1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 2daa93fabSSam Ravnborg# Select 32 or 64 bit 3daa93fabSSam Ravnborgconfig 64BIT 4104daea1SMasahiro Yamada bool "64-bit kernel" if "$(ARCH)" = "x86" 5104daea1SMasahiro Yamada default "$(ARCH)" != "i386" 68f9ca475SIngo Molnar ---help--- 7daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 8daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 9daa93fabSSam Ravnborg 10daa93fabSSam Ravnborgconfig X86_32 113120e25eSJan Beulich def_bool y 123120e25eSJan Beulich depends on !64BIT 13341c787eSIngo Molnar # Options that are inherently 32-bit kernel only: 14341c787eSIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION 15341c787eSIngo Molnar select CLKSRC_I8253 16341c787eSIngo Molnar select CLONE_BACKWARDS 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 31f616ab59SChristoph Hellwig select NEED_DMA_MAP_STATE 3209230cbcSChristoph Hellwig select SWIOTLB 33d94e0685SIngo Molnar select X86_DEV_DMA_OPS 34f8781c4aSDominik Brodowski select ARCH_HAS_SYSCALL_WRAPPER 351032c0baSSam Ravnborg 36d94e0685SIngo Molnar# 37d94e0685SIngo Molnar# Arch settings 38d94e0685SIngo Molnar# 39d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 40d94e0685SIngo Molnar# ported to 32-bit as well. ) 41d94e0685SIngo Molnar# 428d5fffb9SSam Ravnborgconfig X86 433c2362e6SHarvey Harrison def_bool y 44c763ea26SIngo Molnar # 45c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 46c763ea26SIngo Molnar # 476471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 486e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 496471b825SIngo Molnar select ANON_INODES 506471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 512a21ad57SThomas Gleixner select ARCH_CLOCKSOURCE_INIT 526471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 5391dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 54fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5521266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 566471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5772d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 58316d097cSDave Hansen select ARCH_HAS_FILTER_PGPROT 596974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 60957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 615c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 6210bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 63c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 643010a5eaSLaurent Dufour select ARCH_HAS_PTE_SPECIAL 6539208aa7SKees Cook select ARCH_HAS_REFCOUNT 660aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 67092b31aaSDan Williams select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE 68d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 696471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 70ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 71ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 72ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 73c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 7465f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 756471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 766471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 7777fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 785e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 792c870e61SArnd Bergmann select ARCH_SUPPORTS_ACPI 806471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 816471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 826471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 836471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 846471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 85ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 86c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 8738d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 886471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 896471b825SIngo Molnar select CLKEVT_I8253 906471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 916471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 926471b825SIngo Molnar select DCACHE_WORD_ACCESS 93fec777c3SChristoph Hellwig select DMA_DIRECT_OPS 9445471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 9545471cd9SLinus Torvalds select EDAC_SUPPORT 966471b825SIngo Molnar select GENERIC_CLOCKEVENTS 976471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 986471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 996471b825SIngo Molnar select GENERIC_CMOS_UPDATE 1006471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 10161dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 1026471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 1036471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 1046471b825SIngo Molnar select GENERIC_IOMAP 105c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 1060fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 107ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1086471b825SIngo Molnar select GENERIC_IRQ_PROBE 109c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1106471b825SIngo Molnar select GENERIC_IRQ_SHOW 1116471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1126471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1136471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1146471b825SIngo Molnar select GENERIC_STRNLEN_USER 1156471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1167edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1176471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1186471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1196471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1206471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1216471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1226471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 123b34006c4SArd Biesheuvel select HAVE_ARCH_JUMP_LABEL_RELATIVE 124d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1256471b825SIngo Molnar select HAVE_ARCH_KGDB 1269e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1279e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1281b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 129271ca788SArd Biesheuvel select HAVE_ARCH_PREL32_RELOCATIONS 1306471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 131f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 132afaef01cSAlexander Popov select HAVE_ARCH_STACKLEAK 1336471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1346471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 135a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 136e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 137c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1386471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1396471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1406471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 141c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1426471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1436471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1446471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1459c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 146677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 14706aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 14803f5781bSWang YanQing select HAVE_EBPF_JIT 14958340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1505f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 151644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1526471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1536471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1546471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1556b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1560067f129SK.Prasad select HAVE_HW_BREAKPOINT 1576471b825SIngo Molnar select HAVE_IDE 1586471b825SIngo Molnar select HAVE_IOREMAP_PROT 1596471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1606471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1616471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1626471b825SIngo Molnar select HAVE_KERNEL_GZIP 1636471b825SIngo Molnar select HAVE_KERNEL_LZ4 1646471b825SIngo Molnar select HAVE_KERNEL_LZMA 1656471b825SIngo Molnar select HAVE_KERNEL_LZO 1666471b825SIngo Molnar select HAVE_KERNEL_XZ 1676471b825SIngo Molnar select HAVE_KPROBES 1686471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 169540adea3SMasami Hiramatsu select HAVE_FUNCTION_ERROR_INJECTION 1706471b825SIngo Molnar select HAVE_KRETPROBES 1716471b825SIngo Molnar select HAVE_KVM 1726471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1736471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1740102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 175ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 17642a0bb3fSPetr Mladek select HAVE_NMI 1776471b825SIngo Molnar select HAVE_OPROFILE 1786471b825SIngo Molnar select HAVE_OPTPROBES 1796471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1806471b825SIngo Molnar select HAVE_PERF_EVENTS 181c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 18292e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 183c5e63197SJiri Olsa select HAVE_PERF_REGS 184c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 18548a8b97cSPeter Zijlstra select HAVE_RCU_TABLE_FREE if PARAVIRT 186d86564a2SPeter Zijlstra select HAVE_RCU_TABLE_INVALIDATE if HAVE_RCU_TABLE_FREE 1876471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 1886415b38bSJiri Slaby select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION 1893c88ee19SMasami Hiramatsu select HAVE_FUNCTION_ARG_ACCESS_API 190d148eac0SMasahiro Yamada select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR 191c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 192d6761b8fSMathieu Desnoyers select HAVE_RSEQ 1936471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1946471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1957c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 19605736e4aSThomas Gleixner select HOTPLUG_SMT if SMP 197c0185808SThomas Gleixner select IRQ_FORCED_THREADING 19886596f0aSChristoph Hellwig select NEED_SG_DMA_LENGTH 199df65c1bcSThomas Gleixner select PCI_LOCKLESS_CONFIG 2006471b825SIngo Molnar select PERF_EVENTS 2013195ef59SPrarit Bhargava select RTC_LIB 202d6faca40SArnd Bergmann select RTC_MC146818_LIB 2036471b825SIngo Molnar select SPARSE_IRQ 20483fe27eaSPranith Kumar select SRCU 2056471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 20615f4eae7SAndy Lutomirski select THREAD_INFO_IN_TASK 2076471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 2086471b825SIngo Molnar select VIRT_TO_BUS 2096471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 2107d8330a5SBalbir Singh 211ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 2123120e25eSJan Beulich def_bool y 2133120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 214ba7e4d13SIngo Molnar 21551b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 21651b26adaSLinus Torvalds string 21751b26adaSLinus Torvalds default "elf32-i386" if X86_32 21851b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 21951b26adaSLinus Torvalds 22073531905SSam Ravnborgconfig ARCH_DEFCONFIG 221b9b39bfbSSam Ravnborg string 22273531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 22373531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 224b9b39bfbSSam Ravnborg 2258d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 2263c2362e6SHarvey Harrison def_bool y 2278d5fffb9SSam Ravnborg 2288d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 2293c2362e6SHarvey Harrison def_bool y 2308d5fffb9SSam Ravnborg 2318d5fffb9SSam Ravnborgconfig MMU 2323c2362e6SHarvey Harrison def_bool y 2338d5fffb9SSam Ravnborg 2349e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 2359e08f57dSDaniel Cashman default 28 if 64BIT 2369e08f57dSDaniel Cashman default 8 2379e08f57dSDaniel Cashman 2389e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 2399e08f57dSDaniel Cashman default 32 if 64BIT 2409e08f57dSDaniel Cashman default 16 2419e08f57dSDaniel Cashman 2429e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 2439e08f57dSDaniel Cashman default 8 2449e08f57dSDaniel Cashman 2459e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 2469e08f57dSDaniel Cashman default 16 2479e08f57dSDaniel Cashman 2488d5fffb9SSam Ravnborgconfig SBUS 2498d5fffb9SSam Ravnborg bool 2508d5fffb9SSam Ravnborg 2518d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2523120e25eSJan Beulich def_bool y 2533120e25eSJan Beulich depends on ISA_DMA_API 2548d5fffb9SSam Ravnborg 2558d5fffb9SSam Ravnborgconfig GENERIC_BUG 2563c2362e6SHarvey Harrison def_bool y 2578d5fffb9SSam Ravnborg depends on BUG 258b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 259b93a531eSJan Beulich 260b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 261b93a531eSJan Beulich bool 2628d5fffb9SSam Ravnborg 2638d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2643c2362e6SHarvey Harrison def_bool y 2658d5fffb9SSam Ravnborg 2668d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2673120e25eSJan Beulich def_bool y 2683120e25eSJan Beulich depends on ISA_DMA_API 2698d5fffb9SSam Ravnborg 2701032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2713120e25eSJan Beulich def_bool y 2721032c0baSSam Ravnborg 2731032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2741032c0baSSam Ravnborg def_bool y 2751032c0baSSam Ravnborg 2769a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2779a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2788d5fffb9SSam Ravnborg 2791b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2801b27d05bSPekka Enberg def_bool y 2811b27d05bSPekka Enberg 282316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT 283316d097cSDave Hansen def_bool y 284316d097cSDave Hansen 285dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 28689c9c4c5SBrian Gerst def_bool y 287b32ef636Stravis@sgi.com 28808fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 28908fc4580STejun Heo def_bool y 29008fc4580STejun Heo 29108fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 29211124411STejun Heo def_bool y 29311124411STejun Heo 294801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 295801e4062SJohannes Berg def_bool y 296801e4062SJohannes Berg 297f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 298f4cb5700SJohannes Berg def_bool y 299f4cb5700SJohannes Berg 300cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 301cfe28c5dSSteve Capper def_bool y 302cfe28c5dSSteve Capper 30353313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 30453313b2cSSteve Capper def_bool y 30553313b2cSSteve Capper 3068d5fffb9SSam Ravnborgconfig ZONE_DMA32 307e0fd24a3SJan Beulich def_bool y if X86_64 3088d5fffb9SSam Ravnborg 3098d5fffb9SSam Ravnborgconfig AUDIT_ARCH 310e0fd24a3SJan Beulich def_bool y if X86_64 3118d5fffb9SSam Ravnborg 312765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 313765c68bdSIngo Molnar def_bool y 