVENTS 2113195ef59SPrarit Bhargava select RTC_LIB 212d6faca40SArnd Bergmann select RTC_MC146818_LIB 2136471b825SIngo Molnar select SPARSE_IRQ 21483fe27eaSPranith Kumar select SRCU 2156471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 21615f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 2176471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 2186471b825SIngo Molnar select VIRT_TO_BUS 2196471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 2207d8330a5SBalbir Singh 221ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 2223120e25eSJan Beulich def_bool y 2233120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 224ba7e4d13SIngo Molnar 22551b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 22651b26adaSLinus Torvalds string 22751b26adaSLinus Torvalds default "elf32-i386" if X86_32 22851b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 22951b26adaSLinus Torvalds 23073531905SSam Ravnborgconfig ARCH_DEFCONFIG 231b9b39bfbSSam Ravnborg string 23273531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 23373531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 234b9b39bfbSSam Ravnborg 2358d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2363c2362e6SHarvey Harrison def_bool y 2378d5fffb9SSam Ravnborg 2388d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2393c2362e6SHarvey Harrison def_bool y 2408d5fffb9SSam Ravnborg 2418d5fffb9SSam Ravnborgconfig MMU 2423c2362e6SHarvey Harrison def_bool y 2438d5fffb9SSam Ravnborg 2449e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2459e08f57dSDaniel Cashman default 28 if 64BIT 2469e08f57dSDaniel Cashman default 8 2479e08f57dSDaniel Cashman 2489e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2499e08f57dSDaniel Cashman default 32 if 64BIT 2509e08f57dSDaniel Cashman default 16 2519e08f57dSDaniel Cashman 2529e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2539e08f57dSDaniel Cashman default 8 2549e08f57dSDaniel Cashman 2559e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2569e08f57dSDaniel Cashman default 16 2579e08f57dSDaniel Cashman 2588d5fffb9SSam Ravnborgconfig SBUS 2598d5fffb9SSam Ravnborg bool 2608d5fffb9SSam Ravnborg 2618d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2623120e25eSJan Beulich def_bool y 2633120e25eSJan Beulich depends on ISA_DMA_API 2648d5fffb9SSam Ravnborg 2658d5fffb9SSam Ravnborgconfig GENERIC_BUG 2663c2362e6SHarvey Harrison def_bool y 2678d5fffb9SSam Ravnborg depends on BUG 268b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 269b93a531eSJan Beulich 270b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 271b93a531eSJan Beulich bool 2728d5fffb9SSam Ravnborg 2738d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2743120e25eSJan Beulich def_bool y 2753120e25eSJan Beulich depends on ISA_DMA_API 2768d5fffb9SSam Ravnborg 2771032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2781032c0baSSam Ravnborg def_bool y 2791032c0baSSam Ravnborg 2809a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2819a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2828d5fffb9SSam Ravnborg 2831b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2841b27d05bSPekka Enberg def_bool y 2851b27d05bSPekka Enberg 286316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT 287316d097cSDave Hansen def_bool y 288316d097cSDave Hansen 289dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 29089c9c4c5SBrian Gerst def_bool y 291b32ef636Stravis@sgi.com 29208fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 29308fc4580STejun Heo def_bool y 29408fc4580STejun Heo 29508fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 29611124411STejun Heo def_bool y 29711124411STejun Heo 298801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 299801e4062SJohannes Berg def_bool y 300801e4062SJohannes Berg 301f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 302f4cb5700SJohannes Berg def_bool y 303f4cb5700SJohannes Berg 304cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 305cfe28c5dSSteve Capper def_bool y 306cfe28c5dSSteve Capper 30753313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 30853313b2cSSteve Capper def_bool y 30953313b2cSSteve Capper 3108d5fffb9SSam Ravnborgconfig ZONE_DMA32 311e0fd24a3SJan Beulich def_bool y if X86_64 3128d5fffb9SSam Ravnborg 3138d5fffb9SSam Ravnborgconfig AUDIT_ARCH 314e0fd24a3SJan Beulich def_bool y if X86_64 3158d5fffb9SSam Ravnborg 3166a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3176a11f75bSAkinobu Mita def_bool y 3186a11f75bSAkinobu Mita 319d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 320d6f2d75aSAndrey Ryabinin hex 321d6f2d75aSAndrey Ryabinin depends on KASAN 322d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 323d6f2d75aSAndrey Ryabinin 32469575d38SShane Wangconfig HAVE_INTEL_TXT 32569575d38SShane Wang def_bool y 3266ea30386SKees Cook depends on INTEL_IOMMU && ACPI 32769575d38SShane Wang 3286b0c3d44SSam Ravnborgconfig X86_32_SMP 3296b0c3d44SSam Ravnborg def_bool y 3306b0c3d44SSam Ravnborg depends on X86_32 && SMP 3316b0c3d44SSam Ravnborg 3326b0c3d44SSam Ravnborgconfig X86_64_SMP 3336b0c3d44SSam Ravnborg def_bool y 3346b0c3d44SSam Ravnborg depends on X86_64 && SMP 3356b0c3d44SSam Ravnborg 336ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 337ccbeed3aSTejun Heo def_bool y 3388458f8c2SMasahiro Yamada depends on X86_32 && !STACKPROTECTOR 339ccbeed3aSTejun Heo 3402b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3412b144498SSrikar Dronamraju def_bool y 3422b144498SSrikar Dronamraju 343d20642f0SRob Herringconfig FIX_EARLYCON_MEM 344d20642f0SRob Herring def_bool y 345d20642f0SRob Herring 34694d49eb3SKirill A. Shutemovconfig DYNAMIC_PHYSICAL_MASK 34794d49eb3SKirill A. Shutemov bool 34894d49eb3SKirill A. Shutemov 34998233368SKirill A. Shutemovconfig PGTABLE_LEVELS 35098233368SKirill A. Shutemov int 35177ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 35298233368SKirill A. Shutemov default 4 if X86_64 35398233368SKirill A. Shutemov default 3 if X86_PAE 35498233368SKirill A. Shutemov default 2 35598233368SKirill A. Shutemov 3562a61f474SMasahiro Yamadaconfig CC_HAS_SANE_STACKPROTECTOR 3572a61f474SMasahiro Yamada bool 3582a61f474SMasahiro Yamada default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT 3592a61f474SMasahiro Yamada default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC)) 3602a61f474SMasahiro Yamada help 3612a61f474SMasahiro Yamada We have to make sure stack protector is unconditionally disabled if 3622a61f474SMasahiro Yamada the compiler produces broken code. 3632a61f474SMasahiro Yamada 364506f1d07SSam Ravnborgmenu "Processor type and features" 365506f1d07SSam Ravnborg 3665ee71535SRandy Dunlapconfig ZONE_DMA 3675ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3685ee71535SRandy Dunlap default y 3695ee71535SRandy Dunlap help 3705ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3715ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3725ee71535SRandy Dunlap Disable if no such devices will be used. 3735ee71535SRandy Dunlap 3745ee71535SRandy Dunlap If unsure, say Y. 3755ee71535SRandy Dunlap 376506f1d07SSam Ravnborgconfig SMP 377506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 378506f1d07SSam Ravnborg ---help--- 379506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3804a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3814a474157SRobert Graffham than one CPU, say Y. 382506f1d07SSam Ravnborg 3834a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 384506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 385506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3864a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 387506f1d07SSam Ravnborg will run faster if you say N here. 388506f1d07SSam Ravnborg 389506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 390506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 391506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 392506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 393506f1d07SSam Ravnborg 394506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 395506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 396506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 397506f1d07SSam Ravnborg 398395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 399c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 400506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 401506f1d07SSam Ravnborg 402506f1d07SSam Ravnborg If you don't know what to do here, say N. 403506f1d07SSam Ravnborg 4049def39beSJosh Triplettconfig X86_FEATURE_NAMES 4059def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 4069def39beSJosh Triplett default y 4079def39beSJosh Triplett ---help--- 4089def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 4099def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 4109def39beSJosh Triplett messages. You can disable this to save space, at the expense of 4119def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 4129def39beSJosh Triplett 4139def39beSJosh Triplett If in doubt, say Y. 4149def39beSJosh Triplett 41506cd9a7dSYinghai Luconfig X86_X2APIC 41606cd9a7dSYinghai Lu bool "Support x2apic" 41719e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 41806cd9a7dSYinghai Lu ---help--- 41906cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 42006cd9a7dSYinghai Lu 42106cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 42206cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 42306cd9a7dSYinghai Lu 42406cd9a7dSYinghai Lu If you don't know what to do here, say N. 42506cd9a7dSYinghai Lu 4266695c85bSYinghai Luconfig X86_MPPARSE 4276e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4287a527688SJan Beulich default y 4295ab74722SIngo Molnar depends on X86_LOCAL_APIC 4308f9ca475SIngo Molnar ---help--- 4316695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4326695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4336695c85bSYinghai Lu 434ddd70cf9SJun Nakajimaconfig GOLDFISH 435ddd70cf9SJun Nakajima def_bool y 436ddd70cf9SJun Nakajima depends on X86_GOLDFISH 437ddd70cf9SJun Nakajima 43876b04384SDavid Woodhouseconfig RETPOLINE 43976b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 44076b04384SDavid Woodhouse default y 441d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 44276b04384SDavid Woodhouse help 44376b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 44476b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 44576b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 44676b04384SDavid Woodhouse support for full protection. The kernel may run slower. 44776b04384SDavid Woodhouse 448e6d42931SJohannes Weinerconfig X86_CPU_RESCTRL 449e6d42931SJohannes Weiner bool "x86 CPU resource control support" 4506fe07ce3SBabu Moger depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) 45159fe5a77SThomas Gleixner select KERNFS 45278e99b4aSFenghua Yu help 453e6d42931SJohannes Weiner Enable x86 CPU resource control support. 4546fe07ce3SBabu Moger 4556fe07ce3SBabu Moger Provide support for the allocation and monitoring of system resources 4566fe07ce3SBabu Moger usage by the CPU. 4576fe07ce3SBabu Moger 4586fe07ce3SBabu Moger Intel calls this Intel Resource Director Technology 4596fe07ce3SBabu Moger (Intel(R) RDT). More information about RDT can be found in the 4606fe07ce3SBabu Moger Intel x86 Architecture Software Developer Manual. 4616fe07ce3SBabu Moger 4626fe07ce3SBabu Moger AMD calls this AMD Platform Quality of Service (AMD QoS). 4636fe07ce3SBabu Moger More information about AMD QoS can be found in the AMD64 Technology 4646fe07ce3SBabu Moger Platform Quality of Service Extensions manual. 46578e99b4aSFenghua Yu 46678e99b4aSFenghua Yu Say N if unsure. 46778e99b4aSFenghua Yu 4688425091fSRavikiran G Thirumalaiif X86_32 469a0d0bb4dSRandy Dunlapconfig X86_BIGSMP 470a0d0bb4dSRandy Dunlap bool "Support for big SMP systems with more than 8 CPUs" 471a0d0bb4dSRandy Dunlap depends on SMP 472a0d0bb4dSRandy Dunlap ---help--- 473a0d0bb4dSRandy Dunlap This option is needed for the systems that have more than 8 CPUs 474a0d0bb4dSRandy Dunlap 475c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 476c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 477c5c606d9SRavikiran G Thirumalai default y 4788f9ca475SIngo Molnar ---help--- 47906ac8346SIngo Molnar If you disable this option then the kernel will only support 48006ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 48106ac8346SIngo Molnar systems out there.) 48206ac8346SIngo Molnar 4838425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4848425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 485cb7b8023SBen Hutchings Goldfish (Android emulator) 4868425091fSRavikiran G Thirumalai AMD Elan 4878425091fSRavikiran G Thirumalai RDC R-321x SoC 4888425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 48983125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4903f4110a4SThomas Gleixner Moorestown MID devices 49106ac8346SIngo Molnar 49206ac8346SIngo Molnar If you have one of these systems, or if you want to build a 49306ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4948425091fSRavikiran G Thirumalaiendif 49506ac8346SIngo Molnar 4968425091fSRavikiran G Thirumalaiif X86_64 4978425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4988425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4998425091fSRavikiran G Thirumalai default y 5008425091fSRavikiran G Thirumalai ---help--- 5018425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 5028425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 5038425091fSRavikiran G Thirumalai systems out there.) 5048425091fSRavikiran G Thirumalai 5058425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 5068425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 50744b111b5SSteffen Persvold Numascale NumaChip 5088425091fSRavikiran G Thirumalai ScaleMP vSMP 5098425091fSRavikiran G Thirumalai SGI Ultraviolet 5108425091fSRavikiran G Thirumalai 5118425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 5128425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 5138425091fSRavikiran G Thirumalaiendif 514c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 515c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 51644b111b5SSteffen Persvoldconfig X86_NUMACHIP 51744b111b5SSteffen Persvold bool "Numascale NumaChip" 51844b111b5SSteffen Persvold depends on X86_64 51944b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 52044b111b5SSteffen Persvold depends on NUMA 52144b111b5SSteffen Persvold depends on SMP 52244b111b5SSteffen Persvold depends on X86_X2APIC 523f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 52444b111b5SSteffen Persvold ---help--- 52544b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 52644b111b5SSteffen Persvold enable more than ~168 cores. 52744b111b5SSteffen Persvold If you don't have one of these, you should say N here. 52803b48632SNick Piggin 5296a48565eSIngo Molnarconfig X86_VSMP 530c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5316276a074SBorislav Petkov select HYPERVISOR_GUEST 5326a48565eSIngo Molnar select PARAVIRT 5336a48565eSIngo Molnar depends on X86_64 && PCI 534c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 535ead91d4bSShai Fultheim depends on SMP 5368f9ca475SIngo Molnar ---help--- 5376a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5386a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5396a48565eSIngo Molnar if you have one of these machines. 5406a48565eSIngo Molnar 541c5c606d9SRavikiran G Thirumalaiconfig X86_UV 542c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 543c5c606d9SRavikiran G Thirumalai depends on X86_64 544c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 54554c28d29SJack Steiner depends on NUMA 5461ecb4ae5SAndrew Morton depends on EFI 5479d6c26e7SSuresh Siddha depends on X86_X2APIC 5481222e564SIngo Molnar depends on PCI 549c5c606d9SRavikiran G Thirumalai ---help--- 550c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 551c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 552c5c606d9SRavikiran G Thirumalai 553c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 554c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 555506f1d07SSam Ravnborg 556ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 557ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 558cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 559ddd70cf9SJun Nakajima ---help--- 560ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 561ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 562ddd70cf9SJun Nakajima Goldfish emulator say N here. 563ddd70cf9SJun Nakajima 564c751e17bSThomas Gleixnerconfig X86_INTEL_CE 565c751e17bSThomas Gleixner bool "CE4100 TV platform" 566c751e17bSThomas Gleixner depends on PCI 567c751e17bSThomas Gleixner depends on PCI_GODIRECT 5686084a6e2SJiang Liu depends on X86_IO_APIC 569c751e17bSThomas Gleixner depends on X86_32 570c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 57137bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 572da6b737bSSebastian Andrzej Siewior select OF 573da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 574c751e17bSThomas Gleixner ---help--- 575c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 576c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 577c751e17bSThomas Gleixner boxes and media devices. 