1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 2daa93fabSSam Ravnborg# Select 32 or 64 bit 3daa93fabSSam Ravnborgconfig 64BIT 46840999bSSam Ravnborg bool "64-bit kernel" if ARCH = "x86" 5ffee0de4SDavid Woodhouse default ARCH != "i386" 68f9ca475SIngo Molnar ---help--- 7daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 8daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 9daa93fabSSam Ravnborg 10daa93fabSSam Ravnborgconfig X86_32 113120e25eSJan Beulich def_bool y 123120e25eSJan Beulich depends on !64BIT 13341c787eSIngo Molnar # Options that are inherently 32-bit kernel only: 14341c787eSIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION 15341c787eSIngo Molnar select CLKSRC_I8253 16341c787eSIngo Molnar select CLONE_BACKWARDS 17341c787eSIngo Molnar select HAVE_AOUT 18341c787eSIngo Molnar select HAVE_GENERIC_DMA_COHERENT 19341c787eSIngo Molnar select MODULES_USE_ELF_REL 20341c787eSIngo Molnar select OLD_SIGACTION 21daa93fabSSam Ravnborg 22daa93fabSSam Ravnborgconfig X86_64 233120e25eSJan Beulich def_bool y 243120e25eSJan Beulich depends on 64BIT 25d94e0685SIngo Molnar # Options that are inherently 64-bit kernel only: 26e1073d1eSAneesh Kumar K.V select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA 27d94e0685SIngo Molnar select ARCH_SUPPORTS_INT128 28d94e0685SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF 29d94e0685SIngo Molnar select HAVE_ARCH_SOFT_DIRTY 30d94e0685SIngo Molnar select MODULES_USE_ELF_RELA 31d94e0685SIngo Molnar select X86_DEV_DMA_OPS 32f8781c4aSDominik Brodowski select ARCH_HAS_SYSCALL_WRAPPER 331032c0baSSam Ravnborg 34d94e0685SIngo Molnar# 35d94e0685SIngo Molnar# Arch settings 36d94e0685SIngo Molnar# 37d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 38d94e0685SIngo Molnar# ported to 32-bit as well. ) 39d94e0685SIngo Molnar# 408d5fffb9SSam Ravnborgconfig X86 413c2362e6SHarvey Harrison def_bool y 42c763ea26SIngo Molnar # 43c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 44c763ea26SIngo Molnar # 456471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 466e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 476471b825SIngo Molnar select ANON_INODES 486471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 496471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 5091dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 51fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5221266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 536471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5472d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 55316d097cSDave Hansen select ARCH_HAS_FILTER_PGPROT 566974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 57957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 585c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 5910bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 60c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 6139208aa7SKees Cook select ARCH_HAS_REFCOUNT 620aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 63*8780356eSDan Williams select ARCH_HAS_UACCESS_MCSAFE if X86_64 64d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 656471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 66ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 67ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 68ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 69c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 7065f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 716471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 726471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 7377fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 745e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 756471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 766471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 776471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 786471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 796471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 80ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 81c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 8238d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 836471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 846471b825SIngo Molnar select CLKEVT_I8253 856471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 866471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 876471b825SIngo Molnar select DCACHE_WORD_ACCESS 88fec777c3SChristoph Hellwig select DMA_DIRECT_OPS 8945471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 9045471cd9SLinus Torvalds select EDAC_SUPPORT 916471b825SIngo Molnar select GENERIC_CLOCKEVENTS 926471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 936471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 946471b825SIngo Molnar select GENERIC_CMOS_UPDATE 956471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 9661dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 976471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 986471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 996471b825SIngo Molnar select GENERIC_IOMAP 100c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 1010fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 102ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1036471b825SIngo Molnar select GENERIC_IRQ_PROBE 104c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1056471b825SIngo Molnar select GENERIC_IRQ_SHOW 1066471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1076471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1086471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1096471b825SIngo Molnar select GENERIC_STRNLEN_USER 1106471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1117edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1126471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1136471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1146471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1156471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1166471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1176471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 118d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1196471b825SIngo Molnar select HAVE_ARCH_KGDB 1209e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1219e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1221b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 1236471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 124f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 1256471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1266471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 127a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 128e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 129c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1306471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 1316471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1326471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1336471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 134c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1356471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1366471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1376471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1386471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1399c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 140677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 14106aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 142c763ea26SIngo Molnar select HAVE_EBPF_JIT if X86_64 14358340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1445f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 145644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1466471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1476471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1486471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1496b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1500067f129SK.Prasad select HAVE_HW_BREAKPOINT 1516471b825SIngo Molnar select HAVE_IDE 1526471b825SIngo Molnar select HAVE_IOREMAP_PROT 1536471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1546471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1556471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1566471b825SIngo Molnar select HAVE_KERNEL_GZIP 1576471b825SIngo Molnar select HAVE_KERNEL_LZ4 1586471b825SIngo Molnar select HAVE_KERNEL_LZMA 1596471b825SIngo Molnar select HAVE_KERNEL_LZO 1606471b825SIngo Molnar select HAVE_KERNEL_XZ 1616471b825SIngo Molnar select HAVE_KPROBES 1626471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 163540adea3SMasami Hiramatsu select HAVE_FUNCTION_ERROR_INJECTION 1646471b825SIngo Molnar select HAVE_KRETPROBES 1656471b825SIngo Molnar select HAVE_KVM 1666471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1676471b825SIngo Molnar select HAVE_MEMBLOCK 1686471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1690102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 170ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 17142a0bb3fSPetr Mladek select HAVE_NMI 1726471b825SIngo Molnar select HAVE_OPROFILE 1736471b825SIngo Molnar select HAVE_OPTPROBES 1746471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1756471b825SIngo Molnar select HAVE_PERF_EVENTS 176c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 17792e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 178c5e63197SJiri Olsa select HAVE_PERF_REGS 179c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1809e52fc2bSVitaly Kuznetsov select HAVE_RCU_TABLE_FREE 1816471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 18211af8474SJosh Poimboeuf select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION 183c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 1846471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1856471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1867c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 187c0185808SThomas Gleixner select IRQ_FORCED_THREADING 188df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 1896471b825SIngo Molnar select PERF_EVENTS 1903195ef59SPrarit Bhargava select RTC_LIB 191d6faca40SArnd Bergmann select RTC_MC146818_LIB 1926471b825SIngo Molnar select SPARSE_IRQ 19383fe27eaSPranith Kumar select SRCU 1946471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 19515f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 1966471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1976471b825SIngo Molnar select VIRT_TO_BUS 1986471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1997d8330a5SBalbir Singh 200ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 2013120e25eSJan Beulich def_bool y 2023120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 203ba7e4d13SIngo Molnar 20451b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 20551b26adaSLinus Torvalds string 20651b26adaSLinus Torvalds default "elf32-i386" if X86_32 20751b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 20851b26adaSLinus Torvalds 20973531905SSam Ravnborgconfig ARCH_DEFCONFIG 210b9b39bfbSSam Ravnborg string 21173531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 21273531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 213b9b39bfbSSam Ravnborg 2148d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2153c2362e6SHarvey Harrison def_bool y 2168d5fffb9SSam Ravnborg 2178d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2183c2362e6SHarvey Harrison def_bool y 2198d5fffb9SSam Ravnborg 2208d5fffb9SSam Ravnborgconfig MMU 2213c2362e6SHarvey Harrison def_bool y 2228d5fffb9SSam Ravnborg 2239e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2249e08f57dSDaniel Cashman default 28 if 64BIT 2259e08f57dSDaniel Cashman default 8 2269e08f57dSDaniel Cashman 2279e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2289e08f57dSDaniel Cashman default 32 if 64BIT 2299e08f57dSDaniel Cashman default 16 2309e08f57dSDaniel Cashman 2319e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2329e08f57dSDaniel Cashman default 8 2339e08f57dSDaniel Cashman 2349e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2359e08f57dSDaniel Cashman default 16 2369e08f57dSDaniel Cashman 2378d5fffb9SSam Ravnborgconfig SBUS 2388d5fffb9SSam Ravnborg bool 2398d5fffb9SSam Ravnborg 2403bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2413120e25eSJan Beulich def_bool y 242a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2433bc4e459SFUJITA Tomonori 24418e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2454a14d84eSAndrew Morton def_bool y 24618e98307SFUJITA Tomonori 2478d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2483120e25eSJan Beulich def_bool y 2493120e25eSJan Beulich depends on ISA_DMA_API 2508d5fffb9SSam Ravnborg 2518d5fffb9SSam Ravnborgconfig GENERIC_BUG 2523c2362e6SHarvey Harrison def_bool y 2538d5fffb9SSam Ravnborg depends on BUG 254b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 255b93a531eSJan Beulich 256b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 257b93a531eSJan Beulich bool 2588d5fffb9SSam Ravnborg 2598d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2603c2362e6SHarvey Harrison def_bool y 2618d5fffb9SSam Ravnborg 2628d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2633120e25eSJan Beulich def_bool y 2643120e25eSJan Beulich depends on ISA_DMA_API 2658d5fffb9SSam Ravnborg 2661032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2673120e25eSJan Beulich def_bool y 2681032c0baSSam Ravnborg 2691032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2701032c0baSSam Ravnborg def_bool y 2711032c0baSSam Ravnborg 2729a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2739a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2748d5fffb9SSam Ravnborg 2751b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2761b27d05bSPekka Enberg def_bool y 2771b27d05bSPekka Enberg 278316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT 279316d097cSDave Hansen def_bool y 280316d097cSDave Hansen 281dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 28289c9c4c5SBrian Gerst def_bool y 283b32ef636Stravis@sgi.com 28408fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 28508fc4580STejun Heo def_bool y 28608fc4580STejun Heo 28708fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 28811124411STejun Heo def_bool y 28911124411STejun Heo 290801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 291801e4062SJohannes Berg def_bool y 292801e4062SJohannes Berg 293f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 294f4cb5700SJohannes Berg def_bool y 295f4cb5700SJohannes Berg 296cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 297cfe28c5dSSteve Capper def_bool y 298cfe28c5dSSteve Capper 29953313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 30053313b2cSSteve Capper def_bool y 30153313b2cSSteve Capper 3028d5fffb9SSam Ravnborgconfig ZONE_DMA32 303e0fd24a3SJan Beulich def_bool y if X86_64 3048d5fffb9SSam Ravnborg 3058d5fffb9SSam Ravnborgconfig AUDIT_ARCH 306e0fd24a3SJan Beulich def_bool y if X86_64 3078d5fffb9SSam Ravnborg 308765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 309765c68bdSIngo Molnar def_bool y 310765c68bdSIngo Molnar 3116a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3126a11f75bSAkinobu Mita def_bool y 3136a11f75bSAkinobu Mita 314d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 315d6f2d75aSAndrey Ryabinin hex 316d6f2d75aSAndrey Ryabinin depends on KASAN 317d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 318d6f2d75aSAndrey Ryabinin 31969575d38SShane Wangconfig HAVE_INTEL_TXT 32069575d38SShane Wang def_bool y 3216ea30386SKees Cook depends on INTEL_IOMMU && ACPI 32269575d38SShane Wang 3236b0c3d44SSam Ravnborgconfig X86_32_SMP 3246b0c3d44SSam Ravnborg def_bool y 3256b0c3d44SSam Ravnborg depends on X86_32 && SMP 3266b0c3d44SSam Ravnborg 3276b0c3d44SSam Ravnborgconfig X86_64_SMP 3286b0c3d44SSam Ravnborg def_bool y 3296b0c3d44SSam Ravnborg depends on X86_64 && SMP 3306b0c3d44SSam Ravnborg 331ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 332ccbeed3aSTejun Heo def_bool y 3332bc2f688SKees Cook depends on X86_32 && CC_STACKPROTECTOR_NONE 334ccbeed3aSTejun Heo 3352b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3362b144498SSrikar Dronamraju def_bool y 3372b144498SSrikar Dronamraju 338d20642f0SRob Herringconfig FIX_EARLYCON_MEM 339d20642f0SRob Herring def_bool y 340d20642f0SRob Herring 34198233368SKirill A. Shutemovconfig PGTABLE_LEVELS 34298233368SKirill A. Shutemov int 34377ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 34498233368SKirill A. Shutemov default 4 if X86_64 34598233368SKirill A. Shutemov default 3 if X86_PAE 34698233368SKirill A. Shutemov default 2 34798233368SKirill A. Shutemov 348506f1d07SSam Ravnborgsource "init/Kconfig" 349dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3508d5fffb9SSam Ravnborg 351506f1d07SSam Ravnborgmenu "Processor type and features" 352506f1d07SSam Ravnborg 3535ee71535SRandy Dunlapconfig ZONE_DMA 3545ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3555ee71535SRandy Dunlap default y 3565ee71535SRandy Dunlap help 3575ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3585ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3595ee71535SRandy Dunlap Disable if no such devices will be used. 3605ee71535SRandy Dunlap 3615ee71535SRandy Dunlap If unsure, say Y. 3625ee71535SRandy Dunlap 363506f1d07SSam Ravnborgconfig SMP 364506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 365506f1d07SSam Ravnborg ---help--- 366506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3674a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3684a474157SRobert Graffham than one CPU, say Y. 369506f1d07SSam Ravnborg 3704a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 371506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 372506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3734a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 374506f1d07SSam Ravnborg will run faster if you say N here. 375506f1d07SSam Ravnborg 376506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 377506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 378506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 379506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 380506f1d07SSam Ravnborg 381506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 382506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 383506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 384506f1d07SSam Ravnborg 385395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 386c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 387506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 388506f1d07SSam Ravnborg 389506f1d07SSam Ravnborg If you don't know what to do here, say N. 390506f1d07SSam Ravnborg 3919def39beSJosh Triplettconfig X86_FEATURE_NAMES 3929def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3939def39beSJosh Triplett default y 3949def39beSJosh Triplett ---help--- 3959def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3969def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3979def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3989def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3999def39beSJosh Triplett 4009def39beSJosh Triplett If in doubt, say Y. 4019def39beSJosh Triplett 40206cd9a7dSYinghai Luconfig X86_X2APIC 40306cd9a7dSYinghai Lu bool "Support x2apic" 40419e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 40506cd9a7dSYinghai Lu ---help--- 40606cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 40706cd9a7dSYinghai Lu 40806cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 40906cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 41006cd9a7dSYinghai Lu 41106cd9a7dSYinghai Lu If you don't know what to do here, say N. 41206cd9a7dSYinghai Lu 4136695c85bSYinghai Luconfig X86_MPPARSE 4146e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4157a527688SJan Beulich default y 4165ab74722SIngo Molnar depends on X86_LOCAL_APIC 4178f9ca475SIngo Molnar ---help--- 4186695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4196695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4206695c85bSYinghai Lu 421ddd70cf9SJun Nakajimaconfig GOLDFISH 422ddd70cf9SJun Nakajima def_bool y 423ddd70cf9SJun Nakajima depends on X86_GOLDFISH 424ddd70cf9SJun Nakajima 42576b04384SDavid Woodhouseconfig RETPOLINE 42676b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 42776b04384SDavid Woodhouse default y 428d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 42976b04384SDavid Woodhouse help 43076b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 43176b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 43276b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 43376b04384SDavid Woodhouse support for full protection. The kernel may run slower. 