314765c68bdSIngo Molnar 3156a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3166a11f75bSAkinobu Mita def_bool y 3176a11f75bSAkinobu Mita 318d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 319d6f2d75aSAndrey Ryabinin hex 320d6f2d75aSAndrey Ryabinin depends on KASAN 321d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 322d6f2d75aSAndrey Ryabinin 32369575d38SShane Wangconfig HAVE_INTEL_TXT 32469575d38SShane Wang def_bool y 3256ea30386SKees Cook depends on INTEL_IOMMU && ACPI 32669575d38SShane Wang 3276b0c3d44SSam Ravnborgconfig X86_32_SMP 3286b0c3d44SSam Ravnborg def_bool y 3296b0c3d44SSam Ravnborg depends on X86_32 && SMP 3306b0c3d44SSam Ravnborg 3316b0c3d44SSam Ravnborgconfig X86_64_SMP 3326b0c3d44SSam Ravnborg def_bool y 3336b0c3d44SSam Ravnborg depends on X86_64 && SMP 3346b0c3d44SSam Ravnborg 335ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 336ccbeed3aSTejun Heo def_bool y 3378458f8c2SMasahiro Yamada depends on X86_32 && !STACKPROTECTOR 338ccbeed3aSTejun Heo 3392b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3402b144498SSrikar Dronamraju def_bool y 3412b144498SSrikar Dronamraju 342d20642f0SRob Herringconfig FIX_EARLYCON_MEM 343d20642f0SRob Herring def_bool y 344d20642f0SRob Herring 34594d49eb3SKirill A. Shutemovconfig DYNAMIC_PHYSICAL_MASK 34694d49eb3SKirill A. Shutemov bool 34794d49eb3SKirill A. Shutemov 34898233368SKirill A. Shutemovconfig PGTABLE_LEVELS 34998233368SKirill A. Shutemov int 35077ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 35198233368SKirill A. Shutemov default 4 if X86_64 35298233368SKirill A. Shutemov default 3 if X86_PAE 35398233368SKirill A. Shutemov default 2 35498233368SKirill A. Shutemov 3552a61f474SMasahiro Yamadaconfig CC_HAS_SANE_STACKPROTECTOR 3562a61f474SMasahiro Yamada bool 3572a61f474SMasahiro Yamada default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT 3582a61f474SMasahiro Yamada default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC)) 3592a61f474SMasahiro Yamada help 3602a61f474SMasahiro Yamada We have to make sure stack protector is unconditionally disabled if 3612a61f474SMasahiro Yamada the compiler produces broken code. 3622a61f474SMasahiro Yamada 363506f1d07SSam Ravnborgmenu "Processor type and features" 364506f1d07SSam Ravnborg 3655ee71535SRandy Dunlapconfig ZONE_DMA 3665ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3675ee71535SRandy Dunlap default y 3685ee71535SRandy Dunlap help 3695ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3705ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3715ee71535SRandy Dunlap Disable if no such devices will be used. 3725ee71535SRandy Dunlap 3735ee71535SRandy Dunlap If unsure, say Y. 3745ee71535SRandy Dunlap 375506f1d07SSam Ravnborgconfig SMP 376506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 377506f1d07SSam Ravnborg ---help--- 378506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3794a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3804a474157SRobert Graffham than one CPU, say Y. 381506f1d07SSam Ravnborg 3824a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 383506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 384506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3854a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 386506f1d07SSam Ravnborg will run faster if you say N here. 387506f1d07SSam Ravnborg 388506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 389506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 390506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 391506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 392506f1d07SSam Ravnborg 393506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 394506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 395506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 396506f1d07SSam Ravnborg 397395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 398c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 399506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 400506f1d07SSam Ravnborg 401506f1d07SSam Ravnborg If you don't know what to do here, say N. 402506f1d07SSam Ravnborg 4039def39beSJosh Triplettconfig X86_FEATURE_NAMES 4049def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 4059def39beSJosh Triplett default y 4069def39beSJosh Triplett ---help--- 4079def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 4089def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 4099def39beSJosh Triplett messages. You can disable this to save space, at the expense of 4109def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 4119def39beSJosh Triplett 4129def39beSJosh Triplett If in doubt, say Y. 4139def39beSJosh Triplett 41406cd9a7dSYinghai Luconfig X86_X2APIC 41506cd9a7dSYinghai Lu bool "Support x2apic" 41619e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 41706cd9a7dSYinghai Lu ---help--- 41806cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 41906cd9a7dSYinghai Lu 42006cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 42106cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 42206cd9a7dSYinghai Lu 42306cd9a7dSYinghai Lu If you don't know what to do here, say N. 42406cd9a7dSYinghai Lu 4256695c85bSYinghai Luconfig X86_MPPARSE 4266e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4277a527688SJan Beulich default y 4285ab74722SIngo Molnar depends on X86_LOCAL_APIC 4298f9ca475SIngo Molnar ---help--- 4306695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4316695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4326695c85bSYinghai Lu 433ddd70cf9SJun Nakajimaconfig GOLDFISH 434ddd70cf9SJun Nakajima def_bool y 435ddd70cf9SJun Nakajima depends on X86_GOLDFISH 436ddd70cf9SJun Nakajima 43776b04384SDavid Woodhouseconfig RETPOLINE 43876b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 43976b04384SDavid Woodhouse default y 440d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 44176b04384SDavid Woodhouse help 44276b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 44376b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 44476b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 44576b04384SDavid Woodhouse support for full protection. The kernel may run slower. 44676b04384SDavid Woodhouse 44776b04384SDavid Woodhouse Without compiler support, at least indirect branches in assembler 44876b04384SDavid Woodhouse code are eliminated. Since this includes the syscall entry path, 44976b04384SDavid Woodhouse it is not entirely pointless. 45076b04384SDavid Woodhouse 451*6fe07ce3SBabu Mogerconfig RESCTRL 452*6fe07ce3SBabu Moger bool "Resource Control support" 453*6fe07ce3SBabu Moger depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) 45459fe5a77SThomas Gleixner select KERNFS 45578e99b4aSFenghua Yu help 456*6fe07ce3SBabu Moger Enable Resource Control support. 457*6fe07ce3SBabu Moger 458*6fe07ce3SBabu Moger Provide support for the allocation and monitoring of system resources 459*6fe07ce3SBabu Moger usage by the CPU. 460*6fe07ce3SBabu Moger 461*6fe07ce3SBabu Moger Intel calls this Intel Resource Director Technology 462*6fe07ce3SBabu Moger (Intel(R) RDT). More information about RDT can be found in the 463*6fe07ce3SBabu Moger Intel x86 Architecture Software Developer Manual. 464*6fe07ce3SBabu Moger 465*6fe07ce3SBabu Moger AMD calls this AMD Platform Quality of Service (AMD QoS). 466*6fe07ce3SBabu Moger More information about AMD QoS can be found in the AMD64 Technology 467*6fe07ce3SBabu Moger Platform Quality of Service Extensions manual. 46878e99b4aSFenghua Yu 46978e99b4aSFenghua Yu Say N if unsure. 47078e99b4aSFenghua Yu 4718425091fSRavikiran G Thirumalaiif X86_32 472a0d0bb4dSRandy Dunlapconfig X86_BIGSMP 473a0d0bb4dSRandy Dunlap bool "Support for big SMP systems with more than 8 CPUs" 474a0d0bb4dSRandy Dunlap depends on SMP 475a0d0bb4dSRandy Dunlap ---help--- 476a0d0bb4dSRandy Dunlap This option is needed for the systems that have more than 8 CPUs 477a0d0bb4dSRandy Dunlap 478c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 479c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 480c5c606d9SRavikiran G Thirumalai default y 4818f9ca475SIngo Molnar ---help--- 48206ac8346SIngo Molnar If you disable this option then the kernel will only support 48306ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 48406ac8346SIngo Molnar systems out there.) 48506ac8346SIngo Molnar 4868425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4878425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 488cb7b8023SBen Hutchings Goldfish (Android emulator) 4898425091fSRavikiran G Thirumalai AMD Elan 4908425091fSRavikiran G Thirumalai RDC R-321x SoC 4918425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 49283125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4933f4110a4SThomas Gleixner Moorestown MID devices 49406ac8346SIngo Molnar 49506ac8346SIngo Molnar If you have one of these systems, or if you want to build a 49606ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4978425091fSRavikiran G Thirumalaiendif 49806ac8346SIngo Molnar 4998425091fSRavikiran G Thirumalaiif X86_64 5008425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 5018425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 5028425091fSRavikiran G Thirumalai default y 5038425091fSRavikiran G Thirumalai ---help--- 5048425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 5058425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 5068425091fSRavikiran G Thirumalai systems out there.) 5078425091fSRavikiran G Thirumalai 5088425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 5098425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 51044b111b5SSteffen Persvold Numascale NumaChip 5118425091fSRavikiran G Thirumalai ScaleMP vSMP 5128425091fSRavikiran G Thirumalai SGI Ultraviolet 5138425091fSRavikiran G Thirumalai 5148425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 5158425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 5168425091fSRavikiran G Thirumalaiendif 517c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 518c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 51944b111b5SSteffen Persvoldconfig X86_NUMACHIP 52044b111b5SSteffen Persvold bool "Numascale NumaChip" 52144b111b5SSteffen Persvold depends on X86_64 52244b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 52344b111b5SSteffen Persvold depends on NUMA 52444b111b5SSteffen Persvold depends on SMP 52544b111b5SSteffen Persvold depends on X86_X2APIC 526f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 52744b111b5SSteffen Persvold ---help--- 52844b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 52944b111b5SSteffen Persvold enable more than ~168 cores. 53044b111b5SSteffen Persvold If you don't have one of these, you should say N here. 53103b48632SNick Piggin 5326a48565eSIngo Molnarconfig X86_VSMP 533c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5346276a074SBorislav Petkov select HYPERVISOR_GUEST 5356a48565eSIngo Molnar select PARAVIRT 5366a48565eSIngo Molnar depends on X86_64 && PCI 537c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 538ead91d4bSShai Fultheim depends on SMP 5398f9ca475SIngo Molnar ---help--- 5406a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5416a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5426a48565eSIngo Molnar if you have one of these machines. 5436a48565eSIngo Molnar 544c5c606d9SRavikiran G Thirumalaiconfig X86_UV 545c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 546c5c606d9SRavikiran G Thirumalai depends on X86_64 547c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 54854c28d29SJack Steiner depends on NUMA 5491ecb4ae5SAndrew Morton depends on EFI 5509d6c26e7SSuresh Siddha depends on X86_X2APIC 5511222e564SIngo Molnar depends on PCI 552c5c606d9SRavikiran G Thirumalai ---help--- 553c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 554c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 555c5c606d9SRavikiran G Thirumalai 556c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 557c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 558506f1d07SSam Ravnborg 559ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 560ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 561cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 562ddd70cf9SJun Nakajima ---help--- 563ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 564ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 565ddd70cf9SJun Nakajima Goldfish emulator say N here. 566ddd70cf9SJun Nakajima 567c751e17bSThomas Gleixnerconfig X86_INTEL_CE 568c751e17bSThomas Gleixner bool "CE4100 TV platform" 569c751e17bSThomas Gleixner depends on PCI 570c751e17bSThomas Gleixner depends on PCI_GODIRECT 5716084a6e2SJiang Liu depends on X86_IO_APIC 572c751e17bSThomas Gleixner depends on X86_32 573c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 57437bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 575da6b737bSSebastian Andrzej Siewior select OF 576da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 577c751e17bSThomas Gleixner ---help--- 578c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 579c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 580c751e17bSThomas Gleixner boxes and media devices. 581c751e17bSThomas Gleixner 5824cb9b00fSDavid Cohenconfig X86_INTEL_MID 58343605ef1SAlan Cox bool "Intel MID platform support" 58443605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 585edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5861ea7c673SAlan Cox depends on PCI 5873fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5881ea7c673SAlan Cox depends on X86_IO_APIC 5897c9c3a1eSAlan Cox select SFI 5904cb9b00fSDavid Cohen select I2C 5917c9c3a1eSAlan Cox select DW_APB_TIMER 5921ea7c673SAlan Cox select APB_TIMER 5931ea7c673SAlan Cox select INTEL_SCU_IPC 59415a713dfSMika Westerberg select MFD_INTEL_MSIC 5951ea7c673SAlan Cox ---help--- 5964cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5974cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5984cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5991ea7c673SAlan Cox 6004cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 6014cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 60243605ef1SAlan Cox 6038bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 6048bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 6058bbc2a13SBryan O'Donoghue depends on X86_32 6068bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 6078bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 6088bbc2a13SBryan O'Donoghue depends on X86_TSC 6098bbc2a13SBryan O'Donoghue depends on PCI 6108bbc2a13SBryan O'Donoghue depends on PCI_GOANY 6118bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 6128bbc2a13SBryan O'Donoghue select IOSF_MBI 6138bbc2a13SBryan O'Donoghue select INTEL_IMR 6149ab6eb51SAndy Shevchenko select COMMON_CLK 6158bbc2a13SBryan O'Donoghue ---help--- 6168bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 6178bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 6188bbc2a13SBryan O'Donoghue compatible Intel Galileo. 