578c751e17bSThomas Gleixner 5794cb9b00fSDavid Cohenconfig X86_INTEL_MID 58043605ef1SAlan Cox bool "Intel MID platform support" 58143605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 582edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5831ea7c673SAlan Cox depends on PCI 5843fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5851ea7c673SAlan Cox depends on X86_IO_APIC 5867c9c3a1eSAlan Cox select SFI 5874cb9b00fSDavid Cohen select I2C 5887c9c3a1eSAlan Cox select DW_APB_TIMER 5891ea7c673SAlan Cox select APB_TIMER 5901ea7c673SAlan Cox select INTEL_SCU_IPC 59115a713dfSMika Westerberg select MFD_INTEL_MSIC 5921ea7c673SAlan Cox ---help--- 5934cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5944cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5954cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5961ea7c673SAlan Cox 5974cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5984cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 59943605ef1SAlan Cox 6008bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 6018bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 6028bbc2a13SBryan O'Donoghue depends on X86_32 6038bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 6048bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 6058bbc2a13SBryan O'Donoghue depends on X86_TSC 6068bbc2a13SBryan O'Donoghue depends on PCI 6078bbc2a13SBryan O'Donoghue depends on PCI_GOANY 6088bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 6098bbc2a13SBryan O'Donoghue select IOSF_MBI 6108bbc2a13SBryan O'Donoghue select INTEL_IMR 6119ab6eb51SAndy Shevchenko select COMMON_CLK 6128bbc2a13SBryan O'Donoghue ---help--- 6138bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 6148bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 6158bbc2a13SBryan O'Donoghue compatible Intel Galileo. 6168bbc2a13SBryan O'Donoghue 6173d48aab1SMika Westerbergconfig X86_INTEL_LPSS 6183d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 6195962dd22SSinan Kaya depends on X86 && ACPI && PCI 6203d48aab1SMika Westerberg select COMMON_CLK 6210f531431SMathias Nyman select PINCTRL 622eebb3e8dSAndy Shevchenko select IOSF_MBI 6233d48aab1SMika Westerberg ---help--- 6243d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6253d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6260f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6270f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6283d48aab1SMika Westerberg 62992082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 63092082a88SKen Xue bool "AMD ACPI2Platform devices support" 63192082a88SKen Xue depends on ACPI 63292082a88SKen Xue select COMMON_CLK 63392082a88SKen Xue select PINCTRL 63492082a88SKen Xue ---help--- 63592082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 63692082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 63792082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 63892082a88SKen Xue implemented under PINCTRL subsystem. 63992082a88SKen Xue 640ced3ce76SDavid E. Boxconfig IOSF_MBI 641ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 642ced3ce76SDavid E. Box depends on PCI 643ced3ce76SDavid E. Box ---help--- 644ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 645ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 646ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 647ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 648ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 649ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 650ced3ce76SDavid E. Box This list is not meant to be exclusive. 651ced3ce76SDavid E. Box - BayTrail 652ced3ce76SDavid E. Box - Braswell 653ced3ce76SDavid E. Box - Quark 654ced3ce76SDavid E. Box 655ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 656ced3ce76SDavid E. Box 657ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 658ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 659ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 660ed2226bdSDavid E. Box ---help--- 661ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 662ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 663ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 664ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 665ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 666ed2226bdSDavid E. Box device they want to access. 667ed2226bdSDavid E. Box 668ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 669ed2226bdSDavid E. Box 670c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 671c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 672506f1d07SSam Ravnborg depends on X86_32 673c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 674c5c606d9SRavikiran G Thirumalai select M486 675c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 676c5c606d9SRavikiran G Thirumalai ---help--- 677c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 678c5c606d9SRavikiran G Thirumalai as R-8610-(G). 679c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 680c5c606d9SRavikiran G Thirumalai 681e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6829c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6839c398017SIngo Molnar depends on X86_32 && SMP 684c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6858f9ca475SIngo Molnar ---help--- 686b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 687b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 688b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 689b5660ba7SH. Peter Anvin one and will fallback to default. 690d49c4288SYinghai Lu 691c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 692d49c4288SYinghai Lu 693d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6946fc108a0SJan Beulich def_bool y 695d949f36fSLinus Torvalds # MCE code calls memory_failure(): 696d949f36fSLinus Torvalds depends on X86_MCE 697d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 698d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 699d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 700d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 701d949f36fSLinus Torvalds 70283125a3aSAlessandro Rubiniconfig STA2X11 70383125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 70483125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 705b6e05477SChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 70683125a3aSAlessandro Rubini select SWIOTLB 70783125a3aSAlessandro Rubini select MFD_STA2X11 7080145071bSLinus Walleij select GPIOLIB 70983125a3aSAlessandro Rubini ---help--- 71083125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 71183125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 71283125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 71383125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 71483125a3aSAlessandro Rubini standard PC machines. 71583125a3aSAlessandro Rubini 71682148d1dSShérabconfig X86_32_IRIS 71782148d1dSShérab tristate "Eurobraille/Iris poweroff module" 71882148d1dSShérab depends on X86_32 71982148d1dSShérab ---help--- 72082148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 72182148d1dSShérab to shut themselves down properly. A special I/O sequence is 72282148d1dSShérab needed to do so, which is what this module does at 72382148d1dSShérab kernel shutdown. 72482148d1dSShérab 72582148d1dSShérab This is only for Iris machines from EuroBraille. 72682148d1dSShérab 72782148d1dSShérab If unused, say N. 72882148d1dSShérab 729ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7303c2362e6SHarvey Harrison def_bool y 7313c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 732a87d0914SKen Chen depends on X86 7338f9ca475SIngo Molnar ---help--- 734506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 735506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 736506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 737506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 738506f1d07SSam Ravnborg 739506f1d07SSam Ravnborg If in doubt, say "Y". 740506f1d07SSam Ravnborg 7416276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7426276a074SBorislav Petkov bool "Linux guest support" 7438f9ca475SIngo Molnar ---help--- 7446276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7456276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7466276a074SBorislav Petkov setup. 747506f1d07SSam Ravnborg 7486276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7496276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 750506f1d07SSam Ravnborg 7516276a074SBorislav Petkovif HYPERVISOR_GUEST 752506f1d07SSam Ravnborg 753e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 754e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7558f9ca475SIngo Molnar ---help--- 756e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 757e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 758e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 759e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 760e61bd94aSEduardo Pereira Habkost 761c00a280aSJuergen Grossconfig PARAVIRT_XXL 762c00a280aSJuergen Gross bool 763c00a280aSJuergen Gross 7646276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7656276a074SBorislav Petkov bool "paravirt-ops debugging" 7666276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7676276a074SBorislav Petkov ---help--- 7686276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7696276a074SBorislav Petkov a paravirt_op is missing when it is called. 7706276a074SBorislav Petkov 771b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 772b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7736ea30386SKees Cook depends on PARAVIRT && SMP 774b4ecc126SJeremy Fitzhardinge ---help--- 775b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 776b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 777b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 778b4ecc126SJeremy Fitzhardinge 7794c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7804c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 781b4ecc126SJeremy Fitzhardinge 7824c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 783b4ecc126SJeremy Fitzhardinge 7846276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7856276a074SBorislav Petkov 7866276a074SBorislav Petkovconfig KVM_GUEST 7876276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7886276a074SBorislav Petkov depends on PARAVIRT 7896276a074SBorislav Petkov select PARAVIRT_CLOCK 7906276a074SBorislav Petkov default y 7916276a074SBorislav Petkov ---help--- 7926276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7936276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7946276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7956276a074SBorislav Petkov underlying device model, the host provides the guest with 7966276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7976276a074SBorislav Petkov 7987733607fSMaran Wilsonconfig PVH 7997733607fSMaran Wilson bool "Support for running PVH guests" 8007733607fSMaran Wilson ---help--- 8017733607fSMaran Wilson This option enables the PVH entry point for guest virtual machines 8027733607fSMaran Wilson as specified in the x86/HVM direct boot ABI. 8037733607fSMaran Wilson 8041e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 8051e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 8061e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 8071e20eb85SSrivatsa Vaddagiri ---help--- 8081e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 8091e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 8101e20eb85SSrivatsa Vaddagiri may incur significant overhead. 8111e20eb85SSrivatsa Vaddagiri 8126276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 8136276a074SBorislav Petkov bool "Paravirtual steal time accounting" 8146276a074SBorislav Petkov depends on PARAVIRT 8156276a074SBorislav Petkov ---help--- 8166276a074SBorislav Petkov Select this option to enable fine granularity task steal time 8176276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 8186276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8196276a074SBorislav Petkov that, there can be a small performance impact. 8206276a074SBorislav Petkov 8216276a074SBorislav Petkov If in doubt, say N here. 8226276a074SBorislav Petkov 8237af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8247af192c9SGerd Hoffmann bool 8257af192c9SGerd Hoffmann 8264a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8274a362601SJan Kiszka bool "Jailhouse non-root cell support" 828abde587bSArnd Bergmann depends on X86_64 && PCI 82987e65d05SJan Kiszka select X86_PM_TIMER 8304a362601SJan Kiszka ---help--- 8314a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8324a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8334a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8344a362601SJan Kiszka 8356276a074SBorislav Petkovendif #HYPERVISOR_GUEST 83697349135SJeremy Fitzhardinge 837506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 838506f1d07SSam Ravnborg 839506f1d07SSam Ravnborgconfig HPET_TIMER 8403c2362e6SHarvey Harrison def_bool X86_64 841506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8428f9ca475SIngo Molnar ---help--- 843506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 844506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 845506f1d07SSam Ravnborg present. 846506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 847506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 848506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8494e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8504e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 851506f1d07SSam Ravnborg 852506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 853506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 854506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 855506f1d07SSam Ravnborg 856506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 857506f1d07SSam Ravnborg 858506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8593c2362e6SHarvey Harrison def_bool y 8609d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 861506f1d07SSam Ravnborg 862bb24c471SJacob Panconfig APB_TIMER 863933b9463SAlan Cox def_bool y if X86_INTEL_MID 864933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 86506c3df49SJamie Iles select DW_APB_TIMER 866a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 867bb24c471SJacob Pan help 868bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 869bb24c471SJacob Pan The APBT provides a stable time base on SMP 870bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 871bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 872bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 873bb24c471SJacob Pan 8746a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 875506f1d07SSam Ravnborg# The code disables itself when not needed. 8767ae9392cSThomas Petazzoniconfig DMI 8777ae9392cSThomas Petazzoni default y 878cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8796a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8808f9ca475SIngo Molnar ---help--- 8817ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8827ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8837ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8847ae9392cSThomas Petazzoni BIOS code. 8857ae9392cSThomas Petazzoni 886506f1d07SSam Ravnborgconfig GART_IOMMU 88738901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 888a4ce5a48SChristoph Hellwig select IOMMU_HELPER 889506f1d07SSam Ravnborg select SWIOTLB 89023ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8918f9ca475SIngo Molnar ---help--- 892ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 893ced3c42cSIngo Molnar GART based hardware IOMMUs. 