43476b04384SDavid Woodhouse 43576b04384SDavid Woodhouse Without compiler support, at least indirect branches in assembler 43676b04384SDavid Woodhouse code are eliminated. Since this includes the syscall entry path, 43776b04384SDavid Woodhouse it is not entirely pointless. 43876b04384SDavid Woodhouse 439f01d7d51SVikas Shivappaconfig INTEL_RDT 440f01d7d51SVikas Shivappa bool "Intel Resource Director Technology support" 44178e99b4aSFenghua Yu default n 44278e99b4aSFenghua Yu depends on X86 && CPU_SUP_INTEL 44359fe5a77SThomas Gleixner select KERNFS 44478e99b4aSFenghua Yu help 445f01d7d51SVikas Shivappa Select to enable resource allocation and monitoring which are 446f01d7d51SVikas Shivappa sub-features of Intel Resource Director Technology(RDT). More 447f01d7d51SVikas Shivappa information about RDT can be found in the Intel x86 448f01d7d51SVikas Shivappa Architecture Software Developer Manual. 44978e99b4aSFenghua Yu 45078e99b4aSFenghua Yu Say N if unsure. 45178e99b4aSFenghua Yu 4528425091fSRavikiran G Thirumalaiif X86_32 453a0d0bb4dSRandy Dunlapconfig X86_BIGSMP 454a0d0bb4dSRandy Dunlap bool "Support for big SMP systems with more than 8 CPUs" 455a0d0bb4dSRandy Dunlap depends on SMP 456a0d0bb4dSRandy Dunlap ---help--- 457a0d0bb4dSRandy Dunlap This option is needed for the systems that have more than 8 CPUs 458a0d0bb4dSRandy Dunlap 459c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 460c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 461c5c606d9SRavikiran G Thirumalai default y 4628f9ca475SIngo Molnar ---help--- 46306ac8346SIngo Molnar If you disable this option then the kernel will only support 46406ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 46506ac8346SIngo Molnar systems out there.) 46606ac8346SIngo Molnar 4678425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4688425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 469cb7b8023SBen Hutchings Goldfish (Android emulator) 4708425091fSRavikiran G Thirumalai AMD Elan 4718425091fSRavikiran G Thirumalai RDC R-321x SoC 4728425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 47383125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4743f4110a4SThomas Gleixner Moorestown MID devices 47506ac8346SIngo Molnar 47606ac8346SIngo Molnar If you have one of these systems, or if you want to build a 47706ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4788425091fSRavikiran G Thirumalaiendif 47906ac8346SIngo Molnar 4808425091fSRavikiran G Thirumalaiif X86_64 4818425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4828425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4838425091fSRavikiran G Thirumalai default y 4848425091fSRavikiran G Thirumalai ---help--- 4858425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4868425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4878425091fSRavikiran G Thirumalai systems out there.) 4888425091fSRavikiran G Thirumalai 4898425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4908425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 49144b111b5SSteffen Persvold Numascale NumaChip 4928425091fSRavikiran G Thirumalai ScaleMP vSMP 4938425091fSRavikiran G Thirumalai SGI Ultraviolet 4948425091fSRavikiran G Thirumalai 4958425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4968425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4978425091fSRavikiran G Thirumalaiendif 498c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 499c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 50044b111b5SSteffen Persvoldconfig X86_NUMACHIP 50144b111b5SSteffen Persvold bool "Numascale NumaChip" 50244b111b5SSteffen Persvold depends on X86_64 50344b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 50444b111b5SSteffen Persvold depends on NUMA 50544b111b5SSteffen Persvold depends on SMP 50644b111b5SSteffen Persvold depends on X86_X2APIC 507f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 50844b111b5SSteffen Persvold ---help--- 50944b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 51044b111b5SSteffen Persvold enable more than ~168 cores. 51144b111b5SSteffen Persvold If you don't have one of these, you should say N here. 51203b48632SNick Piggin 5136a48565eSIngo Molnarconfig X86_VSMP 514c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5156276a074SBorislav Petkov select HYPERVISOR_GUEST 5166a48565eSIngo Molnar select PARAVIRT 5176a48565eSIngo Molnar depends on X86_64 && PCI 518c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 519ead91d4bSShai Fultheim depends on SMP 5208f9ca475SIngo Molnar ---help--- 5216a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5226a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5236a48565eSIngo Molnar if you have one of these machines. 5246a48565eSIngo Molnar 525c5c606d9SRavikiran G Thirumalaiconfig X86_UV 526c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 527c5c606d9SRavikiran G Thirumalai depends on X86_64 528c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 52954c28d29SJack Steiner depends on NUMA 5301ecb4ae5SAndrew Morton depends on EFI 5319d6c26e7SSuresh Siddha depends on X86_X2APIC 5321222e564SIngo Molnar depends on PCI 533c5c606d9SRavikiran G Thirumalai ---help--- 534c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 535c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 536c5c606d9SRavikiran G Thirumalai 537c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 538c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 539506f1d07SSam Ravnborg 540ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 541ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 542cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 543ddd70cf9SJun Nakajima ---help--- 544ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 545ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 546ddd70cf9SJun Nakajima Goldfish emulator say N here. 547ddd70cf9SJun Nakajima 548c751e17bSThomas Gleixnerconfig X86_INTEL_CE 549c751e17bSThomas Gleixner bool "CE4100 TV platform" 550c751e17bSThomas Gleixner depends on PCI 551c751e17bSThomas Gleixner depends on PCI_GODIRECT 5526084a6e2SJiang Liu depends on X86_IO_APIC 553c751e17bSThomas Gleixner depends on X86_32 554c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 55537bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 556da6b737bSSebastian Andrzej Siewior select OF 557da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 558c751e17bSThomas Gleixner ---help--- 559c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 560c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 561c751e17bSThomas Gleixner boxes and media devices. 562c751e17bSThomas Gleixner 5634cb9b00fSDavid Cohenconfig X86_INTEL_MID 56443605ef1SAlan Cox bool "Intel MID platform support" 56543605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 566edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5671ea7c673SAlan Cox depends on PCI 5683fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5691ea7c673SAlan Cox depends on X86_IO_APIC 5707c9c3a1eSAlan Cox select SFI 5714cb9b00fSDavid Cohen select I2C 5727c9c3a1eSAlan Cox select DW_APB_TIMER 5731ea7c673SAlan Cox select APB_TIMER 5741ea7c673SAlan Cox select INTEL_SCU_IPC 57515a713dfSMika Westerberg select MFD_INTEL_MSIC 5761ea7c673SAlan Cox ---help--- 5774cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5784cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5794cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5801ea7c673SAlan Cox 5814cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5824cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 58343605ef1SAlan Cox 5848bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5858bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5868bbc2a13SBryan O'Donoghue depends on X86_32 5878bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5888bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5898bbc2a13SBryan O'Donoghue depends on X86_TSC 5908bbc2a13SBryan O'Donoghue depends on PCI 5918bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5928bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5938bbc2a13SBryan O'Donoghue select IOSF_MBI 5948bbc2a13SBryan O'Donoghue select INTEL_IMR 5959ab6eb51SAndy Shevchenko select COMMON_CLK 5968bbc2a13SBryan O'Donoghue ---help--- 5978bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5988bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5998bbc2a13SBryan O'Donoghue compatible Intel Galileo. 6008bbc2a13SBryan O'Donoghue 6013d48aab1SMika Westerbergconfig X86_INTEL_LPSS 6023d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 603eebb3e8dSAndy Shevchenko depends on X86 && ACPI 6043d48aab1SMika Westerberg select COMMON_CLK 6050f531431SMathias Nyman select PINCTRL 606eebb3e8dSAndy Shevchenko select IOSF_MBI 6073d48aab1SMika Westerberg ---help--- 6083d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6093d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6100f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6110f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6123d48aab1SMika Westerberg 61392082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 61492082a88SKen Xue bool "AMD ACPI2Platform devices support" 61592082a88SKen Xue depends on ACPI 61692082a88SKen Xue select COMMON_CLK 61792082a88SKen Xue select PINCTRL 61892082a88SKen Xue ---help--- 61992082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 62092082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 62192082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 62292082a88SKen Xue implemented under PINCTRL subsystem. 62392082a88SKen Xue 624ced3ce76SDavid E. Boxconfig IOSF_MBI 625ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 626ced3ce76SDavid E. Box depends on PCI 627ced3ce76SDavid E. Box ---help--- 628ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 629ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 630ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 631ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 632ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 633ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 634ced3ce76SDavid E. Box This list is not meant to be exclusive. 635ced3ce76SDavid E. Box - BayTrail 636ced3ce76SDavid E. Box - Braswell 637ced3ce76SDavid E. Box - Quark 638ced3ce76SDavid E. Box 639ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 640ced3ce76SDavid E. Box 641ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 642ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 643ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 644ed2226bdSDavid E. Box ---help--- 645ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 646ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 647ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 648ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 649ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 650ed2226bdSDavid E. Box device they want to access. 651ed2226bdSDavid E. Box 652ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 653ed2226bdSDavid E. Box 654c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 655c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 656506f1d07SSam Ravnborg depends on X86_32 657c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 658c5c606d9SRavikiran G Thirumalai select M486 659c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 660c5c606d9SRavikiran G Thirumalai ---help--- 661c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 662c5c606d9SRavikiran G Thirumalai as R-8610-(G). 663c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 664c5c606d9SRavikiran G Thirumalai 665e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6669c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6679c398017SIngo Molnar depends on X86_32 && SMP 668c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6698f9ca475SIngo Molnar ---help--- 670b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 671b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 672b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 673b5660ba7SH. Peter Anvin one and will fallback to default. 674d49c4288SYinghai Lu 675c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 676d49c4288SYinghai Lu 677d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6786fc108a0SJan Beulich def_bool y 679d949f36fSLinus Torvalds # MCE code calls memory_failure(): 680d949f36fSLinus Torvalds depends on X86_MCE 681d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 682d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 683d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 684d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 685d949f36fSLinus Torvalds 68683125a3aSAlessandro Rubiniconfig STA2X11 68783125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 68883125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 689b6e05477SChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 69083125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 69183125a3aSAlessandro Rubini select X86_DMA_REMAP 69283125a3aSAlessandro Rubini select SWIOTLB 69383125a3aSAlessandro Rubini select MFD_STA2X11 6940145071bSLinus Walleij select GPIOLIB 69583125a3aSAlessandro Rubini default n 69683125a3aSAlessandro Rubini ---help--- 69783125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 69883125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 69983125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 70083125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 70183125a3aSAlessandro Rubini standard PC machines. 70283125a3aSAlessandro Rubini 70382148d1dSShérabconfig X86_32_IRIS 70482148d1dSShérab tristate "Eurobraille/Iris poweroff module" 70582148d1dSShérab depends on X86_32 70682148d1dSShérab ---help--- 70782148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 70882148d1dSShérab to shut themselves down properly. A special I/O sequence is 70982148d1dSShérab needed to do so, which is what this module does at 71082148d1dSShérab kernel shutdown. 71182148d1dSShérab 71282148d1dSShérab This is only for Iris machines from EuroBraille. 71382148d1dSShérab 71482148d1dSShérab If unused, say N. 71582148d1dSShérab 716ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7173c2362e6SHarvey Harrison def_bool y 7183c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 719a87d0914SKen Chen depends on X86 7208f9ca475SIngo Molnar ---help--- 721506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 722506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 723506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 724506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 725506f1d07SSam Ravnborg 726506f1d07SSam Ravnborg If in doubt, say "Y". 727506f1d07SSam Ravnborg 7286276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7296276a074SBorislav Petkov bool "Linux guest support" 7308f9ca475SIngo Molnar ---help--- 7316276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7326276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7336276a074SBorislav Petkov setup. 734506f1d07SSam Ravnborg 7356276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7366276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 737506f1d07SSam Ravnborg 7386276a074SBorislav Petkovif HYPERVISOR_GUEST 739506f1d07SSam Ravnborg 740e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 741e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7428f9ca475SIngo Molnar ---help--- 743e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 744e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 745e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 746e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 747e61bd94aSEduardo Pereira Habkost 7486276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7496276a074SBorislav Petkov bool "paravirt-ops debugging" 7506276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7516276a074SBorislav Petkov ---help--- 7526276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7536276a074SBorislav Petkov a paravirt_op is missing when it is called. 