6198bbc2a13SBryan O'Donoghue 6203d48aab1SMika Westerbergconfig X86_INTEL_LPSS 6213d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 622eebb3e8dSAndy Shevchenko depends on X86 && ACPI 6233d48aab1SMika Westerberg select COMMON_CLK 6240f531431SMathias Nyman select PINCTRL 625eebb3e8dSAndy Shevchenko select IOSF_MBI 6263d48aab1SMika Westerberg ---help--- 6273d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6283d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6290f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6300f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6313d48aab1SMika Westerberg 63292082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 63392082a88SKen Xue bool "AMD ACPI2Platform devices support" 63492082a88SKen Xue depends on ACPI 63592082a88SKen Xue select COMMON_CLK 63692082a88SKen Xue select PINCTRL 63792082a88SKen Xue ---help--- 63892082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 63992082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 64092082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 64192082a88SKen Xue implemented under PINCTRL subsystem. 64292082a88SKen Xue 643ced3ce76SDavid E. Boxconfig IOSF_MBI 644ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 645ced3ce76SDavid E. Box depends on PCI 646ced3ce76SDavid E. Box ---help--- 647ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 648ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 649ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 650ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 651ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 652ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 653ced3ce76SDavid E. Box This list is not meant to be exclusive. 654ced3ce76SDavid E. Box - BayTrail 655ced3ce76SDavid E. Box - Braswell 656ced3ce76SDavid E. Box - Quark 657ced3ce76SDavid E. Box 658ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 659ced3ce76SDavid E. Box 660ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 661ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 662ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 663ed2226bdSDavid E. Box ---help--- 664ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 665ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 666ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 667ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 668ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 669ed2226bdSDavid E. Box device they want to access. 670ed2226bdSDavid E. Box 671ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 672ed2226bdSDavid E. Box 673c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 674c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 675506f1d07SSam Ravnborg depends on X86_32 676c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 677c5c606d9SRavikiran G Thirumalai select M486 678c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 679c5c606d9SRavikiran G Thirumalai ---help--- 680c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 681c5c606d9SRavikiran G Thirumalai as R-8610-(G). 682c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 683c5c606d9SRavikiran G Thirumalai 684e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6859c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6869c398017SIngo Molnar depends on X86_32 && SMP 687c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6888f9ca475SIngo Molnar ---help--- 689b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 690b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 691b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 692b5660ba7SH. Peter Anvin one and will fallback to default. 693d49c4288SYinghai Lu 694c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 695d49c4288SYinghai Lu 696d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6976fc108a0SJan Beulich def_bool y 698d949f36fSLinus Torvalds # MCE code calls memory_failure(): 699d949f36fSLinus Torvalds depends on X86_MCE 700d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 701d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 702d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 703d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 704d949f36fSLinus Torvalds 70583125a3aSAlessandro Rubiniconfig STA2X11 70683125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 70783125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 708b6e05477SChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 70983125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 71083125a3aSAlessandro Rubini select X86_DMA_REMAP 71183125a3aSAlessandro Rubini select SWIOTLB 71283125a3aSAlessandro Rubini select MFD_STA2X11 7130145071bSLinus Walleij select GPIOLIB 71483125a3aSAlessandro Rubini ---help--- 71583125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 71683125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 71783125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 71883125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 71983125a3aSAlessandro Rubini standard PC machines. 72083125a3aSAlessandro Rubini 72182148d1dSShérabconfig X86_32_IRIS 72282148d1dSShérab tristate "Eurobraille/Iris poweroff module" 72382148d1dSShérab depends on X86_32 72482148d1dSShérab ---help--- 72582148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 72682148d1dSShérab to shut themselves down properly. A special I/O sequence is 72782148d1dSShérab needed to do so, which is what this module does at 72882148d1dSShérab kernel shutdown. 72982148d1dSShérab 73082148d1dSShérab This is only for Iris machines from EuroBraille. 73182148d1dSShérab 73282148d1dSShérab If unused, say N. 73382148d1dSShérab 734ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7353c2362e6SHarvey Harrison def_bool y 7363c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 737a87d0914SKen Chen depends on X86 7388f9ca475SIngo Molnar ---help--- 739506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 740506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 741506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 742506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 743506f1d07SSam Ravnborg 744506f1d07SSam Ravnborg If in doubt, say "Y". 745506f1d07SSam Ravnborg 7466276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7476276a074SBorislav Petkov bool "Linux guest support" 7488f9ca475SIngo Molnar ---help--- 7496276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7506276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7516276a074SBorislav Petkov setup. 752506f1d07SSam Ravnborg 7536276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7546276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 755506f1d07SSam Ravnborg 7566276a074SBorislav Petkovif HYPERVISOR_GUEST 757506f1d07SSam Ravnborg 758e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 759e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7608f9ca475SIngo Molnar ---help--- 761e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 762e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 763e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 764e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 765e61bd94aSEduardo Pereira Habkost 766c00a280aSJuergen Grossconfig PARAVIRT_XXL 767c00a280aSJuergen Gross bool 768c00a280aSJuergen Gross 7696276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7706276a074SBorislav Petkov bool "paravirt-ops debugging" 7716276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7726276a074SBorislav Petkov ---help--- 7736276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7746276a074SBorislav Petkov a paravirt_op is missing when it is called. 7756276a074SBorislav Petkov 776b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 777b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7786ea30386SKees Cook depends on PARAVIRT && SMP 779b4ecc126SJeremy Fitzhardinge ---help--- 780b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 781b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 782b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 783b4ecc126SJeremy Fitzhardinge 7844c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7854c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 786b4ecc126SJeremy Fitzhardinge 7874c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 788b4ecc126SJeremy Fitzhardinge 78945e898b7SWaiman Longconfig QUEUED_LOCK_STAT 79045e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 791cfd8983fSPeter Zijlstra depends on PARAVIRT_SPINLOCKS && DEBUG_FS 79245e898b7SWaiman Long ---help--- 79345e898b7SWaiman Long Enable the collection of statistical data on the slowpath 79445e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 79545e898b7SWaiman Long them on debugfs. 79645e898b7SWaiman Long 7976276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7986276a074SBorislav Petkov 7996276a074SBorislav Petkovconfig KVM_GUEST 8006276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 8016276a074SBorislav Petkov depends on PARAVIRT 8026276a074SBorislav Petkov select PARAVIRT_CLOCK 8036276a074SBorislav Petkov default y 8046276a074SBorislav Petkov ---help--- 8056276a074SBorislav Petkov This option enables various optimizations for running under the KVM 8066276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 8076276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 8086276a074SBorislav Petkov underlying device model, the host provides the guest with 8096276a074SBorislav Petkov timing infrastructure such as time of day, and system time 8106276a074SBorislav Petkov 8111e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 8121e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 8131e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 8141e20eb85SSrivatsa Vaddagiri ---help--- 8151e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 8161e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 8171e20eb85SSrivatsa Vaddagiri may incur significant overhead. 8181e20eb85SSrivatsa Vaddagiri 8196276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 8206276a074SBorislav Petkov bool "Paravirtual steal time accounting" 8216276a074SBorislav Petkov depends on PARAVIRT 8226276a074SBorislav Petkov ---help--- 8236276a074SBorislav Petkov Select this option to enable fine granularity task steal time 8246276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 8256276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8266276a074SBorislav Petkov that, there can be a small performance impact. 8276276a074SBorislav Petkov 8286276a074SBorislav Petkov If in doubt, say N here. 8296276a074SBorislav Petkov 8307af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8317af192c9SGerd Hoffmann bool 8327af192c9SGerd Hoffmann 8334a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8344a362601SJan Kiszka bool "Jailhouse non-root cell support" 835abde587bSArnd Bergmann depends on X86_64 && PCI 83687e65d05SJan Kiszka select X86_PM_TIMER 8374a362601SJan Kiszka ---help--- 8384a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8394a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8404a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8414a362601SJan Kiszka 8426276a074SBorislav Petkovendif #HYPERVISOR_GUEST 84397349135SJeremy Fitzhardinge 844506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 845506f1d07SSam Ravnborg 846506f1d07SSam Ravnborgconfig HPET_TIMER 8473c2362e6SHarvey Harrison def_bool X86_64 848506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8498f9ca475SIngo Molnar ---help--- 850506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 851506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 852506f1d07SSam Ravnborg present. 853506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 854506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 855506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8564e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8574e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 858506f1d07SSam Ravnborg 859506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 860506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 861506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 862506f1d07SSam Ravnborg 863506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 864506f1d07SSam Ravnborg 865506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8663c2362e6SHarvey Harrison def_bool y 8679d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 868506f1d07SSam Ravnborg 869bb24c471SJacob Panconfig APB_TIMER 870933b9463SAlan Cox def_bool y if X86_INTEL_MID 871933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 87206c3df49SJamie Iles select DW_APB_TIMER 873a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 874bb24c471SJacob Pan help 875bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 876bb24c471SJacob Pan The APBT provides a stable time base on SMP 877bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 878bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 879bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 880bb24c471SJacob Pan 8816a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 882506f1d07SSam Ravnborg# The code disables itself when not needed. 8837ae9392cSThomas Petazzoniconfig DMI 8847ae9392cSThomas Petazzoni default y 885cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8866a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8878f9ca475SIngo Molnar ---help--- 8887ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8897ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8907ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8917ae9392cSThomas Petazzoni BIOS code. 8927ae9392cSThomas Petazzoni 893506f1d07SSam Ravnborgconfig GART_IOMMU 89438901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 895a4ce5a48SChristoph Hellwig select IOMMU_HELPER 896506f1d07SSam Ravnborg select SWIOTLB 89723ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8988f9ca475SIngo Molnar ---help--- 899ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 900ced3c42cSIngo Molnar GART based hardware IOMMUs. 901ced3c42cSIngo Molnar 902ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 903ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 904ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 905ced3c42cSIngo Molnar 906ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 907ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 908ced3c42cSIngo Molnar 909ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 910ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 911ced3c42cSIngo Molnar 32-bit limited device. 