894ced3c42cSIngo Molnar 895ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 896ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 897ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 898ced3c42cSIngo Molnar 899ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 900ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 901ced3c42cSIngo Molnar 902ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 903ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 904ced3c42cSIngo Molnar 32-bit limited device. 905ced3c42cSIngo Molnar 906ced3c42cSIngo Molnar If unsure, say Y. 907506f1d07SSam Ravnborg 908506f1d07SSam Ravnborgconfig CALGARY_IOMMU 909506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 910a4ce5a48SChristoph Hellwig select IOMMU_HELPER 911506f1d07SSam Ravnborg select SWIOTLB 9126ea30386SKees Cook depends on X86_64 && PCI 9138f9ca475SIngo Molnar ---help--- 914506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 915506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 916506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 917506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 918506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 919506f1d07SSam Ravnborg prevents them from going anywhere except their intended 920506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 921506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 922506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 923506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 924506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 925506f1d07SSam Ravnborg If unsure, say Y. 926506f1d07SSam Ravnborg 927506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9283c2362e6SHarvey Harrison def_bool y 9293c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 930506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9318f9ca475SIngo Molnar ---help--- 932506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 933506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 934506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 935506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 936506f1d07SSam Ravnborg If unsure, say Y. 937506f1d07SSam Ravnborg 9381184dc2fSMike Travisconfig MAXSMP 939ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9406ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 94136f5101aSMike Travis select CPUMASK_OFFSTACK 9428f9ca475SIngo Molnar ---help--- 943ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9441184dc2fSMike Travis If unsure, say N. 945506f1d07SSam Ravnborg 946aec6487eSIngo Molnar# 947aec6487eSIngo Molnar# The maximum number of CPUs supported: 948aec6487eSIngo Molnar# 949aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 950aec6487eSIngo Molnar# and which can be configured interactively in the 951aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 952aec6487eSIngo Molnar# 953aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on 954aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel. 955aec6487eSIngo Molnar# 956aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable 957aec6487eSIngo Molnar# interactive configuration. ) 958aec6487eSIngo Molnar# 959a0d0bb4dSRandy Dunlap 960aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN 961a0d0bb4dSRandy Dunlap int 962aec6487eSIngo Molnar default NR_CPUS_RANGE_END if MAXSMP 963a0d0bb4dSRandy Dunlap default 1 if !SMP 964a0d0bb4dSRandy Dunlap default 2 965a0d0bb4dSRandy Dunlap 966aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 967a0d0bb4dSRandy Dunlap int 968a0d0bb4dSRandy Dunlap depends on X86_32 969aec6487eSIngo Molnar default 64 if SMP && X86_BIGSMP 970aec6487eSIngo Molnar default 8 if SMP && !X86_BIGSMP 971a0d0bb4dSRandy Dunlap default 1 if !SMP 972a0d0bb4dSRandy Dunlap 973aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 974a0d0bb4dSRandy Dunlap int 975a0d0bb4dSRandy Dunlap depends on X86_64 976aec6487eSIngo Molnar default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 977aec6487eSIngo Molnar default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 978a0d0bb4dSRandy Dunlap default 1 if !SMP 979aec6487eSIngo Molnar 980aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 981aec6487eSIngo Molnar int 982aec6487eSIngo Molnar depends on X86_32 983aec6487eSIngo Molnar default 32 if X86_BIGSMP 984aec6487eSIngo Molnar default 8 if SMP 985aec6487eSIngo Molnar default 1 if !SMP 986aec6487eSIngo Molnar 987aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 988aec6487eSIngo Molnar int 989aec6487eSIngo Molnar depends on X86_64 990a0d0bb4dSRandy Dunlap default 8192 if MAXSMP 991a0d0bb4dSRandy Dunlap default 64 if SMP 992aec6487eSIngo Molnar default 1 if !SMP 993a0d0bb4dSRandy Dunlap 994506f1d07SSam Ravnborgconfig NR_CPUS 99536f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 996aec6487eSIngo Molnar range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 997aec6487eSIngo Molnar default NR_CPUS_DEFAULT 9988f9ca475SIngo Molnar ---help--- 999506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 1000bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 1001cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 1002506f1d07SSam Ravnborg minimum value which makes sense is 2. 1003506f1d07SSam Ravnborg 1004aec6487eSIngo Molnar This is purely to save memory: each supported CPU adds about 8KB 1005aec6487eSIngo Molnar to the kernel image. 1006506f1d07SSam Ravnborg 1007506f1d07SSam Ravnborgconfig SCHED_SMT 1008dbe73364SThomas Gleixner def_bool y if SMP 1009506f1d07SSam Ravnborg 1010506f1d07SSam Ravnborgconfig SCHED_MC 10113c2362e6SHarvey Harrison def_bool y 10123c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 1013c8e56d20SBorislav Petkov depends on SMP 10148f9ca475SIngo Molnar ---help--- 1015506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 1016506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 1017506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 1018506f1d07SSam Ravnborg 1019de966cf4STim Chenconfig SCHED_MC_PRIO 1020de966cf4STim Chen bool "CPU core priorities scheduler support" 10210a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 10220a21fc12SIngo Molnar select X86_INTEL_PSTATE 10230a21fc12SIngo Molnar select CPU_FREQ 1024de966cf4STim Chen default y 10255e76b2abSTim Chen ---help--- 1026de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1027de966cf4STim Chen core ordering determined at manufacturing time, which allows 1028de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1029de966cf4STim Chen single threaded workloads) than others. 1030de966cf4STim Chen 1031de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1032de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1033de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1034de966cf4STim Chen overall system performance can be achieved. 1035de966cf4STim Chen 1036de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1037de966cf4STim Chen 1038de966cf4STim Chen If unsure say Y here. 10395e76b2abSTim Chen 104030b8b006SThomas Gleixnerconfig UP_LATE_INIT 104130b8b006SThomas Gleixner def_bool y 1042ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 104330b8b006SThomas Gleixner 1044506f1d07SSam Ravnborgconfig X86_UP_APIC 104550849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 104650849eefSJan Beulich default PCI_MSI 104738a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10488f9ca475SIngo Molnar ---help--- 1049506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1050506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1051506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1052506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1053506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1054506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1055506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1056506f1d07SSam Ravnborg lockups. 1057506f1d07SSam Ravnborg 1058506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1059506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1060506f1d07SSam Ravnborg depends on X86_UP_APIC 10618f9ca475SIngo Molnar ---help--- 1062506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1063506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1064506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1065506f1d07SSam Ravnborg 1066506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1067506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1068506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1069506f1d07SSam Ravnborg 1070506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10713c2362e6SHarvey Harrison def_bool y 10720dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1073b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 107452f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1075506f1d07SSam Ravnborg 1076506f1d07SSam Ravnborgconfig X86_IO_APIC 1077b1da1e71SJan Beulich def_bool y 1078b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1079506f1d07SSam Ravnborg 108041b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 108141b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 108241b9eb26SStefan Assmann depends on X86_IO_APIC 10838f9ca475SIngo Molnar ---help--- 108441b9eb26SStefan Assmann This option enables a workaround that fixes a source of 108541b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 108641b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 108741b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 108841b9eb26SStefan Assmann 108941b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 109041b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 109141b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 109241b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 109341b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 109441b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 109541b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 109641b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 109741b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 109841b9eb26SStefan Assmann down (vital) interrupt lines. 109941b9eb26SStefan Assmann 110041b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 110141b9eb26SStefan Assmann increased on these systems. 110241b9eb26SStefan Assmann 1103506f1d07SSam Ravnborgconfig X86_MCE 1104bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1105648ed940SChen, Gong select GENERIC_ALLOCATOR 1106e57dbaf7SBorislav Petkov default y 1107506f1d07SSam Ravnborg ---help--- 1108bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1109bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1110506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1111bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 11124efc0670SAndi Kleen 11135de97c9fSTony Luckconfig X86_MCELOG_LEGACY 11145de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 11155de97c9fSTony Luck depends on X86_MCE 11165de97c9fSTony Luck ---help--- 11175de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 11185de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 11195de97c9fSTony Luck rasdaemon solution. 11205de97c9fSTony Luck 1121506f1d07SSam Ravnborgconfig X86_MCE_INTEL 11223c2362e6SHarvey Harrison def_bool y 11233c2362e6SHarvey Harrison prompt "Intel MCE features" 1124c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 11258f9ca475SIngo Molnar ---help--- 1126506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1127506f1d07SSam Ravnborg the thermal monitor. 1128506f1d07SSam Ravnborg 1129506f1d07SSam Ravnborgconfig X86_MCE_AMD 11303c2362e6SHarvey Harrison def_bool y 11313c2362e6SHarvey Harrison prompt "AMD MCE features" 1132f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11338f9ca475SIngo Molnar ---help--- 1134506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1135506f1d07SSam Ravnborg the DRAM Error Threshold. 1136506f1d07SSam Ravnborg 11374efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11386fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1139c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11404efc0670SAndi Kleen ---help--- 11414efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11425065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11434efc0670SAndi Kleen line. 11444efc0670SAndi Kleen 1145b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1146b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11476fc108a0SJan Beulich def_bool y 1148b2762686SAndi Kleen 1149ea149b36SAndi Kleenconfig X86_MCE_INJECT 1150bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1151ea149b36SAndi Kleen tristate "Machine check injector support" 1152ea149b36SAndi Kleen ---help--- 1153ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1154ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1155ea149b36SAndi Kleen QA it is safe to say n. 1156ea149b36SAndi Kleen 11574efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11584efc0670SAndi Kleen def_bool y 11595bb38adcSAndi Kleen depends on X86_MCE_INTEL 11604efc0670SAndi Kleen 116107dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1162e633c65aSKan Liang 11635aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11641e642812SIngo Molnar bool "Legacy VM86 support" 1165506f1d07SSam Ravnborg depends on X86_32 11668f9ca475SIngo Molnar ---help--- 11675aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11685aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11695aef51c3SAndy Lutomirski 11705aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11715aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11725aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11735aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11745aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11751e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11761e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11771e642812SIngo Molnar mode might be faster than emulation and you might want to 11781e642812SIngo Molnar enable this option. 11795aef51c3SAndy Lutomirski 11801e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11811e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11821e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11831e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11845aef51c3SAndy Lutomirski 11851e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11861e642812SIngo Molnar and slows down exception handling a tiny bit. 11875aef51c3SAndy Lutomirski 11881e642812SIngo Molnar If unsure, say N here. 11895aef51c3SAndy Lutomirski 11905aef51c3SAndy Lutomirskiconfig VM86 11915aef51c3SAndy Lutomirski bool 11925aef51c3SAndy Lutomirski default X86_LEGACY_VM86 119334273f41SH. Peter Anvin 119434273f41SH. Peter Anvinconfig X86_16BIT 119534273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 119634273f41SH. Peter Anvin default y 1197a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 119834273f41SH. Peter Anvin ---help--- 119934273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 120034273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 120134273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 120234273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 120334273f41SH. Peter Anvin 120434273f41SH. Peter Anvinconfig X86_ESPFIX32 120534273f41SH. Peter Anvin def_bool y 120634273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1207506f1d07SSam Ravnborg 1208197725deSH. Peter Anvinconfig X86_ESPFIX64 1209197725deSH. Peter Anvin def_bool y 121034273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1211506f1d07SSam Ravnborg 12121ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 12131ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 12141ad83c85SAndy Lutomirski default y 12151ad83c85SAndy Lutomirski depends on X86_64 12161ad83c85SAndy Lutomirski ---help--- 12171ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 12181ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 12191ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 12201ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 12211ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 12221ad83c85SAndy Lutomirski 0xffffffffff600?00. 