7546276a074SBorislav Petkov 755b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 756b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7576ea30386SKees Cook depends on PARAVIRT && SMP 758b4ecc126SJeremy Fitzhardinge ---help--- 759b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 760b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 761b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 762b4ecc126SJeremy Fitzhardinge 7634c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7644c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 765b4ecc126SJeremy Fitzhardinge 7664c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 767b4ecc126SJeremy Fitzhardinge 76845e898b7SWaiman Longconfig QUEUED_LOCK_STAT 76945e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 770cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 77145e898b7SWaiman Long ---help--- 77245e898b7SWaiman Long Enable the collection of statistical data on the slowpath 77345e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 77445e898b7SWaiman Long them on debugfs. 77545e898b7SWaiman Long 7766276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7776276a074SBorislav Petkov 7786276a074SBorislav Petkovconfig KVM_GUEST 7796276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7806276a074SBorislav Petkov depends on PARAVIRT 7816276a074SBorislav Petkov select PARAVIRT_CLOCK 7826276a074SBorislav Petkov default y 7836276a074SBorislav Petkov ---help--- 7846276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7856276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7866276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7876276a074SBorislav Petkov underlying device model, the host provides the guest with 7886276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7896276a074SBorislav Petkov 7901e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7911e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7921e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7931e20eb85SSrivatsa Vaddagiri default n 7941e20eb85SSrivatsa Vaddagiri ---help--- 7951e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7961e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7971e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7981e20eb85SSrivatsa Vaddagiri 7996276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 8006276a074SBorislav Petkov bool "Paravirtual steal time accounting" 8016276a074SBorislav Petkov depends on PARAVIRT 8026276a074SBorislav Petkov default n 8036276a074SBorislav Petkov ---help--- 8046276a074SBorislav Petkov Select this option to enable fine granularity task steal time 8056276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 8066276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8076276a074SBorislav Petkov that, there can be a small performance impact. 8086276a074SBorislav Petkov 8096276a074SBorislav Petkov If in doubt, say N here. 8106276a074SBorislav Petkov 8117af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8127af192c9SGerd Hoffmann bool 8137af192c9SGerd Hoffmann 8144a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8154a362601SJan Kiszka bool "Jailhouse non-root cell support" 816abde587bSArnd Bergmann depends on X86_64 && PCI 81787e65d05SJan Kiszka select X86_PM_TIMER 8184a362601SJan Kiszka ---help--- 8194a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8204a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8214a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8224a362601SJan Kiszka 8236276a074SBorislav Petkovendif #HYPERVISOR_GUEST 82497349135SJeremy Fitzhardinge 82508677214SYinghai Luconfig NO_BOOTMEM 826774ea0bcSYinghai Lu def_bool y 82708677214SYinghai Lu 828506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 829506f1d07SSam Ravnborg 830506f1d07SSam Ravnborgconfig HPET_TIMER 8313c2362e6SHarvey Harrison def_bool X86_64 832506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8338f9ca475SIngo Molnar ---help--- 834506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 835506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 836506f1d07SSam Ravnborg present. 837506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 838506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 839506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8404e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8414e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 842506f1d07SSam Ravnborg 843506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 844506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 845506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 846506f1d07SSam Ravnborg 847506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 848506f1d07SSam Ravnborg 849506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8503c2362e6SHarvey Harrison def_bool y 8519d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 852506f1d07SSam Ravnborg 853bb24c471SJacob Panconfig APB_TIMER 854933b9463SAlan Cox def_bool y if X86_INTEL_MID 855933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 85606c3df49SJamie Iles select DW_APB_TIMER 857a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 858bb24c471SJacob Pan help 859bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 860bb24c471SJacob Pan The APBT provides a stable time base on SMP 861bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 862bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 863bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 864bb24c471SJacob Pan 8656a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 866506f1d07SSam Ravnborg# The code disables itself when not needed. 8677ae9392cSThomas Petazzoniconfig DMI 8687ae9392cSThomas Petazzoni default y 869cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8706a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8718f9ca475SIngo Molnar ---help--- 8727ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8737ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8747ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8757ae9392cSThomas Petazzoni BIOS code. 8767ae9392cSThomas Petazzoni 877506f1d07SSam Ravnborgconfig GART_IOMMU 87838901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 879506f1d07SSam Ravnborg select SWIOTLB 88023ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8818f9ca475SIngo Molnar ---help--- 882ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 883ced3c42cSIngo Molnar GART based hardware IOMMUs. 884ced3c42cSIngo Molnar 885ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 886ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 887ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 888ced3c42cSIngo Molnar 889ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 890ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 891ced3c42cSIngo Molnar 892ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 893ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 894ced3c42cSIngo Molnar 32-bit limited device. 895ced3c42cSIngo Molnar 896ced3c42cSIngo Molnar If unsure, say Y. 897506f1d07SSam Ravnborg 898506f1d07SSam Ravnborgconfig CALGARY_IOMMU 899506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 900506f1d07SSam Ravnborg select SWIOTLB 9016ea30386SKees Cook depends on X86_64 && PCI 9028f9ca475SIngo Molnar ---help--- 903506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 904506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 905506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 906506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 907506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 908506f1d07SSam Ravnborg prevents them from going anywhere except their intended 909506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 910506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 911506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 912506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 913506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 914506f1d07SSam Ravnborg If unsure, say Y. 915506f1d07SSam Ravnborg 916506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9173c2362e6SHarvey Harrison def_bool y 9183c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 919506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9208f9ca475SIngo Molnar ---help--- 921506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 922506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 923506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 924506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 925506f1d07SSam Ravnborg If unsure, say Y. 926506f1d07SSam Ravnborg 927506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 928506f1d07SSam Ravnborgconfig SWIOTLB 929a1afd01cSJoerg Roedel def_bool y if X86_64 9308f9ca475SIngo Molnar ---help--- 931506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 9324454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 9334454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 9344454d327SJoe Millenbach with more than 3 GB of memory. 9354454d327SJoe Millenbach If unsure, say Y. 936506f1d07SSam Ravnborg 937a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 9383120e25eSJan Beulich def_bool y 9393120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 940d25e26b6SLinus Torvalds 9411184dc2fSMike Travisconfig MAXSMP 942ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9436ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 94436f5101aSMike Travis select CPUMASK_OFFSTACK 9458f9ca475SIngo Molnar ---help--- 946ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9471184dc2fSMike Travis If unsure, say N. 948506f1d07SSam Ravnborg 949aec6487eSIngo Molnar# 950aec6487eSIngo Molnar# The maximum number of CPUs supported: 951aec6487eSIngo Molnar# 952aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 953aec6487eSIngo Molnar# and which can be configured interactively in the 954aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 955aec6487eSIngo Molnar# 956aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on 957aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel. 958aec6487eSIngo Molnar# 959aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable 960aec6487eSIngo Molnar# interactive configuration. ) 961aec6487eSIngo Molnar# 962a0d0bb4dSRandy Dunlap 963aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN 964a0d0bb4dSRandy Dunlap int 965aec6487eSIngo Molnar default NR_CPUS_RANGE_END if MAXSMP 966a0d0bb4dSRandy Dunlap default 1 if !SMP 967a0d0bb4dSRandy Dunlap default 2 968a0d0bb4dSRandy Dunlap 969aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 970a0d0bb4dSRandy Dunlap int 971a0d0bb4dSRandy Dunlap depends on X86_32 972aec6487eSIngo Molnar default 64 if SMP && X86_BIGSMP 973aec6487eSIngo Molnar default 8 if SMP && !X86_BIGSMP 974a0d0bb4dSRandy Dunlap default 1 if !SMP 975a0d0bb4dSRandy Dunlap 976aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 977a0d0bb4dSRandy Dunlap int 978a0d0bb4dSRandy Dunlap depends on X86_64 979aec6487eSIngo Molnar default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 980aec6487eSIngo Molnar default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 981a0d0bb4dSRandy Dunlap default 1 if !SMP 982aec6487eSIngo Molnar 983aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 984aec6487eSIngo Molnar int 985aec6487eSIngo Molnar depends on X86_32 986aec6487eSIngo Molnar default 32 if X86_BIGSMP 987aec6487eSIngo Molnar default 8 if SMP 988aec6487eSIngo Molnar default 1 if !SMP 989aec6487eSIngo Molnar 990aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 991aec6487eSIngo Molnar int 992aec6487eSIngo Molnar depends on X86_64 993a0d0bb4dSRandy Dunlap default 8192 if MAXSMP 994a0d0bb4dSRandy Dunlap default 64 if SMP 995aec6487eSIngo Molnar default 1 if !SMP 996a0d0bb4dSRandy Dunlap 997506f1d07SSam Ravnborgconfig NR_CPUS 99836f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 999aec6487eSIngo Molnar range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 1000aec6487eSIngo Molnar default NR_CPUS_DEFAULT 10018f9ca475SIngo Molnar ---help--- 1002506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 1003bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 1004cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 1005506f1d07SSam Ravnborg minimum value which makes sense is 2. 1006506f1d07SSam Ravnborg 1007aec6487eSIngo Molnar This is purely to save memory: each supported CPU adds about 8KB 1008aec6487eSIngo Molnar to the kernel image. 1009506f1d07SSam Ravnborg 1010506f1d07SSam Ravnborgconfig SCHED_SMT 1011506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 1012c8e56d20SBorislav Petkov depends on SMP 10138f9ca475SIngo Molnar ---help--- 1014506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 1015506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 1016506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 1017506f1d07SSam Ravnborg N here. 1018506f1d07SSam Ravnborg 1019506f1d07SSam Ravnborgconfig SCHED_MC 10203c2362e6SHarvey Harrison def_bool y 10213c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 1022c8e56d20SBorislav Petkov depends on SMP 10238f9ca475SIngo Molnar ---help--- 1024506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 1025506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 1026506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 1027506f1d07SSam Ravnborg 1028de966cf4STim Chenconfig SCHED_MC_PRIO 1029de966cf4STim Chen bool "CPU core priorities scheduler support" 10300a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 10310a21fc12SIngo Molnar select X86_INTEL_PSTATE 10320a21fc12SIngo Molnar select CPU_FREQ 1033de966cf4STim Chen default y 10345e76b2abSTim Chen ---help--- 1035de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1036de966cf4STim Chen core ordering determined at manufacturing time, which allows 1037de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1038de966cf4STim Chen single threaded workloads) than others. 1039de966cf4STim Chen 1040de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1041de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1042de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1043de966cf4STim Chen overall system performance can be achieved. 1044de966cf4STim Chen 1045de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1046de966cf4STim Chen 1047de966cf4STim Chen If unsure say Y here. 10485e76b2abSTim Chen 1049506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 1050506f1d07SSam Ravnborg 105130b8b006SThomas Gleixnerconfig UP_LATE_INIT 105230b8b006SThomas Gleixner def_bool y 1053ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 105430b8b006SThomas Gleixner 1055506f1d07SSam Ravnborgconfig X86_UP_APIC 105650849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 105750849eefSJan Beulich default PCI_MSI 105838a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10598f9ca475SIngo Molnar ---help--- 1060506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1061506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1062506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1063506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1064506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1065506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1066506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1067506f1d07SSam Ravnborg lockups. 1068506f1d07SSam Ravnborg 1069506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1070506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1071506f1d07SSam Ravnborg depends on X86_UP_APIC 10728f9ca475SIngo Molnar ---help--- 1073506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1074506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1075506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1076506f1d07SSam Ravnborg 1077506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1078506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1079506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1080506f1d07SSam Ravnborg 1081506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10823c2362e6SHarvey Harrison def_bool y 10830dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1084b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 108552f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1086506f1d07SSam Ravnborg 1087506f1d07SSam Ravnborgconfig X86_IO_APIC 1088b1da1e71SJan Beulich def_bool y 1089b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1090506f1d07SSam Ravnborg 109141b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 109241b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 109341b9eb26SStefan Assmann depends on X86_IO_APIC 10948f9ca475SIngo Molnar ---help--- 109541b9eb26SStefan Assmann This option enables a workaround that fixes a source of 109641b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 109741b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 109841b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 109941b9eb26SStefan Assmann 110041b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 110141b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 110241b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 110341b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 110441b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 110541b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 110641b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 110741b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 110841b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 110941b9eb26SStefan Assmann down (vital) interrupt lines. 111041b9eb26SStefan Assmann 111141b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 111241b9eb26SStefan Assmann increased on these systems. 