912ced3c42cSIngo Molnar 913ced3c42cSIngo Molnar If unsure, say Y. 914506f1d07SSam Ravnborg 915506f1d07SSam Ravnborgconfig CALGARY_IOMMU 916506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 917a4ce5a48SChristoph Hellwig select IOMMU_HELPER 918506f1d07SSam Ravnborg select SWIOTLB 9196ea30386SKees Cook depends on X86_64 && PCI 9208f9ca475SIngo Molnar ---help--- 921506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 922506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 923506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 924506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 925506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 926506f1d07SSam Ravnborg prevents them from going anywhere except their intended 927506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 928506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 929506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 930506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 931506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 932506f1d07SSam Ravnborg If unsure, say Y. 933506f1d07SSam Ravnborg 934506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9353c2362e6SHarvey Harrison def_bool y 9363c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 937506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9388f9ca475SIngo Molnar ---help--- 939506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 940506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 941506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 942506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 943506f1d07SSam Ravnborg If unsure, say Y. 944506f1d07SSam Ravnborg 9451184dc2fSMike Travisconfig MAXSMP 946ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9476ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 94836f5101aSMike Travis select CPUMASK_OFFSTACK 9498f9ca475SIngo Molnar ---help--- 950ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9511184dc2fSMike Travis If unsure, say N. 952506f1d07SSam Ravnborg 953aec6487eSIngo Molnar# 954aec6487eSIngo Molnar# The maximum number of CPUs supported: 955aec6487eSIngo Molnar# 956aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 957aec6487eSIngo Molnar# and which can be configured interactively in the 958aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 959aec6487eSIngo Molnar# 960aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on 961aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel. 962aec6487eSIngo Molnar# 963aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable 964aec6487eSIngo Molnar# interactive configuration. ) 965aec6487eSIngo Molnar# 966a0d0bb4dSRandy Dunlap 967aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN 968a0d0bb4dSRandy Dunlap int 969aec6487eSIngo Molnar default NR_CPUS_RANGE_END if MAXSMP 970a0d0bb4dSRandy Dunlap default 1 if !SMP 971a0d0bb4dSRandy Dunlap default 2 972a0d0bb4dSRandy Dunlap 973aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 974a0d0bb4dSRandy Dunlap int 975a0d0bb4dSRandy Dunlap depends on X86_32 976aec6487eSIngo Molnar default 64 if SMP && X86_BIGSMP 977aec6487eSIngo Molnar default 8 if SMP && !X86_BIGSMP 978a0d0bb4dSRandy Dunlap default 1 if !SMP 979a0d0bb4dSRandy Dunlap 980aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 981a0d0bb4dSRandy Dunlap int 982a0d0bb4dSRandy Dunlap depends on X86_64 983aec6487eSIngo Molnar default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 984aec6487eSIngo Molnar default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 985a0d0bb4dSRandy Dunlap default 1 if !SMP 986aec6487eSIngo Molnar 987aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 988aec6487eSIngo Molnar int 989aec6487eSIngo Molnar depends on X86_32 990aec6487eSIngo Molnar default 32 if X86_BIGSMP 991aec6487eSIngo Molnar default 8 if SMP 992aec6487eSIngo Molnar default 1 if !SMP 993aec6487eSIngo Molnar 994aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 995aec6487eSIngo Molnar int 996aec6487eSIngo Molnar depends on X86_64 997a0d0bb4dSRandy Dunlap default 8192 if MAXSMP 998a0d0bb4dSRandy Dunlap default 64 if SMP 999aec6487eSIngo Molnar default 1 if !SMP 1000a0d0bb4dSRandy Dunlap 1001506f1d07SSam Ravnborgconfig NR_CPUS 100236f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 1003aec6487eSIngo Molnar range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 1004aec6487eSIngo Molnar default NR_CPUS_DEFAULT 10058f9ca475SIngo Molnar ---help--- 1006506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 1007bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 1008cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 1009506f1d07SSam Ravnborg minimum value which makes sense is 2. 1010506f1d07SSam Ravnborg 1011aec6487eSIngo Molnar This is purely to save memory: each supported CPU adds about 8KB 1012aec6487eSIngo Molnar to the kernel image. 1013506f1d07SSam Ravnborg 1014506f1d07SSam Ravnborgconfig SCHED_SMT 1015506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 1016c8e56d20SBorislav Petkov depends on SMP 10178f9ca475SIngo Molnar ---help--- 1018506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 1019506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 1020506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 1021506f1d07SSam Ravnborg N here. 1022506f1d07SSam Ravnborg 1023506f1d07SSam Ravnborgconfig SCHED_MC 10243c2362e6SHarvey Harrison def_bool y 10253c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 1026c8e56d20SBorislav Petkov depends on SMP 10278f9ca475SIngo Molnar ---help--- 1028506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 1029506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 1030506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 1031506f1d07SSam Ravnborg 1032de966cf4STim Chenconfig SCHED_MC_PRIO 1033de966cf4STim Chen bool "CPU core priorities scheduler support" 10340a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 10350a21fc12SIngo Molnar select X86_INTEL_PSTATE 10360a21fc12SIngo Molnar select CPU_FREQ 1037de966cf4STim Chen default y 10385e76b2abSTim Chen ---help--- 1039de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1040de966cf4STim Chen core ordering determined at manufacturing time, which allows 1041de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1042de966cf4STim Chen single threaded workloads) than others. 1043de966cf4STim Chen 1044de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1045de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1046de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1047de966cf4STim Chen overall system performance can be achieved. 1048de966cf4STim Chen 1049de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1050de966cf4STim Chen 1051de966cf4STim Chen If unsure say Y here. 10525e76b2abSTim Chen 105330b8b006SThomas Gleixnerconfig UP_LATE_INIT 105430b8b006SThomas Gleixner def_bool y 1055ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 105630b8b006SThomas Gleixner 1057506f1d07SSam Ravnborgconfig X86_UP_APIC 105850849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 105950849eefSJan Beulich default PCI_MSI 106038a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10618f9ca475SIngo Molnar ---help--- 1062506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1063506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1064506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1065506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1066506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1067506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1068506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1069506f1d07SSam Ravnborg lockups. 1070506f1d07SSam Ravnborg 1071506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1072506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1073506f1d07SSam Ravnborg depends on X86_UP_APIC 10748f9ca475SIngo Molnar ---help--- 1075506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1076506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1077506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1078506f1d07SSam Ravnborg 1079506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1080506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1081506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1082506f1d07SSam Ravnborg 1083506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10843c2362e6SHarvey Harrison def_bool y 10850dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1086b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 108752f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1088506f1d07SSam Ravnborg 1089506f1d07SSam Ravnborgconfig X86_IO_APIC 1090b1da1e71SJan Beulich def_bool y 1091b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1092506f1d07SSam Ravnborg 109341b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 109441b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 109541b9eb26SStefan Assmann depends on X86_IO_APIC 10968f9ca475SIngo Molnar ---help--- 109741b9eb26SStefan Assmann This option enables a workaround that fixes a source of 109841b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 109941b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 110041b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 110141b9eb26SStefan Assmann 110241b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 110341b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 110441b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 110541b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 110641b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 110741b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 110841b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 110941b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 111041b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 111141b9eb26SStefan Assmann down (vital) interrupt lines. 111241b9eb26SStefan Assmann 111341b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 111441b9eb26SStefan Assmann increased on these systems. 111541b9eb26SStefan Assmann 1116506f1d07SSam Ravnborgconfig X86_MCE 1117bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1118648ed940SChen, Gong select GENERIC_ALLOCATOR 1119e57dbaf7SBorislav Petkov default y 1120506f1d07SSam Ravnborg ---help--- 1121bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1122bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1123506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1124bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 11254efc0670SAndi Kleen 11265de97c9fSTony Luckconfig X86_MCELOG_LEGACY 11275de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 11285de97c9fSTony Luck depends on X86_MCE 11295de97c9fSTony Luck ---help--- 11305de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 11315de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 11325de97c9fSTony Luck rasdaemon solution. 11335de97c9fSTony Luck 1134506f1d07SSam Ravnborgconfig X86_MCE_INTEL 11353c2362e6SHarvey Harrison def_bool y 11363c2362e6SHarvey Harrison prompt "Intel MCE features" 1137c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 11388f9ca475SIngo Molnar ---help--- 1139506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1140506f1d07SSam Ravnborg the thermal monitor. 1141506f1d07SSam Ravnborg 1142506f1d07SSam Ravnborgconfig X86_MCE_AMD 11433c2362e6SHarvey Harrison def_bool y 11443c2362e6SHarvey Harrison prompt "AMD MCE features" 1145f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11468f9ca475SIngo Molnar ---help--- 1147506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1148506f1d07SSam Ravnborg the DRAM Error Threshold. 1149506f1d07SSam Ravnborg 11504efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11516fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1152c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11534efc0670SAndi Kleen ---help--- 11544efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11555065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11564efc0670SAndi Kleen line. 11574efc0670SAndi Kleen 1158b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1159b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11606fc108a0SJan Beulich def_bool y 1161b2762686SAndi Kleen 1162ea149b36SAndi Kleenconfig X86_MCE_INJECT 1163bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1164ea149b36SAndi Kleen tristate "Machine check injector support" 1165ea149b36SAndi Kleen ---help--- 1166ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1167ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1168ea149b36SAndi Kleen QA it is safe to say n. 1169ea149b36SAndi Kleen 11704efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11714efc0670SAndi Kleen def_bool y 11725bb38adcSAndi Kleen depends on X86_MCE_INTEL 11734efc0670SAndi Kleen 117407dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1175e633c65aSKan Liang 11765aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11771e642812SIngo Molnar bool "Legacy VM86 support" 1178506f1d07SSam Ravnborg depends on X86_32 11798f9ca475SIngo Molnar ---help--- 11805aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11815aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11825aef51c3SAndy Lutomirski 11835aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11845aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11855aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11865aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11875aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11881e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11891e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11901e642812SIngo Molnar mode might be faster than emulation and you might want to 11911e642812SIngo Molnar enable this option. 11925aef51c3SAndy Lutomirski 11931e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11941e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11951e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11961e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11975aef51c3SAndy Lutomirski 11981e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11991e642812SIngo Molnar and slows down exception handling a tiny bit. 12005aef51c3SAndy Lutomirski 12011e642812SIngo Molnar If unsure, say N here. 12025aef51c3SAndy Lutomirski 12035aef51c3SAndy Lutomirskiconfig VM86 12045aef51c3SAndy Lutomirski bool 12055aef51c3SAndy Lutomirski default X86_LEGACY_VM86 120634273f41SH. Peter Anvin 120734273f41SH. Peter Anvinconfig X86_16BIT 120834273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 120934273f41SH. Peter Anvin default y 1210a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 121134273f41SH. Peter Anvin ---help--- 121234273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 121334273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 121434273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 121534273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 121634273f41SH. Peter Anvin 121734273f41SH. Peter Anvinconfig X86_ESPFIX32 121834273f41SH. Peter Anvin def_bool y 121934273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1220506f1d07SSam Ravnborg 1221197725deSH. Peter Anvinconfig X86_ESPFIX64 1222197725deSH. Peter Anvin def_bool y 122334273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1224506f1d07SSam Ravnborg 12251ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 12261ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 12271ad83c85SAndy Lutomirski default y 12281ad83c85SAndy Lutomirski depends on X86_64 12291ad83c85SAndy Lutomirski ---help--- 12301ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 12311ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 12321ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 12331ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 12341ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 12351ad83c85SAndy Lutomirski 0xffffffffff600?00. 