12231ad83c85SAndy Lutomirski 12241ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12251ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12261ad83c85SAndy Lutomirski 12271ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12281ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12291ad83c85SAndy Lutomirski 1230506f1d07SSam Ravnborgconfig TOSHIBA 1231506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1232506f1d07SSam Ravnborg depends on X86_32 1233506f1d07SSam Ravnborg ---help--- 1234506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1235506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1236506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1237506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1238506f1d07SSam Ravnborg 1239506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1240506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1241506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1242506f1d07SSam Ravnborg 1243506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1244506f1d07SSam Ravnborg Say N otherwise. 1245506f1d07SSam Ravnborg 1246506f1d07SSam Ravnborgconfig I8K 1247039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1248949a9d70SJean Delvare select HWMON 1249039ae585SPali Rohár select SENSORS_DELL_SMM 1250506f1d07SSam Ravnborg ---help--- 1251039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1252039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1253039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1254039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1255039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1256039ae585SPali Rohár needed userspace package i8kutils. 1257506f1d07SSam Ravnborg 1258039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1259039ae585SPali Rohár use userspace package i8kutils. 1260506f1d07SSam Ravnborg Say N otherwise. 1261506f1d07SSam Ravnborg 1262506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12639ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12649ba16087SJan Beulich depends on X86_32 1265506f1d07SSam Ravnborg ---help--- 1266506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1267506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1268506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1269506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1270506f1d07SSam Ravnborg system. 1271506f1d07SSam Ravnborg 1272506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12735e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1274506f1d07SSam Ravnborg 1275506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1276506f1d07SSam Ravnborg enable this option even if you don't need it. 1277506f1d07SSam Ravnborg Say N otherwise. 1278506f1d07SSam Ravnborg 1279506f1d07SSam Ravnborgconfig MICROCODE 12809a2bc335SBorislav Petkov bool "CPU microcode loading support" 12819a2bc335SBorislav Petkov default y 128280030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1283506f1d07SSam Ravnborg select FW_LOADER 1284506f1d07SSam Ravnborg ---help--- 1285506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12865f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12875f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12885f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12895f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12905f9c01aaSBorislav Petkov the Linux kernel. 1291506f1d07SSam Ravnborg 12925f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12931897a969SJaak Ristioja in Documentation/x86/microcode.txt. For that you need to enable 12945f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12955f9c01aaSBorislav Petkov initrd for microcode blobs. 1296506f1d07SSam Ravnborg 1297c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1298c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1299c508c46eSBenjamin Gilbert config option. 1300506f1d07SSam Ravnborg 13018d86f390SPeter Orubaconfig MICROCODE_INTEL 1302e43f6e67SBorislav Petkov bool "Intel microcode loading support" 13038d86f390SPeter Oruba depends on MICROCODE 13048d86f390SPeter Oruba default MICROCODE 13058d86f390SPeter Oruba select FW_LOADER 13068f9ca475SIngo Molnar ---help--- 13078d86f390SPeter Oruba This options enables microcode patch loading support for Intel 13088d86f390SPeter Oruba processors. 13098d86f390SPeter Oruba 1310b8989db9SAlan For the current Intel microcode data package go to 1311b8989db9SAlan <https://downloadcenter.intel.com> and search for 1312b8989db9SAlan 'Linux Processor Microcode Data File'. 13138d86f390SPeter Oruba 131480cc9f10SPeter Orubaconfig MICROCODE_AMD 1315e43f6e67SBorislav Petkov bool "AMD microcode loading support" 131680cc9f10SPeter Oruba depends on MICROCODE 131780cc9f10SPeter Oruba select FW_LOADER 13188f9ca475SIngo Molnar ---help--- 131980cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 132080cc9f10SPeter Oruba processors will be enabled. 132180cc9f10SPeter Oruba 1322506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 1323c02f48e0SBorislav Petkov bool "Ancient loading interface (DEPRECATED)" 1324c02f48e0SBorislav Petkov default n 1325506f1d07SSam Ravnborg depends on MICROCODE 1326c02f48e0SBorislav Petkov ---help--- 1327c02f48e0SBorislav Petkov DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface 1328c02f48e0SBorislav Petkov which was used by userspace tools like iucode_tool and microcode.ctl. 1329c02f48e0SBorislav Petkov It is inadequate because it runs too late to be able to properly 1330c02f48e0SBorislav Petkov load microcode on a machine and it needs special tools. Instead, you 1331c02f48e0SBorislav Petkov should've switched to the early loading method with the initrd or 1332c02f48e0SBorislav Petkov builtin microcode by now: Documentation/x86/microcode.txt 1333506f1d07SSam Ravnborg 1334506f1d07SSam Ravnborgconfig X86_MSR 1335506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13368f9ca475SIngo Molnar ---help--- 1337506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1338506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1339506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1340506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1341506f1d07SSam Ravnborg systems. 1342506f1d07SSam Ravnborg 1343506f1d07SSam Ravnborgconfig X86_CPUID 1344506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13458f9ca475SIngo Molnar ---help--- 1346506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1347506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1348506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1349506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1350506f1d07SSam Ravnborg 1351506f1d07SSam Ravnborgchoice 1352506f1d07SSam Ravnborg prompt "High Memory Support" 13536fc108a0SJan Beulich default HIGHMEM4G 1354506f1d07SSam Ravnborg depends on X86_32 1355506f1d07SSam Ravnborg 1356506f1d07SSam Ravnborgconfig NOHIGHMEM 1357506f1d07SSam Ravnborg bool "off" 1358506f1d07SSam Ravnborg ---help--- 1359506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1360506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1361506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1362506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1363506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1364506f1d07SSam Ravnborg "high memory". 1365506f1d07SSam Ravnborg 1366506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1367506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1368506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1369506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1370506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1371506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1372506f1d07SSam Ravnborg possible. 1373506f1d07SSam Ravnborg 1374506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1375506f1d07SSam Ravnborg answer "4GB" here. 1376506f1d07SSam Ravnborg 1377506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1378506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1379506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1380506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1381506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1382506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1383506f1d07SSam Ravnborg 1384506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1385506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1386506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1387506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1388506f1d07SSam Ravnborg kernel at boot time.) 1389506f1d07SSam Ravnborg 1390506f1d07SSam Ravnborg If unsure, say "off". 1391506f1d07SSam Ravnborg 1392506f1d07SSam Ravnborgconfig HIGHMEM4G 1393506f1d07SSam Ravnborg bool "4GB" 13948f9ca475SIngo Molnar ---help--- 1395506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1396506f1d07SSam Ravnborg gigabytes of physical RAM. 1397506f1d07SSam Ravnborg 1398506f1d07SSam Ravnborgconfig HIGHMEM64G 1399506f1d07SSam Ravnborg bool "64GB" 140069b8d3fcSMatthew Whitehead depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1401506f1d07SSam Ravnborg select X86_PAE 14028f9ca475SIngo Molnar ---help--- 1403506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1404506f1d07SSam Ravnborg gigabytes of physical RAM. 1405506f1d07SSam Ravnborg 1406506f1d07SSam Ravnborgendchoice 1407506f1d07SSam Ravnborg 1408506f1d07SSam Ravnborgchoice 14096a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1410506f1d07SSam Ravnborg default VMSPLIT_3G 1411506f1d07SSam Ravnborg depends on X86_32 14128f9ca475SIngo Molnar ---help--- 1413506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1414506f1d07SSam Ravnborg 1415506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1416506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1417506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1418506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1419506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1420506f1d07SSam Ravnborg available to user programs, making the address space there 1421506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1422506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1423506f1d07SSam Ravnborg kernel modules. 1424506f1d07SSam Ravnborg 1425506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1426506f1d07SSam Ravnborg option alone! 1427506f1d07SSam Ravnborg 1428506f1d07SSam Ravnborg config VMSPLIT_3G 1429506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1430506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1431506f1d07SSam Ravnborg depends on !X86_PAE 1432506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1433506f1d07SSam Ravnborg config VMSPLIT_2G 1434506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1435506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1436506f1d07SSam Ravnborg depends on !X86_PAE 1437506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1438506f1d07SSam Ravnborg config VMSPLIT_1G 1439506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1440506f1d07SSam Ravnborgendchoice 1441506f1d07SSam Ravnborg 1442506f1d07SSam Ravnborgconfig PAGE_OFFSET 1443506f1d07SSam Ravnborg hex 1444506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1445506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1446506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1447506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1448506f1d07SSam Ravnborg default 0xC0000000 1449506f1d07SSam Ravnborg depends on X86_32 1450506f1d07SSam Ravnborg 1451506f1d07SSam Ravnborgconfig HIGHMEM 14523c2362e6SHarvey Harrison def_bool y 1453506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1454506f1d07SSam Ravnborg 1455506f1d07SSam Ravnborgconfig X86_PAE 14569ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1457506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 1458d4a451d5SChristoph Hellwig select PHYS_ADDR_T_64BIT 14599d99c712SChristian Melki select SWIOTLB 14608f9ca475SIngo Molnar ---help--- 1461506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1462506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1463506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1464506f1d07SSam Ravnborg consumes more pagetable space per process. 1465506f1d07SSam Ravnborg 146677ef56e4SKirill A. Shutemovconfig X86_5LEVEL 146777ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 1468eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 1469162434e7SKirill A. Shutemov select SPARSEMEM_VMEMMAP 147077ef56e4SKirill A. Shutemov depends on X86_64 147177ef56e4SKirill A. Shutemov ---help--- 147277ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 147377ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 147477ef56e4SKirill A. Shutemov physical address space. 147577ef56e4SKirill A. Shutemov 147677ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 147777ef56e4SKirill A. Shutemov 14786657fca0SKirill A. Shutemov A kernel with the option enabled can be booted on machines that 14796657fca0SKirill A. Shutemov support 4- or 5-level paging. 148077ef56e4SKirill A. Shutemov 148177ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 148277ef56e4SKirill A. Shutemov information. 148377ef56e4SKirill A. Shutemov 148477ef56e4SKirill A. Shutemov Say N if unsure. 148577ef56e4SKirill A. Shutemov 148610971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1487e5008abeSLuis R. Rodriguez def_bool y 14884675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 14898f9ca475SIngo Molnar ---help--- 149010971ab2SIngo Molnar Certain kernel features effectively disable kernel 149110971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 149210971ab2SIngo Molnar supports them), so don't confuse the user by printing 149310971ab2SIngo Molnar that we have them enabled. 14949e899816SNick Piggin 14955c280cf6SThomas Gleixnerconfig X86_CPA_STATISTICS 14965c280cf6SThomas Gleixner bool "Enable statistic for Change Page Attribute" 14975c280cf6SThomas Gleixner depends on DEBUG_FS 14985c280cf6SThomas Gleixner ---help--- 14995c280cf6SThomas Gleixner Expose statistics about the Change Page Attribute mechanims, which 1500a943245aSColin Ian King helps to determine the effectiveness of preserving large and huge 15015c280cf6SThomas Gleixner page mappings when mapping protections are changed. 15025c280cf6SThomas Gleixner 15037744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 15047744ccdbSTom Lendacky def_bool y 15057744ccdbSTom Lendacky 15067744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 15077744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 15087744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 150994d49eb3SKirill A. Shutemov select DYNAMIC_PHYSICAL_MASK 1510ce9084baSArd Biesheuvel select ARCH_USE_MEMREMAP_PROT 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 1530506f1d07SSam Ravnborg# Common NUMA Features 1531506f1d07SSam Ravnborgconfig NUMA 1532fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1533506f1d07SSam Ravnborg depends on SMP 1534b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1535b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15368f9ca475SIngo Molnar ---help--- 1537506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1538fd51b2d7SKOSAKI Motohiro 1539506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1540506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1541506f1d07SSam Ravnborg NUMA awareness to the kernel. 1542506f1d07SSam Ravnborg 1543c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1544fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1545fd51b2d7SKOSAKI Motohiro 1546b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15477cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1548fd51b2d7SKOSAKI Motohiro 1549fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1550506f1d07SSam Ravnborg 1551eec1d4faSHans Rosenfeldconfig AMD_NUMA 15523c2362e6SHarvey Harrison def_bool y 15533c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15545da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15558f9ca475SIngo Molnar ---help--- 1556eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1557eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1558eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1559eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1560eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1561506f1d07SSam Ravnborg 1562506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15633c2362e6SHarvey Harrison def_bool y 15643c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1565506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1566506f1d07SSam Ravnborg select ACPI_NUMA 15678f9ca475SIngo Molnar ---help--- 1568506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1569506f1d07SSam Ravnborg 15706ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15716ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15726ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15736ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15746ec6e0d9SSuresh Siddha# for details. 