111341b9eb26SStefan Assmann 1114506f1d07SSam Ravnborgconfig X86_MCE 1115bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1116648ed940SChen, Gong select GENERIC_ALLOCATOR 1117e57dbaf7SBorislav Petkov default y 1118506f1d07SSam Ravnborg ---help--- 1119bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1120bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1121506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1122bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 11234efc0670SAndi Kleen 11245de97c9fSTony Luckconfig X86_MCELOG_LEGACY 11255de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 11265de97c9fSTony Luck depends on X86_MCE 11275de97c9fSTony Luck ---help--- 11285de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 11295de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 11305de97c9fSTony Luck rasdaemon solution. 11315de97c9fSTony Luck 1132506f1d07SSam Ravnborgconfig X86_MCE_INTEL 11333c2362e6SHarvey Harrison def_bool y 11343c2362e6SHarvey Harrison prompt "Intel MCE features" 1135c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 11368f9ca475SIngo Molnar ---help--- 1137506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1138506f1d07SSam Ravnborg the thermal monitor. 1139506f1d07SSam Ravnborg 1140506f1d07SSam Ravnborgconfig X86_MCE_AMD 11413c2362e6SHarvey Harrison def_bool y 11423c2362e6SHarvey Harrison prompt "AMD MCE features" 1143f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11448f9ca475SIngo Molnar ---help--- 1145506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1146506f1d07SSam Ravnborg the DRAM Error Threshold. 1147506f1d07SSam Ravnborg 11484efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11496fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1150c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11514efc0670SAndi Kleen ---help--- 11524efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11535065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11544efc0670SAndi Kleen line. 11554efc0670SAndi Kleen 1156b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1157b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11586fc108a0SJan Beulich def_bool y 1159b2762686SAndi Kleen 1160ea149b36SAndi Kleenconfig X86_MCE_INJECT 1161bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1162ea149b36SAndi Kleen tristate "Machine check injector support" 1163ea149b36SAndi Kleen ---help--- 1164ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1165ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1166ea149b36SAndi Kleen QA it is safe to say n. 1167ea149b36SAndi Kleen 11684efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11694efc0670SAndi Kleen def_bool y 11705bb38adcSAndi Kleen depends on X86_MCE_INTEL 11714efc0670SAndi Kleen 117207dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1173e633c65aSKan Liang 11745aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11751e642812SIngo Molnar bool "Legacy VM86 support" 11765aef51c3SAndy Lutomirski default n 1177506f1d07SSam Ravnborg depends on X86_32 11788f9ca475SIngo Molnar ---help--- 11795aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11805aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11815aef51c3SAndy Lutomirski 11825aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11835aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11845aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11855aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11865aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11871e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11881e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11891e642812SIngo Molnar mode might be faster than emulation and you might want to 11901e642812SIngo Molnar enable this option. 11915aef51c3SAndy Lutomirski 11921e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11931e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11941e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11951e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11965aef51c3SAndy Lutomirski 11971e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11981e642812SIngo Molnar and slows down exception handling a tiny bit. 11995aef51c3SAndy Lutomirski 12001e642812SIngo Molnar If unsure, say N here. 12015aef51c3SAndy Lutomirski 12025aef51c3SAndy Lutomirskiconfig VM86 12035aef51c3SAndy Lutomirski bool 12045aef51c3SAndy Lutomirski default X86_LEGACY_VM86 120534273f41SH. Peter Anvin 120634273f41SH. Peter Anvinconfig X86_16BIT 120734273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 120834273f41SH. Peter Anvin default y 1209a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 121034273f41SH. Peter Anvin ---help--- 121134273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 121234273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 121334273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 121434273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 121534273f41SH. Peter Anvin 121634273f41SH. Peter Anvinconfig X86_ESPFIX32 121734273f41SH. Peter Anvin def_bool y 121834273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1219506f1d07SSam Ravnborg 1220197725deSH. Peter Anvinconfig X86_ESPFIX64 1221197725deSH. Peter Anvin def_bool y 122234273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1223506f1d07SSam Ravnborg 12241ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 12251ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 12261ad83c85SAndy Lutomirski default y 12271ad83c85SAndy Lutomirski depends on X86_64 12281ad83c85SAndy Lutomirski ---help--- 12291ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 12301ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 12311ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 12321ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 12331ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 12341ad83c85SAndy Lutomirski 0xffffffffff600?00. 12351ad83c85SAndy Lutomirski 12361ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12371ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12381ad83c85SAndy Lutomirski 12391ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12401ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12411ad83c85SAndy Lutomirski 1242506f1d07SSam Ravnborgconfig TOSHIBA 1243506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1244506f1d07SSam Ravnborg depends on X86_32 1245506f1d07SSam Ravnborg ---help--- 1246506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1247506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1248506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1249506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1250506f1d07SSam Ravnborg 1251506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1252506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1253506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1254506f1d07SSam Ravnborg 1255506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1256506f1d07SSam Ravnborg Say N otherwise. 1257506f1d07SSam Ravnborg 1258506f1d07SSam Ravnborgconfig I8K 1259039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1260949a9d70SJean Delvare select HWMON 1261039ae585SPali Rohár select SENSORS_DELL_SMM 1262506f1d07SSam Ravnborg ---help--- 1263039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1264039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1265039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1266039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1267039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1268039ae585SPali Rohár needed userspace package i8kutils. 1269506f1d07SSam Ravnborg 1270039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1271039ae585SPali Rohár use userspace package i8kutils. 1272506f1d07SSam Ravnborg Say N otherwise. 1273506f1d07SSam Ravnborg 1274506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12759ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12769ba16087SJan Beulich depends on X86_32 1277506f1d07SSam Ravnborg ---help--- 1278506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1279506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1280506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1281506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1282506f1d07SSam Ravnborg system. 1283506f1d07SSam Ravnborg 1284506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12855e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1286506f1d07SSam Ravnborg 1287506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1288506f1d07SSam Ravnborg enable this option even if you don't need it. 1289506f1d07SSam Ravnborg Say N otherwise. 1290506f1d07SSam Ravnborg 1291506f1d07SSam Ravnborgconfig MICROCODE 12929a2bc335SBorislav Petkov bool "CPU microcode loading support" 12939a2bc335SBorislav Petkov default y 129480030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1295506f1d07SSam Ravnborg select FW_LOADER 1296506f1d07SSam Ravnborg ---help--- 1297506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12985f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12995f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 13005f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 13015f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 13025f9c01aaSBorislav Petkov the Linux kernel. 1303506f1d07SSam Ravnborg 13045f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 13051897a969SJaak Ristioja in Documentation/x86/microcode.txt. For that you need to enable 13065f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 13075f9c01aaSBorislav Petkov initrd for microcode blobs. 1308506f1d07SSam Ravnborg 1309c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1310c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1311c508c46eSBenjamin Gilbert config option. 1312506f1d07SSam Ravnborg 13138d86f390SPeter Orubaconfig MICROCODE_INTEL 1314e43f6e67SBorislav Petkov bool "Intel microcode loading support" 13158d86f390SPeter Oruba depends on MICROCODE 13168d86f390SPeter Oruba default MICROCODE 13178d86f390SPeter Oruba select FW_LOADER 13188f9ca475SIngo Molnar ---help--- 13198d86f390SPeter Oruba This options enables microcode patch loading support for Intel 13208d86f390SPeter Oruba processors. 13218d86f390SPeter Oruba 1322b8989db9SAlan For the current Intel microcode data package go to 1323b8989db9SAlan <https://downloadcenter.intel.com> and search for 1324b8989db9SAlan 'Linux Processor Microcode Data File'. 13258d86f390SPeter Oruba 132680cc9f10SPeter Orubaconfig MICROCODE_AMD 1327e43f6e67SBorislav Petkov bool "AMD microcode loading support" 132880cc9f10SPeter Oruba depends on MICROCODE 132980cc9f10SPeter Oruba select FW_LOADER 13308f9ca475SIngo Molnar ---help--- 133180cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 133280cc9f10SPeter Oruba processors will be enabled. 133380cc9f10SPeter Oruba 1334506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 13353c2362e6SHarvey Harrison def_bool y 1336506f1d07SSam Ravnborg depends on MICROCODE 1337506f1d07SSam Ravnborg 1338506f1d07SSam Ravnborgconfig X86_MSR 1339506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13408f9ca475SIngo Molnar ---help--- 1341506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1342506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1343506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1344506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1345506f1d07SSam Ravnborg systems. 1346506f1d07SSam Ravnborg 1347506f1d07SSam Ravnborgconfig X86_CPUID 1348506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13498f9ca475SIngo Molnar ---help--- 1350506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1351506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1352506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1353506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1354506f1d07SSam Ravnborg 1355506f1d07SSam Ravnborgchoice 1356506f1d07SSam Ravnborg prompt "High Memory Support" 13576fc108a0SJan Beulich default HIGHMEM4G 1358506f1d07SSam Ravnborg depends on X86_32 1359506f1d07SSam Ravnborg 1360506f1d07SSam Ravnborgconfig NOHIGHMEM 1361506f1d07SSam Ravnborg bool "off" 1362506f1d07SSam Ravnborg ---help--- 1363506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1364506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1365506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1366506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1367506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1368506f1d07SSam Ravnborg "high memory". 1369506f1d07SSam Ravnborg 1370506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1371506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1372506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1373506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1374506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1375506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1376506f1d07SSam Ravnborg possible. 1377506f1d07SSam Ravnborg 1378506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1379506f1d07SSam Ravnborg answer "4GB" here. 1380506f1d07SSam Ravnborg 1381506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1382506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1383506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1384506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1385506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1386506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1387506f1d07SSam Ravnborg 1388506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1389506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1390506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1391506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1392506f1d07SSam Ravnborg kernel at boot time.) 1393506f1d07SSam Ravnborg 1394506f1d07SSam Ravnborg If unsure, say "off". 1395506f1d07SSam Ravnborg 1396506f1d07SSam Ravnborgconfig HIGHMEM4G 1397506f1d07SSam Ravnborg bool "4GB" 13988f9ca475SIngo Molnar ---help--- 1399506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1400506f1d07SSam Ravnborg gigabytes of physical RAM. 1401506f1d07SSam Ravnborg 1402506f1d07SSam Ravnborgconfig HIGHMEM64G 1403506f1d07SSam Ravnborg bool "64GB" 140469b8d3fcSMatthew Whitehead depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1405506f1d07SSam Ravnborg select X86_PAE 14068f9ca475SIngo Molnar ---help--- 1407506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1408506f1d07SSam Ravnborg gigabytes of physical RAM. 1409506f1d07SSam Ravnborg 1410506f1d07SSam Ravnborgendchoice 1411506f1d07SSam Ravnborg 1412506f1d07SSam Ravnborgchoice 14136a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1414506f1d07SSam Ravnborg default VMSPLIT_3G 1415506f1d07SSam Ravnborg depends on X86_32 14168f9ca475SIngo Molnar ---help--- 1417506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1418506f1d07SSam Ravnborg 1419506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1420506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1421506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1422506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1423506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1424506f1d07SSam Ravnborg available to user programs, making the address space there 1425506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1426506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1427506f1d07SSam Ravnborg kernel modules. 1428506f1d07SSam Ravnborg 1429506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1430506f1d07SSam Ravnborg option alone! 1431506f1d07SSam Ravnborg 1432506f1d07SSam Ravnborg config VMSPLIT_3G 1433506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1434506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1435506f1d07SSam Ravnborg depends on !X86_PAE 1436506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1437506f1d07SSam Ravnborg config VMSPLIT_2G 1438506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1439506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1440506f1d07SSam Ravnborg depends on !X86_PAE 1441506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1442506f1d07SSam Ravnborg config VMSPLIT_1G 1443506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1444506f1d07SSam Ravnborgendchoice 1445506f1d07SSam Ravnborg 1446506f1d07SSam Ravnborgconfig PAGE_OFFSET 1447506f1d07SSam Ravnborg hex 1448506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1449506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1450506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1451506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1452506f1d07SSam Ravnborg default 0xC0000000 1453506f1d07SSam Ravnborg depends on X86_32 1454506f1d07SSam Ravnborg 1455506f1d07SSam Ravnborgconfig HIGHMEM 14563c2362e6SHarvey Harrison def_bool y 1457506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1458506f1d07SSam Ravnborg 1459506f1d07SSam Ravnborgconfig X86_PAE 14609ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1461506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 14629d99c712SChristian Melki select SWIOTLB 14638f9ca475SIngo Molnar ---help--- 1464506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1465506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1466506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1467506f1d07SSam Ravnborg consumes more pagetable space per process. 1468506f1d07SSam Ravnborg 146977ef56e4SKirill A. Shutemovconfig X86_5LEVEL 147077ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 1471eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 1472162434e7SKirill A. Shutemov select SPARSEMEM_VMEMMAP 147377ef56e4SKirill A. Shutemov depends on X86_64 147477ef56e4SKirill A. Shutemov ---help--- 147577ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 147677ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 147777ef56e4SKirill A. Shutemov physical address space. 147877ef56e4SKirill A. Shutemov 147977ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 148077ef56e4SKirill A. Shutemov 14816657fca0SKirill A. Shutemov A kernel with the option enabled can be booted on machines that 14826657fca0SKirill A. Shutemov support 4- or 5-level paging. 148377ef56e4SKirill A. Shutemov 148477ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 148577ef56e4SKirill A. Shutemov information. 