12361ad83c85SAndy Lutomirski 12371ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12381ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12391ad83c85SAndy Lutomirski 12401ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12411ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12421ad83c85SAndy Lutomirski 1243506f1d07SSam Ravnborgconfig TOSHIBA 1244506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1245506f1d07SSam Ravnborg depends on X86_32 1246506f1d07SSam Ravnborg ---help--- 1247506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1248506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1249506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1250506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1251506f1d07SSam Ravnborg 1252506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1253506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1254506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1255506f1d07SSam Ravnborg 1256506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1257506f1d07SSam Ravnborg Say N otherwise. 1258506f1d07SSam Ravnborg 1259506f1d07SSam Ravnborgconfig I8K 1260039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1261949a9d70SJean Delvare select HWMON 1262039ae585SPali Rohár select SENSORS_DELL_SMM 1263506f1d07SSam Ravnborg ---help--- 1264039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1265039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1266039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1267039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1268039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1269039ae585SPali Rohár needed userspace package i8kutils. 1270506f1d07SSam Ravnborg 1271039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1272039ae585SPali Rohár use userspace package i8kutils. 1273506f1d07SSam Ravnborg Say N otherwise. 1274506f1d07SSam Ravnborg 1275506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12769ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12779ba16087SJan Beulich depends on X86_32 1278506f1d07SSam Ravnborg ---help--- 1279506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1280506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1281506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1282506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1283506f1d07SSam Ravnborg system. 1284506f1d07SSam Ravnborg 1285506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12865e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1287506f1d07SSam Ravnborg 1288506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1289506f1d07SSam Ravnborg enable this option even if you don't need it. 1290506f1d07SSam Ravnborg Say N otherwise. 1291506f1d07SSam Ravnborg 1292506f1d07SSam Ravnborgconfig MICROCODE 12939a2bc335SBorislav Petkov bool "CPU microcode loading support" 12949a2bc335SBorislav Petkov default y 129580030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1296506f1d07SSam Ravnborg select FW_LOADER 1297506f1d07SSam Ravnborg ---help--- 1298506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12995f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 13005f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 13015f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 13025f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 13035f9c01aaSBorislav Petkov the Linux kernel. 1304506f1d07SSam Ravnborg 13055f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 13061897a969SJaak Ristioja in Documentation/x86/microcode.txt. For that you need to enable 13075f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 13085f9c01aaSBorislav Petkov initrd for microcode blobs. 1309506f1d07SSam Ravnborg 1310c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1311c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1312c508c46eSBenjamin Gilbert config option. 1313506f1d07SSam Ravnborg 13148d86f390SPeter Orubaconfig MICROCODE_INTEL 1315e43f6e67SBorislav Petkov bool "Intel microcode loading support" 13168d86f390SPeter Oruba depends on MICROCODE 13178d86f390SPeter Oruba default MICROCODE 13188d86f390SPeter Oruba select FW_LOADER 13198f9ca475SIngo Molnar ---help--- 13208d86f390SPeter Oruba This options enables microcode patch loading support for Intel 13218d86f390SPeter Oruba processors. 13228d86f390SPeter Oruba 1323b8989db9SAlan For the current Intel microcode data package go to 1324b8989db9SAlan <https://downloadcenter.intel.com> and search for 1325b8989db9SAlan 'Linux Processor Microcode Data File'. 13268d86f390SPeter Oruba 132780cc9f10SPeter Orubaconfig MICROCODE_AMD 1328e43f6e67SBorislav Petkov bool "AMD microcode loading support" 132980cc9f10SPeter Oruba depends on MICROCODE 133080cc9f10SPeter Oruba select FW_LOADER 13318f9ca475SIngo Molnar ---help--- 133280cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 133380cc9f10SPeter Oruba processors will be enabled. 133480cc9f10SPeter Oruba 1335506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 13363c2362e6SHarvey Harrison def_bool y 1337506f1d07SSam Ravnborg depends on MICROCODE 1338506f1d07SSam Ravnborg 1339506f1d07SSam Ravnborgconfig X86_MSR 1340506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13418f9ca475SIngo Molnar ---help--- 1342506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1343506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1344506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1345506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1346506f1d07SSam Ravnborg systems. 1347506f1d07SSam Ravnborg 1348506f1d07SSam Ravnborgconfig X86_CPUID 1349506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13508f9ca475SIngo Molnar ---help--- 1351506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1352506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1353506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1354506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1355506f1d07SSam Ravnborg 1356506f1d07SSam Ravnborgchoice 1357506f1d07SSam Ravnborg prompt "High Memory Support" 13586fc108a0SJan Beulich default HIGHMEM4G 1359506f1d07SSam Ravnborg depends on X86_32 1360506f1d07SSam Ravnborg 1361506f1d07SSam Ravnborgconfig NOHIGHMEM 1362506f1d07SSam Ravnborg bool "off" 1363506f1d07SSam Ravnborg ---help--- 1364506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1365506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1366506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1367506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1368506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1369506f1d07SSam Ravnborg "high memory". 1370506f1d07SSam Ravnborg 1371506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1372506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1373506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1374506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1375506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1376506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1377506f1d07SSam Ravnborg possible. 1378506f1d07SSam Ravnborg 1379506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1380506f1d07SSam Ravnborg answer "4GB" here. 1381506f1d07SSam Ravnborg 1382506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1383506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1384506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1385506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1386506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1387506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1388506f1d07SSam Ravnborg 1389506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1390506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1391506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1392506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1393506f1d07SSam Ravnborg kernel at boot time.) 1394506f1d07SSam Ravnborg 1395506f1d07SSam Ravnborg If unsure, say "off". 1396506f1d07SSam Ravnborg 1397506f1d07SSam Ravnborgconfig HIGHMEM4G 1398506f1d07SSam Ravnborg bool "4GB" 13998f9ca475SIngo Molnar ---help--- 1400506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1401506f1d07SSam Ravnborg gigabytes of physical RAM. 1402506f1d07SSam Ravnborg 1403506f1d07SSam Ravnborgconfig HIGHMEM64G 1404506f1d07SSam Ravnborg bool "64GB" 140569b8d3fcSMatthew Whitehead depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1406506f1d07SSam Ravnborg select X86_PAE 14078f9ca475SIngo Molnar ---help--- 1408506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1409506f1d07SSam Ravnborg gigabytes of physical RAM. 1410506f1d07SSam Ravnborg 1411506f1d07SSam Ravnborgendchoice 1412506f1d07SSam Ravnborg 1413506f1d07SSam Ravnborgchoice 14146a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1415506f1d07SSam Ravnborg default VMSPLIT_3G 1416506f1d07SSam Ravnborg depends on X86_32 14178f9ca475SIngo Molnar ---help--- 1418506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1419506f1d07SSam Ravnborg 1420506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1421506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1422506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1423506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1424506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1425506f1d07SSam Ravnborg available to user programs, making the address space there 1426506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1427506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1428506f1d07SSam Ravnborg kernel modules. 1429506f1d07SSam Ravnborg 1430506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1431506f1d07SSam Ravnborg option alone! 1432506f1d07SSam Ravnborg 1433506f1d07SSam Ravnborg config VMSPLIT_3G 1434506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1435506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1436506f1d07SSam Ravnborg depends on !X86_PAE 1437506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1438506f1d07SSam Ravnborg config VMSPLIT_2G 1439506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1440506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1441506f1d07SSam Ravnborg depends on !X86_PAE 1442506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1443506f1d07SSam Ravnborg config VMSPLIT_1G 1444506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1445506f1d07SSam Ravnborgendchoice 1446506f1d07SSam Ravnborg 1447506f1d07SSam Ravnborgconfig PAGE_OFFSET 1448506f1d07SSam Ravnborg hex 1449506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1450506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1451506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1452506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1453506f1d07SSam Ravnborg default 0xC0000000 1454506f1d07SSam Ravnborg depends on X86_32 1455506f1d07SSam Ravnborg 1456506f1d07SSam Ravnborgconfig HIGHMEM 14573c2362e6SHarvey Harrison def_bool y 1458506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1459506f1d07SSam Ravnborg 1460506f1d07SSam Ravnborgconfig X86_PAE 14619ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1462506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 1463d4a451d5SChristoph Hellwig select PHYS_ADDR_T_64BIT 14649d99c712SChristian Melki select SWIOTLB 14658f9ca475SIngo Molnar ---help--- 1466506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1467506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1468506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1469506f1d07SSam Ravnborg consumes more pagetable space per process. 1470506f1d07SSam Ravnborg 147177ef56e4SKirill A. Shutemovconfig X86_5LEVEL 147277ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 1473eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 1474162434e7SKirill A. Shutemov select SPARSEMEM_VMEMMAP 147577ef56e4SKirill A. Shutemov depends on X86_64 147677ef56e4SKirill A. Shutemov ---help--- 147777ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 147877ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 147977ef56e4SKirill A. Shutemov physical address space. 148077ef56e4SKirill A. Shutemov 148177ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 148277ef56e4SKirill A. Shutemov 14836657fca0SKirill A. Shutemov A kernel with the option enabled can be booted on machines that 14846657fca0SKirill A. Shutemov support 4- or 5-level paging. 148577ef56e4SKirill A. Shutemov 148677ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 148777ef56e4SKirill A. Shutemov information. 148877ef56e4SKirill A. Shutemov 148977ef56e4SKirill A. Shutemov Say N if unsure. 149077ef56e4SKirill A. Shutemov 149110971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1492e5008abeSLuis R. Rodriguez def_bool y 14934675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 14948f9ca475SIngo Molnar ---help--- 149510971ab2SIngo Molnar Certain kernel features effectively disable kernel 149610971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 149710971ab2SIngo Molnar supports them), so don't confuse the user by printing 149810971ab2SIngo Molnar that we have them enabled. 14999e899816SNick Piggin 15005c280cf6SThomas Gleixnerconfig X86_CPA_STATISTICS 15015c280cf6SThomas Gleixner bool "Enable statistic for Change Page Attribute" 15025c280cf6SThomas Gleixner depends on DEBUG_FS 15035c280cf6SThomas Gleixner ---help--- 15045c280cf6SThomas Gleixner Expose statistics about the Change Page Attribute mechanims, which 15055c280cf6SThomas Gleixner helps to determine the effectivness of preserving large and huge 15065c280cf6SThomas Gleixner page mappings when mapping protections are changed. 15075c280cf6SThomas Gleixner 15087744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 15097744ccdbSTom Lendacky def_bool y 15107744ccdbSTom Lendacky 15117744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 15127744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 15137744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 151494d49eb3SKirill A. Shutemov select DYNAMIC_PHYSICAL_MASK 15157744ccdbSTom Lendacky ---help--- 15167744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 15177744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 15187744ccdbSTom Lendacky Encryption (SME). 