15756ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15766ec6e0d9SSuresh Siddha def_bool y 15776ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15786ec6e0d9SSuresh Siddha 1579506f1d07SSam Ravnborgconfig NUMA_EMU 1580506f1d07SSam Ravnborg bool "NUMA emulation" 15811b7e03efSTejun Heo depends on NUMA 15828f9ca475SIngo Molnar ---help--- 1583506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1584506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1585506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1586506f1d07SSam Ravnborg 1587506f1d07SSam Ravnborgconfig NODES_SHIFT 1588d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 158951591e31SDavid Rientjes range 1 10 159051591e31SDavid Rientjes default "10" if MAXSMP 1591506f1d07SSam Ravnborg default "6" if X86_64 1592506f1d07SSam Ravnborg default "3" 1593506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15948f9ca475SIngo Molnar ---help--- 15951184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1596692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1597506f1d07SSam Ravnborg 1598506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15993c2362e6SHarvey Harrison def_bool y 1600506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1601506f1d07SSam Ravnborg 1602506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1603506f1d07SSam Ravnborg def_bool y 16043b16651fSTejun Heo depends on X86_32 && !NUMA 1605506f1d07SSam Ravnborg 1606506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 16072792107dSMike Rapoport def_bool n 1608b263295dSChristoph Lameter depends on NUMA && X86_32 16092792107dSMike Rapoport depends on BROKEN 1610b263295dSChristoph Lameter 1611506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1612506f1d07SSam Ravnborg def_bool y 16136ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1614506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1615506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1616506f1d07SSam Ravnborg 16173b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 16186ad57f7fSMike Rapoport def_bool X86_64 || (NUMA && X86_32) 16193b16651fSTejun Heo 1620506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1621506f1d07SSam Ravnborg def_bool y 1622b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1623506f1d07SSam Ravnborg 1624506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1625a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16263120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1627a0842b70SToshi Kani help 1628a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1629a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1630a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1631506f1d07SSam Ravnborg 16323b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16333b16651fSTejun Heo def_bool y 16343b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16353b16651fSTejun Heo 1636a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1637a29815a3SAvi Kivity hex 1638a29815a3SAvi Kivity default 0 if X86_32 1639a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1640a29815a3SAvi Kivity 16417a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16427a67832cSDan Williams bool 16437a67832cSDan Williams 1644ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16457a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16469f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16479f53f9faSDan Williams depends on BLK_DEV 16487a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16499f53f9faSDan Williams select LIBNVDIMM 1650ec776ef6SChristoph Hellwig help 1651ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1652ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1653ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1654ec776ef6SChristoph Hellwig they can be used for persistent storage. 1655ec776ef6SChristoph Hellwig 1656ec776ef6SChristoph Hellwig Say Y if unsure. 1657ec776ef6SChristoph Hellwig 1658506f1d07SSam Ravnborgconfig HIGHPTE 1659506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16606fc108a0SJan Beulich depends on HIGHMEM 16618f9ca475SIngo Molnar ---help--- 1662506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1663506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1664506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1665506f1d07SSam Ravnborg entries in high memory. 1666506f1d07SSam Ravnborg 16679f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16689f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16698f9ca475SIngo Molnar ---help--- 16709f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16719f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16729f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16739f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16749f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16759f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16769f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16778c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16789f077871SJeremy Fitzhardinge 16799f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16809f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16819f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16829f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16839f077871SJeremy Fitzhardinge 16849f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16859f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16869f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16879f077871SJeremy Fitzhardinge memory. 16889f077871SJeremy Fitzhardinge 1689c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1690c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1691c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1692c885df50SJeremy Fitzhardinge default y 16938f9ca475SIngo Molnar ---help--- 1694c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1695c885df50SJeremy Fitzhardinge on or off. 1696c885df50SJeremy Fitzhardinge 16979ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1698d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1699d0cd7425SH. Peter Anvin default 64 1700d0cd7425SH. Peter Anvin range 4 640 17018f9ca475SIngo Molnar ---help--- 1702d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1703fc381519SIngo Molnar 1704d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1705d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1706fc381519SIngo Molnar 1707d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1708d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1709d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1710d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1711fc381519SIngo Molnar 1712d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1713d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1714d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1715d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1716d0cd7425SH. Peter Anvin entire low memory range. 1717d0cd7425SH. Peter Anvin 1718d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1719d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1720d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1721d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1722d0cd7425SH. Peter Anvin typical corruption patterns. 1723d0cd7425SH. Peter Anvin 1724d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1725fc381519SIngo Molnar 1726506f1d07SSam Ravnborgconfig MATH_EMULATION 1727506f1d07SSam Ravnborg bool 1728a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1729506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1730506f1d07SSam Ravnborg ---help--- 1731506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1732506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1733506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1734506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1735506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1736506f1d07SSam Ravnborg coprocessor or this emulation. 1737506f1d07SSam Ravnborg 1738506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1739506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1740506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1741506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1742506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1743506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1744506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1745506f1d07SSam Ravnborg intend to use this kernel on different machines. 1746506f1d07SSam Ravnborg 1747506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1748506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1749506f1d07SSam Ravnborg 1750506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1751506f1d07SSam Ravnborg kernel, it won't hurt. 1752506f1d07SSam Ravnborg 1753506f1d07SSam Ravnborgconfig MTRR 17546fc108a0SJan Beulich def_bool y 17556a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1756506f1d07SSam Ravnborg ---help--- 1757506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1758506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1759506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1760506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1761506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1762506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1763506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1764506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1765506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1766506f1d07SSam Ravnborg 1767506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1768506f1d07SSam Ravnborg control registers on other processors can be easily supported 1769506f1d07SSam Ravnborg as well: 1770506f1d07SSam Ravnborg 1771506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1772506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1773506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1774506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1775506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1776506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1777506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1778506f1d07SSam Ravnborg 1779506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1780506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1781506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1782506f1d07SSam Ravnborg 1783506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1784506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1785506f1d07SSam Ravnborg 17867225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1787506f1d07SSam Ravnborg 178895ffa243SYinghai Luconfig MTRR_SANITIZER 17892ffb3501SYinghai Lu def_bool y 179095ffa243SYinghai Lu prompt "MTRR cleanup support" 179195ffa243SYinghai Lu depends on MTRR 17928f9ca475SIngo Molnar ---help--- 1793aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1794aba3728cSThomas Gleixner add writeback entries. 179595ffa243SYinghai Lu 1796aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1797692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1798aba3728cSThomas Gleixner mtrr_chunk_size. 179995ffa243SYinghai Lu 18002ffb3501SYinghai Lu If unsure, say Y. 180195ffa243SYinghai Lu 180295ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1803f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1804f5098d62SYinghai Lu range 0 1 1805f5098d62SYinghai Lu default "0" 180695ffa243SYinghai Lu depends on MTRR_SANITIZER 18078f9ca475SIngo Molnar ---help--- 1808f5098d62SYinghai Lu Enable mtrr cleanup default value 180995ffa243SYinghai Lu 181012031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 181112031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 181212031a62SYinghai Lu range 0 7 181312031a62SYinghai Lu default "1" 181412031a62SYinghai Lu depends on MTRR_SANITIZER 18158f9ca475SIngo Molnar ---help--- 181612031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1817aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 181812031a62SYinghai Lu 18192e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 18206fc108a0SJan Beulich def_bool y 18216a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 18222a8a2719SIngo Molnar depends on MTRR 18238f9ca475SIngo Molnar ---help--- 18242e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1825042b78e4SVenki Pallipadi 18262e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18272e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18282e5d9c85Svenkatesh.pallipadi@intel.com 18292e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1830042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18312e5d9c85Svenkatesh.pallipadi@intel.com 18322e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18332e5d9c85Svenkatesh.pallipadi@intel.com 183446cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 183546cf98cdSVenkatesh Pallipadi def_bool y 183646cf98cdSVenkatesh Pallipadi depends on X86_PAT 183746cf98cdSVenkatesh Pallipadi 1838628c6246SH. Peter Anvinconfig ARCH_RANDOM 1839628c6246SH. Peter Anvin def_bool y 1840628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1841628c6246SH. Peter Anvin ---help--- 1842628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1843628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1844628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1845628c6246SH. Peter Anvin secure hardware random number generator. 1846628c6246SH. Peter Anvin 184751ae4a2dSH. Peter Anvinconfig X86_SMAP 184851ae4a2dSH. Peter Anvin def_bool y 184951ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 185051ae4a2dSH. Peter Anvin ---help--- 185151ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 185251ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 185351ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 185451ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 185551ae4a2dSH. Peter Anvin 185651ae4a2dSH. Peter Anvin If unsure, say Y. 185751ae4a2dSH. Peter Anvin 1858aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1859796ebc81SRicardo Neri def_bool y 1860aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1861aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1862aa35f896SRicardo Neri ---help--- 1863aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1864aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1865796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1866796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1867796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1868796ebc81SRicardo Neri 1869796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1870796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1871796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1872796ebc81SRicardo Neri results are dummy. 1873aa35f896SRicardo Neri 187472e9b5feSDave Hansenconfig X86_INTEL_MPX 187572e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 187672e9b5feSDave Hansen def_bool n 1877df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1878df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1879df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 188072e9b5feSDave Hansen ---help--- 188172e9b5feSDave Hansen MPX provides hardware features that can be used in 188272e9b5feSDave Hansen conjunction with compiler-instrumented code to check 188372e9b5feSDave Hansen memory references. It is designed to detect buffer 188472e9b5feSDave Hansen overflow or underflow bugs. 188572e9b5feSDave Hansen 188672e9b5feSDave Hansen This option enables running applications which are 188772e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 188872e9b5feSDave Hansen itself inside the kernel or to protect the kernel 188972e9b5feSDave Hansen against bad memory references. 189072e9b5feSDave Hansen 189172e9b5feSDave Hansen Enabling this option will make the kernel larger: 189272e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 189372e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 189472e9b5feSDave Hansen will increase the kernel memory overhead of each 189572e9b5feSDave Hansen process and adds some branches to paths used during 189672e9b5feSDave Hansen exec() and munmap(). 