148677ef56e4SKirill A. Shutemov 148777ef56e4SKirill A. Shutemov Say N if unsure. 148877ef56e4SKirill A. Shutemov 1489600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 14903120e25eSJan Beulich def_bool y 14913120e25eSJan Beulich depends on X86_64 || X86_PAE 1492600715dcSJeremy Fitzhardinge 149366f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 14943120e25eSJan Beulich def_bool y 14953120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 149666f2b061SFUJITA Tomonori 149710971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1498e5008abeSLuis R. Rodriguez def_bool y 14994675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 15008f9ca475SIngo Molnar ---help--- 150110971ab2SIngo Molnar Certain kernel features effectively disable kernel 150210971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 150310971ab2SIngo Molnar supports them), so don't confuse the user by printing 150410971ab2SIngo Molnar that we have them enabled. 15059e899816SNick Piggin 15067744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 15077744ccdbSTom Lendacky def_bool y 15087744ccdbSTom Lendacky 15097744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 15107744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 15117744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 15127744ccdbSTom Lendacky ---help--- 15137744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 15147744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 15157744ccdbSTom Lendacky Encryption (SME). 15167744ccdbSTom Lendacky 15177744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 15187744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 15197744ccdbSTom Lendacky default y 15207744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 15217744ccdbSTom Lendacky ---help--- 15227744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 15237744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 15247744ccdbSTom Lendacky 15257744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 15267744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 15277744ccdbSTom Lendacky 15287744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 15297744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 15307744ccdbSTom Lendacky 1531f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1532f88a68faSTom Lendacky def_bool y 1533f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1534f88a68faSTom Lendacky 1535506f1d07SSam Ravnborg# Common NUMA Features 1536506f1d07SSam Ravnborgconfig NUMA 1537fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1538506f1d07SSam Ravnborg depends on SMP 1539b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1540b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15418f9ca475SIngo Molnar ---help--- 1542506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1543fd51b2d7SKOSAKI Motohiro 1544506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1545506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1546506f1d07SSam Ravnborg NUMA awareness to the kernel. 1547506f1d07SSam Ravnborg 1548c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1549fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1550fd51b2d7SKOSAKI Motohiro 1551b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15527cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1553fd51b2d7SKOSAKI Motohiro 1554fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1555506f1d07SSam Ravnborg 1556eec1d4faSHans Rosenfeldconfig AMD_NUMA 15573c2362e6SHarvey Harrison def_bool y 15583c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15595da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15608f9ca475SIngo Molnar ---help--- 1561eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1562eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1563eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1564eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1565eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1566506f1d07SSam Ravnborg 1567506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15683c2362e6SHarvey Harrison def_bool y 15693c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1570506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1571506f1d07SSam Ravnborg select ACPI_NUMA 15728f9ca475SIngo Molnar ---help--- 1573506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1574506f1d07SSam Ravnborg 15756ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15766ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15776ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15786ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15796ec6e0d9SSuresh Siddha# for details. 15806ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15816ec6e0d9SSuresh Siddha def_bool y 15826ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15836ec6e0d9SSuresh Siddha 1584506f1d07SSam Ravnborgconfig NUMA_EMU 1585506f1d07SSam Ravnborg bool "NUMA emulation" 15861b7e03efSTejun Heo depends on NUMA 15878f9ca475SIngo Molnar ---help--- 1588506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1589506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1590506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1591506f1d07SSam Ravnborg 1592506f1d07SSam Ravnborgconfig NODES_SHIFT 1593d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 159451591e31SDavid Rientjes range 1 10 159551591e31SDavid Rientjes default "10" if MAXSMP 1596506f1d07SSam Ravnborg default "6" if X86_64 1597506f1d07SSam Ravnborg default "3" 1598506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15998f9ca475SIngo Molnar ---help--- 16001184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1601692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1602506f1d07SSam Ravnborg 1603506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 16043c2362e6SHarvey Harrison def_bool y 1605506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1606506f1d07SSam Ravnborg 1607506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1608506f1d07SSam Ravnborg def_bool y 16093b16651fSTejun Heo depends on X86_32 && !NUMA 1610506f1d07SSam Ravnborg 1611506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1612506f1d07SSam Ravnborg def_bool y 1613b263295dSChristoph Lameter depends on NUMA && X86_32 1614506f1d07SSam Ravnborg 1615506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1616506f1d07SSam Ravnborg def_bool y 1617b263295dSChristoph Lameter depends on NUMA && X86_32 1618b263295dSChristoph Lameter 1619506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1620506f1d07SSam Ravnborg def_bool y 16216ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1622506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1623506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1624506f1d07SSam Ravnborg 16253b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 16263b16651fSTejun Heo def_bool y 16273b16651fSTejun Heo depends on X86_64 16283b16651fSTejun Heo 1629506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1630506f1d07SSam Ravnborg def_bool y 1631b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1632506f1d07SSam Ravnborg 1633506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1634a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16353120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1636a0842b70SToshi Kani help 1637a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1638a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1639a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1640506f1d07SSam Ravnborg 16413b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16423b16651fSTejun Heo def_bool y 16433b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16443b16651fSTejun Heo 1645a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1646a29815a3SAvi Kivity hex 1647a29815a3SAvi Kivity default 0 if X86_32 1648a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1649a29815a3SAvi Kivity 1650506f1d07SSam Ravnborgsource "mm/Kconfig" 1651506f1d07SSam Ravnborg 16527a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16537a67832cSDan Williams bool 16547a67832cSDan Williams 1655ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16567a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16579f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16589f53f9faSDan Williams depends on BLK_DEV 16597a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16609f53f9faSDan Williams select LIBNVDIMM 1661ec776ef6SChristoph Hellwig help 1662ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1663ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1664ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1665ec776ef6SChristoph Hellwig they can be used for persistent storage. 1666ec776ef6SChristoph Hellwig 1667ec776ef6SChristoph Hellwig Say Y if unsure. 1668ec776ef6SChristoph Hellwig 1669506f1d07SSam Ravnborgconfig HIGHPTE 1670506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16716fc108a0SJan Beulich depends on HIGHMEM 16728f9ca475SIngo Molnar ---help--- 1673506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1674506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1675506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1676506f1d07SSam Ravnborg entries in high memory. 1677506f1d07SSam Ravnborg 16789f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16799f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16808f9ca475SIngo Molnar ---help--- 16819f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16829f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16839f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16849f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16859f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16869f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16879f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16888c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16899f077871SJeremy Fitzhardinge 16909f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16919f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16929f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16939f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16949f077871SJeremy Fitzhardinge 16959f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16969f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16979f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16989f077871SJeremy Fitzhardinge memory. 16999f077871SJeremy Fitzhardinge 1700c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1701c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1702c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1703c885df50SJeremy Fitzhardinge default y 17048f9ca475SIngo Molnar ---help--- 1705c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1706c885df50SJeremy Fitzhardinge on or off. 1707c885df50SJeremy Fitzhardinge 17089ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1709d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1710d0cd7425SH. Peter Anvin default 64 1711d0cd7425SH. Peter Anvin range 4 640 17128f9ca475SIngo Molnar ---help--- 1713d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1714fc381519SIngo Molnar 1715d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1716d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1717fc381519SIngo Molnar 1718d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1719d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1720d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1721d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1722fc381519SIngo Molnar 1723d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1724d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1725d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1726d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1727d0cd7425SH. Peter Anvin entire low memory range. 1728d0cd7425SH. Peter Anvin 1729d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1730d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1731d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1732d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1733d0cd7425SH. Peter Anvin typical corruption patterns. 1734d0cd7425SH. Peter Anvin 1735d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1736fc381519SIngo Molnar 1737506f1d07SSam Ravnborgconfig MATH_EMULATION 1738506f1d07SSam Ravnborg bool 1739a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1740506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1741506f1d07SSam Ravnborg ---help--- 1742506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1743506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1744506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1745506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1746506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1747506f1d07SSam Ravnborg coprocessor or this emulation. 1748506f1d07SSam Ravnborg 1749506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1750506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1751506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1752506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1753506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1754506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1755506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1756506f1d07SSam Ravnborg intend to use this kernel on different machines. 1757506f1d07SSam Ravnborg 1758506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1759506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1760506f1d07SSam Ravnborg 1761506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1762506f1d07SSam Ravnborg kernel, it won't hurt. 1763506f1d07SSam Ravnborg 1764506f1d07SSam Ravnborgconfig MTRR 17656fc108a0SJan Beulich def_bool y 17666a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1767506f1d07SSam Ravnborg ---help--- 1768506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1769506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1770506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1771506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1772506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1773506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1774506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1775506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1776506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1777506f1d07SSam Ravnborg 1778506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1779506f1d07SSam Ravnborg control registers on other processors can be easily supported 1780506f1d07SSam Ravnborg as well: 1781506f1d07SSam Ravnborg 1782506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1783506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1784506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1785506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1786506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1787506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1788506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1789506f1d07SSam Ravnborg 1790506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1791506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1792506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1793506f1d07SSam Ravnborg 1794506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1795506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1796506f1d07SSam Ravnborg 17977225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1798506f1d07SSam Ravnborg 179995ffa243SYinghai Luconfig MTRR_SANITIZER 18002ffb3501SYinghai Lu def_bool y 180195ffa243SYinghai Lu prompt "MTRR cleanup support" 180295ffa243SYinghai Lu depends on MTRR 18038f9ca475SIngo Molnar ---help--- 1804aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1805aba3728cSThomas Gleixner add writeback entries. 180695ffa243SYinghai Lu 1807aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1808692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1809aba3728cSThomas Gleixner mtrr_chunk_size. 181095ffa243SYinghai Lu 18112ffb3501SYinghai Lu If unsure, say Y. 181295ffa243SYinghai Lu 181395ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1814f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1815f5098d62SYinghai Lu range 0 1 1816f5098d62SYinghai Lu default "0" 181795ffa243SYinghai Lu depends on MTRR_SANITIZER 18188f9ca475SIngo Molnar ---help--- 1819f5098d62SYinghai Lu Enable mtrr cleanup default value 182095ffa243SYinghai Lu 182112031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 182212031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 182312031a62SYinghai Lu range 0 7 182412031a62SYinghai Lu default "1" 182512031a62SYinghai Lu depends on MTRR_SANITIZER 18268f9ca475SIngo Molnar ---help--- 182712031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1828aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 182912031a62SYinghai Lu 18302e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 18316fc108a0SJan Beulich def_bool y 18326a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 18332a8a2719SIngo Molnar depends on MTRR 18348f9ca475SIngo Molnar ---help--- 18352e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1836042b78e4SVenki Pallipadi 18372e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18382e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18392e5d9c85Svenkatesh.pallipadi@intel.com 18402e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1841042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18422e5d9c85Svenkatesh.pallipadi@intel.com 18432e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18442e5d9c85Svenkatesh.pallipadi@intel.com 184546cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 184646cf98cdSVenkatesh Pallipadi def_bool y 184746cf98cdSVenkatesh Pallipadi depends on X86_PAT 184846cf98cdSVenkatesh Pallipadi 1849628c6246SH. Peter Anvinconfig ARCH_RANDOM 1850628c6246SH. Peter Anvin def_bool y 1851628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1852628c6246SH. Peter Anvin ---help--- 1853628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1854628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1855628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1856628c6246SH. Peter Anvin secure hardware random number generator. 