15197744ccdbSTom Lendacky 15207744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 15217744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 15227744ccdbSTom Lendacky default y 15237744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 15247744ccdbSTom Lendacky ---help--- 15257744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 15267744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 15277744ccdbSTom Lendacky 15287744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 15297744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 15307744ccdbSTom Lendacky 15317744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 15327744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 15337744ccdbSTom Lendacky 1534f88a68faSTom Lendackyconfig ARCH_USE_MEMREMAP_PROT 1535f88a68faSTom Lendacky def_bool y 1536f88a68faSTom Lendacky depends on AMD_MEM_ENCRYPT 1537f88a68faSTom Lendacky 1538506f1d07SSam Ravnborg# Common NUMA Features 1539506f1d07SSam Ravnborgconfig NUMA 1540fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1541506f1d07SSam Ravnborg depends on SMP 1542b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1543b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15448f9ca475SIngo Molnar ---help--- 1545506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1546fd51b2d7SKOSAKI Motohiro 1547506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1548506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1549506f1d07SSam Ravnborg NUMA awareness to the kernel. 1550506f1d07SSam Ravnborg 1551c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1552fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1553fd51b2d7SKOSAKI Motohiro 1554b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15557cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1556fd51b2d7SKOSAKI Motohiro 1557fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1558506f1d07SSam Ravnborg 1559eec1d4faSHans Rosenfeldconfig AMD_NUMA 15603c2362e6SHarvey Harrison def_bool y 15613c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15625da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15638f9ca475SIngo Molnar ---help--- 1564eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1565eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1566eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1567eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1568eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1569506f1d07SSam Ravnborg 1570506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15713c2362e6SHarvey Harrison def_bool y 15723c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1573506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1574506f1d07SSam Ravnborg select ACPI_NUMA 15758f9ca475SIngo Molnar ---help--- 1576506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1577506f1d07SSam Ravnborg 15786ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15796ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15806ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15816ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15826ec6e0d9SSuresh Siddha# for details. 15836ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15846ec6e0d9SSuresh Siddha def_bool y 15856ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15866ec6e0d9SSuresh Siddha 1587506f1d07SSam Ravnborgconfig NUMA_EMU 1588506f1d07SSam Ravnborg bool "NUMA emulation" 15891b7e03efSTejun Heo depends on NUMA 15908f9ca475SIngo Molnar ---help--- 1591506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1592506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1593506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1594506f1d07SSam Ravnborg 1595506f1d07SSam Ravnborgconfig NODES_SHIFT 1596d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 159751591e31SDavid Rientjes range 1 10 159851591e31SDavid Rientjes default "10" if MAXSMP 1599506f1d07SSam Ravnborg default "6" if X86_64 1600506f1d07SSam Ravnborg default "3" 1601506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 16028f9ca475SIngo Molnar ---help--- 16031184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1604692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1605506f1d07SSam Ravnborg 1606506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 16073c2362e6SHarvey Harrison def_bool y 1608506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1609506f1d07SSam Ravnborg 1610506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1611506f1d07SSam Ravnborg def_bool y 16123b16651fSTejun Heo depends on X86_32 && !NUMA 1613506f1d07SSam Ravnborg 1614506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1615506f1d07SSam Ravnborg def_bool y 1616b263295dSChristoph Lameter depends on NUMA && X86_32 1617506f1d07SSam Ravnborg 1618506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1619506f1d07SSam Ravnborg def_bool y 1620b263295dSChristoph Lameter depends on NUMA && X86_32 1621b263295dSChristoph Lameter 1622506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1623506f1d07SSam Ravnborg def_bool y 16246ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1625506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1626506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1627506f1d07SSam Ravnborg 16283b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 16293b16651fSTejun Heo def_bool y 16303b16651fSTejun Heo depends on X86_64 16313b16651fSTejun Heo 1632506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1633506f1d07SSam Ravnborg def_bool y 1634b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1635506f1d07SSam Ravnborg 1636506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1637a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16383120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1639a0842b70SToshi Kani help 1640a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1641a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1642a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1643506f1d07SSam Ravnborg 16443b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16453b16651fSTejun Heo def_bool y 16463b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16473b16651fSTejun Heo 1648a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1649a29815a3SAvi Kivity hex 1650a29815a3SAvi Kivity default 0 if X86_32 1651a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1652a29815a3SAvi Kivity 16537a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16547a67832cSDan Williams bool 16557a67832cSDan Williams 1656ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16577a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16589f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16599f53f9faSDan Williams depends on BLK_DEV 16607a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16619f53f9faSDan Williams select LIBNVDIMM 1662ec776ef6SChristoph Hellwig help 1663ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1664ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1665ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1666ec776ef6SChristoph Hellwig they can be used for persistent storage. 1667ec776ef6SChristoph Hellwig 1668ec776ef6SChristoph Hellwig Say Y if unsure. 1669ec776ef6SChristoph Hellwig 1670506f1d07SSam Ravnborgconfig HIGHPTE 1671506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16726fc108a0SJan Beulich depends on HIGHMEM 16738f9ca475SIngo Molnar ---help--- 1674506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1675506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1676506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1677506f1d07SSam Ravnborg entries in high memory. 1678506f1d07SSam Ravnborg 16799f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16809f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16818f9ca475SIngo Molnar ---help--- 16829f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16839f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16849f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16859f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16869f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16879f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16889f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16898c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16909f077871SJeremy Fitzhardinge 16919f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16929f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16939f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16949f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16959f077871SJeremy Fitzhardinge 16969f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16979f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16989f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16999f077871SJeremy Fitzhardinge memory. 17009f077871SJeremy Fitzhardinge 1701c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1702c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1703c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1704c885df50SJeremy Fitzhardinge default y 17058f9ca475SIngo Molnar ---help--- 1706c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1707c885df50SJeremy Fitzhardinge on or off. 1708c885df50SJeremy Fitzhardinge 17099ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1710d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1711d0cd7425SH. Peter Anvin default 64 1712d0cd7425SH. Peter Anvin range 4 640 17138f9ca475SIngo Molnar ---help--- 1714d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1715fc381519SIngo Molnar 1716d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1717d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1718fc381519SIngo Molnar 1719d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1720d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1721d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1722d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1723fc381519SIngo Molnar 1724d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1725d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1726d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1727d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1728d0cd7425SH. Peter Anvin entire low memory range. 1729d0cd7425SH. Peter Anvin 1730d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1731d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1732d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1733d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1734d0cd7425SH. Peter Anvin typical corruption patterns. 1735d0cd7425SH. Peter Anvin 1736d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1737fc381519SIngo Molnar 1738506f1d07SSam Ravnborgconfig MATH_EMULATION 1739506f1d07SSam Ravnborg bool 1740a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1741506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1742506f1d07SSam Ravnborg ---help--- 1743506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1744506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1745506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1746506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1747506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1748506f1d07SSam Ravnborg coprocessor or this emulation. 1749506f1d07SSam Ravnborg 1750506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1751506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1752506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1753506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1754506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1755506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1756506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1757506f1d07SSam Ravnborg intend to use this kernel on different machines. 1758506f1d07SSam Ravnborg 1759506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1760506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1761506f1d07SSam Ravnborg 1762506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1763506f1d07SSam Ravnborg kernel, it won't hurt. 1764506f1d07SSam Ravnborg 1765506f1d07SSam Ravnborgconfig MTRR 17666fc108a0SJan Beulich def_bool y 17676a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1768506f1d07SSam Ravnborg ---help--- 1769506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1770506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1771506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1772506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1773506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1774506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1775506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1776506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1777506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1778506f1d07SSam Ravnborg 1779506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1780506f1d07SSam Ravnborg control registers on other processors can be easily supported 1781506f1d07SSam Ravnborg as well: 1782506f1d07SSam Ravnborg 1783506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1784506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1785506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1786506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1787506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1788506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1789506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1790506f1d07SSam Ravnborg 1791506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1792506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1793506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1794506f1d07SSam Ravnborg 1795506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1796506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1797506f1d07SSam Ravnborg 17987225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1799506f1d07SSam Ravnborg 180095ffa243SYinghai Luconfig MTRR_SANITIZER 18012ffb3501SYinghai Lu def_bool y 180295ffa243SYinghai Lu prompt "MTRR cleanup support" 180395ffa243SYinghai Lu depends on MTRR 18048f9ca475SIngo Molnar ---help--- 1805aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1806aba3728cSThomas Gleixner add writeback entries. 