189772e9b5feSDave Hansen 189872e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 189972e9b5feSDave Hansen 190072e9b5feSDave Hansen If unsure, say N. 190172e9b5feSDave Hansen 190235e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1903284244a9SDave Hansen prompt "Intel Memory Protection Keys" 190435e97790SDave Hansen def_bool y 1905284244a9SDave Hansen # Note: only available in 64-bit mode 190635e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 190752c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 190852c8e601SIngo Molnar select ARCH_HAS_PKEYS 1909284244a9SDave Hansen ---help--- 1910284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1911284244a9SDave Hansen page-based protections, but without requiring modification of the 1912284244a9SDave Hansen page tables when an application changes protection domains. 1913284244a9SDave Hansen 1914284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1915284244a9SDave Hansen 1916284244a9SDave Hansen If unsure, say y. 191735e97790SDave Hansen 1918506f1d07SSam Ravnborgconfig EFI 19199ba16087SJan Beulich bool "EFI runtime service support" 19205b83683fSHuang, Ying depends on ACPI 1921f6ce5002SSergey Vlasov select UCS2_STRING 1922022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1923506f1d07SSam Ravnborg ---help--- 19248b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1925506f1d07SSam Ravnborg available (such as the EFI variable services). 1926506f1d07SSam Ravnborg 19278b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19288b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19298b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19308b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19318b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19328b2cb7a8SHuang, Ying platforms. 1933506f1d07SSam Ravnborg 1934291f3632SMatt Flemingconfig EFI_STUB 1935291f3632SMatt Fleming bool "EFI stub support" 1936b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19377b2a583aSMatt Fleming select RELOCATABLE 1938291f3632SMatt Fleming ---help--- 1939291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1940291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1941291f3632SMatt Fleming 19424172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19430c759662SMatt Fleming 19447d453eeeSMatt Flemingconfig EFI_MIXED 19457d453eeeSMatt Fleming bool "EFI mixed-mode support" 19467d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19477d453eeeSMatt Fleming ---help--- 19487d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19497d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19507d453eeeSMatt Fleming mode. 19517d453eeeSMatt Fleming 19527d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19537d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19547d453eeeSMatt Fleming the EFI handover protocol must be used. 19557d453eeeSMatt Fleming 19567d453eeeSMatt Fleming If unsure, say N. 19577d453eeeSMatt Fleming 1958506f1d07SSam Ravnborgconfig SECCOMP 19593c2362e6SHarvey Harrison def_bool y 19603c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19618f9ca475SIngo Molnar ---help--- 1962506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1963506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1964506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1965506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1966506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1967506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19689c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1969506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1970506f1d07SSam Ravnborg defined by each seccomp mode. 1971506f1d07SSam Ravnborg 1972506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1973506f1d07SSam Ravnborg 19748636a1f9SMasahiro Yamadasource "kernel/Kconfig.hz" 1975506f1d07SSam Ravnborg 1976506f1d07SSam Ravnborgconfig KEXEC 1977506f1d07SSam Ravnborg bool "kexec system call" 19782965faa5SDave Young select KEXEC_CORE 19798f9ca475SIngo Molnar ---help--- 1980506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1981506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1982506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1983506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1984506f1d07SSam Ravnborg 1985506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1986506f1d07SSam Ravnborg 1987506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1988506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1989bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1990bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1991bf220695SGeert Uytterhoeven made. 1992506f1d07SSam Ravnborg 199374ca317cSVivek Goyalconfig KEXEC_FILE 199474ca317cSVivek Goyal bool "kexec file based system call" 19952965faa5SDave Young select KEXEC_CORE 199674ca317cSVivek Goyal select BUILD_BIN2C 199774ca317cSVivek Goyal depends on X86_64 199874ca317cSVivek Goyal depends on CRYPTO=y 199974ca317cSVivek Goyal depends on CRYPTO_SHA256=y 200074ca317cSVivek Goyal ---help--- 200174ca317cSVivek Goyal This is new version of kexec system call. This system call is 200274ca317cSVivek Goyal file based and takes file descriptors as system call argument 200374ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 200474ca317cSVivek Goyal accepted by previous system call. 200574ca317cSVivek Goyal 2006b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY 2007b799a09fSAKASHI Takahiro def_bool KEXEC_FILE 2008b799a09fSAKASHI Takahiro 20098e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 20108e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 201174ca317cSVivek Goyal depends on KEXEC_FILE 20128e7d8381SVivek Goyal ---help--- 20138e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 2014d8eb8940SBorislav Petkov the kexec_file_load() syscall. 20158e7d8381SVivek Goyal 2016d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 2017d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 2018d8eb8940SBorislav Petkov loaded in order for this to work. 20198e7d8381SVivek Goyal 20208e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 20218e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 20228e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 20238e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 20248e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 20258e7d8381SVivek Goyal ---help--- 20268e7d8381SVivek Goyal Enable bzImage signature verification support. 20278e7d8381SVivek Goyal 2028506f1d07SSam Ravnborgconfig CRASH_DUMP 202904b69447SPavel Machek bool "kernel crash dumps" 2030506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20318f9ca475SIngo Molnar ---help--- 2032506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2033506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2034506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2035506f1d07SSam Ravnborg a specially reserved region and then later executed after 2036506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2037506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2038506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2039506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2040506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2041506f1d07SSam Ravnborg 20423ab83521SHuang Yingconfig KEXEC_JUMP 20436ea30386SKees Cook bool "kexec jump" 2044fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20458f9ca475SIngo Molnar ---help--- 204689081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 204789081d17SHuang Ying code in physical address mode via KEXEC 20483ab83521SHuang Ying 2049506f1d07SSam Ravnborgconfig PHYSICAL_START 20506a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2051ceefccc9SH. Peter Anvin default "0x1000000" 20528f9ca475SIngo Molnar ---help--- 2053506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2054506f1d07SSam Ravnborg 2055506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2056506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2057506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2058506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2059506f1d07SSam Ravnborg address. 2060506f1d07SSam Ravnborg 2061506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2062506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2063506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2064506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2065506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2066506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2067506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2068506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2069506f1d07SSam Ravnborg 2070ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2071ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2072ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2073ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2074ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2075ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2076ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2077ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2078ceefccc9SH. Peter Anvin for more details about crash dumps. 2079506f1d07SSam Ravnborg 2080506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2081506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2082506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2083506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2084506f1d07SSam Ravnborg is present because there are users out there who continue to use 2085506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2086506f1d07SSam Ravnborg line. 2087506f1d07SSam Ravnborg 2088506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2089506f1d07SSam Ravnborg 2090506f1d07SSam Ravnborgconfig RELOCATABLE 209126717808SH. Peter Anvin bool "Build a relocatable kernel" 209226717808SH. Peter Anvin default y 20938f9ca475SIngo Molnar ---help--- 2094506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2095506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2096506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2097506f1d07SSam Ravnborg but are discarded at runtime. 2098506f1d07SSam Ravnborg 2099506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2100506f1d07SSam Ravnborg must live at a different physical address than the primary 2101506f1d07SSam Ravnborg kernel. 2102506f1d07SSam Ravnborg 2103506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2104506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 21058ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2106506f1d07SSam Ravnborg 21078ab3820fSKees Cookconfig RANDOMIZE_BASE 2108e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 21098ab3820fSKees Cook depends on RELOCATABLE 21106807c846SIngo Molnar default y 21118ab3820fSKees Cook ---help--- 2112e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2113e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2114e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2115e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2116e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2117e8581e3dSBaoquan He code internals. 2118e8581e3dSBaoquan He 2119ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2120ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2121ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2122ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2123ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2124ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2125ed9f007eSKees Cook 2126ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2127ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2128ed9f007eSKees Cook 512MB (8 bits of entropy). 21298ab3820fSKees Cook 2130a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2131e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2132e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2133ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2134ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2135ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2136ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2137ed9f007eSKees Cook theoretically possible, but the implementations are further 2138ed9f007eSKees Cook limited due to memory layouts. 2139e8581e3dSBaoquan He 21406807c846SIngo Molnar If unsure, say Y. 2141da2b6fb9SKees Cook 21428ab3820fSKees Cook# Relocation on x86 needs some additional build support 2143845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2144845adf72SH. Peter Anvin def_bool y 21458ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2146845adf72SH. Peter Anvin 2147506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2148a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21498ab3820fSKees Cook default "0x200000" 2150a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2151a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21528f9ca475SIngo Molnar ---help--- 2153506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2154506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2155506f1d07SSam Ravnborg address which meets above alignment restriction. 2156506f1d07SSam Ravnborg 2157506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2158506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2159506f1d07SSam Ravnborg address aligned to above value and run from there. 2160506f1d07SSam Ravnborg 2161506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2162506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2163506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2164506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2165506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2166506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2167506f1d07SSam Ravnborg above alignment restrictions. 2168506f1d07SSam Ravnborg 2169a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2170a0215061SKees Cook this value must be a multiple of 0x200000. 2171a0215061SKees Cook 2172506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2173506f1d07SSam Ravnborg 2174eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT 2175eedb92abSKirill A. Shutemov bool 2176eedb92abSKirill A. Shutemov ---help--- 2177eedb92abSKirill A. Shutemov This option makes base addresses of vmalloc and vmemmap as well as 2178eedb92abSKirill A. Shutemov __PAGE_OFFSET movable during boot. 2179eedb92abSKirill A. Shutemov 21800483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21810483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21820483e1faSThomas Garnier depends on X86_64 21830483e1faSThomas Garnier depends on RANDOMIZE_BASE 2184eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 21850483e1faSThomas Garnier default RANDOMIZE_BASE 21860483e1faSThomas Garnier ---help--- 21870483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21880483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21890483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21900483e1faSThomas Garnier 21910483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21920483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21930483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21940483e1faSThomas Garnier addresses for each memory section. 21950483e1faSThomas Garnier 21966807c846SIngo Molnar If unsure, say Y. 21970483e1faSThomas Garnier 219890397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 219990397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 220090397a41SThomas Garnier depends on RANDOMIZE_MEMORY 220190397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 220290397a41SThomas Garnier default "0x0" 220390397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 220490397a41SThomas Garnier range 0x0 0x40 220590397a41SThomas Garnier ---help--- 220690397a41SThomas Garnier Define the padding in terabytes added to the existing physical 220790397a41SThomas Garnier memory size during kernel memory randomization. It is useful 220890397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 220990397a41SThomas Garnier address randomization. 221090397a41SThomas Garnier 221190397a41SThomas Garnier If unsure, leave at the default value. 