1857628c6246SH. Peter Anvin 185851ae4a2dSH. Peter Anvinconfig X86_SMAP 185951ae4a2dSH. Peter Anvin def_bool y 186051ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 186151ae4a2dSH. Peter Anvin ---help--- 186251ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 186351ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 186451ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 186551ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 186651ae4a2dSH. Peter Anvin 186751ae4a2dSH. Peter Anvin If unsure, say Y. 186851ae4a2dSH. Peter Anvin 1869aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1870796ebc81SRicardo Neri def_bool y 1871aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1872aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1873aa35f896SRicardo Neri ---help--- 1874aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1875aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1876796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1877796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1878796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1879796ebc81SRicardo Neri 1880796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1881796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1882796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1883796ebc81SRicardo Neri results are dummy. 1884aa35f896SRicardo Neri 188572e9b5feSDave Hansenconfig X86_INTEL_MPX 188672e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 188772e9b5feSDave Hansen def_bool n 1888df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1889df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1890df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 189172e9b5feSDave Hansen ---help--- 189272e9b5feSDave Hansen MPX provides hardware features that can be used in 189372e9b5feSDave Hansen conjunction with compiler-instrumented code to check 189472e9b5feSDave Hansen memory references. It is designed to detect buffer 189572e9b5feSDave Hansen overflow or underflow bugs. 189672e9b5feSDave Hansen 189772e9b5feSDave Hansen This option enables running applications which are 189872e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 189972e9b5feSDave Hansen itself inside the kernel or to protect the kernel 190072e9b5feSDave Hansen against bad memory references. 190172e9b5feSDave Hansen 190272e9b5feSDave Hansen Enabling this option will make the kernel larger: 190372e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 190472e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 190572e9b5feSDave Hansen will increase the kernel memory overhead of each 190672e9b5feSDave Hansen process and adds some branches to paths used during 190772e9b5feSDave Hansen exec() and munmap(). 190872e9b5feSDave Hansen 190972e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 191072e9b5feSDave Hansen 191172e9b5feSDave Hansen If unsure, say N. 191272e9b5feSDave Hansen 191335e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1914284244a9SDave Hansen prompt "Intel Memory Protection Keys" 191535e97790SDave Hansen def_bool y 1916284244a9SDave Hansen # Note: only available in 64-bit mode 191735e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 191852c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 191952c8e601SIngo Molnar select ARCH_HAS_PKEYS 1920284244a9SDave Hansen ---help--- 1921284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1922284244a9SDave Hansen page-based protections, but without requiring modification of the 1923284244a9SDave Hansen page tables when an application changes protection domains. 1924284244a9SDave Hansen 1925284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1926284244a9SDave Hansen 1927284244a9SDave Hansen If unsure, say y. 192835e97790SDave Hansen 1929506f1d07SSam Ravnborgconfig EFI 19309ba16087SJan Beulich bool "EFI runtime service support" 19315b83683fSHuang, Ying depends on ACPI 1932f6ce5002SSergey Vlasov select UCS2_STRING 1933022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1934506f1d07SSam Ravnborg ---help--- 19358b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1936506f1d07SSam Ravnborg available (such as the EFI variable services). 1937506f1d07SSam Ravnborg 19388b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19398b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19408b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19418b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19428b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19438b2cb7a8SHuang, Ying platforms. 1944506f1d07SSam Ravnborg 1945291f3632SMatt Flemingconfig EFI_STUB 1946291f3632SMatt Fleming bool "EFI stub support" 1947b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19487b2a583aSMatt Fleming select RELOCATABLE 1949291f3632SMatt Fleming ---help--- 1950291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1951291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1952291f3632SMatt Fleming 19534172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19540c759662SMatt Fleming 19557d453eeeSMatt Flemingconfig EFI_MIXED 19567d453eeeSMatt Fleming bool "EFI mixed-mode support" 19577d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19587d453eeeSMatt Fleming ---help--- 19597d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19607d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19617d453eeeSMatt Fleming mode. 19627d453eeeSMatt Fleming 19637d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19647d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19657d453eeeSMatt Fleming the EFI handover protocol must be used. 19667d453eeeSMatt Fleming 19677d453eeeSMatt Fleming If unsure, say N. 19687d453eeeSMatt Fleming 1969506f1d07SSam Ravnborgconfig SECCOMP 19703c2362e6SHarvey Harrison def_bool y 19713c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19728f9ca475SIngo Molnar ---help--- 1973506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1974506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1975506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1976506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1977506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1978506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19799c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1980506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1981506f1d07SSam Ravnborg defined by each seccomp mode. 1982506f1d07SSam Ravnborg 1983506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1984506f1d07SSam Ravnborg 1985506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1986506f1d07SSam Ravnborg 1987506f1d07SSam Ravnborgconfig KEXEC 1988506f1d07SSam Ravnborg bool "kexec system call" 19892965faa5SDave Young select KEXEC_CORE 19908f9ca475SIngo Molnar ---help--- 1991506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1992506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1993506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1994506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1995506f1d07SSam Ravnborg 1996506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1997506f1d07SSam Ravnborg 1998506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1999506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 2000bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 2001bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 2002bf220695SGeert Uytterhoeven made. 2003506f1d07SSam Ravnborg 200474ca317cSVivek Goyalconfig KEXEC_FILE 200574ca317cSVivek Goyal bool "kexec file based system call" 20062965faa5SDave Young select KEXEC_CORE 200774ca317cSVivek Goyal select BUILD_BIN2C 200874ca317cSVivek Goyal depends on X86_64 200974ca317cSVivek Goyal depends on CRYPTO=y 201074ca317cSVivek Goyal depends on CRYPTO_SHA256=y 201174ca317cSVivek Goyal ---help--- 201274ca317cSVivek Goyal This is new version of kexec system call. This system call is 201374ca317cSVivek Goyal file based and takes file descriptors as system call argument 201474ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 201574ca317cSVivek Goyal accepted by previous system call. 201674ca317cSVivek Goyal 2017b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY 2018b799a09fSAKASHI Takahiro def_bool KEXEC_FILE 2019b799a09fSAKASHI Takahiro 20208e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 20218e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 202274ca317cSVivek Goyal depends on KEXEC_FILE 20238e7d8381SVivek Goyal ---help--- 20248e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 2025d8eb8940SBorislav Petkov the kexec_file_load() syscall. 20268e7d8381SVivek Goyal 2027d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 2028d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 2029d8eb8940SBorislav Petkov loaded in order for this to work. 20308e7d8381SVivek Goyal 20318e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 20328e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 20338e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 20348e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 20358e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 20368e7d8381SVivek Goyal ---help--- 20378e7d8381SVivek Goyal Enable bzImage signature verification support. 20388e7d8381SVivek Goyal 2039506f1d07SSam Ravnborgconfig CRASH_DUMP 204004b69447SPavel Machek bool "kernel crash dumps" 2041506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20428f9ca475SIngo Molnar ---help--- 2043506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2044506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2045506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2046506f1d07SSam Ravnborg a specially reserved region and then later executed after 2047506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2048506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2049506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2050506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2051506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2052506f1d07SSam Ravnborg 20533ab83521SHuang Yingconfig KEXEC_JUMP 20546ea30386SKees Cook bool "kexec jump" 2055fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20568f9ca475SIngo Molnar ---help--- 205789081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 205889081d17SHuang Ying code in physical address mode via KEXEC 20593ab83521SHuang Ying 2060506f1d07SSam Ravnborgconfig PHYSICAL_START 20616a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2062ceefccc9SH. Peter Anvin default "0x1000000" 20638f9ca475SIngo Molnar ---help--- 2064506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2065506f1d07SSam Ravnborg 2066506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2067506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2068506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2069506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2070506f1d07SSam Ravnborg address. 2071506f1d07SSam Ravnborg 2072506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2073506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2074506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2075506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2076506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2077506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2078506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2079506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2080506f1d07SSam Ravnborg 2081ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2082ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2083ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2084ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2085ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2086ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2087ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2088ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2089ceefccc9SH. Peter Anvin for more details about crash dumps. 2090506f1d07SSam Ravnborg 2091506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2092506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2093506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2094506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2095506f1d07SSam Ravnborg is present because there are users out there who continue to use 2096506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2097506f1d07SSam Ravnborg line. 2098506f1d07SSam Ravnborg 2099506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2100506f1d07SSam Ravnborg 2101506f1d07SSam Ravnborgconfig RELOCATABLE 210226717808SH. Peter Anvin bool "Build a relocatable kernel" 210326717808SH. Peter Anvin default y 21048f9ca475SIngo Molnar ---help--- 2105506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2106506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2107506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2108506f1d07SSam Ravnborg but are discarded at runtime. 2109506f1d07SSam Ravnborg 2110506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2111506f1d07SSam Ravnborg must live at a different physical address than the primary 2112506f1d07SSam Ravnborg kernel. 2113506f1d07SSam Ravnborg 2114506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2115506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 21168ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2117506f1d07SSam Ravnborg 21188ab3820fSKees Cookconfig RANDOMIZE_BASE 2119e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 21208ab3820fSKees Cook depends on RELOCATABLE 21216807c846SIngo Molnar default y 21228ab3820fSKees Cook ---help--- 2123e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2124e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2125e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2126e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2127e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2128e8581e3dSBaoquan He code internals. 2129e8581e3dSBaoquan He 2130ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2131ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2132ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2133ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2134ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2135ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2136ed9f007eSKees Cook 2137ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2138ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2139ed9f007eSKees Cook 512MB (8 bits of entropy). 21408ab3820fSKees Cook 2141a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2142e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2143e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2144ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2145ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2146ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2147ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2148ed9f007eSKees Cook theoretically possible, but the implementations are further 2149ed9f007eSKees Cook limited due to memory layouts. 2150e8581e3dSBaoquan He 21516807c846SIngo Molnar If unsure, say Y. 2152da2b6fb9SKees Cook 21538ab3820fSKees Cook# Relocation on x86 needs some additional build support 2154845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2155845adf72SH. Peter Anvin def_bool y 21568ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2157845adf72SH. Peter Anvin 2158506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2159a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21608ab3820fSKees Cook default "0x200000" 2161a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2162a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21638f9ca475SIngo Molnar ---help--- 2164506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2165506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2166506f1d07SSam Ravnborg address which meets above alignment restriction. 2167506f1d07SSam Ravnborg 2168506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2169506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2170506f1d07SSam Ravnborg address aligned to above value and run from there. 2171506f1d07SSam Ravnborg 2172506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2173506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2174506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2175506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2176506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2177506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2178506f1d07SSam Ravnborg above alignment restrictions. 2179506f1d07SSam Ravnborg 2180a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2181a0215061SKees Cook this value must be a multiple of 0x200000. 2182a0215061SKees Cook 2183506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2184506f1d07SSam Ravnborg 2185eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT 2186eedb92abSKirill A. Shutemov bool 2187eedb92abSKirill A. Shutemov ---help--- 2188eedb92abSKirill A. Shutemov This option makes base addresses of vmalloc and vmemmap as well as 2189eedb92abSKirill A. Shutemov __PAGE_OFFSET movable during boot. 2190eedb92abSKirill A. Shutemov 21910483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21920483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21930483e1faSThomas Garnier depends on X86_64 21940483e1faSThomas Garnier depends on RANDOMIZE_BASE 2195eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 21960483e1faSThomas Garnier default RANDOMIZE_BASE 21970483e1faSThomas Garnier ---help--- 21980483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21990483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 22000483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 22010483e1faSThomas Garnier 22020483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 22030483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 22040483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 22050483e1faSThomas Garnier addresses for each memory section. 