180795ffa243SYinghai Lu 1808aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1809692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1810aba3728cSThomas Gleixner mtrr_chunk_size. 181195ffa243SYinghai Lu 18122ffb3501SYinghai Lu If unsure, say Y. 181395ffa243SYinghai Lu 181495ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1815f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1816f5098d62SYinghai Lu range 0 1 1817f5098d62SYinghai Lu default "0" 181895ffa243SYinghai Lu depends on MTRR_SANITIZER 18198f9ca475SIngo Molnar ---help--- 1820f5098d62SYinghai Lu Enable mtrr cleanup default value 182195ffa243SYinghai Lu 182212031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 182312031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 182412031a62SYinghai Lu range 0 7 182512031a62SYinghai Lu default "1" 182612031a62SYinghai Lu depends on MTRR_SANITIZER 18278f9ca475SIngo Molnar ---help--- 182812031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1829aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 183012031a62SYinghai Lu 18312e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 18326fc108a0SJan Beulich def_bool y 18336a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 18342a8a2719SIngo Molnar depends on MTRR 18358f9ca475SIngo Molnar ---help--- 18362e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1837042b78e4SVenki Pallipadi 18382e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18392e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18402e5d9c85Svenkatesh.pallipadi@intel.com 18412e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1842042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18432e5d9c85Svenkatesh.pallipadi@intel.com 18442e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18452e5d9c85Svenkatesh.pallipadi@intel.com 184646cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 184746cf98cdSVenkatesh Pallipadi def_bool y 184846cf98cdSVenkatesh Pallipadi depends on X86_PAT 184946cf98cdSVenkatesh Pallipadi 1850628c6246SH. Peter Anvinconfig ARCH_RANDOM 1851628c6246SH. Peter Anvin def_bool y 1852628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1853628c6246SH. Peter Anvin ---help--- 1854628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1855628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1856628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1857628c6246SH. Peter Anvin secure hardware random number generator. 1858628c6246SH. Peter Anvin 185951ae4a2dSH. Peter Anvinconfig X86_SMAP 186051ae4a2dSH. Peter Anvin def_bool y 186151ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 186251ae4a2dSH. Peter Anvin ---help--- 186351ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 186451ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 186551ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 186651ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 186751ae4a2dSH. Peter Anvin 186851ae4a2dSH. Peter Anvin If unsure, say Y. 186951ae4a2dSH. Peter Anvin 1870aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1871796ebc81SRicardo Neri def_bool y 1872aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1873aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1874aa35f896SRicardo Neri ---help--- 1875aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1876aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1877796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1878796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1879796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1880796ebc81SRicardo Neri 1881796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1882796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1883796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1884796ebc81SRicardo Neri results are dummy. 1885aa35f896SRicardo Neri 188672e9b5feSDave Hansenconfig X86_INTEL_MPX 188772e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 188872e9b5feSDave Hansen def_bool n 1889df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1890df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1891df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 189272e9b5feSDave Hansen ---help--- 189372e9b5feSDave Hansen MPX provides hardware features that can be used in 189472e9b5feSDave Hansen conjunction with compiler-instrumented code to check 189572e9b5feSDave Hansen memory references. It is designed to detect buffer 189672e9b5feSDave Hansen overflow or underflow bugs. 189772e9b5feSDave Hansen 189872e9b5feSDave Hansen This option enables running applications which are 189972e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 190072e9b5feSDave Hansen itself inside the kernel or to protect the kernel 190172e9b5feSDave Hansen against bad memory references. 190272e9b5feSDave Hansen 190372e9b5feSDave Hansen Enabling this option will make the kernel larger: 190472e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 190572e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 190672e9b5feSDave Hansen will increase the kernel memory overhead of each 190772e9b5feSDave Hansen process and adds some branches to paths used during 190872e9b5feSDave Hansen exec() and munmap(). 190972e9b5feSDave Hansen 191072e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 191172e9b5feSDave Hansen 191272e9b5feSDave Hansen If unsure, say N. 191372e9b5feSDave Hansen 191435e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1915284244a9SDave Hansen prompt "Intel Memory Protection Keys" 191635e97790SDave Hansen def_bool y 1917284244a9SDave Hansen # Note: only available in 64-bit mode 191835e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 191952c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 192052c8e601SIngo Molnar select ARCH_HAS_PKEYS 1921284244a9SDave Hansen ---help--- 1922284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1923284244a9SDave Hansen page-based protections, but without requiring modification of the 1924284244a9SDave Hansen page tables when an application changes protection domains. 1925284244a9SDave Hansen 1926284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1927284244a9SDave Hansen 1928284244a9SDave Hansen If unsure, say y. 192935e97790SDave Hansen 1930506f1d07SSam Ravnborgconfig EFI 19319ba16087SJan Beulich bool "EFI runtime service support" 19325b83683fSHuang, Ying depends on ACPI 1933f6ce5002SSergey Vlasov select UCS2_STRING 1934022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1935506f1d07SSam Ravnborg ---help--- 19368b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1937506f1d07SSam Ravnborg available (such as the EFI variable services). 1938506f1d07SSam Ravnborg 19398b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19408b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19418b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19428b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19438b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19448b2cb7a8SHuang, Ying platforms. 1945506f1d07SSam Ravnborg 1946291f3632SMatt Flemingconfig EFI_STUB 1947291f3632SMatt Fleming bool "EFI stub support" 1948b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19497b2a583aSMatt Fleming select RELOCATABLE 1950291f3632SMatt Fleming ---help--- 1951291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1952291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1953291f3632SMatt Fleming 19544172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19550c759662SMatt Fleming 19567d453eeeSMatt Flemingconfig EFI_MIXED 19577d453eeeSMatt Fleming bool "EFI mixed-mode support" 19587d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19597d453eeeSMatt Fleming ---help--- 19607d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19617d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19627d453eeeSMatt Fleming mode. 19637d453eeeSMatt Fleming 19647d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19657d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19667d453eeeSMatt Fleming the EFI handover protocol must be used. 19677d453eeeSMatt Fleming 19687d453eeeSMatt Fleming If unsure, say N. 19697d453eeeSMatt Fleming 1970506f1d07SSam Ravnborgconfig SECCOMP 19713c2362e6SHarvey Harrison def_bool y 19723c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19738f9ca475SIngo Molnar ---help--- 1974506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1975506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1976506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1977506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1978506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1979506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19809c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1981506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1982506f1d07SSam Ravnborg defined by each seccomp mode. 1983506f1d07SSam Ravnborg 1984506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1985506f1d07SSam Ravnborg 1986506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1987506f1d07SSam Ravnborg 1988506f1d07SSam Ravnborgconfig KEXEC 1989506f1d07SSam Ravnborg bool "kexec system call" 19902965faa5SDave Young select KEXEC_CORE 19918f9ca475SIngo Molnar ---help--- 1992506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1993506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1994506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1995506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1996506f1d07SSam Ravnborg 1997506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1998506f1d07SSam Ravnborg 1999506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 2000506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 2001bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 2002bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 2003bf220695SGeert Uytterhoeven made. 2004506f1d07SSam Ravnborg 200574ca317cSVivek Goyalconfig KEXEC_FILE 200674ca317cSVivek Goyal bool "kexec file based system call" 20072965faa5SDave Young select KEXEC_CORE 200874ca317cSVivek Goyal select BUILD_BIN2C 200974ca317cSVivek Goyal depends on X86_64 201074ca317cSVivek Goyal depends on CRYPTO=y 201174ca317cSVivek Goyal depends on CRYPTO_SHA256=y 201274ca317cSVivek Goyal ---help--- 201374ca317cSVivek Goyal This is new version of kexec system call. This system call is 201474ca317cSVivek Goyal file based and takes file descriptors as system call argument 201574ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 201674ca317cSVivek Goyal accepted by previous system call. 201774ca317cSVivek Goyal 2018b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY 2019b799a09fSAKASHI Takahiro def_bool KEXEC_FILE 2020b799a09fSAKASHI Takahiro 20218e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 20228e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 202374ca317cSVivek Goyal depends on KEXEC_FILE 20248e7d8381SVivek Goyal ---help--- 20258e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 2026d8eb8940SBorislav Petkov the kexec_file_load() syscall. 20278e7d8381SVivek Goyal 2028d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 2029d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 2030d8eb8940SBorislav Petkov loaded in order for this to work. 20318e7d8381SVivek Goyal 20328e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 20338e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 20348e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 20358e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 20368e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 20378e7d8381SVivek Goyal ---help--- 20388e7d8381SVivek Goyal Enable bzImage signature verification support. 20398e7d8381SVivek Goyal 2040506f1d07SSam Ravnborgconfig CRASH_DUMP 204104b69447SPavel Machek bool "kernel crash dumps" 2042506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20438f9ca475SIngo Molnar ---help--- 2044506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2045506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2046506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2047506f1d07SSam Ravnborg a specially reserved region and then later executed after 2048506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2049506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2050506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2051506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2052506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2053506f1d07SSam Ravnborg 20543ab83521SHuang Yingconfig KEXEC_JUMP 20556ea30386SKees Cook bool "kexec jump" 2056fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20578f9ca475SIngo Molnar ---help--- 205889081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 205989081d17SHuang Ying code in physical address mode via KEXEC 20603ab83521SHuang Ying 2061506f1d07SSam Ravnborgconfig PHYSICAL_START 20626a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2063ceefccc9SH. Peter Anvin default "0x1000000" 20648f9ca475SIngo Molnar ---help--- 2065506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2066506f1d07SSam Ravnborg 2067506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2068506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2069506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2070506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2071506f1d07SSam Ravnborg address. 2072506f1d07SSam Ravnborg 2073506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2074506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2075506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2076506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2077506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2078506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2079506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2080506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2081506f1d07SSam Ravnborg 2082ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2083ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2084ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2085ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2086ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2087ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2088ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2089ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2090ceefccc9SH. Peter Anvin for more details about crash dumps. 2091506f1d07SSam Ravnborg 2092506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2093506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2094506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2095506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2096506f1d07SSam Ravnborg is present because there are users out there who continue to use 2097506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2098506f1d07SSam Ravnborg line. 2099506f1d07SSam Ravnborg 2100506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2101506f1d07SSam Ravnborg 2102506f1d07SSam Ravnborgconfig RELOCATABLE 210326717808SH. Peter Anvin bool "Build a relocatable kernel" 210426717808SH. Peter Anvin default y 21058f9ca475SIngo Molnar ---help--- 2106506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2107506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2108506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2109506f1d07SSam Ravnborg but are discarded at runtime. 2110506f1d07SSam Ravnborg 2111506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2112506f1d07SSam Ravnborg must live at a different physical address than the primary 2113506f1d07SSam Ravnborg kernel. 2114506f1d07SSam Ravnborg 2115506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2116506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 21178ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2118506f1d07SSam Ravnborg 21198ab3820fSKees Cookconfig RANDOMIZE_BASE 2120e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 21218ab3820fSKees Cook depends on RELOCATABLE 21226807c846SIngo Molnar default y 21238ab3820fSKees Cook ---help--- 2124e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2125e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2126e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2127e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2128e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2129e8581e3dSBaoquan He code internals. 