221290397a41SThomas Garnier 2213506f1d07SSam Ravnborgconfig HOTPLUG_CPU 2214bebd024eSThomas Gleixner def_bool y 221540b31360SStephen Rothwell depends on SMP 2216506f1d07SSam Ravnborg 221780aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 221880aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 22192c922cd0SKees Cook depends on HOTPLUG_CPU 222080aa1dffSFenghua Yu ---help--- 222180aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 222280aa1dffSFenghua Yu 222380aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 222480aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 222580aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 222680aa1dffSFenghua Yu 222780aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 222880aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 222980aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 223080aa1dffSFenghua Yu 223180aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 223280aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 223380aa1dffSFenghua Yu 223480aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 223580aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 223680aa1dffSFenghua Yu be other CPU0 dependencies. 223780aa1dffSFenghua Yu 223880aa1dffSFenghua Yu Please make sure the dependencies are under your control before 223980aa1dffSFenghua Yu you enable this feature. 224080aa1dffSFenghua Yu 224180aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 224280aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 224380aa1dffSFenghua Yu parameter cpu0_hotplug. 224480aa1dffSFenghua Yu 2245a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2246a71c8bc5SFenghua Yu def_bool n 2247a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 22482c922cd0SKees Cook depends on HOTPLUG_CPU 2249a71c8bc5SFenghua Yu ---help--- 2250a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2251a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2252a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2253a71c8bc5SFenghua Yu 2254a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2255a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2256a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2257a71c8bc5SFenghua Yu 2258a71c8bc5SFenghua Yu If unsure, say N. 2259a71c8bc5SFenghua Yu 2260506f1d07SSam Ravnborgconfig COMPAT_VDSO 2261b0b49f26SAndy Lutomirski def_bool n 2262b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2263953fee1dSIngo Molnar depends on COMPAT_32 22648f9ca475SIngo Molnar ---help--- 2265b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2266b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2267b0b49f26SAndy Lutomirski indicated in its segment table. 2268e84446deSRandy Dunlap 2269b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2270b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2271b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2272b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2273b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2274506f1d07SSam Ravnborg 2275b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2276b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2277b0b49f26SAndy Lutomirski 2278b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2279b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2280b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2281b0b49f26SAndy Lutomirski 2282b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2283b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2284506f1d07SSam Ravnborg 22853dc33bd3SKees Cookchoice 22863dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22873dc33bd3SKees Cook depends on X86_64 2288*625b7b7fSAndy Lutomirski default LEGACY_VSYSCALL_XONLY 22893dc33bd3SKees Cook help 22903dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 22913dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 22923dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 22933dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22943dc33bd3SKees Cook 22953dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 2296bd49e16eSAndy Lutomirski line parameter vsyscall=[emulate|xonly|none]. 22973dc33bd3SKees Cook 22983dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22993dc33bd3SKees Cook static binaries, you can say None without a performance penalty 23003dc33bd3SKees Cook to improve security. 23013dc33bd3SKees Cook 2302bd49e16eSAndy Lutomirski If unsure, select "Emulate execution only". 23033dc33bd3SKees Cook 23043dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 2305bd49e16eSAndy Lutomirski bool "Full emulation" 23063dc33bd3SKees Cook help 2307bd49e16eSAndy Lutomirski The kernel traps and emulates calls into the fixed vsyscall 2308bd49e16eSAndy Lutomirski address mapping. This makes the mapping non-executable, but 2309bd49e16eSAndy Lutomirski it still contains readable known contents, which could be 2310bd49e16eSAndy Lutomirski used in certain rare security vulnerability exploits. This 2311bd49e16eSAndy Lutomirski configuration is recommended when using legacy userspace 2312bd49e16eSAndy Lutomirski that still uses vsyscalls along with legacy binary 2313bd49e16eSAndy Lutomirski instrumentation tools that require code to be readable. 2314bd49e16eSAndy Lutomirski 2315bd49e16eSAndy Lutomirski An example of this type of legacy userspace is running 2316bd49e16eSAndy Lutomirski Pin on an old binary that still uses vsyscalls. 2317bd49e16eSAndy Lutomirski 2318bd49e16eSAndy Lutomirski config LEGACY_VSYSCALL_XONLY 2319bd49e16eSAndy Lutomirski bool "Emulate execution only" 2320bd49e16eSAndy Lutomirski help 2321bd49e16eSAndy Lutomirski The kernel traps and emulates calls into the fixed vsyscall 2322bd49e16eSAndy Lutomirski address mapping and does not allow reads. This 2323bd49e16eSAndy Lutomirski configuration is recommended when userspace might use the 2324bd49e16eSAndy Lutomirski legacy vsyscall area but support for legacy binary 2325bd49e16eSAndy Lutomirski instrumentation of legacy code is not needed. It mitigates 2326bd49e16eSAndy Lutomirski certain uses of the vsyscall area as an ASLR-bypassing 2327bd49e16eSAndy Lutomirski buffer. 23283dc33bd3SKees Cook 23293dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 23303dc33bd3SKees Cook bool "None" 23313dc33bd3SKees Cook help 23323dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 23333dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 23343dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 23353dc33bd3SKees Cook will be reported to dmesg, so that either old or 23363dc33bd3SKees Cook malicious userspace programs can be identified. 23373dc33bd3SKees Cook 23383dc33bd3SKees Cookendchoice 23393dc33bd3SKees Cook 2340516cbf37STim Birdconfig CMDLINE_BOOL 2341516cbf37STim Bird bool "Built-in kernel command line" 23428f9ca475SIngo Molnar ---help--- 2343516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2344516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2345516cbf37STim Bird necessary or convenient to provide some or all of the 2346516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2347516cbf37STim Bird to not rely on the boot loader to provide them.) 2348516cbf37STim Bird 2349516cbf37STim Bird To compile command line arguments into the kernel, 2350516cbf37STim Bird set this option to 'Y', then fill in the 235169711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2352516cbf37STim Bird 2353516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2354516cbf37STim Bird should leave this option set to 'N'. 2355516cbf37STim Bird 2356516cbf37STim Birdconfig CMDLINE 2357516cbf37STim Bird string "Built-in kernel command string" 2358516cbf37STim Bird depends on CMDLINE_BOOL 2359516cbf37STim Bird default "" 23608f9ca475SIngo Molnar ---help--- 2361516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2362516cbf37STim Bird image and used at boot time. If the boot loader provides a 2363516cbf37STim Bird command line at boot time, it is appended to this string to 2364516cbf37STim Bird form the full kernel command line, when the system boots. 2365516cbf37STim Bird 2366516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2367516cbf37STim Bird change this behavior. 2368516cbf37STim Bird 2369516cbf37STim Bird In most cases, the command line (whether built-in or provided 2370516cbf37STim Bird by the boot loader) should specify the device for the root 2371516cbf37STim Bird file system. 2372516cbf37STim Bird 2373516cbf37STim Birdconfig CMDLINE_OVERRIDE 2374516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2375516cbf37STim Bird depends on CMDLINE_BOOL 23768f9ca475SIngo Molnar ---help--- 2377516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2378516cbf37STim Bird command line, and use ONLY the built-in command line. 2379516cbf37STim Bird 2380516cbf37STim Bird This is used to work around broken boot loaders. This should 2381516cbf37STim Bird be set to 'N' under normal conditions. 2382516cbf37STim Bird 2383a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2384a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2385a5b9e5a2SAndy Lutomirski default y 2386a5b9e5a2SAndy Lutomirski ---help--- 2387a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2388a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2389a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2390a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2391a5b9e5a2SAndy Lutomirski threading libraries. 2392a5b9e5a2SAndy Lutomirski 2393a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2394a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2395a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2396a5b9e5a2SAndy Lutomirski 2397a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2398a5b9e5a2SAndy Lutomirski 2399b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2400b700e7f0SSeth Jennings 2401506f1d07SSam Ravnborgendmenu 2402506f1d07SSam Ravnborg 24033072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 24043072e413SMichal Hocko def_bool y 24053072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 24063072e413SMichal Hocko 2407506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2408506f1d07SSam Ravnborg def_bool y 2409506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2410506f1d07SSam Ravnborg 241135551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 241235551053SGary Hade def_bool y 241335551053SGary Hade depends on MEMORY_HOTPLUG 241435551053SGary Hade 2415e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2416645a7919STejun Heo def_bool y 2417e534c7c5SLee Schermerhorn depends on NUMA 2418e534c7c5SLee Schermerhorn 24199491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 24209491846fSKirill A. Shutemov def_bool y 24219491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 24229491846fSKirill A. Shutemov 2423c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2424c177c81eSNaoya Horiguchi def_bool y 2425c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2426c177c81eSNaoya Horiguchi 24279c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 24289c670ea3SNaoya Horiguchi def_bool y 24299c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 24309c670ea3SNaoya Horiguchi 2431da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2432e279b6c1SSam Ravnborg 2433e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 24343c2362e6SHarvey Harrison def_bool y 243544556530SZhimin Gu depends on HIBERNATION 2436e279b6c1SSam Ravnborg 2437e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2438e279b6c1SSam Ravnborg 2439e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2440e279b6c1SSam Ravnborg 2441efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2442efafc8b2SFeng Tang 2443a6b68076SAndi Kleenconfig X86_APM_BOOT 24446fc108a0SJan Beulich def_bool y 2445282e5aabSPaul Bolle depends on APM 2446a6b68076SAndi Kleen 2447e279b6c1SSam Ravnborgmenuconfig APM 2448e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2449efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2450e279b6c1SSam Ravnborg ---help--- 2451e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2452e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2453e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2454e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2455e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2456e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2457e279b6c1SSam Ravnborg 2458e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2459e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2460e279b6c1SSam Ravnborg 2461e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2462e279b6c1SSam Ravnborg machines with more than one CPU. 2463e279b6c1SSam Ravnborg 2464e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 24652dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 24662dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2467e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2468e279b6c1SSam Ravnborg 2469e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2470e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2471e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2472e279b6c1SSam Ravnborg 2473e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2474e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2475e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2476e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2477e279b6c1SSam Ravnborg 2478e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2479e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2480e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2481e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2482e279b6c1SSam Ravnborg APM in your BIOS). 2483e279b6c1SSam Ravnborg 2484e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2485e279b6c1SSam Ravnborg "weird" problems: 2486e279b6c1SSam Ravnborg 2487e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2488e279b6c1SSam Ravnborg enabled. 2489e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2490e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2491e279b6c1SSam Ravnborg the "no387" option to the kernel 2492e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2493e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2494e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2495e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2496e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2497e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2498e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2499e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2500e279b6c1SSam Ravnborg 11) exchange RAM chips 2501e279b6c1SSam Ravnborg 12) exchange the motherboard. 2502e279b6c1SSam Ravnborg 2503e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2504e279b6c1SSam Ravnborg module will be called apm. 2505e279b6c1SSam Ravnborg 2506e279b6c1SSam Ravnborgif APM 2507e279b6c1SSam Ravnborg 2508e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2509e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 25108f9ca475SIngo Molnar ---help--- 2511e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2512e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2513e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2514e279b6c1SSam Ravnborg 2515e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2516e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2517e279b6c1SSam Ravnborg ---help--- 2518e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2519e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2520e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2521e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2522e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2523e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2524e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2525e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2526e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2527e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2528e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2529e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2530e279b6c1SSam Ravnborg this feature. 2531e279b6c1SSam Ravnborg 2532e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2533dd8af076SLen Brown depends on CPU_IDLE 2534e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 25358f9ca475SIngo Molnar ---help--- 2536e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2537e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2538e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2539e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2540e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2541e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2542e279b6c1SSam Ravnborg this option does nothing.) 