22060483e1faSThomas Garnier 22076807c846SIngo Molnar If unsure, say Y. 22080483e1faSThomas Garnier 220990397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 221090397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 221190397a41SThomas Garnier depends on RANDOMIZE_MEMORY 221290397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 221390397a41SThomas Garnier default "0x0" 221490397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 221590397a41SThomas Garnier range 0x0 0x40 221690397a41SThomas Garnier ---help--- 221790397a41SThomas Garnier Define the padding in terabytes added to the existing physical 221890397a41SThomas Garnier memory size during kernel memory randomization. It is useful 221990397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 222090397a41SThomas Garnier address randomization. 222190397a41SThomas Garnier 222290397a41SThomas Garnier If unsure, leave at the default value. 222390397a41SThomas Garnier 2224506f1d07SSam Ravnborgconfig HOTPLUG_CPU 22257c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 222640b31360SStephen Rothwell depends on SMP 2227506f1d07SSam Ravnborg ---help--- 22287c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 22297c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 22307c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 22317c13e6a3SDimitri Sivanich automatically on SMP systems. ) 22327c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2233506f1d07SSam Ravnborg 223480aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 223580aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 223680aa1dffSFenghua Yu default n 22372c922cd0SKees Cook depends on HOTPLUG_CPU 223880aa1dffSFenghua Yu ---help--- 223980aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 224080aa1dffSFenghua Yu 224180aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 224280aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 224380aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 224480aa1dffSFenghua Yu 224580aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 224680aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 224780aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 224880aa1dffSFenghua Yu 224980aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 225080aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 225180aa1dffSFenghua Yu 225280aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 225380aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 225480aa1dffSFenghua Yu be other CPU0 dependencies. 225580aa1dffSFenghua Yu 225680aa1dffSFenghua Yu Please make sure the dependencies are under your control before 225780aa1dffSFenghua Yu you enable this feature. 225880aa1dffSFenghua Yu 225980aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 226080aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 226180aa1dffSFenghua Yu parameter cpu0_hotplug. 226280aa1dffSFenghua Yu 2263a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2264a71c8bc5SFenghua Yu def_bool n 2265a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 22662c922cd0SKees Cook depends on HOTPLUG_CPU 2267a71c8bc5SFenghua Yu ---help--- 2268a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2269a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2270a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2271a71c8bc5SFenghua Yu 2272a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2273a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2274a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2275a71c8bc5SFenghua Yu 2276a71c8bc5SFenghua Yu If unsure, say N. 2277a71c8bc5SFenghua Yu 2278506f1d07SSam Ravnborgconfig COMPAT_VDSO 2279b0b49f26SAndy Lutomirski def_bool n 2280b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2281953fee1dSIngo Molnar depends on COMPAT_32 22828f9ca475SIngo Molnar ---help--- 2283b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2284b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2285b0b49f26SAndy Lutomirski indicated in its segment table. 2286e84446deSRandy Dunlap 2287b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2288b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2289b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2290b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2291b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2292506f1d07SSam Ravnborg 2293b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2294b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2295b0b49f26SAndy Lutomirski 2296b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2297b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2298b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2299b0b49f26SAndy Lutomirski 2300b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2301b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2302506f1d07SSam Ravnborg 23033dc33bd3SKees Cookchoice 23043dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 23053dc33bd3SKees Cook depends on X86_64 23063dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 23073dc33bd3SKees Cook help 23083dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 23093dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 23103dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 23113dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 23123dc33bd3SKees Cook 23133dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 2314076ca272SAndy Lutomirski line parameter vsyscall=[emulate|none]. 23153dc33bd3SKees Cook 23163dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 23173dc33bd3SKees Cook static binaries, you can say None without a performance penalty 23183dc33bd3SKees Cook to improve security. 23193dc33bd3SKees Cook 23203dc33bd3SKees Cook If unsure, select "Emulate". 23213dc33bd3SKees Cook 23223dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 23233dc33bd3SKees Cook bool "Emulate" 23243dc33bd3SKees Cook help 23253dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 23263dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 23273dc33bd3SKees Cook non-executable, but it still contains known contents, 23283dc33bd3SKees Cook which could be used in certain rare security vulnerability 23293dc33bd3SKees Cook exploits. This configuration is recommended when userspace 23303dc33bd3SKees Cook still uses the vsyscall area. 23313dc33bd3SKees Cook 23323dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 23333dc33bd3SKees Cook bool "None" 23343dc33bd3SKees Cook help 23353dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 23363dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 23373dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 23383dc33bd3SKees Cook will be reported to dmesg, so that either old or 23393dc33bd3SKees Cook malicious userspace programs can be identified. 23403dc33bd3SKees Cook 23413dc33bd3SKees Cookendchoice 23423dc33bd3SKees Cook 2343516cbf37STim Birdconfig CMDLINE_BOOL 2344516cbf37STim Bird bool "Built-in kernel command line" 23458f9ca475SIngo Molnar ---help--- 2346516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2347516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2348516cbf37STim Bird necessary or convenient to provide some or all of the 2349516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2350516cbf37STim Bird to not rely on the boot loader to provide them.) 2351516cbf37STim Bird 2352516cbf37STim Bird To compile command line arguments into the kernel, 2353516cbf37STim Bird set this option to 'Y', then fill in the 235469711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2355516cbf37STim Bird 2356516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2357516cbf37STim Bird should leave this option set to 'N'. 2358516cbf37STim Bird 2359516cbf37STim Birdconfig CMDLINE 2360516cbf37STim Bird string "Built-in kernel command string" 2361516cbf37STim Bird depends on CMDLINE_BOOL 2362516cbf37STim Bird default "" 23638f9ca475SIngo Molnar ---help--- 2364516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2365516cbf37STim Bird image and used at boot time. If the boot loader provides a 2366516cbf37STim Bird command line at boot time, it is appended to this string to 2367516cbf37STim Bird form the full kernel command line, when the system boots. 2368516cbf37STim Bird 2369516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2370516cbf37STim Bird change this behavior. 2371516cbf37STim Bird 2372516cbf37STim Bird In most cases, the command line (whether built-in or provided 2373516cbf37STim Bird by the boot loader) should specify the device for the root 2374516cbf37STim Bird file system. 2375516cbf37STim Bird 2376516cbf37STim Birdconfig CMDLINE_OVERRIDE 2377516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2378516cbf37STim Bird depends on CMDLINE_BOOL 23798f9ca475SIngo Molnar ---help--- 2380516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2381516cbf37STim Bird command line, and use ONLY the built-in command line. 2382516cbf37STim Bird 2383516cbf37STim Bird This is used to work around broken boot loaders. This should 2384516cbf37STim Bird be set to 'N' under normal conditions. 2385516cbf37STim Bird 2386a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2387a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2388a5b9e5a2SAndy Lutomirski default y 2389a5b9e5a2SAndy Lutomirski ---help--- 2390a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2391a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2392a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2393a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2394a5b9e5a2SAndy Lutomirski threading libraries. 2395a5b9e5a2SAndy Lutomirski 2396a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2397a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2398a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2399a5b9e5a2SAndy Lutomirski 2400a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2401a5b9e5a2SAndy Lutomirski 2402b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2403b700e7f0SSeth Jennings 2404506f1d07SSam Ravnborgendmenu 2405506f1d07SSam Ravnborg 24063072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 24073072e413SMichal Hocko def_bool y 24083072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 24093072e413SMichal Hocko 2410506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2411506f1d07SSam Ravnborg def_bool y 2412506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2413506f1d07SSam Ravnborg 241435551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 241535551053SGary Hade def_bool y 241635551053SGary Hade depends on MEMORY_HOTPLUG 241735551053SGary Hade 2418e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2419645a7919STejun Heo def_bool y 2420e534c7c5SLee Schermerhorn depends on NUMA 2421e534c7c5SLee Schermerhorn 24229491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 24239491846fSKirill A. Shutemov def_bool y 24249491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 24259491846fSKirill A. Shutemov 2426c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2427c177c81eSNaoya Horiguchi def_bool y 2428c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2429c177c81eSNaoya Horiguchi 24309c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 24319c670ea3SNaoya Horiguchi def_bool y 24329c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 24339c670ea3SNaoya Horiguchi 2434da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2435e279b6c1SSam Ravnborg 2436e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 24373c2362e6SHarvey Harrison def_bool y 2438e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2439e279b6c1SSam Ravnborg 2440e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2441e279b6c1SSam Ravnborg 2442e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2443e279b6c1SSam Ravnborg 2444efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2445efafc8b2SFeng Tang 2446a6b68076SAndi Kleenconfig X86_APM_BOOT 24476fc108a0SJan Beulich def_bool y 2448282e5aabSPaul Bolle depends on APM 2449a6b68076SAndi Kleen 2450e279b6c1SSam Ravnborgmenuconfig APM 2451e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2452efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2453e279b6c1SSam Ravnborg ---help--- 2454e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2455e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2456e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2457e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2458e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2459e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2460e279b6c1SSam Ravnborg 2461e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2462e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2463e279b6c1SSam Ravnborg 2464e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2465e279b6c1SSam Ravnborg machines with more than one CPU. 2466e279b6c1SSam Ravnborg 2467e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 24682dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 24692dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2470e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2471e279b6c1SSam Ravnborg 2472e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2473e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2474e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2475e279b6c1SSam Ravnborg 2476e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2477e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2478e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2479e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2480e279b6c1SSam Ravnborg 2481e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2482e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2483e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2484e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2485e279b6c1SSam Ravnborg APM in your BIOS). 2486e279b6c1SSam Ravnborg 2487e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2488e279b6c1SSam Ravnborg "weird" problems: 2489e279b6c1SSam Ravnborg 2490e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2491e279b6c1SSam Ravnborg enabled. 2492e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2493e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2494e279b6c1SSam Ravnborg the "no387" option to the kernel 2495e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2496e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2497e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2498e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2499e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2500e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2501e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2502e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2503e279b6c1SSam Ravnborg 11) exchange RAM chips 2504e279b6c1SSam Ravnborg 12) exchange the motherboard. 2505e279b6c1SSam Ravnborg 2506e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2507e279b6c1SSam Ravnborg module will be called apm. 2508e279b6c1SSam Ravnborg 2509e279b6c1SSam Ravnborgif APM 2510e279b6c1SSam Ravnborg 2511e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2512e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 25138f9ca475SIngo Molnar ---help--- 2514e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2515e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2516e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2517e279b6c1SSam Ravnborg 2518e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2519e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2520e279b6c1SSam Ravnborg ---help--- 2521e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2522e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2523e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2524e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2525e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2526e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2527e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2528e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2529e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2530e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2531e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2532e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2533e279b6c1SSam Ravnborg this feature. 2534e279b6c1SSam Ravnborg 2535e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2536dd8af076SLen Brown depends on CPU_IDLE 2537e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 25388f9ca475SIngo Molnar ---help--- 2539e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2540e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2541e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2542e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2543e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2544e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2545e279b6c1SSam Ravnborg this option does nothing.) 