2130e8581e3dSBaoquan He 2131ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2132ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2133ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2134ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2135ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2136ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2137ed9f007eSKees Cook 2138ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2139ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2140ed9f007eSKees Cook 512MB (8 bits of entropy). 21418ab3820fSKees Cook 2142a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2143e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2144e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2145ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2146ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2147ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2148ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2149ed9f007eSKees Cook theoretically possible, but the implementations are further 2150ed9f007eSKees Cook limited due to memory layouts. 2151e8581e3dSBaoquan He 21526807c846SIngo Molnar If unsure, say Y. 2153da2b6fb9SKees Cook 21548ab3820fSKees Cook# Relocation on x86 needs some additional build support 2155845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2156845adf72SH. Peter Anvin def_bool y 21578ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2158845adf72SH. Peter Anvin 2159506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2160a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21618ab3820fSKees Cook default "0x200000" 2162a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2163a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21648f9ca475SIngo Molnar ---help--- 2165506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2166506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2167506f1d07SSam Ravnborg address which meets above alignment restriction. 2168506f1d07SSam Ravnborg 2169506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2170506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2171506f1d07SSam Ravnborg address aligned to above value and run from there. 2172506f1d07SSam Ravnborg 2173506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2174506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2175506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2176506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2177506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2178506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2179506f1d07SSam Ravnborg above alignment restrictions. 2180506f1d07SSam Ravnborg 2181a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2182a0215061SKees Cook this value must be a multiple of 0x200000. 2183a0215061SKees Cook 2184506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2185506f1d07SSam Ravnborg 2186eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT 2187eedb92abSKirill A. Shutemov bool 2188eedb92abSKirill A. Shutemov ---help--- 2189eedb92abSKirill A. Shutemov This option makes base addresses of vmalloc and vmemmap as well as 2190eedb92abSKirill A. Shutemov __PAGE_OFFSET movable during boot. 2191eedb92abSKirill A. Shutemov 21920483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21930483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21940483e1faSThomas Garnier depends on X86_64 21950483e1faSThomas Garnier depends on RANDOMIZE_BASE 2196eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 21970483e1faSThomas Garnier default RANDOMIZE_BASE 21980483e1faSThomas Garnier ---help--- 21990483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 22000483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 22010483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 22020483e1faSThomas Garnier 22030483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 22040483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 22050483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 22060483e1faSThomas Garnier addresses for each memory section. 22070483e1faSThomas Garnier 22086807c846SIngo Molnar If unsure, say Y. 22090483e1faSThomas Garnier 221090397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 221190397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 221290397a41SThomas Garnier depends on RANDOMIZE_MEMORY 221390397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 221490397a41SThomas Garnier default "0x0" 221590397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 221690397a41SThomas Garnier range 0x0 0x40 221790397a41SThomas Garnier ---help--- 221890397a41SThomas Garnier Define the padding in terabytes added to the existing physical 221990397a41SThomas Garnier memory size during kernel memory randomization. It is useful 222090397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 222190397a41SThomas Garnier address randomization. 222290397a41SThomas Garnier 222390397a41SThomas Garnier If unsure, leave at the default value. 222490397a41SThomas Garnier 2225506f1d07SSam Ravnborgconfig HOTPLUG_CPU 22267c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 222740b31360SStephen Rothwell depends on SMP 2228506f1d07SSam Ravnborg ---help--- 22297c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 22307c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 22317c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 22327c13e6a3SDimitri Sivanich automatically on SMP systems. ) 22337c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 2234506f1d07SSam Ravnborg 223580aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 223680aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 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 243844556530SZhimin Gu depends on 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" 2758fa112cf1SBorislav Petkov depends on OLPC && MFD_CS5535=y && PM_SLEEP 2759bf1ebf00SDaniel Drake ---help--- 276097c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2761bf1ebf00SDaniel Drake 2762cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2763cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2764cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2765cfee9597SDaniel Drake ---help--- 2766cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2767cfee9597SDaniel Drake programmable wakeup source. 2768cfee9597SDaniel Drake 27697feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27707feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 277192e830f2SArnd Bergmann depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2772ed8e47feSRandy Dunlap depends on INPUT=y 2773d8d01a63SDaniel Drake select POWER_SUPPLY 27747feda8e9SDaniel Drake ---help--- 27757feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27767bc74b3dSDaniel Drake - EC-driven system wakeups 27777feda8e9SDaniel Drake - Power button 27787bc74b3dSDaniel Drake - Ebook switch 27792cf2baeaSDaniel Drake - Lid switch 2780e1040ac6SDaniel Drake - AC adapter status updates 2781e1040ac6SDaniel Drake - Battery status updates 27827feda8e9SDaniel Drake 2783a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2784a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2785d8d01a63SDaniel Drake depends on OLPC && ACPI 2786d8d01a63SDaniel Drake select POWER_SUPPLY 2787a0f30f59SDaniel Drake ---help--- 2788a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2789a0f30f59SDaniel Drake - EC-driven system wakeups 2790a0f30f59SDaniel Drake - AC adapter status updates 2791a0f30f59SDaniel Drake - Battery status updates 2792e279b6c1SSam Ravnborg 2793d4f3e350SEd Wildgooseconfig ALIX 2794d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2795d4f3e350SEd Wildgoose select GPIOLIB 2796d4f3e350SEd Wildgoose ---help--- 2797d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2798d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2799d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2800d4f3e350SEd Wildgoose get added here. 2801d4f3e350SEd Wildgoose 2802d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2803d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2804d4f3e350SEd Wildgoose 2805d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2806d4f3e350SEd Wildgoose 2807da4e3302SPhilip Prindevilleconfig NET5501 2808da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2809da4e3302SPhilip Prindeville select GPIOLIB 2810da4e3302SPhilip Prindeville ---help--- 2811da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2812da4e3302SPhilip Prindeville 28133197059aSPhilip A. Prindevilleconfig GEOS 28143197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 28153197059aSPhilip A. Prindeville select GPIOLIB 28163197059aSPhilip A. Prindeville depends on DMI 28173197059aSPhilip A. Prindeville ---help--- 28183197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 28193197059aSPhilip A. Prindeville 28207d029125SVivien Didelotconfig TS5500 28217d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 28227d029125SVivien Didelot depends on MELAN 28237d029125SVivien Didelot select CHECK_SIGNATURE 28247d029125SVivien Didelot select NEW_LEDS 28257d029125SVivien Didelot select LEDS_CLASS 28267d029125SVivien Didelot ---help--- 28277d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 28287d029125SVivien Didelot 2829e279b6c1SSam Ravnborgendif # X86_32 2830e279b6c1SSam Ravnborg 283123ac4ae8SAndreas Herrmannconfig AMD_NB 2832e279b6c1SSam Ravnborg def_bool y 28330e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2834e279b6c1SSam Ravnborg 2835e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2836e279b6c1SSam Ravnborg 2837388b78adSAlexandre Bounineconfig RAPIDIO 2838fdf90abcSAlexandre Bounine tristate "RapidIO support" 2839388b78adSAlexandre Bounine depends on PCI 2840388b78adSAlexandre Bounine help 2841fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2842388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2843388b78adSAlexandre Bounine 2844388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2845388b78adSAlexandre Bounine 2846e3263ab3SDavid Herrmannconfig X86_SYSFB 2847e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2848e3263ab3SDavid Herrmann help 2849e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2850e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2851e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2852e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2853e3263ab3SDavid Herrmann to x86. 2854e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2855e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2856e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2857e3a5dc08SNikolas Nyby modes, it is advertised as fallback platform framebuffer so legacy 2858e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2859e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2860e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2861e3263ab3SDavid Herrmann 2862e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2863e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2864e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2865e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2866e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2867e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2868e3263ab3SDavid Herrmann incompatible with simplefb. 2869e3263ab3SDavid Herrmann 2870e3263ab3SDavid Herrmann If unsure, say Y. 2871e3263ab3SDavid Herrmann 2872e279b6c1SSam Ravnborgendmenu 2873e279b6c1SSam Ravnborg 2874e279b6c1SSam Ravnborg 28751572497cSChristoph Hellwigmenu "Binary Emulations" 2876e279b6c1SSam Ravnborg 2877e279b6c1SSam Ravnborgconfig IA32_EMULATION 2878e279b6c1SSam Ravnborg bool "IA32 Emulation" 2879e279b6c1SSam Ravnborg depends on X86_64 288039f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2881d1603990SRandy Dunlap select BINFMT_ELF 2882a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 288339f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28848f9ca475SIngo Molnar ---help--- 28855fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28865fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28875fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2888e279b6c1SSam Ravnborg 2889e279b6c1SSam Ravnborgconfig IA32_AOUT 2890e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28916b213e1bSDavid Woodhouse depends on IA32_EMULATION 28928f9ca475SIngo Molnar ---help--- 2893e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2894e279b6c1SSam Ravnborg 28950bf62763SH. Peter Anvinconfig X86_X32 28966ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28979b54050bSBrian Gerst depends on X86_64 28985fd92e65SH. J. Lu ---help--- 28995fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 29005fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 29015fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 29025fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 29035fd92e65SH. J. Lu 29045fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 29055fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 29065fd92e65SH. J. Lu option set. 29075fd92e65SH. J. Lu 2908953fee1dSIngo Molnarconfig COMPAT_32 2909953fee1dSIngo Molnar def_bool y 2910953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2911953fee1dSIngo Molnar select HAVE_UID16 2912953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2913953fee1dSIngo Molnar 2914e279b6c1SSam Ravnborgconfig COMPAT 29153c2362e6SHarvey Harrison def_bool y 29160bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2917e279b6c1SSam Ravnborg 29183120e25eSJan Beulichif COMPAT 2919e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 29203120e25eSJan Beulich def_bool y 2921e279b6c1SSam Ravnborg 2922e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 29233c2362e6SHarvey Harrison def_bool y 29243120e25eSJan Beulich depends on SYSVIPC 29253120e25eSJan Beulichendif 2926ee009e4aSDavid Howells 2927e279b6c1SSam Ravnborgendmenu 2928e279b6c1SSam Ravnborg 2929e279b6c1SSam Ravnborg 2930e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2931e5beae16SKeith Packard def_bool y 2932e5beae16SKeith Packard depends on X86_32 2933e5beae16SKeith Packard 29344692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 29354692d77fSAlessandro Rubini bool 293683125a3aSAlessandro Rubini depends on X86_64 || STA2X11 29374692d77fSAlessandro Rubini 2938f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2939f7219a53SAlessandro Rubini bool 294083125a3aSAlessandro Rubini depends on STA2X11 2941f7219a53SAlessandro Rubini 2942e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2943e585513bSKirill A. Shutemov def_bool y 2944e585513bSKirill A. Shutemov 2945e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2946e279b6c1SSam Ravnborg 2947edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2948