2543e279b6c1SSam Ravnborg 2544e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2545e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 25468f9ca475SIngo Molnar ---help--- 2547e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2548e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2549e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2550e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2551e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2552e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2553e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2554e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2555e279b6c1SSam Ravnborg especially if you are using gpm. 2556e279b6c1SSam Ravnborg 2557e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2558e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 25598f9ca475SIngo Molnar ---help--- 2560e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2561e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2562e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2563e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2564e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2565e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2566e279b6c1SSam Ravnborg 2567e279b6c1SSam Ravnborgendif # APM 2568e279b6c1SSam Ravnborg 2569bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2570e279b6c1SSam Ravnborg 2571e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2572e279b6c1SSam Ravnborg 257327471fdbSAndy Henroidsource "drivers/idle/Kconfig" 257427471fdbSAndy Henroid 2575e279b6c1SSam Ravnborgendmenu 2576e279b6c1SSam Ravnborg 2577e279b6c1SSam Ravnborg 2578e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2579e279b6c1SSam Ravnborg 2580e279b6c1SSam Ravnborgchoice 2581e279b6c1SSam Ravnborg prompt "PCI access mode" 2582efefa6f6SIngo Molnar depends on X86_32 && PCI 2583e279b6c1SSam Ravnborg default PCI_GOANY 2584e279b6c1SSam Ravnborg ---help--- 2585e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2586e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2587e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2588e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2589e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2590e279b6c1SSam Ravnborg 2591e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2592e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2593e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2594e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2595e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2596e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2597e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2598e279b6c1SSam Ravnborg 2599e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2600e279b6c1SSam Ravnborg bool "BIOS" 2601e279b6c1SSam Ravnborg 2602e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2603e279b6c1SSam Ravnborg bool "MMConfig" 2604e279b6c1SSam Ravnborg 2605e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2606e279b6c1SSam Ravnborg bool "Direct" 2607e279b6c1SSam Ravnborg 26083ef0e1f8SAndres Salomonconfig PCI_GOOLPC 260976fb6570SDaniel Drake bool "OLPC XO-1" 26103ef0e1f8SAndres Salomon depends on OLPC 26113ef0e1f8SAndres Salomon 26122bdd1b03SAndres Salomonconfig PCI_GOANY 26132bdd1b03SAndres Salomon bool "Any" 26142bdd1b03SAndres Salomon 2615e279b6c1SSam Ravnborgendchoice 2616e279b6c1SSam Ravnborg 2617e279b6c1SSam Ravnborgconfig PCI_BIOS 26183c2362e6SHarvey Harrison def_bool y 2619efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2620e279b6c1SSam Ravnborg 2621e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2622e279b6c1SSam Ravnborgconfig PCI_DIRECT 26233c2362e6SHarvey Harrison def_bool y 26240aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2625e279b6c1SSam Ravnborg 2626e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2627b45c9f36SJan Kiszka bool "Support mmconfig PCI config space access" if X86_64 2628b45c9f36SJan Kiszka default y 26298364e1f8SJan Kiszka depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST) 2630b45c9f36SJan Kiszka depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) 2631e279b6c1SSam Ravnborg 26323ef0e1f8SAndres Salomonconfig PCI_OLPC 26332bdd1b03SAndres Salomon def_bool y 26342bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 26353ef0e1f8SAndres Salomon 2636b5401a96SAlex Nixonconfig PCI_XEN 2637b5401a96SAlex Nixon def_bool y 2638b5401a96SAlex Nixon depends on PCI && XEN 2639b5401a96SAlex Nixon select SWIOTLB_XEN 2640b5401a96SAlex Nixon 26418364e1f8SJan Kiszkaconfig MMCONF_FAM10H 26428364e1f8SJan Kiszka def_bool y 26438364e1f8SJan Kiszka depends on X86_64 && PCI_MMCONFIG && ACPI 2644e279b6c1SSam Ravnborg 26453f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 26466a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 26476ea30386SKees Cook depends on PCI 26483f6ea84aSIra W. Snyder help 26493f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 26503f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 26513f6ea84aSIra W. Snyder not have ACPI. 26523f6ea84aSIra W. Snyder 265364a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 265464a5fed6SBjorn Helgaas is known to be incomplete. 265564a5fed6SBjorn Helgaas 265664a5fed6SBjorn Helgaas You should say N unless you know you need this. 265764a5fed6SBjorn Helgaas 26583a495511SWilliam Breathitt Grayconfig ISA_BUS 265917a2a129SWilliam Breathitt Gray bool "ISA bus support on modern systems" if EXPERT 26603a495511SWilliam Breathitt Gray help 266117a2a129SWilliam Breathitt Gray Expose ISA bus device drivers and options available for selection and 266217a2a129SWilliam Breathitt Gray configuration. Enable this option if your target machine has an ISA 266317a2a129SWilliam Breathitt Gray bus. ISA is an older system, displaced by PCI and newer bus 266417a2a129SWilliam Breathitt Gray architectures -- if your target machine is modern, it probably does 266517a2a129SWilliam Breathitt Gray not have an ISA bus. 26663a495511SWilliam Breathitt Gray 26673a495511SWilliam Breathitt Gray If unsure, say N. 26683a495511SWilliam Breathitt Gray 26691c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2670e279b6c1SSam Ravnborgconfig ISA_DMA_API 26711c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26721c00f016SDavid Rientjes default y 26731c00f016SDavid Rientjes help 26741c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26751c00f016SDavid Rientjes If unsure, say Y. 2676e279b6c1SSam Ravnborg 267751e68d05SLinus Torvaldsif X86_32 267851e68d05SLinus Torvalds 2679e279b6c1SSam Ravnborgconfig ISA 2680e279b6c1SSam Ravnborg bool "ISA support" 26818f9ca475SIngo Molnar ---help--- 2682e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2683e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2684e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2685e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2686e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2687e279b6c1SSam Ravnborg 2688e279b6c1SSam Ravnborgconfig SCx200 2689e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26908f9ca475SIngo Molnar ---help--- 2691e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2692e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2693e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2694e279b6c1SSam Ravnborg for other scx200_* drivers. 2695e279b6c1SSam Ravnborg 2696e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2697e279b6c1SSam Ravnborg 2698e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2699e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2700592913ecSJohn Stultz depends on SCx200 2701e279b6c1SSam Ravnborg default y 27028f9ca475SIngo Molnar ---help--- 2703e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2704e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2705e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2706e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2707e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2708e279b6c1SSam Ravnborg 27093ef0e1f8SAndres Salomonconfig OLPC 27103ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 271154008979SThomas Gleixner depends on !X86_PAE 27123c554946SAndres Salomon select GPIOLIB 2713dc3119e7SThomas Gleixner select OF 271445bb1674SDaniel Drake select OF_PROMTREE 2715b4e51854SGrant Likely select IRQ_DOMAIN 27168f9ca475SIngo Molnar ---help--- 27173ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 27183ef0e1f8SAndres Salomon XO hardware. 27193ef0e1f8SAndres Salomon 2720a3128588SDaniel Drakeconfig OLPC_XO1_PM 2721a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 2722fa112cf1SBorislav Petkov depends on OLPC && MFD_CS5535=y && PM_SLEEP 2723bf1ebf00SDaniel Drake ---help--- 272497c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2725bf1ebf00SDaniel Drake 2726cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2727cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2728cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2729cfee9597SDaniel Drake ---help--- 2730cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2731cfee9597SDaniel Drake programmable wakeup source. 2732cfee9597SDaniel Drake 27337feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27347feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 273592e830f2SArnd Bergmann depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2736ed8e47feSRandy Dunlap depends on INPUT=y 2737d8d01a63SDaniel Drake select POWER_SUPPLY 27387feda8e9SDaniel Drake ---help--- 27397feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27407bc74b3dSDaniel Drake - EC-driven system wakeups 27417feda8e9SDaniel Drake - Power button 27427bc74b3dSDaniel Drake - Ebook switch 27432cf2baeaSDaniel Drake - Lid switch 2744e1040ac6SDaniel Drake - AC adapter status updates 2745e1040ac6SDaniel Drake - Battery status updates 27467feda8e9SDaniel Drake 2747a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2748a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2749d8d01a63SDaniel Drake depends on OLPC && ACPI 2750d8d01a63SDaniel Drake select POWER_SUPPLY 2751a0f30f59SDaniel Drake ---help--- 2752a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2753a0f30f59SDaniel Drake - EC-driven system wakeups 2754a0f30f59SDaniel Drake - AC adapter status updates 2755a0f30f59SDaniel Drake - Battery status updates 2756e279b6c1SSam Ravnborg 2757d4f3e350SEd Wildgooseconfig ALIX 2758d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2759d4f3e350SEd Wildgoose select GPIOLIB 2760d4f3e350SEd Wildgoose ---help--- 2761d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2762d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2763d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2764d4f3e350SEd Wildgoose get added here. 2765d4f3e350SEd Wildgoose 2766d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2767d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2768d4f3e350SEd Wildgoose 2769d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2770d4f3e350SEd Wildgoose 2771da4e3302SPhilip Prindevilleconfig NET5501 2772da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2773da4e3302SPhilip Prindeville select GPIOLIB 2774da4e3302SPhilip Prindeville ---help--- 2775da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2776da4e3302SPhilip Prindeville 27773197059aSPhilip A. Prindevilleconfig GEOS 27783197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27793197059aSPhilip A. Prindeville select GPIOLIB 27803197059aSPhilip A. Prindeville depends on DMI 27813197059aSPhilip A. Prindeville ---help--- 27823197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27833197059aSPhilip A. Prindeville 27847d029125SVivien Didelotconfig TS5500 27857d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27867d029125SVivien Didelot depends on MELAN 27877d029125SVivien Didelot select CHECK_SIGNATURE 27887d029125SVivien Didelot select NEW_LEDS 27897d029125SVivien Didelot select LEDS_CLASS 27907d029125SVivien Didelot ---help--- 27917d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27927d029125SVivien Didelot 2793e279b6c1SSam Ravnborgendif # X86_32 2794e279b6c1SSam Ravnborg 279523ac4ae8SAndreas Herrmannconfig AMD_NB 2796e279b6c1SSam Ravnborg def_bool y 27970e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2798e279b6c1SSam Ravnborg 2799e3263ab3SDavid Herrmannconfig X86_SYSFB 2800e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2801e3263ab3SDavid Herrmann help 2802e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2803e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2804e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2805e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2806e3263ab3SDavid Herrmann to x86. 2807e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2808e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2809e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2810e3a5dc08SNikolas Nyby modes, it is advertised as fallback platform framebuffer so legacy 2811e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2812e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2813e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2814e3263ab3SDavid Herrmann 2815e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2816e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2817e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2818e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2819e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2820e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2821e3263ab3SDavid Herrmann incompatible with simplefb. 2822e3263ab3SDavid Herrmann 2823e3263ab3SDavid Herrmann If unsure, say Y. 2824e3263ab3SDavid Herrmann 2825e279b6c1SSam Ravnborgendmenu 2826e279b6c1SSam Ravnborg 2827e279b6c1SSam Ravnborg 28281572497cSChristoph Hellwigmenu "Binary Emulations" 2829e279b6c1SSam Ravnborg 2830e279b6c1SSam Ravnborgconfig IA32_EMULATION 2831e279b6c1SSam Ravnborg bool "IA32 Emulation" 2832e279b6c1SSam Ravnborg depends on X86_64 283339f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2834d1603990SRandy Dunlap select BINFMT_ELF 2835a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 283639f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28378f9ca475SIngo Molnar ---help--- 28385fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28395fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28405fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2841e279b6c1SSam Ravnborg 2842e279b6c1SSam Ravnborgconfig IA32_AOUT 2843e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28446b213e1bSDavid Woodhouse depends on IA32_EMULATION 2845eac61655SBorislav Petkov depends on BROKEN 28468f9ca475SIngo Molnar ---help--- 2847e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2848e279b6c1SSam Ravnborg 28490bf62763SH. Peter Anvinconfig X86_X32 28506ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28519b54050bSBrian Gerst depends on X86_64 28525fd92e65SH. J. Lu ---help--- 28535fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28545fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28555fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28565fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28575fd92e65SH. J. Lu 28585fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 28595fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 28605fd92e65SH. J. Lu option set. 28615fd92e65SH. J. Lu 2862953fee1dSIngo Molnarconfig COMPAT_32 2863953fee1dSIngo Molnar def_bool y 2864953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2865953fee1dSIngo Molnar select HAVE_UID16 2866953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2867953fee1dSIngo Molnar 2868e279b6c1SSam Ravnborgconfig COMPAT 28693c2362e6SHarvey Harrison def_bool y 28700bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2871e279b6c1SSam Ravnborg 28723120e25eSJan Beulichif COMPAT 2873e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28743120e25eSJan Beulich def_bool y 2875e279b6c1SSam Ravnborg 2876e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28773c2362e6SHarvey Harrison def_bool y 28783120e25eSJan Beulich depends on SYSVIPC 28793120e25eSJan Beulichendif 2880ee009e4aSDavid Howells 2881e279b6c1SSam Ravnborgendmenu 2882e279b6c1SSam Ravnborg 2883e279b6c1SSam Ravnborg 2884e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2885e5beae16SKeith Packard def_bool y 2886e5beae16SKeith Packard depends on X86_32 2887e5beae16SKeith Packard 28884692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28894692d77fSAlessandro Rubini bool 2890f7219a53SAlessandro Rubini 2891e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2892e585513bSKirill A. Shutemov def_bool y 2893e585513bSKirill A. Shutemov 2894e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2895e279b6c1SSam Ravnborg 2896edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2897