2546e279b6c1SSam Ravnborg 2547e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2548e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 25498f9ca475SIngo Molnar ---help--- 2550e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2551e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2552e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2553e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2554e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2555e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2556e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2557e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2558e279b6c1SSam Ravnborg especially if you are using gpm. 2559e279b6c1SSam Ravnborg 2560e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2561e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 25628f9ca475SIngo Molnar ---help--- 2563e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2564e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2565e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2566e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2567e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2568e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2569e279b6c1SSam Ravnborg 2570e279b6c1SSam Ravnborgendif # APM 2571e279b6c1SSam Ravnborg 2572bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2573e279b6c1SSam Ravnborg 2574e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2575e279b6c1SSam Ravnborg 257627471fdbSAndy Henroidsource "drivers/idle/Kconfig" 257727471fdbSAndy Henroid 2578e279b6c1SSam Ravnborgendmenu 2579e279b6c1SSam Ravnborg 2580e279b6c1SSam Ravnborg 2581e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2582e279b6c1SSam Ravnborg 2583e279b6c1SSam Ravnborgconfig PCI 25841ac97018SIngo Molnar bool "PCI support" 25851c858087SAdrian Bunk default y 25868f9ca475SIngo Molnar ---help--- 2587e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2588e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2589e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2590e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2591e279b6c1SSam Ravnborg 2592e279b6c1SSam Ravnborgchoice 2593e279b6c1SSam Ravnborg prompt "PCI access mode" 2594efefa6f6SIngo Molnar depends on X86_32 && PCI 2595e279b6c1SSam Ravnborg default PCI_GOANY 2596e279b6c1SSam Ravnborg ---help--- 2597e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2598e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2599e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2600e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2601e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2602e279b6c1SSam Ravnborg 2603e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2604e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2605e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2606e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2607e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2608e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2609e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2610e279b6c1SSam Ravnborg 2611e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2612e279b6c1SSam Ravnborg bool "BIOS" 2613e279b6c1SSam Ravnborg 2614e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2615e279b6c1SSam Ravnborg bool "MMConfig" 2616e279b6c1SSam Ravnborg 2617e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2618e279b6c1SSam Ravnborg bool "Direct" 2619e279b6c1SSam Ravnborg 26203ef0e1f8SAndres Salomonconfig PCI_GOOLPC 262176fb6570SDaniel Drake bool "OLPC XO-1" 26223ef0e1f8SAndres Salomon depends on OLPC 26233ef0e1f8SAndres Salomon 26242bdd1b03SAndres Salomonconfig PCI_GOANY 26252bdd1b03SAndres Salomon bool "Any" 26262bdd1b03SAndres Salomon 2627e279b6c1SSam Ravnborgendchoice 2628e279b6c1SSam Ravnborg 2629e279b6c1SSam Ravnborgconfig PCI_BIOS 26303c2362e6SHarvey Harrison def_bool y 2631efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2632e279b6c1SSam Ravnborg 2633e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2634e279b6c1SSam Ravnborgconfig PCI_DIRECT 26353c2362e6SHarvey Harrison def_bool y 26360aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2637e279b6c1SSam Ravnborg 2638e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2639b45c9f36SJan Kiszka bool "Support mmconfig PCI config space access" if X86_64 2640b45c9f36SJan Kiszka default y 26418364e1f8SJan Kiszka depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST) 2642b45c9f36SJan Kiszka depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) 2643e279b6c1SSam Ravnborg 26443ef0e1f8SAndres Salomonconfig PCI_OLPC 26452bdd1b03SAndres Salomon def_bool y 26462bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 26473ef0e1f8SAndres Salomon 2648b5401a96SAlex Nixonconfig PCI_XEN 2649b5401a96SAlex Nixon def_bool y 2650b5401a96SAlex Nixon depends on PCI && XEN 2651b5401a96SAlex Nixon select SWIOTLB_XEN 2652b5401a96SAlex Nixon 2653e279b6c1SSam Ravnborgconfig PCI_DOMAINS 26543c2362e6SHarvey Harrison def_bool y 2655e279b6c1SSam Ravnborg depends on PCI 2656e279b6c1SSam Ravnborg 26578364e1f8SJan Kiszkaconfig MMCONF_FAM10H 26588364e1f8SJan Kiszka def_bool y 26598364e1f8SJan Kiszka depends on X86_64 && PCI_MMCONFIG && ACPI 2660e279b6c1SSam Ravnborg 26613f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 26626a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 26636ea30386SKees Cook depends on PCI 26643f6ea84aSIra W. Snyder help 26653f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 26663f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 26673f6ea84aSIra W. Snyder not have ACPI. 26683f6ea84aSIra W. Snyder 266964a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 267064a5fed6SBjorn Helgaas is known to be incomplete. 267164a5fed6SBjorn Helgaas 267264a5fed6SBjorn Helgaas You should say N unless you know you need this. 267364a5fed6SBjorn Helgaas 2674e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2675e279b6c1SSam Ravnborg 26763a495511SWilliam Breathitt Grayconfig ISA_BUS 267717a2a129SWilliam Breathitt Gray bool "ISA bus support on modern systems" if EXPERT 26783a495511SWilliam Breathitt Gray help 267917a2a129SWilliam Breathitt Gray Expose ISA bus device drivers and options available for selection and 268017a2a129SWilliam Breathitt Gray configuration. Enable this option if your target machine has an ISA 268117a2a129SWilliam Breathitt Gray bus. ISA is an older system, displaced by PCI and newer bus 268217a2a129SWilliam Breathitt Gray architectures -- if your target machine is modern, it probably does 268317a2a129SWilliam Breathitt Gray not have an ISA bus. 26843a495511SWilliam Breathitt Gray 26853a495511SWilliam Breathitt Gray If unsure, say N. 26863a495511SWilliam Breathitt Gray 26871c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2688e279b6c1SSam Ravnborgconfig ISA_DMA_API 26891c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26901c00f016SDavid Rientjes default y 26911c00f016SDavid Rientjes help 26921c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26931c00f016SDavid Rientjes If unsure, say Y. 2694e279b6c1SSam Ravnborg 269551e68d05SLinus Torvaldsif X86_32 269651e68d05SLinus Torvalds 2697e279b6c1SSam Ravnborgconfig ISA 2698e279b6c1SSam Ravnborg bool "ISA support" 26998f9ca475SIngo Molnar ---help--- 2700e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2701e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2702e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2703e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2704e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2705e279b6c1SSam Ravnborg 2706e279b6c1SSam Ravnborgconfig EISA 2707e279b6c1SSam Ravnborg bool "EISA support" 2708e279b6c1SSam Ravnborg depends on ISA 2709e279b6c1SSam Ravnborg ---help--- 2710e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2711e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2712e279b6c1SSam Ravnborg 2713e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2714e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2715e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2716e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2717e279b6c1SSam Ravnborg 2718e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2719e279b6c1SSam Ravnborg 2720e279b6c1SSam Ravnborg Otherwise, say N. 2721e279b6c1SSam Ravnborg 2722e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2723e279b6c1SSam Ravnborg 2724e279b6c1SSam Ravnborgconfig SCx200 2725e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 27268f9ca475SIngo Molnar ---help--- 2727e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2728e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2729e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2730e279b6c1SSam Ravnborg for other scx200_* drivers. 2731e279b6c1SSam Ravnborg 2732e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2733e279b6c1SSam Ravnborg 2734e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2735e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2736592913ecSJohn Stultz depends on SCx200 2737e279b6c1SSam Ravnborg default y 27388f9ca475SIngo Molnar ---help--- 2739e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2740e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2741e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2742e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2743e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2744e279b6c1SSam Ravnborg 27453ef0e1f8SAndres Salomonconfig OLPC 27463ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 274754008979SThomas Gleixner depends on !X86_PAE 27483c554946SAndres Salomon select GPIOLIB 2749dc3119e7SThomas Gleixner select OF 275045bb1674SDaniel Drake select OF_PROMTREE 2751b4e51854SGrant Likely select IRQ_DOMAIN 27528f9ca475SIngo Molnar ---help--- 27533ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 27543ef0e1f8SAndres Salomon XO hardware. 27553ef0e1f8SAndres Salomon 2756a3128588SDaniel Drakeconfig OLPC_XO1_PM 2757a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 275897c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2759a3128588SDaniel Drake select MFD_CORE 2760bf1ebf00SDaniel Drake ---help--- 276197c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2762bf1ebf00SDaniel Drake 2763cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2764cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2765cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2766cfee9597SDaniel Drake ---help--- 2767cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2768cfee9597SDaniel Drake programmable wakeup source. 2769cfee9597SDaniel Drake 27707feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27717feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 277292e830f2SArnd Bergmann depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2773ed8e47feSRandy Dunlap depends on INPUT=y 2774d8d01a63SDaniel Drake select POWER_SUPPLY 27757feda8e9SDaniel Drake ---help--- 27767feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27777bc74b3dSDaniel Drake - EC-driven system wakeups 27787feda8e9SDaniel Drake - Power button 27797bc74b3dSDaniel Drake - Ebook switch 27802cf2baeaSDaniel Drake - Lid switch 2781e1040ac6SDaniel Drake - AC adapter status updates 2782e1040ac6SDaniel Drake - Battery status updates 27837feda8e9SDaniel Drake 2784a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2785a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2786d8d01a63SDaniel Drake depends on OLPC && ACPI 2787d8d01a63SDaniel Drake select POWER_SUPPLY 2788a0f30f59SDaniel Drake ---help--- 2789a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2790a0f30f59SDaniel Drake - EC-driven system wakeups 2791a0f30f59SDaniel Drake - AC adapter status updates 2792a0f30f59SDaniel Drake - Battery status updates 2793e279b6c1SSam Ravnborg 2794d4f3e350SEd Wildgooseconfig ALIX 2795d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2796d4f3e350SEd Wildgoose select GPIOLIB 2797d4f3e350SEd Wildgoose ---help--- 2798d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2799d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2800d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2801d4f3e350SEd Wildgoose get added here. 2802d4f3e350SEd Wildgoose 2803d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2804d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2805d4f3e350SEd Wildgoose 2806d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2807d4f3e350SEd Wildgoose 2808da4e3302SPhilip Prindevilleconfig NET5501 2809da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2810da4e3302SPhilip Prindeville select GPIOLIB 2811da4e3302SPhilip Prindeville ---help--- 2812da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2813da4e3302SPhilip Prindeville 28143197059aSPhilip A. Prindevilleconfig GEOS 28153197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 28163197059aSPhilip A. Prindeville select GPIOLIB 28173197059aSPhilip A. Prindeville depends on DMI 28183197059aSPhilip A. Prindeville ---help--- 28193197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 28203197059aSPhilip A. Prindeville 28217d029125SVivien Didelotconfig TS5500 28227d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 28237d029125SVivien Didelot depends on MELAN 28247d029125SVivien Didelot select CHECK_SIGNATURE 28257d029125SVivien Didelot select NEW_LEDS 28267d029125SVivien Didelot select LEDS_CLASS 28277d029125SVivien Didelot ---help--- 28287d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 28297d029125SVivien Didelot 2830e279b6c1SSam Ravnborgendif # X86_32 2831e279b6c1SSam Ravnborg 283223ac4ae8SAndreas Herrmannconfig AMD_NB 2833e279b6c1SSam Ravnborg def_bool y 28340e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2835e279b6c1SSam Ravnborg 2836e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2837e279b6c1SSam Ravnborg 2838388b78adSAlexandre Bounineconfig RAPIDIO 2839fdf90abcSAlexandre Bounine tristate "RapidIO support" 2840388b78adSAlexandre Bounine depends on PCI 2841388b78adSAlexandre Bounine default n 2842388b78adSAlexandre Bounine help 2843fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2844388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2845388b78adSAlexandre Bounine 2846388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2847388b78adSAlexandre Bounine 2848e3263ab3SDavid Herrmannconfig X86_SYSFB 2849e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2850e3263ab3SDavid Herrmann help 2851e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2852e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2853e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2854e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2855e3263ab3SDavid Herrmann to x86. 2856e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2857e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2858e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2859e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2860e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2861e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2862e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2863e3263ab3SDavid Herrmann 2864e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2865e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2866e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2867e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2868e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2869e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2870e3263ab3SDavid Herrmann incompatible with simplefb. 2871e3263ab3SDavid Herrmann 2872e3263ab3SDavid Herrmann If unsure, say Y. 2873e3263ab3SDavid Herrmann 2874e279b6c1SSam Ravnborgendmenu 2875e279b6c1SSam Ravnborg 2876e279b6c1SSam Ravnborg 2877e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2878e279b6c1SSam Ravnborg 2879e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2880e279b6c1SSam Ravnborg 2881e279b6c1SSam Ravnborgconfig IA32_EMULATION 2882e279b6c1SSam Ravnborg bool "IA32 Emulation" 2883e279b6c1SSam Ravnborg depends on X86_64 288439f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2885d1603990SRandy Dunlap select BINFMT_ELF 2886a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 288739f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28888f9ca475SIngo Molnar ---help--- 28895fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28905fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28915fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2892e279b6c1SSam Ravnborg 2893e279b6c1SSam Ravnborgconfig IA32_AOUT 2894e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28956b213e1bSDavid Woodhouse depends on IA32_EMULATION 28968f9ca475SIngo Molnar ---help--- 2897e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2898e279b6c1SSam Ravnborg 28990bf62763SH. Peter Anvinconfig X86_X32 29006ea30386SKees Cook bool "x32 ABI for 64-bit mode" 29019b54050bSBrian Gerst depends on X86_64 29025fd92e65SH. J. Lu ---help--- 29035fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 29045fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 29055fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 29065fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 29075fd92e65SH. J. Lu 29085fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 29095fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 29105fd92e65SH. J. Lu option set. 29115fd92e65SH. J. Lu 2912953fee1dSIngo Molnarconfig COMPAT_32 2913953fee1dSIngo Molnar def_bool y 2914953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2915953fee1dSIngo Molnar select HAVE_UID16 2916953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2917953fee1dSIngo Molnar 2918e279b6c1SSam Ravnborgconfig COMPAT 29193c2362e6SHarvey Harrison def_bool y 29200bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2921e279b6c1SSam Ravnborg 29223120e25eSJan Beulichif COMPAT 2923e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 29243120e25eSJan Beulich def_bool y 2925e279b6c1SSam Ravnborg 2926e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 29273c2362e6SHarvey Harrison def_bool y 29283120e25eSJan Beulich depends on SYSVIPC 29293120e25eSJan Beulichendif 2930ee009e4aSDavid Howells 2931e279b6c1SSam Ravnborgendmenu 2932e279b6c1SSam Ravnborg 2933e279b6c1SSam Ravnborg 2934e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2935e5beae16SKeith Packard def_bool y 2936e5beae16SKeith Packard depends on X86_32 2937e5beae16SKeith Packard 29384692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 29394692d77fSAlessandro Rubini bool 294083125a3aSAlessandro Rubini depends on X86_64 || STA2X11 29414692d77fSAlessandro Rubini 2942f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2943f7219a53SAlessandro Rubini bool 294483125a3aSAlessandro Rubini depends on STA2X11 2945f7219a53SAlessandro Rubini 2946e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2947e585513bSKirill A. Shutemov def_bool y 2948e585513bSKirill A. Shutemov 2949e279b6c1SSam Ravnborgsource "net/Kconfig" 2950e279b6c1SSam Ravnborg 2951e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2952e279b6c1SSam Ravnborg 2953e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2954e279b6c1SSam Ravnborg 2955e279b6c1SSam Ravnborgsource "fs/Kconfig" 2956e279b6c1SSam Ravnborg 2957e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2958e279b6c1SSam Ravnborg 2959e279b6c1SSam Ravnborgsource "security/Kconfig" 2960e279b6c1SSam Ravnborg 2961e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2962e279b6c1SSam Ravnborg 2963edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2964edf88417SAvi Kivity 2965e279b6c1SSam Ravnborgsource "lib/Kconfig" 2966